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2024-02-24 | Objectives This study aims to assess hydrogen peroxide (HP) penetration within the pulp chamber, color change (CC), physical–chemical properties, and temperature using in-office different concentration bleaching gels with or without violet light. Materials and methods Fifty teeth were divided into five groups ( n = 10) based on the HP concentration bleaching gels used (6% and 35%) and the used violet light (with or without). HP penetration within the pulp chamber was measured using UV–Vis. The CC was evaluated with a digital spectrophotometer. Initial and final concentration, and pH were measured through titration, and a Digital pHmeter, respectively. Temperature analyses were measured through a thermocouple. Statistical analysis included two-way ANOVA, Tukey's, and Dunnett's test (α = 0.05). Results The presence of violet light did not affect the amount of HP within the pulp chamber, or the CC ( p > 0.05). Greater penetration of HP was observed within the pulp chamber, as well as CC when using 35% HP ( p < 0.05). The final concentration of both gels was lower than the initial concentration, regardless of the use of violet light ( p < 0.05). The initial and final pH levels remained neutral and stable ( p > 0.05). The pulp temperature increased when the gels were used in conjunction with violet light ( p < 0.05). Conclusions Using violet light in conjunction with 6% or 35% HP does not alter the physical properties of the bleaching agents, the penetration of HP or enhance color change. However, an increase in temperature was observed when violet light was applied associated with bleaching gels. Clinical relevance While the simultaneous use of violet light with hydrogen peroxide 6% or 35% does not alter the material's properties, it also does not bring benefits in reducing hydrogen peroxide penetration and improving color change. Furthermore, the use of violet light increases pulp temperature. | Low and high hydrogen peroxide concentrations of in-office dental bleaching associated with violet light: an in vitro study | 10.1007/s00784-024-05549-x |
2024-02-23 | The Qinghai-Tibet Plateau (QTP) is characterized by an extreme hypoxia, which may lead to lack of sufficient oxygen for compost production, and thus seriously affecting the compost quality. The moisture content (MC) has a direct effect on the oxygen content of composting pile. At present, the research on the optimum moisture content of compost production on the QTP is still lacking. This study aimed to investigate the influences of MC on fermentation quality of sheep manure composting on the QTP and to further analyze the changes of microbial metabolic function and enzyme activity under different MC. Composting experiment with low MC (45%) and conventional MC (60%) was conducted in both summer and autumn. The results showed that the composting efficiency of 45% MC was better than 60% in both seasons, which was mainly manifested as longer high-temperature period (summer:16 d vs 14 d, autumn: 7 d vs 2 d), higher germination index (summer:136.1% vs 128.6%, autumn:103.5% vs 81.2%), and more humus synthesis (summer:159.8 g/kg vs 151.2 g/kg, autumn:136.1 k/kg vs 115.5 k/kg). The 45% MC can improve microbial metabolism, including increasing the abundance of functional genes involved in carbohydrate metabolism, amino acid metabolism, and nucleotide metabolism and improving the activities of cellulase, β-glucosidase, protease, polyphenol oxidase, and peroxidase. In conclusion, 45% MC can improve the fermentation efficiency and products quality of sheep manure compost on QTP. | The maturity, humus content, and microbial metabolic function of sheep manure compost on the Qinghai-Tibet Plateau can be significantly improved by reducing the moisture content | 10.1007/s11356-024-32437-4 |
2024-02-23 | Considering that the current low-stress cropping method for large-diameter metal bar has the disadvantages of large cutting force and drastic change of loading force, a new low-stress cropping method is proposed based on the co-induced crack initiation by rotating-bending and slotting. Based on the strength theory and fatigue damage theory, the dynamic bending cutting model is established, proving that the prestressed bending action reduces the slotted cutting and cracking forces. The formula of main cutting force during slotting considering rotation speed under the prestressed action is obtained by establishing simulation model combined with the experimental platform of the prestressed rotating-bending cutting and cracking process. Three types of initiation crack are proposed, and the reasonable process parameters for effective connection of slotting and ideal crack initiation type are obtained. The experimental results of 45 steel bar show that the cutting force is reduced to only 75.79% of the traditional cutting slotting, and the crack initiation force is reduced to only 1.88% of the traditional shearing force. Similarly, the test results of Q235 steel, 6061 aluminum alloy, and 304 austenitic stainless steel also show that the cutting force of prestressed slotting is reduced and the slotting and cracking connection can be realized, which can meet the requirements of low-stress slotting and cracking of the bar with large diameter. Graphical abstract Investigation of co-induced crack initiation process by prestressed slotting and rotating-bending in low-stress cropping | Investigation of co-induced crack initiation process by prestressed slotting and rotating-bending in low-stress cropping | 10.1007/s00170-024-13286-4 |
2024-02-23 | The mechanisms of medium- and low-temperature denitrations using selective catalytic reduction (SCR) by combined CO + NH 3 on Mn–Ce/activated carbon (AC) catalysts and their poisoning by SO 2 were investigated. Several Mn–Ce/AC catalysts prepared and then poisoned by SO 2 were used in the study. The physicochemical properties of the catalysts were systematically characterized before and after poisoning, and the mechanism of SO 2 poisoning was proposed. SO 2 poisoning considerably affects the Mn–Ce/AC catalyst, decreasing its denitration rate from 98% to 47.9% and N 2 selectivity from 96 to 85%. This can be attributed to several phenomena. SO 2 poisoning increases the surface roughness of the catalyst and results in the formation of Mn(SO 4 ) 2 , other sulfates, and other substances, which block the catalyst pores and reduce the content of the C and O elements on the catalyst surface as well as its specific surface area, consequently decreasing the adsorption area available for the reaction gas. Moreover, the crystallinity of MnO x on the surface of the catalyst increases, decreasing the contents of Mn 4+ , Ce 4+ and chemosorbed oxygen. In addition, the surface functional groups, such as –COOH, –OH, and C=O, are destroyed, reducing the adsorption sites of the reaction gas and the adsorption capacity of the catalyst, consequently inhibiting the SCR reaction. Ce can reduce the effects of SO 2 poisoning on the catalyst because Ce 4+ can improve its oxygen storage capacity, increase the adsorption sites for the reaction gas, and react with SO 2 , preventing sulfate formation and pore blockage. However, excessive Ce loading causes metal agglomeration on the catalyst surface, reducing its denitration efficiency. Graphical Abstract After SO 2 poisoning, the contents of Mn4+, Mn3+, and Ce4+ decreased in the Mn -Ce/AC catalysts, inhibiting the synergistic reaction between Mn and Ce, which decreased the number of oxygen vacancies and Oβ, consequently inhibit the reaction's conversion to fast selective catalytic reduction. Thus, SO 2 destroyed the functional groups; occupied the oxygen vacancies and active site; and destroyed the –COOH, O–H, and C=O functional groups on the surface of the Mn–Ce/AC catalyst, reducing the acidity and number of active sites on the catalyst surface. | Mechanisms of Medium- and Low-Temperature Denitration by Combined CO + NH3 on Mn–Ce/AC Catalysts and Their SO2 Poisoning | 10.1007/s10562-024-04601-5 |
2024-02-23 | The oxidation and spontaneous combustion of water immersion coal threatens the mine safety production after experiencing water evacuation in the underground goaf. The weathering effect creates disparate water content in coal that results in the distinct oxidation process. This paper investigates the immersion coal pore evolution and oxygen adsorption behavior at different water contents from the molecular dynamics perspective. Proximate analysis, ultimate analysis, 13 C NMR spectrum research, and XPS spectrum were used to construct the macromolecular coal model. There is a double-peak behavior for the water immersion coal porosity and specific surface area. The maximum porosity of water immersion coal was 25.7% and 28.9% arising at 5.9% and 10.2% water content, respectively. The adsorption loading and average oxygen adsorption density both exhibited the rise-decline-rise-decline trend with two remarkable peaks presented at the same site. The two peaks possessed the lowest oxygen adsorption total energy level of − 23.37 and − 21.73 kcal/mol. Temperature rise trial was conducted to evaluate and verify the double-peak characterization of the water immersion coal at the low-temperature oxidation stage. The temperature rising rate versus the heating time of higher water content slowed down at an elevated water bath temperature. There were two maximum immersion coal temperatures, 85.52 and 85.66 °C, with optimum water content of 6.0% and 12.0%, respectively, at the stabilization stage. The obtained achievement of the crucial optimum water content has important theoretical guiding significance for the scientific prevention of the water immersion coal oxidation spontaneous combustion disaster in an underground goaf. | Oxidation Characterization of Water Immersion Coal on Pore Evolution and Oxygen Adsorption Behavior | 10.1007/s11053-024-10314-8 |
2024-02-23 | Jurassic sedimentary sequences suitable for nuclear waste storage in northern Germany consist of organic-lean claystone and were uplifted to < 100 m depth in the Hils Syncline area (southern Lower Saxony Basin). This Hils Syncline, showcasing a northwestward increase in thermal maturity, facilitates the study of shale petrophysical properties influenced by burial history. This study introduces a 3D-thermally calibrated numerical model of the Hils Syncline area to analyze its geodynamic evolution and maturity variations. It provides new vitrinite reflectance and sonic velocity data for modeling calibration and erosion estimation. The Hils Syncline area has undergone continuous subsidence, interrupted by a Cretaceous uplift documented by an erosional unconformity. During the latest Early Cretaceous, Jurassic rocks underwent maximum burial reaching up to several thousand meters depth and temperatures up to 160 °C in the northwest. The Late Cretaceous inversion caused stronger erosion towards the northwest removing up to 3300 m of sediment compared to about 1300 m in the south, according to vitrinite reflectance-based estimations. Numerical modeling results along the study area indicate decreasing porosity and permeability northwestward with increasing thermal maturity. Porosity and vertical permeability decreased to 5–14% and 2.8 × 10 –23 to 1.5 × 10 –19 m 2 [1 mD = 10 −15 m 2 ], respectively, while vertical thermal conductivity increased to 1.30–2.12 (W/m/K). These trends of porosity/permeability and thermal conductivity with burial align with sonic velocity and published experimental porosity data, except for the thermally most mature region (Haddessen). This anomaly is tentatively attributed here to localized overpressure generation in the Posidonia Shale during maximum burial, affecting both the underlying Pliensbachian and overlying Doggerian units. Graphical abstract 3D numerical model of the Hils Syncline and surrounding area revealing that a northwestward increase in maximum burial resulted in higher temperatures and varying maturity levels. While most locations align well with calibration data (i.e. measured vitrinite reflectance and porosity), discrepancies arise in the Haddessen/Bensen area. The mismatch between porosity, vitrinite reflectance, and sonic velocity response indicates local overpressure in the northernmost region mainly during the Cretaceous. It was likely caused by gas generation in the Posidonia Shale affecting nearby Lower and Middle Jurassic units. | 3D basin modeling of the Hils Syncline, Germany: reconstruction of burial and thermal history and implications for petrophysical properties of potential Mesozoic shale host rocks for nuclear waste storage | 10.1007/s00531-024-02384-z |
2024-02-23 | Research on wind speed characteristics is of interest for many disciplines from renewable energy to ecology. Whereas mean values and trends are commonly studied, less attentions is paid to the evaluation of other features such as low-wind conditions. However, there is no clear definition of “low-wind” on the literature. Here we propose the Beaufort scale to characterize low-wind values over Europe through a fixed threshold of 3.3 m/s (“light breeze" category). Climatological (1979–2018) assessment is performed using ERA5 reanalysis hourly data. The limited amount of observational stations indicate a 40-year averaged amount of around 3500 low-wind hours/year, comparable to the corresponding ERA5 reanalysis cells, which shows severe limitations over mountainous areas. The European domain features a strong north–south low-wind hours gradient. Remarkable patterns are obtained over coasts and complex orography regions. Seasonal low-wind variability range around 20–25% for most of the regions, and interannual coefficient of variability from 0.05 to 0.17. Oceanic regions present smaller low-wind values than land areas, with Atlantic and Mediterranean regions behaving differently. The largest annual spells (consecutive) hourly low-wind episodes are within the range from 5 to 10 days, (from 120 to 240 h) over many land areas. Annual mean hourly wind spells typically extend from 15 to 25 h, with more than 200 episodes. | Low-wind climatology (1979–2018) over Europe from ERA5 reanalysis | 10.1007/s00382-024-07123-3 |
2024-02-23 | With the proposal of dual-carbon targets, the low-carbon transition of resource-based cities (RBCs) has become an urgent task. Industrial transition is an essential method of ensuring energy supplies and achieving the “double carbon” goal. However, an in-depth discussion on the theoretical issues associated with the intrinsic drivers and pathways of influence between industrial structure and carbon emissions is lacking. This study investigates the mechanism underlying industrial transitions and associated effects on carbon emission intensity (CAIN) and provides guidance for designing low-carbon transition pathways for RBCs. To achieve this goal, a theoretical framework is constructed to examine the direct and indirect effects of industrial structure on CAIN and an empirical analysis is performed on the impact of industrial structure upgrades on CAIN using panel data from 107 RBCs in China from 2002 to 2017. The results show that: (1) Industrial diversification has more significant impacts than industrial specialization on reducing CAIN. However, the inhibitory effect of industrial diversification on CAIN is weaker in nonresource-depleted cities than in resource-depleted cities; (2) technological innovation and external investment have a significant mediating effect on the relationship between industrial structure and carbon emissions. Moreover, the impact of technological innovation on reducing CAIN through industrial structure transition is much greater than that of external investment; (3) RBCs with low industrial transition potential should focus on investments and innovation capacity, while high-potential RBCs should optimize industrial structure. Tailored policies considering local requirements and development stages are essential for achieving the “double carbon” goal in RBCs. | How does industrial transition drive low-carbon transition? Evidence from China’s resource-based cities | 10.1007/s10668-024-04575-9 |
2024-02-23 | A radio frequency ion source has been developed for a low-energy charged particle accelerator system. Characterization of the ion source has been carried out and optimization of the operating parameters such as RF power at 26.68 MHz, extraction voltage, magnetic field, gas pressure, and focusing electrode has been performed. A maximum ion current of 1.4 mA has been achieved at the best operating parameters. | Development and characterization of radio frequency ion source | 10.1007/s12648-024-03110-w |
2024-02-23 | Lorentz symmetry appears as a quite robust feature of the strongly interacting Dirac materials even though the lattice interactions break such a symmetry. We here demonstrate that the Lorentz symmetry is restored at the quantum-critical point (QCP) separating the tilted Dirac semimetal, breaking this symmetry already at the noninteracting level, from a gapped s -wave superconducting instability. To this end, we employ a one-loop ϵ = (3 − D )-expansion close to the D = 3 upper critical dimension of the corresponding Gross-Neveu-Yukawa field theory. In particular, we show that the tilt parameter is irrelevant and ultimately vanishes at the QCP separating the two phases. In fact, as we argue here, such a Lorentz symmetry restoration may be generic for the strongly interacting tilted Dirac semimetals, irrespective of whether they feature mirror-symmetric or mirror-asymmetric tilting, and is also insensitive to whether the instability represents an insulator or a gapped superconductor. The proposed scenario can be tested in the quantum Monte Carlo simulations of the interacting tilted Dirac fermion lattice models. | Tilted Dirac superconductor at quantum criticality: restoration of Lorentz symmetry | 10.1007/JHEP02(2024)181 |
2024-02-23 | To solve the problem of a narrow flow range of a vane diffuser at high speed while maintaining adequate centrifugal compressor performance, the wing diffuser of a turbocharged transonic compressor is taken as the object; the numerical simulation method is adopted, the effects of low-solidity treatment, combined treatment of low solidity and slotting, combined treatment of low solidity, and casing on compressor stability and aerodynamic performance are studied, respectively. The results of low-solidity treatment show that a low-solidity diffuser can broaden the flow range, even 1.8 times that of the vaneless diffuser. The performance decrease is smaller than the vaneless diffuser (the maximum reduction of pressure ratio is 6.4% less, and the maximum reduction of efficiency is 4.1% less), but the stall boundary is shifted to the right. Then, the low-solidity diffuser is slotted in different axial and radial locations. They are slotting treatment of vane root, slotting treatment of vane tip, and casing treatment of circumferential slot at wheel cover. The results show that the location of the slot is the critical parameter; the location of the shockwave core area can determine it. Slotting treatment of the vane root, casing treatment of the circumferential slot, and slotting treatment of the vane tip can enhance stability from strong to weak and performance loss from large to small. Among them, slotting treatment at the front half-chord root of the low-solidity diffuser vane can maximise the stable working flow range while the problem of stall boundary shifts to the right can be solved. The stall margin is widened to 1.8 times, the flow range is enlarged to 1.7 times, and the flow range is even 2.3 times that of the vaneless diffuser. Although it also causes the greatest loss of aerodynamic performance, the performance is still better than the vaneless diffuser. | Mechanism of stability enhancement of vane diffuser with different combined treatment methods | 10.1007/s40430-024-04683-7 |
2024-02-22 | The impetus of this paper is to examine the natural convection of low-Prandtl-number fluid flow driven by buoyancy force in a differentially heated enclosure using the single-relaxation-time thermal lattice Boltzmann method owing to the broad range of applications of convective-based problems in industry, such as melting processes as well as energy storage systems. In this study, a proper force term incorporated in the collision operator has been utilized for computer code convergence (especially for Prandtl numbers less than 0.71). The side walls of the geometry are maintained by constant temperatures, T h and T c , and the upper and lower walls are thermally insulated. The effects of Prandtl ( $$0.05\le {\text{Pr}}\le 0.71$$ 0.05 ≤ Pr ≤ 0.71 ) and Rayleigh numbers ( $${10}^{4}\le {\text{Ra}}\le {5\times 10}^{5}$$ 10 4 ≤ Ra ≤ 5 × 10 5 ) on the temperature fields, streamline functions, and average Nusselt number have been studied and found that at a given Prandtl number, the magnitude of vortices at the corner of the enclosure rises while those could disappear by Prandtl number increase. In addition, in the vicinity of hot and cold walls, the isotherms concentration increases due to rising temperature gradient and Prandtl number. The heat transfer coefficient grows with an increase in Ra and Pr numbers, experiencing a dramatic rise of 66.67% at the hot wall for Pr = 0.1. Similarly, the maximum velocity values near the cold wall rose by 185.71%. The suggested scheme has been validated by results shown in the literature, and excellent agreement has been found. | Transport Phenomena Study of Low-Prandtl-Number Fluid Flow Using Thermal Lattice Boltzmann Technique | 10.1007/s13369-024-08786-0 |
2024-02-22 | The main physicochemical characteristics of novel artisanal chocolates (both dark and milky) intended for vegan consumers or for those requiring assumption of fewer simple sugars, were analysed. Replacement of milk (with coconut copra, almonds, and soy protein isolates), and sucrose (with coconut sugars, stevia and erythritol, respectively) in dark chocolate, were accounted for by means of texture analysis, rheology, water activity, fatty acid composition, differential scanning calorimetry (DSC) and fast field cycling (FFC) nuclear magnetic resonance (NMR) relaxometry. The vegan sample (i.e., the milk-less one) showed lower values of hardness and adhesiveness as well as a larger peak in the melting behavior at the calorimetric evaluation (DSC). Moreover, the absence of milk resulted in the halving of the yield stress and a decrease in both the apparent and Casson’s viscosity. In the sample of chocolate with less sucrose, the peak temperatures measured at the DSC indicate crystallization of cocoa butter in its best form (Vβ 2 ), unlike in dark chocolate, due to the different sugar composition. Similarly, the Casson yield stress (τ 0 ), increased significantly (almost 70%), with the substitution of sugar. Finally, the results of NMR FFC relaxometry made it possible to identify aggregates of different sizes, laying the basis for its use as a rapid, non-destructive method for chocolate analysis. | Vegan and sugar-substituted chocolates: assessing physicochemical characteristics by NMR relaxometry, rheology, and DSC | 10.1007/s00217-023-04457-w |
2024-02-22 | Due to the rapid growth in small-scale energy systems, the scientific community has rekindled its interest in developing a more efficient Tesla turbine owing to its simple design, low cost and efficient operation at these scales. This article is a combined effort of numerical and experimental investigation to improve a Tesla turbine’s overall performance using several inlet and outlet configurations. After achieving good accuracy ( $$\approx $$ ≈ 6% difference between the results) with the experimental result, we continue the numerical investigation for three different circular-to-slit type nozzle configurations at a total pressure and temperature difference of 2 bar and 50 $$^\circ $$ ∘ C, respectively. Results from the numerical simulation indicate that nozzle 3 delivers the highest peak Mach no and uniformity across the slits. The maximum disparity in peak Mach no across the slits reduced from 12 to 25%. Furthermore, we experimentally investigate the turbine in bi and uni-axial outlet configurations with compressed air at 6 bar for nozzle 1. We observe a maximum RPM of $$\approx $$ ≈ 11,000 for bi-axial outlet configuration, whereas the RPM crossed for $$\approx $$ ≈ 13,300 for uni-axial outlet configuration. These observations suggest that we can improve the maximum turbine power output by $$\approx $$ ≈ 38% for uni-axial outlet configuration. Finally, we measure the electrical power generated by the turbine in a bi-directional outlet configuration by coupling the turbine with a generator. In combination, these observations would help optimize both inlet and outlet configurations suitable for the later versions of the Tesla turbine. | Experimental and numerical investigation of the effect of inlet and outlet configurations on the performance enhancement of a 100 Watts-class Tesla turbine | 10.1007/s12046-023-02393-9 |
2024-02-22 | The aim of the study was to investigate the impact of multiwave locked system (MLS M1) emitting synchronized laser radiation at 2 wavelength simultaneous ( λ = 808 nm, λ = 905 nm) on the mesenchymal stem cells (MSCs). Human MSCs were exposed to MLS M1 system laser radiation with the power density 195–318 mW/cm 2 and doses of energy 3–20 J, in continuous wave emission (CW) or pulsed emission (PE). After irradiation exposure in doses of energy 3 J, 10 J (CW, ƒ = 1000 Hz), and 20 J (ƒ = 2000 Hz), increased proliferation of MSCs was observed. Significant reduction of Fluo-4 Direct™ Ca 2+ indicator fluorescence over controls after CW and PE with 3 J, 10 J, and 20 J was noticed. A decrease in fluorescence intensity after the application of radiation with a frequency of 2000 Hz in doses of 3 J, 10 J, and 20 J was observed. In contrary, an increase in DCF fluorescence intensity after irradiation with laser radiation of 3 J, 10 J, and 20 J (CW, ƒ = 1000 Hz and ƒ = 2000 Hz) was also shown. Laser irradiation at a dose of 20 J, emitted at 1000 Hz and 2000 Hz, and 3 J emitted at a frequency of 2000 Hz caused a statistically significant loss of MSC viability. The applied photobiomodulation therapy induced a strong pro-apoptotic effect dependent on the laser irradiation exposure time, while the application of a sufficiently high-energy dose and frequency with a sufficiently long exposure time significantly increased intracellular calcium ion concentration and free radical production by MSCs. | Effect of photobiomodulation therapy on the morphology, intracellular calcium concentration, free radical generation, apoptosis and necrosis of human mesenchymal stem cells—an in vitro study | 10.1007/s10103-024-04008-z |
2024-02-21 | A hot rolled low carbon (0.17%) steel strip with 1.72% Mn, 1.35% Si and micro-alloyed with 0.04% Ti, 0.02% Nb was subjected to single stage quench partitioning followed by air cooling resulted in ultra high strength levels between 1039 and 1178 MPa with a total elongation between 21.6 and 29.9% with the product of strength and elongation exceeding 30 GPa at selected conditions. The yield ratio varied between 0.39 and 0.51. To achieve this range of properties, the steel was subjected to austenitization at 925 °C for 2 min followed by quenching in salt bath. The partitioning was carried out between 291 and 391 °C for 5 min in the salt bath followed by air cooling. The steel microstructure showed ferrite-bainite as the major phase with small amount of martensite and retained austenite. | Development of ultra high strength steel with high ductility by air cooling post single stage quench partitioning | 10.1007/s12666-024-03276-1 |
2024-02-21 | Background Photosynthesis is a fundamental process that underlies the formation of crop yield, wherein light serves as the driving force and carbon dioxide (CO 2 ) as the raw material. These two factors have a direct influence on the progress and efficiency of photosynthesis in crops. Rapeseed is one of the four major oilseed crops worldwide. Plateau rapeseed has now become a research hotspot. However, the lack of high-yielding rapeseed germplasm resources on the plateau and the highly efficient strategy for screening them severely affect the development of rapeseed industry in plateau. Results In the rapeseed experimental fields located on the plateau (Lhasa, Tibet), we measured abundant sunlight, characterized by an average daily photosynthetically active radiation (PAR) of 1413 μmol m −2 s −1 . In addition, the atmospheric CO 2 concentrations range from 300 to 400 ppm, which is only two-thirds of that in the plain (Chengdu, Sichuan). We found that under different measurement conditions of light intensity and CO 2 concentration, different rapeseed genotypes showed significant differences in leaf photosynthetic efficiency during the seedling stage. Moreover, the rapeseed materials with high photosynthetic efficiency under low CO 2 concentrations rather than high light intensity, exhibited significant advantages in biomass, yield, and oil content when cultivated on the plateau, indicating that the CO 2 is the key environmental factor which limited rapeseed production in plateau. Based on photosynthetic efficiency screening under low CO 2 concentrations, six rapeseed varieties SC3, SC10, SC25, SC27, SC29 and SC37, shown significantly higher yields in plateau environment compared to local control variety were obtained. In addition, the adaptability of rapeseed to plateau was found to be related to the activities of key Calvin cycle enzymes and the accumulation of photosynthetic products. Conclusions This study established a screening strategy for plateau high-yielding rapeseed materials, obtained six varieties which were suitable for plateau cultivation, explored the mechanism of rapeseed response to the plateau environment, and thus provides a feasible strategy for plateau-adapted rapeseed breeding. | Low CO2 concentration, a key environmental factor for developing plateau adapted rapeseed | 10.1186/s13068-024-02481-w |
2024-02-21 | Background In Tanzania, firewood, charcoal, and agricultural waste play a crucial role in daily life as sources of cooking energy, especially in rural areas. Using these energy sources contributes to deforestation and the emission of harmful substances, leading to health problems. This study highlights the potential of faecal sludge briquettes as an innovative, environmentally friendly, and sustainable alternative to traditional energy sources to meet the increasing demand for cooking energy in Tanzania. The process involved sludge characterization, drying, sorting, carbonization, milling, briquette making, and characterization. Results A study was conducted to assess the presence of zinc (Zn), cadmium (Cd), and lead (Pb) in faecal sludge collected from households. The results indicates that the levels of these metals were all within the acceptable limits set by the Tanzanian Standards (TZS) for sludge disposal and use in the environment, which are 5.00 mg/L, 5.00 mg/L, and 30.00 mg/L, respectively. Septic tanks and pit latrines sludge had a concentration of 0.5 mg/L and 0.5 mg/L for Zn, 0.55 mg/L, and 0.6 mg/L for Cd, and 10.01 mg/L and 4.87 mg/L for Pb, respectively. Adding 75% charcoal dust improved the gross and net heating values from 10.47 and 10.16 to 19.29 and 18.86 MJ/kg, respectively. Similarly, adding 50% charcoal dust improved the gross and net heating values to 19.24 and 18.78 MJ/kg. The emission of particulate matter (micrograms/m 3 ) was reduced from 30.4 and 35 to 10.3 and 11.8 for PM 2.5 and 7 and 8 for PM 10, while carbon monoxide emission decreased from 51.2 to 19.7 ppm. Conclusion The results strongly suggest that briquettes made of carbonized faecal sludge mixed with other biomass materials could offer an alternative to traditional solid fuels, with the added benefits of reducing greenhouse gas emissions, deforestation, and longer burning times. | Production of low emission briquettes from carbonized faecal sludge as an alternative source of cooking energy | 10.1186/s13705-024-00449-0 |
2024-02-21 | The identification of new refrigerants characterized by low GWP (< 150), as required at international level by several agreements and regulations, is still far from the conclusion. In particular, for a proper selection, the thermophysical properties of hydro(chloro) fluoroolefins (H(C)FOs) are required, but their knowledge is still scarce for several of these fluids. Amongst these, R1130(E) has recently get some attention as a component, with R1336mzz(Z), of the azeotropic binary mixture (R514A), that could be applied as a substitute for R123 in centrifugal chillers, high-temperature heat pumps, and organic Rankine cycles. R1130(E) is a hydrochloroolefin characterized by a relatively high normal boiling temperature (320.9 K) and belongs to the ASHRAE safety group B1. Its properties are still not widely studied and, in particular, a very limited number of data is available in the peer reviewed literature for the thermal conductivity. Thus, in this paper, a set of experimental thermal conductivity data, performed with a double THW apparatus, will be presented. The data are measured in the range of temperatures between 243.15 and 313.15 K, with pressures up to 8 MPa. | Thermal Conductivity Measurements for the Hydrochloroolefin R1130(E) | 10.1007/s10765-024-03341-3 |
2024-02-21 | High salt intake and compliance to low-sodium (LS) diets are critical in hypertension. Salt reduction in processed foods can help to achieve the target sodium intake. To verify the hypothesis that an innovative LS formulation of a traditional bread could result in a reduction of sodium intake and blood pressure, we performed a 6-month randomized controlled pilot trial on hypertensive patients. We additionally explored the effects of sodium restriction on blood pressure and fecal cultivable bacteria. Fifty-seven patients were randomized in three groups. Group A ( n = 19) followed a free diet using standard bread (750 mg Na/100 g), group B ( n = 18) followed a LS diet (2300 mg Na/die) using standard bread, group C ( n = 20) followed a LS diet (2300 mg Na/die) using LS bread (280 mg Na/100 g). We measured 24-h urinary sodium, blood pressure, routine parameters, fecal microbial counts (26 patients). After 6 months, as compared to group A, group C showed a reduction of 24-h urinary sodium excretion (-908 mg/24 h), diastolic pressure (-9 mmHg) and microbial counts of Bacteroides , Porphyromonas , Prevotella , Enterobacteriaceae, Staphylococcus, Micrococcus. These results suggest that LS bread could increase the adherence to a LS diet, reducing sodium excretion, diastolic pressure and abundance of some fecal cultivable bacteria. Trial registration Registration nr. NCT03127553, on 25/04/2017. | Effects of low-sodium bread on dietary compliance and fecal cultivable bacteria in a randomized controlled pilot trial in hypertensive subjects | 10.1186/s40795-024-00838-w |
2024-02-20 | Dense and flat freestanding Bi 2 Te 3 -based thermoelectric nano films were successfully fabricated by sputtering technology using a newly developed nano graphene oxide membrane as a substrate. On-chip micro temperature controllers were integrated using conventional micro-electromechanical system technology, to achieve energy-efficient temperature control for low-power electronics. The tunable equivalent thermal resistance enables an ultrahigh temperature control capability of 100 K mW −1 and an ultra-fast cooling rate exceeding 2000 K s −1 , as well as excellent reliability of up to 1 million cycles. Multidimensional integration and multifunctional component assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics. However, this inevitably exacerbates the inhomogeneity of temperature distribution in microsystems, making precise temperature control for electronic components extremely challenging. Herein, we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50 × 50 μm 2 , which are fabricated from dense and flat freestanding Bi 2 Te 3 -based thermoelectric nano films deposited on a newly developed nano graphene oxide membrane substrate. Its tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics. A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445 μW, resulting in an ultrahigh temperature control capability over 100 K mW −1 . Moreover, an ultra-fast cooling rate exceeding 2000 K s −1 and excellent reliability of up to 1 million cycles are observed. Our proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics. | On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics | 10.1007/s40820-024-01342-3 |
2024-02-20 | In this present research, cost-effective methods for synthesizing structural materials have been adopted, focusing on low-cost Fe-Mn-Al-Si steel for an electric vehicle. The main procedure involves a two-step thermomechanical method that comprises hot forging (1100 °C) and hot rolling (800, 900, 1000 °C) followed by water quenching. In this design approach, both hard and soft phases of a microstructure were obtained to achieve a balance between strength and ductility properties. This microstructure comprises dislocation-enriched strain-induced twins and martensite along with both microsized and nanosized TiC precipitates. The synthesized material thus exhibits a unique combination of remarkable tensile strength (~2 GPa) together with low density (6.9 ± 0.05 gcm −3 ) and excellent ductility (~50% total elongation). This significant combination of properties is attributed to combined TWIP and TRIP effects along with the precipitation of TiC. | Development of High-Strength Low-Density Steel for Emerging Lightweight Electric Vehicle Technologies | 10.1007/s11665-024-09260-6 |
2024-02-20 | Low temperatures pose a critical challenge to aquaculture operations, as they can significantly affect fish health and overall productivity. The study investigated the impact of low-temperature stress on juvenile golden pompano, focusing on serum indicators, intestinal microbiome, and intestinal transcriptome. With 180 fish divided into low-temperature (18 ± 0.5) ℃ and control (28 ± 0.5) ℃ groups, the gradual temperature decrease mimicked natural seasonal changes. Each group had 3 replicates, with 30 fish per replicate. Results indicated significant effects on serum indicators, including enzyme activity and ion concentrations. While intestinal flora richness was not drastically affected, the dominant flora composition changed. Transcriptome analysis revealed 1752 differentially expressed genes, with enrichment in pathways related to circadian rhythm, proteasome, metabolism, and signaling pathways. This research enhances understanding of cold stress responses in juvenile golden pompano, offering insights for tailored aquaculture management to promote robust and stress-resistant fish stocks. The findings contribute to sustainable aquaculture practices and lay the groundwork for future studies on temperature stress and fish health. | Effects of low-temperature stress on serum biochemical indicators, intestinal microbiome, and transcriptome of juvenile golden pompano (Trachinotus ovatus) | 10.1007/s10499-024-01436-0 |
2024-02-20 | This paper suggests a new onboard calibration procedure for star sensors installed on low Earth orbit satellites. In this procedure, all the error factors are investigated, and an accurate model of the star sensor is presented. Then, a new scenario is proposed for producing real data from a star sensor installed on a satellite while the satellite is moving in orbit. These sensor data are entered into the unscented Kalman filter as measurement data, and the sensor parameters, including focal length and principal point, are estimated. In the following, the estimated parameters are entered into the linear Kalman filter, and the misalignment error is estimated. Finally, the proposed procedure is simulated, and its performance is checked. The simulation results show the high accuracy and convergence speed of the suggested algorithm. | A new procedure for onboard calibration of star sensors installed on low Earth orbit satellite | 10.1186/s44147-024-00385-y |
2024-02-20 | Some plant species have a kind of mixed pollination system—ambophily—which rely both on biotic and abiotic (most commonly wind) as pollen vectors. Ambophily remains poorly addressed in the pollination literature and may have been overlooked because existing studies do not quantify the wind contribution in animal-pollinated species. After observing pollen transport by the wind in an Orobanchaceae species with ornithophilous floral phenotype, we hypothesize that this species could be ambophilous. Esterhazya eitenorum Barringer is a (sub-)shrub endemic to a high-altitude grassland ( campos de altitude ) area in southeastern Brazil. Pollinated mainly by hummingbirds and secondarily by large bees, it presents features generally associated with ornithophily. Bird-pollinated species are not expected to be ambophilous, due to their high resource investment in floral construction and maintenance. However, here we detect ambophily in E. eitenorum by testing the potential for pollen export by the wind as well as seed set after floral visitor exclusion and spontaneous self-pollination treatments, and comparing these with natural conditions. Esterhazya eitenorum has an ambophilous pollination system, with effect size analyses between floral visitor exclusion treatments and natural conditions revealing significant contributions from both abiotic and biotic components. Although its floral phenotype corresponds to the main pollinator, the occurrence of ambophily in E. eitenorum underscores the need for an independent approach to the association of floral phenotypes with pollination vectors, in particular for the detection and better understanding of the evolution of mixed pollination systems. | An unexpected case of wind pollination: ambophily in an ornithophilous tropical mountaintop Orobanchaceae | 10.1007/s00606-024-01890-6 |
2024-02-20 | We provide a formulation of quantum mechanics based on the cohomology of the Batalin-Vilkovisky (BV) algebra. Focusing on quantum-mechanical systems without gauge symmetry we introduce a homotopy retract from the chain complex of the harmonic oscillator to finite-dimensional phase space. This induces a homotopy transfer from the BV algebra to the algebra of functions on phase space. Quantum expectation values for a given operator or functional are computed by the function whose pullback gives a functional in the same cohomology class. This statement is proved in perturbation theory by relating the perturbation lemma to Wick’s theorem. We test this method by computing two-point functions for the harmonic oscillator for position eigenstates and coherent states. Finally, we derive the Unruh effect, illustrating that these methods are applicable to quantum field theory. | Homological quantum mechanics | 10.1007/JHEP02(2024)137 |
2024-02-19 | Thermoelectric generation (TEG)-based waste heat recovery technology is an example of a low-grade energy recovery application. This study proposes a waste heat recovery system that can store the recovered energy and run low-power automotive car lamps. Experimental analysis was conducted to examine the output characteristics of the TEG-based waste heat recovery system, focusing on how the structural components and operational parameters influenced these characteristics. The study also explored and optimized the working strategy of the system for driving light-emitting diode (LED) car lamps. Both the dynamic output characteristics of the system and the lighting attenuation rule of the lamps were evaluated. The results revealed that increasing the heating temperature would improve the recovered energy of the system. However, when a high-power LED chip was used for heat generation instead of an electrically controlled heating plate, a slightly larger amount of energy was collected at the expense of a slightly lower thermoelectric conversion rate. Furthermore, connecting a supercapacitor to the waste heat recovery system for energy storage increased the operational time of the lamps. The supercapacitor also served as a buffer for power and voltage fluctuations caused by variations in the heating temperature. These findings demonstrate that the waste heat recovery system not only meets the requirements of the LED car lamps but can also power other low-voltage and low-power devices. | Harvesting waste heat based on thermoelectric generation to drive LED car lamps | 10.1007/s10973-024-12915-0 |
2024-02-19 | While the position of alpine and arctic treelines can be predicted by climatic data, the underlying biological mechanisms are still unclear. In a recent paper in this journal (Körner C, Lenz A, Hoch G (2023) Chronic in situ tissue cooling does not reduce lignification at the Swiss treeline but enhances the risk of 'blue' frost rings. Alpine Botany https://doi.org/10.1007/s00035-023-00293-6 ) we presented results of an in situ stem-cooling experiment at a Swiss treeline site. The experiment provided answers to two entirely different questions, related to xylogenesis at treeline: (a) the absence of chronic effects of low temperature on lignification, and (b) a high time resolution insight into the rare occurrence of damages in young, still undifferentiated, and thus, non-lignified cells at the occasion of an exceptional early season frost event. In the last issue of Alpine Botany (August 7, 2023), our data had been re-interpreted by (Büntgen, Alpine Botany, 2023) by confusing (b) with (a). Cell death before secondary wall formation interrupts all metabolism, and thus, cannot exert a specific limitation of lignification. For the xylem to lignify, it requires a secondary cell wall in the first place. A frost damage in young tracheid cells is unsuitable for a dendrological treeline hypothesis based on a low-temperature threshold for lignification. Generally, the global pattern of treeline position is not associated with local freezing conditions. | Experimental evidence, global patterns of treeline position and climate provide no substance for a lignin limitation hypothesis of tree growth | 10.1007/s00035-023-00305-5 |
2024-02-19 | Clinically, Landrace pigs are more susceptible to porcine circovirus-associated diseases (PCVADs) than Piétrain pigs. We previously found that porcine circovirus type 2 (PCV2) can infect T-lymphoblasts. The present study examined the replication kinetics of six PCV2 strains in the lymphoblasts of Landrace and Piétrain pigs. The results showed that T-lymphoblasts from Landrace pigs are much more susceptible to PCV2 infection than those from Piétrain pigs. In addition, PCV2 replication was strain-dependent. PCV2 binding to T-lymphoblasts was partially mediated by chondroitin sulfate (CS) and dermatan sulfate (DS). Phosphacan, an effective internalization mediator in monocytes that contains several CS chains, was also demonstrated to be involved in PCV2 internalization. Viral binding and internalization were not different between the two breeds, however, the subsequent step, the disassembly was. Although inhibition of serine proteases blocked PCV2 replication in both Landrace and Piétrain pigs, this only occurred at a neutral pH in Piétrain pigs, whereas this occurred also at a low pH in Landrace. This suggested that more proteases can cleave PCV2 in Landrace lymphoblasts than in Piétrain lymphoblasts, explaining the better replication. Through co-localization studies of viral particles with endo-lysosomal markers, and quantitative analysis of organelle sizes during viral internalization, it was observed that PCV2 may exhibit a higher propensity for viral escape from late endosomes in Landrace pigs (smaller) compared to Piétrain pigs. These results provide new understandings of the different PCV2 susceptibility in Landrace and Piétrain pigs. | Molecular basis for the different PCV2 susceptibility of T-lymphoblasts in Landrace and Piétrain pigs | 10.1186/s13567-024-01275-0 |
2024-02-19 | The effect of hydrodynamic mixing on controlling Microcystis blooms or changing the algal community to diatom dominance has been widely studied; however, the effects of colonial Microcystis biomass on the development of the algal community are poorly known. Here, in order to study the changes in Microcystis blooms under continuous aeration mixing, an experiment was carried out in a greenhouse with factors of varying biomass of Microcystis and inorganic nitrogen and phosphorus enrichment in summer. There were three chlorophyll a (Chl- a ) levels in six treatments: low Chl- a level of 68.4 μg L -1 (treatments L, L-E), medium Chl- a level of 468.7 μg L -1 (treatments M, M-E), and high Chl- a level of 924.1 μg L -1 (treatments H, H-E). Treatments L-E, M-E and H-E were enriched with the same inorganic nitrogen and phosphorus nutrients. During the experiment of 30 days, the concentration of Microcystis and Chl- a decreased, and diatom Nitzschia palea cells appeared in all the treatments, which became dominant in treatments M, M-E, H and H-E, with the highest biomass of 9.41 ± 1.96 mg L -1 Nitzschia in treatment H-E on day 30. The rank order of the biomass of Nitzschia from low to high was (L = L-E) < (M = M-E) < H < H-E ( P < 0.05). In addition, Nitzschia cells were aggregates attached to Microcystis colonies in all the treatments. The results showed that the initial biomass of colonial Microcystis affected the algal shift from Microcystis dominance to Nitzschia dominance. However, the enriched inorganic nitrogen and phosphorus was beneficial for the Nitzschia increase in the high biomass treatment alone. The shift from Microcystis dominance to diatom dominance under continuous aeration mixing may be caused by low light conditions as well as the nutrients released from Microcystis decay. Moreover, the aerobic condition caused by aeration mixing maintained the colonial mucilaginous sheath to support the growth of Nitzschia cells in aggregation. This study found for the first time that Microcystis blooms could shift to diatom Nitzschia dominance in aggregates. It provided a method to control and manipulate Microcystis blooms to diatom dominance through continuous aeration mixing to proper biomass of Microcystis colonies. The shift to diatoms dominance would provide more high quality food organisms for aquaculture and be beneficial to the material cycling and energy flowing in food web dynamics. | Colonial Microcystis’ biomass affects its shift to diatom aggregates under aeration mixing | 10.1038/s41598-024-53920-5 |
2024-02-18 | Three-dimensional woven fabrics (3DWFs) possess excellent mechanical properties and structural integrity due to reinforcement in the through-thickness direction. Composites made of 3DWFs have manifested outstanding impact resistance phenomena like delamination suppression, enhanced ballistic impact, and blast performance. This study investigates the low-velocity impact (LVI) responses of 3D orthogonal and 3D angle-interlock woven fabrics of various weave architectures. Four hybridized structures were manufactured by varying the binder yarn path along the Z -axis using multiple high-performance fibres. 3DWFs were subjected to single and multiple LVI tests at an impact energy of 50J and a velocity of 3.14 ms −1 . The experimental results revealed that weave architecture, binder yarn float-length, yarn-to-yarn crossover points, stuffer binder ratio, and yarn maneuverability influence the damage tolerance of 3DWFs. Individual 3DWFs were subjected to multiple LVI events to determine how they would react up to catastrophic damage, such as complete perforation and yarn pull-out. Single and multiple LVI experiments showed that hybridized 3DWFs were more resilient to low-velocity impacts than virgin E-glass preforms. 3D orthogonal plain 1 × 1 E-glass/Kevlar (KGORPL) hybrid structure outperformed its counterparts during repeated impact episodes. | Low-velocity impact response of 3D woven solid structures for multi-scale applications: role of yarn maneuverability and weave architecture | 10.1007/s40430-024-04734-z |
2024-02-18 | Plant physiology and structure are constantly changing according to internal and external factors. The study of plant water dynamics can give information on these changes, as they are linked to numerous plant functions. Currently, most of the methods used to study plant water dynamics are either invasive, destructive, or not easily accessible. Portable magnetic resonance imaging (MRI) is a field undergoing rapid expansion and which presents substantial advantages in the plant sciences. MRI permits the non-invasive study of plant water content, flow, structure, stress response, and other physiological processes, as a multitude of information can be obtained using the method, and portable devices make it possible to take these measurements in situ, in a plant’s natural environment. In this work, we review the use of such devices applied to plants in climate chambers, greenhouses or in their natural environments. We also compare the use of portable MRI to other methods to obtain the same information and outline its advantages and disadvantages. | Towards portable MRI in the plant sciences | 10.1186/s13007-024-01152-z |
2024-02-18 | Background Infectious etiologies of lower respiratory tract infections (LRTIs) by the conventional microbiology tests (CMTs) can be challenging. Metagenomic next-generation sequencing (mNGS) has great potential in clinical use for its comprehensiveness in identifying pathogens, particularly those difficult-to-culture organisms. Methods We analyzed a total of 205 clinical samples from 201 patients with suspected LRTIs using mNGS in parallel with CMTs. mNGS results were used to guide treatment adjustments for patients who had negative CMT results. The efficacy of treatment was subsequently evaluated in these patients. Results mNGS-detected microorganisms in 91.7% (188/205) of the clinical samples, whereas CMTs demonstrated a lower detection rate, identifying microorganisms in only 37.6% (77/205) of samples. Compared to CMT results, mNGS exhibited a detection sensitivity of 93.5% and 95.4% in all 205 clinical samples and 180 bronchoalveolar lavage fluid (BALF) samples, respectively. A total of 114 patients (114/201; 56.7%) showed negative CMT results, among which 92 received treatment adjustments guided by their positive mNGS results. Notably, 67.4% (62/92) of patients demonstrated effective treatment, while 25% (23/92) experienced a stabilized condition. Subgroup analysis of cancer patients revealed that 41.9% (13/31) exhibited an effective response to treatment, and 35.5% (11/31) maintained a stable condition following medication adjustments guided by mNGS. Conclusion mNGS demonstrated great potential in identifying microorganisms of clinical significance in LRTIs. The rapid turnaround time and reduced susceptibility to the impact of antimicrobial administration make mNGS a valuable supplementary tool for diagnosis and treatment decision-making for suspected LRTIs in clinical practice. | Utilizing metagenomic next-generation sequencing for pathogen detection and diagnosis in lower respiratory tract infections in real-world clinical practice | 10.1007/s15010-024-02185-1 |
2024-02-17 | This paper focuses on the relationship between the microstructure and tensile properties of Fe–Mn–Al–C low-density high-strength steel processes by hot-rolling and air-cooling process. The microstructure analysis reveals that the combination of hot-rolling and air-cooling results in the formation of heterogeneous structures comprising different-sized γ and B2 phases in the low-density steel with the addition of nickel (Ni). The addition of Ni promotes the formation of the B2 phase and induces the pinning of B2 phase particles at the γ grain boundaries. This pinning effect effectively hinders the growth of the γ grains, leading to grain refinement. The tensile test results demonstrate that LDS-5Ni (low-density steel, LDS) exhibits excellent high strength and ductility combination, e.g., a tensile strength of 1535 MPa, yield strength of 1482 MPa, and elongation of 23.3%. These remarkable mechanical properties are primarily attributed to the combined strengthening contributions of grain refinement and duplex nano-sized second-phase precipitation hardening. | Uncovering Microstructure–Property Relationship in Ni-Alloyed Fe–Mn–Al–C Low-Density Steel Treated by Hot-Rolling and Air-Cooling Process | 10.1007/s40195-024-01666-4 |
2024-02-17 | Urban areas often have low soil water availability due to their impervious surfaces reducing rainfall infiltration. These water-limited conditions may be exacerbated by the projected increases in drought events caused by climate change. As a result, plants that grow in urban areas are vulnerable to drought stress. There are a range of practices that can be used to help mitigate drought stress, including the use of biostimulants. This study aimed to determine whether biostimulant application (1) improves plant performance and (2) mitigates the drought stress on urban plant species. To address these aims, we selected six woody and three graminoid plant species that are commonly planted in Australian urban areas and exposed them to different watering (drought-stressed, well-watered) and biostimulant (control, humic acid, protein hydrolysate, seaweed extract) treatments. We then measured their assimilation rate, growth metrics and biomass allocation. We found that drought stress reduced the assimilation rates and shoot growth of the study species. However, this did not translate into a biomass reduction because the drought-stressed plants reallocated resources towards root biomass. We found no evidence to suggest biostimulant application mitigated the impacts of drought stress on plant performance. Further, the only effect biostimulant application had on plant performance irrespective of the watering treatment was that the seaweed biostimulant increased the plant height growth of the woody species. These results show that the biostimulants used in this study will have a limited effect on the performance of plant species commonly planted in Australian urban areas. | Biostimulants do not affect the performance of urban plant species grown under drought stress | 10.1007/s11252-024-01521-5 |
2024-02-16 | Temperature is an important factor affecting the water purification performance of constructed wetland (CW). In the previous study, the combined measures of Iris sibirica and aeration at the bottom of the first quarter filtration chamber could improve the pollutant removal capacity of CW at low temperature. However, the mechanism between the combined measures of Iris sibirica and aeration on enhancing the performance of domestic sewage treatment is unclear. Our study aims to provide scientific validation for the combined measure through monitoring the concentrations of dissolved oxygen (DO), chemical oxygen demand (COD Cr ), ammonia nitrogen (NH 4 + -N), and total nitrogen (TN) along the water flow pathway of the CW and measuring the superoxide dismutase (SOD) activities of the plants and the abundance of nitrogen cycle-related microbial functional genes in the substrates of CW to explore the mechanism of combined measures promoting the removal efficiency of the CW under low-temperature stress. Results showed that aerating at the bottom of the first quarter filtration chamber increased DO concentration in the front part of the CW, which benefited the aerobic removal of pollutants and the activities of microorganisms, and the removal COD Cr and NH 4 + -N occurred mainly in the front part of the CW. SOD activities showed that I. sibirica had better resistance to low temperature than Canna indica did. The combined measures of I. sibirica and aeration activated the activities of microorganisms, increased the abundance of the denitrification process genes along the water flow pathway and formed a clear nitrification–denitrification zone in the CW, thus promoted the nitrogen removal efficiency at low temperature. Therefore, this study confirmed the feasibility of the combined measures from a mechanistic perspective. | Mechanism of Iris sibirica and aeration combination on promoting the water purification performance of constructed wetland under low temperature | 10.1007/s11356-024-32381-3 |
2024-02-16 | M-iridium (M = cobalt (Co), nickel (Ni)) bimetallic alloy catalysts with low iridium (Ir) loading of 0.3–2.0 mg·cm −2 were prepared on copper foam (CF) supports by electrodeposition. The top surface of as-deposited M-Ir catalysts was mainly composed of metallic state and oxides states, such as metallic Ir, Ni(OH) 2 or Co(OH) 2 , Co(Ir) and Ni(Ir) solid solution, Ir oxides. M-Ir catalysts with low Ir loading exhibited excellent catalytic performance. Ni 63.4 Ir 36.6 /CF catalyst with low Ir loading of 1.8 mg·cm −2 achieved a current density of 10 mA·cm 2 at an overpotential of 52 mV and a Tafel slope of 36 mV·dec −1 . Co 64.2 Ir 35.8 /CF catalyst with low Ir loading of 0.7 mg·cm −2 was uniformly scattered with small ellipsoidal particles, looking like fine fluff, requiring an overpotential of 51 mV for hydrogen evolution reaction to reach a current density of 10 mA·cm −2 , having a Tafel slope of 38 mV·dec −1 . After long-term hydrogen evolution testing, M-Ir/CF catalysts exhibited excellent electrocatalytic stability for water splitting in alkaline solution. Graphical Abstract | Structure and Electrocatalytical Properties of Electrodeposited M-Ir (M = Co, Ni) Bimetallic Alloy Catalysts with Low Ir Loading Obtained on Copper Foams for Hydrogen Evolution Reaction | 10.1007/s10562-024-04598-x |
2024-02-15 | Monochlorodifluoromethane (HCFC-22) has been identified as a significant contributor to the depletion of the Earth’s ozone layer, garnering considerable attention within the scientific community. Consequently, the investigation of Freon degradation has become a central focus of current research efforts. In this study, we opted to employ catalytic hydrolysis as it offers numerous advantages for the degradation of HCFC-22. Specifically, we prepared ZnO/ZrO 2 catalysts with hexahedral rod-like structures through citric acid complexation. We examined the impact of various preparation conditions (such as the molar ratio of ZnO to ZrO 2 , calcination temperature, and calcination time) as well as catalytic hydrolysis conditions (including the amount of catalyst, total flow rate, and catalytic hydrolysis temperature) on the hydrolysis rate of HCFC-22. Characterization of the catalysts was performed using techniques such as XRD, SEM, EDS, TG-DTG, FTIR, N 2 adsorption–desorption, CO 2 -TPD, and NH 3 -TPD. Our experimental findings revealed the optimal preparation conditions: a catalytic hydrolysis temperature of 100 °C, a molar ratio of ZnO to ZrO 2 of 0.7, a water bath temperature of 90 °C, a roasting temperature of 400 °C, and a roasting time of 4 h. At a catalytic hydrolysis temperature of 100 °C, the hydrolysis rate of HCFC-22 reached 99.81%, with the main hydrolyzed products being HCl, HF, and CO 2 . Graphical Abstract | Catalytic hydrolysis of monochlorodifluoromethane over ZnO/ZrO2 catalysts at low temperatures | 10.1007/s11356-024-32265-6 |
2024-02-15 | Low-observable technology, often known as stealth technology, hides soldiers, aircraft, ships, submarines, missiles, satellites, and ground vehicles from radar and infrared sensors (preferably invisible). Stealth coating reduces radar cross section and makes aeroplanes harder to detect. Stealth planes employ radar-absorbing polymers. Stealth technology camouflages vehicles and buildings from radar. A radar-absorbent material may alter an items radar cross section at specific radar frequencies, but it does not make it "invisible" at any frequency. Stealth technology reduces radar reflections using radar-absorbing materials and geometry. Polymer composite-based stealth are graphene, carbon black, carbon nanotubes, and carbon fibres as carbonaceous material and filler. Stealth coating resin market size is based on epoxy, polyurethane, and polyimide. It also protects automobiles against ultraviolet rays, chips, scratches. Tanks and ships employ stealth coating technology to avoid hostile radar. The coating absorbs and scatters radar radiation, hiding the device. Military aircraft uses stealth coating to avoid radar. Commercial airlines are using stealth coating technologies to improve safety and security. The coating reduces aircraft drag and weight, improving fuel economy. Stealth coating absorbs radar signals, hiding the aircraft from radar detection systems. Military and private planes utilise it for security. Stealth coating reduces radar detection by absorbing or deflecting radar emissions. Military operations need stealth and secrecy, but civilian aviation may employ this technology to avoid hijackings and identify unlicensed planes radar-absorbent polymers cover stealth aircraft. These and other design features may weaken the aircraft's radar signal. | Recent advances in stealth coating | 10.1007/s00289-024-05166-4 |
2024-02-15 | Alternatives were explored to strengthen soils in the city of Chiclayo, Peru, especially those with low plasticity and strength. The goal was to study the mechanical properties using sugarcane bagasse ash (SCBA) and high-density polyethylene (HDPE) as sustainable and cost-effective reinforcements. The ash was calcined at four different temperatures, and each sample underwent an energy X-ray fluorescence test. The sample with the highest sum of oxides was mixed with clayey soil in increasing proportions, ranging from 5 to 20% by weight. Subsequently, the SCBA proportion with the best mechanical behavior was selected, combined with increasing proportions of HDPE fibers ranging from 0.25 to 1.0% by weight. The dimensions were kept constant with a length of 25 mm and a width of 15 mm. Chemical and physical stabilization techniques were applied to the study soil. The soil mixed with ash had a direct influence on compaction test parameters and soaked California bearing ratio (CBR) test, showing a significant increase of 32.08% up to 10SCBA. However, beyond this proportion, the strength decreased below the control sample. The results indicated that clay improves its behavior and strength with a ratio of 10SCBA + 0.75HDPE, resulting in a significant increase in soaked CBR of 154%. The use of the optimum dosage of ash and fiber influences in having a subgrade layer of low and high traffic volume; in addition, it minimizes contamination problems by reducing landfills and urban deposits, contributing to environmental sustainability. | Contribution of agricultural ashes and HDPE as a waste material for a sustainable environment applied to the stabilization of a low plasticity clay soil | 10.1007/s41062-024-01372-1 |
2024-02-15 | This study presents a comparative techno-economic analysis and life cycle impact assessment of hydrogen production from the kraft lignin depolymerization (KLD) with those produced from alkaline electrolysis cell (AEC) and proton exchange membrane electrolysis (PEM). This process happens in a continuous modular flow reactor by using the phosphomolybdic acid as a redox-active catalyst and includes depolymerizing the kraft lignin, producing vanillin, acetovanillone, and hydrogen under a low-voltage condition. For the techno-economic analysis, first, the processes were modelled by using the Aspen Plus V12.1 software and then the results were transferred to Aspen Process Economic Analyzer V12 for economic evaluation. In the next step, the life cycle impact assessment was proposed by using the openLCA V1.11.0 software along with the Environmental Footprint database (MID-Point indicator), and 18 impacts were investigated. According to the techno-economic analysis, KLD exhibits a total capital cost that surpasses that of AEC and PEM by more than 18% and 11%, respectively. Furthermore, KLD’s equipment cost exceeds that of AEC and PEM by approximately 0.5% and 7%, respectively, and necessitates additional components. On the other hand, the life cycle assessment revealed that KLD yields lesser environmental impacts than AEC, while PEM exhibits the most exemplary environmental performance. | Techno-economic Analysis and Life Cycle Impact Assessment for the Valorisation of Kraft Lignin and Low-Voltage Hydrogen Production | 10.1007/s11814-024-00072-x |
2024-02-15 | Population exposure to atmospheric pollution is commonly assessed through models. This study aims to compare estimates based on a high-resolution model and actual measurements. The considered modelling system, ATMO-Street, consists of a three-layer outdoor model operating at an hourly rate with a spatial resolution of approximately 10 m. The considered measurements were made by 38 candidate citizens carrying, for 1 week, portable devices, including an AE51 aethalometer and an Antilope low-cost sensor system developed at the Scientific Institute of Public Service (ISSeP). Their data were aggregated to match the model time and space resolutions. The zone of interest is the city of Liège in Belgium during parts of the year 2019. This research sheds light on the effectiveness of the atmospheric pollution model and personal exposure assessment methods. The findings contribute to a somewhat more comprehensive understanding of our exposure to air pollution, including indoors, with potential implications for public health and environmental policy. | Mobile measurements and street-level modelling to assess outdoor and indoor personal exposure to air pollution in urban environment | 10.1007/s11869-024-01529-y |
2024-02-14 | Euphausiids are a vital component of global marine micronekton. To reveal the primary environmental factors influencing euphausiid distribution patterns in the previously overlooked low-latitude ecosystems, we investigated a large-scale community structure of euphausiids covering the North Pacific subtropical gyre (NPSG) and low-latitude eastern Indian (EI), and South Pacific Oceans (SP). A total of 41 euphausiid species from six genera were identified. Integrated primary production (PP) correlated significantly with the euphausiid abundance and species diversity and displayed the most critical influence on the variations in euphausiid community structure in low latitudes. Dissolved oxygen (DO) was the second significant environmental driver. Due to the distinct distribution patterns of euphausiid species in response to different PP and DO levels, the low-latitude euphausiid assemblages were mainly distinguished into subtropical and tropical communities. The subtropical euphausiid community associated with lower PP and higher DO demonstrated significantly lower euphausiid abundance but higher diversity than the tropical community. Euphausia brevis , E. mutica , and Stylocheiron abbreviatum , which characterize the subtropical community, appear to depend less on the phytoplanktonic prey. Euphausia diomedeae and Hansarsia gracilis , typifying the tropical population, showed stronger hypoxia tolerance. Additionally, each community was further divided into three subgroups under the influence of surface PP (subtropical: marginal NPSG, central NPSG, and austral EI-SP subgroups; tropical: the Bay of Bengal, equatorial EI, and equatorial EI-SP subgroups). These results suggested that food resource is the most important in shaping euphausiids’ community structure in an oligotrophic ecosystem with subtle hydrography gradients. | Primary productivity impacts community structure of euphausiids in the low-latitude Indian and Pacific Oceans | 10.1007/s10872-024-00713-z |
2024-02-14 | Oxide metallurgy technology uses inclusion to induce Intragranular acicular ferrite (IAF). The purpose is to refine the steel’s organization and improve its strength. However, the mechanism that inclusion induces IAF nucleation is still unclear. To solve this problem, we added TiO 2 into the low-carbon steel to investigate the ferrite nucleation mechanism induced by Ti inclusions by SEM, TEM, and EPMA. The results show that TiO 2 was added to the molten steel to form composite inclusions TiN–MnS–3MnO·Al 2 O 3 ·3SiO 2 –Ti 3 O 5 by temperature control. These inclusions are effective in inducing IAF nucleation. It is consistent with the depletion zone mechanism and low mismatch degree mechanism. It is attributed to MnS inclusions in the composite inclusions and Mn elements in the solute poverty zone. The mismatch strain between TiN–MnS–3MnO·Al 2 O 3 ·3SiO 2 –Ti 3 O 5 and IAF is less than 6%. The in-depth study of the mechanism of induced IAF nucleation by containing Ti inclusions is conducive to promoting the progress of oxide metallurgy technology. | Influence of TiO2 on Intragranular Acicular Ferrite Nucleation in Low-Carbon Steel | 10.1007/s12666-024-03264-5 |
2024-02-14 | Unraveling the genetic sources of gene expression variation is essential to better understand the origins of phenotypic diversity in natural populations. Genome-wide association studies identified thousands of variants involved in gene expression variation, however, variants detected only explain part of the heritability. In fact, variants such as low-frequency and structural variants (SVs) are poorly captured in association studies. To assess the impact of these variants on gene expression variation, we explored a half-diallel panel composed of 323 hybrids originated from pairwise crosses of 26 natural Saccharomyces cerevisiae isolates. Using short- and long-read sequencing strategies, we established an exhaustive catalog of single nucleotide polymorphisms (SNPs) and SVs for this panel. Combining this dataset with the transcriptomes of all hybrids, we comprehensively mapped SNPs and SVs associated with gene expression variation. While SVs impact gene expression variation, SNPs exhibit a higher effect size with an overrepresentation of low-frequency variants compared to common ones. These results reinforce the importance of dissecting the heritability of complex traits with a comprehensive catalog of genetic variants at the population level. A diallel hybrid panel from diverse parental natural yeast isolates is used to investigate the effects of low- frequency single nucleotide polymorphisms (SNPs) and structural variants (SVs) on gene expression variation in a population. The impact of low-frequency and structural variants is assessed using a diallel panel. Diallel SVs are fully cataloged using long-read sequencing and combined parental types. SVs contribute less than SNPs to expression variation and exhibit lower effect size. Low-frequency variants are overrepresented in associations compared to common ones. A diallel hybrid panel from diverse parental natural yeast isolates is used to investigate the effects of low- frequency single nucleotide polymorphisms (SNPs) and structural variants (SVs) on gene expression variation in a population. | Diallel panel reveals a significant impact of low-frequency genetic variants on gene expression variation in yeast | 10.1038/s44320-024-00021-0 |
2024-02-13 | The years 1958 to 1966 represent a period in which the modern hip replacement operation was developed by John Charnley at the Wrightington Hospital, based on Charnley’s concept of Low Frictional Torque Arthroplasty (LFA) in which a stainless steel femoral prosthesis with a head of only 7/8″ (22.225 mm) acts against a plastic acetabulum. The original PTFE socket material, however, was found after a couple of years to wear rapidly, with the wear debris causing an adverse tissue reaction requiring surgical revision. It was at this time that Charnley was considering discontinuing work on the hip operation, when a new plastic RH1000 (UHMWPE) was tested, against Charnley’s instructions, by his assistant Harry Craven. This material proved the turning point, and the Charnley Total Hip Arthroplasty has come to be described as the operation of the century. With little funding for materials, most of the test equipment was constructed by Craven, after scavenging from a local scrap yard. Despite the important part played by Craven, he remains largely unknown to a wider engineering audience and when mentioned is often not named, being only referred to as Charnley’s assistant. | John Charnley’s Assistant: Harry Craven and the Charnley Hip | 10.1007/s44174-024-00157-5 |
2024-02-13 | In this study, cobalt etched graphite felt electrodes were produced using a simple etching technique. It was used in combination with a solid polymer electrolyte (SPE) for the degradation of the target contaminant Orange II by Electro-Fenton (EF) technique in low conductivity water. In this method, 94% of Orange II in low conductivity water was removed in 90 min. The characterization analysis substantiates the hypothesis that the electrodes produced exhibit a three-dimensional porous structure, augmented defect concentration, and enhanced electron transfer capability. In addition, the potential reaction mechanism was inferred from the radical quenching experiments, and hydroxyl radicals (·OH) were deemed the main reactive substances. The combination of cobalt etched graphite felt electrodes with SPE demonstrates remarkable efficacy in the treatment of organic wastewater characterized by low electrical conductivity. | Cobalt etched graphite felt electrode for enhanced removal of organic pollutant in aqueous solution with a solid polymer electrolyte | 10.1007/s11356-024-32440-9 |
2024-02-13 | Background Hidradenitis suppurativa (HS), an inflammatory-based dermatological condition often associated with obesity, poses significant challenges in management. The very low-calorie ketogenic diet (VLCKD) has shown efficacy in addressing obesity, related metabolic disorders, and reducing chronic inflammation. However, its effects on HS remain underexplored. In this prospective pilot study, we aimed to investigate the impact of a 28-day active phase of VLCKD on HS in a sample of treatment-naive women with HS and excess weight. Methods Twelve women with HS and overweight or obesity (BMI 27.03 to 50.14 kg/m 2 ), aged 21 to 54 years, meeting inclusion/exclusion criteria and agreeing to adhere to VLCKD, were included. Baseline lifestyle habits were assessed. The Sartorius score was used to evaluate the clinical severity of HS. Anthropometric parameters (waist circumference, weight, height, and body mass index), body composition via bioelectrical impedance analysis, levels of trimethylamine N-oxide (TMAO), oxidized low-density lipoprotein (oxLDL), and derivatives of reactive oxygen metabolites (dROMs) were assessed at baseline and after 28 days of the active phase of VLCKD. Results VLCKD led to general improvements in anthropometric parameters and body composition. Notably, a significant reduction in the Sartorius score was observed after the intervention (Δ%: − 24.37 ± 16.64, p < 0.001). This reduction coincided with significant decreases in TMAO (p < 0.001), dROMs (p = 0.001), and oxLDL (p < 0.001) levels. Changes in the Sartorius score exhibited positive correlations with changes in TMAO (p < 0.001), dROMs (p < 0.001), and oxLDL (p = 0.002). Conclusion The 28-day active phase of VLCKD demonstrated notable improvements in HS severity and associated metabolic markers, highlighting the potential utility of VLCKD in managing HS and its association with metabolic derangements in women with overweight or obesity. | Very low-calorie ketogenic diet (VLCKD) in the management of hidradenitis suppurativa (Acne Inversa): an effective and safe tool for improvement of the clinical severity of disease. Results of a pilot study | 10.1186/s12967-024-04853-0 |
2024-02-13 | Purpose This narrative review explores available information on the process for prosthesis design and factors influencing prosthesis design decision making, to support prosthesis user’s participation in shared decision making about lower-limb prosthesis design. Recent Findings The prosthesis design process involves the fabrication of a first prosthesis and/or adjustments to a prosthesis throughout the life of the prosthesis user. Factors that influence prosthesis design decisions are extensive and may be specific to the individual prosthesis user, to prosthesis design options, the available resources, and/or the environment. Summary This review offers foundational information for a prosthesis user’s participation in shared decision making for prosthesis design, including the process of prosthesis design and factors influencing prosthesis design decisions. Future research is needed to further describe the timing of prosthesis design decisions, prosthesis design changes over time, and the role of physical and life changes of a prosthesis user on prosthesis design decisions. | A Narrative Review of Prosthesis Design Decision Making After Lower-Limb Amputation for Developing Shared Decision-Making Resources | 10.1007/s40141-024-00432-y |
2024-02-13 | Tumor immunotherapy is booming around the world. However, strategies to activate the immune system and alleviate the immunosuppression still need to be refined. Here, we demonstrate for the first time that low-intensity pulsed ultrasound (LIPUS, spatial average time average intensity ( I sata ) is 200 mW/cm 2 , frequency is 0.3 MHz, repetition frequency is 1 kHz, and duty cycle is 20%) triggers the immune system and further reverses the immunosuppressive state in the mouse models of breast cancer by irradiating the spleen of mice. LIPUS inhibited tumor growth and extended survival in mice with 4 T-1 tumors. Further studies had previously shown that LIPUS enhanced the activation of CD4 + and CD8 + T cells in the spleen and led to significant changes in cytokines, as well as induced upregulation of mRNA levels involved in multiple immune regulatory pathways in the spleen. In addition, LIPUS promoted tumor-infiltrating lymphocyte accumulation and CD8 + T cell activation and improved the dynamics of cytokines/chemokines in the tumor microenvironment, resulting in a reversal of the immunosuppressive state of the tumor microenvironment. These results suggest a novel approach to activate the immune response by irradiating the spleen with LIPUS. | Low-intensity pulsed ultrasound activated the anti-tumor immunity by irradiating the spleen of mice in 4 T-1 breast cancer | 10.1007/s00262-023-03613-1 |
2024-02-12 | The thermal conductivity of liquid trans -1,2-dichloroethene (R-1130(E)) was measured at temperatures ranging from 240 K to 340 K and pressures up to 25 MPa using a transient hot-wire instrument. A total of 447 thermal conductivity data points were measured along six isotherms. Each isotherm includes data at nine pressures, which were chosen to be at equal density increments starting at a pressure of 0.1 MPa (or slightly above the saturation pressure of R-1130(E) at temperatures above its normal boiling point) to a maximum pressure of 25 MPa. The combined expanded uncertainty of the presented experimental data is 1.4% at a 95% confidence level. The experimental data were used to evaluate the performance of an extended corresponding states (ECS) model and a residual entropy scaling (RES) model. Both models were applied in a totally predictive mode, and in a mode where the experimental data were used to tune the model parameters. A volume-translated Peng–Robinson equation of state was used to provide thermodynamic properties needed to apply both models. In a totally predictive mode, the ECS model had an average absolute relative deviation (Δ AARD ) of 6.89% relative to the experimental data with the largest deviation being − 8.33%. The RES model in a totally predictive mode showed an Δ AARD of 2.55% with the largest deviation being − 5.81%. When model parameters were fitted to the experimental data, both the ECS and the RES model represented the experimental data to within its uncertainty of 1.4%. | Thermal Conductivity of Liquid trans-1,2-Dichloroethene (R-1130(E)): Measurement and Modeling | 10.1007/s10765-024-03334-2 |
2024-02-12 | In this paper, TiO 2 catalysts doped with different Fe contents (Fe-TiO 2 catalysts) were prepared by coprecipitation method and the Fe loading capacity was optimized, and then the integrated pollutant removal experiment was conducted, in which TiO 2 doped with Fe as catalyst and H 2 O 2 as oxidant. The results show that under the condition of constant H 2 O 2 /(SO 2 + NO) molar ratio, low concentration of SO 2 can promote the oxidation and removal efficiency of NO, while high concentration of SO 2 can inhibit the removal of NO x . The pollutant removal efficiency is proportional to the amount of catalyst, liquid–gas ratio and pH value of the absorbing solution. The optimal experimental conditions are H 2 O 2 /(SO 2 + NO) molar ratio 1.5, space velocity ratio 10,000 h −1 , H 2 O 2 mass fraction 10 wt%, liquid gas ratio 10, pH 10. Correspondingly, NO oxidation efficiency reaches 88%, NO x removal efficiency 85.6%, and SO 2 is almost completely removed. The microstructure of the catalyst before and after the reaction was characterized, and the crystal structure did not change obviously. However, with the deepening of the reaction, the specific surface area of the catalyst decreases, and the catalytic effect decreases slightly. | Experimental study on integrated desulfurization and denitrification of low-temperature flue gas by oxidation method | 10.1038/s41598-024-53765-y |
2024-02-12 | The surface rust layer of ASTM A572 grade 50 high-strength low-alloy structural steel was examined under laboratory wet/dry cyclic corrosion test (CCT) conditions in a simulated polluted marine environment. According to the corrosion kinetics study, the entire corrosion process in the sample occurred in four stages, which were identified by the power law exponent, evolved phases, and electrochemical behavior of the rust layer at various stages. During the early stages of corrosion, the reduction of rust layer phases and the anodic dissolution of the steel substrate accelerated the overall corrosion rate. Variations in the corrosion rate were observed as the composition of the rust layer stabilized with increasing CCT cycle due to cracking and self-repairing of the rust layer. At higher CCT, the composition of the rust layer gradually changed from a conductive γ -FeOOH phase to a stable α -FeOOH phase. The electrochemical impedance analysis also revealed an increase in rust layer resistance as well as charge transfer resistance of side reactions such as hydrogen evolution reaction (HER). As a result, as CCT increased, corrosion resistance and thus the protective ability index increased (PAI). The defect density in the semiconducting rust layer formed at higher CCT was lower, indicating a higher level of protection. Based on the findings, a plausible mechanism of growth of the protective rust layer on the steel sample was proposed. | Understanding the Structure and Electrochemical Behavior of the Rust Layer Formed on a High-Strength Low-Alloy Structural Steel under Cyclic Exposure to Polluted Marine Atmosphere | 10.1007/s11665-024-09215-x |
2024-02-12 | Purpose Glucose not only provides energy for tumor cells, but also provides various biomolecules that are essential for their survival, proliferation and invasion. Therefore, it is of great clinical significance to understand the mechanism of how tumor cells adapt to metabolic stress and maintain their survival. The aim of this research was to study the critical role of OGT and TRIM29 O-GlcNAc modification driven adaptability of PDAC cells to low glucose stress, which might have important medical implications for PDAC therapy. Methods Western blotting, mass spectrometry and WGA-immunoprecipitation were used to examined the levels of OGT and O-GlcNAc glycosylated proteins in BxPC3 and SW1990 cells in normal culture and under glucose deprivation conditions. Crystal violet assay, flow cytometry, RIP, RT-qPCR, protein stability assay, biotin pull down were used to investigate the mechanism of OGT and TRIM29-mediated adaptive response to glucose deficiency in PDAC cells. Results The current study found that under the condition of low glucose culture, the levels of OGT and O-GlcNAc glycosylation in PDAC cells were significantly higher than those in normal culture. Moreover, the high expression of OGT has a protective effect on PDAC cells under low glucose stress. This study confirmed that there was no significant change in mRNA level and protein degradation of OGT under low glucose stress, which was mainly reflected in the increase of protein synthesis. In addition, O-GlcNAc modification at T120 site plays a critical role in the metabolic adaptive responses mediated by TRIM29. Conclusions Taken together, our study indicated that O-GlcNAcylation of TRIM29 at T120 site and OGT translation forms a loop feedback to facilitate survival of PDAC under glucose deficiency. | O-GlcNAcylation of TRIM29 and OGT translation forms a feedback loop to promote adaptive response of PDAC cells to glucose deficiency | 10.1007/s13402-023-00915-5 |
2024-02-11 | With a view to effectively control the rise in global temperatures and respond to the climate crisis, China has proposed a carbon reduction target. Among other mitigation measures, one approach for this goal is to accelerate the low-carbon transition of China’s energy-intensive industries (EIIs). Here, we propose a comprehensive framework to assess the quality of the low-carbon transition of China’s EIIs. The framework utilizes the improved Decision-Making Trial and Evaluation Laboratory (DEMATEL) method to construct a rational indicator system to guide the work. The Hasse diagram technique was chosen to rank the quality of the low-carbon transition of EIIs in China, and the results are presented in hierarchical levels. The DEMATEL method, which considers the negative influence between factors and the iterative state, can more accurately screen the critical indicators affecting changes in complex systems. In addition, the constructed indicator system is also more reasonable. The results of the assessment show that China has made certain achievements in the low-carbon transition of EIIs. Among them, the production and supply of the electricity, steam, and hot water industries have demonstrated the highest quality of low-carbon transitions. In contrast, the petroleum processing and coking industry and the nonferrous metal smelting and pressing industry have shown room for improvement. Therefore, their social acceptance and low-carbon technologies should be strengthened. The difficulties constraining the low-carbon transition of China’s EIIs should be explored in terms of the critical factors identified. Furthermore, the government should have effective and sustainable public policies and promote technological innovations for decarbonization toward China’s targets of carbon neutrality and emissions peaking. | Exploring a low-carbon transition quality assessment framework for Chinese energy-intensive industries: from carbon reduction perspective | 10.1007/s10668-024-04517-5 |
2024-02-10 | This work adopts solvothermal synthesis to fabricate PtNi nanoparticles as thin film cathodes with superior resistance against thermally driven agglomeration for low temperature solid oxide fuel cells (LT-SOFCs) operating at 450 ºC. Metal-based porous electrodes are common choices for thin film LT-SOFCs, but pure metals with high density nanoscale porosities are vulnerable to thermal agglomeration, which imposes challenges to maintaining high performance with long-term stability. Typical Pt-based thin film cathodes are previously reported to sustain a record high 600 ºC of thermal annealing with acceptable morphological stability, but the temperature is still too low for practical LT-SOFC application. In this work, the solvothermal synthesized PtNi nanoparticle thin films show superior thermal stability, sustaining 10 h of annealing at 800 ºC without significant agglomeration observed. By controlling the length of synthesis time, the particle sizes and Pt loading ratio can be varied. The cost-effective solvothermal synthesis process for the fabrication of PtNi thin film cathode is a promising way for LT-SOFC manufacturing in scale as it involves no vacuum process like typical sputtering. Graphical Abstract | Solvothermal Synthesis of PtNi Nanoparticle Thin Film Cathode with Superior Thermal Stability for Low Temperature Solid Oxide Fuel Cells | 10.1007/s40684-023-00576-7 |
2024-02-10 | Three types of catalyst samples, namely alumina carried Fe/K, zinc aluminate carried Fe/K, and (zinc aluminate + alumina) composite carried Fe/K, were prepared under calcination conditions of 350 ºC. The catalysts were characterized by XRD, ICP-OES, N 2 physical adsorption, field emission electron microscopy as well as CO 2 -TPD. The performances of the catalysts in CO hydrogenation were tested in a fixed bed reactor. The results show that under similar conversions, the C 2 = –C 4 = hydrocarbon selectivity of the prepared (zinc aluminate + alumina) composite carried Fe/K catalyst can reach 5 times that of the prepared alumina carried Fe/K catalyst and 9 times that of the prepared zinc aluminate carried Fe/K catalyst, exhibiting a typical synergistic effect based on carrier composition. The basis for this synergistic effect is the significant difference in base sites on the catalyst surface. | Carrier synergistic effect of iron based catalysts for CO hydrogenation to lower olefins | 10.1007/s11144-023-02555-0 |
2024-02-10 | The overarching aim of the present work is to explore the perception differences of stakeholders, i.e., municipalities (MN), water administrations (WS), non-governmental organizations (NGO), and universities (UN), playing vital roles in the decision mechanisms regarding one of the sustainable flood mitigation techniques, i.e., low impact development (LID) practices. As being rewarding alternative to conventional drainage techniques, four different LID strategies, i.e., green roof (GR), bioretention cells (BC), permeable pavement (PP), and infiltration trench (IT), and three of their combinations were adopted to the densely urbanized Ayamama River basin, Istanbul, Turkey. The performances of the LIDs were comprehensively evaluated based on three pillars of sustainability (i.e., social, economic, and environmental) using a hybrid multi-criteria decision-making (MCDM) framework containing the implementation of fuzzy analytical hierarchy process (fuzzy AHP) and the VIKOR (VIse KriterijumsaOptimiz acija I Kompromisno Resenje) for finding the weights of constraining criteria and prioritizing the LID scenarios, respectively. The major outcomes of this research showed that experts from MN, WS, and UN put forward the environmental dimension of sustainability, whereas respondents from NGO concentrated on the social aspect. Furthermore, MN and WS highlighted initial investment cost as the most determining criterion in optimal LID selection. On the other hand, criteria weights regarding the judgments of the experts attended from NGO revealed the significance of community resistance in specifying the optimal LID practices, while aesthetic appearance was the major concern of the academia. Hence, the present study, as an initial attempt, enabled critical standpoints for discovering perceptions of stakeholders. | Discovering the Perception Differences of Stakeholders on the Sustainable and Innovative Stormwater Management Practices | 10.1007/s11269-024-03783-2 |
2024-02-09 | Prior research has suggested that exposure to Di-(2-ethylhexyl) phthalate (DEHP) may impact lipid metabolism. However, no previous studies have investigated the relationship between DEHP exposure and newly identified lipoprotein biomarkers. Additionally, the role of lipoproteins in the link between DEHP exposure and vascular endothelial cell apoptosis remains unexplored. A total of 867 Taiwanese individuals aged 12 to 30 years were enrolled in this study to examine the correlation between urinary DEHP metabolites, lipoprotein profiles (including low-density lipoprotein cholesterol (LDL-C), small dense low-density lipoprotein cholesterol (sdLDL-C), low-density lipoprotein triglyceride (LDL-TG), high-density lipoprotein cholesterol, lipoprotein(a), apolipoprotein A1, apolipoprotein B, and triglyceride), and apoptotic microparticles (CD31+/CD42a−, CD31+/CD42a+, and CD14). We reported elevated levels of mono-2-ethylhexyl phthalate (MEHP) that were found to be positively associated with higher levels of lipoproteins [LDL-C, sdLDL-C, LDL-TG, and lipoprotein(a)] with P values less than 0.001, less than 0.001, 0.010, and 0.006, respectively, as well as three types of apoptotic microparticles (all P values < 0.001). Additionally, increased levels of LDL-C, sdLDL-C, LDL-TG, and triglycerides were linked to higher levels of ln-CD31+/CD42a− with P values less than 0.001, less than 0.001, 0.002, and 0.014, respectively. Furthermore, increased levels of LDL-C and sdLDL-C were also linked to higher levels of ln-CD31+/CD42a+ with P values less than 0.001 and 0.001, respectively. The structural equation model demonstrated that MEHP had a direct correlation with CD31+/CD42a− and was also indirectly associated with it through LDL-C, sdLDL-C, and LDL-TG. Furthermore, MEHP was directly linked with CD31+/CD42a+, and indirectly associated with it through LDL-C and sdLDL-C. In conclusion, these novel findings have important implications for our understanding of the effects of DEHP exposure on cardiovascular health. The identification of DEHP as a contributor to lipoprotein alterations and apoptosis in vascular endothelial cells provides a valuable foundation for future research in the field of environmental cardiology. Further research is necessary to determine whether a causal relationship exists. | The Association Among Urinary Di-(2-ethylhexyl) Phthalate Metabolites, Serum Lipid Profiles, and Serum Apoptotic Microparticles in a Young Taiwanese Population | 10.1007/s12403-024-00626-8 |
2024-02-09 | The lubricating material near the friction area plays a crucial role for many friction components. In this study, utilizing the advantages of 3D printing layer-by-layer accumulation, a lubricating layer containing microcapsules was constructed on the surface of the matrix to achieve active lubrication on-demand. It was found that using on-demand lubrication printing scheme allowed equal amounts of microcapsules to provide superior lubrication compared to integral lubrication. The coefficient of friction (COF) of the composites with on-demand lubrication was reduced to 0.08, with a decrease of 89.6%, compared to the uniform distribution of the conventional lubricant, with no significant reduction in the compressive strength and a reduction in the wear rate by two orders of magnitude; The on-demand lubricated composite has a friction coefficient as low as 0.057 and a compressive strength of about 160 MPa when destroyed. It was demonstrated that the part containing microcapsules on the surface acted as a lubricant, and the part without microcapsules acted as load-bearing. Therefore, the composite material had good mechanical properties and excellent self-lubricating ability. This study pioneered the application of microcapsules in light-curing 3D printing, compared the effects of various printing schemes and different additions of microcapsules added into the photosensitive resins, and provided ideas for the preparation of friction parts with better overall performance. | 3D Printing Composite with Microcapsules for On-Demand Lubrication | 10.1007/s11249-024-01830-y |
2024-02-09 | We show that DSSYK amplitudes are reproduced by considering the quantum mechanics of a constrained particle on the quantum group SU q (1 , 1). We construct its left-and right-regular representations, and show that the representation matrices reproduce two-sided wavefunctions and correlation functions of DSSYK. We then construct a dynamical action and path integral for a particle on SU q (1 , 1), whose quantization reproduces the aforementioned representation theory. By imposing boundary conditions or constraining the system we find the q -analog of the Schwarzian and Liouville boundary path integral descriptions. This lays the technical groundwork for identifying the gravitational bulk description of DSSYK. We find evidence the theory in question is a sine dilaton gravity, which interestingly is capable of describing both AdS and dS quantum gravity. | Dynamical actions and q-representation theory for double-scaled SYK | 10.1007/JHEP02(2024)067 |
2024-02-08 | As interest in pin perovskite solar cells (PeSCs) capable of low temperature solution process increases, research on the low temperature solution processable hole transport layer (HTL) is emerging as an important issue. Although a solution processed nickel oxide (NiO) has been spotlighted as an optimal HTL, high temperature post treatment over 250 ℃ is required for suff cient device performance. In this study, NiO film fabricated from presynthesized NiO nanoparticle dispersion is investigated as HTLs and their interface is modified with [4-(3,6 dimethyl-9 H carbazol 9 yl)butyl]phosphonic acid (Me 4PACz) to demonstrate highly efficient PeSCs processed at ~100 ℃. The combination of the low temperature processed NiO with optimal thickness (~10 nm) and Me 4PACz exhibits higher efficiency of 17.4% comparing to bare NiO based device showing 12.4%. Me 4PACz modification on NiO results in an improved energy level alignment with perovskite and more hydrophobic NiO/Me 4PACz induces excellent perovskite layer with larger grain and high crystallinity. Furthermore, the NiO/Me-4PACz-based PeSC maintains 83% of their initial efficiency after 140 days in air. This result shows that our low temperature solution processed NiO/Me 4PACz can be a promising candidate as HTLs even in terms of stability. | Modification of low temperature solution–processed NiO with Me-4PACz for efficient and air-stable p-i-n perovskite solar cells | 10.1007/s10008-024-05823-8 |
2024-02-08 | The medicinal herb Artemisia annua L . is prized for its capacity to generate artemisinin, which is used to cure malaria. Potentially influencing the biomass and secondary metabolite synthesis of A. annua is plant nutrition, particularly phosphorus (P). However, most soil P exist as insoluble inorganic and organic phosphates, which results to low P availability limiting plant growth and development. Although plants have developed several adaptation strategies to low P levels, genetics and metabolic responses to P status remain largely unknown. In a controlled greenhouse experiment, the sparingly soluble P form, hydroxyapatite (Ca 5 OH(PO 4 ) 3 /CaP) was used to simulate calcareous soils with low P availability. In contrast, the soluble P form KH 2 PO 4 /KP was used as a control. A. annua ’s morphological traits, growth, and artemisinin concentration were determined, and RNA sequencing was used to identify the differentially expressed genes (DEGs) under two different P forms. Total biomass, plant height, leaf number, and stem diameter, as well as leaf area, decreased by 64.83%, 27.49%, 30.47%, 38.70%, and 54.64% in CaP compared to KP; however, LC–MS tests showed an outstanding 37.97% rise in artemisinin content per unit biomass in CaP contrary to KP. Transcriptome analysis showed 2015 DEGs (1084 up-regulated and 931 down-regulated) between two P forms, including 39 transcription factor (TF) families. Further analysis showed that DEGs were mainly enriched in carbohydrate metabolism, secondary metabolites biosynthesis, enzyme catalytic activity, signal transduction, and so on, such as tricarboxylic acid (TCA) cycle, glycolysis, starch and sucrose metabolism, flavonoid biosynthesis, P metabolism, and plant hormone signal transduction. Meanwhile, several artemisinin biosynthesis genes were up-regulated, including DXS , GPPS , GGPS , MVD , and ALDH , potentially increasing artemisinin accumulation. Furthermore, 21 TF families, including WRKY, MYB, bHLH, and ERF, were up-regulated in reaction to CaP, confirming their importance in P absorption, internal P cycling, and artemisinin biosynthesis regulation. Our results will enable us to comprehend how low P availability impacts the parallel transcriptional control of plant development, growth, and artemisinin production in A. annua . This study could lay the groundwork for future research into the molecular mechanisms underlying A. annua ’s low P adaptation. | Genetics and metabolic responses of Artemisia annua L to the lake of phosphorus under the sparingly soluble phosphorus fertilizer: evidence from transcriptomics analysis | 10.1007/s10142-024-01301-6 |
2024-02-07 | The use of Ni nanopastes for joining applications offers advantages over other methods. However, since it is based on solid-state processes, a pressure must be applied during the joining process, which represents a challenge. To overcome this, a novel concept is presented in this work, which introduces a low-melting additive to the Ni nanopaste. A liquid phase provides the potential to achieve a joint seam formation with both a reduced porosity and better adhesion to the base material without technical pressure during the process. In a comprehensive selection, elements such as Mg, Al, Ge, In, Sn, and Pr are identified as suitable additives. Their properties in binary phase systems with nickel are discussed. A modified Ni nanopaste with Ge as additive was used in promising initial experiments, which is a good starting point for further investigations. | Composition design for modified nickel nanopastes containing a low-melting element as additive for pressureless nanojoining | 10.1007/s40194-024-01699-4 |
2024-02-07 | Poly(N-vinylcaprolactam -co- hydroxyethyl acrylate -co- phenyl vinyl sulfide) (poly(VC -co- HEA -co- PVS)) and poly(N-vinylcaprolactam -co- N-vinylpyrrolidone -co- phenyl vinyl sulfide) (poly(VC -co- VP -co- PVS)) were synthesized as thermos-sensitive oxidizable terpolymers. The copolymerization was confirmed by the 1 H-NMR and FT-IR spectroscopy. VC homopolymer exhibited its lower critical solution temperature (LCST) around 32 ℃. The copolymerization of HEA with VC and of VP with VC decreased and increased the LCST of VC homopolymer, respectively. The inclusion of PVS (an oxidizable monomer) in the copolymers decreased the LCST. The PVS of the copolymers could be oxidized by H 2 O 2 , solution (0.1%), evidenced by 1 H-NMR spectroscopy. Upon the oxidation, the LCST of poly(VC -co- PVS) and poly(VC -co- HEA -co- PVS) increased markedly possibly due to an increase in the hydrophilicity of PVS. However, the LCST of poly(VC -co- VP -co- PVS) was not markedly affected by the oxidation. The interface activity of poly(VC -co- PVS) and poly(VC -co- HEA -co- PVS) slightly decreased but that of poly(VC -co- VP -co- PVS) markedly increased by the oxidation. The critical micelle concentration of the copolymers was determined by a fluorescence method, and it was 0.087 to 0.105 mg/mL. The micelles of the copolymers were found as circular objects on a transmission electron microscope. The mean hydrodynamic diameters of micelles were 107.4 to 471.6 nm, depending on the polymer composition. The PVS-containing copolymers formed larger micelles than VC homopolymer, possibly because the monomer could enhance an intermolecular hydrophobic interaction due to its phenyl group. | Preparation of Thermo-sensitive oxidizable N-vinylcaprolactam-based terpolymers and their self-assembling property | 10.1007/s10965-024-03909-5 |
2024-02-07 | Background Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa , Escherichia coli, Streptococcus pneumoniae and Staphylococcus aureus are major bacterial causes of lower respiratory tract infections (LRTIs) globally, leading to substantial morbidity and mortality. The rapid increase of antimicrobial resistance (AMR) in these pathogens poses significant challenges for their effective antibiotic therapy. In low-resourced settings, patients with LRTIs are prescribed antibiotics empirically while awaiting several days for culture results. Rapid pathogen and AMR gene detection could prompt optimal antibiotic use and improve outcomes. Methods Here, we developed multiplex quantitative real-time PCR using EvaGreen dye and melting curve analysis to rapidly identify six major pathogens and fourteen AMR genes directly from respiratory samples. The reproducibility, linearity, limit of detection (LOD) of real-time PCR assays for pathogen detection were evaluated using DNA control mixes and spiked tracheal aspirate. The performance of RT-PCR assays was subsequently compared with the gold standard, conventional culture on 50 tracheal aspirate and sputum specimens of ICU patients. Results The sensitivity of RT-PCR assays was 100% for K. pneumoniae , A. baumannii , P. aeruginosa , E. coli and 63.6% for S. aureus and the specificity ranged from 87.5% to 97.6%. The kappa correlation values of all pathogens between the two methods varied from 0.63 to 0.95. The limit of detection of target bacteria was 1600 CFU/ml. The quantitative results from the PCR assays demonstrated 100% concordance with quantitative culture of tracheal aspirates. Compared to culture, PCR assays exhibited higher sensitivity in detecting mixed infections and S. pneumoniae . There was a high level of concordance between the detection of AMR gene and AMR phenotype in single infections. Conclusions Our multiplex quantitative RT-PCR assays are fast and simple, but sensitive and specific in detecting six bacterial pathogens of LRTIs and their antimicrobial resistance genes and should be further evaluated for clinical utility. | Development and validation of multiplex real-time PCR for simultaneous detection of six bacterial pathogens causing lower respiratory tract infections and antimicrobial resistance genes | 10.1186/s12879-024-09028-2 |
2024-02-06 | It is crucial to investigate the characteristics of fire danger in the Beijing-Tianjin-Hebei (BTH) region to improve the accuracy of local fire danger monitoring, forecasting, and management. With the use of instrumental observation data from 173 national meteorological stations in the BTH region from 1991 to 2020, the fire weather index (FWI) is first calculated in this study, and its spatiotemporal characteristics are analyzed. The high- and low-fire danger periods based on the FWI occur in April and August, respectively, with significant decreasing and increasing trends throughout the BTH region over the past 30 years. Next, the contributions of different meteorological factors to the FWI are quantified via a detrending technique. Most regions are affected by precipitation during the high-fire danger period. Both the maximum surface air temperature (Tmax) and precipitation, however, notably contribute to the FWI trend changes during the low-fire danger period. Then, we assess the linkage with atmospheric circulation. Abundant water vapor from the Northwest Pacific and local upward motion jointly lead to increased precipitation and, as a consequence, a decreased FWI during the high-fire danger period. A lack of water vapor from the boreal zone and local downward movement could cause adiabatic subsidence and hence, amplify the temperature and FWI during the low-fire danger period. In contrast to shared socioeconomic pathway (SSP) 585, in which the FWI in the BTH region exhibits a north–south dipole during the low-fire danger period, SSP245 yields an east–west dipole during the low-fire danger period. This study reveals that there is a higher-than-expected probability of fire danger during the low-fire danger period. Therefore, it is essential to intensify research on the fire danger during the low-fire danger period to improve our ability to predict summer fire danger. | Variation in fire danger in the Beijing-Tianjin-Hebei region over the past 30 years and its linkage with atmospheric circulation | 10.1007/s10584-024-03689-3 |
2024-02-06 | Excessive discharge of pharmaceutical wastes into the surface water causes harmful effect on environment, so its removal has aroused much attention in recent years. This study investigated the potential of raw eggshell as a low cost adsorbent on the removal of tadalafil by adsorption experiments. Characterization of adsorbent was investigated using Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and X-ray diffraction (XRD). To comprehensively evaluate the independent and interacting effects of several process factors, such as pH, temperature, and amount of adsorbent, Box-Behnken design was used. According to results of variance analysis (ANOVA) it was concluded that the second-order model had strong statistical relevance and was characterized by a high coefficient of determination (R 2 ) value. It was clear from the experimental results that as the pH level and adsorbent amount were raised, so was the removal efficiency. At pH 5, 25 °C, and 7.5 g/100 mL of adsorbent, the greatest removal efficiency of 72.9% was attained. Furthermore, the analysis of equilibrium data showed that, in comparison to the Langmuir isotherm model, the Freundlich isotherm model offered a better fit for dye removal. Furthermore, the adsorption kinetic was also evaluated and it was obtained the adsorption followed by pseudo second order model for the tadalafil removal onto eggshell. | Response surface methodology for optimizing adsorption process parameters for tadalafil removal by raw eggshell | 10.1007/s13399-024-05380-0 |
2024-02-06 | The present study aimed to investigate the efficiency of biosynthesized zinc oxide nanoparticles in fungal supernatant grown in kitchen wastewater with microelectronic sludge (FKMW-ZnO NPs) to be used in the degradation low-density polyethylene (LDPE) in aqueous solution. The photocatalysis process was optimized using response surface methodology as a function of four independent factors included LDPE concentrations $$\left( {x_{1} } \right)$$ x 1 (100–500 mg/100 mL), FKMW-ZnO NPs concentrations $$\left( {x_{2} } \right)$$ x 2 (10–100 mg/100 mL), time $$\left( {x_{3} } \right)$$ x 3 (1–6 h) and pH $$\left( {x_{4} } \right)$$ x 4 (4–9). The maximum photocatalysis of LDPE was 45.43% optimized with 229.96 mg LDPE/100 mL, 100 mg FKMW-ZnO NPs/100 mL at pH 7 and after one hour with R 2 is 0.7377. Microstructure and chemical structure analysis showed a significant change in the chemical structure of the photocatalysis of LDPE because of FKMW-ZnO NPs. The mathematical predication model using a radial basis function neural network ensemble system (RBFNNES) provided more accurate prediction model 89.2857% with R 2 = 0.8688. However, RBFNNES revealed that FKMW-ZnO NPs and LDPE have unstable behaviour towards the investigated factor and the interaction between these factors where the error was increasing with the increasing the time of neural network which indicates that the obtained efficiency in the optimization study might be not applicable in the large scales or in different environmental factors. More optimization with a wide range of factors is required to understand the applicability of FKMW-ZnO NPs in remediation of LDPE in the environment. Graphical Abstract | Photocatalysis of low-density polyethylene using FKMW-ZnO NPs: optimization and predication model using a radial basis function neural network ensemble system | 10.1007/s10098-023-02718-6 |
2024-02-06 | Background The relationship between induction and recurrence due to atrial tachycardia (AT) and left atrial (LA) matrix progression after atrial fibrillation (AF) ablation remains unclear. Methods One hundred fifty-two consecutive patients with paroxysmal and persistent AF who underwent pulmonary vein isolation (PVI) and cavo-tricuspid isthmus (CTI) ablation and achieved sinus rhythm before the procedure were classified into three groups according to the AT pattern induced after the procedure: group N (non-induced), F (focal pattern), and M (macroreentrant pattern) in 3D mapping. Results The total rate of AT induction was 19.7% (30/152) in groups F ( n = 13) and M ( n = 17). Patients in group M were older than those in groups N and F, with higher CHADS 2 /CHA 2 DS 2 -VASc values, left atrial enlargement, and low-voltage area (LVA) size of LA. The receiver operating characteristic curve determined that the cut-off LVA for macroreentrant AT induction was 8.8 cm 2 (area under the curve [AUC]: 0.86, 95% confidence interval [CI]: 0.75–0.97). The recurrence of AT at 36 months in group N was 4.1% (5/122), and at the second ablation, all patients had macroreentrant AT. Patients with AT recurrence in group N had a wide LVA at the first ablation, and the cut-off LVA for AT recurrence was 6.5 cm 2 (AUC 0.94, 95%CI 0.88–0.99). Adjusted multivariate analysis showed that only LVA size was associated with the recurrence of macroreentrant AT (odds ratio 1.21, 95%CI 1.04–1.51). Conclusions It is important to develop a therapeutic strategy based on the LVA size to suppress the recurrence of AT in these patients. Graphical abstract | Association between left atrial low-voltage area and induction and recurrence of macroreentrant atrial tachycardia in pulmonary vein isolation for atrial fibrillation | 10.1007/s10840-024-01760-8 |
2024-02-05 | In this paper, aliphatic polycarbonate (APC) was successfully prepared from low-boiling organic matter and aliphatic diols in waste electrolyte by ester exchange reaction and polycondensation reaction, and the process conditions were optimized to investigate the effects of catalyst type and dosage, type of aliphatic diol raw material, transesterification temperature, polycondensation temperature, polycondensation time, and polycondensation vacuum degree on the yield and molecular weight of the product. The structure and properties of the product APC were tested using Fourier transform infrared spectrometer (FTIR), H nuclear magnetic resonance spectra ( 1 HNMR), differential scanning calorimetry (DSC), thermal gravity analysis (TG), gel permeation chromatography (GPC), and electronic universal testing machine were used to test the structure and properties of the product APC. The results showed that the lithium biimidazole catalyzed the best effect and the synthesized APC had the correct structure and great properties, including good thermal stability, mechanical properties, and degradation properties. The product was degraded under the action of enzyme for 12 days, and its degradation rate could reach more than 98%, meeting the use standard of degradable polycarbonate. It has a good application prospect. Graphical Abstract | Preparation of degradable polycarbonate from low boiling point organic matter of waste electrolyte | 10.1007/s10163-024-01889-8 |
2024-02-05 | The characteristic behavior of magnetic remanence correlated with mineralogical textures and composition was observed using low-temperature magnetometry, microscopy, and chemical analysis of three isocubanite samples collected from hydrothermal deposits in the Okinawa Trough and a sample transformed from natural cubanite via heating. Both zero-field remanence acquired at 5 K and field cooling remanence acquired at 300–5 K of all samples sharply decreased with increasing temperature at approximately 100 K. In addition, low-temperature cycling of isothermal remanence at 300 K exhibited a transition at approximately 100 K; remanence increased with decreasing temperature and vice versa. The intensity of remanence at low temperature and sharpness of the transition varied across samples with different compositions and microscopic textures, that is, the presence or absence of chalcopyrite lamellae and their widths. The sample obtained from a hydrothermal chimney, in which the magnetic transition was most clearly observed, was also subjected to X-ray diffraction, Mössbauer spectroscopy, electrical resistivity, and magnetic hysteresis measurements. The obtained results were generally consistent with those reported previously for unnamed mineral CuFe 3 S 4 with an ordered cation arrangement. The low-temperature magnetic behavior of isocubanite possibly depends on the degree of cation ordering and can be regarded as an indicator of chemical composition and cooling history. Therefore, low-temperature magnetometry is useful for the detection of isocubanite and a potentially powerful technique for the prompt estimation of its composition and texture, contributing to our understanding of the formation process of hydrothermal deposits. | Low-temperature magnetic behavior of isocubanite from seafloor hydrothermal deposits in the Okinawa Trough | 10.1007/s00269-023-01264-3 |
2024-02-05 | Synthetic dyes, especially azo dyes, are extensively used in textile industries and these are also perceived as the major challenge to remove the toxicity caused by them in an aqueous system. There are many technologies like membrane filtration, photocatalysis, adsorption, flocculation, ozonation, reverse osmosis, chemical oxidation, and coagulation. Among several technologies, Adsorption is the most promising method for treating wastewater. In the present study, Coconut husk (CH) was selected as a biomass which was converted into carbonaceous biochar. CH was doped with transition metal-cobalt in a ratio of (10:1) and pyrolyzed at 600 °C. The Cobalt @ coconut husk biochar (Co@CHBc) was analyzed by FTIR, FESEM, and XRD spectroscopy. The maximum removal of methyl orange (MO) dye was 99% which was observed at pH = 4.0, contact time of 30 min, adsorbent dosage of 1 g, and initial dye concentration of 20 mg L −1 at room temperature. The removal of MO dye was achieved in a shorter time as compared to the previous studies mentioned in the literature. Thermodynamic studies suggest that the adsorption is endothermic for MO dye removal. The pseudo-second-order model was observed to be the most suitable for the adsorption data having regression coefficients (R 2 ) 0.996, and the Langmuir isotherm was the finest fit for the equilibrium data with R 2 0.9958. The Co@CHBc demonstrated a remarkable regeneration capacity up to 5 cycles, after being subjected to 0.1 M NaOH. A real dye sample experiment was conducted to validate the applicability of the Co@CHBc. A proposed reaction mechanism was designed on model analysis based. Using the GCMS technique, it was proved that the MO dye was broken down into non-hazardous components like carbon dioxide, water, and sulfate after adsorption. The Co@CHBc provides an innovative and environmentally friendly method for removing dyes from wastewater, within the circular economy framework. Thus, the newly synthesized Co@CHBc may be an excellent choice for treating wastewater containing dyestuffs. | Encapsulated cobalt-doped coconut husk biochar (Co@CHBc) for the remediation of anionic dye from wastewater | 10.1007/s13399-024-05378-8 |
2024-02-05 | Polymer flooding is one of the most effective tertiary oil recovery technologies, which can significantly improve the sweep efficiency of the reservoir by injecting high-viscosity polymer solution. However, Conventional polymers are difficult to inject, easy to degrade after shearing, cause plugging in low-permeability reservoirs, functional monomers have potential environmental pollution risks, and limit its industrial application. In recent years, more and more attention has been paid to the development of adaptive supramolecular oil displacement materials from bio-based materials. Here, the bases of guanine and cytosine from ribonucleic acid are grafted onto polyacrylamide. With a multi-supramolecular interactions through synergistic hydrogen bonding and hydrophobic interactions, HPAM-C≡G-HPAM with excellent injectivity and high viscosity are developed to improve the recovery of low permeability reservoirs. Subsequently, HPAM-C≡G-HPAM was characterized by FT-IR, NMR, ESEM and DLS. The rheological test results show that the tackifying ability of the supramolecular system is much higher than that of polyacrylamide with the same molecular weight and has excellent shear resistance. In the laboratory core displacement experiment, the injection pressure of HPAM-C≡G-HPAM in low permeability core is only 1/3 of that of polyacrylamide with the same viscosity, and the oil recovery can be increased by 16.31%, The oil recovery can be increased by 10% under high temperature and high salinity conditions. Accordingly, HPAM-C≡G-HPAM has the potential to greatly enhance oil recovery in low permeability reservoirs. | Bioinspired Self-Assembly Polymer Based on Nucleobase for Enhanced Oil Recovery | 10.1007/s10924-023-03176-3 |
2024-02-05 | Based on historical developments and the current state of the art in gas-phase transmission electron microscopy (GP-TEM), we provide a perspective covering exciting new technologies and methodologies of relevance for chemical and surface sciences. Considering thermal and photochemical reaction environments, we emphasize the benefit of implementing gas cells, quantitative TEM approaches using sensitive detection for structured electron illumination (in space and time) and data denoising, optical excitation, and data mining using autonomous machine learning techniques. These emerging advances open new ways to accelerate discoveries in chemical and surface sciences. Graphical abstract | Quantitative gas-phase transmission electron microscopy: Where are we now and what comes next? | 10.1557/s43577-023-00648-8 |
2024-02-05 | Autosomal dominant variants in LRP10 have been identified in patients with Lewy body diseases (LBDs), including Parkinson’s disease (PD), Parkinson’s disease-dementia (PDD), and dementia with Lewy bodies (DLB). Nevertheless, there is little mechanistic insight into the role of LRP10 in disease pathogenesis. In the brains of control individuals, LRP10 is typically expressed in non-neuronal cells like astrocytes and neurovasculature, but in idiopathic and genetic cases of PD, PDD, and DLB, it is also present in α-synuclein-positive neuronal Lewy bodies. These observations raise the questions of what leads to the accumulation of LRP10 in Lewy bodies and whether a possible interaction between LRP10 and α-synuclein plays a role in disease pathogenesis. Here, we demonstrate that wild-type LRP10 is secreted via extracellular vesicles (EVs) and can be internalised via clathrin-dependent endocytosis. Additionally, we show that LRP10 secretion is highly sensitive to autophagy inhibition, which induces the formation of atypical LRP10 vesicular structures in neurons in human-induced pluripotent stem cells (iPSC)-derived brain organoids. Furthermore, we show that LRP10 overexpression leads to a strong induction of monomeric α-synuclein secretion, together with time-dependent, stress-sensitive changes in intracellular α-synuclein levels. Interestingly, patient-derived astrocytes carrying the c.1424 + 5G > A LRP10 variant secrete aberrant high-molecular-weight species of LRP10 in EV-free media fractions. Finally, we show that this truncated patient-derived LRP10 protein species (LRP10 splice ) binds to wild-type LRP10, reduces LRP10 wild-type levels, and antagonises the effect of LRP10 on α-synuclein levels and distribution. Together, this work provides initial evidence for a possible functional role of LRP10 in LBDs by modulating intra- and extracellular α-synuclein levels, and pathogenic mechanisms linked to the disease-associated c.1424 + 5G > A LRP10 variant, pointing towards potentially important disease mechanisms in LBDs. Graphical abstract | LRP10 and α-synuclein transmission in Lewy body diseases | 10.1007/s00018-024-05135-0 |
2024-02-05 | Spinal cord injury (SCI) results in stalled motor function recovery under the chronic phase. One of the reasons due to the presence of ongoing inflammation. Therefore, regulating the status of immune cells may help reopen the window for neural repair, which represents a potential therapeutic target. In this study, we aimed to investigate whether this could be achieved in mice with cervical 5 crush CSCI (4 W) by utilizing a concentration of 0.5 mg/kg of lipopolysaccharide (LPS) to stimulate microglia/macrophages. Additionally, the mice underwent rehabilitation training for another 6 weeks. Our results showed that systemic injection of LPS enhanced the effects of forelimb rehabilitation training, as evaluated through single pellet grasping (SPG). Electrophysiological studies revealed the restoration of cortical drive to the injured side’s forelimb muscles in the training combined with LPS group. Tract tracing studies demonstrated the reconstruction of cortical innervation to the cervical spinal cord. Furthermore, the levels of pro-inflammatory phenotype markers, such as inducible nitric oxide synthase (INOS) and CD68, decreased, while the expression of anti-inflammatory phenotype markers, including arginase 1 (ARG-1) and CD206, increased. Importantly, this phenotypic switch in microglia/macrophages was accompanied by an increase in phagocytic activity markers as indicated by BODIPY + IBA1 + staining. Collectively, our data suggests that low-dose LPS improves the effects of rehabilitation training by regulating the phenotypic transformation of microglia/macrophages in CSCI. This study provides a fresh perspective and intervention direction for the clinical treatment of chronic spinal cord injuries. | Low-Dose LPS Modulates Microglia/Macrophages Phenotypic Transformation to Amplify Rehabilitation Effects in Chronic Spinal Cord Injured (CSCI) Mice | 10.1007/s12035-024-03979-y |
2024-02-05 | Atherosclerosis is initiated by vascular endothelial dysfunction, and low-shear stress (LSS) of blood flow is a key factor leading to endothelial dysfunction. Growing evidence suggests that endothelial cell pyroptosis plays an important role in the development of atherosclerosis. Studies have shown that low-shear stress can induce endothelial cell pyroptosis, but the exact mechanism remains unclear. Our experiments demonstrated that low-shear stress induced endothelial cell pyroptosis and the phosphorylation of IκB kinase ε (IKKε). IKKε knockdown not only significantly attenuated atherosclerosis lesions of aortic arch areas in ApoE −/− mice fed with high cholesterol diets, but also markedly reduced endothelial cell pyroptosis and NLRP3 expression triggered by low-shear stress. Further mechanism studies showed that IKKε promoted the expression of NLRP3 via activating signal transducer and activator of transcription 1 (STAT1) and the subsequent binding of STAT1 to NLRP3 promoter region. These results suggest that low-shear stress plays a pro-atherosclerotic role by promoting endothelial cell pyroptosis through the IKKε/STAT1/NLRP3 pathway, which provides new insights into the formation of atherosclerosis. | Low-Shear Stress Promotes Atherosclerosis via Inducing Endothelial Cell Pyroptosis Mediated by IKKε/STAT1/NLRP3 Pathway | 10.1007/s10753-023-01960-w |
2024-02-05 | The Middle Jurassic Walloon Subgroup coals in Australia’s Surat Basin are extremely rich in low-medium rank coal seam gas (CSG) resources, making it one of the world’s most productive CSG development basins. The desorption, diffusion and seepage behaviors of CSG are remarkably influenced by the pore–fracture structure characteristics of coals; therefore, their detailed characterizations are greatly significant for CSG exploration and development. There are, however, currently few researches on the pore–fracture structure characteristics of Surat Basin coals. Thus, 12 low-medium rank coals ( $${\overline{\text{R}}}$$ R ¯ r: 0.42–0.60%) from the Walloon subgroup of Eastern Surat Basin were obtained for this study, and then coal petrology analyses, field emission scanning electron microscopy and nuclear magnetic resonance (NMR) experiments were performed on these samples. The results show that the organic macerals of Surat coals are dominated by vitrinite, followed by liptinite, and the inertinite is generally rare. The average porosity, movable porosity and movable water saturation of the coal samples were 5.08%, 1.01% and 22.47%, respectively. The coal samples’ pore–fracture structure was characterized by an overwhelming predominance of MIT (micropores and transition pore) and relatively less developed ME (mesopore) and MAF (macropore and fracture), with average volume proportions of 74.58%, 14.06% and 11.36%, respectively. The movable porosities of different pore–fracture structure types were obtained, and the average values were presented as MAF > ME > MIT. The NMR experiments showed that the average movable spaces in the MIT, ME and MAF of the coal samples were 6.6%, 41.8% and 97.9%, respectively. The pore–fracture structure of the sampled coals was influenced by coal maturity, as well as the coal macerals. The coal facies have some impacts on the porosities of coal samples, and the coals with higher texture preservation index and vegetation index, and lower gelation index overall have higher porosities. | Pore–Fracture Structure Characteristics of Low-Medium Rank Coals from Eastern Surat Basin by FE-SEM and NMR Experiments | 10.1007/s11053-023-10304-2 |
2024-02-05 | Negative stiffness mechanisms can improve low-frequency vibration isolation performance and have been widely used in the vibration isolation of precision equipment. However, the negative stiffness mechanism usually introduces a nonlinear stiffness, resulting in a nonlinear response and worsening the vibration isolation performance, especially under large amplitude vibration. In this paper, an electromagnetic spring with linear negative stiffness (ESLNS) is proposed, in which the antagonistic ampere forces of the energized coils are used to generate negative stiffness within a long linear stroke. The magnetic field distribution is improved through the design of the magnetic circuit, thereby increasing the stiffness generation efficiency. The stiffness can be adjusted bidirectionally by current within the range of positive and negative stiffness. An electromagnetic stiffness model was established based on the equivalent magnetic circuit method. Experimental measurements verified the accuracy of the model and proved the linearity of the electromagnetic spring. A vibration isolator with high static and low dynamic stiffness (HSLDS) based on the ESLNS is designed and tested. The experimental results prove that the introduction of the ESLNS can effectively expand the isolation frequency band without changing the equilibrium position. Moreover, the vibration isolator with ESLNS does not produce nonlinear response. The proposed electromagnetic spring with linear negative stiffness extends the application range of HSLDS isolators to a large amplitude vibration environment. | High-static-low-dynamic stiffness isolator based on an electromagnetic negative stiffness spring with long linear stroke | 10.1007/s11431-023-2586-y |
2024-02-04 | A medium-carbon low-alloy steel with designed chemical composition was investigated. The steel exhibits an excellent product of strength and elongation value of 31,832 MPa% through quenching and partitioning treatment, with a tensile strength of 1413 MPa and elongation of 22%. X-ray diffraction analysis and transmission electron microscopy characterizations confirm that the retained austenite in the specimens undergoes stress-induced phase transformation to the martensite and hexagonal phases, namely the transformation-induced plasticity (TRIP) effect is triggered. This TRIP effect, triggered by the stress-induced phase transition of retained austenite, is responsible for the excellent mechanical properties obtained in the steel. For further investigating the stress-induced phase transition mechanism, thermodynamic methods are applied. Gibbs free energy of face-centered cubic-Fe, ε-Fe, ω-Fe and body-centered cubic-Fe associated with the stress-induced phase transition was calculated using molecular dynamics simulations, and a calculation method of strain energy in thermodynamic units for the stress-induced martensitic transformation is presented. The final results reveal the process and thermodynamic mechanism of stress-induced martensitic transformation in medium-carbon steels, in which the hexagonal phase can participate in the process as an intermediate product. | Mechanisms of strength–plasticity enhancement and stress-induced phase transition in a medium-carbon low-alloy steel | 10.1007/s42243-023-01153-7 |
2024-02-02 | Here, we studied the effect of low-shear modeled microgravity (LSMMG) on cross stress resistance (heat, acid, and oxidative), fatty acid content, and pathogenicity along with alteration in expression of stress-/virulence-associated genes in Legionella pneumophila . The stress resistance analysis result indicated that bacteria cultivated under LSMMG environments showed higher resistance with elevated D -values at 55 °C and in 1 mM of hydrogen peroxide (H 2 O 2 ) conditions compared to normal gravity (NG)-grown bacteria. On the other hand, there was no significant difference in tolerance ( p < 0.05) toward simulated gastric fluid (pH-2.5) acid conditions. In fatty acid analysis, our result showed that a total amount of saturated and cyclic fatty acids was increased in LSMMG-grown cells; as a consequence, they might possess low membrane fluidity. An upregulated expression level was noticed for stress-related genes ( hslV, htrA, grpE, groL, htpG, clpB, clpX, dnaJ, dnaK, rpoH, rpoE, rpoS, kaiB, kaiC, lpp1114, ahpC1, ahpC2, ahpD, grlA, and gst ) under LSMMG conditions. The reduced virulence (less intracellular bacteria and less % of induce apoptosis in RAW 264.7 macrophages) of L. pneumophila under LSMMG conditions may be because of downregulation related genes ( dotA, dotB, dotC, dotD, dotG, dotH, dotL, dotM, dotN, icmK, icmB, icmS, icmT, icmW, ladC, rtxA, letA, rpoN, fleQ, fleR, and fliA ). In the LSMMG group, the expression of inflammation-related factors, such as IL-1α , TNF-α , IL-6 , and IL-8 , was observed to be reduced in infected macrophages. Also, scanning electron microscopy (SEM) analysis showed less number of LSMMG-cultivated bacteria attached to the host macrophages compared to NG. Thus, our study provides understandings about the changes in lipid composition and different genes expression due to LSMMG conditions, which apparently influence the alterations of L. pneumophila ’ stress/virulence response. | Exposure of Legionella pneumophila to low-shear modeled microgravity: impact on stress response, membrane lipid composition, pathogenicity to macrophages and interrelated genes expression | 10.1007/s00203-023-03753-z |
2024-02-01 | Low temperature conditions have been linked to a heightened susceptibility to lower respiratory infections (LRIs). Yet, our comprehension of the LRIs’ disease burden due to such conditions remains limited, especially when considering the diverse socio-demographic indexes (SDIs) and climate types across various nations and regions. We examined the variations over time and space in the impact of LRIs due to low temperatures across a diverse set of 204 nations and regions, each with unique SDIs and climate types, spanning the years 1990 to 2019. Data from the Global Burden of Disease Study 2019 was used for this retrospective analysis. The burden of LRIs attributable to low temperatures was estimated by stratifying by sex, age, country, climate type, and SDI, including age-standardized mortality rate (ASMR) and age-standardized disability-adjusted life year rate (ASDR). We employed Joinpoint models to compute the annual average percent changes (AAPCs) in order to evaluate the trends in LRIs burden due to low temperatures from 1990 to 2019. Furthermore, we utilized Poisson age-period-cohort models to forecast the global and income-specific trends in LRIs burden due to low temperatures for the period 2020–2044. Generalized additive mixed models were used to fit changes in the disease burden of different climate regions. The relationship between SDI and both ASMR and ASDR was determined using models grounded in Gaussian process regression. In general, since the year 1990, there has been a significant reduction in the worldwide impact of LRIs due to low temperatures. This decrease is particularly noticeable among infants and the elderly, as well as in regions with a boreal climate and those with an average SDI. In 2019, LRIs induced by low temperatures showed an ASMR of 2.2 (95% CI: 1.34, 3.07) and an ASDR of 53.73 (95% CI: 17.5, 93.22) for every 100,000 individuals. A global reduction was observed in the ASMR and ASDR for LRIs over the period from 1990 to 2019, showing a decrease of 60.27% and 77.5%, in that order. For ASMR and ASDR, the AAPC values were found to be − 3.3 (95% CI: − 3.4, − 3.1) and − 5 (95% CI: − 5.2, − 4.9), in that order. However, a contrasting pattern was observed in southern Latin America, where an increase was noted in the ASMR for LRIs induced by low temperatures [AAPC: 0.5; 95% CI: (0.3, 0.8)]. Low temperature has decreased as an environmental risk factor for LRIs globally over 30 years, especially in middle SDI regions and boreal climates, but remains important for infants and the elderly population. | Global burden study of lower respiratory infections linked to low temperatures: an analysis from 1990 to 2019 | 10.1007/s11356-023-31587-1 |
2024-02-01 | In this study, the influence of low-temperature plasmas on the surface bonding performance of aluminum (Al) alloys was explored by means of surface treatment. Then, response surface method was employed to optimize the processing technology of low-temperature plasmas, and the interactivities of three factors, namely input power ( p ), spay gun-to-specimen surface distance ( d ) and specimen movement velocity ( v ), with the surface energy of Al alloys were analyzed. The results showed that when p = 800 W, d = 10 mm and v = 2 mm s −1 , the processing technology of low-temperature plasmas was better, and the surface energy reached 75.96 mJ m −2 , which was 147% higher than that before treatment. Moreover, the wettability was evidently improved. After the treatment with low-temperature plasmas, both the varieties and quantity of oxygen-containing functional groups increased, accompanied by enhanced surfactivity of Al alloys. Besides, the tensile shear strength and paint layer adhesion of adhesive bonding Al alloy specimens were apparently elevated by 73.14 and 41.3%, respectively. According to the chemical bonding theory, a key factor contributing to the improved bonding strength of Al alloys lies in the increased varieties and quantity of oxygen-containing functional groups on their surface. | Low-Temperature Plasma Treatment of Aluminum for Improved Surface Bonding | 10.1007/s11665-023-08082-2 |
2024-02-01 | The welding process represents an unintentional, but unavoidable, heat treatment in the form of soft annealing or tempering, but also hardening during the cooling of the melt. Particularly in the case of high-strength fine-grained structural steels, this leads to critical states of the mechanical-technological properties of the base material. In order to investigate the influence of the heat input during welding on the resulting properties of the heat-affected areas, a thermo-physical simulation was carried out on a quenching and forming dilatometer Bähr DIL 805 A/D, considering low-alloyed quenched and tempered (Q&T) and low-alloyed thermo-mechanically controlled processed steels (TMCP) with yield strengths in the range of 500 to 960 MPa (S500MC, S700MC, S770QL, and S960QL). For this purpose, time–temperature cycles based on gas metal arc welding (GMAW) were simulated with different maximum temperatures (1200 °C; 1000 °C; 800 °C), representing the typical microstructural regions of the heat-affected zones (HAZ), and cooling times t 8/5 (5 s; 12 s; 20 s; 25 s) on miniature tensile specimens. To evaluate the property changes of the characteristic HAZ, tensile tests, hardness measurements, and microstructural investigations were analyzed. The investigations illustrate the significant influence of heat input during the welding process on the resulting mechanical-technological properties and microstructure for both kinds of steel. It was demonstrated that all the steels investigated tend to soften with increasing cooling times. The investigated Q&T steels have a lower risk of falling below the strength of the untreated base material than the investigated TMCP fine-grained structural steels. The considerably pronounced softening also resulted in the minimum strength values not being achieved for certain cooling time ranges. | Influence of welding thermal cycles on properties of TMCP and Q&T steels evaluated by thermo-physical simulation | 10.1007/s40194-023-01615-2 |
2024-02-01 | The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester, and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretreatment was discussed by comparing the wear morphology. The results show that liquid nitrogen pretreatment can affect the hardness and interlayer spacing of graphite. The range of the friction coefficients of pretreated graphite changes from 0.17 to 0.22. With the increase of liquid nitrogen pretreatment time, the wear mechanism of graphite would change from dominated three-body wear to adhesion wear. The experimental results of the mechanical seal with liquid nitrogen pretreatment show that the wear rate of stator is less than 0.00165 mm 3 ·N −1 ·m −1 , and the graphite shows a good low-temperature compatibility. | Tribological properties of low-temperature time-dependent pretreated graphite for mechanical seal pairs in high-speed turbopump | 10.1007/s40544-023-0759-1 |
2024-02-01 | Today, arc-based additive manufacturing has great potential for industrial application due to new developments in robotics, welding technology, and computer-aided manufacturing. Two issues are currently the focus of research. One is the accurate generation of geometry with respect to the design, e.g., geometry fidelity, defined roughness, and shape deviations within the tolerances. Here, there are still open questions, particularly with regard to path planning and the dependence of the geometry on the selected process variables. The second topic is the adjustment or determination of the achievable mechanical and microstructural properties, as these are of crucial importance for the use of the technology in industry. The combination of both areas into a geometry- and property-oriented approach to additive manufacturing has been little discussed in the literature for arc-based welding processes. The correlations between cooling conditions and emerging properties can serve as a starting point for such a consideration. The temperature history depends on three key factors: the energy input, the interpass temperature (which in additive manufacturing is determined by the time to over-weld), and the heat transfer conditions, which are determined by the part geometry. The melt pool size or volume also depends on these three constraints. In this study, an approach is presented to realize property-oriented additive manufacturing from the interaction of property-oriented path planning and a melt pool size control system. By controlling the melt pool size, the cooling of the material can be adjusted within certain limits, and consequently, a local adjustment of the microstructure can be achieved, which greatly influences the local mechanical properties. This work demonstrates this approach for a low-alloy filler metal (DIN EN ISO 14341-A G 50 7 M21 4Mo/A5.28 ER80S-D2). Gas metal arc welding was carried out using an M21 shielding gas (82% Ar, 18% CO 2 ). Finally, microstructural characterization will show that different microstructural morphologies and properties can be achieved in a component by combining property-oriented path planning and the use of a control loop to regulate the melt pool size. | Properties oriented WAAM—microstructural and geometrical control in WAAM of low-alloy steel | 10.1007/s40194-023-01666-5 |
2024-02-01 | The world is inundated with millions of tons of industrial wastes such as fly ash, ground granulated blast-furnace slag (GGBS), and mining tailings. The best method to utilize these wastes is to make different types of building materials and include them in structural parts, reducing the carbon footprint. In developing countries such as India, the population explosion raises the need for sustainable construction materials to fulfill the country's excessive consumption. Ambient temperature and elevated temperature-cured fly ash-based geopolymer bricks solve such kind of problems in a less polluting and sustainable manner than other technologies. Nowadays, geopolymerization methods and their applications for making bricks are limited only to laboratory-scale studies, and mass-scale production for making fly ash-based geopolymer bricks has rarely been examined. Therefore, this study is an attempt made by authors to overcome these issues. In the presented study, fly ash/sand-based geopolymer bricks were manufactured incorporating sodium silicate and sodium hydroxide with different molarity of NaOH (8, 12, and 16 M) at an industrial scale and tested for their mechanical properties as well as durability. The fly ash/sand-based geopolymer bricks attained up to 15 MPa compressive strength at 50% fly ash and 50% sand. Optimized samples were tested for durability-related properties, and results exhibit a more durable nature compared to burnt clay bricks and cement-based fly ash bricks. Thus, the development of fly ash-based geopolymer bricks is an energy-efficient and cleaner way to utilize fly ash. Graphical Abstract | Industrial Production of Fly Ash and Sand-Based Geopolymer Bricks Using Different Molarity of NaOH Solution, and Assessment of their Mechanical and Durability Properties | 10.1007/s40996-023-01154-2 |
2024-02-01 | Heavy components of low-alloy high-strength (LAHS) steels are generally formed by multi-pass forging. It is necessary to explore the flow characteristics and hot workability of LAHS steels during the multi-pass forging process, which is beneficial to the formulation of actual processing parameters. In the study, the multi-pass hot compression experiments of a typical LAHS steel are carried out at a wide range of deformation temperatures and strain rates. It is found that the work hardening rate of the experimental material depends on deformation parameters and deformation passes, which is ascribed to the impacts of static and dynamic softening behaviors. A new model is established to describe the flow characteristics at various deformation passes. Compared to the classical Arrhenius model and modified Zerilli and Armstrong model, the newly proposed model shows higher prediction accuracy with a confidence level of 0.98565. Furthermore, the connection between power dissipation efficiency (PDE) and deformation parameters is revealed by analyzing the microstructures. The PDE cannot be utilized to reflect the efficiency of energy dissipation for microstructure evolution during the entire deformation process, but only to assess the efficiency of energy dissipation for microstructure evolution in a specific deformation parameter state. As a result, an integrated processing map is proposed to better study the hot workability of the LAHS steel, which considers the effects of instability factor (IF), PDE, and distribution and size of grains. The optimized processing parameters for the multi-pass deformation process are the deformation parameters of 1223–1318 K and 0.01–0.08 s −1 . Complete dynamic recrystallization occurs within the optimized processing parameters with an average grain size of 18.36–42.3 µm. This study will guide the optimization of the forging process of heavy components. | Flow characteristics and hot workability of a typical low-alloy high-strength steel during multi-pass deformation | 10.1007/s12613-023-2736-0 |
2024-02-01 | Fire is generally aftermath of an earthquake because of damaged gas pipelines, electrical short circuits, etc. This increases the vulnerability for greater damage to structures and human. In order to mitigate the damage, authors designed and developed an earthquake-resistant high strength steel with fire resistance using Thermo-Calc software. The designed micro-alloyed steel was produced in vacuum induction furnace and casted into ingots. Subsequently, the ingots were rolled to the preferred size in 2/4 high rolling mill. From the rolled plates, desired UTM samples were fabricated. The fabricated samples were quenched in different quench media like brine, water and forced air after preheating to 1050 °C in order to obtain TEMPCORE properties (martensite at the outer ring and ferrite plus pearlite at the core) in the final product. Though various quenching media were used, water quenched samples were giving desired results and hence these samples were used for further fire resistance studies. SEM and TEM studies were performed on these samples at various stages. It was observed that pearlite formed at the core and martensite at the outer ring transformed from the ferrite and the same was confirmed by EBSD. From the TEM studies, it was observed that there is formation of tempered martensite laths and nano-sized nodular carbides of V, Nb and Mo resulting in high yield strength of 715 and 477 MPa at room temperature as well as at elevated temperature of 650 °C, respectively. | Development of High Strength Fire-Resistant Earthquake Steel | 10.1007/s11665-023-08110-1 |
2024-02-01 | Temperature-responsive polymers have garnered significant attention due to their ability to respond to external stimuli. In this work, dual temperature-responsive block copolymers are synthesized via reversible addition-fragmentation chain transfer polymerization (RAFT) polymerization utilizing zwitterionic monomer methacryloyl ethyl sulfobetaine (SBMA) and N -isopropyl acrylamide (NIPAAm) as monomers. The thermal responsive behaviors can be easily modulated by incorporating additional hydrophobic monomer benzyl acrylate (BN) or hydrophilic monomer acrylic acid (AA), adjusting concentration or pH, or varying the degree of polymerization of the block chain segments. The cloud points of the copolymers are determined by UV-Vis spectrophotometry, and these copolymers exhibit both controlled upper and lower critical solubility temperatures (LCST and UCST) in aqueous solution. This study analyzes and summarizes the influencing factors of dual temperature responsive block copolymers by exploring the effects of various conditions on the phase transition temperature of temperature-sensitive polymers to explore the relationship between their properties and environment and structure to make them more selective in terms of temperature application range and regulation laws. It is very interesting that the introduction of poly-acrylic acid (PAA) segments in the middle of di-block copolymer PSBMA 55 - b -PNIPAAm 80 to form PSBMA 55 - b -PAA x - b -PNIPAAm 80 results in a reversal of temperature-responsive behaviors from ‘U’ (LCST < UCST) to ‘n’ (LCST > UCST) type, while the copolymer PSBMA 55 - b -P(NIPAAm 80 - co -AA x ) not. This work provides a clue for tuning the phase transition behavior of polymers for manufacture of extreme smart materials. | Manipulating the Phase Transition Behavior of Dual Temperature-Responsive Block Copolymers by Adjusting Composition and Sequence | 10.1007/s10118-023-3041-0 |
2024-02-01 | A large amount of open-dumped electrolytic manganese residue (EMR) has posed a severe threat to the ecosystem and public health due to the leaching of ammonia (NH 4 + ) and manganese (Mn). In this study, CaO addition coupled with low-temperature roasting was applied for the treatment of EMR. The effects of roasting temperature, roasting time, CaO-EMR mass ratio and solid–liquid ratio were investigated. The most cost-effective and practically viable condition was explored through response surface methodology. At a CaO: EMR ratio of 1:16.7, after roasting at 187 °C for 60 min, the leaching concentrations of NH 4 + and Mn dropped to 10.18 mg/L and 1.05 mg/L, respectively, below their discharge standards. In addition, the magnesium hazard (MH) of EMR, which was often neglected, was studied. After treatment, the MH of the EMR leachate was reduced from 60 to 37. Mechanism analysis reveals that roasting can promote NH 4 + to escape as NH 3 and convert dihydrate gypsum to hemihydrate gypsum. Mn 2+ and Mg 2+ were mainly solidified as MnO 2 and Mg(OH) 2 , respectively. This study proposes an efficient and low-cost approach for the treatment of EMR and provides valuable information for its practical application. | Ammonia removal and simultaneous immobilization of manganese and magnesium from electrolytic manganese residue by a low-temperature CaO roasting process | 10.1007/s11356-024-31895-0 |
2024-02-01 | The present study deals with the film condensation of the retrofit refrigerant R32 over a single horizontal plain and four 2D low-finned integral tubes with varying fin densities, viz., 24 FPI, 32 FPI, 40 FPI, and 48 FPI, having trapezoidal fin shapes, at a condensing temperature of 40 ± 0.5 °C and subcooling temperature ranging from 3 to 11 °C. For the plain and complete 2D low-finned integral finned tubes under consideration, the coefficient of condensing-side heat transfer falls with an increase in the sub-cooling temperature. As the fin density increases from 24 to 32 FPI, the condensing-side heat transfer increases by an average increment of 31%, and as the fin density increases further to 40 FPI and then to 48 FPI, the condensation heat transfer decreases by 13.3 and 23.8%, respectively. Among the 2D low-finned integral tubes tested, the 32 FPI fin density showed the best heat transmission performance. Furthermore, following a similar pattern, the coefficients of condensing-side heat transfer for the entire tubes fall as the heat flux rises. In comparison with the plain tube, the entire 2D low-finned integral finned tubes, viz., 24 FPI, 32 FPI, 40 FPI, and 48 FPI, showed higher coefficients of condensation heat transfers with enhancement ratios of 4.4, 5.7, 4.9, and 4.6, respectively. Among the six theoretical models compared, the Honda Nozu model showed the lowest average deviation percentage compared to the experimental values. Nusselt’s model predicted the experimental findings for the plain tube with an average variation of ± 10%. | Experimental Study of the Condensation of Retrofit Refrigerant R32 Over Single Horizontal Plain and 2D Low-Finned Integral Tubes | 10.1007/s13369-023-08080-5 |
2024-02-01 | An effect of Cu-doped Ni-Zn nanoferrite particles synthesized through the citrate gel auto-combustion method on structural dielectric and magnetic properties was investigated. The structural characterization of synthesized powder is investigated using XRD (X-ray diffraction), FE-SEM (field emission scanning electron microscopy), EDXS (energy-dispersive X-ray spectroscopy), AFM (atomic force microscope), and TEM (transmission electron microscope). All prepared samples were established to have a single-phase spinel structure and fine grain size with an Fd-3 m space group. The lattice parameter, volume, and crystallite size decrease with increasing copper substitution. By adding copper ions, the surface area rises from 123.9 to 187.4 m 2 g −1 . The surface roughness is increased by AFM examination from 7.6 to 11 nm. From the AFM samples, it is shown that they are soft to hard in nature due to the Cu doping. The real imaginary impedance and the complex electric modulus were studied within the frequency range of 20 Hz to 1 kHz at room temperature, respectively. In the Cole–Cole plots studied for dielectric constant, it was observed that all samples had single semi-circles and continuously decreased with increasing copper content. This shows that the prepared material is good for high-resistance applications and the fabrication of multilayer inductor chips. The magnetic characteristics of hysteresis loops were studied at room temperature using a VSM (vibration sample magnetometer) for nanoferrites. The prepared ferrites samples were examined; copper doping increased the width of the loops, which confirms the change from soft to hard magnetic material. They are utilized in data processing, telecommunications, and the automobile industries. At low temperatures, the prepared samples showed superparamagnetic behavior. It is used in medical and electrical device applications. | Structural, dielectric, and magnetic properties of Cu-doped Ni-Zn ferrites | 10.1007/s41779-023-00946-z |
2024-02-01 | Heat-assisted development of shale oil and gas is recognized as a vital technique for the efficient extraction of shale gas; however, there is a need for comprehensive investigation regarding radon release during the extraction process. The aim of this study was to investigate the pore structure and radon release characteristics of heat-treated black shale using low-temperature nitrogen adsorption (LTNA) and radon (Rn-222) measurement equipment. The findings reveal that temperature initially enhances radon release, which subsequently decreases. The maximum radon release occurs at 500 °C, reaching 1.46 times the initial stage. The radon release rate is positively correlated with the volume of micropores (< 2 nm) in the shale. Organic pores within the shale serve as the primary storage spaces for radon, and the intricate pore structure of organic matter provides an optimal environment for radon gas retention. These results contribute to elucidating the mechanisms behind the impact of thermal treatment on shale’s radon release rate, which is crucial for guiding radon radiation evaluation in thermal treatment processes. | Study of the influence of pore structure on the radon emission characteristics of terrestrial sedimentary shales after high temperature action | 10.1007/s11356-024-31947-5 |
2024-02-01 | The cabin air pressure remains lower than the horizontal atmospheric pressure when the airplane is in flight. Air pressure is one of the parameters that must be taken into consideration while studying the thermal environment of an airplane cabin. There are still no reference values for aircraft cabins despite the fact that numerous studies on low pressure heat transfer have demonstrated the connection between convective heat transfer coefficient (CHTC) and air pressure. In this paper, a correction method for CHTC under low pressure conditions was established by using the dummy heat dissipation in the low-pressure cabin experiment. On this basis, a thermal environment simulation model was developed, then was applied to the simulation of a seven-row aircraft cabin containing 42 passengers, and the CHTC and heat loss of dummy surface in the cabin were obtained. Finally, the results of PMV calculated by using heat dissipation and air parameters at sampling points were compared. The results show that the modified CHTC can accurately reflect the cabin thermal environment under low pressure conditions, and the correction of CHTC can be realized by adjusting the turbulent Prandtl number, which is nonlinear correlated with the pressure. The simulation results of the thermal environment in the seven-row cabin show that the CHTC changes by about 42% before and after modification. The air pressure decreases during take-off, which reduces the average CHTC of the crew surface from 5.09 W/(m 2 ·K) to 4.56 W/(m 2 ·K), but the air temperature rises by about 0.2 °C as a whole. The deviation of PMV results calculated by using simulated heat loss data and using air parameters of measuring points in space is up to 0.5, but the latter is representative for calculating the thermal comfort level of the whole cabin. | Numerical study of the influence of the atmospheric pressure on the thermal environment in the passenger cabin | 10.1007/s12273-023-1064-7 |
2024-02-01 | The objective of this study was to investigate the influence of strengthening mechanisms on the high-temperature mechanical properties of China low-activation ferrite (CLF-1) steel, which underwent thermodynamic design and thermo-mechanical treatment (TMT). The microstructure characterization in the normalized and tempered condition and the TMT condition was carried out using optical microscopy, X-ray diffractometer, and scanning electron microscopy with electron backscatter diffraction. High-resolution transmission electron microscopy was employed to determine the crystallographic structures of precipitated phases. The results indicated that the addition of Ti led to an increase in the allocation of C in M C phase and an enhancement in the content of M C phase. Compared to CLF-P steel in the normalized and tempered condition, a 1.5-fold increase in dislocation density and an order of magnitude improvement in MX phase density were achieved after TMT. The formation of high-density nano-scale M C phases during TMT played a significant role in precipitation strengthening due to their favorable coherent relationship with the matrix and low interfacial free energy. The excellent high-temperature mechanical properties observed in CLF-P steel after TMT can be attributed to the combined effects of precipitation strengthening, dislocation strengthening, and lath strengthening. | Investigation on Strengthening Mechanism of China Low-Activation Ferrite Steel upon Thermo-Mechanical Treatment | 10.1007/s40195-023-01629-1 |
2024-02-01 | This study describes the effects of incorporating insoluble soy fiber and low acyl gellan gum as an alternative for wheat gluten in plant-based meat analogs made from soy protein isolate (SPI). The formulations containing insoluble soy fiber (ranging from 0 to 3%) and low acyl gellan gum (0–2%) were processed in a high-temperature shear cell (HTSC) and then analyzed in terms of macrostructure, microstructure, rheological properties, tensile strength, and water absorption capacity (WAC). Macrostructural analysis revealed that the control product containing SPI without insoluble soy fiber and low acyl gellan gum exhibited a dense and gel-like structure, devoid of visible fibers. The addition of 1, 2, and 3 wt.% of insoluble soy fiber increased the formation of visually elongated fibers in both macro- and microscopic levels in the shear direction, resulting in anisotropic plant-based meat analogs with improved tensile strength and elasticity. The use of 1 and 2 wt.% low acyl gellan gum led to the formation of short and thin filaments that were less oriented in the shear direction, resulting in decreased tensile strength. When combined with low acyl gellan gum, insoluble soy fiber failed to produce lengthy and elongated fibers, resulting in short and thin fibrils. These findings suggest that the interaction between insoluble soy fiber and low acyl gellan gum under the processing conditions may hinder fiber formation and mechanical anisotropy. Microscopic examination reveals smoother regions in products enriched with insoluble soy fiber and rougher surfaces in those containing low acyl gellan gum. Moreover, X-ray microtomography confirms that insoluble soy fiber enhanced air retention, contributing to enhanced structural integrity. In contrast, low acyl gellan gum introduces irregularly shaped air bubbles, compromising structural improvement. In summary, this study underscores the potential of insoluble soy fiber to enhance the structural and the textural properties of plant-based meat analogs. However, it also highlights the challenges posed by low acyl gellan gum, which, despite improving water retention, may hinder fiber formation and mechanical anisotropy. These findings offer insights for advancing the quality of plant-based meat products. | Improving the quality of gluten-free plant-based meat analogs based on soy protein isolate with insoluble soy fibers and low acyl gellan gum | 10.1007/s00217-023-04391-x |
2024-02-01 | In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium (LVTC), the oxidation behavior of LVTC was investigated. The results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700 °C, and the main phases of the oxidized LVTC consisted of Fe 9 TiO 15 , Fe 2 O 3 , CaSiTiO 5 and a small amount of Fe 2.75 Ti 0.25 O 4 . Increasing temperature is favorable to the formation of Fe 2 TiO 5 . The surface of LVTC gradually becomes rough, with fine particles of needle-like and granular shape appearing on the surface, which finally turn from laminar to creamy, spread out, and are interspersed with many tiny holes. The phase oxidation paths in LVTC were as follows: (1) Fe 2.75 Ti 0.25 O 4 → Fe 9 TiO 15 + Fe 2 O 3 ; (2) Fe 2.75 Ti 0.25 O 4 → Fe 2 O 3 + FeTiO 3 → Fe 2 TiO 5 ; (3) FeTiO 3 → Fe 2 O 3 + Fe 2 Ti 3 O 9 → Fe 2 TiO 5 . LVTC is predominantly mesoporous whether oxidized or not, with the pores mainly distributed in the range of 2–40 nm, and the specific surface area of LVTC decreases significantly with increasing temperature. | Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium | 10.1007/s42243-023-01077-2 |
2024-02-01 | Cold stress (CS) impact on crops is one of the critical constraints for sustainable and smart agricultural production. CS adversely affects plants leading to growth retardation, necrosis, chlorosis, and significant yield loss. The objective of this study was to explore the mechanistic basis of silicon (Si) in enhancing CS tolerance in alfalfa plants. The fluorescence staining indicated that Si-reduced the intensity of CS-induced superoxide radical (O 2 •– ) and hydrogen peroxide (H 2 O 2 ) generation in plants that improved plant photosynthesis, cellular integrity, and alfalfa biomass production under CS. The exogenous supplementation of Si significantly restored the endogenous Si status accompanied by the upregulation of NIP (nodulin 26-like intrinsic protein) genes NIP2 , NIP5;1 , and NIP6;1 in alfalfa. The elemental concentration analysis revealed that exogenous silicon (E-Si) triggers the increase of calcium (Ca), magnesium (Mg), and sulfur (S) in plants subjected to Si-supplementation compared to the plants cultivated without Si under CS. The application of Si significantly increased the activity of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR). Furthermore, Si significantly enhanced the expression of CS-responsive candidate genes including ICE1 , CBF1/DREB1C , CBF2/DREB1B , CBF3/DREB1A , COR15A , COR47 , and KIN1 in alfalfa. These findings together provide mechanistic insights into Si-involving CS tolerance in alfalfa. This eco-friendly SC management strategy using Si treatment can be useful to plant breeders and farmers for developing CS-resilient smart alfalfa production through breeding program. | Mechanistic Basis of Silicon Mediated Cold Stress Tolerance in Alfalfa (Medicago sativa L.) | 10.1007/s12633-023-02697-9 |
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