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2023-08-14 | In this study, the microstructural evolution of Ag films with different amounts of (111)-oriented grains and coincident site lattice Σ3 (CSL-Σ3) twin boundaries after low-temperature direct bonding was demonstrated. The highly (111)-oriented surface grains provided the rapid surface diffusion paths and the special twin boundaries contributed to structural stability of the Ag films during bonding. Combining both, perfect bonding can be achieved at a low temperature of 150 °C for 60 min in the bonding of Ag films with 99.4% (111) grains. Owing to the low recrystallization temperature, bonding interfaces with only a few small voids were observed after bonding at 250 °C for 30 min. Annealing twins grew across the bonding interface and extended to the other side of the Ag films, implying a strong bonding strength. Though increasing the bonding temperature and period could help to achieve a bonding interface with the least voids formed, it was suggested that increasing the amount of (111) grains on the Ag film bonding surfaces is the key point to achieved perfect bonding at temperatures lower than 250 °C. This would provide great potential for Ag as a suitable material for applications in three-dimensional integrated circuit (3D-IC) interconnections. | Low Temperature Diffusion Bonding of Si Chips Sputtered with High Density (111)-Ag Nanotwinned Films | 10.1007/s11665-023-08534-9 |
2023-08-14 | The Pacific white shrimp ( Litopenaeus vannamei ) is an economically important aquaculture species worldwide. Antioxidant immune performance is an important indicator of healthy growth and physiology of aquatic organisms. In this study, we compared the antioxidant capacity and immune response between a low salt tolerant hybrid and a normal variety of shrimp (control) cultured at different salinities (1‰, 5‰, and 15‰). At 1‰ salinity, the apoptotic cell numbers, apoptosis rate, and reactive oxygen content of the hybrid group were significantly lower than those of the control group. The hybrid group also had stronger antioxidant enzyme activities (glutathione peroxidase, glutathione transferase, superoxide dismutase, catalase) and higher gene expression levels. In addition, the hybrid group cultured at low salinity (1‰ and 5‰) had significantly higher total hemocyte count, phagocytic rate, and respiratory burst than the control group. Similarly, the hybrid group had higher immune-related enzyme (acid phosphatase, alkaline phosphatase, lysozyme, phenol oxidase) activities and gene expression levels than the control group at low salinity. These results show that the hybrid population had better antioxidant and immune capacity than the normal variety when cultured under low salinity conditions, and they lay the foundation for selection and breeding of low-salt tolerant, high-quality Pacific white shrimp. | Comparison of antioxidant capacity and immune response between low salinity tolerant hybrid and normal variety of Pacific white shrimp (Litopenaeus vannamei) | 10.1007/s10499-023-01248-8 |
2023-08-13 | Background The aryl hydrocarbon receptor (AhR) is a transcription factor that plays a crucial role in regulating the immune system and maintaining skin barrier function. AhR signaling is pivotal in the pathogenesis of inflammatory diseases such as atopic dermatitis (AD), and the absence of AhR ligands further contributes to the progression or worsening of AD symptoms. Methods AD was induced with 2,4-dinitrochlorobenzene (DNCB), and Bojungikgi-tang (BJIKT) was administered orally daily for 10 weeks. Serum IgE, splenocyte IL-4, and IFN-γ levels, skin barrier genes, and AhR target gene expressions were analyzed using RNA-sequencing analysis. Spleen tissues were extracted for fluorescence-activated cell sorting (FACS) analysis to analyze the effect of BJIKT on immune responses. A correlation analysis was conducted to analyze the correlation between immune markers and skin barrier genes and AhR target genes. Results BJIKT effectively improved AD symptoms in AD mice fed a low AhR ligand diet by reducing neutrophil and eosinophil counts, lowering IgE levels in the blood, and decreasing IL-4 and IFN-γ levels in the splenocytes. Additionally, BJIKT significantly reduced epithelial skin thickness and transepidermal water loss (TEWL) values and reversed the decreased expression of skin barrier genes. BJIKT also considerably altered the expression of AhR target genes, including Ahr, Ahrr, cytochrome P450 1A1 (CYP1A1), and CYP1B1. Furthermore, AhR target pathway genes were negatively correlated with immune cell subtypes, including CD4 + and CD8 + T cells and macrophages (CD11b + F4/80 +) at the systemic level. Conclusions BJIKT can regulate AhR activation and may help reduce inflammation in AD by regulating the expression of skin barrier genes and immune responses. | Bojungikgi-tang improves skin barrier function and immune response in atopic dermatitis mice fed a low aryl hydrocarbon receptor ligand diet | 10.1186/s13020-023-00806-9 |
2023-08-12 | Introduction Sickle cell disease (SCD) in pregnancy is associated with worse maternal and neonatal outcomes. There is limited available data describing the burden and outcomes of critically ill obstetric patients affected by SCD in low-income settings. Objectives We aimed to define SCD burden and impact on mortality in critically-ill obstetric patients admitted to an urban referral hospital in Sierra Leone. We hypothesized that SCD burden is high and independently associated with increased mortality. Methods We performed a registry-based cross-sectional study from March 2020 to December 2021 in the high-dependency unit (HDU) of Princess Christian Maternity Hospital PCMH, Freetown. Primary endpoints were the proportion of patients identified in the SCD group and HDU mortality. Secondary endpoints included frequency of maternal direct obstetric complications (MDOCs) and the maternal early obstetric warning score (MEOWS). Results Out of a total of 497 patients, 25 (5.5%) qualified to be included in the SCD group. MEOWS on admission was not different between patients with and without SCD and SCD patients had also less frequently reported MDOCs. Yet, crude HDU mortality in the SCD group was 36%, compared to 9.5% in the non SCD group ( P < 0.01), with an independent association between SCD group exposure and mortality when accounting for severity on admission (hazard ratio 3.40; 95%CI 1.57—7.39; P = 0.002). Patients with SCD had a tendency to longer HDU length of stay. Conclusions One out of twenty patients accessing a HDU in Sierra Leone fulfilled criteria for SCD. Despite comparable severity on admission, mortality in SCD patients was four times higher than patients without SCD. Optimization of intermediate and intensive care for this group of patients should be prioritized in low-resource settings with high maternal mortality. | Impact and burden of sickle cell disease in critically ill obstetric patients in a high dependency unit in Sierra Leone—a registry based evaluation | 10.1186/s12884-023-05888-9 |
2023-08-11 | The MXene-boosted rapid gelling expedites the assembly of flexible thermocell arrays, overcoming the typical constraint of complicated device fabrication processes. The hydrogel electrolyte can sustain stable thermoelectrochemical performance under various challenging conditions, including large, repeated, and sustained deformations, and multiple cut-healing cycles. The as-assembled thermocell array exhibits device-level self-healing capability and high adaptability to human body, efficiently harvesting low-grade heat for wearable applications. The evolution of wearable technology has prompted the need for adaptive, self-healable, and energy-autonomous energy devices. This study innovatively addresses this challenge by introducing an MXene-boosted hydrogel electrolyte, which expedites the assembly process of flexible thermocell (TEC) arrays and thus circumvents the complicated fabrication of typical wearable electronics. Our findings underscore the hydrogel electrolyte's superior thermoelectrochemical performance under substantial deformations and repeated self-healing cycles. The resulting hydrogel-based TEC yields a maximum power output of 1032.1 nW under the Δ T of 20 K when being stretched to 500% for 1000 cycles, corresponding to 80% of its initial state; meanwhile, it sustains 1179.1 nW under the Δ T of 20 K even after 60 cut-healing cycles, approximately 92% of its initial state. The as-assembled TEC array exhibits device-level self-healing capability and high adaptability to human body. It is readily applied for touch-based encrypted communication where distinct voltage signals can be converted into alphabet letters; it is also employed as a self-powered sensor to in-situ monitor a variety of body motions for complex human actions. The swift assembly approach, combined with the versatile functionality of the TEC device, paves the way for future advancements in wearable electronics targeting at fitness monitoring and human–machine interfaces. | Swift Assembly of Adaptive Thermocell Arrays for Device-Level Healable and Energy-Autonomous Motion Sensors | 10.1007/s40820-023-01170-x |
2023-08-11 | We consider the Laplace operator on a triangle, subject to attractive Robin boundary conditions. We prove that the equilateral triangle is a local maximiser of the lowest eigenvalue among all triangles of a given area provided that the negative boundary parameter is sufficiently small in absolute value, with the smallness depending on the area only. Moreover, using various trial functions, we obtain sufficient conditions for the global optimality of the equilateral triangle under fixed area constraint in the regimes of small and large couplings. We also discuss the constraint of fixed perimeter. | Reverse Isoperimetric Inequality for the Lowest Robin Eigenvalue of a Triangle | 10.1007/s00245-023-10033-1 |
2023-08-10 | Abstract Waxy crude oil transported with a polymeric pour point depressant (PPD) is an effective technology to improve the economics and safety of pipeline transport. According to recent studies, nanoparticles grafted with traditional PPD molecules perform better than pure traditional polymers. Nanocomposites could act as the center of a heterogeneous wax chain nucleation, featuring the property of dispersing wax crystal particles and making wax crystals more compact thus improving the low-temperature fluidity of waxy crude oil. This paper summarizes the recent work on PPDs using various kinds of polymers and nanomaterials for the preparation of nanocomposites over the last few years, with a focus on reviewing the mechanism of action of different types of nanomaterials. Finally, future challenges ahead for nanocomposite PPD research are stated. | A Mini-Review of Nanocomposite Pour Point Depressants | 10.1134/S0965544123050031 |
2023-08-10 | In this paper, the microstructure and mechanical properties of a new type of low Ni duplex stainless steel after resistance spot welding were studied. The welding current has a great influence on the welding performance of resistance spot welding, so it is necessary to clarify the influence law and mechanism of welding current on the welding performance of low Ni duplex stainless steel. The microstructure of the samples under different welding currents was analyzed in detail by EBSD, and the mechanical properties of the treated samples were measured. The results show that the volume fraction of austenite in nugget zone is affected by changing welding current. This is because the higher cooling rate of resistance spot welding inhibits the phase transformation of ferrite to austenite and reduces the volume fraction of austenite, resulting in the imbalance of ferrite and austenite phases. When the welding current is the largest, the cooling rate is the lowest, which corresponds to the highest austenite volume fraction. | Study on Microstructure and Mechanical Properties of a New Type of Low Ni Duplex Stainless Steel Resistance Spot Welding | 10.1007/s11665-023-08595-w |
2023-08-09 | The study presents multi-peak vertical structure of westward propagating quasi-two-day wave with wave-number 3 (W3) and its formation mechanisms in the mesosphere–lower thermosphere, using two decades of multi-satellite measurements, for the first time. W3 in austral summer shows a multi peak vertical structure, with two prominent peaks having amplitudes of 11.24 ± 2.2 K and 8.66 ± 1.1 K at 108 km (M1) and 84 km (M2), respectively. Genesis of this multi-peak structure, which is not explored in details hitherto, is investigated. While weak eastward/westward winds favour vertical growth of W3 in the regions of M1 and M2, strong eastward winds weaken W3 in the region between M1 and M2. These changes in zonal winds are modulated by the altitude variations in meridional temperature gradient and gravity wave filtering. Thus, vertically alternating changes in wind and meridional temperature gradient are the potential drivers for the multi-peak vertical structure of W3, which will be of importance for atmosphere–ionosphere coupling processes. Graphical Abstract | On the genesis of multi-peak vertical structure of quasi-two-day waves in the mesosphere–lower thermosphere | 10.1186/s40623-023-01875-8 |
2023-08-07 | The main objective of this in vivo study was to investigate the effect of different low-level laser therapy (LLLT) doses on polycystic ovary syndrome (PCOS). In the present experimental study, a single dosage of estradiol valerate (EV) was administered to induce PCOS in female rats. After administration of the EV for induction of PCOS, rats were divided into 5 groups ( n = 8/group): C group (animals that were not exposed to any form of procedure), PC group (no treatment following EV induction), L 1 group (1 J/cm 2 LLLT treatment following EV induction), L 2 group (2 J/cm 2 LLLT treatment following EV induction), L 3 group (6 J/cm 2 LLLT treatment following EV induction). The results indicated that no significant difference was found in the serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and progesterone (P4) between the C and L 2 groups ( p < 0.05). Although the serum levels of testosterone (T) were significantly higher in the C group compared with other groups ( p < 0.05), the L 2 group was determined to be the closest to the C group. Additionally, the LH, FSH, and T receptor level of the L 2 group was closest to the C group. In conclusion, a 2 J/cm 2 dosage of LLLT (L 2 group) can be considered the most potentially effective treatment of PCOS in the rat. However, more studies are needed to determine the optimal dose of LLLT for the treatment of PCOS. | The effects of low-level laser therapy on polycystic ovarian syndrome in rats: three different dosages | 10.1007/s10103-023-03847-6 |
2023-08-04 | Low-temperature cracking is a prominent disease form of asphalt pavement, and the formation of early cracks mainly occurs at the interface of the mixture. In order to gain a deeper understanding of the microscopic interfacial behavior of asphalt mixtures cracking at low temperatures, an asphalt–aggregate interface model and an asphalt–asphalt interface model were developed through molecular dynamics simulations. Tensile simulations were carried out at six different temperatures of 0 °C, − 10 °C, − 20 °C, − 30 °C, −40 °C and − 50 °C. Using the interfacial stress as an evaluation index, the change in interfacial strength under different low-temperature conditions was investigated and compared with the macroscopic test results. The results show that the molecular dynamics (MD) simulations are in high agreement with the macroscopic tests. The interaction and damage behavior of the asphalt–asphalt interface are more complex than that of the asphalt–aggregate interface. The interfacial strength of the two models decreases with the decrease of temperature. The temperature sensitivity of the asphalt–asphalt model is higher. In the range of 0 °C to − 50 °C, adhesion failure between asphalt and aggregate predominates, while after − 50 °C, cohesive failure between asphalt is more likely to occur. The macroscopic test results show that the gradation, void ratio and asphalt content have significant effects on the low-temperature cracking resistance of the mixture. | Micro-structural Behavior and Macro-experimental Analysis of Asphalt Mixture Cracking at Low Temperature Based on Molecular Simulation | 10.1007/s42947-023-00362-3 |
2023-08-04 | This paper gives an overview of various factors that influences the performance of Limestone Calcined Clay Cement (LC3) concrete. Among the various research related to ternary cements, this paper discusses the influential factors, based on the strength and durability aspects. The factors such as the type and purity of kaolinite, limestone, gradation of the limestone, concentration of gypsum, calcined clay, limestone ratio, clinker content, water-to-binder ratio, method and effect of calcination, grinding criteria, optimum temperature of calcination, calcined clay content, method of curing and other factors are interpreted. Even low-grade materials with minimum purity have also been found to achieve the desired properties. Therefore depending upon the knowledge of the importance of every parameter, the best quality concrete could be developed with the available source and facilities. With the available quality and quantity of material, sustainable ternary cement could be obtained. By optimizing the various factors that influence the behavior of LC3 concretes, more economical and durable concrete can be produced. Graphical abstract | A review on the factors influencing the performance of sustainable ternary cement composites | 10.1007/s10668-023-03685-0 |
2023-08-04 | Rare earth Gd 3+ -substituted BiFeO 3 nanoparticles’ chemical formula is Bi 1-x Gd x FeO 3 (BGF) (0, 0.01, 0.03, 0.05, 0.07, 0.1) multiferroic created using the citrate gel auto-combustion technique. The structural change from rhombohedral to orthorhombic is confirmed by X-ray diffraction (XRD) studies, and a decrease in average particle size with an increase in Gd concentration has been observed. Morphology and elemental parentage in the sample were studied with a scanning electron microscope (SEM) and energy-dispersive X-ray (EDAX) analysis. The FTIR spectroscopy measurement confirms the chemical bonds present in the sample. UV absorption spectroscopy showed a decrease in the optical band gap with doping concentration. Improved ferroelectric properties were observed with the polarization–electric field (P-E). With an increasing doping concentration, the saturation polarization ( P max ) and remanent polarization (Pr) increase. Low temperature and room temperature magnetic properties were studied to understand the magnetic Gd doping in BiFeO 3 . Generally, they are used in industrial applications like transformer cores, magnetic sensors, and chips. | Rare Earth Gd3+-Substituted BiFeO3 Perovskite Nanoparticles: Synthesis, Structural, Optical, and Magnetic Properties | 10.1007/s13538-023-01349-y |
2023-08-04 | Long-term storage of apples ( Malus x domestica , Borkh.) is increasingly taking place under Dynamic Controlled Atmosphere (DCA). The oxygen level is lowered to ≤ 1 kPa O 2 and the apples are stored just above the Lower Oxygen Limit (LOL). Low oxygen stress during controlled atmosphere storage can lead to fermentation in apples if oxygen levels are too low. Chlorophyll fluorescence can be used to detect low-oxygen stress at an early stage during storage. The currently available non-imaging fluorescence systems often use the minimal fluorescence ( Fo ) parameter. In contrast, the use of chlorophyll fluorescence kinetics is insufficiently described. Therefore, this study aimed to gain more knowledge about the response of chlorophyll fluorescence kinetics to low oxygen stress in apples using a fluorescence imaging system. The results show that the kinetic fluorescence curves differ under aerobic and fermentation conditions. The fermentative conditions initiated a decrease in fluorescence intensity upon application of the saturation pulses during exposure to actinic light. This result was made at 18 °C and 2 °C ambient temperatures. Interestingly, the kinetic curve changed at 2 °C before fermentation products accumulated in the apples. Non-photochemical quenching ( NPQ ) decreased under fermentation conditions in the dark phase after relaxation. Upon entering the dark relaxation phase after Kautsky induction, ɸPSII began to increase. Under atmospheric oxygen conditions, ɸPSII reached values of 0.81 to 0.76, while under fermentation, ɸPSII values ranged from 0.57 to 0.44. | Recording of Low-Oxygen Stress Response Using Chlorophyll Fluorescence Kinetics in Apple Fruit | 10.1007/s11947-023-03183-1 |
2023-08-03 | Traffic-related air pollutants are especially prevalent in border cities with multiple ports of entry (POEs). Excessive emissions due to long delays of idling commercial and passenger vehicles at the POEs could exacerbate various types of respiratory health conditions for the POE users and workers. We conducted a 1-month in-traffic air monitoring campaign at a POE in El Paso, Texas using three continuous FEM instruments for three criteria pollutants (PM, O 3 , and NO 2 ). Concurrent monitoring of PM in the nearby community was performed using a number of low-cost PM sensors. The 1-month average PM 2.5 concentration at the POE was found below 11.6 µg/m 3 , while the 5-min average of in-traffic PM 2.5 concentration could be as high as 450 µg/m 3 . The in-traffic PM 2.5 concentrations were comparable to the data concurrently measured in a state-operated community monitoring site approximately 0.4 km away from the POE. Ozone (O 3 ) concentrations remained low in the region. The in-traffic 1-h NO 2 concentrations were below the 1-h NAAQS of 100 ppb, except for only two 5-min intervals. Our results suggest that traffic emissions do not result in elevated levels of pollutant concentrations at this POE compared to the concentration levels observed in the nearby community. In addition, the performance and accuracy of the low-cost sensors appear to be less reliable during our study, although the devices were capable of detecting the trends and variability in pollutant concentrations in real time. | Measurements of traffic-related air pollution at a U.S.–Mexico port of entry and its impacts on nearby community | 10.1007/s44274-023-00010-4 |
2023-08-03 | In an abandoned sand pit near Ballendorf (Alb-Donau District, Baden-Württemberg), sediments of the Upper Marine Molasse (Lower Miocene) are present. In these sediments, 39 shark and ray species belonging to 29 genera were identified ( Aetobatus, Alopias, Araloselachus, Carcharhinus, Carcharias , Centrophorus, Chaenogaleus, Dasyatis, Galeocerdo, Hemipristis, Iago, Isistius, Keasius, Notorynchus, Pachyscyllium, Paragaleus, Physogaleus, Pristiophorus, Raja, Rhinobatos, Rhinoptera, Rhizoprionodon, Rhynchobatus, Scyliorhinus, Sphyrna, Squalus, Squatina , Taeniurops, Triakis ). However, in this paper we only illustrate and describe the 23 taxa not already discussed in previous publications on the Upper Marine Molasse deposits of Äpfingen, Rengetsweiler and Ursendorf, apart from two exceptions: teeth from jaw positions not previously illustrated, and specimens that are better preserved than those in previous publications. Specimens only determined as “sp.” were illustrated because it cannot be ruled out that they represent different species to the ones published earlier. Nearly all of the taxa found have Recent relatives; only Araloselachus, Keasius and Physogaleus are extinct. Most of the recovered taxa lived on or near the bottom in the shelf region. Alopias and possibly also Keasius lived higher in the water column. With Isistius , a taxon living in the oceanic realm was present, and the Recent representatives of Centrophorus live in deeper waters. Nearly all taxa fed on invertebrates and/or fishes; Isistius also fed as an ectoparasite. Additionally, two generalist feeders ( Galeocerdo , Notorynchus ) and one filter feeder ( Keasius ) were identified. The species Carcharias crassidens , which is not common in the Upper Marine Molasse, was also verified. Other fossils found in this deposit include remnants of odontocete cetaceans, molluscs, balanid barnacles, algae, and teeth of terrestrial mammals. The palaeoenvironment was a warm, shallow-water habitat. Based on greater proximity to the palaeo-coastline, the water depth was probably less than in other Upper Marine Molasse deposits. | The shark and ray teeth of the Lower Miocene (Upper Marine Molasse) from Ballendorf, Baden-Württemberg, Southern Germany | 10.1007/s12549-023-00582-2 |
2023-08-02 | Low-grade heat recovery has received increasing attention as an essential contributor to improving overall energy utilization efficiency and facilitating the carbon neutrality commitment. Here, we developed a techno-economic analysis model of converting low-grade heat into electricity and hydrogen via the osmotic heat engine (OHE) and power-to-gas facility to alleviate the dilemma of lacking practical application scenarios of waste heat. The contribution margin is optimized in real time by either sending the electricity generated by the OHE into the electrolyzer for hydrogen production or selling it at market price in Wuhan, China, thus to identify the economically viable OHE costs under different conditions. Results show that the allowed heat engine cost is significantly impacted by the capacity factor, lifetime and discount rate. The effect of the capacity size of power-to-gas facility on allowed heat engine cost strongly depends on the hydrogen price. The allowed OHE cost increases with the elevating waste heat temperature for each heat transfer scenario. The hybrid energy system can be economically competitive compared with current mature technologies when the waste heat temperature is higher than 68 ℃ and 105 ℃ for fluid and air as heat transfer fluid, respectively. The economically viable heat engine cost is expected to gradually decline from 50,043 ¥/kW to 18,741 ¥/kW within next 15 years. Incentive policy would boost the economic viability of converting low-grade heat into electricity and hydrogen. | Techno-economic analysis of converting low-grade heat into electricity and hydrogen | 10.1007/s43979-023-00059-3 |
2023-08-01 | For decades, the steel production industry has been one of the largest sources of CO 2 emissions, accounting for 7% of global CO 2 emissions, of which 70% is emitted in the iron-making process. Currently, the main low-carbon iron production route is hydrogen metallurgy, which uses renewable energy to generate electricity, electrolyze water to produce hydrogen, and reduce iron with hydrogen. Thus, hydrogen metallurgy is also electrometallurgy. In this context, using the green electric energy one-step electrowinning of iron (ERI) will achieve technical route superiority. Developments in new energy generation technologies have led to renewed interest in ERI because of its green and low-carbon properties. In this study, progress in research into ERI was reviewed, and ERI categories, including molten salts, alkaline aqueous solutions, acidic aqueous solutions, and ionic liquids systems, were discussed. On this basis, ERI methods for various systems, including molten oxide electrolysis (MOE), Cambridge process (FFC), electrowinning, and ionic liquids-based methods, were introduced. Finally, the main challenges and possible solutions were summarized, and the development prospects and opportunities were prospected. The present research work will be beneficial to the development of this field. Graphical abstract | Research progress in the preparation of iron by electrochemical reduction route without CO2 emissions | 10.1007/s10800-023-01870-7 |
2023-08-01 | Presently, selective catalytic reduction (SCR), with either carbon monoxide, urea, hydrocarbons, hydrogen, or ammonia as a reductant, has become a nitrogen oxide (NO x ) removal technology (NO x conversion) of many catalytic companies and diesel engine exhaust gas. Although, there exists a serious threat of low-temperature limitations. So far, certain scientists have shown that barium-based (Ba-based) catalysts have the potential to be highly effective at SCR of NO x at low temperatures when ammonia is used as the reducing agent. The process of NO x storage and reduction which alternate SCR is known as the Lean NO x trap. Herein, we give the condensed advancements and production of the catalysts that involve BaO in low-temperature NH 3 -SCR of NO x , the advantages of BaO catalysts compared to the recently hot electrocatalysis, the stability of BaO catalyst materials, and the condensed advancements and production of the catalysts that involve BaO in low-temperature NH 3 -SCR of NO x . These catalysts are viewed in the light of their preparation method, particulate, and posture in mixed oxides. Also, the characteristic features of Ba-based catalysts are carefully considered and briefed under the following areas: preparation method and precursor, crystallinity, calcination temperature, morphology, acid sites, the specific surface area for reaction, redox property, and activation energy of catalysts. More to these are the discussions on Eley–Rideal [E-R] and Langmuir–Hinshelwood [L–H] mechanisms, the H 2 O/SO 2 and O 2 permissiveness, and the NH 3 -SCR reaction mechanism over Ba-based catalysts highlighting their possible effects. Finally, we proposed the prospect and the likely future research plan for the low-temperature NH 3 -SCR of NO x . | Advancements in low-temperature NH3-SCR of NOx using Ba-based catalysts: a critical review of preparation, mechanisms, and challenges | 10.1007/s11356-023-27703-w |
2023-08-01 | Hot stamping steels have become a crucial strategy for achieving lightweighting and enhancing crash safety in the automotive industry over the past two decades. However, the carbon emissions of the materials and their related stamping processes have been frequently overlooked. It is essential to consider these emissions during the design stage. Emerging materials and technologies in hot stamping pose challenges to the automotive industry's future development in carbon emission reduction. This review discusses the promising materials for future application and their special features, as well as the emerging manufacturing and part design processes that have extended the limit of application for new materials. Advanced heating processes and corresponding equipment have been proven to improve heating efficiency and control temperature uniformity. The material utilization and the overall performance of the components are improved by tailored blanks and an integrated part design approach. To achieve low-carbon-emission (LCE) hot stamping, it is necessary to systematically consider the steel grade, heating process, and part design, rather than solely focusing on reducing carbon emissions during the manufacturing process stage. This review aims to present the latest progress in steel grade, heating process, and part design of hot stamping in the automotive industry, providing solutions for LCE from a holistic perspective. | Low-Carbon-Emission Hot Stamping: A Review from the Perspectives of Steel Grade, Heating Process, and Part Design | 10.1007/s42154-023-00242-3 |
2023-08-01 | In the present analysis, low-velocity impact investigation of a hybrid CNT-fibernano composite twisted conical shell is carried out under varying moisture and thermal environment using finite element methodology. The impact is caused by a spherical impactor at the centre of the panel. The twisted conical shell made of CNT-fibernano composite with cantilever boundary condition can be idealized as turbo machinery blade. The first order shear deformation theory (FSDT) is used to compute the strains and an eight noded isoparametric shell element, which comprises of 5 degree of freedom per node, is used to discretize the panel. The modified Hertzian contact law is used to measure the contact force due the impact between the impactor and the panel. Using Lagrange’s equation of motion, dynamic equation is formulated, considering cantilever boundary condition. The solution of the dynamic equation is obtained by Newmark’s time integration algorithm. The finite element programme is developed and validated with the existing literature to analyse the effect of weight fraction of CNTs, twist angle of the conical shell and the effect of velocity of impact on the contact force, impactor displacement, initial velocity of impactor and indentation. Numerical results reveal that by increasing the weight fraction of CNT, increases the stiffness of the panel thereby the contact forces. However, by increasing the temperature and moisture, the contact force decreases as a result of decrease in stiffness of the structure. The twist angle has striking effects in the contact force histories. | Low-Velocity Impact Response of Hybrid CNTs Reinforced Conical Shell Under Hygrothermal Conditions | 10.1007/s12221-023-00262-0 |
2023-08-01 | In this paper, the linear low-density polyethylene (LLDPE) fibers were used as the precursors to prepare low-cost carbon fibers (CFs) via ultraviolet crosslinking-vulcanized stabilization-carbonization processing. The spinning particles were obtained by mixing linear low-density polyethylene with photoinitiator 4-chlorobenzophenone (4-CBP), crosslinkers triallyl isocyanurate (TAIC), and thermal stabilizer antioxidant 1010, and then the ultraviolet (UV) photosensitive LLDPE fibers were fabricated by traditional melt spinning. Then, the LLDPE primary fibers were treated by UV irradiation, vulcanized stabilization and carbonization to obtain the low-cost CFs. to characterize the structure and properties of ultraviolet crosslinked polyethylene (UV-XLPE) fibers and CFs, the Fourier transform infrared spectrometer, differential scanning calorimeter, thermogravimetric analyzer, X-ray diffractometer and scanning electron microscope were adopted. The results showed that, UV irradiation introduced a crosslinked structure of LLDPE fibers, and the degree of gelation of XLPE fibers reached a maximum of 48.6% when UV irradiation was carried out for 15 min; with the extension of UV irradiation time, the melting temperature and crystallization temperature of UV-XLPE fibers move to the direction of low temperature, and the crystal size of the fiber decreases; after vulcanization, the carbon yield of the fiber is significantly improved, reaching up to 62.9%, and the surface and section of CFs are dense. | Fabrication of liner low-density polyvinyl-based carbon fibers via ultraviolet irradiation-vulcanization crosslinking | 10.1007/s00396-023-05110-4 |
2023-08-01 | Sulfide electrolyte-based all-solid-state batteries (ASSBs) are potential next generation energy storage technology due to the high ionic conductivity of sulfide electrolytes and potentially improved energy density and safety. However, the performance of ASSBs at/below subzero temperatures has not been explored systematically. Herein, low temperature (LT) performance of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811)|Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 (LiSPSCl)|Li 4 Ti 5 O 12 (LTO) ASSBs was investigated. By charging the ASSB to 6 V at −40 °C, a capacity of 100.7 mAh·g −1 at 20 mA·g −1 was achieved, which is much higher than that charged to 4.3 V (4.6 mAh·g −1 ) at −40 °C. Moreover, atomic resolution microscopy revealed that the NCM811 remained almost intact even after being charged to 6 V. In contrast, NCM811 was entirely destructed when charged to 6 V at room temperature. The sharp difference arises from the large internal charge transfer resistance at LT which requires high voltage to overcome. Nevertheless, such high voltage is not harmful to the active material but beneficial to extracting most energy out of the ASSBs at LT. We also demonstrated that thinner electrolyte is favorable for LT operation of ASSBs due to the reduced ion transfer distance. This work provides new strategies to boost the capacity and energy density of sulfide-based ASSBs at LT for dedicated LT applications. | Boosting the energy density of sulfide-based all-solid-state batteries at low temperatures by charging to high voltages up to 6 V | 10.1007/s12274-023-5827-3 |
2023-08-01 | Abstract The development of low-temperature sol–gel (solution) processes for the fabrication of crystalline metal oxide thin films has become a key objective in the emerging Flexible Electronics. To achieve this target, crystalline oxide films need to be deposited on flexible substrates, which have degradation temperatures below 350 °C (e.g., polymers or textile). This achievement would be a step towards improving the performance of the flexible device, making feasible applications now restrained (e.g. smart-skin, flexible-displays or solar-cells) and whose performance is associated to the functional properties of the crystalline oxide (e.g., ferroelectricity, pyroelectricity or piezoelectricity). However, this is a challenge because the crystallization of these oxides usually occurs at high temperatures, over 600 °C. This paper shows an overview to the solution strategies devised in our group for the low-temperature fabrication of crystalline metal oxide thin films, mostly ferroelectric perovskites (e.g., BiFeO 3 , PbTiO 3 or Pb(Zr,Ti)O 3 ). We have made use of UV-light as an alternative energy source to the thermal energy conventionally used to obtain the crystalline oxide. High photosensitive sol–gel solutions have been synthesized and the solution-deposited layers irradiated with UV-excimer lamps. A precise control of the photoreactions occurring during the irradiation of these layers has been carried out with the aim of advancing the formation of a high-densified, defect-free amorphous metal oxide film that easily can be converted into crystalline at temperatures compatible with the use of polymer substrates. Graphical Abstract An overview to the solution strategies devised in our group for the low-temperature fabrication of crystalline metal oxide thin films, mostly ferroelectric perovskites, is shown in this article. UV-light is used as an alternative energy source to the conventional thermal energy used to obtain crystalline oxide thin films. These solution strategies are based in the synthesis of high photosensitive sol–gel solutions and the irradiation of the solution-deposited layers with UV-excimer lamps under controlled irradiation atmospheres. A precise control of the photoreactions occurring in the system during the irradiation process has been carried out, with the aim of advancing the formation of high-densified, defect-free amorphous metal oxide films able to be converted into crystalline at temperatures compatible with the use of polymer substrates. This makes possible the integration of these advanced materials in the emerging Flexible Electronics. Low-temperature sol–gel (solution) methods for the fabrication of crystalline metal oxide films. UV-light-assisted Chemical Solution Deposition of films for accelerating the oxide crystallization. Thin film crystallization at temperatures ≤350 °C on flexible polyimide substrates. Functional properties of crystalline metal oxide films on flexible polyimide substrates. | Low-temperature sol–gel methods for the integration of crystalline metal oxide thin films in flexible electronics | 10.1007/s10971-023-06065-2 |
2023-08-01 | Abstract The processes of degradation of the initial strength properties of polycrystalline structural alloys are considered under mechanisms that combine low-cycle fatigue and long-term strength of the material. From the point of view of mechanics of damaged medium (MDM) and fracture mechanics (FM), a mathematical model that describes the processes of cyclic viscoplastic deformation and damage accumulation in structural alloys under multiaxial disproportionate modes of combined thermomechanical loading has been developed. The model consists of three interrelated components: relations that determine the cyclic viscoplastic behavior of the material by taking into account the dependence on the fracture process; evolutionary equations describing the kinetics of damage accumulation; criterion of the strength of the damaged material. The viscoplasticity model is based on the idea of the existence of plasticity and creep surfaces in stress space and the principle of gradient vectors of plastic and creep strain rates to the corresponding surface at the loading point. This form of the equations of state reflects the main effects of cyclic viscoplastic deformation of the material for arbitrary complex loading trajectories. The form of kinetic equations for damage accumulation is based on the introduction of a scalar damage parameter and on energy principles. It also takes into account the main effects of the formation, growth and merging of microdefects under arbitrary complex modes of combined thermomechanical loading. A joint form of the evolutionary equation for damage accumulation in the areas of low-cycle fatigue and long-term strength of the material is proposed. As a criterion for the strength of a damaged material, the condition for reaching a critical value is used. The material parameters and scalar functions included in the constitutive relations of the MDM mathematical model are obtained. The results of numerical simulation of the processes of deformation and damage accumulation in structural alloys under the mutual influence of low-cycle fatigue and long-term strength of the material are presented. The results of comparison of calculated and experimental data show that the proposed MDM model qualitatively and with the accuracy necessary for practical calculations quantitatively describes the durability of materials under the mutual influence of low-cycle fatigue and long-term strength of the material. | Calculation of Life Characteristics for Structural Alloys under the Mutual Influence of Fatigue and Long-Term Strength | 10.3103/S0025654423700152 |
2023-08-01 | Environmental variation is the most crucial problem as it is causing food insecurity and negatively impacts food availability, utilization, assessment, and stability. Wheat is the largest and extensively cultivated staple food crop for fulfilling global food requirements. Abiotic stresses including salinity, heavy metal toxicity, drought, extreme temperatures, and oxidative stresses being the primary cause of productivity loss are a serious threat to agronomy. Cold stress is a foremost ecological constraint that is extremely influencing plant development, and yield. It is extremely hampering the propagative development of plant life. The structure and function of plant cells depend on the cell's immune system. The stresses due to cold, affect fluid in the plasma membrane and change it into crystals or a solid gel phase. Plants being sessile in nature have evolved progressive systems that permit them to acclimatize the cold stress at the physiological as well as molecular levels. The phenomenon of acclimatisation of plants to cold stress has been investigated for the last 10 years. Studying cold tolerance is critical for extending the adaptability zones of perennial grasses. In the present review, we have elaborated the current improvement of cold tolerance in plants from molecular and physiological viewpoints, such as hormones, the role of the posttranscriptional gene, micro RNAs, ICE-CBF-COR signaling route in cold acclimatization and how they are stimulating the expression of underlying genes encoding osmoregulatory elements and strategies to improve cold tolerance in wheat. | Molecular and genetic perspectives of cold tolerance in wheat | 10.1007/s11033-023-08584-1 |
2023-08-01 | The impact of water pollution has led to the search for cost-effective and environmentally friendly treatment processes to alleviate the associated environmental hazards. Adsorption is identified as an advanced treatment technology that offers simplicity and cheap alternatives to water treatment technologies when low-cost adsorbents such as industrial by-products, waste, and agricultural waste are utilized. The utilization of these materials as low-cost adsorbents for the treatment of drinking water will bring them some value. Several practices have been done to improve the removal efficiencies of the low-cost adsorbents in order to achieve WHO standards of drinking water quality. The paper highlights some of the synthesis routes employed for the modification of low-cost adsorbents. This updated review provides information on the different applications of low-cost adsorbents in removing pollutants and their adsorption capacities in an attempt to deploy the recent sustainable low-cost adsorbents with high removal efficiencies for water treatment. Future research should focus on the fabrication of hybrid low-cost adsorbents with multifunctional and antimicrobial properties. In addition, life cycle assessment (LCA) should be conducted to reveal the environmental burdens associated with the modification of the low-cost adsorbent to improve their removal efficiencies. | Application of conventional and emerging low-cost adsorbents as sustainable materials for removal of contaminants from water | 10.1007/s11356-023-28399-8 |
2023-08-01 | Low-permittivity microwave dielectric ceramics could improve the transmission rate of devices. It is important to explore low-permittivity materials with excellent performances. In this paper, a low-permittivity microwave dielectric ceramic Na 2 Ba 6 Si 4 O 15 (NBSO) was prepared by a solid-state reaction method. NBSO ceramics belong to a monoclinic system (space group: P2 1 /c). With the increase of sintering temperature, the bulk density and relative density of ceramics also increases. The Q × f is explained by analysis of the packing fraction of NBSO ceramics. When the sintering temperature was 975°C, the packing fraction of the NBSO ceramic reached the maximum values of 57.38%. At the same time, the Q × f value of NBSO reaches its maximum. In addition, the τ ƒ value is affected by bond valence. The NBSO ceramic has good microwave dielectric performances of ε r = 8.81, Q × f = 26,346 GHz, τ ƒ = − 9.21 ppm/°C) and a low sintering temperature, indicating that it is a strong candidate in the field of low-temperature co-firing technology and has good application prospects in the field of mobile communication base stations. | Effects of Sintering Behavior, Structure, Packing Fraction, and Bond Valence on the Microwave Dielectric Properties of Low-Permittivity Na2Ba6Si4O15 Ceramics | 10.1007/s11664-023-10489-5 |
2023-08-01 | The semi-dry flue gas desulfurization ash (SFGDA) is an industrial waste generated by the semi-dry desulfurization process, and its resources have been continuously attracted attention. Through the method of heat decomposition, the SFGDA decomposed into CaO and SO 2 has emerged as a prominent research topic. This paper summarizes various of research workers, who revealed that the decomposition temperature of CaSO 4 in SFGDA is greater than 1678 K and 1603 K in the air atmosphere and N 2 atmosphere, respectively, presenting challenges such as high energy consumption and limited economic feasibility. On the one hand, the effects of CO and C regulating the pyrolysis atmosphere on reducing the pyrolysis temperature were reviewed. On the other hand, the impact of additives such as Fe 2 O 3 and FeS 2 was considered. Ultimately, the joint effects of regulating atmosphere and additives were discussed, and an efficient and low-temperature decomposition route was obtained; adding solid C source and Fe 2 O 3 for pyrolysis reaction, the decomposition temperature of CaSO 4 can be reduced by at least 230 K and desulfurization efficiency exceeds 95% under the condition of micro-oxidizing atmosphere. Moreover, the CaO resulting from SFGDA decomposition can be further synthesized into calcium ferrite, while the enriched SO 2 can be utilized for the production of industrial sulfuric acid, which holds promising prospects for large-scale industrial applications. | Advances on resource utilization of semi-dry desulfurization ash by thermal decomposition: a high-efficiency and low-temperature method for large-scale processing | 10.1007/s11356-023-28818-w |
2023-08-01 | The aim of this study was to synthesize a bio-based cured epoxy resin using acetone-soluble lignin, a low-molecular-weight lignin, obtained from steam-exploded wheat straw. Wheat straw, an agricultural waste, was steam-exploded at a steam pressure of 2.5 MPa (225 °C) for a steaming time of 5 min, following which it was extracted first with water and then with acetone, to obtain low-molecular-weight lignin. Lignin epoxy resin was synthesized by the reaction of acetone-soluble lignin with epichlorohydrin and then cross-linked with two kinds of curing agents, acetone-soluble lignin or petroleum-derived phenol novolac, to obtain cured lignin epoxy resins. Furthermore, ligno-p-cresol epoxy resin was synthesized using lingo-p-cresol that is made of acetone-soluble lignin and p-cresol, to improve the thermal and mechanical properties of the cured epoxy resin, using ligno-p-cresol epoxy resin instead of lignin epoxy resin. The thermal decomposition temperatures at 5% weight loss and the tensile strength of all lignin-derived bio-based curing epoxy resins obtained in this study exceeded 250 °C and 27 MPa, respectively, which are required for application in the electronic substrate material field. The cured epoxy resin synthesized from EP828 (a commercial fossil resource-derived epoxy resin) and ligno-p-cresol increased 10% weight loss and tensile strength, compared to that synthesized from EP828 and acetone-soluble lignin. Additionally, its tensile strength was almost the same as that of the fossil resource-derived cured epoxy resin synthesized from EP828 and TD2131 (a commercial fossil resource-derived curing agent). Graphical abstract | Cured epoxy resin synthesized using acetone-soluble lignin and ligno-p-cresol obtained from steam-exploded wheat straw | 10.1007/s13399-021-02032-5 |
2023-08-01 | Phosphogypsum (PG), which has great environmental harm and restricts the sustainable development of phosphorus chemical industry, is a solid waste produced in phosphoric acid production. Thermal decomposition of PG is an extensive way to reutilization of resource, and the key point is to establish an appropriate decomposition path and catalyst system of PG. In the work, the strategy for low-temperature and highly-efficient decomposition of PG is established based on the thermodynamic analysis and the experimental research by metal ions to reduce the decomposition temperature. Meanwhile, SEM(Scanning Electron Microscope) is used to characterize the composition and morphology of PG in the various conditions, also the decomposition temperature is analyzed by TGA(Thermogravimetric Analysis). Then, the decomposition ratio via Fe 3+ /Co 2+ /Ni 2+ unitary/ternary catalyst is obtained by precipitation method. Through kinetic analysis combined with XRF(X-ray Fluorescence Spectrometer) and EDX(Energy Dispersive X-Ray Spectroscopy) results, it is found that there is a reaction competition in the decomposition process by Fe 3+ /Co 2+ /Ni 2+ ternary catalyst. Further the mechanism of catalytic system on PG is derived. The present work can be concluded that Fe 3+ /Co 2+ /Ni 2+ can effectively reduce the decomposition temperature of PG, and the effect of ternary metal is more obvious than that of unitary metal. Finally, pomelo peel is used instead of coke to successfully decompose PG at low temperature by one step method. The establishment of low temperature decomposition system of PG has potential application in phosphorus chemical industry and is in line with sustainable development. | Low temperature and highly-efficient one-step decomposition of phosphogypsum via biochar by Fe3+/Co2+/Ni2+ unitary/ternary catalyst | 10.1007/s11356-023-28754-9 |
2023-08-01 | Increasing demand for manganese and rapid depletion of high-grade manganese ores grow attention to other resources. However, environmental impacts and techno-economic issues are the main challenges regarding manganese extraction from low-grade ores. This study investigated the environmental impacts of manganese recovery from low-grade ores and the synthesis of magnetic manganese ferrite. Two methods of synthesis were selected, a high-temperature synthesis using a furnace and a low-temperature method where the aging process compensates for the absence of a high-temperature regime. Life cycle analysis was conducted through the collected data to quantify and compare the environmental impacts. The high-temperature synthesis method surpassed the other process in almost all environmental categories adopted in the TRACI model. Additionally, sodium hydroxide has almost the highest contribution in both synthesis methods, while in the recovery process, electricity was the major contributor to all environmental categories. Besides electricity, sulfuric acid and sulfur dioxide play essential roles in the environmental impacts of the recovery process. Therefore, the low-temperature synthesis of manganese ferrite as a novel method is cost-effective and warrants the least environmental footprint. | Assessing the environmental footprints of the manganese recovery process from low-grade ore to synthesize manganese ferrite | 10.1007/s10098-023-02488-1 |
2023-08-01 | Mine tailings contain finer particles, crushed rocks, dugout-soil, water, and organic and inorganic metals or metalloids, including heavy metals and radionuclides, which are dumped as waste or non-economic by-products generated during mining and mineral processing. These abundant and untreated materials seriously threaten the environment, human health, and biodiversity because of the presence of heavy metals, radionuclides, and associated primary and secondary toxic components, including the risk of tailings dam failures. Biocementation technology, which involves the use of mining microbes to secrete cement-like materials that bind soil particles together, is a promising approach to restore mine tailing sites and reduce their mobility and toxicity. However, there is a lack of literature on the combined interactions among mining microbes, tailings residues, biocementation, and low-carbon cement (LCC) prospects. This comprehensive review article explores the prospects of mining microbes for mine tailings restoration using biocementation technology, the key influencing factors and their impact, mechanisms and metabolic pathways, and the effectiveness of biocementation technology in restoring mine tailings sites. In addition, it reviews the utilization of mine tailings materials as an alternative source of cement or construction materials for LCC technology. Furthermore, this review highlights the important issues, challenges, limitations, and applications of biocementation technology for mine tailings rehabilitation. Finally, it provides insights for future research and implementation of biocementation for mine tailings restoration and utilization of tailing materials in the industrial sector to reduce carbon emissions/footprints and achieve net-zero goals. | Unlocking the potential of microbes: biocementation technology for mine tailings restoration — a comprehensive review | 10.1007/s11356-023-28937-4 |
2023-08-01 | The synthesis of δ-MnO 2 , δ-MnO 2 carbon dots nanocomposite, and Fe/Cu-doped δ-MnO 2 carbon dots nanocomposite has been successfully carried out through a stirring process at room temperature and 80 °C. The synthesized powder shows a low crystallization determined through XRD and TEM analysis. Furthermore, the carbon dots are well attached to MnO 2 performing a core–shell composite material, while the doping ions Fe and Cu were incorporated into the matrix substitute Mn in the MnO 6 octahedron, although potassium ions were also detected. The manganese possess an oxidation state of + 3 and + 4, which promotes the oxygen vacancy creation $${V}_{\mathrm{O}}^{\cdot\cdot}$$ V O · · denoting the conductivity decrease. | Low-temperature synthesis of doped MnO2–carbon dots nanocomposite: an analysis of nanostructure and electrical properties | 10.1007/s40243-023-00237-4 |
2023-08-01 | The influence of low-temperature superplastic deformation on the structural-phase state and mechanical properties of ultrafine-grained titanium alloy VT22 has been studied at room temperature. It is shown that the tensile strain of alloy samples has an insignificant effect on their mechanical properties at strain rates of 2·10 –3 and 6.9·1 –3 s –1 and a temperature of 823 K. It has been established that this effect is due to the preservation of the ultra fine grade (UFG) structural-phase state of the alloy during superplastic deformation formed as a result of its processing by the method of all-round pressing. An increase in the deformation temperature to 873 K at the same strain rates leads to a decrease in the mechanical properties of the alloy by about 6–8%. | Influence of Low-Temperature Superplastic Deformation on the Structural-Phase State and Mechanical Properties of the Ultrafine-Grained VT22 Alloy | 10.1007/s11182-023-02951-y |
2023-08-01 | Abstract The results of experimental studies of solid lubricating coatings for space applications, in particular, one of the most effective coatings EONIT-3, are presented. The coefficients of friction of coatings and wear resistance at temperatures from minus 150 to plus 400°C in air and in vacuum 10 –6 mm Hg were studied for various combinations of antifriction materials depending on the contact pressure, sliding speed, indenter—disk and shaft—sleeve test patterns. It is shown that in tribochemical process molybdenum disulfide, the main industrial solid lubricant, plays the role of an active catalyst. Optimal and stable antifriction and physico-mechanical properties of the EONIT-3 coatings are observed after two hours of heat treatment at 200°C. | Tribotechnical Characteristics of Solid Lubricating Coatings | 10.3103/S1068366623040037 |
2023-08-01 | Because of the increase in the transmission voltage levels, the demand for insulation reliability of power transformers has increasingly become critical. Cellulose insulating paper is the main insulating component of power transformers. To improve the insulation level of ultrahigh voltage transformers and reduce their weight and size, reducing the dielectric constant of oil-immersed cellulose insulating paper is highly desired. Cellulose is used to produce power-transformer insulating papers owing to its excellent electrical properties, renewability, biodegradability and abundance. The dielectric constant of a cellulose insulating paper can be effectively reduced by chemical or physical modification. This study presents an overview of the foreign and domestic research status of the use of modification technology to reduce the dielectric constant of cellulose insulating papers. All the mentioned methods are analyzed in this study. Finally, some recommendations for future modified cellulose insulating paper research and applications are proposed. This paper can provide a reference for further research on low dielectric constant cellulose insulating paper in the future. | Research progress on low dielectric constant modification of cellulose insulating paper for power transformers | 10.1007/s11705-022-2259-7 |
2023-08-01 | Due to the high viscosity, rubber asphalt displays poor construction workability, which ultimately compromises the comfort and safety of pavement. In this study, specified control variates were used to study the effect of the waste engine oil (WEO) addition sequence on the properties of rubber asphalt while ensuring the consistency of other preparation parameters. Initially, in order to evaluate their compatibility, the storage stability and aging properties of the three groups of samples were determined. The variation of asphalt viscosity was then analyzed using a low-field nuclear magnetic resonance (LF-NMR) test, by predicting the fluidity of each sample. Subsequently, the results showed that the rubber asphalt prepared by premixing WEO and crumb rubber (CR) had the best properties of low temperature, compatibility, and fluidity. On this basis, the effects of WEO content, shear rate, shear temperature, and shear time on the properties of low viscosity rubber asphalt were investigated separately through response surface methodology (RSM). Quantitative data from the basic performance experiment were used to fit the high precision regression equation, thereby correlating a more precise level of factors with experimental results. The response surface model prediction analysis showed that the optimal preparation parameters of the low viscosity rubber asphalt were 60 min shear time, 180 °C shear temperature, and 5000 r/min shear rate. Simultaneously, the addition of 3.5% of WEO showed great potential as an asphalt viscosity reducer. Ultimately, this study provides an accurate method for determining the optimum preparation parameters of asphalt. | Optimizing parameters for the preparation of low viscosity rubber asphalt incorporating waste engine oil using response surface methodology | 10.1007/s11356-023-28383-2 |
2023-08-01 | Acid dew point is the temperature at which the sulfuric acid vapor in flue gas begins to condense. Acid condensation can result in low-temperature corrosion that occurs on the convective heating surfaces. Low-temperature corrosion often leads to a disruption in the normal operation of heating surfaces, even failures, and a significant decrease in the efficiency of the entire boiler. Authors used a method for calculating acid dew point of flue gases based on the conditions of thermodynamic equilibrium of chemical processes involving the transformation of compounds contained in flue gases, and the thermodynamic equilibrium of a multicomponent multiphase system, which is the flue gases. Based on the proposed methodology, a mathematical model has been developed. The authors developed a mathematical model of the boiler BKZ-75-39FB with the calculation of the abrasive wear of convective heating surfaces, the proportion of sulfur oxides bound by the fly ash of the fuel and by the sulfur-binding component, low-temperature corrosion rate for the purpose of a comprehensive assessment of the possibility of introducing this technical solution. The calculation of the acid dew point in the study is close to the actual ones. | Determination of Acid Dew Point Based on the Calculation of Thermodynamic Equilibrium of Chemical Reactions of the Sulfuric Acid Formation Given the Condensed State | 10.1007/s41660-023-00328-9 |
2023-08-01 | Ba 0.7 Sr 0.3 TiO 3 added with 1 mol% B 3+ and x mol% Mn 2+ (BSTBM) ceramics were synthesized using citrate combustion technique. An enhanced electrocaloric effect has been reported in BSTBM ceramic. The addition of B 3+ and Mn 2+ ions lowers the sintering temperature of BSTBM ceramics to 1200 °C. The ceramic sample with x = 0.5 exhibits homogeneous grain size, low dielectric loss and large polarization. More importantly, the ceramic sample with x = 0.5 shows the excellent electrocaloric properties (adiabatic temperature change, Δ T = 0.86 K, and electrocaloric responsivity, Δ T /Δ E = 0.43 K m MV −1 ) under electric field of 20 kV/cm and room temperature. Moreover, a high Δ T of 3.08 K and Δ T /Δ E of 0.31 K m MV −1 are obtained under electric field of 100 kV/cm near room temperature for this composition. Graphical Abstract Ba 0.7 Sr 0.3 TiO 3 added with 1 mol% B 3+ and x mol% Mn 2+ (BSTBM, x = 0.3, 0.5, 1.0 and 1.5) ceramics were synthesized using citrate combustion technique. Different content of Mn 2+ ions were introduced into BST ceramics, and the electrical properties were studied. Moreover, the electric field dependence of the electrocaloric behaviors were studied systematically. Our work demonstrates that B 3+ + Mn 2+ is more promising improve the sintering condition of BST ceramics and serves as an effective and environmental-friendly additive to induce higher room-temperature ECE performances under low fields. The addition of B 3+ and Mn 2+ lowers the sintering temperature of BSTBM ceramic. Improved microstructure and enhanced electrocaloric properties are realized. Large adiabatic temperature change Δ T = 3.08 K is obtained at 100 kV/cm. Δ T = 0.86 K and Δ T /Δ E = 0.43 K m MV −1 are realized at 37.5 °C and 20 kV/cm. | Improved electrocaloric effect of Ba0.7Sr0.3TiO3 ceramics doped with B and Mn | 10.1007/s10971-023-06135-5 |
2023-08-01 | Abstract In this study, a novel mesoporous adsorption composite namely G-SMS/ZIF-67(C) was synthesized by coating the ZIF-67 doped with graphene oxide (GO) on the surface of spherical mesoporous silica (SMS) and finally modified by high-temperature calcination. Compared with activated carbon (AC), the synthesized adsorption composite exhibited a good adsorption capacity of methyl orange (MO) in low-temperature aqueous environment. The adsorption process was consistent with the pseudo-first-order kinetics and Freundlich model. It revealed that the formed mesoporous structure and hydrophobic interactions of the G-SMS/ZIF-67(C) after calcination effectively improved the adsorption performance, with the average adsorption rate and maximal adsorption capacity of G-SMS/ZIF-67(C) 1.8 and 2.91 times higher than that of the ones without calcination, respectively. Moreover, the maximal adsorption capacity of the G‑SMS/ZIF-67(C) composite was positively correlated with the temperature. The thermodynamics and mechanism of the adsorption process have been investigated and rationalized. | Dye Adsorption Study of ZIF-67 Mesoporous Composite with Strong Hydrophobic Effect in Low-Temperature Aqueous Environment | 10.1134/S0036024423080174 |
2023-08-01 | A garbage truck caught fire while in service. The fire investigation following the incident determined that the origin of the fire was in the front of the truck, in an area where a hydraulic tube had burst. This paper presents the metallurgical analysis which was conducted on the burst tube to determine whether the failure was the cause or the consequence of the fire. Visual examination revealed that the hydraulic tube failed because of a short-term high-temperature (thin-lip) fracture. Chemical analysis and hardness measurements confirmed that the tube was made of low-carbon steel, consistent with a hydraulic tube. Microscopic examination of a sample from the tube, taken far from and close to the fracture, revealed that the tube had undergone transformations which typically occur when steel is exposed to high temperatures, such as pearlite spheroidization and bainite transformation. These transformations were consistent with the overheating of the tube from its external surface, which was in turn consistent with the fire. | Metallurgical Analysis as a Tool in Fire Investigations: A Case Study | 10.1007/s11668-023-01694-9 |
2023-08-01 | A series of x Ce-MnO 2 ( x = 0–1) catalysts were synthesized using ammonium oxalate as a precipitator via the redox precipitation method and hydrothermal synthesis method. The results indicate that 0.25Ce-MnO 2 exhibited the highest catalytic activity for toluene oxidation, with the T 99 of 240 °C. Characterization results from XRD, Raman, SEM, TEM, EDS-mapping, BET, and other techniques reveal that the 0.25Ce-MnO 2 catalyst exhibited a three-dimensional multistage ultrathin nanosheet structure by adjusting the introduction amount of Ce, with abundant active sites, and effectively formed Ce-Mn homogeneous dispersion. The larger pore size and volume of 0.25Ce-MnO 2 catalyst lead to it excellent toluene transfer ability. Furthermore, compared with MnO 2 , the crystal pattern of 0.25Ce-MnO 2 shifted to the tetragonal cryptomelane type α-MnO 2 phase and exposed more crystal planes which are beneficial to catalyze toluene. H 2 -TPR, O 2 -TPD, and XPS characterization further confirmed the strong interaction between Ce and Mn oxides, which exhibited better low-temperature reducibility and oxygen migration, along with abundant Ce 3+ and Mn 3+ species, where lattice oxygen played a major role. Moreover, in situ DRIFTS revealed that the 0.25Ce-MnO 2 catalyst showed higher adsorption and desorption capacity for toluene than the MnO 2 catalyst, and benzoate species were the key intermediates for catalytic oxidation. Additionally, benzoate and surface phenolic species were the key intermediates for catalytic oxidation of MnO 2 . Because 0.25Ce-MnO 2 possesses better ability of converting toluene to benzoate species, it exhibits better activity. | Synthesis of xCe–MnO2 with three-dimensional ultra-thin nanosheet structure and its excellent low-temperature reducibility for toluene catalysis | 10.1007/s11356-023-28715-2 |
2023-08-01 | The present work aims to exploit the zero-cost inducer bread waste (BW) for the production of cold-adapted α-amylase (CA-AM21) by the hyperproducer marine psychrotolerant Glutamicibacter soli strain AM6 EMCCN 3074. Incubation temperature (20 °C), incubation time, BW, (NH 4 ) 2 SO 4 , and modified seawater-based minimal medium were inferred to be significant factors influencing CAM-21 production in OVAT and Plackett-Burman investigations. BW (3.8%w/v), (NH 4 ) 2 SO 4 (0.098%w/v), and incubation time (2.329 days) prompted CA-AM21 (56.85 U/mL) with 7.58-fold enhancement, Box-Behnken design, and ridge steepest ascent path inferences. A two-step strategy was used to purify CA-AM21: fractional (NH 4 ) 2 SO 4 precipitation (60-80%) and a starch affinity chromatography. Specific activity, yield, and fold purification of purified CA-AM21 were 884.5 U/mg, 12.45%, and 285.3, respectively. CA-AM21 exhibited an approximate molecular mass of 14 kDa, deduced from SDS-PAGE analyses. The pH and temperature optimums for CA-AM21 were 7.0 and 40 °C, respectively. At 5–25 °C, full activity was maintained after 2 h. At pH 6.0–8.0, almost full activity (90–100%) was retained after 15 h. CA-AM21 demonstrated full stability after 30 min at 1.0–5.0 M NaCl, with 200% increased activity at 1.0–4.0 M NaCl. Full stability of CA-AM21 in the presence of non-ionic detergents, such as Tween 20, Tween 80, and Triton X-100, with 100% activity sustained after 30 min was retained. On soluble starch, purified CA-AM21 exhibited km and Vmax of 0.039 mg.mL −1 and 115.71 μmol glucose. min −1 . mg −1 , respectively. The purified CA-AM21 demonstrated remarkable significant washing efficiency with commercial laundry detergents thus implying its applicability for detergent formulations. | Bioconversion of bread waste by marine psychrotolerant Glutamicibacter soli strain AM6 to a value-added product: cold-adapted, salt-tolerant, and detergent-stable α-amylase (CA-AM21) | 10.1007/s13399-022-02325-3 |
2023-08-01 | The investigation of the ZCu 2+ (OH) − and Z 2 Cu 2+ ions modifications during NH 3 -SCR on Cu–CHA catalysts is a key aspect to clarify the still-debated low-T redox SCR mechanism. In previous works, the dry transient CO oxidation protocol has been employed to identify the generation of dinuclear Cu 2+ structures under conditions representative of the low-T SCR–RHC: NH 3 solvation promotes the inter-cage mobility and coupling of ZCu 2+ (OH) − , acting as the catalytic centers for the CO oxidation process, while Z 2 Cu 2+ results inactive. Herein the same protocol, with pre-stored NH 3 , has been applied to a set of Cu–CHA catalysts with variable Cu loading (0.7–2.4% w/w) but fixed Si/Al: an increasing Cu content produced a net positive effect on the CO 2 production, coherent with a growing ZCu 2+ (OH) − population, while a further enhancement was observed in the presence of H 2 O. The analysis of the integral CO 2 production enabled to predict the maximum CO conversion, corresponding to the titration of the whole ZCu 2+ (OH) − content for each catalyst under dry condition, verifying the initial mechanism. Conversely, in the presence of water, the analysis evaluated an asymptotic titration of the total catalyst Cu 2+ contents. This finding permits to generalize a recent study where combined TRMs, DFT and FTIR were used to probe the complete reversible Cu 2+ sites hydrolysis and pairing in the presence of H 2 O and NH 3 , thus activating the participation of Z 2 Cu 2+ species, too. These results also highlight the versatility and effectiveness of the CO oxidation protocol as a multi-purpose technique to study the Cu 2+ ions in Cu–CHA catalysts. | Transient CO Oxidation as a Versatile Technique to Investigate Cu2+ Titration, Speciation and Sites Hydrolysis on Cu–CHA Catalysts: The Cu Loading Effect | 10.1007/s11244-023-01813-8 |
2023-08-01 | Abstract Water contamination is primarily caused by effluent from the textile sector. The highly toxic and non-biodegradable nature of pollutants in the effluent makes it challenging to remove these compounds, which therefore poses harm to the environment. An effective technology, biosorption, may be a viable method for mineralizing hazardous contaminants from wastewater. Water hyacinth is one of several inexpensive adsorbents that is a fast-growing, widely accessible plant with high removal rates. A catalyst called cetyl trimethyl ammonium bromide was used to activate the biosorbent. By using the central composite design of response surface methodology and the adsorbate as a synthetic wastewater, ideal conditions of significant parameters, including temperature, pH, sorbent dosage, and contact duration were obtained. The real textile effluent was subjected to the ideal conditions and adsorption efficiency of 92.88 ± 0.5% was attained. Chemical oxygen demand of the effluent was reduced by 50% after the biosorption. The attribution of functional groups in the adsorbent to different wavenumbers was made evident through the Fourier-transform Infrared Spectroscopy analysis, and the morphology and porous structure of the biosorbent were shown through scanning electron microscopy. In order to potentially act as an adsorbent for the biosorption of pollutants from textile effluents, surface-modified water hyacinth root powder could be employed. | Investigation of Biosorption Properties of Water Hyacinth Root in Textile Effluent and Synthetic Wastewater Treatment | 10.3103/S1063455X23040112 |
2023-08-01 | Abstract The refractory metal carbides TiC, ZrC, HfC, NbC, and TaC have excellent physical, chemical, and mechanical properties as materials for ultra-high temperature ceramics. The most refractory of them are TaC and HfC, the melting temperatures of which approach 4000°C. The high hardness, strength, and wear resistance of refractory carbides is also noteworthy. Therefore, natural interest in high-entropy carbides (HECs) based on them is grounded: they are becoming an important class of new ceramic materials, since they potentially have more advanced applied properties. However, the production of such materials by classical metallurgical methods is a difficult problem. In modern investigations, HEC samples are most often synthesized using expensive special equipment (plasma spark sintering methods, high-energy planetary mills, etc.) and relatively long preparation of precursors for sample fabrication. Here, we describe a new approach to synthesizing a multicomponent (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2 )C carbide using an electrochemical process at a temperature not exceeding 1173 K. This technique is based on the phenomenon of currentless metal transfer in molten salts. After sequential metal transfer, the sample is washed from an electrolyte and then sintered in a vacuum furnace. According to X-ray diffraction analysis, the resulting HEC is a single-phase fcc solid solution. The X-ray diffraction pattern of the synthesized sample is in good agreement with the X-ray diffraction pattern calculated by the Debye formula for a supercell of 64 000 atoms. A compacted HEC sample is prepared by pressing a pellet 10 mm in diameter in a mold with the addition of cobalt as a matrix metal. After vacuum sintering, the sample is polished for examination in a scanning electron microscope. Elemental mapping of the sample surface is performed; it demonstrates a satisfactory distribution of the metals that make up the HEC. The measured microhardness of the sample turned out to be lower than the values reported by other authors, which can be due to some residual porosity of the sample. | Method for Synthesizing a High-Entropy Carbide in an Ionic Melt | 10.1134/S003602952308030X |
2023-08-01 | Abstract While the in situ return of corn straw can improve soil fertility and farmland ecology, additional bacterial agents are required in low-temperature areas of northern China to accelerate straw degradation. Moisture is an important factor affecting microbial activity; however, owing to a lack of bacterial agents adapted to low-temperature complex soil environments, the effects of soil moisture on the interaction between exogenous bacterial agents and indigenous soil microorganisms remain unclear. To this end, we explored the effect of the compound bacterial agent CFF constructed using Pseudomonas putida and Acinetobacter lwoffii , developed to degrade corn straw in low-temperature soils (15 °C), on indigenous bacterial and fungal communities under dry (10% moisture content), slightly wet (20%), and wet (30%) soil-moisture conditions. The results showed that CFF application significantly affected the α-diversity of bacterial communities and changed both bacterial and fungal community structures, enhancing the correlation between microbial communities and soil-moisture content. CFF application also changed the network structure and the species of key microbial taxa, promoting more linkages among microbial genera. Notably, with an increase in soil moisture, CFF enhanced the rate of corn straw degradation by inducing positive interactions between bacterial and fungal genera and enriching straw degradation-related microbial taxa. Overall, our study demonstrates the alteration of indigenous microbial communities using bacterial agents (CFF) to overcome the limitations of indigenous microorganisms for in situ straw-return agriculture in low-temperature areas. Key points • Low-temperature and variable moisture conditions (10–30%) were compared • Soil microbial network structure and linkages between genera were altered • CFF improves straw degradation via positive interactions between soil microbes | Low-temperature corn straw-degrading bacterial agent and moisture effects on indigenous microbes | 10.1007/s00253-023-12644-8 |
2023-08-01 | Ceramic membranes are considered more effective for wastewater treatment applications than polymeric membranes because of their excellent resistance to thermal and chemical environments and possess high durability. To avoid the high cost of commercial ceramic membranes, recently, a significant improvement has been accomplished in developing them using low-cost alternative materials and their application in wastewater treatment. This study investigated the performance of an innovative ceramic microfiltration (MF) membrane fabricated with inexpensive Fuller's earth clay in treating the natural raw rubber (ribbed smoked sheet)-processing wastewater. The flat sheet low-cost membrane used in this study was prepared by uniaxial dry pressing route, followed by sintering at 850 °C, and it possessed 39% porosity with 0.176 µm pore size. The wastewater was treated in dead-end filtration mode at different pressures varying from 0.35 to 2 bar and observed the percentage removal of COD, turbidity, and total suspended solids (TSS). Untreated wastewater had a turbidity of 150 NTU, 1200 mg/L TSS, and 10,800 mg/L COD. At a low operating pressure of 0.35 bar, 94% removal of turbidity and total suspended solids was obtained. Also, significant COD removal of 70.4% from wastewater was obtained using the prepared low-cost MF membrane. Finally, the fouling phenomenon during the wastewater treatment was analyzed and it was concluded that it followed the cake filtration model. For future work, cross-flow filtration of wastewater using fabricated Fuller's earth clay ceramic membrane is recommended as it could pave the way forward towards commercialization and wide-scale industrial applications. | Evaluation of fuller's earth clay ceramic membrane in treating raw rubber-processing wastewater | 10.1007/s42464-023-00212-8 |
2023-08-01 | Rising demands for bioenergy and green products have led researchers to explore alternative, sustainable, and cost-effective feedstocks for biorefinery, among which perennial grasses adapted to marginal lands offer cost-effective and sustainable biomass to produce bioenergy and biochemicals without creating any competition with the agricultural lands. The current study investigated the biorefinery potential of a fast-growing perennial grass Typha domingensis . Its biomass was pyrolyzed at 10, 20, 40, and 80 °C min −1 in a Thermogravimeter analyzer. The kinetics and thermodynamics features of pyrolysis were computed through Starink, Kissinger–Akahira–Sunose, and Flynn–Wall–Ozawa models. The main pyrolysis reaction occurred during the second stage at 200–380 °C at the corresponding conversions (α) of 0.2 to 0.6. The average activation energies, Gibb’s free energies, and High Heating Values ranged between 100–150 kJ mol −1 , 208–210 kJ mol −1 , and 17.699 MJ kg −1 , respectively. The lower (< 5 kJ mol −1 ) differences between the enthalpy change and activation energies at each conversion showed a thermodynamically favored reaction. The FTIR-based prominent spectral absorptions were observed at 600–800 cm −1 , bending at 1004 cm −1 , and stretching at 1644 and 3090 cm −1 which suggested the occurrence of halides and alkenes. The strong stretching bands at 1700–1725 cm −1 , and bending at 1415 cm −1 indicated the presence of carbonyl, alcoholic, and/or carboxylic functional groups. The GC–MS-based chromatogram confirmed the presence of alkanes, alcohols, organic acids, esters, ketones, aldehydes, amides, and amines. These data indicated that T. domingensis has a substantial potential to become a feedstock of a sustainable biorefinery to produce bioenergy and biochemicals. | Biorefinery potential of Typha domingensis biomass to produce bioenergy and biochemicals assessed through pyrolysis, thermogravimetry, and TG-FTIR-GCMS-based study | 10.1007/s13399-021-01892-1 |
2023-08-01 | In this study, polyvinyl butyral (PVB) was used as raw material, combined with electrospinning and microperforation process to prepare micro-/nanofiber membranes with excellent low-frequency sound absorption performance. To comprehensively explore the influence mechanisms of fiber diameter, multi-layer structure, and microperforated structure on the sound absorption performance, experiment and theoretical analysis were both conducted. Experimental results showed that appropriately reducing the fiber diameter, increasing the number of PVB membrane layers, and setting microperforated structure and cavity could improve the sound absorption performance in the low-frequency range. By adjusting the number of layers and the microperforation structure, the effective sound absorption band range of the fiber membrane can also be adjusted to better meet the sound absorption requirements. When the number of fiber layers was 20, the perforation rate was 1%, the perforation diameter was 0.6 mm, and the cavity depth was 40 mm, the PVB fiber membrane had peaks of 0.8483 and 0.9792 at 350 Hz and 480 Hz, respectively. Theoretical analysis showed that the acoustic electrical analogy model can well predict the resonance frequency and sound absorption peak of fiber membrane, and proved that microporous fiber membrane had both porous and resonant sound absorption mechanisms. These lightweight fiber membranes have great potential for application in sound absorption, such as in transportation, construction, and instrumentation. | Investigation on Low-Frequency Sound Absorption Properties of PVB Micro-/Nanofiber Membranes | 10.1007/s12221-023-00263-z |
2023-08-01 | This study presents an absorption-area-based method for the measurement of gas flow velocity using diode laser absorption spectroscopy. In the proposed method, the gas flow velocity is determined using the area difference between the absorption lines. To verify the proposed method, flow velocity measurements are conducted for test conditions with a velocity range of 5–30 m/s in a low-speed wind tunnel, and the results are compared with those of the conventional method using the Doppler-shifted peak. Oxygen in the air is selected as the target gas. By comparing the flow velocity measurement results of the conventional method and the proposed area-based method, it is confirmed that the measurement precision is improved when the proposed area-based method is used. Moreover, the measurement accuracy of the proposed area-based method is significantly improved at a relatively low-speed range of 5–10 m/s compared to the conventional method. | Area-based velocimetry using TDLAS for low-speed flow | 10.1007/s12206-023-0726-9 |
2023-08-01 | A technology for duplex plasma treatment of the steel surface is proposed. At the first stage, it is proposed to carry out nitrocarburising at the cathode polarity of the treated sample to harden the surface layer. The composition and structure of nitrocarburised layers have been studied. It is shown that as a result of the simultaneous diffusion of nitrogen and carbon, their diffusion coefficients increase, contributing to the achievement of concentrations up to 0.74 ± 0.14% and 0.67 ± 0.18%, respectively, as well as an increase in the microhardness of the surface layer to 1020 ± 20 HV. At the second stage, it is proposed to carry out anodic polishing of the nitrocarburised surface to remove the porous oxide layer with a highly developed relief, which is formed as a result of exposure to the surface of electrical discharges and high-temperature oxidation. Tribological tests have shown a joint positive effect of the hardness of the diffusion layer and low surface roughness, including a dense layer of iron oxides, on a reduction in the friction coefficient by a factor of 2 and weight wear by a factor of 23 during fatigue wear of the treated sample under boundary friction and plastic contact with the counterbody. | Improved Wear Resistance of Low Carbon Steel by Duplex Surface Treatment Combining Cathodic Plasma Electrolytic Nitrocarburising and Anodic Plasma Electrolytic Polishing | 10.1007/s12666-023-02921-5 |
2023-08-01 | This study investigates new technology for enhancing the sensitivity of low-mass dark matter detection by analyzing charge transport in a p-type germanium detector at 5.2 K. To achieve low-threshold detectors, precise calculations of the binding energies of dipole and cluster dipole states, as well as the cross sections of trapping affected by the electric field, are essential. The detector was operated in two modes: depleted at 77 K before cooling to 5.2 K and cooled directly to 5.2 K with various bias voltages. Our results indicate that the second mode produces lower binding energies and suggests different charge states under varying operating modes. Notably, our measurements of the dipole and cluster dipole state binding energies at zero fields were $$8.716\pm 0.435$$ 8.716 ± 0.435 meV and $$6.138\pm 0.308$$ 6.138 ± 0.308 meV, respectively. These findings have strong implications for the development of low-threshold detectors for detecting low-mass dark matter in the future. | Development of Low-Threshold Detectors for Low-Mass Dark Matter Searches with a p-Type Germanium Detector Operated at Cryogenic Temperature | 10.1007/s10909-023-02979-x |
2023-08-01 | Prunus mume , a woody perennial tree, is valued for its ornamental traits and has been cultivated for a long history. Low temperature is the main environmental factor restricting the distribution and affecting the growth of P. mume . In plants, some WRKY transcription factors have been reported to participate in regulating cold tolerance. However, there were few researches about functional characterization of WRKYs involving in P. mume cold response. Here, a cold-induced WRKY gene named as PmWRKY57 was cloned from a P. mume cultivar ‘Guhong Zhusha.’ PmWRKY57 protein harboring a WRKY domain and a C2H2 zinc finger motif belongs to Group IIc of WRKY family. The PmWRKY57 protein was located to the nucleus and has transcriptional activation activity. PmWRKY57 -overexpresing Arabidopsis thaliana lines showed improved cold tolerance, compared to wild-type plants. Under cold treatment, the leaves of transgenic lines contained significantly lower malondialdehyde content, and higher levels of superoxide dismutase activity, peroxidase activity, and proline content than wild-type plants. Furthermore, the expression levels of cold-response genes such as AtCOR6.6 , AtCOR47 , AtKIN1 , and AtRCI2A were up-regulated in leaves of transgenic A. thaliana compared to those in wild-type plants. This study characterized the function of PmWRKY57 in improving cold tolerance of plants. | A WRKY Transcription Factor PmWRKY57 from Prunus mume Improves Cold Tolerance in Arabidopsis thaliana | 10.1007/s12033-022-00645-3 |
2023-08-01 | Abstract— Energy-saving technologies are among the priority development lines of Russia’s power industry. In recovering the rejected heat from geothermal sources, especially those located in cold climatic zones in which there is no access to service cooling water resources, it is profitable to use organic coolants, e.g., CFC refrigerants, as working fluid for dry cooling towers. The properties of such coolants have, as a rule, been studied to a sufficient detail in the region of low temperatures, because they are mainly used as working fluids for refrigeration systems at moderate heat fluxes. To obtain data on the boiling of organic coolants on a tube bundle for taking into account the influence of bundle lower tubes on the heat transfer in the upper tubes, a vapor generator mockup with a horizontal tube bundle was developed. High-pressure water served as the heating medium; and electric heaters were provided for additionally heating the CFC refrigerant to a level close to the saturation temperature. The tube bundle includes twelve tubes arranged in three rows along the height: the central row consists of four measurement tubes, and two lateral rows consist of auxiliary tubes. Eight thermocouples are installed at the top and bottom in the slots of the central row heat-transfer tubes for measuring the surface temperature. For the lower and upper rows in the bundle, boiling heat-transfer coefficients were obtained in a wide range of specific heat fluxes. It is shown that the boiling on the upper rows is significantly more (by 30–35%) intense than it is on the lower rows. | A Study of R113 Refrigerant Boiling Processes in a Horizontal Tube Bundle under High Heat Flux Conditions | 10.1134/S0040601523080062 |
2023-08-01 | Abstract The processes accompanying the formation of a contracted (columnar) high-current nanosecond electric discharge in subcentimeter gaps filled with nitrogen are numerically investigated in this work. The space between two flat electrodes is considered in the case when a potential difference of 25 kV is instantly established between them. The voltage is applied for a time interval of 200 ns and then instantly removed. The characteristics of the nonthermal and thermal stages of electric-discharge development are studied, namely: the formation and growth of a streamer, the closure of a discharge gap by a streamer, the formation of a plasma channel, secondary ionization waves, and an increase in current density and temperature in the axial region of the channel. After switching off the electric field, the gas-dynamic processes associated with the discharge thermal effect on a neutral gas are investigated. Gas-dynamic processes are determined by the propagation of shock waves and rarefaction waves in the radial direction with respect to the axis of symmetry. The quantitative values of both the electric field (electron density and intensity) and gas-dynamic parameters (temperature, pressure, and gas velocity) are determined. | Numerical Study of Gas-Dynamic and Thermal Processes in a Pulsed Electric Discharge | 10.1134/S0015462823601055 |
2023-08-01 | An electrically heated mixer (EHM™) has been developed. It enables injecting urea-water solution in low temperature Diesel exhaust operations, such as in low-load cycles, real-driving-emissions (RDE), stop-and-go, city driving and local delivery cycles, enabling high efficiency (SCR) selective catalytic reduction of NOx in challenging operations. In low temperature exhaust, EHM frees the injected droplets from relying on the heat of the exhaust. It provides thermal energy to swiftly heat and evaporate the droplets, accelerating their thermolysis and hydrolysis reactions. Designed to be compact, low cost and robust, EHM forms plenty of reductants (ammonia, isocyanic acid) while mitigating the deposit risks. It has been tested on an engine in highly transient, low-load cycles exhibiting robust SCR of NOx well below 200 °C in long cycles with urea injection starting in as low as 130 °C. The mixer has been evaluated on a light duty Diesel engine using a purged (no-ammonia-stored) SCR catalyst simulating extended stop-and-go operations, demonstrating 99–100% NOx reduction efficiency during “stops” (idling) at 180 °C, and 80 to 95% during fast transients at 160 °C, while inhibiting deposit formation. These results were achieved without any engine or system calibration. EHM needs less than 200 W to operate on a light duty Diesel engine, and about 500 W on a heavy-duty engine. Given its thermal energy, it can be also used during cold-starts or cold-cycles for rapid-heatup of the SCR catalyst(s). EHM can also enable high engine-out NOx strategy so for fuel economy and reduced CO 2 . | A Heated AdBlue/DEF Mixer for High Efficiency NOx Reduction in Low Temperature Drive Cycles, RDE and City Driving | 10.1007/s11244-022-01714-2 |
2023-08-01 | Abstract Extended arc discharges in open-air between graphite electrodes are examined. The main goal of the study is to obtain data on changes in the parameters of electric-arc plasma during the initiation and development of a discharge. High-speed video recording of the discharge gap is used, synchronized with current and voltage oscillography data. Pyrometric measurements of the electrode temperature and spectral measurements of the discharge-plasma characteristics in the arc column and near the electrodes are carried out. | Study of the Initiation of Arc Discharges by Separating Initially Closed Electrodes | 10.1134/S001546282360092X |
2023-08-01 | Abstract The authors describe the integrated studies into the influence exerted by nonequilibrium low-temperature plasma of dielectric barrier discharge in air under normal conditions and pressure on the acid-base, adsorption and flotation properties of natural iron sulfides (pyrite and arsenopyrite). The studies aimed to correlate the plasmachemical treatment parameters with the physicochemical and process properties of sulfide minerals. Using the Hammet indicator method, it is found that plasma treatment strengthens acceptor properties and weakens electron donor properties of pyrite surface, as well as weakens acceptor properties of arsenopyrite. Adsorptive properties of pyrite relative to the electron-donor butyl xanthate grow, and, as a consequence, flotation activity of the mineral improves. In case of arsenopyrite, the adsorptive properties and flotation activity decrease. It is shown that the low-temperature plasma pretreatment of minerals reduces arsenic yield in flotation froth by 10–11% at the reduced arsenic content of concentrate by 0.71–0.78%. | The Low-Temperature Plasma Effect of Dielectric Barrier Discharge on Physicochemical and Process Properties of Natural Iron Sulfides | 10.1134/S1062739123040129 |
2023-08-01 | Two approaches based on gamma scattering technique (GST) and gamma transmission technique (GTT) have been devised and evaluated for measuring the density of polymers. The approach consists of combining Monte Carlo simulation and experimental data to determine the polymer density. The reliability of the proposed approaches is verified by experimental measurements with nine different polymers. The average relative deviation between the measured and the reference densities is under 2% for both two approaches. For the uncertainty of measured density, the GST yields better results with an average relative uncertainty of 1.61%, while this value for the GTT is 5.67%. | Combining Monte Carlo simulation and experimental data for determining the density of polymer materials in gamma scattering and gamma transmission measurements | 10.1007/s10967-023-08968-4 |
2023-08-01 | In this work, indigo carmine (IC) removal with corn cob (NCC) and KOH-treated (MCC) biomasses were studied. The removal efficiency (%R) was maximized by varying adsorbent dosages (D), initial concentrations ( C 0 ), and pHs. Therefore, D of 4 and 5 g L −1 at 50 mg L −1 of C 0 and pH 2 maximized % R for NCC (70%) and MCC (71%). The KOH-based chemical modification significantly enhanced the pore sizes and the point of zero charge. Moreover, the site’s availability also increased. Chemisorption, including adsorbate-adsorbate interaction, addressed kinetics according to the pseudo-second-order and Elovich models. The Langmuir model fit well with the isotherm data suggesting that the process is thermodynamically favored for NCC. Electrostatic interactions, hydrogen bonds, and π-related interactions mainly conducted the adsorption process. The optimum adsorption capacities showed that NCC (19.87 mg·g −1 ) was more efficient than MCC (15.59 mg·g −1 ) and several reported biomass-based adsorbents. These results suggest that corn cob biomass is a promising low-cost adsorbent to bioremediate IC. | Corn cobs and KOH-treated biomasses for indigo carmine removal: kinetics and isotherms | 10.1007/s42247-023-00526-8 |
2023-08-01 | The mechanical properties and low-cycle fatigue behavior of the hot-rolled AA2195 Al-Li alloy taken along the longitudinal direction and transverse direction were investigated. The anisotropy ductility of the alloy with the short-term natural aging (T4-SN), long-term natural aging (T4-LN), and T6 artificial aging alloy is mainly related to the grain structure and grain boundaries, whereas the weakened anisotropy of ductility is attributed to the appearance of PFZs. The T4-SN and T4-LN specimens present the cyclic hardening phenomenon due to the interaction of dislocations with dislocations or the Guinier–Preston zone. The cyclic softening phenomenon in T6 specimens is attributed to that the dislocations cut through the T 1 precipitates, and some dislocations bypass the non-shearable precipitates, which activates more potential slip systems to shear the T 1 precipitates. Graphical Abstract | Effect of Aging Precipitate on Ductility Anisotropy and Low Cycle Fatigue Behavior of AA2195 Al-Li Alloy | 10.1007/s12540-022-01365-8 |
2023-08-01 | Key message This study enriched the understanding of the mechanism of nitrogen tolerance and starvation of yellowhorn and provided a reference for the breeding of low-nitrogen tolerance germplasm in the future. Abstract Yellowhorn is a rare woody oil crop in China, which can survive in barren, drought, cold, and even saline-alkali environments. However, its growth and development can be seriously affected by low-nitrogen stress. A comprehensive understanding of its transcriptional regulation activities under low-nitrogen stress is expected to indicate the key molecular mechanisms of its tolerance to low nitrogen levels. In this study, yellowhorn was divided into control, low-nitrogen, and nitrogen-free groups for treatment. Samples were treated for 15 days before assessing physiological characteristics and transcriptome analysis. Under low-nitrogen and no-nitrogen condition, a total of 10,733 differentially expressed genes were identified, among which 3870 genes were up-regulated and 6,863 genes were down-regulated. Under low-nitrogen stress, the most up-regulated genes were enriched in the phenylpropane synthesis pathway, flavonoid synthesis pathway, and plant hormone signal transduction pathway. Our determination of total flavonoids and proanthocyanidins also verified the upregulation of these three pathways. Brassinosteroid, salicylic, and jasmonic acid (BR, SA and JA, respectively) pathway-related genes were significantly up-regulated in the signal transduction pathway of plant hormones. This study provided a comprehensive review of the transcriptomics changes of yellowhorn under low nitrogen stress and detailed its insights into the relevant mechanism of BR, SA, and JA signaling pathway in resisting low-nitrogen stress, laying a solid foundation to further identify the corresponding molecular mechanism of yellowhorn and other woody oil plants. | Transcriptomics analysis reveals Xanthoceras sorbifolia Bunge leaves’ adaptation strategy to low nitrogen | 10.1007/s00468-023-02414-4 |
2023-08-01 | A two-layer Fe–Cr–Al–Zr surface alloy has been synthesized on a zirconium substrate by magnetron sputtering and subsequent low-energy high-current electron-beam (LEHCEB) processing. The thicknesses of the top Fe 69 Cr 20 Al 11 (at.%) relatively large-grained (~1 μm) layer and the transition Fe–Zr–Cr–Al amorphous layer were about 0.7 and 0.6 μm, respectively. In turn, the amorphous layer consisted of two Fe 64–54 Zr 8–22 Cr 21–17 Al 8–7 and Fe 40–16 Zr 42–78 Cr 12–4 Al 6–2 (at.%) sublayers that differed in both zirconium and iron concentrations in wide ranges and were separated by another nanocrystalline interlayer. The Fe–Cr–Al–Zr surface alloy served as the diffusion barrier preventing the interaction of the zirconium substrate with oxygen from an environment. It was thermally stable up to ≈1173 K. | Synthesis of the Fe–Cr–Al–Zr Surface Alloy with an Amorphous Transition Layer | 10.1007/s11182-023-02955-8 |
2023-08-01 | A series of Ag/Al 2 O 3 catalysts with different Ag loading in a range of 0.5–10 wt% was synthesized by incipient wetness impregnation. The obtained catalysts were characterized by XRD, SEM-EDX, TEM and UV-Visible spectroscopy. It was shown that at low Ag loading (0.5 and 1 wt% Ag) an isolated Ag + species predominate on the alumina surface. The formation of Ag n clusters begins as Ag content was increased to 3 wt% Ag. Higher Ag loading (10 wt%) causes an agglomeration of Ag n clusters and formation of relatively large Ag nanoparticles (Ag NPs ). The catalytic performance of the Ag/Al 2 O 3 catalysts was studied in the conventional (with O 2 ) and O 3 -assisted catalytic CO oxidation (with O 3 ) and O 3 decomposition reactions within the temperature range of 25–350 °C. Analysis of the data obtained allows concluding that conventional CO oxidation proceeds mainly over Ag n clusters, while for O 3 -assited CO oxidation Ag + species are also necessary. The Ag + species promote the ozone decomposition and, as a consequence, the formation of highly reactive atomic oxygen species, which are favorable for low-temperature CO activation. The contribution of large metal species (large Ag n clusters and Ag NPs ) to the overall catalytic performance appears to be less pronounced. | Alumina-Supported Silver Catalyst for O3-Assisted Catalytic Abatement of CO: Effect of Ag Loading | 10.1007/s11244-023-01806-7 |
2023-08-01 | Abstract The structure of a low-pressure microwave discharge sustained by a standing surface electromagnetic wave (SEW) in a quartz tube filled with argon was studied. The standing wave was formed using a set of two flat metal mirrors, which formed an open SEW resonator. The plasma density profile and structure of the electromagnetic field of the SEW were studied in the pressure range from 0.25 to 10 Torr. The excitation of the standing wave allowed us to independently study the longitudinal E z and transverse E r components of the SEW electric field vector. It was confirmed experimentally that the oscillation phases of the components of the SEW are shifted by π. The excitation of the standing wave in the plasma column leads to the formation of local minimums and maximums of plasma density, whose period equals half the wavelength of the surface wave. At the same time, the spatial period of density modulation is close to the distribution of the E z component of the standing SEW. It was shown that the formation time of the modulated structure of plasma density is close to the characteristic time of diffusion, while the degree of modulation increases with increasing pressure. It was shown experimentally that it is possible to produce a plasma column with plasma density modulation n e max / n e min ≈ 5 and a length of about 10 wavelengths. | Plasma Distribution in a Column of a Low-Pressure Microwave Discharge Sustained by a Standing Surface Wave | 10.1134/S1063780X23600792 |
2023-08-01 | The effect of thickness modifications of zinc oxide (ZnO) thin films and the impressions over the electrical and optical characteristics were analyzed. ZnO thin films were deposited by the sol–gel spin coating method. For measuring the thickness of the films, a surface profilometer was operated. By maintaining an unvarying density of sol–gel (with 2% fabrication tolerance), the thin films were deposited on glass substrates. To identify the changes in optical variables, an ultraviolet–visible (UV–Vis) spectrophotometer was used. With the increment of deposition thickness, a nonlinear difference in skin depth has been observed. The bandgap showed a redshift and was in the range of 3.27–3.25 eV which is suitable for photonic applications. Electrical parameters were defined by ECOPIA Hall effect measurement system. The maximum measured sheet resistance in the current research is 5.43 × 10 7 (Ω/square) for 200 nm thin film. For 100 nm thickness, high mobility (221 cm 2 V −1 s −1 ) and small resistivity (306.3) (Ω-cm) has been obtained. The above-mentioned high mobility and small resistivity are highly desirable for the transparent electrode of CIS solar cells and buffer layer. | Thickness-Regulated Harmonious Effect on the Optical and Electrical Characteristics of ZnO Nano-Crystalline Thin Films for High Mobility Transparent Electrode | 10.1007/s42341-023-00450-y |
2023-08-01 | Targeted biomonitoring studies quantifying the concentration of zeranols in biological matrices have focused on liquid chromatography interfaced to mass spectrometry (LC–MS). The MS platform for measurement, quadrupole, time-of-flight (ToF), ion trap, etc., is often chosen based on either sensitivity or selectivity. An instrument performance comparison of the benefits and limitations using matrix-matched standards containing 6 zeranols on 4 MS instruments, 2 low-resolution (linear ion traps), and 2 high-resolution (Orbitrap and ToF) was undertaken to identify the best measurement platform for multiple biomonitoring projects characterizing the endocrine disruptive properties of zeranols. Analytical figures of merit were calculated for each analyte to compare instrument performance across platforms. The calibration curves had correlation coefficients r = 0.989 ± 0.012 for all analytes and LODs and LOQs were ranked for sensitivity: Orbitrap > LTQ > LTQXL > G1 (V mode) > G1 (W mode). The Orbitrap had the smallest measured variation (lowest %CV), while the G1 had the highest. Instrumental selectivity was calculated using full width at half maximum (FWHM) and as expected, the low-resolution instruments had the broadest spectrometric peaks, concealing coeluting peaks under the same mass window as the analyte. Multiple peaks from concomitant ions, unresolved at low resolution (within a unit mass window), were present but did not match the exact mass predicted for the analyte. For example, the high-resolution platforms were able to differentiate between a concomitant peak at 319.1915 from the analyte at 319.1551, included in low-resolution quantitative analyses demonstrating the need to consider coeluting interfering ions in biomonitoring studies. Finally, a validated method using the Orbitrap was applied to human urine samples from a pilot cohort study. | A comparison of four liquid chromatography–mass spectrometry platforms for the analysis of zeranols in urine | 10.1007/s00216-023-04791-8 |
2023-08-01 | The aim of this study was to investigate the effect of different sweeteners on the physiochemical, minerals, bioactive, and microstructure of sand pear cubes was investigated under different blanching time (0, 2.5, and 5 min). Compared with the unblanched sample, blanching led to a significant increase in the water activity, total soluble solids (TSS), and total sugars of sand pear cubes. The results regarding minerals and bioactive compounds indicated that maximum retention was observed in 2.5 min blanched samples. Meanwhile, ranking and cluster analysis showed that sweeteners had most significant effect on all the quality attributes as compared to blanching time. The low-calorie sweeteners result in low TSS and total sugars with high retention of bioactive compounds. Among these sweeteners aspartame, stevia, and sucralose indicated the same effect on physico-chemical parameters, whereas stevia-based cubes had high bioactive compounds which is also confirmed by FTIR characterization. The structural characterization revealed that the stevia-based cubes had a porous and less crystalline surface, which was responsible for the soft texture of cubes. Hence, it was observed that stevia can be a good alternative to reduce sugar in fruit cubes along with, high retention of bioactive compounds. | Functionality enhancement of osmo-dried sand pear cubes using different sweeteners: quality, bioactive, textural, molecular, and structural characterization | 10.1007/s11694-023-01894-9 |
2023-08-01 | This study reports an efficient method for growing high-quality boron nitride nanotubes (BNNTs) via chemical vapor deposition of low-melting-point precursors—magnesium diboride (MgB 2 ), magnesium nitride (Mg 3 N 2 ), and diboron trioxide (B 2 O) at a growth temperature of 1000–1300 °C. The strong oxygen-capturing ability of Mg 3 N 2 inhibits the formation of high-melting-point Mg 3 B 2 O 6 , which helps MgB 2 to maintain an efficient and stable catalytic capacity, thereby enhancing its growth efficiency and utilization of the boron source. Moreover, polydimethylsiloxane (PDMS) composites formed from these BNNTs demonstrated much greater thermal conductivities than pure PDMS. Thus, this novel strategy for preparing BNNTs is efficient, and they have great potential for application as thermal interface materials. | Growth of boron nitride nanotubes from magnesium-based catalysts | 10.1007/s12274-023-5836-2 |
2023-08-01 | Lanthanide doping is an effective strategy for modulating the emission of emitters. Herein, by changing the cluster composition to control the energy transfer pathway, the application potential of high-nuclearity lanthanide cluster (HLC) as white-light emitter has been confirmed for the first time. Specifically, by precisely controlling the proportion of Gd III , Tb III , and Eu III ions in reactants, we obtained a spherical heterotrimetallic nanocluster Gd 10 Tb 12 Eu 10 , a white-light emitter with quantum yield (QY) of 12.58% and lifetime of 327.14 µs. High-resolution electrospray ionization mass spectrometry (HRESI-MS) demonstrates that homometallic nanoclusters Ln 32 (Ln = Gd, Tb, and Eu) are tetracationic clusters and are highly stable in solution. The peripheral dense organic ligands provide a protective layer for the cluster core, which improves the stability of Ln 32 in aqueous solution, avoids the contact between metal centers and bioactive molecules, and greatly reduces the biological toxicity. In cell imaging experiments, cationic clusters Ln 32 are mainly localized on the cell membrane with negative charge distribution. As far as we know, this is the first time that spherical lanthanide nanoclusters have been used for membrane imaging of living cell, opening the door for the application of HLCs in biological imaging. | Spherical lanthanide nanoclusters toward white-light emission and cell membrane imaging | 10.1007/s12274-023-5867-8 |
2023-08-01 | Resistance spot welding was used to join AISI 316L stainless steel to DIN 33MnCrB5-2 low alloy steel using Ni powder interlayer and foil of ERNiCr-3 filler wire. Optical microscopy and SEM with EDS attachment analysis were used to study the microstructure. The mechanical properties of the joints were evaluated by tensile shear and microhardness tests. The results indicated that high current and/or time negatively affected the weld shear strength due to crack formation and utilizing Ni powder and ERNiCr-3 foil produced crack-free welds. The Nugget zone in the as-welded joint was characterized by austenite and ferrite with dendritic growth type. Ni powder interlayer encouraged the primary austenitic solidification type with an equiaxed growth mode. While the ERNiCr-3 foil produced a microstructure of mostly primary austenitic with cellular growth mode. Also, Ni powder reduced the hardness in the nugget zone to half. | Characterization of AISI 316L Stainless Steel/Low Alloy Steel Resistance Spot Dissimilar Weld | 10.1007/s13632-023-00990-y |
2023-08-01 | Abstract In order to study the corrosion dynamics of low carbon steel in neutral salt spray environment, the low carbon steel samples were carried out neutral salt spray corrosion test (SST). The corrosive behavior of low carbon steel was examined by scan electron microscopy, electrochemical impedance spectra, and potentiodynamic polarization, and the salt spray corrosion dynamics laws of low carbon steel were discussed. SST results showed that as the corrosion progresses, the rust layers will become dense, forming a “scab” structure, and forming an occluded corrosion zone with the substrate, resulting in increased corrosion rate. The newly generated inner rust layers were loose and expanded outward, caused the “scab” structure to peel off, and this has a certain periodicity. After corrosion, the surface of the substrate is pit-shaped, which uniformity is poor. Electrochemical tests showed that the corrosion process of low carbon steel in salt spray environment was mainly controlled by cathode diffusion, and the corrosion rate was relatively stable. | Corrosion Dynamics of Low Carbon Steel in Salt Spray Environment | 10.1134/S2070205123700636 |
2023-08-01 | Abstract Complex interpretation of the distribution of δ 13 C and δ 18 О values in carbonates, as well as δ 34 S and 87 Sr/ 86 Sr values, in gypsum from the lower Eifelian Osveya horizon (Belarus) showed that significance of the diagenetic isotope signals is low and the isotope variations can be explained consistently within a sedimentation model. Along with the section intervals with standard marine δ 13 C values, there are negative excursions of the parameter (up to –7…–11‰) marking segments with carbonate–sulfate rocks and smaller sulfate manifestations. The excursions correspond to evaporitic episodes when the basin became shallower and, probably, disintegrated into separate depressions, leading to increase in the role of continental water enriched with soil carbon in the geochemical sedimentation system due to the continental runoff activation and/or shallowing. The waters could enter both from the prolonged exposed land areas where the Eifelian rocks are absent until now and from the periodically existing islands. The oxygen isotope composition does not respond to negative δ 13 C excursions by similar shifts due to the possible absence of significant difference between the δ 18 О values of the atmospheric precipitation generating the land water and the seawater at low latitudes where the Belarus region was situated in the Devonian. In 40% of the studied samples, the δ 18 О values range from –4 to –2‰, corresponding to the Eifelian “plateau” (approximately –3‰) in the generalized chemostratigraphic curve based on calcite of brachiopod shells from several regions of the world. The δ 18 О values higher than –2‰ (44% of samples), probably, are related to water evaporation, whereas values lower than –2‰ (16% of samples), which can decrease to –7.0…–9.5‰ at the peaks of evaporation episodes, are caused by the water heating (sometimes very significant) during the basin shallowing. Activation of the role of continental water accompanying the evaporation episodes is supported by the following fact: the 87 Sr/ 86 Sr ratio in the Osveya gypsum (0.708402–0.708742) is much higher than in the Eifelian seawater according to a global estimate (0.70772), whereas the δ 34 S value in gypsum (15.5–21.2‰) in more than one-half of the analyzed samples is lower than typical values in the Middle Devonian seawater sulfate (19–20‰). | С, О, S, and Sr Isotopes in Rocks of the Lower Eifelian Osveya Horizon in Belarus | 10.1134/S0024490223700165 |
2023-08-01 | Exposure to greenness is increasingly linked to beneficial health outcomes, but the associations between greenness and the disease burden of lower respiratory infections (LRIs) are unclear. We used the normalized difference vegetation index (NDVI) and the leaf area index (LAI) to measure greenness and incidence, death, and disability-adjusted life years (DALYs) due to LRIs to represent the disease burden of LRIs. We applied a generalized linear mixed model to evaluate the association between greenness and LRI disease burden and performed a stratified analysis, after adjusting for covariates. Additionally, we assessed the potential mediating effects of fine particulate matter (PM 2.5 ), ozone (O 3 ), nitrogen dioxide (NO 2 ), and heat on the association between greenness and the disease burden of LRIs. In the adjusted model, one 0.1 unit increase of NDVI and 0.5 increase in LAI were significantly inversely associated with incidence, death, and DALYs due to LRIs, respectively. Greenness was negatively correlated with the disease burden of LRIs across 15–65 age group, both sexes, and low SDI groups. PM 2.5 , O 3 , and heat mediated the effects of greenness on the disease burden of LRIs. Greenness was significantly negatively associated with the disease burden of LRIs, possibly by reducing exposure to air pollution and heat. | Association of greenness with the disease burden of lower respiratory infections and mediation effects of air pollution and heat: a global ecological study | 10.1007/s11356-023-28816-y |
2023-08-01 | In this work, the directional excitation of acoustic graphene plasmons (AGPs) are numerically studied using finite element methods. In our proposed hybrid graphene-metal structure under oblique incidences, not only are AGPs excited efficiently, but also they are unidirectional propagating along a graphene monolayer. Although the symmetry AGPs dispersion relations are broken by oblique incidence, both left- and right-moved AGPs are excited simultaneously at a resonant wavelength due to almost equaled wavenumbers of directional propagated AGPs. Based on the fact that great AGPs excitation efficiency can’t guarantee high EM energy propagating in one direction, we will focus on how the directional propagating net energy are affected by geometrical parameters. Due to the tunable graphene conductivity, AGPs propagation with great unidirectional net energy can be dynamically controlled by a relatively low externally applied bias voltage (electrostatic gating). The prototype structure may find applications in ultra-confined plasmon launchers and switchers in integrated optics. | Directional Excitation of Acoustic Graphene Plasmons Using Oblique Incidences | 10.1007/s11468-023-01860-7 |
2023-08-01 | Cosmic Ray Laboratory – TIFR, Ooty, India is operating the largest tracking muon telescope as a component of the GRAPES-3 (Gamma Ray Astronomy PeV EnergieS at phase – 3) experiment. The basic building blocks of the telescope are proportional counters (PRCs), a large number of which are fabricated in-house for the planned expansion of the existing muon telescope to double its area and enhance the solid angle coverage from 2.3 sr to 3.7 sr as well as achieving higher sensitivity for studying space weather and atmospheric phenomena, cosmic ray composition, etc. The existing muon telescope consists of 3712 PRCs, and after the planned expansion which requires an additional 3776 PRCs, the area of the telescope will increase from the present 560 m $$^{2}$$ 2 to 1130 m $$^{2}$$ 2 . Each of the PRCs will need to be individually equipped with front-end electronics for processing the output signals. The output pulses from PRCs are extremely feeble, and their charges are in the order of $$\sim $$ ∼ 100 pC. The tiny signal has to be isolated from potential sources of noise before its processing. High-performance, ultra-low noise, and cost-effective electronics are designed, developed, and mass-produced in-house for about 8000 channels of PRCs. The quality of data is improved significantly by interfacing the new electronics with PRCs of the existing muon telescope due to improved signal-to-noise (S/N) ratio, and the data acquisition is made effective as a result of multifold improvement achieved by avoiding undesired interruptions in the data. | High-Performance and Low-Noise Front-End Electronics for GRAPES-3 Muon Telescope | 10.1007/s10686-023-09898-5 |
2023-08-01 | We have previously shown that histone deacetylase (HDAC) inhibition and cranial radiotherapy (RT) independently improve molecular and behavioral Alzheimer’s disease (AD)-like phenotypes. In the present study, we investigate the synergistic potential of using both RT and HDACi as a low-dose combination therapy (LDCT) to maximize disease modification (reduce neuroinflammation and amyloidogenic APP processing, increase neurotrophic gene expression) while minimizing the potential for treatment-associated side effects. LDCT consisted of daily administration of the HDAC3 inhibitor RGFP966 and/or bi-weekly cranial x-irradiation. Amyloid-beta precursor protein (APP) processing and innate immune response to LDCT were assessed in vitro and in vivo using human and murine cell models and 3xTg-AD mice. After 2 months of LDCT in mice, behavioral analyses as well as expression and modification of key AD-related targets (Aβ, tau, Csf1r, Bdnf, etc.) were assessed in the hippocampus (HIP) and prefrontal cortex (PFC). LDCT induced a tolerant, anti-inflammatory innate immune response in microglia and increased non-amyloidogenic APP processing in vitro. Both RT and LDCT improved the rate of learning and spatial memory in the Barnes maze test. LDCT induced a unique anti-AD HIP gene expression profile that included upregulation of neurotrophic genes and downregulation of inflammation-related genes. RT lowered HIP Aβ 42/40 ratio and Bace1 protein, while LDCT lowered PFC p-tau181 and HIP Bace1 levels. Our study supports the rationale for combining complementary therapeutic approaches at low doses to target multifactorial AD pathology synergistically. Namely, LDCT with RGFP966 and cranial RT shows disease-modifying potential against a wide range of AD-related hallmarks. | Investigating the Synergistic Potential of Low-Dose HDAC3 Inhibition and Radiotherapy in Alzheimer’s Disease Models | 10.1007/s12035-023-03373-0 |
2023-08-01 | Abstract Glassy chalcogenides A V B VI obtained by solidification of high-temperature melts inherit the polymolecular nature of the melt. The influence of this circumstance on the optical properties of glasses is important for the fabrication of optical fibers and has not been adequately studied. Bulk samples of high-purity As 40 – x S 60 + x glasses (0 < x < 5) containing less than (1–2) × 10 –5 wt % metal and silicon impurities and not more than (0.5–1) × 10 –4 wt % carbon, oxygen, and hydrogen compounds were manufactured, and optical fibers were fabricated from these materials. The IR spectra of 12 cm-long bulk samples and optical fibers of up to 15 m length were recorded in the 1000–2000 cm –1 spectral range. The spectra of the bulk samples and the optical fibers showed absorption bands with maxima at 1950, 1805, 1460, and 1320 cm –1 , due to the presence of super-stoichiometric amount of sulfur in the glass. The corresponding extinction coefficients were determined. The results of the study indicate that the stoichiometry of As 2 S 3 can be considered as a factor significantly affecting the optical characteristics of glass. | Effect of the Stoichiometry of As2S3 on the Optical Transmission of Glass in the 5–8 µm Spectral Range | 10.1134/S0012500823600578 |
2023-08-01 | The need for precise orbit determination (POD) has grown significantly due to the increased amount of space-based activities taking place at an accelerating pace. Accurate POD positively contributes to achieving the requirements of Low-Earth Orbit (LEO) satellite missions, including improved tracking, reliability and continuity. This research aims to systematically analyze the LEO–POD in four aspects: (i) data sources used; (ii) POD technique implemented; (iii) validation method applied; (iv) accuracy level obtained. We also present the most used GNSS systems, satellite missions, processing procedures and ephemeris. The review includes studies on LEO–POD algorithms/methods and software published in the last two decades (2000–2021). To this end, 137 primary studies relevant to achieving the objective of this research were identified. After the investigation of these primary studies, it was found that several types of POD techniques have been employed in the POD of LEO satellites, with a clear trend observed for techniques using reduced-dynamic model, least-squares solvers, dual-frequency signals with undifferenced phase and code observations in post-processing mode. This review provides an understanding of the various POD techniques, dataset utilized, validation techniques, and accuracy level of LEO satellites, which have interest to developers of small satellites, new researchers and practitioners. | Precise orbit determination of LEO satellites: a systematic review | 10.1007/s10291-023-01520-7 |
2023-08-01 | Electric vehicle (EV) on-board chargers (OBC) use high-frequency transformers for isolation between the grid power and the propulsion battery. Additionally, low voltage dc-to-dc converters (LDC) require high-frequency transformers for high step-down and electrical isolation. Although a high-frequency transformer is used for isolation, it is desirable to minimize the use of magnetic materials because the isolation breakdown between the windings of the transformer occurs due to vibration. It also increases the weight and volume, and reduces the mileage of vehicles. Therefore, this paper proposes an OBC–LDC integrated system without additional windings by dividing the transformer windings used for the OBC. Depending on the connection state of the selective switch in the proposed system, it is divided into a propulsion battery charging mode and an auxiliary battery charging mode. At the same time, the selective switch converts the required transformer turns ratio in the changed operation mode. The proposed OBC–LDC integrated system is verified through prototype experiments. In addition, the volume and weight of a conventional vehicle charger and the proposed integrated charger are compared, and the economic benefits of the proposed charger are derived through cost model analysis (CMA). | Power conversion system integrating OBC and LDC using tapped transformers for weight, volume, and cost reductions in electric vehicles | 10.1007/s43236-023-00654-8 |
2023-08-01 | Abstract We have studied the geological structure, material composition of the ores, and the age of the Nizhny Birkachan volcanogenic gold–silver deposit discovered recently. The ore bodies consist of veins and vein-streak zones of adularia-carbonate-quartz composition; they lie in granodiorite porphyries with U‒Pb zircon age (ID-TIMS) equal to 335 ± 2 Ma. The ores are low sulfide, low silver (Au/Ag = 1–2), with pyrite dominating the ore minerals. The Ag minerals are tennantite, Ag sulfide, native gold and silver, and hessite. From an ore vein we obtained an adularia-based 40 Ar/ 39 Ar age equal to 169 ± 4 Ma, which reflects the rejuvenation of the isotopic argon system after the emplacement of a dike of unaltered Jurassic basites that cuts through the ore body. The Nizhny Birkachan deposit has a geological structure and ore composition that are very similar to those of other Au-Ag deposits at the Kedon volcano-plutonic belt such as Kubaka and Birkachan; it was also formed in the age span 290–335 Ma. | The Nizhny Birkachan Gold-Silver Epithermal Deposit, Omolon Massif, Northeast Russia: Geological Structure, Ore Mineralogy, and Age | 10.1134/S0742046323700240 |
2023-08-01 | Background The hypothalamic–pituitary–adrenal (HPA) axis is a neuroendocrine system involved in controlling stress responses in humans under physiological and pathological conditions; cortisol is the main hormone produced by the HPA axis. It is known that calorie restriction acts as a stressor and can lead to an increase in cortisol production. Renin–angiotensin–aldosterone system (RAAS) is a complex endocrine network regulating blood pressure and hydrosaline metabolism, whose final hormonal effector is aldosterone. RAAS activation is linked to cardiometabolic diseases, such as heart failure and obesity. Obesity has become a leading worldwide pandemic, associated with serious health outcomes. Calorie restriction represents a pivotal strategy to tackle obesity. On the other hand, it is well known that an increased activity of the HPA may favour visceral adipose tissue expansion, which may jeopardize a successful diet-induced weight loss. Very low-calorie ketogenic diet (VLCKD) is a normoprotein diet with a drastic reduction of the carbohydrate content and total calorie intake. Thanks to its sustained protein content, VLCKD is extremely effective to reduce adipose tissue while preserving lean body mass and resting metabolic rate. Purpose The purpose of this narrative review is to gain more insights on the effects of VLCKD on the HPA axis and RAAS, in different phases of weight loss and in different clinical settings. | Effects of very low-calorie ketogenic diet on hypothalamic–pituitary–adrenal axis and renin–angiotensin–aldosterone system | 10.1007/s40618-023-02068-6 |
2023-08-01 | The COVID-19 pandemic triggered unprecedented scientific efforts worldwide and launched several initiatives to promote international cooperation. Because international scientific collaborations between high-income countries (HICs) and low- and middle-income countries (LMICs) are not always balanced, analyzing research leadership helps to understand the global dynamics of knowledge production during COVID-19. In this study, we focused on HIC–LMIC collaborations on COVID-19 research in 469,937 scientific publications during the first 2 years of the pandemic (2020–2021). Co-authorship and authors’ affiliation were used to identify international collaborations, according to country income level. The leadership analysis considered the countries of the first and last authors of publications. The results show that (i) most publications with international collaborations (49.3%) involved researchers from HICs and LMICs; (ii) collaborative research between HICs and LMICs addressed relevant public health needs; (iii) HIC–LMIC collaborations were primarily led by researchers from the United States, China, the United Kingdom, and India; (iv) most HIC–LMIC publications (44%) had shared leadership, with research interests linked to national expertise and global interests. This study contributes to the analysis of research collaborations on COVID-19 and sheds light on North–South relations in the production and dissemination of scientific knowledge. | Leadership and international collaboration on COVID-19 research: reducing the North–South divide? | 10.1007/s11192-023-04754-x |
2023-08-01 | As a repository of REE, the Paleoproterozoic phosphorite of the Aravalli Basin in India is explored time to time. Paleoproterozoic phosphorite deposits of the Sallopat sub-basin Banswara district of the Aravalli Supergroup show moderate REE concentrations much lower than that of average marine phosphorites. Different ratios and PAAS-normalized REE distribution patterns reflect MREE enrichment over LREE and HREE in these phosphorites. MREE enrichment confirmed by (Sm/Yb) N versus (Sm/Pr) N relationship and attributed to the selective uptake by cyanobacteria and mixing of riverine inputs. Y/Ho, La/Ce and Er/Nd ratios confirm that the REE in Sallopat phosphorites might have been affected by the argillaceous terrigenous and plagioclase-rich sediments probably derived from Banded Gneissic Complex. Diagenetic modeling indicates that REE were concentrated during early diagenetic processes with limited weathering influence. Moderate negative to low Ce anomaly depicts oxic to sub-oxic conditions of seawater due to oxidation of Ce 3+ to Ce 4+ whereas Eu 3+ reduced to Eu 2+ indicating positive Eu-anomaly and reducing conditions as well during the deposition. These anomalies may be due to the stratified restricted marine environment of upwelling and mingling of organic-rich anoxic deep water with oxic upper seawater prior to the formation of phosphorite deposits in the embayment. Enrichment of REE in Sallopat phosphorite relies on various physico-chemical conditions. These phosphorites may have been formed in restricted marine water which was influenced by extra clastic sediment input carried out by fluvial systems. | Rare earth element signatures of Paleoproterozoic Sallopat phosphorites of Aravalli Basin, India: implications for diagenetic effects and depositional environment | 10.1007/s11631-023-00612-y |
2023-08-01 | Abstract Some unmanned aerial vehicles, micro-air vehicles, and small-scale wind turbines operate at Reynolds number values less than $$5 \times 10^5$$ 5 × 10 5 based on chord length. However, there are limited data sets characterizing the airfoil performance at Reynolds number spanning $$2\times 10^4 \le Re_c \le 5\times 10^4$$ 2 × 10 4 ≤ R e c ≤ 5 × 10 4 . The objective of this study is to investigate the impact of airfoil thickness and camber for canonical NACA airfoils at Reynolds numbers in this range and to correlate the observed aerodynamic behavior with the flow patterns. For this purpose, NACA-0009, 0012, 0021, and 6409 airfoils were used, and all experiments were performed in a water tunnel. A high-precision load cell was utilized to characterize the performance of the airfoils, and the hydrogen bubble flow visualization was used to assess the flow over the airfoils. The results showed that the airfoil thickness and camber significantly influence the aerodynamic performance and a strong dependence on the Reynolds number was observed. Symmetric NACA airfoils exhibited nonlinear lift behavior at Reynolds number below $$4\times 10^4$$ 4 × 10 4 as well as abrupt changes in lift values. The cambered airfoil showed some Reynolds number dependence but performed better than its symmetrical counterpart. The aerodynamic performance was correlated with the observed flow features around the airfoils. Graphical abstract | Aerodynamic behavior and flow visualization on canonical NACA airfoils at low Reynolds number | 10.1007/s12650-023-00910-w |
2023-08-01 | The hypothesis about the hormetic effect of low-dose gamma applications (0, 10, 20, 30, 40 Gy- 60 Co) on common bean ( Phaseolus vulgaris L.) cultivars (F16 and Öz Ayşe) grown under different drought stress conditions (−0.20 and −0.40 MPa) was evaluated by determining the proteinogenic amino acid profiles and morphological changes in the seedlings. 20 Gy for Öz Ayşe and 10 Gy for F16 reversed the negative effects of drought and improved vegetative growth at −0.40 MPa drought intensity. The fact that the interactions of the cultivar, drought, and gamma dose had a statistically significant effect ( p < 0.01) on the change in the amino acid profile was evaluated to be associated with the accumulation of the amino acids that serve as an energy and carbon source as well as the cell growth, and preservation of cell pH value in plants. Although the highest amount of amino acids was detected in F16 at 30 Gy, when evaluated with the vegetative data, it was concluded that the suppression determined in plant development was related to protein degradation. The absence of germination at 40 Gy supports this result. The results revealed that the hormetic effect varies according to the genotype, and depending on the severity of the stress, the plants responded with a decrease or increase in the amount of amino acids. These results strengthen the hypothesis that the accumulation of amino acids under drought conditions has a positive effect on the plant’s ability to cope with stress. | Hormetic Response of Low Dose Gamma on Phaseolus Vulgaris L. Under Drought Stress: Proteinogenic Amino Acids Profile | 10.1007/s10343-022-00769-1 |
2023-08-01 | Abstract The tolerance range of water salinity reaches 0.09–9.3 and 0.008–6.0 g/L for the larvae of Chironomus balatonicus Devai, Wülker et Scholl, 1983 and Ch. plumosus L., 1758, respectively. In the tolerance range of salinity of the medium, the sodium, potassium, calcium, and magnesium concentrations in the body of Ch. balatonicus are within 33.9–77.1, 7.7–13.7, 11.9–37.6, and 54.7–110.6 mmol/kg wet weight, respectively. In larvae of Ch. plumosus (developmental stage III), the concentrations of sodium, potassium, calcium, and magnesium are within 62.7–80.8, 10.6–18, 6.7–12, 2.9–6.0 mmol/kg wet weight, and in larvae of Ch. plumosus (developmental stage IV)–49.6–62.3, 9.7–14.8, 42.5–62.2, 47.9–83.4 respectively. In the optimal salinity range of 0.8–5.3 g/L, the sodium concentration in the body of Ch. balatonicus is maintained at a constant level, decreases in the critically low zone of 0.8–0.09 g/L, and increases in the critically high zone of 5.3–9.3 g/L. In critically low and high salinity zones, the organism’s ability to survive is reduced. The content of sodium in the body of freshwater aquatic organisms serves as a reliable criterion for assessing optimal, critically low, and critically high salinity zones. | Content of Sodium, Potassium, Calcium, and Magnesium in the Body of Larvae of Sibling Species Chironomus balatonicus and Chironomus plumosus Depending on the Salinity of the Medium | 10.1134/S1995082923040120 |
2023-08-01 | Computer tomography (CT) has played an essential role in the field of medical diagnosis. Considering the potential risk of exposing patients to X-ray radiations, low-dose CT (LDCT) images have been widely applied in the medical imaging field. Since reducing the radiation dose may result in increased noise and artifacts, methods that can eliminate the noise and artifacts in the LDCT image have drawn increasing attentions and produced impressive results over the past decades. However, recent proposed methods mostly suffer from noise remaining, over-smoothing structures, or false lesions derived from noise. To tackle these issues, we propose a novel degradation adaption local-to-global transformer (DALG-Transformer) for restoring the LDCT image. Specifically, the DALG-Transformer is built on self-attention modules which excel at modeling long-range information between image patch sequences. Meanwhile, an unsupervised degradation representation learning scheme is first developed in medical image processing to learn abstract degradation representations of the LDCT images, which can distinguish various degradations in the representation space rather than the pixel space. Then, we introduce a degradation-aware modulated convolution and gated mechanism into the building modules (i.e., multi-head attention and feed-forward network) of each Transformer block, which can bring in the complementary strength of convolution operation to emphasize on the spatially local context. The experimental results show that the DALG-Transformer can provide superior performance in noise removal, structure preservation, and false lesions elimination compared with five existing representative deep networks. The proposed networks may be readily applied to other image processing tasks including image reconstruction, image deblurring, and image super-resolution. | Degradation Adaption Local-to-Global Transformer for Low-Dose CT Image Denoising | 10.1007/s10278-023-00831-y |
2023-08-01 | Abstract It is possible to use low-potential wind energy for the efficient operation of a wind power plant and for increasing the Annual Energy Production for guaranteed power supply to facilities in remote rural areas with a shortage of wind power. Currently in the development of large wind power plants worldwide hydraulic transmission is used to increase reliability and reduce the cost. However, the efficiency of such systems is lower than the efficiency of systems with a mechanical transmission (gearbox). But in regions with a shortage of wind power, wind power plants with a gearbox are not effective, and a hydraulic transmission could provide an increase in the Annual Energy Production of small wind power plants. Proposed is a small multi-unit wind-driven power plant with a hydraulic drive and an accumulator for power supply to remote facilities in rural areas. Methods for calculating the parameters and modes of operation of a multi-unit wind-driven power plant have been developed. The operation of a multi-unit wind-driven power plant was studied in the range of wind speeds of 4–14 m/s. The results of the theoretical analysis of the operation of the multi-unit wind-driven power plant are presented in the form of torque, rotational speed, power and flow rate diagrams. The results showed that the sum of flow rates of several pumps in the hydraulic system can provide the required constant flow rate of the hydraulic motor in a wide range of wind speeds. Thus, even at low wind speeds of 3–4 m/s on a typical day for a region with an average periodic wind speed of 4.3 m/s the total daily flow shortage is 75.2 L/min, while the total daily surplus is 180 L/min. The above calculation methods allow for a comparative analysis of the parameters, as well as the selection of design for the multi-unit wind-driven power plant being developed. The use of a hydraulic system with a hydraulic accumulator and several wind-receiving devices of different parameters, connected in parallel, significantly increases the efficiency of a small wind-driven power plant in a region with low-potential wind energy. In this case, the efficiency of the electric generator of a wind-driven power plant will always be maximum, since a constant rotational speed of the generator shaft is maintained and optimal generator modes are provided. | Theoretical Analysis of the Operation of a Multi-Unit Wind Power Plant in Conditions of a Shortage of Wind Power | 10.3103/S0003701X22601004 |
2023-08-01 | Purpose of Review Small renal stones in the lower pole are often difficult to treat. The angle of the lower pole to the renal pelvis (lower pole angle) is a limiting factor to rendering the patient stone free. This review explores the definitions of the lower pole angle, the various treatment options available, and how outcomes are influenced by the angle. Recent Findings It is clear the lower pole angle definition varies widely depending on described technique and imaging modality. However, it is clear that outcomes are worse with a steeper angle, especially for shock wave lithotripsy and retrograde intrarenal surgery (RIRS). Percutaneous nephrolithotomy has similar reported outcomes to RIRS, and there is limited evidence it may be superior for steeper angles over RIRS. Summary Lower pole stones can be technically challenging and adequate assessment prior to choosing operative approach is key. | Endourological Options for Small (< 2 cm) Lower Pole Stones — Does the Lower Pole Angle Matter? | 10.1007/s11934-023-01161-w |
2023-08-01 | Key message Whereas Shumard oak seedlings are intolerant of dormant season flood, Nuttall oak seedlings are tolerant. Flooding more than 1–2 months beyond budbreak may have persistent negative impacts on Nuttall oaks. Abstract Since flooding in winter and spring is an integral part of bottomland hardwood ecosystems in the southeastern United States, moderately flood-tolerant oaks, like Nuttall oak ( Quercus texana ), should be well adapted to flooding during these seasons. To quantify the potential for injury from different lengths of winter flooding, we flooded seedlings of Nuttall oak and moderately flood intolerant Shumard oak ( Q. shumardii ) for 0, 1, 2, and 3 months, with the first month of flooding occurring during the dormant season. Flooding during dormancy had no effect on Nuttall oak, but Shumard oak seedlings had reduced growth in the spring. Flooding that extended beyond budbreak resulted in reduced leaf area and root biomass accumulation in spring for both species, while Shumard oaks also experienced high mortality. At the end of the growing season, Nuttall oaks that had been flooded accumulated tissue biomasses similar to non-flooded seedlings, except taproot biomass, which was reduced 40% by 3 months of flooding. It appears that Nuttall oak delayed fully investing in spring growth until after flooding subsided, and then was largely able to compensate following flooding that extended one month beyond budbreak. However, flooded Shumard oaks did not show similar signs of recovery. Thus, sites that flood at any time of year would not be suitable for Shumard oak. Our results suggest that natural or human-imposed flooding can extend several weeks beyond budbreak without harming Nuttall oaks, but inundation prolonged several months beyond budbreak could weaken the ability to respond to subsequent stresses. | Resiliency of Nuttall oak but not Shumard oak to winter and spring flood: dormancy alone does not confer flood tolerance | 10.1007/s00468-023-02411-7 |
2023-07-31 | The potential of microfluidics for point-of-care diagnosis and personalized medicine has been drawing attention to this technology in biomedical fields. Low Temperature Co-Fired Ceramics (LTCC) is a promising material for the construction of microfluidic systems for point-of-care use since it has favorable inherent physico-chemical properties, and its fabrication methods are simple and easy to adapt to further needs. Here, we design and construct a microdevice for the continuous synthesis of gold nanoparticles (AuNPs), based on reduction using modified citrate protocols. The AuNPs produced were characterized using Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), and Zeta Potential analysis. Depending on the temperature, residence time, and citrate concentration chosen during synthesis, a range of nanoparticle sizes and shapes were consistently produced, indicating that the process could be suitable for the production of nanoparticles for personalized medicine. By using a single microreactor, AuNPs were produced with sizes ranging from 19 to 117 nm, with at least 7 different shapes, including complex morphologies, such as nanodendrites and tadpole-shaped particles, indicating the simplicity and versatility of the microfluidic device. Graphical abstract | Synthesis of gold nanoparticles with different sizes and morphologies using a single LTCC-based microfluidic system for point-of-care use in personalized medicine | 10.1007/s10404-023-02667-y |
2023-07-31 | The use of polyvinyl chloride (PVC) plastic bags leads to environmental pollution and waste residues caused by low recycling and slow degradation rates, which is inconsistent with the international mainstream concept of green development. One of the promising approaches is integrating plastic waste with abundant woody residue in producing value-added composite using novel renewable technology with low energy consumption. Unfortunately, this approach currently has drawbacks, particularly with the resulting composite showing low mechanical properties that in turn limit its applications. Here, we upcycle PVC plastic waste via combined utilization of the PVC debris and wood fibers using a low-energy approach involving one-step cell collapse and chemical bonding, producing a high-performance poplar-PVC composite. Through various tests and characterization, the composite possesses excellent tensile strength (255.71 MPa) and flexural strength (105.39 MPa), high water resistance (water absorption is only 4.87%), and heat and ultraviolet (UV) resistance. The combination of natural wood fibers and PVC debris is a promising new circular economy product from the increasing global amounts of PVC waste is important to meet global goals. In view of the above advantages, poplar-PVC composite has the potential to be a viable candidate material on the road to sustainable development. | Sustainable upcycling of plastic waste and wood fibers into high-performance laminated wood-polymer composite via one-step cell collapse and chemical bonding approach | 10.1007/s42114-023-00723-3 |
2023-07-31 | Background The role of pro-resolving mediators in inflammation is a new concern in research. The effect of low-dose aspirin on production of a special kind of these mediators named aspirin triggered lipoxin (ATL) has been studied on different tissues. This randomized clinical trial evaluated the effect of low-dose aspirin on ATL and pro-inflammatory mediators’ level in periapical fluid of necrotic teeth with large lesions. Methods Twenty-four patients with necrotic pulp and periapical lesion were randomly assigned to low-dose aspirin and placebo groups. In the first appointment, canals were shaped up to F3 size and #40 K-file and cleaned with 10 milliliters 2.5% sodium hypochlorite and 17% Ethylenediaminetetraacetic acid. Periapical fluid was sampled by a paper cone. The tooth was temporized without any intracanal medication. Tablets were administered for 7 days, then the teeth were re-opened and the sampling were repeated. Interleukin-1 beta (IL-1β), prostaglandin E2 (PGE2) and ATL were analyzed by enzyme-linked immunosorbent assay. Data were analyzed with paired t-test using SPSS statistical software, version 21 (α = 0.05). Results A significant reduction in PGE2 and IL-1β was noted in the aspirin-treated group while an increase in ATL was observed (P < 0.001). There was no significant difference in the mediator scores before and after in the placebo-treated group (P > 0.05). Conclusion Low-dose aspirin can influence the inflammatory process by reducing pro-inflammatory mediators such as PGE2 and IL-1β, as well as increasing the pro-resolving mediators such as ATL. Trial registration IRCT20191211045702N1. | The effect of low-dose aspirin on aspirin triggered lipoxin, interleukin 1 beta, and prostaglandin E2 levels in periapical fluid: a double-blind randomized clinical trial | 10.1186/s12903-023-03243-0 |
2023-07-29 | The results of viscosity measurements at moderate densities on the two gaseous mixtures carbon dioxide–nitrogen and ethane–methane including the pure gases between 253.15 K and 473.15 K, originally performed by Humberg et al. at Ruhr University Bochum, Germany, using a rotating-cylinder viscometer between 0.1 MPa and 2.0 MPa, were employed to determine the interaction viscosity, $$\eta _{12}^{(0)}$$ η 12 ( 0 ) , and the product of molar density and diffusion coefficient, $$(\rho D_{12})^{(0)}$$ ( ρ D 12 ) ( 0 ) , each in the limit of zero density. The isothermal viscosity data were evaluated by those authors with density series restricted to the second order at most to derive the zero-density viscosities and initial density viscosity coefficients, $$\eta _\textrm{mix}^{(0)}$$ η mix ( 0 ) and $$\eta _\textrm{mix}^{(1)}$$ η mix ( 1 ) , for the mixtures, as well as, $$\eta _i^{(0)}$$ η i ( 0 ) and $$\eta _i^{(1)}$$ η i ( 1 ) ( $$i=1,2$$ i = 1 , 2 ), respectively, for the pure gases. Humberg et al. have already compared their $$\eta _\textrm{mix}^{(0)}$$ η mix ( 0 ) and $$\eta _i^{(0)}$$ η i ( 0 ) data for carbon dioxide–nitrogen and ethane–methane with corresponding viscosity values theoretically computed for the nonspherical potentials of the intermolecular interaction. Now we employed $$\eta _\textrm{mix}^{(0)}$$ η mix ( 0 ) and $$\eta _\textrm{mix}^{(1)}$$ η mix ( 1 ) as well as $$\eta _i^{(0)}$$ η i ( 0 ) and $$\eta _i^{(1)}$$ η i ( 1 ) in two procedures to derive $$\eta _{12}^{(0)}$$ η 12 ( 0 ) values. For this, we needed $$A_{12}^*$$ A 12 ∗ values (ratio between effective cross-sections of viscosity and diffusion). But the second procedure applying the initial density viscosity coefficients $$\eta _\textrm{mix}^{(1)}$$ η mix ( 1 ) and $$\eta _i^{(1)}$$ η i ( 1 ) failed to yield reasonable $$\eta _{12}^{(0)}$$ η 12 ( 0 ) values. The first procedure should provide the best results when it is possible to use $$A_{12}^*$$ A 12 ∗ values computed for the nonspherical potential. The effect is comparatively small if $$\eta _{12}^{(0)}$$ η 12 ( 0 ) is determined. But if $$(\rho D_{12})^{(0)}$$ ( ρ D 12 ) ( 0 ) is calculated from $$\eta _{12}^{(0)}$$ η 12 ( 0 ) using $$A_{12}^*$$ A 12 ∗ values for the nonspherical potential, the impact is several percent. Moreover, the experimentally based $$\eta _{12}^{(0)}$$ η 12 ( 0 ) and $$(\rho D_{12})^{(0)}$$ ( ρ D 12 ) ( 0 ) data agree with theoretically calculated values for the nonspherical potentials. | Determination of the Binary Diffusion Coefficients and Interaction Viscosities of the Systems Carbon Dioxide–Nitrogen and Ethane–Methane in the Dilute Gas Phase from Accurate Experimental Viscosity Data Using the Kinetic Theory of Gases | 10.1007/s10765-023-03233-y |
2023-07-29 | The inferior alveolar nerve can be damaged during dental procedures, leading to symptoms, such as tingling, numbness, and reduced quality of life. Recovery depends on factors such as medications, surgery, and photobiomodulation therapy. Photobiomodulation therapy has shown the potential to improve nerve function and reduce regeneration time; however, there is no standard treatment protocol yet. This study aimed to examine the effect of diode lasers on nerve regeneration in patients with axonetmesis injuries. In this experiment on animals, Wistar rats’ damaged sensory systems were treated with lasers to restore them. Animals were randomly divided into six groups: a sham group, a control group, and four laser treatment groups(1st group: performed every day, 10 sessions; 2nd group: performed every 2 days, 10 sessions; 3rd group: performed every day, 20 sessions; and 4th group: performed every 2 days, 20 sessions). Sensory function was determined using the Semmes–Weinstein monofilament test, which was repeated after the surgical procedure. The results showed that the 20-session group had the best improvement, most closely resembling the group without sensory test damage. The histomorphometric results showed that the number of axons was significantly lower in the group that received 10 daily sessions and in the control group than in the undamaged nerve. Axon diameter was lower in all groups than in the sham group. In conclusion, the remarkable aspect of this study is that consecutive-day 20-session laser treatment showed better improvement than the over-the-day 20-session treatment protocol. | The effect of different treatment protocols with diode laser on regeneration in axonetmesis ınjuries of the ınferior alveolar nerve: an animal study | 10.1007/s10103-023-03834-x |
2023-07-28 | Optimal root system architecture (RSA) is essential for vigorous growth and yield in crops. Plants have evolved adaptive mechanisms in response to low phosphorus (LP) stress, and one of those is changes in RSA. Here, more than five million single-nucleotide polymorphisms (SNPs) obtained from whole-genome re-sequencing data (WGR) of an association panel of 370 oilseed rape ( Brassica napus L.) were used to conduct a genome-wide association study (GWAS) of RSA traits of the panel at LP in “pouch and wick” system. Fifty-two SNPs were forcefully associated with lateral root length (LRL), total root length (TRL), lateral root density (LRD), lateral root number (LRN), mean lateral root length (MLRL), and root dry weight (RDW) at LP. There were significant correlations between phenotypic variation and the number of favorable alleles of the associated loci on chromosomes A06 (chrA06_20030601), C03 (chrC03_3535483), and C07 (chrC07_42348561), respectively. Three candidate genes ( BnaA06g29270D , BnaC03g07130D , and BnaC07g43230D ) were detected by combining transcriptome, candidate gene association analysis, and haplotype analysis. Cultivar carrying “CCGC” at BnaA06g29270DHap1 , “CAAT” at BnaC03g07130DHap1 , and “ATC” at BnaC07g43230DHap1 had greater LRL, LRN, and RDW than lines carrying other haplotypes at LP supply. The RSA of a cultivar harboring the three favorable haplotypes was further confirmed by solution culture experiments. These findings define exquisite insights into genetic architectures underlying B. napus RSA at LP and provide valuable gene resources for root breeding. | Genome-wide association study reveals candidate genes controlling root system architecture under low phosphorus supply at seedling stage in Brassica napus | 10.1007/s11032-023-01411-2 |
2023-07-27 | Propylene carbonate (PC)-based electrolytes have exhibited significant advantages in boosting the low-temperature discharging of graphite-based Li-ion batteries. However, it is still unclear whether they can improve the charging property and suppress lithium plating. Studying this topic is challenging due to the problem of electrochemical compatibility. To overcome this issue, we introduced graphite with phase defects. The results show that the pouch-type full batteries using PC-based electrolyte exhibit steady performance over 500 cycles and can be reversibly charged over 30 times at −20 °C with an average Coulombic efficiency of 99.95%, while the corresponding value for the conventional ethylene carbonate (EC)-based electrolyte sample is only 31.20%. This indicates that the use of PC-based electrolyte significantly suppresses lithium plating during low-temperature charging. We further demonstrate that the improved performance is mainly attributed to the unique solvation structure, where more $${\rm{PF}}_6^ -$$ PF 6 − anions participate in solvation, leading to the formation of a stable F-rich solid state electrolyte interface on the graphite surface and a lower reduction tendency of Li + ions. This work inspires new ideas for the design of PC-based electrolytes for low-temperature charging and fast-charging batteries. | Boosting reversible charging of Li-ion batteries at low temperatures by a synergy of propylene carbonate-based electrolyte and defective graphite | 10.1007/s12274-023-5968-4 |
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