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2023-03-13 | Straw biorefinery offers economical and sustainable production of chemicals. The merits of cell immobilization technology have become the key technology to meet d -lactic acid production from non- detoxified corn stover. In this paper, Low acyl gellan gum (LA-GAGR) was employed first time for Lactobacillus bulgaricus T15 immobilization and applied in d -lactic acid (D-LA) production from non-detoxified corn stover hydrolysate. Compared with the conventional calcium alginate (E404), LA-GAGR has a hencky stress of 82.09 kPa and excellent tolerance to 5-hydroxymethylfurfural (5-HMF), ferulic acid (FA), and vanillin. These features make LA-GAGR immobilized T15 work for 50 days via cell-recycle fermentation with D-LA yield of 2.77 ± 0.27 g/L h, while E404 immobilized T15 can only work for 30 days. The production of D-LA from non-detoxified corn stover hydrolysate with LA-GAGR immobilized T15 was also higher than that of free T15 fermentation and E404 immobilized T15 fermentation. In conclusion, LA-GAGR is an excellent cell immobilization material with great potential for industrial application in straw biorefinery industry. Graphical Abstract | Low acyl gellan gum immobilized Lactobacillus bulgaricus T15 produce d-lactic acid from non-detoxified corn stover hydrolysate | 10.1186/s13068-023-02292-5 |
2023-03-13 | Ultra-low permittivity ( κ ) materials have broad application prospects in the microelectronic fields. In this study, we prepared microporous polyimide-based composite membranes with ultra-low permittivity by incorporating a trace of cage-like Phenyl-POSS (POSS) into fluorinated polyamic acid (PAA).The effects of POSS incorporation on their dielectric properties correlated with the characteristics of the free volume defects of composite membranes have been investigated by positron annihilation technique. Incorporating POSS with hollow core into PI can effectively improve the free volume size and the relative volume fraction of composite membranes, which optimizes their low dielectric properties, but reduces their dielectric breakdown strength. The membrane with 3 wt % POSS presents an ultra-low permittivity ( κ = 1.77 at 10 4 Hz) and maintains excellent mechanical properties . As POSS-doping amount reaches 5wt% , POSS agglomerates in composite membranes, resulting in a rebound in its permittivity. The incorporation of POSS reduces the tensile strength of composite membranes, which can be attributed to the fact that the rigid phenyl-POSS dispersing in the matrix weakens the interaction between the molecular chains of PI. The experimental results can provide valuable information for improving the dielectric properties of polyimide-based membranes in future. | Preparation and characterization of low-permittivity polyimide-based composite membrane | 10.1007/s10965-023-03508-w |
2023-03-13 | We provide upper and lower bounds on the lowest free energy of a classical system at given one-particle density $$\rho (x)$$ ρ ( x ) . We study both the canonical and grand-canonical cases, assuming the particles interact with a pair potential which decays fast enough at infinity. | Classical Density Functional Theory: Representability and Universal Bounds | 10.1007/s10955-023-03086-7 |
2023-03-13 | Nanoparticles can enhance the intensity of susceptible vibrational modes through electromagnetic or chemical enhancement mechanisms responsible for the SERS effect (Surface-enhanced Raman spectroscopy). In the present work, copper nanoparticles (CuNP) with diameters between 3 and 10 nm were obtained by a simple method using rongalite and gelatin. The UV–Vis spectrum showed a well-defined absorption band centered at 570 nm, attributed to the surface plasmon resonance (SPR) of CuNP in a colloidal solution. The SERS effect was analyzed on the pyridine (Py) molecule, observing an enhancement in the radial breathing mode of Py. Complementarily, Cu 4n clusters (with n = 1–5) were modeled under the DFT (Density Functional Theory) framework at the B3LYP (Becke, 3-parameter, Lee–Yang–Parr) approximation level in combination with the LANL2DZ base set (Los Alamos National Laboratory 2 Double-Zeta). After analyzing the molecular descriptors, the Cu 4n -Py interaction study provided hints of SERS behavior. | Experimental and DFT studies of copper nanoparticles as SERS substrates | 10.1007/s00339-023-06531-2 |
2023-03-08 | It has been shown that long non-coding RNA (lncRNA) LINC00659 was markedly upregulated in the peripheral blood of patients with deep venous thrombosis (DVT). However, the function of LINC00659 in lower extremity DVT (LEDVT) remains to be largely unrevealed. A total of 30 inferior vena cava (IVC) tissue samples and peripheral blood (60 ml per subject) were obtained from LEDVT patients ( n = 15) and healthy donors ( n = 15), and then LINC00659 expression was detected by RT-qPCR. The results displayed that LINC00659 is upregulated in IVC tissues and isolated endothelial group cells (EPCs) of patients with LEDVT. LINC00659 knock-down promoted the proliferation, migration, and angiogenesis ability of EPCs, while an pcDNA-eukaryotic translation initiation factor 4A3 (EIF4A3), a EIF4A3 overexpression vector, or fibroblast growth factor 1 (FGF1) small interfering RNA (siRNA) combined with LINC00659 siRNA could not enhance this effect. Mechanistically, LINC00659 bound with EIF4A3 promoter to upregulated EIF4A3 expression. Besides, EIF4A3 could facilitate FGF1 methylation and its downregulated expression by recruiting DNA methyltransferases 3A (DNMT3A) to the FGF1 promoter region. Additionally, LINC00659 inhibition could alleviate LEDVT in mice. In summary, the data indicated the roles of LINC00659 in the pathogenesis of LEDVT, and the LINC00659/EIF4A3/FGF1 axis could be a novel therapeutic target for the treatment of LEDVT. | LINC00659 exacerbates endothelial progenitor cell dysfunction in deep vein thrombosis of the lower extremities by activating DNMT3A-mediated FGF1 promoter methylation | 10.1186/s12959-023-00462-x |
2023-03-03 | Although the road network in India has improved a lot in last three–four decades, still the connectivity in the rural parts of the country needs to be given more focus. The Government of India has launched the Pradhan Mantri Gram Sadak Yojana for development of the roads in the interior of rural part of the country. This scheme focusses on the low-cost and labour-intensive technology for the sustainable development of the mode of communication in such areas. This paper presents an experimental investigation on the strength characterization of construction of grout macadam for construction of rigid pavement in interior parts of the country catering to low traffic volume. Firstly, the design of cementitious grout mix was carried out and thereafter, the optimum grout mix was poured onto the overlaid compacted aggregate of different grade proportions. The resulting grouted concrete macadam was tested for compressive and flexural strength. It was observed that the properly designed grouted macadam using industrial waste material such as fly ash can be considered as an alternative material for the construction of low traffic volume. | Strength evaluation of cementitious grout macadam as a concrete pavement material for low-volume roads in India: a preliminary study | 10.1007/s41062-023-01082-0 |
2023-03-03 | Intervertebral disc degeneration (IDD) has been identified as one of the predominant factors leading to persistent low back pain and disability in middle-aged and elderly people. Dysregulation of Prostaglandin E2 (PGE2) can cause IDD, while low-dose celecoxib can maintain PGE2 at the physiological level and activate the skeletal interoception. Here, as nano fibers have been extensively used in the treatment of IDD, novel polycaprolactone (PCL) nano fibers loaded with low-dose celecoxib were fabricated for IDD treatment. In vitro studies demonstrated that the nano fibers had the ability of releasing low-dose celecoxib slowly and sustainably and maintain PGE2. Meanwhile, in a puncture-induced rabbit IDD model, the nano fibers reversed IDD. Furthermore, low-dose celecoxib released from the nano fibers was firstly proved to promote CHSY3 expression. In a lumbar spine instability-induced mouse IDD model, low-dose celecoxib inhibited IDD in CHSY3 wt mice rather than CHSY3 −/− mice. This model indicated that CHSY3 was indispensable for low-dose celecoxib to alleviate IDD. In conclusion, this study developed a novel low-dose celecoxib-loaded PCL nano fibers to reverse IDD by maintaining PGE2 at the physiological level and promoting CHSY3 expression. | Low-dose celecoxib-loaded PCL fibers reverse intervertebral disc degeneration by up-regulating CHSY3 expression | 10.1186/s12951-023-01823-4 |
2023-03-02 | A new isochoric apparatus was developed for measuring PvT properties of refrigerants from 240 K to 410 K. This temperature range extends measurements below ambient (~ 300 K) and overlaps with the range of other isochoric apparatuses in NEXT-RP centre of I2CNER, Kyushu University. PvT properties of four refrigerants (1,1,1,2-tetrafluoroethane, R-134a; pentafluoroethane, R-125; trifluoromethane, R-23 and 2,3,3,3-tetrafluoropropene, R-1234yf) were measured for the inner volume calculation and validation exercise. Vapour pressures of 1,1-difluoroethene (R-1132a) were measured between 240 K and 296 K (14 data points). All property measurements were conducted for heating up and cooling down phases. The expanded uncertainty values of temperature, pressure and density using the new isochoric apparatus are U ( T ) = 10 mK, U ( p ) = 1 kPa and U r ( ρ ) = 0.002, respectively, where the coverage of 2 was adopted for 95% confident levels. The measured vapour pressures were fitted using Wagner-type and Antoine-type equations and compared with the published data. | Vapour Pressure Measurements and Correlations for 1,1-Difluoroethene (R-1132a) at 240–296 K using a Newly Developed Isochoric Apparatus | 10.1007/s10765-023-03167-5 |
2023-03-01 | The impeller material FV520B-hardened stainless steel is a typical difficult-to-machine material. During the cutting process, the force and thermal load are large, and the chip breaking is difficult, resulting in poor processing quality and serious tool wear. Low temperature cooling can improve the machinability of materials by significantly reducing the temperature of the cutting zone. It is an important development direction of clean cutting in the future. In this paper, the effects of low temperature cooling (18 ~ − 196℃) on cutting machinability and chip morphology evolution of FV520B were systematically studied from macroscopic and microscopic aspects by setting triaxial milling and orthogonal turning experiments respectively based on low-temperature jet formed by mixing liquid nitrogen and compressed air. The experimental results show that liquid nitrogen cryogenic cutting can significantly improve the machinability of material FV520B and promote the formation of serrated chips. Under the condition of cutting speed of 80 m/min, axial cutting depth of 1 mm and feed per tooth of 0.25 mm/r, the cutting force, cutting vibration, and surface roughness of FV520B at − 100℃ are reduced by 30%, 62%, and 18% respectively compared with those at 18℃. When the cutting speed is 80 m/min, the axial cutting depth is 1 mm, and the feed per tooth is 0.1 mm/z, the tool life at − 100℃ is 43% higher than that at 18℃. With the increase of cutting speed and the decrease of jet temperature, the serration degree, pitch, and shear angle of chips increase and the deformation coefficient of chips decreases. | Machinability and chip morphology evolution of hardened stainless steel using liquid nitrogen cryogenic | 10.1007/s00170-022-10765-4 |
2023-03-01 | The gasification of solid urotropine was experimentally studied at filtering a high-temperature flow of carbon dioxide through it. It was shown that with an increase in the temperature of the filtered gas from 650 to 920 K, the time of urotropine gasification decreased and the average gasification rate increased from 0.38 to 1.25 g/s, leading to an increase in the flow of urotropine gasification products. The maximum achieved value of the mass of urotropine gasification products was 0.8 g per 1 g of incoming gas. In the temperature range of 480–530 K, intensive gasification of urotropine occurred, while the temperature of the gaseous products leaving the reactor remained practically unchanged. The amount of noncondensable gaseous gasification products did not exceed 1% of the initial mass of the sample. | Experimental study of urotropine gasification in CO2 flow at different temperatures | 10.1134/S0869864323020142 |
2023-03-01 | A comprehensive investigation of the characteristics of clay from the Gurlan deposit showed that in a chemical formulation Gurlan hydromicaceous clay possesses a relatively high content of iron oxide and alkali oxides as well as fine dispersity and a small amount of finely dispersed free quartz, which make this clay readily fusible. It was also found that the Gurlan clay can be used as a low-temperature fluxing component, instead of cullet, erklez [glass stones], nepheline syenite, etc., in the development of ceramic compositions. | Gurlan Hydromicaceous Clay — Low-Temperature Flux in Ceramic Production | 10.1007/s10717-023-00543-3 |
2023-03-01 | The surface layer modification of materials and coatings by ion beams is used in many fields of science and technology. The high-intensity implantation by ion beams with high power density and submillisecond duration, implies a significant pulsed heating of the irradiated surface layer, followed by its cooling due to the heat removal deep in the material thanks to its thermal conductivity and the implementation of repetitivelypulsed radiation-enhanced diffusion of atoms to depths exceeding the projective ion range. Based on the numerical simulation, the paper studies the temperature field dynamics in a silicon target at single-pulse and repetitively-pulsed submillisecond ion beams with 109 W/m2 pulsed power density. Temperature conditions are determined for the ion-implanted layer, which correspond to that of the radiation-induced diffusion of implanted elements, while the temperature in the matrix material does not lead to a deterioration of its microstructure and properties. | Numerical Simulation of Temperature Field Dynamics in Single-Crystal Silicon at Repetitively-Pulsed High-Intensity Ion Implantation and Energy Impact on the Surface Layer | 10.1007/s11182-023-02843-1 |
2023-03-01 | C ommercial cylindrical mesoporous silica pellets (3 mm diameter by 3–6 mm length) were modified by coring the pellets and inserting a 1 mm diameter copper wire along the long axis of the pellet, to give a pseudo core–shell support. While there were negligible differences in the thermal conductance of the two supports, the volumetric thermal capacitance of the core–shell support was 4.1 times greater than the unmodified silica. Fischer–Tropsch synthesis (FTS) catalysts comprised of 16 wt% Co and 1.5 wt% Ru immobilized on the native pellets (control catalyst, CT) or on the core–shell support (CS-Cu catalyst) were prepared, placed in a tubular packed-bed reactor and reduced with H 2 at 400 °C. The catalysts were conditioned for FTS (255 °C; 10 atm; H 2 /CO = 2; GSV 510 h −1 ) by cooling to 150 °C, changing to a syngas atmosphere, and slowly ramping to the run temperature of 255 °C over 8 h. Measurements of the catalyst bed temperature and furnace temperature during the activation and run time revealed frequent and large temperature spikes (∆T ~ 70 °C) in the CT bed, especially in the first 12 h of operation. In comparison, runs using the CS-Cu catalyst experienced fewer and less substantive temperature spikes (∆T ~ 30 °C). From the thermal data and the FTS productivity data, it was clear that the CT catalyst experienced a substantially greater degree to deactivation due to the thermal spikes than the CS-Cu catalysts. At similar conversions, the CS-Cu showed 50% greater productivity (g product /g Co – h) and a small but reproducible improvement in C 5+ selectivity (52–55 wt%). Notably, the CS-Cu catalyst gave an appreciably smaller amount of the olefinic product (3 vs 15%). The thermal capacitance of the CS-Cu clearly moderates the negative consequences of local exotherms in the catalyst bed, especially during the activation phase of the FTS run. | Effect of a High Thermal Capacitance Core–Shell Structure on Co-Ru/SiO2 Catalyst for Low Temperature Fischer–Tropsch Synthesis | 10.1007/s11244-023-01797-5 |
2023-03-01 | The low-temperature operation of lithium-ion batteries (LIBs) is a challenge in achieving high-stability battery technology. Moreover, the design and analysis of low-temperature electrolytes are impeded by the limited understanding of various solvent components and their combinations. In this study, we present a data-driven strategy to design electrolytes with high ionic conductivity at low temperature using various machine-learning algorithms, such as random forest and feedforward neural networks. To establish a link between prediction of electrolyte chemistry and cell performance of LIBs, we performed parameter-free molecular dynamics (MD) prediction of various salt concentrations and temperatures for target solvents. Finally, electrochemical modeling was performed using these properties as the required material parameters. Combining works of the fully parameterized Newman models, parameter-free MD, and data-driven prediction of electrolyte chemistry can help measure the discharge voltage of batteries and enable in silico engineering of electrolyte development for realizing low-temperature operation of LIBs. | Data-driven designs and multi-scale simulations of enhanced ion transport in low-temperature operation for lithium-ion batteries | 10.1007/s11814-022-1364-0 |
2023-03-01 | Gas breakthrough pressure is a significant parameter for the gas exploration and safety evaluation of engineering barrier systems in the carbon dioxide storage, remediation of contaminated sites, and deep geological repository for disposal of high-level nuclear waste, etc. Test for determining gas breakthrough pressure is very difficult and time-consuming, due to the low/ultra-low conductivity of the specimen. It is also difficult to get a comprehensive and high-precision model based on limited results obtained through individual experiments, as the measurements of gas breakthrough pressure were influenced by many factors. In this study, a collected database was built that covered a lot of former test data, and then, two models were developed by the random forest (RF) algorithm and multiexpression programming (MEP) method. The MEP model constructed with explicit expressions for the gas breakthrough pressure overcame the drawbacks of common “black box” models. Meanwhile, five significant indicators were selected from ten common features using the permutation importance algorithm. The RF model was interpreted by the Shapley value and the PDP/ICE plots, while the MEP model was analyzed through the proposed explicit expression, showing strong consistence with that in former studies. Finally, robustness analysis was conducted, and stability of the proposed two models was verified. | Machine learning-based models for predicting gas breakthrough pressure of porous media with low/ultra-low permeability | 10.1007/s11356-022-24558-5 |
2023-03-01 | With natural limonite as the precursor and an ammonium tungstate hydrate as modification, the W/limonite composite catalysts were synthesized by the impregnation method. Their structures and properties were systematically characterized and analyzed; the denitrification activity and resistance to water and sulfur on catalysts were investigated. The results indicated that the W/limonite composite with W/Fe mass ratio of 9% and calcination temperature of 300 °C had highly catalytic activity, enhanced resistance to sulfur and water. The NO conversion efficiency was maintained over 85% with NO initial concentration of 500 ppm, the gas hourly space velocity (GHSV) of 36,000 h −1 , and reaction temperature of 100 °C, while it was greater than 98% with addition of 200 ppm SO 2 and 3 vol. % H 2 O at the reaction temperature of 250 °C. The superior performance was mainly ascribed to the formation of W-OH species and W = O species with wide dispersion on the surface of goethite or in Fe 2 O 3 lattice defects, to generate more acidic hydroxyl groups and more oxygen defects and strong acidity Brønsted for the SCR reaction. | Tungsten modified natural limonite catalyst for efficient low-temperature selective catalytic reduction of NO removal with NH3: preparation and characterization | 10.1007/s11356-022-24755-2 |
2023-03-01 | Fatigue failures of structural materials pose enormous risks to in-service structures, as well as human lives. The development of advanced durable structural materials with fatigue resistance has important social impact. The novel concept of high-entropy alloys (HEAs) has engendered considerable attention due to their exhibited unusual mechanical properties, and correspondingly opening a new road to design fatigue-resistant structural materials. The present work discusses and reviews the current findings on fatigue behavior and mechanisms of HEAs. Based on the understanding of fatigue-resistant favorable deformation mechanisms in HEAs, the perspectives from the viewpoint of materials design are provided to advance the development of fatigue-resistant HEAs, and future works are also suggested. | Fatigue Behavior and Mechanisms of High-Entropy Alloys | 10.1007/s44210-022-00008-2 |
2023-03-01 | The toughened poly(L-lactic acid)/poly(butylene succinate-butylene terephthalate) (PLLA/PBST) blend with enhanced melt strength and excellent low temperature toughness and strength was prepared by melt compounding through in situ compatibilization reaction in presence of multifunctional epoxy compound (ADR). The PLLA/PBST blend was an immiscible system, and the compatibility of the PLLA/PBST blend was improved after adding ADR. FTIR and GPC curves confirmed the formation of the PLLA- g -PBST copolymer, which improved the interfacial bonding of the blend and therefore the PLLA/PBST/ADR blend showed excellent melt strength and mechanical properties. For the PLLA/PBST/ADR blend with 70/30 PLLA/PBST content, the complex viscosity increased significantly with increasing ADR content. Moreover, the tensile strength, elongation at break and impact strength all increased obviously with increasing the ADR content. The elongation at break of the blend reached the maximum value of 392.7%, which was 93.2 times that of neat PLLA. And the impact strength of the blend reached the maximum value of 74.7 kJ/m 2 , which was 21.3 times that of neat PLLA. Interestingly, the PLLA/PBST/ADR blend exhibited excellent low-temperature toughness and strength. At −20 °C, the elongation at break of the PLLA/PBST/ADR blend was as high as 93.2%, and the impact strength reached 18.8 kJ/m 2 . Meanwhile, the tensile strength of the blend at low temperature was also high (64.7 MPa), which was beneficial to the application of PLA in the low temperature field. In addition, the PLLA/PBST/ADR blend maintaind good biodegradability, which was of great significance to the wide application of PLLA. | Superior Toughened Biodegradable Poly(L-lactic acid)-based Blends with Enhanced Melt Strength and Excellent Low-temperature Toughness via In situ Reaction Compatibilization | 10.1007/s10118-022-2862-6 |
2023-03-01 | Conductive polymer coatings have exhibited great potential for wearable electromagnetic interference (EMI) shielding fabrics. Here, we report an efficient yet simple strategy to improve EMI shielding performances of polypyrrole (PPy) coated fabrics by the low-temperature in-situ polymerization of Py. The PPy coating polymerized at 0 °C results in a uniform and compact microstructure which confers the coated fabric with better air permeability, flexibility and lighter weight than the PPy modified fabric obtained at higher temperature. Moreover, the low-temperature treatment of PPy coated fabric enhances its electrical conductivity due to a high doping level of PPy. The EMI shielding performance of PPy coated fabric polymerized at 0 °C reaches 26.4 dB, demonstrating 63.47% enhancement of that fabricated from 20 °C at the same deposition cycle. In addition, the PPy coated fabric obtained from low temperature demonstrates more stable and durable EMI shielding properties than that obtained at high temperature. This work provides insights into fabricating conductive polymer composites with high EMI performances for intelligent integrated equipment as well as human health protection. | Low-temperature treated polypyrrole coated cotton fabrics for efficient electromagnetic interference shielding | 10.1007/s10570-023-05052-8 |
2023-03-01 | Abstract The issues of penetration of a low-melting metal into workpieces made of iron–copper and iron–carbon porous materials are considered: the chemical composition, mechanical properties, and density of the obtained material are determined by the composition and density of the pressing, the regime of preliminary sintering. The influence of an increase in temperature of preliminary sintering is considered, under the impact of which the plasticity and strength of the workpieces increase. At the same time, metal bonds that have appeared as a result of preliminary sintering are maintained during impregnation and the further increase in the properties occurs due to the closure of pores and the formation of new bonds. | The Structure and Properties of Materials Obtained by Impregnation | 10.1134/S1995421223010288 |
2023-03-01 | The effect of film material thermal conductivity on the melting threshold of the film-substrate system depending on the film thickness during a low-energy high-current electron beam (LEHCEB) irradiation is analyzed based on the numerical solution of the one-dimensional nonstationary heat equation with a volumetric thermal source. The experimentally obtained waveforms of the beam current at the collector and the accelerating voltage are used to simulate the heating source. The film thermal conductivity is numerically varied in a wide range, overlapping the entire range for real materials. The dependence of the melting threshold of a homogeneous material on the thermal conductivity is determined. The general behavior regularities of the film and substrate melting thresholds in dependence of the film thickness are established. | Melting Thresholds of the Film-Substrate System Irradiated with a Low-Energy High-Current Electron Beam | 10.1007/s11182-023-02848-w |
2023-03-01 | Results are provided for determining standard mechanical properties, cold resistance, and crack resistance properties of base metal and a heat-affected zone, and corrosion-mechanical strength of new cold-resistant steels with yield strength of at least 420, 460, 890 and 960 MPa. Results are given for studying ferritic-bainitic and bainitic-martensitic parameters of the structure of sheets from low- and sparingly-alloyed high-strength steels of various thicknesses. The low-alloy steel developed with a yield strength of at least 420 and 460 MPa with the code Arc may be used for any components of marine Arctic structures without restriction at operating temperatures down to –40°C. The high-strength steel with a yield strength of at least 890 and 960 MPa is recommended as a promising material for constructing underwater mining complexes and deep-water marine equipment. | Structure and Properties of New High-Strength Steels Produced by PAO Severstal’ for Arctic Structures | 10.1007/s11015-023-01450-2 |
2023-03-01 | In this study, an improved delayed detached eddy simulation (IDDES) method based on the shear-stress transport (SST) k-ω turbulence model has been used to investigate the underbody flow characteristics of a high-speed train operating at lower temperatures with Reynolds number Re =1.85×10 6 . The accuracy of the numerical method has been validated by wind tunnel tests. The aerodynamic drag of the train, pressure distribution on the surface of the train, the flow around the vehicle, and the wake flow are compared for four temperature values: +15 °C, 0 °C, −15 °C, and −30 °C. It was found that lower operating temperatures significantly increased the aerodynamic drag force of the train. The drag overall at low temperatures increased by 5.3% (0 °C), 11.0% (−15 °C), and 17.4% (−30 °C), respectively, relative to the drag at +15 −C. In addition, the low temperature enhances the positive and negative pressures around and on the surface of the car body, raising the peak positive and negative pressure values in areas susceptible to impingement flow and to rapid changes in flow velocity. The range of train-induced winds around the car body is significantly reduced, the distribution area of vorticity moves backwards, and the airflow velocity in the bogie cavity is significantly increased. At the same time, the temperature causes a significant velocity reduction in the wake flow. It can be seen that the temperature reduction can seriously disturb the normal operation of the train while increasing the aerodynamic drag and energy consumption, and significantly interfering with the airflow characteristics around the car body. 目的 受空气物理参数变化影响,低温下列车周围的流场特性与常温时存在差异。本文旨在对高速列车在低运行温度下的空气动力学性能及流场特性变化研究予以补充,探究低温对列车周围流场、列车风及列车尾流等方面的影响,以提高高速列车的抗高寒性能。 创新点 1. 将气体参数设置为低温环境,探究列车相比常温下的气动性能及周围流场的变化。2. 对比不同低温环境,探究不同程度低温对列车气动特性的影响。 方法 1. 通过基于SST k-ω湍流模型的IDDES数值计算方法对高速列车在雷诺数约为1.85×106的条件下低温运行的流动特性进行仿真。2. 依托后处理软件对不同温度下列车气动阻力、表面压力分布、车身周围流动及尾流等进行分析。3. 将结果进行比对,得出不同程度低温对列车气动特性的影响。 结论 1. 低温显著增加列车气动阻力;相比常温环境,0 °C、−15 °C及∑30 °C时的气动阻力分别增加了5.3%、11.0%和17.4%。2. 低温会增强车体周围的正负压力场,进而提高冲击流及流速快速变化区域的正负压力峰值。3. 低温时,列车风的作用范围缩小,涡量分布区域后移,而转向架舱内的气流流速增加。4. 低温时,列车的尾流速度降低。 | Effect of low operating temperature on the aerodynamic characteristics of a high-speed train | 10.1631/jzus.A2200166 |
2023-03-01 | Low-lipid microalgae such as Galdieria sulphuraria can survive extreme conditions suggesting low cultivation costs and potential industrial uses. However, so far, its energy potential for syngas and bio-oil production by pyrolysis and gasification is not fully explored. Herein, pyrolysis/gasification of Galdieria sulphuraria was studied by thermogravimetry and fixed bed reactor in a nitrogen atmosphere with/without downstream Co-Mo-based sour shift catalyst. The yield and higher heating value (HHV) of the product for each experimental run are determined and evaluated in terms of bio-char and bio-oil elemental analysis and syngas composition. Temperature greatly affects the product yield, conversion rate, and gas composition for pyrolysis experiments. However, even at high temperatures, the hydrogen content of the produced syngas is low. Low-temperature catalytic gasification experiments of Galdieria sulphuraria (500 °C) lead to the production of hydrogen-enriched syngas (41.7 vol% H 2 ) and high HHV (~ 30 MJ/kg) bio-oil with lower oxygen and nitrogen content. The results found in this work show the potential of Galdieria sulphuraria as a renewable energy resource for high-quality oil and syngas production. | Pyrolysis and Gasification Characteristics of Galdieria sulphuraria Microalgae | 10.1007/s12155-022-10449-7 |
2023-03-01 | The low-temperature phase stability of 97 mol.% ZrO 2 –3 mol.% Y 2 O 3 , 95 mol.% ZrO 2 –3 mol.% Y 2 O 3 –2 mol.% CeO 2 , 92.5 mol.% ZrO 2 –2.5 mol.% Y 2 O 3 –5 mol.% CeO 2 , 90 mol.% ZrO 2 –2 mol.% Y 2 O 3 –8 mol.% CeO 2 , and 88 mol.% ZrO 2 –12 mol.% CeO 2 materials in the ZrO 2 –Y 2 O 3 –CeO 2 system was studied. The phase stability was determined through accelerated aging in hydrothermal conditions for 7 h and 14 h. The evaluation criterion was the amount of the M-ZrO 2 phase that formed in the samples when aged in hydrothermal conditions. The properties of the materials were analyzed by X-ray diffraction and electron microscopy. The T-ZrO 2 → M-ZrO 2 phase transformation occurred to varying degrees in all samples except for the 88 mol.% ZrO 2 –12 mol.% CeO 2 sample after the first and second aging cycles. The smallest amount of M-ZrO 2 formed in the 90 mol.% ZrO 2 –2 mol.% Y 2 O 3 –8 mol.% CeO 2 sample. After both aging cycles, the fracture patterns for the 90 mol.% ZrO 2 –2 mol.% Y 2 O 3 –8 mol.% CeO 2 and 88 mol.% ZrO 2 –12 mol.% CeO 2 samples did not change significantly. With the complex stabilization of zirconia by yttria and ceria, the T-ZrO 2 → M-ZrO 2 phase transformation was controlled in the aging process by the number of oxygen vacancies resulting from the presence of yttria and by the stresses induced by the presence of ceria in the solid solutions. The number of oxygen vacancies decreased as ceria content in the ZrO 2 -based solid solutions increased, slowing down the rate of water diffusion and enhancing the low-temperature phase stability in the ZrO 2 –Y 2 O 3 –CeO 2 materials. The effectiveness of using the 90 mol.% ZrO 2 –2 mol.% Y 2 O 3 –8 mol.% CeO 2 and 88 mol.% ZrO 2 –12 mol.% CeO 2 composites for the microstructural design of medical materials with increased resistance to low-temperature degradation in humid environments was shown. | Effect of the ZrO2-Based Solid Solution on the Low-Temperature Phase Stability of ZrO2−Y2O3−CeO2 Materials | 10.1007/s11106-023-00359-4 |
2023-03-01 | Peat fires contribute to global warming and environmental destruction. Once ignited, the fires tend to spread deep, underground and are difficult to extinguish using solely water. Mixtures of soap-based firefighting agents and water are expected to improve suppression efficiency by enhancing the permeability of water, a cooling material. Nevertheless, peat fire suppression is rarely studied. We performed peat fire extinguishing experiments in Palangkaraya, Indonesia to evaluate the efficiency of an environmentally friendly soap-based agent; and we conducted field experiments on 1.5 m × 1.5 m as well as 7 m × 7 m of peatlands. We conducted firefighting activities by applying (1) groundwater as well as (2) a solution of groundwater and 1 vol% of a soap-based firefighting agent. Surface temperatures of peat fires were approximately 160°C and 66°C after initial firefighting activities using solely water and a 1 vol% soap-based solution, respectively. The quantity of water required to extinguish the fires was 7.2 L/m 2 using solely water, and decreased to 3.6 L/m 2 using the soap-based solution. The soap-based solution exhibited a higher heat removal effect on the peat soil surface and higher permeability into peat soil than solely water, and can therefore be used to quickly extinguish peat fires. 10 months after the experiment, experimental sites sprayed with the soap-based solution demonstrated recovery of vegetation to the same degree as the sites sprayed solely with water. Thus, the soap-based firefighting agent is environmentally friendly, has promising firefighting properties, and is a reasonable tool for mitigating peat fires. | Field Experimental Investigations on the Performance of an Environmentally Friendly Soap-Based Firefighting Agent on Indonesian Peat Fire | 10.1007/s10694-023-01381-z |
2023-03-01 | To clarify the wintering ability of the cactus Nopalea cochenillifera cv. Maya (edible Opuntia sp., common name “Kasugai Saboten”), we investigated the effects of temperature and antioxidant capacity on chilling acclimatization. We analyzed the anatomy of cladode chlorenchyma tissue of plants exposed to light under chilling. We found that chilling acclimatization can be achieved by exposure to approximately 15 °C for 2 weeks and suggest that it is affected by whether or not antioxidant capacity can recover. The overwintering cacti had the thinnest cuticle but firm cuticular wax, which is important in the acquisition of low temperature tolerance under strong light. In cacti with severe chilling injury, round swollen nuclei with clumping chloroplasts were localized in the upper part (axial side) of the cell, as though pushed up by large vacuoles in the lower part. In overwintering cacti, chloroplasts were arranged on the lateral side of the cell as in control plants, but they formed pockets: invaginations with a thin layer of chloroplast stroma that surrounded mitochondria and peroxisomes. Specific cellular structural changes depended on the degree of chilling stress and provide useful insights linking chloroplast behavior and structural changes to the environmental stress response. | Morphological and antioxidant responses of Nopalea cochenillifera cv. Maya (edible Opuntia sp. “Kasugai Saboten”) to chilling acclimatization | 10.1007/s10265-023-01437-9 |
2023-03-01 | The freezing–thawing damage of rock mass involves the coupling of temperature field, seepage field and stress field (THM) at low temperature. Based on water/ice phase transition theory and energy conservation principle, the expression of freezing rate is obtained. According to the law of conservation of mass, the law of conservation of energy and the principle of static equilibrium, the coupling governing equation of THM of fractured rock mass under freezing condition is obtained by using the dual-porosity medium theory. An example of underground LNG storage in low temperature condition is used to verify the proposed THM coupling model. The surrounding rock is regarded as a system composed of rock blocks and fracture media, and the equivalent thermal expansion coefficient method is used to simulate the frost heaving effect of ice-filled fractures. The influence of freezing process on the permeability coefficient of rock mass is considered in simulation. The distribution of temperature, stress and pore pressure under THM coupling condition at low temperature is studied. | A Fully Thermo-Hydro-Mechanical Coupling Simulation at Low Temperature in Underground LNG Storage | 10.1007/s10706-022-02320-5 |
2023-03-01 | Studying the evolution of the pore structure of coal during spontaneous combustion is of great value in further understanding the mechanism of coal spontaneous combustion (CSC) and its prevention. In this study, we selected three low-rank coals and used nuclear magnetic resonance (NMR) to visualize the macroscopic evolution of the pore structure of coal after heat treatment and to analyze the effect of temperature (25–500 °C) on the pore structure of coal, including porosity, permeability, and fractal dimensions. The obtained results show that the overall NMR signal in coal increases with increasing temperature, indicating that heat treatment can induce the enlargement, opening, and interconnection of pores and fractures in coal. The equivalent average pore radius ( r m ) of coal shows a positive correlation with temperature, with a substantial increase in r m , especially after temperatures above 200 °C. During heating, the porosity and permeability of all three coals tended to increase with temperature. At temperatures above 300 °C, the permeability of coal dramatically increases, predicting a higher fluid transport capacity. Furthermore, NMR multifractal theory was proposed for quantitative pore space dimensional characterization. The obtained results show that the fractal dimensions of the adsorption space of coal pores increase and then decrease with temperature during heating, while the fractal dimensions of percolation space are negatively correlated with temperature. In addition, the dimensions of adsorption space vary more strongly than those of percolation space, meaning that the adsorption capacity of low-rank coals is more significantly influenced by temperature. | Study on the evolution of the pore structure of low rank coal during spontaneous combustion | 10.1007/s11356-022-25069-z |
2023-03-01 | Pilot scale production of one-dimensional (FeS 2 ) n n− rods was performed by using an automatic 20 L vessel at 80 °C under atmosphere condition with the resource utilization of Fe-rich sludge. The sludge was simulated at lab-scale with chemical pure of ferric trichloride. After the sludge treatment, the corresponding rods were not formed at room temperature. But by heating at 80 °C, erdite rod was well-crystallized after 0.5 h by only adding Na halite, and KFeS 2 rod was crystallized weakly after 2 h and highly at 10 h with the addition of K halite. After 48 h heating, the rods grow radially to 300 nm for erdite, but to 5 μm for KFeS 2 . However, at room temperature, erdite rod was converted to high crystallized KFeS 2 in KOH water or ethanol solution, whilst the conversion of KFeS 2 rod to erdite also occurred in NaOH water solution, but terminated in NaOH ethanol solution, without any morphology change. It is also noted that with the presence of both Na and K halite, the rod was an intermediate of erdite to KFeS 2 with 1 μm length after heating at 100 °C but converted to 10-μm-length KFeS 2 crystal at the temperature of > 120 °C. The thermodynamic results confirmed that during the rod polymerization, the Fe(OH) 3 HS − formation was the sole rate-limiting step and showed a positive Gibbs value of 6.45 kJ/mol at room temperature and negative values at the temperature of > 48 °C. In summary, this method not only enabled the vaporization of waste Fe-rich sludge as value-added rods without generating any secondary waste but also showed a new route for the in situ conversion of erdite/KFeS 2 rods at room temperature. Graphical Abstract | Valorization of waste Fe-rich sludge as erdite/KFeS2 rods under atmosphere condition and evaluation of their mutual transformation | 10.1007/s11356-022-24330-9 |
2023-03-01 | Abstract Utilization of phenol-containing pyrolysis water (PW) formed as the by-product of biomass pyrolysis is challenging issue due to large number of various organic substances in its composition. Combustion of PW as part of coal-water fuel (CWF) is effective, but poorly studied solution, which allows to neutralize all contaminants. Current study is devoted to the ignition and combustion characteristics of CWF droplets with PW and 3 fractions obtained in different temperature ranges—<100, 100–150 and 150–200 °C. The PW was obtained by separation and sedimentation from industrial biochar-producing facility. The waste of coal facility was used as a solid component of CWF. The ignition and combustion of CWF was studied via the combustion chamber in the temperature range 500–800 °C as well as a CWF with distilled water as a reference sample. The use of PW resulted into an increase in CWF reactivity, which was reflected in a reduction in the ignition delay time (up to 50% at 500 °C and up to 90% at 800 °C) and the minimum ignition temperature (by 6.9% on average). The most prominent effect was observed for CWF with PW fraction obtained in temperature range 150–200 °C, the least—for fraction < 100 °C. The heating value of CWF due to substitution of distilled water on different PW fractions was increased by 0.1–1.4 MJ/kg. According to material and energy balances, the 16.2 wt% of PW should be used for CWF to ensure energy-sufficiency of the pyrolysis facility. Obtained results provide technical background for integration of such technology into pyrolysis technological cycle. Graphical Abstract | Utilization of Different Fractions of Pyrolysis Water in Coal Water Fuel for Additional Heat Recovery | 10.1007/s12649-022-01913-8 |
2023-03-01 | With the gradual promotion and the application of difficult-to-machine materials such as titanium matrix composites in the aerospace field, high-quality hole-making technology has become a major demand in aviation manufacturing. In order to improve the hole-making quality of TiBw/TC4 composites, asynchronous mixed frequency vibration-assisted hole-making (AMFVAHM) method is proposed. The process consists of two steps: ultrasonic vibration-assisted drilling (UVAD) base hole and low-frequency torsional vibration-assisted helical milling (LFTVAHM) target hole. Based on this process, the cutting trajectory modeling is established, and the hole-making experiment on TiBw/TC4 composites is conducted. The experimental data show that during the hole expansion stage, the maximum XY -plane average milling force decreases by 30.96% and the maximum axial average milling force decreases by 24.49% compared with conventional helical milling (HM) when the torsional vibration frequency and the milling frequency are the same in LFTVAHM. The hole-making experiment shows that AMFVAHM can reduce the chip size, tool wear, and some other defects such as entrance/exit burrs, scratches, and fractures of the hole wall. Comparing with HM and UVAD, the verticality of hole wall increases by 71.43% and 86.21%, the inlet damage decreases by 27.98% and 31.60%, the outlet damage decreases by 2.80% and 14.47%, the hole wall roughness ( R a ) decreases by 36.29% and 63.43%, and the maximum white layer thickness decreases by 19.99% and 67.66%. Meanwhile, AMFVAHM process not only reduces the cutting force and cutting temperature but also improves the hole-making quality due to the fretting friction effect of LFTVAHM in secondary hole expansion, which meets the need for high-quality hole-making of difficult-to-machine materials in practical engineering applications. | Experimental research on new hole-making method assisted with asynchronous mixed frequency vibration in TiBw/TC4 composites | 10.1007/s00170-022-10754-7 |
2023-03-01 | Environmental degradation of thermal barrier coatings (TBCs) by molten deposits, which include calcium magnesium alumino-silicates (CMAS), is one of the vital factors that result in the failure of thermal barrier coatings. This problem has been exacerbated due to increases in turbine engine inlet temperatures as a means to accommodate the demand for higher fuel efficiency. A new phase composite ceramic had been developed and evaluated for the topcoat of a durable thermal barrier coating (TBC) system with low thermal conductivity properties and improved erosion resistance. The primary goal of this research is to continue exploring the behavior of CMAS resistance of the phase composite TBC at high temperatures. The effects of CMAS attack and thermal exposure on the TBC degradation were investigated in experimental runs. In addition, a YAG-modified layer over the top of the TBC was applied in an attempt to improve the CMAS resistance of the TBC system. The evaluation of CMAS resistance was focused on the most important characteristics of coating microstructure including CMAS penetration, test condition factors, and mode of failure. The mechanisms for the CMAS infiltration and the TBC damages were discussed based on the analyses of the CMAS corroded samples in detail. | Evaluation of CMAS Resistance and Failure Behavior for Phase Composite Thermal Barrier Coatings | 10.1007/s11666-022-01474-1 |
2023-03-01 | Laminated glass has been introduced to improve the mechanical performance, in particular impact resistance, of float glass while maintaining its transparency. However, its rate-dependent behaviour has not been sufficiently understood and various methods have been used to model it. This study compares the response of three material models commonly used to model glass cracking implemented in industry-standard LS-DYNA software: a smeared fixed crack model with the Rankine failure criterion, the nonlocal failure criterion by Pyttel et al. and the Johnson-Holmquist model. The input parameters are taken from several published studies, so each model was tested in multiple validated settings. The response of the models is compared with values measured during an earlier experimental campaign. The reference experiments involved freely hanging full-scale samples, which eliminated the effect of structural supports and allowed more accurate validation of the numerical models. The response of two types of glass, i.e. annealed or heat-strengthened, and two types of interlayer, i.e., polyvinyl butyral or ethylene–vinyl acetate, was tested and is simulated herein. The time evolution of the contact force, specimen accelerations, and fracture patterns are discussed, demonstrating the main shortcomings of the three models in simulating destructive tests on laminated glass samples under low-velocity impact. | Numerical study on failure of laminated glass subjected to low-velocity impact | 10.1007/s40940-022-00210-z |
2023-03-01 | In this study, the reducing smelting of chromite concentrates by EAF-assisted metallothermic method was investigated. The effect of Al Powder and Al Dross addition amount, time, and the ratio of flux addition on the produced metal and slag compositions and metal recovery were investigated. It was seen that ferrochrome can be produced from fine-grained chromite concentrate by this method. As a result of EAF-assisted semi-pilot metallothermic smelting, the highest chromium content in produced alloys was 59.5 wt. %, while the highest chromium recovery from chromite concentrate to alloys was 76.7 wt. % in these experiments. Graphical Abstract | A Decarbonization Approach for FeCr Production | 10.1007/s40831-022-00632-7 |
2023-03-01 | A new 3D metal–organic framework (Nd-MOF) {[Nd 2 L 2 ]·2NH 2 (CH 3 ) 2 ·3H 2 O} was successfully established via a solvothermal method with Nd 3+ ion and 5-(bis(4-carboxybenzyl) amino)–isophthalicacid (H 4 L), and has also been characterized by X-ray diffraction, powder X-ray diffraction (PXRD), IR and photoluminescence(PL)spectrum. The neodymium ions are free of coordinated solvents, and the Nd-MOF exhibits strong near-infrared (NIR) fluorescence. Besides, Its NIR fluorescence property shows low temperature resistance, which is favorable for being used in the low temperature environment. Besides, the fluorescence lifetime of Nd-MOF is 6.03 μs, and the quantum yield is 1.2%. The small quantum yield may owe to large energy gap between the T1 of the ligand H 4 L and the resonance energy level 4 F 3/2 of the Nd 3+ ion, or due to large crystal size of the Nd-MOF. Graphical Abstract | Synthesis, Structure and Near Infrared Fluorescence Property of a New Nd-MOF Based on a Triangular Benzylamine Ligand | 10.1007/s10895-022-03048-4 |
2023-03-01 | MnFe 2-x Yb x O 4 nanoparticles ( x = 0, 0.025, 0.075, 0.1, 0.15, and 0.2) are synthesized using the co-precipitation method. The influence of rare earth Yb 3+ doping on the manganese ferrite is investigated by techniques such as x-ray diffraction (XRD) and field effect scanning electron microscopy (FESEM). The magnetic properties were measured using vibrating sample magnetometer (VSM) at temperatures of 5 K and 300 K. XRD results show the formation of undoped and Yb 3+ -doped manganese ferrite nanoparticles. Crystallite size calculated using XRD reveals that it is doping concentration dependent. FESEM images reveal the formation of faceted nanoparticles for undoped sample and spherical shape for x = 0.025–0.2. Energy-dispersive X-ray spectroscopy (EDS) shows that Yb 3+ ions are successfully incorporated into manganese ferrite. Saturation magnetization, coercivity, retentivity, squareness ratio, thickness of the dead layer, magnetic moment, and anisotropy constant are determined at 5 K and 300 K. These studies show dependence of these parameters on the amount of doping. | Effects of Yb3+ Doping on Structural, Morphological, and Temperature Dependent Magnetic Properties of MnFe2O4 Nanoparticles | 10.1007/s10948-023-06534-3 |
2023-03-01 | Biomethanation is a temperature-dependent process, and in the cold regions where temperature mostly remains below 20 °C, it acts as a crucial limiting factor. The biomethanation process with efficient cold-tolerant anaerobes and other advanced techniques, including reliable digester designs, cost-effective insulation strategies, and additives, can help increase methane production efficiency under low ambient temperature. In cold regions, traditional fuel sources like forest wood, charcoal, agricultural residues, or cow dung cakes are used for cooking and heating, leading to increased greenhouse gas emissions. Thus, biogas is a promising fuel to replace traditional fuels and helps reduce the greenhouse effect to a great extent. The current review article has highlighted the role of cold-tolerant methanogens, different digester designs with a special focus on insulation techniques, co-digestion, and additives. The review also discusses different upgradation techniques to generate pure methane as a substitute for natural gas. Additionally, life cycle assessment analysis is also carried out focusing on the reduction of greenhouse gas emissions to show higher biogas production over traditional biogas systems. Overall, the importance of improved biomethanation in cold regions has been discussed in this review article. Graphic abstract | Psychrophilic biomethanation for enhanced bioenergy production in cold regions | 10.1007/s10098-021-02223-8 |
2023-03-01 | In this study, the effect of induced electro-pulsing treatment (IEPT) on the microstructure evolution and corresponding changes in the mechanical properties of pre-stretched 5052-O aluminum alloy was investigated. Microstructural changes in the alloy were observed using electron backscatter diffraction, transmission electron microscopy, and scanning electron microscopy. The application of induced current significantly reduced the yield strength of pre-stretched specimens while the elongation increased. In terms of microstructure, more uniformly distributed dimples were observed after induced current application, which indicate the increased plasticity of the alloy. The average grain size and number of low angle grain boundaries increased with application of induced current. The texture types did not change, however, the cube-type texture became less pronounced, whereas brass-type and copper-type textures were enhanced. Furthermore, the dislocation density decreased and dislocation rearrangement occurred. Thus, IEPT provides a new way to alter the microstructure and mechanical properties of the deformed components. Graphical Abstract | Mechanical Properties and Microstructure Evolution of Pre-stretched Aluminum Alloy After Induced Electro-Pulsing Treatment | 10.1007/s12540-022-01259-9 |
2023-03-01 | Low-moisture foods such as spices, grains, and seeds constitute an important part of the human diet. Increased consumer concern for food safety and food quality has focused on the decontamination technologies required for low-moisture foods. Cold plasma treatment has been a promising novel technology in the food processing industry due to its advantages in safety, efficiency, versatility, and environmentally friendly nature. It has shown various capabilities on safety and quality control in low-moisture foods. This paper comprehensively reviewed the application of cold plasma in low-moisture foods, including inactivation of microorganisms, degradation of mycotoxins, influences on the quality of low-moisture foods, and promotion of seed germination. Cold plasma can inactivate the pathogenic microorganisms on the surface of low-moisture foods, by generating active species, ultraviolet radiation, and electric fields, which helps to extend the shelf life of foods while having minimal impact on food quality. Cold plasma technology is also an effective approach to detoxify mycotoxin-contaminated low-moisture foods by degrading various mycotoxins. With the manipulation of parameters for cold plasma generation, target functional properties of food products may be obtained. In addition, the application of cold plasma in seed germination is promising and could be of great significance to the global food crisis. This review also suggests that more systematic studies are needed to employ cold plasma in the low-moisture foods industry for selected applications. | The Application of Cold Plasma Technology in Low-Moisture Foods | 10.1007/s12393-022-09329-9 |
2023-03-01 | Currently, there is much concern about the recycling and processing of used complex chemical power sources (CPS) resulting from the use of mobile communication devices, electric vehicles, and various electronic devices. An environmentally friendly technology for the recycling of CPSs by multi-stage methods developed at the National Research Center “Kurchatov Institute” — IREA is presented. The technology involves opening, crushing, and grinding (with mechanical activation), followed by liquid–solid leaching and liquid–liquid extraction. The target product is a powdery precipitate containing compounds of cobalt (Co), lithium (Li), manganese (Mn), nickel (Ni), etc. The grinding stage (in a ball mill or a disintegrator) leads to the destruction of the particle structure, changing their specific surface area and porosity. As a result, the intensity and efficiency of the extraction processes increase. The textural characteristics (such as specific surface area, porosity, total pore volume, micro- and mesopore volume) of crushed and powdered samples containing graphite with inclusions of Co and Li compounds are determined. The methods implemented in the Micromeritics ASAP 2020 analyzer software such as BET, t-Plot, Dubinin–Radushkevich, Dubinin–Astakhov, Horvath–Kawazoe, and BJH are used. The calculated texture characteristics can be used to optimize the extraction of the target components from a mechanically activated powder during leaching followed by extraction. | Influence of the Adsorption Characteristics of Crushed and Mechanically Activated Powdered Chemical Power Sources on the Efficiency of Producing Cobalt and Lithium Compounds by Leaching and Extraction | 10.1007/s11015-023-01478-4 |
2023-03-01 | Throughout the period of operation of non-ferrous metal deposits, a significant amount of waste has been accumulated. The accumulated waste contains valuable metals in concentrations that allow considering them as valuable raw materials. However, it is worth noticing the presence of problems that previously did not allow for more complete extraction of the target components. Such problems include the presence of significant amounts of silicon dioxide in the form of a silicate matrix, the removal of which will allow the extraction of valuable components with the elimination of industrial waste areas. The paper considers a method for removing silicon from the polymetallic slags. According to the results of the work, it was found that silicon passes into solution in the form of ammonium hexafluorosilicate. Iron, aluminum, and a number of other components react with ammonium hydrofluoride, but do not leach into the solution due to their low solubility in the resulting system. After removing silicon, the solid residue was subjected to pyrohydrolysis to obtain a product that can be subjected to magnetic separation to obtain a magnetic iron concentrate and a non-ferrous metal concentrate. The formed concentrate can later be used to extract zinc, lead, silver, etc. The productive solution was directed to the deposition of silicon with the subsequent production of silicon dioxide. The resulting solution can be directed to evaporation in order to regenerate and reuse ammonium hydrodifluoride. | Low-temperature method for desiliconization of polymetallic slags by ammonium bifluoride solution | 10.1007/s11356-022-24230-y |
2023-03-01 | Thermoluminescence spectra in the temperature range 80–300 K were compared for lithium fluoride nanocrystals and crystals. Four and one band were observed in the spectra of nanocrystals and crystals, respectively. Thermoluminescence intensities integrated over the spectrum and temperature range were measured for two types of lithium fluoride samples in one of which radiation color centers with new properties could form and in the other of which they could not form. The intensity was found to be significantly higher in samples of the first type. | Low-Temperature Thermoluminescence of Lithium Fluoride Nanocrystals and Crystals | 10.1007/s10812-023-01501-1 |
2023-03-01 | Contemporaneous trends in the development of technologies for matting glass and products from matted glass are considered. An efficient glass matting technology has been developed using an alternative source of energy—low-temperature plasma. It is demonstrated that a high-quality matt surface of the type ‘frosty matting’ is formed by using iron powders with dispersivity 160 and 450 µm. The microstructure of the matted surface was investigated. Theoretical aspects of matting glass are considered. The technological parameters of matting are determined and the developed technology is shown to be economically efficient. | New Trends in Glass Matting Technologies | 10.1007/s10717-023-00530-8 |
2023-03-01 | This paper presents a sub-microwatt sub-bandgap voltage and current reference that can generate proportional-to-absolute-temperature (PTAT) and complementary-to-absolute-temperature (CTAT) currents concurrently. The voltage reference is derived from the process-insensitive silicon bandgap voltage of a bipolar junction transistor, whereas the current reference is made by combining PTAT and CTAT currents. Line regulation is improved by incorporating cascode devices without an operational amplifier (opamp). Fabricated in a standard 0.18-µm CMOS process, the proposed bandgap reference occupies an active area of 0.4 mm 2 . The current and voltage reference ( $${I}_{\mathrm{REF}}$$ I REF and $${V}_{\mathrm{REF}}$$ V REF ) are measured as 170 mV and 21 nA, respectively, while the start-up settling response is measured as 20 ms at room temperature. The average temperature coefficient of $${I}_{\mathrm{REF}}$$ I REF and $${V}_{\mathrm{REF}}$$ V REF is 79.8 ppm/°C and 87.93 ppm/°C across the temperature range from − 40 to 120 °C, respectively. The power consumption is 134 nW at the minimum supply voltage of 1.2 V. The power supply ripple rejection of $${V}_{\mathrm{REF}}$$ V REF is measured as − 10 dB at 100 kHz without any filtering capacitor, when the 1.6 V input line voltage is distorted by a 300-mVp-p ripple. The measured line sensitivity of the voltage and current reference is 0.142%/V and 0.757%/V, respectively. | A 134-nW Single BJT Bandgap Voltage and Current Reference in 0.18-µm CMOS | 10.1007/s00034-022-02158-5 |
2023-03-01 | Metal of twelve industrial melts of hot-rolled steel grades S315MC, S355MC is studied for steel metallurgical quality, structural state characteristics, and mechanical properties. On the basis of results obtained the possibility of more economical steel microalloying is demonstrated as well as directions for optimizing liquid and solid metal processing parameters. | Investigation of Production Technology for Hot-Rolled High-Strength Low-Alloy Automobile Sheet Steels to Improve Properties and Quality Indices at Reduced Cost | 10.1007/s11015-023-01465-9 |
2023-03-01 | The microstructure of cast billets and grinding balls fabricated from rail steels of different chemical compositions is studied. The samples are heat treated by annealing, quenching, and quenching with tempering. The microhardness and the structures of the samples after the treatments are compared. It is shown that chromium alloying above the standardized values causes development of dendritic segregation in the cast structures, which is reduced but not removed completely after the heating for rolling. Assessment of the microstructures and of the hardness of the grinding balls shows that the optimum composition for their production corresponds to rail steel 76KhF. | Analysis of Special Features of Microstructure of Grinding Balls Produced from Rejected Continuously Cast Rail Steel Billets of Different Chemical Compositions | 10.1007/s11041-023-00870-w |
2023-03-01 | The effect of thermocycling deformation and subsequent heat treatment on the microstructure and mechanical properties of low-carbon steels 10kp, St3ps and 20 is studied in cast condition and after rolling. Metallographic analysis of the steels is performed using an optical microscope at a magnification of ×140 and ×500. The microhardness of the structural components is measured. The mechanical properties of the steels are determined in tensile tests. It is shown that after the thermocycling treatment above the temperature Ac 3 all the structural components are refined. The strength of the forgings after the thermocycling treatment, quenching and low tempering increases by a factor of 1.7 – 2.4 at a satisfactory level of ductility. | Use of Thermocycling Deformation for Raising the Operating Properties of Low-Carbon Steel | 10.1007/s11041-023-00872-8 |
2023-03-01 | The thermoacoustic engine can convert low-grade thermal energy into acoustic energy. Applying the 4-stage engine could have higher efficiency in recovering the heat at lower-grade waste heat. Since the narrow channel radii of the stack are the heart of the thermoacoustic engine, this paper aims to indicate the optimum radii of the 4-stage thermoacoustic engine and predict the suitable low-temperature using the 4-stage engine stacks. The calculation procedure starts with setting the engine geometry and changing the hot end, assuming the ambient temperature to be 27 °C. The stability limit condition under which the spontaneous gas oscillation becomes neutral is calculated using the transfer method. The heating temperature, the angular frequency, the ratio of oscillatory pressure and velocity at the second, third, and fourth ambient end of the engine stack, and the ratio of oscillatory pressure and velocity at the last hot end of the engine stack have been calculated. Then, the obtained combination of the pressure and velocity is used to calculate the acoustic power at the ends of the engines. Finally, the second law of efficiency is applied to determine the engine performance. The results revealed that the onset heating temperature $$T_{{\text{h}}}$$ T h drops from 82 to 43 °C when $$r/\delta$$ r / δ rises from 0.5 to 1.2, while, by applying the 4-stage engine, the optimum $$r/\delta$$ r / δ shifted to be close to 1.2. The lowest onset temperature was 43 °C with 8% of the Carnot efficiency. | Numerical Study on the Effect of Stack Radii on the Low Onset Heating Temperature and Efficiency of 4-Stage Thermoacoustic Engine | 10.1007/s13369-022-06983-3 |
2023-03-01 | Purpose Low-radioactive material screening is becoming essential for rare event search experiments, such as neutrinoless double beta decay and dark matter searches in underground laboratories. A gaseous time projection chamber (TPC) can be used for such purposes with large active areas and high efficiency. Methods A gaseous TPC with a Micromegas readout plane of approximately $$20 \times 20$$ 20 × 20 $$\hbox {cm}^2$$ cm 2 is successfully constructed for surface alpha contamination measurements. Results We have characterized the energy resolution, gain stability, and tracking capability with calibration sources. Conclusion With the unique track-related background suppression cuts of the gaseous TPC, we have established that the alpha background rate of the TPC is ( $$0.13\pm 0.03$$ 0.13 ± 0.03 ) $$\times 10^{-6}$$ × 10 - 6 Bq/ $$\hbox {cm}^2$$ cm 2 , comparable to the leading commercial solutions. | A gaseous time projection chamber with Micromegas readout for low-radioactive material screening | 10.1007/s41605-022-00364-y |
2023-03-01 | In this work, the process of low salinity water injection (LSWI) into reservoirs at various salt concentrations was simulated in order to study the change in the oil recovery factor during oil production. The simulation results of the recovery factor were compared with the experimental data. The results demonstrated that the simulation data were in good agreement with the experimental results. In addition, the formation damage (rock permeability reduction) in carbonate core samples was evaluated through coreflood experiments during LSWI in the range of salt concentration and temperature of 1500–4000 ppm and 25–100 °C, respectively. In the worst scenario of LSWI, the rock permeability has reached about 83% of the initial value. Our previous correlation was used to predict the formation damage in LSWI. In this case, the R-squared value between predicted and experimental data of rock permeability ratios was more than 0.97. Furthermore, the recovery factor during LSWI was analyzed with and without the use of DTPMP scale inhibitor (diethylenetriamine penta (methylene phosphonic acid)), and various nanoparticles (TiO 2 , SiO 2 , Al 2 O 3 ). The results of the coreflood experiments showed that the use of scale inhibitor provides an increase in the recovery factor by more than 8%. In addition, the highest recovery factor was observed in the presence of SiO 2 nanoparticles at 0.05 wt.%. The oil displacement during LSWI in the porous media with SiO 2 particles was better than TiO 2 and Al 2 O 3 . The recovery factor in the presence of SiO 2 , TiO 2 , and Al 2 O 3 with DTPMP was 72.2, 62.4, and 59.8%, respectively. Among the studied nanoparticles, the lowest values of the oil viscosity and interfacial tension (IFT) between oil and water were observed when using SiO 2 . Moreover, the contact angle was increased by increasing the brine concentration. The contact angle with the use of SiO 2 , TiO 2 , and Al 2 O 3 at 0.05 wt.% was reduced by 11.2, 10.6, and 9.9%, respectively. | Experimental study of the low salinity water injection process in the presence of scale inhibitor and various nanoparticles | 10.1007/s13202-022-01583-1 |
2023-03-01 | The initial stages of room temperature growth of Pb overlayers on commercial Si(100) p $$(2\times 1)$$ ( 2 × 1 ) surface have been investigated using low-energy electron diffraction and low-energy electron microscopy (LEEM) techniques. A well-ordered reconstructed Si(100) p $$(10\times 2)$$ ( 10 × 2 ) surface phase has been observed for 0.5 monolayers of Pb deposition and is found to vanish for higher Pb coverages. We do not observe any island formation in our LEEM studies during the early stages of growth, unlike earlier studies on low-miscut substrates. Our dark-field LEEM experiments suggest the observed high step density with low terrace widths is responsible for this behaviour. | Growth and reconstructions of Pb ultrathin films on Si(100) surfaces | 10.1007/s12648-022-02439-4 |
2023-03-01 | Abstract This paper considers the change in the mechanical characteristics of polymer compositions based on polylactide (PLA) and low-density polyethylene before and after exposure to ultraviolet radiation and after incubation in the soil. It has been established that the photodegradation of polylactide–low-density polyethylene compositions occurs in both the amorphous and the crystalline phase of the PLA matrix, which leads to a deterioration in the physical and mechanical properties of the blends under investigation. Hydrolysis and mechanical damage, as well as soil microorganisms, are all factors that have a significant impact on the change in the structure of compositions and lead to the destruction of polylactide and materials based on it. | Mechanical Characteristics of Compositions Based on Polyethylene and Polylactide under the Action of Aggressive Environmental Factors | 10.1134/S1995421223010239 |
2023-03-01 | In this paper, high temperature hot rolling and weld simulations were performed in Al-killed and Ti-Zr-killed steels. The microstructure and impact toughness of the heat-affected zone (HAZ) of the two experimental steels were investigated, and the ferrite transformation behavior in HAZ was also observed. The characteristic inclusions in the Ti-Zr-killed steel were studied using electron probe microanalysis (EPMA) and electron backscatter diffraction (EBSD). The results suggested that the HAZ microstructure of the Al-killed steel consisted of coarse bainite ferrite (BF) and granular bainite (GB) packets. The HAZ microstructure of Ti-Zr-killed steel was significantly refined and mainly contained fine acicular ferrite (AF) and BF. The Ti-Zr-O + MnS inclusions were 0.3–2.1 μm and could effectively promote the formation of AF after the weld simulations. MnS had a specific orientation relationship: {111} MnS ║{0001} Ti-Zr-O , < 110 > MnS ║ < 2 $$\stackrel{\mathrm{-}}{1}\stackrel{\mathrm{-}}{1}$$ 1 - 1 - 0 > Ti-Zr-O with Ti-Zr-O inclusion, and its precipitation promoted the formation of the Mn-depleted zone (MDZ). AF formed around it. The formation of an interlocked AF structure in the HAZ of the Ti-Zr-killed steel obviously increased the proportion of high angle grain boundaries (HAGBs) and refined the average effective grain size of the HAZ microstructure. Consequently, the impact toughness of the Ti-Zr-killed steel had no deterioration, but the impact toughness of Al-killed steel had an obvious loss after the weld simulation with a heat input of 70 kJ/cm. The impact absorption energy of HAZ of Ti-Zr-killed steel was improved from 6 to 219 J compared to Al-killed steel. Graphical abstract | Inclusion Characteristics and Acicular Ferrite Formation in the Simulated Heat-Affected Zone of Ti-Zr-Killed Low-Carbon Steel | 10.1007/s12540-022-01254-0 |
2023-03-01 | Low-temperature stress can seriously impair plant physiology. Chilling injury leads to a complex array of cellular dysfunctions, and symptoms include chlorosis, sterility, loss of vigor, wilting, and even death of the plants. Furthermore, phosphorus limitations additionally halt the growth of plants. Low-temperature adaptive plant growth–promoting microbes through various direct and indirect mechanisms help in the survival of plants under stress conditions. The present investigation deals with isolation of P-solubilizing psychrotrophic bacteria from diverse cultivars of wheat grown in the Keylong region of Himachal Pradesh. A total of 33 P-solubilizing bacterial isolates were obtained. P-solubilizers were screened for different plant growth–promoting (PGP) attributes of K and Zn solubilization, production of IAA, siderophores, and different hydrolytic enzymes. Among 33 P-solubilizers, 8 efficient strains exhibiting multiple PGP attributes were used as bioinoculants for wheat under low-temperature stress in different in vitro and in vivo experiments. The psychrotrophic bacterial isolates positively influenced the growth and physiological parameters as well as nutrient uptake and yield of wheat and efficiently alleviated low-temperature stress. The potential of low-temperature stress adaptive and PGP microbes can be utilized in agricultural sector for amelioration of low-temperature stress and plant growth promotion. The present study deals with the isolation of psychrotrophic P-solubilizers with multiple PGP attributes and their role in alleviation of cold stress in wheat. | Alleviation of cold stress in wheat with psychrotrophic phosphorus solubilizing Acinetobacter rhizosphaerae EU-KL44 | 10.1007/s42770-023-00913-7 |
2023-03-01 | It is necessary to consider the dual problems of poor performance and low production efficiency that stem from the highly utilised water/gypsum ratios in the traditional preparation of phosphorus building gypsum (PBG)-based building materials. These problems cannot be easily overcome because that PBG tends to agglomerate at low water/gypsum ratios, which will hinder the hydration process and result in poor mechanical behaviour. In this study, a slurry-particle mixing system was proposed for the preparation of PBG-based building materials with homogeneous hydration at low water/gypsum ratios. More specifically, slurry-particle mixing system samples (SPMS) and pure PBG slurry samples (PPSS) with various water/gypsum ratios were prepared for comparative analysis. The results showed that the fluidity of SPMS with a low water/gypsum ratio could meet the actual production requirements. When compared with the PPSS, the SPMS had a lower water content and a higher dry density at the same water/gypsum ratios. When the water/gypsum ratio was low (e.g., 0.30), the SPMS exhibited more satisfactory moulding behaviour, greater absolutely dry compressive strength, and lower total porosity. In summary, this study presents a feasible method and viable theoretical guideline for the manufacture of PBG-based building materials with low water/gypsum ratios. | A novel method for preparing phosphorus building gypsum (PBG)-based building materials with low water/gypsum ratios | 10.1007/s10163-023-01595-x |
2023-03-01 | In this study, the CO 2 adsorption capacity was measured on Indonesian low-rank coals in the raw and dry conditions in powder and block states using different coal sample preparation to estimate CO 2 sequestration and storage potential. Coal sample specimens were taken from three different areas in the South Sumatra Basin, Indonesia. The adsorption experiments were performed using the volumetric method at a temperature of 318.15 K and pressure up to 3 MPa. The CO 2 excess adsorption capacity of powder coal is always higher than block coal. Moreover, decreasing moisture content by the drying process increases CO 2 adsorption capacity on coal. Based on fitted CO 2 adsorption experimental data with the Langmuir and Freundlich isotherm model, the adsorption occurs on monolayer and multilayer at various conditions. Langmuir volume capacity and pressure show drying and crushing process increased adsorption capacity. However, the drying process affects more the capability of coal to adsorb CO 2 than the powdered sample, especially in low-rank coal. It was also observed adsorption capacity is directly proportional to huminite content in the coal. Due to lower moisture and higher huminite contents, the dried WB coal powder had the highest CO 2 adsorption capacity over the other coal samples in similar sample conditions. Altogether, this study may provide a better understanding in CO 2 adsorption on low-rank coal with different coal sample preparation resulting in different CO 2 adsorption capacity. | Experimental measurements of CO2 adsorption on Indonesian low-rank coals under various conditions | 10.1007/s13202-022-01569-z |
2023-03-01 | This paper focuses on the theoretical and experimental phase behavior determination of polyvinylchloride/polycaprolactone (PVC/PCL) blend. For this aim, the capability of the compressible regular solution (CRS) model to predict the phase behavior of the PVC/PCL blend was evaluated. The extreme sensitivity of the CRS model to the solubility parameters of the blend components and the lack of a unique value for the solubility parameters of each polymer led to various phase behavior predictions from upper critical solution temperature to complete immiscibility. To verify the CRS model predictions, dilute solution viscometry (DSV), Fourier transform infrared and differential scanning calorimetry were employed. The last two showed complete miscibility, while different DSV criteria indicated partial miscibility, which were in contrast to the predictions made by the CRS model. Finally, the dynamic phase diagram of the PVC/PCL blend was determined via rheological measurements for the first time, suggesting lower critical solution temperature behavior with the critical point located at 195 °C. | Evaluation of the compressible regular solution model predictions via rheologically determined phase diagram for polyvinylchloride/polycaprolactone blend | 10.1007/s00289-022-04212-3 |
2023-03-01 | The past five decades have witnessed satellite remote sensing become one of the most efficient tools for fire detection and estimating total burned areas. Not all algorithms are appropriate for detecting high-temperature events on a global scale. It is difficult for traditional fire detection algorithms to capture small and low-intensity fires with significant accuracy. For this, we propose an improved fire detection algorithm by considering channel 4 and 11 µm of MODIS data with two different thresholds for hot and cold seasons. Moreover, false alarm rejections caused by the edges of clouds are designed for this algorithm. The validation against 231 reference fires showed good performance of our algorithm over the northern forests of Iran. This algorithm detected 72 fires, while the MODIS fire product, a widely used source for fire detection, detected only 26 fires. The results indicate an outperformance of 19.91%. The results show that our algorithm for the fire detection method overperforms the traditional methods and can be particularly useful for fire detection in the northern forests of Iran and can be applied in similar forests worldwide. | An improved algorithm for small and low-intensity fire detection in the temperate deciduous forests using MODIS data: a preliminary study in the Caspian Forests of Northern Iran | 10.1007/s11069-022-05777-y |
2023-03-01 | High-quality microwave amplifiers and notch-filters can be made from microwave optomechanical systems in which a mechanical resonator is coupled to a microwave cavity by radiation pressure. These amplifiers and filters rely on optomechanically induced transparency (OMIT) and absorption (OMIA), respectively. Such devices can amplify microwave signals with large, controllable gain, high dynamic range and very low noise. Furthermore, extremely narrowband filters can be constructed with this technique. We briefly review previous measurements of microwave OMIT and OMIA before reporting our own measurements of these phenomena, which cover a larger parameter space than has been explored in previous works. In particular, we vary probe frequency, pump frequency, pumping scheme (red or blue), probe power, pump power and temperature. We find excellent agreement between our measurements and the predictions of input/output theory, thereby guiding further development of microwave devices based on nanomechanics. | Microwave Optomechanically Induced Transparency and Absorption Between 250 and 450 mK | 10.1007/s10909-022-02671-6 |
2023-03-01 | Rice production has soared globally because it is one of the most common staple foods. Consequently, there has been massive generation of the husk which could pose as environmental risk factor. To convert waste to wealth, rice husk ash was used as a supplement for cement to stabilize lateritic soil for low-cost roads. This study was to develop exponential models for predicting the strength properties of the stabilized lateritic soil. Constant dosages of cement 2, 4, 6 and 8% were mixed with variations of rice husk ash of 4, 8,12, 16, 20, 24 and 28%; all percentages were measured by weight of the dry lateritic soil. Preliminary tests were conducted on the natural lateritic soil for characterization. The clay minerals present in the lateritic soil were identified using X-ray diffraction technique, while the mineral oxide composition of rice husk ash was done using X-ray fluorescent technique. The tests carried out on the treated lateritic soil were consistency limits, compaction test (British Standard Light), California Bearing Ratio unconfined compressive strength and durability test. The lateritic soil was classified to be A-7(1) in the AASHTO rating system and Silty Sand (SM) in the Unified Soil Classification System. The predominant non-clay mineral and clay mineral present in the soil were quartz, montmorillonite and kaolinite with traces of garnet, and ilmenite. The consistency limits for the treated lateritic soil all reduced with increase in rice husk ash and cement contents. The optimum moisture content of the treated lateritic soil increased while the maximum dry density reduced with increase in rice husk ash content. The California bearing ratio and the unconfined compressive strength at 7-day curing period increased by 1616.67% and 420.37%, respectively, with the addition of up to 8% of cement and 28% of quarry rice husk ash contents. Exponential logarithmic models of good fit were developed for predicting California bearing ratio and unconfined compressive strength (7-day curing) for any given mix proportion of the stabilized soil. The correlation coefficient and coefficient of determination were 0.972 and 0.945, respectively, for California bearing ratio while that of unconfined compressive strength (7-day curing) were 0.985 and 0.971, respectively. At 95% confidence level, optimum moisture content, rice husk ash content and cement content were all significant in predicting California bearing ratio and unconfined compressive strength (7-day curing). | Exponential Logarithmic Models for Strength Properties of Lateritic Soil Treated with Cement and Rice Husk Ash as Pavement of Low-Cost Roads | 10.1007/s42947-021-00134-x |
2023-03-01 | A method of ranking the work of ductile crack propagation ( a p ) and critical brittleness temperature ( T 50 ) was used to analyze the influence of ferrite grain size, pearlite and sulfide (sulfur) content, as well as hardness and concentration of phosphorus on the behavior and rate of T 50 and a p change. The studies were carried out using the ductile-brittle transition criterion, according to which such transition is controlled by the size ratio of elementary microcracks of a brittle transcrystalline cleavage (Λ b ) and ductile (dimple) fracture (Λ d ). A correlation analysis procedure was used to study the influence of the grain size of ferrite, volumetric fraction of pearlite, amounts of sulfur and phosphorus, as well as the yield strength on the critical brittleness temperature ( T 50 ). The same procedure was used to study the effect of sulfur content, pearlite volumetric fraction, as well as ferrite hardness ( HV 10 ) and grain size on the work of ductile crack propagation in low-carbon steel. It was shown that the values of T 50 and a p are closely related to each other through the size of an elementary microcrack (dimple) during ductile fracture. | Influence of Chemical Composition and Structure on Characteristics of Cold Resistance and Impact Strength of Low-Carbon Steel | 10.1007/s11015-023-01468-6 |
2023-03-01 | The influence of heat treatment, simulating thermal cycles and welding in the process of manufacturing joint fittings on microstructure, strengthening phase precipitation, and mechanical properties of base metal and near-weld zone of fittings, made of low-carbon copper-containing steel, is studied. Rolled product specimens are produced under laboratory and industrial conditions. Heat treatment regimes are developed, and mechanical properties of pipeline fittings of strength class K60 (X70) after normalizing with tempering and strength class K65 (X80) after additional quenching before tempering combined with satisfactory impact strength and weldability are provided. | Structure and Properties of Weldable Precipitation-Hardening Steel Alloyed with Copper for High-Strength Pipeline Fittings | 10.1007/s11015-023-01466-8 |
2023-03-01 | Large parts of southern Africa are influenced by extra-tropical weather systems for most of the year. During late summer (December–March), the circulation over the area becomes distinctly tropical. This paper introduces the Africáne, a synoptic scale tropical low-pressure system which has been shown to cause widespread and heavy rainfall over the southern sub-continent of Africa. The frequency of occurrence of Africánes, their contribution to rainfall and interannual variability are discussed in this paper. Africánes occur most frequently at the longitude of the Caprivi area with a second peak in frequency at around 32.5° E. They mostly occur over Namibia, Botswana and Zimbabwe and only infrequently infiltrate as far south as the borders of South Africa. However, when they do occur over South Africa, they cause widespread heavy rainfall and floods. Rainfall is mostly confined to the eastern flank of Africánes and between 20 and 35% of the annual rainfall over southern Africa in late summer can be attributed to these systems. There are two main synoptic regimes associated with Africánes: a westerly wave or tropical-temperature trough combines with the Africáne to pull rainfall southwards into South Africa. The second, is a mid-level subtropical high pressure, located south of the Africáne, which causes the rainfall to be confined to the north. The interannual variability of Africánes are closely linked to rainfall over southern Africa, such that an above normal number of Africánes in a season causes above normal rainfall over southern Africa. The number of Africánes that form per year is linked to El Niño–Southern Oscillation (ENSO). It is recommended that the predictability of Africánes on different time scales should be investigated. | Africánes in southern Africa: attributes and contribution to rainfall of a continental tropical low | 10.1007/s00382-022-06380-4 |
2023-03-01 | This research article presents the competency of the nanoparticle-incorporated low-fume welding electrode in terms of the mechanical and metallurgical properties. The superior mechanical and metallurgical quality of the welds developed by the experimental electrodes adds to the specific highlight of the present work, which is due to the increase in percentage recovery of the primary elements in the weld. Various mechanical tests such as tensile test, impact test and hardness test were carried out in the weldment and is correlated with the microstructure study. Critical weld parameter for the weld deposit was also compared and verified with respect to the hardness and tensile test values for the weld deposits and found to be in good agreement. | Investigations on the weld metal properties of nanoparticle-embedded low-fume SMAW electrodes | 10.1007/s12666-022-02700-8 |
2023-03-01 | Abstract The influence of a dispersed filler located between the layers of a continuous reinforcing filler has been studied on the characteristic of residual compressive strength after impact of carbon fiber reinforced polymer based on SYT-49S high-strength carbon tow filler (People’s Republic of China) and VSE‑1212 epoxy matrix. Microstructural studies of the powders of various nature have been presented (the particle sizes have been determined, and the microstructure of these powders has been given) used as a dispersed filler. The following have been presented and analyzed: diagrams obtained as a result of a low-speed impact and C-scans of nondestructive ultrasonic testing after impact of the carbon fiber samples, as well as the results of compression after impact for these carbon fiber samples. | A Comparative Assessment of the Influence of Modification with Thermoplastic Powders on the Residual Compressive Strength of the Carbon Fiber Reinforced Polymers | 10.1134/S1995421223010100 |
2023-03-01 | Leaf nitrogen (N) level affects not only photosynthetic CO 2 assimilation, but also two photosystems of the photosynthetic electron transport. The quantum yield of photosystem II [Y(II)] and the non-photochemical yield due to the donor side limitation of photosystem I [Y(ND)], which denotes the fraction of oxidized P700 (P700 + ) to total P700, oppositely change depending on leaf N level, and the negative correlation between these two parameters has been reported in leaves of plants cultivated at various N levels in growth chambers. Here, we aimed to clarify whether this correlation is maintained after short-term changes in leaf N level, and what parameters are the most responsive to the changes in leaf N level under field conditions. We cultivated rice varieties at two N fertilization levels in paddy fields, treated additional N fertilization to plants grown at low N, and measured parameters of two photosystems of mature leaves. In rice leaves under low N condition, the Y(ND) increased and the photosynthetic linear electron flow was suppressed. In this situation, the accumulation of P700 + can function as excess energy dissipation. After the N addition, both Y(ND) and Y(II) changed, and the negative correlation between them was maintained. We used a newly-developed device to assess the photosystems. This device detected the similar changes in Y(ND) after the N addition, and the negative correlation between Y(ND) and photosynthetic O 2 evolution rates was observed in plants under various N conditions. This study has provided strong field evidence that the Y(ND) largely changes depending on leaf N level, and that the Y(II) and Y(ND) are negatively correlated with each other irrespective of leaf N level, varieties and annual variation. The Y(ND) can stably monitor the leaf N status and the linear electron flow under field conditions. | Tight relationship between two photosystems is robust in rice leaves under various nitrogen conditions | 10.1007/s10265-022-01431-7 |
2023-03-01 | Although the partial nitrification-anammox process (PN-A) has achieved great success in nitrogen removal for the high ammonium concentration wastewater, its application is still limited in low ammonium concentration wastewater treatment due to its instability and low nitrogen removal efficiency. In this study, a sequencing batch reactor (SBR) with continuous aeration was employed to enrich ammonia oxidation bacteria (AOB) and suppress nitrite oxidation bacteria (NOB) first; then, the SBR was operated intermittently aerated SBR (IASBR), to which the anammox granular sludge (AMX) was added to achieve complete autotrophic nitrogen removal under low influent ammonium concentration of 100 mg/L. A mathematical model was used to optimize the IASBR aeration strategy to achieve sub-optimal nitrogen removal. The experimental results showed that high nitrite accumulation efficiency (above 80%) in the SBR and a fast start-up within 100 days and a stable TN (total nitrogen) removal efficiency of 70% were achieved in the IASBR. Meanwhile, the simulation results indicated that keeping aeration duration at 4 h, k L a (oxygen transfer coefficient) at 50 day −1 , or aeration duration at 2.5 h, k L a at 80 day −1 could obtain a higher total nitrogen removal efficiency (TNR) (TNR > 80%), and the TN removal could also be improved by increasing hydraulic retention time (HRT) under the optimal oxygen supply rate. Graphical Abstract | Start-up and optimization of a one-stage partial nitrification-anammox (PN-A) process treating low ammonium concentration wastewater: experimental results and modeling investigation | 10.1007/s11356-022-24526-z |
2023-03-01 | Yttria-stabilized zirconia (YSZ) deposition at short spray distance is of great interest for the aeronautic industry, especially to perform a thermal barrier coating (TBC) local repair. Typical thermal spray techniques usually employed to deposit such coatings are not designed for this type of application due to the powers involved. This work focuses on a plasma torch operating at atmospheric pressure, at low power (< 1 kW) and at short spray distance (4 mm). Precursor solutions are directly injected in the plasma afterglow to be sprayed and deposited onto a substrate. During flight time, precursor conversion is initiated. However, because of the low afterglow temperature (600 °C), droplets are not fully converted into YSZ when they impact the substrate. Typically, posttreatment is applied to improve the conversion of precursors into oxides, but this operation is very time- and therefore money-consuming. This study is focused on exploring a way to maximize the heat transfer to droplets already deposited by generating exothermicity using a redox reaction between zirconium and yttrium nitrates with ammonium acetate. This work highlights how exothermic precursor decomposition reactions as well as the gel-like consistency of the deposited clusters can improve both chemical conversion and coating microstructure. | Impact of Precursor Thermal Decomposition Reactions on YSZ Coatings Deposited with a Low-Power Plasma Torch at Short Spray Distance | 10.1007/s11666-022-01510-0 |
2023-03-01 | Cold tolerance at germination and seedling stage is one of the most seeked traits in Southern Brazilian rice ( Oryza sativa L.) cultivars, thus, the availability of improved methods for germplasm assessment is of high importance for breeding programs. The aim of this study was to validate an optimized Average Tolerance Index (ATI) for rice germplasm assessment under cold at germination and early seedling stage. A diverse panel composed by 124 rice accessions was assayed. Four genotypes with known performance under cold were used as controls (two tolerant and two sensitive). The genotypes were sown in roll papers, and evaluated at 13 °C for 28 days (cold stress) and 25 °C for seven days (control). Four traits were measured, germination percentage, coleoptile length, root length and shoot length, which were converted in terms of relative performance (cold/control). A PCA analysis was carried out. The ATI was calculated as a linear combination of all trait’s relative performance, weighted by the importance of each trait in explaining the genetic variability in the set, through including the PC1 vectors as trait coefficients. K means was applied for genotype classification. The panel showed expressive genetic variability for performance under low temperature. The ATI successfully distinguished the controls regarding their cold tolerance and allowed the formation of four classes of genotypes, sensitive, moderately sensitive, moderately tolerant and tolerant. The assessment of rice germplasm for cold tolerance at germination and seedling stage through ATI is a viable alternative for the identification of tolerant genotypes. | An optimized index for cold tolerance assessment in rice during germination and early seedling stage | 10.1007/s12892-022-00175-z |
2023-03-01 | Abstract A model has been developed that describes the grain growth upon austenitization, taking into account the pinning of moving grain boundaries by carbonitride precipitates. The behavior of these precipitates is described using our previously developed approach for predicting the evolution of carbonitride particles. The software implementation of the model was carried out, and numerical calculations were performed. The calculation results have been compared with the experimental data in the literature and their good agreement is shown. | Simulation of Austenite Grain Growth in Low-Alloyed Steels upon Austenitization | 10.1134/S0031918X23600100 |
2023-03-01 | Low methoxyl pectin was conjugated to gelatin by Maillard reaction in aqueous media at pH 7 and 90 °C. The objective of wet-conjugation was to improve the properties and stability of complex coacervates. The change in the browning index, grafting degree, and protein structure and particle size confirmed the conjugation of gelatin to low methoxyl pectin. Conjugation shifted the coacervation pH from 4.3 to 4.8 while the coacervation yield decreased from 64.3% to 43.7% at P < 0.05. Conjugation for 1 h decreased the interfacial tension value from 24.7 ± 0.2 Nm to 20.4 ± 0.3 Nm/m. On the other hand, heating for 2 h and 3 h increased the interfacial tension to 26.5 ± 0.6 and 28.6 ± 0.8 Nm/m, respectively. Conjugation for 1 h increased the binding affinity of cinnamaldehyde to gelatin while extended heating showed negative results. Properties of microcapsules were most improved for gelatin-low methoxyl pectin conjugated for 1 h. Microcapsules formed by conjugates with 1 h reaction time showed an encapsulation efficiency of 90.6% and an average particle size of 44.2 µm. The encapsulation efficiency decreased up to 70.7%, while the average particle size increased to 62.2 µm with a high reaction time at P < 0.05. Conjugation significantly improved the stability of microcapsules at pH (3, 5, 7, and 9) and ionic strength (100–300 mM) at P < 0.05. However, high ionic strength and pH variation completely suppressed the complex coacervation of biopolymer mixture. Findings revealed that initiation of wet-conjugation by Maillard reaction could be an ideal approach to improve the stability of complex coacervates. Graphical Abstract | Conjugation Induced by Wet-Heating of Gelatin and Low Methoxyl Pectin Improves the Properties and Stability of Microcapsules Prepared by Complex Coacervation | 10.1007/s11483-022-09754-7 |
2023-03-01 | Low pressure drop is highly desirable for respiratory filters. Surface activation plays an important role to enhance the filtration performance of respiratory filters. In this study, a three-layer composite respiratory filter was developed using a combination of polypropylene (PP) nonwoven layers and chitosan nanofibres (CSNF) with variable coating time (h) during the electrospinning process. To study the impact of surface activation on filtration performance, the outer surface of all the samples were modified using low-pressure plasma treatment. Filtration performance testing was conducted to determine the filtration efficiency (%), pressure drop (Pa), and quality factor (Q) results, before and after the surface treatment. The maximum values of filtration efficiency and quality factor achieved were 99.99% and 0.068, respectively. The lowest value of the pressure drop was 16.12 Pa. All the low-pressure plasma-treated samples showed higher filtration efficiency and quality factor compared to untreated samples due to a more effective capturing mechanism. However, pressure drop results indicated no significant difference. Furthermore, the decay of plasma treatment impact was analysed by using drop shape analysis method to measure the water contact angle on the surface of the samples. Results showed a gradual decrease in surface modification impact and the surface of the treated samples changed from hydrophilic to hydrophobic with the passage of time. | Effect of Low-Pressure Plasma Surface Modification on Filtration Performance of Chitosan Nanofibrous Respiratory Filter | 10.1007/s12221-023-00029-7 |
2023-03-01 | Purpose Climate change is a global threat, and inhalational anesthetics contribute to global warming by altering the photophysical properties of the atmosphere. On a global perspective, there is a fundamental need to reduce perioperative morbidity and mortality and to provide safe anesthesia. Thus, inhalational anesthetics will remain a significant source of emissions in the foreseeable future. It is, therefore, necessary to develop and implement strategies to minimize the consumption of inhalational anesthetics to reduce the ecological footprint of inhalational anesthesia. Source We have integrated recent findings concerning climate change, characteristics of established inhalational anesthetics, complex simulative calculations, and clinical expertise to propose a practical and safe strategy to practice ecologically responsible anesthesia using inhalational anesthetics. Principal findings Comparing the global warming potential of inhalational anesthetics, desflurane is about 20 times more potent than sevoflurane and five times more potent than isoflurane. Balanced anesthesia using low or minimal fresh gas flow (≤ 1 L·min -1 ) during the wash-in period and metabolic fresh gas flow (0.35 L·min -1 ) during steady-state maintenance reduces CO 2 emissions and costs by approximately 50%. Total intravenous anesthesia and locoregional anesthesia represent further options for lowering greenhouse gas emissions. Conclusion Responsible anesthetic management choices should prioritize patient safety and consider all available options. If inhalational anesthesia is chosen, the use of minimal or metabolic fresh gas flow reduces the consumption of inhalational anesthetics significantly. Nitrous oxide should be avoided entirely as it contributes to depletion of the ozone layer, and desflurane should only be used in justified exceptional cases. Objectif Les changements climatiques constituent une menace mondiale et les anesthésiques volatils contribuent au réchauffement climatique en modifiant les propriétés photophysiques de l’atmosphère. Dans une perspective mondiale, il est fondamentalement nécessaire de réduire la morbidité et la mortalité périopératoires et de procurer une anesthésie sécuritaire. Par conséquent, les agents volatils demeureront une source importante d’émissions dans un avenir proche. Il est donc nécessaire d’élaborer et de mettre en œuvre des stratégies pour minimiser la consommation d’anesthésiques volatils afin de réduire l’empreinte écologique de l’anesthésie par inhalation. Sources Nous avons intégré les découvertes récentes concernant les changements climatiques, les caractéristiques des anesthésiques volatils connus, des calculs de simulation complexes et l’expertise clinique pour proposer une stratégie pratique et sécuritaire pour exercer une anesthésie écologiquement responsable en utilisant des anesthésiques volatils. Constatations principales En comparant le potentiel de réchauffement planétaire des anesthésiques volatils, le desflurane est environ 20 fois plus puissant que le sévoflurane et cinq fois plus puissant que l’isoflurane. Une anesthésie équilibrée avec un débit de gaz frais faible ou minimal (≤ 1 L·min -1 ) pendant la période de mise en route (‘wash-in’) et le débit métabolique de gaz frais (0,35 L·min -1 ) pendant le maintien à l’état d’équilibre réduit le CO 2 et les coûts d’environ 50 %. L’anesthésie intraveineuse totale et l’anesthésie locorégionale représentent d’autres options pour réduire les émissions de gaz à effet de serre. Conclusion Les choix responsables en matière de prise en charge anesthésique devraient accorder la priorité à la sécurité des patients et à l’évaluation de toutes les options disponibles. Si l’anesthésie par inhalation est choisie, l’utilisation d’un débit minimal ou métabolique de gaz frais réduit considérablement la consommation d’anesthésiques volatils. Le protoxyde d’azote doit être complètement évité car il contribue à l’appauvrissement de la couche d’ozone, et le desflurane ne doit être utilisé que dans les cas exceptionnels et justifiés. | A call for immediate climate action in anesthesiology: routine use of minimal or metabolic fresh gas flow reduces our ecological footprint | 10.1007/s12630-022-02393-z |
2023-03-01 | Lower extremity robotic exoskeletons (LEEX) can not only improve the ability of the human body but also provide healing treatment for people with lower extremity dysfunction. There are a wide range of application needs and development prospects in the military, industry, medical treatment, consumption and other fields, which has aroused widespread concern in society. This paper attempts to review LEEX technical development. First, the history of LEEX is briefly traced. Second, based on existing research, LEEX is classified according to auxiliary body parts, structural forms, functions and fields, and typical LEEX prototypes and products are introduced. Then, the latest key technologies are analyzed and summarized, and the research contents, such as bionic structure and driving characteristics, human–robot interaction (HRI) and intent-awareness, intelligent control strategy, and evaluation method of power-assisted walking efficiency, are described in detail. Finally, existing LEEX problems and challenges are analyzed, a future development trend is proposed, and a multidisciplinary development direction of the key technology is provided. | Systematic Review on Wearable Lower Extremity Robotic Exoskeletons for Assisted Locomotion | 10.1007/s42235-022-00289-8 |
2023-03-01 | An extremely heavy rainfall event lasting from 17 to 22 July 2021 occurred in Henan Province of China, with accumulated precipitation of more than 1000 mm over a 6-day period that exceeded its mean annual precipitation. The present study examines the roles of persistent low-level jets (LLJs) in maintaining the precipitation using surface station observations and reanalysis datasets. The LLJs triggered strong ascending motions and carried moisture mainly from the outflow of Typhoon In-fa (2021). The varying directions of the LLJs well corresponded to the meridional shifts of the rainfall. The precipitation rate reached a maximum during 20–21 July as the LLJs strengthened and expanded vertically into double LLJs, including synoptic-weather-system-related LLJs (SLLJs) at 850–700 hPa and boundary-layer jets (BLJs) at ∼950 hPa. The coupling of the SLLJ and BLJ provided strong mid- and low-level convergence on 20 July, whereas the SLLJ produced mid-level divergence at its entrance that coupled with low-level convergence at the terminus of the BLJ on 21 July. The formation mechanisms of the two types of LLJs are further examined. The SLLJs and the low-pressure vortex (or inverted trough) varied synchronously as a whole and were affected by the southwestward movement of the WPSH in the rainiest period. The persistent large total pressure gradient force at low levels also maintained the strength of low-level geostrophic winds, thus sustaining the BLJs on the synoptic scale. The results based on a Du-Rotunno 1D model show that the Blackadar and Holton mechanisms jointly governed the BLJ dynamics on the diurnal scale. 2021 年 7 月 17 日至 23 日, 中国河南省发生了一次持续性极端暴雨事件, 六天的累积降水量超过 1000 mm, 超过其年平均降水量. 本文利用常规观测资料和再分析数据, 探究了持续性低空急流对降水维持的影响机制. 低空急流出口区产生强上升运动, 并输送大量主要来自台风 “烟花” (2021) 外围的水汽. 低空急流的方向变化与降水落区的经向移动密切相关, 在7月 20–21 日, 低空急流显著加强, 并垂直厚度加深从而形成 “双低空急流”, 即包括与天气系统相关位于 850–950 hPa 的天气尺度急流 (SLLJ) 和位于 950 hPa 左右的边界层急流 (BLJ), 此时降水也达到最强. 其中在 7 月 20 日, SLLJ 和 BLJ 的正涡度区和出口区分别产生中层和低层辐合, 而在 7 月 21 日, SLLJ 北移, 其入口区辐散与 BLJ 出口区辐合发生耦合, 有利于降水的持续. 本文进一步研究了这两类低空急流的形成机制. SLLJ 与低涡 (以及后来发展为倒槽) 是同时发生变化的耦合系统, 在降水最强的阶段受到副高西南移动的影响而加强. 天气尺度上这种持续较大的气压梯度力也维持了低层强地转风, 从而在天气尺度上使 BLJ 得以维持, 而在日变化尺度上, 根据低空急流一维解析模型, BLJ 的日变化同时受到 Blackadar 机制和 Holton 机制的共同影响. | The Roles of Low-level Jets in “21·7” Henan Extremely Persistent Heavy Rainfall Event | 10.1007/s00376-022-2026-1 |
2023-03-01 | The inhibitory performance of quince extract (QE) on the corrosion and electrochemical properties of low-carbon steel in 1 molar hydrochloric acid was studied by electrochemical methods and weight loss measurement. The chemical compounds contained in quince that offer substantial corrosion inhibition impacts (e.g., amino acids and flavonoids) were examined by Fourier-transform infrared spectroscopy and ultraviolet. Polarization tests and electrochemical impedance spectroscopy results showed that increasing the concentration of the extract in the range of 200–1200 ppm increased its inhibition efficiency. The highest inhibition efficiency of the extract based on polarization and EIS results was respectively 95% and 93.0%, both observed at a concentration of 1200 ppm. Based on the results, quince extract was considered as a mixed-type corrosion inhibitor. Scanning electron microscopy and atomic force microscopy of the surface of steel specimens immersed in 1 M HCl without and with 200–1200 ppm of the inhibitor showed the effectiveness of quince extract in preventing corrosion. Graphical Abstract | Corrosion and Electrochemical Characterization of St37 in the Presence of Quince Extract as a Green and Sustainable Inhibitor | 10.1007/s12678-022-00788-6 |
2023-03-01 | Due to its high analysis speed and acceptable accuracy, the Spark Atomic Emission Spectroscopy method has been used widely in steel production factories. Since the accuracy of the results dramatically impacts the quality of the final product, the measurement uncertainty must be calculated and presented along with the analysis results. The primary purpose of this paper is to present a method for estimating the measurement uncertainty of carbon determination in carbon and low alloy steel by spark atomic emission spectroscopy. After identifying the factors influencing the test results, we presented a method for quantification and calculation of each source contribution to the combined uncertainty using mathematical and statistical methods. Finally, the amount of expanded uncertainty is determined for a 95% of confidence level. It was found that the measurement uncertainty is mainly affected by the calibration curve, while the analyst error has no significant effect on the measurement uncertainty. The extended relative uncertainty of 0.01 was determined at the 95% confidence level with a coverage factor k = 2. Graphical Abstract | A method for estimating the measurement uncertainty of carbon determination in low carbon and low alloy steels by spark atomic emission spectroscopy | 10.1007/s44211-022-00264-7 |
2023-03-01 | The paper presents the results of a study of the homogeneity of the thickness of the modified layer on the surface of a toothed crown made of structural steel 38Cr2MoAl with a tooth modulus m = 0.5 and the number of teeth 14, obtained as a result of ion-plasma nitriding in a beam-plasma formation generated in a stationary and pulse-periodic non-self-sustained glow discharge with a hollow cathode at low, about 1 Pa, pressure. The thicknesses of the nitrided layer at the top and at the base of the tooth obtained at the discharge pulse filling factors γ = 100, 85, and 50% are compared. It is shown that the minimum difference in the thicknesses of the nitrided layer, which is about 6%, is characteristic of the regime with a discharge pulse filling factor γ = 85%. Gas beam-plasma formations formed at low pressure are promising in the processes of ion-plasma nitriding of parts of complex shape. | Features of Nitriding of the Surface of a Small-Modulus Toothed Crown in Pulsed-Periodic Gas Beam-Plasma Formation at Low Pressure | 10.1007/s11182-023-02838-y |
2023-03-01 | In this study, a five-factorial central composite design was employed to optimize pectin extraction from novel source, through ultrasound-assisted extraction. A 35.58% yield was obtained under optimized conditions of pH 1.0, solid (g): liquid (mL) ratio 1:24, amplitude 84.2 Hz, duty cycle 23 s/30 s, and time 30 min. The equivalent weight, methoxyl content, anhydrouronic acid content, degree of esterification, water-holding capacity, and oil-holding capacity of the extracted pectin were 796.40 ± 2.07, 8.29 ± 0.38%, 71.32 ± 0.54%, 64.66 ± 2.08%, 8.04 ± 0.10 g water/g pectin, and 2.24 ± 030 g oil/g pectin, respectively. The chemical profile of the extracted pectin was assessed with FTIR and NMR analyses. The extracted pectin was utilized as a butter substitute in cookies. Up to 30% butter in cookies could be replaced with the extracted pectin without altering the sensory and physicochemical properties. Overall, results of presented work suggest that using waste-derived pectin as a fat substitute in cookies offers a sustainable and health-promoting approach for converting waste into wealth. | Sustainable utilization of Citrus limetta peel for obtaining pectin and its application in cookies as a fat replacer | 10.1007/s13197-022-05424-1 |
2023-03-01 | Abstract Neodecanoic acid diamides were prepared by a simple one-step procedure involving condensation of neodecanoic acid with diethylenetriamine, triethylenetetramine, and pentaethylenehexamine. The inhibiting effect of these diamides on the corrosion of St3 low-carbon steel in 2 М H 2 SO 4 and in 1 and 5 М HCl was studied gravimetrically. All the compounds synthesized efficiently inhibit the steel corrosion with the degree of protection at room temperature of 94–95% in 2 М H 2 SO 4 and 96–97% in 1 М HCl. | Neodecanoic Acid Diamides as Inhibitors of Acid Corrosion of Low-Carbon Steel | 10.1134/S1070427223030084 |
2023-03-01 | Rationale Conditions with sustained low-grade inflammation have high comorbidity with depression and anxiety and are associated with social withdrawal. The basolateral amygdala (BLA) is critical for affective and social behaviors and is sensitive to inflammatory challenges. Large systemic doses of lipopolysaccharide (LPS) initiate peripheral inflammation, increase BLA neuronal activity, and disrupt social and affective measures in rodents. However, LPS doses commonly used in behavioral studies are high enough to evoke sickness syndrome, which can confound interpretation of amygdala-associated behaviors. Objectives and methods The objectives of this study were to find a LPS dose that triggers mild peripheral inflammation but not observable sickness syndrome in adult male rats, to test the effects of sustained mild inflammation on BLA and social behaviors. To accomplish this, we administered single doses of LPS (0–100 μg/kg, intraperitoneally) and measured open field behavior, or repeated LPS (5 μg/kg, 3 consecutive days), and measured BLA neuronal firing, social interaction, and elevated plus maze behavior. Results Repeated low-dose LPS decreased BLA neuron firing rate but increased the total number of active BLA neurons. Repeated low-dose LPS also caused early disengagement during social bouts and less anogenital investigation and an overall pattern of heightened social caution associated with reduced gain of social familiarity over the course of a social session. Conclusions These results provide evidence for parallel shifts in social interaction and amygdala activity caused by prolonged mild inflammation. This effect of inflammation may contribute to social symptoms associated with comorbid depression and chronic inflammatory conditions. | Liposaccharide-induced sustained mild inflammation fragments social behavior and alters basolateral amygdala activity | 10.1007/s00213-023-06308-8 |
2023-03-01 | Feasibility of waste-to-energy (WtE) incineration in municipal solid waste (MSW) management is hindered by low lower heating value $$(LHV)$$ ( L H V ) . This paper seeks to evaluate the characteristics of MSW of Dhaka City to understand the $$LHV$$ LHV and its changing trend over time through the development and application of an empirical model. 90 datasets were prepared comprising percentage of waste components from extensive characterization surveys in two different seasons between 2017 and 2018 following standard field and laboratory protocols. Three reference equations were used to find $$LHV$$ LHV of each dataset and average of them was used as dependent variable where the components were used as explanatory variables to develop regression model. Model shows waste from markets, offices and landfills meet the threshold $$(\ge 6\mathrm{ MJ}/\mathrm{kg})$$ ( ≥ 6 MJ / kg ) for WtE incineration. Household waste (i.e., > 60%) may be incinerated by mixing office and market waste. Restaurant waste due to high moisture (> 74%) is suggestive to anaerobic digestion. Street wastes are to be avoided from incineration for high sand content (28.7%). Changes of $$LHV$$ LHV over time have been predicted from previously studied data. This paper discusses that different scenarios (e.g., moisture reduction, selection of specific areas, and time changes) can maximize $$LHV$$ LHV to make WtE incineration theoretically feasible. | Developing empirical model for heating value of MSW to assess waste-to-energy incineration feasibility: study in Dhaka city | 10.1007/s10163-022-01481-y |
2023-03-01 | The present work aimed at the evaluation of mulberry ( Morus nigra L.) fruit extracts-doped hybrid sol–gel coatings’ corrosion resistance performance for low carbon steel in NaCl electrolyte. Alkoxysilane formulation was prepared to utilize 3-glycidoxypropyltrimethoxysilane and tetraethyl orthosilicate precursors. The corrosion inhibitive properties of extracts-doped composite coatings on low carbon steel surface in NaCl electrolyte were determined by exploiting electrochemical impedance spectroscopy, electrochemical noise measurement and potentiodynamic polarization. The corrosion inhibition efficiencies obtained were 85.57% and 81.37% for hybrid coatings doped with mulberry ethanol extract and water extract, respectively. It was noted that the hybrid silanol film applied low carbon steel which was doped with 750 ppm mulberry ethanol extract rendered higher corrosion resistance. Additionally, the Tafel slopes indicated that mulberry extracts function as “mixed type” corrosion inhibitors, particularly prevailing cathodic inhibition. Surface characteristics of coated low carbon steel plates were researched engaging scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and wettability measurement. Fourier transform infrared spectroscopy established Fe–O–Si bonding among mild steel substrate and composite coating. Scanning electron micrographs affirmed that the coating provided better corrosion mitigation due to the inhibitive efficacy of the doping. Wettability analysis revealed that low carbon steel treated with 750 ppm mulberry ethanol extract doped coating was highly hydrophobic. Graphical abstract Developed films were coated on low carbon steel by self-assembled monolayer method. i corr values of composite coatings were significantly lower than the uncoated substrate. Mulberry extracts-doped-composite coatings revealed higher charge transfer resistance. Mulberry extracts-doped composite coatings demonstrated improved hydrophobicity. | Corrosion-resistant mulberry fruit (Morus nigra L.) extracts incorporated hybrid (GPTMS-TEOS) composite silanol coatings for low carbon steel protection | 10.1007/s10971-022-05993-9 |
2023-03-01 | Purpose High energy photon source is a 6 GeV diffraction-limited storage ring light source currently under construction in Beijing. A low-frequency fundamental radio-frequency (rf) system of 166.6 MHz was proposed to accommodate the accelerator physics design. Superconducting rf (srf) technologies were chosen for the storage ring rf accompanied by solid-state power amplifiers and digital low-level rf controls. The design of the rf system was completed, and the parameters are frozen. Elucidation of the rf design with key parameters is desired. Methods The requirements from the accelerator physics design will be presented followed by the detailed rf design. The logic behind the choice of key rf parameters is elaborated. The configuration of the entire rf system is presented. Results and conclusions The fundamental srf cavity of 166.6 MHz was designed to accelerate the ultrarelativistic electron beam. Heavy damping of higher-order modes in these cavities is required to avoid the coupled bunch instabilities. An active third harmonic srf of 499.8 MHz was adopted to realize the required rf gymnastics. Normal-conducting 5-cell cavities will be used for the booster rf. Solid-state amplifiers of 2.4 MW in total will be installed at HEPS to drive these cavities in the booster and the storage ring. A digital low-level rf system will be used to regulate rf field inside each cavity with high stabilities. The rf configuration during the commissioning and the operation scenarios are also presented. | Radio-frequency system of the high energy photon source | 10.1007/s41605-022-00366-w |
2023-03-01 | In our minimized follow-up trial with 137 participants with chronic low back pain, one group of participants received regular outpatient care, and the other group received balneotherapy by immersion in 42℃ thermal-mineral water in addition to regular outpatient care on 15 occasions for 3 weeks. Pain on movement and at rest on the 0–100 mm visual analogue scale (VAS), Oswestry index, the number of participants evaluating the symptoms clinically acceptable (Patient Acceptable Symptom State, PASS) and the EuroQol-5D-5L (EQ-5D-5L) quality of life questionnaire were assessed at basal time (at week 0) and after balneotherapy (at weeks 3 and 12). The VAS pain scores, the Oswestry index, the EQ-5D-5L index and the EQ-VAS significantly improved in the balneotherapy group after treatment at week 3 ( p < 0.001) and week 12 ( p < 0.001) compared to baseline, with a significant between group difference at week 3 ( p < 0.001) and week 12 ( p < 0.001). The pain VAS score on movement was 66.82 ± 11.48, 26.69 ± 21.49, and 20.09 ± 23.29 in the balneotherapy group, and 63.67 ± 14.77, 67.35 ± 15.44, and 70.23 ± 18.26 in the control group at the consecutive visits. The PASS increased in both groups at week 3 and week 12 compared to the baseline, with a significant between-group difference at week 3 and week 12 for the balneotherapy group. Our results suggest the therapeutic efficacy of immersion in 42℃ thermal mineral water on chronic low back pain. ClinicalTrials.gov Identifier: NCT05342051. | The effects of immersion in 42℃ radon, natrium, calcium, bicarbonate content thermal-mineral water on chronic low back pain. Controlled, follow-up study | 10.1007/s00484-023-02433-3 |
2023-03-01 | Actual evapotranspiration ( ETa ) estimates at regional and river basin scales can assist water authorities with water allocation decisions in agriculture and the ecosystem. Remote sensing is cutting-edge technology as well as a robust tool for generating spatiotemporal variation of energy balance components over large areas. The objectives of this study were to: (a) estimate and generate fully distributed ETa maps by the “Mapping Evapo Transpiration at high Resolution with Internalized Calibration” (METRIC) in the Akarsu Irrigation Area ( A = 9495 ha) in the Eastern Mediterranean Region of Turkey, (b) compare ETa estimations with crop evapotranspiration (ETc) series acquired by FAO-56 methodology, i.e., “two-step approach” and (c) investigate the correlation between Kc obtained by the METRIC model and Normalized Difference Vegetation Index (NDVI) for some specific crop types. Landsat satellite imagery data with 30 m by 30 m spatial resolution and meteorological data of two ground stations (L8 and Adana) were used to estimate daily and monthly ETa by the METRIC model in the winter and summer seasons of 2020. Results showed acceptable agreement between ETa and ETc estimations. ETa maps reflected the changes in parallel with crop type variations over the study area in the summer and winter seasons of 2020. A strong and moderate correlation was found between Kc acquired by METRIC (ETrF) and NDVI ( r = 0.91 for Peanut1 and r = 0.55 for Corn1) in the summer season. Research results led us to conclude that remote sensing technologies could be applied to quantify the spatiotemporal dynamics of surface energy balance variables for irrigation and non-irrigation seasons. Moreover, ETa estimation by the METRIC model could be used over large-scale irrigation schemes in realizing rational irrigation scheduling efficiently and managing agricultural water more effectively. | Actual evapotranspiration estimation using METRIC model and Landsat satellite images over an irrigated field in the Eastern Mediterranean Region of Turkey | 10.1007/s42990-023-00099-y |
2023-03-01 | The phosphorus chemical industry is an important source of heavy metals in farmland. Vegetables grown on contaminated soil potentially impose adverse effects on human health. In this study, the pollution status and health risks of heavy metals in vegetables around a phosphorus chemical plant in Kaiyang County, Guizhou Province, southwestern China, were assessed, and the low-accumulation vegetables were screened by bioaccumulation factor (BAF) and cluster analysis. Results showed the average concentrations of Hg, As, Cd, Pb, Cr, Mn, Co, and Zn in vegetables were 0.015, 0.728 0.382, 0.227, 0.850, 27.227, 0.525, and 6.438 mg/kg, respectively. The single-factor pollution index showed that Cd was moderately polluted, and Cr, Hg, As, and Pb were slightly polluted. The Nemerow pollution index showed that the overall heavy metal pollution was classified as moderately polluted. The accumulation of heavy metals in different vegetables varied greatly, and chard, crown daisy, chayote, pumpkin, eggplant, white radish, sweet potato, carrot, and potato were selected as the low-accumulator vegetables. The consumption of all vegetables except chayote poses both carcinogenic and noncarcinogenic risks; among them, the consumption of sweet potato leaves has the highest health risks. The local population needs to adjust plantation structure and change dietary habits, and government should strengthen the management of phosphorus chemical plant pollution. | Health risk assessment of heavy metal exposure through vegetable consumption around a phosphorus chemical plant in the Kaiyang karst area, southwestern China | 10.1007/s11356-022-24662-6 |
2023-03-01 | Random Access Memory (RAM) refers to the main memory of a computer. For the central processor unit (CPU) to operate quickly and effectively, it stores operating system software, applications, and other data. Unfortunately, single event upset and other high-soft error problems plague standard static RAM (SRAMs) in aircraft applications (SEU). Many Radiation-Hardened-Based Designs (RHBD) and Radiation-Hardened-Polar Designs (RHPD), such as the 12T We-Quatro and twelve-transistor (12T) Dice SRAM cells, have been created to address the soft error issues. However, they consume more total and static power, as well as have more delay and area. In this article, an RHPD and RHBD 12T SRAM cell is proposed to reduce power dissipation and area overhead. Compared to RHPD, the RHBD 12T SRAM cell devours less total and static power, and RHPD cells have less delay. The proposed SRAM cell is implemented in the 32 × 32 array architecture. The power consumption of a 32 × 32 SRAM array with a 12T RHBD SRAM cell is 1.33mW, which is 10.1% less than a 32 × 32 SRAM array with a 12T RHPD SRAM array is 4.23mW. Cadence virtuoso 6.1.5 at 45 nm Generic Process Design Kit (GPDK) technology file is used to simulate the comparative analysis for the SRAM cell. | Low-Power SRAM Cell and Array Structure in Aerospace Applications: Single-Event Upset Impact Analysis | 10.1007/s11277-022-10084-7 |
2023-03-01 | The seafloor vector magnetometer is an effective tool for marine geomagnetic surveys and seafloor magnetotelluric (MT) detection. However, the noise, power consumption, cost, and volume characteristics of existing seafloor vector magnetometers are insufficient for practical use. Therefore, a low-noise, low-power-consumption seafloor vector magnetometer that can be used for data acquisition of deep-ocean geomagnetic vector components is developed and presented. A seafloor vector magnetometer mainly consists of a fluxgate sensor, data acquisition module, acoustic release module, glass sphere, frame, burn-wire release, and anchor. A new low-noise data acquisition module and a fluxgate sensor greatly reduce power consumption. Furthermore, compact size is achieved by integrating an acoustic telemetry module and replacing the acoustic release with an external burn-wire release. The new design and magnetometer characteristics reduce the volume of the instrument and the cost of hardware considerably, thereby improving the integrity and deployment efficiency of the equipment. Theoretically, it can operate for 90 days underwater at a maximum depth of 6 000 m. The seafloor vector magnetometer was tested in the South China Sea and the Philippine Sea and obtained high-quality geomagnetic data. The deep-water environment facilitates magnetic field data measurements, and the magnetometer has an approximate noise level of 10 pT/rt (Hz)@1 Hz, a peak-to-peak value error of 0.2 nT, and approximate power consumption of 200 mW. The fluxgate sensor can measure the magnetic field in the lower frequency band and realize geomagnetic field measurements over prolonged periods. | Low-noise, low-power-consumption seafloor vector magnetometer | 10.1007/s00343-022-2105-2 |
2023-03-01 | The influence of structural characteristics on corrosion resistance of oilfield pipes of strength class K55– K60 made of steel grade 13CrV of two different industrial melts is investigated. It is shown that steels of similar melts, but different batches, may vary in level of corrosion resistance. Both a finer ferrite grain size and presence of tempered martensite and interfacial particles in the steel, the average size of which is about 1.9–2.1 nm, may lead to a reduction in corrosion resistance. At the same time, it is established that the density of such particles does not make a special contribution to reducing steel corrosion resistance. | Influence of Pipe Steel Structural Characteristics on Their Corrosion Resistance | 10.1007/s11015-023-01451-1 |
2023-03-01 | Several hypotheses try to explain the factors that limit the distribution of tree species in wetlands. Among them, the stress-gradient hypothesis states that interspecific ecological interactions (facilitation and competition) vary inversely across abiotic stress gradients, with facilitation being more common under conditions of high abiotic stress than under more benign conditions. We investigated the effects of ecological interactions on the biomass of two native tree species, Crateva tapia (highly flood-tolerant) and Hura crepitans (low flood tolerant) exposed to different experimental flooding conditions in a greenhouse. Individual and paired plants were submitted for 120 days to four treatments: (1) non-flooding and non-ecological interaction; (2) flooding and non-ecological interaction; (3) non-flooding and ecological interaction; (4): flooded and ecological interaction. Flooding reduced biomass allocation in H. crepitans. C. tapia biomass was reduced by interspecific interaction with H. crepitans . Flood and interspecific ecological interactions together facilitated the accumulation of biomass in H. crepitans . Our results support the stress-gradient hypothesis , showing that in a flooded environment, the species with low tolerance to flooding ( H. crepitans ) is favored by the presence of other species. Additional tests with other species can confirm whether this is a pattern that helps explain the establishment of tree species in wetlands. | Flooding affects plant–plant interactions in tree seedlings from fertile Amazonian floodplains, Brazil | 10.1007/s10750-022-04985-8 |
2023-03-01 | The assessment of marine environmental risk necessitates the simulation of a series of phenomena related to the risk as well as a measurement of creatures exposed to the risk. As a practical tool, the simulation is based on the establishment of a numerical ocean model. Although several decades have passed since the numerical model for ocean dynamics has been presented, there remains room for fundamental approaches to refine the method for computing solutions. This paper is a report of the development of a novel algorithm of the model. In this algorithm, discrete variables are positioned in a grid to maximally elicit the advantages of a numerical scheme adopted to each term in the governing equations and simplify the program structure. The implemented program is applied to a tidal flow and riverine buoyant plume in the Hinchinbrook Channel in the eastern coast of the Australian Continent. The computation reproduces the observed strong oscillatory flows and low-salinity water dynamics well. The proposed method is applicable to the movements of pollutants in regions of freshwater influence. | Ocean model with adjustable arrangements of discrete variables: application to strong tidal flows and low-salinity water dynamics | 10.1007/s00773-022-00920-7 |
2023-03-01 | Abstract Diarrhea is a global problem that causes economic losses in the pig industry. There is a growing attention on finding new alternatives to antibiotics to solve this problem. Hence, this study aimed to compare the prebiotic activity of low-molecular-weight hydrolyzed guar gum (GMPS) with commercial manno-oligosaccharide (MOS) and galacto-oligosaccharide (GOS). We further identified their combined effects along with probiotic Clostridium butyricum on regulating the intestinal microbiota of diarrheal piglet by in vitro fermentation. All the tested non-digestible carbohydrates (NDCs) showed favorable short-chain fatty acid-producing activity, and GOS and GMPS showed the highest production of lactate and butyrate, respectively. After 48 h of fermentation, the greatest enhancement in the abundance of Clostridium sensu stricto 1 was observed with the combination of GMPS and C. butyricum . Notably, all the selected NDCs significantly decreased the abundances of pathogenic bacteria genera Escherichia-Shigella and Fusobacterium and reduced the production of potentially toxic metabolites, including ammonia nitrogen, indole, and skatole. These findings demonstrated that by associating with the chemical structure, GMPS exhibited butyrogenic effects in stimulating the proliferation of C. butyricum . Thus, our results provided a theoretical foundation for further application of galactosyl and mannosyl NDCs in the livestock industry. Key points • Galactosyl and mannosyl NDCs showed selective prebiotic effects. • GMPS, GOS, and MOS reduced pathogenic bacteria and toxic metabolites production. • GMPS specifically enhanced the Clostridium sensu stricto 1 and butyrate production. Graphical Abstract | Butyrogenic effect of galactosyl and mannosyl carbohydrates and their regulation on piglet intestinal microbiota | 10.1007/s00253-023-12436-0 |
2023-03-01 | In southern Africa and elsewhere, the archaeological study of ceramics largely relies on two approaches that tend to be treated separately: technology and style. While the emphasis of Iron Age archaeology has been on the range of shapes and decorative characteristics of pots and how these are determined or illustrative of cultural identities, little is known about the technological processes of ceramic production. This article uses ethnoarchaeological methods to examine the chaine operatories of ceramic production in specific sociocultural contexts among the Nguni-speaking (Zulu) peoples in the Upper and Lower uThukela Basins in KwaZulu-Natal. The study focuses on social and technical decisions for ceramic production and documents production stages and attributes, design, style, and functional components. Moreover, the social characteristics of production stages are used to understand various techniques, processes, tools, and materials involved in ceramic production, including distribution and apprenticeship. The social and operational attributes of ceramic production discussed in this article are potential sources for developing models that would bridge the gaps between the technology and style approaches in the archaeological study of Iron Age ceramics in southern Africa. En Afrique australe et ailleurs, l'étude archéologique de la céramique s'appuie largement sur deux approches qui tendent à être traitées séparément: la technique et le style. Alors que l'archéologie de l'âge du fer a mis l'accent sur la gamme de formes et les caractéristiques décoratives des pots et sur la manière dont elles sont déterminées ou illustratives des identités culturelles, on sait peu de choses sur les processus technologiques de production de la céramique. Cet article utilise des méthodes ethnoarchéologiques pour examiner les chaînes opératoires de la production de céramique dans des contextes socioculturels spécifiques chez les peuples de langue nguni (zoulou) dans les bassins supérieur et inférieur d'uThukela au KwaZulu-Natal. L'étude se concentre sur les décisions sociales et techniques pour la production de céramique et documente les étapes de production et les attributs, la conception, le style et les composants fonctionnels. De plus, les caractéristiques sociales des étapes de production sont utilisées pour comprendre les différentes techniques, processus, outils et matériaux impliqués dans la production de céramique, y compris la distribution et l'apprentissage. Les attributs sociaux et opérationnels de la production de céramique discutés dans cet article sont des sources potentielles pour développer des modèles qui combleraient les écarts entre les approches technologiques et stylistiques dans l'étude archéologique de la céramique de l'âge du fer en Afrique australe. | Aspects of Zulu Ceramic Traditions in the Upper and Lower uThukela Basin, KwaZulu-Natal, South Africa | 10.1007/s10437-022-09510-9 |
2023-03-01 | The purpose of the study was to identify potential predictors of muscle hypertrophy responsiveness following neuromuscular electrical stimulation resistance training (NMES-RT) in persons with chronic spinal cord injury (SCI). Data for twenty individuals with motor complete SCI who completed twice weekly NMES-RT lasting 12–16 weeks as part of their participation in one of two separate clinical trials were pooled and retrospectively analyzed. Magnetic resonance imaging (MRI) was used to measure muscle cross-sectional area (CSA) of the whole thigh and knee extensor muscle before and after NMES-RT. Muscle biopsies and fasting biomarkers were also measured. Following the completion of the respective NMES-RT trials, participants were classified into either high-responders ( n = 8; muscle CSA > 20%) or low-responders ( n = 12; muscle CSA < 20%) based on whole thigh muscle CSA hypertrophy. Whole thigh muscle and knee extensors CSAs were significantly greater ( P < 0.0001) in high-responders (29 ± 7% and 47 ± 15%, respectively) compared to low-responders (12 ± 3% and 19 ± 6%, respectively). There were no differences in total caloric intake or macronutrient intake between groups. Extensor spasticity was lower in the high-responders compared to the low-responders as was the dosage of baclofen. Prior to the intervention, the high-responders had greater body mass compared to the low-responders with SCI (87.8 ± 13.7 vs. 70.4 ± 15.8 kg; P = 0.012), body mass index (BMI: 27.6 ± 2.7 vs. 22.9 ± 6.0 kg/m 2 ; P = 0.04), as well as greater percentage in whole body and regional fat mass ( P < 0.05). Furthermore, high-responders had a 69% greater increase ( P = 0.086) in total Akt protein expression than low-responders. High-responders also exhibited reduced circulating IGF-1 with a concomitant increase in IGFBP-3. Exploratory analyses revealed upregulation of mRNAs for muscle hypertrophy markers [IRS-1, Akt, mTOR] and downregulation of protein degradation markers [myostatin, MurF-1, and PDK4] in the high-responders compared to low-responders. The findings indicate that body composition, spasticity, baclofen usage, and multiple signaling pathways (anabolic and catabolic) are involved in the differential muscle hypertrophy response to NMES-RT in persons with chronic SCI. | Predictors of muscle hypertrophy responsiveness to electrically evoked resistance training after spinal cord injury | 10.1007/s00421-022-05069-0 |
2023-03-01 | Peripheral nerve injury (PNI) is associated with considerable functional impairment. Photobiomodulation (PBM) has demonstrated positive effects regarding neuromuscular repair after PNI when applied locally to the nerve or injured muscle. However, the effects of systemic PBM with transcutaneous application over an important artery, which is also denominated vascular PBM (VPBM), remain unclear. The aim of the study was to compare the effects of VPBM with low-level laser (LLL) and light-emitting diode (LED) on gait, sensitivity and muscle morphology following a PNI. PNI was induced on Wistar rats using the sciatic nerve crushing technique. VPBM was performed over the rat’s artery tail region with LED (850 nm, 40 mW, 3.2 J) and LLL (780 nm, 40 mW, 3.2 J). Gait functionality, mechanical (nociceptive) sensitivity, and morphology of the tibialis anterior muscle were evaluated at 7, 14, and 21 days after injury. An improvement in functional gait was shown in the VPBM-LLL group in all periods. Motor sensitivity was found after 14 days in the VPBM-LLL group. The left/right (L/R) muscle mass ratio revealed a reduction in muscle atrophy in the VPBM-LLL group at 7 days. Muscle fiber diameter increased in the VPBM-LED group at 14 days and increases in the cross-section area were found in the VPBM-LED and VPBM-LLL groups at 7 days. VPBM with both light sources (LED and LLL) positively modulated functioning and neuromuscular recovery following sciatic nerve injury in rats, with more pronounced results when using LLL. Graphical Abstract | Effects of systemic vascular photobiomodulation using LED or laser on sensory–motor recovery following a peripheral nerve injury in Wistar rats | 10.1007/s43630-022-00335-8 |
2023-03-01 | Purpose Aging is a risk factor for several debilitating conditions including those related to chronic back pain and intervertebral disc degeneration, both of which have no cure. Mouse models are useful tools for studying disc degeneration and chronic back pain in a tightly controlled and clinically relevant aging environment. Moreover, mice offer the advantage of carrying out longitudinal studies to understand the etiology and progression of disc pathology induced by genetic or surgical strategies. Previously, age-related behavioral trends of discomfort and enhanced nociception in mice were reported; however, whether these measures are mediated by structural and pathological changes in the disc is unknown. Methods The goal of the present observational study was to identify behavioral correlates of age-related degenerative changes in the disc. Towards this, we collected radiographs from 150 mice (77 females) between three and 23 months of age and measured the disc height index for each level of lumbar disc. Behavioral measures were collected on several of these mice which included rearing and distance travelled in an open field test; time spent in rearing, reaching, immobile, and self-suspended in the tail suspension test; bilateral hind paw licking in response to cold allodynia using acetone; and unilateral hind paw licking in response to heat hyperalgesia using capsaicin. Results Results show that the lower lumbar discs lose height with age and these changes are independent of body composition measures including body weight, bone mineral density, fat mass, lean weight mass, percent fat mass, and percent lean mass. Disc height positively correlates with rearing and mobility in the open field test, immobility in the tail suspension test, and thermal hyperalgesia. Disc height negatively correlates with cold allodynia and rearing in the tail suspension test. Furthermore, mediation analysis shows that the lumbosacral disc significantly mediates the effect of age on rearing in the open field test, but not cold allodynia, suggesting this behavior is a useful measure of age-related axial discomfort due to disc degeneration. Conclusion In summary, the findings from the current study show that disc height are associated with measures of axial discomfort and nociception in mice. | Loss of lumbar disc height with age and its impact on pain and sensitivity associated behaviors in mice | 10.1007/s00586-023-07545-3 |
2023-03-01 | Five years after we published the synthesis of the first diamidocarbene (DAC)-supported amino borylene 4 , we now report the elusive single crystal X-ray structure. The X-ray structure of 4 was found to corroborate our previous computational studies which indicated that the borylene adopted a heterocumulenic geometry with a near linear C (carbene) = B = N unit (175.88(18) ◦ ) as well as short C = B and B = N distances of 1.416(3) and 1.344(3) Å, respectively. Additionally, we further provide a qualitative and quantitative discourse on said structure with respect to the precursor compounds used to prepare 4 as well as to the known cyclic (alkyl) amino carbene (CAAC) analog 2. | A Diamidocarbene-Supported Aminoborylene: Characterization and Discussion of the Elusive Crystal Structure | 10.1007/s10870-022-00950-4 |
2023-03-01 | This study explores the synergistic removal effect of various schemes based on demisters on boiler flue gas dust on a pilot-scale experimental bench. The results show that the dust removal efficiency is 28.43–51.30% when demisters are put into operation alone; the larger the inlet dust concentration of demisters is, the higher the dust removal efficiency will be; but it still cannot reach the 10 mg/Nm 3 ultra-low emission standard. The dust removal efficiency is 93.13% when wet electro-static precipitator and demisters are put into operation simultaneously. Furthermore, the outlet dust concentration is lower than 5 mg/Nm 3 , and the dust removal efficiency of the demisters themselves increases to 67.28%, which has shown a significant improvement compared with operation alone. The dust removal efficiency is 70.98–78.37% when the water-washing layer and demisters are put into operation simultaneously. Moreover, the outlet dust concentration reaches the standard of 10 mg/Nm 3 when the liquid–gas ratio (L/G) is more than 3.5. This research shows that when the inlet dust concentration is ≤ 35 mg/Nm 3 , the method of “water-washing layer + demisters” can be used as an equivalent alternative to the wet electro-static precipitator when L/G ≥ 3.5, which has reference value for reducing the construction cost of ultra-low emission reformation. | Pilot study on demister-based dust removal methods for boiler flue gas | 10.1007/s11356-022-24840-6 |
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