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The hot deformation behavior and microstructure evolution of a recently developed 2Cr12Ni4Mo3VNbN martensitic stainless steel are examined through hot compression tests conducted within the temperature range of 900–1200 °C and the strain rate range of 0.01–10 s−1. The constitutive equation and processing maps corresponding to hot deformation are established. The activation energy for hot deformation of 2Cr12Ni4Mo3VNbN steel is determined to be ≈457491.77 J mol−1. Simultaneously, the microstructure evolution during hot deformation is studied. Based on the processing maps and microstructure evolution analysis, it is concluded that the optimal windows for hot processing are within the temperature range of 1106–1150 °C and the strain rate range of 0.01–2.7 s−1, as well as at 1200 °C within the strain rate range of 1–2.7 s−1, exhibiting a power dissipation efficiency of 0.32. As the temperature increases and the strain rate decreases, the degree of dynamic recrystallization escalates. [ABSTRACT FROM AUTHOR]

A flavor-related enzyme fromToona sinensis(TS), ɣ-glutamyl-transpeptidase (GGT), was purified 40.67-fold with 13.40% recovery using ammonium sulfate precipitation, dialysis and gel filtration chromatography. Gel filtration chromatography and sodium dodecyl sulfate acryl amide gel electrophoresis (SDS-PAGE) revealed that GGT was a heterodimer with a molecular weight of 90 kDa, and the molecular size of its two subunits was 26 kDa and 64 kDa, respectively. The apparent Km and Vmax of GGT were 3.623 μmol/mL and 2.831 μmol/mL/min of protein, respectively. The optimum reaction temperature was 60°C, while the optimum pH was 7.0. GGT can tolerate temperatures of 70°C for a short time and can keep stable activity at 60°C for more than 2 hours. The effect of metal ions on GGT activity showed that Cu2+and Zn2+had strong inhibition, while Fe3+had strong activation, and other metal ions had only a slight effect. LC-MS analysis indicated that GGT catalyzed (S, S)-γ-glutamyl-(cis-S-1-propenyl)-thioglycine, a flavor precursor found in TS, to release glutamic acid moiety. [ABSTRACT FROM PUBLISHER]

High-entropy alloys (HEAs) comprising five or more elements in near-equiatomic proportions have attracted ever increasing attention for their distinctive properties, such as exceptional strength, corrosion resistance, high hardness, and excellent ductility. The presence of multiple adjacent elements in HEAs provides unique opportunities for novel and adaptable active sites. By carefully selecting the element configuration and composition, these active sites can be optimized for specific purposes. Recently, HEAs have been shown to exhibit remarkable performance in electrocatalytic reactions. Further activity improvement of HEAs is necessary to determine their active sites, investigate the interactions between constituent elements, and understand the reaction mechanisms. Accordingly, a comprehensive review is imperative to capture the advancements in this burgeoning field. In this review, we provide a detailed account of the recent advances in synthetic methods, design principles, and characterization technologies for HEA-based electrocatalysts. Moreover, we discuss the diverse applications of HEAs in electrocatalytic energy conversion reactions, including the hydrogen evolution reaction, hydrogen oxidation reaction, oxygen reduction reaction, oxygen evolution reaction, carbon dioxide reduction reaction, nitrogen reduction reaction, and alcohol oxidation reaction. By comprehensively covering these topics, we aim to elucidate the intricacies of active sites, constituent element interactions, and reaction mechanisms associated with HEAs. Finally, we underscore the imminent challenges and emphasize the significance of both experimental and theoretical perspectives, as well as the potential applications of HEAs in catalysis. We anticipate that this review will encourage further exploration and development of HEAs in electrochemistry-related applications. [ABSTRACT FROM AUTHOR]

In order to improve the hydrophilicity of coal and solve the potential environmental problems caused by chemical surfactants, in this study, a biosurfactant-producing bacteria (PLD01) was screened from coal through biochemical test screen. The species, biosurfactant types and composition analysis of the strain were studied. PLD01 was identified by 16S rRNA, and exhibited 99% sequence similarity with Pseudomonas bacteria. Fourier Transform Infrared Spectrophotometer (FTIR) analysis showed the presence of N-H, carboxyl groups, and glycosidic bonds in biosurfactants, which were determined as glycolipids. Liquid Chromatography-Mass Spectrometry (LC-MS) analysis showed that the biosurfactants had Mono-rhamno-mono-lipidic congeners (Rha-C 12), Di-rhamno-mono-lipidic congeners (Rha-Rha-C 10), and Mono-rhamno-di-lipidic congeners (Rha-C 12 -C 10 /Rha-C 10 -C 12). Finally, the analysis of the potential and performance of PLD01 to produce surfactants revealed that it was an effective biosurfactant. The yield of biosurfactant was 4.35 g/L when OD 600 = 1.34 and cultured for 7 d. The critical micelle concentration (CMC) of the separated biosurfactant was as low as 50.0 mg/L, which reduced the surface tension of water from 72.8 mN/m to 40.6 mN/m. The modified wetting effect was better than the common chemical surfactant sodium dodecyl sulfate (SDS). Therefore, the biosurfactant-producing bacteria have good engineering application prospects. [Display omitted] • Biosurfactant-producing bacteria was screened from coal for the first time. • The biosurfactant produced by PLD01 can improve the hydrophilicity of coal dust. • FTIR and LC-MS showed that the biosurfactant was glycolipid. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the feasibility of using a similarity coefficient map (SCM) in improving the morphological evaluation of T2* weighted (T2* W) magnatic resonance imaging (MRI) for renal cancer. Simulation studies and in vivo 12-echo T2* W experiments for renal cancers were performed for this purpose. The results of the first simulation study suggest that an SCM can reveal small structures which are hard to distinguish from the background tissue in T2* W images and the corresponding T2* map. The capability of improving the morphological evaluation is likely due to the improvement in the signal-to-noise ratio (SNR) and the carrier-to-noise ratio (CNR) by using the SCM technique. Compared with T2* W images, an SCM can improve the SNR by a factor ranging from 1.87 to 2.47. Compared with T2* maps, an SCM can improve the SNR by a factor ranging from 3.85 to 33.31. Compared with T2* W images, an SCM can improve the CNR by a factor ranging from 2.09 to 2.43. Compared with T2* maps, an SCM can improve the CNR by a factor ranging from 1.94 to 8.14. For a given noise level, the improvements of the SNR and the CNR depend mainly on the original SNRs and CNRs in T2* W images, respectively. In vivo experiments confirmed the results of the first simulation study. The results of the second simulation study suggest that more echoes are used to generate the SCM, and higher SNRs and CNRs can be achieved in SCMs. In conclusion, an SCM can provide improved morphological evaluation of T2* W MR images for renal cancer by unveiling fine structures which are ambiguous or invisible in the corresponding T2* WMR images and T2* maps. Furthermore, in practical applications, for a fixed total sampling time, one should increase the number of echoes as much as possible to achieve SCMs with better SNRs and CNRs. [ABSTRACT FROM AUTHOR]

Objective To explore the myoblast formation around the urethra and increase in urethral resistance of bone marrow mesenchymal stem cells or muscle-like cells/calcium alginate composite gel injection therapy and effect on LPP in SUI rat model. Methods Isolation, cultivation, and identification of SD rat bone marrow mesenchymal stem cell were performed. 5-Azacytidine was introduced to induce muscle-like cells. SUI was produced in 72 6-week-old female Sprague-Dawley rats, which were divided into four groups: stem cell-gel group, muscle-like cell-gel group, Gel group, and mock control group. One, 4, and 8 weeks after injection, the leak point pressure (LPP) was measured. HE staining of Desmin and α-skeletal muscle actin (α-SMA) were performed. Results At 4 and 8 weeks after injection in stem cell-gel group and muscle-like cell-gel group, growth of blood vessels gradually increased at gel edge, BMSC, and muscle-like cells gathered around the new blood vessels observed by fluorescence tracer, muscle-like cells grew into elongated spindle-like cells, Desmin, and α-SMA staining were obviously positive expression. LPP determinations of the mock control group compared with the Gel groups were significantly different. Conclusions Compound of BMSC, muscle-like cells, and calcium alginate composite gel has the potential to differentiate into muscle cells in the microenvironment of SUI rat model. It is found by LPP measurement that the correlation between the increase in urethral resistance and the volume effect of calcium alginate gel is high. Neurourol. Urodynam. 32: 281-286, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

• Sisal-like porous MoO 2 nanosheet arrays grown on Ni foam are synthesized by a facile process. • The MoO 2 /NF exhibits exceptional activity and durability for both NRR and OER. • A remarkable ammonia production performance is achieved in two-electrode full N 2 electrolysis. • The valence state of Mo species plays a key role in promoting NRR activity. Developing efficient electrocatalysts for direct N 2 electrolysis that includes two key reactions of oxygen evolution reaction (OER) at the anode and nitrogen reduction reaction (NRR) at the cathode is an appealing yet challenging task. Herein, Ni foam (NF) supported sisal-like porous MoO 2 nanosheet array (MoO 2 /NF) was synthesized through a facile hydrothermal and subsequent annealing process. It is shown that in the NRR process the Mo4+ in MoO 2 /NF is more favorable in an associative mechanism of NRR than Mo6+ in MoO 3 /NF, thus yielding an impressive ammonia electrosynthesis activity (NH 3 yield rate: 9.56 μg h−1 cm−2; Faradaic efficiency: 5.14%) in 0.1 M KOH. Moreover, the sisal-like porous nanosheet array structure not only provides a high surface area for abundant accessible active sites, but also limits the coalescence of gas bubbles, enabling active sites better exposed to nitrogen by removing the small gas bubbles rapidly. The MoO 2 /NF also shows excellent performance for the OER in 0.1 M KOH, exhibiting a small overpotential of 340 mV to realize a current density of 10 mA cm−2. In two-electrode full N 2 electrolysis, a remarkable ammonia production performance with an ammonia yield of 5.73 μg h−1 cm−2, an FE of 15.8%, and good long-term stability for at least 24 h is obtained. [ABSTRACT FROM AUTHOR]

In contrast to the thermodynamically unfavorable anodic oxygen evolution reaction, the electrocatalytic urea oxidation reaction (UOR) presents a more favorable thermodynamic potential. However, the practical application of UOR has been hindered by sluggish kinetics. In this study, hierarchical porous nanosheet arrays featuring abundant Ni‐WO3 heterointerfaces on nickel foam (Ni‐WO3/NF) is introduced as a monolith electrode, demonstrating exceptional activity and stability toward UOR. The Ni‐WO3/NF catalyst exhibits unprecedentedly rapid UOR kinetics (200 mA cm−2 at 1.384 V vs. RHE) and a high turnover frequency (0.456 s−1), surpassing most previously reported Ni‐based catalysts, with negligible activity decay observed during a durability test lasting 150 h. Ex situ X‐ray photoelectron spectroscopy and density functional theory calculations elucidate that the WO3 interface significantly modulates the local charge distribution of Ni species, facilitating the generation of Ni3+ with optimal affinity for interacting with urea molecules and CO2 intermediates at heterointerfaces during UOR. This mechanism accelerates the interfacial electrocatalytic kinetics. Additionally, in situ Fourier transform infrared spectroscopy provides deep insights into the substantial contribution of interfacial Ni‐WO3 sites to UOR electrocatalysis, unraveling the underlying molecular‐level mechanisms. Finally, the study explores the application of a direct urea fuel cell to inspire future practical implementations. [ABSTRACT FROM AUTHOR]

The elevated atmospheric CO 2 concentration is well known to have an important effect on soil nutrient cycling. Ammonia oxidation, mediated by ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB), is the rate-limiting step in soil nitrification, which controls the availability of two key soil nutrients (ammonium and nitrate) for crops. Until now, how the AOA and AOB communities in paddy soils respond to elevated CO 2 remains largely unknown. Here, we examined the communities of AOA and AOB and nitrification potential at both surface (0–5 cm) and subsurface (5–10 cm) soil layers of paddy fields under three different CO 2 treatments, including CK (ambient CO 2 concentration), LT (CK + 160 ppm of CO 2) and HT (CK + 200 ppm of CO 2). The elevated CO 2 was found to have a greater impact on the community structure of AOB than that of AOA in surface soils as revealed by high-throughput sequencing of their amo A genes. However, no obvious variation of AOA or AOB communities was observed in subsurface soils among different CO 2 treatments. The abundance of AOA and AOB, and nitrification potential were significantly increased in surface soils under elevated CO 2. The variation of AOB abundance correlated well with the variation of nitrification potential. The soil water content and dissolved organic carbon content had important impacts on the dynamic of AOB communities and nitrification potential. Overall, our results showed different responses of AOA and AOB communities to elevated CO 2 in paddy ecosystems, and AOB were more sensitive to the rising CO 2 concentration. [Display omitted] • Elevated CO 2 had a significant impact on ammonia oxidizers primarily in surface soils. • Elevated CO 2 had a greater impact on community composition of AOB than that of AOA. • Elevated CO 2 stimulated the nitrification potential and growth of both AOA and AOB. • Variation of AOB abundance positively correlated with that of nitrification potential. • Soil dissolved organic carbon had a positive impact on nitrification potential. The rising CO 2 concentration positively affected soil AOA and AOB in paddy fields, leading to an increase in nitrification rates. [ABSTRACT FROM AUTHOR]

To reveal the bonding effect of alloying elements in high entropy alloys and the source of structural stability of alloys, an as-cast Al 0 · 5 CrCuFeMnTi high entropy alloy was synthesized by arc melting under argon protection. The results show that the as-cast alloy is composed of a hexagonal close-packed (HCP) and a body-centered cubic (BCC) structure, and there is a distinct phase interface with a disordered arrangement of atoms between the dendritic (DR) and interdendritic (ID) regions. The calibrated (002), (110), and (112) crystal faces determined through high-resolution transmission electron microscopy confirm that DR phase has the HCP structure, while the ID phase forms solid solutions with the BCC structure by calibrated (110), (01-1), and (12-1) crystal faces. The results from first principles calculations show that the structural stability of the alloy is improved by the strong covalent bonding between Fe and Al, Cr, Fe, Ti atoms in the DR region, and between Al and Cu, Mn atoms in the ID region. The calculated results of solid solution parameters show that the atomic size difference and the mixing enthalpy of this alloy satisfy the criteria for stable solid solutions. • Strong covalent bond bonding between Fe and Al, Cr, Fe, Ti atoms is the main source of structural stability of DR phase. • Structural stability of the ID phase is mainly due to the strong covalent bond between Al and Cu, Mn atoms. • The reduced mixing enthalpy balances the increased lattice distortion, resulting in instability of the crystal structure. [ABSTRACT FROM AUTHOR]

The slow reaction kinetics of oxygen electrode is the bottleneck restricting the development of rechargeable Zn-air batteries (ZABs). In order to further improve the energy conversion efficiency of ZABs, a novel urea-assisted ZAB system was proposed by replacing oxygen evolution reaction (OER) with urea oxidation reaction (UOR) with lower theoretical thermodynamic potential. Inspired by nature's ingenious structure-function, a "leaf-branch" CoNi@NCNTs-LDH/CC binary-site electrocatalyst was designed for the above system, where spatially separated branches and leaves serve as the main active sites for ORR and UOR, respectively. A build-in electric field from CoNi-LDH to CoNi@NCNTs is formed at the interface of the composite, which plays a command effect, effectively triggering the accumulation of O 2 and urea reactants around the CoNi and LDH sites, respectively, and thus improving the efficiency of both ORR and UOR reactions. Based on that, a conceptual urea-assisted rechargeable ZAB is demonstrated to have significantly decreased charging voltage, higher energy conversion efficiency (74.6 %) compared with the conventional ZAB, as well as high urea elimination rates. Considering the urea-assisted ZAB with high energy conversion efficiency and wastewater treatment versatility as an energy transfer station applied in a high value-added agricultural system, uninterrupted hydrogen production and wastewater treatment of agricultural wastewater can be simultaneously achieved using sustainable energy sources. [Display omitted] • A novel urea-assisted rechargeable ZAB system is innovatively proposed. • Through biomimetic design, a "leaf-branch" binary-site electrocatalyst is prepared. • CoNi@NCNTs-LDH/CC exhibits excellent ORR and UOR bifunctional activity. • The built-in electric field regulates the adsorption of reactants at different sites. • Hydrogen production and wastewater treatment of agricultural wastewater can be realized simultaneously. [ABSTRACT FROM AUTHOR]