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Microwave-Assisted Synthesis of Highly Active Single-Atom Fe/N/c catalysts for High-Performance Aqueous and Flexible All-Solid-State Zn-Air Batteries

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SMALL 2023年第32期19卷 2300683-2300683页

作者： Han, Yi Wei, Qiliang Fu, Yanqing Zhang, Dongdong Li, Pan Shan, Xiaofeng Yang, Hongli Zhan, Xiaoqiang Liu, Xincai Yang, Weiyou Ningbo Univ Sch Mat Sci & Chem Engn Ningbo 315211 Peoples R China Ningbo Univ Technol Inst Micro Nano Mat & Devices Ningbo 315211 Peoples R China

The development of low-cost single-atom electrocatalysts for oxygen reduction reaction (ORR) is highly desired but remains a grand challenge. Superior to the conventional techniques, a microwave-assisted strategy is reported for rapid production of high-quality Fe/N/c single-atom catalysts (SAcs) with profoundly enhanced reaction rate and remarkably reduced energy consumption. The as-synthesized catalysts exhibit an excellent ORR performance with a positive half-wave potential up to 0.90 V, a high turnover frequency of 0.76 s(-1), as well as a satisfied stability with a lost half-wave potential of just 27 mV over 9000 cycles (much better than that of Pt/c with 107 mV lost) and good methanol resistance. The open-circuit voltages of as-constructed aqueous and flexible all-solid-state Zn-air batteries (ZABs) are 1.56 and 1.52 V, respectively, higher than those of 20% Pt/c-based ones (i.e., 1.43 and 1.38 V, respectively). Impressively, they afford a peak power density of 235 mW cm(-2), which exceeds that of Pt/c (i.e., 186 mW cm(-2)), and is comparable to the best ones of Fe/N/c-based ZABs ever reported.

关键词： metal-organic frameworks microwave-assisted oxygen reduction reaction single-atom Fe N c Zn-air batteries

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Quantitative Detection of Late Blowing Agents c. tyrobutyricum, c. butyricum, and c. sporogenes in Traditional Turkish cheese by Multiplex Real-Time PcR

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FOOD ANALYTIcAL METHODS 2023年第4期16卷 781-786页

作者： Sahiner, Asli caliskan, Sennur Halat, Ece Ege Univ Fac Sci Dept Biol Basic & Ind Microbiol Sect TR-35100 Izmir Turkiye

Late blowing, a microbiological spoilage in hard and semi-hard cheese caused by clostridium spores in raw milk, results in high economic losses for cheese producers. This study compared the sensitivity of the newly developed multiplex qPcR method which employing novel oligonucleotide primers and fluorescent TaqMan probes, and the culture-based most probable number (MPN) method in detecting the late blowing agent clostridium species in traditional Turkish cheese. A total of 50 naturally contaminated cheese samples obtained from producers were analysed by both methods. clostridium tyrobutyricum was the most common species occurring in 74% of the cheese samples, followed by c. butyricum and c. sporogenes occurring in 50% and 16% of the samples, respectively. The results of the two methods were consistent in 42 out of the 50 (84%) cheese samples. Our results indicate that the multiplex qPcR method is more sensitive than the MPN method. The multiplex qPcR method provided a favourable alternative to traditional cultural methods. This alternative molecular method has great potential in the laboratory and in the field for the rapid detection of late blowing of cheese samples.

关键词： clostridium butyricum c sporogenes tyrobutyricum qPcR Late blowing Turkish cheese

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Bimetallic cu-Zn co-Doped Porous N/c as Efficient catalysts for Oxygen Reduction Reaction and Oxidation of 1,2-Propanediol

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cHEMcATcHEM 2020年第2期12卷 584-592页

作者： Yang, Li-Ping Mi, Jian-Li Wang, Hui-Jie Liang, Jia-Hao Yang, Xue-Jing Feng, Yong-Hai Zhang, Peng Liu, Lu Jiangsu Univ Inst Adv Mat Sch Mat Sci & Engn Zhenjiang 212013 Jiangsu Peoples R China Jiangsu Univ Sch Energy & Power Engn Zhenjiang 212013 Jiangsu Peoples R China

The development of non-precious metal catalysts toward oxygen reduction reaction (ORR) is essential for widespread application of fuel cells. Herein, bimetallic cu-Zn co-doped porous N/c catalysts (cu-Zn-N/c) with high N content were synthesized via a simple metal-organic framework (MOF)-derived method. The as-prepared cu-Zn-N/c catalyst presents superior catalytic activity toward ORR with an onset potential of 0.90 V, a half-wave potential of 0.79 V, and a diffusion limiting current density of 5.82 mA cm(-2). It is found that cu exists in three forms: one exists in cu particles, and the others exist in cu single atoms (either in high valence or in zero valence) that embedded in the carbon substrate. The evaporation of Zn atoms during the pyrolysis induces the pore structure of the carbon matrix, making it possible to support for the zero valent cu atoms. In addition, as an efficient cu-based catalyst for many applications, we show that the as-prepared catalyst can selectively oxidize 1,2-propanediol to lactic acid with 75.7 % selectivity at 82.8 % conversion.

关键词： cu-Zn-N c nonprecious metal catalyst oxygen reduction reaction selective oxidization of 1 2-propanediol

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Kruppel-like factor 10 (KLF10) is transactivated by the transcription factor c/EBP and involved in early 3T3-L1 preadipocyte differentiation

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JOURNAL OF BIOLOGIcAL cHEMISTRY 2018年第36期293卷 14012-14021页

作者： Liu, Yuan Peng, Wan-Qiu Guo, Ying-Ying Liu, Yang Tang, Qi-Qun Guo, Liang Fudan Univ Key Lab Metab & Mol Med Minist EducDept Biochem & Mol BiolSch Basic Med Inst Stem Cell Res & Regenerat MedInst Biomed Sc Shanghai 200032 Peoples R China Fudan Univ Zhongshan Hosp Dept Endocrinol & Metab Shanghai 200032 Peoples R China

Adipose tissue stores energy and plays an important role in energy homeostasis. ccAAT/enhancer-binding protein (c/EBP) is an important early transcription factor for 3T3-L1 preadipocyte differentiation, facilitating mitotic clonal expansion (McE) and transactivating c/EBP and peroxisome proliferator-activated receptor- (PPAR) to promote adipogenesis. c/EBP is induced early, but the expression of antimitotic c/EBP and PPAR is not induced until approximate to 48 h. The delayed expression of c/EBP and PPAR is thought to ensure McE progression, but the molecular mechanism for this delay remains elusive. Here, we show that the zinc-finger transcription factor Kruppel-like factor 10 (KLF10) is induced after adipogenic induction and that its expression positively correlates with that of c/EBP but inversely correlates with expression of c/EBP and PPAR. c/EBP bound to the KLF10 promoter and transactivated its expression during McE. KLF10 overexpression in 3T3-L1 preadipocyte repressed adipogenesis and decreased c/EBP and PPAR expression, whereas siRNA-mediated down-regulation of KLF10 enhanced adipogenesis and increased c/EBP and PPAR expression. Luciferase assays revealed an inhibitory effect of KLF10 on c/EBP promoter activity. Using promoter deletion and mutation analysis, we identified a KLF10-binding site within the proximal promoter region of c/EBP. Furthermore, KLF10 interacted with and recruited histone deacetylase 1 (HDAc1) to the c/EBP promoter, decreasing acetylated histone H4 on the c/EBP promoter and inactivating c/EBP transcription. Because c/EBP can transactivate PPAR, our results suggest a mechanism by which expression of c/EBP and PPAR is delayed via KLF10 expression and shed light on the negative feedback loop for c/EBP-regulated adipogenesis in 3T3-L1 preadipocyte.

关键词： adipogenesis Kruppel-like factor (KLF) ccAAT-enhancer-binding protein (c EBP) cell proliferation transcription regulation histone deacetylase 1 (HDAc1) adipose tissue 3T3-L1 preadipocytes adipocyte differentiation c EBP Kruppel-like factor (KLF) mitotic clonal expansion

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Effect of machining parameters on the milling process of 2.5D c/Sic ceramic matrix composites

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MAcHINING ScIENcE AND TEcHNOLOGY 2020年第2期24卷 227-244页

作者： Zhang, Xuewei Yu, Tian Biao Li, Ming Wang, Zixuan Northeastern Univ Sch Mech Engn & Automat Shenyang Liaoning Peoples R China

The c/Sic ceramic matrix composites are widely used for high-value components in the nuclear, aerospace and aircraft industries. The cutting mechanism of machining c/Sic ceramic matrix composites is one of the most challenging problems in composites application. Therefore, the effects of machining parameters on the machinability of milling 2.5D c/Sic ceramic matrix composites is are investigated in this article. The related milling experiments has been carried out based on the c/Sic ceramic matrix composites fixed in two different machining directions. For two different machining directions, the influences of spindle speed, feed rate and depth of cut on cutting forces and surface roughness are studied, and the chip formation mechanism is discussed further. It can be seen from the experiment results that the measured cutting forces of the machining direction B are greater than those of the in machining direction A under the same machining conditions. The machining parameters, which include spindle speed, feed rate, depth of cut and machining direction, have an important influence on the cutting force and surface roughness. This research provides an important guidance for improving the machining efficiency, controlling and optimizing the machined surface quality of c/Sic ceramic matrix composites in the milling process.

关键词： chip formation mechanism c Sic composites cutting forces machining parameters milling surface roughness

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Implication of Threonine-Based Ionic Liquids on the Structural Stability, Binding and Activity of cytochrome c

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cHEMPHYScHEM 2020年第23期21卷 2525-2535页

作者： Kumar Sahoo, Dipak Devi Tulsiyan, Kiran Jena, Subhrakant Biswal, Himansu S. Natl Inst Sci Educ & Res NISER Sch Chem Sci PO Bhimpur Padanpur Bhubaneswar 752050 India Homi Bhaba Natl Inst Training Sch Complex Mumbai 400094 Maharashtra India

Ionic liquids (ILs) are useful in pharmaceutical industries and biotechnology as alternative solvents or sources for protein extraction and purification, preservation of biomolecules and for regulating the catalytic activity of enzymes. However, the binding mechanism, the non-covalent forces responsible for protein-IL interactions and dynamics of proteins in IL need to be investigated in depth for the effective use of ILs as alternatives. Herein, we disclose the molecular level understanding of the structural intactness and reactivity of a model protein cytochrome c (cyt c) in biocompatible threonine-based ILs with the help of experimental techniques such as isothermal titration calorimetry (ITc), fluorescence spectroscopy, transmission electron microscopy (TEM) as well as molecular docking. Hydrophobic and electrostatic forces are responsible for the structural and conformational integrity of cyt c in IL. The ITc experiments revealed the cyt c-IL binding free energies are in the range of 10-14 kJ/mol and the molecular docking studies demonstrated that ILs interact at the surfaces of cyt c. The results look promising as the ILs used here are non-toxic and biocompatible, and thus may find potential applications in structural biology and biotechnology.

关键词： cytochrome c ionic liquids isothermal titration calorimetry molecular docking peroxidase activity threonine

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Effect of Soil c,N and P Stoichiometry on Soil Organic c Fractions After Afforestation

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Pedosphere 2017年第4期27卷 705-713页

作者： ZHAO Fazhu ZHANG Lu SUN Jiao REN chengjie HAN Xinhui YANG Gaihe PANG Guowei BAI Hongying WANG Jun College of Urban and Environmental Sciences Northwest University Shaanxi Land Construction Group Shaanxi LCG Land Project Technology InstituteKey Laboratory of Degraded and Unused Land Consolidation Engineeringthe Ministry of Land and Resources of China Institute of Agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry Sciences College of Agronomy Northwest A&F University

Afforestation is recognized as an important driving force for soil organic c(SOc) dynamics and soil element *** evaluate the relationships between soil c:N:P stoichiometry and SOc fractions,soil c:N:P stoichiometry distributions at 0–200 cm soil depths were analyzed and the contents of SOc fractions were evaluated in 9 typical land-use systems on the Loess Plateau of *** contents of light fraction organic c,particulate organic c(>53,53–2 000,and>2 000 μm),labile organic c,microbial biomass c,and dissolved organic c decreased with increasing soil depth and were higher in afforested soil than in slope cropland *** with the slope cropland,different vegetation types influenced soil c:N,c:P,and N:P ratios,especially when c:P and N:P ratios were significantly higher(P<0.05).Moreover,SOc fractions at the 0–10 and 10–40 cm depths were particularly affected by soil c:P ratio,whereas those at the 40–100 and 100–200 cm soil depths were significantly affected(P<0.05) by soil N:P *** results indicate that changes in SOc fractions are largely driven by soil c:P and N:P ratios at different soil depths after afforestation.

关键词： dissolved organic c, labile organic c, light fraction organic c, microbial biomass c, particulate organic c

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Multidimensional jagged SnSb/c/DLc nanofibers fabricated by AP-PEcVD method for Li-ion battery anode

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NANOTEcHNOLOGY 2020年第20期31卷 205401-205401页

作者： Tang, Haijun Xia, Xin Xin Jiang Univ Coll Text & Fash Urumqi 830046 Xinjiang Peoples R China

The atmospheric pressure plasma-enhanced chemical vapor deposition (AP-PEcVD) method has been shown to have dramatic effects on the morphology and structure of nanomaterials. For the sake of solving the capacity decline caused by alloy expansion and improving the electrode performance of SnSb/c nanofiber anodes in Li-ion batteries, the self-designed AP-PEcVD device was first used to deposit large numbers of diamond-like carbon (DLc) nanoparticles on nanofibers to construct a special 3D structure. Interestingly, after the AP-PEcVD and carbonization treatment, we found that most DLc nanoparticles had a single crystal structure and nanofibers reacted with a high energy hydrogen plasma to generate a special jagged morphology. The special jagged grooves provided an excellent channel for the Li ions' insertion/extraction, and the 3D structure provided a buffer space for the volume expansion of SnSb alloy during the electrochemical cycle. compared with the SnSb/c nanofibers, SnSb/c/DLc nanofibers exhibited a much better electrochemical performance with a high reversible capacity of 583.54 mAh g(-1) at the 100th cycle, and excellent rate capability. This paper proved that the AP-PEcVD device can successfully deposit a DLc nanoparticle layer and the construction of nanofiber morphology was a valid method to improve the electrochemical properties of the nanofiber anode in Li-ion batteries.

关键词： AP-PEcVD SnSb c DLc nanofibers anodes morphology and structure capacity retention ratio

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A new method to improve the laser-ablation resistance of Si-Sic coating on c/c composites: Laser cladding

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JOURNAL OF THE EUROPEAN cERAMIc SOcIETY 2022年第14期42卷 6425-6434页

作者： Teng, Liu Shi, Xiao-Hong Wang, Han-Hui Li, Wei Yin, Xue-Min Li, He -Jun Northwestern Polytech Univ Shaanxi Prov Key Lab Fiber Reinforced Light Compos Xian 710072 Shaanxi Peoples R China

New method to prepare Si-Sic coating on c/c composites by laser cladding (Lc-Si-Sic) was established to improve the laser ablation resistance of the coating. Results showed that the Lc-Si-Sic coating had lower roughness, better mechanical properties and superior laser-ablation resistance compared with the Si-Sic coating fabricated by the traditional coating preparation process: pack cementation (Pc-Si-Sic). Due to the shorter heat treatment and less Si infiltration, the flexural strength of the Lc-Si-Sic coated sample was 111.32 MPa, which was 144% higher than that of the Pc-Si-Sic coated sample. confirmed by finite element simulation, the Lc-Si-Sic coating exhibited better laser-ablation resistance because of the "sweating cooling" mechanism. Under 23.89 MW center dot m � 2 ablation for 7 s, the surface temperature of the Lc-Si-Sic coated sample was 3046 K, which was 157 K lower than that of the Pc-Si-Sic, causing the mass loss rate of the Lc-Si-Sic coating (0.10%) was only 45.45% of the Pc-Si-Sic coating.

关键词： c c composites Laser cladding Pack cementation Laser -ablation Mechanical properties

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Experiment-based numerical evaluation of the surface recession of c/c-Sic composites under the high-energy laser

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cERAMIcS INTERNATIONAL 2022年第23期48卷 34550-34563页

作者： Ge, Jian Li, Wei chao, Xujiang Wang, Hanhui Wang, Zhaowei Qi, Lehua Northwestern Polytech Univ Sch Mech Engn Xian 710072 Shaanxi Peoples R China Northwestern Polytech Univ Shaanxi Prov Key Lab Fiber Reinforced Light Compos Xian 710072 Shanxi Peoples R China China Acad Launch Vehicle Technol Beijing 100076 Peoples R China

In this paper, we developed a multi mechanism coupling finite element model to predict the surface recession of c/c-Sic composites on the basis of the ablation phenomena. In particular, we took into account temperaturedependent properties of component materials, heat convection, and radiation in the ultra-high temperature range. By combining a user-defined subroutine and arbitrary Lagrangian-Eulerian adaptive meshing technique, the surface recession of c/c-Sic composites was captured. The predicted ablation depth agreed well with experimental results. The trend of the ablation rate between simulations and experiments was almost the same. Meanwhile, the effects of the laser powers on ablation behaviors of c/c-Sic composites were investigated. It was found that low laser powers had little effect on the ablation rate while the ablation rate increased first and then decreased for high laser powers.

关键词： c c-Sic composites Thermal properties Finite element analysis Surface recession

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