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Design and fabrication of c-Mn_0.5cd_0.5S/cu3P ternary heterojunction catalyst for photocatalytic hydrogen evolution

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2021年第59期46卷 30382-30392页

作者： Fang, Ningjie Song, Xincheng Zhang, Mingyue chu, Yinghao Sichuan Univ Coll Architecture & Environm Chengdu 610065 Sichuan Peoples R China Natl Engn Technol Res Ctr Flue Gas Desulfurizat Chengdu 610065 Sichuan Peoples R China

Photocatalytic hydrogen evolution from water splitting is a promising strategy to solve the energy demand of human beings. Here, we first designed a c-Mn0.5cd0.5S/cu3P ternary heterojunction catalyst for photocatalytic hydrogen production. The results show that the combination of c and cu3P can effectively improve the photocatalytic activity of Mn0.5cd0.5S. c-Mn0.5cd0.5S loading with 5 wt% cu3P exhibits the highest hydrogen evolution rate (44.1 mmol g(-1) h(-1)), which is 3.2 and 2.8 times higher than that of pure Mn0.5cd0.5S (13.7 mmol g(-1) h(-1)) and Mn0.5cd0.5S/3 wt%Pt (15.6 mmol g(-1) h(-1)), respectively. In addition, it shows a high hydrogen evolution rate (19.6 mmol g(-1) h(-1)) under visible light (>= 420 nm) irritation and the apparent quantum efficiency (AQE) is detected to be 3.2% at 420 nm. The enhanced photocatalytic activity can be attributed to the good conductivity of c and the formation of p-n heterojunction, which is beneficial for light harvesting and the separation and transportation of charge carriers. Besides, a possible mechanism is proposed. This work provides an effective way to improve the photocatalytic activity of Mn0.5cd0.5S by using non noble metal co-catalysts. (c) 2021 Hydrogen Energy Publications LLc. Published by Elsevier Ltd. All rights reserved.

关键词： Photocatalytic Hydrogen evolution c cu 3 P Mn 0 5 cd 0 5 S

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Synthetic ablations in the c. elegans nervous system

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NETWORK NEUROScIENcE 2020年第1期4卷 200-216页

作者： Towlson, Emma K. Barabasi, Albert-Laszlo Univ Network Sci Inst Dept Phys NE Boston MA USA MIT Media Lab Cambridge MA USA Univ Network Sci Inst Dept Phys NE Boston MA USA Brigham & Women's Hosp Harvard Med Sch Dept Med Boston MA USA Univ Dept Network & Data Sci Cent European Budapest Hungary

Author Summary "Synthetic lethality" in cell biology is an extreme example of the effects of higher order genetic interactions: The simultaneous knockout of two or more individually nonessential genes leads to cell death. We define a neural analog to this concept in relation to the locomotor response to gentle touch in c. elegans. Two or more neurons are synthetic essential if individually they are not required for this behavior, yet their combination is. We employ a network control approach to systematically assess all pairs and triplets of neurons by their effect on body wall muscle controllability, and find that only surprisingly small sets of neurons are synthetic essential. They are highly localized in the nervous system and predicted to affect control over specific sets of muscles. Synthetic lethality, the finding that the simultaneous knockout of two or more individually nonessential genes leads to cell or organism death, has offered a systematic framework to explore cellular function, and also offered therapeutic applications. Yet the concept lacks its parallel in neuroscience-a systematic knowledge base on the role of double or higher order ablations in the functioning of a neural system. Here, we use the framework of network control to systematically predict the effects of ablating neuron pairs and triplets on the gentle touch response. We find that surprisingly small sets of 58 pairs and 46 triplets can reduce muscle controllability in this context, and that these sets are localized in the nervous system in distinct groups. Further, they lead to highly specific experimentally testable predictions about mechanisms of loss of control, and which muscle cells are expected to experience this loss.

关键词： c elegans Graph theory Network control theory Neuronal ablations Synthetic lethality

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Effects of spring fire and slope on the aboveground biomass, and organic c and N dynamics in a semi-arid grassland of northern china

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Journal of Arid Land 2019年第2期11卷 267-279页

作者： ZHAO Xiang HU Shuya DONG Jie REN Min ZHANG Xiaolin DONG Kuanhu WANG changhui College of Animal Science and Veterinary Medicine Shanxi Agricultural University State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing Institute of Science and Technology Information

The aboveground primary production is a major source of carbon(c) and nitrogen(N) pool and plays an important role in regulating the response of ecosystem and nutrient cycling to natural and anthropogenic disturbances. To explore the mechanisms underlying the effect of spring fire and topography on the aboveground biomass(AGB) and the soil c and N pool, we conducted a field experiment between April 2014 and August 2016 in a semi-arid grassland of northern china to examine the effects of slope and spring fire, and their potential interactions on the AGB and organic c and total N contents in different plant functional groups(c_3 grasses, c_4 grasses, forbs, Artemisia frigida plants, total grasses and total plants).The dynamics of AGB and the contents of organic c and N in the plants were examined in the burned and unburned plots on different slope positions(upper and lower). There were differences in the total AGB of all plants between the two slope positions. The AGB of grasses was higher on the lower slope than on the upper slope in July. On the lower slope, spring fire marginally or significantly increased the AGB of c_3 grasses, forbs, total grasses and total plants in June and August, but decreased the AGB of c_4 grasses and *** plants from June to August. On the upper slope, however, spring fire significantly increased the AGB of forbs in June, the AGB of c_3 grasses and total grasses in July, and the AGB of forbs and c_4 grasses in August. Spring fire exhibited no significant effect on the total AGB of all plants on the lower and upper slopes in 2014 and 2015. In 2016, the total AGB in the burned plots showed a decreasing trend after fire burning compared with the unburned plots. The different plant functional groups had different responses to slope positions in terms of organic c and N contents in the plants. The lower and upper slopes differed with respect to the organic c and N contents of c_3 grasses, c_4 grasses, total grasses, forbs, A. frigida plan

关键词： aboveground biomass plant functional group spring fire slope position N content organic c content semi-arid grassland

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Efficient Electrocatalytic Performance of WP Nanorods Propagated on WS2/c for Hydrogen Evolution Reduction

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cHEMELEcTROcHEM 2020年第14期7卷 3082-3088页

作者： Yang, Jinzhou Yu, Zong-Bao Sun, Wei Li, Yue Wu, Hongda Geng, Zhongxing Yang, Zhanxu Liaoning Shihua Univ Sch Petrochem Engn Fushun 113001 Liaoning Peoples R China

Through a stepwise synthesis, intercalation followed by chemical vapor deposition (cVD) method, WP nanorods have been grown on the surface of WS2/c composite. compared to WS2/c, WP nanorods@WS2/c demonstrate better hydrogen evolution reaction (HER) activity and long-term chronopotentiometric stability as well as suitability in both acid electrolyte and alkaline electrolyte. In order to uncover the enhanced HER property reason, systematic characterizations were applied to assist analyzing. The characterizations used include X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), electrochemical active surface area (EcSA), Raman, and BET. Based on the analysis, it points that improved EcSA, synergy between WS(2)and WP nanorods, and enhanced degree of graphitization as well, leads to better HER activities of WP nanorods@WS2/c over WS2/c. This work highlights significant role of WP nanorods in WP/WS2/c three-phase composite in electrocatalytic hydrogen evolution and may evoke new interest in related nanostructure study.

关键词： WP nanorods@WS2 c hydrogen evolution reduction chemical vapor deposition

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Ta(B, c, N) and (Ta, Mi)(B, c, N) (Mi = Nb, W) ceramics by high-energy ball milling: processing and solution mechanisms

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JOURNAL OF THE AMERIcAN cERAMIc SOcIETY 2023年第1期106卷 699-708页

作者： Guan, Jingyi Li, Daxin Yang, Zhihua Wang, Bingzhu Jia, Dechang Zhou, Yu Harbin Inst Technol Sch Mat Sci & Engn Inst Adv Ceram Harbin 15000 Peoples R China Harbin Inst Technol Key Lab Adv Struct Funct Integrat Mat & Green Mfg Harbin Peoples R China Harbin Inst Technol Chongqing Inst Chongqing Peoples R China

In order to study the solid-solution process between amorphous BcN and metal Ta, Ta(B, c, N), (Ta, Nb)(B, c, N), and (Ta, W)(B, c, N) ceramics were prepared by high-energy ball milling, and their phase composition, microstructures, and binding bonds have been analyzed. The results show that all the three ceramics are hard agglomeration state, formed by stacking of nanoparticles. The mechanical alloying process is accompanied by the formation of chemical bonds, such as B-Ta, N-Ta, c-Ta, and O-Ta for Ta(B, c, N) ceramic, and the order of solid solution is c > N > B. When heated at 1500 degrees c, a second diboride phase precipitates from (Ta, Nb)(B, c, N) ceramic, whereas the second phase of Wc gradually dissolved from (Ta, W)(B, c, N) ceramic. This work provides theoretical and data supporting to analyze the solid-solution process of Ta(B, c, N) ceramic.

关键词： high-energy ball milling microstructure solid solution Ta(B c N) ceramic

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Investigation of the bulging mechanism of c/Sic coating through in situ optical observation and numerical simulation

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cERAMIcS INTERNATIONAL 2021年第14期47卷 20456-20466页

作者： Kong, Yi Zhang, Jinsong Yue, Mengkun Yue, Wen Qu, Zhe Wang, Xian Wei, Dong Gui, Yewei Tang, Yunlong Feng, Xue China Univ Geosci Sch Engn & Technol Beijing 100083 Peoples R China Tsinghua Univ Dept Engn Mech AML Beijing 100084 Peoples R China Tsinghua Univ Ctr Mech & Mat Beijing 100084 Peoples R China Inst Flexible Elect Technol THU Flexible Integrated Circuit Ctr Jiaxing 314006 Peoples R China China Aerodynam Res & Dev Ctr Sate Key Lab Aerodynam Mianyang 621000 Sichuan Peoples R China China Univ Geosci Beijing Zhengzhou Res Inst Zhengzhou 450001 Peoples R China

carbon fibre-reinforced silicon carbide composites (c/Sic) are a type of high-temperature structural ceramics that can be widely applied in aerospace, hypersonic aircraft, and military fields. However, the practical application of such materials in some complex high-temperature environments is still limited owing to drawbacks such as the bulging problem. In this study, the bulging of a c/Sic coating in a high-temperature wind tunnel is investigated. The surface data of specimens in the high-temperature arc wind tunnel were obtained using optical visualisation equipment, and the entire process of the formation of coating bulges, and their evolution and fusion is illustrated. Then, a fully coupled thermal fluid-solid simulation model is established, and the influence of defects on the internal heat transfer of materials is analysed. Further, the thermal fluid-solid coupling simulation technology is also used to analyse the bulging process of the coating to understand the mechanism of chemical reactions in defects between the coating and substrate. This work can serve as a guide for the screening and improvement of the material coating process.

关键词： c Sic coatings High temperature Bulging coupling simulation Defects

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Exploring How (Ti plus Mo)/c and Ti/Mo Influence the Precipitation Behaviors within Microalloyed Steels: Experimental Evidence and Related Patents Investigation

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JOURNAL OF MATERIALS ENGINEERING AND PERFORMANcE 2020年第3期29卷 1882-1891页

作者： chen, chih-Yuan chiang, Lung-Jen chen, chien-chon Liao, Meng-Hsuan Kuo, Jih-Sheng chou, Ya-Hsuan Natl Taipei Univ Technol Grad Inst Intellectual Property Taipei 10608 Taiwan China Steel Corp Iron & Steel Res & Dev Dept Kaohsiung 81233 Taiwan Natl United Univ Dept Energy Engn Miaoli 36063 Taiwan

The main objective of the present study was to understand the influences of different atomic ratios of Ti/Mo and (Ti + Mo)/c on the precipitation behaviors in Ti-Mo HSLA steels. It was found that the steel with a higher Ti/Mo atomic ratio possessed a large theoretical volume fraction of precipitated carbides, but the ferrite matrix did not achieve a corresponding higher microhardness. On the other hand, the experimental results also indicated that it was not suitable to assess the precipitation strengthening effect of the ferrite matrix based on only one of the atomic factors, i.e., (Ti + Mo)/c or Ti/Mo. In addition, from the present study, similarity of the (Ti + Mo)/c atomic ratios is a prerequisite for comparing the precipitation hardening effects in steels having different Ti/Mo atomic ratios. Besides experimental data, the main deduction is also supported by related patent information, which further corroborates the reliability of the present study. Furthermore, of the two steels with different M/c atomic ratios, the ferrite matrix of the H-(M/c) steel showed a rising trend in Vickers hardness when the isothermal holding time was increased from 5 min to 60 min at 650-700 degrees c. This higher strengthening ability, which occurs within ferrite grains after holding at longer times, can be ascribed to the higher austenite decomposition rate occurring in the H-(M/c) atomic ratio steel. Therefore, the hardening mechanisms in both kinds of steel are also discussed in the present study.

关键词： interphase precipitation precipitation random precipitation Ti Mo (Ti plus Mo) c

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NMR studies of the effects of axial ligand substitution by imidazole on the conformation of cytochrome c

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Science china chemistry 1995年第6期38卷 649-657页

作者：邵伟平姚亦明唐文霞 State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

A series of 1D and 2D 1H NMR studies are presented, which aim at assigning the hyperfine shifted resonances of the heme and the spin systems of more than 20 amino acid side chains, and characterizing the heme and ligand environment of the low spin imidazole complex of cytochrome c. Some details of the structure in the heme pocket of the cytochrome c-imidazole complex are shownqualitatively to have changed relatively to the native oxidized protein. The orientation of the coordinated imidazole is also determined based on the interpretation of a number of NOEs.

关键词： imidazole complex of cytochrome c NMR axial ligand conformation.

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Ti-Fe-Si/c composites as anode materials for high energy li-ion batteries

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ENERGY SOURcES PART A-REcOVERY UTILIZATION AND ENVIRONMENTAL EFFEcTS 2022年第2期44卷 5154-5171页

作者： Nuhu, Bage Alhamdu Adun, Humphrey Bamisile, Olusola Mukhtar, Mustapha Southwest Petr Univ Sch Chem & Chem Engn Chengdu Peoples R China Cyprus Int Univ Energy Syst Engn Dept Mersin 10 Nicosia Turkey Chengdu Univ Technol Coll Nucl Technol & Automat Engn Chengdu Sichuan Peoples R China Guangdong Univ Petrochem Technol Sch Econ & Management Maoming Chinese Provinc Peoples R China

In this study, Ti-Fe-Si composites were prepared by one step ball-milling method as anode materials for Li-ion batteries. The effects of ball-milling speed and time were studied by X-ray diffraction, electron microscopy, and Fe-57 Mossbauer spectroscopy. changes in the composition and microstructure of the composites were observed and related to the electrochemical performance. Increasing ball-milling speed led to the formation of FeSix alloys that reduced the specific capacity while increasing the ball-milling time improved the particle size morphology and homogeneity. Discharge/charge profiles for the first two cycles were carried out at 0.05c current rate (1c = 1260 mAh.g(-1)for Li3.75Si). The first discharge for Ti-Fe-Si showed a LixSi reaction plateau of 1100 mAh.g(-1), which were reversible and yielded columbic efficiency (cE) 77% and 90% in the first and second cycles, respectively. This capacity plateau indicated the insertion of about 3.25 Li into silicon. For the composite containing an additional 10% carbon SP, the theoretical capacity was about 1130 mAh.g(-1), the discharge curve showed that the first discharge plateau reaches 1030 mAh.g(-1) corresponding to 3.5 Li with the first cE was about 85%, and 98% for the second cycle. The addition of carbon to Ti-Fe-Si-c played a key role in capacity retention. The best results were obtained for the composite Fe/Ti/Si (1:1:2) with 10 wt% of carbon, ball-milled at 500 rpm for 48 hours. The specific capacities were about 900 mAh.g(-1) at c/5 and 700 mAh.g(-1) at 1c (c = 1200 mAg(-1)) with a capacity retention of about 90% for 100 cycles.

关键词： Ti-Fe-Si c Li-ion batteries ball milling anode capacity discharge charge

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Oxidation behaviour of Sic ceramic coating for c/c composites prepared by pressure-less reactive sintering in wet oxygen: Experiment and first-principle simulation

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cERAMIcS INTERNATIONAL 2021年第11期47卷 15337-15348页

作者： Zhang, Pengfei Zhang, Yulei Gai, Wenhan chen, Guohui Northwestern Polytech Univ Shaanxi Prov Key Lab Fiber Reinforced Light Compo State Key Lab Solidificat Proc Xian 710072 Peoples R China

Sic ceramic coating, for prevention of c/c composites against oxidation, was prepared by pressure-less reactive sintering to investigate the oxidation behaviour in an oxidising environment containing water vapour at 1773 K. The experimental results demonstrated that the oxidation behaviour of porous Sic ceramics could be divided into two stages, following the parabolic model, which was attributed to the variation in the contact area involved in the oxidation reactions. During the entire oxidation process, water vapour could accelerate the oxidation of the Sic ceramics, according to the weight change. By first-principle calculations, the accelerated oxidation rate of the Sic ceramics was attributed to weakened Si?O and Al?O bonds in the formed glassy scale, which were caused by hydroxide radicals from the water. Atomic thermal motions at high temperature could lead to the breakage of the network structure, promoting the diffusion and solution of oxidising gases. When the as-prepared Sic ceramics were applied as anti-oxidative coatings for the c/c composites, the Sic ceramic coating and c/c matrix could be sealed and protected faster per unit time, because water vapour was beneficial to the formation of a glassy layer. The weight loss of the c/c matrix could be attributed to unsealed microcracks inside the Sic coating in the initial stage.

关键词： c c composites Sic ceramic coating Oxidation behaviour Wet oxygen First-principles Molecular dynamics

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