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Preparation of a Pt-Ni_(2)P/NF catalyst for highly efficient hydrogen evolution using a magnetic field to promote Ni-Pt galvanic replacement

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Journal of Materials Science & Technology 2023年第11期142卷 144-151页

作者： zhong wang Shuang Yuan Tuo Zang Tengxiao Li Yudi Zhou Jiaqi Liu Tie Liu Kai wang Qiang wang School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China Institute for Frontier Technologies of Low-Carbon Steelmaking and Liaoning Province Engineering Research Center for Technologies of Low-Carbon Steelmaking Northeastern UniversityShenyang 110819China The State Key Lab of Rolling and Automation Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education)(Ministry of Education) Northeastern UniversityShenyang 110819China

The noble metal Pt is an ideal catalyst for promoting the hydrogen evolution reaction(HER)during the electrolysis of ***,Pt is also expensive and suffers from low utilization *** this work,a Pt-Ni_(2)P/NF nanorod catalyst with a low Pt loading was synthesized under different magnetic fields,and it was found that the application of a magnetic field can increase the rate of the galvanic replacement *** the magnetic field strength increases from 0 to 600 mT,the chemical reaction rate increases gradually,and the utilization rate of Pt increased by 2.3 times under 600 *** mechanism of the magnetic field-induced magnetohydrodynamic(MHD)effect on the galvanic replacement reaction was *** a 1 M KOH solution and at a current density of 10 mA cm^(-2),the overpotential of Pt-Ni_(2)P/NF prepared by applying a 600 mT magnetic field was as low as 15 mV and the Tafel slope was 37 mV dec^(-1),compared with values of 82 mV and 70 mV dec^(-1) for a specimen prepared without a magnetic ***,at an overpotential of 90 mV,the mass-based Pt activity of the former material was 12 times greater while its turnover frequency was 19 times *** work provides theoretical and technical knowledge expected to assist in the controllable preparation of materials in magnetic fields and the efficient utilization of metallic resources.

关键词： Magnetic field Regulation Galvanic replacement reaction HER

Some generalized limit theorems concerning delayed sums of random sequence

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 40-48页

作者： wang zhong-zhi YANG Wei-guo SHI Zhi-yan School of Mathematics & Physics AnHui University of Technology Faculty of Science Jiangsu University

For a sequence of arbitrarily dependent m-valued random variables （Xn） n∈N , the generalized strong limit theorem of the delayed average is investigated. In our proof, we improved the method proposed by Liu [6] . A... 详细信息

关键词： Limit theorem delayed average Borel-Cantelli lemma inhomogeneous Markov chain.

Thermotolerant and fireproof gel polymer electrolyte toward high-performance and safe lithium-ion battery

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Journal of Energy Chemistry 2022年第2期31卷 9-18页

作者： Man-Cheng Long Ting wang Ping-Hui Duan You Gao Xiu-Li wang Gang Wu Yu-zhong wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

Poly(ethylene oxide)(PEO)and its derivatives based gel polymer electrolytes(GPEs)are severely limited in advanced and safe lithium-ion batteries(LIBs)owing to the intrinsically high flammability of liquid electrolytes and *** adding flame retardants to the GPEs can suppress their flammability and thus improve the safety of LIBs,but results in deteriorative electrochemical ***,a novel GPE with chemically bonded flame retardant(*** vinylphosphonate)in cross-linked polyethylene glycol diacrylate matrix,featuring both high-safety and high-performance,is *** as-prepared GPE storing the commercial 1 mol L^(-1) LiPF6 electrolyte resists high temperature of 200℃and cannot be ignited as well as possesses a high ionic conductivity(0.60 m S cm^(-1))and good compatibility with ***,the LiFePO_(4)/Li battery with this GPE delivers a satisfactory capacity of 142.2 m A h g^(-1) and a superior cycling performance with a capacity retention of 96.3%and a coulombic efficiency of close to 100%for 350 cycles at 0.2 C under ambient ***,the battery can achieve steady charge–discharge for 100 cycles with a coulombic efficiency of 99.5%at 1 C under 80℃and run normally even at a high temperature of 150℃or under the exposure to butane *** scanning calorimetry manifests significantly improved battery safety compared to commercial battery *** work provides a new pathway for developing next-generation advanced LIBs with enhanced performance and high safety.

关键词： Gel polymer electrolyte Poly(ethylene oxide) Flame retardant Vinylphosphonate Lithium-ion batteries

Spatial Distribution of Soil Erosion Sensitivity on the Tibet Plateau

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Pedosphere 2005年第4期15卷 465-472页

作者： wang Xiao-Dan zhong Xiang-Hao FAN Jian-Rong Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 （China）

The Tibet Plateau, occupying the main part of Qinghai-Tibet Plateau and having an average altitude of 4 500 m, has geomorphological features that are unique in the world, with soil erosion being one of the main ecological problems. Thus the main objectives of the present research were to set up an efficient and simple way of evaluating spatial distribution of soil erosion sensitivity in the Tibet Plateau as well as the responses of soil erosion to changes of natural environmental conditions, and to indicate key regions where soil erosion should be preferentially controlled. Based on the Universal Soil Loss Equation (USLE), the study applied geographic information system (GIS) technology to develop a methodological reference framework, from which soil erosion sensitivity could be evaluated. The impact of precipitation, soil, topography and vegetation on soil erosion was divided into classes of extreme sensitivity, high sensitivity, medium sensitivity, low sensitivity and no sensitivity. With the aid of GIS, the resultant map from overlaying various factors showed that soil erosion sensitivity had great discrepancy in different parts of the region. In the southeastern part of the Tibet Plateau there were mainly three classes of sensitivity, namely, extreme, high and medium sensitivity. However, the other two classes, low and no sensitivity, were dominant in the northwestern part.

关键词： GIS soil erosion sensitivity spatial distribution Tibet Plateau

An Affirmative Result of the Open Question on Determining Function Jumps by Spline Wavelets

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Acta Mathematica Sinica,English Series 2018年第5期34卷 921-932页

作者： Hai Ying ZHANG Xian Liang SHI Jian zhong wang Science of College Hangzhou Dianzi University Hangzhou 310018 P. R. China College of Mathematics and Computer Science Hu'nan Normal University Changsha 410081 P. R. China Department of Mathematics and Statistics Sam Houston State University Huntsville TX 77341 USA

We study the open question on determination of jumps for functions raised by Shi and Hu in 2009. An affirmative answer is given for the case that spline-wavelet series are used to approximate the functions.

关键词： Jump B-spline wavelets

A Facile Method for Synthesizing TiO_(2) Sea-Urchin-Like Structures and Their Applications in Solar Energy Harvesting

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Chinese Physics Letters 2011年第7期28卷 301-304页

作者： wang Wen-Hui wang Wen-zhong XU Hong-Xing Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 College of Science Minzu University of ChinaBeijing 100081

We present a new method to prepare TiO_(2) sea−urchin-like structures,which involves the initial formation of tubular nanostructures and subsequent self-assembly of the nanotubes into micrometer-scale sea-urchin-like *** also investigate the important role of alkali aqueous conditions in the preparation of TiO_(2) sea−urchin-like *** facile and cost-effective approach provides a new route for the preparation of self-assembled TiO_(2) *** addition,the performance of the as−synthesized TiO2 sea-urchin-like structures as the active layer of an efficient solar energy harvester is also studied and discussed.

关键词： alkali subsequent preparation

Synthesis and characterization of yttrium hydroxide and oxide microtubes

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Rare Metals 2009年第5期28卷 445-448页

作者： wang Shijin zhong Shengliang WEN Zubiao wang Yuling wang Shangping CHEN Jianjun XU Rong LUO Longfei College of Chemistry and Chemical Engineering Jiangxi Normal University Nanchang 330022 China

Hexagonal microtubes with hexagonal phase Y（OH）3 were successfully synthesized by a facile solvothermal method at 160°C for 12 h in the absence of surfactants or templates via a crystal transformation route. Scanning electron microscopy （SEM） results demonstrate that the prepared hexagonal microtubes are with a wall thickness of 50-100 nm, an outer diameter of 1 μm, and lengths going up tens of micrometers. Cubic phase Y2O3 microtubes were obtained after thermal treatment of the Y（OH）3 microtubes at 700 oC for 4 h. Eu^3＋-doped Y2O3 microtubes with strong red emission at 610 nm were also prepared and their photoluminescence （PL） properties were studied. The possible mechanism for the formation of the microtubes was briefly discussed.

关键词： inorganic compounds chemical synthesis luminescence microstructure

Method Based on Time Randomization to Resist Fault Sensitivity Analysis

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Journal of Beijing Institute of Technology 2017年第3期26卷 411-417页

作者： Yingjian Yan Jijun Xu Shoucheng wang zhong wang Min Liu Institute of Information Science and Technology Zhengzhou 450001China

A fault sensitivity analysis（FSA）-resistance model based on time randomization is *** randomization unit is composed of two parts,namely the configurable register array（R-A）and the decoder（chiefly random number generator,RNG）.In this way,registers chosen can be either valid or invalid depending on the configuration information generated by the ***,the fault sensitivity information can be ***,based on this model,a defensive scheme is designed to resist both fault sensitivity analysis（FSA）and differential power analysis（DPA）.This scheme is verified with our experiments.

关键词： block cipher time randomization fault sensitivity analysis (FSA) differential power a-nalysis

The Establishment and Analysis of the Structural-Electromagnetic Coupling Model of the Electrostatically Controlled Deployable Membrane Antenna

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Chinese Journal of Electronics 2024年第2期33卷 479-487页

作者： Shunji ZHANG Yongzhen GU wang zhong Qinggang ZHANG Qingdao University of Science and Technology Key Laboratory of Electronic Equipment Structure Design of Ministry of Education Xidian University

A new structural-electromagnetic coupling(SEC) analysis based on quadratic elements is proposed to solve the mismatch problem between structural elements and electromagnetic grids of the electrostatically controlled deployable membrane antenna(ECDMA). Firstly, the ECDMA reflector surface is meshed and redefined by a series of quadratic elements. Without grid transformation, the calculating formulas for the far-field pattern of ECDMA are derived by the physical-optics method. Then the structural deformation of ECDMA is analyzed and the far-field pattern calculating formulas including deformation errors are developed. Simulation and experiment results show that the quadratic elements are effective and efficient in SEC analysis of the ECDMA, moreover, the electromagnetic grid size demand and the grid discretization error are reduced greatly.

关键词： Couplings Electrodes Analytical models Deformation Electromagnetic fields Electromagnetics Optimization