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Comparative studies of adsorbed CO and methanol electrooxidation on carbon supported Pt and PtRu catalysts in acid solution

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Rare Metals 2006年第3期25卷 274-280页

作者： PENG cheng ZHANG Zhen cheng Xuan ZHANG ying Department of Applied chemistry South China University of Technology Guangzhou 510641 China Department of chemistry State Key Laboratory for Physical Chemistry of Solid Surfaces Xiamen University Xiamen 361005 China Department of Materials Science and Engineering Xiamen University Xiamen 361005 China

Physicochemical characterization of commercial Pt/C and PtRu/C catalysts was carried out by X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. Comparative studies of methanol electrooxidation on carbon supported Pt and PtRu catalysts in acid solution were performed by means of an electrochemical method. The experimental results showed that PtRu/C not only had a higher electrocatalytic activity for the electrocatalytic oxidation of methanol than Pt/C, but also for the electrocatalytic oxidation of adsorbed CO. Alloy formation of Ru with Pt modified not only the characteristics of H2 adsorption on the surface of catalyst but also the characteristics of CO adsorption on the sur face of catalyst. The interaction of CHaOH with Ru was a temperature-activated process requiring elevated temperature.

关键词： electrochemistry methanol oxidation cyclic voltammetry electrocatalyst

Fruit fly research in China

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Journal of Genetics and Genomics 2018年第11期45卷 583-592页

作者： ying cheng Dahua chen State Key Laboratory of Membrane Biology Institute of Zoology Chinese Academy of Sciences

Served as a model organism over a century, fruit fly has significantly pushed forward the development of global scientific research, including in China. The high similarity in genomic features between fruit fly and human enables this tiny insect to benefit the biomedical studies of human diseases. In the past decades, Chinese biologists have used fruit fly to make numerous achievements on understanding the fundamental questions in many diverse areas of biology. Here, we review some of the recent fruit fly studies in China, and mainly focus on those studies in the fields of stem cell biology, cancer therapy and regeneration medicine, neurological disorders and epigenetics.

关键词： China Development Epigenetics Fruit fly Genetics Neurology Signaling pathway

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan Zhang Xiaomin cheng Qinghua Guan Jing Dong Bixian chen Lujie Jia Jing Zhang Yongzheng Zhang Yunjian Liu Hongzhen Lin School of Materials Science and Engineering Jiangsu University i-Lab & CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZMBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition

Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science China chemistry 2025年第1期 181-185页

作者： Yanping Xia Luyang Sun Jiajia cheng Sibo Wang Meifang Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

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Perspectives on relativistic quantum chaos

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Communications in Theoretical Physics 2020年第4期72卷 112-137页

作者： Liang Huang ying-cheng Lai School of Physical Science and Technology and Key Laboratory for Magnetism and Magnetic Materials of MOELanzhou UniversityLanzhouGansu 730000China School of Electrical Computerand Energy EngineeringArizona State UniversityTempeAZ 85287United States of America Department of Physics Arizona State UniversityTempeAZ 85287United States of America

Quantum Chaos has been investigated for about a half *** is an old yet vigorous interdisciplinary field with new concepts and interesting topics emerging *** years have witnessed a growing interest in quantum chaos in relativistic quantum systems,leading to the still developing field of relativistic quantum *** purpose of this paper is not to provide a thorough review of this area,but rather to outline the basics and introduce the key concepts and methods in a concise way.A few representative topics are discussed,which may help the readers to quickly grasp the essentials of relativistic quantum chaos.A brief overview of the general topics in quantum chaos has also been provided with rich references.

关键词： quantum chaos relativistic quantum systems Dirac billiards

Experimental Analysis of Microscale Laser Shock Processing on Metallic Material Using Excimer Laser

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Journal of Materials Science & Technology 2009年第6期25卷 829-834页

作者： Zhigang che Liangcai Xiong Tielin Shi Huayang cheng Likun Yang Wuhan National Laboratory for Optoelectronics State Key Lab of Digital Manufacturing Equipment & Technology School of Mechanical Science and Engineering Huazhong University of Science & Technology Wuhan 430074 China Wuhan Huagong Laser Engineering Co. Ltd Wuhan 430223 China

Microscale laser shock processing （μLSP）, also known as laser shock processing in microscale, is a technique that uses microscale focused laser beam to induce high pressure plasma and generates plastic deformation and compressive residual stress in target materials, thus improves fatigue or stress corrosion cracking resistance of MEMS （Micro Electromechanical Systems） devices made of such a material. Many works have been reported about the research and experiment for μLSP. But the diameters of 50-200 μm were used at the first time for this field, which was useful for treating micro-device components with larger area and curved surface. The excimer laser was used firstly on μLSP for shorter wavelength than that of used in previous researches. The determination method of laser spot size at micro-level spatial resolution was presented. Under these conditions, plastic deformation, the stress analysis and microhardness with different pulse number, pulse energy and pulse spacing were investigated. Especially the residual stress distribution with depth treated by #LSP, was first investigated. Experiment results showed that the material performance was improved remarkably after μLSP.

关键词： μLSP Plastic deformation Residual stress Micro-hardness Laser spot size

Scattering for the Radial Schrodinger Equation with Combined Power-type and Choquard-type Nonlinearities

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1029-1041页

作者： ying WANG cheng Bin XU The Graduate School of China Academy of Engineering Physics Beijing 100088P.R.China School of Mathematics and Statistics Qinghai Normal UniversityXining 810008P.R.China

In this paper,we show the scattering of the radial solution for the nonlinear Schrodinger equation with combined power-type and Choquard-type nonlinearities iut+△u=λ1|u|p1-1u+λ2(Iα*|u|^(p2))|u|p^(2-2)*** the energy space H^(1)(R^(N))forλ_(1)λ_(2)=-*** establish a scattering criterion for radial solution together with Morawetz estimate which implies the scattering *** show that the defocusing perturbation terms does not determine the scattering solution in energy space.

关键词： Schrodinger equation Choquard-type Scattering theory

3D trajectory inversion of an adjacent well using scattered P-wave

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Petroleum Science 2023年第2期20卷 857-865页

作者： Lu cheng Xiao-Hua che Wen-Xiao Qiao Teng Zhao State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Key Laboratory of Earth Prospecting and Information Technology Beijing102249China

In oil and gas exploitation,cluster well technology can significantly reduce costs and improve *** effective adjacent well detection method can greatly reduce the risk of collision between adjacent *** study proposes a method to invert the 3D trajectory of an adjacent well using a scattered P-wave obtained by borehole azimuthal acoustic reflection *** obtaining the scattered P-wave from the raw data of the target well using the wave field separation technology,the waveform data in an imaging profile can be obtained by the downhole acoustic directional reception *** imaging technology is then used to obtain the image of the formation in the imaging ***,by analyzing the images of the formation in the imaging profile of the different azimuths,the well spacing and azimuth of the target well can be ***,the 3D trajectory of the target well can be obtained by solving the inversion *** method was validated by processing the field data from a deviated well in a deep *** comparison of the inversion and actual trajectories of the target well demonstrated that the maximum deviation of the inversion trajectory is 0.9 m in the north-south direction,0.78 m in the east-west direction,1.45 m in the well spacing,and 2.48°in the *** field data inversion result demonstrated that the method can effectively use the azimuth reflection acoustic data to invert the 3D trajectory of an adjacent well,which indicates that the borehole azimuthal acoustic reflection imaging technology has great potential within the context of adjacent well detection.

关键词： Acoustic imaging Acoustic reflection logging Directional reception Adjacent well

Matched glass-to-Kovar seals in N_2 and Ar atmospheres

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 874-882页

作者： cheng-hsien Kuo Pi-ying cheng Chang-pin Chou Department of Mechanical Engineering Chiao Tung University

The oxidation of Kovar alloy was investigated, the wetting and spreading behavior of hard and soft glasses on Kovar alloy were studed by using the sessile drop method, and the quality and the seal strength of glass-Kovar seals were tested. The experimental results indicated that the preoxidation of Kovar alloy for approximately 10 min at 700℃ in air resulted in excellent adherence in glass-Kovar seals. The wetting and spreading behavior of glass on preoxidized Kovar alloy were superior to that on nonoxidized Kovar alloy. The wetting ability of ASF110 glass, at 950℃ and 980℃ in Ar and N2 atmospheres, was significantly superior to that of ASF200R and ASF700 glasses. The seal quality of the glass-preoxidized Kovar seal was superior to that of the glass-nonoxidized Kovar seal. The shear strength of the ASFll0 glass-preoxidized Kovar seal, which was prepared at 980℃ for 20 min in an Ar atmosphere, was approximately 3.9 MPa.

关键词： Kovar alloy glass sealing argon nitrogen oxidation wetting