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Influence of nitrogen implantation into HSS substrate on internal stress and adhesion strength of c-BN films

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 286-290页

作者： zhang ping cai Zhi-hai TAN Jun XIONG Wan-quan National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

Cubic boron nitride(c-BN) films were deposited on HSS substrate implanted with nitrogen ion by RF-magnetron sputtering. The films were analyzed by bending beam method, scratch test, XRD and AFM. The results show that the implantation of N ion can reduce the internal stress and improve the adhesion strength of the *** critical load comes to 16.92N, compared to 1.75N of c-BN film on the unimplanted HSS. AFM shows that the surface of the c-BN film on the implanted HSS is low in roughness and small in grain size. The phase structure of the nitrogen implanted layer was analyzed by XRD. The influence of nitrogen implanted layer on the internal stress and adhesion strength of c-BN films were also investigated.

关键词： cubic boron nitride film HSS ion implantation internal stress adhesion

Dynamics and Thermodynamics of Porous HMX-like Material Under Shock

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Communications in Theoretical Physics 2009年第11期52卷 901-908页

作者： XU Ai-Guo zhang Guang-cai zhang ping PAN Xiao-Fei ZHU Jian-Shi National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009-26 Beijing 100088 China

Strong shock may induce complex processes in porous materials. We use the newly developed materialpoint-method to simulate such processes in an HMX-like material. To pick out relevant information, morphological characterization is used to treat with the temperature map. Via the Minkowski funetional analysis the dynamics and thermodynamics of the shock wave reaction on porous HMX-like material are studied. The geometrical and topological properties of the ＂hot-spots＂ are revealed. Numerical results indicate that, shocks in porous materials are not simple jump states as classically viewed, but rather are a complex sequence of compressions and rarefactions. They cover a broad spectrum of states. We can use coarse-grained description to the wave series. A threshold value of temperature presents a Turing pattern dynamical procedure. A higher porosity is generally preferred when the energetic material needs a higher temperature for initiation. The technique of data analysis can be used to other physical quantities, for example, density, particle velocity, some specific stress, etc. From a series of studies along the line, one may get a large quantity of information for desiring the fabrication of material and choosing shock strength according to what needed is scattered or connected ＂hot-spots＂. PACS numbers： ***, 05 Key words： porous material 70.-a, 05.40.-a, *** shock wave, Minkowski functionals

关键词： porous material shock wave Minkowski functionals

Farmers' seed choice behaviors under asymmetrical information: Evidence from maize farming in China

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Journal of Integrative Agriculture 2016年第8期15卷 1915-1923页

作者： QIU Huan-guang WANG Xiao-bing zhang cai-ping XU Zhi-gang School of Agricultural Economics and Rural Development Renmin University of China Center for Chinese Agricultural Policy Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences China's Center for Agricultural Policy School of Advanced Agricultural Sciences Peking University School of Economics Central University of Finance and Economics College of Economics and Management Nanjing Agricultural University

the financial support of the National Social Science Foundation of China （14ZDA038）;the National Natural Science Foundation of China （71222302;71373255;71573133）;the Institute of Geographic Sciences and Natural Re... 详细信息

关键词： new technology adoption seed portfolio asymmetrical information maize

Investigation of electron localization in harmonic emission from asymmetric molecular ion

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Chinese Physics B 2015年第4期24卷 154-161页

作者：张彩萍苗向阳 College of Physics and Information Engineering Shanxi Normal University

We theoretically investigate the electron localization around two nuclei in harmonic emission from asymmetric molecular ion. The results show that the ionization process of electron localized around one nucleus competes with its transfer process to the other nucleus. By increasing the initial vibrational level, more electrons localized around the nucleus D＋ tend to transfer to the nucleus He2＋ so that the ionizations of electrons localized around the nucleus He2＋ increase. In this case, the difference in harmonic efficiency between Hell2＋ and HeD2＋ decreases while the difference in harmonic spectral structure increases. The evident minimum can be observed the spectral structure of HeD2＋, which is due to the strong in the harmonic spectrum of Hell2＋ compared with that in interference of multiple recombination channels originating from two nuclei. Time-dependent nuclear probability density, electron-nuclear probability density, double-well model, and time-frequency maps are presented to explain the underlying mechanisms.

关键词： high-order harmonic generation asymmetric molecular ion vibrational state electron localization

Battery Management System Used in Electric Vehicles

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电力电子技术 2011年第12期45卷 2-10页

作者： JIANG Jiu-chun WEN Feng WEN Jia-peng zhang cai-ping School of Electrical Engineering Beijing Jiaotong University Beijing 100044 China

A battery management system(BMS) which contains state of charge(SOC) determination,battery charging control and its optimization,and cell balancing is ***'s model having a RC network characterizing the battery polarization is used for SOC *** polarization voltage of the battery model is identified using the nonlinear least square *** paper presents a new SOC definition method considering the SOC limit of each cell for battery pack in *** relationship between the battery current and polarization voltage is *** then the battery charging approach that the charging current can be adaptively adjusted by the polarization voltage control system is investigated based on fuzzy logic control *** balancing control strategy is also proposed based on the principle of the maximum use for the capacity and energy of the battery pack.

关键词：《电力电子技术》期刊摘要编辑部

Preparation and Magnetic Properties of Submicron CrO2 Thin Film on Poly-crystal TiO2 Film

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Chemical Research in Chinese Universities 2013年第3期29卷 600-602页

作者： YUAN Ju-jun WEN Ge-hui ZHAO Qiang FAN Yin-bo zhang cai-ping zhang Xian-ke YU Hua-jun XIE Ying-mao College of Physics and Electronics Gannan Normal University Ganzhou 341000 P. R. China State Key Laboratory of Superhard Materials Jilin University Changchun 130012 P. R. China Institute of Optoelectronic Materials and Technology Gannan Normal University Ganzhou 341000 P. R. China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 P. R. China

The submicron chromium dioxide（CrO2） thin film was fabricated on a poly-crystal titania（TiO2） film using Si wafers as substrates by atmospheric pressure chemical vapor deposition（CVD） method. X-Ray diffraction patterns show that the CrO2 films were pure rutile structure. Scanning electron microscopy（SEM） images indicate that the CrO2 films consisted of submicron grains with a grain size of 250--750 rim. The magnetic researches reveal that the magnetic easy axis is parallel to the films, and at room temperature, the CrO2 films show linear magnetoresistance.

关键词： CrO2 film TiO2 film Chemical vapor deposition(CVD) Magnetic property Half-metal ferromagnet

Synthesis and Magnetotransport Properties of CrO_(2)-TiO_(2) Composites

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Chinese Physics Letters 2013年第3期30卷 154-157页

作者： FAN Yin-Bo zhang cai-ping DU Xiao-Bo WEN Ge-Hui MA Hong-An JIA Xiao-Peng State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012 College of Physics Jilin UniversityChangchun 130012

CrO_(2)-TiO_(2) composites are synthesized by using a high temperature and high pressure method using CrO_(3) and H_(2)TiO_(3) as *** composites consist of large rod-like CrO_(2) crystals separated by small TiO_(2) *** CrO_(2) in the composites is very pure and its saturation magnetization is very close to the theoretical value(i.e.,2μ_(B) per formula unit).The composites exhibit a large negative magnetoresistance(MR)at 5 *** MR in CrO_(2)-TiO_(2) composites is mainly attributed to spin-polarized tunneling between CrO_(2) *** conductivity of the composites is best described by a fluctuation-induced tunneling model below 230 K.

关键词： composites CrO2 tunneling

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG ping GUAN Chi zhang Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

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碳排放权初始会计确认问题研究

上海立信会计学院学报 2011年第4期25卷 34-43页

作者：张彩平南华大学经济管理学院湖南衡阳421001

综述碳排放权会计确认的研究现状可知,不同的组织和学者从不同角度将碳排放权确认为不同的资产类别,从而导致了碳排放权会计确认的多元化,并削弱了碳排放权会计信息的可比性。为了解决这一难题,应从全新的角度认识碳排放权的本质。研究... 详细信息

综述碳排放权会计确认的研究现状可知,不同的组织和学者从不同角度将碳排放权确认为不同的资产类别,从而导致了碳排放权会计确认的多元化,并削弱了碳排放权会计信息的可比性。为了解决这一难题,应从全新的角度认识碳排放权的本质。研究结果表明,碳排放权的货币属性比商品属性更能反映碳排放权的本质,不仅与碳排放权交易制度制定和实施的目的实现了内在一致性,而且实现了减排经济效益和环境效益的有机统一。同时,从会计核算的角度来看,碳排放权的货币确认避免了项目型和配额型这两种不同的碳排放权交易制度下会计确认的复杂性,碳排放权应初始确认为"碳货币"。

关键词：碳排放权初始会计确认商品属性货币属性碳货币