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Chinese Physics B 2017年第1期26卷 290-297页

作者： Xiao-Yan Sun yu-ru zhang Xue-Chun Li You-Nian Wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams （Ministry of Education） School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 China

Planar radio frequency inductively coupled plasmas（ICP） are employed for low-voltage ion implantation processes,with capacitive pulse biasing of the substrate for modulation of the ion energy. In this work, a two-dimensional（2D） selfconsistent fluid model has been employed to investigate the influence of the pulsed bias power on the nitrogen plasmas for various bias voltages and pulse frequencies. The results indicate that the plasma density as well as the inductive power density increase significantly when the bias voltage varies from 0 V to-4000 V, due to the heating of the capacitive field caused by the bias power. The N＋fraction increases rapidly to a maximum at the beginning of the power-on time, and then it decreases and reaches the steady state at the end of the glow period. Moreover, it increases with the bias voltage during the power-on time, whereas the N2-＋ fraction exhibits a reverse behavior. When the pulse frequency increases to 25 kHz and40 kHz, the plasma steady state cannot be obtained, and a rapid decrease of the ion density at the substrate surface at the beginning of the glow period is observed.

关键词： fluid simulation low-voltage plasma immersion ion implantation N2 inductive discharge

Numerical investigation of radio-frequency negative hydrogen ion sources by a three-dimensional fluid model

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Chinese Physics B 2021年第9期30卷 335-345页

作者： Ying-Jie Wang Jia-Wei Huang Quan-Zhi zhang yu-ru zhang Fei Gao You-Nian Wang Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China

A three-dimensional fluid model is developed to investigate the radio-frequency inductively coupled H2 plasma in a reactor with a rectangular expansion chamber and a cylindrical driver chamber,for neutral beam injection system in *** this model,the electron effective collision frequency and the ion mobility at high E-fields are employed,for accurate simulation of discharges at low pressures(0.3 Pa-2 Pa)and high powers(40 kW-100 kW).The results indicate that when the high E-field ion mobility is taken into account,the electron density is about four times higher than the value in the low E-field *** addition,the influences of the magnetic field,pressure and power on the electron density and electron temperature are *** is found that the electron density and electron temperature in the xz-plane along permanent magnet side become much more asymmetric when magnetic field ***,the plasma parameters in the yz-plane without permanent magnet side are symmetric no matter the magnetic field is applied or ***,the maximum of the electron density first increases and then decreases with magnetic field,while the electron temperature at the bottom of the expansion region first decreases and then almost keeps *** the pressure increases from 0.3 Pa to 2 Pa,the electron density becomes higher,with the maximum moving upwards to the driver region,and the symmetry of the electron temperature in the xz-plane becomes much *** power increases,the electron density rises,whereas the spatial distribution is *** can be summarized that the magnetic field and gas pressure have great influence on the symmetry of the plasma parameters,while the power only has little effect.

关键词： negative hydrogen ion source inductively coupled plasma three-dimensional fluid model magnetic field effect

Fundamental study towards a better understanding of low pressure radio-frequency plasmas for industrial applications

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Chinese Physics B 2022年第8期31卷 14-36页

作者： Yong-Xin Liu Quan-Zhi zhang Kai Zhao yu-ru zhang Fei Gao yuan-Hong Song You-Nian Wang Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China

Two classic radio-frequency(RF) plasmas, i.e., the capacitively and the inductively coupled plasmas(CCP and ICP),are widely employed in material processing, e.g., etching and thin film deposition, etc. Since RF plasmas are usually operated in particular circumstances, e.g., low pressures(m Torr-Torr), high-frequency electric field(13.56 MHz-200 MHz),reactive feedstock gases, diverse reactor configurations, etc., a variety of physical phenomena, e.g., electron resonance heating, discharge mode transitions, striated structures, standing wave effects, etc., arise. These physical effects could significantly influence plasma-based material processing. Therefore, understanding the fundamental processes of RF plasma is not only of fundamental interest, but also of practical significance for the improvement of the performance of the plasma sources. In this article, we review the major progresses that have been achieved in the fundamental study on the RF plasmas,and the topics include 1) electron heating mechanism, 2) plasma operation mode, 3) pulse modulated plasma, and 4) electromagnetic effects. These topics cover the typical issues in RF plasma field, ranging from fundamental to application.

关键词： RF plasma electron heating discharge mode pulse modulation electromagnetic effects

Effect of radio frequency bias on plasma characteristics of inductively coupled argon discharge based on fluid simulations

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Chinese Physics B 2020年第9期29卷 369-376页

作者： Xiao-Yan Sun yu-ru zhang Sen Chai You-Nian Wang Yan-Yan Chu Jian-Xin He Textile and Garment Industry of Research Institute Zhongyuan University of TechnologyZhengzhou 450007China Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China China Special Equipment Inspection and Research Institute Beijing 100029China

t A fluid model is employed to investigate the effect of radio frequency bias on the behavior of an argon inductively coupled plasma(ICP).In particular,the effects of ICP source power,single-frequency bias power,and dual-frequency bias power on the characteristics of ICP are simulated at a fixed pressure of 30 mTorr(1 Torr=1.33322×102 Pa).When the bias frequency is fixed at 27.12 MHz,the two-dimensional(2D)plasma density profile is significantly affected by the bias power at low ICP source power(e.g.,50 W),whereas it is weakly affected by the bias power at higher ICP source power(e.g.,100 W).When dual-frequency(27.12 MHz/2.26 MHz)bias is applied and the sum of bias powers is fixed at 500 W,a pronounced increase in the maximum argon ion density is observed with the increase of the bias power ratio in the absence of ICP source *** the ratio of 27.12-MHz/2.26-MHz bias power decreases from 500 W/0 W to 0 W/500 W with the ICP source power fixed at 50 W,the plasma density profiles smoothly shifts from edge-high to center-high,and the effect of bias power on the plasma distribution becomes weaker with the bias power ratio ***,the axial ion flux at the substrate surface is characterized by a maximum at the edge of the *** the ICP source power is higher,the 2D plasma density profiles,as well as the spatiotemporal and radial distributions of ion flux at the substrate surface are characterized by a peak in the reactor center,and the distributions of plasma parameters are negligibly affected by the dual-frequency bias power ratio.

关键词： fluid simulation single-and dual-frequency bias power plasma distribution

MOLECULAR STruCTURE OF 2-[BIS(2-CHLOROETHYL)-AMINO]-6-BUTYLOXYMETHYL-TETRAHYDRO-2H-1, 3,2-OXA-ZAPHOSPHORINE-2-OXIDE

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Chinese Journal of Structural Chemistry 1993年第4期 303-306页

作者： Chen ru-yu zhang MingInstitute of Elemento-Organic Chemistry,Nankai University,Tianjin,300071Wang ru-Ji Wang Hong-GenCentral Laboratory,Nankai University,Tianjin,300071

The molecular structure of 2-[bis(2-chloroethyl)-amino]-6-t-butyloxymethyl-tetrahydro-2H-1,3,2-oxazaphosphorine-2-oxide has been determined by X-ray diffraction *** crystal(C12H25Cl2NaO3P)is monoclinic with space group P21/a,a=11.965(2),b=10.335(3),c=14.543(5)A,β=102.24(2)°,V=1758(2)A3,Mr=347.22,Z=4,Dx=1.31 g/cm3,μ=4.66 cm-1,F(000)=736,R=0.051,Rw=*** six-membered ring in this compound is in a distorted chair conformation with the t-butyloxymethyl group and the phosphoryl oxygen atom in equatorial positions which lead to cis-configuration.

关键词： BIS OXA-ZAPHOSPHORINE-2-OXIDE AMINO BUTYLOXYMETHYL-TETRAHYDRO-2H-1 CHLOROETHYL MOLECULAR STruCTURE OF 2

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人手抓持识别与灵巧手的抓持规划

机器人 2002年第6期24卷 530-534页

作者：李继婷张玉茹张启先北京航空航天大学机器人研究所 100083

本文研究灵巧手采用指尖抓持方式时的抓持规划方法 .在相同的操作环境和操作对象下 ,由人手决定抓持接触点的位置 ,利用人手运动测量装置测量人手抓持位置 ,通过一定的映射关系将其转换为灵巧手的抓持位置及其掌系的位姿。

关键词：灵巧手人手抓持运动学

Effect of urotensin-II on intracellular free calcium concentration in rats cultured hippocampal neurons

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Effect of urotensin-II on intracellular free calcium concent...

中国生理学会第五届全国心血管、呼吸和肾脏生理学学术会

作者： Wu yu-ming, Wang ru, zhang Hao, He rui-rong (Department of physiology, Hebei medical university, shijiazhuang 050017)

来源： cnki会议评论

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一类Power抓持接触力分解的一般表达式

机器人 1999年第6期21卷 407-414页

作者：李剑锋张玉茹张启先北京航空航天大学机器人研究所北京100083

与灵巧抓持相比，Ｐｏｗｅｒ抓持可承受较大的外部载荷，能够更稳定地抓持物体．但由于抓持机构与物体间的约束较多，且接触点可出现在抓持机构中活动度有限的构件上，因此不能采用已有的适用于灵巧抓持的接触力分解方法对其接触力进行... 详细信息

与灵巧抓持相比，Ｐｏｗｅｒ抓持可承受较大的外部载荷，能够更稳定地抓持物体．但由于抓持机构与物体间的约束较多，且接触点可出现在抓持机构中活动度有限的构件上，因此不能采用已有的适用于灵巧抓持的接触力分解方法对其接触力进行分解．本文在对一类Ｐｏｗｅｒ抓持机构的结构特征进行分析的基础上，适当地建立了接触坐标系和物体坐标系．通过对接触力空间进行分解，给出了抓持接触力分解的一般表达式．并根据该表达式，建立了此类Ｐｏｗ

关键词： Power抓持接触力分解一般表达式

Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao zhang Zhanyu Li Yijia Lei Baozeng Sun Xiaoyu yu Zhe Wang College of Chemistry and Life Science Changchun University of Technology College of Chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional Polymer Membrane Materials of Jilin Province

The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that PTI-PTF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of *** cell polarization curve based on PTI-PTF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： Anion exchange membranes Poly(p-terphenylene isatin) Hydrophilic-hydrophobic phase separation Fluorinated group

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo yu Zhenyu Sun Weichen Zheng Liangwei zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment