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Formation of Carbon Nitride Films by Nitrogen Ion Bombardment on C_(60) Films

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Chinese Physics Letters 1996年第9期13卷 714-717页

作者： ren Zhong-min DU Yuan-cheng YING Zhi-feng LI Fu-ming lin Jing ren Yun-zhu ZONG Xiang-fu Department of Physics Fudan UniversityState Key Joint Laboratory for Materials Modification by LaserIonand Electron BeamsShanghai 200433 Institute of Materials Science Fudan UniversityShanghai 200433

The synthesis of covalent carbon nitride films becomes an important subject in the materials research *** a new synthetic method two low-energy(400 and 1000eV)nitrogen ion beams are used to bombard on C_(60) thin films *** bombarded films are used for Raman and x-ray photoelectron spectroscopy(XPS)*** results of the analyses show that under the bombardment of 400eV nitrogen ion beam,the film still contains a large amount of undestructed C_(60) *** the case of l000eV bombardment,only a little amount of C_(60) molecules is kept *** experimental results also show that the destructed carbon species will combine chemically with nitrogen ions to form stable covalent carbon nitride,confirmed by the Raman peaks of,e.g.,*** XPS Nls and Cls lines also indicate the formation of covalent carbon nitride in the bombarded films.

关键词： field carbon chemically

A Novel Simple Visual Tracking Algorithm Based on Hashing and Deep Learning

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Chinese Journal of Electronics 2017年第5期26卷 1073-1078页

作者： zhu Suguo DU Junping ren Nan Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia School of Computer ScienceBeijing University of Posts and Telecommunications

Deep network has been proven efficient and robust to capture object features in some *** still remains in the stage of classifying or detecting *** the field of visual tracking,deep network has not been applied *** of the reasons is that its time consuming made the strong method could not meet the speed need of visual tracking.A novel simple tracker is proposed to complete tracking task.A simple six-layer feed-forward backpropagation neural network is applied to capture object ***,this representation is not robust enough when illumination changes or drastic scale changes in dynamic *** improve the performance and not to increase much time spent,image perceptual hashing method is employed,which extracts low frequency information of object as its fingerprint to recognize the object from its structure.64-bit characters are calculated by it,and they are utilized to be the bias terms of the neutral *** leads more significant improvement for performance of extracting sufficient object *** we take particle filter to complete the tracking process with the proposed *** experimental results demonstrate that the proposed algorithm is efficient and robust compared with the state-of-the-art tracking methods.

关键词： Visual tracking Image perceptual hashing Deep learning Neural network

Topology optimization of piezocomposite resonator for maximizing excitation strength and synthesizing desired eigenmodes

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Acta Mechanica Solida Sinica 2017年第5期30卷 531-539页

作者： Xuansheng Wang Zheqi lin Yiru ren School of Software Engineering Shenzhen Institute of Information Technology Shenzhen 518172 China Shenzhen Research Institute of Sun Yat-sen University Shenzhen 518057 China College of Mechanical and Vehicle Engineering Hunan University Changsha 410082 China

A topology optimization method is proposed for the design of piezocomposite resonator with the aim of maximizing excitation strength and synthesizing desired eigenmodes. The objective function consists of maximizing the electromechanical coupling strength at the mode of interest. The topology layout of a structure with desired eigenmodes is obtained by adding the modal assurance criterion as additional constraint in the topology optimiza- tion model. Numerical examples are presented and the results illustrate that aside from maximizing the electromechanical coupling strength, the existing eigenmode of the piezo- composite resonator can be modified to be the desired one at the mode of interest.

关键词： Topology optimizationPiezocomposite resonatorFinite element methodElectromechanical couplingcoefficientModal assurance criterion

Ion-Beam Bombarding Effects on Deposition of Carbon Nitride Films by Laser Ablation

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Chinese Physics Letters 1996年第11期13卷 878-880页

作者： YING Zhi-feng ren Zhong-min DU Yuan-cheng LI Fu-ming lin Jing ren Yun-zhu ZONG Xiang-fu Department of Physics and State Key Lab oratory for Materials Modification by LaserIon and Electron beamsFudan UniversityShanghai 200433 Institute of Materials Science Fudan UniversityShanghai 200433

In order to obtain high quality carbon nitride films,x-ray photoelectron spectroscopy and Raman spectrum were used to analyze several kinds of film:(a)laser-ablated amorphous carbon(a-C)films,(b)a-C films after a 1 keV nitrbgen ion beam bombardment.(c)carbon nitride(CN_(x))films synthesized by ablation assisted with ion beam bombardment,(d)CN_(x) films after a 50eV nitrogen ion beam bombardment,and(e)CN_(x) films after a 1 keV nitrogen ion beam *** comparison among these films showed that the concurrent deposition of CN_(x) films by ablation and a nitrogen ion beam should be better than the post-treatment of a-C films by nitrogen ion beam *** the case of concurrent deposited CN_(x) films,a post-treatment by a nitrogen ion beam bombardment with an appropriate energy(possibly less than 1 keV)was proposed to improve the ratio of C-N binding structures in the deposited films.

关键词： beam films amorphous

Plasticity and microstructure evolution of W-CeO2 rods with different short-duration pulse currents

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Rare Metals 2017年第12期36卷 981-986页

作者： Wen-Guang zhu Jian-Can Yang Jie Cao lin Huang Yu-Chen Xi Zuo-ren Nie School of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

To improve the formability of W-rare earth electrode, the influence of high-energy pulse on the plasticity property of W-CeOrods was investigated. The effects of current density(J), pulse width(tw), frequency(f), and strain rate on the plasticity of W-CeOrods were discussed in detail. Results of tensile tests show that the W-CeOrods applied with the electrical pulses obtain a maximum percentage total elongation at fracture(9.65 %), increased by118.7 % compared to that without pulses. This is owing to both the heat effect and the interaction of current between dislocations and rare earth additions. Electron back scattered diffraction(EBSD)-generated grain boundary(GB) maps suggest that the length of low-angle grain boundaries composed of high-density dislocations decreases after deformation while applying the pulse current. This demonstrates that the short-duration pulsed current enhances the mobility of dislocations. Scanning electron microscopy(SEM) images of the rods after deformation with the pulse current show that the long fiber-shaped additions become discontinuous,which could reduce the stress concentration and hinder the crack propagation.

关键词： Pulse current Plasticity W-CeO_2 rod Lowangle grain boundary

Analysis on Initial Defects Based on Mechanical State of Meniscus Shell

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Journal of Iron and Steel Research International 2015年第12期22卷 1085-1090页

作者： Xiang-ning MENG ren-gan lin Jie YANG Xiao-jing ZUO Miao-yong zhu School of Materials and Metallurgy Northeastern University

The meniscus shell plays an important role in slab quality and process operation for continuously cast steel. One decisive reason is initial solidifying shell and growing dendrite under the mechanical stress caused by mold oscil- lation and liquid steel flow to generate disturbance of casting. The mechanical state of meniscus shell was analyzed using mathematical models in combination with thermo-physical properties and flow rate of steel to shed light on the formation of initial defects. The results show that the mold oscillation is a critical factor on the initial crack formation because the periodic stress makes the shell bending. The formed crack may also expand and propagate due to the fol- lowing secondary cooling and straightening behavior. The primary dendrite has high possibility to be broken by fluid flow in the solidification front to lead to the non-uniform thickness of solidifying shell. The inter-dendrite bridging is also likely to be formed to produce other internal defects, such as air hole and solute enrichment in the residual mol- ten steel located in the bridging area.

关键词： continuous casting mold oscillationl meniscus shell initial defect mathematical model

New Perspective to Isogeometric Analysis:Solving Isogeometric Analysis Problem by Fitting Load Function

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2957-2984页

作者： Jingwen ren Hongwei lin School of Mathematical Sciences Zhejiang UniversityHangzhou310058China State Key Lab.of CAD&CG Zhejiang UniversityHangzhou310058China

Isogeometric analysis(IGA)is introduced to establish the direct link between computer-aided design and *** is commonly implemented by Galerkin formulations(isogeometric Galerkin,IGA-G)through the use of nonuniform rational B-splines(NURBS)basis functions for geometric design and *** promising approach,isogeometric collocation(IGA-C),working directly with the strong form of the partial differential equation(PDE)over the physical domain defined by NURBS geometry,calculates the derivatives of the numerical solution at the chosen collocation *** a typical IGA,the knot vector of the NURBS numerical solution is only determined by the physical domain.A new perspective on the IGAmethod is proposed in this study to improve the accuracy and convergence of the *** the PDE with IGA can be regarded as fitting the load function defined on the NURBS geometry(right-hand side)with derivatives of the NURBS numerical solution(left-hand side).Moreover,the design of the knot vector has a close relationship to theNURBS functions to be fitted in the area of data fitting in geometric ***,the detected feature points of the load function are integrated into the initial knot vector of the physical domainto construct thenewknot vector of thenumerical ***,they are connected seamlessly with the IGA-C framework for its great potential combining the accuracy and smoothness merits with the computational efficiency,which we call isogeometric collocation by fitting load function(IGACL).In numerical experiments,we implement our method to solve 1D,2D,and 3D PDEs and demonstrate the improvement in accuracy by comparing it with the standard IGA-C *** also verify the superiority in the accuracy of our knot selection scheme when employed in the IGA-G method,which we call isogeometric Galerkin by fitting load function(IGA-GL).

关键词： Isogeometric analysis collocation methods feature point detection knot vector

Rural Tourism Development in China:Principles,Models and the Future

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Journal of Mountain Science 2013年第1期10卷 116-129页

作者： WANG ling-en CHENG Sheng-kui ZHONG lin-sheng MU Song-lin DHRUBA Bijaya GC ren Guo-zhu Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Rural tourism in China,has undergone a rapid development in the last three *** is an emerging and effective catalyst that promotes industrial restructuring,agricultural development and the upgrading of rural ***,there remains little understanding about the core issues of rural tourism in China:the exact connotation,the principles,the development models and the future *** review paper identifies the key issues based on literature analysis,national statistics and press reports to form a general picture of the past,the current and the future prospects of China's rural *** paper firstly addresses the definition,content and principles of rural tourism,and then provides an overview and brief evaluation of the progress and the current development models in ***,based on the analysis of the experiences and problems,the authors sum up with five pathways of the future development of China's rural tourism from the perspective of rural tourism resources,product,market and promotion.

关键词： Rural tourism Definitions Principles Development models China

原发性骨质疏松潜在生物标志物的生物信息学分析

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中国组织工程研究 2025年第8期29卷 1741-1750页

作者：赵嘉诚任诗齐祝秦刘佳佳朱翔杨洋南通大学附属医院创伤中心江苏省南通市226001 南通大学医学院江苏省南通市226001 南通大学附属医院手外中心江苏省南通市226001

背景:原发性骨质疏松症的发病率高,但发病机制尚不完全清楚,目前尚缺乏有效的早期筛查指标和治疗方案。目的:通过综合生物信息学分析,进一步探索原发性骨质疏松症的发生机制。方法:原发性骨质疏松症数据来自公共基因表达数据库,筛选差... 详细信息

背景:原发性骨质疏松症的发病率高,但发病机制尚不完全清楚,目前尚缺乏有效的早期筛查指标和治疗方案。目的:通过综合生物信息学分析,进一步探索原发性骨质疏松症的发生机制。方法:原发性骨质疏松症数据来自公共基因表达数据库,筛选差异基因分别进行GO功能和KEGG通路富集分析。此外,将差异基因进行蛋白质-蛋白质相互作用网络确定原发性骨质疏松症相关核心基因,并通过最小绝对收缩和选择运算算法来识别并验证原发性骨质疏松症相关的生物标志物,并分别进行免疫细胞相关分析、基因富集分析以及药物标靶网络分析。最后将生物标志物行qPCR实验验证。结果与结论:①该研究中共获得126个差异基因以及前列腺素、表皮生长因子受体、丝裂原活化蛋白激酶3、转化生长因子B1和视网膜母细胞瘤基因1等5个生物标志物。②GO分析表明差异基因主要富集在细胞对氧化应激的反应以及自噬的调节等方面;KEGG分析显示主要集中在自噬以及细胞衰老等通路当中。③生物标志物的免疫分析发现,前列腺素,视网膜母细胞瘤基因1、丝裂原活化蛋白激酶3与免疫细胞密切相关。④基因富集分析表明,生物标志物与免疫相关途径有关。⑤药物标靶网络分析显示5个生物标志物与原发性骨质疏松症药物相关。⑥qPCR结果表明,前列腺素、表皮生长因子受体、丝裂原活化蛋白激酶3和转化生长因子B1在原发性骨质疏松症样本中,与对照样本相比表达显著上升(P<0.001),而视网膜母细胞瘤基因1在原发性骨质疏松症样本中,与对照样本相比表达显著下降(P<0.001)。⑦总之,该研究筛选并验证了5个原发性骨质疏松潜在生物标志物,为进一步深入探究原发性骨质疏松症的发病机制、早期筛查诊断及靶向治疗提供了参考依据。

关键词：原发性骨质疏松生物标志物生物信息学药物标靶网络蛋白质-蛋白质相互作用网络