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LINEAR FINITE ELEMENT APPROXIMATIONS FOR THE TIMOSHENKO BEAM AND THE SHALLOW ARCH PROBLEMS

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Journal of Computational Mathematics 2002年第1期20卷 15-22页

作者： xiao-liang cheng Wei-min Xue Department of Mathematics Zhejiang UniversityXixi CampusHangzhou 310028China Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong

Focuses on a study that discusses the linear finite element approximations for the Timoshenko beam and the shallow arch problems with shear dampening and reduced integration. Information on the Timoshenko beam; Detail... 详细信息

关键词： Timoshenko beam shallow arch shear dampening reduced integration

A Monotonic Algorithm for Eigenvalue Optimization in Shape Design Problems of Multi-Density Inhomogeneous Materials

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Communications in Computational Physics 2010年第8期8卷 565-584页

作者： Zheng-fang Zhang Ke-wei liang xiao-liang cheng Department of Mathematics Zhejiang UniversityHangzhou 310027China

Many problems in engineering shape design involve eigenvalue *** relevant difficulty is that the eigenvalues are not continuously differentiable with respect to the *** this paper,we are interested in the case of multi-density inhomogeneous materials which minimizes the least *** the finite element discretization,we propose a monotonically decreasing algorithm to solve the minimization *** numerical examples are provided to illustrate the efficiency of the present algorithm as well as to demonstrate its availability for the case of more than two *** the computations are sensitive to the choice of the discretization mesh sizes,we adopt the refined mesh strategy,whose mesh grids are 25-times of the amount used in[*** and ***,***.,171(2001),pp.272-288].We also show the significant reduction in computational cost with the fast convergence of this algorithm.

关键词： Multi-density inhomogeneous materials the least eigenvalue optimization problem finite element method monotonic algorithm

Microstructure and Properties of Hot Rolled Ti-23Al-17Nb Alloy Sheets

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Journal of Iron and Steel Research International 2010年第9期17卷 64-68页

作者： ZHANG Jian-wei liang xiao-bo cheng Yun-jun LI Shi-qiong Central Iron and Steel Research Institute Beijing 100081 China

Microstructure and tensile properties of Ti-23Al-17Nb （at%） alloy sheets rolled in （a2 ＋ B2 ＋ O） phase field with the various heat treatments were studied. Before rolling the microstructure of the billet is B2 phase particles embedded in O phase continuity matrix. The B2 phases are deformed more greatly than a2/O phases during the same rolling step. The （a2 ＋B2） two phase equiaxed microstrueture can be obtained by solution treatment in （a2 ＋ B2） phase field. The B2 phases become the continuous matrix by recrystallization and growing up of B2 and thus anisotropy caused by rolling can be decreased. The microstructure obtained by solution treatment has better tensile properties than the microstructure gained by subsequent aging treatment in （O＋ B2） phase field because the O phases precipitate as the block structure during aging and results in the B2 matrix continuity being broken down.

关键词： Ti-23Al-27Nb rolled sheet microstructure property

NUMERICAL ANALYSIS OF SIDE DISCHARGES INTO A CHANNEL FLOW USING AN RNG k^(-ε)MODEL

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Journal of Hydrodynamics 1999年第3期11卷 44-54页

作者： Wang xiao jian cheng liang Deparment of Civil Engineering, The University of Western Australia, Nedlands 6907, Western Australia Cui Li Department of Civil Engineering, Dalian University of Technology, Dalian 116024, P.R.China (Received Sep.

Side discharge into a channel flow is numerically simulated using an RNG based k ε turbulence model. It is shown that the results of the recirculation zone obtained using the RNG k ε model generally agree better with the experimental results compared with those by the standard k ε model. The reason for the improvement of the results obtained using the RNG k ε model over those by the standard k ε model on this flow is analyzed. The flow at small discharge ratios is thoroughly investigated and it is found that the velocity profile at the jet exit is extremely non uniform at small discharge ratios. It is also found that the degree of the non uniformity decreases as the discharge ratio increases, and is very slight for discharge ratios larger than 2.0. The effects of calculation domain, mesh size, wall functions, bed roughness and discharge ratios on the size of separation zone are also investigated in detail.

关键词： RNG kε model side discharge flow separation zone bed roughness

DETERMINATION OF SENSITIZATION IN AUSTENITIC STAINLESS STEEL

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Chinese Chemical Letters 1993年第11期4卷 993-994页

作者： Quan Sheng WU, Wei HE, Chang Yi LIU, xiao liang cheng, Shen Hao CHEN Department of Chemistry, Shandong University, Jinan, 250100

The electrochemical potentiokinetic reactivation technique(EPR) and the potentiostatic pulse technique(PPT) have been used to detect sensitization of austenitic stainless steel. Compared with EPR, PPT has some advantages such as it can be conducted at greater speed and with less destruction, etc. The sensitivity of PPT can be improved by altering t_1/t_2 in a certain range and it will favour the detection of the specimen with lower degree of sensitization.

关键词： EPR DOS DETERMINATION OF SENSITIZATION IN AUSTENITIC STAINLESS STEEL Chen than

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GPS在水利水电高等级施工控制网中的应用

人民长江 2005年第9期36卷 52-54页

作者：肖成良云南省水利水电勘测设计研究院勘察分院云南昆明650021

高桥电站引水隧洞长达10 km,在当时属于云南省最长的隧洞之一,为确保施工控制网的精度,采用了GPS对控制网进行加密复测,并在控制网的设计方面作了几项新的技术革新:①采用蒙特卡洛法对控制网进行优化设计;②采用具有强制归心盘的观测墩... 详细信息

高桥电站引水隧洞长达10 km,在当时属于云南省最长的隧洞之一,为确保施工控制网的精度,采用了GPS对控制网进行加密复测,并在控制网的设计方面作了几项新的技术革新:①采用蒙特卡洛法对控制网进行优化设计;②采用具有强制归心盘的观测墩;③采用瑞士莱卡公司生产的DI2002+T2000高精度的红外测距仪进行施测,通过平差计算精度评定结果完全满足《规范》要求。

关键词： GPS 水电工程高等级控制网

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水利测绘产品质量分析与检验方法研究

水利水电技术 2007年第12期38卷 43-46页

作者：肖成良白少云云南省水利水电勘测设计研究院云南昆明650021

分析了影响测绘产品质量的主要因素,提出了完善测绘市场、加强水电测绘产品的检查验收是保证产品质量的关键,同时提出了产品质量的等级划分和检验方法,并且说明了根据测量工作的不同要求对检验方法及检验深度合理定位的必要性。

关键词：测绘产品质量分析检验市场竞争资质管理水利水电工程

应用TCA2003全站仪对庙林电站工程控制网精度的误差分析

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水利水电技术 2007年第12期38卷 62-65页

作者：白少云肖成良云南省水利水电勘测设计研究院云南昆明650021

介绍了TCA2003全站仪的基本原理及构成,并结合云南庙林电站工程情况,分析了应用全站仪进行控制网观测的优势。剖析了全站仪在减少测量误差中具有较大的优势,特别在消除照准误差、大气折光误差方面对控制网精度的提高具有特别重要的意义... 详细信息

介绍了TCA2003全站仪的基本原理及构成,并结合云南庙林电站工程情况,分析了应用全站仪进行控制网观测的优势。剖析了全站仪在减少测量误差中具有较大的优势,特别在消除照准误差、大气折光误差方面对控制网精度的提高具有特别重要的意义。利用TCA2003全站仪对大中型水利水电工程施工控制网进行外业观测,具有速度快、精度高、获取数据准确可靠等优点,有广泛的应用前景。

关键词： TCA2003全站仪施工控制网大气折光

海南捕鸟蛛毒素-IV对大鼠背根神经节细胞钠通道的抑制影响(英文)

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生物化学与生物物理学报 2003年第1期35卷 82-85页

作者：肖玉成梁宋平湖南师范大学生命科学学院湖南师范大学生命科学学院长沙410081

海南捕鸟蛛毒素 IV(HNTX IV)是从中国捕鸟蛛Seleconosmiahainana粗毒中分离得到的一种肽类神经毒素 ,在成年大鼠背根神经节 (DRG)细胞上观察了该毒素对电压门控钠通道的影响。在全细胞膜片钳条件下 ,HNTX IV能明显抑制哺乳动物神经性河... 详细信息

海南捕鸟蛛毒素 IV(HNTX IV)是从中国捕鸟蛛Seleconosmiahainana粗毒中分离得到的一种肽类神经毒素 ,在成年大鼠背根神经节 (DRG)细胞上观察了该毒素对电压门控钠通道的影响。在全细胞膜片钳条件下 ,HNTX IV能明显抑制哺乳动物神经性河豚毒敏感型 (TTX S)钠电流 ,但不影响河豚毒不敏感型 (TTX R)钠电流。HNTX IV对DRG细胞TTX S钠电流的抑制作用具有浓度依从性 ,其有效半抑制浓度 (IC50 )为 44 .6nmol/L。该毒素不影响DRG钠电流的激活与失活时间特征 ,但能导致钠通道的半数稳态失活电压向超极化方向漂移约 10 .1mV。结果表明HNTX IV是一种新型的蜘蛛毒素 ,其影响电压门控钠通道的机制可能有别于那些结合于通道位点 3来延缓钠电流失活时间特征的蜘蛛毒素如δ 澳洲漏斗网蛛毒素、μ 美洲漏斗网蛛毒素I VI等。

关键词：蜘蛛毒素背根神经节钠电流全细胞膜片钳