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91.
Plasmapropertiesoflaser-ablatedSttargetinairWangXiang-Tai(王象泰);ManBao-Yuan(满宝元);WangGong-Tang(王公堂);FanXi-Jun(樊锡君);WangJun(王军)...  相似文献   
92.
TheCubooctahedronShape──ASuboptimalCellShapefor3-DimensionalCellularSystemChaGuangming;LiZhengmao;LuFan(UniversityofElectroni...  相似文献   
93.
Autoantibodies to the thyrotropin receptor (TSHR) can act as thyrotropin agonists or antagonists, or can cause thyroid hypertrophy. Neither the autoantibody-binding sites on the TSHR nor the intracellular mechanisms by which the autoantibodies mediate their diverse functional effects are completely understood. This article reviews how cloning of the TSHR has contributed to our understanding of its structure and function, and has allowed induction of experimental autoimmunity to the TSHR.  相似文献   
94.
OBJECTIVES: To examine stability of -glutamyltransferase (GGT) activity in stored serum from neonatal calves. ANIMALS: 10 commercial beef calves between 36 and 60 hours old. PROCEDURE: Serum samples were obtained from the calves, and each sample was divided into 8 aliquots. Serum GGT activity was measured on day 0 (fresh) and days 1, 2, 3, and 4 of refrigerated storage (4 C) and weeks 1, 2, and 3 of frozen storage (-20 C). RESULTS: Serum GGT activities for each of the refrigerated aliquots did not significantly differ from day zero, with serum GGT activity (expressed as a percentage of initial activity) > 99% on all 4 days. Serum GGT activity in frozen aliquots decreased significantly after 1 and 2 weeks of frozen storage, 97 and 98%, respectively; however, this decrease in GGT activity was not biologically significant. The observed GGT activity did not decrease significantly in the samples stored frozen for 3 weeks; these samples retained 99% of initial activity. CONCLUSION: The observed stability of serum GGT activity indicates that serum may be obtained, stored, and batch processed at a later time. This stability during storage is important to the success of a bovine passive transfer monitoring program based on GGT activity.  相似文献   
95.
本文根据光传输理论导出介导消光系数,折射率与介质电磁参数,光波频率,电偶极子浓度及迁移率等的关系,分析了光激发与增加气敏介质的氧吸附的规律,结合实验说明气敏薄膜的光学变化机制。  相似文献   
96.
在简要介绍CTS-26型超声探伤仪工作原理及组成的基础上。对其几种典型故障作了具体的分析和处理。  相似文献   
97.
The recrystallization behaviour of cold drawn MP159 alloy was investigated by optical and TEM examinations. It is found that the platelet ε phase in the MP alloy inhibits the recrystallization,and this effect makes the MP159 alloy with high recrystallization temperature of about 920℃.This inhibition mainly comes from the increasing of the interfacial energy, which results from the change of the coherent interfaces of (0001)hcp//(111)fcc into the incoherent interfaces when the recrystallizing grain fronts bypass the platelet ε martensite. The increasing of the interfacial energy also causes the dissolution of a few segments on the ε martensite platelets, which decreases the strength of the MP alloy  相似文献   
98.
A new time finite-element method based on the extrapolation technique and the Galerkin time finite-element method is presented. In this method, the second-order governing differential equations of motion for dynamic problems are rewritten as a set of first order differential equations in state space. The standard Galerkin method is then employed for the temporal discretization. The algorithm is first-order accurate only. Based on the first-order Galerkin time finite-element formulation, the extrapolation technique is introduced to improve the order of accuracy. It is achieved by expressing the numerical amplification matrix of higher-order algorithm as a linear combination of the basic amplification matrices evaluated at selected instances of time. The matrices are combined with different weighting factors. The pairs of the selected instance of time and the corresponding weighting factors are free parameters. Unconditionally stable higher-order accurate formulations can be derived by properly choosing the free parameters. Algorithms up to fourth-order accurate are presented in this paper. Detailed analyses on stability, numerical dissipation and numerical dispersion are also given. Comparisons of the present algorithms with some well-known time-integration methods are presented to demonstrate the versatility of the present method, in particular its accuracy in the higher-order formulations.  相似文献   
99.
范志康  梁淑花 《功能材料》1996,27(5):472-474
电流变流体是近年来逐渐受人们重视的一种功能材料,本文介绍其国内、外发展过程及研究现状。  相似文献   
100.
针对750m^3高炉铁水生产富余状况,制订了富余铁水向铸铁机铸铁的调送方案,通过创新思维、系统挖潜、优化资源配置等措施的实施,保证了750m^3高炉的正常生产,取得了良好效果。  相似文献   
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