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THE CRACK INITIATION APPROACH FOR DURABILITY ANALYSIS

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chinese Journal of Aeronautics 1993年第1期 32-36页

作者： Fei Bin-jun,Liu Wen-ting,Xiong Jun-jiang (beijing university of Aeronautics and Astronautics,beijing,china,100083)

A crack initial life analysis method for durability analysis is developed in this *** p—S-N curves of structure CIL is fitted with the shape parameters of material fatiguelife p-S-N curves. The probability of crack length exceeding the economic repair limitp(i,t) under load spectrum is established. The methods for estimation of damage degreeand economic life of structure are given. Finally, an example of point weld structure ispresented.

关键词： load CFA THE CRACK INITIATION APPROACH FOR DURABILITY ANALYSIS EIFS length CIL

Analysis of transition routine and packing structure of the confined long alkyl side groups:crossover of mesophase to crystalline structure

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Analysis of transition routine and packing structure of the ...

4th International Symposium on Engineering Plastics

作者： Haifeng Shi~(+ *) Xingxiang Zhang ~+ Yong Zhou ~(++) and Dujin Wang~(++) Institute of Macromolecular and Functional Fiber Tianjin Polytechnic university Tianjin 300160 china beijing National Laboratory for Molecular sciences CAS Key Laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry chinese academy of sciences beijing 100080 china

＜正＞Investigation of the transition routine and packing structure of the confined long alkyl side groups not only contributes the understanding of the microscale packing situation of side groups,but also provides one suitable way to probe the early stages of crystallization of *** our present experimental results on N-alkylated poly（p-benzamide）s（PBA（n）Cs）,polyethyleneimines（PEI（n）Cs）,and

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THE RATES OF CONVERGENCE OF M-ESTIMATORS FOR PARTLY LINEAR MODELS IN DEPENDENT CASES

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chinese Annals of Mathematics,Series B 1996年第3期17卷 317-324页

作者： LIU LUOFEI(Depatment of Mathematics, Jishou university, Hunan 416000, china) beijing UNIV DEPT PROBABIL & STATBEIJING 100871PEOPLES R CHINA UNIV SCI & TECHNOL china GRAD SCHBEIJING 100039PEOPLES R CHINA

The author proves several embedding theorems for finite covering maps, principal G-bundlesinto bundles. The main results are1. Let π: E→X be a finite covering mapt and X a connected locally pathconnectedparacompact space. If cat X≤5 k, then the finite covering space π: E→X can be embeddedinto the trivial real k-plane bundle.2. Let x: E→ X be a principal G-bundle over a paracompact space. If there exists alinear action of G on F (F = R or C) and cat X≤ k, then π: E→X can be embedded intofor any F-vector bundles ζi, i = 1,’’’ k.

关键词： Lusternik-Schnirelmann category Finite covering map Principal G-bundle

Pedogenesis affecting the Matuyama-Brunhes polarity transition recorded in chinese loess?

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Pedogenesis affecting the Matuyama-Brunhes polarity transiti...

中国科学院地质与地球物理研究所2001学术年会

作者： GUO Bin~1,ZHU Rixiang~1,Florindo Fabio~2, PAN Yongxin~1 & YUE Leping~3 1.Institute of Geology and Geophysics,chinese academy of sciences, beijing 100101,china 2.Istituto Nazionale di Geofisica,Rome,Italy 3.Department of Geology,Northwest university,Xi’an 710029,china

A detailed record of the Matuyama-Brimhes (M-B) transition has been obtained from the loess unit 8(L8) at Duanjiapo(34.2°N,109.2°E),Shannxi Province of china. An investigation of the rock magnetic properties using hysteresis loops,thermomagnetic analyses identifies pseudo-single domain magnetite as the main carrier of the remanence, with a small contribution from maghemite and hematite. The paleo-direction records obtained reveal:(i) The M-B transition was recorded in the middle and lower part of L8,and comprises of five fast reversals.(ii) The duration of the M-B polarity transition related to the directional change is about 4800 a.(iii) The virtual geomagnetic pole(VGP) path during the transition is confined over Africa,peaked 90°away from the sampling site,in contrast with the results obtained from the Weinan loess *** different VGPs are probably attributed to the pedogenesis.

关键词： M-B polarity transition VGP path pedogenesis loess

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二项分布基于logit变换的近似信仰推断

系统科学与数学 2009年第8期29卷 1071-1078页

作者：熊世峰牟唯嫣中国科学院数学与系统科学研究院北京100190 北京建筑工程学院理学院北京100044

利用调整的logit变换后估计量的渐近正态性对二项分布建立了近似的枢轴方程,并由此得到了二项分布参数的一种近似信仰分布.对一样本和两样本情形的数值结果表明,该近似信仰分布导出的区间估计具有比文献中推荐的区间估计更好的小样本频... 详细信息

利用调整的logit变换后估计量的渐近正态性对二项分布建立了近似的枢轴方程,并由此得到了二项分布参数的一种近似信仰分布.对一样本和两样本情形的数值结果表明,该近似信仰分布导出的区间估计具有比文献中推荐的区间估计更好的小样本频率性质.

关键词：二项分布信仰推断枢轴方程频率性质 logit变换.

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流式细胞术的最新进展

分析测试学报 2004年第6期23卷 124-128页

作者：杨蕊邹明强吉林大学化学学院微分析仪器研究所吉林省光谱分析仪器研究所吉林长春130023 中国检验检疫科学研究院北京100025

流式细胞术是一项集多种技术于一体的新型高科技细胞分析技术 ,是一种自动而迅速地进行细胞及免疫分析的标准方法。近年来在其基础上建立起来很多新型的流式细胞仪系统 ,具有体积小、功能全、价格低、使用方便、应用广泛等特点。

关键词：流式细胞术生物医学分析技术激光光源数据存储细胞分选免疫荧光测试技术

Effects of benactyzine on action potentials and contractile force of guinea pig papillary muscles

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郑州大学学报(医学版) 2000年第2期35卷 124-127页

作者： DING Zhongren 1)△ , ZHANG Yan 2) , ZHANG Guiqing 2) , KE Jun 2) , HU Xiangjie 2) 1)Department of Hematology,Peking Union Medical Hospital,chinese academy of Medical sciences,beijing 100730 2)Department of Pharmacology, Henan Medica Department of Hematology Peking Union Medical HospitalChinese Academy of Medical SciencesBeijing 100730 Department of Pharmacology Henan Medical UniversityZhengzhou 450052

Aim: To explore the effects of benactyzine (BEN) on the action potential and contractile force in guinea pig papillary muscles. Methods: Conventional microelectrode technique was used to record the fast action potentials (FAP) and slow action potentials (SAP) of guinea pig papillary muscles. Results: Benactyzine 5, 10, 50 μmol·L -1 suppressed the maximal upstroke velocity ( v max ) of FAP and contractile force (Fc) concentration dependently while prolonged the action potential duration at 50%, 90% repolarization (APD 50 , APD 90 ) and effective refractory period (ERP) of FAP. The suppression on the v max was frequency dependent. Benactyzine 5, 10,50 μmol·L -1 lengthened the APD50, APD90 of SAP induced by isoprenaline or histamine when perfused with KCl 22 mmol·L -1 Tyrode’s solution. The v max of the SAP was not decreased by benactyzine 5, 10 μmol·L -1 but by 50 μmol·L -1 . The effects on the SAP were antagonized by elevation of the extracellular calcium from 2.0 to 5.6 mmol·L -1 . The effects of benactyzine on SAP elicited by tetrodotoxin resembled that by isoprenaline or histamine except the more pronounced suppression on v max and action potential amplitude (APA). The persistent rapid spontaneous activity and triggered tachyarrhythmia induced by ouabain were also abolished immediately by benactyzine 5 μmol·L -1 . Conclusion: Benactyzine can inhibit Na +, K +, Ca 2+ transmembrane movement and intracellular Ca 2+ mobilization in the myocardium, and this may be the electrophysiological basis of its effects against experimental arrhythmias.

关键词： benactyzine papillary muscle action potential myocardial contraction tetrodotoxin

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催化剂颗粒流的基本方程及其应用(Ⅰ)

化工冶金 1989年第2期10卷 24-31页

作者：周世辉石油大学北京研究生部

本文借助于土力学和流体力学等的基本方法,对催化剂颗粒流作了五点假设,建立了封闭的动力学基本方程.为求解移动床和管道内催化剂的高密度重力流、固定床和高密度输送流等奠定了基础。

关键词：催化剂颗粒流基本方程

Femtosecond time-resolved measurements of Quarterthiophene:fast singlet-triplet intersystem crossing

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Femtosecond time-resolved measurements of Quarterthiophene:f...

第十六届全国原子与分子物理学术会议

作者： Simei Sun,Song Zhang and Bing Zhang State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,chinese academy,Wuhan 430071,PR china graduate School of the chinese academy of Science,beijing 10049,PR china

Thiophene-based oligomers have been extensively studied theoretically and experimentally,both for applications such as light-emitting diodes or field-effect transistors,and for a better understanding of physical prope...

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