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611.
After Wenchuan Ms8.0 earthquake, the surface fractures have been investigated in Beichuan City and Yingxiu Town. It was found that the Beichuan-Yingxiu earthquake fracture zone trends northeastward, dipping to northwest. The earthquake fracture zone is mainly characterized by thrust faulting with small amounts of strike-slip movement, and demonstrating various complexities for different areas. The phenomena related to dextral strike-slip displacement are found in Beichuan City and those related to left-lateral strike-slip movement in Yingxiu Town. The compressive shortening of the two surface fracture zones in Beichuan City is 2.8-3.9 m and the left-lateral strike-slip displacement of the surface fractures in Yingxiu Town is 0.52 m. 相似文献
612.
A carbon paste electrode modified with multi-walled carbon nanotubes (MWCNT) was prepared and the determination of ultra trace amount of zirconium based on the anodic adsorptive voltammetry of the zirconium-calcium-alizarin red S mix-polynuclear complex is described in this paper for the first time. The results showed that the sensitivity and the selectivity of the method are excellent. The second derivative linear scan voltammograms of the complex were recorded by polarographic analyzer from 200 to 1200 mV (vs. SCE) and it was found that the complex can be adsorbed on the surface of the electrode, yielding a peak at about 840 mV, corresponding to the oxidation of ARS in the complex. The peak current increases linearly with Zr (IV) concentration in the range of 6.0×10^-12--6.0×10^-11 mol. L^-1 (accumulation time 120 s), 6.0×10^-11--2.0×10^-9 mol. L-1 (accumulation time 90 s) and 2.0×10^-9--1.0×10^-7 mol. L^-1 (accumulation time 60 s) and the detection limit (S/N = 3) is 2.0×10^-12 mol. L^-1 (accumulation time 180 s). The procedure has been successfully applied to the determination of zirconium in the ore samples. 相似文献
613.
YunHui Hu XiaoHua Deng Meng Zhou RongXin Tang Hui Zhao Song Fu ZhiWen Su JingFang Wang ZhiGang Yuan R. Nakamura W. Baumjohann H. R. Eme C. M. Carr 《科学通报(英文版)》2008,53(12):1880-1886
Magnetic reconnection is a very important and fundamental plasma process in transferring energy from magnetic field into plasma. Previous theory, numerical simulations and observations mostly concentrate on 2-dimensional (2D) model; however, magnetic reconnection is a 3-dimensional (3D) nonlinear process in nature. The properties of reconnection in 3D and its associated singular structure have not been resolved completely. Here we investigate the structures and charactedstics of null points inside the reconnection diffusion region by introducing the discretized Poincar6 index through Gauss integral and using magnetic field data with high resolution from the four satellites of Cluster mission. We estimate the velocity and trajectory of null points by calculating its position in different times, and compare and discuss the observations with different reconnection models with null points based on characteristics of electric current around null points. 相似文献
614.
Zhang Yong Liu ZhaoHui Liu Cheng Yang ZuJun Deng KeJun Peng JinHua Zhou JianPing Li GuangRong Tang ZongXiang Ren ZhengLong 《科学通报(英文版)》2008,53(1):58-69
During the process of alien germplasm introduced into wheat genome by chromosome engineering, extensive genetic variations of genome structure and gene expression in recipient could be induced. In this study, we performed GISH (genome in situ hybridization) and AFLP (amplified fragment length polymorphism) on wheat-rye chromosome translocation lines and their parents to detect the identity in genomic structure of different translocation lines. The results showed that the genome primary structure variations were not obviously detected in different translocation lines except the same 1RS chromosome translocation. Methylation sensitive amplification polymorphism (MSAP) analyses on genomic DNA showed that the ratios of fully-methylated sites were significantly increased in translocation lines (CN12, 20.15%; CN17, 20.91%; CN18, 22.42%), but the ratios of hemimethylated sites were significantly lowered (CN12, 21.41%; CN17, 23.43%; CN18, 22.42%), whereas 16.37% were fully-methylated and 25.44% were hemimethylated in case of their wheat parent. Twenty-nine classes of methylation patterns were identified in a comparative assay of cytosine methylation patterns between wheat-rye translocation lines and their wheat parent, including 13 hypermethylation patterns (33.74%), 9 demethylation patterns (22.76%) and 7 uncertain patterns (4.07%). In further sequence analysis, the alterations of methylation pattern affected both repetitive DNA sequences, such as retrotransposons and tandem repetitive sequences, and low-copy DNA. 相似文献
615.
Semi-crosslinked polyacrylamides as high-resolution and dynamic self-coating sieving matrices for protein capillary electrophoresis 总被引:1,自引:0,他引:1
This paper describes non-gel capillary sieving electrophoresis employing semi-crosslinked polyacrylamide as a high performance and low viscous replaceable separation matrix for separation of non-denatured protein separation. Arising from the fine sieving and dynamic coating ability of this polymer, a mixture of basic proteins lysozyme, cytochrome C, ribonuclease A, and trypsin was resolved with excellent reproducibility. Mixing different semi-crosslinked polyacrylamides together further improves the separation. The separtion mechanism was analyzed. With network structure developed to an intermediate state between crosslinked gel and linear polymer solutions, these semi-crosslinked polyacrylamide polymers demonstrate a promise as a new class of size sieving separation medium, not only in capillary electrophoresis, but also in microfluidic chip separation schemes. 相似文献
616.
The mobilization of rat’s mesenchymal stem cells into peripheral blood by LiCL and its potency differentiation 总被引:2,自引:0,他引:2
DENG Jun ZOU ZhongMin ZHOU TaoLi AI GuoPing WANG JunPing DONG ShiWu SU YongPing↑ Institute of Combined Injury State Key Laboratory of Trauma Burns Combined Injury Department of Preventive Medicine Third Military Medical University Chongqing China Department of Pathogenic Biology Third Military Medical University Chongqing China 《科学通报(英文版)》2008,53(17):2632-2638
Mesenchymal stem cells (MSCs) are multipotent cells, which can differentiate into different tissues. It is still controversial whether MSCs can be isolated from adult peripheral blood (PB) under normal conditions and whether they can be mobilized in a way similar to that of hematopoieUc stem cells (HSCs). In this study, rat MSCs circulating in the PB under normal conditions can be isolated and cultured, and MSCs from PB and BM can be mobilized by LiCL. The mobilized MSCs can be induced to differentiate into neuron by such factors as β-mercaptoethanol and supernatants of nerve cell cultures. The present study provides a broader perspective on the repair of neural trauma. 相似文献
617.
邓新文 《杭州师范学院学报(社会科学版)》2008,30(6):37-41,62
马一浮的“六艺一心论”,是继郑玄的《六艺论》之后系统阐述六艺要旨的一部大论。摆在马一浮面前的有两大问题:一是学科纷呈,学派纷争,如何求其统合的问题;二是经学如何从近三百年的疑古一考古一复古一疑古的循环变奏和受西学冲击后的苦闷彷徨中寻找出路的问题。马一浮“六艺一心论”,可以说是解决上述两大问题的一次比较成功的尝试。“六艺一心论”是如何解决的呢?一是依其“同本异迹”的统类方法,将全部学术汇归于六艺;二是依其“心外无物”的本体论,将六艺摄归于一心。前者解决的是学科纷呈、学派纷争的问题,后者解决的是经学向何处去的问题。 相似文献
618.
凯瑟琳·安·波特小说中的“另类”人物 总被引:1,自引:0,他引:1
凯瑟琳.安.波特在小说中通常把人物置于一种人力无法控制的环境中来体现人物的生存困境。本文借用俄国形式主义文论的功能性人物与心理性人物两个概念来解读波特小说中的两类"另类"人物的生存困境。 相似文献
619.
团队多样性对知识共享的反向作用机制研究 总被引:2,自引:0,他引:2
多样化团队在组织变革和组织设计中日益受到重视,多样化团队对组织绩效有诸多的好处,但其带来的问题也不容忽视。问题表征差异和评价偏见使团队成员看待团队问题的视角各不相同,对同一信息的理解和评价结果产生差异,从而阻碍了团队的信息交流,可能导致功能失调的冲突。 相似文献
620.
描述了软件行业诚信系统的业务流程、主要功能、技术架构及在项目中的实现. 相似文献