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Science China(Life Sciences) 2004年第3期47卷 279-286页

作者： zHANG Wei FENG Jiannan shen Beifen Beijing Basic Medical Institute Beijing 100850 China Beijing Basic Medical Institute Beijing 100850 China Beijing Basic Medical Institute Beijing 100850 China

The genes of the heavy and light chain variable region (VH, VL) of z12 antibody against hTNF-a were cloned, and according to the translated sequence of amino acids, the spa-tial structures of VH and VL domains were modeled by using homology-based modeling method, followed by constructing the whole three-dimensional structure of Fv fragment. The complex model of Fv interacting with hTNF-a was gained with computer-guided molecular docking method, based on which, it was predicted that the epitope recognized by z12 was from 141 to 146 of hTNF-a. hTNF-a molecule was divided into two fragments of N-terminal region from 1 to 91 and C-terminal region from 92 to 157 with prokaryotic expression. The measured results suggested that the antigenic epitope recognized by z12 antibody was located in the C-terminal region 92-157 of hTNF-a, proving the predicted result reliable preliminarily. Further experimental results showed that after hTNF- 141-146 residues were deleted, z12 antibody almost lost the ability to recognize the mutant, suggesting that the amino acid residues from 141 to 146 of hTNF-a were specially recognized by z12 antibody.

关键词： human tumor necrosis factor-α, Fv, antigenic epitope, homology-based modeling, deletion.

The seamless model for three-dimensional datum transformation

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Science China Earth Sciences 2012年第12期55卷 2099-2108页

作者： LI BoFeng shen Yunzhong LI WeiXiao GNSS Research Centre Department of Spatial SciencesCurtin University of TechnologyGPO Box U1987PerthWA 6845Australia Department of Surveying and Geo-informatics Engineering Tongji UniversityShanghai 200092China Centre for Spatial Information Science and Sustainable Development Tongji UniversityShanghai 200092China

With extensive applications of space geodesy, three-dimensional datum transformation model has been necessarily used to transform the coordinates in the different coordinate *** essence is to predict the coordinates of non-common points in the second coordinate system based on their coordinates in the first coordinate system and the coordinates of common points in two coordinate ***, the computation of seven transformation parameters and the transformation of noncommon points are individually implemented, in which the errors of coordinates are taken into account only in the second system although the coordinates in both two systems are inevitably contaminated by the random ***, the coordinate errors of non-common points are disregarded when they are transformed using the solved transformation *** we propose the seamless (rigorous) datum transformation model to compute the transformation parameters and transform the non-common points integratively, considering the errors of all coordinates in both coordinate *** a result, a nonlinear coordinate transformation model is *** on the Gauss-Newton algorithm and the numerical characteristics of transformation parameters, two linear versions of the established nonlinear model are individually *** the least-squares collocation (prediction) method is employed to trivially solve these linear ***, the simulation experiment is carried out to demonstrate the performance and benefits of the presented *** results show that the presented method can significantly improve the precision of the coordinate transformation, especially when the non-common points are strongly correlated with the common points used to compute the transformation parameters.

关键词： coordinate transformation collocation total least squares Bursa model Gauss-Newton method

Finite Groups with Some Pronormal Subgroups

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Acta Mathematica Sinica,English Series 2011年第4期27卷 715-724页

作者： zhen Cai shen Wu Jie SHI School of Mathematical Sciences Suzhou University Suzhou 215006 P. R. China School of Mathematics and Statistics Chongqing University of Arts and Sciences Chongqing 402160 P. R. China

A subgroup H of finite group G is called pronormal in G if for every element x of G, H is conjugate to Hx in （H, Hx）. A finite group G is called PRN-group if every cyclic subgroup of G of prime order or order 4 is pronormal in G. In this paper, we find all PRN-groups and classify minimal non-PRN-groups （non-PRN-group all of whose proper subgroups are PRN-groups）. At the end of the paper, we also classify the finite group G, all of whose second maximal subgroups are PRN-groups.

关键词： Pronormal subgroups PRN-groups minimal non-PRN-groups PN-groups minimalsubgroups p-nilpotent groups

Aerodynamic airfoil design using the Euler equations based on the dynamic evolution method and the control theory

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Science China(Physics,Mechanics & Astronomy) 2011年第4期54卷 697-702页

作者： GAO YingYing HE Feng shen MengYu School of Aerospace Tsinghua University Beijing 100084 China

Based on the idea of adjoint method and the dynamic evolution method,a new optimum aerodynamic design technique is presented in this *** can be applied to the optimum problems with a large number of design variables and is time *** key of the new method lies in that the optimization process is regarded as an unsteady evolution,i.e.,the optimization is executed,simultaneously with solving the unsteady flow governing equations and adjoint *** examples for both the inverse problem and drag minimization using Euler equations have been presented,and the results show that the method presented in this paper is more efficient than the optimum methods based on the steady flow solution and the steady solution of adjoint equations.

关键词： Euler equations aerodynamic optimization dynamic evolution adjoint method

Influences of air CO2 on hydrochemistry of drip water and implications for paleoclimate study in a stream-developed cave, SW China

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Acta Geochimica 2016年第2期35卷 172-183页

作者： Xiaoxiao Wang Yanhong Wu Licheng shen Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049China School of Geographical Sciences Southwest UniversityChongqing 400715 China

Cave air CO_2 is a vital part of the cave environment. Most studies about cave air CO_2 variations are performed in caves with no streams; there are few studies to date regarding the relationship of cave air CO_2 variations and drip water hydrochemistry in underground stream–developed caves. To study the relationship of underground stream, drip water, and cave air CO_2, monthly and daily monitoring of air CO_2 and of underground stream and drip water was performed in Xueyu Cave from 2012 to *** results revealed that there was marked seasonal variation of air CO_2 and stream hydrochemistry in the cave. Daily variations of cave air CO_2, and of stream and drip water hydrochemistry, were notable during continuous monitoring.A dilution effect was observed by analyzing hydrochemical variations in underground stream and drip water after rainfall. High cave air CO_2 along with low p H and low δ^(13)C DIC in stream and drip water indicated that air CO_2 was one of the dominant factors controlling stream and drip water hydrochemistry on a daily scale. On a seasonal scale, stream flows may promote increased cave air CO_2 in summer; in turn, the higher cave air CO_2 could inhibit degassing of drip water and make calcite δ^(13)C more negative. Variation of calcite δ^(13)C(precipitated from drip water) was in reverse of monthly temperature, soil CO_2, and cave air CO_2. Therefore,calcite δ^(13)C in Xueyu Cave could be used to determine monthly changes outside the cave. However, considering the different precipitation rate of sediment in different seasons,it was difficult to use stalagmites to reconstruct environmental change on a seasonal scale.

关键词： Carbon dioxide - Underground stream Dripwater Paleoclimate reconstruction Xueyu Cave

A further understanding of the cation exchange mechanism for the extraction of Sr^(2+) and Cs^+ by ionic liquid

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Science China Chemistry 2013年第6期56卷 782-788页

作者： SUN TaoXiang shen XingHai CHEN QingDe Beijing National Laboratory for Molecular Sciences (BNLMS) Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental ScienceCollege of Chemistry and Molecular EngineeringPeking University

The cation exchange mechanism was further investigated during the extraction of Sr 2+ and Cs+ using the extractant dicyclo- hexano-18-crown-6 (DCH18C6) in an ionic liquid (IL)1-ethyl-3-methyimidazolium bis[(trifluoromethyl)sulfonyl]imide (C2 mimNTf2 ). The concentrations of both the cation C2 mim + and the anion NTf2 in aqueous phase were detected. The con-centration of NTf2 in the aqueous phase decreased as Sr2+ or Cs+ exchanged into the IL phase. Addition of C2 mim + or NTf2 as well as the variation of the solubility of C2 mimNTf2 influenced the extraction efficiency of Sr2+ or Cs+ .

关键词： ionic liquids extraction cation exchange Sr2+ Cs+

Highly Stereoselective and One-Pot Synthesis of Tetra-substituted Monofluoroalkenes with Aldehydes and Fluorobis（phenylsulfonyl）methane

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Chinese Journal of Chemistry 2013年第7期31卷 878-884页

作者： Xiao shen Chuanfa Ni Jinbo Hu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A highly stereoselective synthesis of tetrasubstituted monofluoroalkenes with aldehydes and fluorobis（phenyl- sulfonyl）methane （FBSM） in one pot has been developed. The reaction was amenable topara- and meta-substituted aryl aldehydes, 2-naphthaldehyde, and cinnamaldehyde, giving phenylsulfonyl-substituted monofluoroalkenes in 40%--86% yields with 98/2- 99/1 z/E ratios. The presence of the sulfonyl group enables the further transformation of the products into more useful monofluoroalkenes.

关键词： olefination aldehydes nucleophilic addition sulfones fluorine

Recent advances in membrane bioreactor technology for wastewater treatment in China

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Frontiers of Environmental Science & Engineering 2010年第3期4卷 245-271页

作者： Xia HUANG Kang XIAO Yuexiao shen State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Since the introduction of the membrane bioreactor(MBR)in China in the early 1990s,remarkable progress has been achieved on the research and application of this *** has now become one of the most active fields in the world in this *** review outlines the development of MBR-based processes in China and their performance of treating municipal and industrial *** membrane fouling is a critical operational problem with MBR processes,this paper also proposes updated understanding of fouling mechanisms and strategies of fouling control,which are mainly compiled from publications of Chinese *** for the commercial application of MBR in the country,the latest statistics of large-scale MBR plants(>10000 m^(3)·d^(–1))are provided,and the growth trend of total treatment capacity as well as its driving force is analyzed.

关键词： membrane bioreactor(MBR) municipal wastewater treatment industrial wastewater treatment membrane fouling commercial application China

Stereoselective formation of z-monofluoroalkenes by nickel-catalyzed defluorinative coupling of gem‑difluoroalkenes with lithium organoborates

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Chinese Chemical Letters 2022年第9期33卷 4277-4280页

作者： Yisa Xiao Weichen Huang Qilong shen Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

A method for stereoselective construction of z-monofluoroalkenes by nickel-catalyzed defluorinative coupling of gem‑difluoroalkenes in mild conditions was *** combination of lithium organoborate and znBr_(2) generated in situ lithium aryl zincates,which facilitates the transmetalation step of the nickel-catalyzed cross coupling reaction.

关键词： gem‑Difluoroalkenes Lithium organoborate Defluorination Nickel Coupling

基于三矩形谐振腔非通MIM波导的四重法诺传感

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原子与分子物理学报 2025年第3期42卷 116-123页

作者：王叶壮沈宏君陈俊坤王雅雯宁夏大学物理学院银川750000

为了得到高灵敏度的生物传感器,设计了一种可以激发出四重法诺共振的非通金属-绝缘体-金属(Metal-Insulator-Metal,MIM)波导传感器.采用了上下对称结构,由一个竖放矩形谐振腔和两个横放矩形谐振腔与总线波导共同作用而得到了四重法诺共... 详细信息

为了得到高灵敏度的生物传感器,设计了一种可以激发出四重法诺共振的非通金属-绝缘体-金属(Metal-Insulator-Metal,MIM)波导传感器.采用了上下对称结构,由一个竖放矩形谐振腔和两个横放矩形谐振腔与总线波导共同作用而得到了四重法诺共振.采用了有限时域差分方法计算了此结构的传输特性与z方向的归一化磁场,并详细分析了其法诺共振的产生机理.通过计算结构几何参数调节后的透射光谱,从而得出了四处法诺共振峰透射率和共振位置可以通过改变结构几何参数而获得独立调节.此外还发现在结构中添加不同浓度的葡萄糖溶液可以实现高折射率传感灵敏度(S),获得最高灵敏度2736.98nm/RIU,可以看出此结构对于折射率变化有很高的灵敏度,这为设计和优化纳米级别的折射率传感器提供了新的思路,还可以应用于电路构建前进行性能测试.

关键词：金属-绝缘体-金属传感器谐振腔法诺共振灵敏度

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