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Quenching of zinc phthalocyanine excited states by viologen surfactant assemblies——The influence of microenvironment

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chinese Journal of Chemistry 1993年第2期11卷 120-125页

作者： LIU,Ji-Xiang ZHOU,Qing-Fu XU,Hui-Jun Institute of Photoyraphic Chemistry,chinese Academy of sciences,{2. 100101 Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101

A series of functional surfactants of N-alkyl-N'-butyl viologens has been synthesized. The quenching of excited singlet and triplet states of zinc phthalocyanine was studied in DMSO and in mixed micelles containing the functional surfactant as one and cationic cetyl trimethylam- monium bromide(CTAB),anionic sodium dodecylsulfate(SDS)and neutral TX-100 surfactant as the other *** quenching and laser photolysis studies indicate that the functional surfactants are solubilized at different sites in micelles,the process depends on chain length and exerts great influence on the quenching of zinc phthalocyanine excited states.

关键词： CTAB nm Quenching of zinc phthalocyanine excited states by viologen surfactant assemblies The influence of microenvironment

A New Idea of Sinian Doushantuo'an Metaphyte Fossils from Xiuning, Anhui Province

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 491-501,515-517页

作者： Tang Feng, National Geological Museum of china, Xisi, beijing 10003.Yin Chongyu and Gao LinzhiInstitute of Geology, {2. Academy of Geological {3., 2. Baiwanzhuang, beijing 10003. Fei Zhenbi National Geological Museum of china Xisi Beijing 100034 Institute of Geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Beijing 100037 [?]Tang Feng Born in 1965 graduated from the Department of Earth sciences Nanjing University in 1987 got his master degree at the chinese Academy of Geological sciences in 1993. Now he is associate research professor of the National Geological Museum of{2. and engaged in the study of Precambrian stratigraphy and palaeontology.

This paper gives a summary of the fossil data from the Sinian Doushantuo' an Lantian Formation in the Xiuning area, Anhui Province, china, and reports the genital butt structure comparable to that of some modern advanced algae and the fossil structure comparable to the dehiscence of sporangia as well as the ontogenetic phenomenon occurring possibly from the formation of embryos by zygote germination to the production of sessile benthonic algal adults. This phenomenon furnishes a useful clue to the further study of the life history of alternate generations in advanced algae and provides megafossil evidence for the sex differentiation of metaphytic algae.

关键词： Doushantuo' an stage metaphyte fossil reproductive structure alternation of generations Xiuning Anhui

Analysis　of　Solidiflcation　in　the　Presence　of　High　Rayleigh　Number　Convection　in　an　Enclosure

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Journal of Thermal Science 1994年第3期3卷 173-176页

作者： Yuwen Zhang (School of Energy and Power Machinery Engineering, Xi’an Jiaotong University, Xi’an 710049, china)Yonglin Ju (chinese Academy of {2., {3., china)

A simple and convenient analysis of the process of time-dependent solidification in an enclosed liquid cooled from the side in the presence of natural convection is presented, the influence of each parameter on the process of solidification is carried out systematically. The accuracy of this model is justified by comparing its predicting values with the Previous results.

关键词： solidification high forleigh number analytic solution

Roles of the Nanog protein in murine F9 embryonal carcinoma cells and their endoderm-differentiated counterparts

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Cell Research 2006年第07期16卷 641-650页

作者： Yanmei Chen~1 Zhongwei Du~2.Zhen Yao~1 ~1Laboratory of Molecular and Cell Biology,Institute of Biochemistry and Cell Biology,Shanghai institutes for Biological sciences,chinese Academy of sciences,graduate School of the chinese Academy of sciences,3.0} Yueyang Road,Shanghai 2.003.,china ~2.epartment of Anatomy,School of Medicine,Waisman Centen Wicell Institute,University of Wisconsin,Madison,WI53.05,USA LaboratoryofMolecularandCellBiology InstituteofBiochemistryandCellBiologyShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesGraduateSchooloftheChineseAcademyofSciences320YueyangRoadShanghai200031

Nanog is a recently discovered homeodomain transcription factor that sustains the pluripotency of embryonic stem(ES)cells and blocks their differentiation into *** murine F9 embryonal carcinoma cell line is a well-docu-mented model system for endoderm cell lineage ***,we examined the function of Nanog in F9 cellendoderm ***-expression of Nanog returns the F9 cells to the early status of ES cells and represses thedifferentiation of primitive endoderm and parietal endoderm in F9 cells,whereas it has no effect on the differentiation ofvisceral *** contrast,the expression of C-terminal domain-truncated Nanog spontaneously promotes endodermdifferentiation in F9 *** data suggest that Nanog is required to sustain the proper undifferentiated status of F9cells,and the C-terminal domain of Nanog transduces the most effects in repressing primitive endoderm and parietalendoderm differentiation in F9 cells.

关键词： Nanog F9 embryonal carcinoma ceils endoderm differentiation

Tensor Theory of High Energy Electron Diffraction and Its Applications in Crystalography

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电子显微学报 1997年第4期 157-160页

作者： L. M.Peng (beijing Laboratory of Electron Microscopy, chinese Academy of {2., P.O. Box 2.2., beijing 100080, P.R. china)

ＴｅｎｓｏｒＴｈｅｏｒｙｏｆＨｉｇｈＥｎｅｒｇｙＥｌｅｃｔｒｏｎＤｉｆｆｒａｃｔｉｏｎａｎｄＩｔｓＡｐｐｌｉｃａｔｉｏｎｓｉｎＣｒｙｓｔａｌｏｇｒａｐｈｙＬ．Ｍ．Ｐｅｎｇ（ＢｅｉｊｉｎｇＬａｂｏｒａｔｏｒｙｏｆＥｌ... 详细信息

ＴｅｎｓｏｒＴｈｅｏｒｙｏｆＨｉｇｈＥｎｅｒｇｙＥｌｅｃｔｒｏｎＤｉｆｆｒａｃｔｉｏｎａｎｄＩｔｓＡｐｐｌｉｃａｔｉｏｎｓｉｎＣｒｙｓｔａｌｏｇｒａｐｈｙＬ．Ｍ．Ｐｅｎｇ（ＢｅｉｊｉｎｇＬａｂｏｒａｔｏｒｙｏｆＥｌｅｃｔｒｏｎＭｉｃｒｏｓｃｏｐｙ，...

关键词： Its and Diffraction Crystalography Applications

Partial Synthesis of Macrolide Alkaloid Euonine

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chinese Chemical Letters 1998年第10期9卷 927-928页

作者： Yuan Chao LI Shan Hao JIANG Xiao Yi WANG (Shanghai Institute of Materia Medica, chinese Academy of sciences, Shanghai, 2.003. Department of Environmental Chemistry and Engineering, {2. Polytechnic University,{2., 10002.) chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China beijing Polytech Univ Dept Environm Chem & Engn Beijing 100022 Peoples R China

The macrolide alkaloid euonine 1 with pharmacologic activity was prepared from the alkaloid wilforgine 2. Their structures were confirmed by IR, NMR, MS and optical rotation.

关键词： tripterygium macrolide alkaloid wilforgin euonine

额叶在启动效应中的作用机制:对额叶损伤病人颜色命名和词命名任务的分析

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心理学报 2003年第5期35卷 610-616页

作者：杨炯炯翁旭初管林初匡培梓张懋植孙伟建于生元北京大学心理学系北京100871 中国科学院心理研究所北京100101 首都医科大学附属北京天坛医院神经外科北京100050 中国人民解放军3.7医院神经外科北京100853 中国人民解放军总医院神经内科北京100853

以额叶损伤病人为被试 ,探讨在知觉型联想启动和知觉启动中 ,额叶的作用及其内在机制。实验任务包括颜色命名和词命名任务 ,以及相应的再认任务。结果表明 ,额叶损伤病人在颜色命名和词命名任务中 ,对旧词和重组颜色词的命名时间都没有... 详细信息

以额叶损伤病人为被试 ,探讨在知觉型联想启动和知觉启动中 ,额叶的作用及其内在机制。实验任务包括颜色命名和词命名任务 ,以及相应的再认任务。结果表明 ,额叶损伤病人在颜色命名和词命名任务中 ,对旧词和重组颜色词的命名时间都没有明显差别 ,联想启动和颜色启动效应受损 ,但轻度记忆损伤病人与正常对照组之间的再认成绩相似。相关分析发现联想启动和颜色启动与额叶的多项功能有中度相关。这表明 ,额叶参与了知觉型联想启动效应和知觉启动。

关键词：联想启动知觉启动额叶内隐记忆执行功能

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低渗透裂缝油藏渗吸法采油数值模拟理论研究

水动力学研究与进展（A辑） 2004年第4期19卷 440-445页

作者：殷代印蒲辉吴应湘大庆石油学院石油工程学院黑龙江大庆163318 中科院力学研究所北京100080

　根据低渗透裂缝油藏渗吸法采油渗流机理,建立了双孔双渗渗吸法采油数学模型,并给出了数值解法和流动系数的取值方法。通过实例验证,该方法计算的含水率指标与矿场实际值符合程度较高。在此基础上,定量分析了渗吸法采油的主要影响因素... 详细信息

　根据低渗透裂缝油藏渗吸法采油渗流机理,建立了双孔双渗渗吸法采油数学模型,并给出了数值解法和流动系数的取值方法。通过实例验证,该方法计算的含水率指标与矿场实际值符合程度较高。在此基础上,定量分析了渗吸法采油的主要影响因素,结论是:裂缝与基质渗透率比大于100,裂缝密度大于0.03.条/m,油水粘度比小于15,毛管力较大的水湿油藏适合渗吸法采油,能够提高水驱采收率1%以上。

关键词：渗吸法采油数值模拟毛管力流动系数采收率

THE　ISOLATION　AND　CHEMICAL　STRUCTURE　OF　ISOANNONARETICINS，A　PAIR　OF　2.EPIMERS　FROM　ANNONA　RETICULATA（ANNONACEAE）

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chinese Chemical Letters 1996年第1期7卷 19-22页

作者： Jing’Guang YU and Dong LIU(Institute of Medicinal Plant Development, chinese Academy of Medical sciences andPeking Union Medical College, {2. 100094) Inst. of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100094

A new acetogenin 2.4ets-cis-isoannonareticin (2.1) (2.4-cis-bullatacinone) and a known bullatacinone (2.4--trans-isoannonareticin) (2.2. were a pair of isomersepimeric at C-2.which were isolated as two pure natural compounds from Annonareticulata L. by using preparative TLC. Their structures and the relativestereochemistry were elucidated on the basis of the spectral analysis.

关键词： DENSICOMA ANNONACEAE ACETOGENINS POLYKETIDES BULLATA