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吉林陨石钻孔样品中宇宙线成因核素的深度分布与宇宙线照射历史

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中国科学(A辑数学物理学天文学技术科学) 1987年第1期 82-89页

作者：欧阳自远范彩云易惟熙王先彬 f.begemann T.Kirsten G.Heusser E.Pernicka 中国科学院地球化学研究所中国科学院兰州地质研究所 Max-Planck-Institut für Chemie Mainz Max-Planck-Institut fur Kernphysik Heidelberg Heidelberg 贵阳

成功地对吉林Ⅰ号陨石取得了平行与垂直第一阶段母体表面并相交于第二阶段母体中心的钻孔岩蕊.对两个钻孔的样品进行了系统的宇宙线成因核素(3He,20,21,22Ne,22Na,26Al,53Mn,60Co)、放射成因气体和俘捕稀有气体的研究,证实吉林陨石具有... 详细信息

成功地对吉林Ⅰ号陨石取得了平行与垂直第一阶段母体表面并相交于第二阶段母体中心的钻孔岩蕊.对两个钻孔的样品进行了系统的宇宙线成因核素(3He,20,21,22Ne,22Na,26Al,53Mn,60Co)、放射成因气体和俘捕稀有气体的研究,证实吉林陨石具有典型的两阶段宇宙线照射历史,确证作者曾提出的两阶段母体年龄、形状、大小及各样品埋藏位置的模式是合理的.各样品散裂、放射和俘捕气体的研究表明:气体的丢失机制是第二阶段母体在行星际空间运行时受到太阳的周期性加热.根据Ⅱ号陨石各定位样品的3,4He,20,21,22Ne和40Ar的研究,恢复了Ⅱ号陨石在两阶段母体中的相对位置.

关键词：宇宙线第一阶段吉林陨石核素深度分布

Multimodal 4-arylchromene derivatives with microtubule-destabilizing,anti-angiogenic,and MYB-inhibitory activities

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Cancer Drug Resistance 2023年第1期6卷 59-77页

作者： Leonhard H.f.Kohler Sebastian Reich Maria Yusenko Karl-Heinz Klempnauer Gerrit begemann Rainer Schobert Bernhard Biersack Organic Chemistry Laboratory University of BayreuthBayreuth 95440Germany Institute for Biochemistry Westfalische-Wilhelms-UniversitatMunster 48149Germany Developmental Biology University of BayreuthBayreuth 95440Germany

Aim:Efficient and readily available anticancer drugs are sought as treatment *** this reason,chromene derivatives were prepared using the one-pot reaction and tested for their anticancer and anti-angiogenic ***:2-Amino-3-cyano-4-(aryl)-7-methoxy-4H-chromene compounds(2A-R)were repurposed or newly synthesized via a three-component reaction of 3-methoxyphenol,various aryl aldehydes,and *** performed assays to study the inhibition of tumor cell growth[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromid(MTT)assay],effects on microtubules(immunofluorescence),cell cycle(flow-activated cell sorting analysis),angiogenesis(zebrafish model),and MYB activity(luciferase reporter assay).fluorescence microscopy was applied for localization studies via copper-catalyzed azide-alkyne click reaction of an alkyne-tagged drug ***:Compounds 2A-C and 2f exhibited robust antiproliferative activities against several human cancer cell lines(50%inhibitory concentrations in the low nanomolar range)and showed potent MYB *** alkyne derivative 3 was localized in the cytoplasm after only 10 min of *** microtubule disruption and G2/M cell-cycle arrest were observed,where compound 2f stood out as a promising microtubule-disrupting *** study of anti-angiogenic properties showed that 2A was the only candidate with a high potential to inhibit blood vessel formation in ***:The close interplay of various mechanisms,including cell-cycle arrest,MYB inhibition,and anti-angiogenic activity,led to identifying promising multimodal anticancer drug candidates.

关键词： Chromene pyran anticancer drugs microtubule angiogenesis MYB inhibition

地球物质和地外物质中稀有气体的研究为什么要研究以及如何进行研究?

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地球与环境 1983年第4期 62-64页

作者： f. begemann,周卫健西德马普学会曼因兹化学研究所

稀有气体在陨石研究中总是起着重要的作用。作为一种介绍,让我举两个例子来证明这一点。 1898年Ramcay在其论文中报道他企图在铁陨石中找到氦元素。因为那时氦元素已被人们所发现,并且被认为是我们太阳系的主要组份。然而他在一些铁陨... 详细信息

稀有气体在陨石研究中总是起着重要的作用。作为一种介绍,让我举两个例子来证明这一点。 1898年Ramcay在其论文中报道他企图在铁陨石中找到氦元素。因为那时氦元素已被人们所发现,并且被认为是我们太阳系的主要组份。然而他在一些铁陨石中并未找到氦,于是宣布,这些特殊的陨石不是来自太阳而是来自其它星球。今天我们认为,这一结论至少是很不成熟的。第二个例子是一个近期的例子。有些种类的陨石长期以来被认为含有大量的稀有气体。在过去的几年

关键词：自发裂变放射性稀有气体同位素丰度比诱发裂变铁陨石物质同位素组成地球行星

DEPTH DISTRIBUTION Of COSMOGENIC NUCLIDES IN BORING CORE SAMPLES Of JILIN METEORITE AND ITS COSMIC RAY IRRADIATION HISTORY

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Science China Mathematics 1987年第8期 885-896页

作者：欧阳自远,范彩云,易惟熙,王先彬,f. begemann,T. KERSTEN,G. HEUSSER,E. PERNICKA Institute of Geochemistry Academia Sinica Guiyang Institute of Geochemistry Academia Sinica Guiyang Institute of Geochemistry Academia Sinica Guiyang Lanzhou Institute of Geology Academia Sinica Max-Planck-Institut für Chemie Mainz Max-Planck Institut für Kernphysik Heidelberg Max-Planck Institut für Kernphysik Heidelberg Max-Planck Institut für Kernphysik Heidelberg

Two boring cores were successfully sampled from the Jilin No. 1 meteorite in such a way that they were kept parallel or perpendicular to the surface of the 1st stage parent body, but across the center of the 2nd stage parent body. Cosmogenic nuclides(3He,20, 21, 22Ne,22Na,26Al,53Mn,50Co), radiogenic gases and trapped noble gases in the two cores have been studied in great detail, which has confirmed the two-staged cosmic ray irradiation history proposed by the authors as being typical of the Jilin Meteorite, and also justified our previous models regarding the ages, shapes and sizes of the two parent bodies related to the two stages as well as the emplacement of various samples. Investigations of spallogenic, radiogenic and trapped gases reveal that the periodic heating by the sun of the 2nd-stage parent body was responsible for the gas loss from the body while it was moving in the inter-planet spaces. The relative positions of the No.2 meteorite in the parent bodies of the two stag

关键词： body DEPTH DISTRIBUTION Of COSMOGENIC NUCLIDES IN BORING CORE SAMPLES Of JILIN METEORITE AND ITS COSMIC RAY IRRADIATION HISTORY