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Assembly of gold nanoparticles with H_(10)TTPR (3a, 4, 5. 8, 9, 9a, 10, 11-octa-hydro-2H,3H-1,6,7,12-tetrathia-perylene) as the rigid cross-linker

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chinese Science Bulletin 2004年第8期49卷 789-792页

作者： SHAO Xiangfeng1,2, WANG Tongxin1, ZHANG Deqing1, xu wei 1 & ZHU Daoben1 1. Organic Solids Laboratory, Center for Molecular sciences, institute of Chemistry, chinese academy of sciences, {5. 100080, China 2. Graduate School, chinese academy of sciences, {5. 100080, China correspondence should be addressed to Zhu Daoben or Zhang Deqing (e-mail: dqzhang@***) Organic Solids Laboratory Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100080 China

Gold nanoparticles were assembled with the rigid cross-linker, H10TTPR. The assembly process was stud-ied with the UV-vis spectroscopy and TEM. By adjusting the amount of H10TTPR added to the gold nanoparticle solutio... 详细信息

关键词：纳米金粒子集成刚性交叉连接 TEM UV-力光谱学

Cloning and expressional analyses of a cinnamoyl CoA reductase cDNA from rice seedlings

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chinese Science Bulletin 2003年第20期48卷 2221-2225页

作者： BAI Yong, GONG wei, LIU Tianyun & ZHU Yuxian College of Life sciences, Peking University, Beijng 100871, China correspondence should be addressed to Zhu Yuxian (e-mail: zhuyx@ ***) College of Life sciences Peking University Beijing China

Cinnamoyl CoA reductase (CCR: EC 1.***.1.44), the entry-point enzyme of the lignin specific biosynthetic pathway, catalyzes the conversion of cinnamoyl CoA esters to their corresponding cinnamaldehydes. Multiple sequence alignment showed that the deduced polypeptide shared 70% similarity and 30% sequence identity at the amino acid level with defined CCR genes from other plant species and they all contain the common signature sequences thought to be the catalytic site as well as the putative NADP binding domain. Using a conserved OsCCR cDNA fragment as the probe for library screening, we isolated the genomic DNA that covered the whole coding region of OsCCR with total length of 3045.bp including 4 introns and 5.exons. The open reading frame for our OsCCR gene contains 337 amino acids. Northern blot indicated that OsCCR was expressed in different organs with the highest level found in stems. In situ hybridization results showed that OsCCR mRNA was localized mainly along the vascular bundles in stems and leaves, and also in lateral roots that was differentiating from the tillering node. We conclude that the vascular-localized expression of OsCCR gene may suggest its possible involvement in lignin biosynthesis. Cloning and characterization of OsCCR will help to clarify how lignifications in plants are regulated and will provide a physical basis for creating genetically engineered rice plants with optimal lignin contents.

关键词：水稻肉桂酰钴还原酶基因基因克隆基因表达 DNA序列分析

Zircon SHRIMP U-Pb dating for the Cangshuipu volcanic rocks and its implications for the lower boundary age of the Nanhua strata in South China

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Science Bulletin 2003年第16期48卷 1663-1669页

作者： WANG Jian1, LI Xianhua2, DUAN Taizhong3, LIU Dunyi4, SONG Biao4, LI Zhongxiong1 & GAO Yonghua5.1. Chengdu institute of geology and Mineral Resources, China Geologi-cal Survey, Chengdu 610082, China 2. Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 5.0640, China 3. Colorado School of Mines, Golden, CO 80401-1887, USA (Present address: Marathon Oil Company, Houston, TX 7705.-2725. USA) 4. institute of geology, chinese academy of Geological sciences, Bei-jing 100037, China 5. Graduate School of the chinese academy of Geological sciences, beijing 100037, China correspondence should be {15. to Wang Jian (e-mail: jianwang@ ***) Chengdu institute of geology and Mineral Resources China Geological Survey Chengdu 610082 China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Colorado School of Mines Golden CO 80401-1887 USA institute of geology Chinese Academy of Geological Sciences Beijing 100037 China Graduate School of the chinese academy of Geological sciences Beijing 100037 China

The continental volcanic rocks and volcaniclas-tic sedimentary conglomerates of the Cangshuipu Formation occur well in Yiyang of Hunan Province, consisting of a wedge-shaped succession of Neoproterozoic strata that over-lie with high-angle unconformity the flysch turbidites of the Lengjiaxi Group in the Upper Mesoproterozoic Eonothem. SHRIMP zircon U-Pb dating gives a weighted mean age of 814 12 Ma for the dacitic volcanic agglomerates from the lowest part of the volcanic rocks in the Cangshuipu Forma-tion. This age is younger than previously reported values of 921—933 Ma for the volcanic rocks from the Cangshuipu Formation. Our new dating represents the lower boundary age of the Neoproterozoic System in the studied area. The younger age for the Cangshuipu volcanic rocks is supported by the following observations: （1） Lower Neoproterozoic strata （814—1000 Ma） are missing in the studied area; （2） the Nanhua rift system was initiated at about 820 Ma; and （3） an age of820 Ma may be taken as the lower boundary tim-ing of the Nanhua System （even Neoproterozoic） in South China.

关键词： Zicon U-Pb dating Neoproterozoic volcanics rift basin Nanhua System.

A new species of Leptocycas (Zamiaceae) from the Upper Triassic sediments of Liaoning Province,China

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Journal of Systematics and Evolution 2010年第4期48卷 286-301页

作者： 1,2,3Jian-wei ZHANG 2Jian-Xin YAO 1Jia-Rui CHEN 1Cheng-Sen LI 1(State Key Laboratory of Systematic and Evolutionary Botany,institute of Botany,chinese academy of sciences,{5. 100093,China) 2(State Key Laboratory of Stratigraphy and Paleontology,institute of geology,chinese academy of Geological sciences,{5. 100037,China) 3(Graduate University,chinese academy of sciences,{5. 100049,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (State Key Laboratory of Stratigraphy and Paleontology Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China) *correspondence: Cheng-Sen LI *Correspondence: ?Author for correspondence. E-mail: lics@*** Tel.: 86-10-6283-6436 Fax: 86-10-625.-3385.

A new cycad,Leptocycas yangcaogouensis ***.,was found in sediments from the Late Triassic in western Liaoning,*** pinnately compound leaves(Pseudoctenis type)are screwed in a crown on the stem *** leaflets are linear,with parallel veins and decurrent bases on the *** leaf bases are *** cataphylls intermix with the *** female cone is ovoid in *** characteristics of the new plant are more similar to those of Leptocycas gracilis,a Triassic cycad from North America,but the new species differs from *** in the size of its stem(7–8 vs.3–5.cm in diameter,respectively),leaves(length×width 100×16 vs.30×7 cm,respectively)and leaf density along the stem(4–6 vs.1–2 bases/1 cm length,respectively).Both *** and ***,having leaves of the Pseudoctenis type,show a closer relationship to the extant Dioon of *** present study provides evidence for the origin of the genus Dioon,which may have come from Leptocycas plants of the *** would be assumed that the extent cycads in Zamiaceae originate from the pteridosperms in the Late Paleozoic and have evolved through the stage of *** and *** in Late Triassic,and reaching the extant Dioon.

关键词： China Cycadales Leptocycas Upper Triassic Zamiaceae

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地电阻率日变化成因分析

地震地质 2019年第6期41卷 1464-1480页

作者：解滔卢军闫伟中国地震台网中心

中国部分长期连续观测的地电阻率台站的观测数据呈现出清晰的日变化形态,依据单一测道的变化特征,日变化可分为2类相反的形态:一类观测数据白天下降夜间上升;另一类则白天上升夜间下降。文中结合含水岩土介质电阻率的影响因素、台站电... 详细信息

中国部分长期连续观测的地电阻率台站的观测数据呈现出清晰的日变化形态,依据单一测道的变化特征,日变化可分为2类相反的形态:一类观测数据白天下降夜间上升;另一类则白天上升夜间下降。文中结合含水岩土介质电阻率的影响因素、台站电性结构和地电阻率影响系数理论,分析认为固体潮引起的介质电阻率变化幅度太小,以目前地电阻率观测仪器的分辨率还不足以记录到固体潮的影响,地电阻率的日变化主要由昼夜温差所引起。昼夜温差将使浅层介质电阻率发生大幅度的昼降夜升变化,对于浅层介质影响系数为正的测道,其日变化呈现昼降夜升的形态,而浅层介质影响系数为负的测道,其日变化则呈现出昼升夜降的形态。

关键词：地电阻率日变化成因机理温度固体潮

永定河中下游MIS7以来地层沉积演化及新石器时代以来气候变化

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中国地质 2021年第4期48卷 1188-1199页

作者：赵勇杨誉博李瑞杰杨吉龙王强李亚林王纯君魏波方同明王志辉北京市地质调查研究院北京100195 中国地质调查局天津地质调查中心天津300170 中国地质调查局泥质海岸带地质环境重点实验室天津300170 中国地质大学(北京) 生物地质与环境地质国家重点实验室北京100083 中国地质科学院北京100037

利用廊坊东A27钻孔岩心资料,样品微体生物、孢粉特征综合分析,结合AMS14C测年,对永定河中下游地区MIS7以来的地层进行分析,建立了MIS7以来的沉积地层格架,并对其进行了年代厘定,讨论了该地区大约MIS7阶段以来氧同位素分期气候下的地层... 详细信息

利用廊坊东A27钻孔岩心资料,样品微体生物、孢粉特征综合分析,结合AMS14C测年,对永定河中下游地区MIS7以来的地层进行分析,建立了MIS7以来的沉积地层格架,并对其进行了年代厘定,讨论了该地区大约MIS7阶段以来氧同位素分期气候下的地层及环境效应。结果表明,永定河中下游地区晚第四纪可划分为U1~U8共8个沉积单元,分别对应于MIS1~MIS7以及MIS8晚期的沉积地层,与海洋氧同位素分期有很好的对应关系。U1单元为MIS1形成的湖沼—河谷—泛滥平原沉积,U2单元为MIS2形成硬质黏土(第1硬土层)—下切河谷—湖沼沉积,U3单元为MIS3形成的湖沼—河谷—泛滥平原沉积,U4单元为MIS4形成的河间地块沉积(第2硬土层,暴露失水沉积),U5.元为MIS5.成的湖沼夹分支河道沉积,U6单元为MIS6形成的下切河谷夹短暂湖沼沉积,U7单元为MIS7形成的以湖沼为主沉积,U8单元为MIS8晚期形成的泛滥平原沉积,重塑了MIS7以来沉积环境模式,建立了本区晚第四纪精细年代地层框架。笔者认为永定河中下游在新石器时期以河湖共存为主,在其晚期为湖沼发育达到顶峰,出现泥炭层,直至商周时期后在气候变化影响下湖沼消退转变为泛滥平原面貌,为区域古地理环境及生态修复提供重要参考依据。

关键词：古地理环境新石器时代晚第四纪 MIS7以来地层划分永定河中下游地质调查工程京津冀地区