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Science China(Technological Sciences) 2008年第12期51卷 2208-2212页

作者： ZHANG XiaoDong1,2,YANG HeRun1,XU HuShan2,DUAN LiMin2,HU BiTao1,LI ChunYan2 & LI ZuYu2 1 School of Nuclear Science and Technology,lanzhou university,lanzhou 730000,China 2 Institute of Modern Physics,Chinese Academy of Sciences,lanzhou 730000,China School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

In present paper,a new Micromegas detector is developed,and its time and energy signals are obtained in the figure *** rising time of fast time signal is less than 2 ns due to the very fast collection of avalanche electrons,and the rising time of the energy pulse is about 100 ns,which is corresponding to the total collecting time of the electrons and ions in the avalanche *** counter plateau,energy resolution and the gas gains of the detector have been compared with other groups' experimental results and the Garfield simulation result.

关键词： micro-mesh gaseous structure time and energy signals energy resolution gas gain counter plateau

Studies on Single-electron Oxidation of N-Alkyl-p-Phenylenediamines and Benzidines in Aqueous Acetonitrile by Cyclovoltammetry and ESR Spectroscopy

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Chemical Research in Chinese Universities 1988年第4期 24-31页

作者： Zhang Fa, Gao Zhongli and Liu Youcheng(Department of Chemistry, lanzhou university, lanzhou)Chen Wei(Instrumental Analysis and Research Center of lanzhou university,lanzhou)

It is demonstrated by cyclovoltammetry and ESR spectroscopy that N,N,N,’N,’-tetramethyl; tetraethgl, tetra-n-propyl, tetra-n-butyl-p-phenylenediamine and tetraethyl, tetra-n-propyl-p-benzidine undergo deprotonat ion and two consecutive single electron transfer step CE reaction at electrode in aqueous acetonitrile with the corresponding radical cations as the intermediate. The bivalent cations produced at the electrode react not only with hydroxyl anion in the medium to give quinone but also with the N-alkyl-p-phenylene-diamines or benzidines to produce the corresponding radical cations.

关键词： Cyclovoltammetry ESR N-alkyl-p-phenylenediamine N-alkyl-p-benzidine Electron transfer

N-ALKYLPHENOTHIAZINE RADICAL CATIONS GENERATED IN THE CAVITY OF β-CYCLODEXTRINS IN A(?)UEOUS SOLUTION

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Chinese Chemical Letters 1992年第1期3卷 53-56页

作者： Qing Xiang GUO Ping HUAN Bo LIU You Cheng LIU Depar’ment of Chemistry,lanzhou university,lanzhou 730000

Phenothiazine and i^+s derivatives were oxidized by l_2 and 2,2,6,6-tetrametbyl-4- acetyloxypiperidine oxoammonium hexachloroantimonate to the corresponding radical cations in the cavity of β-cyclodextrins in aqueous... 详细信息

关键词： CD UEOUS SOLUTION CYCLODEXTRINS IN A N-ALKYLPHENOTHIAZINE RADICAL CATIONS GENERATED IN THE CAVITY OF

OFF－LINE　TWO－DIMENSIONAL　GAS　CHROMATOGRAPHY－MASS　SPECTROMETRY　FOR　ANALYSIS　OF　ASSENTAL　OIL　OF　MEDICINAL　HERB：USE　OF　ABSORPTION　TRAP　AS　INTERFACE

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Chinese Chemical Letters 1994年第1期5卷 73-76页

作者： XueYi MA Hui Ping PAN and YaoZu CHEN (National Laboratory of Applied Organic Chemistry and Department of Chemistry,lanzhou university, lanzhou 730000)

The use of an absorption trap off-line 2-DGC in conjunction with a mass spectrometer greatly improved the separation and identification of minor constituents of a complex mixtures such as a natural essential oil. The ... 详细信息

关键词： GAS CHROMATOGRAPHY DIMENSIONAL TWO MASS LINE ABSORPTION

A New 1β-hydroxy-ent-kaurenoid From Isodon Enanderianus

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Chinese Chemical Letters 1998年第8期9卷 733-734页

作者： Yan Hong WANG Yao Zu CHEN Zhong Wen LIN Han Dong SUN (School of Chemistry and Chemical Engineering, Zhongshan university, Guangzhou 510275)(State Key Laboratory of Applied organic Chemistry, lanzhou university, lanzhou, 730000, and Department of Chemi Zhongshan Univ Sch Chem & Chem Engn Canton 510275 Peoples R China lanzhou Univ State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China Chinese Acad Sci Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China

A new 1β-hydroxy-ent-kauren diterpenoid, enanderianin C1, has been isolated from the leaves of Isodon enanderianus, and its structure has been elucidated by spectroscopic evidences.

关键词： labiatae isodon enanderianus ent-kauren diterpene

The Future of English does not belong to Native Speakers

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中学生英语 2010年第11期 40-42页

作者： lanzhou Jiao Tong university lanzhou ZhiChun Zhou lanzhou Jiao Tong university lanzhou

English whether being used as a lingua franca or as an international language,the tendency of English development does not belong to native speakers.

关键词： lingua franca EIL ’three circles’

A novel and efficient total synthesis of(±)-Cembrene-A

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Chinese Journal of Chemistry 1992年第1期10卷 92-94页

作者： LI,Wei-Dong LI,Ying LI,Yu-Lin Laboratory of Applied Organic Chemistry,Institute of Organic Chemistry,lanzhou university,lanzhou 730000 Laboratory of Applied Organic Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 730000

(±)-Cembrene-A,a highly active scent-trail pheromone,was first isolated from thetermite(Nasutitermes exitiosus)and its structure was established by using chemical and spectralmethods,Afterwards,it was also found in some plants and soft *** view of itsbiological activity,some total syntheses have been *** was reported that its dl-form showed the same order of activity as that of the natural pheromone,In previous work,

关键词： A novel and efficient total synthesis of Cembrene-A

A METHOD FOR MECHANICAL GEOMETRY THEOREM PROVING

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Systems Science and Mathematical Sciences 1996年第4期9卷 313-318页

作者： WU Jinzhao(Institute of Systems Science, Academia Sinica, Beijing 100080, China)TAN Hongyan(Dopartment of Computer Science, lanzhou university, lanzhou 730000, China) Institute of Systems Science Academia Sinica Beijing 100080 China ***

ＡＭＥＴＨＯＤＦＯＲＭＥＣＨＡＮＩＣＡＬＧＥＯＭＥＴＲＹＴＨＥＯＲＥＭＰＲＯＶＩＮＧ￥ＷＵＪｉｎｚｈａｏ（ＩｎｓｔｉｔｕｔｅｏｆＳｙｓｔｅｍｓＳｃｉｅｎｃｅ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅｉｊｉｎｇ１０００８０，... 详细信息

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关键词： Wu-Ritt well ordering algorithm prime ideals irreducible characteristic sets

Analysis of Chemical Incredients of Angelica Sinnesis——Analysis of Non-Volatile Constituents of Roots

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Chemical Journal of Chinese Universities 1985年第1期 59-67页

作者： Chen Yaozu and Zhang Huidi (Institute of Organic Chemistry,lanzhou university,lanzhou)

In the present investigation,the non-volatile constituents of Danguei (Tang-Kuei) roots of Gansu origin [Angelica sinensis (Oliv.) Diels] were analyzed and thirty seven organic constituin s were also identified,fifteen of which have not been recorded in literature before,including a new optically active compound named as Angelicide and an antibiotie,Brereldin *** plasma emission spectrometry,thirteen minor elements were also detecled

关键词： Analysis of Non-Volatile Constituents of Roots Analysis of Chemical Incredients of Angelica Sinnesis

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science China Earth Sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2, AN Lizhe1, 3, WU Guangjian2, XU Baiqing2, MA Xiaojun 3, LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, China 2. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 3. College of Life Science, lanzhou university, lanzhou 730000, China Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China College of Life Science lanzhou university lanzhou China

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.