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Crystal and molecular structure of guanidinium hexatungsto-bis(p-aminophenylarsonate)tetrah ydrate,[C(NH_2)_3]_4[(p-NH_3C_6H_4As)_2W_6O_(25)].4 H_2O

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Chinese Journal of Chemistry 1990年第1期8卷 37-47页

作者： LIU Ben-Yao Yih-Tong KU (GU Yi-Dong) Department of Chemistry,Fudan university,Shanghai 200433WANG Xin Center of Analysis and Measurement,lanzhou university,lanzhou Department of Chemistry Fudan University Shanghai 200433 Center of Analysis and Measurement Lanzhou University Lanzhou

The crystal structure of a new type arylarsonic polytungstate[C(NH_)_]_4[p-NH_3C_6H_4As)_2- W_6O_(25)]·4H_O was determined by single-crystal X-ray diffraction *** belongs to triclinic,space group P,with cell dimensions a=12.863(3),b=18.912(3),c=21.383(4)α=91.14(2)°,β= 93.65(3)°,γ=92.25(3)°,V=5185.9~3,Z=4,D_c=2.753g/cm^*** intensity data were collected on an Enraf-Nonius CAD4 diffractometer with Mo Kα *** positions of all tungsten and arsenic atoms were determined by direct *** other non-hydrogen atoms were revealed by difference Fourier *** structure was refined by fullmatrix least-squares procedure to a final R value of *** crystal structure contains two similar but nonidentical *** similar anions consist of a ring of six WO_6 octahedra,which are connected with one face-sharing,two corner-sharings and three edge-sharings,and two p-aminophenylarsonic tetrahedra capped above and below the ring. In each WO_6 ring,four tungsten atoms,which are joined with edge-sharing oxygen atoms,are almost coplanar,while the two others,which are joined with face-sharing oxygen atoms,protrude out of the ring towards the same *** two arsenic atoms in each anion are not equivalent in their bonding *** each anion,all non-hydrogen atoms of each organic group are in the same *** molecule contains one anion,four C(NH_2)_3^+ cations and four water *** are many hydrogen bonds between cations and anions throughout the whole *** amino groups can accept protons,so that the charge of the resulting anion decreases and[(RAs)_2W_6O_(25)]^(4-)type complexes are formed.

关键词： p-NH3C6H4As Crystal and molecular structure of guanidinium hexatungsto-bis NH2 H2O p-aminophenylarsonate)tetrah ydrate

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Studies on Chemical Constituents of Thermopsis Licentiana(I)——The Structure of A New Alkaloid

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Chemical Research in Chinese Universities 1990年第3期6卷 231-232页

作者： Jia Zhongjian , Song Guangze and Liu Zimin (Institute of Organic Chemistry, lanzhou university, lanzhou)

The Thermopsis genus（Leguminoseae） is comprised of many species, some of which can be used as folk medicine for the treatment of rabies in China. Thermnopsis licentiana is one of the species and has not been studied yet. The present paper reports the separation and identification of a new quinolizidine alkaloid（crystal A;see Fig. 1）.

关键词： Thermopsis licentiana Leguminoseae 13-β-hydroxythermopsine

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Studies on Condensed Heterocyclic Compounds(Ⅲ)——Synthesis and Antibacterial Activity of 3-(4-Pyridyl)-6-Alkyl/Aromatic Heterocyclyl-s-Triazolo[3,4-b]-1, 3,4-Thiadiazoles and 1,4-Bis [6-(4-Pyridyl)-s-Triazolo [3,4-b]-1, 3,4-Thiadiazol-3-yl]-n-Butane

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Chemical Research in Chinese Universities 1991年第2期7卷 129-133页

作者： Zhang Ziyi, Chen Xin, Wei Lulin and Ma Zhaoli (Department, of Chemistry, lanzhou university, lanzhou)

In recent years, fused heterocycles have been reported to possess important properties in synthesis and pharmacology. Especially, s-triazolo, 3,4-thiadiazole derivatives have been attracting much attention for chemists and pharmacologists because they show broad spectra of biological activities, such as antifungal, antibacterial, hy-

关键词： s-Triazolo[3,4-b]-1 ,3,4-thiadiazoles Synthesis Antibacterial activity

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Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2 and Li Jianping2(1. College of Atmospheric Sciences, lanzhou university, lanzhou 730000, China 2. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2005. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

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Crystallization kinetics of (Ni_(0.75)Fe_(0.25)_(78-x)Nb_xSi_(10)B_(12)(x=0,5)amorphous alloys

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Rare Metals 2006年第4期25卷 342-348页

作者： CHEN Xueding WEI Hengdou WANG Xiaojun State Key Laboratory of Advanced New Non-ferrous Materials l.anzhou University of Technology l.anzhou 730050 China

Amorphous ribbons of （Ni0.75Fe0.25）78-xNbxSi10B12 （x = 0, 5） were prepared by a single roller melt-spinning technique in air atmosphere. The crystallization kinetics of the alloys were investigated by means of continuous heating, and the activation energies of the alloys were calculated using Kissinger plot method and Ozawa plot method on the basis of differential thermal analysis data. The crystallization products were analyzed by X-ray diffraction. After the （Ni0.75Fe0.25）78Si10B12 amorphous alloy was annealed at the temperatures 715 and 745 K, a single phase of γ-（Fe, Ni） solid solution with grain sizes of about 10.3 and 18.5 nm, respectively, precipitates in the amorphous matrix. The crystallized phases are γ-（Fe, Ni） solid solution, Fe2Si, Ni2Si, and Fe3B after annealing at 765 K. The （Ni0.75Fe0.25）73NbsSi10 B12 amorphous alloy was annealed at 720, 750, and 800 K; and the crystallization phases, γ（Fe, Ni） solid solution, （Fe, Ni）23B6. Ni31Si12 and Nb2NiB0.16 form simultaneously.

关键词： amorphous materials thermal analysis crystallization kinetics activation energy

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Anomalous Phenomena in E<18 keV Hydrogen Ion Beam Implantation Experiments on Pd and Ti

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Chinese journal of nuclear physics 1997年第4期19卷 244-249页

作者： Wang Tieshan~(1) Piao Yubo~(2) Hao Jifang~(1) Wang Xuezhi~(2) Jin Genming~(1) Niu Zhanqi~(2) (1)Institute of Modern Physics,the Chinese Academy of Sciences,lanzhou 730000 (2)Department of Modern Physics of lanzhou university,lanzhou 730000 中科院近代物理所甘肃兰州兰州大学现代物理系甘肃兰州

Implantation experiments of low energy（1 keVmax1.2 mA/cm2)and lowbeam density(Jmin0.02 mA/cm2).Palladium and titanium foils（plates）are bombarded withproton and deuteron beams in order to compare the atomic and nuclear interactions between dif-ferent ion beams.X-ray and charged particles are measured,and neutron and gamma doses arealso monitored during the implantation *** anomalous peak in X-spectra,whoseenergy is about four times the beam energy,is observed during the high beam density *** peak moves from about 40 keV to 62 keV and FWHM reduces rapidly,while thebeam energy and intensity *** wide peak with over twice the beam energy is mea-sured in experiment with low beam *** is located between 16 keV and 30 keV,and itspeak energy increases with the increase of implantation dose（implantation time）.Some anoma-lous intensities of neutrons correlated with a charged particle peak（2.93,3.85 MeV）are alsoobserved in the deuteron-palladium *** highest neutron intensity reaches about8×104 n/s,while the beam energy and intensity are about 15 keV and 1.0 mA,respectively.

关键词： Hydrogen ion beam Low energy Implantation Palladium and titanium foils

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Terrace dating as an archive of the run-through of the Sanmen Gorges

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Progress in Natural Science:Materials International 2005年第12期15卷 1096-1103页

作者： PAN Baotian,WANG Junping,GAO Hongshan,CHEN Yingying,LI Jijun and LIU Xiaofeng Key Laboratory of Western China’s Environmental Systems,Ministry of Education,and Department of Geography,lanzhou university,lanzhou 730000,China Key Laboratory of Western China''s Environmental Systems Ministry of Education China. Department of Geography Lanzhou University Lanzhou 730000 China

Analysis of morphological properties in the Sanmen Gorges region of the Yellow River shows that four river terraces have been developed at the entrance to the ***,thick aeolian loess-paleosol sequence was deposited on the terraces,which makes it easy to date the *** dating of paleomagnetic,loess-paleosol sequence matching and thermoluminescence show that terraces T2,T3 and T4 were formed 0.129 Ma,0.625 Ma and 0.865 Ma ago,*** formation of these terraces in this region indicates that the Yellow River has experienced four intensive downcutting events during the last 0.9 *** Yellow River cut through the Sanmen Gorges and inpoured into the East China Sea no later than 0.865 Ma.

关键词： river terrace paleomagnetic dating Yellow River loess

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Formation of the [M+NH_4]^+ Ious of Some Mouo-and Di-saccharides in Fast Atom Bombardment Mass Spectrometry

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Chinese Chemical Letters 1997年第10期8卷 879-882页

作者： Jian Jun ZHAI Fau Zhi ZHAO Deug Gang HUANG Yao Zu CHEN (State Key Laboratory of Applied Organic Chemistry , lanzhou university , lanzhou 730000Department of Chemistry , Zhejiang university , Hangzhou 310027)Jin Skan GUO(Gansu Institute of Plast State Key Lab. of Appl. Organ. Chem. Lanzhou University Lanzhou 730000 China Department of Chemistry Zhejiang University Hangzhou 310027 China Gansu Inst. of Plastics and Leather Lanzhou 730000 China

In positive-ion fast atom bombardment (FAB) mass spectrometry, when mono- and di- saccharides are mixed with an appropriate amount of NH4Cl, a highly abundan peak [M+NH4]+appers in FAB mass spectra . From the adduct ... 详细信息

关键词： Mass Atom Ious of Some Mouo-and Di-saccharides in Fast Atom Bombardment Mass Spectrometry M+NH4 Formation of the NH

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Two New Sesquiterpenes from Celastrus ***

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Chinese Chemical Letters 1997年第11期8卷 961-964页

作者： Kun ZHANG Yan Hong WANG Yao Zu CHEN (The State Key Laboratory of Applied Organic Chemistry, lanzhou university,lanzhou. 730000)(Institute of Organic Chemistry, Zhejiang university, Hangzhou,310027)(Guangdong university of Technology,Guangzhau,510090) lanzhou Univ State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China Zhejiang Univ Inst Organ Chem Hangzhou 310027 Peoples R China Guangdong Univ Technol Guangzhau 510090 Peoples R China

Two new beta-dihydroagarofuran sesquiterpene polyol esters were isolated from Celastrus ***. Their Structures were deduced on the basis of spectral analyses including 2D NMR. CO2 supercritical fluid was used in separa... 详细信息

关键词： CDC Two New Sesquiterpenes from Celastrus Paniculatus.Subsp.Paniculatus

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Three-dimensional decomposition method of global atmospheric circulation

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Science China Earth Sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3, HU ShuJuan4, XU Ming5 & CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2 Graduate university of Chinese Academy of Sciences, Beijing 100049, China 3 Beijing Climate Center, Beijing 100089, China 4 Department of Mathematics, lanzhou university, lanzhou 730000, China 5 Shanghai Typhoon Institute, Shanghai 200030, China 6 Department of Atmospheric Sciences, lanzhou university, lanzhou 730000, China 7 China Meteorological Administration Training Center, Beijing 100089, China 1. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate university of Chinese Academy of Sciences Beijing 100049 China 3. Beijing Climate Center Beijing 100089 China 4. Department of Mathematics Lanzhou University Lanzhou 730000 China 5. Shanghai Typhoon Institute Shanghai 200030 China 6. Department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China 7. China Meteorological Administration Training Center Beijing 100089 China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

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