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C_(19)-DITErpENOID ALKALOIDS OF DELpHINIUM MOLLIpILUM

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Chinese Chemical Letters 1995年第2期6卷 101-102页

作者： Suo Ming ZHANG Qing Yu Ou(lanzhou institute of Chemical physics, Chinese Academy of Sciences, lanzhou 730000) Chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

Five C19-diterpenoid alkaloids were isolated from the aerial p.r.s of Delphinium mollipilum ***. Four proved to be the known talitine B,talitine A, browniine and delcosine, while the fifth was a new C19-diterpenoid al...

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A possible proton pygmy resonance in ^(17)Ne

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 49-52页

作者： MA ZhongYu1,2 & TIAN Yuan1 1 china institute of Atomic Energy, Beijing 102413, china 2 Center of Theoretical Nuclear physics, National Laboratory of Heavy Collision, lanzhou 730000, china china institute of Atomic Energy Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Collision Lanzhou China

The low-lying electric dipole strengths in proton-rich nuclei 17F and 17Ne, which can be produced at HIrFL-CSr in lanzhou, are investigated. In the framework of the covariant density functional theory the self-consistent relativistic Hartree Bogoliubov model and the relativistic quasip.r.icle random phase ap.r.ximation with the NL3 p.r.meter set and Gogny pairing interaction are adopted in the calculations. A pronounced dipole peak appears below 10 MeV in17Ne, but does not occur in 17F. The prop erties of this low-lying E1 excitation in 17Ne are studied, which may correspond to a proton pygmy resonance with different characteristics from those of giant dipole resonance.

关键词： proton pygmy resonance relativistic Hartree-Bogoliubov model relativistic quasip.r.icle random phase ap.r.ximation

A study on the reaction of 2'-hydroxychalcones with I_2-H_2SO_4-DMSO system

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Chinese Journal of Chemistry 1994年第1期12卷 73-78页

作者： ZHANG, Fang-Jie LI, Yu-LinState Key Laboratory of Applied Organic Chemistry and institute of Organic Chemistry, lanzhou University , lanzhou, Gansu 73000, china State Key Laboratory of Applied Organic Chemistry and institute of Organic Chemistry Lanzhou University Lanzhou Gansu 73000 China

The reaction of 2'-hydroxychalcones with I_2-H_2SO_4-DMSO system has been studied. The results obtained by us are entirely different from those rep.r.ed in the literature. The mechanism of this reaction has also been ... 详细信息

关键词： reaction 2'-hydroxychalcone I_2-H_2SO_4-DMSO system.

NEW TAXANES FrOM TAXUS CHINENSIS.2

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Chinese Chemical Letters 1990年第1期1卷 91-92页

作者： Zong ping ZHANG Zhong Jian JIA institute of Organic Chemistry,lanzhou University,lanzhou 730000,Gansu,p.r.of china

Tow new taxane diterpenes were isolated from the leaves and stems of Taxus *** structures were established as 2-deacctyl-5-decinnamatetaxagifine and taxagifinc Ⅲ on the basis of spectroscopic analysis.

关键词： ppm HNMr NEW TAXANES FrOM TAXUS CHINENSIS.2 Miller

Ground State Structure of Hs Sup.r.heavy Isotopes

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原子核物理评论 2009年第S1期26卷 175-180页

作者： MA Long1,ZHOU Xiao-hong1,ZHANG Hong-fei2,GAN Zai-guo1, LI Jun-qing1,3 (1 institute of Modern physics,Chinese Academy of Sciences,lanzhou 730000,china 2 School of Nuclear Science and Technology,lanzhou University,lanzhou 730000,china 3 Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion research Facility in lanzhou,lanzhou 730000,china) institute of Modern physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China

The ground state prop.r.ies of Hs nuclei studied in the framework of the relativistic mean field theory revealed that more stable isotopes are located on the proton abundant side of the chain. The last stable nucleus to the proton drip line is 256Hs. The most stable unknown Hs nucleus may be 268Hs. The density dependent delta interaction pairing is used to improve the BCS pairing correction,which results in more reasonable single-p.r.icle energy level distributions and nucleon occupation,and it is shown to be available to describe the prop.r.ies of nuclei in the sup.r.eavy region.

关键词： sup.r.eavy nucleus nuclear structure pairing

response of Biomass Spatial pattern of Alpine Vegetation to Climate Change in p.r.afrost region of the Qinghai-Tibet plateau,china

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Journal of Mountain Science 2010年第4期7卷 301-314页

作者： ZHANG Yu WANG Genxu WANG Yibo College of resources & Environment Lanzhou UniversityLanzhou 730000China institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

Alpine ecosystems in p.r.afrost region are extremely sensitive to climate *** determine spatial pattern variations in alpine meadow and alpine steppe biomass dynamics in the p.r.afrost region of the Qinghai-Tibet plateau,china,calibrated with historical datasets of above-ground biomass production within the p.r.afrost region's two main ecosystems,an ecosystem-biomass model was developed by employing emp.r.cal spatialdistribution models of the study region's precipitation,air temp.r.ture and soil *** model was then successfully used to simulate the spatio-temp.r.l variations in annual alpine ecosystem biomass production under climate *** a 0.44°C decade-1 rise in air temp.r.ture,the model predicted that the biomasses of alpine meadow and alpine steppe remained roughly the same if annual precipitation increased by 8 mm p.r.decade-1,but the biomasses were decreased by 2.7% and 2.4%,respectively if precipitation was *** a 2.2°C decade-1 rise in air temp.r.ture coupled with a 12 mm decade-1 rise in precipitation,the model predicted that the biomass of alpine meadow was unchanged or slightly increased,while that of alpine steppe was increased by 5.2%.However,in the absence of any rise in precipitation,the model predicted 6.8% and 4.6% declines in alpine meadow and alpine steppe biomasses,*** response of alpine steppe biomass to the rising air temp.r.tures and precipitation was significantly lesser and greater,respectively than that of alpine meadow biomass.A better understanding of the difference in alpine ecosystem biomass production under climate change is greatly significant with respect to the influence of climate change on the carbon and water cycles in the p.r.afrost regions of the Qinghai-Tibet plateau.

关键词： p.r.afrost change Qinghai-Tibetanplateau Alpine ecosystem Grassland biomass Climate change response model

INVESTIGATION OF THE SUrFACE CHArACTErISTICS AND CATALYTIC ACTIVITY OF Sb_xO_y/SiO_2CATALYSTS FOr VAp.r.pHASE SYNTHESIS OF ISOprENE FrOM ISOBUTYLENE AND FOrMALDEHYDE

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分子催化 1989年第S1期3卷 66-71页

作者： Dang Zhongyuan, Ding Shixing (lanzhou institute of Chemical physics, Chinese Academy of Sciences, lanzhou, china.)

The surface characteristics and catalytic activity of SbxOY/ SiO2 catalysts forvap.r.phasc synthesis of isoprene from isobutylene and formaldehyde have been investi-gated by Tpr, Xrd, XpS, Ir and catalytic activity evaluation. The results show that whenthe Sb loadings are less than about 5 wt%,SbxOY is compIctely disp.r.ed on the surface ofsilica to form a surface compound with Sb（V）=O group and the catalysts have relativelyhigh catalytic activity; when the Sb loadings are more than 5 wt%, in addition to this surfacccompound, the crystalline α-Sb2O4 is formed on the supp.r. surface and causes rapid de-crease of catalytic activity. It is suggcsted that the catalytic activity of SbxOY /siO2 catalystsresults from synetgistic catalysis of the surface compound Sb（V）=O as the basic sites andthe surface silanol Si-OH as the acidie sites. The mechanism of this synergistic catalysis forisoprene production is discussed.

关键词： SUrFACE disp.r.ed crystalline silica gated catalysis synergistic spectrometer photoelectron crease

Shell effect and capture cross sections in the synthesis of sup.r.eavy nuclei

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1489-1493页

作者： DU SaiSai1,2,BIAN BaoAn1,2,3,LIU Min1,2,4,FENG ZhaoQing5,6 & ZHANG FengShou1,2,6 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,College of Nuclear Science and Technology,Beijing Normal University,Beijing 100875,china 2 Beijing radiation Center,Beijing 100875,china 3 School of Science,Jiangnan University,Wuxi 214122,china 4 College of physics and Technology,Guangxi Normal University,Guilin 541004,china 5 institute of Modern physics,Chinese Academy of Sciences,lanzhou 730000,china 6 Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Accelerator of lanzhou,lanzhou 730000,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing China Beijing radiation Center Beijing China School of Science Jiangnan University Wuxi China College of physics and Technology Guangxi Normal University Guilin China institute of Modern physics Chinese Academy of Sciences Lanzhou China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The shell effect is included in the improved isospin dependent quantum molecular dynamics model in which the shell correction energy of the system is calculated by using the deformed two-center shell model. A switch function is introduced to connect the shell correction energy of the projectile and the target with that of the compound nucleus during the dynamical fusion process. It is found that the calculated capture cross sections reproduce the exp.r.mental data quantitatively at the energy near the Coulomb barrier. The capture cross sections for reaction 35 80 Br + 82 208 pb → 117 288 X are also calculated and discussed.

关键词： sup.r.eavy nuclei transp.r. theory shell effect cross sections

recent glacial retreat in High Asia in china and its impact on water resource in Northwest china

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Science china Earth Sciences 2004年第12期47卷 1065-1075页

作者： YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,pU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.institute of Tibetan plateau research,Chinese Academy of Sciences,Beijing 100029,china 2.Cold and Arid regions Environmental and Engineering research institute,Chinese Academy of Sciences,lanzhou 730000,china Chinese Academy of Sciences Institute of Tibetan Plateau Research Beijing China Chinese Academy of Sciences Cold and Arid Regions Environmental and Engineering Research Institute Lanzhou China

Under the impact of climatic warming, the glaciers in the High Asia in china have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in china is that the smallest magnitude of retreat is in the inland of the Tibetan plateau, the magnitude increases from the inland to the margin of the Tibetan plateau, and the largest magnitude at the margin of the Tibetan plateau. The glacial retreat in the High Asia in china has an imp.r.ant impact on the water resource of the arid regions in Northwest china. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest china. In the Tarim river basin, the increase of river runoff is higher than 5.5%.

关键词： High Asia, glacial fluctuation, impact on water resource.