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INVESTIGATION OF THE SURFACE CHARACTERISTICS AND CATALYTIC ACTIVITY OF Sb_xO_y/SiO_2.ATALYSTS FOR VAPOR-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 {2. physics, chinese academy of Sciences, lanzhou, china.)

The surface characteristics and catalytic activity of SbxOY/ SiO2.catalysts forvapor-phasc synthesis of isoprene from isobutylene and formaldehyde have been investi-gated by TPR, XRD, XPS, IR and catalytic activity ev... 详细信息

The surface characteristics and catalytic activity of SbxOY/ SiO2./sub> catalysts forvapor-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 dispersed 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-Sb2./sub>O4 is formed on the support surface and causes rapid de-crease of catalytic activity. It is suggcsted that the catalytic activity of SbxOY /siO2./sub> 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 dispersed crystalline silica gated catalysis synergistic spectrometer photoelectron crease

Effect　of　Catalyst　Pretreatment　on　the　Oxidation　of　Carbon　Monoxide　over　Gold　Catalysts　Supported　on　Double　Oxides

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分子催化 1997年第2期 4-5页

作者： HAO Zhengping AN Lidun 1) WANG Hongli (lanzhou institute of {2. physis The chinese academy of Scienced lanzhou 730000)

ＥｆｅｃｔｏｆＣａｔａｌｙｓｔＰｒｅｔｒｅａｔｍｅｎｔｏｎｔｈｅＯｘｉｄａｔｉｏｎｏｆＣａｒｂｏｎＭｏｎｏｘｉｄｅｏｖｅｒＧｏｌｄＣａｔａｌｙｓｔｓＳｕｐｐｏｒｔｅｄｏｎＤｏｕｂｌｅＯｘｉｄｅｓＨＡＯＺｈｅｎｇｐｉｎ... 详细信息

ＥｆｅｃｔｏｆＣａｔａｌｙｓｔＰｒｅｔｒｅａｔｍｅｎｔｏｎｔｈｅＯｘｉｄａｔｉｏｎｏｆＣａｒｂｏｎＭｏｎｏｘｉｄｅｏｖｅｒＧｏｌｄＣａｔａｌｙｓｔｓＳｕｐｐｏｒｔｅｄｏｎＤｏｕｂｌｅＯｘｉｄｅｓＨＡＯＺｈｅｎｇｐｉｎｇＡＮＬｉｄｕｎ１）ＷＡＮＧＨｏｎ...

关键词： Carbon monoxide oxidation Supported gold catalyst Pretreatment

INVESTIGATION OF THE ACTIVE PHASE OF Ag_xSb_yO_z/SiO_2.CATALYST FOR THE CONDENSATION OF ISOBUTENE AND FORMALDEHYDE INTO ISOPRENE

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分子催化 1989年第S1期3卷 42-50页

作者： An Lidun, Jiang Zhicheng and Yin Yuangen (lanzhou institute of {2. physics, chinese academy of Sciences, lanzhou, china)

chemical Composition,surface distribution of the elements and crystal structure offresh and deactivated AgxSbyOz/SiO2.catalysts were investigated investigated by X-ray photoelectronspectroscopy（XPS）,scanning Auger m... 详细信息

chemical Composition,surface distribution of the elements and crystal structure offresh and deactivated AgxSbyOz/SiO2./sub> catalysts were investigated investigated by X-ray photoelectronspectroscopy（XPS）,scanning Auger microprobc（SAM）,electron microdiffraction（EMD）and atomic absorption spectroscopy（AAS）.From the experimental results that in-clude the activity evaluation of model catalyst Sb2./sub>O4/SiO2./sub> Which Shows the inertness ofSb2./sub>O4 in Prins reaction,it is reasonable to infer that the active phase ofAgxSbyOz/SiO2./sub> catalyst for Prins condensation reaction seems to be cubic AgSbO3.Thereason of the deactivation of the catalyst was *** is suggested that silver componentseems to be unstable in this catalyst.

关键词： silver cubic unstable crystalline condensation Electron dispersed photoelectron spectrometer spacing

A　Methane　Monooxygenase－like　DinuclearIron　（Ⅲ）　Complex　and　its　Catalytic　Ability　for　Asymmetric　Epoxidation　of　Styrene

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chinese chemical Letters 1996年第10期7卷 962-964页

作者： Jun Fa WEI Xian Da YU Dao Sen JIN(lanzhou institute of {2. physics. Academia Sinica, lanzhou 730000) lanzhou Inst. of chemical {2. Academia Sinica Lanzhou 730000

A methane monooxygenase-like dinuclear complex of iron (Ⅲ) with a chiral heptadentate ligand has been synthesed and tested for catalytic ability for asymmetric epoxidation of styrene with iodosylbenzene. The results show that the complex exhibits many qualitative features, such as electronic spectrum. catalytic behavior. and asymmetric induction similar to those of methane monooxygenase and catalyzes styrene epoxidation to R- (+)-styrene oxide in 9. 3% yield and 72. 9% optical yield.

关键词： Ability Asymmetric DinuclearIron Monooxygenase Catalytic

Random Phase Approximation in Relativistic Approach

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原子核物理评论 2009年第S1期26卷 49-54页

作者： MA Zhong-yu1,2.YANG Ding1,TIAN Yuan1,CAO Li-gang2.3(1 china institute of Atomic Energy,Beijing 102.13,china 2.Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Research Facility in lanzhou,lanzhou 730000,china 3 institute of Modern physics,chinese academy of Sciences,lanzhou 730000,china) china institute of Atomic Energy Beijing 102413China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China china institute of Atomic Energy Beijing 102413China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China institute of Modern physics Chinese Academy of SciencesLanzhou 730000China

Some special issues of the random phase approximation(RPA) in the relativistic approach are reviewed. A full consistency and proper treatment of coupling to the continuum are responsible for the successful application of the RPA in the description of dynamical properties of finite nuclei. The fully consistent relativistic RPA(RRPA) requires that the relativistic mean filed (RMF) wave function of the nucleus and the RRPA correlations are calculated in a same effective Lagrangian and the consistent treatment of the Dirac sea of negative energy states. The proper treatment of the single particle continuum with scattering asymptotic conditions in the RMF and RRPA is discussed. The full continuum spectrum can be described by the single particle Green's function and the relativistic continuum RPA is established. A separable form of the paring force is introduced in the relativistic quasi-particle RPA.

关键词： fully consistent RRPA coupling to the continuum pairing correlation

Pollen records of Holocene vegetation and climate changes in the Longzhong Basin of the chinese Loess Plateau

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Progress in Natural Science:Materials International 2007年第12期17卷 1445-1456页

作者： Tang Lingyu1 and An Chengbang2.1. Nanjing institute of Geology and Paleontology, chinese {2. of Sciences, Nanjing 2.0008, china 2. Key Laboratory of Western china’s Environment Systems, MOE, lanzhou University, lanzhou 730000, china) Nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Western china’s Environment Systems MOE Lanzhou University Lanzhou 730000 China

Pollen records with an average time resolution of 2.-2.0 years from Holocene loess sections at Dingxi, Qin'an, and other localities of Gansu Province reveal a detailed history of vegetation and climate changes in the western Loess Plateau. For most time of the Holocene, the landscape was dominated by grasslands or forest steppes. However, during the middle Holocene (7.5-5.8 ka BP), relatively dense forests developed, and the endemic vegetation flourished, suggesting a much warmer and more humid climate condition than the present. Superimposed upon this general pattern are several dry intervals marked by the episodic expansion of grasslands or forest steppe. Xeric vegetation expanded after 3.8 ka BP, indicating a trend towards dry conditions.

关键词： pollen records glasslands coniferous forests Holocene Loess Plateau.

Patterned self-assembled film guided electrodeposition

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Science china Chemistry 2004年第2期47卷 120-125页

作者： ZHOU Feng1, LI Bin1,2. XU Tao1, CHEN Miao1, HAO Jingcheng1 & LIU Weimin1 1. State Key Laboratory of Solid Lubrication, lanzhou institute of {2. physics, chinese academy of Sciences, lanzhou 730000, china 2. Department of Chemistry, Shandong institute of Education, Jinan 2.0014, china 1. State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Department of Chemistry Shandong Institute of Education 250014 Jinan China

The paper describes the fabrication of polypyrrole (PPy) microstructures through patterned self-assembled film guided electrodeposition. Thus the patterned self-assembled monolayer is prepared by microcontact printing (μCP) and used as the template in the electrodeposition of PPy. It has been found that the self-assembled monolayer plays completely different roles on different substrates in directing the deposition of the PPy. Namely, the electrodeposition mainly occurs on the exposed area of the gold substrates patterned with dodecanethiol (DDT) and octadecanelthiol (ODT) and on the indium tin oxide (ITO) substrate patterned with octadecyltrichlorosilane (OTS), while PPy nucleates on the OTS covered area and no deposition is found on the exposed area of a semiconductor substrate (silicon). This is attributed to the co-operative effect between the substrate conductivity and the compatibility of the PPy oligomerwith the covered or exposed area of the substrate surface.

关键词： pattern, conducting polymer, microcontact printing, electrodeposition.

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3 1. china institute of Atomic Energy, Beijing 102.13, china 2. Center of Nuclear Theoretical physics, National Laboratory of Heavy Ion Accelerator of lanzhou, Lan-zhou 730000, china 3. institute of Theoretical physics, chinese academy of Sciences, Beijing 100080, china Correspondence should be addressed to Rong Jian (email: jrong@***) 1. china institute of Atomic Energy 102413 Beijing China 2. Center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou 730000 Lanzhou China 3. institute of Theoretical physics Chinese Academy of Sciences 100080 Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3,4, ZHANG Hucai2. WANG Weiguo3 & AN Chenbang3 1. Nanjing institute of Geology and Palaeontology, chinese {2. of Sciences, Nanjing 2.0008, china 2. Nanjng institute of Geography and Limnology, chinese {2. of Sciences, Nanjing 2.0008, china 3. Environment and Resources College, lanzhou University, lanzhou 730000, china 4. Beijing Normal University, Beijing 100875, china 1. Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal University Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2.to 11 ka B.P. in the Jingning area. Over the period of 44―2. ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2. ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.