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Chinese Journal of Chemistry 1996年第3期14卷 252-258页

作者： LIU, You-Cheng REN, Tan GUO, Qing-Xiang National Laboratory of Applied Organic Chemistry, lanzhou University,lanzhou, Gansu 730000, china Department of Modern Chemistry, University of Science and Technology of china,Hefei, Anhui 230026, china National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China Department of Modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China Department of Modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China [*]Address correspondence to this author at University of Science and Technology of china.

A facile method for the title transformation is described. The reaction of 2,2,6,6-tetramethyl-4.methoxypiperidine oxoammonium chloride (1b) and ketones bearing a-methylene group in acetonitrile proceeded smoothly to give the a-oxyfunctionalized coupling products (6a-h). These coupling products decomposed upon heating in acidic medium to produce a-diketones (7a-h) in good to excellent yields.

关键词： Piperidine oxoammonium salt monoketones,α-diketones synthesis

Study on Design and Fabrication of Micro Thermal Control Louvers

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稀有金属材料与工程 2011年第S4期40卷 249-251页

作者： Cao Shengzhu,Chen Xuekang,Wu Gan,Yang Jianping,Wang Rui,Wang Lanxi,Shang Kaiwen Science and Technology on Surface Engineering Laboratory,lanzhou institute of Physics,lanzhou 730000,china lanzhou Inst Phys Sci & Technol Surface Engn Lab Lanzhou 730000 Peoples R China

A micro thermal control device with polyimide based micro louver was *** device structure was designed,the actuation voltage was analyzed theoretically and fabrication process was *** micro louver prototype was fabricated using UV laser micromachining,electrochemistry etch and magnetron sputtering deposition *** main parameters were tested and results were presented.

关键词： micro louvers micromachining thermal control

Ground State Structure of Hs Super-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 properties 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-particle energy level distributions and nucleon occupation,and it is shown to be available to describe the properties of nuclei in the superheavy region.

关键词： superheavy nucleus nuclear structure pairing

Identification and Correction for MT Static Shift Using TEM Inversion Technique

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Journal of china University of Geosciences 2001年第3期12卷 266-271页

作者： Yang ChangfuDepartment of Earth Science, Nanjing University, Nanjing 210093Lin Changyoulanzhou institute of seismology, china Seismological Bureau, {4. Department of Earth Science Nanjing University Nanjing 210093 lanzhou institute of seismology China Seismological Bureau Lanzhou 730000

The inversion of TEM data, using the observed magnetic fields instead of that of apparent resistivities data in this paper, avoids the errors caused by the definition of the apparent resistivity. The inversed results by fitting the magnetic fields of the transmitter source's image with the observed magnetic fields are relatively less affected by the conductivity inhomogeneity. The MT apparent curve is calculated on the basis of the conductivity model constructed from the TEM inversion results. This curve is used as a reference curve for the correction of MT static shift, which makes the correction more reliable. Meanwhile, the domain transformation is also achieved from time to frequency between the two kinds of electromagnetic data. Therefore, the correction of the MT static shift is actualized using TEM inversion method. The corresponding application research shows that this method is very effective for the identification and correction of the MT static shift.

关键词： TEM inversion MT correction of static shift.

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5, SUN Junying4.5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate Center, china Meteorological administration, Beijing 100081, china 2. Climate Change institute, University of Maine, Orono, ME 04.69, USA 3. institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, china 4. Chinese Academy of Meteorological Sciences, Beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research institute, Chinese Academy of Sciences, lanzhou 730000, china 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change institute University of Maine 04469 Orono ME USA 3. institute of Tibetan Plateau Research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. Chinese Academy of Meteorological Sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Three Novel Eremophilanolides from Ligularia virgaurea ***

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Chinese Chemical Letters 2004年第12期15卷 1441-1444页

作者： Quan Xiang WU Yan Ping SHI Li YANG State Key Laboratory of Applied Organic Chemistry, lanzhou University, lanzhou 730000 lanzhou institute of Chemical Physics Chinese Academy of Sciences (CAS) lanzhou 730000 State Key Laboratory of Applied Organic Chemistry Lanzhou University lanzhou institute of Chemical Physics Chinese Academy of Sciences (CAS)

From the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala,three novel eremophilane sesquiterpene lactones, 6α, 10α-dihydroxy-1-oxoeremophila- 7(11),8(9)-dien-8, 12-olide, 6β, 10α-dihydroxy-1-oxoeremophila-7 (11), 8 (9)-dien-8, 12-olide and10α-diydroxy-1-oxoeremophila-7(11), 8 (9)-dien-8, 12 olide were isolated. Their structure s wereelucidated by various, spectroscopic methods including intensive 2D NMR techniques (COSY,HMQC, HMBC and ~1H-~1H NOESY) and HR-MS.

关键词： Ligularia virgaurea spp oligocephala Compositae sesquiterpene lactones eremophilanolides.

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (College of Resources Sciences & Technology, Beijing Normal University, Beijing 100875, china Key Laboratory of Gas Geochemistry, institute of Geology and Geophysics, Chinese Academy of Sciences, lanzhou 730000, china) [a]College of Resources Sciences & Technology Beijing Normal University Beijing China [b]Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Lanzhou China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13C1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4.values available for utilization vary from - 333‰ to - 117‰, and δ13CCO2 values from - 29. 4. to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13C1 and δ13CCO2 values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13C1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.

Acid-base behavior of cryptand 1, 4. 7, 10, 13, 16, 21, 24.octaaza-bicyclo [8, 8, 8] hexacosan-3, 8, 12, 17, 20, 25-hexone and complex formation

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Rare Metals 2002年第1期21卷 12-19页

作者： MO Zunli, CHEN Hong and GAO Jinzhang institute of Chemistry, Northwest Normal University, lanzhou 730070, china institute of Chemistry Northwest Normal University Lanzhou 730070

The bicyclic cryptand 1,4.7, 10,13,16,21, 24.octaaza-bigcyclo [8, 8,8] hexacosan-3, 8, 12, 17, 20, 25-hex-one (COBH) bearing diaminoethane groups along the eight-atom bridges was synthesized. The structure consists of discrete neutral macrobicyclic units; the two cycles share the two tertiary amine nitrogen atoms, which exhibit an endo-cndo conformation. Three identical branches formed by 1, 2-diaminoethane link the two tertiary amine groups. The protonation reactions of cryptand (COBH) and its complex formation with copper (II) were investigated by potentiometry in water and in a DMSO/water (80:20 in mass ratio) mixture as solvents. The cryptand acts as a his-base through its two N-bridgehead and exhibits a strong cooperativity that favors the first protonation and makes the second one difficult (△pK= 5.0). An inward rotation of the amide groups to form hydrogen bonds accounts for this cooperativity. The interaction of COBH with copper (II) leads to several binuclear complex proton contents.

关键词： COBH(cryptand 1,4.7, 10, 13, 16, 21, 24.octaaza-bigcyclo hexacosan -3, 8, 12, 17,20,25 - hex-one) macrobicyclic acid-base behavior complex formation proton contents

Charmed Baryon in Diquark Model

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原子核物理评论 2009年第S1期26卷 190-193页

作者： WANG Qing-wu1,3, ZHANG Peng-ming1,2(1 institute of Modern Physics, Chinese Academy of Sciences, lanzhou 730000, china 2 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Research Facility in lanzhou,lanzhou 730000, china 3 Graduate School of Chinese Academy of Sciences, Beijing 10004., china) institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Graduate School of Chinese Academy of Sciences Beijing 100049China institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China

A diquark model is used to investigate single-charmed baryons. In this model,baryon is composed of two diquarks and an antiquark. Masses of lowest lying states with JP=1/2± are obtained. Baryons in our results are as heavy as other theoretic predictions and we suggest that the five-quark components should be considered in any three-quark model for studying the charmed baryons.

关键词： charm diquark pentaquark

Properties of the 3/2^-[521] band in the odd-N rare-earth nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3 & ZHU LiHua4.1institute of Modern Physics, Chinese Academy of Sciences, lanzhou 730000, china 2Graduate University of Chinese Academy of Sciences, Beijing 10004., china 3State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, china 4.2} institute of Atomic Energy, Beijing 1024.3, china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China4. China Institute of Atomic Energy Beijing 102413 China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[64.], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3/2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model