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Properties of the 3/2.-[5.1] 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 {2., Lanzhou 730000, china 2.raduate University of Chinese academy of {2., Beijing 100049, china 3State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, china 4china institute of Atomic Energy, Beijing 102.13, 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 15.Nd(16O, 5.) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5.2.[642., 3/2.[5.1], and 11/2.[5.5. configurations have been extended up to high-spin states, and particularly, the α = -1/2.branch of the ground state 3/2.[5.1] band has been revised significantly. It is found that signature inversion occurs in the 3/2.[5.1] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2.[5.1] 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.[5.1] band.

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

Multi-epoch X-ray observations of the narrow-line Seyfert 1 galaxy SDSS J1605.8.87+32.92..4 with XMM-Newton

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 207-211页

作者： AI YanLi1,2.3,YUAN WeiMin1,2.ZHOU HongYan4,5.& WANG JianGuo1,2.3 1 National Astronomical Observatories/Yunnan Observatory,Chinese academy of {2.,Kunming 65.011,china 2.Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese academy of {2.,Kunming 65.011,china 3 Graduate University of the Chinese academy of {2.,Beijing 100049,china 4 Center for Astrophysics,University of Science and Technology of{12.,Hefei 2.002.,china 5.Joint institute of Galaxies and Cosmology,SHAO and USTC,Shanghai 2.0030,china 1. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China 2. Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China 3. Graduate University of the Chinese academy of sciences Beijing 100049 China 4. Center for Astrophysics University of Science and Technology of China Hefei 230026 China 5. Joint institute of Galaxies and Cosmology SHAO and USTC Shanghai 200030 China

We present results of multi-epoch XMM-Newton observations separated by several years of the narrow-line Seyfert 1(NLS1) galaxy,SDSS J1605.8.87+*** NLS1 showed X-ray flux variations on timescales of years as well as low amplitude variations on timescales as short as hours,while the X-ray spectral shape remained essentially *** spectrum shows a significant soft X-ray *** model of reflection from an ionized disc,that is dominant in the whole XMM-Newton bandpass,provides the best description of the observed spectra for all the observations,though alternatives such as Compton scattering(T-0.2.0}keV) cannot be ruled out in a statistical *** the disc reflection model,the observed variations may originate either from the change in the reflection fraction,or from the variability of the intrinsic X-ray luminosity.

关键词： galaxies:active Seyfert X-rays individual

Synthesis of Racemic 1,2.3,6,7,8,11,12.13-Nonamethoxyl-10,15.dihydro-5.-tribenzo[a, d, g]cyclononene

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Synthesis of Racemic 1,2,3,6,7,8,11,12,13-Nonamethoxyl-10,15...

Soil Microbial Population Dynamics along a Chronosequence of Moist Evergreen Broad-leaved Forest Succession in Southwestern china

中国化学会第四届有机化学学术会议

作者： Yongliang Ding, Bogang Li, Guolin ZHANG chengdu institute of {2., Chinese academy of sciences,{5.

＜正＞Racemic 1,2.3,6,7,8,11,12.13-nonamethoxyl-10,15.dihydro-5.-trbibenzo [a, d, g] cyclononene（NDTC）（1） was synthesized via cyclization of 3,4,5.trimethoxylbenzyl alcohol with Lewis acid catalyst. The effects of Lewis acids and solvents were investigated. The trimerization could be catalyzed by many Lewis acids in CH2.12. such as A1C13 ZnCl2. FeCl3, TiCl4 and SnCl4. Among them, SnCl4 give the highest yield in 5..1%, TiCl4 almost did not catalyzed the cylcization and gave 3,4,5.trimethoxybenzyl chloride as major product. In view of the best effect of SnCl4, it was selected to investigate the effect of solvents. It showed that chlorine-containing solvents benefited the reaction.

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来源： cnki会议评论

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Journal of Mountain Science 2010年第4期7卷 327-338页

作者： ZHU Wanze CAI Xiaohu LIU Xingliang WANG Jinxi CHENG Song ZHANG Xiuyan LI Dengyu LI Maihe institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Sichuan academy of Forestry Chengdu 610081 China Siehuan Agricultural University Yaan 625014 China Swiss Federal Research institute WSL Zuereherstrasse 111 CH-8903 Birrnensdorf Switzerland

Little is known about whether soil microbial population dynamics are correlated with forest *** test the hypotheses that(1) soil microbial composition changes over successional stages,and(2. soil microbial diversity is positively correlated with plant species diversity,we determined the soil microbial populations,community composition,and microflora diversity in evergreen broad-leaved forests along a chronosequence of vegetation succession from 5.to 300 years in southwestern *** soil microbial community was mainly composed of bacteria(87.1-98.7% of the total microorganisms and 10 genera identified),fungi(0.3-4.0%,7 genera),and actinomycetes(2.1-9.1%,8 species and 1 genus).There were significant differences in soil microbial populations among different successional stages and within the four *** seasonal variations of the soil microbial community may be associated with the seasonal changes in environmental *** changes in soil microbial diversity(Shannon-Wiener index) with successional time followed one-humped,convex curves peaked at-100 years since restoration,which is identical with the trends of the aboveground plant *** plant diversity resulting in enhanced nutrient flow and root exudation may contribute to positive relationships between the soil microbial diversity and plant ***,decreases in soil microbial diversity in the late-successional stages appear to be related to the net loss in species richness that occurs after 100 years since *** findings confirm the intermediate disturbance hypothesis that suggests diversity peaks at midsuccessional stages.

关键词： Actinomycetes Bacteria Fungi Microbial diversity Moist evergreen broad-leavedforest Seasonal dynamics

Evolution of cd5. gene in mammals

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Science china(Life sciences) 2007年第6期50卷 773-779页

作者： GONG YuanYing1,2. PENG MinSheng1,2. ZHOU WeiPing1,3,4 & ZHANG YaPing1,4 1 State Key Laboratory of Genetic Resources and Evolution, Kunming institute of Zoology, Chinese academy of {2., Kunming 65.2.3, china 2.Graduate University of the Chinese academy of {2., Beijing 100049, china 3 Molecular and Cell biology, University of Science and Technology of china, Hefei 2.002., china 4 Laboratory for Conservation and Utilization of Bio-resources, Yunnan University, Kunming 65.091, china State Key Laboratory of Genetic Resources Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Graduate University of the Chinese academy of sciences Beijing 100049 China Molecular Cell biology University of Science Technology of china Hefei 230026 China Laboratory for Conservation Utilization of Bio-resources Yunnan University Kunming 650091 China

The CD5.-coding sequences were obtained from 5.mammals by PCR and BLAST, and combined with the available sequences in GenBank, the nucleotide substitution rates of mammalian cd5. were calcu- lated. Results of synonymous and nonsynonymous substitution rates revealed that cd5. experienced negative selection in mammals overall. Four sites experiencing positive selection were found by using "site-specific" model in PAML software. These sites were distributed on the molecular surface, of which 2.sites located in the key functional domain. Furthermore, "branch-site-specific" model detected 1 positive site in cd5.a and cd5.b lineages which underwent accelerated evolution caused by positive selection after gene duplication in mouse.

关键词： cd5., evolution, positive selection

Development of silicon-based microelectrode array

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Science china(Technological sciences) 2009年第8期52卷 2391-2395页

作者： LIN JianHui1,2.3, WU XiaoMing1,2.3,4, HUANG PengSheng1,2. FENG Lei5. REN TianLing1,2.& LIU LiTian1,2.1 institute of Microelectronics, Tsinghua University, Beijing 100084,{2. 2.Tsinghua National Laboratory for Information Science and Technology, Beijing 100084,{2. 3 Yangtze Delta Region institute of Tsinghua University, Jiaxing 31405.,{2. 4 State Key Laboratory of Transducer Technology, Chinese {5. of sciences, Shanghai 2.005. china 5.Department of Biomedical Engineering, Tsinghua University, Beijing 100084,{2. 1. institute of Microelectronics Tsinghua University Beijing 100084 China 2. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China 3. Yangtze Delta Region institute of Tsinghua University Jiaxing 314050 China 4. State Key Laboratory of Transducer Technology Chinese Academy of Sciences Shanghai 200050 China 5. Department of Biomedical Engineering Tsinghua University Beijing 100084 China

This paper introduces in details a kind of silicon-based microelectrode array. MEMS (micro-electromechanical system) technology is used in the fabrication of the microelectrode array, which is designed to perform signal recording and electrical stimulation for nerves in neural engineering. A simple fabrication process is developed. An improved model of microelectrodes is brought forward and successfully validated by the excellent match between circuit simulations and electrical measurements, including both magnitude and phase of microelectrode impedance. Compared with the simple one that is usually used, the improved model is believed to be an advance and more accurate. This modeling helps to improve the design of microelectrodes and understand the behavior of interface between electrode and cell. Furthermore, the microelectrode is proved to be a feasible tool for researches in neural engineering by successfully recording neural activities of sciatic nerve of a bullfrog.

关键词： microelectrode array MEMS neural engineering

Improved retracking algorithm for oceanic altimeter waveforms

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Progress in Natural Science:Materials International 2009年第2期19卷 195-203页

作者： Lifeng Bao,Yang Lu,Yong Wang institute of Geodesy and Geophysics,Chinese academy of {2.,Wuhan 430077,china [a]institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Over the deep oceans without land/ice interference,the waveforms created by the return altimeter pulse generally follow the ocean model of Brown,and the corresponding range can be properly determined using the result from an onboard tracker. In the case of com-plex altimeter waveforms corrupted due to a variety of reasons,the processor on the satellite cannot properly determine the center of the leading edge,and range observations can be in error. As an efficacious method to improve the precision of those altimeter observations with complex waveforms,waveform retracking is required to reprocess the original returning pulse. Based on basic altimeter theory and the geometric feature of altimeter waveforms,we developed a new altimeter waveform retracker,which is valid for all altimeter wave-forms once there exists a reasonable returning signal. The performances of the existing Beta-5.retracker,threshold retracker,improved threshold retracker,and the new retracker are assessed in the experimental regions (china Seas and its adjacent regions),and the improvements in the accuracy of sea surface height are investigated by the difference between retracked altimeter observations and ref-erenced geoid. The comparisons denote that the new algorithm gives the best performance in both the open ocean and coastal regions. Also,the new retracker presents a uniform performance in the whole test region. Besides,there is a significant improvement in the short-wavelength precision and the spatial resolution of sea surface height after retracking process.

关键词： Altimetry Waveform retracking Sea surface height

Models and methods for precise determination of ionospheric delay using GPS

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Progress in Natural Science:Materials International 2007年第2期17卷 187-196页

作者： YUAN Yunbin, HUO Xingliang and OU Jikun ( institute of Geodesy and Geophysics, Chinese academy of {2., Wuhan 430077, china Graduate University of Chinese A-cademy of {2., Beijing 100039, china) [a]Chinese academy of sciences Institute of Geodesy and Geophysics Wuhan China [b]Graduate University of Chinese academy of sciences Beijing China

The basic principles and methods for precisely determining ionospheric delays in GPS observations are introduced and discussed. Various methods and models for fitting ionospheric delays based on GPS are compared and a... 详细信息

关键词： GPS ionospheric delay atmosphere modeling precise GPS positioning.

Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in china

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Science china(Life sciences) 2009年第1期52卷 88-95页

作者： WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2.LUO Chen3,CHU Dong4,ZHANG YouJun4,ZANG LianSheng2.JIU Min2.Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4,ZHANG Fan3,ZHANG QingWen5.LIU WanXue1,LIANG Pei5.LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for {2. of Plant Diseases and Insect Pests,institute of Plant Protection,Chinese Acadeny of Agriculture sciences,Beijing 100094,china 2.institute of Applied Entomology,Zhejiang University,Hangzhou 31002.,china 3 institute of Plant and Environment Protection,Beijing academy of Agricultural and Forestry sciences,Beijing 100089,china 4 institute of Vegetables and Flowers,Chinese Acadeny of Agricullare sciences,Beijing 100081,china 5.Department of Entomology,china Agriculture University,Beijing 100094,china 1. State Key Laboratory for biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Acadeny of Agriculture Sciences Beijing 100094 China 2. institute of Applied Entomology Zhejiang University Hangzhou 310029 China 3. institute of Plant and Environment Protection Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 China 4. institute of Vegetables and Flowers Chinese Acadeny of Agricullare Sciences Beijing 100081 China 5. Department of Entomology China Agriculture University Beijing 100094 China

Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex *** this report,the invasive mechanism and management of *** biotype B,based on our 5.year studies,are *** *** biotypes,B,Q,ZHJ1,ZHJ2.ZHJ3 and FJ1,have been identified in *** B dominates the other biotypes in many regions of the *** diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal *** activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to *** higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host *** adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein *** indigenous *** biotypes were displaced by the biotype B within 2.5.*** asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other *** biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse *** adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of *** ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with *** predatory natural enemies possess greater ability to suppress *** under field *** kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its *** present results provide useful information in explaining the mechanisms of genetic diversity,e

关键词： National Basic Research and Development Program of china(973 Program) invasive alien species Bemisia tabaci biotype B ecological mechanisms genetic diversity sustainable management