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chinese Chemical Letters 1999年第2期10卷 151-154页

作者： Jin Fang WANG Zi Hui MENG Liang Mo ZHOU Qing Hai WANG Dao Qian ZHU(Dalian institute of Chemical Physics, chinese academy of sciences. Dalian 116012) chinese Acad Sci Dalian Inst Chem Phys Dalian 116012 Peoples R China

A highly efficient copolymer (methacrylic acid - co - styrene - divinylbenzene) in situ making high-performance liquid chromatographic column was prepared and evaluated. The column efficiency calculated in terms of height equivalent to a theoretical plate was 25 mu m and rapid separations of small molecules such as substituted aromatic hydrocarbons and aromatic acids were achieved within five minutes.

关键词： highly efficient column poly(methacrylic acid -co styrene-co-divinylbenzene) in situ column substituted aromatic hydrocarbon aromatic acid

Effect of an Alien Species Spartina alterniflora Loisel on Biogeochemical Processes of Intertidal Ecosystem in the Jiangsu Coastal Region,china

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Pedosphere 2008年第1期18卷 77-85页

作者： ZHOU Hong-Xia LIU Jin-E ZHOU Jun QIN Pei Life Science School Nanjing University Nanjing 210093 （China） Kunming institute of botany Chinese Academy of Sciences Kunming 650204 （China）

Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in china almost 3. years ago and has become an urgent topic due to its invasiveness in the coastal zone of china. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.

关键词： alien species biogeochemical processes intertidal ecosystem salt marsh Spartina alterniflora Loisel

MODE Ⅰ CRACK TIP FIELD WITH STRAIN GRADIENT EFFECTS

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Acta Mechanica Solida Sinica 2000年第4期13卷 290-298页

作者： Chen Shaohua Wang Tzuchiang (LNM,institute of Mechanics,chinese academy of {3.,Beijing 100080,china)

A plane strain mode 1 crack tip field with strain gradient effects is investigated.A new strain gradient theory is *** elastic-power law hardening strain gradient material is considered and two hardening laws,i.e.a separation law and an integration law are used *** for the material with the separation law hardening,the angular distributions of stresses are consistent with the HRR field,which differs from the stress results;the angular distributions of couple stresses are the same as the couple stress *** the material with the integration law hardening,the stress field and the couple stress field can not exist simultaneously,which is the same as the conclusion,but for the stress dominated field,the an- gular distributions of stresses are consistent with the HRR field;for the couple stress dominated field,the an- gular distributions of couple stresses are consistent with those in ***,the increase in stresses is not observed in strain gradient plasticity because the present theory is based on the rotation gradient of the deformation only,while the crack tip field of mode 1 is dominated by the tension gradient,which will be shown in another paper.

关键词： crack tip stress field couple stress field strain gradient effect

Regulation of Neutral Lipid Retention by Rab GTPases and Mono-ADP-Ribosylation of CtBP1/BARS

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Regulation of Neutral Lipid Retention by Rab GTPases and Mon...

Paleoclimatic significance of mineral magnetic properties of loess sediments in northeastern Qinghai-Tibetan Plateau

第十一次中国生物物理学术大会暨第九届全国会员代表大会

作者： Pingsheng Liu institute of Biophysics,chinese academy of {3.,Beijing,china

＜正＞Aberration of lipid storage in lipid droplets（LD）has been linked with the development and progression of several common metabolic diseases including obesity,type II diabetes,and

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Paleoclimatic significance of mineral magnetic properties of...

Contribution of Root and Microbial Respiration to Soil CO_2 Efflux and Their Environmental Controls in a Humid Temperate Grassland of Japan

中国科学院地质与地球物理研究所2003.术年会

作者： WANG Xiaoyong~1,LU Huayu~1,LI Zhen~2, DENG Chenglong~3.TAN Hongbing~4 & SONG Yougui~1 1.State Key Laboratory of Loess and Quaternary Geology,institute of Earth Environment,chinese academy of {3.,Xi’an 710075, china 2.Department of Geography,Qinghai Normal University,Xining 810008, china 3.Paleomagnetism Laboratory,institute of Geology and Geophysics, chinese academy of sciences,Beijing 100029,china 4.institute of Saline Lake,chinese academy of {3.,Xining 810008,china

Loess deposit in the northeastern Qing-hai -Tibetan Plateau offers an excellent record of climate and environment changes in this *** have conducted multiparameter mineral magnetic analyses of samples of loess deposits from the Dongchuan,Lalakou and Panzishan sections. The methods used include magnetic susceptibility,frequency -dependent susceptibility,temperature-dependent susceptibility,isothermal remanent magnetization acquisition, and magnetic hysteresis *** results reveal that magnetite is the dominant contributor to magnetic susceptibility. Maghemite and hematite is also present in the loess layers and paleosol *** higher concentration of maghemite in paleosols suggests that the formation of maghemite occurred during in situ pedogenesis,which plays an important role in the enhancement of the magnetic susceptibility. Similar to that in the chinese Loess Plateau lying to the east of the Liupan Mountains,magnetic granulometry in the studied loess and paleosols is predominantly pseudo-single-domain(PSD).However,the mean grain-size of the ferrimagnetic minerals in loess is evidently coarser (larger PSD and multidomain-like) than in paleosols(mainly PSD).The magnetic susceptibility of loess and paleosols is positively correlated with the content of ultrafine magnetite /maghemite grains,and hence with the intensity of in situ ***,the enhanced magnetic susceptibility in the studied loess-paleosol sequences can be interpreted as being due to climatically induced in situ pedogenesis.

关键词： mineral magnetism loess-paleosol Qinghai-Tibetan Plateau magnetic susceptibility

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and Environmental sciences Northeast Normal University Changchun 130024 （China） institute of Biological sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2 efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2005 to reveal seasonal changes of soil CO2 efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2 efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2 effiux and root mass at different experimental sites. Soil CO2 efflux, ranging from 4.99 to 16.29 μmol CO2 m^-2 s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82 and 1.27 kg m^-2 in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-3. cm depth varied from 8 to 180 g m^-2 month^-1. Microbial and root respiration rates ranged from 1.3. to 5.51 and 2.72 to 12.06μmol CO2 m^-2 s^-1, respectively. The contribution of root respiration to the total soil CO2 efflux averaged 53., ranging from 3.% to 72%. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2 = 0.9400, P = 0.002, n = 6）, and the root respiration rate was linearly related to the root production at 0-3. cm depth （R2 = 0.6561, P = 0.042, n = 6）.

关键词： grasslands microbial respiration root production root respiration

Implications of micro-compositions of garnet and biotite from high-grade meta-pelites

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Progress in Natural Science:Materials International 2006年第2期16卷 209-214页

作者： ZHOU Xiwen, WEI Chunjing, and ZHANG Shangkun ( institute of Geology, CAGS, Beijing 10003., china School of Earth and Space sciences, Peking University, Beijing 100871, china china University of Geo-sciences, Beijing 100083. china) institute of Geology CAGS Beijing 100037 China School of Earth and Space sciences Peking University Beijing 100871 China china University of Geo-sciences Beijing 100083 China

Based on detailed studies on the compositional zoning of garnet and biotite in pelitic rocks from the Jingshan group of granulite facies in north Jiaodong, P-T pseudosections with isopleths of Fe/(Fe + Mg) in garnet and biotite were calculated in the KF-MASH system for two representative rocks of sillimanite-garnet-cordierite-biotite gneiss ( Vbi/ Vg>1 ) and sillimanite-garnet gneiss (Vbi/ Vg 1 can nearly preserve their peak compositions, and biotites in garnet-rich rocks with Vbi/Vg<0. 2 cannot preserve their peak compositions due to the influence of grain-boundary fluid.

关键词： high-grade meta-pelites THERMOCALC P-T pseudosection peak compositions of garnet and biotite.

Evidence for metasomatic mantle carbonatitic magma extrusion in Mesoproterozoic ore-hosting dolomite rocks in the middle Kunyang rift, central Yunnan, china

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Progress in Natural Science:Materials International 2008年第8期18卷 965-974页

作者： Yongbei Zhanga,b,c, Hua Bia,*, Longshi Yua, Shihua Sunc, Jiaxiang Qiub, Chengyan Xub, Hao Wang b, Renjing Wang b a The Department of Resources, Environment and Tourism, Hainan Normal University, No. 43., Yinpo Road, Longshepo, Haikou 57000, china b Key Laboratory of Mineral Resources, institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china c Faculty of Earth sciences, china University of Geosciences, Wuhan 470074, china The Department of Resources Environment and Tourism Hainan Normal University No. 432 Yinpo Road Longshepo Haikou 57000 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Faculty of Earth sciences China University of Geosciences Wuhan 470074 China

The Kunyang rift lying on the western margin of the Yangtze platform is a rare Precambrian Fe-Cu mineralization zone. WudingLufeng basin that is an important part of the zone is located on the west edge in the middle of the rift. The most important ore-hosting rocks are Mesoproterozoic dolomite rocks in the basin controlled by a ring fracture system, which is a fundamental structure of the basin. Plenty of silicate minerals and acicular apatite, feldspar phenocrysts and small vesicular, flown line and flown plane structures, melt inclusion and high temperature fluid inclusion found in most ore-hosting dolomites suggest that this kind of rocks could not be sedimentary dolomite, marble or hydrothermal carbonate rocks. The Zr/Hf and Nb/Ta values of the rocks are identical with those of associated mantle-derived rocks, and vary widely. For the monomineral dolomite, d18OSMOW‰ = +5.99 to +18.4 and d13.PDB‰ = à3.01 to +0.94, which fall within the range for all carbonatitic volcanic rocks of the world. As for the accessory minerals, the values of d18OSMOW‰ of magnetite (=+3.47 to +5.99‰) are close to that of the mantle (3.S‰ values of sul?des (à5.09 to +5.78, averaging +1.50) are close to that of meteorite. For all the ore-bearing dolomite rocks, eNd = +0.19 to +2.27, and the calculated ISr = 0.699143. while for the associated mantle-derived rocks, eNd = +3.18 to +3.72. All the data suggest that the mineral assemblage is not only igneous but also of metasomatic mantle origin. And the presence of acicular apatite indicates that the rocks were formed by magma rapidly cooling. And the phenocryst texture and vesicular, flown and ropy and pyroclastic structures suggest that the igneous rocks were extrusive. Therefore, the ore-bearing dolomite rocks are carbonatitic volcanic rocks. This conclusion implies that most iron and copper ore deposits hosted in the dolomite rocks should be of the carbonatite type.

关键词： Central Yunnan Kunyang rift Precambrian Mineralization Carbonatitite Volcanic rocks Petrogenesis Iron and copper ore deposit

Adaptive quasi-likelihood estimate in generalized linear models

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Science china Mathematics 2005年第6期48卷 829-846页

作者： CHEN Xia & CHEN Xiru School of Mathematics and Statistics, Wuhan University, Wuhan 43.072, china Graduate School, chinese academy of Science, Beijing 100049, china 1. School of Mathematics and Statistics Wuhan University 430072 Wuhan China 2. Graduate School Chinese Academy of Science 100049 Beijing China

This paper gives a thorough theoretical treatment on the adaptive quasilikelihood estimate of the parameters in the generalized linear models. The unknown covariance matrix of the response variable is estimated by the sample. It is shown that the adaptive estimator defined in this paper is asymptotically most efficient in the sense that it is asymptotic normal, and the covariance matrix of the limit distribution coincides with the one for the quasi-likelihood estimator for the case that the covariance matrix of the response variable is completely known.

关键词： generalized linear models, quasi likelihood estimate, adaptive estimate.

Simultaneous Chiral Separation Using a Combinatorial Molecular Imprinting Phase

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chinese Chemical Letters 2000年第1期11卷 65-68页

作者： Jin Fang WANG Liang Mo ZHOU Xue Liang LIU Qing Hai WANG Dao Qian ZHU (Dalian institute of Chemical Physics, chinese academy of sciences. Dalian 116012) chinese Acad Sci Dalian Inst Chem Phys Dalian 116012 Peoples R China

Molecular imprinting chiral stationary phase against Cbz-L-Serine (Cbz-L-Ser) and Cbz-L-Alaine (Cbz-L-Ala) were prepared utilizing acrylamide + 2-vinylpyridine as combined basic functional monomers. Cross-selectivity was used to obtain simultaneous chiral separations of Cbz-DL-Ser and Cbz-DL-Ala by connecting two columns packed with Cbz-L-Ser and Cbz-L-Ala imprinted chiral stationary phase, respectively.

关键词： molecular imprinting polymer chiral stationary phase chiral separation