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Population information extraction in Chaohu watershed based on RS and GIS

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chinese Science Bulletin 2003年第2期48卷 181-183页

作者： liu j.anj.n1,2 & LI Chunlai3.1. Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, {3. 2. Graduate School, chinese academy of sciences, beijing 10003., {3. 3. national astronomical observatories, chinese academy of sciences, beijing 100012, china correspondence should be addressed to liu j.anj.n (e-mail: dhsliujj@ ***) Institute of Geochemistry Chinese Academy of Sciences Guiyang China Graduate School Chinese Academy of Sciences Beijing China national astronomical observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价

Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in china

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 173-181页

作者： HAn Yanben1, GUO Zengjian1,2, WU jinbing1,2 & MA Lihua1 1. national astronomical observatories,{3., beijing 100012, china 2. Earthquake Research Institute of Lanzhou, CSB, Lanzhou 73.00, china correspondence should be addressed to Han Yanben (email: hyb@***) national astronomical observatories Chinese Academy of Sciences Beijing China Earthquake Research Institute of Lanzhou CSB Lanzhou China

This paper studies the relationship between solar activity and big earthquakes (Ms≥8) that occurred in china and western Mongolia. It is discovered that the occurrence dates of most of the big earthquakes in and near faults with west-east strike are close to the maximum years of sunspot numbers, whereas dates of some big earthquakes which are not in such faults are not close to the maximum years. We consider that it is possibly because of the appearance of many magnetic storms in the maximum years of solar activity. The magnetic storms result in anomalies of geomagnetic field and then produce eddy current in the faults gestating earthquake with near west-east strike. Perhaps the gestated big earthquakes occur easily since the eddy current heats the rocks in the faults and therefore decreases the shear resistant intensity and the static friction limit of the rocks .

关键词： earthquake, solar activity, magnetic storm, eddy current.

Differential rotation of geomagnetic field

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chinese Science Bulletin 2003年第24期48卷 2739-2742页

作者： WEI Zigang & XU Wenyao Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china {3. should be addressed to Wei Zigang (e-mail: magstorm @***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The latitudinal dependence of the westward drift in the main geomagnetic field is examined by using the correlation analysis of moving random pattern. The study reveals the characteristics in the differential rotation of the main field. The results show that the global geomagnetic field drifts westward with an average speed of 0.18/a during 1900—2000. The westward drift rate is not symmetrical with re-spect to the equator. The maximum westward drift rate, 0.3./a, occurs at the latitude j = -15? forming a Rapid Westward Drift Belt (RDB) around this latitude. Going northward and southward from this belt, the drift rate de-creases and reaches the minimum (0.12/a) at j = 50?and the minimum (0.14/a) at j = -56? forming a northern Hemi-sphere Slow Westward Drift Belt (n-SDB) and a Southern Hemisphere Slow Westward Drift Belt (S-SDB). Three phases can be detected in the evolution of the westward drift. In the first phase (1900—1940), the RDB dominates the global drift pattern. The westward drifts in this belt are much faster than those in other areas. In the second phase (1940—1960), the drift rates in the RDB are less than those in the first phase, while the drifts in the n-SDB and S-SDB are relatively large. In this phase, the differential rotation becomes less obvious. In the third phase (1960—2000), the westward drift in the RDB increases again and the differen-tial rotation gradually becomes apparent.

关键词：地磁场赤道快速西移带 RDB

Determination of chinese mobile SLR sites'coordinates

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chinese Science Bulletin 2003年第21期48卷 2300-2302页

作者： FEnG Chugang, CAI Wusan, ZHU Yuanlan & YAnG Fumin Shanghai astronomical Observatory, chinese academy of sciences Center for Astro-Geodynamical Research, chinese academy of sciences, Shanghai 20003., {3. correspondence should be addressed to Feng Chugang (e-mail: fcg@***) Shanghai astronomical Observatory Chinese Academy of Sciences Shanghai China Center for Astro-Geodynamical Research Chinese Academy of Sciences Shanghai China

The geocentric coordinates of three mobile sites including Fangshan in beijing, Urumqi in the Xinjiang Uy-gur Autonomous Region and Lhasa in Tibet are determinedin the ITRF2000 frame by means of both the global SLRdata and the mobile (SLR) data obtained by a mobile satel-lite laser ranging (SLR) apparatus from Aug. 2000 to Dec.2001. The results showed that the geometrical performance of chinese SLR network has been significantly improved.

关键词：中国卫星激光修正设备数据处理几何学

Cytokinin signal transduction:Known simplicity and unknown complexity

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chinese Science Bulletin 2003年第13期48卷 1309-1315页

作者： ZHEnG Binglian, SUn jiaqiang, ZHAnG Suzhi, DEnG Yan & ZUO jianru Institute of Genetics and Developmental Biology, chinese academy of sciences, beijing 100101, china {3. should be addressed to Zuo jianru (e-mail: jrzuo@ ***) Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China

Cytokinin plays a critical role in plant growth and development by regulating cell divisions and cell differentiation. Recent studies suggest that cytokinin signaling is presumably mediated by a two-component system analogous to those found in bacteria and fungi, which transduces an external signal via a phosphorelay from the plasma membrane-anchored receptors to downstream effectors and regulators. Moreover, cytokinin signaling is highly interactive with other pathways, and many components of the pathway appear to be functionally redundant. Proper address of these questions will be crucial for our further understanding on this important network.

关键词：细胞分裂素信号转换植物生长基因突变

Study on the coating of nano-scale SiO_2 film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science china Chemistry 2005年第2期48卷 107-114页

作者： ZHAnG Zejiang1,2,3. MEI Xiujuan2, XU Chenghua1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese academy of sciences, Chengdu 610041, china 2. Sichuan Fire Research Institute of Public Security Ministry, Chengdu 61183., china 3. Graduate School of the chinese academy of sciences, beijing 10003., china correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu China Sichuan Fire Research Institute of Public Security Ministry Chengdu China Graduate School of the chinese academy of sciences Beijing China

The coating process of a nano-scale SiO2 film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2film with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HnO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2p, Mg 2p, Si 2s and O 1s on the coated particles indicate that the coating of the SiO2 nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2-coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2on the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 244.67℃ and 43..13., whose corresponding heat absorption capacities are 412.28 j/g and 3.6.3. j/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 243.60℃ with a heat absorption capacity of 221.25 j/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

Approaches to improving critical current density of YBCO superconducting thick films deposited by electrophoresis

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 165-172页

作者： ZHU Yabin1,2, ZHOU Yueliang2, liu Zhen2, WAnG Shufang2, CHEn Zhenghao2, L?Huibin2, YAnG Guozhen2, XIAO Ling3. REn Hongtao3. jIAO Yulei3.& ZHEnG Minghui3.1. Department of Physics, College of Science, beijing jiaotong University, beijing 100044, {3. 2. Laboratory of Optical Physics, Institute of Physics and Center for Condensed Matter Physics, chinese academy of sciences, beijing 100080, {3. 3. General Research Institute for nonferrous Metals, beijing 100088, {3. correspondence should be addressed to Zhu Yabin (email: ybzhu@***) Department of Physics College of Science Beijing Jiaotong University Beijing China Laboratory of Optical Physics Institute of Physics and Center for Condensed Matter Physics Chinese Academy of Sciences Beijing China General Research Institute for nonferrous Metals Beijing China

Fabrication of YBCO superconducting thick films by electrophoresis has been widely reported. However, the value of critical current density (j c) is far from what the practical application requires. The superconducting thick films are obtained using top-seeded melt growth method with different proportional Y2BaCuO5 (Y211) addition. High-pressure oxygen has been used in the annealing process to improve the uniformity of the oxygen content in the superconducting thick films. When 40mol% Y211 powder is added to the YBa2Cu3.7–5 (Y123. powder,j c for the superconducting thick film by approaches described above reaches 7.008×103.A/cm2 (77 K, 0 T), which is greater than the value ever reported.

关键词： YBCO thick films, electrophoretic deposition, melt-textured.

Transgene inheritance and quality improvement by expressing novel HMW glutenin subunit (HMW-GS) genes in winter wheat

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chinese Science Bulletin 2003年第8期48卷 771-776页

作者： ZHAnG Xiaodong, LIAnG Rongqi, CHEn Xqing, YAnG Fengping & ZHAnG Liquan beijing Agro-Biotechnology Research Center, beijing academy of Ag-ricultural & Forestry Science, beijing 100089, china correspondence should be addressed to Zhang Xiaodong (e-mail: zhangxd@***) beijing Agro-Biotechnology Research Center Beijing Academy of Agricultural and Forestry Science Beijing 100089 China

The expression vector pBPC3., which carries the high molecular weight glutenin subunit (HMW-GS) 1Dx5 and 1Dy10 genes, was transferred into hexaploid winter wheat cv. jinghua no. 1, jing411 and jingdong no. 6 ex-plants of immature embryos and immature inflorescence by particle bombardment. A large number of resistant trans-genic plants were obtained under the selection of herbicide bialaphos or phosphinothricin (PPT). Confirmed transgenic plants of T0 generation showed successful integration of HMW-GS genes and bar gene into the wheat genome. T1 generation of transgenic plants can resist 20150 mg/L PPT. Protein analysis of T2 seed by SDS-PAGE showed that HMW-GS 1Dx5 and 1Dy10 genes were well expressed in offspring seed of transgenic lines by co-expression with or substitution of endogenous 1Dx2 or 1Dy10. In one transgenic line, TG3.74, a new protein band between endogenous pro-tein subunits 7 and 8 (marked as 8*) of glutenin appeared, but endogenous subunit 8 (encoded by 1By8 gene) was ab-sent. Analysis of gluten rheological quality on seed proteins of 102 T3.plants showed that the sedimentation value of 5 transgenic lines (44.249.0 mL) was remarkably improved, 59.6%64.3. higher than that of wild type jinghua no. 1 and jingdong no. 6, similar to bread wheat Cheyenne (48.0 mL). Analysis of dough rheological properties of transgenic lines showed that the dough stable time of 5 transgenic lines range from 16 to 3. min, whereas the dough stable time of wild type was only between 3. min. Our research suggests that introducing novel HMW-GS genes into wheat is an effi-cient way to improve its bread-making quality.

关键词：转基因技术麦谷蛋白冬小麦基因表达

novel ^(99m)Tc labeled σ r eceptor ligand as a potential tumorimaging agent

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Science china Chemistry 2006年第2期49卷 169-176页

作者： FAn Caiyun1, jIA Hongmei1, Deuther-Conrad Winnie2, Brust Peter2, Steinbach j?rg2 & liu Boli1 1. Key Laboratory of Radiopharmaceuticals (beijing normal University), Ministry of Education, Department of Chemistry, beijing normal University, beijing 100875, china 2. Institute of Interdisciplinary Isotope Research, Permoserstr. 15, 043.8 Leipzig, Germany correspondence should be addressed to liu Boli Key Laboratory of Radiopharmaceuticals (beijing normal University) Ministry of Education Department of Chemistry Beijing Normal University Beijing China Institute of Interdisciplinary Isotope Research Leipzig Germany

A novel ^(99m)Tc labeled complex,[n-[2-((2-oxo-2-(4-(3.phenylpropyl)piperazin-1-yl)ethyl)(2-mercaptoethyl)amino)acetyl]-2-aminoethanethiolato]Technetium(Ⅴ) oxide (PPPE-MAMA''-^(99m)TcO)([^(99m)Tc]-2) has been designed and prepared based on the integrated approach. The correspondingrhenium complex (PPPE-MAMA''-ReO)(Re-2) has been prepared and characterized. In vitro competitionbinding assays show moderate affinity of Re-2 towards σ_1 and σ_2 receptors with K_i values of8.67 ± 0.07 and 5.71 ± 1.88 μmol, respectively. Planar images obtained at 0.5 h, 4 h, 20 h afteri.v. injection indicate the accumulation of [^(99m)Tc]-2 in MCF-7 human breast tumor bearing mice at20 h. Furthermore, the accumulation of [^(99m)Tc]-2 has been inhibited at 20 h after co-injectionof [^(99m)Tc]-2 plus haloperidol (1 mg/kg). Biodistribution studies of [^(99m)Tc]-2 display an invivo tumor uptake of 0.14% ± 0.01% ID/g at 24 h post i.v. injection with a tumor/muscle ratio of6.02 ± 0.87. The above results suggest that [^(99m)Tc]-2, derived from a previously published leadcompound, retains certain tumor uptake and affinity for σ receptors. [^(99m)Tc]-2 may be used as abasis for further structural modifications to develop tumor imaging agents with high affinity for σreceptors.

关键词： tumor σ receptor SPECT ^(99m)Tc