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Comparison of photovoltaic devices based on MEH-PPV with various molecular weights

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Chinese science Bulletin 2004年第21期49卷 2259-2261页

作者： KANG Bonan1,2. WANG Liduo1, YANG Yong1 & QIU Yong1 1. key laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua Univer- sity, Beijing 100084.{2. 2. state key laboratory on Integrated optoelectronics, Jilin University Region, Changchun 13002.,{2. key laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing China state key {2. on Integrated optoelectronics Jilin University Region Changchun China

Polymer photovoltaic devices based on poly (2. methoxy-5-(2. -ethyl-hexyloxy)-1,4.phenylene vinylene) (MEH- PPV) with three weight-average molecular weights (Mw) have been fabricated with the device structure of ITO/PEDOT/ MEH-PPV/Ca/Ag, and the effect of the molecular weight on photovoltaic properties has been investigated. The experi- mental results show that the high molecular weight of MEH- PPV leads to low series resistance (Rs) and high short-circuit current. The low molecular weight of MEH-PPV leads to high shunt resistance (Rsh) and high open-circuit voltage. When the molecular weight is 6×105, the highest power con- version efficiency was observed.

关键词： MEHPPV 分子量光电器件载流子迁移率串联电阻并联电阻聚(2.甲氧基-5-(2.-乙基-乙氧基)-1,4.亚苯基乙烯撑)

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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science china Earth sciences 2006年第10期49卷 1032-1042页

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-137) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4.± 3.0 Ma and 2.0.4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±4. Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Change of surface cover greenness in china between 2.00 and 2.10

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Chinese science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4. GONG Peng1,2.31state key {2. of {4. sensing science, Jointly Sponsored by Institute of {4. sensing Applications of Chinese Academy of sciences,and Beijing Normal University, Beijing 100101, china 2.nstitute for Global Change Studies & Center for Earth System science, Tsinghua University, Beijing 100084. china 3Department of Environmental science, Policy and Management, University of California, Berkeley, CA94.2., USA 4.raduate University of Chinese Academy of sciences, Beijing 10004., china state key {2. of remote {4. science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate University of Chinese Academy of sciences Beijing China Institute for Global Change Studies & Center for Earth System science Tsinghua University Beijing China Department of Environmental science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2.00 to 2.10 and analyzed their change over{2. in this *** results showed that an increasing trend of NDVI occurred over 66.84. (OLS fitting) or 64.2.% (LAD fitting) of{2.,indicating that{2.'s greenness is increasing ***,desertification of{2. *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by climate *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in{2. could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

Sr-Nd isotopic compositions of the Changjiang sediments: Implications for tracing sediment sources

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science china Earth sciences 2007年第10期50卷 1556-1565页

作者： YANG ShouYe1?, JIANG ShaoYong2. LING HongFei2. XIA XiaoPing3, SUN Min3 & WANG DeJie4.1 state key {2. of Marine Geology, Tongji University, Shanghai 2.0092. china 2.state key {2. for Mineral Deposit Research, Nanjing University, Nanjing 2.0093, china 3 Departmen of Earth {14.s, The University of Hong Kong, Hong Kong SAR, china 4.Development Research Center, china Geological Survey, Beijing 100083, china state key {2. of Marine Geology Tongji University Shanghai China state key {2. for Mineral Deposit Research Nanjing University Nanjing China Department of Earth sciences The University of Hong Kong Hong Kong SAR China Development Research Center China Geological Survey Beijing China

The suspended particulate and fine-grained floodplain sediments were collected from the main stream and tributaries of the Changjiang River for Sr-Nd isotopic measurements. The εNd(0) values gradually decrease downstream from -10.8 on average in the upper reaches to -12.3 in the lower reaches, whereas the 87Sr/86Sr ratios increase correspondingly, averaging 0.72.899 and 0.72.82. respectively in the upper and middle-lower reaches. The compositional variations primarily reflect the complex con- trols of provenance rocks, chemical weathering, and sediment characters between different catchments, among which the abnormal Sr-Nd isotopic compositions of the Yalong, Fujiang, Tuojiang and Yuanjiang rivers indicate the sediment provenance contributions from the Emeishan Basalt in the upper reaches and the old metamorphic and siliceous rocks in the middle-lower reaches. The Sr-Nd isotopic ratios of the Changjiang sediments can better reflect the average composition of weathered continental crust compared to other major rivers in the world because of the unique source rock types in the Changjiang drainage basin. The recognition of the Sr-Nd isotopic systematics of the Changjiang sediments will contribute to our understanding of the Changjiang evolution history and continental weathering processes during the Cenozoic, and also to reconstructing the paleoenvironmental changes in East{4. and the marginal seas.

关键词： Sr-Nd isotopes, sediment, Changjiang River, source rock, provenance

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs technique

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Chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. key laboratory of Environmental Change and Natural Disaster, the Ministry of Education of{2., Beijing Normal University, Beijing 100875,{2. 2. Institute of Desert Research, Chinese Academy of sciences, Lanzhou 730000,{2. 3. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 61004.,{2. 4. Department of Physics, Sichuan Union University, Chengdu 61004.,{2. key laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2.376.04.Bq · m-2.wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 4. years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4. S6 and S7) and dry farmlands (S5) suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

2./3D-QSAR comparative study on mutagenicity of nitroaromatics

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science china Chemistry 2005年第3期48卷 246-252页

作者： WANG Xiaodong1, LIN Zhifen2. YIN Daqiang1, LIU Shushen1 & WANG Liansheng1 1. state key {2. of Pollution Control and Resources Reuse, School of the Environment at Nanjing University, Nanjing 2.0093, china 2. key {2. of Tropical Marine Environmental Dynamics, South china Sea Institute of Oceanology, Chinese Academy of sciences, Guangzhou 510301,china state key {2. of Pollution Control and Resources Reuse School of the Environment at Nanjing University Nanjing China key laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

Nitroaromatics are typical toxic organic pollutants and are ubiquitous in environment with diverse structures. They are widely used in many industries and formed during many natural and anthropogenic processes. Most of these pollutants are potentially carcinogenic and the as-sessment and prediction of the mutagenicity of nitroaromatics are of great interest. In this paper the structure-mutagenicity relationships of 2.9 nitroaromatics are investigated by molecular or-bital theory based classic structure-activity relationships and comparative molecular field analysis (CoMFA). A comparison is undertaken in respect of the interpretation of mechanism and predic-tive ability for these two categories of QSAR approaches and highly predictive QSAR models have been developed.

关键词： nitroaromatics, mutagenicity, mechanism, 3D-QSAR, CoMFA.

Archean relic body at lower crust in Sulu area:Evidence from magnetic data

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Chinese science Bulletin 2003年第6期48卷 589-593页

作者： WU Qifan1,2. LU Fengxiang3, LIU Qingsheng3, ZHENG Jianping3, WANG Maoji2.& WU Wenli4.1. Department of Engineering Physics, Tsinghua University, Beijing 100084. china 2. Aero Geophysical Survey & {4. {2. Center, Beijing 100083, china 3. china University of Geosciences, Wuhan 4.0074. china 4. Institute of Geophysical & Geochemical Exploration, Langfang 065000, china Department of Engineering Physics Tsinghua University Beijing China Aero Geophysical Survey & remote sensing Center Beijing China china University of Geosciences Wuhan China Institute of Geophysical & Geochemical Exploration Langfang China

After the new 1︰1000000 aero magnetic data were processed and the three-dimensional inversion work was carried out, a vast high magnetic body northwestward was discovered. The magnetic body is located at the depth of about 2. km on the west side of Tanlu fault and at about 2. km on the east side of Tanlu fault beneath the Sulu area. There is a difference of vertical distance of 3—5 km in depth between both sides. We think that the magnetic body is an Archean metamorphic plate and belongs to the North china block. The discovery of the magnetic body is significant for us to reconstruct the structure model of the Sulu orogenic belt, delineate the suture of collision between the North china block and the Yangtze block, and estimate the depth of slipping surface when the eastside of Tanlu fault moved northward.

关键词：苏鲁地区地壳下层太古代残余体地球物理调查区域性磁场三维反演苏鲁造山带郯鲁断裂带大别-苏鲁超高压变质带

Sr-Nd-Pb isotopes of the Early Paleozoic maficultramafic dykes and basalts from South Qinling belt and their implications for mantle composition

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science china Earth sciences 2007年第9期50卷 1293-1301页

作者： ZHANG ChengLi1,2. GAO Shan1, 2. YUAN HongLin1, ZHANG GuoWei1, YAN YunXiang1, LUO JingLan1 & LUO JinHai1 1 state key {2. of Continental Dynamics, Department of Geology, Northwest University, Xi’an 710069, china 2.state key {2. of Geological Progresses and Mineral Resources, china University of Geosciences, Wuhan 4.0074. china state key {2. of Continental Dynamics Department of Geology Northwest University Xi’an China state key {2. of Geological Progresses and Mineral Resources China University of Geosciences Wuhan China

Late Early Paleozoic mafic-ultramafic dykes and volcanic rocks from the South Qinling belt are char- acterized by εNd( t ) = +3.2.― +5.02. (87Sr/86Sr)i= 0.7034.― 0.70555, (2.6Pb/2.4.b)i = 17.2.6― 18.993, (2.7Pb/2.4.b)i= 15.505―15.64.0} (2.8Pb/2.4.b)i=37.12.―38.968, ?8/4.2..18―774.4., ?7/4.8.11―18.82. These charac- teristics suggest that they derived from a Middle Neoproterozoic mantle with isotopic compositions of mixed HIMU, EMII and minor EMI components. We interpret that these rocks were melting products of depleted mantle modified by subducted ancient oceanic crust and continental margin sediments along the northern margin of Yangtze block during Early Neoproterozoic.

关键词： mafic dykes Sr-Nd-Pb isotope mantle source South Qinling belt

Aoyitake plagiogranite in western Tarim Block, NW china: Age, geochemistry, petrogenesis and its tectonic implications

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science china Earth sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2. YU Haifeng3, YE Haimin2. ZHAO Yu2.& ZHANG Dongsheng4.1. key {4. of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of {2.s, Guangzhou 51064., china 2. Nanjing Institute of Geology and Mineral Resources, Nanjing 2.0016, china 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 300170, china 4. The 2.d Regional Geological Investigation Party, Xinjiang Bureau of Geology and Mineral Resources, Changji 831100, china key laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Nanjing Institute of Geology and Mineral Resources Nanjing China Tianjin Institute of Geology and Mineral Resources Tianjin China The 2.d Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW china. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2.and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4.and 87. Total REE (50-2.0 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2.M model ages of 4.0 to 580 Ma and positive εNd(331 Ma) values of 6.2. to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.