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Miocene Bahean stratigraphy in the Longzhong Basin, northern central China and its implications in environmental change

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Science China Earth Sciences 2006年第12期49卷 1270-1279页

作者： LI Jijun1,2. ZHANG Jun1, SONG Chunhui1, ZHAO Zhijun2. ZHANG Yong1, WANG Xiuxi 1, ZHANG Jianming1 & CUI Qiaoyu1 1. Key Laboratory of Western China’s Environmental Systems (Ministry of Education) & college of Earth and Environment Sciences, Lanzhou {2., Lanzhou 730000, China 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of Geography, Nanjing normal {2., Nanjing 2.0097, China Key Laboratory of Western China’s Environmental Systems (Ministry of Education) & college of Earth and Environment Sciences Lanzhou University Lanzhou China Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of Geography Nanjing Normal University Nanjing China

Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central China. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental change, we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 10.54―10.30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (11.67―10.40 Ma) at the bottom, floodplain deposits in the middle (10.40―9.2. Ma) and shallow lake sediments at the top (9.2.―7.43 Ma). This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and climatic environment was found at 7.4―7.7 Ma when paleoclimate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response

关键词： Bahean stage,magnetostratigraphy,Yaodian Formation,Neogene,Longzhong Basin.

Gene flow from transgenic oilseed rape (Brassica napus L.) to cruciferous weeds under mentor pollen inducement

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Progress in Natural Science:Materials International 2007年第11期17卷 1284-1289页

作者： Zhao Xiangxiang1,2. Luo Yuming1, Lu Weiping2. Qi Cunkou3, Pu Huiming3 and Wang Youping2.1. Biotechnology Key Laboratory of Eco-agriculture in Hongze Lake Region, Jiangsu Province, Huaiyin normal college, Huai'an 2.3001, China 2. Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou university, Yangzhou 2.5009, China 3. Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 2.0014, China) Biotechnology Key Laboratory of Eco-agriculture in Hongze Lake Region Jiangsu Province Huaiyin Normal College Huai'' an 223001 China Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology Yangzhou University Yangzhou 225009 China Institute of Industrial Crops Jiangsu Academy of Agricultural Sciences Nanjing 210014 China

The alien gene flow between genetically modified glyphosate-resistant rapeseed variety Q3 (Brassica napus L.) and four cruciferous weeds was studied under mentor pollen inducement. The results showed that when Thlaspi arvense L., Capsella bursa-pastoris (L.) Medic, Cardamine hirsuta L. and Rorippa palustris (L.) Besser were pollinated with mentor pollen, the mixed Q3 and the weed, pollen grains aggregated largely and germinated quickly, and the numbers of pollen tubes penetrating into the style and the ovary were greatly increased as compared with corresponding self-pollination groups. Twenty four to forty eight hours after pollination, several pollen tubes were observed to penetrate into the ovule via micropyle in each mentor combination. However, when the mentor progenies were analyzed by PCR, all of them showed negative for the Q3 herbicide-resistant gene. Collectively, these results indicated that crossing between T. arvense, C. bursa-pastoris, C. hirsuta, R. palustris (as female) and Q3 (as male) was highly incompatible and the herbicide-resistant gene could not flow from Q3 to these four weeds.

关键词： herbicide-resistant rapeseed cruciferous weeds mentor pollination aniline blue fluorescence gene flow

Applications of functionalized ionic liquids

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Science China chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1, ZHAO Dongbin2.3, FEI Zhaofu2.& WANG Lefu1 1. Department of Chemical Engineering, Guangdong Provincial Laboratory of Green Chemical Technology, South China Uni-versity of Technology, Guangzhou 510641, China 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1015 Lausanne, Switzerland 3. PKU Green chemistry Center, Beijing National Laboratory for Molecular Sciences, college of chemistry and Molecular Engineering, Peking university, Beijing 100871, China Department of Chemical Engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou China Lausanne EPFL Swiss Federal Institute of Technology Lausanne Switzerland PKU Green chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green {2., but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization

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 {2.), Ministry of Education, Department of chemistry, Beijing normal {2., Beijing 100875, China 2. Institute of Interdisciplinary Isotope Research, Permoserstr. 15, 04318 Leipzig, Germany Correspondence should be addressed to Liu Boli Key Laboratory of Radiopharmaceuticals (Beijing normal {2.) 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, 2. h afteri.v. injection indicate the accumulation of [^(99m)Tc]-2.in MCF-7 human breast tumor bearing mice at2. h. Furthermore, the accumulation of [^(99m)Tc]-2.has been inhibited at 2. 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 2. 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

High resolution stalagmite δ18O records over the past 1000 years from Dongge Cave in Guizhou

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Science Bulletin 2005年第10期50卷 1003-1008页

作者： HE Yaoqi1, WANG Yongjin1, KONG Xinggong1 & CHENG Hai2. 1. college of Geography Science, Nanjing normal university, Nanjing 2.0097, China 2. Department of Geology and Geophysics, Minnesota university, Mineapolis MN 55455, USA college of Geography Science Nanjing Normal University Nanjing 210097 China

Based on MC-ICP-MS U-series dating and stable O-isotope analysis results, a 4―5 years resolution monsoon record over the past 1000 years has been estab- lished for two stalagmites from Dongge Cave, Guizhou. The high resolution oxygen isotope record serves as a proxy for variations in rainfall of Asian southwest monsoon over the Yunnan-Guizhou Plateau. A close relation of the δ 18O record with the ?14C record from tree rings largely reflects impact of centennial-scale solar activity on the monsoon climate changes. The conspicuous decrease in the δ 18O value at AD 172. indicates an abrupt increase in monsoon rainfall, sug- gesting that an atmospheric-oceanic couple over the tropical Indian Ocean plays an important role in rapid increase of the Northern Hemisphere temperature over the last century.

关键词： cave stalagmite oxygen isotope southwest monsoon solar activity Guizhou.

Meet Our New Editorial Board Members of Spotlights

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Chinese Journal of chemistry 2024年第16期42卷 1932-1936页

作者： Editorial Office of Chinese Journal of chemistry 不详

Editorial Board Member of *** ***,college of Materials Science and Engineering Beijing university of Chemical ***:2.06-2.10,B.S.,Materials Science and Engineering,Beijing university of Chemical Technology.2.10-2.15,Ph... 详细信息

关键词： Spotlight Editorial Board

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science China Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4, YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research Center for Remote Sensing and GIS, School of Geography, Beijing {2. university, Beijing 100875, China 2. State Key Laboratory of Remote Sensing Science, Beijing 100875, China 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing 100875, China 4. Department of Information Management, college of Information and Electronic Engineering, China Agricultural university, Beijing 100083, China Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Physiological and ultralstructural changes of Chlorella sp. induced by UV-B radiation

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Progress in Natural Science:Materials International 2005年第8期15卷 678-683页

作者： YU Juan1, TANG Xuexi1*, ZHANG Peiyu 1,2. TIAN Jiyuan1 and DONG Shuanglin1(1. Division of Life Science and Technology, Ocean university of China, Qingdao 2.6003, China 2. {2. of Life Sciences, Qufu normal university, Qufu 2.31653, China) Division of Life Science and Technology Ocean University of China Qingdao 266003 China. college of Life Sciences Qufu Normal University Qufu 2731653 China

In order to investigate the mechanisms of enhanced UV-B radiation on algae, the effects of UV-B radiation on the physiological and ultrastructural changes of Chlorella sp. were examined. The results showed that UV-B radiation could inhibit the growth and photosynthesis of microalgae. UV-B radiation at lower doses increased the photosynthetic pigment (chlorophyll a (Chla) and carotenoid (Car)) contents, while at higher doses of UV-B radiation Chla and Car contents were decreased. The ultrastructure of Chlorella sp. without exposure to UV-B showed that the thylakoid lamellae were clear and regular, the stroma of its chloroplast was apparent and clear. The globules with photosynthetic pigments and the cristae of mitochondria were clearly seen. After exposure to UV-B radiation at dose of 2.88 kJ/m2. the thylakoid lamellae of Chlorella sp. were lost and dissolved, the globules which contained photosynthetic pigments in chloroplast were bleached; some mitochondria cristae were dissolved; slight plasmolysis was found in some Chlorella sp. cells. After exposure to 5.76 kJ/m2.UV-B radiation, the thylakoid was in disarray and disintegration, plasmolysis was found in most cells, and the cell wall was broken and began to fall out. Many blank areas were observed in cells, mitochondria were seriously deformed and most of the mitochondria cristae were dissolved. Also, globules containing photosynthetic pigments in chloroplast were bleached and some empty globules were found in chloroplast. Therefore, UV-B radiation could damage cell structure of Chlorella sp., and this damage increased with the dose of UV-B radiation they exposed to.

关键词： UV-B radiation physiological changes ultrastructure Chlorella sp.

Study on Laccase-Catalyzed Oxidation of Disubstituted Ferrocene and π-arene-π- cyclopentadienyliron Derivatives

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Wuhan university Journal of Natural Sciences 2000年第3期5卷 351-356页

作者： Ji Li-cai1, Hu Pei-zhi2. Jin Chang-hua3 , Ding Zi-rong2.1. college of Adult Education, Wuhan {2., Wuhan 430072. China 2. Col lege of chemistry and Environment Science, Wuhan {2., Wuhan 430072. C hina 3,Yiping Plant of chemistry and Industry at Zhong Qing City, Zhong Qing 63132., China college of Adult Education Wuhan University Wuhan 430072 China college of chemistry and Environment Science Wuhan University Wuhan 430072 China Yiping Plant of chemistry and Industry at Zhong Qing City Zhong Qing 631323China

It is studied that Rhus vernicifera laccase catalyzed oxidation of 2. disubstituted ferrocene and its metal complexes, π-arene-π-cyclopentadienyliron derivatives and metal meso-(tetra-4-sulfanatophenyl)porphyrin in the diethylene glycol monobutyl ether (DGBE)/phosphate buffer (V/V, 1/5). It is found that 1,1′-bishydroxylmethyl ferrocene etc 16 compounds are new substrates of laccase. The relation of structure and function of substrates is discussed. The affective factors of laccase-catalyzed oxidation of 1,1′-bishydroxyl-methyl ferrocene—pH, temperature, substrate concentration, laccase quantity and surfactant were investigated further.

关键词： Key words Rhus vernicifera laccase disubstituted ferrocene catalytic oxidation π arene π cyclopentadienyliron