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Microwave Synthesis of CdTe/TGA Quantum Dots and Their Thermodynamic Interaction with Bovine Serum Albumin

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1408-1414页

作者：丁玲 PENG Zeze shen weizhou LIU Tao CHENG Zhengzai GAUTHIER Mario 梁峰 School of Chemistry and Chemical Engineering Coal Conversion and New Carbon Materials Hubei Key Laboratory Wuhan University of Science and Technology Wuhan 430081 China School of Electrical and Eletronic Engineering Huazhong University of Seience and Technology Wuhan 430074 China epartment of Chemistry University of Waterloo Ontario N2L 3G1 Canada

The thioglycollic acid（TGA） as a capping agent, CdTe/TGA quantum dots（QDs） with excellent properties were synthesized under microwave irradiation. The TGA/Cd/Te molar ratios, reaction time, temperature and p H are the crucial factors for properties of QDs. The QDs were characterized by UVvis absorption and fluorescence spectra, transmission electron microscopy and Fourier transform infrared spectroscopy. The experimental results show that when the p H value is 11.5 and molar ratio of TGA：Cd：Te is 1.2：1：0.4 at 100 ℃ heating for 15 min, the resulted QDs exhibit a high fluorescence quantum yield of 78%. The fluorescence full width at half maximum（FHMW） of QDs is around 23 nm. The products are spherical with average size of 3-5 nm. There is a strong coordination effect between TGA and Cd2＋. Moreover, the results of interaction between as-made QDs and bovine serum albumin（BSA） suggest that the QDs-BSA binding reaction is a static quenching. The negative values of free energy（△G〈0） suggest that the binding process is spontaneous, △H〈0 and △S〈0 show that hydrogen bonds and van der Waals interactions play a major role in the binding reaction between QDs and BSA.

关键词： microwave synthesis Cd Te/TGA quantum dots bovine serum albumin interaction thermodynamics

Sm-Nd isotopic compositions of Cambrian-Ordovician strata at the Jinggangshan area in Jiangxi Province: Tectonic implications

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Chinese Science Bulletin 2009年第10期54卷 1750-1758页

作者： shen weizhou LING HongFei SHU LiangShu ZHANG FangRong XIANG Lei State Key Laboratory for Mineral Deposits Research College of Earth Sciences and Engineering Nanjing University Nanjing 210093China Geological Survey Institute Jiangxi Province Nanchang 330030 China

Whole-rock Sm-Nd isotopes were investigated for Cambrian-Ordovician strata from the Jinggangshan area between the Yangtze Block and Cathysia Block in South China. These strata were deposited as a greatly thick unit of muddy-sandy laminas with intercalated carbonate and organic carbon-bearing layers. They have low εNd(t) values of –13.9 to –7.9 and old Nd model ages of 1842 to 2375 Ma. In tDM-tStr diagram, they are far away from the concordant line but fall within the evolution zone of the Proterozoic crust of South China. This indicates that the Cambrian-Ordovician strata are mainly composed of mat- ters eroded from ancient Paleoproterozoic crust that may mainly consist of continental-derived detrital sediments with high maturity in the Cathysia Block. However, the Ordovician Jueshangou Formation and Dui’ershi Formation have εNd(t) values of –10.5 and –7.9 at the higher end of the above range and Nd model ages of 1842 to 2059 Ma at the lower end of the above range. This suggests involvement of more detritus that were eroded from the relatively juvenile crust from Late Paleoproterozoic to the Early Neoproterozoic. All the Nd model ages for the Cambrian-Ordovician sedimentary rocks in the Cathysia Block and the southeastern margin of the Yangtze Block are older than 1800 Ma, suggesting that no material from the Early Paleozoic depleted mantle-derived magmas was involved in these regions.

关键词： Nd同位素井冈山地区地层沉积奥陶系寒武系同位素组成构造意义 Sm

Petrogenesis of Mesozoic granitoids and volcanic rocks in South China： A response to tectonic evolution

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Episodes 2006年第1期29卷 26-33页

作者： Xinmin Zhou Tao Sun weizhou shen Liangshu Shu Yaoling Niu Department of Earth Sciences Nanjing University Nanjing 210093 China. Department of Earth Sciences Durham University Durham DHI 3LE UK.

This paper summarizes the new results on the petrogenesis of Mesozoic granitoids and volcanic rocks in South China. The authors propose that these rocks were formed in time and space as a response to regional tectonic regime change from the continent-continent collision of the Indosinian orogeny within the broad Tethyan orogenic domain in the Early Mesozoic （T1-T3）（Period Ⅰ） to the largely extensional setting as a result of the Yanshanian orogeny genetically associated with the NW-WNW-ward subduction of the paleo-Pacific oceanic lithosphere in the Late Mesozoic （J2-K2）（Period Ⅱ）. Of the Period I Indosinian granitoids, the early （T1-T2^1） ones are syn-collisional, and formed in a compressional setting; the late （T2^2-T3） ones are latecollisional, and formed in a locally extensional environment. During the Period Ⅱ Yanshanian magmatism, the Early Yanshanian （J2-J3） granitoid-volcanic rocks, which are distributed mainly in the Nanling Range and in the interior of the South China tectonic block （SCB）, are characteristic of rift-type intraplate magmatism, whereas the Late Yanshanian K1 granitoidovolcanic rocks are interpreted as genetically representing active continental margin magmatism. The K2 tholeiitic basalts interlayered with red beds are interpreted as genetically associated with the development of back-arc extensional basins in the interior of the SCB. The Yanshanian granitoid-volcanic rocks are distributed widely in South China, reflecting extensional tectonics within much of the SCB. The extension-induced deep crustal melting and underplating of mantle-derived basaltic melts are suggested as the two principal driving mechanisms for the Yanshanian granitic magmatism in South China.

关键词： SOUTHEASTERN CHINA CRUSTAL EVOLUTION JAPANESE ISLANDS GEOCHEMISTRY MAGMATISM ASIA ND CONSTRAINTS SUBDUCTION ACCRETION

Sm-Nd dating and Nd-Sr isotopic characteristics of the Shimian ophiolite suiten,Sichuan Province

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Chinese Science Bulletin 2002年第22期47卷 1897-1901页

作者： shen weizhou XU Shijin GAO Jianfeng YANG Zhusheng YANG Qiwen Department of Earth Sciences and State Key Laboratory of Mineral Deposit Research Nanjing UniversityNanjing 210093China Geological Survey Institute Panxi Geological TeamSichuan Bureau of Geology and Mineral Exploration and DevelopmentXichang 615000China

By mcasuring the Sm-Nd and Rb-Sr isotopiccompositions of harzburgite and gabbro from Shimianophiolite suite, we got the whole rock Sm-Nd isochron age of(938 ± 30) Ma (2σ), and the e Nd of 7.6 ± 0.8 (2σ), which showsthat the ophiolite was formed at the Early *** obvious change (0.70209-0.70708) of Isr values of theophiolite is caused by the meteoric hydrothermal *** high εNd values indicate that the primitive magma wasderived from the intense depleted mantle rescrvoir. It is sug-gested that this area was in a back-arc basin environmentduring the Early Neoproterozic.

关键词： Sm-Nd dating Nd-Sr isotopes ophiolite suite back-arc basin Shimian County Sichuan Province.

The thermal history of the miarolitic granite at Xincun, Fujian Province, China

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Chinese Science Bulletin 2000年第21期45卷 1991-1995页

作者： shen weizhou LING Hongfei LI Huimin LI Wuxian WANG Dezi State Key Laboratory for Mineral Deposits Research Department of Earth SciencesNanjing UniversityNanjing 210093China Tianjin Institute of Geology and Deposits the Ministry of Land and ResourcesTianjin 300170China Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China

The thermal history of the late Mesozoic miarolitic granite has been studied based on zircon U-Pb dating, whole rock Rb-Sr dating and K-Ar dating of muscovite, biotite and K-feldspar from the same rock sample. From the beginning of zircon crystallization to the closure of K-Ar system of biotite, the granite body had a slow cooling rate (11.0℃/Ma) and an ascending rate (0.07 mm/a). From the end of this stage to the closure of K-Ar system of K-feldspar, the granite body increased its cooling rate (45℃/Ma) and ascending rate (0.36 mm/a). The thermal history of the Xincun granite with a slow cooling rate at the early stage and a fast cooling rate at the late stage may have been related to the fact that the Fujian coastal area had very high geothermal gradient in the late Mesozoic and evident decrease in geothermal gradient in the early Cenozoic.

关键词： closure temperature thermal history paleothermal gradient Xincun miarolitic granite.

Petrogenesis of Early Cretaceous adakitic granodiorite: Implication for a crust thickening event within the Cathaysia Block, South China

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Science China Earth Sciences 2017年第7期60卷 1237-1255页

作者： SUN LiQiang LING HongFei ZHAO KuiDong CHEN PeiRong CHEN WeiFeng SUN Tao shen weizhou HUANG GuoLong State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University State Key Laboratory of Geological Processes and Mineral Resources and Collaborative Innovation Center for Exploration of Strategic Mineral Resources Faculty of Earth Resource China University of Geosciences Research Institute No.290 China National Nuclear Corporation

Adakitic rocks in continental settings are commonly considered to be formed by partial melting of thickened or delaminated lower crust. Investigations on this kind of rocks can provide important information about crustal evolution complementary to information from other rocks. This paper reports adakitic granodiorite of the Lingxi pluton in the interior of the Cathayisa Block. LA-ICP-MS zircon U-Pb dating shows that it was formed in the late Early Cretaceous(100±1 Ma). The granodiorite has geochemical features of adakitic rocks derived from partial melting of the thickened lower crust, e.g., high SiO2(mainly ranging from 64.4 to 68.9 wt.%) and Sr(624–894 ppm) contents, Sr/Y(49.9–60.8) and La/Yb(23.4–42.8) values, low Y(10.3–17.1 ppm), Ni(5.62–11.8 ppm) and MgO(mostly from 0.86 wt.% to 1.57 wt.%) contents and weak Eu anomaly. It has initial 87Sr/86 Sr ratios of 0.7086–0.7091, εNd(t) values of.6.2 to.5.9 and zircon εHf(t) values mostly of.10.1 to.7.6. Based on the geochemical characteristics and simple modelling, it is suggested that the most likely generation mechanism of the Lingxi granodiorite is partial melting of a thickened Proterozoic lower continental crust at a pressure ≥12 kbar(or crust thickness ≥40km), leaving a garnet-bearing amphibolite residue. Combining our results and previous studies of the tectonic evolution of the Cathaysia Block, we propose that the crust was thickened to over 40 km by a compressive event occurring during the late Early Cretaceous, which is supported by the observation that there is an angular unconformity between the Upper Cretaceous Series and the early Lower Cretaceous or the Jurassic rocks. After this event, the Cathaysia Block experienced a lithospheric extension and thinning probably driven by the high-angle paleo-Pacific subduction. With the attenuation of lithosphere, the lower crust was heated to partial melting by upwelling asthenospheric materials, resulting in generation of the Lingxi granodiorite and other coeval gran

关键词： Sr-Nd-Hf isotopes Adakitic rock Thickened crest Early Cretaceous South China

The Nd-Sr isotope study of Mesozoic granitoids in Jiangxi Province

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Chinese Science Bulletin 1999年第15期44卷 1427-1431页

作者： weizhou shen Hongfei Ling Wuxian Li Dezi Wang Xuan Huang Jun Pan Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

Nd-Sr isotopic compositions of 12 Mesozoic granitoids from Jiangxi Province have been reported. They show loe-εND（-13.8—- 8.3）, high-lsr（0.71069—0.73981） and old tDM （2087—1635 Ma）. Comparison between the Sm-Nd isotopic compositions of the granitoids and those of the basement metamorphic rocks suggests that these granitoids were mainly derived from the metasedimentary rocks. There is an east-west trend Mesozoic granitoid zone with lowtDM from S. Jiangxi to S. Fujian. The origin of these granites was preliminarily discussed.

关键词： Nd-Sr isotopic compositions material source low-tDM zone Mesozoic granitoids Jiangxi Province.

U-Pb dating of zircon grains from the ore-bearing plagioclase amphibolite in the Dashuigou Te deposit

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Chinese Science Bulletin 1998年第17期43卷 1486-1489页

作者： Shijin Xu weizhou shen Rucheng Wang Jianjun Lu Xiaoming Chen Yuping Lin Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China

The Dashuigou Te deposit is a unique independent one found in the world, and hosted in the plagioclase amphibolite. The upper intercept age of single zircon from the amphibolite can be considered to be the crystallization age of the source-rock of the amphibolite (tholeiitic basalt), while the lower intercept is nearly consistent with the time of the tectono-thermal event.

关键词： U-Pb dating single zircon grain plagioclase amphibolite Dashuigou Te deposit.

Classification and Source Materials of Continental Crust Transformation Series Granitoids in South China

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 287-298页

作者： Liu Changshi Zhu Jinchu shen weizhou Xu Shijin Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Jiang Minxi Department of Earth Sciences Nanjing University Nanjing Jiangsu

The granitoids of the continental crust transformation series in South China may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollision type. Based on the results of Sr and Nd isotopic determinations, the source material compositionof the three types of granitoids is calculated with crust-mantle binary mixing simulation. The calculations indi-cate that the granitoids of the first type consist of 78.6-89.7% upper crust endmember materials and15.0-10.3% depleted mantle endmember materials, the granitoids of the second type are composed of 63.7%upper crust endmember materials and 36.3% depleted mantle endmember materials, and those of the third type100% upper crust endmember materials. Hence. the source material composition of the granitoids of all thethree types is dominated by upper crust endmembers.

关键词： Classification and Source Materials of Continental Crust Transformation Series Granitoids in South China Source