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Investigation of solvatochromism and aggregation behavior of C_(60)(C_4H_(1.)N^+)I^- in binary solvent mixtures

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Chinese science Bulletin 2003年第18期48卷 1938-1942页

作者： WANG Guanwu1. HAO Erhong1. JIAO Lijuan1.& YAN Lifeng2 1. Department of Chemistry, university of {1. and Technology ofchina,{3., china 2. Department of Chemical physics, university of {1. and Technol-ogy of china,{3., china Correspondence should be addressed to Wang Guanwu (e-mail: gwang @***) Department of Chemistry University of Science and Technology of China Helei 230026 China

Water-soluble N,N-dimethyl[60]fulleropyrro-lidinium iodide (C60(C4H1.N+)I-), when dissolved in binarymixtures of tetrahydrofuran and water, was found to exhibit remarkable solvatochromism. Correspondingly, the UV-vis spectra showed obvious changes by variation of the solventcomposition of tetrahydrofuran and water. It was found that both concentration and temperature had strong influence on the stability of monomer-state C60(C4H1.N+)I-, while theyhad little effect on the stability of aggregated C60(C4H1.N+) I-The formation of cluster was confirmed by TEM and AFMmeasurements.

关键词： N N-dimethylfulleropyrrolidinium iodide solvato-chromism aggregation.

Topological chirality and achirality of the closed circular DNAs

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Chinese science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. Department of Chemical physics, {1. of science and Technology of{3., hefei 230026,{3. 2. Department of Chemistry, Lanzhou {1., Lanzhou 73.000,{3. Depaitment of Chemical physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life {1.. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.

DIRECT NUMERICAL SIMULATIONS OF TURBULENT CHANNEL FLOWS WITH CONSIDERATION OF THE BUOYANCY EFFECT OF THE BUBBLE PHASE

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Journal of Hydrodynamics 2011年第3期23卷 282-288页

作者： LIU Nan-sheng CHENG Bao-guo QUE Xia LU Xi-yun Department of Modem Mechanics University of Science and Technology of China Hefei 230026 China Department of Computer science and Technology Hefei University of Technology Hefei 230009 China

Turbulent channel flows with consideration of the buoyancy effect of the bubble phase is investigated by means of the Direct Numerical Simulation （DNS）. This two-phase system is solved by a two-way coupling Lagrangian-Eulerian approach. The Reynolds number based on the friction velocity and the half-width of the channel is 1.4, and the gravitational acceleration varies from -0.5 to 0.5, ranging from the upflow to the downflow cases. This study aims to reveal the influence of buoyancy on the turbulence behavior and the bubble motion. Some typical statistical quantities, including the averaged velocities and velocity fluctuations for the fluid and bubble phases, as well as the flow structures of the turbulence fluctuations, are analyzed.

关键词： Direct Numerical Simulations (DNS) turbulent bubbly flow upflow/downflow turbulence fluctuations bubble statistics turbulence structures

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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science{1. Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1.2) & GUO Maozheng~(1.3. 1. School of Mathematical {1.s,Peking university,Beijing 1.0871.china 2. Department of Mathematics,Yantai university,Yantai 264005,china 3. LMAM,Peking university,Beijing 1.0871.china 1. School of Mathematical sciences Peking University 100871 Beijing China 2. Department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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science{1. Earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1.2, MEI Bowen1.& CAO Yacheng3.1. Jianghan Petroleum {1., Jingzhou 43.1.0, china 2. Huazhong {1. of {3. and Technology, Wuhan 43.047, china 3. Nanjing Institute of Soil {3., Chinese Academy of {3.s, Nanjing 21.008, china 1. Jianghan Petroleum university 434100 Jingzhou China 2. Huazhong university of {1. and Technology 430047 Wuhan China 3. Nanjing Institute of Soil {1. Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 1.N is in the range of ?6‰-20‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 1.N with the value of about 1.-5‰ whereas the oils in saline or semi-saline environment have higher δ 1.N, with most samples being above 1.‰ and some exceeding 1.‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 1.N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 1.N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1. Liu Chong2, Lian Linsheng3. Zhao Chunjiang1. Bao Haigang1.and Wu Changxin1.1. College of Animal {1. and Technology, china Agricultural university, Beijing 1.0094, china 2. College of Biological {1., china Agricultural university, Beijing 1.0094, china 3. College of Animal {1. and Technology, Yunnan Agricultural university, Kunming 650201. china) College of Animal science and Technology China Agricultural University Beijing 100094 China College of Biological science China Agricultural University Beijing 100094 China College of Animal science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

Chinese Jingdezhen blue and white imperial porcelain

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science{1.(Technological sciences) 2004年第3期47卷 366-375页

作者： WU Juan1. LI Jiazhi1. DENG Zequn1.& WANG Changsui2 1. Laboratory of Ancient Ceramics, Shanghai Institute of Ceramics, Chinese Academy of sciences, Shanghai 200050,{1. 2. Department of History of science and Archaeometry, {3. of science and Technology of{1., hefei 230026,{1. Chinese Acad Sci Shanghai Inst Ceram Lab Ancient Ceram Shanghai 200050 Peoples R China Univ Sci & Technol china Dept Hist Sci Archaeometry Hefei 230026 Peoples R China

Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.

关键词： energy dispersive X-ray fluorescence analysis, blue and white imperial porcelain, correspondence analysis.

Electron surfing acceleration in a current sheet of flares

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science{1.(physics,Mechanics & Astronomy) 2009年第11期52卷 1810-1812页

作者： WANG DeYu1.& LU QuanMing2 1.Purple Mountain Observatory, Nanjing 21.008, china 2 School of Earth and Space {1.s, university of {1. and Technology of china, hefei 230026, china Purple Mountain Observatory Nanjing 210008 China School of Earth and Space sciences University of Science and Technology of China Hefei 230026 China

A model of electron acceleration in a current sheet of flares is studied by the analytical approximation solution and the test particle simulation. The electron can be trapped in a potential of propagating electrostatic wave. The trapped electron moving with the phase velocity v p of wave may be effectively accelerated by ev p/c × B z force along the outflow direction in the current sheet, if a criterion condition K > 0 for electron surfing acceleration is satisfied. The electron will be accelerated continuously until the electron de-trap from the wave potential at the turning point S.

关键词： electron acceleration electrostatic wave current sheet

Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest china:Evidence from sandstone detrital and geochemical records

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science{1. Earth sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1. GUO Hong2, WANG Daoxuan3.& LIN Wei1.1. Institute of Geology and Geo{1., Chinese Academy of sciences, Beijing 1.0029, china 2. Tarim Oilfield Branch, CNPC, Korla 841.00, china 3. hefei university of Industry, Tunxilu 1.3. hefei 23.009, china 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing Chin 2. Tarim Oilfield Branch CNPC 841000 Korla China 3. {1. university of Industry Tunxilu 193 230009 Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest china, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1. From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2) For major element geo- chemical parameters of whole sandstones, CaO and Fe2 O * {1.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. ({1. Contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2O{1.(CaO+Na2O) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-Cenozoic.