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Science china Chemistry 2009年第8期52卷 1097-1103页

作者： li XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of Chemistry and Chemical Engineering,Graduate university of Chinese Academy of sciences,beijing 100049,china 1. college of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Synthesis of Conformationally LockedIsonucleosides: 2'-Deoxy-2'-nucleobase-5'-deoxy-1', 4' : 3' , 6'-dianhydro-D-mannitol

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Chemical Research in Chinese Universities 2001年第2期17卷 178-185页

作者： TIAN Xiao-bing, ZHANG ling, MIN Ji-mei and ZHANG li-he (School of Pharmaceutical sciences, beijing Medical university, beijing 100083, P. R. china) LU yang, JIANG Reng-wang and ZHENG Qi-tai (Institute of Materia Medica, peking Union Medical college &. Ch beijing Med Univ Sch Pharmaceut Sci Beijing 100083 Peoples R China peking Union Med Coll Inst Mat Med Beijing 100050 Peoples R China Chinese Acad Med Sci Beijing 100050 Peoples R China

Novel bicyclic isonucleosides, 2′-deoxy-2′ -nucleobase-5′-deoxy-1′ , 4′ : 3′ , 6′ -dianhydro- D-mannitol 10a-10c, were synthesized from D-glucose. The computer-assisted molecular simu- lation indicated that the... 详细信息

关键词： Bicyclic isonucleoside Locked conformation Synthesis

Apoptosis in Granulosa cells during follicular atresia: relationship with steroids and insulin-like growth factors

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Cell Research 2004年第4期14卷 341-346页

作者： Yuan Song YU, Hong Shu SUI, Zheng Bin HAN, Wei li, Ming Jiu LUO, Jing He TAN Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine, Shandong Agricultural university, Taian, Shandong 271018, china Present address: college of life science. university of beijing, beijing, china. 1Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine Shandong Agricultural University Taian Shandong 271018 China 1Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine Shandong Agricultural University Taian Shandong 271018 China 1Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine Shandong Agricultural University Taian Shandong 271018 China 1Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine Shandong Agricultural University Taian Shandong 271018 China 1Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine Shandong Agricultural University Taian Shandong 271018 China 1Laboratory of Animal Reproduction and Embryology college of Animal sciences and Veterinary Medicine Shandong Agricultural University Taian Shandong 271018 China

It is well known that during mammalian ovarian follicular development, the majority of follicles undergo atresia at various stages of their development. However, the mechanisms controlling this selection process remain unknown. In this study, we investigated apoptosis in granulosa cells during goat follicular atresia by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The changes in the levels of steroids, insulin-like growth factors (IGFs) and IGF receptors were studied by radioimmunoassay (RIA) and semi-quantitative reverse transcrip-tion-PCR. We found that the percentage of apoptotic granulosa cells in the atretic (A) follicles was significantly higher than that in the slightly atretic (SA) and healthy (H) follicles. The level of estradiol and the ratio of estradiol to progesterone in H follicles were significantly higher than those in A follicles. On the other hand, the level of progesterone was not significantly different among these follicle types. We also found that t

关键词： apoptosis ovarian follicle steroids IGFs atresia.

Measurement and simulation of the two-phase velocity correlation in sudden-expansion gas-particle flows

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Acta Mechanica Sinica 2011年第4期27卷 494-501页

作者： li-Xing Zhou.yang liu.Yi Xu Department of Engineering Mechanics,Tsinghua university,100084 beijing,china Marine Engineering college,Dalian Maritime university,116026 Dalian,china Department of Engineering Mechanics Tsinghua University Beijing China Marine Engineering college Dalian Maritime University Dalian China

In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer （PDPA） and simulated the system behavior by using both a Reynolds-averaged Navier-Stokes （RANS） model and a large-eddy simulation （LES）. The results of the measurements yield the axial and radial time-averaged velocities as well as the fluctuation velocities of gas and three particle-size groups （30μm, 50μm, and 95μm） and the gasparticle velocity correlation for 30μm and 50μm particles. From the measurements, theoretical analysis, and simulation, it is found that the two-phase velocity correlation of sudden-expansion flows, like that of jet flows, is less than the gas and particle Reynolds stresses. What distinguishes the two-phase velocity correlations of sudden-expansion flow from those of jet and channel flows is the absence of a clear relationship between the two-phase velocity correlation and particle size in sudden-expansion flows. The measurements, theoretical analysis, and numerical simulation all lead to the above-stated conclusions. Quantitatively, the results of the LES are better than those of the RANS model.

关键词： PDPA measurement - Simulation Two-phasevelocity correlation Sudden expansion gas-particle flows

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 1. Department of Chemical Engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology 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

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 chemistry, 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

New research progress on the ultrastructure of tectonically deformed coals

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Progress in Natural Science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,Xiaoshi li Laboratory of Computational Geodynamics,college of Earth Science,Graduate university of Chinese Academy of sciences,beijing 100049,china [a]Laboratory of Computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within china and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3) the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： Tectonically deformed coals Ultrastructure Pore structure Tectonic stress Strain environment

Up-conversion emissions of Er^(3+)-Yb^(3+) codoped Al_2O_3 nanoparticles by the arc discharge synthesis method

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DONG Bin1, CAO BaoSheng1, FENG ZhiQing1, WANG XingJun2, li ChengRen3 & HUA RuiNian4 1 School of Science, Dalian Nationalities university, Dalian 116600, china 2 School of Electronics Engineering and Computer Science, peking university, beijing 100871, china 3 college of Physics and Electronic Technology, liaoning Normal university, Dalian 116029, china 4 college of life Science, Dalian Nationalities university, Dalian 116600, china 1. School of Science Dalian Nationalities University Dalian 116600 China 2. School of Electronics Engineering and Computer Science Peking University Beijing 100871 China 3. college of Physics and Electronic Technology Liaoning Normal University Dalian 116029 China 4. college of life Science Dalian Nationalities University Dalian 116600 China

The Er3+-Yb3+ codoped Al2O3 nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 547 and 677 nm, corresponding respectively to the 2H11/2→4I15/2, 4S3/2→4I15/2 and 4 F9/2→4I15/2 transitions of Er3+, were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3Al5O12 and α-(Al,Er,Yb)2O3 phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4I11/2+a photon→4F7/2 and ET (III) of 2F5/2(Yb3+)+4I11/2(Er3+)→2F7/2(Yb3+)+4F7/2(Er3+) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3+-Yb3+ codoped Al2O3 arc discharge synthesis

Effects of Citral on Aspergillus flavus Spores by Quasi-elastic light Scattering and Multiplex Microanalysis Techniques

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 277-283页

作者： Man LUO1,2, li-Ke JIANG2, Yao-xiong HUANG3, Ming XIAO4, Bo li4, and Guo-lin ZOU1* 1college of life sciences, Wuhan university, Wuhan 430072, china 2college of life sciences, Anhui Agricultural university, Hefei 230036, china 3 Institute of Biomedical Engineering, Ji’nan university, Guangzhou 510632, china 4Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, the Institute of Biodiversity Science, Fudan university, Shanghai 200433, china college of life sciences Wuhan UniversityWuhan 430072 China college of life sciences Anhui Agricultural UniversityHefei 230036 China Institute of Biomedical Engineering Ji'nan UniversityGuangzhou 510632 China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering the Institute of Biodiversity Science Fudan UniversityShanghai 200433 China

Citral refined from litsea cubeba oil has been found to have a strong influence on fungi, especially Aspergillus flavus. Multiplex microanalysis and quasi-elastic light scattering techniques were applied to study the effects of citral on Aspergillus flavus spores from the levels of membrane, organelle and intracellular macromolecule. It was found that citral injured the wall and the membrane of A. flavus spore, resulting in decrease of its elasticity. After entering the cell, citral not only influenced the genetic expression of mitochondrion reduplication and its morphology, but also changed the aggregation of protein-like macromolecules. As a result, cells, organelles and macromolecules lost their normal structures and functions, eventually leading to the loss of germination ability of A. flavus spores. Since litsea cubeba oil as food additive and antifungal agent is safe and less poisonous, it is important to elucidate the inhibitory mechanisms of litsea cubeba oil on the germination ability of A. flavus spore.

关键词： citral Aspergillus flavus spore multiplex microanalysis techniques quasi-elastic light scattering technique

CHARACTERIZATION OF REGENERATED CELLULOSE MEMBRANES HYDROLYZED FROM CELLULOSE ACETATE

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Chinese Journal of Polymer Science 2002年第4期20卷 369-375页

作者： Yun Chen Xiao-peng xiong Guang yang li-na Zhang Sen-lin Lei Hui liang Electron Microscope Lab of Medical School, Wuhan university Wuhan 430072, china college of Chemistry and Molecular sciences, Wuhan university, Wuhan 430072, china Wuhan Univ Coll Chem & Mol Sci Wuhan 430072 Peoples R China Wuhan Univ Sch Med Electron Microscope Lab Wuhan 430072 Peoples R China

A series of cellulose acetate membranes were prepared by using formamide as additive, and then were hydrolyzed in 4 wt% aqueous NaOH solution for 8 h to obtain regenerated cellulose membranes. The dependence of degree of substitution, structure, porous properties, solubility and thermal stability on hydrolysis time was studied by chemical titration, Fourier transform infrared spectroscopy, scanning electron microscopy, wide-angle X-ray diffraction, and differential scanning calorimetry, respectively. The results indicated that the pore size of the regenerated cellulose membranes was slightly smaller than that of cellulose acetate membrane, while solvent-resistance, crystallinity and thermostability were significantly improved. This work provides a simple way to prepare the porous cellulose membranes, which not only kept the good pore characteristics of cellulose acetate membranes, but also possessed solvent-resistance, high crystallinity and thermostability. Therefore, the application range of cellulose acetate membranes can be expanded.

关键词： hydrolysis cellulose acetate thermal stability regenerated cellulose membrane pore size solvent-resistance SEM

Water distribution extracted from mining subsidence area using Kriging interpolation algorithm

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中国有色金属学会会刊：英文版 2011年第S3期21卷 723-726页

作者： DAI Hua-yang, REN li-yan, WANG Meng, XUE Hai-bing college of Geosicence and Surveying Engineering, china university of Mining & Technology, beijing 100083, china college of Geosicence and Surveying Engineering China University of Mining & Technology Beijing 100083 China

By comprehensively analyzing the data of geology and mining, Kriging algorithm was introduced to analyze the thematic information of geological data, to rapidly extract mining parameters for predicting mining subsidence, and to effectively integrate geomorphology and predict information. As a result, the change information of water body is successfully detected from the prediction of surface subsidence due to mining activity. Analysis shows that the elevation of farmland in the west side of water body will be lower than ever, and the west part farmland will be submerged. However, there is no evidence for impacting the villages. All the information provides a reference for efficiently assessing environmental impact due to mining activity, which can help to govern the subsidence of the area reasonably.

关键词： Kriging interpolation water body mining subsidence prediction parameters data fusion