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Preparation and microstructure of CuO-CoO-MnO/SiO2.nanocomposite aerogels and xerogels as catalyst carriers

Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2.Xi-zhe ZHAO~3,Qian-yi JIA~4.Hong-sheng LI~4.1.College of Light Industry,hebei United university,{2. 063000,{4. 2.College of Chemical Engineering,hebei United university,{2. 063.09,{4. 3.College of Printing and Packaging Engineering,Beijing Institute of Graphic Communication,Beijing 102.00,{4. 4.College of Materials Science and Engineering,hebei United university,{2. 063.09,{4. College of Light Industry Hebei United University Tangshan 063000 China College of Chemical Engineering Hebei United University Tangshan 063009 China College of Printing and Packaging Engineering Beijing Institute of Graphic Communication Beijing 102600 China College of Materials Science and Engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2.anocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2.upercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2.anocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2.anocomposite aerogels are porous,with a pore size distribution of 2.50 nm,an average pore size of 19.4.nm,a specific surface area of 384.9 m2.g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2.omposite xerogels is 1.7-12..6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2.g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2.anocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

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Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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Science china Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3, QU Jing1 & ZHAO Wenxia4.1. Graduate School, china university of Geosciences, Wuhan 4.0074. china 2. Test Center, china university of Geosciences, Wuhan 4.0074. china 3. Physics and Technology College, Wuhan university, Wuhan 4.0072. china 4. Test Center, Zhongshan university, Guangzhou 5102.5, china Graduate School China University of Geosciences Wuhan 430074 China Test Center China University of Geosciences Wuhan 430074 China Physics and Technology College Wuhan University Wuhan 430072 China Test Center Zhongshan University Guangzhou 510275 China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.4.3 nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3m and Fd3m, respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974. is F4.32. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

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Automorphisms with order three of affine Lie algebras

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Chinese Science Bulletin 1998年第21期43卷 1793-1798页

作者： JIN Quanqin 1,2.and HOU Zixin 2.1. Department of Mathematics, hebei university, Baoding 071002.{2. 2. Department of Mathematics, Nankai university, Tianjin 300071,{2. Department of Mathematics Hebei University Baoding China Department of Mathematics Nankai University Tianjin China

Some properties of automorphisms of affine Lie algebras are presented. Automorphisms with order three are classified up to conjugacy, and their fixed point sets are also computed. As a corollary, it is proved that two... 详细信息

关键词： affine Lie algebra automorphism of order three first (second) kind of automorphism.

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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4.1. Institute of Physics, College of Chemical Engineering, Sichuan university, Chengdu 610065, china 2. Institute of Theoretical Physics, Xihua Normal university, Nanchong 637002. china 3. Department of Physics, china Oceanography university, Qingdao 2.6003, china 4. College of Physics, Sichuan university, Chengdu 610065, china Institute of Physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China College of Physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2. LU Yuanzheng1,2.3 & XU Daoyi4.1. Research Institute of Petroleum Exploration and Development, Beijing 100083, china 2. Key Laboratory of Oil and Gas Reservoir of Petro{4., Beijing 100083, china 3. china university of Geosciences, Beijing 100083, china 4. Institute of Geology, china Earthquake Administration, Beijing 10002., china Research Institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china university of Geosciences Beijing China Institute of Geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science china Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2.& GAO Bangfei1,2.1. State Key Laboratory of Geological Processes and Mineral Resources,{4. university of Geosciences, Beijing 100083,{4. 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education,{4. university of Geo- sciences, Beijing 100083,{4. 3. Faculty of Earth Sciences,{4. university of Geosciences, Wuhan 4.0074.{4. 4. School of Mathematics and Information Science, Guangzhou university, Guangzhou 5104.5,{4. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China School of Mathematics and Information Science Guangzhou University Guangzhou China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

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Fluvastatin inhibits activation of JAK and STAT proteins in diabetic rat glomeruli and mesangial cells under high glucose conditions

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Acta Pharmacologica Sinica 2007年第12期28卷 1938-1946页

作者： Yong-hong SHI~2.Song ZHAO~2.Chen WANG~2.Ying LI~3,Hui-jun DUAN~(2.4.~2.Department of Pathology,hebei Medical university,Shijiazhuang 050017 ~3 Institute of Nephrology,Third Hospital,hebei Medical university,Shijiazhuang 050051,china Department of Pathology Hebei Medical University Shijiazhuang China Institute of Nephrology Third Hospital Hebei Medical University Shijiazhuang China

Aim:The aim of the present study was to further elucidate the mechanism of theprotective role of fluvastatin on diabetic ***:Streptozotocin-induced diabetic rats were treated daily with fluvastatin (4.mg/kg body weight) *** animals were killed 4.weeks later and urine and blood samples *** kidney tissues were removed and subjected to the *** glomerular mesangial cells (GMC) were cultured under normalglucose (5.5 mmol/L),high glucose (HG,30 mmol/L),HG+AG4.0 (10 μmol/L),orHG with fluvastatin (1 μmol/L).Glomeruli or the GMC lysate was immunoprecipi-tared and/or immunoblotted with antibodies against Janus kinase 2.(JAK2.,SH2.domain containing tyrosine phosphatase-1 (SHP-1),phosphospecific SHP-2.andsignal transducer and activators of transcription (STAT),***-forming growth factor-β(TGF-β1) mRNA was measured by *** proteinsynthesis of TGF-β1 and fibronectin in the culture medium of GMC was detectedby ***:The phosphorylation levels of JAK2.STAT1,STAT3,andSHP-2.increased significantly,and SHP-1 phosphorylation was reduced in glom-eruli of diabetic *** with fluvastatin reduced phosphorylation levelsof JAK2.STAT1,STAT3,and SHP-2.in glomeruli of diabetic rats,but it had noeffect on the dephosphorylation of *** exposure of GMC to 30 mmol/Lglucose caused the activation of JAK2.STAT1,STAT3,and *** upregulatedTGF-β1 expression and increased protein synthesis of *** highglucose-induced changes were suppressed by fluvastatin,as well as AG4.0,aJAK2.***:The regulation of the phosphorylation of JAK/STATby fluvastatin may be responsible for its renal protective effects on diabeticnephropathy.

关键词： fluvastatin diabetic nephropathy Janus kinase signal transducer and activators of transcription

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Experimental study of ore gabbro liquid immiscibility

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Science china Earth Sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2. XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4.1. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., china 2. Wuhan university, Wuhan 4.0072. china 3. Institute of Geology, china Seismological Bureau, Beijing 10002., china 4. Faculty of Earth Sciences, china university of Geosciences, Wuhan 4.0074. china Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Wuhan university Wuhan China Institute of Geology China Seismological Bureau Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 12.0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

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Quantitative analysis on soil erosion based on 3S technology

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中国有色金属学会会刊：英文版 2005年第S1期15卷 82-85页

作者： JING Hai-tao~1, XIE Hong-quan~(2. 3), FU Mei-chen~2. FENG Zhong-ke~4.(1. Xuzhou Normal university, Xuzhou 2.1009,{4. 2.{4. university of Mining and Technology(Beijing Campus), Beijing 100083,{4. 3. hebei Polytechnic university, tangshan 063.09,{4. 4. Beijing Forestry university, Beijing 100083,{4. Xuzhou Normal Univ Xuzhou 221009 Peoples R China china Univ Min & Technol Beijing 100083 Peoples R China hebei Polytech Univ Tangshan 063009 Peoples R China Beijing Forestry Univ Beijing 100083 Peoples R China

The quantitative analysis on soil erosion is very significant for macro-decision of soil loss, for quick control of natural disasters and for system of periodical report. Based on the research of 3S(GPS, GIS and RS), the special information can be obtained by GPS or RS. Digital elevation model can be formed by GIS software, and at the same time, we can get some vector graph, such as landuse, vegetation type and soil type. Then the soil erosion of research area was calculated by USLE. The methods and techniques were discussed, including how to carve up polygons, how to capture the values of factors and how to differentiate the erosion intensity.

关键词： soil erosion USLE GPS GIS RS

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Urotensin Ⅱ accelerates cardiac fibrosis and hypertrophy of rats induced by isoproterenol

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Acta Pharmacologica Sinica 2007年第1期28卷 36-43页

作者： Yong-gang ZHANG~(2.5) Yu-guang LI~2.Bao-guo LIU~3 Rui-hong WEI~2.Dong-ming WANG~2.Xue-rui TAN~2.Ding-fang BU~4.Yong-zheng PANG~4.Chao-shu TANG~4.0}Department of Cardiovascular Diseases,First Affiliated Hospital,Shantou university Medical College,Shantou 51504.,china 3 The Affiliated Hospital,Medical School of {2. university of Engineering,{2. 05602.,china,4.Institute of Cardiovascular Research,Peking university First Hospital,Beijing 100034.china Department of Cardiovascular Diseases First Affiliated Hospital Shantou University Medical College Shantou China The Affiliated Hospital Medical School of Hebei University of Engineering Hebei China Institute of Cardiovascular Research Peking University First Hospital Beijing China

Aim:To study whether urotensin II（UII）,a potent vasoconstrictive peptide,isinvolved in the development of cardiac hypertrophy and fibrogenesis of ratsinduced by isoproterenol（ISO）.Methods:Thirty male Wistar rats were randomlydivided into 3 *** 1 was the healthy control group,group 2.was the ISOgroup,and group 3 was the ISO+UII *** groups 2.and 3,ISO(5 mg-kg-1.d-1)wasgiven（sc）once daily for 7 *** 3 was also given UII in the first day [3 nmol/kg（5μg/kg）,iv],followed by sc（1.5 μg/kg）twice *** 1 received 0.9% *** receptor（UT）mRNA expression was determined by *** contents ofUII and angiotensin II（Ang II）were determined by *** vitro,the effects of UII on DNA/collagen synthesis of cardiac fibroblasts were deter-mined by [3H]thymidine/[3H]proline ***:The ratio of heartweight/body weight,plasma lactate dehydrogenase activity,myocardialmalondialdehyde and hydroxyproline concentration increased significantly in theISO group,as well as UT mRNA expression,plasma and cardiac UII and ventricu-lar Ang II,compared with the control group（P<0.01）.ISO induced significantmyocardial ***,UII+ISO co-treatment significantly increasedthe changes of biochemical markers of injury and the degree of cardiac hypertro-phy and *** vitro,5×10～9-5×10-7mol/L UII stimulated[3H]thymidine/[3H]proline incorporation into cardiac fibroblasts in a dose-dependent manner（P<0.01）.Conclusion:These results suggest that UII was involved in the development ofcardiac fibrosis and hypertrophy by synergistic effects with ISO.

关键词： cardiac remodeling cardiac fibrosis GPR14.receptor urotensin II collagen

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