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Acta Pharmacologica Sinica 2007年第12期28卷 1914-1918页

作者： Yan TAN~(2,3,5),Qiang TANG~4,Ben-rong HU~4,Ji-zhou XIANG~4~2 Institute of Urology,Renmin Hospital,Yunyang Medical College,Shiyan 442000 china,~3 Department of Pharmacology,Yunyang MedicalCollege,Shiyan 442000,china,~4 Department of Pharmacology,Tongji Medical College,Huazhong University of Science and Teehnology,Wuhan 430030,china Institute of Urology Renmin HospitalYunyang Medical CollegeShiyan 442000China Department of Pharmacology Yunyang Medical CollegeShiyan 442000China Department of Pharmacology Tongji Medical CollegeHuazhong University of Science and TechnologyWu

Aim:To investigate the antioxidant properties of berberine (Ber) on corpuscavenosum smooth muscle cells (CCSMC) in penile erectile ***:We examined the effects of Ber on cultured rabbit CCSMC damaged by hydrogenperoxide (H2O2) through examining cell viability by methyl thiazolyl tetrazoliumassay and assessing the level of malondialdehyde (MDA),superoxide dismutase,(SOD) activity,nitric oxide (NO) products,and lactate dehydrogenase (LDH) re-lease in cells after stimulation with ***:Treatment with 1 mmol/L H2O2significantly decreased the cell viability,NO products,and SOD activity of CCSMCfrom 100% to 48.57%±4.1% (P49.5±1.8 to 30.1±2.6 U/mL (P497.6±69.5 to 1100.5±56.3 U/L (P4±2.9nmol/mg protein (P<0.01),***,treatment with different con-centrations of Ber (10-1000 μmol/L) inhibited the damaging effects of H2O2,withincreased cell viability (P<0.05 or P<0.01),NO production (P<0.01),and SODactivity (P<0.01) and decreased LDH release and MDA content (both P<0.01).Conclusion:Bet could produce its antioxidant action on oxidative stress-inducedcultured *** effects may be of benefit in the prevention of penileerectile dysfunction.

关键词： berberine antioxidant action corpus cavernosum erectile dysfunction

Long-term variation time scales in OJ 287

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Research in Astronomy and Astrophysics 2010年第11期10卷 1100-1108页

作者： Jun-Hui Fan Yi Liu Bo-Chun Qian Jun Tao Zhi-Qiang Shen Jiang-Shui Zhang Yong Huang Jin Wang Center for Astrophysics Guangzhou University Guangzhou 510400 China Astronomy Science and Technology Research Laboratory. of Department of Education of Guangdong Province Guangzhou 510006 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology ShAO and USTC Chinese Academy of Sciences China

The light curve data from 1894 to 2008 are compiled for the BL Lacertae object OJ 287 from the available literature. Periodicity analysis methods （the Discrete Correlation Function-DCF, the Jurkevich method, the power spectral （Fourier） analysis, and the CLEANest method） are performed to search for possible periodicites in the light curve of OJ 287. Significance levels are given for the possible periods. The analysis results confirm the existence of the 12.2 ± 0.6 yr time scale and show a hint of a -53 yr time scale. The 12.2 ± 0.6 yr period is used as the orbital period to investigate the supermassive binary black hole system parameters.

关键词： galaxies active -- galaxies: general-- methods: data analysis -- galax- ies individual (OJ 287)

Temporal variation of suspended sediment load in the Pearl River due to human activities

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International Journal of Sediment Research 2011年第4期26卷 487-497页

作者： Wei ZHANG,Shousheng MU,Yanjing ZHANG,and Kaimin CHEN 1 Assoc.Prof.,State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University, Nanjing,210098,china, 2,4 Graduate student,College of Harbor,Coastal and Offshore Engineering,Hohai University,Nanjing,210098, china 3 Prof.,china Institute of Water Resources and Hydropower Research,Beijing,100038,china [a] Assoc. Prof. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China [b] Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China [c] Prof. China Institute of Water Resources and Hydropower Research Beijing 100038 China [d] Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

Data on sediment flux at three hydrologic stations from the 1950s to 2006 are utilized to study the decadal,annual,and monthly variations in suspended sediment load delivered from the Pearl River to the *** show that variations in sediment flux from three main tributaries,including the West River,the North River and the East River,are spatially *** nearly 90%of the suspended sediment load comes from the West River,its variation has dominated the overall tendency of sediment flux in the entire Pearl *** a significant decreasing trend exists in the annual variation of the total sediment flux,the decadal change can be divided into an increasing phase and a decreasing phase,with the turning point between the two phases in the late *** the 1950s to the 1980s,the average annual river sediment flux increased by 30.43%.However,sediment flux has decreased significantly since the 1990s,with the average sediment flux being 38.60%less in the 2000s than that in the *** current sediment flux is also 52.93%less than its peak in the 1980s. The monthly variation pattern of the suspended sediment load transport to the sea is more interesting. For the West River,all months show a decreasing trend,and for most months the reduction values are ***,for the East River the sediment load shows a decrease trend in the dry season and an increase trend in the wet *** method of regression analysis was used to study the influence of precipitation in the variation on the sediment *** was found that the climate change is not the main driving force behind the variation in suspended sediment *** the 1990s, intensive land use destroyed the vulnerable ecosystem of the upper Pearl River,and speeded up the process of rocky ***,aggravated soil erosion caused an increase in suspended sediment ***,sediment retention within reservoirs had begun to play a dominant role after the massive constru

关键词： Pearl River Sediment flux Human activities Rocky desertification Dam construction

Preparation of grain size controlled boron-doped diamond thin films and their applications in selective detection of glucose in basic solutions

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Science china Chemistry 2010年第6期53卷 1378-1384页

作者： ZHAO JianWen1,2,WANG JinLiang3,ZHI JinFang3 & ZHANG ZhiMing4 1College of Chemistry and Chemical Engineering,Jishou University,Jishou 416000,china 2Schools of Materials Science and Engineering,Nanyang Technological University,639798,Singapore 3Laboratory of Organic Optoelectronic Functional Materials and Molecular Engineering,Technical Institute of Physics and Chemistry & Graduate University of Chinese Academy of Sciences,Beijing 100080,china 4Research Institute of Micro-Nano Science and Technology,Shanghai Jiao Tong University,Shanghai 200030,china 1. College of Chemistry and Chemical Engineering Jishou University Jishou 416000 China2. Schools of Materials Science and Engineering Nanyang Technological University 639798 Singapore Singapore3. Laboratory of Organic Optoelectronic Functional Materials and Molecular Engineering Technical Institute of Physics and Chemistry & Graduate University of Chinese Academy of Sciences Beijing 100080 China4. Research Institute of Micro-Nano Science and Technology Shanghai Jiao Tong University Shanghai 200030 China

Boron-doped diamond (BDD) thin films with different crystal grain sizes were prepared by controlling the reacting gas pressure using hot filament chemical vapor deposition (HFCVD).The morphologies and structures of the prepared diamond thin films were characterized by scanning electron microscopy (SEM) and Raman *** electrochemical responses of K4Fe(CN)6 on different BDD electrodes were *** results suggested that electron transfer was faster at the boron-doped nanocrystalline diamond (BDND) thin film electrodes in comparison with that at other BDD thin film *** prepared BDD thin film electrodes without any modification were used to directly detect glucose in the basic *** results showed that the as-prepared BDD thin film electrodes exhibited good selectivity for detecting glucose in the presence of ascorbic acid (AA) and uric acid (UA).The higher sensitivity was observed on the BDND thin film grown on the boron-doped microcrystalline diamond (BDMD) thin film surface,and the linear response range,sensitivity and the low detection limit were 0.25–10 mM,189.1 μA mmol-1 cm-2 and 25 μM (S/N=3) for glucose in the presence of AA and UA,respectively.

关键词： diamond thin films electrochemical properties selective glucose detection

Sediment pollution and its effect on fish through food chain in the Yangtze River

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International Journal of Sediment Research 2008年第4期23卷 338-347页

Suspended sediment adsorbs pollutants from flowing water in rivers and deposits onto the bed. However, the pollutants accumulated in the river bed sediment may affect the bio-community through food chain for a long period of time. To study the problem the concentration of heavy metals (Cr, Cd, Hg, Cu, Fe, Zn, Pb and As) in water, sediment, and fish/invertebrate were investigated in the middle and lower reaches of the Yangtze River during 2006-2007. The concentrations of heavy metals were 100-10,000 times higher in the sediment than in the water. Benthic invertebrates had relatively high concentrations of heavy metals in their tissues due to their proximity to contaminated sediments. Benthic invertivore fish had moderately high concentrations of heavy metals whereas phytoplanktivore fish, such as the silver carp, accumulated the lowest concentration of heavy metals. The concentrations of Cu, Zn, and Fe were higher than Hg, Pb, Cd, Cr, and As in the tissue samples. The concentration of heavy metals was lower in the river sediments than in the lake sediments. Conversely, the concentration of heavy metals was higher in river water than in lake water. While a pollution event into a water body is often transitory, the effects of the pollutants may be long-lived due to their tendency to be absorbed in the sediments and then released into the food chain. The heavy metals were concentrated in the following order: bottom material > demersal fish and benthic fauna > middle-lower layer fish > upper-middle layer fish > water.

关键词： Sediment pollution Heavy metal Fish Invertebrate Yangtze River

Propagation of liquid surface waves over finite graphene structured arrays of cylinders

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Theoretical & Applied Mechanics Letters 2011年第5期1卷 73-76页

作者： Xuemei Liu,1,2 Yong Wei,1 Sheng Li,1 Yousheng Xu,1,Detang Lu,3 and Boming Yu 4 1) Department of Physics,Zhejiang Normal University,Jinhua 321004,Zhejiang,china 2) Hangzhou No.14 Middle School,Hangzhou 310006,china 3) Department of Modern Mechanics,University of Science and Technology of china,Hefei 230027,china 4) School of Physics,Huazhong University of Science and Technology,Wuahn 430074,china School of Physics Huazhong University of Science and Technology Wuahn 430074 China

Based on the multiple scattering method,this paper investigates a benchmark problem of the propagation of liquid surface waves over finite graphene (or honeycomb) structured arrays of *** the graphene structured array with the square structured and with triangle structured arrays,it finds that the finite graphene structure can produce more complete band gaps than the other finite structures,and the finite graphene structure has less localized ability than the other finite structures.

关键词： propagation liquid surface wave graphene structured array multiple scattering method

Preparation of microencapsulatedα-olefin drag reducing polymer used in oil pipeline transportation

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Petroleum Science 2011年第1期8卷 99-107页

作者： Li Bing Xing Wenguo Dong Guilin Chen Xiangjun Zhou Ningning Qin Zhanbo Zhang Changqiao School of Chemistry and Chemical Engineering Shandong UniversityShandong 250061China Linyi Institute of Product Quality Supervision and Inspection Shandong 276004China Shandong Institute of Metrology Shandong 250014China Shandong Quality Certification Centre Shandong 250014China

Microcapsules containing oil drag-reducing polymer particles were prepared by melting-scattering and condensing of polyethylene wax,in-situ polymerization of urea and formaldehyde,and interfacial polymerization of styrene *** related processes were studied by a molecular dynamics simulation method,and molecular design of microcapsule isolation agent was carried out on the basis of the *** technologies for preparing microencapsulated oil drag-reducing polymer particles were compared and the circulation drag reducing efficiency of the microencapsulated polymer particles was evaluated based on the characterization results and their dissolution *** design of a microcapsule isolation agent suggests that a-olefin polymer particles can be stably dispersed in water by using long-chain alkyl sodium salt surfactant which can prevent the agglomeration ofα-olefin polymer *** results of simulation of the adsorption process shows that the amount of alkyl sodium salt surfactant can directly affect the stability of microencapsulatedα-olefin polymer particles, and there must be a minimum critical amount of *** characterization of the morphology by Scanning Electron Microscopy（SEM） and comparison of the static pressure stability,especially the conditions of reaction and technological control of microcapsules with different shell materials,microencapsulation of a-olefin polymer particles with poly-（urea-formaldehyde） as shell material was selected as the optimum scheme,because it can react under mild conditions and its technological process can be controlled in a large *** relationship of drag reducing rate and dissolving time of microcapsules showed that the formation of microcapsules did not affect the maximum drag reducing rate,and the drag reducing rate of each sample can reach about 35%along with the dissolving time,*** did not affect the drag reducing property ofα-olefin polymer.

关键词： α-olefin polymer molecular design coating material microcapsule preparation stability and solubility drag reducing property

Analysis of Earthquake-Triggered Failure Mechanisms of Slopes and Sliding Surfaces

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Journal of Mountain Science 2010年第3期7卷 282-290页

作者： WANG Jian YAO Lingkan Arshad Hussain School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China MOE Key Laboratory of High-speed Railway Engineering Southwest Jiaotong University Chengdu 610031 China Road and Railway Engineering Research Institute Sichuan Key Laboratory of Aseismic Engineering and Technology Chengdu 610031 China National University of Sciences and Technology (NUST) Islamabad 44000 Pakistan

Earthquake-induced landslides along the Dujiangyan-Yingxiu highway after the Ms 8.0 Wenchuan earthquake in 2008 were investigated. It was found that：（1） slopes were shattered and damaged during the earthquake and open tension cracks formed on the tops of the slopes; （2） the upper parts of slopes collapsed and slid, while the lower parts remained basically intact, indicating that the upper parts of slopes would be damaged more heavily than the lower parts during an earthquake. Large-scale shaking table model tests were conducted to study failure behavior of slopes under the Wenchuan seismic wave, which reproduced the process of deformation and failure of slopes. Tension cracks emerged at the top and upper part of model, while the bottom of the model remained intact, consistent with field investigations. Depth of the tension crack at the top of model is 32 cm, i.e., 3.2 m compared to the prototype natural slope with a height of 14 m when the length scale ratio （proto/model） is lo. Acceleration at the top of the slope was almost twice as large as that at the toe when the measured accelerations on shaking table are 4.85 m/s2 and 6.49 m/s2, which means that seismic force at the top of the slope is twice the magnitude of that at the toe. By use of the dynamic-strength-reduction method, numerical simulation was conducted to explore the process and mechanism of formation of the sliding surface, with other quantified information. The earthquake-induced failure surfaces commonly consist of tension cracks and shear zones. Within 5 mfrom the top of the slope, the dynamic sliding surface will be about 1 m shallower than the pseudo-static sliding surface in a horizontal direction when the peak ground acceleration （PGA） is 1 m/s2; the dynamic sliding surface will be about 2 m deeper than the pseudo-static sliding surface in a horizontal direction when the PGA is lo m/sL and the depths of the dynamic sliding surface and the pseudo-static sliding surface will be almost the sam

关键词： Subgrade engineering slope failuremechanism shaking table model test: seismicsliding surface Wenchuan earthquake

Dynamics of risers for earthquake resistant designs

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Petroleum Science 2010年第2期7卷 273-282页

作者： Duan Menglan Wang Yi Yue Zhiyong Estefen Segen Yang Xiaogang School of Naval Architecture and Marine Engineering Dalian University of Technology Dalian Liaoning 116024 China Offshore Oil/Gas Research Center China University of Petroleum Beijing 102249 China Department of Mechanics and Engineering Peking University Beijing 100080 China COPPE Federal University of Rio de Janeiro EO.Box 68508 RJ 21945-970 Brazil Design Division CNOOC Engineering Tanggu Tianjin 300452 China

It is well known that no criterion about seismic design for risers is available, and relevant research has not been reported. A comprehensive study of riser dynamics during earthquakes is performed in this paper. A dynamic model for seismic analysis of risers is developed in accordance with the working environment of the risers and the influence of inertia force of the pipelines. The dynamic equations for the developed model are derived and resolved on the basis of the energy theory of beams. Numerical simulation for an engineering project in the Bohai Oil Field, china shows that the fundamental frequency of the riser plays the major role in the seismic responses, and for platforms in shallow water in Bohai Bay, the risers demonstrate a much lower stress response due to prominent differences between the riser frequency and the earthquake wave frequency. The presented model and its corresponding method for seismic analysis are practical and important for riser design resistant to earthquake waves.

关键词： Subsea pipeline riser seismic design dynamic response earthquake wave Hamilton theory

Preconditioners for higher order edge finite element discretizations of Maxwell's equations

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Science china Mathematics 2008年第8期51卷 1537-1548页

作者： ZHONG LiuQiang1,2,SHU Shi1,2,SUN DuDu3&TAN Lin4 1School of Mathematical and Computational Sciences,Xiangtan University,Xiangtan 411105,china 2Hunan Key Laboratory for Computation and Simulation in Science and Engineering,Xiangtan 411105,china 3Institute of Computational Mathematics and Scientific/Engineering Computing,Academy of Mathematicsand Systems Science,Graduate University of Chinese Academy of Sciences,Chinese Academy Sciences,P.O.Box 2719,Beijing 100190,china 4Department of Math-Physics,Nanhua University,Hengyang 421001,china 1. School of Mathematical and Computational Sciences Xiangtan University Xiangtan 411105 China 2. Hunan Key Laboratory for Computation and Simulation in Science and Engineering Xiangtan 411105 China 3. Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Graduate University of Chinese Academy of Sciences Chinese Academy Sciences P.O. Box 2719 Beijing 100190 China 4. Department of Math-Physics Nanhua University Hengyang 421001 China

In this paper,we are concerned with the fast solvers for higher order edge finite element discretizations of Maxwell's *** present the preconditioners for the first family and second family of higher order N′ed′elec element equations,*** combining the stable decompositions of two kinds of edge finite element spaces with the abstract theory of auxiliary space preconditioning,we prove that the corresponding condition numbers of our preconditioners are uniformly bounded on quasi-uniform *** also present some numerical experiments to demonstrate the theoretical results.

关键词： preconditioner higher order edge finite element stable decomposition