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Wave propagation and energy dissipation in viscoelastic granular media

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Journal of Central South University 2001年第3期13卷 185-188页

作者： SUN Ye-zhi 1, WU Ai-xiang 1, LI Jian-hua 1,2 (1. College of Resources, Environment and Civil Engineering, Central South Unive rsity, Changsha 410083. china 2. the 5th Building Company in Guangdong province, Shaoguan 512026, china) 1. College of Resources Environment and Civil Engineering Central South University 410083 Changsha China 2. the 5th Building Company in Guangdong province 512026 Shaoguan China

In terms of viscoelasticity, the relevant theory of wave i n granular media is analyzed in this paper. Under the conditions of slight deforma tion of granules, wave equation, complex number expressions of propagation vecto r and attenuation vector, attenuation coefficient expressions of longitudinal wa ve and transverse wave, etc, are analyzed and deduced. the expressions of attenu ation coefficients of viscoelastic longitudinal wave and transverse wave show th a t the attenuation of wave is related to frequency. the higher the frequency is, the more the attenuation is, which is tested by the laboratory experiment. In a ddi tion, the energy dissipation is related to the higher frequency wave that is abs orbed by granular media. the friction amongst granular media also increase the e nergy dissipation. During the flowing situation the expression of transmission f actor of energy shows that the granular density difference is the key factor whi ch leads to the attenuation of vibrating energy. this has been proved by the exp eriment results.

关键词： viscoelastic granular media wave motion energy dissipation flowing situation

Determination of gemcitabine and its metabolite in human plasma using high-pressure liquid chromatography coupled with a diode array detector

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Acta Pharmacologica Sinica 2004年第12期25卷 18-23页

作者： Neng-ming LIN2,3. Su ZENG2,4, Sheng-lin MA3. Yun FAN3. Hai-jun ZHONG3. Luo FANG3. 2Collegeof Pharmaceutical Sciences, Zhejiang University, Hangzhou 3.003. 3.hejiang Cancer Hospital, Hangzhou 3.0022, china College of Pharmaceutical Sciences Zhejiang University Hangzhou 310031 China

AIM: To establish a high pressure liquid chromatography (HPLC) method for determination of the concentration of gemcitabine (dFdC) and its metabolite(dFdU) in human plasma. MEthODS: Plasma 1.0 mL spikedwith floxuridine as an internal standard was extracted with 3.0 mL of methanol-acetonitrile (v/v, 1:9). the supernatant was evapo- rated at 60 oC and the residue was reconstituted with 0.5 mL of the solution used as the mobile phase. After centrifugation, 50 μL of the supernatant was injected into the HPLC system. Separation was achieved on a C18 (4.6 mm×250 mm, 5 μm) column at 25 oC with the flow rate of the mobile phase set to 0.8 mL/min. the compounds were detected at 268 nm. the mobile phase consisted of 40.0 mmol/L acetate ammonium buffer solution (pH 5.5) and acetonitrile (v/v, 97.5:2.5). RESULTS: the linear range was 0.20-10.0 mg/L(r=0.9999) for dFdC and 0.50-50.0 mg/L(r=0.9999) for dFdU. the limit of detection (LOD) was 0.10 mg/L for dFdC and 0.25 mg/L for dFdU, while the limit of quantification (LOQ) was 0.20 mg/L (RSD3.%) for dFdU. the average recovery of dFdC and dFdU by this method were 103.3.% and 98.7 %, respectively. For intra-day and inter-day, the corresponding standard deviations of the measurements of dFdC and dFdU were both less than 5.5 %. CONCLUSION: An analytical method was established to measure the concentrations of dFdC and dFdU in human plasma and was effectively applied to the dFdC and dFdU pharmacokinetic studies of 8 Chinese patients with malignant tumors.

关键词： high pressure liquid chromatography gemcitabine deoxycytidine floxuridine

CJZ3.a Iomerizine derivative,modulates P-glycoprotein function in rat brain microvessel endothelial cells

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Acta Pharmacologica Sinica 2006年第4期27卷 414-418页

作者： Bian-sheng JI~2 Ling HE~3.Xiao-qu LI~4 Guo-qing LIU~(3.5) ~2Institute of Pharmacy,Henan University,Kaifeng 475001.china ~3.epartment of Pharmacology,china Pharmaccutical University.Nanjing 210009,china:~4School of Life Sciences,Beijing Normal University,Beijing 100875,china Institute of Pharmacy Henan University Kaifeng China Department of Pharmacology China Pharmaceutical University Nanjing China School of Life Sciences Beijing Normal University Beijing China

Aim:To investigate the modulatory effect of CJZ3.a lomerizine derivative,onP-glycoprotein(P-gp)function in rat brain microvessel endothelial cells(RBMEC).Methods:RBMEC were isolated and cultured in Dulbecco's modified Eagle's me-dium/F12(1:1)medium,and the amount of intracellular rhodamine 123.Rh 123.wasdetermined using a fluorescence spectrophotometer to evaluate the modulatoryeffect of CJZ3.on P-gp ***:the accumulation of Rh 123.was poten-tiated in a concentration-dependent manner after incubation with CJZ3.for RBMEC,but not for human umbilical vein endothelial cells(HUVEC).CJZ3.caused theaccumulation of intracellular Rh123.in a time-dependent manner and significantlydecreased the effiux of Rh 123.from the *** inhibitory effect of CJZ3.on P-gpfunction was reversible and remained for 120 min after CJZ3.2.5 μmol/L)wasremoved from the ***:CJZ3.has a potent in vitro effect on theinhibition of P-gp function.

关键词： CJZ3 P-glycoprotein blood-brain barrier

Morphological Evolution of Nb_2O_5 in a Solvothermal Reaction: From Nb_2O_5 Grains to Nb_2O_5 Nanorods and Hexagonal Nb_2O_5 Nanoplatelets

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 245-248页

作者：胡卫兵 School of Chemical and Environmental Engineering Hubei Institute for Nationalities Department of Physics Huazhong University of Science and Technology

Novel Nb2O5 nanorods and polygonal Nb2O5 platelets were generated by a simple solvothermal technique. the geometry evolution of the resultant Nb2O5 from amorphous nanoparticles to crystallized particles, from polygonal platelets to well-elongated nanorods was been studied in detail. the processing parameters, including the reaction temperature, reaction time, concentration of the precursors, and pH value of the solution, which affect the shape and size of the nanorods, were investigated. the Nb2O5 nanorods with different aspect ratios were examined by XRD, SEM and TEM. the experimental results show that Nb2O5 nanorod is the orthorhombic structure and well-crystallized. the growth of the nanorods follows their [001] direction. the successful generation of high quality Nb2O5 nanorods is not only important for transition metal oxide research, but also potentially important for further formation of new Nb-based 1-D nanostructures, such as NbS2 and NbN.

关键词： solvothermal morphological evolution Nb2O5 nanomateraials

Screening of Proteins Interacting with Nonstructural 1 Protein of H5N1 Avian Influenza Virus from T7-phage Display Library

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Chemical Research in Chinese Universities 2012年第1期28卷 103-107页

作者： ZHU Chun-yu1,2, SUN Ting-ting2, ZHAO Jian1,2, WANG Ning1,2, ZHENG Fang-liang1, AI Hai-xin1, ZHU Jun-feng1,2, WANG Xiao-ying3. ZHU Ying4, WU Jian-guo4 and LIU Hong-sheng1,2 1. Key Laboratory of Animal Resource and Epidemic Disease Prevention of liaoning province, 2. Research Center for Computer Simulating and Information Processing of Bio-macromolecules of liaoning province, Academy of Science, liaoning University, Shenyang 11003., P. R.{3. 3. Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing 100050, P. R.{3. 4. State Key Laboratory of Virology, Wuhan University, Wuhan 43.072, P. R.{3. liaoning Univ Acad Sci Key Lab Anim Resource & Epidem Dis Prevent Liaoni Shenyang 110036 Peoples R China liaoning Univ Acad Sci Res Ctr Comp Simulating & Informat Proc Biomacrom Shenyang 110036 Peoples R China Chinese Ctr Dis Control & Prevent Inst Nutr & Food Safety Beijing 100050 Peoples R China Wuhan Univ State Key Lab Virol Wuhan 430072 Peoples R China

Avian influenza virus（AIV） nonstructural 1（NS1） gene was amplified by real-time polymerse chain reac tion（RT-PCR） and inserted into pET28a, then transformed into E. coli BL21（DE3. competent cell. With the induction of isopropyl-β-D-thiogalactoside（IPTG） and the purification of Ni-NTA column, we finally obtained purified NS1 protein. T7-phage display system was used to screen the proteins that interacted with NS1 from lung cell cDNA li brary. the selected positive clones were identified by DNA sequencing and analyzed by BLAST program in Gene Bank. Two proteins were obtained as NS1 binding proteins, Homo sapiens nucleolar and coiled-body phosphoprotein 1（NOLC1） and Homo sapiens similar to colon cancer-associated antigen. By co-immunoprecipitation and other me thods, Homo sapiens NOLC1 was found to interact with the NS1 protein, the results would provide the basis for fur ther studying biological function of NS1 protein.

关键词： T7-phage display Nonstructural 1 (NS 1) protein Interacting protein

Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

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Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2,3.4, WANG Kemin1,2,3.4, XIAO Zhiqiang5,6, WANG Wei1,3.4, TAN Weihong1,2,3.4, SUN Yi5,6, TANG Hongxing1,3.4 & YANG Xiaohai1,3.41. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan University, Changsha 410082, china 2. Life Science and Biotechnology Institute, Hunan University, Chang- sha 410082, china 3. Chemistry and Chemical Engineer College, Hunan University, Changsha 410082, china 4. Hunan Engineering Research Center for Bio-Nanotechnology, Hunan University, Changsha 410082, china 5. Medical Experiment Research Center, Xiangya Hospital, Central South University, Changsha 410008, china 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Changsha 410008, china State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China Chemistry and Chemical Engineer College Hunan University Changsha China Hunan Engineering Research Center for Bio-Nanotechnology Hunan University Changsha China Medical Experiment Research Center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

the effects of drug treatment, gene transfection, and p53.RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53.with RNAi technology in normal expression cell line of CNE2. the level of ING1 varied from 7.7×10?16 to 53.4× 10?16 mol/μg total RNA of tumor cells. the results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA

Temperature and precipitation trends in Minqin Desert during the period of 1961-2007

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Journal of Arid Land 2011年第3期3卷 214-219页

作者： ShuJuan ZHU1,2,3.ZhaoFeng CHANG1,2,3.1 Gansu Minqin National Field Observation & Research Station on Ecosystem of Desertified Rangeland,Minqin 73.3.0,china 2 Key Laboratory of Desertification Combating of Gansu province,Lanzhou 73.070,china 3.Gansu Desert Control Research Institute,Lanzhou 73.070,china Gansu Minqin National Field Observation and Research Station on Ecosystem of Desertified Rangeland Minqin 733300 China Key Laboratory of Desertification Combating of Gansu province Lanzhou 733070 China Gansu Desert Control Research Institute Lanzhou 733070 China

this paper analyzed the data of temperature and precipitation in Minqin,typical desert area in north-west china,during the period of 1961 2007 by linear *** result indicated that the increasing rate of the mean annual temperature in Minqin was higher than that of the average of china;and the temperature in February increased by 3.01oC averagely in the past 47 *** climate in Minqin displayed an evident warming ***,there was no evidently increasing trend of precipitation in the past 47 years,and drought occurred during the whole growing season.

关键词： temperature precipitation global climate Minqin

Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3.ZHANG FuChun3.ZHANG ZhiYong4,LU ShuYuan5 & YANG YanNing3.1 Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710068,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3.College of Physics and Electronic Information,Yan’an University,Yan’an 716000,china 4 Information Science and Technology Institution,Northwest University,Xi’an 710127,china 5 Department of Telecommunications,Xi’an Institute of Posts and Telecommunications,Xi’an 710121,china 1. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710068 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. College of Physics and Electronic Information Yan’an University Yan’an 716000 China4. Information Science and Technology Institution Northwest University Xi’an 710127 China5. Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an 710121 China

the electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).the calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3. electron spins and Fe 3. electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3. electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

the Juancheng chondrite──A new meteorite falling recently in china

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Chinese Science Bulletin 1998年第21期43卷 1834-1837页

作者： CHEN Yongheng 1,2, WANG Daode+2 and WANG Ruitian+3.. Department of Chemistry, Guangzhou Normal University, Guangzhou 510400, china 2. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 3. Heze Bureau of Seismolo Department of Chemistry Guangzhou Normal University Guangzhou China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Heze Bureau of Seismology Shandong Province Heze China

the Juancheng chondrite, a new meteorite falling recently in Juancheng County, Shandong province, china, is classified as an H5 (S2) chondrite based on the compositions of olivine (Fa= 19.2, σ Fa=0.46) and low-Ca pyroxene (Fs=16.9, σ Fa=0.4). the plagioclase in the Juancheng chondrite is rich in CaO, indicating a relatively high metamorphic temperature the parent body underwent.

关键词： Juancheng ordinary chondrite new meteorite.