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A Mechanical Model for Three-phase Permanent Deformation of Asphalt Mixture under Repeated Load

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Journal of Wuhan university of Technology(Materials science) 2009年第6期24卷 1001-1003页

作者：赵永利 School of Transportation Southeast University

On basis of the Burgers model, a new model consisting of modified dashpot and Van Der Poel model was derived from rheological and viscoelastic theory. Subsequently, triaxial repeated load permanent deformation tests of AC16 asphalt mixtures were conducted to validate this new developed model. Parameters of new developed model were obtained by a nonlinear regression analysis of test data, and then permanent strains and flow number of each mixture were calculated. The experimental results prove that the new developed model can well describe three phases permanent deformation of asphalt mixture under repeated load and it can be used for pavement mechanical analysis and rutting prediction.

关键词： asphalt mixture permanent deformation three phases theory triaxial repeated load

Expression and Identification of Mutated Osteoprotegerin in Culture Cells and Larvae of Silkworm

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 331-335页

作者： Hai-Long XIAO, Yong-Feng JIN, and Yao-Zhou zhang1* Institute of Biochemistry, college of Life sciences, Zhejiang university, Hangzhou 310029, china college of Life sciences, Zhejiang university of science & Technology, Hangzhou 310018, china Institute of Biochemistry College of Life Sciences Zhejiang University Hangzhou 310029 China college of Life sciences Zhejiang University of Science & Technology Hangzhou 310018 China

The mutated osteoprotegerin (OPG-372) gene was inserted into the baculovirus transfer vector pBacPAK8, and the recombinant plasmid was co-transfected with linearized Bm-BacPAK6 virus DNA into BmN cells, then homologous recombination occurred inside the cells. The recombinant virus BmNPV-OPG- 372 was screened and identified by Southern blotting. The recombinant human OPG-372 was expressed in cultured cells and the larvae of silkworm by inoculation of recombinant virus. The expression products were run on the SDS-PAGE and their immunoreactivities were determined by Western blotting. It was found that a 42 kD recombinant protein was expressed in BmN cells and a 46 kD one in larvae respectively. The bioactivi- ties of the recombinant proteins were determined by hypocalcemic effect assay in the mice. The results showed that the recombinant proteins had a significant hypocalcemic effect on mice sera.

关键词： OPG-372 silkworm baculovirus expression system hypocalcemic effect

Influences of Sputtering Angles and Annealing Temperatures on the Magnetic and Magnetostrictive Performances of TbFe Films

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Journal of Materials science & Technology 2005年第3期21卷 315-318页

作者： Hongchuan JIANG, Wanli zhang, Wenxu zhang, Shiqing YANG and Huaiwu zhang college of Microelectronics and Solid State Electronics, university of Electronic science and Technology of china, Chengdu 610054, china college of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China

To increase the low-field magnetostriction of TbFe films, the influences of sputtering angles and annealing temperatures on its magnetic and magnetostrictive performances were systematically investigated. With the change in sputtering angles from 90° to 15°, the in-plane magnetization of TbFe films, at 1600 kA·m-1 external field, is strongly increased. An enhancement in the in-plane magnetostrictive coefficient of the films at 40 kA·m-1 is also observed. A detection of magnetic domains by MFM (magnetic force microscopy) indicates that the easy magnetization direction shifts gradually from perpendicular to parallel to the film plane with decreasing sputtering angles. Annealing can enhance the magnetization and magnetostriction of the TbFe films. However, at too high annealing temperature, both the magnetization and magnetostriction of the TbFe films were suppressed to some extent.

关键词： TbFe films Oblique sputtering Annealing Magnetization Magnetostriction

Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

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science china(Life sciences) 2007年第6期50卷 808-813页

作者： LIU YuQing1,3, zhang HuaiQiang2, SHEN JianZhong3 & GAO PeiJi2 1 Institute of Animal science and Veterinary Medicine, Shandong Academy of agricultural science, Jinan 250100, china 2 State Key Laboratory of Microbial Technology, Shandong university, Jinan 250100, china 3 college of Veterinary Medicine, china agricultural university, Beijing 100094, china Institute of Animal science and Veterinary Medicine Shandong Academy of Agricultural Science Jinan China college of Veterinary Medicine China Agricultural University Beijing China State Key Laboratory of Microbial Technology Shandong University Jinan China

According to the instantaneous growth rate (dN/dt) of E. coli CVCC249 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase; declining phase, in each of which obvious variation in physiological; biochemical properties was detected, including total DNA, total protein,; MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N 0/{1+exp[r·(x-BC 50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC 50 represents the mean level of susceptivity, while the bactericidal span BC 199=(2lnN 0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC249 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase; declining phase all increased compared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity; research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

关键词： instantaneous growth rate, batch culture, physiological heterogeneity, concentration-killing curve, antibiotic susceptivity test

Hepatitis gene chip in detecting HBV DNA, HCV RNA in serum and liver tissue samples of hepatitis patients

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Hepatobiliary & Pancreatic Diseases International 2003年第2期2卷 550-557页

作者： Wei Zhao Jian-Min Wan Wei Liu Quan-Jun Liu Lin zhang Zhen-Xian Zhou Xin-Jue Liu Han-Rong zhang the college of Biological science and Technology, nanjing Agriculture university, nanjing 210014, china Department of Liver Disease Research, nanjing 2nd Hospital, Southeast university. nanjing 210003, china National Laboratory for Molecular and Biomolecular Electronics (Chien-Shiung Wu Laboratory), Southeast university, nanjing 210096, china college of Biological science and Technology Nanjing Agriculture University Nanjing 210014 China. wanjm@***

OBJECTIVE: To study the preparation of diagnostic gene chip for detecting hepatitis B virus (HBV) and hepatitis C virus (HCV) and its accuracy in detecting HBV DNA and HCV RNA in serum and liver tissues. METHODS: The probes, which depend on the conservative gene fragment of hepatitis virus, was designed, synthesized and spotted on the modified glass. The probes and some other control probes were assembled on the diagnostic microarray of hepatitis virus. The gene of hepatitis virus, purified from blood or tissue, was labeled with fluorescence and hybridized to the microarray. The hybridized microarry was scanned with microarray scanner and the diagnostic result was analyzed from the scanning data. Fourty patients with hepatitis B virus and 40 healthy people or 40 patients with hepatitis C virus were subjected to detection of HBV DNA and HCV RNA with the hepatitis virus gene chip by the double-blind method. Paraffin liver specimens obtained from 99 cases of posthepatitic cirrhosis were used to detect HBV DNA. The liver tissues and serum from 15 cases of chronic hepatitis B were used to detect HBV DNA. Simultaneously, HBsAg and HBcAg were detected in the serum by fluorescence microparticle quantitation, HBV DNA and HCV RNA in the serum by PCR, and HBcAg in liver tissues by immunocytochemistry or HBV DNA by in situ molecular hybridization. RESULTS: Chip detection of serum specimens showed that 30 patients were HBV DNA positive and 10 HBV DNA negative in the 40 patients with HBV positive, 25 patients were HCV RNA positive and 15 patients were HCV RNA negative in the 40 patients with HCV positive, and all were HBV and HCV negative in the 40 healthy people. In 15 patients with HBV marker positive who were subjected to liver biopsy, 15 patients were detected HBV DNA positive in serum by gene chip, 15 patients HBcAg positive in liver tissues by immunocytochemistry, 14 patients HBV DNA positive in liver tissues by in situ molecular hybridization, and 14 patients HBV DNA posit

关键词： hepatiti gene chip serum liver tissue

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 Assoc. Prof. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China Prof. China Institute of Water Resources and Hydropower Research Beijing 100038 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

Damage detection based on the propagation of longitudinal guided wave in a bimetal composite pipe

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Theoretical & Applied Mechanics Letters 2011年第2期1卷 20-24页

作者： Huixing Yun~(1,a) and Weiwei zhang~2 1.college of Engineering Shanxi agricultural university,Taigu 030801,china 2.college of science & Engineering,Jinan university,Guangzhou,china college of Engineering Shanxi agricultural university Taigu 030801 China college of science & Engineering Jinan University Guangzhou China

This paper investigates the damage detection based on the propagation of guided wave in bimetal composite pipes,which can identify damage locations in both axial and circumferential *** feasibility of the method is showed by numerical simulations using FEM code ANSYS. Mode analysis is used to evaluate the guided wave mode and its structure,which can provide the basis of the mode selection in measurements *** guided wave propagation in a damaged pipe is computed by transient analysis.16 nodes around the pipe wall,as probes,are used to record the guided wave *** Pseudo Margenau-Hill distribution(PMHD)for each signal is carried out, three types of modes could be found,which are led mode,excited mode and lag mode in sequences. Based on the results,the arrival time of the excited mode could be used to locate damage in axial direction,and the energy distribution around the pipe of lag mode is consistent with the damage in circumferential *** simulation illustrated the possibility of detecting damage location in both axial and circumferential directions based on longitudinal ultrasonic guided waves only.

关键词： damage detection crack PMHD pipe

Performance tests of multi-metal zincate solutions with zinc sulfate and zinc oxide

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Rare Metals 2007年第S1期26卷 99-104页

作者： HUANG Xiaomei,and zhang Milin college of Materials science and Chemical Engineering,Harbin Engineering university,Harbin 150001,china Harbin Engn Univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron *** was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc ***,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was ***,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the *** results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating *** zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.

关键词： Al-Si alloy multi-metal zincating solution adhesion

Spectral wave transformation model for simulating refrac-tion-diffraction with strongly reflecting coastal structures

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Acta Oceanologica Sinica 2011年第2期30卷 25-32页

作者： ZHENG Jinhai NGUYEN Viet Thanh zhang Chi State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering HohaiUniversity Nanjing 210098 China college of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

On the basis of the wave action balance equation which incorporates refraction,diffraction,reflection and wave-current interaction,a directional spectral wave transformation model WABED is developed for predicting the irregular wave refraction-diffraction with strongly reflecting structures in coastal *** the model,diffraction is taken into account by introducing a term formulated from a parabolic approximation wave equation,and reflection is calculated through a back-marching numerical approach at the reflecting *** experimental data sets are used to examine the performance of present model with regard to wave characteristics around reflecting coastal *** is from a physical experiment at idealized inlet with parallel jetties,while the other is from a laboratory study on a coastal project of the concave *** good agreements are found for both cases,revealing the applicability of the present model for predicting combined wave refraction-diffraction processes with strongly reflecting coastal structures.

关键词： Wave Height Coastal Structure Spectral Wave Wave Prediction Spectral Wave Model