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Science china(Technological Sciences) 2009年第9期52卷 2742-2748页

作者： LEI YiFeng,LENG YongXiang,YANG Ping,WAN GuoJiang & HUANG Nan key laboratory of Advanced {2. Technology of ministry of education,Department of {2. Science and Engineering,Southwest Jiaotong university,Chengdu 610031,china key laboratory of Advanced {2. Technology of ministry of education Department of Materials Science and Engineering Southwest Jiaotong University Chengdu 610031 China

In this work,the relationship between electronic structure and hemocompatibility of oxygen deficient rutile TiO2.x was studied by both theoretical calculation and experimental study. Based on the local density functional theory,first-principals method was performed to calculate the electronic structure of rutile TiO2.with different oxygen vacancy concentration. In the range of less than 10% of (or equal) physically realistic O vacancy concentration,the band gap of rutile TiO2.increases with increasing O vacancy concentration,leading the TiO2.changes from a p-type to an n-type semiconductor. The valance band of TiO2.is predominated by O 2. orbital,while the conduction band is occupied by Ti 3d orbital for different O vacancy concentration. The O vacancy results in the occupation of electrons at the bottom of conduction band of TiO2.and the donor density increases with increasing O vacancy concentration. When {2. come in contact with blood,the n-type semiconductor feature of oxygen deficient TiO2.x with the bottom of conduction band occupied by electrons would prevent charge transfer from fibrinogen into the surface of {2.,thus inhibiting the aggregation and activation of platelets,therefore improving the hemocompatibility of rutile TiO2.x.

关键词： rutile TiO2 oxygen vacancy electronic structure hemocompatibility

Full-scale measurements of dynamic response of suspension bridge subjected to environmental loads using GPS technology

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Science china(Technological Sciences) 2010年第2期53卷 469-479页

作者： YI TingHua1,2. LI HongNan1 & GU Ming2.1State key laboratory of Coastal and Offshore Engineering, Dalian {2. of Technology, Dalian 11602., china 2.tate key laboratory for Disaster Reduction in Civil Engineering, Tongji {2., Shanghai 2.0092. china 1. State key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China2. State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China

Nowadays, there are many larger and taller engineering structures than in the past. These structures are commonly designed to be more flexible. Thus, they are sensitive to severe wind gust and earthquake tremor. For the dynamic response prediction, finite element (FE) modal updating and structural health monitoring, the dynamic characteristics of a structure are becoming increasingly important. The aim of this paper is to show an emerging tool-the real time kinematic (RTK) global positioning system (GPS), which is used to measure and monitor the low-frequency vibration of Dalian BeiDa Bridge, a medium span suspension bridge. The modal analysis is firstly performed on the developed three-dimensional FE model according to the original blue prints of the bridge to provide the analytical frequencies and mode shapes. The field ambient vibration tests using the accelerometers on the bridge deck are conducted just prior to the use of the GPS system in order to validate the FE model. And then, the calibration test is done to assess the dynamic displacement measurement accuracy of the GPS in three orthogonal directions. The GPS signal properties, such as the amplitude, standard deviations (STD), power spectral density (PSD), and probability density functions (PDF), are studied in details. After that, a structural health monitoring system based on the GPS is devised and installed on the bridge to provide real-time measurement of deck movement. The output-only modal parameter identification is carried out by using the Periodogram method to investigate the responses of the bridge. The result shows that the spectral densities of the displacements measured by the GPS correspond well with the results by the FEM analysis and the accelerometer vibration test. It is concluded that the GPS method is reliable and useful to clarify the ambient vibration response behaviors of the flexible structures. The integration of the GPS and accelerometer methods results in a hybrid arrangement tha

关键词： health monitoring global positioning system real-time kinematic suspension bridge modal analysis

Patterns of DNA cytosine methylation between haploids and corresponding diploids in rice

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Science Bulletin 2006年第14期51卷 1721-1728页

作者： ZHANG Hongyu1,2., PENG Hai1,2., LI Yun1,2. XU Peizhou1,2. WANG Xudong1,2.& WU Xianjun1,2.. Rice Research Institute of Sichuan Agricultural university, Wenjiang 611130, Sichuan 2. key {2. of Southwest Crop Genetic Resources and Improve-ment, ministry of education, Sichuan Agricultural university, Ya’an 62.014, china Rice Research Institute of Sichuan Agricultural university Wenjiang 611130 Sichuan key laboratory of Southwest Crop Genetic Resources and Improve- ment Ministry of Education Sichuan Agricultural University Ya''an 625014 China

Eighteen pairs of diploid-haploid twin-seedlings were identified and screened out fromspecial rice SARII-62. population. Five pairs of themwere selected and randomly designated as A, B, C, Dand E. Simple sequence repeats (SSR) analysisshowed that there was no difference among 310 siteswhich indicated that there was no base mutation onDNA primary structure. DNA methylation plays animportant role in gene expression regulation duringgrowth and development stages in eukaryotes. Amodified AFLP technique (methylation-sensitiveAFLP, MSAP) was employed to detect the DNA me-thylation patterns in the 5′-CCGG sites of the fivepairs of twin-seedlings. Although no methylationmutation was detected among the five diploids,forty-three methylation mutation sites were foundfrom the corresponding haploids. The MSAP ratios,which were the ratios of MSAP sites to the total am-plified sites, in five haploids were 18.79%, 19.35%,18.49%, 18.45% and 18.75%, respectively. And cor-responding full methylation levels (5′-CmCGG indouble strands) of those haploids were 10.58%,11.3%, 10.11%, 10.09% and 10.34%, *** MSAP and full methylation levels in the fivehaploids were higher than that of their correspondingdiploids, which suggested that hypermethylation oc-curred in some 5′-CCGG sites. Five types of MASPpatterns among the five pairs of twin-seedlings weredetected as follows: (1) no changes, methylation lev-els were the same in both haploids and diploids; (2. demethylation, diploid was methylated but no me-thylation in the same site in haploid; (3) hypermethy-lation, the methylation level in haploid was higher than those in diploid; (4) hypomethylation, methyla-tion in haploid was lower than those in diploid; (5) undecided pattern, change trend of methylation lev-els in haploids was not decided. The bands of 18 sites were reclaimed, then sequenced and searched on website to determine the sites of those sequences on rice chromosomes. The result showed that the methylation mutation in

关键词： rice twin-seedling diploid haploid DNA methylation MSAP.

Breakdown voltage analysis for the new RESURF AlGaN/GaN HEMTs

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Science china(Information Sciences) 2012年第2期55卷 473-479页

作者： DUAN BaoXing & YANG YinTang key laboratory of the {2. of education for Wide Band-Gap Semiconductor materials and Devices,School of Microelectronics,Xidian university,Xi’an 710071,china 1. key laboratory of the {2. of education for Wide Band-Gap Semiconductor materials and Devices School of Microelectronics Xidian University Xi’an 710071 China

This paper demonstrates that the depletion process for AlGaN/GaN high electron mobility tran-sistors(HEMTs)is different than that for silicon power devices by analyzing active region *** on the special breakdown principle that occurs in AlGaN/GaN HEMTs,we propose a new reduced surface field AlGaN/GaN HEMT with a double low-density drain(LDD)and a positively charged region near the drain to optimize the surface electric field and increase the breakdown *** this structure,two negative charge regions with different doses are introduced into the polarization AlGaN layer to form a double LDD and decrease the high electric field near the gate by depleting two-dimensional electron gas.A positively charged region is added to the electrode near the drain to decrease the high electric field peak at the drain *** applying ISE(integrated systems engineering)simulation software,we verify that the virtual gate effect occurs in the AlGaN/GaN *** breakdown voltage is improved from 2.7 V in the conventional structure to 550 V in the proposed structure.

关键词： AlGaN/GaN HEMTs breakdown voltage RESURF

Characterization and Crystal structure of a New Holmium(III) Complex with the Macrocyclic Ligand Derived from 2.6-Diformyl-4-methylphenol and Diethylenetriamine

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Chinese Journal of Structural Chemistry 2007年第12期26卷 1429-1434页

作者：胡学雷邱立赵元弟key laboratory of Biomedical Photonics of {2. of education - Wuhan National laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging key laboratory - key laboratory of Molecular Biophysics of the {2. of education Huazhong university of Science and Technology 潘志权 key laboratory of Biomedical Photonics of {2. of education - Wuhan National laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging key laboratory - key laboratory of Molecular Biophysics of the {2. of education Huazhong University of Science and Technology Hubei key laboratory of Novel Chemical Reactor and Green Chemical Technology Wuhan Institute of Technology

The title compound （13,2.-dimethyl-3,6,9,17,2.,2.-hexaazatricyclo-[2..***.1.1^11.15]- triaconta-l（2.）,2.9,11,13,15（30）,16,2.,2.,2.-decaene-2.,30-diol-N^3,N^6,N^9,O^2.,O^30）-bis（nitrato-O,O＇）- holmium（m） nitrate hydrate has been prepared and characterized by elemental analysis, infrared spectra, and electrospray mass spectra. Its crystal and molecular structures were determined by X-ray diffraction methods. The crystal crystallizes in the monoclinic system, space group C2.c with a = 2..737（12., b = 14.2.7（7）, c = 19.801（10） A, β = 91.36（1）^o, Mr = 831.57, V = 6690（6） A^3, Z = 8, Dc = 1.651 g/cm^3, F（000） = 3344, R = 0.0482.and wR = 0.092.. The holmium ion is located in one of the compartments of the macrocyclic ligand and presents a distorted tricapped trigonal prismatic coordination geometry. The macrocycle is coordinated with two oxygen and three nitrogen atoms. Two nitrates are chelated in the opposite positions of the macrocycle, and the third one is ionic.

关键词： crystal structure lanthanide macrocycle

Correlation between rheological behavior and structure of multi-component polymer systems

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Science china Chemistry 2008年第1期51卷 1-12页

作者： ZUO Min1,2.ZHENG Qiang1 1 key laboratory of Macromolecular Synthesis and Functionalization, {2. of education, Department of Polymer Science and Engineering, Zhejiang university, Hangzhou 31002., china 2.Department of Chemical Engineering, Hong Kong university of Science and Technology, Clear Bay, Kowloon, Hong Kong 1. key laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China 2. Department of Chemical Engineering Hong Kong University of Science and Technology Clear Bay Kowloon Hong Kong China

Rheological measurement has been an effective method to characterize the structure and properties for multiphase/multi-component polymers, owing to its sensitivity to the structure change of hetero- geneous systems. In this article, recent progress in the studies on the morphology/structure and rheological properties of heterogeneous systems is summarized, mainly reporting the findings of the authors and their collaborators, involving the correlation between the morphology and viscoelastic relaxation of LCST-type polymer blends, the microstructure and linear/nonlinear viscoelastic behavior of block copolymers, time scaling of shear-induced crystallization and rheological response of poly- olefins, and the relationship between the structure/properties and rheological behavior of filled polymer blends. It is suggested that a thorough understanding of the characteristic rheological response to the morphology/structure evolution of multiphase/multi-component polymers facilitates researchers’ op- timizing the morphology/structure and ultimate mechanical properties of polymer materials.

关键词： heterogeneous polymer systems morphology and structure rheological properties viscoelastic relaxation

Effect of Ultrafine Grinding on Dissolving-out Quantity of Tanshinone IIA from Radix Salvia Miltiorrhiza

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Journal of Wuhan university of Technology(materials Science) 2009年第6期24卷 973-976页

作者：苏艳丽傅正 College of Chemistry Chemical Engineering and Material ScienceSoochow UniversitySuzhou China State key laboratory of Advanced Technology for Material Synthesis and Processing Wuhan University of Technology

In order to improve the bioavailability, Radix salvia miltiorrhiza raw powder mixed with distilled water （5.5wt%） was ultrafinely ground to nanosize particles using HSCS pulverizer, and the dissolving-out quantity of tanshinone IIA in the filtrate that obtained from nanoparticles suspension and raw powder marinated in water for different time was determined by HPLC. The experimental results show that raw powder can be ultrafinely ground to 133.5 nm at 1500 r/min for 50 min and the molecular structure of active ingredients doesnot change, and the dissolving-out quantity of tanshinone IIA obtained from the filtrate is increased greatly from 12.77 μg/g to 54.55 μg/g.

关键词： Radix salvia miltiorrhiza tanshinoe IIA HPLC dissolving-out quantity

Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3)MnO_3 system

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Science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2.,YAN GuoQing 1,3 ,CAI ZhiRang 1 ,PI Li 2.,ZHANG Bei 2.&TONG Wei 2.1 Department of Physics,Suzhou College,Suzhou 2.4000,china 2.structure Research {2.,university of Science and Technology of china,Hefei 2.002.,china 3 National {2. of Solid State Microstructures,Physics Department,Nanjing university,Nanjing 2.0093,china 1. Department of Physics Suzhou College Suzhou 234000 China 2. structure Research laboratory University of Science and Technology of China Hefei 230026 China 3. National laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

structure and composition-dependent optical properties of(PbxSr1-x)TiO3（x=0.4,0.6） nanotube arrays

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Progress in Natural Science:materials International 2011年第3期21卷 198-204页

作者： Yan-ping JIANG~(1,2.,Xin-gui TANG~(1,2.,Yi-chun ZHOU~1,Qiu-xiang LIU~2.1.key laboratory of Low Dimensional {2. and Application Technology, Xiangtan university,Xiangtan 411105,china 2.School of Physics and Optoelectronic Engineering,Guangdong university of Technology, Guangzhou 510006,china [a] key laboratory of Low Dimensional {2. and Application Technology Xiangtan University Xiangtan 411105 China [b] School of Physics and Optoelectronic Engineering Guangdong University of Technology Guangzhou 510006 China

Lead strontium titanate(PbxSr1-x)TiO3（x=0.4,0.6） nanotubes were synthesized by sol-gel template method via spin *** structures and morphology of the as-prepared samples were characterized by X-ray *** electron microscopy and transmission electron microscopy.X-ray photoelectron spectroscopy was used to determine the chemical composition of the sample and the valence state of *** spectroscopy of the as-prepared(PbxSr1-x)TiO3（x=0.4,0.6） nanotubes at room temperature was also *** results indicate that as-prepared(PbxSr1-x)TiO3（x=0.4,0.6） nanotubes are perfectly crystallized and there is a trend of structure change from PST40 to PST60.A weak peak at 508 cm-1assigned to E（3TO） mode can be seen in the Raman spectrum of(Pb0.6Sr0.4)*** spectra of samples at room temperature reveal three intense emission bands centered at 356,400 nm for(Pb0.4Sr0.6)TiO3and 413,433,451 nm for(Pb0.6Sr0.4)TiO3nanotubes. *** peak positions of the emission band have a significant blue shift as Pb content increases.

关键词： (PbxSr1-x)TiO3 nanotube sol-gel AAO template Raman spectrum photoluminecsence

structure and Properties of Mg-doped SrBi_4Ti_4O_(15) Bi-layered Compounds

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Journal of Wuhan university of Technology(materials Science) 2008年第5期23卷 675-677页

作者：郝华 School of materials Science and Engineering Wuhan University of Technology State key laboratory of Advanced Technology for {2. Synthesis and Processing Wuhan University of Technology

The structure and properties of Mg-doped SrBi4Ti4O15（SBT） were dicussed. Mg substitution into SBT had two possibilities states with the dopant amount variety. Mg cation substituted mostly into Sr^2. and the amount proportion was 68.11%.Mg ion will substitute into Ti ion site in perovskite layer when the doping amount increases. Polarization increases sharply when x=0.1 and then decreases becauses of the domain pinning. The Curie temperature of Mg-doped SBT is about 300 ℃ and there is a broad diffuse phase transition near Tc with a flat peak near the Ta of SBT.

关键词： Mg-doped bismuth layer structure ferroelectrics ferroelectric properties