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The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of sciences, P. O. Box 800-2.1, Shanghai 2.1800, china 2. {2. of Physics, Shandong normal university, Jinan 2.0014, china 3. Shandong Institute of Architecture and engineering, Jinan 2.0014, china 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. department of Physics Shandong Normal University 250014 Jinan China 3. Shandong Institute of Architecture and engineering 250014 Jinan China

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Effect of Limestone Powder on Microstructure of Concrete

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Journal of Wuhan university of Technology(materials {2.) 2010年第2期25卷 328-331页

作者：刘数华 State Key Laboratory of Water Resource and Hydropower engineering science Wuhan University

The effect of limestone powder on microstructure of concrete was studied by using mercury intrusion porosimetry （MIP）, backscattering scanning electron（BSE）, scanning electron mi- croscopy （SEM） and X-ray diffraction （XRD） techniques. The experimental results show that the compressive strength of concrete containing 100 kg/m3 limestone powder can meet the strength requirement. Limestone powder has not pozzolanic activity; it is still unhydrated at the age of 2. days. But its filling effect can make the paste matrix and the interfacial transition zone between matrix and aggregate denser, which will improve the performance of concrete.

关键词： concrete limestone powder microstructure filling effect hydration characteristic

Controlled free radical polymerization of styrene initiated from the alkoxyamine-functionalized silicon surface

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science china Chemistry 2005年第5期48卷 449-458页

作者： CHEN Zhijun1, ZHOU Sikai1, LU Wenzhong1, FANG Shaoming1, JIANG Xiqun2.& YANG Changzheng2.1. College of materials and Chemical engineering, Zhengzhou {2. of Light Industry, Zhengzhou 450002. china 2. Laboratory of Mesoscopic Material science and department of Polymer science & engineering, College of Chemistry & Chemical engineering, Nanjing {2., Nanjing 2.0093, china 1. College of materials and Chemical engineering Zhengzhou University of Light Industry 450002 Zhengzhou China 2. Laboratory of Mesoscopic Material science and department of Polymer science & engineering College of Chemistry & Chemical Engineering Nanjing University 210093 Nanjing China

We describe a new method of fabricating a brush-like polystyrene layer anchored on the surface of the silicon substrate, which involves three steps, namely (i) the attachment of 3-methacryloxypropyltrimethoxysilane onto the silicon surface; (ii) the reaction of vinyl moiety at another extremity of the anchored 3-methacryloxypropyltrimethoxysilane to 4-Hydroxyl-2. 2. 6, 6-tetramethyl-1-piperidinyloxy (HTEMPO?) catalyzed by azobisisobutyronitrile (AIBN); (iii) living free radical grafting polymerization of styrene in the presence of HTEMPO?. The controllable living free radical polymerization permits accurate control of both the molecular weight and the polydispersity. X-photoelectron spectroscopy measurement proved that the alkoxyamine initiator layer forms on the silicon surface. XPS and Ellipsometry measurements showed that the poly-styrene chains were covalently anchored onto the silicon surface. The thickness of the grafted polymer layer can be accurately manipulated by altering the polymerization time. The new method allows synthesizing random copolymer and block copolymers by the sequential growth of monomers from the substrate surface.

关键词： polymer brush, controlled living free radical polymerization, thickness, atomic force microscopy, 3-methacryloxypropyltrimethoxysilane.

Chemical Extraction Preparation of Delithiated Cathode materials of Li-ion Battery

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Journal of Wuhan university of Technology(materials {2.) 2009年第6期24卷 863-866页

作者：闫时建 School of materials science and {2. Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2.2.8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Analysis on cohesive crack opening displacement considering the strain softening effect

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science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2.& ZHAO Xiqiang3 1. Mechanics department, Shandong university of Technology, Zibo 2.5049,{2. 2. Civil engineering department, Dalian university of Technology, Dalian 11602.,{2. 3. Mathematics department, Ocean university of{2., Qingdao 2.6071,{2. Mechanics department Shandong University of Technology Zibo 255049 China Civil engineering department Dalian University of Technology Dalian 116024 China Mathematics department Ocean University of China Qingdao 266071 China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

Development of simple sequence repeats (SSR) markers of ramie and comparison of SSR and inter-SSR marker systems

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Progress in Natural science:materials International 2005年第02期15卷 42-47页

作者： ZHOU Jianlin1*, JIE Yucheng2., JIANG Yanbo2. ZHONG Yingli1, LIU Yunhai1 and ZHANG Jian1**(1. department of Biochemistry and Molecular Biology, College of Life science, Hunan {2. university, Changsha 410081, china 2. Institute of Bast Fiber Crops, Chinese Academy of Agricultural science, Changsha 410006, china) department of Biochemistry and Molecular Biology College of Life Science Hunan Normal University Changsha 410081 China. Institute of Bast Fiber Crops Chinese Academy of Agricultural Science Changsha 410006 China

Ramie (Boehmeria nivea L.) is an important bast fiber crop. To study genetic background of this species, we isolated and characterized microsatellite markers of ramie. A genomic library containing inserts of rapid amplification of polymorphic DNA (RAPD) fragments was constructed, and screened by PCR amplification using anchored simple sequence repeats as primers. A total of 2. clones were identified as positives, and 13 microsatellite loci were found after sequencing. The polymorphism of these 13 microsatellite loci was examined and the utility of simple sequence repeats (SSR) and inter-SSR (ISSR) marker systems for genetic characterization compared using 19 selected ramie cultivars. Both approaches successfully discriminated the 19 cultivars which differed in the amount of polymorphism detected. The level of polymorphism detected by SSR was 95.0%, higher than that by ISSR (72.3%), but the average polymorphism information content (PIC) of ISSR (0.651) was higher than that of SSR (0.441). The higher PIC value of ISSR suggests that ISSR is more efficient for fingerprinting ramie cultivars than SSR markers. However, because the SSR loci are codominant, they are more suitable for determining the homozygosity levels of ramie, constructing linkage map, quantitative trait loci study of complex traits and marker-assisted selection.

关键词： ramie (Boehmeria nivea L.Gaud) simple sequence repeats inter-simple sequence repeats

Measurement of the linear electro-optic coefficient of a minute cBN sample

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science china(Technological sciences) 2005年第2期48卷 233-340页

作者： DOU Qingping1, , MA Haitao1, JIA Gang1, CHEN Zhanguo1 2.& ZHANG Tiechen3 1. College of Electronic science and engineering, State Key Laboratory on Integrated Optoelectronics, Jilin {2., Changchun 13002., china 2. Mudanjiang normal Institute, Mudanjiang 157012. china 3. State Key Laboratory of Superhard materials, Jilin {2., Changchun 130012. china 1. College of Electronic science and engineering State Key Laboratory on Integrated Optoelectronics Jilin University 130023 Changchun China 2. Mudanjiang normal Institute 157012 Mudanjiang China 3. State Key Laboratory of Superhard materials Jilin University 130012 Changchun China

Cubic boron nitride (cBN) is a kind of artificial (synthetic) crystal. Transverse electro-optic modulation in a minute cBN sample was carried out. Basing on the practical form of the crystal, we established the theoretical and experimental method according to the sample. For the first time, the linear electro-optic effect was observed in cBN, and half-wave voltage of the cBN sample was measured successfully. Furthermore, its linear electro-optic coefficient was calculated at 1.17×10?14 m/V.

关键词： cBN crystal, linear electro-optic effect, half-wave voltage, linear electro-optic coefficient.

Chitosan——L-Lactic Acid Scaffold for the Regeneration of Peripheral Nerve and Its NGF Release Properties

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Journal of Wuhan university of Technology(materials {2.) 2009年第6期24卷 961-964页

作者：徐海星 department of Pharmaceutical engineering School of Chemical EngineeringWuhan University of Technology

Chitosan—L-lactic acid composite scaffold for the regeneration of peripheral nerve is obtained by grafting L-lactic acid onto the amino groups in chitosan with combined vacuum freezer drier. The composite scaffold was characterized by ATR-FTIR and SEM. The scaffold has a better graft efficiency and has a dense inner layer and a loose outer layer with porous structure, and the pore size is about 100 μ*** NGF release properties of the scaffold were investigated. The experimental results showed that, at the 1st day, 15.2.ng of NGF on average was released from the scaffold. From day 2.to day 10, the release rate obviously slowed down and 1.64 ng of NGF was released on average every day. After 10 days, the release rate was slower and 10.3 ng of NGF was released on average every day. After 60 days, NGF could also maintained a certain concentration. These properties show that the scaffold is a better carrier for NGF which can be more advantageous to the regeneration of the damaged peripheral nerve. As a result, this composite scaffold would be an ideal candidate for the regeneration of damaged peripheral nerve.

关键词： chitosan L-lactic acid peripheral nerve NGF release properties

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3, CHEN Jianmin2.& XUE Huaxin2.1. Center for Atmospheric Environment Study, department of Chemistry, Beijing normal {2., Beijing 100875, china 2. Center for Atmospheric Chemistry Study, department of Environ- mental science and engineering, Fudan {2., Shanghai 2.0433, china 3. LAPC/NZC, Institute of Atmospheric Physics, NZC/LAPC, Chinese Academy of sciences, Beijing 10002., china Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合