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Journal of Rare Earths 2004年第Z1期22卷 79-83页

作者： Yu Ning Ji Jingwen College of Sciences Northeastern University Shenyang 110004 China College of SciencesNortheastern University Shenyang 110004 China

The expression of critical size of ferromagnetic microcrystal in an external magnetic field with an intensity of H is derived by means of comparing energies of domain structure *** ferromagnetic microcrystal here means an ferromagnetic single crystal with the size which is smaller than L0, and L0 is the critical value of the size of single-domain particles at the external magnetic field intensity H =***, the coercive strength H(Ls) relating to the size of microcrystal Ls is given and quantitatively evaluated with the material SmCo5 as an *** is thus concluded that if L0 ＞ Ls ＞ LC, the antimagnetization of microcrystal will be subjected to a multi-domain process just like the particles of a size greater than L0, only if Ls ＜ LC, the anti-magnetizaton will be carried on in accordance with the Stoner-Wohlforth mechanism( LC is the maximum size of microcrystal with MHcth ).It is suggested that the material RECo5 is available to make an advanced magnet with MHC = 2 K/Mc.

关键词： magnetization mechanism coercive force ferromagnetic microcrystal

Study on the structural characteristics of graphitized carbon microcrystal prepared from PI film using X-ray diffraction technique

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Science China(Technological Sciences) 1998年第1期41卷 1-5页

作者：赵根祥钱树安陶琨 Shanxi Institute of Coal Chemistry Chinese Academy of Sciences Talyuan China Department of Materials Science Tsinghua University Beijing China

The structural characteristics of the graphitized carbon microcrystal prepared from carbonized polyimide (PI) film were explored using X-ray diffraction technique. The experimental results show that the graphitization of the thin film was initiated by heat treatment around 2 100℃; the carbon layers of the thin film specimens heat-treated at 2 825℃ and above possessed good orientation, the phenomenon of poly-phase graphitization appeared markedly, and the information of the mosaic structure of the sample was obtained; the interlayer spacing and the mosaic degree for 3 160℃ heat-treated thin film samples are 0.335 45 nm and 5.4°, respectively. As far as the source of two crystal phases with a slight difference in graphitization degree is concerned, some inferences are discussed, which helps understand more about the structure of the graphitization products.

关键词： PI film graphitization carbon microcrystal mosaic structure X-ray diffraction.

Spectra of excitons in R-phycoerythrin microcrystals

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Chinese Science Bulletin 1995年第14期40卷 1211-1215页

作者：汪河洲郑锡光赵福利毛卫东高兆兰余振新朱晋昌蒋丽金张季平梁栋材 Institute of Laser and Spectroscopy Zhongshan University Guangzhou 510275 China Institute of Photographic Chemistry. Chinese Academy of Sciences Beijing 100101 China Institute of Biophysics Chinese Academy of Sciences Beijing 100101. China

The antenna system of photosynthetic organisms serves to absorb light energy andtransfer excitation energy to the reaction centers. Energy transfer in the antenna system hasbeen found to be very efficient and rapid. The overall transfer efficiency exceeds 90％, andthe whole process of energy transfer from the phycoerythrin (PE) to the reaction center iscompleted within 50 ps in intact cells of red algae and cyanobacteria. Phycobilisome. the important photosynthetic antenna in red algae and cyanobacteria,consists of antenna polypeptide rods and core. One side of the core attaches to thethylakoid membrane and connects with the reaction center. the other side connects with

关键词： R-phycoerythrin microcrystal exciton photosynthesis energy transfer.

ALPHA-PHASE microcrystalLINE STRUCTURE OF IONITRIDING LAYER ON STEELS

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Acta Metallurgica Sinica(English Letters) 1992年第8期5卷 149-151页

作者： LI Ji YUAN Yongsheng Northeast University of Technology,Shenyang,ChinaYUAN Keqi University of Science and Technology Beijing,Beijing,China

TEM observation on the ionitriding layer was carried out on steels W18Cr4V,38CrMoAl and 1Cr18Ni9Ti,and AES of elementary analysis was also made on the outer surface of ionitrid- ing layer of austenitic stainless *** due to the ion-bombardment effect,a microcrystalline structure with texture was affirmed along surface of the ionitriding *** may be affected by cathodic sputtering and absorption that the atomic ratio of Cr/Fe in- creases and of Ni/Fe decreases on surface of nitriding layer on austenitic stainless steel 1Cr18Ni9Ti,thus the α-phase microcrystalline structure occurrs.

关键词： ionitriding microcrystal surface structure

LOCALIZED CORROSION OF microcrystalS OF 1Crl8Ni9Ti STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 1989年第8期2卷 143-145页

作者： LIU Dacheng CAO Chunan WANG Fuhui LOU Hanyi ZHANG Lixin

The resistances against localized corrosion of 1Cr18Ni9Ti microcrystals with normal grain size and bcc structure obtained hy magnetron sputtering have been *** two kinds of microcrystals with (110) and (211) textures respectively were obtained under different sputtering *** microcrystals were found to have better resistance against local- ized corrosion than the crystal with normal *** microcrystal with (110) preferred orientation has larger resistance to localized corrosion than that with (211) preferred orientation.

关键词： microcrystal localized corrosion magnetron sputtering

Microstructure and Optical Properties of the (1-x)GeS2-xP2S5 Glasses

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Journal of Wuhan University of Technology(Materials Science) 2006年第2期21卷 139-141页

作者：龚跃球赵修建 Key Laboratory of Silicate Materials Science and Engineering (Wuhan University of Technology) Ministry of Education Wuhan 430070 China Key Laboratory of Silicate Materials Science and Engineering (Wuhan University of Technology) Ministry of Education Wuhan 430070 China

To find materials with larger second-order nonlinearity, the Ge-P-S chalcogenide glasses with various ratios of GeS2∶P2S5 were prepared by the melt-quenching method. The microstructure and optical properties of these glasses were characterized by XRD, Raman, Vis-NIR spectroscopy and Maker fringe *** second harmonic generation （SHG） was observed in the as-prepared chalcogenide glasses which was ascribed to the thermal stress gradient and/or the microanisotropic defects （such as the lone-pair orbital or the valence alternative pairs） prefer-orientation of the as-prepared glasses.

关键词： chalcogenide nonlinearity microcrystal defects

Quantitative analysis of microstructure of carbon materials by HRTEM

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Transactions of Nonferrous Metals Society of China 2006年第S2期 796-803页

作者： YANG Jun-he, CHENG Shu-hui, WANG Xia, ZHANG Zhuo, LIU Xiao-rong, TANG Guo-hua Department of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 200235, China School of Chemical Engineering, East China University of Science and Technology, Shanghai 200000, China

The main object of the present research is to make a quantitative evaluation on the microstructure of carbon materials in terms of microcrystal. The digitized images acquired from finely pulverized carbon materials under HRTEM at a high magnification were processed by the image processing software so as to extract the fringes of (002) lattice of graphite crystal from the background image, and an FFT-IFFT filtering operation was performed followed by processes as binarization for the image and skeletonization for the fringes. A set of geometrical parameters including position, length and orientation was set up for every lattice fringe by calculating the binarized image. Then, the above obtained fringe parameters were put into an algorithm, which was especially developed for such fringe images so as to find fringes that could be regarded as those belonged to one single graphite microcrystal. The fringe was subjected sequentially to comparing procedures with every other fringe on aspects as parallelism, relative position and spacing, and the above comparisons were repeated till the last fringe. Eventually, the microcrystal size, its stacking number, and the distribution of the microcrystal in the whole sample, as well as other related structure information of such microcrystal in carbon materials were statistically calculated. Such microstructure information at nanometer level may contribute greatly to the interpretation of the properties of carbon materials and a better correlation with the same macrostructure.

关键词： carbon materials microcrystal digitized images quantitative analysis HRTEM

Crystal Growth of ZnO Microneedles in Water Containing Microbubbles

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New Journal of Glass and Ceramics 2014年第3期4卷 49-54页

作者： Yomei Tokuda Hiroaki Matsuki Yoshikatsu Ueda Hirokazu Masai Toshinobu Yoko Institute for Chemical Research Kyoto University Kyoto Japan Research Institute for Sustainable Humanosphere Kyoto University Kyoto Japan

Microbubble technology is now available in a wide range of industrial fields. The liquid containing microbubbles possesses a large number of air-liquid interfaces, and also generates radicals during bubble collapse. Here, we synthesized ZnO powder to explore the potential of microbubbles as starting materials for the formation of crystalline micro- or nanoparticles. The bubbles facilitated the growth of ZnO microneedles in high yields, and enhanced the reaction by radicals generated on bubble collapsing.

关键词： Microbubble microcrystal ZnO