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Structure and Magnetic Properties of Ni-doped ZnO Powder

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Journal of wuhan university of {2.(Materials science) 2010年第5期25卷 770-773页

作者：高放赵俊 department of Electronic science and {2. Huazhong University of Science and Technology

Ni-doped ZnO nanopowder （Zn0.98Ni0.2.） was synthesized by improved coprecipitation method. The average particle size of the powder was estimated to be 50 nm. The powder was then processed by thermal treatment. Samples were annealed at 1 073, 1 2.3, and 1 473 K, respectively. The solubility of NiO in ZnO and the lattice parameters of ZnO both increased with the temperature. The magnetic property of the doped samples was examined, and hysteresis loops were got. The results showed all the samples were ferromagnetic, while powder processed at 1 2.3 K for 4 h got a highest saturation magnetization （Ms） of 0.0457 emu/g. Also, magnetic properties were related to the grain size of the powder.

关键词： ferromagnetism diluted magnetic semiconductor Ni-doped ZnO coprecipitation solid state reaction

MICROSTRUCTURE IN LASER FUSED HIGH SPEED STEEL W6Mo5Cr4V2.M2.

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Acta Metallurgica Sinica(English Letters) 1993年第1期6卷 36-39页

作者： LIU Ning CUI Kun huazhong university of science and technology,wuhan.China DENG Zonggang Hefei {2. of technology,Hefei,China CHENG Benpei KONG Jie Institute of solid state Physics,Academia Sinica,Hefei,China Doctorate student,department of Mechanical Engineering No.2.huazhong {2. of science and technology,wuhan {12.,China huazhong Univ of science and Technology Wuhan China

Microstructure of the deepest zone of high speed steel W6Mo5Cr4V2.M2.melt after laser fu-sion was found to be so fine as the ehill zone of a solidified *** narrower chill zoneformed,the long columnar dendrites grow into the melt and then the fine equiaxed cellularstructure appears in upper melt region nearly *** substructure of cellular grains anddendrites was observed to consist of martensite and retained austenile,while the carbides asM_6C_■ Cr_7C_3 and MC distributed at their *** is believed that the highermicrohardness up to HV_(0.1)=865-960 of the laser fused structure of the alloy is due to the oc-currence of martensite.

关键词： High speed steel W6Mo5Cr4V2.M2. laser fused treatment micrstructure

Effects of NaNbO_3-Co_2._3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of wuhan university of {2.(Materials science) 2007年第4期22卷 722-724页

作者：邓毅华 College of Material science and Engineering South China University of Technology department of Electronic science and {2. Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2.3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2.3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

Integrating　Knowledge－Based　Simulation　with　Aspiration－Directed　Model－based　Decision　Support　System

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Journal of Systems Engineering and electronics 1996年第2期7卷 25-33页

作者： Feng Shan & Li D. Xu(department of Automatic Control Engineering,huazhong {2. of science and technology wuhan, Hubei 430074, China)(department of Management science and Information systems Wright state {2., Dayton, OH 45435, USA) department of Automatic Control Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 China department of Management science and Information Systems Wright {2. university Dayton OH 45435 USA

This paper reports an aspiration-directed, model-based decision support system (AMDSS) integrated with a knowledge-based simulation system. The system is designed to study China's mid-range economic development strategy. The capacity of the system is enhanced by the knowledge-based component which provides a knowledge-based simulation environment for model management. Currently the system has passed the stage of prototype and achieves its implementation capacity. The paper first presents the mathematical aspects of decision making including aspiration-directed decision making, then discusses the architecture of the system. The purpose of the paper is to provide insights into how such an integrated system could provide decision support for complex decision analysis.

关键词： Knowledge-based simulation Model-based reasoning Decision support system

Experimental and theoretical study of^(13)C shielding tensors in new-style molybdenum complex

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science China Chemistry 2004年第3期47卷 214-221页

作者： HOU Guangjin1,2. WANG Liying2. LU Xiaoming3, ZHENG Anmin2. DENG Feng2.&YE Chaohui1,2.1. department of Physics, huazhong university of science and technology,{2., China 2. state Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, wuhan Institute of Physics and Mathematics, Chi-nese Academy of sciences, wuhan 430071, China 3. department of Chemistry, Capital Normal university, Beijing 100037, China department of Physics Huazhong University of Science and Technology Wuhan China Chinese Academy of sciences Wuhan China department of Chemistry Capital Normal University Beijing China

13C 2.-PASS spectra of two new cis-dioxo catecholatomolybdenum complexes (NH2.H2.H2.HCH2.2.H+)3[MovO 2.C6H4O2.2. and (NH2.H2.H2.H2.H2.2.H+)3[Mo(v)O2.(C2.2.2.2. have been obtained by solid-state nuclear magnetic resonance (NMR), in which the spinning sidebands were well-separated. The principal components of the 13C shielding tensors were extracted by theoretically fitting the intensities of 13C spinning sidebands. The effects of counter cations on 13C chemical shift isotropy and shielding tensor of cis-dioxo catecholatomolybdenum complex anion [Mo (v)O2.C6H4O2.2.3? were studied, comparing the 13C CSA of those carbon sites in complex anions with that of the counter cations. Based on the known structure of the molybdenum complex crystal, theoretical values of 13C shielding tensors were calculated by the ainitio GIAO method, in comparison with the experimental results.

关键词： NMR, magic angle spinning, chemical shift anisotropy, shielding tensor, cis-dioxo-monomolybdenum.

Miscibility of Semi-flexible Thermotropic Liquid Crystalline Copolyesteramide with Polyamide 66

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Chemical Research in Chinese Universities 2000年第4期16卷 356-362页

作者： XIE Xiao-Lin, TJONG S. C. and LI R. K. Y. (department of Chemistry, huazhong university of science and technology,{2. department of Physics and Materials science, City university of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong P. R. China) 华中科技大学湖北武汉 430074 香港城市大学香港

Liquid crystalline polymer-polyamide 66 (LCP/PA66) blends were compounded by using a Brabender mixing followed by compression moulding. The LCP employed was a semi-flexible liquid crystalline copolyesteramide based on 30% (molar fraction ) of p-amino benzoic acid (ABA ) and 70% (molar fraction) of poly (ethylene terephthalate) (PET). The LCP/PA66 blends were investigated in terms of the thermal and dynamic mechanical properties. It was found that PA66 and LCP components of the blends are miscible in the molten state, but are partially miscible in the solid state. The inclusion of the semi-flexible LCP into PA66 retards the crystallization rate of PA66. Furthermore, the melting temperature and the degree of crystallinity of PA66 are reduced considerably due to the LCP addition.

关键词： Polyamide 66 Semi-flexible copolyesteramide Miscibility

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肿瘤热疗中自动控温、恒温

生物化学与生物物理进展 1997年第6期24卷 504-506页

作者：赵振声李晖吴明忠詹继东华中理工大学固体电子学系武汉430074 华中理工大学生物工程系武汉430074 同济医科大学医疗系武汉430030

肿瘤热疗技术在临床上得到了较为广泛的应用 ,但是对于人体深层部位的肿瘤 ,由于热能难于传至并集中于肿瘤部位 ,肿瘤热疗效果不理想 .在当前肿瘤热疗中存在的另一个问题 ,即是准确、快速地测出热疗病灶部位的温度 ,仍然存在很大的困难 ... 详细信息

肿瘤热疗技术在临床上得到了较为广泛的应用 ,但是对于人体深层部位的肿瘤 ,由于热能难于传至并集中于肿瘤部位 ,肿瘤热疗效果不理想 .在当前肿瘤热疗中存在的另一个问题 ,即是准确、快速地测出热疗病灶部位的温度 ,仍然存在很大的困难 ,因而热剂量难于掌握 ,直接影响到肿瘤热疗的疗效 .由于锰锌铁氧体磁性微粉吸收剂具有强烈吸收电磁波和存在居里温度的特性 ,采用在肿瘤热疗过程中 ,将锰锌铁氧体磁性微粉吸收剂输入血管中 ,可以达到对肿瘤热疗自动控温。

关键词：肿瘤热疗自动控温恒温治疗

YSZ薄膜Sol-Gel法制备及其结构分析

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无机材料学报 1997年第2期12卷 200-206页

作者：章天金唐超群周东祥潘小龙华中理大学固电系武汉430074 华中理工大学物理系武汉430074

本文应用Sol－Gel方法制备了YSZ薄膜，研究了工艺条件对薄膜微观结构的影响.实验发现：基片的选择和清洁、样品的凝胶化速度、热处理过程中的升降温速率等是影响薄膜开裂的几个主要因素．XRD和SEM分析结果表明：应用Sol－Gel方法制备的... 详细信息

本文应用Sol－Gel方法制备了YSZ薄膜，研究了工艺条件对薄膜微观结构的影响.实验发现：基片的选择和清洁、样品的凝胶化速度、热处理过程中的升降温速率等是影响薄膜开裂的几个主要因素．XRD和SEM分析结果表明：应用Sol－Gel方法制备的YSZ薄膜，热处理温度须达800℃以上才能完全排除其中的酸根、有机基因和碳元素，且形成完整的立方相结构．薄膜经500℃、1h热处理后，其表面呈明显的海绵状结构．随着烧结温度的升高，薄膜表面变得致密，气孔明显减少，至1050℃时，薄膜表面光滑、无裂纹、无针孔、圆球形的小颗粒均匀分布．薄膜与衬底的结合紧密，薄膜厚度均匀，膜厚约为1.0μm.

关键词： YSZ薄膜薄膜结构分析溶胶凝胶法

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新颖的掺铒光纤放大器无源复合组件的研究

中国激光 1997年第8期24卷 741-744页

作者：刘水华虞国华方罗珍江山武汉邮电科学研究院固体器件研究所华中理工大学光电子工程系

报道了一种将光波分复用器与光隔离器集于一体的适用于掺铒光纤放大器的新颖复合组件。根据复合组件的性能指标对组件的结构参数进行了优化设计。实际制作的复合组件，得到泵浦光插入损耗＜０．６ｄＢ，信号光的插入损耗＜１．５ｄＢ，... 详细信息

报道了一种将光波分复用器与光隔离器集于一体的适用于掺铒光纤放大器的新颖复合组件。根据复合组件的性能指标对组件的结构参数进行了优化设计。实际制作的复合组件，得到泵浦光插入损耗＜０．６ｄＢ，信号光的插入损耗＜１．５ｄＢ，反向隔离度＞４２ｄＢ，体积为９×４５ｍｍ３。将复合组件用于掺铒光纤放大器中（前向泵浦方式）得到约３０ｄＢ的小信号增益，１０ｄＢｍ的饱和输出功率。

关键词：掺铒光纤放大器光隔离器无源复合组件