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生物工程学报 2003年第3期19卷 261-266页

作者：彭力徐志南方向明吴金民岑沛霖浙江大学生物工程研究所杭州310027 浙江大学医学院附属邵逸夫医院中心实验室杭州310016

人防御素是近年发现的人体内重要的内源性抗生素 ,已引起国内外生物和医学研究者的日益重视。这里综述了人防御素的组织分布、分子生物学特点、作用机理、医学及药用价值等方面的研究进展 ,对采用基因重组方法生产人防御素的方法进行了... 详细信息

人防御素是近年发现的人体内重要的内源性抗生素 ,已引起国内外生物和医学研究者的日益重视。这里综述了人防御素的组织分布、分子生物学特点、作用机理、医学及药用价值等方面的研究进展 ,对采用基因重组方法生产人防御素的方法进行了评述 ,并展望了防御素的应用前景和发展趋势。

关键词：抗菌肽组织分布分子生物学作用机理人防御素

Direct Electrodeposition of Cu-Ni-W Alloys for the Liners for Shaped Charges

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Journal of Materials Science & Technology 2010年第5期26卷 429-432页

作者： Hanwei He and Shouya Jia State Key lab of Powder Metallurgy,central South University,Changsha 410083,china State Key lab of Powder Metallurgy Central South University Changsha 410083 China

The Cu-Ni-W alloys for the liners for shaped charges were successfully prepared by direct current（DC） *** influence of cathode current density on morphology,microstructure and composition of the Cu-Ni-W alloys was investigated by means of scanning electron microscopy（SEM）,X-ray diffraction（XRD） and energy dispersive spectrometry（EDS）.With the increasing of current density,the copper content reduces gradually and the nickel and tungsten content increase; the crystallite size is *** the current density is 15 A/dm 2 the tungsten content reaches 12.96 wt pct,and the crystallite size is submicron *** Cu-Ni-W alloy is face-centered cubic（fcc） solid *** of the Cu-Ni-W alloys take on（220） texture.

关键词： Electrodeposition Cu-Ni-W alloy Cathode current density

A Novel Method for Preparation of TaC Coating on C/C Composite Material

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Journal of Materials Science & Technology 2005年第3期21卷 381-385页

作者： Hanwei HE, Kechao ZHOU and Xiang XIONG State Key lab of Powder Metallurgy, central South University, Changsha 410083, china lab. of Powder Metallurgy Central South University Changsha 410083 China

A new method for preparation of TaC coating on C/C composite material is reported. The amorphous ethylate tantalum jellied as the precursor is prepared and spread densely on the surface of the C/C composite material so as to form a multilayer film. In a graphitization furnace the multilayer film is transformed into TaC coating at various temperatures. Ethylate tantalum film is characterized by FT-IR (Fourier transform infrared) spectra, XRD (X-ray diffraction) and SEM (scanning electron microscopy) and TaC coating is characterized by XRD and SEM. At 1200℃ the coating contained TaC and Ta2O5, and at above 1400℃ only TaC is formed. The coating formed at 1600℃ is a continuous stratum structure, and that formed at 1600℃ is a porous net structure. Analysis on thermodynamics and formation mechanism of TaC indicates that, after ethylate tantalum is decomposed, Ta2O5 is first produced and then transformed into Ta2C, and newly formed Ta2C is transformed into TaC by the sufficient C at last.

关键词： C/C composite TaC coating Ethylate tantalum

Expanded Industrial Experiments of Free-alkali Recovery from Sodium Tungstate Solution by the Membrane Electrolysis Process

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Rare Metals 2001年第2期20卷 121-125页

作者： Liansheng Xiao, Qixiu Zhang, Guiqing Zhang, Bofan Gong (Metallurgical Separation Science and Engineering lab, central South University, Changsha 410083, china) 中南大学湖南长沙 410083

The expanded industrial experiments were conducted with practical industrial liquor to separate free alkali from sodium tungstate solution by electrolysis with cation-exchange membrane. Experimental results show that on the condition that the temperature is 50-55 degreesC and the current density is 1000 A/m(2), the single electrolysis cell is operated stably and 80% free-alkali in mass fraction is separated from the anode feed liquor of sodium tungstate, with electric efficiency up to more than 88% and the unit energy consumption E lower than 1900 kWh/t; while three electrolysis cells in series are operated, under the condition that the temperature is 60-65 degreesC and the current density is 1000 A/m(2), the electric efficiency can reach higher than 88% and the unit energy consumption E can be lower than 2250 kWh/t.

关键词： sodium tungstate membrane electrolysis

Improving Densification and Mechanical Properties of FeAl/TiC Composites by Addition of Ni

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Journal of Materials Science & Technology 2003年第1期19卷 73-76页

作者： Yong LIU, Fengxiao LIU, Baiyun HUANG, Kechao ZHOU, Yuehui HE and Zhihong TANGNational Key lab for P/M, central South University, Changsha 410083, china lab. for P/M Central South Univ. Changsha 410083 China

FeAl/TiC composites were fabricated by hot pressing blended elemental powders. The effects of Ni-doping on thedensification and mechanical properties of the composites were studied. Results show that the density of the composites decreases with the content of TiC increasing, and the addition of Ni significantly improves the densificationprocess by enhancing mass transfer in the bonding phase. The mechanical properties of the composites are closelyrelated with their porosity. Besides increasing the density of the composites, the addition of Ni improves the mechanical properties by other three effects: solution-strengthening the bonding phase, strengthening the FeAI-TiC interfaceand increasing ductile fracture in FeAl phase.

关键词： of in it on TiC Improving Densification and Mechanical Properties of FeAl/TiC Composites by Addition of Ni by

Industrial application of the technique of removing Mo by a combination of moving packed bed and fluidized bed ion exchange

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Rare Metals 2003年第2期22卷 81-85页

作者： XIAO Liansheng, ZHANG Qixiu, GONG Bofan, and HUANG ShaoyingMetallurgical Separation Science and Engineering lab., central South University, Changsha 410083, china (Received 2002-05-08) Metallurgical Separation Science and Engineering lab. Central South University Changsha 410083

The application of the technique of removing molybdenum by moving packed bedand fluidized bed ion-exchange in a factory was described. The data showed that the Mo removalefficiency is above 99 percent, and the Mo content in APT (Ammonium Paratungstate) is controlledsteadily below 18 X l0^(-6), in the case of treating the feed liquor containing Mo 1.4 g/L. Thetechnique is simple and convenient in operation, good reusability of resin, loss consumption ofdesorption reagent and little pollution on environment. The loss of tungsten is less than 0.5percent. The technique bas been proved to be an economical and efficient process for Mo removal.

关键词： non-ferrous metallurgy separation ion-exchange moving packed bed fluid bed molybdenum tungsten.

Electrodeposition of Copper by IMPC Method

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Journal of central South University 2000年第4期12卷 186-190页

作者： ZHOU Kang gen,LI Qing gang,ZHANG Qi xiu (Metallurgical Separation Science and Engineering lab., central South University, Changsha 410083, china) Metallurgical Separation Science and Engineering lab. Central South University Changsha China

In order to develop an energy saving electrodeposition process of copper, the electrodeposition of copper in copper sulfate solution by the ion exchange membrane primary cell (IMPC) method has been studied. The experiments were carried out in an ion exchange membrane primary cell with dimensions of 200 mm in length, 52 mm in width and 90 mm in height. The influences of temperature(294 323 K), interval between the anode and cathode (1.5 3.5 cm), mass concentrations of Cu 2+ (6 40 g/L), H 2SO 4(0 120 g/L) and Fe 3+ (3 9 g/L) in catholyte and solution flow rate (0 8 cm/s) on current density and current efficiency were investigated experimentally. The current density increases with the increase of temperature and concentrations of Cu 2+ and H 2SO 4 in catholyte. Cathode current efficiency decreases with the increase of concentration of Fe 3+ in catholyte and anode current efficiency decreases with the increase of temperature. The high quality cathodic copper can be obtained and the current density of membrane can be higher than 150 A/m 2 and the current density of cathode can be higher than 300 A/m 2. The experiment results show that IMPC method is effective for electrodeposition of copper.

关键词： ion exchange membrane primary cell copper electrodeposition

CREEP BEHAVIORS OF Mg MICROALLOYED WROUGHT SUPERALLOYS

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Acta Metallurgica Sinica(English Letters) 1990年第3期3卷 208-212页

作者： MA Peili YUAN Ying ZHONG Zengyong central Iron and Steel Research Institute,Ministry of Metallurgical Industry,Beijing,china MA Peili Senior Engineer,lab.of Superalloy,central Iron and Steel Research Institute,Ministry of Metallurgical Industry,Beijing 100081,china

By adding small amount of Mg to the wrought superalloys,the steady stage of creep,and es- pecially the tertiary stage of creep are ***,the steady creep rate is decreased within the range of low strain *** higher strain rates,however,the effect of Mg on creep rate *** may be attributed to the Mg dissolution in the matrix.A mechanism of the effects of Mg addition on creep behaviors is proposed.

关键词： Mg microalloying creep wrought superalloy activation energy of vacan-

Microstructural evolution of TiAl base alloy during three-stepped thermo-mechanical treatment

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Journal of central South University of Technology 2001年第1期8卷 9-12页

作者： LIU Yong,LIU Feng xiao,HUANG Bai yun,ZHOU Ke chao,ZHANG Chuan fu (State Key lab for Powder Metallurgy, central South University, Changsha 410083, china) State Key lab for Powder Metallurgy Central South University Changsha China

A TiAl base alloy ingot with a height to diameter ratio of 2.2 was broken down by multiple step canned forging. The microstructures after every deformation and subsequent recrystallization were observed by optical microscopy. Results show that at the first step the reduction should be carefully controlled in case of double bulge and crack of the ingot. After the first annealing, recrystallization occurred at the deformed grain boundaries and inside the grain. The recrystallized microstructure is favorable for further deformation. After the second deformation and annealing, coarsening of the lamellae occurred and the microstructure became equiaxed. By the final deformation and subsequent recrystallization, the coarse lamellar colony can be refined to about 20 μm, and homogeneous microstructure was obtained from the ingot with a large initial height to diameter ratio.

关键词： TiAl base alloy hot forging microstructure