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Investigation of PAT for Advanced Sulphoaluminate MDF Cement

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Journal of wuhan university of {2.(Materials science) 2005年第1期20卷 104-105页

作者：黄从运 school of Materials science and Engineering Wuhan University o f Technoloy Wuhan 430070China

The method of examining micro-pores in su lp hoaluminate MDF cement by means of the Positron Annihilation Technique (PAT) was *** results show that the intensity I 2.of positrons annihilation wi th moderate life-span (τ 2.330Ps) increases regularly with the addition of t he numbers of micro-pores (less than 2.0?). Therefore, the value of I 2.may b e used to opitomize the compactness and integrity of the MDF cement structure. A t the same time, the experiment result of PAT was compared with that of Mercury Intrusion Porosimeter (MIP).

关键词： sulphoaluminate MDF cement PAT MIP polyvinyl alcohol

METHOD TO SOLVE ELASTIC CONJUGATE SURFACES IN MULTI-TEETH MESHING

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Chinese Journal of Mechanical Engineering 2002年第4期15卷 348-352页

作者： Yi Chuanyunschool of Mechanical science and Engineering, Huazhong {2. of science and technology,wuhan 430074, china school of Mechanical science and Engineering Huazhong University of Science and Technology Wuhan 430074

A method to solve the elastic conjugate surfaces in multi-teeth meshing ispresented. In mechanical manufacturing and design, there exist a lot of problems relating toconjugate surfaces, such as three-dimensional engagement, steel rolling and workpiece machining,which cause great effects on the quality of machining and performances of transmission. This methoddescribes relation between conjugate motion and elastic deformation in the process of mesh-in andmesh-out, and can be used to determine the profile of gear tooth by a certain given load sharing.

关键词： multi-teeth meshing elastic conjugate surfaces

VIBRATION AND CONTROL IN RING ROLLING PROCESS

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中国有色金属学会会刊：英文版 1999年第2期9卷 9-13页

作者： Hua Lin1, 2. Mei Xuesong2.and Wu Xutang2.1 school of Materials science and Engineering,{2. Automotive Polytechnic university, wuhan 430070, P. R. china2.school of Mechanical Engineering,Xian Jiaotong university, Xian 710049, P. R. china 武汉汽车工业大学材料科学与工程学院湖北武汉西安交通大学机械工程学院陕西西安

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１ＩＮＴＲＯＤＵＣＴＩＯＮＲｉｎｇｒｏｌｉｎｇｉｓａｎｉｍｐｏｒｔａｎｔｍｅｃｈａｎｉｃａｌｐｒｏｃｅｓｉｎｇｐｒｏｃｅｓｗｈｉｃｈｉｓｓｕｉｔａｂｌｅｆｏｒｐｒｏｄｕｃｉｎｇｄ５０～１００ｍｍｒｉｎｇｐａｒｔｓｏｆｄｉｆｅｒｅｎｔｍａｔｅｒｉａ...

关键词： ring rollingvibrationstabilityprocess control

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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science china Earth sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3, QU Jing1 & ZHAO Wenxia4 1. Graduate school, china {2. of Geosciences, wuhan 430074, china 2. Test Center, china {2. of Geosciences, wuhan 430074, china 3. Physics and technology College, wuhan {2., wuhan 430072. china 4. Test Center, Zhongshan {2., Guangzhou 5102.5, china china Univ Geosci Grad Sch Wuhan 430074 Peoples R China china Univ Geosci Test Ctr Wuhan 430074 Peoples R China wuhan Univ Phys & Technol Coll Wuhan 430072 Peoples R China Zhongshan Univ Test Ctr Guangzhou 510275 Peoples R China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463 nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3m and Fd3m, respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F4132. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Kinetics of the Thermal Decomposition of Wangjiatan Siderite

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Journal of wuhan university of {2.(Materials science) 2011年第3期26卷 523-526页

作者：冯志力 Huazhong university of science and {2.

The thermal decomposition processes of Wangjiatan siderite samples were studied in nitrogen by thermogravimetric（TG）*** mechanism of thermal decomposition of the siderite obeyed an F n kinetic law and the n-order was between 1.16 and *** results from non-isothermal experiments show that the size of particles has an obvious effect on the logarithm of pre-exponential factor in kinetics parameter of the thermal decomposition of Wangjiatan siderite.A linear relationship is shown between the size of particles and the logarithm of pre-exponential *** F 1 kinetic model containing size factor describes the thermal decomposition of Wangjiatan siderite well.

关键词： thermal decomposition mechanism kinetics siderite

PREPARATION OF IRON CARBIDE FROM MAGNETITE PELLETS BY CO-H_2.MIXTURES REDUCTION

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 280-284页

作者： H. W Ni1), D.Q. Cang2. and J.P. Jiang2. 1) school of Materials and Metallurgy, wuhan {2. of science and technology, wuhan 430081, china 2. school of Metallurgy, {2. of science and technology Beijing, Beijing 100083, Chi Sch. of Mat. Wuhan Univ. of Sci. and Technol. Wuhan 430081 China

A method of preparing iron carbide by reducing magnetite pellets with H2.CO mixtures is presented. The results show that an over 90 percent conversion ratio of iron carbide can be reached at 973 K and 1073 K under the suitable atmosphere. The reaction process to prepare iron carbide from magnetite pellets can be divided into two stages: reduction of magnetite pellets and carburization of reduction products. The carbon deposition has a great influence on the formation of iron carbide. In order to get a high conversion ratio of iron carbide, the relative weight loss value (m) should be controlled between 0.5 to 0.8.

关键词： Carbides Fabrication Magnetite Ore pellets Reduction

A PARALLEL NUMERICAL MODEL OF SOLVING N-S EQUATIONS BY USING SEQUENTIAL REGULARIZATION METHOD

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Journal of Hydrodynamics 2003年第1期15卷 72-77页

作者： Project supported by the National Natural science Foundation of china. (Grant No:6977302.)Zhang She sheng, Zou Zao jian, Xiang Ping bo {2. of science, wuhan university of technology, wuhan 430063, china school of science Wuhan University of Technology Wuhan 430063 China

A parallel numerical model was established for solving the Navier-Stokesequations by using Sequential Regu-larization Method (SRM). The computational domain is decomposedinto P sub-domains in which the difference formulae were obtained from the governing equations. Thedata were exchannged at the virtual boundary of sub-domains in parallel computation. Theclose-channel cavity flow was solved by the implicit method. The driven square cavity flow wassolved by the explicit method. The results were compared well those given by Ghia.

关键词： parallel computer sequential regularization method (SRM)

Computationally efficient channel estimation and inter-carrier interference suppression for OFDM communication systems

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The Journal of china Universities of Posts and Telecommunications 2009年第6期16卷 17-23页

作者： CAI Meng,ZHANG Ke-feng,ZOU Xue-cheng,LIU Hao school of Electronics of science and {2.,Huazhong university of science and {2.,wuhan 430074,china [a] school of Electronics of science and {2. Huazhong university of science and {2. wuhan 430074 china

This article puts forward a novel channel estimation and inter-carrier interference（ICI） suppression method for time-varying orthogonal frequency division multiplexing（OFDM） *** proposed adaptive finite impulse response（FIR） filter utilizes the time domain correlation of the *** on the one order auto-regressive（AR） model,a modified Kalman filter is exploited to track the channel *** solving the Yule-Walker equation,the coefficient of the AR process can be obtained from zero order Bessel ***,when the channel is assumed not perfectly known,the above criterion will lead to an impractical *** deal with it,the coefficient of the AR process is taken as a *** a new state space model is deduced and *** results show that the proposed method can work effectively at the speed of 144 km/h with a phase noise of -85 dBc/Hz at 100 kHz *** proposed method yields an improvement bit error rate（BER） compared with three of the existing algorithms with much lower complexity.

关键词： channel estimation OFDM ICI phase noise Kalman filter

Influence of Rare Earth Co-dopant on the Photocatalytic Property of TiO_2.Nano-particles

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Journal of wuhan university of {2.(Materials science) 2010年第3期25卷 370-374页

作者：徐晓虹 school of Materials science and Engineering Wuhan University of Technology

A series of nanometer TiO2.photocatalysts co-doped respectively with rare earth Er^3＋-Ce^3＋ and La^3＋-Fe^3＋ were prepared by sol-gel method,and the photocatalytic activity under ultra-violet light was evaluated by photocatalytic degradation of methyl *** crystallographic forms,particles size,and morphology were characterized by XRD and *** results showed that the optimum heat temperature of co-doped TiO2.was 550 ℃,and the co-doped TiO2.kept *** anatase crystal had the average size of 2. *** co-doping caused red-shift of the UV-Vis absorption spectra and enhanced the absorption of *** with the spectrum of pure TiO2.photocatalysts,the red-shift of Er^3＋-Ce^3＋ co-doping and La^3＋-Fe^3＋ co-doping catalysts was 53 nm and 34 nm,*** co-doping amount for Er^3＋-Ce^3＋ was n（Er^3＋）：n（TiO2.=0.1%,n（Ce^3＋）：（TiO2.= 0.05% and La^3＋-Fe^3＋ was n（La^3＋）：n（TiO2.=0.05%,n（Fe^3＋）：（TiO2.=0.5%.Under the condition the photocatalysis properties of the samples can be *** was found that the catalytic activity correlated well with the *** degradation rate of methyl blue examined at two hour of the reaction was 92.37%,and the better photocatalysis properties than the non-doped TiO2.were *** co-doped photocatalyst on methyl blue degradation follows the apparent first-order kinetics.

关键词： nano-TiO2 rare earth co-doped photocatalytic degradation sol-gel method