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MCM-41 Prepared with Ionic Liquid and Cethytrimethylammonium Bromide as Co-templates

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Journal of wuhan university of technology(Materials Science) 2009年第1期24卷 25-29页

作者：张光旭 School of Chemical Engineering Wuhan University of Technology college of Chemistry and Molecular sciences Wuhan University

The mesoporous molecular sieves MCM-41 were prepared using room tempera-ture ionic liquid （RTIL） synthesized in laboratory and cethytrimethylammonium bromide （CTAB） as compound templates for the first time. They were prepared under low aging temperature and short aging time. Via characterizing by XRD and nitrogen adsorption instrument, MCM-41 synthesized by this new method exhibited good crystal structure and narrow pore distribution. The following pre-paratory conditions was optimal： the molar ratio of RTIL to CTAB was 1.0∶1.0, aging at 80 ℃, for 40 h and calcined at 540 ℃. It is found that the acidified MCM-41 improves its activity as catalyst over the unmodified ones.

关键词： mesoporous molecular sieve hydrothermal crystallization co-templates ionicliquid MCM-41

DOUBLE Φ-FUNCTION INEQUALITY FOR NONNEGATIVE SUBMARTINGALES

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 211-216页

作者： MEI TAO(college of Mathematics and Computer Sciences, wuhan {2., wuhan 430072. china.) LIU PEIDE(college of Mathematics and Computer Sciences, wuhan {2., wuhan 430072. china.) college of Mathematics and Computer Sciences Wuhan University Wuhan 430072 China

The authors establish a kind of inequalities for nonnegative submartingales which depend on two functions　ψ and ψ, and obtain the equivalent conditions for　Φ and ψ such that this kind of inequalities holds. In t... 详细信息

关键词： Matingale Nonnegative submartingale Maximal function Φ-function inequality

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3, XUE Qiong4 (1. School of Mechanical Engineering and Automation, wuhan Textile university, wuhan 430073, Hubei, china 2. State Key Laboratory of Material Processing and Die and Mould technology, Huazhong university of Science and technology, wuhan 430074, Hubei, china 3. wuhan Zhike Abrasive-Resistant Material Science and technology Development Co Ltd, wuhan 430073, Hubei, china 4. college of Science, wuhan university of technology, wuhan 430079, Hubei, china) School of Mechanical Engineering and Automation Wuhan Textile University Wuhan Hubei China State Key Laboratory of Material Processing and Die and Mould technology Huazhong University of Science and Technology Wuhan Hubei China wuhan Zhike Abrasive-Resistant Material Science and technology Development Co Ltd Wuhan Hubei China college of Science Wuhan University of Technology Wuhan Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

A New Modified GM (1,1) Model: Grey Optimization Model

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Journal of Systems Engineering and Electronics 2001年第2期12卷 1-5页

作者： Xiao Xinping college of Scienced, wuhan university of technologyl {2., P R. china Deng Julong Dept. of Control, Huazhong university of Science and technology, wuhan 430074,P. R. china college of Sciences Wuhan University of Technology 430063 P. R. China Dept. of Control Huazhong University of Science and Technology Wuhan 430074 P. R. China

Based on the optimization method, a new modified GM (1,1) model is presented, which is characterized by more accuracy prediction for the grey modeling.

关键词： GM (1,1) Grey optimization model Optimization method.

Polarity for a Class of Levy Processes

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wuhan university Journal of Natural Sciences 2002年第4期7卷 394-398页

作者： Wu Chuan ju 1,2., Liu Lu qin 1 1. School of Mathematics and Statistics, wuhan university, wuhan 430072. Hubei, china 2. college of Urban Construction, wuhan university of Science and technology, wuhan 430070, Hubei, china School of Mathematics and Statistics Wuhan University Wuhan Hubei China college of Urban Construction Wuhan University of Science and Technology Wuhan Hubei China

Polar set of Markov processes is an important concept in probabilistic potential theory, but it is not easy to judge the polarity of the sets. In this paper, we give some results which can be easily used to examine the polarity of the sets whenX t belongs to a special class of Levy processes. We also give a result about polar functions of symmetric stable processes.

关键词： Levy process subordinator (essentially) polar set polar function

A New Clustering Algorithm for Categorical Attributes

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 318-322页

作者： Songfeng Lu, Zhengding Lu (college of Computer Science and technology, Huazhong {2. of Science and technology, wuhan 430074, china) college of Computer Science and technology Huazhong University of Science and Technology Wuhan 430074 China

In traditional data clustering, similarity of a cluster of objects is measured by distance between objects. Such measures are not appropriate for categorical data. A new clustering criterion to determine the similarity between points with categorical attributes is pre- sented. Furthermore, a new clustering algorithm for categorical attributes is addressed. A single scan of the dataset yields a good clus- tering, and more additional passes can be used to improve the quality further.

关键词： data mining clustering similarity Information

Commission Strategy of the Auction House

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wuhan university Journal of Natural Sciences 2006年第3期11卷 507-510页

作者： WANG Yan~ 1,2.1. college of Economics, Fudan university, Shanghai 2.0433,{2. 2. School of Mathematics and Statistics, wuhan university , wuhan 430072. Hubei,{2. college of Economics Fudan University Shanghai China School of Mathematics and Statistics Wuhan University Wuhan Hubei China

In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders＇ equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.

关键词： auction commission proportion Bayesian equilibrium bidding strategy

1.55 μm Wavelength Operation of E_r^(3+) -Doped Optical Fiber Bistability

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wuhan university Journal of Natural Sciences 1999年第4期4卷 435-438页

作者： SONG Qian 1, ZHANG Yuan cheng 2.1. college of Electronics Information, wuhan {2., wuhan 430072. china 2. Department of Physics, wuhan {2., wuhan 430072. china wuhan university College of Electronics Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

An all optical all fiber optical bistability operation has been realized in an all fiber cavity consisted with Er doped fiber and optical fiber loop mirrors. The experimental bistability threshold is consistent w... 详细信息

关键词： optical nonlinearity optical bistability Er doped fiber all fiber device

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2.& YUAN XianBao1,3 1 college of Science, china Three Gorges {2., Yichang 443002. china 2.School of Physics and technology, wuhan {2., wuhan 430072. china 3 Institute of Particle Physics, Central china Normal {2., wuhan 430070, china college of Science China Three Gorges University Yichang China School of Physics and technology Wuhan University Wuhan China Institute of Particle Physics Central China Normal University Wuhan China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power