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Journal of wuhan university of {2.(Materials science) 2008年第3期23卷 407-410页

作者：靳素荣 school of science Wuhan University of Technology

The compound of diphosphopentamolybdate { [Cu（en）（Hen）]2.P2.o5O2.] }·3H2. [en=ethylenediamine] had been obtained from the hydrothermal method and characterized by single crystal X-ray diffraction, elemental analysis, FT-IR, and thermogravimetric analysis The structure consist of [P2.o5O2.]^6- clusters anions, complex [Cu（en）（Hen）]^3＋ cations and crystallization water molecules, which are held together to a two-dimensional framework The most interesting feature of the compound is that two nitrogen atoms are both coordinated with Cu（ Ⅱ ） in one ethylenediamine molecule, for the other ethylenediamine molecule, only one nitrogen atom is towards Cu（ Ⅱ） and the other nitrogen atom is protonated and formed Hen^＋.

关键词： polyoxometalate hydrothermal synthesis crystal structure coordination groups

Characteristics and Microstructure of Graphite Encapsulated Iron Nanoparticles

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Journal of wuhan university of {2.(Materials science) 2007年第2期22卷 214-217页

作者：曹宏 school of Materials science&Engineering Wuhan Institute of Technology

The graphite encapsulated a-Fe particles were prepared by reduction of stage-2.and stage-3 FeCI3 graphite intercalation compounds （GICs） with metallic potassium, X-ray diffraction analysis （XRD）, energy dispersive X-ray spectroscopy （EDS） investigation and transmission electron microscopy （TEM） observation show that the reduction products of stage-2.FeCl3-GICs contains more abundant a-Fe nanoparticles than those of stage-3. High-resolution TEM （HRTEM） observation reveals that the nanoparticle of a-Fe was polycrystals or twins, which was real or quasi two-dimension in shape, and whose space orientation was strictly controlled by the graphene. Based on the experiment results, a possible growth model of the graphite encapsulated ct-Fe was proposed.

关键词： encapsulated nanoparticle graphite intercalation compounds iron electron transmissionmicroscopy (TEM) template

Preparation and Characterization of Polylactide/Montmorillonite Nanocomposites

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Journal of wuhan university of {2.(Materials science) 2009年第4期24卷 562-565页

作者：吴选军 school of Chemical Engineering Wuhan University of Technology

The montmorillonite, a form of layered silicate, was successfully intercalated into polylactide （PLA） matrix through solvent-casting technique. In addition, PLA/MMT nanocomposite films were produced, in which homogenous distribution of the silicate lamellae plays a key role in the mechanical properties of the films. A small amount（5wt%） of OMMT intercalated into the PLA matrix resulted in their flexibility enhancement, from 3.68%（pure PLA film） to 352.65%. The results of wide-angle X-ray diffraction （WAXD） patterns confirmed that the silicate interlayer distance increased from 3.044 nm （for OMMT） to 3.56nm （for 5wt%, maximum） with increasing OMMT contents, but decreased to 3.319 nm when OMMT content was over 8wt%. FT-IR also verified the molecular-level associations between PLA chains and OMMT lamellae by vibration variances of hydrogen bonding. DSC thermograms demonstrated that thermal stabilities of the nanocomposite films enhanced, due to the silicate lamellae dispersed into PLA matrix.

关键词： polylactide montmorillonite nanocomposite characterization thermo-mechanic at property

On the Symmetry Classes of Functions

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wuhan university Journal of Natural {2.s 2005年第5期10卷 813-816页

作者： ZHU Ping~1,2. FAN Yun~3 1. school of Mathematics and Statistics, wuhan {2., wuhan 430072. Hubei, china 2. school of science, Beijing {2. of Posts and Telecommunications, Beijing 100876, china 3. school of Mathematics and Statistics, Huazhong Normal {2., wuhan 430079, Hubei, china wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Beijing university of Posts and Telecommunications School of Science Beijing China (GRID:grid.31880.32) Huazhong Normal university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.411407.7) (ISNI:***)

Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes.

关键词： symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent

Preparation and Reaction Mechanism of Red Mud based Ceramic Simple Bricks

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Journal of wuhan university of {2.(Materials science) 2010年第6期25卷 1001-1005页

作者：吴建锋 school of Materials science and {2. Wuhan University of Technology

In order to utilize solid wastes,ceramic simple bricks with high performances were made from industrial solid wastes such as red mud,fly ash and poor clay shale as main raw materials in this *** phase compositions and microstructures were tested by XRD,SEM and *** experimental results show that the water absorption is 45.64%,the porosity is 58.91%,bulk density is 1.2. g·cm-3,compressive strength is 54.91 MPa,bending strength is 2..52.MPa,freeze-thaw resistance is 2..2. MPa,specific heat capacity at constant pressure is 1.31 J·g-1·K-1,thermal diffusivity is 5.89×10-3 cm2.s-1,and thermal conductivity is 1.15×10-2.W·cm-1·*** effects of additives and preparation process to the properties and microstructures were discussed in *** reaction mechanism was also *** results of the reaction mechanism show that there has wollastonite and feldspar generated during the process of firing while Ca gathered around the feldspar,and then Ca would displace K and generated cacoclasite.

关键词： red mud ceramic simple bricks addictives properties and microstructures reaction mechanism

Vanadium Carbide Coating Growth on Die Steel Substrate in Borax Salt Bath

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Journal of wuhan university of {2.(Materials science) 2010年第4期25卷 600-603页

作者：王洪福 school of Materials science and Engineering Wuhan University of Technology school of Mechanical Engineering and automation North University of China

Vanadium pentoxide, borax, boron carbide and sodium fluoride were used to grow vanadium carbide coating on die steel（Cr12. Cr12.oV） surface at 950 ℃ by TD process, which extended the life period of Cr12.and Cr12.oV as punching die. Kinetics of vanadium carbide coating growth was brought forward and verified by comparison of the mathematical model with the experimental results. The thickness of coating was illustrated by SEM. The chemical constituent of coating and remnants were tested by XRD. To increase the thickness, rare earths （FeSiRe2.） were added to the borax salt bath. The electronic probe microanalysis （EPMA） revealed that the addition of rare earths could decrease carbon concentration in the coating and increase the depth of vanadium carbide coating.

关键词： vanadium carbide coating TD process punching die rare earths

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

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Journal of wuhan university of {2.(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

An Evolutionary Algorithm to Optimization of Discrete Problem Based on Pheromone

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wuhan university Journal of Natural {2.s 2001年第Z1期6卷 606-610页

作者： Huang Zhang can 1, Wu Fang cai 2. Chen Si duo 2.1.Department of Mathematics,Eastern Campus wuhan university of {2., wuhan 430070, china 2.Department of automation, Eastern Campus wuhan university of {2., wuhan 430070,china Department of Mathematics Eastern Campus Wuhan University of Technology Wuhan China Department of automation Eastern Campus Wuhan University of Technology Wuhan China

The pheromone based positive feedback approach of ant algorithm is introduced in evolutionary computation of discrete problem, so as to accomplish the optimization of each allele. It ensures stable converge of the algorithm into global optimum. The optimal cutting problem is studied as an example to analyze the performance of the algorithm. The experimental results show the novel performance of the algorithm in the optimization of discrete problem.

关键词： pheromone Ant System evolutionary computation

Poly(N-isopropylacrylamide), Poly(methacrylic acid) and Their Copolymers for Oral Colon-specific Drug Delivery

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Journal of wuhan university of {2.(Materials science) 2009年第4期24卷 571-574页

作者：高玉香 school of Chemical Engineering Wuhan University of Technology

A series of cross-linked gels of Poly（N-isopropylacrylamide） [P（NIPAAm）] and Poly（methacr-ylic acid）[P（MAA）] homopolymers and P（NIPAAm-co-MAA） random copolymers were synthesized based on NIPAAm and MAA using 4,4-Bis-（methacryloylamino） azobenzene （BMAAB） as a cross-linker. The swelling behavior of these hydrogels in different pH buffer solutions was studied. The influential factors of the gels including composition of NIPAAm and MAA, pH and temperature upon swelling behavior were investigated. The obtained gels not only hold pH and thermometrical sensitivity, but also take on enzymatic sensitivity due to the cross-linker could be degraded by enzymes of colon. Swelling equilibrium degree of copolymers was very low in acidic medium, which could avoid drug releasing due to biggish swelling of carder in stomach. Hydrogels would partly swell owing to higher pH value in small intestine. When arrived in colon, hydrogels completely swelled, meanwhile, azoenzymes located would degrade azo-bonds of polymeric network and then drug released in colon.

关键词： pH sensitivity therrnometrical sensitivity colon-specific

Dominant point detecting based non-uniform B-spline approximation for grain contour

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science china(Technological sciences) 2007年第1期50卷 90-96页

作者： ZHAO XiuYang1, YIN YanSheng1,2.& YANG Bo3 1 Shandong Key Laboratory of Engineering Ceramics, Shandong university, Jinan 2.0061, china 2.{2. of Materials, Ocean university of china, Qingdao 2.6003, china 3 State Key Laboratory of Advanced technology for Materials Synthesis and Processing, wuhan university of science and technology, wuhan 430070, china 1. Shandong Key Laboratory of Engineering Ceramics Shandong University Jinan 250061 China 2. school of Materials Ocean University of China Qingdao 266003 China 3. State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Science and Technology Wuhan 430070 China

Three-dimension reconstruction from serial sections has been used in the last decade to obtain information concerning three-dimensional microstructural ge-ometry. One of the crucial steps of three-dimension reconstruction is getting compact and fairing grain contours. Based on the achievement of closed raw con-tours of ceramic composite grains by using wavelet and level set, an adaptive method is adopted for the polygonal approximation of the digitized raw contours. Instead of setting a fixed length of support region in advance, the novel method computes the suitable length of support region for each point to find the best es-timated curvature. The dominant points are identified as the points with local maximum estimated curvatures. Periodic closed B-spline approximation is used to find the most compact B-spline grain boundary contours within the given tolerance. A flexible distance selection approach is adopted to obtain the common knot vector of serial contours consisting of less knots that contain enough degrees of freedom to guarantee the existence of a B-spline curve interpolating each contour. Finally, a B-spline surface interpolating the serial contours is generated via B-spline surface skinning.

关键词： composite B-spline dominant points control points grain contour