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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

A mathematical model for solid liquid and mass transfer coupling and numerical simulation for hydraulic fracture in rock salt

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Progress in Natural Science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1,2. and ZHAO Yangsheng1(1. Mining technology institute, Taiyuan University of technology, Taiyuan 03002., china 2. Rock and Soil Mechanics institute, Chinese Academy of Sciences, wuhan 430071, china) Mining technology institute Taiyuan University of Technology Taiyuan 030024 China. Rock and Soil Mechanics institute Chinese Academy of Sciences Wuhan 43007! China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.0018t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

Multi-materials drop-on-demand inkjet technology based on pneumatic diaphragm actuator

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Science china(Technological Sciences) 2010年第6期53卷 1605-1611页

作者： XIE Dan1,2.ZHANG HongHai1,2.SHU XiaYun1,2.Xiao JunFeng1,2.& CAO Shu1,2.1institute of Micro-Systems,School of Mechanical Science and engineering,Huazhong University of Science and {2.,wuhan 430074,china 2.3} National Laboratory for Optoelectronics,wuhan 430074,china 1. institute of Micro-Systems School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

Micro-droplet jetting belongs to the field of precision fluid dispensing *** traditional subtraction manufacture process,micro-droplet jetting as an additive fabrication technique with features of non-contact and data-driven represents a new development trend of modern manufacturing *** this paper,the design,fabrication and performance of a multi-materials drop-on-demand (DOD) inkjet system based on pneumatic diaphragm actuator were *** capturing the droplet ejection process and measuring the droplet dimension,a self-made in situ imaging system based on time delayed external trigger was set *** performance of the generator was studied by adjusting the structure and control ***,the influence of fluid properties on the droplet ejection process was experimentally ***-solderballs of 160.5 μm in diameter and UV curing adhesive micro-bumps of 346.94 μm in contact diameter with the substrate were *** results demonstrated that the DOD inkjet generator possesses characteristics of robust,easy to operate and maintain,and able to withstand high temperature as well as applicability to a wide variety of materials including polymers,low melting point resin and high melting point *** system has a great potential of being used in the fields of IC and MEMS packaging,3D printing,organic semiconductor fabrication,and biological and chemical analysis.

关键词： micro-droplet jetting drop on demand pneumatic diaphragm actuator multi-materials

Exact eigenstates for a class of models describing multiphoton processes in the presence of seven bosonic modes

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 649-657页

作者： ZHAN Zhiming1,LI Weibin2.YOU Jun2.XIE Xiaotao2.& YANG Wenxing2.1.State Key Laboratory of laser technology,Huazhong University of Science and technology,wuhan 430074,china 2.Department of Physics,Huazhong University of Science and technology,wuhan 430074,china 1. State Key Laboratory of laser technology Huazhong University of Science and Technology 430074 Wuhan China 2. Department of Physics Huazhong University of Science and Technology 430074 Wuhan China

We present the analytical expressions of eigenstates and eigenenergies by using a parameter λ without the assumption of Bethe anzatz for three kinds of seven-bosonic-mode mixing models. The parameter is shown to be determined by the roots of a simple polynomial. We also demonstrate the exact analytical expressions of eigenstates and energies without any unknown parameter.

关键词： spectra, eigenstate, eigenvalue.

Structure and Magnetic Properties of Ni-doped ZnO Powder

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Journal of wuhan University of technology(Materials Science) 2010年第5期25卷 770-773页

作者：高放赵俊 Department of Electronic Science and technology 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

Optimality strategy of a sealed-offer simultaneous bargaining protocol

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Science china(Information Sciences) 2011年第1期54卷 79-90页

作者： ZHANG LinLan1,2.CHEN XueGuang2.& HONG Liu2.1School of Business,Hubei University,wuhan 430062.china 2.2. of Systems engineering,Huazhong University of Science and technology,wuhan 430074,china 1. School of Business Hubei University Wuhan 430062 China2. Institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 China

Alternating-offer bargaining protocol is the most predominant way for solving bilateral bargaining ***,alternating-offer may consume much time and cause a low effciency in some ***, a deadlock in which both negotiators are unwilling to concede or refuse to disclose more information may arise. Then mediation is *** paper presents an agent-based sealed-offer simultaneous bargaining protocol by introducing a nonbiased *** information of both agents is considered completely *** our agent-based model,both agents simultaneously submit their respective offers to the mediate *** offers of each agent are not revealed to the *** design can discourage counter-speculation and effectively control fraud and misrepresentation in a certain ***,we analyze how an agent can exploit the available information in selecting a strategy that maximizes its expected utility and give the optimal offers of each agent at each stage of the *** groups of automated experiments are conducted to evaluate the performance of the proposed automated negotiation procedure.

关键词： automated negotiation bargaining sealed-bid optimal strategy

Mechanism of Strength Loss of No-bake Phosphate Bonded Sand Mold/Core

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Journal of wuhan University of technology(Materials Science) 2009年第1期24卷 5-8页

作者：张友寿 School of Automobile engineering Wuhan University of Technology School of Mechanical engineering Hubei University of Technology

The strength loss mechanism of the phosphate bonded sand mold/core was studied. The morphology and composition of phosphate membrane on the surface of sands was analyzed with electron probe X-ray microanalyzer. Results show that magnesium causes cracks in cured phosphate membrane and results in the decrease of sand molds/cores strength. However, the addition of magne-sium significantly enhanced hygroscopy resistance of phosphate membrane. In addition, the phosphate binder added with the magnesium modifier has more rapid hardening reaction speed compared that without or with low magnesium binder. It can be concluded that the phosphate binder with the addition of magnesium modifier is favorably used in high humid and cold circumstance.

关键词： phosphate mechanism of strength loss crack hygroscopy resistance

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. institute of laser Physics and Chemistry, Sichuan University, Chengdu 610064,{2. 2. Department of Physics, Luoyang Normal College, Luoyang 47102.,{2. 3. State Key Laboratory of laser technology, Huazhong University of Science and technology, wuhan 430074,{2. Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 1. institute of laser Physics and Chemistry Sichuan University 610064 Chengdu China 2. State Key Laboratory of laser technology Huazhong University of Science and Technology 430074 Wuhan China 3. Department of Physics Luoyang Normal College 471022 Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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Earthquake engineering and engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1,Hou Longqing2.Xu Hongmei2.and Yuan Xiaoming1 1. institute of engineering Mechanics,{2. Earthquake Administration,Harbin 150080,{2. 2. East china institute of technology,Fuzhou 344000,{2. institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in china is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (118) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1) sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,12. villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; (2. the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 541 m according to the geological cross sections; (3) there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from 2. km to 40 km in length,and about ten gravelly soil liquefied sites distributed within Mianyang area; and (4) the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake