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

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Journal of wuhan {1. 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 {1. and Molecular {2. 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

Description of Mechanism Function about Dehydration of Cobalt Oxalate Dihydrate by Multiple Rates Isotemperature Method

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wuhan {1. Journal of Natural {2. 2004年第2期9卷 239-246页

作者： LiLi-qing ChenDong-hua collegeof{1.and{2.sciences SouthCentralUniversityforNationalitiesWuhan430074HubeiChina

A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation energyE; the pre-exponential factorA is obtained on the basis ofE andg(α). By this new method, the thermal analysis kinetics triplet of dehydration of cobalt oxalate dihydrate is determined, apparent activation energyE is 99.84 kJ·mol?1. pre-exponential factorA is 3.42.×1.9–3.872.1.9 s?1.and the most probable mechanism belongs to nucleation and growth,A m model, the range ofm is from 1.50 to 1.70. Key words multiple rates isotemperature method - isoconversional method - cobalt oxalate dihydrate - accomodation function - differential scanning calorimetry (DSC) CLC number O 636.1.Foundation item: Supported by the Key Foundation of the Science and Technology Committee of Hubei Province (2.01.BA009)Biography: Li Li-qing (1.77-), female, Master candidate, research direction: material synthesize and thermal analysis kinetics.

关键词： multiple rates isotemperature method isoconversional method cobalt oxalate dihydrate accomodation function differential scanning calorimetry (DSC)

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

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Journal of central {1. {2. of Technology 2001年第4期8卷 239-243页

作者： TANG Ke wen 1.2.,YI Jian ming 2.ZHOU Chun shan 1.ZHONG Shi an 1.(1. college of {1. and Chemical Engineering, {2. south university, Changsha 41.083, China 2. college of {1. and Chemical Engineering, Yueyang Normal university 1. college of {1. and Chemical Engineering Central South University 410083 Changsha China 2. {1. of {1. and Chemical Engineering Yueyang Normal University 414000 Yueyang China

Two new chiral stationary phases, 2.3 di O acetyl 6 O trimethylsilyl β cyclodextrin (DATBCD) and 2.6 di O trimethylsilyl 3 O acetyl β cyclodextrin(DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 41.3 and 392., the column efficiencies are respectively 3084 and 41.8, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer ( k 1. and separation factor(α)of α phenylethanol on DATBCD stationary phase are respectively 8.2. and 1.01..

关键词： capillary gas chromatography silylated and acetylated β-cyclodextrins enantiomeric separation

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan {1. Journal of Natural {2. 2002年第1期7卷 107-112页

作者： Zheng Hua 1., Du Yu-min 2.1. Department of Chemical Engineering, {1. {1. of Technology, {1. 430070, Hubei, China 2. college of chemistry and Molecular sciences, {1. {1., {1. 430072. Hubei, China wuhan {1. of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan {1. College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of central {1. {2. 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1.2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. Department of Metallurgical Science and Engineering, central {1. {2. of Technology, Changsha 41.083, China 2. college of chemistry and Chemical Engineering, Hunan {2., Changsha 1. Department of Metallurgical Science and Engineering Central South University of Technology 410083 Changsha China 2. {1. of {1. and Chemical Engineering Hunan University 410082 Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 1..32.kJ/mol because of the addition of 1. mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 1.%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion

Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1. XIAO Jie2.1. {1. of Mining, Taiyuan {1. of Technology, Taiyuan 03002., China 2. Institute of Geodesy and Geophysics, Chinese Academy of {2., wuhan 430077, China Taiyuan Univ Technol Coll Min Taiyuan 030024 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

Research on the method for retrieving soil moisture using thermal inertia model

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Science China Earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1.& ZHAO Yingshi2.1. Information {1., {1. China Agricultural {2., Guangzhou 51.642. China 2. Graduate {2. of Chinese Academy of sciences, Beijing 1.0049, China 1. Information college South China Agricultural University Guangzhou 510642 China 2. Graduate {1. of Chinese Academy of {1. Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Synthesis of todorokite by refluxing process and its primary characteristics

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Science China Earth sciences 2004年第8期47卷 760-768页

作者： FENG Xionghan1. LIU Fan1. TAN Wenfeng1. LIU Xiangwen2.& HU Hongqing1.1. {1. of Resources and Environment, Huazhong Agricultural {1., {2. 430070, China 2. Testing Center, China {1. of Geosciences, wuhan 430074, China 1. college of Resources and Environment Huazhong Agricultural University 430070 Wuhan China 2. Testing Center China University of Geosciences 430074 Wuhan China

Single phase and well-crystallined todorokite were synthesized by heating and refluxing process from birnessite as a precursor. The average chemical composition of the synthesized todorokites by refluxing for 8 h and for 2. h was Mg0.1.MnO2.1.(H2.)1.1. and in0.1.-MnO2.1.(H2.)0.88, respectively. The crystallinity of the todorokite increased and no other phase was produced with increasing refluxing period. The synthesized todorokites have the same morphologies and the similar structural characteristics with the natural todorokites and hydro-thermally synthesized samples. The chemical compositions of the synthetic tordorokites by refluxing process are close to those of todorokites synthesized by hydrothermal process, except a higher average oxidation state of Mn for the former.

关键词： todorokite,birnessite,manganese oxide,refluxing,hydrothermal,synthesis.

Pathways of birnessite formation in alkali medium

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Science China Earth sciences 2005年第9期48卷 1438-1451页

作者： FENG Xionghan1. TAN Wenfeng1. LIU Fan1. HUANG Qiaoyun1.& LIU Xiangwen2.1. {1. of Resources and Environment, Huazhong Agricultural {1., {2. 430070, China 2. Testing Center, China {1. of Geosciences, wuhan 430074, China 1. college of Resources and Environment Huazhong Agricultural University 430070 Wuhan China 2. Testing Center China University of Geosciences 430074 Wuhan China

Birnessite is a common weathering and oxidation product of manganese-bearing rocks. An O2.oxidation procedure of Mn(OH)2.in the alkali medium has been used to synthesize birnessite. Fast and powder X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), energy dispersed X-ray analysis (EDAX), infrared spectroscopy (IR) techniques and chemical composition analysis, Eh-pH equilibrium diagram approaches were employed to investigate the reaction process and pathways of birnessite formation. Results showed that the process of the birnessite formation could be divided into four stages: (1. forma- tion stage for hausmannite and feitknechtite, (2. stage of transformation of hausmannite and feitknechtite to buserite, (3) buserite crystal growing stage, and (4) stage of conversion of buser- ite into birnessite. Mn(OH)2.was mainly present as amorphous state only for a short initial time of oxidation reaction. In the oxidation process, buserite formed following two pathways by recrys- tallization after dissolution of the intermediates, and the transformations of the minerals de- pended on the Eh determined by the dissolved O2.concentration on their surfaces. The results are fundamental in further exploration on the mechanism of birnessite formation in the alkali medium. A great practical significance would also be expected with respect to the areas of mate- rial sciences.

关键词： birnessite, pathway of formation, reaction process, Eh-pH diagram, hausmannite, feitknechtite.