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Science China Chemistry 2002年第5期45卷 541-550页

作者：高世扬朱黎霞郝志显夏树屏 Xi'anBranch InsituteofSaltLakesChineseAcademyofSciencesXi'an710043China

The crystallization processes of hydrated Mg-borates, boric, magnesium hydroxide and Mg-oxychloride from MgO-B2O3-18%MgCl2-H2O supersaturated solution at 20℃ have been studied by kinetic method. The crystallization solid phases were characterized by X-ray powder diffraction, IR spectra, thermal analysis and chemical analysis. The liquid-solid phase diagram of ther-modynamic nonequilibrium state has been given. In this phase diagram, there exist eight crystallization fields, boric acid(H3BO3), trigomagneborite(MgO·3B2O3·7.5H2O, MgO·3B2O3·7H2O), hungchaoite(MgO·2B2O3·9H2O), inderite(2MgO·3B2O3·15H2O), chloropinnoite(2MgO·2B2O3·MgCI2·14H2O), magnesium hydroxide(Mg(OH)2) and magnesium oxychloride (5Mg(OH)2·MgCI2·8H2O).

关键词： crystallization kinetic, thermodynamic nonequilibrium, phase diagram, Mg-borate.

Time-Temperature-Transformation (TTT) diagram of Epoxy-terminated Poly(Phenylene ether ketone)

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河北工业大学学报 1997年第A1期26卷 81-91页

作者： Wang Qiang Cao Fengkun(Department of Chemical Engineering, Hebei University of TechnologyTianjin 300130, P.R.China)He Tianbai(Polymer Physics Laboratory, Changchun Institute of Applied ChemisedChinese Academy of Sciences, Changchun 130022)

Time-temperature-transformation diagram for epoxy-terminated poly(phenylene ether ketone) and 4, 4*-diaminodiphenyl sulfone was studied using a differential scanning calorimeter, thermal grametry analyzer and a cone-and-plate rheometer. Based on a predicting model proposed here, which is used for determining the times to vitrification (tvit), and only few experimental results from DSC, T’GA and cone-and-plate rileometer, TTT diagram can be easily determined.

关键词： TTT diagram, predicting model epoxy PEK

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. College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China 2. Testing Center, China University of Geosciences, Wuhan 430074, China College of Resources and Environment Huazhong Agricultural University Wuhan China Testing Center China University of Geosciences 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.

Experimental studies on pathway patterns of secondary oil migration

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Science China Earth Sciences 2004年第Z2期47卷 190-198页

作者： HOU Ping ZHOU Bo LUO Xiaorong Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The oil migration patterns in porous medium are discussed based on the results of diphasic expulsing experiments. In the experiments, dyed kerosene was used as expulsing phase to expulse water saturated in a glass cylinder filled with sorted glass beads. Two series of experiments were done: one with different initial oil column heights and the other with variable oil injection rates. Three secondary migration patterns, including stable displacement pattern, fin-gering pattern and stringing pattern may be recognized in each series of experiments. Two clas-sic dimensionless parameters, the modified Bond number and the Capillary number, were used to construct a phase diagram that may characterize the patterns. A new method was proposed to calculate the Darcian velocity of moving kerosene in the cylinder when only buoyancy force acts. It is found that when Darcian velocity is used to get the two dimensionless parameters, the data from both series of experiments, as well as those obtained from literatures, may be reasonably drawn in a phase diagram to identify the three migration patterns.

关键词： secondary migration, migration patterns, phase diagram, simulation experiments, Darcian velocity.