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Synthesis and characterization of Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-σ)

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Rare Metals 2009年第1期28卷 39-42页

作者： WANG Qibao YUAN Yan HAN Minfang ZHU Peiyu School of Chemical and Environmental Engineering China University of Mining and Technology （Beijing） Beijing 100083 China

Perovskite-type Ba0.5Sr0.5Co0.8Fe0.2O3-σ （BSCFO） powders were synthesized using two methods, solid-state reaction （SSR） method and citrate-EDTA complexing method （CC-EDTA）. Then the powders were pressed to green disks of 19 nun in diameter and sintered at 1140℃ for 5 h. The shrinkage rate and relative density of the membranes prepared from the perovskite-type powders were determined and calculated, and the powders and derived membranes were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The resuits show that the shrinkage rates of the two kinds of disks are nearly the same （about 10%）. The disks prepared by the SSR method had a bigger grain size and lower relative density than those prepared by the CC-EDTA method. The conductivity of the membranes prepared by the SSR method was about 38 S/cm, higher than that of the membranes prepared by the CC-EDTA method, which was about 30 S/cm, at the same temperature of600℃.

关键词： perovskite-type oxides oxide membrane solid-state reaction complexing method physical properties

THE ACTION AND SIGNIFICANCE OF LOW ORGANISM IN THE FORMATION OF HIGH-SULFUR COAL

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Scientia Geologica Sinica 2000年第3期 339-352页

作者： Shifeng Dai (beijing Campus, china university of mining and technology, beijing 100083)

This paper describes the coal petrological characteristics and the action and significance of low organism during the high sulfur coal formation in the Wuda coalfield, Inner Mongolia, Northern china. Petrological and geochemical studies show that No.9 coal seam, formed in tidal delta plain setting, not only have a high content of desomocollinite (up to 64.7%) that indicates a strong gelafication and bacteria activity during coal accumulation, but also have the highest sulfur content (3.46%) because of seawater influences. The values of both organic and pyritic sulfur isotopes (from -12.3* to 5.8* and from -18.7* to 1.1* respectively) in Wuda coals are more variable and generally tend to be more negative in high-sulfur coals, which indicates the heavy microbiological isotopic fractionation and a large portion of sulfur in high-sulfur coals originating from bacteriogenic sulfide. Findings of pyrilized rod-like bacteria, cyanophyte’s gelationoous sheath and degraded algae organic matter suggest that bacteria and algae play an important role in the formation of the high-sulfur coal. The characteristics of spectra, Fe+ and its associated inorganic elements ions of the No.9 coal seam were studied by using the high-resolution Time of Flight Secondary Ion Mass Spectrometer (TOF-SIMS). Besides Fe+ ( 54Fe+, 56Fe+, 57Fe+ ), other associated inorganic ions, such as 27Al+, 28Si+, 29Si+, 30Si+, 40Ca+, 63Cu+, 65Cu+, 64Zn+, 66Zn+, 67Zn+, 68Zn+, 58Ni+, 60Ni+, and 62Ni+ were detected. The results show that the bacteria play an important role in the medium change, migration and activation and enrichment of Cu and Zn in the formation of pyrilized rod-like bacteria.

关键词： SIMS TOF THE ACTION AND SIGNIFICANCE OF LOW ORGANISM IN THE FORMATION OF HIGH-SULFUR COAL ACTION high

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3 1. School of Surveying and Landing Information Engineering, Henan Polytechnic university, Jiaozuo 454003, china 2. College of Geoscience and Surveying Engineering, china university of mining and technology, beijing 100083, china 3. Surveying and Mapping Press, beijing 100045, china [a] School of Surveying and Landing Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] College of Geoscience and Surveying Engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

EXPERIMENTAL STUDY AND NUMERICAL SIMULATION OF FLUORIDE IN SAND

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Journal of Hydrodynamics 2006年第6期18卷 748-751页

作者： ZHANG Hong-mei SU Bao-yu School of Resources and Safety Engineering China University of Mining and Technology Beijing 100083China College Of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098China

The transport and transformation of fluoride in sand were studied by using soil tank test under the condition of saturated water in this article. Based on the analysis of the laboratory experiments, the rules of fluorine transportation and transformation were simulated in sand by solving the advection-diffusion equation. Through comparison between computed results and observed data , it is shown that the established model and determined parameters could be used to simulate the fluoride transport in sand.

关键词： sand fluoride dynamic test numerical simulation

Connectivity of the Mandelbrot set for the family of renormalization transformations

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Science china Mathematics 2010年第3期53卷 849-862页

作者： WANG XiaoGuang 1,QIU WeiYuan 1 , YIN YongCheng 1 , QIAO JianYong 2 & GAO JunYang 2 1 School of Mathematical Sciences, Fudan university, Shanghai 200433, china 2 Center of Mathematics, china university of mining and technology, beijing 100083, china 1. School of Mathematical Sciences Fudan University Shanghai 200433 China2. Center of Mathematics China University of Mining and Technology Beijing 100083 China

We show that the Mandelbrot set for the family of renormalization transformations of 2-dimensional diamond-like hierachical Potts models in statistical mechanics is connected. We also give an upper bound for the Hausd... 详细信息

关键词： connectivity Mandelbrot set renormalization transformations

Resistance to chemical attack of bittern-resisting cement in high-bittern environment

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International Journal of Minerals,Metallurgy and Materials 2005年第5期 87-93页

作者： Yunbing Hou, Bingwen Wang, Yu Chen, Botao Zhang, and Lin Yu School of Resource & Safety Engineering, china university of mining & technology (beijing), beijing 100083, china

A new kind of bittern-resisting cement (BRC) was introduced. This material is based on the ternary cementitious system of clinker containing C4A3 S phase, high-activity ground granulated blast-furnace slag (GGBFS) and fly ash (FA). The hydration proc- ess and the hydrated products of BRC were studied by means of XRD, TG-DTA and SEM, and the resistance to chemical attack of BRC in high-bittern environment was also examined. The corrosion experiment in seven kinds of brines proved that BRC exhibits an excellent resistance to chemical attack of bittern. The corrosion resistance factors were calculated and all of them were greater than 0.96. It showed that BRC totally controls the cement-based material corrosion in brines from four aspects: (1) making full use of the dominant complementation effect of mineral materials; (2) diminishing the hydrated products easy to be attacked; (3) improving the microstructure of hardened cement mortar; (4) degrading the chemical attack of bittern.

关键词： bittern-resisting cement ternary cementitious system high-activity mineral materials resistance to chemical attack bit- tern corrosion resistance factor corrosion mechanism

CHARACTERISTICS AND ORIGIN MODEL OF KAOLINITE ROCKS IN LATE-PALAEOZOIC COAL MEASURES, NORTH china

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Scientia Geologica Sinica 2000年第1期 91-96页

作者： Liu Qinfu( china university of mining and technology beijing 100083 )Sun Qingfeng (Northwest Normal university, Lanzhou 730070) Yang Xiaojie (china university of mining and technology beijing 100083)

The kaolinite rocks (including tonstein, flint clay and soft kaolin clay) are very abundant in the Late-Palaeozoic coal measures of North china The content of kaolinite minerals are in general more than 80% and up to 90%~ 100% in many good quality rocks. The accessory minerals include l/S mixed-layer clay mineral, NH4-illite, boemite, diaspore, chlorite, quartz,feldspar, feldspar, zircon, tourmaline and arutile. The Hinkley index (HI) varies with different kinds and origin of kaolinite, being the highest for the soft kaolin clay and the lowest for the terrigenous kaolinite. Geochemical studies show that the mother rocks are mainly related to the acid rocks. Three models of origin for the various types of kaolinite rocks were put forward in this paper.

关键词： CHARACTERISTICS AND ORIGIN MODEL OF KAOLINITE ROCKS IN LATE-PALAEOZOIC COAL MEASURES NORTH china rock NH REE

ROLE OF ORGANIC MATTER IN THE FORMATION OF KAOLINITE ROCKS OF LATE-PALAEOZOIC COAL MEASURES, NORTH china

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Scientia Geologica Sinica 2000年第3期 333-338页

作者： Liu Qinfu (china university of mining and technology, beijing , 100083) Sun Qingfeng (Northwest Normal university, Lanzhou, 730070) Zhang Pengfei (china university of mining and technology, beijing , 100083)

Organic matter and organic acid are rich in kaolinite rocks in coal measures. Terrestrial plant debris, amorphous organic matter, fulvic acid (FA) in the soft kaolin clay associated with weathered coals and ultramicro-organisms and their burrows are identified in kaolinite rocks in Late-Palaeozoic coal measures of North china. Modeling experiment by using organic acid reacted with aluminosilicate minerals shows that fulvic acid has a great ability to dissolve the aluminosilicate minerals and to accelerate the transformation and crystallization of kaolinite. The author suggests that organic matter and organic acid play an important role in the formation of kaolinite rocks in coal measures.

关键词： ROLE OF ORGANIC MATTER IN THE FORMATION OF KAOLINITE ROCKS OF LATE-PALAEOZOIC COAL MEASURES NORTH china rock acid

Resources of Kaolinite Rocks in china Coal Measures

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Journal of Earth Science 2000年第2期19卷 62-65页

作者： Liu Qinfu Department of Resources Engineering, china university of mining and technology, beijing 100083 Xu Hongliang Material Department, Zhengzhou university of technology, Henan 450002

The proved reserve of kaolinite rocks in china coal measures is about 1.673 billion tons. The types of kaolinite rocks contain tonstein, flintclay and soft kaolin. Their origin modes include alteration of volcanic ash, terrigenous clay deposit and weathering of coal and adjacent rocks. The organic matter and organic acid play an important role in the formation of kaolinite rocks of coal measures. The difference in properties between kaolinite rock and traditional kaolin requires different processing technologies.

关键词： coal measures kaolinite rocks reserve origin.