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Arrangement models of alkylammonium cations in the interlayer of HDTMA^+pillared montmorillonites

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chinese Science Bulletin 2003年第4期48卷 368-372页

作者： ZHU Jianxi, HE Hongping, GUO Jiugao, YANG Dan & XIE Xiande guangzhou Institute of geochemistry, chinese academy of sciences,{3., china Correspondence should be addressed to He Hongping guangzhou Institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The orientation of HDTMA+ in the interlayer of organic pillared montmorillonites prepared at different concentrations of HDTMA+ have been studied using X-ray powder diffraction (XRD) and theoretical calculation. A series of arrangement models of HDTMA+ in the interlayer of montmorillonite have been proposed as lateral-monolayer (LM), lateral-bilayer (LB), pseudotrilayer (PT), paraf-fin-type-monolayer (PM), paraffin-type-bilayer (PB). With the increase of the concentration of HDTMA+, the arrange-ment model of HDTMA+ in the interlayer of montmorillo-nites changes as lateral-monolayer→lateral-bilayer→para- ffin-type monolayer→pseudotrilayer→paraffin-type-bilayer and the packing density of HDTMA+ in the interlayer in-creases gradually. In the intermediate stages, different mod-els may coexist.

关键词：有机柱形蒙脱土粘土夹层 HDTMA^+ 烷基铵离子排列模式

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2, LIU Yu2 & TAN Ming3.. South china Sea Institute of Oceanology, chinese academy of sciences. guangzhou 5103.1, china 2. State Key Laboratory of Loess and Quaternary Geology, Earth Environmental Institute, chinese academy of sciences, Xi’an 710075, china 3. Institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Some properties on multivariate filter banks with a matrix factorization

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Progress in Natural Science:Materials International 2005年第2期15卷 20-30页

作者： LIAN Qiaofang1, XIAO Hongying2* and CHEN Qiuhui3.1. Department of Mathematics, Beijing Jiaotong University, Beijing 100044, china 2. Institute of Mathematics, academy of Mathematics and System sciences,{3., Beijing 100080, china 3. Department of Scientific Computing and Computer Applications, Zhongshan University, guangzhou 510275, china) Department of Mathematics Beijing Jiaotong University Beijing 100044 China. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China. Department of Scientific Computing and Computer Applications Zhongshan University Guangzhou 510275 China

A class of multivariate filter banks with a matrix factorization has been developed by Chen et al. The main purpose of this paper is to discuss some further properties of this kind of filter bank, such as the completeness, accuracy of the corresponding scaling functions and the relationships with Daubechies' wavelets and the multi-wavelets provided by Chui and Lian. Moreover, some examples are given to show that this kind of filter bank has a higher accuracy for the scaling functions.

关键词： filter banks completeness accuracy matrix factorization

^(14)C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi guangzhou Institute of Geochemisry, chinese academy of sciences, guangzhou 510640,{3. Institute of Geology, chinese academy of sciences , Beijing 100029,{3. South{3. Institute of Botany, chinese academy of sciences, guangzhou 510650,{3. Guannzhou Institute of Geochemisry Chinese Academy of Sciences Guanazhou China Institute of Geology Chinese Academy of Sciences Beijing China South china Institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 3.—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 425 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14C tracing 14C apparent age.

Subsolidus phase relations in the system MgO-ZnO-SiO_2 at high pressure

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chinese Science Bulletin 1999年第12期44卷 1146-1149页

作者： LI Jianping, Jacques Kornprobst Didier Laporte guangzhou Institute of geochemistry , chinese academy of sciences ,{3., china Departement des sciences de la Terre, University Blasie Pascal, 63.03. Clermont-Ferrand, France guangzhou Institute of geochemistry Chinese Academy of Sciences Guangzhou China Département des sciences de la Terre Université Blasie Pascal Clermont-Ferrand France

The subsolidus phase relations were determined experimentally in the system MgO-ZnO-SiO2 at 1.0 GPa and 1 200℃, by use of the high-pressure apparatus "piston-cylinder". The results showed characteristics of the phases assemblage different from that in similar ternary systems. It is impossible to form complete Mg2SiO4-Zn2SiO4 olivine and Mg2Si2O6-Zn2Si2O6 pyroxene solid solution. This is controlled by the properties of Zn2+ with an outer layer of electron (Ar)3.10, different from others transition metal ions, like Fe2+ , Ni2+ , Co2+ .

关键词： high pressure MgO-ZnO-SiO2 system subsolidus phase relation.

Analytical method of radiation by a wave energy device with dual rectangular floating bodies

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Acta Oceanologica Sinica 2010年第3期29卷 106-115页

作者： WANG Wensheng YOU Yage ZHANG Yunqiu WU Bijun YE Yin guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Renewable Energy and Gas Hydrate Chinese Academy Sciences Guangzhou 510640 China Graduate University Chinese Academy of Sciences Beijing 100049 China

The system with one floating rectangular body on the free surface and one submerged rectangular body has been applied to a wave energy conversion device in water of finite depth. The radiation problem by this device on a plane incident wave is solved by the use of an eigenfunction expansion method, and a new analytical expression for the radiation velocity potential is obtained. The wave excitation force is calculated via the known incident wave potential and the radiation potential with a theorem of Haskind employed. To verify the correctness of this method, an example is computed respectively through the bound element method and analytical method. Results show that two numerical methods. are in good agreement, which shows that the present method is applicable. In addition, the trends of hydrodynamic coefficients and wave force are analyzed under different conditions by use of the present analytical method.

关键词： wave energy device hydrodynamic coefficients wave force analytical method

Evaluation criteria for gas source rocks of marine carbonate in china

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Progress in Natural Science:Materials International 2005年第9期15卷 810-817页

作者： WANG Zhaoyun1**, ZHAO Wenzhi1 and WANG Yunpeng2(1. Research Institute of Petroleum Exploration & Development,Petrochina, Beijing 100083. china 2. guangzhou Institute of {3., chinese academy of sciences, guangzhou 510640, china) Research Institute of Petroleum Exploration & Development PetroChina Beijing 100083 China. guangzhou Institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Hydrocarbon generating and expulsion simulation experiments are carried out using samples artifically matched between the acid-dissolved residue of relatively low-maturity limestone and the original sample. This work makes up for the insufficiency of source rock samples with high abundance of organic matters and low maturity in china. The organic carbon content of the 10 prepared samples varies between 0.15% and 0.74%. Pyrolysis data and simulation experiment results of hydrocarbon generating and expulsion, which were obtained by a high-temperature and high-pressure open system, indicate that the lower limit of organic carbon content for marine carbonate rock to generate and expel hydrocarbons is 0.23.—0.3.%. In combination with the numerical analysis of organic carbon in marine carbonate rocks from Tarim Basin, Sichuan Basin, Ordos Basin and North china, as well as the contribution of these gas source rocks to the discovered gas pools, we think that the organic carbon criterion for carbonate gas source rocks should be 0.3..

关键词： carbonate gas source rock gas-generating efficiency evaluation criteria simulation experiment.

TWO TYPES OF CENOZOIC HIGH-K MAGMATINSM IN EASTERN TIBET:IMPLICATIONS FOR THE NATURE OF MANTLE SOURCES

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地学前缘 2000年第S1期7卷 295-296页

作者： Wang Jianghai, Xie Guanghong[WT5,5”BX](guangzhou Institute of geochemistry, chinese academy of sciences, Wushan,{3., china)

Cenozoic high\|K igneous rocks are widely distributed in eastern Tibet. These rocks are exposed as flows, dykes and small intrusions along a narrow north\|south trending zone, which follows Tertiary fold belts and the Batang—Lijiang and Ailao Shan—Red River strike\|slip systems. Although several models were proposed to interpret their petrogenesis (Deng, 1989; Arnaud et al., 1991; Turner et al., 1996; Yin et al., 1995; Miller et al., 1999), their origin still remains hotly debated. Moreover, the published results were only focused on the high\|K igneous rocks resulted from partial melting of an enriched lithospheric mantle. Here, we present the detailed documents to testify the existence of a new kind of high\|K igneous rocks in eastern *** new 3. Ar/ 40 Ar age data (Wang et al., 1999) and published age data for high\|K rocks in eastern Tibet show two distinctive magmatic episodes: one between 42Ma and 24Ma, and the other since ca.16Ma. They correspond to two types of high\|K magmatism in eastern Tibet. We name the older and younger groups as types Ⅰ and Ⅱ, respectively.

关键词： Cenozoic high\|K magmatism enriched and depleted mantle sour ce Pb\|Sr\|Nd isotopes transpressional and transtensional tectonics Eastern T ibet

NaAlSi_3._8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

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chinese Science Bulletin 2001年第13期46卷 1121-1126页

作者： XIE Xiande, CHEN Ming, WANG Deqiang & El Goresy A.1.guangzhou Institute of geochemistry, chinese academy of sciences,{3., china 2. Max-Planck-Institute fur Chemie, 55128 Mainz, Germany guangzhou Institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China Max-Planck-Institute für Chemie 55128 Mainz Germany

The Suizhou L6 chondrite contains a few very thin shock melt veins of 0.02-0.09 mm in width. In spite of small width of the veins, shock-induced high-pressure phases, such as coarse-grained NaAlSi3.8-hollandite, ringwoodite, majorite and fine-grained matrix majorite-pyropess have been discovered in these veins. NaAlSi3.8-hollandite, the high-pressure phase of plagioclase, in Suizhou shock veins occurs as a single phase mineral, no silicate glassy phase, such as albitic glass, was incorporated with it. The presence of above-mentioned high-pressure phases constrains the high pressure (up to 23.24 GPa) and high temperature (up to 1900-2000℃) regime in Suizhou shock veins, and indicates that the duration of high-pressure regime in the veins should be long enough (a few seconds) for phase transformation and crystallization of minerals under pressure. The discovery of the first natural single-phase crystalline NaAlSi3.8- holland-ite in Suizhou meteorite is of important significance in understanding the Earth’

关键词： high NaAlSi3.8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite