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Experimental study of ore gabbro liquid immiscibility

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Science china Earth sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2. XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4.1. Guangzhou institute of Geochemistry,{2., Guangzhou 51064., china 2. Wuhan University, Wuhan 4.0072. china 3. institute of Geology, china Seismological Bureau, Beijing 10002., china 4. Faculty of Earth sciences, china University of Geosciences, Wuhan 4.0074. china 1. Guangzhou institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan University 430072 Wuhan China 3. institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 12.0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3 1. institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan {2.0077, china 2. Graduate School of the chinese academy of sciences, Beijing 100039, china 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 2.0030, china 1. institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

^(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 5106{2., china institute of Geology, chinese academy of sciences , Beijing 10002., china South china institute of botany, chinese academy of sciences, Guangzhou 510650, china Guannzhou institute of Geochemisry Chinese Academy of Sciences Guanazhou China institute of Geology Chinese Academy of Sciences Beijing China South china institute of {2. Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14. values of these profiles decrease with increasing of depth. The Δ14. values in 30—4. cm depth int... 详细信息

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14./sup>C values of these profiles decrease with increasing of depth. The Δ14./sup>C values in 30—4. 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 14./sup>C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 4.5 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14./sup>C" in Qingyunsi and Wukesong profiles are 10 and 2. cm, respectively.

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

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State Key Laboratory of Lithospheric Evolution, institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. 2. Graduate School of chinese academy of sciences, Beijing 100039,{2.) [a]State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4.91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 6100{2., Sichuan, china 2. Graduate University of chinese academy of sciences, Beijing 1000{2., china 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China institute of Geographical sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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Science china(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2. ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3 & QIU YinLong4.1 State Key Laboratory of Systematic and Evolutionary botany, {2. of botany, chinese academy of sciences, Beijing {4., china 2.Graduate University of chinese academy of sciences, Beijing 100039, china 3 South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china 4.Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 4.109-104., USA State Key Laboratory of Systematic Evolutionary botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Graduate University of chinese academy of sciences Beijing 100039 China South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Department of Ecology Evolutionary Biology University of Michigan Ann Arbor MI 48109-1048 USA

Tectariaceae are a pantropical fern family of about 2. genera, among which 8 are distributed in china. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in china were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2.& ZHANG Na1 1. institute of Engineering Thermophysics, chinese academy of sciences, Beijing 100080,{2. 2. Graduate School, chinese academy of sciences, Beijing 100080,{2. 1. institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School Chinese Academy of Sciences 10080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

High Throughput SNP Genotyping with Two Mini-sequencing Assays

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 379-384页

作者： Chunqing LUO1,2., Libin DENG1#, and Changqing ZENG1,2. The institute of Genetic and Developmental Biology, the chinese academy of sciences, Beijing 100101,{2. 2.eijing Genomics institute, the chinese academy of sciences, Beijing 101300,{2. The institute of Genetic and Developmental Biology the Chinese Academy of SciencesBeijing 100101 China Beijing Genomics institute the Chinese Academy of SciencesBeijing 101300 China

Two mini-sequencing methods, FP-TDI (template-directed dye-terminator incorporation with fluorescence-polarization) and MassArray (matrix assisted laser desorption ionization time of flight detection mass spectrometry), were optimized. A numeric standard was introduced to evaluate the SNP scoring quality of FP-TDI assay, thus made the optimization work easier. At the same time, using multi-PCR technology, 8-plex genotyping of MassArray assay was successfully carried out, some softwares were developed and the data process of MassArray was highly automated. Then these two methods were applied to high throughput SNP genotyping, the accuracy, efficiency and robustness were compared. The result shows FP-TDI is more sensitive to the concentration of SNPprimer and PCR product, as well as extension cycles, the SNPprimer length of FP-TDI should be 2.0}30 bp long, whereas MassArray assay prefers to be as short as only 16 *** 64.0 SNP sites of human chromosome 3 were genotyped in a sample of 90 individuals, 4.92.sites by FP-TDI assay and 164. sites by MassArray assay, the success rates of FP-TDI and MassArray were 67.7% and 93.6% respectively. The throughput of MassArray was higher than FP-TDI, and the cost of MassArray was lower, MassArray was more suitable for high throughput SNP genotyping.

关键词： SNP genotyping FP-TDI MassArray high throughput

Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent

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Science china Chemistry 2006年第4期49卷 363-370页

作者： LI Xiaobin1,2. CAO Hongbin1 & ZHANG Yi1 1. institute of Process Engineering, chinese academy of sciences, Beijing 100080,{2. 2. Graduate School of the chinese academy of sciences, Beijing 100039,{2. 1. institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 4..0 kg/m3 to 2..4.kg/m3 with the increase of water level from 3 pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 2.0} μm to 356 μm with the increase of water level from 3 pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2.out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent.

关键词： polyether polyol, polyurethane rigid foam, compressive strength, dimensional stability, cell size, glass transition temperature.