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Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. china university of Geosciences,{2., china 2. Institute of Geology, chinese Academy of Sciences, beijing 10002., china 1. china university of Geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2. nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china Agricultural university,{2., china 2. Institute of Physics, chinese Academy of Sciences, beijing 100080, china 1. College of Science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

In situ reproductive organs of Early Cretaceous ferns from Northeast china

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chinese Science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and CHEN Fen1. Research Institute of Petroleum and Development, beijing 100083 2. china {2. of Geosciences, beijing 100083, china Research Institute of Petroleum and Development Beijing china university of Geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of Northeast china, whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and Heilongjiang of Northeast china. The study focuses on 35 species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： Northeast china Early Cretaceous Filicopsida in situ reproductive organs.

The features of gravity field and deep structure in western part of the South Yellow Sea

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chinese Science Bulletin 2000年第8期45卷 759-764页

作者： WANG Qianshen1 & AN Yulin1. Institute of Geophysics, chinese Academy of Sciences, beijing 100101,{2. 2. chinese university of Geology, beijing 100083,{2. Institute of Geophysics Chinesc Academy of Sciences Beijing China chinese university of Geology Beijing China

The gravity data from the sea region to the west of 12.° E of the South Yellow Sea have been processed and the feature of gravity fields analyzed. An experience relationship formula on the filter wavelength and corresponding depth has been put forward. Combined with the geological and seismic data, the deep tectonic framework and structural characters as well as possible favourable prospecting district for hydrocarbon in the South Yellow Sea have been discussed and analyzed.

关键词： western part of the South Yellow Sea gravity field deep structure.

On some tests-based projection pursuit for elliptical symmetry of a high-dimensional distribution

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chinese Science Bulletin 1998年第6期43卷 450-458页

作者： JING Ping 1 and ZHU Lixing 2.1. Mathematics Lab, china university of Mining & Technology,{2., china 2. Probability Lab, Institute of Applied Mathematics, chinese Academy of Sciences, beijing 100080, china Mathematics Lab China University of Mining & Technology Beijing China Probability Lab Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Some test statistics of Kolmogorov type and Cramér-von Mises type based on projection pursuit technique are proposed for the testing problem of sphericity of a high-dimensional distribution. The limiting distributions of the test statistics are derived under the null hypothesis and under any fixed alternative. The asymptotic properties of bootstrap approximation are investigated. Furthermore, for computational reasons, an approximation for the statistics, based on the number theoretic method, is suggested.

关键词： bootstrap approximation projection pursuit type statistic elliptical symmetry.

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Science china Earth Sciences 2004年第10期47卷 896-911页

作者： ZHANG Changhou1,2. WU Ganguo1,2. WANG Genhou2. ZHANG Weijie2.& SONG Honglin2.1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology, china university of Geosciences, Ministry of Education of china, beijing 100083, china 2. School of Earth Sciences and Mineral Resources, china university of Geosciences, beijing 100083, china 1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology China University of Geosciences Ministry of Education of China 100083 Beijing China 2. School of Earth Sciences and Mineral Resources China University of Geosciences 100083 Beijing China

The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults, strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation re- spectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt. The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement struc- tures might be taken as one of the mechanisms of intraplate deformation and orogeny.

关键词： Yanshan Orogenic Belt, northwest extending tectonic complex, thrust system, geochronology.

On three-dimensional geological modeling and visualization

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Science china Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. Department of Resource Exploitation Engineering, china university of Mining and Technology,{2., china 2. beijing Institute of Petrochemical Technology, beijing 102.17, china 1. Department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing Institute of Petrochemical Technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

Research progress in the inner surface modification of metal tubes by plasma processing

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Progress in Natural Science:Materials International 2006年第11期16卷 1119-1126页

作者： ZHANG Guling~ 1,2.**, WU Xingfang~1, GU Weichao~2. CHEN Guangliang~2. FENG Wenran~2. NIU Erwu~2. LI Li~2. L Guohua~2. CHEN Huan~2. FAN Songhua~2. LIU Chizi~2.and YANG Size~2.1. School of Material Science and Engineering, university of Science and Technology beijing,{2., china 2. beijing National Laboratory for Condensed Matter Physics, Institute of Physics, chinese Academy of Sciences, beijing 100080, china) School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The recent progress in inner surface hardening of tubes by plasma processing is summerized. Several techniques of inner surface plasma source ion implantation and deposition are introduced, and their advantages and disadvantages are discussed. The basic principles, technical features and new progress of inner surface plasma source ion implantation methods for metal tubes, which were developed in our laboratory, are described in detail. And perspectives of the future technical development for inner surface ion implantation of tubes are presented.

关键词： PSII metal tubes inner surface surface modification.

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 College, South china Agricultural university, Guangzhou 510642. china 2. Graduate university of chinese Academy of Sciences, beijing 100049, china 1. Information College South China Agricultural University Guangzhou 510642 China 2. Graduate university of chinese Academy of Sciences 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.