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SIMPLE OCKHAM ALGEBRAS

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 213-218页

作者： FANG JIE department of Mathematics, zhongshan university, guangzhou 510271,{3.. department of Mathematics Zhongshan University Guangzhou 510271 China

An algeber L is said to be simple, if its congruence lattice Con L reduces to the 2-elementchain {ω,v}. This paper describes the structure of finite simple Ockham algebras.

关键词： Ockham algebra Simple algebra Congruence lattic 2-element chain

ID-WAVELETS METHOD FOR HAMMERSTEIN INTEGRAL EQUATIONS

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Journal of Computational Mathematics 1998年第6期16卷 499-508页

作者： Xian-biao Wang Wei Lin (department of Mathematics, zhongshan university, guangzhou 5102.5,{3.) 中山大学数学系广东广州

The numerical solutions to the nonlinear integral equations of Hammerstein-type y(t) = f(t) + integral(0)(1)k(t, s)g(s, y(s))ds, t is an element of [0,1] are investigated. A degenerate kernel scheme basing on ID-wavelets combined with a new collocation-type method is presented. The Daubechies interval wavelets and their main properties are briefly mentioned. The rate of approximation solution converging to the exact solution is given. Finally we also give two numerical examples.

关键词： nonlinear integral equation interval wavelets degenerate kernel

The microbial metallogeny of weathering crust REE deposits in South china

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Chinese Science Bulletin 1999年第S2期44卷 71-73页

作者： CHEN Binghui~(1,2), WANG Zhimei~3. HUANG Limei~3. WU Fuhai~3. CHEN Jingde~2 and XU Wenlie~2 1. department of earth sciences, Nanjing {3., Nanjing 210093. china 2. department of earth sciences, zhongshan university, guangzhou 5102.5, china 3. Guangdong Pharmaceutical College, guangzhou 510244, china department of earth sciences Nanjing University Nanjing 210093 China department of earth sciences Zhongshan University Guangzhou 510275 China Guangdong Pharmaceutical College Guangzhou 510244 China

VERY little is known about the roles of microorganisms in the metallogeny of weathering crust REE deposits, although there has been much literature on REE behavior in weathering conditions. The present note deals with the microorganisms in 4 weathering profiles of an REE deposit and their roles in migration and accumulation of REE in weathering conditions. 1 Cultivation and identification of microorganisms Under strict sterilization, samples were collected from various parts of 4 weathering profiles of granites in a weathering crust REE deposit in South china. The samples were then cultivated for microorganisms with ordinary agars as culture media and then the cultivated microorganisms were dyed and identifiedunder a microscope. The sampled positions and cultivated numbers of microbial colonies are shown

关键词： microbial metallogeny weathering crust REE deposit South china.

Geochemical constraints from hydrothermal fluid inclusions of altered deformation zone type Au(Ag)deposits in Yunkai area, South china

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Chinese Science Bulletin 1999年第S2期44卷 230-232页

作者： WANG Zuwei~1, ZHANG Haihua~2, YAO Dongliang~2 and ZHOU Yongzhang~3.1. department of Geography, Tianjin Normal university, Tianjin 3.0071, china 2. {3. Institute of Geochemistry, Chinese Academy of sciences, {3. 510640, china 3. department of earth sciences, zhongshan university, guangzhou 5102.5, china eeszhou@*** department of Geography Tianjin Normal University Tianjin 300071 China guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China department of earth sciences Zhongshan University Guangzhou 510275 China

THE altered deformation zone type Au (Ag) deposits share an important part from the precious metallicore deposits in the Yunkai area, South china. Their formation is a history of poly-stage evolution. Pre- liminary source strata, Calidoniam metamorphism, Indosinian-Yanshanian ductile shear deformation andassociated hydrotheraml alteration all play certain roles in the history. This note discusses the geochemical conditional of the hydrothermal fluids during mineralization. Two representative ore deposits, the Pangxidong Ag(Au) deposit and Hetai Au deposits are selectedfor this study. They are hosted in altered ductile shear zones. Wall-rock hydrothermal alteration is bothspatially and temporally associated with the development of the ductile shear system. Silicification occurred throughout the whole alteration process. There are three groups of quartz: thepredeformational quartz, the early stage hydrothermal quartz, and the late stage hydrothermal quartz asso-

关键词： precious metallic deposit fluid inclusions mineralizing fluid South china.

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 {3., Chinese Academy of {3., Beijing 100080, china 3. department of Scientific Computing and Computer Applications, zhongshan university, guangzhou 5102.5, china) Dept. of Mathematics Beijing Jiaotong Univ. Beijing 100044 China Inst. of Mathematics Acad. of Math. and System Sci. Chinese Acad. of Sciences Beijing 100080 China Dept. of Scientific Computing Zhongshan Univ. 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

Geochemical behavior of elements at fossil sea floor water/sediment interface

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Chinese Science Bulletin 1999年第S2期44卷 232-233页

作者： ZHANG Haihua~1, XIA Yu~1, WANG Zuwei~2 and ZHOU Yongzhang~3.1. guangzhou Institute of Geochemistry, Chinese Academy of Science, guangzhou 510640, china 2. {3. of Geography, Tianjin Normal university, Tianjin 3.0071, china 3. department of earth sciences, zhongshan university, guangzhou 5102.5, china guangzhou Institute of Geochemistry Chinese Academy of Science Guangzhou 510640 China department of Geography Tianjin Normal University Tianjin 300071 China department of earth sciences Zhongshan University Guangzhou 510275 China

THIS note deals with the geochemical behavior of elements near the water/sediment interface of a fossil seafloor. The Nandan-Hechi basin, located in northwest Guangxi, Southern china, is selected for exemplified study. It is an elongated basin, and developed on a Caledonian basement. Its Devonian strata hosthydrtothermally sedimentary formations, and are typical of the intra-platformal basin facies sediments oversouthern china. A steady sedimentary sequence may be observed, commonly going from carboniferouspelite at bottom, upward through bedded chert, thickly banded argillaceous limestone, thinly bandedsiliceous limestone and small lensiod argillaceous limestone in the middle, to coarse lensoid siliceousand/or argillaceous limestone at the top. The chert and some argillaceous limestone are related to hydrothermally sedimentary origin. The present study focuses on the lensoid argillaceous limestone formation. This formation contains the following characteristic sedimentary structures: small lensoid structure,vermiform structure, wave-shaped banded structure, massive structure, white framboid structure, andcage netting structure.

关键词： water/sediment interface sedimentation periodicity sedimentary geochemistry basin.

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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Chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3.1 department of earth sciences, Nanjing {3., Nanjing 210093. china 2 guangzhou Institute of Geochemistry, Chinese Academy of sciences, guangzhou 510640, china 3.Graduate {3. of Chinese Academy of sciences, Beijing 100049, china department of earth sciences Nanjing University Nanjing China guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate university of Chinese Academy of sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

The Influence of Minimal Subgroups on the Structure of Finite Groups

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Acta Mathematica Sinica,English Series 2000年第1期16卷 63-70页

作者： Yanming Wang Mathematics department,zhongshan university,{3. 5102.5,P.R.china Mathematics department Zhongshan University Guangzhou 510275 P.R. China

Let G be a finite *** question how the properties of its minimal subgroups influence the structure of G is of considerable interest for some *** this paper we try to use c-normal condition on minimal subgroups to char... 详细信息

关键词： c-normal subgroup Supersolvable Nilpotent Generalized Fitting subgroup

Exploring effective policies for underground water management in artificial oasis: a system dynamics analysis of a case study of Yaoba Oasis

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Journal of Environmental sciences 2001年第4期13卷 476-480页

作者： XU Hong gang (earth and Environment School, zhongshan university, guangzhou 650021. ) 中山大学广东 650021

The development of oasis along the edge of the Tengerli Desert, where underground water is available, is one of the major strategies to reallocate 'ecological refuges' from their seriously degraded grasslands to agriculturally cultivable land. Yet, underground water resources, the major constraint, hate not been fully integrated in the development process. Therefore, the decline of water resources and deterioration of water quality caused by over-consumption of water resources has begun to hinder further development and has even fed to the abandonment of some oasis. A system dynamics modeling approach is applied to analyze the water use and water management structures in Yaoba Oasis as a case study. The study attempts to identify the characteristics of major feedback loops, which dominate the over-use of underground water resources leading to the deterioration of water resources in quantity and quality.

关键词： system dynamics delay underground water management oasis feedback analysis