华北地台太古代高级变质地体中的金矿化

很多人认为太古代地体中没有绿岩带就不可能有金矿化,但华北地台上一些高级变质地体中也发现了一系列大中型金矿.本文讨论了高级变质地体中产生金矿化的可能性,初步总结了此类金矿的成矿地质特征,并将其与典型绿岩带型金矿进行了对化,发现了它们之间存在一系列区别。本文并对产生之些区别的原因进行了初步探讨。     

华北地台东部花岗岩容矿型金矿床的时空演化

华北地台东部分布有众多的花岗岩型金矿床,按照岩体与矿化的时间关系可分为同侵入岩型及后侵入岩型两类。前者主要分布在冀、辽接壤地区,成岩与成矿时代相近,为中侏罗世;后者主要分布在辽宁及山东等地,成矿比成岩要晚20－120Ma以上,成岩时代主要为侏罗纪,成矿时代为白垩纪。NWW向SEE方向金矿化时代变新,可能显示出中生代太平洋板块使华北地台活化的作用向东迁移并对金矿床形成了控制作用,同时在华北地台北缘从南向北矿化变新也显示出西伯利亚板块在中生代时期对华北地台造成的影响。     

川西泸定—康定地区变质火岩岩的岩石化学初步研究

首次发现玄武质科马提岩夹层，以Ⅱａ型为主，少量样品属Ⅲ型。英安岩的稀土配分特征与绿岩带中的Ｆ１型一致，少量为Ｆ２型。该套变质火山岩可能是绿岩带的残块，与康定片麻岩一起构成晚太古代花岗－绿岩地体，东北延可达川北、秦巴、鄂西等地。     

夹皮沟片麻岩岩石化学特征及其地质意义

赋存了夹皮沟金矿区绝大部分金矿的夹皮沟片麻岩主要由ＴＴＧ质斜长片麻岩及其中拉斑玄武岩质暗色包体组成，岩石化学上呈双峰特征和奥长花岗岩系列演化趋势，ＲＥＥ组成上均显示了较大的Ｅｕ正异常，δＥｕ最高可达４．６，相似于西格陵兰等典型太古代高级变质地体中的双峰式片麻岩，与裂谷型太古代绿岩带中的双峰式钙碱性火山岩有着本质的不同．     

川西泸定─康定地区变质火山岩的岩石化学初步研究

首次发现玄武质科马提岩夹层，以Ⅱ＿ａ型为主，少量样品属Ⅲ型。英安岩的稀土配分特征与绿岩带中的Ｆ＿１型一致，少量为Ｆ＿２型。该套变质火山岩可能是绿岩带的残块，与康定片麻岩一起构成晚太古代花岗─绿岩地体，东北延可达川北、秦巴、鄂西等地。     

浅谈华北绿岩型金矿矿床地质特征

绿岩型金矿是世界上同时也是我国最重要的金矿床类型,是指产在花岗岩—绿岩地体背景下的金矿床类型,其控矿构造形式主要有：韧脆性剪切叠加构造岩带控矿,断裂复合—叠加接触带构造岩控和脆性剪切裂隙控矿三种。按其矿体形态规模和内部组构特征,可将矿体划分为石英脉型和蚀变构造岩型两大类,矿石类型分为含金石英脉型和含金蚀变构造岩型两类。据大量绿岩型金矿床脉石英的流体包裹体均一法测温结果统计,其温度多在250-300之间,属中温热液型;将包裹体盐度与金矿联系起来考虑,发现高盐变质流体控制了绿岩带金矿的产生并控制了绿岩型金矿的规模,那些大型及超大型矿床的变质流体的盐度往往都大于32%,甚至高达45%。     

吉黑造山带二叠纪生物古地理区划及特征

吉黑造山带其实质是天山－兴安造山带的东延部分,夹持于华北板块与西伯利亚板块之间,北部为以佳木斯地块为中心的地块群,南部为古生代陆缘褶皱带,东北部为中生代走拼贴的那凡哈达－比金地体。详细研究地期生物地理格局与演化是解决造山带二叠纪古构造格局的关键。     

华北地台重要金矿成矿过程中的流体作用及其来源研究

中生代是华北地台金矿床的最重要成矿时期，该时期的金矿床与煌斑岩和花岗岩类密切伴生。煌斑岩以富金和富LILE为特征，而花岗岩的金含量则甚低；金矿床的铅、氢、氧和硫同位素组成高度分散，表明成矿物质具有多来源性。金矿床中的蚀变时间上从早到晚的演化和空间上从下到上的分带为：由气化－高温(300℃-450℃）阶段的钾长石化，经（高－）中温（200℃-320℃）阶段的黄铁绢英岩化和绢英岩化，变为中－低温（220℃-150℃）阶段的硅化。金在钾交代阶段活化转移，而在黄铁绢英岩化阶段开始沉淀成矿。欧亚板块与古太平洋板块之间以及华北板块与华南板块之间在中生代时期的强烈碰撞、挤压和俯冲造成了华北地台金矿床形成的有利构造环境。俯冲板块俯冲过程中的去气、去碱、去硅和去LILE（包括金）等作用，可形成含金成矿流体。在 俯冲板块进入地幔后，含金流体和分熔产物一起上升并交代地幔楔，形成能够产生富金粕斑岩浆的富集地幔。同时，仰冲板块中的褶皱、变质、花岗岩 的形成、火山作用、煌斑岩侵入、 水／岩反应，以及成矿物质的活化转移和交换作用，促进了金在有利环境中聚集成矿。在上述基础上建立了金在俯冲带的成矿模式。     

华北地块北缘（中段）金矿成矿作用探讨

华北地块北缘（中段）是我国重要的金矿产出地,区域内大型金矿密集分布,在多期次的构造-岩浆作用下,矿床类型多样,成矿作用复杂。本区内金矿主要受太古宙绿岩带控制,在滨西太平洋断裂带与古亚洲断裂带交切影响下,呈北东向与东西向断裂复合控矿的特征。成矿时间主要为新太古代-古元古代、海西-印支期和燕山期。     

河南省洛宁县龙王庙金矿地质特征及矿床成因

河南省洛宁县龙王庙金矿是熊耳山银金多金属成矿带新发现的金矿床．对龙王庙金矿地质特征、物探异常特征、矿床成因及成矿时期进行分析．该矿床形成于中生代华北板块与扬子板块碰撞造山期,矿床类型属基于A型俯冲建立的CMF模式下的造山型热液矿床．矿床的产出受北东向断裂的控制．矿区物探异常显示该区具有较大的找矿潜力,验证钻孔证实M1异常为K1矿体在深部的矿化信息显示．     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Features of Women''s language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

英文诗歌中的喻类修辞

为了有助于提高英文爱好者的个人情操、文化素养和学习兴趣,以及专业人员对英语学习和研究进行多途径的探索,本文通过一些精选诗歌的引证和分析,着重论述了喻类修辞法在英文诗歌中的运用其及效果。     

Man Is Unable to Change the Miserable Life——Analysis of the Arrangement of Four Characters in The Glass Menagerie

Tennessee Williams is considered as one of the most important American playwrights since World War II.The Glass Menagerie is his first successful drama,which describes a tragic situation of family and means to say that Man is unable to change the miserable life,no matter whatever means he try,This essay focuses on the analysis of the arrangement of the four main characters:Laura.Amanda,Jim and Tom to reveal the theme.Laura is fragile.Amanda is brave.Jim is vital.Tom is sensible.And all of them develop and try the different means to struggle against life,but fail tragically.With the evidence,the paper comes to conclusion naturally that Man is unable to change the miserable life,and he dooms to fail.     

Characterization of root-nodulating bacteria on Retama raetam in arid Tunisian soils

The aim of this study is to investigate the diversity of Retama raetam root-nodule bacteria isolated from arid regions of Tunisia. Twelve isolates, chosen as representative for different 16S rRNA gene patterns, were characterized by 16S rRNA gene sequencing and phenotypic analysis. Isolates were assigned to Sinorhizobium, Rhizobium and Agrobacterium. Symbiotic properties of Sinorhizobium and Rhizobium isolates showed a large diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Strain RK 22 identified as Rhizobium was the most effective isolate.     

An Affordable Accurate Evaluation of the Binding Conformations Predicted by Molecular Docking Studies in Bio-System

正Recently,docking has been widely used to predict the binding-modes of protein-inhibitors,when the crystal complexes structure was absent.Most docking algorithms are able to generate a large number of probable conformations,it,however,is difficult to effectively evaluate these docking poses and identify the most reasonable bindingmode.In the present study,on the basis of the crystallographic data of human 3-hydroxy-3-methylglutaryl coenzyme