浙江平山膨润土矿成因的同位素地球化学证据

通过浙江平山膨润土矿床的同位素年龄测定及氢和氧同位素地球化学研究，得出该矿床的成矿年龄为１１０Ｍａ左右，热液流体是来源中中生代大气降水的低温地低水，其成矿温度大致在７０－９０℃之间，从而，对膨润土形成于“表生作用”和“成岩作用”的观点提出了疑义，并探讨了低温热液蚀变的成因机制。     

浙江地开石粘土的氢、氧同位素组成及其形成条件

报道了浙江7个地开石粘土矿床的氢和氧同位素分析数据。应用水-岩石同位素交换作用的基本原理和方法,探讨这些矿床的同位素地球化学特征及其形成条件。同位素交换平衡曲线表明,成矿热液流体起源于中生代大气降水,在300℃的较高温下与围岩发生同位素交换后形成环流地热水;而地开石粘土是在250～100℃的中低温阶段酸性火山岩的热液蚀变产物。此外,还概述了地开石粘土的成矿热液体系从酸性偏还原环境到微酸性氧化环境的演化过程。     

不同类型热液金矿系统的流体包裹体特征

为使流体包裹体研究结果得到较好的解释，避免矿床地质描述与流体包裹体研究结果发生矛盾，本文试图以金矿床为例，建立科学而简便易行的矿床地质与包裹体特征之间的链接。为此，本文简单评述了现有金矿床成因分类方案，建议以主导成矿系统发育的地质作用特征划分5种类型：①浆控高温热液型，包括斑岩型、爆破角砾岩型、铁氧化物型、夕卡岩型等岩浆热液型矿床；②造山型，即变质热液型;③浅成低温热液型——陆相火山岩一次火山岩中的改造热液型；④微细粒浸染型（卡林型或／类卡林型）——沉积岩容矿的改造热液型；⑤热水沉积型（VMS型和SEDEX型）——水下喷出地表的改造热液型。然后，分别介绍了5类成矿系统的标志性地质和流体包裹体特征，找出了它们之间具有成因标志意义的关键性差异；将成矿流体分为改造、变质和岩浆3个端元性成分，发现多数热液矿床具有多阶段多因复成的特点，晚阶段流体均为改造热液或有大量改造热液注入，因此指出，晚阶段的流体、蚀变和矿化特征不能用于判别矿床成因和类型，只有早阶段的特征才能准确指示矿床成因和类型。改造热液以低温、低盐度、低CO2含量为特征，主要来自大气降水和／或海水；变质热液以中温、低盐度、高CO2含量为特征，而岩浆热液则以高温、高盐度、高CO2含量为特征；岩浆热液矿床发育含多种子晶包裹体和高盐度富CO2的包裹体，变质热液矿床发育低盐度富CO2包裹体，改造热液矿床总体缺乏含子晶包裹体和富／含CO2包裹体，大量发育水溶液包裹体。最后，讨论了各类成矿系统发育的岩石圈构造背景，如造山型矿床形成于地壳挤压造山．变质．隆升过程，热水沉积型矿床形成于地壳拉张成盆过程，古生代或更早的浅成低温热液型矿床只能保存在增生型造山带等，提出矿床及其包裹体是研究大陆动力学的理想探针。     

云南省会泽铅锌矿现状及矿床成因探讨

会泽铅锌矿床主要赋存于下石炭系摆佐组(C1b),粗晶白云岩夹灰岩及白云质灰岩中。据前人提供的矿床地质、地球化学、同位素组成、包裹体、方铅矿年龄测定和成矿温度测试等资料研究,认为该矿床的形成经历了同成岩成矿作用,喷流成矿作用和后期热液叠加改造作用,具多源、多期次和多旋回演化的特点,属同成岩-喷流-改造层控型矿床。     

内蒙古草房沟银铅锌多金属矿床地质特征

总结了矿床的矿体地质、矿物成分、矿物嵌布及围岩蚀变特征,初步研究认为:银铅锌矿成矿与变质岩系、断裂构造、岩浆热液活动有关,矿床成因类型为低温岩浆热液型矿床。     

北祁连西段金矿成矿流体特征及成因分析 以鹰咀山、寒山及车路沟金矿为例

北祁连山西段是我国乃至世界上最重要的铜、金多金属矿产成矿地区之一。流体包裹体研究表明,本区主要金矿成矿流体具中低温、低盐度、低密度、浅成等特征;氧同位素研究表明,成矿流体来源主要为岩浆水和大气水;硫同位素研究表明,鹰咀山金矿成矿物质来源为超基性岩和容矿火山岩,寒山金矿为容矿中酸性火山岩并混有少量基底陆源物质,车路沟金矿为奥陶系火山岩（阴沟群）、火山碎屑岩和英安斑岩;鹰咀山成矿时间为413±5Ma、寒山为395±46～303±10Ma、车路沟为350～410Ma;鹰咀山矿床成因为与超镁铁岩有关的中低温热液蚀变岩型金矿、寒山为与剪切带密切相关的中低温热液构造蚀变岩型金矿、车路沟为与斑岩有关的低温热液型碲金矿。     

内蒙古索虎沟金矿床地质特征及成因分析与找矿标志

文章阐明了索虎金矿地质背景和矿床地质特征。矿床产于北东向黑云母二长花岗岩与上侏罗统玛尼吐组火山岩断裂接触复合构造带,金矿体主要呈不规则脉状、透镜状赋存于黄铁绢英岩带内,其下盘蚀变碎裂花岗岩内亦具有金矿化。成矿物质具有多来源性,金来自地幔、建平群片麻岩及铭山花岗岩;同位素测定结果表明,岩浆热液主要来源于上地幔,成矿温度属中低温,成矿作用以交代作用为主,其成因类型应为中低温岩浆热液型金矿床,工业类型为破碎带蚀变岩型。并提出了在矿区及外围的找矿标志以及高~低品位金矿综合基本勘查评价的潜力。     

大兴安岭安铁河铁锌矿床地质特征及成因探讨

安铁河铁多金属矿床位于额尔古纳地块与大兴安岭火山岩带的接触部位,为揭示该区铁锌多金属成矿规律和控矿因素,从区域背景、矿床特征等方面讨论了安铁河铁锌矿床的成矿条件,初步认为该铁矿床成因类型为中低温热液型贯入充填式赤铁-磁铁矿床;锌为中低温热液型细脉浸染状矿床。     

吉林夹皮沟金矿带成矿流体地球化学特征

对夹皮沟地区夹皮沟群变质岩一斜长角闪岩及夹皮沟和二道沟金矿金矿石中的流体包裹体进行了岩相学、显微测温及单个包裹体成分激光拉曼光谱研究。结果表明：金矿石中发育水溶液相、含CO2相及CO2相等三类包裹体，成矿过程中，流体经历了NaCl-H20．CO2体系的不混溶作用，各类包裹体均一温度157．2℃～440℃，盐度1．8％～11．6％NaCleqv，流体密度0．54—0．96g／cm^3；变质岩中以发育含子矿物多相包裹体为主，其均一温度为260℃～480℃，盐度为36．5％-54．8％NaCleqv，流体密度为1．06—1．17g／cm^3，反映了变质流体为一中温、高盐度、高密度均匀NaCl-H20热液体系。成矿流体与变质流体存在明显差异，表明该区金矿床成矿流体并非来自太古代变质热液。结合新近的流体包裹体氢、氧同位素分析结果和测年数据，认为本区金矿成矿流体以来自岩浆热液为主，矿床成因属中生代岩浆热液矿床。     

浙西北银山银多金属矿床地质特征及Rb-Sr同位素研究

银山银多金属矿是近几年来浙西北新探明的中型金属矿床。本文通过矿体地质特征及矿石矿物特征的研究,认为褶曲转折端的虚脱或层间滑动是有利的容矿构造;通过不同金属矿物间的交代和包含特征,厘定了主要金属矿物的生成顺序;闪锌矿Rb-Sr同位素定年结果表明,银山银多金属矿成矿时代为160.5±5.2 Ma,与燕山期(中)酸性岩浆活动作用有关,属低温热液交代型矿床。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence