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元素品位分布的相依性指标--赫斯特指数（Hurst指数）是矿体分布稳定性的动力学控制参量,重标极差（R/S）分析是相依性分析的有效方法.利用R/S分析对胶东大尹格庄金矿黄铁绢英岩内不同勘探线金元素品位系列的Hurst指数计算发现,Hurst指数主要介于0.59至0.89之间,均值为0.75,标准差为0.09,均大于随机行走经验Hurst指数的均值与标准差;计算结果说明元素品位分布存在正相关性,但由于受多种因素影响,其空间分布的相依性具有一定波动.元素品位分布的正相依性显示在特定的地质背景内,矿体连续分布或者间断出现,发育相对稳定,其与大尹格庄金矿的地质事实相吻合. 相似文献
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西里北铁矿含矿岩系赋存于奥陶系中统上马家沟组第一段(O22-1)至奥陶系中统峰峰组第一段(O23-1),矿石类型主要有磁铁矿,其次黄铁矿、赤铁矿,矿体围岩蚀变强烈,含矿岩系中Ba、Mn、W、Sn等元素呈不同程度的富集。本文从含矿岩系到成矿的阶段及控制作用进行分析。 相似文献
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广东阳春市鹦鹉岭多金属矿床地质特征 总被引：1，自引：0，他引：1
鹦鹉岭多金属矿区构造、岩浆活动强烈,具有良好的成矿地质条件.矿体受鹦鹉岭岩体与天子岭组灰岩接触带控制,属矽卡岩型多金属矿床.矿体长150-200m,厚度6-43m,矿床平均品位WO30.23%、Mo0.098%,矿区围岩蚀变强烈,多金属矿化显示明显的水平分带现象.矽卡岩化、云英岩化、角岩化是主要找矿标志. 相似文献
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张彦生 《内蒙古科技与经济》2012,(5):55-57
柴胡栏子金矿矿体赋存于石英脉——蚀变岩中并受构造控制,与金有关主要矿化蚀变为:黄铁矿化、硅化、绢云母化.围岩蚀变是热液成矿作用的重要组成部分,也是热液矿床的主要特征之一.研究金化学性质、金在地质体分布规概况及围岩蚀变能提供成矿时的物理化学条件,热液的性质和演化,以及成矿元素的迁移、富集和矿石沉淀的有关信息,丰富并发展成矿理论. 相似文献
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在多金属硫化矿田利用矿（化）体与围岩的电性差异,使用大功率激电法测量圈定成矿有利地段,推断矿（化）体规模、产状、埋深,设计钻孔施工验证,结合前人地质、钻探、物化探资料综合分析,是寻找深部隐伏矿体（盲矿）,为危机矿山外围及深部找矿行之有效的方法。 相似文献
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通过对扎日尕那地区各地质体含矿特征及地球化学异常分布情况的综合分析,发现Au等元素在该区成矿的可能性较小,w、sn等高温元素在区内成矿潜力巨大,w元素在大多数地质体中平均值接近或超过其1／2浓幅分位值,变化系数在387．9％以上,在二长花岗岩中达到最大值977．2％。目前已发现w在细晶花岗岩中含量可达1．04×10^-2,在二长花岗岩中含量最高可达4990×10^-6,分别超过其工业品位要求。初步确定岩体与围岩接触带及细晶岩脉为w、sn等矿体的可能主要赋存位置（地质体）,并指出了今后工作方向和采用的主要手段。 相似文献
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辽宁省凤城市青城子矿田金（银）矿床赋存于下元古界碎屑岩建造中。属原始沉积,变质蚀变富集,温度、压力、PH值、fo2度变化定位成矿。找矿应遵循：北西向断裂——褪色蚀变带——近东西向硅（钾）蚀变带——金（银）矿体顺序进行。 相似文献
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栾木厂金矿位于华北地台北缘中段金多金属成矿区内,矿区发现金矿脉4条,其中以2号金矿脉为主,现已探获控制的(332)资源量近4t。本文通过对栾木厂金矿区深部及其外围进行物探、化探工作,结合该矿区矿体特征、矿物特征及成矿流体特征研究,初步确定该矿床的成因类型为中-低温热液充填矿床,成矿时期属燕山期。矿床为石英脉型,受北西向断裂破碎带控制,经历了多次热液活动,形成方式以充填为主。重点是2号脉矿化富集规律、矿体三维空间变化规律、断面波形控矿规律,以及金矿体元素地球化学异常模式的研究,对2号脉深部含矿部位进行预测,同时对2号脉SE延伸部位瓦窑沟地区重点开展物化探(高密度电法和化探)工作,预测2号脉南侧和北侧次级断裂或平行断裂有一定找矿远景,为下一步找矿指明了方向。 相似文献
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Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
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. 相似文献
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A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US 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 the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
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. 相似文献
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Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
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. 相似文献
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《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
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《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
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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. 相似文献
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Puay Tang 《The Information Society》1998,14(1):19-31
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. 相似文献
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Milton Mueller 《The Information Society》2001,17(3):151-163
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. 相似文献
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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.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
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. 相似文献
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Leah A. Lievrouw 《The Information Society》1998,14(2):83-96
The main premise of this article is that in information societies generally, and in virtual social contexts particularly, a distinctive style of interaction to facilitate the communication of difference, heterotopic communication , has emerged. It rests on two cultural foundations: an ideological belief in the positive, socially integrating power of communication, and a prevailing ethic of instrumental rationality, subjective individualism, and strategically practiced self-interest. The former is demonstrated by the use of simulation and spectacle as sources of information; exhibitionism/voyeurism as a communicative style; and the awareness of surveillance. The latter is seen in the competitive use of knowledge as a commodity; a surface globalism masking deep parochialism; lateral as well as vertical information inequity; and the use of public versus private as strategies for engagement rather than as spaces. Those who engage in heterotopic communication resort to their 'own devices' both in the sense of personal agendas, strategies, interests, and interpretations, and in the form of the telecommunication tools that help realize them. These personal and technological devices allow individuals with the right educational and technical resources to avoid exposure to disagreement, difference, or other information that does not serve their direct purposes or reflect their particular views of the world; yet they also help convey the appearance of openness, availability, and cooperation. This style of interaction is used strategically in combination with information and communication technologies to gain social or economic advantages, but it may encourage social separatism and parochialism, inhibit the negotiation of disputes, and emphasize competing interests. 相似文献