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1.
钢结构建筑因自重较轻、施工方便成为主流的建筑类型,但过去对该产业评估研究较少,缺乏对其资源生产率及环境影响的充分认识。本文选择中国西部、东北和中部地区的15个钢结构建筑设施作为研究对象,利用物质流分析钢结构建筑物质流动过程中输入、输出物质种类和重量,结合钢结构建筑所产生的经济价值,核算其资源生产率,同时对钢结构建筑中钢铁的物质流全过程进行生命周期评价。结果表明：①生产过程中95%的钢铁得到利用,5%成为废钢铁,钢结构建筑中单位建筑面积资源消耗量从高到低排序为矿物、水、氧气、化石能源、生物质,其中东北地区钢结构建筑的矿物质消耗量最大,达到107 kg/m2;②根据钢结构建筑直接输入物质所占比例,西部地区、东北地区、中部地区钢结构建筑资源生产率分别约为692元/t、512元/t、610元/t;③钢结构生命周期对环境影响最大的阶段为钢铁生产阶段;如果考虑循环利用,其环境影响最大出现在钢结构加工阶段,且钢铁循环利用可显著降低钢结构产业的环境影响。依据以上研究结果,东北地区钢结构建筑资源生产效率最低,应提高其资源生产效率,大幅度促进循环利用,实现可持续发展。 相似文献
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实现联合国可持续发展目标的进度评估和路径选择,依赖于相关指标的定量评价及对社会经济和自然环境系统耦合关系的刻画。物质流和社会经济代谢分析方法基于质量守恒和生命周期思想,可以深刻地描述物质存量动态变化及其与流量的关系,分析资源和产品贸易及其对区域物质循环的影响,理解不同资源在生产与消费过程中的耦合与冲突关系。社会经济系统中物质代谢的分析和调控,是实现可持续发展的重要前提,也有助于绿色经济、循环经济、低碳经济等可持续发展战略的顺利实施。文章介绍了物质流和社会经济代谢分析方法的基本框架,并通过具体案例展示其如何用于分析全球、国家和产业可持续发展中的中长期资源、能源和气候挑战及相应的对策,从而助力实现联合国2030年可持续发展目标。在此基础上,提出了推进中国物质流和社会经济代谢研究的若干建议。 相似文献
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区域可持续发展生态评估的物质流分析研究进展与展望 总被引：10，自引：0，他引：10
可持续发展的生态评估是当前国际生态经济学与可持续发展研究的前沿问题之一，物质流分析通过度量人与自然之间的物质交换及其环境影响，定量评估人类社会经济系统的生态持续性，是一个重要的研究方向。本文在简述物质流分析及其发展历程的基础上，分析了该方法应用于区域可持续发展生态评估的基本原理。重点综述了国内外物质流分析相关研究进展，认为对比于国外的蓬勃发展，该方法在我国尚未获得普遍应用，尚处于起步阶段。同时，国内已有的研究也主要以实证分析为主，理论探讨相对薄弱；实证研究又以经济系统物质流分析为主，但多侧重国家尺度，少区域物质流分析；而产业部门物质流分析则相对较少，且偏重能源矿产采掘业，对其他物质生产部门的关注较少。研究同时指出，可持续性阈值、物质使用环境影响的度量、不同物质重量的可加和性、隐流系数的计算、系统内部物质流分析、数据获取与应用范围限制等理论与技术问题将是区域可持续发展生态评估物质流分析下一步的研究重点。 相似文献
4.
中国产业部门的能耗强度特征及节能减排的分类实现路径 总被引：6，自引：2，他引：4
产品生产过程中除了直接消耗能源之外,还有通过中间产品投入而产生的间接能源消耗。因此,仅仅依靠提高能源利用效率来进行节能减排,其作用是有限的,必须要综合考虑生产过程中对能源、物质投入的需求。本文通过投入产出方法分析了我国2002年各个产品部门单位产值的直接和间接能源消耗,发现大部分产品部门单位产值的间接能耗都大于直接能耗,即生产过程中的大量物质投入导致了大量的间接能源消耗。因此,要实现节能减排的目标,直接能耗高的部门要提高其能源利用效率,而间接能耗高的部门要提高其中间投入的利用效率,同时要推动低能耗的服务业的发展以及在全社会推进“减物质化”发展,减少物质消耗而导致的间接能源消耗,而这需要人力资本的大量积累以及服务业的发展。 相似文献
5.
中国能源消费的分解分析 总被引：24，自引：8，他引：24
经济发展对能源消耗的不断增加同能源储量不断减少之间的矛盾日趋严重,能源危机时威胁着世界经济的发展.我国正处于全面工业化时期,经济快速发展,能源使用效率低,近几年不少地区出现的不同程度的"三荒"(电荒、煤荒和油荒)正是这一矛盾的体现.为了深入了解我国经济发展和能源使用效率对能源消耗的影响,本文运用分解模型把能源消耗总量的变化分解为经济增长效应和能源强度效应.计算结果显示:1978年～2003年间能源效率年均增长率为4.76%,能源消耗总量没有随GDP的增长而同比增长,经济发展与能源消耗之间实现了一定程度的相对脱钩;研究期间中国经济发展的增长效应共使能源消耗量增加约22.8×108t标准煤,而能源消耗强度降低所带来的减量效应共使能源消耗量减少约11.7×108t标准煤.若要在实现2020年国内生产总值(GDP)在2000年的基础上翻两番的目标的同时,使能源消耗总量保持在2000年水平,2000年～2020年间能源使用效率年增长率需达到7.2%,这是十分困难,但经过努力实现这一期间能源效率年均增长5%,从而把2020年的能源消耗总量控制在20×108t标准煤以内是有可能的.特别值得注意的是2001年～2003年的能源消耗增长速度超过了同期的GDP增长速度,能源使用效率随经济的发展不但没有提高,反而在下降. 相似文献
6.
能源资源开发过程中的环境影响和资源消耗问题日益凸显,而现有的以经济价值为衡量标准的评价方法对此考虑不足。本文从能源开发本质是为社会提供净能源这一层面入手,结合能值的相关理论方法,把能源开发过程的能源投入与产出及环境影响均视为能量的流动或贮存,建立了基于能值的能源投入回报法,并以大庆油田进行实例分析。根据实地调研数据,基于能值的能源投入回报方法结果显示大庆油田的能源投入回报值已经从2001年的6.3下降到2012年的3.6,说明其为社会提供的净能源正在递减。与标准能源投入回报方法相比,基于能值的能源投入回报方法结果下降趋势更明显,更符合实际情况。此外,基于能值的能源投入回报可以视为一种反映能源开发活动生态变化的指标,该方法关注经济活动的能源资源基础,从相对物理的视角反映了能源资源开发中的资源与环境问题。 相似文献
7.
由于各国资源禀赋条件和生产、消费水平不同,各种资源及其产品的国际贸易有利于国际分工的深化和整体生产力水平的提高,使全球资源的分配更加合理.但出口国为了提供出口商品,需开采本国资源,这一方面降低了本国资源的保障程度,另一方面出口商品的生产和本国资源开采加大了本国的环境压力;为发展本国经济发生的进口则对进口商品来源国的环境产生压力.因此国际贸易总是伴随着环境负担的转移.为了定量衡量实物国际贸易中附带的环境负担转移,本研究运用生态包袱概念和算法计算了中国1990年～2002年国际贸易对本国环境和别国环境引起的环境压力,并对中国这一时期的实物国际贸易做了详细分析.研究结果表明:1990年～2002年间以重量计算的中国的物质进口量为每年1.0×108t～4.0×108t,年增长率为11.3%;进口商品所附带的生态包袱为每年4.3×108t～25.0×108t,年增长率为15.6%;出口量为每年0.8×108t～1.9×108t,年增长率为7.5%,出口商品的生态包袱为每年3.0×108t～12.5×108t,年增长率为11.2%;实物贸易平衡(进口盈余)为每年0.25×108t～2.1×108t,总体趋于增长;生态包袱平衡(进口物质附带的生态包袱-出口物质附带的生态包袱)为每年1.1×108t～14.3×108t.1990年～2002年间中国每进口1t的物质对物质来源国的环境造成约4.2t～6.7t的环境压力,而中国出口1t的物质对本国环境产生大约3.9t～8.3t的环境压力. 相似文献
8.
中国铜资源开发利用中的物质投入 总被引：5，自引：1，他引：5
生产物品和提供服务都需要物质投入,所有的投入物质或迟或早都会变成排出物质(废弃物或排放物)返回到环境之中.因此,通过测量物品(服务)的物质投入量就能估计其潜在的环境冲击.同时,测量生产过程中各个阶段的物质投入能够帮助生产者认清资源消耗的分布状况,锁定重点部位,为改进生产方式和工艺流程,提高资源利用率提供决策支持.铜是工业生产中的重要原材料,铜的生产在提供了铜资源的同时,也消耗和搬动了大量的物质,产生环境压力.本研究以中国粗铜生产为研究对象,量化了我国铜生产的物质投入和生态包袱,并对其国际实物贸易环境负担转嫁进行了计算分析. 相似文献
9.
液晶显示器在其生产制造和使用等阶段将产生对环境和人群健康不利的各种因素。应用生命周期评价方法对其制造和使用阶段原辅材料、能源和污染物质进行影响评价分析,减少环境影响贡献最大的影响因子使用量。该结果对消费者进行产品选择和生产者进行改进产品结构都具有一定的现实意义。 相似文献
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A research 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 in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
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. 相似文献
12.
《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
13.
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
14.
《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
15.
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
16.
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
17.
Active biological molecules 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 therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
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. 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
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
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