共查询到20条相似文献，搜索用时 78 毫秒
1.
正与普通燃煤电厂相比,燃气-蒸汽联合循环电厂具有初步投资少、建设周期短、热效率高、组合灵活、环保节能等特点,近年来,燃气-蒸汽联合循环电厂在国内外得到快速发展。马来西亚沙巴190MW联合循环电厂是一所基于燃气轮机的联合循环电厂,电厂采用两台燃气轮机、两台余热锅炉(HRSG)和一台汽轮机,即按照2:2:1的比例进行配置安装。该电厂是沙巴地区建设的首台燃气-蒸汽联合循环发电机组,为当地的电网提供了一个重要的调峰电源。燃机机组采用GE公司PG6111FA型。 相似文献
2.
作为西气东输和LNG（液化天然气）输入的配套工程,我国新建了一批350MW等级燃气-蒸汽联合循环机组。介绍日本三菱重工业公司生产的M701F型重型燃气轮机的性能及主要结构特点,分析了其与其它同类产品的优缺点。 相似文献
3.
文章总结了在燃气-蒸汽联合循环发电机组安装过程中的一些经验,对西门子、GE公司几种余热锅炉模块安装方法进行了分析,旨在通过比较几种炉型受热面模块的结构特点、安装工艺、吊装特点和安装成本,为今后燃气-蒸汽联合循环发电机组余热锅炉模块安装提供借鉴. 相似文献
4.
美国GE公司的9FA燃气-蒸汽单轴联合循环发电机组自2003年引进中国以来,迅速占领了中国燃气轮机市场。由于燃机机组启停迅速,省调对半山公司的要求是作为调峰机组来使用。如何加快操作员站电脑响应速度成为了迫在眉睫的任务。 相似文献
5.
蒸汽的导热性能优于空气,其良好的冷却效率能够保证燃气轮机透平叶片承受更高的燃气温度;蒸汽冷却属于内部冷却,所用蒸汽必须是清洁的干蒸汽,取自汽包产生的蒸汽以适于蒸汽纯度的要求,并应对高压蒸汽进行调节。采用蒸汽冷却技术可以减少冷却、密封空气在压气机的抽取量,并可以降低NOx排放量,有利于提高燃气轮机及联合循环的热效率和功率。蒸汽冷却在新一代燃机里扮演着越来越重要的角色。 相似文献
6.
7.
合同交易是电力市场的重要交易方式之一。在单边开放电力市场中．针对谈判型长期合同，构建了发电公司与交易中心的序贯不完全信息讨价还价博弈模型．求解模型并对所得的结果进行分析，认为合同能否达成主要取决于交易中心对发电公司单位发电成本的估计。最后提出设计有效的实时电力市场竞价机制，鼓励发电公司揭露其真实成本，有利于电力长期合同的达成，从而提高整个电力市场的效率。 相似文献
8.
将系统变工况数据运甩MATLAB等数学工具拟合成解析函数，建立该系统变工况下的数学模型，进行热力计算。分别以（火用）效率和毛利润为目标函数对系统进行运行优化，从优化结果我们可以看出制冷量适中、燃机进口空气温度较低（10℃以下）是系统的（火用）效率最高区域，在发电负荷率不低于0．8左右时，该系统的运行有较好的经济效益。 相似文献
9.
指出了中石油哈尔滨石化分公司1．2Mt／aRFCCU焚烧式CO余热锅炉存在的问题，通过增设旁通烟道，新增一组省煤器，利用水热媒技术和选用XD-2000型脉冲燃气吹灰器等改选措施，提高了CO余热锅炉的蒸汽过热能力、烟气能量回收能力和锅炉热效率，节能效果明显，取得了很好的经济效益。 相似文献
10.
内蒙古白乃庙铜金矿床位于华北板块北缘增生型造山带，石英脉型和蚀变岩型矿体受EW向韧．脆性剪切带控制。成矿过程分为三个阶段：旱阶段石英-黄铁矿，乳白色石英和粗粒黄铁矿变形、破碎；中阶段多金属硫化物充填胶结旱阶段变形、破碎的石英角砾和黄铁矿裂隙；晚阶段为石英-碳酸盐细脉，穿切早中阶段脉体和矿物组合。冷热台显微测温结果显示．旱阶段石英中原生流体包裹体的均一温度为248℃～380℃，盐度为4．34％～6．59％，次生包裹体均一温度为180℃～260℃．盐度为3，23％～4．18％NaCleqv；中阶段石英中原生包裹体的均一温度变化范围为215℃～241℃，盐度为2．90％～4．18％NaCleqv，与旱阶段次生流体包裹体一致；晚阶段石英细脉和方解石中的流体包裹体均一温度为137℃～181℃，盐度为0．50％～2．00％NaCleqv。激光拉曼测试结果表明，流体包裹体气相成分为CO2、CH4和N2。成矿流体为低盐度、低密度、富CO2的流体，当这种流体到达剪切带时，由于压力骤然降低发生以CO2逸失为特征的沸腾作用，导致成矿流体过饱和，成矿物质快速沉淀下来形成矿床。白乃庙铜金矿床成矿流体及矿床地质特征与造山型矿床一致，确证了造山型铜矿的存在并提供了实例。 相似文献
11.
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.
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
13.
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
14.
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
15.
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
16.
《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
17.
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
18.
《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
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