提高循环流化床锅炉经济性分析

第二热电厂75t/h循环流化床锅炉DGG75/3.82-2型锅炉是单汽包自然循环,高温“气-固”旋风分离,全钢结构炉架的循环流化床锅炉。由于我公司的循环流化床锅炉自机组投运以来曾多次出现问题,影响了机组的安全经济运行。在这期间我们总结了大量的经验和教训,采取了诸多保证锅炉安全运行的措施,取得了较理想的效果。本文试图从循环流化床锅炉的几个主要经济指标（燃烧效率、飞灰含碳量、煤耗、风机电耗）方面进行分析,并依据我厂现状,总结一些提高其经济性的运行调整经验,以便在实际运行中加以实施,充分发挥循环流化床锅炉的优势。     

350MW循环流化床锅炉机组启动节能降耗措施

本文先对350MW循环流化床锅炉结构做简析,然后在设备改造、锅炉运行调整与汽机运行调整基础上,详细分析和阐述350MW循环流化床锅炉机组启动节能降耗措施。     

循环流化床锅炉主要部件的防磨措施

循环流化床锅炉中金属部件及耐火层的磨损是造成其运行事故的主要原因之一。因此,循环流化床锅炉中金属部件和耐火层的防磨措施,直接影响循环流化床锅炉机组的经济运行和安全运行。     

准能矸电2×330MW循环流化床CFB锅炉模拟量控制设计特点

阐述了内蒙古准能矸电2×330MW（CFB）机组锅炉模拟量控制系统的设计思路以及控制范围,针对循环流化床锅炉运行的特点,对区别于煤粉炉的模拟量控制进行了积极的探讨和设计,旨在提高循环流化床锅炉的设计和控制水平。     

准能矸电2×330MW循环流化床CFB锅炉模拟量控制设计特点

阐述了内蒙古准能矸电2×330MW(CFB)机组锅炉模拟量控制系统的设计思路以及控制范围,针对循环流化床锅炉运行的特点,对区别于煤粉炉的模拟量控制进行了积极的探讨和设计,旨在提高循环流化床锅炉的设计和控制水平.     

循环流化床锅炉给煤系统改造应用与分析

循环流化床锅炉给煤系统稳定运行是保证机组正常出力的关键,本文通过改造实例,系统介绍了传统给煤系统的缺点及原因分析,通过对给煤系统的改造解决了堵塞、窜烟、结焦等缺陷;对循环流化床锅炉机组稳定运行,提供了良好的理论依据和实际指导意义。     

浅谈循环流化床锅炉的结焦问题

循环流化床锅炉的结焦问题是锅炉运行中较为常见的问题,而结焦问题直接影响着锅炉机组的安全、经济、稳定运行,因此需要熟悉锅炉的结焦原因和预防措施,提供锅炉的安全性和经济性。     

电厂循环流化床锅炉运行中炉膛爆燃事故的发生与预防

随着循环流化床锅炉机组在数量和容量上的不断发展,与之相适应的如何保障锅炉安全、稳定、高效的运行成为火电事业中的重要课题之一。本文对火电厂用循环流化床锅炉运行中炉膛爆燃事故的发生机理与预防措施加以分析和阐述。     

循环流化床锅炉结焦预防措施

循环流化床锅炉技术是目前迅速发展起来的一项高效、清洁燃烧技术。结焦就是循环流化床锅炉运行中较为常见的故障,它直接影响到锅炉的安全经济运行。结合循环流化床锅炉的运行特点,根据作者几牟来的流化床锅炉调试和运行经验,分析流化床锅炉结焦的主要原因,并对如何预防循环流化床锅炉结焦进行了探讨。     

提高300MW循环流化床机组灭火不跳机恢复成功率

为及时、有效、迅速地处理锅炉MFT不跳机的事件,避免和减少因锅炉MFT造成跳机,导致机组非计划停运,本文介绍了《300MW循环流化床锅炉MFT不跳机应处理措施》,详述了循环流化床锅炉灭火不跳机条件的初次设计、运行优化,以期提高300MW循环流化床机组灭火不跳机恢复成功率,建立危急事件的长效管理机制和提高应急处理能力,将损失降低到最低限度。     

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.     

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.     

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.     

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