核电站海水冷却系统换热器防腐技术的研究与应用

针对传统的海水-工业水换热器与海水接触部位容易被腐蚀,从而造成换热器产生泄漏的问题,通过与广东工业大学合作,展开了对换热器防腐蚀技术的研究,最终获得了比较好的防腐蚀技术并应用于实际生产中.     

滨海电厂直流供水系统中循环水泵材质选择

S31803、CD3MN和CN7M三种材质的材料均具有抗海水腐蚀性能,并且力学性能也能满足海水循环水泵的使用要求。在涉外工程中,海水循环水泵材料推荐采用S31803和CD3MN材质,与CN7M材质相比,上述两种材质在技术上和经济上更优。     

螺旋板换热器自动焊接设备研究

螺旋板换热器设备时一种功能独特的新型换热器,其主要有金属板卷构成,两个金属材质的半卷可以形成螺旋形状的通道,冷热不同状态的流体可以借助螺旋板壁实现有效的换热活动。这种换热器就具有不可拆卸与可拆卸两种不同的形式,不可拆螺旋板换热器端面焊缝由于双线螺旋形状,而且每台焊缝轨迹都不相同,造成加工时只能采用手工焊接,劳动强度大、焊缝质量不稳定,结合螺旋板式换热器的结构特点,探讨采用红外线传感器对通道端面焊接部位的焊缝进行有效追踪,进行自动化焊接。     

浅谈H2S气体对油、套管的腐蚀特性及防护措施

针对H2S给油田钢铁管材、设备造成巨大破坏的严重情况,分析了H2S对油、套管腐蚀机理。另外,从温度、金属材质的性能等方面,简述了对油、套管的防护措施。     

制氢装置中容器封头应力腐蚀裂纹的检测与分析

制氢装置在实际生产过程中,由于氢气和氧气的析出使得不锈钢设备的特殊部位积聚一定量碱液形成应力腐蚀（SCC）,从而导致应力腐蚀破裂,发生安全事故。文中针对1Cr18Ni9Ti材质的压力容器的应力腐蚀现象进行了合金成分分析、硬度测定和金相检验。测试分析结果表明,系统中的0H^-和封头部位的焊接接头结构形式引起碱液浓缩是造成奥氏体不锈钢产生应力腐蚀破裂的主要原因。对此文中从压力容器的结构设计、合理选材和最大限度地消除焊接残余应力等几方面提出了一些预防措施。     

冷却水入口温度对管式换热器腐蚀速率的影响及机理分析

为了研究冷却水入口温度对管式换热器内壁腐蚀所产生的影响,本文基于茂名市梅江江段的水样进行模拟换热器腐蚀过程实验,模拟实验研究了冷却水入口从20℃-40℃的区间内,冷却水对管式换热器腐蚀速率的变化,记录实验数据,并就流速对腐蚀速率的影响逐一作了机理分析。结果表明:腐蚀速率显示随流速的增加而增加,但是当流量增加到一定程度后,腐蚀速率随流速的增加而减小,腐蚀机理为:腐蚀是由对流传质和表面反应共同控制,低流速以对流传质为主,流速增大起到方便致腐蚀离子微生物向换热器表面扩撒,腐蚀速率随流速的增加而增加。     

连续复合管技术在矿场的试验与应用

<正>本文介绍了井下用纤维增强连续复合管的结构功能、技术特性、操作设备和适用条件。通过矿场应用表明,该项技术作业成本低,操作方便,能有效解决注水井管柱腐蚀、结垢的问题,具有推广应用前景。油田绝大多数注水管柱均使用钢制管材,井下注水管柱由于化学腐蚀、细菌腐蚀,容易产生管柱腐蚀穿孔、结垢,严重影响注水管柱的使用寿命。频繁更换注水管柱不仅造成油管费用增大,同时也增加了作业维护费用,不利于油田低成本、高效益开发。     

海水淡化稳定运行的影响和控制

沧东电厂单台日制淡水量为10000t/d（共两台）低温多效海水淡化装置,自2006年3月投运以来,运行一年半时间,受到海水预处理及其他方面的影响,运行中的问题逯渐暴露出来,主要表现在板式换热器效率降低,海水淡化造水比下降,根据运行中对数据及解体检查分析,采取必要的改进措施,使海水淡化蒸发装置稳定运行,降低蒸发器结垢腐蚀情况。从而延长设备使用寿命,降低维护成本,进一步提高安全可靠稳定性,进行必要的改进试验,提高海水淡化装置的有效利用率,使低温多效海水淡化装置得到广泛的应用和发展,同时为港区供水提供可靠保证。     

甲醛回收塔防腐蚀材质优化分析与研究

本文介绍了当前聚甲醛生产装置甲醛回收塔系统普遍存在的设备腐蚀问题,并分析了甲醛回收塔腐蚀机理,根据理论分析并结合设备改造使用情况对设备防腐蚀选材进行了优化,达到低成本维护、长周期运行的目的,对国内外同类装置防腐蚀材质优化具有指导性意义。     

喷淋冷却器腐蚀原因分析及改进措施

V-605喷淋冷却器出现局部腐蚀的问题。设备发生多次的腐蚀泄漏,造成了该装置的多次停工。本文分析设备的腐蚀原因及其形成机理,通过更换设备材质,并提出相应的防腐技术措施,使设备的腐蚀问题得到改善,生产装置能长周期稳定运行。     

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.     

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.     

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     

Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels

<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese     

More than Skin Deep – Understand Skin Biology by Means of Dermatogenomics

<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages.