对海洋石油装备国产化的思考

装备国产化是一件利国利民的事,具有十分重要的战略意义,实现海洋工程重大技术装备国产化更是一项长期的、艰巨的任务。本文总结了中海油工程2009-2013年度装备现状,详细分析了2009-2013年度国产化实际情况、国产化的益处、国产化所关注的问题所在;从思想上对国产化在中海油系统中存在的问题提出了意见。根据海油实际情况,提出了五大措施来推进装备国产化。     

Genetic Control of the Enantiomeric Composition of Ipsdienol in the Pine Engraver, Ips pini

The genetic nature of pheromone variation within species has rarely been studied, and never for male-produced long-range pheromones. Males from western North American populations of Ips pini produce predominantly (R)-(−)-ipsdienol, whereas those from eastern North American populations produce higher proportions of (S)-(+)-ipsdienol. From a population in the hybrid zone, we divergently selected lines for the opposing pheromonal types and then created F1, F2, and backcross lines. We formed additional F1, F2, and backcross lines, first by using populations with low (+)-ipsdienol enantiomeric ratios near to and distant from the hybrid zone, and then by using populations with high (+)-ipsdienol enantiomeric ratios near to and distant from the hybrid zone. Three types of analysis were employed: (1) line means analysis; (2) Mendelian analysis of assigned high and low (+)-ipsdienol enantiomeric ratio phenotypes when applicable; and (3) Castle–Wright estimation of the number of effective factors. Dominance at one autosomal locus explains much of the variation in ipsdienol blend between the divergently selected lines. Thus, as in all previously studied female long-range pheromone systems, a major genetic element is implicated. The populations with low (+)-ipsdienol enantiomeric ratios near and distant to the hybrid zone differ negligibly for this trait. We confirmed previous studies showing slightly higher ratios of (+)-ipsdienol at the hybrid zone than in a distant eastern population and reveal a genetic basis for this difference.     

煤矿主通风机在线监测系统网站的建立

运用 Ｗｉｎｄｏｗ ｓ 环境网络标准开发的环境Ｗｉｎｓｏｃｋ 和Ａｃｔｉｖｅｘ，以Ｂｒｏｗ ｅｒ／Ｓｅｒｖｅｒ 结构开发出煤矿主通风机在线监测系统的网站，实现了煤矿的远程自动化管理。     

非计算机专业数据库教学改革探讨

非计算机专业学生认识和了解数据库,掌握数据库技术,能够提高学生解决实际问题的能力。但由于数据库课程理论性强,概念不易理解,造成学生学习积极性不高,学习目标不明确等情况,最终影响了教学效果。因此,根据学生的实际情况寻求一系列措施进行教学改革,力求取得良好的教学效果。     

真空压力浸渍用少胶粉云母带的分析对比

本文从应用角度论述了VPI少胶粉云母带的性能要求，少胶带与浸渍树脂的相容性对绝缘性能以及电老化性能产生的影响，对国内外产品性能作了分析对比并简要介绍了国内外制造方法。     

DG3000/26.15-II1型锅炉主要技术问题探讨

邹县发电厂扩建工程2×1000MW超超临界机组锅炉是东方锅炉厂与其技术支持方BHK公司、BHDB公司联合研制的第一个1000MW等级超超临界机组锅炉项目,自2004年6月份合同签订以来,初步设计进展顺利,现就其主要技术问题及解决方案阐述如下。     

THE BATTLE OF THE SEALS

This article is primarily about the seals of the National Security Agency (NSA) and its Central Security Service (CSS). Specifically, this article provides, for the first time, a copy of the NSA seal that preceded the current one, a copy of the CSS seal, and their respective histories. A brief biography of the current CSS Deputy Chief and a very brief history about CSS itself is also provided. A number of references are made to James Bamford's two books: Body of Secrets (May 2001) and The Puzzle Palace (1982). My intention is not to nitpick his works. Rather, I simply wish to clarify points that readers may find confusing, especially since he is the world's leading authority on NSA. I not only admire Bamford's investigative journalism, but also strive toward the very high standard that he has set.     

Shape effects on the activity of synthetic major-groove binding ligands

In this work we present the results of a molecular simulation study of two different tetracationic bis iron(II) supramolecular cylinders interacting with DNA. One cylinder has been shown to bind in the major groove of DNA and to induce dramatic coiling of the DNA; the second is a derivative of the first, with additional methyl groups attached so as to give a larger cylinder-radius. The simulations show that both cylinders bind strongly to the major groove of the DNA, and induce complex structural changes in A–T rich regions. Whereas the parent cylinder tends to bind along the major groove, the derivatised cylinder tends to twist so that only one end remains within the major groove. Both G–C rich and A–T rich binding sites for the derivatised cylinder are discussed.     

谁将主导高清视频接口 DisplayPort or HDMI

备受关注的Dell 3008WFP日前终于在官网上正式发售,由于集成众多多媒体视频接口,这款显示器早已成为全球电脑发烧用户关注的焦点。在这款机器上,除了拥有100％的广色域外,最吸引玩家的一点还在于它是首款配备了全新DisplayPort接口的液晶显示器。于是,一场关于新一代高清视频接口的争夺战由此引发……