四种操作系统共存于同一台计算机中的实现

针对很多计算机应用场合 ,要求一台计算机具有多种职能 ,需要多种操作系统支持的需求 ,本文讨论了多种操作系统共存于一台计算机中的技术     

Analysis of intron sequence variability of the conservative HMG-box of Sox9 genes in allotetraploids and their original parents

The Sox genes of allotetraploids and their original maternal red crucian carp (Carassius caassius red var.) and original paternal common carp (Cyprinus carpio L.) were detected by PCR with the designed primers based on the conserved HMG-box sequence in different species. Sequencing of Sox genes indicated that two Sox9 genes (Atsox9a and Atsox9b) existed in allotetraploids, while only one Sox9 gene existed in red crucian carp (Rcsox9a) and common carp (Ccsox9b) . All of the four Sox9 genes contained an intron in the HMG-box. with the sizes of 413 bp, 703 bp, 401 bp and 714 bp, respectively. Moreover, the introns obeyed the rule of "GT-AG" . A high similarity was observed between introns of Atsox9a and Rcsox9a (94.4%), Atsox9b and Ccsox9b (97.8%). Interestingly, the deduced amino acid sequences of their corresponding exons all shared 100% identity. Thus, introns of the HMG-domain of Sox9s in allotetraploids and their original parents have not only the length polymorphism but also intron variability. Our results provide significant molecular evidence for the origin and evolution of allotetraploids.     

基于LPC2214的Flash存储器的应用

介绍了Flash存储器K9F5608U0C和SST39VF160的特性,给出了微处理器LPC2214与它们的硬件连接电路图,以及对它们进行读、写、擦除等操作的应用软件.     

李益首次从军时间地点考辨

本文纠正了长期以来人们对李益首次从军时间和地点的错误认识,认为其首次从军时间应在大历九年至大历十二年间,而非建中初;地点在凤翔节度使李抱玉军中,而非邠宁节度使韩游瑰、凤翔节度使邢君牙或渭北节度使臧希让军中.     

数据库系统的体系结构比较

随着信息技术的不断发展,现代企业和政府的信息化进程不断加快。数据库系统是企业信息、资讯的核心和仓库,是当代计算机系统的重要组成部分,它提供了可靠的存储和高效的查询功能,为企业信息管理与决策提供了稳固的支撑。本文展示了Oracle 9i与SQL Server 2000的体系结构和工作原理,并对其相关功能进行比较。     

一种基于ARM9的UPS网络监控方法

提出了一种基于ARM9的不间断电源网络监控方法,重点分析了利用Linux裁剪构造UPS实时操作系统,在其上搭建嵌入式web服务器,运用CGI与Web服务器的交互,最终实现基于B／S模式的网络监控方法．     

Hélène Metzger: the history of science between the study of mentalities and total history

In this article, I examine the historiographical ideas of the historian of chemistry Hélène Metzger (1886–1944) against the background of the ideas of the members of the groups and institutions in which she worked, including Alexandre Koyré, Gaston Bachelard, Abel Rey, Henri Berr and Lucien Febrve. This article is on two interdependent levels: that of particular institutions and groups in which she worked (the Centre de Synthèse, the International Committee for History of Science, the Institut d'Histoire des Sciences et Techniques (Sorbonne) and the École Pratique des Hautes Études) and that of historiographical ideas. I individuate two particular theoretical aspirations pursued by the historians in Metzger's milieu: the ideal of total history and the study of the human mind. These two objectives were seen by Metzger and many others as implicating each other. Moreover, Metzger and other historians wanted to integrate the practice of commentary of texts in the realisations of those ideals. I argue, however, that these objectives proved very difficult to realise at the same time. One tradition which stemmed out of these discussions, exemplified by Bachelard, Canguilhem and Foucault, focused on the mind and knowledge, and renounced commentary of texts and total history as it was understood by the historians of the Centre de Synthèse. The latter, however, did not really pursue the study of the mind. Moreover, historians like Metzger and Koyré who practised an attentive analysis of texts could not realise total history.     

异源四倍体鲫鲤及其原始亲本Sox9基因HMG保守区内含子遗传变异性分析

参照不同物种中Sox基因HMG保守区序列设计简并引物,扩增了异源四倍体鲫鲤及其原始亲本红鲫(Carassius carassiusred var.)和鲤鱼(Cyprinus carpioL.)的Sox基因.对不同片段大小的Sox基因测序,结果表明,四倍体鱼中存在两个Sox9基因(Atsox9a和Atsox9b),红鲫和鲤鱼中只发现一个Sox9基因(Rcsox9a和Ccsox9b).这4个Sox9基因在HMG盒中均含有内含子,大小分别为413bp,703bp,401bp和714bp,其插入位点遵守GT-AG法则.其中Atsox9a与Rcsox9a,Atsox9b与Ccsox9b的内含子序列都具有很高的一致性,分别为94.4%和97.8%,这表明内含子序列变异率较低.有趣的是,根据它们的外显子所推导的氨基酸序列一致性均为100%.因此,四倍体鱼及其原始亲本Sox9基因HMG基序内含子不仅具有长度多态性,而且内含子之间存在遗传变异性,这为进一步探讨异源四倍体鲫鲤的起源和进化提供了重要的分子生物学证据,同时也为正确掌握内含子的位置信息,功能和进化起源有着十分重要的作用.     

1-三氟甲基-β-咔啉-3-羧酸正丁酯的晶体结构研究

通过核磁共振氢谱等对1-三氟甲基-β-咔啉-3-羧酸正丁酯的结构进行表征, 利用单晶X射线衍射法测定其结构.该晶体属单斜晶系,空间群为P21/c, 晶体学参数为:a= 0.81231(4)nm,b = 1.71197(8)nm, c = 1.16388(6)nm; α=90°, β= 93.615(2)°, γ=90°; Z=4, F(000)=696,R1=0.1756.     

凝胶-固相反应法制备SrBi2Ta2O9

以碳酸锶、五氧化二钽、三氧化二铋等物质为原料，采用凝胶一固相反应法制备了SrBi2Ta2O9。利用XRD、DTA、SEM等分析手段对其形成过程和烧结特性进行了研究。结果表明，球磨时间、烧结时间以及烧结温度对烧结密度和SrBi2O9的分解都有明显的影响。介电性能显示，该方法合成的SrBi2Ta209和传统的固相法合成的SrBi2TaO9性能差别不大。