计算机网络中信息系统技术安全与防范

随着信息产业的高速发展,众多企业都利用互联网建立了自己的信息系统,以充分利用各类信息资源。但是我们在享受信息产业发展带给我们的便利的同时,也面临着巨大的风险。我们的系统随时可能遭受病毒的感染、黑客的入侵,这都可以给我们造成巨大的损失。本文主要介绍了信息系统所面临的技术安全隐患,并提出了行之有效的解决方案。     

火烧油层点火方式研究

点火是决定火烧油层成败的关键因素,文章对目前火烧油层所采取的主要点火方式的适用条件进行研究分析,结合现阶段研究人员室内一系列先导试验及现场总结出的有价值的经验公式,研究分析各个相关因素(地层温度、电点火注气速率、孔隙度等因素)对点火的影响程度,总结出各因素的变化与点火时间的关系,对相关因素的影响进行进一步的整合、推导,考虑多因素前提下总结出一套可以服务于点火施工的设计方案。     

干气密封的应用

在现代石化行业中,常常采用离心泵来输送液态烃,液态烃属于易燃、易爆的危险介质,一旦大量泄漏到环境中,将带来极大的安全隐患和环境污染,对生产装置的安全造成严重的威胁。因此,这类液态烃泵轴封的可靠性和密封性在很大程度上决定了泵是否能可靠、稳定、安全地运行。针对干气密封在液态烃泵上的应用进行了说明。     

Comparison of deterioration of rye under two different storage regimes

Deterioration of stored rye samples was studied at different moisture contents and temperatures. Germination, presence of visible and invisible microflora, and free fatty acid values (FAV) were determined for samples at 10.0, 12.5, 15.0 and 17.5% moisture content (wet mass basis) stored at 10, 20, 30 and 40 °C for 16 weeks. Results of deterioration at constant moisture content (case 1) were compared with previously reported results for deterioration under declining moisture content (case 2). Germination rate was almost the same for all the moisture content samples stored at 10 °C for both cases, but a significant decrease was observed at other temperatures with high moisture content. Fatty acid values remained similar in both cases when rye was stored at 10 and 20 °C, whereas at 30 and 40 °C, FAVs of the rye samples in which the moisture content was maintained were high and increased with an increase in temperature and moisture content. Visible mould appeared early in the samples whose moisture content was maintained. Penicillium spp. and Aspergillus glaucus group were the predominant fungal species present in both the cases throughout the study. The rate of deterioration was significantly different between the two cases.     

Determination of pesticide residues in food matrices using the QuEChERS methodology

The determination of pesticide residues in food matrices is a formidable challenge mainly because of the small quantities of analytes and large amounts of interfering substances which can be co-extracted with analytes and, in most cases, adversely affect the results of an analysis. However, safety concerns require that pesticides of the wide range of chemical properties (including acidic, basic and neutral) should be monitored. Because of the wide variety of food matrices, the sample must initially be cleaned up before final analysis. That is why the analytical chemist is faced with the need to devise new methodologies for determining such residues to be determined in a single analytical run. To accomplish the goal, QuEChERS methodology has been developed. It is a streamlined and effective extraction and cleanup approach for the analysis of diverse analyte residues in food matrices. So far, there have been achieved promising results by liquid or gas chromatography analysis, including pesticides, but also acrylamide, pharmaceuticals and veterinary drugs.     

ZQ2井盐膏层高密度欠饱和盐水聚磺钻井液技术

ZQ2是库车凹陷秋里塔格构造中秋2号构造的一口预探井,吉迪克组～库姆格列木群泥岩段（N1j2 ～ E1-2km1）盐膏层埋藏深度在4545～5827 m,地层特性膏盐层段长、石膏含量高、压力系数高、盐间软泥岩欠压实高含泥质高含水与软黏特性、φ333.375 mm大尺寸井眼,原设计为油基钻井液,后更改为水基钻井液,且井深结构更改为高低压层套打,对水基钻井液技术提出了较高要求。针对地层特性通过改变传统钻井液体系思路引入烯丙基磺酸钠四元共聚物降滤失剂MYK、改性植物胶包被抑制剂NXX、国内首次在欠饱和盐水体系中引入有机盐Weigh2对传统的欠饱和盐水磺化钻井液进行改造升级为聚磺高密度欠饱和盐水钻井液,在实钻过程中表现出包被抑制性强、抗盐膏污染能力强、性能稳定、维护简单、岩屑代表性强,流变性控制优于邻井欠饱和盐水磺化钻井液,在ZQ2井该段盐膏层取得了良好效果,解决了传统欠饱和盐水磺化体系因使用稀释剂致强分散、强依赖性而出现“加～放～加、增黏～降黏～增黏”难题,实现了该层位盐膏层及软泥岩安全快速钻进、井壁稳定、井下安全,电测、下套管一次性成功,为该区块优化井身结构奠定了基础。     

美国现行饮用水水质标准简介

美国现行饮用水水质标准是在《1996年安全饮用水法修正案》的框架内制定的,根据其要求,为每种污染物制定了污染物最大浓度目标值(MCLGs)和污染物最大浓度值(MCLs),由于两者的目的不同,制定方法也有所不同。从内容上,该标准分为一级标准(NPDWRs)和二级标准(NSDWRs)。一级标准为强制性标准,适用于公用给水系统;二级标准为非强制性标准,用于控制水中对美容或感官有影响的污染物浓度。此外,还对其他相关的水质标准、法规作了简要介绍。     

我国安全生产(含安全制造)的科学发展若干问题

以安全生产的科学发展观作为统辖全文的指导思想,对我国安全生产(含安全制造)的典型案例、发展历程和现状趋势进行研究和分析,并从安全生产的特征和属性的高度进行了概括和总结,阐述安全生产的严重性、长期性和战略性.从安全生产的地位作用、定义内涵和发展规律研究和分析安全生产各个要素之间的整体性、关联性和有机性,并进一步揭示安全生产与经济社会发展水平之间的内在联系和非对称抛物线的发展规律,从而为认识安全生产的发展优化提供了定量的模型.探讨安全生产发展总体系各相关子体系和安全良性循环的科技子体系(简称科技子体系),并分解安全生产的科技子体系各阶段和各环节及其关键科技问题,为安全生产的安全科技的良性循环提供思路.对安全生产的管理工作者和安全生产的科技工作者有一定的参考价值.     

A new sustainable hydrogen clean energy paradigm

We analyze the feasibility of a novel, hydrogen fuel cell electric generator to provide power with zero noise and emissions for myriad ground based applications. The hydrogen fuel cell electric generator utilizes a novel, scalable apparatus that safely generates hydrogen (H₂) on demand according to a novel method, using a controlled chemical reaction between water (H₂O) and sodium (Na) metal that yields hydrogen gas of sufficient purity for direct use in fuel cells without risk of contaminating sensitive catalysts. The sodium hydroxide (NaOH) byproduct of the hydrogen producing reaction, is collected within the apparatus for later reprocessing by electrolysis, to recover the Na reactant. The detailed analysis shows that the novel, hydrogen fuel cell electric generator will be capable of meeting the clean power requirements for residential and commercial buildings including single family homes and light commercial establishments under a wide range of geographic and climatic conditions.     

节能型长明灯在火炬安全设施中的应用

针对目前石化系统火炬安全设施状况分析,“石油化工可燃气体排放系统研究”课题组经过大量研究和论证,认为在石化企业工况复杂,自动点火设施将无法代替长明灯时,设置节能型长明灯应用在火炬设施中,是切实可行和必要的。