故障硬盘的数据备份与销毁

硬盘承载着重要数据,它的精密度很高,而且它内部的机械运动快速而准确。一旦这个精密装置的某一部分出现了故障,存储在里面的数据就无法访问,甚至有可能会永久丢失。修复硬盘,找回数据,是数据恢复工程师的神圣使命。一般来说,经修复的硬盘稳定性已大为下降,所以不建议继续使用。但硬盘不用后也不能随意丢弃,因为里面还存储有机密数据,应当将其数据销毁。本文就针对带有坏扇区故障硬盘的数据如何实现数据备份与销毁,以便用户能读出(或销毁)其中重要的数据。     

Belgian Experiences in the Ozonization of Water

After reviewing the uses of ozone in the preparation of drinking water, high purity water for Pharmaceuticals industries, and swimming pools throughout Belgium, a discussion of technological developments made at the Tailfer plant (serving Brussels) concerning the uses of ozone is presented. These subjects include analytical and monitoring techniques developed for ozone, procedures for ozone contacting employed at this plant, treatment of ozone contactor off–gases, and the use of oxygen–enriched process gas to produce supplemental amounts of ozone required periodically. Capital and operating cost data are presented.     

Electrochemical cell current requirements for toxic organic waste destruction in Ce(IV)-mediated electrochemical oxidation process

The electrochemical cell for cerium oxidation and reactor for organic destruction are the most important operation units for the successful working mediated electrochemical oxidation (MEO) process. In this study, electrochemical cells with DSA electrodes of two types, single stack and double stack connected in series, were used. The performances towards the electrochemical generation of Ce(IV) in nitric acid media at 80 °C were studied. The current-voltage curves and cerium electrolysis kinetics showed the dependence on number of cell stacks needed to be connected in series for the destruction of a given quantity of organic pollutant. The presence of an optimum region for Ce(III) oxidation with a contribution of oxygen evolution, especially at low Ce(III) concentration (high conversion ratios), was found. The cells were applied for the Ce(IV) regeneration during the organic destruction. The cell and reactor processes were fitted in a simple model proposed and used to calculate the current needed in terms of Ce(III) oxidation rate and the number of cell stacks required for maintaining Ce(IV)/Ce(III) ratio at the same level during the organic destruction. This consideration was based on the kinetic model previously developed by us for the organic destruction in the MEO process.     

磁碟机病毒破坏机制与防治策略研究

磁碟机病毒及其变种是近几年来病毒技术含量最高、破坏性最强的病毒,已感染数十万台计算机,造成的损失远远超过"熊猫烧香"。为了能有效地防御和查杀该病毒,该文特地对磁碟机病毒进行了深入的研究,分析了磁碟机的破坏机制,指出了磁碟机的种种危害,提出了防治磁碟机的几种技术方法,这对当前防御和清除磁碟机病毒具有一定的现实意义。     

矿柱偏心承载特性与失稳破坏机制研究

荷载重心与矿柱截面形心不重合的偏心承载普遍存在于地下开采工程之中。为揭示矿柱偏心压缩承载特性与失稳破坏力学机制,采用一种模拟偏心压缩的试验装置,开展了5组不同偏心距条件下矿柱轴向压缩试验,得到了偏心压缩时矿柱抗压强度及失稳破坏特征。利用MV-XG280相机监测了加载过程中矿柱表面的散斑图像,结合数字图像相关方法分析了偏心距为1/6矿柱宽度时,其表面位移场与应变场演化过程,研究结果表明：(1)矿柱的抗压强度和弹性模量随偏心距增加呈降低趋势,偏心距越大矿柱越容易达到强度极限而破坏,与均匀压缩相比,偏心荷载作用大大降低了其承载能力;(2)偏心荷载下矿柱的破坏特征为小偏心受压破坏和大偏心受拉破坏。偏心压缩使矿柱受力和力矩的共同作用,表现出偏心距越大整体弯曲变形程度越严重。(3)偏心距为矿柱宽度的1/6时,位移场及应变场反映了试件变形破裂的演化过程,随着荷载的增加,位移场最大位移区域进一步集中,应变场出现明显的局部化带,形成最终导致矿柱破坏的宏观裂隙。     

爆炸洞法炸毁破甲弹研究

应用特制的爆炸洞模拟装置,试验探索了爆炸洞法炸毁破甲弹关键技术。认为利用水介质的柔性阻尼效应和悬挂引爆技术可以大大降低金属射流破甲能力,实现破甲弹的成功炸毁。     

尼龙-1010的增强辐射交联

用凝胶测定技术及广角X射线衍射(Wide angle X-ray diffraction,WAXD)等方法研究了尼龙-1010与添加了交联剂4,4'-双马来酰亚胺二苯甲烷(4,4'-Bismaleimideodephenylmathan,BMI)的尼龙-1010的辐射交联规律,试样的交联G值,结晶结构随吸收剂量的变化,讨论了交联剂存在下辐照对结晶损伤的影响.结果表明,多官能团单体的存在,不仅增强了辐射交联结构的生成,同时也促进了其结晶结构的辐射损伤,损伤的初始剂量减小.BMI单体主要存在于界面区,抑制应力键裂解、加强了界面交联,进一步导致结晶表面缺陷的积累和结晶度Wc下降,表明辐射损伤由晶面开始而逐步向结晶内部伸入.结晶度Wc、微晶尺寸Lhkl与剂量D关系表明,辐照初期W1c及Lhkl的增加与应力链断裂、氢键作用下分子链段重排有关,高吸收剂量的Wc与Lhkl的变化率与结晶比表面大小相关,010面较100面更易受损伤.     

基于金属熔流的未爆弹药销毁技术研究进展

结合未爆弹销毁作业的特点,分析常用销毁方法的适用范围,将烟火切割技术应用于弹药销毁作业,介绍了一种引燃非引爆的销毁方法。概述了金属熔流销毁技术的原理,梳理了燃烧剂配方和燃烧炬结构的研究现状,分析了燃烧剂体系配比,添加剂成分和燃烧炬结构对金属熔流的作业时间、熔穿金属效率、效果的影响。对比文献资料,采用火箭发动机型燃烧炬和利用高热剂、合金剂、稀释剂和造气剂优化燃烧剂,更有利于未爆弹药的销毁。并为下一步深入研究基于金属熔流的弹药销毁技术提供参考。     

Ozone in the United States of America -- State-Of-The-Art

Applications for ozone in the United States have evolved through a lengthy maturation process, which began with drinking water treatment (taste/odor/color removal) in the early 1900s, and grew slowly until acceleration began in the mid-1980s. Although deodorization became a stable market in the 1960s-1970s, these applications were small, for the most part. One of the largest uses for ozone is oxidation of process chemicals in the chemical industry, which began in the USA about the 1940s, and subsequently has spread worldwide. Today, thanks primarily to environmental regulatory pressures which began to impact ozone in the mid-1980s, ozone now is used increasingly in the USA for drinking water treatment and for some municipal and industrial wastewater applications. The U.S. Environmental Protection Agency (EPA) has recognized the growing importance of ozone (> 200 drinking water plants use ozone today), and has appointed IOA representatives to two of its regulatory development committees as stakeholders. Several U.S. cities have installed or are installing wastewater treatment processes for potable reuse purposes, which include the use of ozone. Three full-scale U.S. pulp bleaching plants use tons/day quantities of ozone. Smaller applications for ozone include water treatment for cooling tower waters (biofouling control), swimming pools and spas, marine aquaria, bottled water disinfection and maintenance of high purity waters in the pharmaceuticals and electronics industries. A new application for ozone is in commercial laundries to reduce energy costs and replace chemicals. In mid-1997, a public declaration was made by an expert panel that ozone is Generally Recognized As Safe (GRAS) for contact with foods. This declaration opens the door for ozone to be used in U.S. food processing industries. U.S. research scientists and engineers are at the forefront in studies which define the technical aspects of ozone technologies in a variety of applications employing advanced oxidation, including the treatment of hazardous wastes, groundwater remediation, and process water recovery and reuse in the semi-conductor industry.     

Ozonation of Trace Organic Compounds: Model Predictions versus Experimental Data

This paper is focused on the use of ozone for the elimination of manmade organic micropollutants from drinking waters and waste effluents requiring advanced treatment. A mathematical model was developed to simulate the physical transport and chemical oxidation phenomena prevailing during the process of ozonation. A packed column reactor was constructed in order to test the aptness of the process model. After determining the fluid-dynamic and mass transfer properties of the reactor, stock water solutions spiked with toluene were brought into contact with gaseous O₂-O₃ mixtures. Toluene removal efficiencies observed under different experimental conditions then were compared with the model predictions.