Windows 8回收站取证分析

在计算机取证过程中,对于删除文件的分析常常提供有价值的信息。知道在哪里找到被删除文件并且能够理解文件被删除过程中产生的元数据,这是一个合格的计算机取证人员必备的素质。本文对Window 8系统的回收站与传统的Windows XP系统的回收站的相似点和不同点进行了对比分析,并详细说明了Windows 8系统回收站的工作细节,以期为计算机取证人员提供帮助。     

基于Profibus-DP的西门子S7—300 PLC与ABB 800XA数据通信的实现

本文介绍基于Profibus—DP通信协议的西门子S7—300PLC与ABB 800XA系统之间的数据通信。详细描述了分别通过S7—300 PLC CPU的DP接口和CP342—5通信模块与ABB 800XA系统通信两种不同条件下的有关通信配置及实现数据通信的过程。     

A CALPHAD-type Young's modulus database of Ti-rich Ti–Nb–Zr–Mo system

Accurate Young's modulus is the necessity for the design of biomedical Ti alloys. A combinatorial method of the diffusion couple, nanoindentation, electron probe microanalysis (EPMA), and CALculation of PHAse Diagrams (CALPHAD) techniques has been utilized to construct the Young's modulus database of Ti alloys with various compositions in the present work. Two groups of body-centered cubic (bcc) Ti–Nb–Zr–Mo quaternary diffusion couples annealed at 1273 K for 25 h were experimentally prepared. Subsequently, the composition-dependent mechanical properties in the wide compositional range of Ti-based alloys were obtained by using EPMA and nanoindentation probes. Finally, on the basis of the measured Young's moduli in the present and previous work and the modeling parameters of Young's modulus of Ti–Nb–Zr system, the Young's modulus database of bcc Ti–Nb–Zr–Mo system was established through the CALPHAD approach. The CALPHAD-type database of bcc Ti–Nb–Zr–Mo system can provide the accurate Young's moduli of Ti alloys with wide compositions.     

μC／OS—Ⅲ在Cortex—M3处理器上的移植

为了将μC／OS-Ⅲ移植到Cortex—M3处理器上,选用RealView MDK作为软件开发平台,针对Cortex—M3处理器特性编写了移植所需的C语言和汇编语言源代码,并验证了移植的正确性。移植后的μC／OS-Ⅲ能够稳定运行于Cortex～M3处理器上。该移植对大部分Cortex—M3处理器具有通用性,对其他架构处理器的μC／OS-Ⅲ移植具有参考作用。     

基于IEC61131-3标准的PLC编辑模块设计与实现

基于IEC61131-3标准设计一个可编程逻辑控制器（PLC）编辑模块,并给出了主要数据结构和算法的设计。通过测试表明用户界面友好,操作简单,对后续开发具指导意义。     

FTIR investigation of ethylene coordination and polymerization on reduced Cr/SiO2 catalyst

FTIR spectroscopy was applied to study the initial steps of ethylene polymerization on reduced chromia-silica (0.5 wt% Cr/SiO₂). To decrease the speed of the reaction small doses of gas were introduced to the catalyst in each run and C₂D₄ was used to confirm band assignments. At the initial steps of the reaction only ethylene molecules coordinated to probably Cr _A ²⁺ cations were observed. The concentration of such complexes was estimated to be about 50% of the total amount of Cr atoms in the sample. The FTIR spectrum of the polymer formed at the initial doses of C₂H₄ (when [C₂H₄] [Cr]) was found to be slightly different from that formed after excess ethylene was introduced onto the catalyst ([C₂H₄] > [Cr]).     

基于单片机的多功能充电器的设计与实现

本课题主要研究基于单片机的多功能充电器,解决对不同电池的快速充电。通过对ATmega8的深入研究,利用它的高性能,设计完全实现了电池充电器设计的功能。本设计可以通过按键切换,对的密封铅酸电池(SLA)和镍镉电池(NiCd)进行充电,并通过LCD清楚地看到其充电状态。同时利用放大电路和Atmega8本身的AD转换器显示对电池电压和电流的实时测量,以较好的控制充电过程,保护电池。     

铂铑包覆钼合金搅拌器的研制

介绍了铂铑包覆钼合金搅拌器的结构与技术要求,以及搅拌器的制作与使用效果。研制结果表明,国产搅拌器达到了日本同类产品的水平。     

Analysis of Intermetallic Phases Formed on Surface Vapor Oxidized H13 Hot Work Steels in Molten Aluminum

In this paper, the author dipped surface vapor oxidized H13 steel specimens into 700℃ molten aluminum liquid for a certain period of time. Analyze the intermetallic phases formed on the H13 samples surface with optical microscope and X-ray diffraction method. The observation of immersion test sample's cross-section shows that Fe3O4 film will protect die substrate from molten aluminum erosion. The identification of the intermetallic phases reveals that they consist of 2parts, which is named as the composite layer and the compact layer. Further investigations are made in order to know the phase constituents of the 2 layers, they are Al8Fe2Si (outer composite layer), (AlCuMg) and Al5Fe2 (compact layer),respectively. The experimental results show that on the same specimen, a convex surface with bigger radius of curvature is more likely to be molten and the melting loss speed is also faster than a flat and smooth surface. The thickness of compact layer on a smooth surface is much bigger than that of the convex surface. Therefore, the author supposes the compact layer is favorable in stabilizing the die surface material from further melting loss, as their formation on the die surface, the melting loss speed will decrease.     

Intraspecific variation and interspecific differences in sex pheromones of sibling species inCtenopseustis obliquana complex

The specific status ofCtenopseustis obliquana pheromone-types I, II, and III has been more fully examined. Females of types I and III produce a mixture of (Z)-8- and (Z)-5-tetradecenyl acetates (Z8-14:Ac, Z5-14: Ac). The previously reported different ratios of these two components in females of the two types (type I=8020, III=9010) have been reinvestigated. The median ratios of each type differed significantly, although there was some overlap in the ranges of these ratios. A field cage trial showed that males of type III are attracted to females of type I, so the observed differences may be ascribed to intraspecific variation. In contrast to females of types I or III, females of type II produce Z5-14Ac but no Z8-14Ac. The electroantennogram (EAG) profile of antennae of type II males shows a maximum response to Z5-14Ac, while the EAG profiles of types I and III show a strong response to Z8-14Ac. In wind tunnel tests using mixtures of these two compounds, type II males prefer blends consisting of all or mostly Z5-14: Ac, while type I males showed a preference to a mix of 70% Z8-14Ac plus 30% Z5-14Ac. We found that type I males are attracted to type I females when offered a choice between type I and type II females in a field cage test and that type II males similarly prefer type II females. Males of types I and II have specialist cells for Z8-14Ac and Z5-14Ac but differ with respect to relative densities of these cells and to further cell types responsive to other alkenyl acetates. Type IIC. obliquana is considered therefore a sibling species of types I and III. In addition, the amount of Z5-14Ac produced by type II females varied geographically. Females from the North Island produced significantly less (median=1.2 ng) Z5-14Ac than females from the South Island (median=2.2 ng). Type II populations in the North Island morphologically resembled sympatric type I, rather than type II from the South Island and are designated as type II (North Island). Type II (North Island) populations have so far been found only at Rukuhia (near Hamilton) and from Kerikeri. In contrast, type II populations are sympatric with type III populations over much of the South Island. In a field cage trial, males of types II and II (North Island) were attracted to females of both II and II (North Island). We tentatively ascribe the differences between type II and type II (North Island) to intraspecific variation.