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81.
目的研究常见的打印字迹与不同印章印文交叉时序的相关性,为检验提供依据。方法应用DVI-300微痕迹色差分析系统对制成的实验样本进行实体观察,并对微痕迹色差模型图进行特征分析。结果先墨后朱,交叉部位字迹边缘状态完整,等高线宽度、流向未见明显变化;先朱后墨,交叉部位中心字迹等高线排列出现游离状态,色料分布发生数字图形曲面变化。结论用本系统可以观察、分析朱墨交叉部位的微观特征和无损检验研究。  相似文献   
82.
经调查,2007-2009年近三年来,山东省机械企业一线职工的工资收入增长缓慢,收入水平偏低,职工收入分配差距不断扩大,职工对企业工资决定机制参与度低,职工对收入分配不公平反映强烈。分析造成这种状况的原因,主要是有关法律法规不完善、政府宏观调控乏力、企业内部工资决定机制设置不合理、工会组织发挥作用不够等。改进的对策和建议是:加快修订和完善企业工资分配等方面的法律、法规;强化政府宏观调控的措施和手段;指导企业建立公平合理的工资分配机制;充分发挥工会组织在调节企业收入分配中不可代替的作用。  相似文献   
83.
Abstract:  Laser desorption mass spectrometry (LDMS) is emerging as a technique for questioned document examination. Its use is limited to detecting ink dyes that are neutral or singly charged. Several inks contain dyes that are multiply charged and LDMS cannot be employed for their identification. We have successfully detected >20 polyionic dyes that can be used in the manufacture of inks using matrix-assisted laser desorption/ionization (MALDI) MS, directly from paper, with the matrix, 2-(4-hydroxyphenylazo)benzoic acid (HABA), and the additive, diammonium hydrogen citrate (DAHC). For example, Acid Violet 49, a charged dye containing one positively-charged site and two negatively charged sulfonate groups, cannot be detected by LDMS, but forms intact, singly charged ions in the MALDI MS experiment. The method described is also useful for identifying multiply charged dye mixtures that are used in modern pen inks.  相似文献   
84.
Abstract: Anyone with a computer, scanner, and color printer has the capability for creating documents such as identification cards, passports, and counterfeit currency. Laser desorption mass spectrometry (LDMS) has been demonstrated as a powerful tool for colorant analysis. Inkjet printers are now moving largely toward the use of pigments as colorants; their insolubility makes analysis by simpler methods such as thin‐layer chromatography no longer an option. Recent developments in pigmented inkjet printer inks, such as gloss optimizers that coat pigment particles, may prohibit colorant analysis by LDMS. We demonstrate here that pigments used in inks from two Epson printers can be detected and analyzed by LDMS. Also, LDMS spectra of various colors created using a 4‐cartridge (cyan/magenta/yellow/black, CMYK) inkset are evaluated, to begin to develop an approach for unraveling LDMS data from real samples, to determine the number of inks used by a printer, and the chemical composition of the colorants.  相似文献   
85.
三维激光扫描仪是用于采集实物三维几何数据信息的先进仪器。其运用全自动立体激光扫描技术,可以精确迅速地获取实物三维信息。将获得的信息通过点云数据处理软件转化为三维模型,实现实物的"实景复制"——三维建模。这种技术方法可以用于立体足迹的形态特征检验,在检验能力和效果上都更为出色。  相似文献   
86.
抄本《孔雀经音义》卷末所附音图为日语五十音图之最早版本。其中之“か”行音由汉字“呬”和キコカケク五个假名构成,其中“呬”为行首汉字。本文从“呬”字入手,通过考察其反切注音和日语假名注音,澄清了音图中汉字“呬”与假名“キ”之间的音韵对应关系。在此基础之上,又通过考察梵汉对译字“呬”与梵语之间的对应关系,作为最终结论指出,《孔雀经音义》卷末所附音图中的“呬”行音,是基于梵语字母表ha行音建构起来的。  相似文献   
87.
The ability to determine the age of fingerprints would be immeasurably beneficial in criminal investigations. We explore the possibility of determining the age of fingerprints by analyzing various compounds as they diffuse from the ridges to the valleys of fingerprints using matrix‐assisted laser desorption/ionization mass spectrometry imaging. The diffusion of two classes of endogenous fingerprint compounds, fatty acids and triacylglycerols (TGs), was studied in fresh and aged fingerprints on four surfaces. We expected higher molecular weight TGs would diffuse slower than fatty acids and allow us to determine the age of older fingerprints. However, we found interactions between endogenous compounds and the surface have a much stronger impact on diffusion than molecular weight. For example, diffusion of TGs is faster on hydrophilic plain glass or partially hydrophilic stainless steel surfaces, than on a hydrophobic Rain‐x treated surface. This result further complicates utilizing a diffusion model to age fingerprints.  相似文献   
88.
Detection of aged fingerprints is difficult because they can degrade over time with exposure to light, moisture, and temperature. In this study, aging fingerprints were visualized by time‐resolved spectroscopy with an ultraviolet‐pulsed laser. Fingerprints were prepared on glass slides and paper and then stored under three lighting conditions and two humidity conditions for up to a year. The fluorescence intensities of the fingerprints decreased with time. Samples were stored in the dark degraded less than in sunlight or under a fluorescent lamp. Samples were stored under low humidity degraded less than under moderate humidity. As the storage period increased, a fluorescence emission peak appeared that was at a longer wavelength than the peak visible in earlier spectra. This peak was used for visualization of an aged fingerprint over time. An image of the fingerprint was not initially visible, but an image appeared as the time since deposition of the fingerprint increased.  相似文献   
89.
Three‐dimensional (3D) technologies contribute greatly to bullet trajectory analysis and shooting reconstruction. There are few papers which address the errors associated with utilizing laser scanning for bullet trajectory documentation. This study examined the accuracy and precision of laser scanning for documenting trajectory rods in drywall for angles between 25° and 90°. The inherent error range of 0.02°–2.10° was noted while the overall error for laser scanning ranged between 0.04° and 1.98°. The inter‐ and intraobserver errors for trajectory rod placement and virtual trajectory marking showed that the range of variation for rod placement was between 0.1°–1° in drywall and 0.05°–0.5° in plywood. Virtual trajectory marking accuracy tests showed that 75% of data values were below 0.91° and 0.61° on azimuth and vertical angles, respectively. In conclusion, many contributing factors affect bullet trajectory analysis, and the use of 3D technologies can aid in reduction of errors associated with documentation.  相似文献   
90.
Previously unreported line patterns visible under ultraviolet light were observed on a proportion of plain white A4 printer/copier paper from different manufacturers. These Ultraviolet Line Patterns (UVLPs) usually appear as stripes down the vertical length of the paper. Typically, the UVLPs were found to “repeat” through the ream in a predictable way, while also changing. It is postulated that the repeating nature of the UVLPs is a result of the way that paper is manufactured. This leads to the ability to sequence the sheets compared to their original source paper. Even in the absence of UVLPs, it is possible to use our observation of the manufacturing process to anticipate the order of several sheets of paper and conclusively associate them, in some cases, by physically fitting their machine cut edges and crossing paper fibers. Such a novel approach to examining questioned documents would be highly useful in forensic casework.  相似文献   
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