Response Assessment of Thermal Papers from Four Continents to Fingerprint Development by Heat

Latent fingerprint deposits on thermal paper sourced from the U.S., China, the U.K., and Australia have been visualized by heating. U.S. and Chinese sourced paper produced two distinct types of fingerprint development. In one type (type 1), the paper dye colors where the deposit is present (as previously reported) and in the other type (type 2) the ‘inverse’ of this gives paper coloring only in areas not coincident with the deposit. Both development types gave identifiable fingerprints, the majority fading within 24 h of heating. Fingerprint development from U.K. and Australian sourced paper was exclusively type 1 and resistant to fading. Temperatures for fingerprint visualization were higher for U.S. paper (64–71°C) and Chinese paper (75–95°C) than for U.K. and Australian sourced paper (43–50°C). Particularly for Chinese sourced paper, these temperatures were within a few degrees of the normal paper color temperature. A mechanism for type 2 fingerprint development is proposed.     

电子文件与纸质档案价值鉴定之比较分析

本文主要从电子文件的价值鉴定和纸质档案的价值鉴定入手,从不同的方面比较了两者的异同,重点阐述电子文件的价值鉴定。笔者根据比较分析电子文件的价值鉴定和纸质档案的价值鉴定,对两者的鉴定工作提出了几点建设性的意见。希望本文的论述既能对档案工作者有所帮助,又能对档案研究人员有所启发。     

波长色散X射线荧光光谱法检验纸张中的常量和微量元素

目的研究X射线荧光光谱元素分析法对常见纸张的鉴别能力。方法应用波长色散X射线荧光光谱仪对29个纸张样品中常量和微量元素进行了定性和定量分析。结果在样品量为mg级时,不但检出填料中常见的Si、Ca、Mg、Cl等主体元素,还能检出Al、S、P、K、Fe、Sr等10多种微量元素。结论用该方法既可对纸张的种类进行鉴别,对不同品牌的打印纸也有较好的区分。     

Chelex-100法提取滤纸血痕DNA影响因素的比较

目的改进滤纸血痕DNA提取方法,建立更简便、廉价,适合当前DNA建库需要的提取方法。方法将752份滤纸血痕分成四组,分别按照四种不同的Chelex-100法进行DNA提取并进行比较研究;63份新鲜血痕分别按照两种方法提取并进行对比研究。结果对于陈旧滤纸血痕,四种提取方法的检测成功率无显著差异(P>0.05);对于新鲜血痕,两种提取方法的检测成功率有显著差异(P<0.05)。结论对于建库陈旧滤纸血痕样本的DNA提取可采用不加纯水处理,直接加入Chelex-100的方法进行。     

使用油红O显现潮湿纸张上的油脂手印

通过使用物理显影液(PD)和油红O(ORO)试剂在潮湿纸张上做了指纹显现效果的比对,发现ORO在热敏纸和白纸上比PD表现出更好的效果,但是牛皮纸上效果不明显。ORO很少破坏物证,可作为潮湿纸张上指纹显现的良好方法。     

纸张检验综述

纸张检验是文件检验鉴定技术的重要组成部分之一。文章对有关纸张种类鉴别和纸张相对形成时间检验的文献进行了综述,介绍了用于纸张种类和形成时间检验的无损和有损方法,对各种方法的适用性进行了归纳总结。     

注重考试环节提高教学质量

考试是教学的重要环节,不同的学科、不同的课程有不同的特点。命题应严格遵循全面考核,突出重点,理论联系实际,注重考查学生的实务操作能力这一原则。在试题内容上,应难易适度;在阅卷方式上,应根据题型的不同采用不同的判分标准;在应试技巧上,应教导学生要懂、吃透基础知识,学会总结典型题型。同时应加强学生考前模拟训练。     

基于短波紫外光荧光现象快速鉴别静电复印纸的种类

目的 建立无损、快速静电复印纸的鉴别方法.方法 利用文检仪短波紫外光,对30种不同品牌或相同品牌不同批次的静电复印纸测试并比对分析.结果 相同条件下,不同纸张的紫外荧光现象不同,根据纸张在短波紫外光激发下的荧光强弱、荧光纤维条的长短、粗细、弯曲形状和分布稀疏程度等特征,可鉴别不同品牌或相同品牌不同批次的静电复印纸.结论 该方法是一种简单、无损、高效、实用的检验方法.     

公文碑与古代行政程序探析

中华法系"重实体、轻程序"的特色,几成为人们的共识,但中国古代公文碑所呈现的繁复行政过程及"程序化"特色,对这一共识形成挑战。历时长久、适用广泛、形式多样、存量可观的公文碑是研究中国古代行政权、行政程序、行政监管等法律制度的珍贵史料。碑石上的"行政授权""行政许可"以及"反向行政"等内容,揭示了中国古代行政权在制度建构、秩序维护和社会运行中的关键机制。对包括碑刻在内的传统史料的系统整理和重新发现,对于构建中国传统法律话语体系,具有不可忽视的意义。     

Profiling and imaging of forensic evidence – A pan-European forensic round robin study part 1: Document forgery

The forensic scenario, on which the round robin study was based, simulated a suspected intentional manipulation of a real estate rental agreement consisting of a total of three pages. The aims of this study were to (i) establish the amount and reliability of information extractable from a single type of evidence and to (ii) provide suggestions on the most suitable combination of compatible techniques for a multi-modal imaging approach to forgery detection. To address these aims, seventeen laboratories from sixteen countries were invited to answer the following tasks questions: (i) which printing technique was used? (ii) were the three pages printed with the same printer? (iii) were the three pages made from the same paper? (iv) were the three pages originally stapled? (v) were the headings and signatures written with the same ink? and (vi) were headings and signatures of the same age on all pages? The methods used were classified into the following categories: Optical spectroscopy, including multispectral imaging, smartphone mapping, UV-luminescence and LIBS; Infrared spectroscopy, including Raman and FTIR (micro-)spectroscopy; X-ray spectroscopy, including SEM-EDX, PIXE and XPS; Mass spectrometry, including ICPMS, SIMS, MALDI and LDIMS; Electrostatic imaging, as well as non-imaging methods, such as non-multimodal visual inspection, (micro-)spectroscopy, physical testing and thin layer chromatography. The performance of the techniques was evaluated as the proportion of discriminated sample pairs to all possible sample pairs. For the undiscriminated sample pairs, a distinction was made between undecidability and false positive claims. It was found that none of the methods used were able to solve all tasks completely and/or correctly and that certain methods were a priori judged unsuitable by the laboratories for some tasks. Correct results were generally achieved for the discrimination of printer toners, whereas incorrect results in the discrimination of inks. For the discrimination of paper, solid state analytical methods proved to be superior to mass spectrometric methods. None of the participating laboratories deemed addressing ink age feasible. It was concluded that correct forensic statements can only be achieved by the complementary application of different methods and that the classical approach of round robin studies to send standardised subsamples to the participants is not feasible for a true multimodal approach if the techniques are not available at one location.