Dating of Seals Produced with Stamp‐Pad Ink Using Gas Chromatography Method

Seals are often placed on important documents, and determining the date when a seal was affixed can be important to assess the authenticity of a document. In this study, thirty‐seven different brands of stamp‐pad inks and three different types of paper were used to make diachronic samples of the seals. The volatile components of stamp‐pad ink were determined, and the stamp‐pad ink was classified by gas chromatography with a flame ionization detector. Calibration curves were created to show the relationship between the content of volatile stamp‐pad ink components and the age of stamp‐pad ink entries stored under natural aging, UV‐induced aging, and heating aging conditions. The experimental results showed that GC was useful in the analysis of stamp‐pad ink and applicable for determining the relative age of stamp‐pad ink entries in some cases where the seal was placed on the document within 3 months.     

傅里叶红外图像——单点模式法无损鉴别中性笔墨水色痕

中性笔墨水色痕形成文件的检验是目前法庭科学实验室经常遇到的问题,文中对市场上收集到的15种不同品牌的中性笔进行了鉴别,采用单点模式无损鉴别的方法区分墨水的色痕。实验结果表明,根据红外特征谱图所形成红外吸收峰的位置、峰的数量、峰的强度及形状和二阶导数光谱可将不同生产厂家或牌号的黑色中性笔墨水区分开来。     

拉曼光谱成像技术检验朱墨时序中书写笔种类对检验结果的影响研究

目的考察在运用拉曼光谱阵列面扫描检验朱墨时序的方法中书写笔油墨种类对检验结果的影响。方法根据拉曼谱图的不同对搜集的188种书写笔（包括22种黑色圆珠笔,62种蓝色圆珠笔,62种黑色签字笔,42种蓝色签字笔）进行扫描并分类,采用拉曼光谱阵列面扫描技术对书写笔与同一印泥和印油形成的朱墨时序样本进行检验。结果 188种书写笔被分为4大类23小类,4类书写笔与印泥或印油形成的朱墨时序样本都得到了较好的检验结果。结论在本实验条件下,书写笔油墨种类对拉曼光谱阵列面扫描检验朱墨时序的检验结果没有影响。     

碳素墨水显现胶带粘面手印原理与工艺初探

目的：通过实验得出碳素墨水方法显现胶带粘面手印的原理与恰当工艺。方法：用不同方式制作样本,验证显现原理;控制不同条件,优选出恰当的工艺。结果：归纳出碳素墨水方法显现胶带粘面手印的原理及恰当的操作工艺。结论：本研究结果对实际应用有较大参考价值。     

Molecular study of time dependent changes in DNA stability in soil buried skeletal residues

Stamp marks are used as a unique identification for a range of items, but these can be erased for criminal activities. Erased marks can sometimes be recovered by etching or magnetic means. The present study looked at the application of Fry's reagent to recover erased marks from steel. The investigation also demonstrated that Fry's reagent can deteriorate on storing and will require a longer etching time. The effect of different applied forces of stamping was investigated, and the depth of the underlying deformation was determined by etching after varying degrees of metal removal. The amount of metal needing to be removed depends on the force applied to the die. Metal removal also affects the time needed for recovery. The underlying structural change remains as a hidden identification mark, and could potentially be used by manufacturers as an unseen identifier. A model for the underlying deformation is proposed.     

Comparison of natural and artificial aging of ballpoint inks

Abstract:  Solvent evaporation caused by aging from ballpoint inks was measured by gas chromatography/mass spectroscopy (GC/MS). The sample preparation was carried out with two different thermal desorption systems. The results are compared. Thirteen inks were classified with regard to their solvents, polymers, and additives. The variation of the aforementioned compounds caused by aging was monitored for naturally and artificially aged samples. In this paper, the results are compared and discussed with respect to forensic casework.     

激光拉曼光谱区分黑色圆珠笔字迹初探

针对现在广泛使用的薄层色谱分析技术带有破坏检材的缺点,提取采用激光拉曼光谱法进行无损检验,通过对收集的5个国家10种牌号样品进行初步比对分析,区分率达90%以上.     

谈傅立叶红外图像系统法鉴别红色印油的种类

随着经济的发展,各种合同、证书的使用日益增多,对印油的鉴定愈显重要。关于印油的检验已有一些研究成果,但大都属于有损检验。找到一种简便快捷无损鉴定印油的方法,是很有必要的。采用Spotlight傅立叶变换红外图像系统的反射模式对14种不同品牌的红色印油所形成的印文样品进行直接测试,取得了满意结果,达到了区分不同产地、厂家的目的。该法快速、准确、客观并且不破坏样品。     

计算机辅助绘图在药用植物科学绘画中的应用

［摘要］推荐一种运用传统照片及现代计算机辅助绘图技术结合手工绘制生物墨线图的方法。将彩色生物照片利用Photoshop等图片处理软件变为单色，在A4纸上彩色打印后，结合手工绘制即可得到一幅生物墨线图，最后将墨线图扫描至计算机进一步处理。