色谱法对笔中油墨种类鉴别的研究

发布时间：2018-04-10 15:02

本文选题：法庭科学 + 可疑文件　；参考：《首都师范大学》2005年硕士论文

【摘要】：在法庭科学中常常会涉及到可疑文件。需要对使用的墨水的书写时间进行鉴定。自从1950以来,各国的法庭科学工作者经过不懈的探索,逐步建立了一些方法应用于办案,有的鉴定结论已被一些国家的司法部门所接受。但是,由于油墨组成成分的复杂性和其测定的干扰性,可疑文件与墨水书写时间的鉴定仍然是当前法庭科学的难题之一。因此色谱法对笔中油墨种类鉴别的研究有其重要的意义,本论文分四部分进行研究。第一章介绍了笔的发展历史及油墨的主要成分、进行墨水鉴定的理论依据,综述了近年来国内外可疑文件与墨水书写时间鉴定的发展与应用,包括化学鉴定法、溶剂提取鉴定法、色谱法、光谱法等。第二章系统研究了液相色谱鉴别蓝色和黑色圆珠笔,选择了适当的提取剂和流动相条件,研究了重现性、检出限和纸张的影响,并对收集的国内外不同厂家或同一厂家不同品牌的65种蓝色圆珠笔和32种黑色圆珠笔油墨进行了分类,根据主要成分的色谱峰的保留时间、液相色谱—质谱中的质荷比、二维图、三维图等信息将蓝色圆珠笔分为十类,黑色圆珠笔分为六类。第三章研究了毛细管电泳法分离和区分水溶性钢笔墨水及黑色签字笔,考察了BGE、酸度、有机添加剂、提取剂等的影响,选择了最佳分离条件,分析了21种不同品牌的水溶性钢笔墨水和95不同品牌的签字笔。第四章研究了通过染料成分的变化确定字迹形成相对时间,将纯染料字迹和圆珠笔油墨字迹放在强光照射、红外光照、紫外光照、加热和室内自然光等条件下,然后再从纸上提取用HPLC分析,发现光的照射下染料和墨水的成分变化很大,根据老化后染料成分及含量的变化推测了反应机理。
[Abstract]:Suspicious documents are often involved in forensic science.The writing time of the ink used needs to be evaluated.Since 1950, after unremitting exploration, court scientists in various countries have gradually established some methods to deal with cases, some of which have been accepted by the judicial departments of some countries.However, due to the complexity of the composition of ink and the interference of its determination, the identification of the writing time of suspicious documents and ink is still one of the most difficult problems in forensic science.Therefore, it is of great significance to study the classification of ink in pen by chromatography. This paper is divided into four parts.The first chapter introduces the development history of pen and the main components of ink, the theoretical basis for ink identification, and summarizes the development and application of the identification of suspicious documents and ink writing time at home and abroad in recent years, including chemical identification.Solvent extraction and identification, chromatography, spectral method, etc.In the second chapter, we systematically studied the identification of blue and black ballpoint pens by liquid chromatography, selected the proper extraction agent and mobile phase conditions, studied the effects of reproducibility, detection limit and paper.65 kinds of blue ballpoint pens and 32 kinds of black ballpoint pen inks collected from different manufacturers at home and abroad or different brands of the same manufacturer were classified. According to the retention time of the chromatographic peak of the main components, the mass charge ratio in liquid chromatography-mass spectrometry,Blue ballpoint pen is divided into ten types and black ballpoint pen is divided into six categories.In chapter 3, the separation and separation of water-soluble pen ink and black pen by capillary electrophoresis were studied. The effects of BGE, acidity, organic additive, extractant and so on were investigated, and the optimum separation conditions were selected.The water-soluble pen ink of 21 different brands and the signature pen of 95 different brands were analyzed.In chapter 4, the relative time of writing formation is determined by the change of dye composition. The pure dye handwriting and ballpoint pen ink are placed under the conditions of strong light, infrared light, ultraviolet light, heating and indoor natural light.Then the paper was extracted by HPLC analysis and found that the composition of dye and ink changed greatly under the irradiation of light. The reaction mechanism was inferred according to the changes of the composition and content of dyes after aging.
【学位授予单位】：首都师范大学
【学位级别】：硕士
【学位授予年份】：2005
【分类号】：D918.92

【引证文献】