显微分光光度法区分油漆样品的研究

本文采用色度学和统计分析的方法,对用显微分光光度法区分油漆样品进行了研究。     

用显微分光光度法鉴别圆珠笔油迹的研究

本文借助显微分光光度计系统对几种“色觉”相似的蓝色圆珠笔油墨进行了色度学分析。结果表明,显微分光光度法能有效地鉴别条件等色的圆珠笔油墨。该法准确、可靠,且不破坏检材,对实际检案有重要的意义。     

显微光谱成像技术在汽车油漆截面检验中的应用

目的对汽车多层油漆的横截面进行分层和比对研究。方法运用显微光谱成像技术对收集的12个省市623个汽车漆片样本进行分层,并对截面结构相同或相似的油漆样本进行了区分。结果 623个油漆样本均可以分层,分析出漆层为两层及以上的油漆样本数占总数的87.26%;截面结构相同或相似的油漆样本能够多层同时区分。结论该方法具有科学及实用价值,检验结果可靠,可见光谱成像技术完全可运用拓展到微量物证的检验中。     

用原子吸收分光光度法鉴别陶瓷品

陶瓷制品的鉴别是司法鉴定实践中的一个重要课题．用原子吸收分光光度法精确测定陶瓷制品中Ｐｂ、Ｚｒ、Ｆｅ、Ｚｎ等金属元素的含量．实验结果表明．不仅可区别不同类型的陶瓷制品，而且可区别不同地区或不同工厂生产的陶瓷制品．     

原子吸收分光光度法鉴别窗玻璃的研究

玻璃碎片是刑事案件现场常见的一种物证。在司法鉴定实践中,通过玻璃碎片的鉴别和同一认定,确定其来源,对侦破案情有较大的价值。目前国内公、检、法部门鉴别玻璃碎片,主要放在受力情况、折射率等物理机械性能的测试,玻璃碎片化学成分的鉴定未见报导。玻璃的主要成分是硅酸盐。不同型号的玻璃,使用性能有不同要求,其成分有较大     

显微分光光度法检验蓝黑墨水字迹形成时间的适用性研究

本文利用显微分光光度法对八种不同品牌的蓝黑墨水字迹随时间变化的规律进行了研究,目的是考察该方法在鉴定蓝黑墨水字迹形成时间方面的适用性。实验分析了自然老化条件下的蓝黑墨水字迹在300~700nm波长范围内的反射光谱曲线,并计算墨迹与纸张的色差(△E),考查了△E与字迹形成时间的相关性,结果表明利用显微分光光度法测定蓝黑墨水字迹形成时间具有一定可行性。     

显微激光拉曼光谱鉴别直接染料及其染色纤维

目的 研究显微激光拉曼光谱对直接染料及其染色纤维的鉴别.方法 使用显微激光拉曼光谱仪分别检验了9种直接蓝染料、6种直接黑染料和6种直接红染料及其染色的棉、苎麻和粘胶纤维.结果 当使用显微激光拉曼光谱仪检测直接染料时,514nm激光器的区分能力较强,且光谱基本不受荧光干扰;633nm和785nm激光器的区分能力相似,但较514nm激光器略弱,且光谱更易受到荧光干扰.当使用显微激光拉曼光谱仪检测染色纤维时,若染料本身拉曼光谱信号较强时,其染色纤维的拉曼光谱与染料基本一致;当染料本身拉曼光谱信号较弱且受荧光干扰时,其染色纤维的拉曼光谱受到更大荧光干扰;相同染料染色的不同纤维的拉曼光谱一致.结论 显微激光拉曼光谱是无损检验染料及其染色纤维的有效手段,染色纤维的拉曼光谱基本反映的是染料的拉曼信号.     

SEM检验漆膜厚度鉴别同种颜色的汽车油漆

目的研究扫描电子显微镜测量漆膜厚度的方法对颜色相近的汽车油漆的区分能力。方法应用扫描电子显微镜对不同汽车厂家生产的12块蓝色油漆进行总厚度及分层厚度测量,并对所得数据进行t检验分析。结果在所有两两比对的66组样品对中,在置信度为95％时,用总厚度及分层厚度进行区分,区分率达到100％。结论用扫描电子显微镜微观测量油漆样品总厚度及分层厚度的方法,可对颜色相近的汽车油漆进行有效区分。     

显微分光光度仪检验红色印章油墨1例

1 案例资料1．1 简要案情2006年1月,中央某单位保卫部门对涉嫌伪造、买卖《报告表》问题进行立案侦查,经调查发现少许《报告表》有造假嫌疑。2006年3月,该单位把嫌疑《报告表》11份、比对样本2份送我所理化室,要求检验确定11份嫌疑《报告表》的真假,为案件的进一步侦查提供依据。     

显微红外光谱仪与显微拉曼光谱仪对纺用无色单根纤维的检测

目的研究常见纺用单根无色纤维的有效鉴别方法。方法使用显微红外光谱仪、显微激光拉曼光谱仪研究7大类纺用单根无色纤维的分子光谱。结果显微红外光谱仪、显微激光拉曼光谱仪能有效区分包括棉、粘胶、羊毛、丝、聚酰胺、聚丙烯腈和聚酯在内的7种纤维,是检测单根纤维的有效手段。785nm激发光源是显微激光拉曼光谱仪研究这7类纤维的最佳波长。但由于纺用纤维生产过程的标准化,仅依据红外或者拉曼的峰位置区分同种类、不同产地纤维的效果一般。结论显微红外光谱仪、显微激光拉曼光谱仪是鉴别常见纺用单根无色纤维的有效方法。     

Color analysis of apparently achromatic automotive paints by visible microspectrophotometry

Chromatic secondary pigments are utilized in achromatic automotive paints to create unique paint systems. These pigments may not be observable in reflected light; however, utilizing visible microspectrophotometry (MSP) discriminating data may be gathered. This study analyzed 160 apparently achromatic automotive paints via this technique for spectral evidence of secondary pigmentation. These results were compared with visual observations made via polarizing light microscopy. Positive spectral results were attained in approximately 25% of the black and gray/silver topcoat sample sets, whereas the white topcoat and gray undercoat set yielded no probative spectral data. The black sample set did yield several samples that produced spectral evidence of pigmentation when no visual chromatic data was observed. The results of this study suggest that paint analysis schemes should incorporate visible MSP for apparently achromatic black and gray/silver paint samples.     

Forensic Discrimination of Dyed Hair Color: I. UV‐Visible Microspectrophotometry*†

Abstract: Current protocols for examining hair do not attempt to differentiate hair color using instrumental analysis. In this study, hair samples treated with 55 different red hair dyes were analyzed using UV‐visible microspectrophotometry between 200 and 700 nm. Using air as a background reference gave the best results, although mounting media such as glycerin could also be used. The contribution of the hair substrate is predominantly observed in the range of 300–400 nm while the dye peak is evident in the range of 425–550 nm. It was found that the presence of hair dye reduces the overall intrasample variability of the hair color. In addition, visual inspection and spectral interpretation showed that dyed hair exhibits distinct and discernable shades. The color of all samples was stable during storage and while all hair dyes fade with washing, significant fading of the color was only evident after daily washing for 3 weeks.     

利用傅立叶变换红外光谱技术快速检验静电复印纸

目的建立一种利用傅立叶变换红外光谱技术快速检验静电复印纸的新方法。方法采用傅立叶红外光谱仪对近似静电复印纸进行了快速检验,同时分析了新方法的技术特点。结果采用本文所述的方法可以对近似静电复印纸进行准确的快速检验。结论利用红外光谱技术检验纸张是一种较新颖的,快速、灵敏、准确的纸张检测技术,能对纸张的品牌种类,甚至批次进行鉴别,对大量样本鉴别和碎小纸片鉴别尤其适用。     

裂解气相色谱-质谱法和红外光谱法对红色汽车油漆的比较分析

目的应用裂解气相色谱-质谱法（Py-GC/MS）和红外光谱法（IR）鉴别3种红色汽车油漆,通过二者的比较,考察Py-GC/MS法在微量物证油漆鉴定中的适用性。方法取适量固体样品直接检测。IR检测条件：红外显微镜,透射模式,光阑尺寸100μm×100μm,检测范围为4000-675cm-1。Py-GC/MS检测条件：裂解温度：550℃,裂解时间：0.20min。HP-5MS色谱柱,分流比80∶1;升温程序：起始温度为40℃,保持1 min,然后以8℃/min升至300℃,保持1 min。质谱采用EI源,扫描范围：29~350 amu。结果 3种红色汽车油漆的红外光谱、裂解图谱均能相互区分。通过裂解产物,能获得更多油漆主要成膜物质的成分信息。结论在样品量许可的条件下,应在红外光谱的检测基础上,进一步使用裂解气相色谱-质谱方法来对汽车油漆进行检测,通过互相验证,获得更准确、可靠的油漆鉴定结果。     

Infrared spectra of U.S. automobile original finishes. VII. Extended range FT-IR and XRF analyses of inorganic pigments in situ--nickel titanate and chrome titanate

The identification, analysis, and occurrence in U.S. automobile original finishes (1974-1989) of Nickel Titanate (yellow) and Chrome Titanate (yellow-orange) are described in this report. The titanate pigments are based on the rutile (titanium dioxide) structure and there are only minor differences between the infrared absorptions of rutile and the titanates. Titanate pigment absorptions in paint spectra can thus be easily mistaken for those of rutile. Each of the titanates, however, contains two elements in addition to titanium that can serve to distinguish them using elemental analyses. Fourier transform infrared (4000-220 cm(-1)) and X-ray fluorescence instruments were used in combination for the in situ analysis of the titanates. In addition to titanium, nickel, and antimony, the three main detectable elements comprising Nickel Titanate, all of the commercial products of this pigment that were examined also contained impurities of zirconium, niobium, and usually lead. These elements were also detected in most of the monocoats in which Nickel Titanate was identified, as well as in the Chrome Titanate pigments, and the zirconium to niobium ratio was found to exhibit a wide variation. Nickel Titanate is a relatively common pigment that was identified in nearly three dozen U.S. automobile yellow nonmetallic monocoats (1974-1989), while Chrome Titanate appears to have been used in only a few yellow and orange nonmetallic monocoats. The use of the titanate pigments likely increased after this time period as they were replacements for lead chromate pigments (last used in a U.S. automobile original finish in the early 1990s), and are more amenable for use in basecoat/clearcoat finishes than in monocoats. Minor distortions of the infrared absorptions of rutile, anatase, and the titanates obtained using accessories with diamond windows were noted, and their origins are discussed.     

红外差谱技术用于微量混合油漆的比对检验

对交通事故中的漆片检材进行同一物质比对时,某些情况下难以提取到单一的油漆碎片而是两辆车的油漆混合在一起,给物证比对带来困难。红外差谱技术具有辨别混合物中不同成分的功能,因此可应用于交通事故中混合油漆检材的比对检验。本文对一起交通事故的漆片检材,分别用三种方式提取、制样,用红外光谱仪进行分析,借助红外差谱技术对谱图进行处理,排除混合油漆的干扰。处理后得到的谱图与样本的谱图进行比对,结果显示两者主要官能团吸收峰位置、峰型、峰强度基本一致,可出具比对一致的结论。针对混合油漆检材的比对检验,红外差谱技术可提供支持。     

毒品犯罪的犯罪学定性

从犯罪学的角度,根据毒品犯罪的特征,可以将毒品犯罪区分为五种,即：作为社会政治经济问题的毒品原植物大规模种植行为;作为有组织犯罪的毒品生产、制造和销售行为;作为街头犯罪的毒品零售行为和毒品原植物零星种植行为;作为白领犯罪的洗（毒）钱行为;作为无被害人犯罪的滥用毒品行为。基于犯罪性质的不同,应采取不同的对策。     

汽车罩光漆的ATR-FTIR法检验

目的通过对油漆样品罩光漆成膜物质的检验以区分不同汽车厂家的油漆样品。方法采用衰减全反射红外光谱法（Fourier Transform Infrared Spectroscopy Attenuated Total Reflection Spectroscopy,ATR-FTIR）研究15个汽车厂家提供的356份油漆样品的罩光漆成膜物质。结果在所有油漆样品中,丙烯酸漆出现的频率最高,氨基漆出现的频率最低;在所有厂家中,使用丙烯酸漆的厂家最多,使用氨基氨酯混合漆的厂家最少;在使用相同罩光漆的不同厂家的油漆样品中,通过比较红外谱图可以对样品进一步区分。结论 ATR-FTIR法能够在一定程度上区分不同汽车厂家的油漆样品,从而大大缩小侦查范围,对于涉车案件的快速侦破具有非常重要的作用。     

Detection and Identification of Explosive Particles in Fingerprints Using Attenuated Total Reflection-Fourier Transform Infrared Spectromicroscopy

Abstract:  The application of attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectromicroscopy for detection of explosive particles in fingerprints is described. The combined functions of ATR-FTIR spectromicroscopy are visual searching of particles in fingerprints and measuring the FTIR spectra of the particles. These functions make it possible to directly identify whether a suspect has handled explosives from the fingerprints alone. Particles in explosive contaminated fingerprints are either ingredients of the explosives, finger residues, or other foreign materials. These cannot normally be discriminated by their morphology alone. ATR-FTIR spectra can provide both particle morphology and composition. Fingerprints analyzed by ATR-FTIR can be used for further analysis and identification because of its non-destructive character. Fingerprints contaminated with three different types of explosives, or potential explosives, have been analyzed herein. An infrared spectral library was searched in order to identify the explosive residues. The acquired spectra are compared to those of finger residue alone, in order to differentiate such residue from explosive residue.     

耳纹痕迹的同一认定

耳纹痕迹的同一认定是一个较新的研究领域,虽然目前吸引了众多法庭科学专家的关注,但在同一认定的诸多方面还没有达成共识,研究者们仍处于独立探索和相互讨论之中。从耳纹痕迹同一认定的理论基础、认定程序、测量体系、计算机识别这四个方面入手,分别介绍了此项研究存在的问题及取得的进展。