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1.
目的探索电工胶带带基的元素检验方法。方法利用扫描电镜/能谱法(SEM/EDS)对电工胶带带基中的主体元素进行定量分析,通过SPSS软件对SEM/EDS定量分析法检测出的主体元素(Cl和Ca)相对含量进行统计分析;利用X射线荧光光谱法(XRF)对电工胶带带基中的微量元素进行定性分析。结果34个品牌红色电工胶带组成的561组样品对通过SEM/EDS定量分析法可以区分539组,区分率达到96.1%;根据XRF法定性分析测出的Mg、Al、Si、S、Ti、Sb、Ba、Pb微量元素的不同组合可将34种电工胶带分成11组,两种方法结合可使不同品牌红色电工胶带的区分率达到98.4%。结论SEM/EDS法和XRF法结合可以实现同种颜色、不同品牌电工胶带的高效区分。  相似文献   

2.
目的研究激光刻蚀等离子体质谱法对打印纸品牌的区分能力。方法收集了国内20个不同品牌的打印纸,应用激光剥蚀等离子体质谱方法进行元素分析,并采用SPSS系统聚类方法对测试数据进行处理。结果依据元素响应值比值的差异将20个不同品牌的打印纸区分为12类。结论此方法可对打印纸品牌进行有效区分。  相似文献   

3.
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   总被引:2,自引:0,他引:2  
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。  相似文献   

4.
目的 建立X射线衍射法(XRD)检验有机炸药的方法.方法 使用X射线衍射仪对有机炸药苦味酸(PA),太安(PTEN),黑索金(RDX),梯恩梯(TNT)进行测试分析.结果 准确测定出有机炸药的物质组成及结构.结论 该方法能够直接给出有机炸药的分子式及结构组成,定性准确,操作简便,可用于有机炸药的定性检测.  相似文献   

5.
目的研究元素分析对不同品牌猎枪弹丸的鉴别能力。方法应用X射线荧光光谱仪对30个弹丸样品进行Ph、Sb元素的半定量分析,并用T检验法对测试数据进行分析。结果同品牌猎枪弹丸的Pb、Sb元素含量无显著性差异,不同品牌弹丸的Pb、Sb元素含量有显著性差异。结论利用X射线荧光光谱仪对弹丸Pb、Sb元素的分析可对猎枪弹的品牌进行鉴别。  相似文献   

6.
无碳复写纸的X射线衍射分析   总被引:1,自引:0,他引:1  
通过对无碳复写纸原纸和显色涂层的X射线衍射分析,达到对不同厂家无碳复写纸区分的目的.  相似文献   

7.
目的研究油浸法和X射线荧光光谱法对汽车风挡玻璃的鉴别能力。方法应用油浸法对30个风挡玻璃样品进行折射率测试,并将所得数据进行t检验分析。对不能区分的样品再用X射线荧光光谱进行元素成分分析。结果30个样品共组成的435对中,折射率t检验在置信度959/5时区分427对,其余8对通过元素成分实现区分。结论折射率测试和元素分析相结合,可对常见汽车风挡玻璃进行有效区分。  相似文献   

8.
目的对红色印油印迹色料成分进行分析,研究确定印油印迹的种类区分方法,为侦查破案提供依据。方法采用超高效液相色谱法分析,以保留时间为主进行定性,对35种不同品牌的印油产品中色料成分进行区分。结果将印油印迹分为普通印油(印泥、原子印油等)、水性印油及光敏印油三类,建立了统一的UHPLC分析方法,其种类区分率达85%以上。结论通过印油印迹成分研究,最终区分印油印迹种类,可满足实际案件中对不同类型印油的鉴别区分。  相似文献   

9.
目的研究不同品牌透明胶带的区分方法。方法利用测厚仪对35种不同品牌透明胶带的厚度进行检验,并对所得数据进行统计分析。结果 35种品牌透明胶带组成的595组样品对中有458组可以区分,区分率为77.0%。结论厚度检验法能够在一定程度上区分不同品牌的透明胶带,厚度检验结果可与化学成分检验相互佐证,使得鉴定结论更加准确可靠,为法庭科学领域透明胶带物证的区分提供了一种预检验方法。  相似文献   

10.
刑事技术微量物证检验可能涉及各种各样的物证,这些物证的检验分析通常涉及比对检验、描述物证的性质、推断其来源或者对物证进行分类。XRD分析有很多优点,如需要样品量少,不破坏检材,准确地物相分析等,而准确的物相分析有别于其他的化学分析方法,其检验结果在法庭上能起到结论性作用。在很多情况下,XRD分析技术是其他分析方法无法替代的。当然,通常XRD检验必须结合其他分析手段(SEMEDS/WDS,XRF,FTIR等)才能发挥其独特的作用。XRD可分析的样品比较广泛,  相似文献   

11.
The rise in improved and widely accessible printing technology has resulted in an interest to develop rapid and minimally destructive chemical analytical techniques that can characterize printing inks for forensic document analysis. Chemical characterization of printing inks allows for both discrimination of inks originating from different sources and the association of inks originating from the same source. Direct analysis in real‐time mass spectrometry (DART‐MS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR) were used in tandem to analyze four different classes of printing inks: inkjets, toners, offset, and intaglio. A total of 319 samples or ~ 80 samples from each class were analyzed directly on a paper substrate using the two methods. DART‐MS was found to characterize the semi‐volatile polymeric vehicle components, while ATR‐FTIR provided chemical information associated with the bulk components of these inks. Complimentary data results in improved discrimination when both techniques are used in succession resulting in >96% discrimination for all toners, 95% for all inkjets, >92% for all offset, and >54% for all intaglio inks.  相似文献   

12.
目的分析假币票样上的印刷疵点,为串并假币机制版印制点提供科学依据。方法通过图文扫描和图象处理技术,获取假币票面上的印刷疵点信息,研究梳理不同票面上一致的疵点组合,寻找其与印版的相关性,继而推导与印制者的相关性。结果找到可以表征相同胶片版或PS版的不同冠字号码假币票样上一致的印刷疵点。结论可以通过图文扫描和图象处理手段得到印刷疵点特征。  相似文献   

13.
《Science & justice》2020,60(4):347-357
The potential of ATR-FTIR spectroscopy combined with chemometric methods is explored for the rapid and no-destructive forensic investigation of inkjet, laser and photocopier printed documents. The aim of the present study is to ascertain the source of origin of unknown printed documents, i.e., whether it belongs to the laser or inkjet or photocopier devices and also to visualize the intra-variations present in the same types of printed documents. It is observed that these printing inks contain polystyrene, bisphenol A, methyl acrylate and aromatic ethers as the main chemical constituents. The standard normal variate normalization is performed in order to eliminate the differences caused by the amount of toner powder/inks. The discrimination among printed documents is achieved by using chemometric methods including hierarchal cluster analysis and principal component analysis. Further, linear discriminant analysis is used to classify the unknown printed documents into its respective class of printing devices. The present methodology provides robust, non-destructive, reproducible, and simultaneous identification methods for printed documents.  相似文献   

14.
A new method for thermal desorption of small samples is presented. The method uses a solid phase microextraction (SPME) holder with the fiber removed. The sample-for example, an ink sample on paper-is simply placed inside the needle of the holder, where normally an SPME fiber is positioned. The thermal desorption is then performed on any kind of gas chromatograph in a manner similar to that for SPME analysis. The needle of the SPME holder penetrates the injector septum; the temperature of the thermal desorption is simply the temperature of the injector. No solvents or liquid nitrogen cooling are used. The paper sample is kept inside the holder needle during the analysis. After the analysis is completed, the sample is removed from the needle by pushing forward the steel wire inside the needle in the way normally used to perform sampling with the SPME fiber. The desorbed compounds were analyzed by gas chromatography with a flame ionization detector or by gas chromatography-mass spectrometry. The optimum temperature for desorption of ink samples on paper was 200 degrees C. The influence of the paper matrix is negligible at that temperature. Laboratories lacking the commercial device for thermal desorption can use this cheap device for the analysis of, for example, writing ink, printing ink, and inkjet ink samples on paper. Other types of samples can be investigated but the size of samples suitable for analysis is limited.  相似文献   

15.
目的运用激光显微共聚焦拉曼光谱仪对打印墨水的墨迹样品进行检验。方法采用514nm激发波长,测得EPSON、HP、CANON等3个品牌21种型号墨迹样品的拉曼光谱。结果根据拉曼峰位的异同,可将21种型号墨迹样品分为8大类。结论该方法可以快速区分常见不同种类打印墨水墨迹,为印刷文件的检验鉴定提供方法参考。  相似文献   

16.
A novel approach for the analysis of inkjet inks is being reported. A time‐of‐flight mass spectrometer, coupled with a Direct Analysis in Real Time (DART?) ion source (AccuTOF? DART?), was used to determine if inkjet inks from various manufacturers and models of printers could be reliably differentiated, characterized, and identified. A total of 217 ink standards were analyzed. As inkjet printing often involves the use of multiple colors (e.g., cyan, magenta, yellow, and black) to form an image or text, two different approaches to creating a library of standards and sampling methods were evaluated for implementation in a standard operating procedure. This research will show that a microscopic examination of the region of interest is requisite to identify what colors were utilized during the printing process, prior to comparing with known standards. Finally, blind testing was administered with 10 unknown samples to assess the validity and accuracy of the methodology.  相似文献   

17.
崔岚 《中国司法鉴定》2011,(5):57-58,61
介绍了丝网版印章的制作工艺,分析了丝网版印章印文特征的可变性和稳定性,总结了丝网版印章印文检验的方法,为司法鉴定实践中此类印章印文的真伪鉴别工作提供一定参考。  相似文献   

18.
3D printers are becoming increasingly efficient and economical, and thus more widespread and easily accessible to consumers and businesses. They have been used to print nefarious objects such as guns and suppressors. Previous research has documented the release of dust particles during the printing process; however, little has been written about the morphology and chemical features that define the dust emitted by these printers. This study was undertaken to recover, analyze, and identify the dust produced during the printing process in the context of forensic trace evidence analysis. Samples were collected from a variety of 3D fused deposition modeler printers, representing both consumer and commercial grade models. This work focused on printers that use thermoplastic filaments composed of acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), two of the most commonly used filament polymers. Swabs were used to collect dust within the printer chamber and then processed to isolate the dust particles. Particles produced from ABS filaments are most easily recognized via light microscopy through a combination of color, morphology, and fluorescence. The composition of these particles can be confirmed through analysis by either FTIR or Raman microspectroscopy. These methods can also be used to identify ABS fillers and pigments within the printer dust particles. In contrast, dust from PLA printers consistently contained finer, submicron-sized particles that could be observed by field emission scanning electron microscopy. Because the size of the particles precludes their identification using vibrational spectroscopy methods, pyrolysis-GC-MS was used to confirm the presence of PLA.  相似文献   

19.
目的建立化学显色法检验喷墨打印机字迹色痕的方法。方法选用不同的试剂或混合试剂,对22种不同品牌的喷墨打印黑色墨水的溶解性及与不同试剂的颜色反应进行观察。结果不同品牌的喷墨打印机黑色墨水的溶解性不同,与不同试剂作用会显现不同的颜色。结论化学显色法快速、简便,可用于现场的快速检验。  相似文献   

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