Use of lycode powders for the examination of documents partially written with erasable ball point pen inks

It was discovered by change that lycode powders adhere to erasable ball point pen ink strokes. A study of this phenomenon was carried out to determine what type of inks reacts physically with lycode powders. A further evaluation was made to learn if this effect continued after the erasable ink became indelible. It was also found that obliterated erasable ball point pen ink can be read by applying lycode powders and that the powders react in a similar way with typewriting from a conventional inked typewriter ribbon. Treatment in this case is completely non-destructive since the lycode powder can be wiped off the paper surface.     

An investigation into the use of a portable cyanoacrylate fuming system (SUPERfume®) and aluminum powder for the development of latent fingermarks

Abstract: Few techniques offer “in situ” methods of friction ridge skin mark development. “In situ” development reduces mark transportation, degradation, and often cost. The effectiveness of cyanoacrylate fuming using the SUPERfume^® and dusting with aluminum powder for latent fingermark development on several nonporous surfaces, stored in various temperature environments for time periods up to 52 weeks, was investigated. Five thousand and four hundred latent fingermarks were deposited under controlled conditions and graded. The results suggested that cyanoacrylate fuming (SUPERfume^®, Foster and Freeman, U.K.) was more effective at developing latent fingermarks on textured and smooth plastic surfaces and for marks stored in temperatures of 37°C, whereas aluminum powder was more effective on glass, enameled metal paint, and varnished wood, and for storage temperatures below 20°C. There were no significant benefits to using either technique for marks older than 24 h, but it was possible to develop fingermarks following 52 weeks of storage using both techniques.     

复方守宫散中铅、镉、铜含量分析

目的：测定抗肿瘤药物复方守宫散中微量金属元素铅（Pb）、镉（Cd）、铜（Cu）的含量.方法：采用湿法消化,火焰原子吸收分光光度法测定.结果：复方守宫散中含金属元素Pb、Cd、Cu,含量高低依次为：Pb〉Cu〉Cd.结论：复方守宫散每日服用量中Pb、Cd、Cu含量均远低于人体正常摄入量,属安全用药范围.     

开拓汗潜手印显现的新领域

系统论述了JHF-系列荧光粉末和JHC-系列荧光磁性粉显现汗液指纹的理论基础和主要特点,比较了与金属粉末显现手印的不同效果,列举了在不同客体和不同留痕条件下显现的汗潜手印的方法.     

开设多波段光源发现痕迹的实验

多波段光源已广泛应用于痕迹检验、现场勘察等领域,是公安机关侦破案件的一个重要武器。公安院校刑侦、刑技专业的学生,通过做多波段光源发现痕迹的实验来掌握该项技术很有必要。     

EDX、XRD法定性分析混合火药的主要成分

目的建立检验自制混合火药方法。方法用扫描电镜、X射线衍射仪,测定自制混合火药的主要成分,结果准确可靠。结果既可测定火药成分,还可区分石墨晶片和植物性炭。结论两种方法可用于火药鉴定。     

几类特殊客体上指纹的树脂提取法

在犯罪现场上经常会遗留犯罪嫌疑人的指纹,遗留指纹的客体种类繁多,有几类特殊客体上的指纹较难提取,如粗糙客体、人体皮肤、曲面客体等。文章通过实验研究发现,磁性粉末刷显法与树脂制模法配合使用,可以很好地提取这些特殊客体上的指纹,树脂制模提取指纹的方法为指纹的提取提供了一条新途径。     

“三鹿奶粉”系列案定性探疑

"三鹿奶粉"系列案涉及的、含有三聚氰胺的所谓"蛋白粉"是有害物质而不是有毒物质,添加者故意将其添加到原牛奶中并卖给"三鹿集团"的行为,在性质上属于生产、销售有害食品。制造并销售"蛋白粉"的行为不应当如法院判决的那样构成以危险方法危害公共安全罪,而应当与添加者的行为构成生产、销售有害食品罪的"连锁共犯"。"三鹿集团"的行为,应当以2008年8月1日检测报告出具明确结论为界分为两个阶段:在前一阶段,其直接负责的主管人员构成重大责任事故罪,在后一阶段,"三鹿集团"的行为在性质上属于生产、销售有害食品,与生产销售伪劣产品罪存在法条竞合;根据《刑法》第149条关于择一重罪处罚的规定,应按第140条的规定构成生产、销售伪劣产品罪;对"三鹿集团"直接负责的主管人员两个阶段的罪行应当数罪并罚。     

纳米粉末显现水果和蔬菜表面手印

目的研究纳米粉末显现水果和蔬菜表面的手印。方法纳米Fe3O4粉末的显现方法同常规磁性粉末;纳米ZnO粉末则是撒粉于可疑表面,然后用吸耳球轻轻吹掉多余的粉末直到手印显出,利用多波段光源,在紫外一可见光范围内拍照;并与松花粉显现法比较。结果纳米Fe3O4粉末可以清晰显现4种检材表面的手印;纳米ZnO粉末可显现除土豆之外的3种检材表面的手印,尤其显现西红柿表面手印的效果最好;与松花粉相比,纳米粉末显现的手印纹线流畅、细腻,细节特征清晰。结论利用纳米粉末可以有效显现水果蔬菜表面的手印,显出的纹线在紫外－可见光范围内拍照均可以得到反差较大的影像。     

Simulating transfer and persistence of a chemical marker powder for Lycopodium clavatum spores

In this research a chemical marker powder, based on Lycopodium clavatum spores, was studied to determine its transfer and persistence on a T-shirt. Such chemical marker powders are used to provide evidence that a person has handled a covertly marked object, such as a drug package. The powder was found to transfer readily between a marked item and the person handling it. The powder was found to persist on a T-shirt for up to 13 h; however, there was only a very small amount of powder remaining at this time. The rate of loss of the L. clavatum spores was found to follow a decay curve. The largest decrease in spores from the T-shirt was seen in the first 2 h after the marked item had been handled.