一种新型钢丝剪剪切痕迹特征及其检验

钢丝剪作为破坏线缆的一种工具，为最近几年才出现的新型工具。笔者通过实验研究，总结归纳出新型钢丝剪的结构特征及其痕迹特征，为钢丝剪痕迹检验提供重要的依据。     

利用铣纹痕迹数量和角度判断钢丝钳剪切位置

目的观察钳剪钢丝铣纹痕迹规律。方法用钢丝钳剪切铁丝,观察形成铣纹痕迹的特点和规律,并对铣纹痕迹数量和倾斜角度与钢丝钳剪切刃口位置的关系予以分析。结果钢丝钳刃口形成的铣纹痕迹数量和倾斜角度随刃口位置变动而发生相应变化。结论通过检测铣纹痕迹的数量和倾斜角度能可靠判断剪切刃口的具体位置,为制作样本选择刃口部位提供依据。     

通过痕迹认定肇事车辆

随着交通事故勘验技术的发展,物证技术在重特大交通事故现场勘验以及侦破交通逃逸案件中发挥的作用越来越重要.痕迹检验技术作为物证技术的一个重要分支,在认定肇事车辆中发挥着举足轻重的作用.交通事故中的痕迹是车辆与车辆、人体、道路等客体在路面上相对高速运动形成的痕迹,相对于其它类型案件有着自己的特点.交通事故中的痕迹分布范围广、造痕体和承痕体相对运动剧烈,形成痕迹的造痕体和承痕体大多都会发生形变.基于交通事故中痕迹形成的这些特点,交通事故中的痕迹检验难度是比较大的.但交通事故中车辆的特殊结构形成的印压痕迹、车辆轮胎、摩托车车篮等造痕体在灰尘等介质作用下在人体的衣服等表面形成的印压痕迹都可以很好反映造痕体的外部结构特征,从这些痕迹反映出造痕体的外部结构特征可以寻找和认定交通肇事车辆.     

用铝箔胶带复制弹头上的膛线痕迹

本文对铝箔胶带复制的弹头膛线痕迹样模进行了现察比较,结果表明:用该胶带复制的样模,塑形细腻准确,长久不变形;痕迹表面平整,易调灯光角度,痕衬反差适中;一次现察多条膛线痕迹,明显提高检验效率.     

犯罪现场重建

犯罪现场是指犯罪行为实施后，引起受害人、客体物发生变化的统—体。犯罪行为、犯罪工具造成特定的物质变化（被害对象直接发生变化，现场客体物表面发生变化．现场客体物增加或减少的变化，现场客体物位置和组合形态发生变化）．产生相应的遗留痕迹（形象痕迹、印象痕迹、心理痕迹、电磁痕迹），痕迹与行为存在必然的因果关系。     

球形表面手印胶带纸提取方法

如何提取球面客体表面已通过粉末方法显现的手印痕迹,是痕迹检验工作的一项重要研究内容。笔者经多次摸索实验表明,只要改进胶带纸的粘取方法,就可以有效地提高球面客体表面手印的提取效果,提取到完整或相对完整的手印痕迹。     

灵活运用定向反射原理拍照指印痕迹

刑事案件现场勘察中，经常遇到光滑客体表面疑难指印痕迹的拍照提取问题。由于此类客体表面的疑难痕迹在一般漫射光照条件下，反差非常微弱，甚至很难观察到，所以只有在入射光垂直或近似垂直客体表面，且光亮度较强、光照面积较大时，才能发现较为清晰完整的指印痕迹。实践证明，以定向反射原理设计的同轴光摄影仪、近轴光摄影仪都是解决上述难题很有效的方法，但在实际应用中，又发现它们都存在一定的局限性，即对痕迹表面积较大且不规则的强反光光滑客体（如弧形、多面、多棱的强反光瓷制品、搪瓷制品、电镀钢铁制品以及漆类制品）就无能…     

利用导线表面特征作整体分离检验

本文介绍了利用现场导线表面特征(加工痕迹和使用过程中形成的痕迹)与嫌疑导线拼接检验,直接进行认定或排除。     

运用Photoshop软件进行形象痕迹检验

近几年来随着数字图像技术的快速发展,我们在实践中也逐渐将Photoshop运用于刑事科学技术领域的形象痕迹检验,运用电脑设备借助于数码相机或扫描仪,可以在不用显微镜等放大设备的条件下对指纹、足迹、工具痕迹、枪弹痕迹、文件材料进行直接检验,用于痕迹任意倍放大,方向、角度的调整处理,痕迹特征的描述、标注、比对、分析认定,并能直接打印出比对结果。笔者根据自己学习、使用Photoshop进行形象痕迹检验鉴定的实践,现以砍切工具痕迹检验为例将检验方法介绍如下。1检验操作方法根据工具痕迹检验的理论,利用成痕客体表面上反映成痕工具刃口…     

近轴光摄影仪的应用

近轴光摄影仪对拍照提取遗留在平面光滑或比较光滑物体表面上的疑难痕迹物证(特别是带有汗液成份的指掌纹)有很好的效果,较好地解决了长期以来对遗留在这类客体上的痕迹物证在拍摄时需配近垂直光的难题.     

Application of atomic absorption spectroscopy for detection of multimetal traces in low-voltage electrical marks

Application of atomic absorption spectroscopy to detect multimetal traces in injured skin is a promising tool for investigation of fatalities caused by electrocution. The present paper is aimed at testing the reliability of this method for metal traces detection in electric current marks and is focused on study of peculiarities of metal penetration into the skin exposed to a current impact. Bare aluminum wire, tin-lead coated copper multistrand wire, and zinc-plated steel rope were used to make electrical marks on pig skin. It is demonstrated that amount of copper, zinc, lead, and iron may serve as statistically reliable indicators for the type of wire, which caused the electrical mark, in spite of the background content of these metals in the skin without injury. Different penetration rates for different metals contained in the wire inflicting an electrical mark were observed.     

Identification of wires and the cutting tool by scanning electron microscope

The cut ends of aluminium and copper wires made by different pliers have been compared under the scanning electron microscope to correlate the two pieces of a wire and to identify the cutting tool. The mechanism of producing the cut ends has been discussed. Matching of extrusion marks and correspondence of breakages at the edges of the cut ends were observed. Correspondence between the fine striations was observed on the opposite faces. These features are put forward for assigning a cut wire to a source.The ends produced by repeatedly cutting a wire by the same portion of the edge of a pair of pliers have been compared. It was found that the striations and fracture zones were reproduced on the respective surfaces of the consecutive cut ends. To identify the cutting tool in wire theft cases, it is suggested that the trial cut ends can be made by cutting the wire with successive portions of the edge of the suspected tool and compare the surface features with that on the questioned ones.     

6种现场常见断线钳加工特征的研究

目的研究不同品牌断线钳加工特征的差异性及痕迹反映与加工特征之间的关系。方法以6种现场常见断线钳为研究对象,首先观测断线钳的刃顶厚度、刃片咬合间隙、刃侧铣纹宽度和铣纹间距等参数,然后观测剪切断头痕迹的立顶高度、立顶厚度、刃侧铣纹印痕宽度和铣纹印痕间距等参数,并用SPSS统计软件进行处理。结果 6种品牌的断线钳加工特征存在差异,断头痕迹可以稳定地反映该差异。结论可利用断头痕迹特征推断断线钳种类。     

The Identification of a Steel Mold’s Marks on Fake Drug Bottles

Plastic bottles are commonly encountered in drug cases where they are used as packaging materials and produced with polymers. However, to the best of our knowledge, systematic studies on the evidential values of medicine bottles have not been carried out. Therefore, it is difficult practically to determine if it is possible to identify whether the plastic bottles are manufactured with the same steel mold by comparing the manufacturing marks on plastic bottles. This paper reports the successful attempt of the authors in establishing a definite relationship between three different medicine bottles with a steel mold recovered from suspects. Fourier transform infrared spectroscopy (FT-IR) was used to characterize the chemical composition of submitted medicine bottles, and then some physical characteristics (viz., total length, length, and diameter of different parts) and the manufactured marks on these bottles were examined. The results showed that the linkage of the medicine bottles to a steel mold was successfully established using the similarities in physical characteristics and manufacturing marks. In the process, the FT-IR was only complementary in the identification process. The individual characteristics of plastic medicine bottles included the imperfections and striated impressions that were produced by the grinding patterns on the inner surface of a steel mold.     

An unusual case of high-voltage electrocution of a truck driver due to inadvertent contact of the truck with an overhead wire

Electrocution deaths are mostly accidental. However, reconstruction of events in unusual electrocution death is challenging. This article reports an accidental death due to electrocution in a highly unusual circumstance, in which a truck driver reversing his vehicle was electrocuted when his truck inadvertently touched an overhead high-voltage wire. The electric injury marks were present over the sole of the right foot. The scene investigation revealed that the high-voltage wire was loose and was below the level of the prescribed height. The truck was passing over an elevated area made up of dirt and stone. The interior of the cabin of the truck revealed a few non-insulated metallic areas over the floor of the truck, between the accelerator and the brake, which were attributed as the sources of entry of electricity into the body. The electric injury marks were different than those usually seen in high-voltage electrocution as there was an intermediate object (truck) involved, and the contact period between the truck and the electric wire was minimal. This fatality was attributed to the non-proper insulation of the interior of the truck, the negligent driving of the truck driver over the elevated surface, and the loose high-voltage wire without proper maintenance.     

对女性耻骨联合分娩疤痕的研究

本文观察了90例女性耻骨联合。其中50例已分娩妇女耻骨联合背侧近缘的骨面上、联合面上端与骨嵴、联合面下与骨嵴、腹侧斜面和斜坡等部位，可检见不同程度和形态的疤痕。96％在耻骨背侧近缘的骨面上出现疤痕；76％在耻骨联合上端与骨嵴部位出现疤痕。40例未生育的女性耻骨联合上，除3例在背侧近缘的骨面上，出现类似分娩者疤痕外，其他3个部位均未见类似分娩者疤痕。本研究提示，女性耻骨联合出现不同程度和形态的疤痕，对判断无名女性尸骨在生前有无分娩史，具有一定价值。在五个实例中应用此法判断取得了满意结果。     

Restoration of engraved marks on steel surfaces by etching technique

It is known that restoration of erased engraved identification marks on the engine and the chassis of a car or on a firearm has low success rate. Unlike stamping, engraving on a metal surface leaves no pronounced, permanent subsurface deformation in the crystalline structure, also called dislocation that can be revealed by suitable methods. Hence, the current research work investigated whether metallographic reagents used in the restoration of stamp (compression) marks could be applied to recover engraved marks on steel surfaces and also to establish the sensitivity and effectiveness of some of these reagents for the restoration of the marks. Experiments were conducted by mechanically engraving alphanumeric characters on several steel plates using a computer controlled engraving machine called Gravograph. The markings were later erased from the above steel plates by removing the metal in stages of 0.01 mm through 0.04 mm below the bottom of the engraving. Several plates were thus prepared wherein each one had been abraded to a specific depth. Then eight metallographic reagents were tested on each one of the above erased plates using a swabbing technique. The results had shown that while most of the reagents were able to restore marks up to certain levels of erasure, the reagent 5 g copper sulphate, 60 ml water, 30 ml concentrated ammonium hydroxide and 60 ml concentrated hydrochloric acid restored marks erased to a depth of 0.04 mm below the engraving depth, thus presenting itself the most sensitive reagent. Quite significantly, the above reagent was also able to decipher successfully the original engraved marks that had been erased and engraved with a new number, or obliterated by centre punching. The results of this research work should benefit the forensic practitioners engaged in the serial number recovery on vehicles, firearms and other objects.     

扫描电镜下缢沟的形态特征

作者用光镜和扫描电镜对縊沟进行对比观察,得出如下结论:(1)扫描电镜下縊沟组织的改变具有较恒定的特征,出血及纤维蛋白检出率远较光镜为高;(2)在光镜下生活反应不明显的生前缢沟,在扫描电镜下其表面及断面均可见红细胞及纤维蛋白形成,并包裹红细胞。縊沟部位胶原纤维之间可见散在大小不等的圆球形脂肪样小滴。缢沟部位肥大细胞的形态改变,有助于生前与死后缢沟的鉴别诊断。     

电缆电线的检验

研究电缆电线护套表面线条痕的形成原因及质量,初步探讨电缆电线的检验方法.