SWP荧光剂熏显油脂手印方法的初步研究

目的建立SWP荧光剂熏显油脂手印的新方法。方法选取12中常见客体,根据试验需要分别捺印油脂手印144枚和油汗混合手印100枚,用多功能手印显现柜加热升华SWP荧光剂,熏显渗透性和非渗透性客体上的手印。结果油脂手印显现出了142枚,显出率达到98．6％;油汗混合手印,非渗透性客体共显出100枚,显出率达到100％,渗透性客体共显出95枚,显出率达到95％。结论SWP荧光剂对油脂手印的显现效果良好,可与“502”同时熏显,且不影响茚二酮等其他方法的进一步检验。     

碘熏显现热敏纸上的汗潜手印

热敏纸作为一种特殊的客体,其传统显现普通纸张汗潜手印的显现方法,如(硝酸银显现法、茚三酮溶液法、DFO法等) ,都不能有效显现热敏纸上的汗潜手印。热敏纸遇到有机溶剂,药膜面上会产生黑色污染背景,影响指纹显现,甚至使整个膜面变黑,上面的手印消失。直接加热法显现热敏纸潜手印时,显现温度难以掌握,易污染检材,只能显现热敏纸膜面上的手印,背面的手印没法解决,对有效显现热敏纸上的手印有很大的局限。而碘熏法能克服上述不足,有效的显现热敏纸上的潜手印,此方法操作简便,显现效果较好,不仅能显现新鲜手印,还能显现保存较好的热敏纸上的…     

碘热升华喷枪显现潜手印的应用研究

本文提出一种以石英灯为加热器的碘热升华喷枪显现潜手印的新方法。实验表明,该技术方法操作简便,适用范围广,手印显出率高,尤其是显现遗留在墙面、本色铝合金表面、UPVC表面的潜手印效果明显。     

影响真空镀膜显现手印效果的因素分析

目的考查真空镀膜技术在手印显现方面的应用。方法从影响真空镀膜法显现手印的因素展开,重点分析了喷镀距离、金的用量、客体悬挂角度、锌的蒸发电流和时间等对手印显现的影响。结果条件优化后可以增强手印纹线的立体感,改善金膜、锌膜在手印纹线和客体背景的分布情况,使显出的手印纹线反差明显。结论确定真空镀膜显现常见非渗透性客体上汗潜手印的最佳操作条件。     

PAMAM G7.0的制备及在非渗透性表面手印显现中的应用

目的探索一种非渗透性表面手印显现的新方法。方法根据现有方法合成第七代聚酰胺-胺（PAMAM G7.0）树形分子材料,并使用荧光光谱法对产物进行荧光测试;将合成材料对多种客体表面、不同遗留时间的手印进行显现,并将显现结果与粉末法和传统的荧光染料法进行比对。结果实验表明该荧光材料在365nm光激发下可以发出较强的可见荧光;与粉末法和传统的荧光染料法相比,PAMAM G7.0可以同手印残留物进行高选择性结合,手印纹线与背景之间的反差大。结论PAMAMG7.0可以有效地显出非渗透性客体表面的手印。     

“502”加膜一染色法显现油质手印

目的探索方便快捷并有效的油质手印显现方法。方法用“502”熏显常见玻璃、粗糙皮革等不同客体上不同遗留时间的油汗手印和多油手印,加染后用透明胶带粘取。结果显现了30天左右大多数非渗透性客体上的油质加层手印,10天左右渗透性客体上的油质渐层手印。结论本方法适用于油质加层手印及部分油质渐层手印的显现,显出手印清晰,流畅,不破坏手印。     

荧光黄湿粉显现手印方法的初步研究

目的研发一种具有荧光特性的黄湿粉,以提取遗留在不同客体上的不同种类的手印。方法在100mL温水中加入适量的表面活性剂,溶解后加入100g荧光黄颜料,选用不同种类客体及不同种类物质手印进行显现实验,比较显现效果;结果遗留在光滑非渗透性客体及半渗透性客体表面的汗潜、油潜手印,显出的手印纹线流畅、反差强、荧光强;结论荧光黄湿粉可适用于光滑非渗透性客体及半渗透性客体表面新鲜或较新鲜汗潜手印、油潜手印及血潜手印的显现。     

浅色调湿粉显现手印方法的研究

目的探索新的手印显现方法,祛除传统手印显现方法对使用者的健康危害;方法用浅色调湿粉采用不同操作对不同客体表面手印、不同物质手印及不同遗留时间手印进行显现,通过显现效果的比较,得出湿粉显现手印的适用范围、最佳操作方法及其显现效果;结果显出的手印清晰、流畅,与背景反差强;结论该方法适用于光滑非渗透性客体表面及潮湿或粘性表面的汗潜、油潜、蛋白手印的显现,使用方便有效。     

京尼平与茚三酮显现手印方法的比较研究

目的对京尼平与茚三酮两种手印显现方法进行综合评价。方法用两种方法显现不同遗留客体上不同遗留时间的手印,并对显现效果、显出手印的稳定性及纸张字迹油墨扩散等现象进行考察。结果京尼平与茚三酮有着相似的的显现原理、适用范围和熏显条件,但在显现效果、显出手印稳定性、试剂成本和安全性能方面存在差异。结论京尼平相比茚三酮方法更安全、绿色环保、显出的手印稳定性更强。     

真空镀膜与“502”熏显法显现非渗透性客体上汗潜手印的比较研究

目的探索真空镀膜手印显现技术,提高现场潜在手印显现率。方法通过真空镀膜与＂502＂熏显法显现常见非渗透性客体上汗潜手印的对比实验,比较二者显现效果优劣。结果真空镀膜法对于显现常见非渗透性客体上的新鲜和陈旧汗潜手印都有着明显的优势。结论真空镀膜是一种更为灵敏的非渗透性客体手印显现方法,是现有手印显现方法的重要补充。     

运用“502”粘合剂显现长时间潜在手印的研究及应用

本文对“502”粘合剂显现手印法进行适当的技术改进,通过显现一起潜在手印遗留时间长达一年以上罕见案例的实际应用,并对操作方法和影响因素等方面进行讨论,以拓宽“502”粘合剂显现潜在手印的应用范围.     

The Influence of Selected Fingerprint Enhancement Techniques on Forensic DNA Typing of Epithelial Cells Deposited on Porous Surfaces

Fingerprints deposited at crime scene can be a source of DNA. Previous reports on the effects of fingerprint enhancement methods have focused mainly on fingermarks deposited in blood or saliva. Here, we evaluate the effects of fingerprint enhancement methods on fingerprints deposited on porous surfaces. We performed real‐time quantification and STR typing, the results of which indicated that two methods (iodine fuming and 1,2‐indanedione in ethyl acetate enhancement) had no effect on the quantity of DNA isolated and resultant STR alleles when compared to control samples. DNA quantities and allele numbers were lower for samples enhanced with silver nitrate and 1,2‐indanedione in acetic acid when compared to control samples. Based on DNA quantity, quality, and observable stochastic effects, our data indicated that iodine fuming and 1,2‐indanedione in ethyl acetate were the preferred options for the enhancement of fingerprints on porous surfaces.     

“502”胶液体显现潜手印技术的研究

目的研究探索"502"胶溶液显现手印的方法.方法以石油醚为分散剂,添加对苯二酚作为显现增强剂,配制"502"胶显现液.结果能够显现非渗透客体上油质加、减层手印、加减层混合手印及普通汗潜手印,其显现效果与"502"胶熏显法非常相似.结论该方法具有方便、快捷、灵敏等特点,是"502"胶显现手印技术的重要补充.     

The recovery of latent text from thermal paper using a simple iodine treatment procedure

Faded, or actively removed text on thermally printed paper samples may be enhanced and retrieved through the use of a simple iodine fuming procedure. The recovery of printed documentation evidence in this fashion is neither affected by prior fingerprint enhancement techniques (such as ninhydrin or DFO), nor by sample age. This method allows, for the first time, evidence to be obtained from completely faded thermal paper samples (receipts, for example) as well as allowing deliberately removed printed text (a consequence of solvent washing pre-treatment in latent fingerprint enhancement procedures) to be recovered.     

Development of latent fingermarks on thermal paper: Preliminary investigation into use of iodine fuming

Thermal paper finds its extensive use in the modern day life and could act as a vital piece of physical evidence carrying latent fingermarks. A large number of citations are available in literature suggesting various techniques to develop these marks but all are suffering with one or the other drawbacks such as complex and cumbersome procedure, pre- or post-treatment, background coloration and efficiency to develop aged fingermarks. In present study, a very simple and novel method involving iodine fuming has been suggested to develop fingermarks which were not only permanent but also without any background coloration. The suggested method does not involve any pre- or post-treatment of the substrate and was able to develop very old fingermarks (upto >1 year). In this study an attempt has been made to explain the reaction mechanism of the process. In case of different types of thermal papers, presence of different substituents on leuco dye (lactone ring) structure resulted in development of different colored fingermarks upon reaction with iodine. Sebaceous material laden marks have been found to be more intensely developed as compared to eccrine marks, and the difference was more pronounced in case of aged fingermarks.     

Development of Latent Fingermarks on Surfaces of Food‐A More Realistic Approach

Latent fingermark developing methods from food (mandarin, egg, banana, apple, potato, carrot, eggplant, onion, bell pepper, and tomato) surface has been studied by 10 methods, including powdering method, small particle reagent method, and cyanoacrylate fuming method. The foods were stored under two conditions (room temperature and refrigerator) before fingermark deposition and aged for 2, 24, 48, and 72 h before fingermark development. In most of the food surfaces used in this study, cyanoacrylate fuming with 80% relative humidity was superior to the powder or small particle reagent methods. The quality of the fingermarks varied depending on the storage conditions before the fingermark deposition (in the refrigerator or at ambient temperature) and the time elapsed since the fingermark deposition. However, the storage conditions before the fingermark deposition and the time elapsed since the fingermark deposition did not show any correlation with the quality of the fingermark.     

新型荧光502粉末与502胶＋荧光染色显现潜在手印的比较

目的对新型荧光502粉末显现非渗透性光滑客体表面潜手印的一步荧光502显现新技术和传统502胶水熏显＋荧光染料染色显现手印技术进行比较研究。方法比较实验研究,对荧光502粉末和502胶水使用同一自动熏显柜先后进行熏显,荧光502粉末熏显结束后直接在蓝光灯下激发进行观察和拍照;502胶水在熏显完成和聚合物完全固化后使用罗丹明6G和BBD溶液进行荧光染色,再进行光致荧光照相。结果一步熏显和二次染色的显现效果基本相同,但两者的显现效果也因检材性质和遗留时间的不同而存在一些差别。结论新型荧光502粉末可以作为一种显现非渗透性光滑客体表面上潜手印的常用方法,尽管新方法对某些客体的显现效果并不好,但对大多数客体来说,其显现效果并不弱于二次染色的方法,并且使用新型荧光502粉末进行一步熏显不会引入有机溶剂,不会引起502聚合物的溶解或造成破坏,确保了纹线及其细节特征不被损坏,也避免了染色后因漂洗不当使手印纹线被冲掉的可能,还不会破坏脱落细胞等生物检材。     

Preliminary efficiency evaluation of development methods applied to aged sebaceous latent fingermarks

Latent fingermarks are important trace evidence found in crime scenes mainly used for identification purposes. Once deposited, the composition of samples changes over time influencing the efficacy of latent fingermark development methods. In this sense, the aims of this work were to characterize the fatty acid (FA) profile of sebaceous latent fingermarks by GC–FID and to preliminarily evaluate the development efficiency of enhancement methods (powder dusting, iodine fuming and silver nitrate method) in a 30-day period of aging under controlled parameters of temperature, photoperiod and humidity. Results showed that myristic (7.51 ± 0.76% − 13.39 ± 1.26%), palmitic (35.91 ± 1.07% − 40.81 ± 2.52%), stearic (6.67 ± 0.36% − 9.13 ± 0.36%) and oleic (18.08 ± 0.25% − 20.93 ± 0.26%) acid varied significantly (p < 0.05) over the 30-day period of analysis. Regarding development efficiency, fluorescent orange powder and the silver nitrate method also increased their efficacy to develop latent fingermarks over time while the iodine fuming method decreased its efficiency. Silver black powder had constant efficacy in the tested period. Changes in the constitution of sebaceous marks possibly influenced the development efficiency of enhancement techniques. This knowledge is important to better understand the kinetic of aging and its influence on the development method.     

“502”真空熏显手印技术的应用现状

在我国,“502”加温加湿熏显手印技术已广为普及,但“502”真空熏显手印技术人们了解很少。本文通过介绍“502”熏显手印技术的发展,着重介绍真空熏显方法的特点。