新型亲油性纳米二氧化硅粉末在手印显现中的应用

目的 比较新型亲油性纳米二氧化硅粉末显现手印的效果.方法 应用亲油性纳米二氧化硅粉末与现场勘查箱内金粉、银粉和黑色磁性粉显现非渗透性客体表面油汗混合手印,并在自然光下观察比较显现效果.结果 亲油性纳米二氧化硅粉末显现出的手印图像纹线清晰连贯,背景反差好.结论 亲油性纳米二氧化硅粉末显现手印具有一定的优势.     

4种粒径的纳米氧化锌粉末显现指印效果的比较

目的比较4种粒径纳米氧化锌粉末显现指印的效果。方法应用上述粉末显现不同类型指印并分别于自然光和紫外光下观察比较显现效果。结果不同粒径粉末显现指印于自然光和紫外光下显现效果和发光颜色不同。结论针对背景颜色和指印类型选用不同粒径粉末。     

微观视角下湿度对粉末显现手印影响规律探究

目的微观视角下探究湿度对粉末显现手印的影响规律。方法利用扫描电镜微观成像技术,观察分析不同湿度下粉末的微观形态、粉末显现不同湿度下手印的微观形态、粉末显现不同方法处理高湿度手印的微观形态。结果黑磁粉、金粉、银粉分别在相对湿度50%、30%、50%时开始出现吸湿结球现象,随湿度增加,粉末吸湿结球程度加剧,且三种粉末中金粉和银粉的吸湿结球程度最为严重;对不同湿度下手印显现,黑磁粉从相对湿度50%(金粉为30%、银粉为50%)的手印开始,随湿度增加,手印乳突花纹和小犁沟位置处粉末颗粒增多,纹线模糊,乳突纹线与小犁沟难以分辨,三种粉末中黑磁粉显现手印的纹线清晰程度最高;95%湿度下手印经在50%相对湿度环境中静置4h或吹风机吹干10min后进行粉末显现,纹线变清晰。结论1)湿度对粉末和手印都有影响,其中黑磁粉显现手印适用湿度范围为相对湿度50%以下(金粉为30%以下、银粉为50%以下);湿度影响程度排序:金粉>银粉>黑磁粉;2)降低手印所处环境湿度、加快手印表面空气流通均可减弱高湿度对粉末显现的影响。     

基于PolyCyano UV粉末显现手印的新技术

目的介绍1种新型PolyCyano UV粉末显现非渗透性光滑客体表面潜手印的新技术。方法选取多种常见客体,由志愿者在客体上捺印指印,将PolyCyano UV粉末加热至230℃使其升华,待该粉末在手印纹线上聚合后使用长波紫外线照射若干时间,然后在蓝光激发下使用滤色镜观察并拍照。结果绝大部分非渗透性光滑客体表面上的潜手印均有很好的显现效果,尤其是对浅色或白色客体有十分明显的荧光效果,对陈旧手印也有较好的显现效果。结论该方法熏显操作简便、显现时间短、无需二次染色增强、不破坏生物检材、显现效果明显,适合推广使用。     

手印显现经验点滴

在现场手印显现中 ,经常遇有一些条件不好的手印 ,对解决这类问题 ,笔者积累了一些经验。介绍如下。1　陈旧性汗潜手印的综合处理2 0 0 0年 2月 10日 ,西安市某区发生一起拦路抢劫杀人案 ,分局技术人员勘察现场时 ,提取一个不锈钢口杯 ,用铜粉刷显出少量指印外围线 ,看不出纹型 ,无比对条件。一个月后 ,送到我处请求协助处理。受理此案后 ,笔者从指印纹线稀少且浅淡的情况分析判断出指印较为陈旧 ,应用“5 0 2”熏显法 ,于是进行重新处理。先用干净棉球 (药棉 )将杯上附着铜粉轻轻擦掉 ,然后用“5 0 2”胶熏显 (冷熏 ) ,经过冷熏后 ,原有的…     

用磁性粉显现灰尘手印

笔者通过长期的工作积累和实践，总结出对于渗透性光滑客体上遗留的薄层、较新鲜灰尘手印，用磁性粉显现效果较理想，方法简便，消耗小，显现的手印纹线清晰，易提取，保存时间长，是一种提取灰尘手印行之有效的好方法。现就此类手印的提取方法、步骤做一介绍。     

表面粗糙的客体上汗潜手印的显现

手印作为证据之首，在侦察破案中起着证实犯罪和认定罪犯的重要作用，在现场勘查过程中能否提取到条件比较好的手印，在很大程度上决定着以后检验鉴定工作中能否认定罪犯、证实犯罪。但是在许多情况下，由于受到手印遗留客体表面条件的限制，使我们在很多表面比较粗糙的客体上采用常用的一些方法（如用粉末刷显、或用“５０２”胶熏显等）所提取到的手印条件很差或者根本就提取不到手印，使人们失去了许多破案的良机。为了能更好的显现出表面比较粗糙的客体上的汗潜手印，笔者经过多次实验，用“LL７０１”闪电红荧光粉末成功地显现出了几…     

利用CdSe巯基乙酸溶液显现水浸客体表面潜手印

目的研究水浸客体表面潜指纹的显现方法;方法利用CdSe巯基乙酸溶液显现被水浸泡过的黄色封箱胶带、黑色塑料袋、玻璃等常见非渗透性客体上的潜手印,讨论影响水浸非渗透性客体上潜手印显现效果的各种因素,并与传统方法进行比较,初步探讨了CdSe巯基乙酸溶液显现水浸非渗透性客体表面潜手印的方法;结果使用巯基乙酸包覆CdSe纳米复合材料显现潜在手印,使每分子纳米复合材料外表包覆足够数量的羧基,则可以提高它同手印残留物的结合能力,从而得到更高清晰度、更高分辨率的手印显像;结论巯基乙酸包覆CdSe纳米复合材料可以很好的显现水浸塑料、胶带等表面潜指纹。     

纳米二氧化钛荧光粉末显现潜在手印研究

目的使用荧光染料包覆纳米二氧化钛颗粒,制备具有荧光效果的纳米二氧化钛粉末材料,并探索应用纳米二氧化钛荧光粉末显现潜在手印的方法。方法使用实验室合成的二酰亚胺染料与纳米二氧化钛微粒按照一定质量比混合制备形成荧光粉末,通过扫描电子显微镜对其进行表征,观察颗粒结构特征。在玻璃、瓷砖、透明塑料片、彩色塑料包装、易拉罐5类非渗透性客体上捺印手印,观察纳米二氧化钛荧光粉末对不同非渗透性客体上新鲜潜手印的显现效果。分别在5种客体上制作遗留时间为1、4、7、15d的手印样本,考察遗留时间对纳米二氧化钛荧光粉末显现自然陈旧手印效果的影响。将新鲜手印置于标准大气压100℃条件下分别加热1~72h,使用纳米二氧化钛荧光粉末显现,考察其对高温老化手印的显现效果。结果纳米二氧化钛荧光粉末为粒径100~200nm的圆形颗粒;在蓝绿光激发下可发出较强的荧光,能显现多种非渗透性客体上的新鲜手印,与背景反差明显并且能显著降低复杂背景对手印纹线的影响;显出新鲜手印中80%以上具有鉴定条件。纳米二氧化钛荧光粉末对遗留15d以内的陈旧手印仍具有较好的显现效果。100℃高温环境对手印显现效果没有明显影响。结论纳米二氧化钛荧光粉末经济、环保,显现操作简单,易于推广。     

纳米CdSe增强“502”胶显现新鲜手印方法研究

本文利用纳米CdSe溶液显现了白色塑料、塑钢上面的油脂手印,比较了该试剂和传统试剂的增显效果,初步探讨了纳米CdSe溶液增强“502”胶显现手印的应用前景.     

Techniques for fingerprint recovery on vegetable and fruit surfaces used in Slovenia — A preliminary study

An examination was conducted to investigate whether certain dactyloscopic powders and reagents can recover latent fingerprints on vegetable and fruit surfaces (apple, banana, tomato and potato). Two fingerprint powders, Swedish Soot powder mixture (Swedish Black), Silver Special powder and cyanoacrylate fuming (CA), were investigated. The results have shown that detection with Swedish blackpowder is the most suitable procedure as the percentage finger marks which were of adequate quality for further examination, was higher than with any other technique examined.     

Evaluation of alizarin and purpurin dyes for their ability to visualize latent fingermark on porous surfaces

Anthraquinones are a group of dye with many members and a wide range of industrial uses ranging from food, textiles to printing. Even though the reactions of anthraquinone dyes with amino acids are known, they have not yet been subjected to an examination regarding their ability in fingermark detection. In the presented study, the potential of alizarine and purpurin, natural anthraquinone dyes, as a fingermark reagent was examined in comparison with ninhydrin and lawsone. Alizarin and purpurin react with latent fingermark residue on copier paper and thermal paper to yield yellow-orange coloured impressions. The products formed also display photoluminescence properties when illuminated at 440 nm viewed through red filter. Both natural anthraquinone dyes exhibited some superior properties at the development of latent fingermarks on these surfaces compared to ninhydrin and lawsone.     

The effect of chlorine and hydrogen chloride on latent fingermark evidence

Exposure of forensic evidence to either hydrogen chloride or chlorine can result in acidification to such an extent that enhancement of fingermarks with ninhydrin or cyanoacrylate is inhibited. Under these circumstances, pretreatment of samples with volatile bases such as triethylamine or ethanolamine prior to using these enhancement techniques can lead to successful visualization of fingermarks. Alternatively, physical enhancement techniques such as powder dusting or small particle reagent can be used on acidified non-porous substrates, although the former technique is subject to increased background under such conditions.     

Latent fingermark development on a range of porous substrates using ninhydrin analogs--a comparison with ninhydrin and 1,8-diazofluoren

Three relatively new reagents for developing latent fingermarks on porous substrates, 1,2-indandione (IND), 5-methylthioninhydrin (5-MTN), and lawsone, are compared with the more widely used ninhydrin and 1,8-diazofluoren (DFO). Developed latent fingermark visualization on 10 different substrates comprising colored papers, cardboard, and cellophane rather than conventional printer and writing/notepad paper is assessed using latent fingermark deposits from 48 donors. Results show improved fluorescent fingermark visualization using IND compared with DFO on a range of colored cardboards and thick white paper, thus extending the range of substrates known to yield improved visualization with IND. Adding zinc chloride to IND failed to yield any further improvement in fluorescent fingermark visualization. 5-MTN (with and without zinc chloride posttreatment) showed no improvement in visualization compared with ninhydrin and DFO although visible fingermarks were developed. Lawsone produced fluorescent visible fingermarks only with white substrates, which were inferior to those produced with DFO.     

布料上掌纹的真空镀膜显现及DNA检验的研究

目的探究布料载体上潜掌纹经真空镀膜显现后,掌纹DNA提取相关影响因素与检出基因座数目的关系。方法分别进行出汗手与无汗手掌纹按压,放置不同时间;对提取的掌纹DNA进行定量检测;比较白色与黑色布料载体基因座数目检出情况。结果掌纹基因座数目检出随时间延长而递减,出汗手组基因座数目检出高于无汗手组,rfu值600时,基因座数目检出百分比90%,模板量阈值为0.013ng。同一提取方法白布基因座数目检出高于黑布,布料色素抑制PCR扩增,致使基因座检出数目减少。结论真空镀膜技术能够很好地应于掌纹DNA的检测。     

自动固相萃取法(SPE)提取常见安眠镇静药

目的为筛选检验血、尿中未知安眠镇静药和三环抗忧郁药建立一种简便、快速的自动固相萃取方法。方法采用美国Zymark公司的自动固相萃取仪和Waters公司的OasisHLB固相萃取柱,同步提取血、尿中的25种常见安眠镇静药(包括巴比妥类、苯二氮卓类、吩噻嗪类药物等)和三环抗忧郁药。结果尿中药物提取率大部分达到80%以上;血中药物提取率在75%以上。结论该方法具有提取过程自动化,操作简便快捷,提取回收率高、重现性好、提取物干净等特点,可用于实际案件中血、尿中未知安眠镇静药和三环抗忧郁药的提取检验。     

乌头类生物碱对心肌的毒性作用及分子毒理学研究进展

乌头属植物是被子植物亚门毛茛科中一类重要的有毒植物,也是我国最早有记载的药用有毒植物之一;其块根中多含有剧毒的二萜类双酯型生物碱?乌头碱,因个体差异、用法不当以及误服或投毒等原因而发生乌头中毒、甚至死亡的报道屡见不鲜。目前,对乌头碱的研究多局限在临床救治方面,缺乏对乌头碱毒性作用机制研究。本文参考国内外相关文献资料,对乌头碱的心肌细胞毒性作用机制进行了综述。     

The examination of glass particles using the interference objective. Part 2: A survey of flat and curved surfaces

The microscopical examination of original surfaces on casework sized glass particles using an interference objective and the interpretation of their interferograms is discussed. To reduce subjectivity, a numerical criterion was devised to assess the curvature of glass particles and this was then applied to a survey of window, container, tableware and vehicle glasses. Objects with curved surfaces produced particles that were distinctly curved while those from surfaces of both modern and old windows were clearly identifiable as flat. Apparently flat surfaces from tableware and containers almost always yielded specimens that were detectably curved. In addition, there was no evidence that a fracture surface would be confused with an original surface from a plain flat glass.In a ‘blind’ trial to assess the interferometric routines, three examiners correctly identified flat and curved surfaces on 15 particles derived from a selection of glass objects.     

PryJector: a device for in situ visualization of chemical and physical property distributions on surfaces using projection and hyperspectral imaging

Traditional forensic methods that highlight the spatial distribution of properties such as blood and fingerprints have two main disadvantages: they often apply chemicals that may influence further analyses, and they cannot easily be modified to search for new compounds/properties. A new instrument (called PryJector) avoids these problems by dynamically projecting back onto the surface under study spatially distributed information of compounds/properties (chemical images) obtained from multivariate analysis of hyperspectral images. Selectivity to target compounds/properties is ensured by multivariate modeling which makes the instrument much more flexible compared to traditional methods. The functionality of the PryJector is demonstrated in an application related to the detection of counterfeit pharmaceuticals where compounds otherwise indistinguishable to the human eye are made clearly visible by projection of false-colored chemical images. The PryJector is shown to be a noninvasive and very flexible instrument for highlighting spatial distributions of various compounds/properties.     

医事法学专业教学研究的现状与重大问题

为了培养兼具医学知识和法学知识的复合型医事法学人才,已有40余所院校设置医事法学专业。为了该朝阳专业的完善与发展,众多学者从多方面进行了大量研究,但该专业的教学却存在许多未解难题,毕业生的质量受到极大质疑。本文通过深入分析现有的研究,指出当前研究存在的三个重大问题：从感性出发研究医事法学专业的教育,缺乏数据支撑;在象牙塔内研究教育问题,缺乏与社会的联系;研究局限于学者、教师视角,缺乏毕业生对本专业回顾性的思考与批判。