离子交换柱法萃取血样中4种巴比妥类药物

目的建立血样中4种常见巴比妥类药物的固相萃取方法。方法采用Oasis MAX固相萃取柱对样品进行预处理,以2%氨水淋洗2,%甲酸-甲醇洗脱,GC/NPD定量检验,GC/MS定性检验。结果血样中4种常见巴比妥类药物平均萃取回收率达80%以上,以信噪比10/1计,最小定量限为1～2μg/mL,以信噪比3/1计,检出限为0.5～1μg/mL,在1～50μg/mL范围内,线性相关系数均在0.99以上。结论本文固相萃取方法检出限低,回收率高,选择性强,可应用于血样中4种常见巴比妥类药物的检测。     

用基质分散固相萃取法用于人血中有机磷农药检测

目的建立基质分散固相萃取方法用于检测人体血液中有机磷农药。方法利用C18、PSA和石墨化碳为吸附剂,采用基质分散固相萃取与GC/MS法相结合检测人体血液中甲胺磷、敌敌畏、甲拌磷、乐果、叔丁硫磷、甲基对硫磷、马拉硫磷等8种有机磷农药。结果 8种有机磷农药分离效果良好,回收率在71.46%～96.09%之间,检出限在0.26～4.52ng之间。结论基质分散固相萃取方法提取血中有机磷农药操作简单、快速准确。     

Development of a quantitative LC-MS/MS method for the analysis of common propellant powder stabilizers in gunshot residue

In traditional scanning electron microscopy/energy dispersive X-ray analysis of gunshot residue (GSR), one has to cope more and more frequently with limitations of this technique due to the use of lead-free ammunition or ammunition lacking heavy metals. New methods for the analysis of the organic components of common propellant powder stabilizers were developed based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). A multiple reactions monitoring scanning method was created for the screening of akardite II, ethylcentralite, diphenylamine, methylcentralite, N-nitrosodiphenylamine, 2-nitrodiphenylamine, and 4-nitrodiphenylamine, present in standards mixtures. Five out of seven of these target compounds can be selectively identified and distinguished from the two others with a high accuracy. Samples from the hands of a shooter were collected by swabbing and underwent solid phase extraction prior to analysis. Detection limits ranging from 5 to 115 mug injected were achieved. Results from several firing trials show that the LC-MS/MS method is suitable for the detection of stabilizers in samples collected following the firing of 9 mm Para ammunitions.     

Fragrance transfer between fabrics for forensic reconstruction applications

Sexual assault is a serious crime that often has low conviction rates. Recent literature has demonstrated that there is potential for fragrances to be valuable in forensic reconstructions where there has been contact between individuals. However, developing appropriate evidence bases for understanding the nature of fragrance transfer in these contexts is needed. This article presents three experiments that address the transfer process of fragrances that have been transferred from a primary piece of fabric onto a secondary piece of fabric, in a manner that could occur during an assault. The three variables studied were the ageing time of the fragrances on the first fabric prior to transfer, the contact time between the two fabrics, and lastly the fabric type (of the primary material and the recipient material). The transfer was evaluated using a validated solid phase micro-extraction gas chromatography–mass spectrometry (SPME GC–MS) method. The findings demonstrated that all three variables had an impact on the transfer of fragrances between clothing fabrics. Generally, lower volatility compounds were transferred and recovered in larger amounts than higher volatility compounds. All fragrance compounds were successfully recovered from a secondary piece of fabric even when the contact time was as short as 10 s, and even when the perfume was aged on the primary fabric for as long as 48 h. The nature of the fragrance transfer also depended on the fabric type, so that a clear discrimination was observed between the fragrance transfer that occurred onto a natural fabric (cotton) and onto a synthetic fabric (polyester).     

中美经济周期波动特征比较研究

本文参照基德兰德(Kydland)、普雷斯科特(Prescott)的研究方法,通过比较中美经济周期波动的特征和周期性,发现中美经济波动尤其是名义变量的波动存在比较明显的差异。从理论上讲,这种差异的存在表明要建立适合我国的经济模型,必须立足于我国的经济特征事实,并有限地参考他国尤其是美国的经济特征事实;从现实层面来看,我国应该大力完善金融货币制度,减少名义变量对实际经济的影响,以实现经济的稳定增长。     

关于新民主主义社会与社会主义初级阶段的异同

认清社会主义初级阶段与新民主主义社会异同的关键是认清社会主义初级阶段的性质。社会主义初级阶段与新民主主义社会有很多相同之处，同时也有不同之处。     

乌头碱在家兔体内的代谢动力学初步研究

本文应用甲醇-0.05mol/L碳酸铵水溶液-二氯甲烷(90:10:2)作流动相,在YWGC_(18)H_(37)反相键合相色谱柱上分离乌头碱和内标,用紫外分光检测器在235nm外定量,改进了动物组织内痕量乌头碱的HPLC检测法。运用该法检测家兔静脉注射乌头碱后的血毒物浓度,初步研究了乌头碱在家兔体内的代谢动力学过程,表明其体内过程符合开放二室模型,T_(1/2α)=1.4682min,T_(1/2β)=34.1379min。体内乌头碱可以原形由尿和胆汁中排出,但以前6h尿排泄为主。     

静松灵的检验

本实验建立了用固相萃取(SPE)、薄层色谱和气—质联用法(GC-MS)分析血、尿、肝中静松灵的方法,在1g尿、血、肝中添加0.01mg药物、回收率分别为96.1%、90%、67%.该方法简单快速准确,经动物实验及案件鉴定验证,效果较好.     

埋葬4年的开棺腐败尸体中安定、氯丙嗪等6种安眠药物的检验

本文介绍用SPE提取、GC/MS检验埋葬4年的开棺腐败检材中安定、氯丙嗪等6种安眠药物的新方法.哦     

The Stability of Collected Human Scent Under Various Environmental Conditions*,†

Abstract: Human scent evidence collected from objects at a crime scene is used for scent discrimination with specially trained canines. Storage of the scent evidence is usually required yet no optimized storage protocol has been determined. Storage containers including glass, polyethylene, and aluminized pouches were evaluated to determine the optimal medium for storing human scent evidence of which glass was determined to be the optimal storage matrix. Hand odor samples were collected on three different sorbent materials, sealed in glass vials and subjected to different storage environments including room temperature, ?80°C conditions, dark storage, and UVA/UVB light exposure over a 7‐week period. Volatile organic compounds (VOCs) in the headspace of the samples were extracted and identified using solid‐phase micro‐extraction–gas chromatography/mass spectrometry (SPME–GC/MS). Three‐dimensional covariance mapping showed that glass containers subjected to minimal UVA/UVB light exposure provide the most stable environment for stored human scent samples.