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61.
液态爆炸物具有制造简易、不易识别、威力巨大、易于引爆等特点,这些特点增加了液态爆炸物安全检查的难度。液态爆炸物的安全检查分为探测、防护和处置三个环节。针对探测环节,文章综述了国内外主要使用的液态爆炸物探测技术及其特点,介绍了有代表性的技术产品,探讨了液态爆炸物探测技术的发展趋势,最后,对我国液态爆炸物安全检查行业的技术发展提出了几点建议。  相似文献   
62.
A method using liquid chromatography–tandem mass spectrometry (LC–MS/MS) to simultaneously quantify amphetamines, opiates, ketamine, cocaine, and metabolites in human hair is described. Hair samples (50 mg) were extracted with methanol utilizing cryogenic grinding. Calibration curves for all the analytes were established in the concentration range 0.05–10 ng/mg. The recoveries were above 72%, except for AMP at the limit of quantification (LOQ), which was 48%. The accuracies were within ±20% at the LOQ (0.05 ng/mg) and between −11% and 13.3% at 0.3 and 9.5 ng/mg, respectively. The intraday and interday precisions were within 19.6% and 19.8%, respectively. A proficiency test was applied to the validated method with z-scores within ±2, demonstrating the accuracy of the method for the determination of drugs of abuse in the hair of individuals suspected of abusing drugs. The hair concentration ranges, means, and medians are summarized for abused drugs in 158 authentic cases.  相似文献   
63.
The purpose of this research is to determine if latent fingerprints deposited on the exterior glass surfaces of vehicles, then covered in debris, can be recovered. Past research used liquid latex to lift soot to recover trace evidence. Recently, liquid latex has been used to recover latent fingerprints along the bottom of vehicles. In this study, a total of 216 latent fingerprints were deposited on the exterior windows of three vehicles. Three control and three experimental latent fingerprints were placed on each side window. The vehicles collected debris for either 2, 3, or 4 weeks. After debris collection, liquid latex was applied to the experimental sections. The underlying fingerprints were developed with white granular powder. Control fingerprints were developed directly with white granular powder. A chi-square test revealed a significant difference in fingerprint recovery between the control and liquid latex method (X2 = 9.026, d.f. = 1, p = 0.003). An odds ratio determined that the control method increases the probability of latent fingerprint recovery by 2.68. Fisher's exact test indicated that there is no statistically significant difference between the detail of the recovered control and experimental fingerprints (p = 0.065). This study demonstrates that recovery of fingerprints is possible using the liquid latex method; however, the control method recovers more fingerprints on the glass exterior of vehicles. If latent fingerprints are thought to be present on the exterior glass surfaces of vehicles, the control method should be used to improve vehicle processing by investigators.  相似文献   
64.
In Algeria, large quantities of hashish are seized every year. This study aimed to investigate the total content of major cannabinoids in the illicit seized hashish in Algeria over an 8-year period (2011–2018) in order to establish the chemical profile of North African hashish. A total of 3265 hashish samples were analyzed using a validated high-performance liquid chromatography–diode array detection (HPLC-DAD) method, allowing the simultaneous quantification of both the acidic and the neutral forms of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN). The results revealed a slight upward trend in the mean THC content, from 7.0% in 2011 to 9.4% in 2018, with an overall mean value of 8.4%. The overall means of CBD and CBN content were 3.5% and 0.8%, respectively. The number of high-potency hashish samples gradually increased to reach 6% in 2018. Two distinct hashish chemotypes were identified: the highly populated chemotype II, corresponding to the traditional medium-potency hashish ([THC + CBN]/CBD ~ 2.16), and chemotype I, containing hashish samples of relatively high THC levels and low levels of CBD (ratio ~ 4.90). Both chemotypes I and II were characterized in the ternary plot, and the proportions (THC:CBD:CBN) were about 85%:13%:2% and 60%:35%:5%, respectively.  相似文献   
65.
目的 采用超高效液相色谱法(ultra performance liquid chromatography,UPLC)建立绿萼梅药材的指纹图谱,为有效控制绿萼梅药材的质量奠定基础。方法 采用CORTECS C18色谱柱(2.1 mm×100 mm,1.6 μm),以乙腈(A)-0.1%甲酸水(B)溶液为流动相进行梯度洗脱,进样量为1 μL,流速为0.3 mL/min,检测波长260 nm。结果 通过相似度分析确定19个色谱峰构成绿萼梅药材指纹图谱的特征峰。结论 采用UPLC方法建立的指纹图谱具有精密度、稳定性、重复性良好的特点,可为绿萼梅化学成分的进一步提取分离和药效物质基础的研究提供科学依据。  相似文献   
66.
A case of suspected acute and lethal intoxication caused by colchicine has been reported. The woman was hospitalized after her suspicion of suicidal poisoning by a rare autumn crocus (Colchicum autumnale). Suspected colchicine poisoning was confirmed using a novel UHPLC method with a modern reversed‐phase stationary phase with a sub 2‐micron superficial porous particle size combined with a QTOF mass spectrometer. Sample preparation procedure included the addition of propiverine as internal standard, protein precipitation using methanol and solid phase extraction. High‐resolution MS only and targeted MS/MS modes are reported for the qualitative analysis and screening of other potential drugs of abuse in blood samples. All Ion MS mode was used for quantitative determination of colchicine afterward. The concentration of colchicine in the blood sample was approximately 41 ng/mL, and more than 200 μg/mL of the plant extract used for the suicide.  相似文献   
67.
Fentanyl deaths have increased with availability of transdermal patches. Interpretation of postmortem fentanyl levels may be complicated by postmortem redistribution and absorption of fentanyl from a patch. We applied an unused 100‐μg/h fentanyl patch onto the lower abdomen of a decedent with no premortem fentanyl exposure. Ocular fluid, blood, and urine were collected prior to placement, and the decedent was refrigerated for 23 h. Prior to the autopsy, urine, subcutaneous tissue under the patch, and samples from the same anatomic sites were obtained. We observed no fentanyl in any postpatch placement samples (LOD: 0.1 ng/mL for blood and vitreous fluid, 1.0 ng/mL urine, 2.0 ng/g for tissues). Although we observed no postmortem absorption of fentanyl, this was only a single case; therefore, we recommend that patches be removed after receipt of a cadaver before initiation of an autopsy, with the location of removed patch documented.  相似文献   
68.
Objective To develop a liquid chromatography-tandem mass spectrometry(LC-MS/MS) screening method for 45 poisonous alkaloids in blood. Methods Identification was based on the compound’s retention time and two precursor-to-production transitions. The method involved a liquid-liquid extraction(LLE) followed by LC-MS/MS with multiple-reaction monitoring(MRM). When 1 m L of blood was extracted with diethyl ether at p H=9.2 with SKF525 Aas the internal standard, the target compounds were analyzed with LC-MS/MS in the positive ionization mode. Results The target alkaloids had good linearity(r>0.995 1), both the intra-day precision and inter-day precision being less than 14.77%. The limits of detection ranged from 0.05 to 25 ng/m L in blood. Conclusion The method is selective and sensitive in detecting poisonous alkaloids with a total running time of 12 minutes; therefore it was successfully applied to some actual cases of suspected alkaloids poisoning.  相似文献   
69.
犯罪嫌疑人遗留在各种光滑平面上的新鲜或陈旧性汗液指印,由于潜在指印与背景之间的反射亮度差很小,加之背景颜色的干扰,一般光照条件下拍摄相当困难。运用定向反射照相法,能加强纹线与背景的亮度差异,消除背景颜色的干扰,取得较好的拍摄效果。  相似文献   
70.
目的研究采用中空纤维膜液相微萃取(hollowfiber liquid phase microextraction,HF-LPME)法提取水和生物体液中的哌替啶,氯胺酮,曲马多。方法样品调节至pH11.5和盐饱和,磁力搅拌器转速为600转/min,内标为盐酸萘福泮,取4μl甲苯,注入到聚偏氟乙烯中空纤维膜中,萃取20min,抽回1μl甲苯进入GC中进行分析。结果血浆、尿、水相关系数R2:哌替啶分别为0.9935、0.9981、0.9997,氯胺酮分别为0.9906、0.9913、0.9927,曲马多分别为0.9741、0.9913、0.9970;检测限:水、尿中哌替啶、氯胺酮、曲马多均为0.01μg/ml,血浆中哌替啶、氯胺酮、曲马多均为0.05μg/ml;血浆、尿、水日内RSD:哌替啶分别为13.0%、7.3%、4.6%,氯胺酮分别为15.1%、13.6%、1.4%,曲马多分别为3.7%、4.3%、9.0%;血浆、尿、水日间RSD:哌替啶分别为15.1%、13.5%、12.2%,氯胺酮分别为12.3%、5.3%、6.0%,曲马多分别为7.1%、15.5%、11.9%;血浆、尿、水相对回收率:哌替啶分别为109.80%、93.49%、97.57%,氯胺酮分别为91.09%、101.80%、100.40%,曲马多分别为106.40%、92.94%、113.32%。结论中空纤维膜液相微萃取用于水和生物体液中的哌替啶,氯胺酮,曲马多的分析,所需有机溶剂少,避免残留和交叉污染,集萃取,富集,进样于一步完成,简单,高效,实用。  相似文献   
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