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11.
苯丙胺类毒品三氟乙酰化气一质联用分析   总被引:2,自引:1,他引:1  
目的 考查了N甲基双三氟乙酰胺 (MBTFA)衍生化试剂对苯丙胺类毒品的衍生化效果与衍生化条件 ,建立该类毒品三氟乙酰化后的定性定量分析条件。方法 用三氟乙酰化气一质联用分析方法。结果 获得了衍生化产物经气质联用分析后的总离子流色谱图、质谱图及质谱断裂规律 ,以及各种定量参数。结论 经三氟乙酰化后分离效果得到改善 ,且衍生化完全 ,可用于该类毒品的定量分析。  相似文献   
12.
目的建立葡萄叶中2甲4氯、2,4-滴和2,4-滴丙酸3种苯氧羧酸类除草剂的二氯丙基酯化-电子俘获检测气相色谱分析法。方法样品捣碎、添加内标2,4-二氯苯乙酸、酸化、用乙醚提取,提取液用液液分配法净化,净化后挥干有机溶液,用硫酸和1,3-二氯丙-2-醇进行酯化,生成的酯进行气相色谱分析。结果葡萄叶中2甲4氯、2,4-滴和2,4-滴丙酸的检测限分别为20ng/g、20ng/g和30ng/g,葡萄叶中除草剂浓度100~1000 ng/g成线性关系,空白葡萄叶中添加2甲4氯、2,4-滴和2,4-滴丙酸200ng/g的平均回收率分别为98.8%、101.3%和103.1%,回收率的变异系数分别为11.4%、11.0%和9.3%。结论本文方法检测被毒害的葡萄叶中3种除草剂是灵敏和准确的。  相似文献   
13.
Abstract:  The illicit manufacture of heroin results in the formation of trace level acidic and neutral impurities. These impurities are detectable in illicit heroin and provide valuable information about the manufacturing process used. The isolation, derivatization, and semiquantitative analysis of neutral and acidic heroin manufacturing impurities by programmed temperature vaporizing injector-gas chromatography-mass spectrometry (PTV-GC-MS) is described. Trace acidic and neutral heroin impurities were isolated from basic fractions using liquid–liquid extraction. Extracted impurities were treated with N -Methyl- N -trimethylsilyltrifluoroacetamide followed by PTV-GC-MS analyses. Semiquantitative data were obtained using full scan mass spectrometry utilizing unique ions or ion combinations for 36 trace impurities found in crude and/or highly refined heroin samples. Minimum detection limits for acidic and neutral impurities were estimated to be at the 10−7 level relative to total morphine. Over 500 authentic heroin samples from South America, Mexico, Southwest Asia, and Southeast Asia were analyzed. Classification of illicit heroin based on the presence or absence and relative amounts of acidic and neutral impurities is presented.  相似文献   
14.
Human hair is frequently encountered as forensic evidence and can contribute valuable information to investigators. Conventional forensic hair analyses include microscopic hair comparison (MHC) and DNA analysis. However, MHC is not supported by statistics and DNA analysis cannot always be performed. Recent studies have demonstrated that evaluation of differences in the hair proteins may offer an alternate method to these analyses. In this study, an evaluation of the amino acids present in hair was investigated as an approach to differentiate morphologically indistinguishable hair samples from two demographically similar individuals. Proteins in the hair were digested using hydrochloric acid, and the resulting amino acids were derivatized with N,O-Bis(trimethylsilyl)trifluoroacetamide (BSTFA) for analysis using gas chromatography-mass spectrometry (GC-MS). Eight derivatized amino acids were detected and quantified relative to an internal standard, L-norvaline, and used to construct twenty-eight amino acid ratios. Hair samples were collected from four areas of the head on various days over the course of one month, and no significant differences in amino acid ratios (p-value > 0.05) were observed among the areas of the head, and the ratios were consistent over the time period of this study. Additionally, fifteen of these amino acid ratios were found to be significantly different between the two individuals when compared using a two-sample t-test (p-value ≤ 0.05). These data indicate that amino acid analysis was able to differentiate two morphologically similar hair samples from different individuals and demonstrates the applicability of this method to distinguish similar hair samples when DNA analysis cannot be performed.  相似文献   
15.
目的用五氟丙酰衍生化-气相色谱/质谱联用法分析尿液中硝西泮的主要代谢物7-氨基硝西泮。方法尿液经乙醚萃取后,用五氟丙酰酸酐(PFPA)进行衍生化,得到7-氨基硝西泮衍生化物的总离子流色谱图和质谱图。结果根据7-氨基硝西泮衍生化物色谱的保留时间和质谱中主要特征离子的质荷比进行定性分析;用7-氨基氟硝西泮做内标,以7-氨基硝西泮和内标衍生化物定量离子的色谱峰面积比与浓度的关系进行定量分析。结论用五氟丙酰衍生化-GC/MS分析尿液中硝西泮的主要代谢物7-氨基硝西泮的方法定性、定量灵敏准确,测定结果可应用于司法鉴定。  相似文献   
16.
A sensitive and reliable method for extraction and quantification of benzoylecgonine (BZE) and cocaine (COC) in urine is presented. Propyl‐chloroformate was used as derivatizing agent, and it was directly added to the urine sample: the propyl derivative and COC were then recovered by liquid–liquid extraction procedure. Gas chromatography–mass spectrometry was used to detect the analytes in selected ion monitoring mode. The method proved to be precise for BZE and COC both in term of intraday and interday analysis, with a coefficient of variation (CV) <6%. Limits of detection (LOD) were 2.7 ng/mL for BZE and 1.4 ng/mL for COC. The calibration curve showed a linear relationship for BZE and COC (r2 >0.999 and >0.997, respectively) within the range investigated. The method, applied to thirty authentic samples, showed to be very simple, fast, and reliable, so it can be easily applied in routine analysis for the quantification of BZE and COC in urine samples.  相似文献   
17.
目的建立稻田水中莠去津及其代谢物去乙基莠去津(DEA)、去异丙基莠去津(DIA)和双去烃基莠去津(DDA)的灵敏的气质联用分析方法。方法稻田水样品用GDX501大孔树脂进行固相萃取,萃取物用N,O-双三甲硅烷基乙酰胺(BSA)进行三甲硅烷基衍生化,衍生物用选择离子监测的气质联用法分析。结果稻田水中4种分析物的检出限和测量限都不高于2ng/mL。结论该方法可用于刑事案件中莠去津毁坏稻田案件的检验。  相似文献   
18.
目的建立一种检验生物检材中无机氰化物的GCMS/MS方法。方法首先将生物检材中的无机氰化物在酸性条件下蒸馏出,用碱性溶液吸收后,氰离子在相转移催化剂作用下被五氟苄基溴(PFB-Br)衍生化,最后用GC-MS/MS法分析衍生化产物。结果衍生化产物PFB-CN的MS/MS质谱图特征性强,定性准确;在20-1500ng/g浓度范围内呈良好的线性关系(r=0.998),最低检测限为5ng/g,回收率为82.3%-98.6%。结论本方法简单实用,灵敏度高,准确可靠,适用于生物检材中无机氰化物的检验。  相似文献   
19.
Zopiclone (ZOP) is a hypnotic drug prescribed to treat insomnia. Due to the chiral nature of ZOP, the psychologically active S-form and inactive R-form need to be determined enantiomerically in a forensic drug analysis. In the present study, a supercritical fluid chromatography (SFC) method was designed with a faster analysis ability than that of previously reported techniques. The SFC–tandem mass spectrometry (SFC–MS/MS) method was optimized using a column with a chiral polysaccharide stationary phase (Trefoil CEL2). ZOP was extracted from pooled human serum using solid-phase extraction (Oasis HLB) and analyzed. The developed SFC–MS/MS method achieved the baseline separation of S-ZOP and R-ZOP within 2 min. The fit-for-purpose method validation indicated that the optimized solid-phase extraction achieved near complete recovery and approximately 70% of the matrix effect. Both the retention time and peak area showed sufficient precision. The lower and upper limits of quantification (LOQ) were 5.7 × 10−2 ng/mL and 25 ng/mL for R-ZOP, and 5.2 × 10−2 ng/mL and 25 ng/mL for S-ZOP. The calibration line was linear in the range from lower LOQ to upper LOQ. The stability test indicated that ZOP in serum stored in a refrigerator (4°C) degraded and about 55% remained in 31 days. The quick analysis of the SFC–MS/MS method makes it a valid option for the enantiomeric analysis of ZOP.  相似文献   
20.
分析裂解衍生化技术及其在刑事技术中的应用   总被引:3,自引:2,他引:1  
介绍了近年来分析裂解衍生化反应技术,如加氢还原法;基质修饰剂法;同时裂解甲基化法;同时热液分解法.并就该技术的现状、原理、进展及其在刑事技术中的应用进行了综述.  相似文献   
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