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目的 探讨乳化炸药爆炸案件中导致爆炸残留物中铵根离子、硝酸根离子含量偏低的原因。方法 通过实际爆炸案例分析,实地了解乳化炸药制造工艺,采用离子色谱法检验爆炸案件及爆炸实验提取的残留物中铵根离子和硝酸根离子成分含量。通过与空白样本对比,分析导致乳化炸药爆炸残留物中铵根离子、硝酸根离子含量降低的原因。结果 经过生产工艺改进的乳化炸药爆炸后,其残留物中检出硝酸根和铵根离子的含量没有明显高于现场空白样本。结论 通过考察分析、对比检验,发现生产工艺改进是导致乳化炸药爆炸残留物中铵根离子和硝酸根离子含量偏低的原因。针对这一问题,本文提出了一些相应的解决方案。 相似文献
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1991年的《执法技术》报导了一种分析射击和爆炸残留物的新方法——胶束电动毛细管电泳(MECE)。该法通过测定微量射击和爆炸残留物中的有机组分,得到准确的鉴定结论。该方法中仪器花费少,样品制备简单。虽然MECE技术还处于早期实验阶段,但是国家标准和技术研究所(NIST)分析化学中心(CAC)从事这项工作的化学家WiHian Mac Crehan博士和David Northrop已有许多有价值的发现——能够鉴别发射药和炸 相似文献
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目的 阐述微流控芯片技术在法庭科学上的应用。方法 研究国内外已报道的微流控芯片快速、灵敏、高通量技术的有关资料。结果 提出在法医DNA检验、毒剂和毒物检测、麻醉剂或毒品检测、爆炸残留物检测等刑事技术上的应用前景。结论 从刑事侦查的角度看出该技术的巨大发展潜力 相似文献
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目的建立检验纵火案件现场燃烧残留物中助燃剂的一种方法。方法利用固相微萃取器吸附浓缩燃烧残留物中的挥发性气体,使用气相色谱仪对挥发性气体进行定性分析。结果固相微萃取与气相色谱仪联用能较好地对火场不同介质燃烧残留物中汽油、煤油、柴油等助燃剂进行种类认定。结论该方法简便易行。 相似文献
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微量物证技术相对其它刑事技术手段起步较晚,这是由于其科技含量高,涉及几乎所有工程学科和分析学科,人们对它的认识非常有限。我国微量物证技术起步于20世纪70年代,初期仅开展了油类、射击残留物和爆炸残留物的检验。1984年第一届全国微量物证检验学术交流会的召开,极大推动了微量物证技术的发展。80年代我国微量物证技术得到快速发展,微量物证技术人员不断增加,逐步引进了气相色谱仪、原子发射光谱仪、原子吸收光谱仪、紫外光谱仪、扫描电镜、付里叶显微红外光谱仪、液相色谱仪、示差扫描量热仪和气/质联用仪等大型分析仪器设备,微量物证… 相似文献
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1案件简介2005年浙江省衢州市某职教中心一教室内发生一起爆炸案件,造成讲台被完全炸毁、一女生耳朵被震听不清楚,头发被部分烧伤,一男生衣服被烧一个洞,学校的教学秩序受到了严重影响。现场勘查时从教室地面上、课桌椅上及讲台底部找出了17种400余件爆炸装置碎片。针对17种爆炸装置碎片进行列表,逐样分析其用途,再根据用途情况绘制出爆炸装置电路图,最后重建出遥控爆炸2.1对现场提取的17种爆炸装置碎片进行检验、调查见表12.2对现场提取的几种爆炸残留物进行分析2.2.1对电路板及钢丝的分析现场提取的一块电路板上面有“RX-3N4J7S”字样,… 相似文献
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Today the method commonly used for detecting gunshot residue is through the combined use of scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). In recent years, this same methodology began to find use in detecting and characterizing pyrotechnic reaction residue (PRR) particles whether produced by explosion or burning. This is accomplished by collecting particulate samples from a surface in the immediate area of the pyrotechnic reaction. Suspect PRR particles are identified by their morphology (typically 1 to 20 microm spheroidal particles) using an SEM; then they are analyzed for the elements they contain using X-ray EDS. This can help to identify the general type of pyrotechnic composition involved. 相似文献
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Pyrotechnic reaction residue particle (PRRP) production, sampling and analysis are all very similar to that for primer gunshot residue. In both cases, the preferred method of analysis uses scanning electron microscopy to locate suspect particles and then uses energy dispersive x-ray spectroscopy to characterize the particle's constituent chemical elements. There are relatively few times when standard micro-analytical chemistry performed on pyrotechnic residues may not provide sufficient information for forensic investigators. However, on those occasions, PRRP analysis provides a greatly improved ability to discriminate between materials of pyrotechnic origin and other unrelated substances also present. The greater specificity of PRRP analysis is the result of its analyzing a large number of individual micron-sized particles, rather than producing only a single integrated result such as produced using standard micro-analytical chemistry. For example, PRRP analyses are used to demonstrate its ability to successfully (1) discriminate between pyrotechnic residues and unrelated background contamination, (2) identify that two different pyrotechnic compositions had previously been exploded within the same device, and (3) establish the chronology of an incident involving two separate and closely occurring explosions. 相似文献
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In light of past research being targeted to find specific particles which may be similar to gunshot residue (GSR), this project was formulated to detect any possible particulate by random particle fallout onto substrates at firework displays and to assess the impact this may have on GSR evidence. Firework residue was collected at a display site, from amongst spectators as well as from the author's hair 90min after the display. SEM-EDX analysis has detected such particulate in all three scenarios, with the firework particle population at large providing a solid ground for discrimination from GSR. Wind dispersal was found to decrease the particle population and subsequently, the latter's discriminatory power. Some particles, if treated individually were found to be indistinguishable from GSR. Findings also include residues which may mimic strontium based GSR as well as GSR which may be mixed with that from previous firings. The continuous changes made to primer and propellant compositions by manufacturers also call for greater consideration when classifying particles as originating from pyrotechnic devices. Furthermore, authorities such as police forces should be made more aware about the incidence of such particle transfer in firework related periods. 相似文献
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Determination of synthesis route of 1-(3,4-methylenedioxyphenyl)-2-propanone (MDP-2-P) based on impurity profiles of MDMA 总被引:1,自引:0,他引:1
Swist M Wilamowski J Zuba D Kochana J Parczewski A 《Forensic science international》2005,149(2-3):181-192
In our study 1-(3,4-methylenedioxyphenyl)-2-propanone (MDP-2-P or PMK) was prepared by two different routes, i.e. by oxidizing isosafrole in an acid medium and by 1-(3,4-methylenedioxyphenyl)-2-nitropropene reduction. The final product-MDP-2-P was subjected to GC/MS analysis. The intermediates and reaction by-products were identified and the 'route specific' impurities were established. The following impurities are the markers of the greatest importance: 1-(3,4-methylenedioxyphenyl)-1-propanone (compound 10, Table 2), 1-methoxy-1-(3,4-methylenedioxyphenyl)-2-propanone (compound 11, Table 2) and 2,2,4-trimethyl-5-(3,4-methylenedioxyphenyl)-[1,3]dioxolane (compound 13, Table 2) (the 'oxidising isosafrole route') and N-cyclohexylacetamide (compound 3, Table 1), 3-methyl-6,7-methylenedioxyisoquinoline-1,4-dione (compound 15, Table 1) (the 'MDP-2-nitropropene reduction route'). Subsequently, MDMA was prepared by reductive amination of MDP-2-P using NaBH4 as reducing agent (so-called 'cool method'). Impurities were extracted with n-heptane under alkaline conditions. The impurity profiles were obtained by means of GC/MS, some reaction by-products were identified by means of the EI mass spectra including low energy EI mass spectra and 'route specific' impurities were established. 4-Methyl-5-(3,4-methylenedioxyphenyl)-[1,3]dioxolan-2-one (compound 22, Table 2), N-methyl-2-methoxy-1-methyl-2-(3,4-methylenedioxyphenyl)-ethaneamine (compound 18, Table 2), 3-methyl-6,7-methylenedioxyisoquinoline-1,4-dione (compound 15, Table 1) and N-cyclohexyloacetamide (compound 3, Table 1) were found to be the synthesis markers of greatest importance. 相似文献
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This paper describes the structural elucidation of a compound produced during the synthesis of 3,4-methylenedioxymethylamphetamine (MDMA) via the reductive amination of 3,4-methylenedioxyphenyl-2-propanone (3,4-MDP-2-P) with methylamine and sodium cyanoborohydride. The compound was isolated from MDMA by column chromatography, proton and carbon nuclear magnetic resonance spectroscopy, LC/mass spectrometry, and total synthesis were used to identify the compound as N-cyanomethyl-N-methyl-1-(3',4'-methylenedioxyphenyl)-2-propylamine. This compound has been identified as a potential synthetic route marker for the reductive amination of 3,4-MDP-2-P with methylamine and sodium cyanoborohydride and as such it should prove valuable to forensic scientists engaged in profiling illicit drugs. Profiling MDMA can provide useful information to law enforcement agencies relating to synthetic route, precursor chemicals and reagents employed and may be used for comparative analyses of different drug seizures. This paper also describes the structural elucidation of the analogous methylamphetamine synthetic route marker compound, N-cyanomethyl-N-methyl-1-phenyl-2-propylamine, produced during the reductive amination of phenyl-2-propanone using methylamine and sodium cyanoborohydride. 相似文献
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N,N-diethyl-m-toluamide (DEET) levels in postmortem specimens of stomach and contents, blood, liver, and urine are reported following ingestion of the compound. DEET was analyzed by gas chromatography with an OV-101 column and a nitrogen phosphorus detector. The presence of the compound in the four postmortem specimens was confirmed by mass spectrometry. 相似文献
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The cocaine body-packer syndrome: evaluation of a method of contrast study of the bowel 总被引:1,自引:0,他引:1
B Marc F J Baud M J Aelion R Gherardi O Diamant-Berger M Blery C Bismuth 《Journal of forensic sciences》1990,35(2):345-355
The questionable reliability of the conventional procedures for detection of ingested drug packages triggered us to evaluate the accuracy of a method of contrast study of the bowel in 23 nonsurgically managed cocaine body-packers. A single dose (60 mL) of a water-soluble contrast compound (amidotrizoate + meglumine) was given orally after initial clinical examination and drug detection in urine. Thereafter, roentgenograms were performed daily after spontaneous passage until obtaining two packet-free stools and negative views. Roentgenograms showed packages when performed at least 3 h after the ingestion of the contrast compound. Sensitivity and specificity of the method with respect to the detection of residual packets in the body, assessed by subsequent examination of stools, was good and did not diminish as the number of packages decreased during the time spent in ward. No side-effects were observed. We conclude that oral administration of a water-soluble contrast compound is an easily performed, efficient, and safe method for the nonsurgical management of cocaine body-packers. 相似文献
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An unknown, viscous, opaque, white liquid with a strong, unpleasant odor was submitted with a request for identification. It was analyzed using infrared (IR) spectroscopy, gas chromatography–mass spectrometry, and X‐ray fluorescence spectroscopy. It was found to contain glycerin as well as another compound. IR and mass spectral data were readily obtained for this second component, but it was not easily identified as common instrument libraries had no matching spectra. After an extensive literature search, the unknown compound was identified as spiromesifen, a recently introduced pesticide. The IR spectrum and electron impact mass spectrum of spiromesifen are presented here as these are not available in the published literature. This case report also provides useful approaches for searching for and identifying an unknown compound when it is not found in a laboratory's spectral libraries. 相似文献
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The estimation of time since the latest discharge of pistols and revolvers has been achieved by the Solid Phase Microextraction (SPME) sampling technique and the GC/TEA analytical system. The TEA2 compound, which in our previous work (1) was observed in barrels of shotguns and rifles as well as inside spent cartridges, was also detected in pistols and revolvers. The amount of this compound was very low in short-barreled small arms and its escape from the barrel could generally be measured for only a few days or up to two weeks after the latest discharge. To improve the detection of TEA2 compound, the SPME sampling time was prolonged and fibers coated by Carboxen/polydimethylsiloxane were used. The decrease of the TEA2 peak with time after shooting from pistols is nonexponential but the curve-fitting procedure proposed for the estimation of time since discharge of shotguns and rifles is difficult to apply as the decay is very rapid. Therefore, the detection of TEA2 compounds in small arms should be interpreted that the firearm had been used very recently. The amount of volatile decomposition products of smokeless powder increased significantly with the length of the barrel when firearms of the same caliber, but with different barrel lengths were investigated. 相似文献