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291.
The susceptibility for recreational shooters to transfer gunshot residue (GSR) to both the interior and exterior of a vehicle is investigated. A comprehensive sampling protocol was used to assess the most likely areas of GSR transfer from recreational shooter contact, such as the steering wheel and the area, the firearms were stored (the trunk). Up to 315 characteristic GSR, particles were found in several locations throughout the interior of a vehicle. As many as 876 characteristic particles were found throughout a single vehicle. The data indicate that vehicles frequently occupied by firearms users are a potential source for inadvertent transfer of GSR to persons unrelated to firearm activity. In criminal cases where vehicles have been used, such transfer processes for GSR need to be considered within the context of any case interpretation. The implications for subsequent contamination and transfer processes from such vehicles require further investigation.  相似文献   
292.
目的探索饮酒后人体内血醇浓度(BAC)变化及其影响因素,建立BAC代谢的数学模型。方法采用顶空气相色谱氢火焰离子化检测器和内标曲线法测量酒后人体内的BAC,利用SPSS20.0和R软件对数据进行相关性分析并建立数学模型。结果女性的平均BAC消除速率为9.54mg/100m L/h,男性的平均BAC消除速率为12.19mg/100m L/h,女性消除速率小于男性,并且BAC消除速率与性别中等相关,与体重强相关,与年龄无关。通过构建混合效应模型可以准确的预测BAC,该模型的平均绝对误差(MAE)为1.60mg/100m L,其次利用决策树分析数据,其MAE为9.99mg/100m L。结论饮酒后人体内BAC消除速率与性别、体重有关,通过时间、饮酒量、性别、体重建立混合效应模型可以准确推断BAC。  相似文献   
293.
文章利用傅立叶红外光谱(ATR)法对收集到的纺织纤维样品进行种类上的区分,包括同种颜色(红色)不同品牌不同厂家的毛绒纤维样品,同一品牌相近颜色的纺织纤维样品,同种颜色(红色)不同品牌不同厂家的羊绒、腈纶纤维样品。根据红外谱图、数据分析,将纺织纤维样品分为3组,每组均为2类。其实验结果表明,红外光谱(ATR)法对于分析纺织纤维样品,分析速度快、样品需求量小,而且无损、不消耗检材,通过重复性实验,证实了其实验结果准确可靠。  相似文献   
294.
Lip balm may be encountered as physical evidence in cases involving sexual assaults, homicides, and kidnappings. Lip balm can be used as corroborative evidence by providing a potential link between the victim, accused, and the crime scene. For lip balms to be used as evidence, it is important to understand the diversity and their aging process under different conditions. Therefore, in this study, ATR-FTIR spectroscopy in conjunction with chemometric tools such as principal component analysis (PCA) and linear discriminant analysis (LDA) has been used for the objective identification and differentiation of 20 brands of lip balms. Moreover, lip balms on different substrates and wearing effects over time were also investigated. The results show that the PCA-LDA training accuracy was 92.5%, whereas the validation accuracy comes out to be 83.33%. A blind study using pristine samples was also performed which resulted in 80% PCA-LDA accuracy. PCA-LDA prediction of samples on various substrates showed a higher chemometric prediction accuracy for nonporous substrates (glass, plastic, and steel), than for porous substrates (cotton cloth, cotton swab stick, dry tissue paper, and white paper) for samples kept in room temperature and under sunlight for 15 days. The substrate study showed that the samples from various substrates could effectively generate respective spectra which can help in brand-level identification even after several days. The present method demonstrates a potential for lip balm samples to be used in forensic casework applications.  相似文献   
295.
目的对子弹物证进行成分分析可为涉枪案件的侦查提供科学依据。本实验旨在通过研究子弹弹头及弹壳的元素组成快速区分不同子弹,为推断子弹来源提供关键信息。方法收集不同厂家在1958-2019年不同批次生产的多种型号的子弹样品53份,应用扫描电镜能谱法(SEM/EDX)对样品的弹头内芯、弹头披甲和弹壳金属成分进行研究。结果结果显示多数子弹弹头内芯由纯铅构成,部分批次较晚的弹头为铅锑合金,另有两枚批次较早子弹为铁弹头;除六枚5.6mm运动步枪弹的弹头披甲以及四枚791厂样品的弹壳无明显特征外,其余子弹的弹头披甲和弹壳均为三类铜锌合金中的一种:含铜量83.7%~84.7%、87.6%~90.6%以及67.0%~69.8%的铜锌合金。同型号同厂家子弹所使用弹头披甲及弹壳材料的特征相似,同型号不同厂家、同厂家不同型号的子弹弹头披甲和弹壳材料则具有一定差异。近六十年来121厂样品子弹弹头披甲均为含铜量87.6%~90.6%的铜锌合金,弹壳材料为含铜量67.0%~69.8%的铜锌合金,其为该厂固定使用的铜锌合金原材料的可能性较高。791厂样品中有四种型号的子弹弹壳均为含锰量0.7%~0.9%的铁锰合金,这种合金在其他厂家并未出现,其为791厂弹壳特征原材料的可能性较高。结论掌握子弹弹头及弹壳的元素组成特征可以对不同子弹进行有效识别。  相似文献   
296.
颜廷平 《桂海论丛》2010,26(5):82-86
中国共产党的社会整合模式随着社会经济、政治、文化等的发展而不断创新:在新民主主义革命局部执政时期逐步构建了政党主导型社会整合模式;在社会主义改造时期逐步构建了政府主导型社会整合模式;在改革开放时期积极构建多元契约性社会整合模式。细致梳理党的社会整合模式创新脉络,归纳其时代启示,对构建社会主义和谐社会有着积极的促进作用。  相似文献   
297.
死后大鼠脾脏组织FTIR测量结果的法医学分析   总被引:1,自引:0,他引:1  
目的应用傅里叶变换红外(FTIR)光谱技术分析大鼠死后脾脏组织随死亡时间增加的化学变化过程,为死亡时间推断研究提供新的途径与研究数据。方法大鼠断颈处死后,在30℃、20℃及4℃环境中,不同死亡时间点提取大鼠脾脏组织,并运用FTIR光谱仪测定不同化学基团随死亡时间的变化。结果随着死亡时间的推移,大鼠脾脏组织FTIR光谱的主要吸收峰峰位没有明显变化,而其吸收峰强度有明显差异:(1)1080cm-1和1238cm-1被指认核酸谱带吸收峰的峰强呈下降趋势;(2)1541cm-1被指认酰胺Ⅱ吸收峰的峰强呈上升变化;(3)1396cm-1被指认脂肪酸吸收峰的峰强呈上升变化;(4)指认为C-H结构振动的2852、2871、2923、2958cm-1吸收峰的峰强呈现上升趋势。结论 FTIR光谱分析技术有望成为法医死亡时间推断的有效方法。  相似文献   
298.
After 1960s, the economic developmental explosion in Taiwan had brought serious environmental degradations including the air and water pollution, waste disposal, as well as wildlife problems. Since then, Taiwanese has begun environmental protection movements striving for "environmental rights". In addition, international environmental agreements have grown with great speed in the past decades. Although Taiwan never signed or joined any international environmental agreements or organizations, the development of international environmental laws still deeply affect Taiwan environmental regulations. Under this global trend, Taiwan has to cooperate with international community and to obey international environmental agreements. Thus Taiwan had passed numerous environmental laws including "Air Pollution Control Act," "Water Pollution Control Act," "Noise Control Act," "Waste Management Act," "Toxic Chemicals Management Act," "Wildlife Protection Act," and "Nuisance Dispute Resolution Act." Thus the article will examine Taiwan's environmental administration, regulations as well as the implication under international agreements.  相似文献   
299.
从回归分析看中国股票市场中的资本资产定价模型   总被引:1,自引:0,他引:1  
研究资本资产定价模型对分析中国证券市场投资组合的作用和意义。采用回归分析的方法,进行中国证券市场的抽样实证分析,说明通过统计分析的方法,可以选择相对合适的市场组合收益率,提高资产估值和资产配置的准确性。并对我国资本市场应用资本资产定价模型(CAPM)的有效性和及其障碍进行分析。  相似文献   
300.
Body fillers are sometimes encountered with paint evidence from hit-and-run accidents. Little forensic research has been conducted and published on the subject since 1986. The objective of this study was to determine if chemical and physical differences in body fillers from various manufacturers existed and could be identified. Thirty-three samples of light-weight automobile body fillers and spot putties were obtained. The fillers and putties were compared using light microscopy, infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX), and pyrolysis gas chromatography (pyGC). Results from fourier transform infrared spectroscopy analysis placed the samples into five groups and differentiated six samples. Light microscopy placed the samples into one of five color groups. PyGC placed the samples into three groups and differentiated one sample. SEM-EDX placed the samples into four groups and differentiated 13 samples. Using these analysis methods, 19 of the 33 samples could be discriminated. The best discriminatory tool was found to be SEM-EDX.  相似文献   
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