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981.
982.
Jamie M. Baerncopf B.S. Victoria L. McGuffin Ph.D. Ruth W. Smith Ph.D. 《Journal of forensic sciences》2011,56(1):70-81
Abstract: In fire debris analysis, weathering of ignitable liquids and matrix interferences can make the identification of ignitable liquid residues (ILRs) difficult. An objective method was developed to associate ILRs with the corresponding neat liquid with discrimination from matrix interferences using principal components analysis (PCA) and Pearson product moment correlation (PPMC) coefficients. Six ignitable liquids (gasoline, diesel, ultra pure paraffin lamp oil, adhesive remover, torch fuel, paint thinner) were spiked onto carpet, which was burned, then extracted using passive headspace extraction, and analyzed by gas chromatography‐mass spectrometry. Both light and heavy burn conditions were investigated. In the PCA scores plot, ignitable liquids were discriminated based on alkane and aromatic content. All ILRs were successfully associated with the corresponding neat liquid using both PCA and PPMC coefficients, regardless of the extent of burning. The method developed in this research may make the association of ILRs with corresponding neat liquids more objective. 相似文献
983.
Sweden is no longer a negative, exceptional case regarding the presence of radical right‐wing populist parties. The Sweden Democrats has continually grown stronger, and in 2010 they won seats in the Swedish parliament. However, their electoral support varies considerably across Sweden. This study analyses their electoral support in 290 Swedish municipalities in order to explain this variance. Support is found for the social marginality hypothesis: electoral support for the Sweden Democrats tends to be negatively correlated with the average level of education and with the Gross Regional Product per capita, and positively correlated with the unemployment rate. The ethnic competition hypothesis, that there is a positive correlation between the proportion of immigrants and electoral support of the Sweden Democrats, is also supported. 相似文献