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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
922.
UNEMPLOYMENT, SCHOOL LEAVING, AND CRIME 总被引:2,自引:0,他引:2
923.
Fifty-eight garments were taped and searched for mid to dark blue wool fibres. These were then removed from the tapings, mounted on slides and examined using a high-power microscope (400x). A total of 2,740 blue wool fibres were identified and visible range microspectrophotometry (MSP) was performed on them. Three hundred independent blue wool populations were identified on 56 of the 58 garments searched. The lack of control fibres meant the spectral range of each population was unknown. The number of populations may have been underestimated by grouping together the fibres that had broad single peaks and a lack of distinguishing features in the spectra. Although blue wool is considered to be a common fibre type, 300 unique spectral shapes were identified by the use of microspectrophotometry alone. This demonstrates that the dyes used in the dyeing of blue wool are variable. Showing that many different populations of blue wool occur on a range of garments should ensure that the forensic scientist does not underestimate or understate the strength of evidence in cases where blue wool is found. Hopefully this work will enlighten scientists and enable them to also assess the true value of their findings when other commonly occurring fibres are encountered. 相似文献
924.
21世纪初西伯利亚和远东的地理政治与地理经济作用正逐渐增长,太平洋地区国家对该地区的兴趣和关注也在飞速增长.莫斯科、北京和华盛顿在广袤的西伯利亚和远东的利益将如何部署,这种部署会建立在合作的基础之上还是会成为引发各种冲突表现的主要原因?它将怎样影响在太平洋地区和全世界的国际关系?一种关于"俄中美三角关系"在西伯利亚和远东广大地区相互作用之前景的观点得出了关于潜在冲突的结论,这种潜在的冲突埋伏在三方态度和利益的差异上.在太平洋地区潜在的国家利益和全球及地区力量分配的改变可能会给三方利益和立场的确定带来调整. 相似文献
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926.
V. Auwaerter M. Grosse Perdekamp J. Kempf U. Schmidt W. Weinmann S. Pollak 《Forensic Science International Supplement Series》2007,170(2-3):139
A 23-year-old man was found on a raised hide in lying position, the head wrapped in a plastic bag connected with a helium gas cylinder by a polypropylene tube. The autopsy did not show any specific findings nor did the routine toxicological analysis reveal significant information regarding the cause of death (BAC 0.9 mg/g, diphenhydramine 0.81 μg/ml in heart serum). For the detection of helium in the lungs, gas samples from both lungs were collected by a method ensuring minimal dilution. Gas analyses were performed using a GC–MS with a split–splitless injector and a headspace syringe. As carrier gas the commonly used helium was replaced by nitrogen. Helium was found in clearly elevated concentrations in gas samples from both lungs. Therefore, suffocation by breathing helium enriched, and thus oxygen deficient atmosphere, can strongly be assumed as the cause of death. 相似文献
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WILLIAM P. AVERY 《Political science quarterly》1998,113(2):281-305