Volatile organic compounds from the combustion of human and animal tissue

The volatile by-products of the combustion of ordinary fuels such as wood, polystyrene, polyethylene, urethane foam, PVC and the like are well known to the forensic fire debris examiner. When a fire involves a human body, volatile species are produced that are not so well known, including various alkenes and aldehydes. These have sometimes been mistaken for the residues of unusual accelerants. In an attempt to document what volatiles are produced by the combustion of animal fat and human fat, the authors have used an open-tube pyrolysis probe as a microfurnace to burn small samples of unembalmed subcutaneous fat from human, avian and porcine sources, and collect volatiles by charcoal strip adsorption. The volatile products were analyzed by GC/MS. Predominant species included aldehydes in the C6-C10 range, homologous series of alkenes and alkanes, and other hydrocarbon products. These results were compared to those obtained by free-burning (open flame in air) of similar specimens and to the volatiles detected in debris from beneath a human cadaver in a test fire. Differences between the volatile profiles produced by human fat as compared to pork and chicken fat and adventitious sources of such volatiles are discussed.     

Evaluation of the self-heating tendency of vegetable oils by differential scanning calorimetry

The evaluation of the self-heating propensity of a vegetable (or animal) oil may be of significant importance during the investigation of a fire. Unfortunately, iodine value and gas chromatographic-mass spectrometric analysis do not lead to meaningful results in this regard. To the contrary, differential scanning calorimetry (DSC), which does not measure the chemical composition of the oil, but rather its thermodynamic behavior, produces valuable results. After a thorough literature review on the autooxidation of vegetable oils, several oils with different self-heating tendencies were analyzed using a Mettler-Toledo differential scanning calorimeter DSC 25 between 40 degrees C and 500 degrees C. Analyses were carried out both under air and nitrogen atmosphere to identify the phenomena due to autooxidation reactions. Using DSC, it was possible to observe the induction period of the oil (when available), the three different exothermic events, and the autoignition temperature (relatively independent of the oil type).     

我国监察侦查的学理展开

《中华人民共和国宪法修正案》(以下简称《宪法修正案》)的通过、《中华人民共和国监察法》(以下简称《监察法》)的制定、《中华人民共和国刑法诉讼法》(以下简称《刑事诉讼法》)的修改,标志着我国反腐法治化的进一步发展,将检察机关对“贪污贿赂犯罪和国家工作人员的渎职犯罪”案件的侦查权剥离给监察委员会,由监察机关按照《监察法》的内在逻辑对这些犯罪行使“调查权”,实质是将监察权引入刑事诉讼,监察机关对这些职务犯罪的调查权实质是“侦查权”。按照刑事侦查一般原理,以及我国刑事司法全面法治化的推进逻辑,特别是刑事诉讼宪法化的内在要求,《刑事诉讼法》与《监察法》未来发展需要对监察机关“调查权”一并进行调整,要围绕“侦查权”双向落位重塑“调查权”,要做到授权与控权同时并举,进一步规范立案机制,完善侦查原则,优化侦查构造,规范侦查行为。监察侦查权的法治化,既伴随着再次修宪中检察权的适度调适,也伴随着《刑事诉讼法》与《监察法》相应一并修改时检察机关侦查监督权的适度拓展。     

低NOx浓淡火焰对冲燃烧技术及装置的研究

分析ＮＯｘ的形成与危害，研究浓淡火焰对冲燃烧抑制ＮＯｘ生成机理，探讨浓淡火焰对冲燃烧技术与装置。