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231.
Dried, treated wood was sealed with Thompson's WaterSeal "Clear Multi-Surface Waterproofer" and exposed to outdoor, summer conditions. Sections of the sealed wood were then periodically tested and analyzed in accordance with ASTM methods. The WaterSeal contained a medium petroleum distillate (MPD) as a solvent for a wax. The treated lumber contained a background of aldehydes that could mimic a dearomatized MPD if not carefully investigated by the analyst. The MPD of the WaterSeal was detectable 14 days, but not 27 days after application with exposure to relatively hot, dry and sunny weather conditions. The test was repeated with the MPD detectable 16 days, but not 20 days after application with exposure to cooler and wetter weather conditions. The testing demonstrates the need for a thorough and complete investigation by the fire investigator and the submission of comparison samples to the laboratory. 相似文献
232.
Latkoczy C Becker S Dücking M Günther D Hoogewerff JA Almirall JR Buscaglia J Dobney A Koons RD Montero S van der Peijl GJ Stoecklein WR Trejos T Watling JR Zdanowicz VS 《Journal of forensic sciences》2005,50(6):1327-1341
Forensic analysis of glass samples was performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) systems. The main objective of the interlaboratory tests was to cross-validate the different combinations of laser ablation systems with different ICP-MS instruments. A first study using widely available samples, such as the NIST SRM 610 and NIST SRM 612 reference glasses, led to deviations in the determined concentrations for trace elements amongst the laboratories up to 60%. Extensive discussion among the laboratories and the production of new glass reference standards (FGS 1 and FGS 2) established an improved analytical protocol, which was tested on a well-characterized float glass sample (FG 10-1 from the BKA Wiesbaden collection). Subsequently, interlaboratory tests produced improved results for nearly all elements with a deviation of < 10%, demonstrating that LA-ICP-MS can deliver absolute quantitative measurements on major, minor and trace elements in float glass samples for forensic and other purposes. 相似文献
233.
There have long been calls for the reduction of coercion in treating civilly committed psychiatric patients. The present study assessed whether a minor procedural change intended to reduce the adversarial nature of the treatment process would have a positive impact. Results suggested that the change in procedure had a positive effect for the most direct outcome variables but results were more mixed for the indirect outcome variables. Nonetheless, overall indications were that the change of procedure affected patient outcome. 相似文献
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Public Choice - The tax rule suggested by Groves and Ledyard is certainly an ingenious one, although there is no indication as to how one might fall upon that specific scheme. If offers Pareto... 相似文献
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Robert L. Llneberry 《政策研究评论》1985,4(3):407-411
Policy scientists can make important contributions to the study of policy distribution, a question that is likely to be among the most crucial national issues to be discussed throughout this decade. One aspect of this question that has been neglected is the theoretical assumption associated with public choice theory that politicians, once elected, will reward their supporters through the distribution of policy benefits. However, empirical research indicates that policy benefits seldom are distributed in this way. Instead, politicians follow the principle of universalism. In league with bureaucracies and policy communities, politicians define need and then ask bureaucracies to allocate benefits. This makes politicians roles as distributors of policy very different than simplistic models suggest. 相似文献
238.
Food cooperatives have played a vanguard role in consumer protection through (a) information and education, (b) selective merchandising and boycotts, and (c) political lobbying. While education and selective merchandising benefit primarily their own membership, the political efforts have benefited all consumers. 相似文献
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