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V I Savich Kh A Valladares Iu A Gusakov Z M Skachko 《Sudebno-meditsinskaia ekspertiza》1990,33(4):24-27
Gas-chromatographic method of acetaldehyde detection in blood of subjects who died of alcoholic intoxication is suggested. Method is simple, does not require additional expenses, can be readily used in medicolegal practice and in difficult cases it may help the expert to make an objective conclusion on the cause of death. 相似文献
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Kazimierz Z. Poznanski 《Economic Change and Restructuring》1990,23(2):129-141
The purpose of this study is to compare the speed of diffusion in major steel-making countries. This is a cross-system analysis, involving industrial market countries (Western Europe, the United States, Canada, and Japan), quasi-market economies (selected newly industrializing countries, India), and the central planning states (the Soviet Union and Eastern Europe). The study reveals that at least in this, significant case, the latter countries are clearly inferior, i.e. slower. The article seeks the most accurate measure of speed of diffusion of one radical steel innovation, the oxygen process. The speed is estimated by regressing a logistic function not applied to the steel industry to date. Parameters of a logistic function are estimated first with linear least squares methods and then with nonlinear (or iterative) least squares, to establish which offers more accurate estimation than the widely used linear approach. It is shown that the iterative method produces a better statistical fit. 相似文献
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An experimental study was done to determine the diameter and velocity of blood drops falling on a surface by measuring the size of bloodstains they produced and counting the number of radial spines projecting from them. Bloodstains were formed by releasing drops of pig blood with a range of diameters (3.0-4.3 mm) and impact velocities (2.4-4.9 m/s), onto four different flat surfaces (glass, steel, plastic, paper) with varying roughness (0.03-2.9 microm). High-speed photography was used to record drop impact dynamics. Bloodstain diameters and the number of spines formed around the rim of stains increased with impact velocity and drop diameter. Increasing surface roughness reduced stain diameter and promoted merging of spines, diminishing their number. Equations are presented that explicitly relate drop diameter and impact velocity to measurements of stain diameter and number of spines. 相似文献