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841.
On the basis of equations of external ballistics and probability theory the largest possible distances of free (independent) flight of gunshot powder and metal particles having different forms and sizes were calculated. Experimental control of the calculated data for different types of battle and sports hand fire-arms was carried out. The correspondence of the calculated data to maximal free (independent) particle flight in blank shots was stated. In experiments with cartridges equipped with bullets the distances of free particle flight were significantly lesser (by 53-65%) which may be connected with effect of gunshot projectile on the process of particle distribution. Reversed adapted formulas and calculation variants are presented. 相似文献
842.
DNA fingerprinting is a perfect tool for investigating the identity of disputed blood by alcohol samples extracted. However, blood samples stored at an ambient temperature for longer periods can show considerable degradation of high-molecular DNA, diminishing the value of fingerprint investigation because of loss of the less frequent bands formed by the longer DNA fragments. Addition of the complexing agent EDTA can retard this degradation. Determination of the sex with DNA probes in the blood alcohol sample increases confidence in the investigation. 相似文献
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Robert A. Leone 《Journal of policy analysis and management》1989,8(4):704-711
Many of the qualities of case method teachitig stem from the classroom method and not merely from the case. This article describes five noncase exercises designed to achieve purposes that cases are often used to accomplish, but which experience indicates, can do the job more easily. They are all based on the proposition that attention to the classroom method and not merely to the case will allow instructors to teach public management more effectively. 相似文献
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