Download or read book Air Blast Studies with Animals II written by R. S. Anderson and published by . This book was released on 1961 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: The damage to be expected in man from exposure to long-duration blasts is important because of the threat of fission or fusion bombs, and is not well known. As a result of previous work, the large shock tube at the Ballistic Research Laboratories, Aberdeen Proving Ground, was judged suitable, after modification, for obtaining additional information. The velocities of goats (under Nembutal) and a dummy blown from the shock tube were measured under various conditions. At a given tube stage and overpressure, the major variable determining the velocity was the initial orientation of the goat or dummy. The distance thrown was related in a fairly regular way to the velocity.
Download or read book Initial Studies of the Effect of Laboratory produced Air Blast on Animals written by Benedict Cassen and published by . This book was released on 1949 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Direct Air Blast Exposure Effects in Animals Operation Upshot Knothole Project 4 2 written by and published by . This book was released on 1953 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Project 4.2 was designed to study direct (primary) air blast injury, in animals, from an atomic weapon in the range of 20 to 50 psi under circumstances affording protection against missiles, thermal and ionizing radiation and to estimate the probable direct air blast hazard in man. The pressure levels at which atomic weapons direct air blast injuries occur will determine, to a large extent, the number of blast casualties likely to be encountered. It is probable that fatal overpressures are not reached until well within the range at which indirect (secondary) blast, thermal and ionizing radiation are practically certain to prove fatal. Only in special situations affording partial protection from other injuries are blast injuries likely to be of practical importance. Two animal species of widely different body weights (700 rats and 56 dogs) were exposed, together with air pressure recorders, in aluminum cylinders, covered by sandbags and dirt but open at both ends, at seven stations distributed within the intended overpressure range of 20 to 50 psi of Shot 10"About 200 rats were likewise exposed in Shot 9. Unfortunately, the destructive effect of the air blast of Shot 10 was much greater than anticipated. Many of the exposure cylinders were displaced and their contents destroyed. Only a partial recovery of the animals was possible due to the excessive radioactive contamination which greatly limited the time in the area. Most of the animals were dead upon recovery. Those living were in a state of severe shock. Autopsy findings showed remarkably few traumatic lesions and lung hemorrhages in spite of the rough treatment and high overpressure to which they were subjected. The rats recovered from Shot 9 were exposed to a recorded pressure of 18 to 2k psi. The autopsy findings showed moderate lung hemorrhage in most of the animals undoubtedly due to direct air blast injury. The findings were typical of those seen following exposure to air blast from HE or in the shock tube. The agreement between the estimated pressures and the recorded pressures in the containers were good in some instances but not in others. Discounting the initial pressure rise, it was thought that the records represent the pressure changes in the exposure containers. The individual records exhibited rather wide variations in recorded pressures indicating a complex pressure field. The attempt to compare levels of direct air blast in small and large animals, and thereby to extrapolate to man, was not accomplished due to the lack of statistically reliable data on the dogs. The lapse of time between the death of the dogs and autopsy reduced the interpretable findings below the level required for statistical significance. Laboratory studies are planned to evaluate the relative importance of the several blast wave parameters in the production of injury, Recommendations for future field test studies will depend upon the outcome of this laboratory work.
Download or read book Blast induced Translational Effects written by E. Royce Fletcher and published by . This book was released on 1966 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mathematical model was developed to predict the time displacement histories of objects translated by the blast winds from conventional or nuclear explosions; these predictions were then compared to actual experiments. The objects studied varied in size from 139 mg spheres to man and were all assumed to be free to move over a smooth horizontal surface. The effects of ground friction could either be included or neglected, but when they were considered the ground friction eventually brought the objects to rest after the winds had passed. The values of ground friction used were determined experimentally and were found to be functions of the velocity and mass of the object being displaced. The translational model was general enough for either classical or nonclassical blast waves to be considered. Results for a chemical explosion were obtained by using both the computed blast waves of various authors and the experimentally determined blast waves. These predicted results were compared with each other as well as with experimental data obtained with steel spheres. The model was used to determine dynamic pressure impulses necessary to explain the measured sphere velocities at three ranges from ground zero. Another mathematical model was briefly described which was developed to compute the detailed two-dimentional trajectories of objects as they roll, slide, and bounce along the ground. The model closely predicted the measured distances between bounces and the total displacements of concrete blocks and large stones and thus helped to explain the mechanisms of tumbling by which an irregular object may become airborne during both the accelerative and the decelerative phases of displacement.
Download or read book The Effects of Shock Tube Generated Step rising Overpressures on Guinea Pigs Located in Shallow Chambers Oriented Side on and End on to the Incident Shock written by Victor R. Clare and published by . This book was released on 1962 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: A total of 308 guinea pigs were exposed to air blast in 4 close-fitting, shallow, rectangular chambers mounted on the top, bottom and sides of an air-driven shock tube. With a reflecting plate at the downstream edge of the chambers, the animals were exposed to long-duration shock overpressures that initially rose in a single step. The LD50-24-hr reflected pressure calculated from grouping all positions was 36.2! 0.8 psi. By moving the reflecting plate to various distances downstream of the chambers, shock overpressures that initially rose in two steps were applied. The results were that the animals' tolerances to overpressure rose as the time between pressure steps was increased. Comparison of the LD50's obtained with animals in each chamber revealed that there was not a significant statistical difference in their tolerances, whether they were loaded initially with the single-step pulse from their right, left, dorsal or ventral surfaces. (Author).
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1971-04 with total page 1658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Abstract Bulletin written by Defense Documentation Center (U.S.) and published by . This book was released on 1961-07 with total page 1766 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Tolerance of Guinea Pigs to Air Blast when Mounted in Shallow Deep and Deep with offset Chambers on a Shock Tube written by Donald R. Richmond and published by . This book was released on 1962 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: One hundred and eighteen guinea pigs were exposed to air blast in shallow, deep, and deep-with-offset chambers mounted on a shock tube. The LD(50)- 24 hours, in terms of the incident shock pressures measured adjacent to the chambers, was calculated by probit analysis to be 34.9 psi, 19.5 psi, and 26.8 psi for animals in the shallow, deep, and deep-with-offset chambers, respectively. According to the LD(50) incident pressures, the shallow chambers offered the most protection against air blast; the deep chambers, the least. Comparing the LD(50)pressure dose at the animals' location revealed little difference in their tolerance to overpressure, per se; i.e., LD(50) reflected pressures measured by gauges within the deep and deep-with-offset chambers were 34.6 psi and 35.9 psi, respectively. The LD(50) incident shock pressure of 34.9 psi in the shallow chambers was considered to be the dose at the animal's location in that instance. The protection against blast provided by the three chambers and the response of animals to the particular pressure time patterns encountered are discussed.
Download or read book The Acute Effects of Air Blast on Pulmonary Funcion in Dogs and Sheep written by Damon Edward G. and published by . This book was released on 1970 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pulmonary function tests were conducted before and after exposure of animals to air blasts produced in shock tubes or by high explosives. Pressure- time measurements were made with piezoelectric pressure transducers during each air-blast exposure. Blood samples were obtained without anesthesia from an indwelling arterial catheter. The blood PO2, PCO2, and pH and the end-tidal and mixed expired CO2, O2, and N2 gas concentrations were measured for subjects breathing air and oxygen. There were increases in the alveolar-arterial O2 differences and venous admixture which generally correlated with the extent of blast-induced lung damage. The threshold for lung injury resulting in increased venous admixture in sheep was about 20 psi for reflected overpressures of 'long' duration. Pressures above 43 psi usually caused severe lung damage in which the venous-arterial shunt exceeded 30 percent of the cardiac output, a condition in which the arterial oxygen tension was below the level required for full saturation of the hemoglobin even with animals breathing pure oxygen.
Download or read book United States Naval Medical Bulletin written by and published by . This book was released on 1946 with total page 1344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomedical Research Studies in Acceleration Impact Weightlessness Vibration and Emergency Escape and Restraint Systems written by and published by . This book was released on 1963 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research Reports written by and published by . This book was released on 1964 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Medical Research written by Francis Henry Knethell Green and published by . This book was released on 1953 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the researches in medical science promoted by the Medical Research Council and by various government department during [the war]
Download or read book Consolidated R D Annual Project Report written by United States. Army. Quartermaster Corps and published by . This book was released on 1956 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Explosive Decompression Component of Air Blast written by R. H. Lee and published by . This book was released on 1959 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Review of the Effects of Aircraft Overflights on Wildlife written by Ann E. Bowles and published by . This book was released on 1994 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Prevention of and Protection Against Accidental Explosion of Munitions Fuels and Other Hazardous Mixtures written by New York Academy of Sciences and published by . This book was released on 1968 with total page 930 pages. Available in PDF, EPUB and Kindle. Book excerpt:
