Powerful Explosions Research Articles

The use of cosmic rays for continuous monitoring and prediction of some dangerous phenomena for the earth's civilization

The main idea of the International Cosmic Ray Service (ICRS) is to combine satellite and spaceprobe cosmic rays, magnetic and plasma data with groundbased cosmic ray data (exchanged in real time) for obtaining continuous information on the electromagnetic and radiation situation in the interplanetary space and Earth's magnetosphere: prediction of great geomagnetic storms, big increases of radiation hazards and other dangerous phenomena in space and on the Earth for people and technology. ICRS can predict not only geomagnetic storms and unfavorable days in the environment (especially important for old people and people with some diseases), but, in combination with astrophysical methods, can predict big increases of radiation hazards very dangerous for the Earth's civilization and big changes in the environment due to extremely powerful solar flares and local supernova explosions. We hope that, after some additional investigation of high energy cosmic-ray distribution function outside the heliosphere, it could be possible to solve by ICRS more complicated problems: to determine in combination with astrophysical methods the location and velocity of nearest dust-molecular galactic clouds with frozen-in magnetic fields and predict the expected time of the Sun capturing by some clouds with possible changes of Earth's global climate. The foundation of ICRS could bring a new possibility of development to the cosmic ray observatories, release scientists from a lot of routine work and increase the fundamental and applied research efficiency.

Ionospheric disturbances produced by powerful explosives

Results of a study of wave-like ionospheric disturbances initiated by powerful explosives are presented and analyzed. Three types of wave processes with differing physical natures which propagate in the upper atmosphere and ionosphere to distances of thousands of kilometers are distinguished. The effect of shock-acoustic waves on indirect short wave radio propagation is considered.

Mineral sector technologies: policy implications for developing countries

Over the past 20 years the mining industry has been a leader in the conception and application of advanced technologies. New thinking about earth tectonics as well as advances in geophysics, geochemistry, remote sensing, data processing and communications permit more effective and accurate geological exploration. Mechanization, more durable materials and more powerful explosives, as well as computer aided mine design and management have led to substantial gains in productivity. Minerals processing has similarly seen significant technological advances including solvent extraction, electro‐winning of metal ores, bath smelting techniques, cyanide leach to produce gold, and bioleaching of sulphide and refractory ores. New technologies have dramatically improved mine health and safety as well as making possible control of water and air pollution. Improved communication and transport have stimulated competition and fostered the internationalization of mineral commodity prices. As these technologies are essentially market driven, developing countries should continue current efforts towards economic liberalization. Promoting investment in mining entails lifting many of the restrictions and taxes that can hinder efficient exploration and development. We examine some developments that have greatly increased the efficiency of exploration, mining and marketing. To obtain maximum benefit from many of these technologies requires governments to adopt a wide range of new policies which are examined in some detail.

Geology and geothermal potential of the tecuamburro volcano area, Guatemala

Tecuamburro, an andesitic stratovolcano in southeastern Guatemala, is within the chain of active volcanoes of Central America. Though Tecuamburro has no record of historic eruptions, radiocarbon ages indicate that eruption of this and three other adjacent volcanoes occurred within the past 38,300 years. The youngest eruption produced a dacite dome. Moreover, powerful steam explosions formed a 250 m wide crater about 2900 years ago near the base of this dome. The phreatic crater contains a pH-3 thermal lake. Fumaroles are common along the lake shore, and several other fumaroles are located nearby. Neutral-chloride hot springs are at lower elevations a few kilometers away. All thermal manifestations are within an area of about 400 km 2 roughly centered on Tecuamburro Volcano. Thermal implications of the volume, age, and composition of the post-38.3 ka volcanic rocks suggest that magma, or recently solidified hot plutons, or both are in the crust beneath these lavas. Chemical geothermometry carried out by other workers suggests that a hydrothermal-convection system is centered over this crustal heat source. Maximum temperatures of about 300°C are calculated for samples collected in the area of youngest volcanism, whereas samples from outlying thermal manifestations yield calculated temperatures <- 165° C . An 808 m deep drill hole completed in 1990 to partly test the geothermal model developed from surface studies attained a maximum temperature of almost 240°C. Thus, the possibility of a commercial-grade hydrothermal resource in the area seems high.

Formation of a large radiation-induced fire

In connection with ecological and climatic problems and, in particular, the “nuclear winter” theory much attention has recently been paid to the study of the possible consequences of large fires and explosions [1–5]. Below, on the basis of the model proposed in [6, 7] we investigate the initial stage of development of a fire induced by the light emitted by a powerful explosion in the atmosphere. The situation above the seat of combustion (the aerodynamics of the layer of air adjacent to the ground, the configuration and characteristics of the smoke cloud formed) is analyzed.

Synthesis of Polynitrocompounds from Nitroguanidine

AbstractThe reactions of nitroguanidine (NG) with urotropine or formaldehyde have been studied. The following compounds are synthesized from NG: 6‐nitroimino‐1,3,5‐trinitro‐1,3,5‐triazacyclohexane [2] and a number of itsderivatives; bis(nitroguanidino)methane [9], a valuable intermediate for preparing some high explosives; 1,5‐dinitro‐2,4‐dinitroimino‐1,3,5triazacyclohexane [10] and some of its derivatives via intramolecular cyclization of [9]; 2‐nitroimino‐1,3‐diaza‐5‐oxacyclohexane [15], 1‐(nitroguanidinomethyl)‐2‐nitroimino‐1,3‐diaza‐5‐oxacyclohexyl [14], and bis(2‐nitroimino‐1,3‐diaza‐5‐oxacyclohexyl)methane [16] by reactions of [9] with formaldehyde. Some detonation data of the above compounds are reported. Campounds [2] and [10] are powerful explosives but very unstable thermally and easily hydrolized. However, compounds [14], [15], and [16] possess a better stability than triazacyclic polynitrocompounds containing nitroimino groups, such as [2] and [10].

Isolated Pulmonary Blast Injury in Rats—A New Model Using the Extracorporeal Shock-Wave Lithotriptor

Blast injury to the lungs is one of the most overwhelming threats to survival following exposure to powerful explosions. The pathophysiology of blast injuries differs significantly from other forms of trauma. Using the extracorporeal shock-wave lithotriptor, originally designed for the noninvasive treatment of nephrolithiasis, we were able to produce isolated, typical pulmonary blast effects in rats. The immediate mortality was associated with bilateral pneumothorax and hemothorax. A nonlethal dose of shock waves caused intra-alveolar and intrabronchial hemorrhages and an immediate 2- to 3-fold increase in the lung weight. Additional marked increase in lung weight started 12 to 24 hours later, consistent with the clinical picture of delayed respiratory insufficiency which occurs after a latent period of 12 to 48 hours in many blast casualties. The use of air-containing vest as a protective measure completely prevented blast injury to the lungs.

Preemption and Punitive Damages: The Conflict Continues under FIFRA

Disputes over the allocation of regulatory power between federal and state authorities historically have plagued our system of federalism. The Framers envisioned a federal government that was centralized enough to ensure an effective national government, yet still protective of state autonomy.1 Both the explosion of federal regulatory power during the New Deal era2 and the growth of federal agencies during the 1960s and 1970s3 ostensibly threatened the autonomy of state power in various areas of regulation. The judiciary has responded in part to this tension by applying the doctrine of preemption. This doctrine, which is derived from the supremacy clause of the Constitution,4 determines whether federal or state regulation will reign over an area that both have attempted to control.5 Preemption has served to allocate regulatory

The Productivity Slowdown, Measurement Issues, and the Explosion of Computer Power

The Productivity Slowdown, Measurement Issues, and the Explosion of Computer Power

A giant intergalactic H I bubble near Arpl43

We present observations of the nearby ring galaxy Arpl43 (NGC2445/4) and describe the discovery of a giant H I shell 20 kpc across, lying 100 kpc from Arpl43. The shell, which shows evidence for line splitting near its centre, lies in a long H I filament pointing towards the Arpl43 system. We suggest that the shell is an expanding bubble of H I, and is direct evidence for a powerful galactic-scale explosion 108 years ago which we associate with a strong burst of star formation. We believe that both the ring galaxy and the giant bubble have their origin in the passage of a gas-rich companion through the inner disk of NGC2445, and its subsequent disruption.

Volcanic hazards from Bezymianny- and Bandai-type eruptions

Major slope failures are a significant degradational process at volcanoes. Slope failures and associated explosive eruptions have resulted in more than 20 000 fatalities in the past 400 years; the historic record provides evidence for at least six of these events in the past century. Several historic debris avalanches exceed 1 km3 in volume. Holocene avalanches an order of magnitude larger have traveled 50–100 km from the source volcano and affected areas of 500–1500 km2. Historic eruptions associated with major slope failures include those with a magmatic component (Bezymianny type) and those solely phreatic (Bandai type). The associated gravitational failures remove major segments of the volcanoes, creating massive horseshoe-shaped depressions commonly of caldera size. The paroxysmal phase of a Bezymianny-type eruption may include powerful lateral explosions and pumiceous pyroclastic flows; it is often followed by construction of lava dome or pyroclastic cone in the new crater. Bandai-type eruptions begin and end with the paroxysmal phase, during which slope failure removes a portion of the edifice. Massive volcanic landslides can also occur without related explosive eruptions, as at the Unzen volcano in 1792. The main potential hazards from these events derive from lateral blasts, the debris avalanche itself, and avalanche-induced tsunamis. Lateral blasts produced by sudden decompression of hydrothermal and/or magmatic systems can devastate areas in excess of 500km2 at velocities exceeding 100 m s−1. The ratio of area covered to distance traveled for the Mount St. Helens and Bezymianny lateral blasts exceeds that of many pyroclastic flows or surges of comparable volume. The potential for large-scale lateral blasts is likely related to the location of magma at the time of slope failure and appears highest when magma has intruded into the upper edifice, as at Mount St. Helens and Bezymianny. Debris avalanches can move faster than 100 ms−1 and travel tens of kilometers. When not confined by valley walls, avalanches can affect wide areas beyond the volcano's flanks. Tsunamis from debris avalanches at coastal volcanoes have caused more fatalities than have the landslides themselves or associated eruptions. The probable travel distance (L) of avalanches can be estimated by considering the potential vertical drop (H). Data from a catalog of around 200 debris avalanches indicates that the H/L rations for avalanches with volumes of 0.1–1 km3 average 0.13 and range 0.09–0.18; for avalanches exceeding 1 km3, H/L ratios average 0.09 and range 0.5–0.13. Large-scale deformation of the volcanic edefice and intense local seismicity precede many slope failures and can indicate the likely failure direction and orientation of potential lateral blasts. The nature and duration of precursory activity vary widely, and the timing of slope faliure greatly affects the type of associated eruption. Bandai-type eruptions are particularly difficult to anticipate because they typically climax suddenly without precursory eruptions and may be preceded by only short periods of seismicity.

Mechanism of longwave acoustic perturbation generation in the atmosphere by a floating cloud of explosion products

Powerful air explosions are accompanied by the formation of intense shock, infrasonic, and gravitational waves in the atmosphere. In this paper the authors construct a model describing the pressure and temperature effects arising from clouds of explosion products and the propagation of these waves from intense chemical and nuclear atmospheric explosions.

Powerful water-plasma explosions

The experiments described in this letter form a continuation of previously outlined research on electrodynamic explosions in liquids. Current pulse amplitudes have been increased from hundreds of ampere to 25 kA. The most powerful explosion so far observed imparted an impulse of 7 N s to a metallic projectile of 1.6 kg mass. The strengths of the impulses scaled proportionally to the electrodynamic action integral. For an arbitrarily chosen current pulse shape and magnitude, the plasma explosion in saltwater is much more powerful than the action of a railgun.

Halifax and the Precipitate Birth of Pediatric Surgery

Several years ago, while attending the annual music festival in Marlboro, VT, I had the good fortune to renew acquaintanceship with Dr Robert Gross, who was living nearby in retirement. When I had been a Senior Medical Resident at Children's Hospital Medical Center in Boston in 1951, Dr Gross was Chief of Surgery and was justifiably regarded as the leading pediatric surgeon of his era. The textbook on pediatric surgery, which he had co-authored years earlier with his predecessor, Dr William Ladd, was considered the authoritative reference on the subject. In those days, we medical residents did not have too much contact with the senior surgeons, and we were certainly overawed by Dr Gross. Thus, I was amazed that some 25 years later Dr Gross seemed to remember that I had moved from Montreal to Halifax a few years earlier. "I suppose you know," he said, "that Halifax was the birth place of pediatric surgery as a specialty." This announcement came as a revelation, and on subsequent inquiry, I discovered that it was also news to fellow pediatric Haligonians, both medical and surgical. Dr Gross informed me that the seminal event was the great Halifax Explosion of 1917—a tragedy whose anniversary is still marked annually in Halifax. On December 6, 1917, a French munitions ship, the Mont Blanc collided with the Norwegian vessel, Imo, in the narrows of Halifax harbor. There resulted the most powerful man-made explosion in history prior to the detonation of the first atomic bomb at Hiroshima. Almost 2,000 men, women, and children were killed and 9,000 were injured, including 199 who were blinded.

An Instrument for the Measurement of Infrasounds and Subsonic Disturbances in the Atmosphere

The physical properties and propagation characteristics of infrasound and subsonic disturbances in the atmosphere determine the technique and instrumentation of their measurements. Infrasounds are characterized by their propagation velocities close to acoustic velocity but frequencies less than that of audible sound, while the subsonic disturbances refer to disturbances having both frequency and propagation velocity below those of audible sound. The sources of both types of disturbances include many geophysical phenomenon as well as powerful explosions, supersonic vehicles etc. A microbarograph recording system has been described to record pressure variations caused by these disturbances. The system includes the micrograph transducer, its calibration assembly and associated electronics. The transducer uses sensitive bellows to sense the atmospheric pressure and a variable reluctance transducer converts the movements of the bellows into electrical signal. The frequency response of the system is determined ...

The explosion of resin moulded power integrated circuits and the corresponding countermeasures: Masaaki Isagawa, Yuzi Iwasaki and Tamotsu Sutoh. Microelectron. Reliab.20, 625 (1980)

The explosion of resin moulded power integrated circuits and the corresponding countermeasures: Masaaki Isagawa, Yuzi Iwasaki and Tamotsu Sutoh. Microelectron. Reliab.20, 625 (1980)

Supernova Explosions - The Role of a Rayleigh-Taylor Instability

AbstractA two dimensional hydrodynamic study indicates that convectively unstable gradients which develop during core collapse and bounce give rise to large scale core overturn. It is also shown that the concomitant release of neutrini can deposit large amounts of energy and momentum in the infalling envelope and give rise to a powerful supernova explosion.

Evaluation of hazards from industrial activities near nuclear power plants — deterministic and probabilistic studies

Among the potential hazards which could arise from industrial activity near nuclear power plants, fires and explosions of dangerous products are of particular concern. Indeed, thermal radiation from an adjacent fire could endanger the resistance of a plant's structures. Likewise, an accidental explosion would induce an overpressure wave which could affect buildings' integrity. This paper presents the methodology developed by Electricité de France to evaluate the consequences of accidents affecting: • - Industrial facilities: refineries, chemical and petrochemical plants, storage areas, pipelines of gaseous, liquid and liquefied materials. • - Transportation routes (roads, railways, inland waterways) used to carry dangerous substances (solid explosives, liquid, gaseous or liquefied hydrocarbons). Probabilistic methods have been developed by analysis of actual accident statistics (e.g. risks induced by transportation routes) and realistic and representative accident scenarios have been set up. Five sequences have been identified: • - Formation of a fluid jet at a breach. • - Evaporation and possible formation of a liquid layer. • - Atmospheric dispersion and drift of a gaseous cloud. • - Heat radiation from fire. • - Unconfined explosion of a gaseous cloud. This paper gives an overview of the methods and the main assumptions used to deal with each sequence. Those methods, presently applied by Electricité de France, provide a coherent and realistic approach for the evaluation of the risks at nuclear power plants induced by industrial activity.

Nuclear weapons and power-reactor plutonium

With modest design sophistication, high-burn-up plutonium from power reactors can produce powerful and predictable nuclear explosions. There is no way to ‘denature’ plutonium. Power reactors are not implausible but rather attractive as military production reactors. Current promotion of quasi-civilian nuclear facilities rests, dangerously, on contrary assumptions.

The explosion of resin moulded power integrated circuits and the corresponding countermeasures

Product Liability (PL) is one of the most serious problems at the present time, but the interest in it is mainly concerned with systems. The authors point out in this paper that one of PL problems is in the parts, namely, the explosion of resin moulded power integrated circuits. There are a few chances of explosion during the test of the units or sets into which they are assembled, due to misoperations such as shorting between the adjacent pins. At that time, a bonding wire or IC chip is overheated due to abnormally high current or power, then the resin fragment just above it is blown off into the air, sometimes burning. This situation is very dangerous and considered to have a possibility of someone becoming blinded. We clarified the explosion mechanism and present some counter-measures to prevent the explosion accident, i.e. some methods of explosion free devices and techniques preventing such accidents.