Challenger explosion

Accidental or uncontrolled explosions can have disastrous effects. Spectacular explosions of various types gain widespread attention. One of the most notable was the space shuttle Challenger explosion on live television in 1986. Others are grain elevator explosions and explosions of railroad tank cars and storage vessels containing liquid petroleum gas (LPG) and other materials. Although the visible effects appear similar, the phenomena are not exactly alike. 

This group decision was perhaps the real cause of the Challenger explosion. This and other historical fiascoes, including failure to anticipate the Japanese attack on Pearl Harbor, the Bay of Pigs invasion of Cuba, the escalation of the Vietnam war, the Watergate cover-up, the Iran-Contra affair, and the Chernobyl reactor tragedy, resulted from teams of well-intentioned professionals making imwise and at-risk decisions. 

The Challenger explosion was caused by a single, catastrophic malfunction the O-rings that were supposed to prevent hot gases from leaking out of the rocket boosters did not do their job. 

Galvin, Molly, PE perseveres, 10 years after Challenger explosion. Engineering Times, National Society of Professional Engineers, August 1995. 

Ha/ogenation. Heats of reaction are highly exothermic for halogens, particularly fluorine (qv), and chain reactions can result in explosions over broad concentration ranges. Halogens also present severely challenging corrosion problems (see Corrosion and corrosion control). 

The recent rise in the use of expolosives in terrorist activity poses new challenges to industry and law enforcement. This challenge is being met by the use of sophisticated chemical detection devices to screen for bombs and more rigorous explosive inventory safeguards and controls. Plans have also been proposed to tag explosives with isotopes to make them easier to trace if misused. 

When the Plutonium Project was established early in 1942, for the purpose of producing plutonium via the nuclear chain reaction in uranium in sufficient quantities for its use as a nuclear explosive, we were given the challenge of developing a chemical method for separating and isolating it from the uranium and fission products. We had already conceived the principle of the oxidation-reduction cycle, which became the basis for such a separations process. This principle applied to any process involving the use of a substance which carried plutonium in one of its oxidation states but not in another. By use of this... 

Benchmark 2 continues the emphasis on persistence, bioaccumulation, and toxicity, but at lower threshold values. In addition. Benchmark 2 includes flammability and explosiveness. It is anticipated that many chemicals will not move past Benchmark 2 because of the broad scope of hazards and challenging threshold values included in the Green Screen. 

Richard Feynman loved to play the bongos. He also loved solving problems. He figured out the reason for the space shuttle Challenger s 1986 explosion by showing that cold weather caused the rubber seals of the booster rocket to fail. Feynman was one of the twentieth century s great theoretical physicists, a Nobel Prize winner who spent much of his career studying atoms. He knew as much about atoms as anyone in the world, and this is what he said about them in his book Six Easy Pieces ... 

The main challenge in short-term scheduling emanates from time domain representation, which eventually influences the number of binary variables and accuracy of the model. Contrary to continuous-time formulations, discrete-time formulations tend to be inaccurate and result in an explosive binary dimension. This justifies recent efforts in developing continuous-time models that are amenable to industrial size problems. 

The relative rarity of dust and powder ignitions makes them a unique sort of industrial safety threat. Because their occurrence is not routine, operating personnel eventually relax their guard, and too often this sort of behavior leads to dangerous incidents. The evidence that dust explosions are almost unknown within fluidized beds is an especially challenging problem for the safety officer, who must encourage vigilance even when no one remembers the last electrostatic incident. 

Riley J (2001a) The indicator explosion local needs and international challenges. Agric Ecosys Environ 87 119-120... 

Proper application of these concepts in the plant environment The technology does exist to handle and process flammable and explosive materials safely, and to mitigate the effects of an explosion. The challenges to this problem are as follows ... 

The intense initial heat lasts several seconds and the initial radiation lasts only a few minutes. Seek shelter behind some solid barrier (i.e., a brick wall or subway tunnel) as soon as possible to avoid high radiation doses and thermal burns. Hopefully, this solid barrier will also be able to endure the coming air blast. An air blast from a nuclear explosion travels at approximately 5 miles per second and carries with it glass, metal, or any debris in its path. By immediately retreating behind a solid barrier, individuals can avoid exposure to the initial heat and radiation and hopefully survive the air blast. The next challenge is seeking long-term shelter to avoid the radiation from fallout. 

Scheme 9.1 shows a generalized sequence of reactions for the oxidation of an alkane, via alcohol, ketone and carboxylic acid, to the completely oxidized products, water and carbon dioxide. The latter are often referred to as combustion products as they are the same as those formed by burning hydrocarbons. These are not normally desirable chemical products unless it is necessary to destroy a toxic, hazardous or otherwise unwanted waste material. Oxidation itself is not difficult to achieve, and is a highly exothermic or even explosive process. Selective oxidation, however, is a much greater challenge, as it is important to stop the sequence at the desired product without proceeding further down the oxidation pathway. 

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