After several iterations of the process the scientists boosted the yield to 44 percent. The full chemical name is bis 1,2,4-oxadiazole bis methylene dinitrate. Research will continue with production of the material on a kilogram scale, a battery of explosive testing as well as future toxicity studies.
The Environmental Protection Agency has listed TNT as a possible carcinogen, and exposure to the material has been linked to disorders of the blood, such as anemia, and abnormal liver function, according to the Centers for Disease Control. TNT has been in use as a munitions explosive since Captions for images below: Oxadiazole has a calculated detonation pressure 50 percent higher than that of TNT. It was nearly 20 years before it was discovered to be an excellent high explosive.
At that time, 2,4,6-trinitrophenol, a molecule with a similar structure, was the best high explosive around. Better known as picric acid, it had a downside, as dry picric acid is very shock-sensitive. Moreover, it's acidic, so that it slowly corroded metal casings, forming metal salts that are even more shock-sensitive than the free acid. TNT had several advantages over other explosives.
Although it is not as strong an explosive as picric acid, it was much safer to handle and harder to detonate. Because of its melting point of only 80? C, it became possible to fill shells safely with molten TNT. The German military started using TNT as their standard explosive in , whilst the British stuck with picric acid, a choice with unfortunate consequences.
TNT-filled shells are more likely to penetrate armour before exploding, and they also produce a very high velocity shockwave. In contrast, shells filled with the more sensitive picric acid did not penetrate armour, but exploded on contact, causing less damage.
This was part of the reason for the Royal Navy suffering greater losses than the Germans at the Battle of Jutland in The first world war resulted in an intense demand for toluene, which was not just needed for the manufacture of TNT, but was also involved in the synthesis of many dyes.
This not only helped the toluene go further but had an added bonus. One disadvantage of TNT is that the molecule does not contain enough oxygen to oxidise all the carbon and hydrogen it contains, so a TNT explosion is accompanied by a black cloud of carbon.
Ammonium nitrate is an oxygen-rich explosive, producing more oxygen than it needs, and thus giving a white smoke rather than the black clouds associated with TNT. Organic nitro compounds are widely used in explosives for a combination of reasons. The kind of organic compounds found in natural gas or petrol make good fuels, as the formation of oxygen-hydrogen bonds and carbon-oxygen double bonds releases a lot of energy and a good deal of hot gas, creating the kind of explosive forces than can drive an engine for example.
When they are exploded, nitro-compounds like TNT also produce nitrogen gas, forming very strong nitrogen-nitrogen triple bonds and releasing even more energy. The oxygen content of the nitro compunds also makes the molecules self-oxidising, and the very short distance between the oxygens and the carbon and hydrogen atoms they are combining with contributes to the speed of the reaction.
As well as being destructive, TNT is also very toxic. In the United States alone, over 17, cases of TNT poisoning were reported during the first world war, causing around deaths of munitions workers due to liver damage and anaemia. By the second world war, safety procedures were tightened up. Cleaning up TNT-contaminated soil around factories or places where TNT has been used has become an important environmental issue and scientists are studying plant systems that can sequester and detoxify TNT.
Alfred Nobel worked hard to improve nitroglycerine as an explosive that could be used in blasting rock and in mining. He made one of his most important discoveries when he found that by mixing nitroglycerine, an oily fluid, with kieselguhr , the mixture could be turned into a paste.
This material could be kneaded and shaped into rods suitable for insertion into drilling holes. He called his paste dynamite and went on to develop a blasting cap which could be used to detonate dynamite under controlled conditions.
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