theluckycountry wrote:Scientists were baffled, couldn't explain it, until some bright spark pointed out that ocean temps had risen slightly.
It was easy to miss I suppose given that water has a high specific heat capacity and can absorb or release a lot of heat without changing its temperature much.
Indeed.
Energy contained in 1 Mt of TNT, eg. in approximately 80 Hiroshima sized nukes will rise temperature of 1 km3 of water by 1*C - with accuracy better than 0.1% of error.
It is funny coincidence but tell a lot about rather large thermal capacity of water.
...And those explosions didn't stop Alfred? No, but the Stockholm authorities nearly did; they banned the Nobels from making explosives within the city limits, so production was moved to a barge in a lake.
Being a chemist I had always troubles with nuisance safety officials in industry in the UK where I was working.
There was also a habit to appoint these officials from most stupid staff not really good for doing anything else than hinder activities of others.
Following safety procedures was often making entire R & D experiment
less safe because loads of time was spent to fill repetitive and yet meaningless documentation and then job still had to be done, often in lousy fashion due to limited time left.
This was one of more significant reasons why I have left industry - not to contribute any more to spreading stupidity and decadence - and now run tourism business.
OTOH it is not a good idea to make large quantities of explosives in the middle of city.
Why is nitroglycerine explosive? Apart from its instability, when nitroglycerine is detonated, a lot of gas is formed within microseconds in a very exothermic reaction, generating a pressure up to 275 000 atmospheres:- C3H5N3O9 (liq) ---> N2 (gas) + H2O (gas) + CO2 (gas) + O2 (gas)
Burning 1 kg of coal is far MORE exothermic (but slower process) than detonating 1 kg of nitroglycerine.
Nitroglycerine is still about on par with RDX and above PETN in terms of output but military prefers these due to higher stability.
but it is still quite stable to mechanical shock as long as purified from dissolved acids used in manufacturing.
Though perhaps the strongest chemical high explosive now known is a cryogenic mixture (slurry) of solid acetylene suspended in liquid oxygen.
Pressures in excess of 1 million atmospheres can result.
Compared with it nitroglycerine is more like a dud.
The energy produced by the first few decomposing molecules creates a pressure gradient that detonates more of the nitroglycerine, causing a shockwave resulting in essentially instantaneous decomposition of the whole explosive charge.
Speed of detonation of nitroglycerine is in range of 8 km/s - about the same as first cosmic speed.
275,000 atmospheres, in an eyeblink, that's more than enough to compress solid matter, to allow sub-critical masses of Plutonium to fission. Ahhhh, science. It's beautiful isn't it. Even if it is ultimately in the hands of politicians, psychotics, and shysters.
It is more complicated with Plutonium which is one of most challenging metals to work with from point of view of metalurgist.
It has several allotropic forms, most relevant are delta and alpha forms, the latter of about 25% higher density than the former.
Delta form is metastable in normal conditions - so it would convert into alpha upon standing and nuke core would fall apart into powder upon storage, very much like old Tin pot stored in the cold (what as per some views have contributed to demise of Antarctic Scott expedition in 1906 where Tin soldered fuel tanks fallen apart - Amundsen's dogs have proven to be a superior technology at that time). Fortunately US military have found that small addition of Gallium can stabilize delta form of Pu in resulting alloy, but nevertheless it will convert nearly instantaneously into alpha once subjected to over 2000 at of pressure - well within range of chemical explosives.
An interesting observation is that a detonating core of A-bomb in its central few cc of volume has higher energy density than the same volume of detonating supernova core - and may be at the time of business proceeding the hottest MACROSCOPIC object in entire Universe with an exception of events going on in immediate vicinity of event horizons and below them.