Liquid nitroglycerine

Liquid nitroglycerine and gelatinous explosives made from it can exhibit two stable velocities of detonation, of approximately 2000 and 8000 m s 1 respectively. The phenomenon is complicated by the occurrence of air bubbles in such explosives and has not yet been completely explained. 

Fortunately, explosives have an activation energy, so it takes some energy to get the reaction started. Usually, what starts the reaction is heat, but it can be a physical shock for especially sensitive explosives like liquid nitroglycerin. 

Accdg to Rinkenbach (Ref 62, p6 45), straight liquid Nitroglycerin (LNG) has been used for many years for "bringing in oil wells after drilling operation. This was done despite many disastrous episodes in transportation and hand-... 

On suitable initiation of a homogeneous liquid explosive, such as liquid nitroglycerine, the pressure, temperature, and density will all increase to form a detonation wave front. This will take place within a time interval of the order of magnitude of 10 12 s. Exothermic chemical reactions for the decomposition of liquid nitroglycerine will take place in the shockwave front. The shockwave will have an approximate thickness of 0.2 mm. Towards the end of the shockwave front the pressure will be about 220 kbar, the temperature will be above 3000 °C and the density of liquid nitroglycerine will be 30% higher than its original value. 

On the basis of the dipole moment values and viscosity measurements of the two forms of nitroglycerine, de Kreuk [20] considered that the difference between the two forms is produced by rotational isomerism. According to this hypothesis the labile and stable forms would correspond to cis- and trans-isomers respectively. In a non-polar solvent the traits form predominates. In a polar solvent the content of the cis form increases and reaches a maximum in liquid nitroglycerine. 

The specific heat of nitroglycerine was determined by Nauckhoff [18] as 0.356 cal/g and that of the crystalline substance (stable form) as 0.315 cal/g. For liquid nitroglycerine Belayev [45] published the value 0.4 cal/g. 

In the earlier experiments of Beckerhinn [79], Hess [70] and Will [80] it was reported that in order to bring about an explosion of solid nitroglycerine a 3-4 times more powerful shock was needed than in the case of liquid nitroglycerine. 

These considerations would suggest that solid nitroglycerine is likely to explode more readily than the liquid nitroglycerine as, indeed, it does, as confirmed experimentally by Gorst and Andreyev [82] and by Hackel [29]. The results of Hackel s investigations are quoted in Table 15. 

Rate of detonation. The rate of explosion of a liquid explosive may vary within wide limits. Thus, according to numerous experiments it has been established that for liquid nitroglycerine the order of the explosion rate is 1000-8000 m/sec. The detonation rate of solid nitroglycerine, on the other side, does not vary in this way. It amounts 8000 m/sec at the maximum density of loading. 

It follows from the data quoted that liquid nitroglycerine explodes with a moderate velocity of the order 1000-2000 m/sec, if the initiation of explosion is insufficiently strong. 

The pipeline (or gutter) includes several bends. Since liquid nitroglycerine has relatively little inclination to detonate it is highly likely that an explosion might be quenched at one of the curves. 

Transport of liquid nitroglycerine from the nitroglycerine factory to another plant is not allowed in Europe. It can be transported only in mixed forms as dynamites or semi-finished mixtures ready to be used for the manufacture of mining explosives or of double base powders. Only in U.S.A. is the transport of nitroglycerine in special trucks allowed. 

To bring about complete detonation, as with liquid nitroglycerine, a rather... 

The combustion of large amounts of the substance can lead to explosion. Liquid nitroglycol is more readily initiated by means of a detonator than liquid nitroglycerine, and explosive combinations containing nitroglycol behave similarly. 

The physical properties of the nitric esters resemble in a general way the physical properties of the alcohols from which they are derived. Thus, methyl and ethyl nitrate, like methyl and ethyl alcohol, are volatile liquids nitroglycerin is a viscous oil, more viscous and less volatile than glycol dinitrate as glycerin is more viscous and less volatile than glycol. Nitrocellulose from... 

Liquid nitroglycerin is still used as an explosive to a limited extent, particularly in the blasting of oil wells, but its principal use is in the manufacture of dynamite and of the propellants, ballistite and cordite. 

Thus, 29 mol of gaseous products with a volume of 650 L at STP (Section 9.3) are produced from just 4 mol of liquid nitroglycerin. 

Nobel found that liquid nitroglycerine when absorbed in kieselguhr could be packed conveniently and safely into paper cartridges. Discovery of Guhrdynamite. 

The limitations of black powder as a blasting explosive were apparent for difficult mining and tunneling operations. More efficient explosives were required. Liquid nitroglycerine [C3H503(N02)s], 1, that was discovered by the Italian Professor Sobrero, was later studied and manufactured by the Swedish inventor, Immanuel Nobel in 1863. The major problem that the Nobel family faced was the transportation of liquid nitroglycerine that causes loss of life and property. The destruction of the Nobel factory in 1864 was one of many accidents caused by the explosion of nitroglycerine. 

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