Do you know about the different kinds of nitro-explosives?
There are many kinds of explosives which are differentiated on the basis of their explosive charge. Explosive charge is a measured quantity of explosive material. Let us begin with the kinds of nitro-explosives such as trinitrophenol (TNP), trinitrotoluene (TNT), dinitrotoluene (DNT) which are very closely related explosive compounds. Except for these, there are  RDX, PETN, HMX: Very powerful explosives which can be used pure or in plastic explosives.

Nitro-Explosive or Nitroglycerin was the first practical explosive produced that was stronger than black powder. It was first synthesized by the Italian chemist Ascanio Sobrero in 1847 who strongly warned people against using it as an explosive.
It was later adopted as a commercially useful explosive by Alfred Nobel.

However, lax check,detection and security measures on such explosives has led to a lot of incidences, one of which is as follows:

Auburn, California, April 21, 1866. On Monday, in San Francisco, an explosion took place in the storeroom back of Wells, Fargo & Co.’s building, adjoining California Street, which demolished everything within a circuit of 40 or 50 feet

In today’s time, rapid and selective detection of explosives has become one of the most pressing issues concerning homeland security. Tons of explosives are found in many unexploded landmines worldwide. For more information about nitro-explosives and incidences, please visit: http://www.annualreviews.org/doi/full/10.1146/annurev.physchem.49.1.203

The detection of explosives and their associated compounds for security screening, demining, detection of unexploded ordnance, and pollution monitoring is an active area of research. A wide variety of detection methods and an even wider range of physical chemistry issues are involved in this very challenging area.

Hence, California based ELECTRONIC SENSOR TECHNOLOGY Inc. presents…..zNose®!

An electronic nose for ultra-fast gas chromatography.

zNose® is the ideal vapor force-protection tool because it is able to speciate. Even quantifies the chemistry of any vapor with picogram sensitivity and its universal solid-state detector is not ionic and does not require a radioactive ionization element.

Because of its universality zNose® is able to detect and identify virtually any vapor threat including those from explosives, bioterrorism and bio-chemical threats over the range C6 to C30. For more about our homeland security solutions, please visit: https://www.estcal.com/resource/technical-paper-detecting-nitro-explosives-znoser

Retention time libraries allow the use of simple alkane calibration standards instead of hazardous chemicals or explosive standards.

zNose® produced completely speciated chromatograms of DNT, TNT, and TNP using a 5-mL sample of headspace vapors. zNose® demonstrated picogram sensitivity to volatile organics above C16 and the minimum detection limit was approximately 1 picogram.  Higher sensitivity well into the part per trillion range could easily be achieved by increasing the sample time to 60 seconds (30 mL air sample

Tons of explosives are found in many unexploded land mines worldwide. Nitro-aromatics such as 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (2,4-DNT), and 2,4,6-trinitrophenol (TNP) are common ingredients of industrial explosives which have contaminated soil and groundwater at large. Hence, the detection of nitro-aromatics present in soil and groundwater is very crucial for environmental monitoring near ordnance bases. Trinitrotoluene (TNT), Trinitrophenol (TNP or picric acid), and Dinitrotoluene (DNT) are all nearly related chemical compounds with different vapor pressures and volatility, which can be investigated by headspace analysis and direct injection using zNose®.