2.4- dinitrotoluene, chemical structures

To explore the capability of OFRR-based pGC in explosive detection, 2,4-dinitrotoluene (DNT) is chosen as a model system, due to its chemical structure... 

The safety limit of temperature depends on the chemical structure of the compound being nitrated. For exMnple, in the nitration of dinitrotoluene to trinitrotoluene or of phenol to picric acid, temperatures neM 120°C Mid over are considered dangerous. In the nitration of dimethylaniline to tetiyl, a temperature higher than 80°C must be considered dangerous. Esterification with nitric acid should be carried out at a temperature close to room temperature or lower. 

Chemicae Structure The chemical structures of the most prevalent and toxicologically important dinitrotoluenes, 2,4-DNT and 2,6-DNT, are shown below... 

Table 7.2 shows how frequently various nitroaromaticss and nitramines occur at explosives-contaminated sites with which die U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) and the Missouri River Division (MRD) have been involved. TNT is the most common contaminant, occurring in approximately 80% of the soil samples found to be contaminated with explosives. Trinitrobenzene (TNB), which is a photochemical decomposition product of TNT, was found in between 40 and 50% of these soils. Dinitrobenzene (DNB), 2,4-dinitrotoluene (2,4-DNT), and 2,6-DNT, which are impurities in production-grade TNT, were found in less than 40% of the soils. Figure 7.2 shows the chemical structures of common explosive contaminants. 

Figure 3. Chemical structure of nitroglycerine (NG), dinitrotoluene (DNT), trinitrotoluene (TNT), pentanerythritoltetranitrate (PETN), cyclotrimethylenetrinitramine (RDX), and trinitrophenyl-n-methylnitramine (Tetryl). Open structures (two on left) are more likely to decompose compared with closed aromatic ring structures.

These studies indicate 1) fermentable fiber increases the total number of viable anaerobic bacteria in the cecum, but not the stomach or small intestine of rats 2) the microfloral capacity for hydrolysis of glucuronide conjugates, for nitroreduction, and for azoreduction is elevated in fermentable fiber-fed rats 3) this increased capacity for microfloral metabolism of nitrobenzene and dinitrotoluene is correlated with an elevation in the toxicity of these nitroaromatics 4) the role fiber plays in the modulation of chemical toxicity is a function of the fiber-type and the structure of the toxicant. 

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