Nitrogen content, distribution

Mixed with additives, urea is used in soHd fertilizers of various formulations, eg, urea—ammonium phosphate (UAP), urea—ammonium sulfate (UAS), and urea—phosphate (urea + phosphoric acid). Concentrated solutions of urea and ammonium nitrate (UAN) solutions (80—85 wt%) have a high nitrogen content but low crystallization point, suitable for easy transportation, pipeline distribution, and direct spray appHcation. 

The nitrogen content of granular urea—formaldehyde reaction products typicahy ranges from 35 to 42% depending on the methylene urea polymer distribution. 

The nature of the nitrocellulose used is of particular importance in explosives if freedom from exudation of free nitroglycerine during storage is to be avoided. Nitroglycerine is only a poor solvent for nitrocellulose and stability of the gel depends on continuous formation and breakdown of gelled structures. The distribution of nitrogen content and viscosity, even in the individual fibres of the nitrocellulose, is therefore of paramount importance. 

Taking into account both their own X-ray investigations and those of other workers, Meyer and Mark [17] came to the conclusion that indistinct pictures of cellulose nitrates having a lower nitrogen content than cellulose trinitrate and hence containing free hydroxyl groups, occur due to the statistically irregular distribution... 

In general these substances are widely distributed in the acid distillates but appear to increase in number at two stratigraphic levels (1) in the middle Silurian McKenzie Limestone and (2) in the middle Devonian shales. Furthermore, possible two- and three-ring aromatic or heteroaromatic structures show similar increases. There is also a rough correlation with the Kjeldahl nitrogen content of the samples (Table VI). 

Supercritical Hydrotreatment of SCE Shale Oil. SCE shale oil was hydrotreated at high severity because of its high nitrogen content (Table i) and extremely high viscosity. The experimental results are shown in Table III. Based on the shale oil fed, the product distribution is the following 12 gases, 52 boiling less than 300°F (calculated by difference) and 36 in the heavy... 

The evolution of fuel nitrogen is not a function of total nitrogen content of a fuel only, but is strongly dependent upon the distribution of nitrogenous compounds in the fuel. The rate of fuel nitrogen evolution is not completely determined by the composition of the fuel, but may be influenced by the rate of vaporization, which is determined by droplet size and ambient temperature. 

Figure 4 shows the differential weight distribution of the nitrogen content Nc, g(Nc), for two CN samples, as estimated by two TLC techniques 13). The full lines are obtained by open TLC with nitromethane-methanol (20/80, v/v), and the broken lines by VP-TLC with acetone-methanol-chloroform (10/10/5, v/v/v). The agreement between the g(Nc) curves evaluated by both methods is fair, considering the possibility of large experimental uncertainty. 

Note Accumulated nitrogen is distributed between following items surface runoff groundwater leakage, and increasing N content in crops, mainly vegetables. 

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