Nitrogen cycle acidic solution

Nicholson and Pizzarello.35"40 Collins and Schiffrin s Lu(Pc)2 was initially studied as a film immersed in aqueous electrolyte, but hydroxide ion from water causes gradual film destruction, attacking nitrogens of the Pc ring.33 Acidic solution allows a greater number of stable write-erase cycles, up to 5 x 106 cycles in sulfuric acid 33 Lu(Pc)2 films in ethylene glycol solution were found to be more stable 34... 

For the quantitative determination of Krebs cycle acids, Horning et al. [160] recommended methoxime-TMS esters. A 10-mg amount of methoxylammonium chloride is added to a solution of 1 mg of a keto acid (or a mixture of acids) in 0.5 ml of pyridine. After standing for 2-3 h, pyridine is removed with a stream of nitrogen and 0.2 ml of BSTFA is added to the residue containing methoxime and unreacted methoxylammonium chloride. After standing for 1—2 h at room temperature, 0.5—1.0 /al of the solution is taken directly for GC analysis. 

Ammonia is found in the environment as the result of natural and industrial processes. It is released into the environment by the breakdown of organic wastes, and it is a constituent of the soil, the atmosphere, and bodies of water. Ammonia is also a key intermediate in the nitrogen cycle and is a product of amino acid metabolism (WHO 1986). Anhydrous ammonia is used in the production of nitric acid, explosives, synthetic fibers, and fertilizers (Budavari 1989). It is used as a refrigerant as a corrosion inhibitor in the purification of water supplies in steel production as a catalyst for polymers as a preservative for latex and in the production of nitrocellulose, urea formaldehyde, sulfite cooking liquors, and nitroparaffins (ACGIH 1991 Lewis 1993). Ammonium hydroxide (10-35% ammonia) is a major constituent of many cleaning solutions. Ammonia... 

In order to study only adsorbates on the electrode surface, the adsorption of CO was conducted in such a way that during potential cycling between —0.20 and 0.05 V (SCE) in sulphuric acid solution CO gas of high purity was introduced into the IR cell, and after the adsorption of CO on the electrode surface has reached saturation, the solution CO species were removed by bubbling the solution with nitrogen gas of... 

The polyamide-acid solution obtained was cast as a film (ca.. 25 mm thick) onto a glass plate and dried for 12 hours at 80°C under vacuum (30 min). The resulting film was subjected to the following cure cycle under nitrogen on a hot plate monitored with a surface thermometer to effect imidization 100°C (2 hours), 150°C (2 hours), 200°C (1.5 hours) and 300°C (1 hour). High Tg films (Tg > 300°C) were optionally cured for an additional 0.5 hours at a temperature of 480°C in an inert atmosphere oven to ensure imidization and removal of volatiles. 

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