Nitrates, organic inhibitors

Corrosion Inhibitor CS [Nalco]. TMfor a synergistic combination of sodium nitrate, borax, and organic inhibitors, used to prevent corrosion of ferrous and nonferrous metal and alloy surfaces in low-makeup closed cooling and heating systems. 

Tavandashti, NP, Sanjabi, S (2010), Corrosion study of hybrid sol-gel coatings containing boehmite nanoparticles loaded with cerium nitrate corrosion inhibitor . Progress in Organic Coatings, 69, 384-391. 

Sulphates, silicates, carbonates, colloids and certain organic compounds act as inhibitors if evenly distributed, and sodium silicate has been used as such in certain media. Nitrates tend to promote corrosion, especially in acid soil waters, due to cathodic de-polarisation and to the formation of soluble nitrates. Alkaline soils can cause serious corrosion with the formation of alkali plumbites which decompose to give (red) lead monoxide. Organic acids and carbon dioxide from rotting vegetable matter or manure also have a strong corrosive action. This is probably the explanation of phenol corrosion , which is not caused by phenol, but thought to be caused by decomposition of jute or hessian in applied protective layers. ... 

Vasodilators are a group of dtugs, which relax the smooth muscle cells of the blood vessels and lead to an increased local tissue blood flow, a reduced arterial pressure and a reduced central venous pressure. Vasodilators reduce the cardiac pre-load as well as after-load and thereby reduce cardiac work. They are used in a variety of conditions including hypertension, cardiac failure and treatment/prevention of angina pectoris. Major groups are Ca2+-channel blockers (e.g. dihydropyridines), NO-donators (e.g. organic nitrates), K+-channel openers (minoxidil), phosphodiesterase inhibitors (e.g. sildenafil), Rho-kinase inhibitors (e.g. Y27632) or substances with unknown mechanism of action (e.g. hydralazine). Inhibitors of the... 

In the days of riveted boilers, concentration of caustic took place through the seepage or leakage of BW into rivet holes or seams. Sodium nitrate was the classic SCC inhibitor and was applied at 20 to 40% of the caustic alkalinity (2P-M). It is still used today in certain older facilities, although alternative organic-based inhibitors are now available. 

This salt is used as an inhibitor for the polymerisation of butadiene. It seems to play its role very well when its concentration is lower than 0.5%. If the concentration is greater than 5%, a black precipitate forms which contains 80% of organic polymer containing nitrate and nitrite groups in the proportions of 2 1. This solid combusts spontaneously at 150 C even when there is no air. 

In their studies of the flavoprotein inhibitor, DPI, Bennett and colleagues [91, 120] found that DPI inhibited GTN-induced accumulation of cGMP to the same extent in aortae from naive and from GTN-tolerant animals. They argued that, if inactivation of flavoproteins is a major cause of tolerance, then there should be less scope for further, DPI-induced inactivation in tolerant animals, compared with naive ones. Their conclusion, accordingly, was that, while flavoproteins may participate in biotransformation of organic nitrates and associated vasodilation, their alteration cannot be the basis for nitrate tolerance. 

Effects of the flavoprotein inhibitor, diphenylene iodonium sulfate, on ex vivo organic nitrate tolerance in the rat. J. Pharmacol. Exp. Ther. 293 (2000), p. 569-577... 

Attack by organisms other than SRB. Ammonia and amines are produced by microbial decomposition of organic matter under both aerobic and anaerobic conditions (ammo-nification). (Stott)5 These compounds are oxidized to nitrite by aerobic bacteria such as Nitrosomonas or Nitrobacter species. Nitrobacter is very efficient at destroying the corrosion-inhibition properties, of nitrate-based corrosion inhibitors by oxidation, unless a biocidal agent is included in the formulation. The release of ammonia at the surfaces of heat-exchanger tubes has a detrimental effect. (Stott)5... 

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