Alkaline oxygenation

Alkaline oxygen scavengers may be used as alternative treatments to some corrosion inhibitors where toxicity restrictions prohibit proprietary blends. 

Sel alcali volatil ammonium carbonate Terre ahsorbante alkaline oxygen compounds, calcium carbonate, etc. 

Table I. Literature Citations of Nitrobenzene, Alkaline Oxygen,...

In the literature cited for wood oxidation only acetic and fumaric acids have been reported for alkaline nitrobenzene only formic, acetic, and oxalic acids for nitric acid glycolic, lactic, and malonic acids have not been previously reported for alkaline oxygen. In addition to these compounds minor peaks have been obtained on various chromatograms these have not yet been identified. 

Of the four compounds—guaiacol, vanillin, syringaldehyde, and acetosyringone—found in the methyl ether fraction of the alkaline oxygen reac-... 

Similarly, the methyl ester fraction of the alkaline oxygen reaction contained the methyl esters of benzoic acid, the di-, tri-, and tetracarboxy-benzenes, and the methyl ether ester of vanillic acid. The methyl ether ester of syringic acid was also found. With regard to other acids reported... 

More compounds have been identified in the neutral oxygen methyl ester fraction, shown in Figure 9, than in either the alkaline or acidic oxygen reactions. In addition to the products found in the alkaline oxygen reaction, the methyl ether ester of p-hydroxybenzoic acid and the methyl ester of mellitic acid are present. The acidic oxygen methyl ester fraction, also shown in Figure 9, qualitatively resembles the alkaline oxygen reaction. All the acids found in this latter reaction, except benzoic, are found in this fraction. The methyl ether ester of dehydrodivanillic acid or the methyl... 

Figure 8. Chromatograms of methyl ether esters and methyl esters from alkaline nitrobenzene and alkaline oxygen oxidation liquors...

Results of the previously described semiquantitative method of analysis, applied to methyl enters, are reported in Table V. Yields of products eluting before methyl benzoate have not been included in this table since these should be included in the results presented in Table III. Total yield of methyl esters was largest in the neutral oxygen oxidation, slightly lower under alkaline oxygen oxidation, and substantially lower in acidic oxygen, nitric acid, and alkaline nitrobenzene oxidations. The differences in yields may be attributed in a large part to three major peaks phthalate, a component at a relative retention time of 0.490, and benzoate. 

During an alkaline oxygen stage the formation of keto structures by oxidation of ketols is postulated, finally leading to acids. Sodium permanganate treatments yield a moderate increase in both, carbonyls and carboxyl groups at short reaction times [20]. 

Manganese, because of its relative stability in seawater (Ehrlich, 1990), is a potentially important energy source associated with hydrothermal vents. The high flux of reduced Mn2+ to neutral to slightly alkaline oxygenated waters and the relatively low amount of dissolved organic carbon, make hydrothermal... 

Slanac DA, Lie A, Paulson JA, Stevenson KJ, Johnston KP (2012) Bifunctional catalysts for alkaline oxygen reduction reaction via promotion of ligand and ensemble effects at Ag/MnOx nanodomains. J Phys Chem C 116(20) 11032-11039... 

Maintenance of vitamin activity in the supplement is affected by temperature, humidity, addity/ alkalinity, oxygen, ultraviolet hght, the presence of some trace minerals (dietary supplements are usually combinations of vitamins, minerals and trace elements), physical factors such as hammer milling and the length of time the supplement is stored. For example, choline chloride can destroy other vitamins during storage. 

Once the bacterial growth and insulin production characteristics have been identified, scientists increase the scale of the bioprocess. They use or build small bioreactors (1-10 liters) that can monitor temperature, pH (acidity-alkalinity), oxygen concentration, and other process characteristics. The goal of this scale-up is to optimize bacterial growth and insulin production. 

The tartaric acids are formed by the oxidation of hexose sugars and of the keto acids. (See under Nitric acid and Alkaline oxygen oxidations, particularly.) The L-isomer has been recovered from grape residues by concentration on a basic ion-exchange resin (45). 

Alternatively to non-pressurized extraction the application of 0.6 MPa Oj pressure was investigated. These experimental conditions should generate an alkaline oxygen bleaching effect and lower the lignin content in both, the extracted xylan powder and the extraction residue. 

In neutral or slightly alkaline, oxygen-free aqneons systems, corrosion of fairly clean steel occurs at a very low rate at elevated temperatures. This principle is the basis for most boiler water treatment to prevent corrosion, i.e., treatment is designed to provide alkalinity, to remove oxygen, and to prevent scale deposition. Other additives are also nsed to prevent foaming, but these will not be considered here. 

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