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Reducing hydrogen

High purity 75% ferrosihcon containing low aluminum and calcium can be used in continuously cast heats where nozzle blockage is a problem. In iron melting, this ahoy is desirable to minimize buildup on refractory faces in the furnace or on stopper rods or nozzles. Low aluminum ferroshicons can also help reduce hydrogen pin holes in castings poured in green-sand molds. [Pg.540]

Lyondell and Sun Oil Co. are the main producers of benzene by disproportionation. Eiaa Oil Co. of Texas has developed the Eiaa T2BX process for toluene disproportionation usiag a proprietary catalyst. The new catalyst is claimed to reduce hydrogen consumption and is suitable for feeds containing small amounts of moisture (53). A commercial production unit was started up ia the fall of 1985. [Pg.42]

Replacement of some or all of the —CONH— hydrogens by alkyl or alkoxy-alkyl groups to reduce hydrogen bonding which results in softer, lower melting point and even rubber polymers (A-substitution). [Pg.505]

In situations such as the acid pickling of steel or the use of steel pipes to handle sour oil streams, the use of suitable inhibitors can give a significant reduction in hydrogen entry. In this context it is important to emphasise that the efficiency of an inhibitor in reducing hydrogen entry is not the same as its efficiency in reducing corrosion. Thus arsenic and antimony compounds... [Pg.1250]

Encapsulation of Magnesium to Reduce Hydrogen Generation , Naval Ammunition Depot, Crane, Indiana, Report RDTN No 198 (25 Aug 1971), AD-900094L 8) S.V. Peterson, En-... [Pg.143]

Hydrogen is prepared in small amounts in the laboratory by reducing hydrogen ions from a strong acid (such as hydrochloric acid) with a metal that has a negative standard potential, such as zinc ... [Pg.706]

Beryllium does not react with water, even when red hot its protective oxide film survives even at high temperatures. Magnesium reacts with hot water (see Fig. 13.22), and calcium reacts with cold water (Fig. 14.21). The metals reduce hydrogen ions to hydrogen gas, but neither beryllium nor magnesium dissolves in nitric acid, because both become passivated by a film of oxide. [Pg.714]

Due to reduced hydrogen bonding, thiosulfuric acid should be less acidic and have a lower boiling point. [Pg.1014]

Thiols are also important protection against lipid peroxidation. Glutathione (7-Glu-Cys-Gly) is used by several glutathione-dependent enzymes such as free-radical reductase (converts vitamin E radical to vitamin E), glutathione peroxidase (reduces hydrogen peroxide and lipid hydroperoxides to water and to the lipid alcohol, respectively), and others. In addition, the thiol group of many proteins is essential for function. Oxidation of the thiol of calcium ATPases impairs function and leads to increased intracellular calcium. Thiol derivatives such as the ovothiols (l-methyl-4-mercaptohistidines) (Shapiro, 1991) have been explored as therapeutics. [Pg.268]

Pant and Levinger have measured the solvation dynamics of water at the surface of semiconductor nanoparticles [48,49]. In this work, nanoparticulate Zr02 was used as a model for the Ti02 used in dye-sensitized solar photochemical cells. Here, the solvation dynamics for H2O and D2O at the nanoparticle surface are as fast or faster than bulk water motion. This is interpreted as evidence for reduced hydrogen bonding at the particle interface. [Pg.414]

Figure 4 Stabilized bromine antimicrobials are produced by eosinophils, a type of mammalian white blood cell. Bacteria are captured by phagocytosis and contained intracellularly within vesicles called phagosomes. Granules release cationic surfactants, lytic enzymes, and eosinophil peroxidase into the phagosome in a process known as degranulation. Eosinophil peroxidase, an enzyme that is structurally similar to the bromoperoxidases found in seaweed (Figure I), selectively catalyzes oxidation of bromide to hypobromite by reducing hydrogen peroxide to water. The hypobromite immediately reacts with nitrogenous stabilizers such as aminoethanesulfonic acid (taurine) to form more effective and less toxic antimicrobial agents. Figure 4 Stabilized bromine antimicrobials are produced by eosinophils, a type of mammalian white blood cell. Bacteria are captured by phagocytosis and contained intracellularly within vesicles called phagosomes. Granules release cationic surfactants, lytic enzymes, and eosinophil peroxidase into the phagosome in a process known as degranulation. Eosinophil peroxidase, an enzyme that is structurally similar to the bromoperoxidases found in seaweed (Figure I), selectively catalyzes oxidation of bromide to hypobromite by reducing hydrogen peroxide to water. The hypobromite immediately reacts with nitrogenous stabilizers such as aminoethanesulfonic acid (taurine) to form more effective and less toxic antimicrobial agents.
At many plants, fluxes are added to the metal to reduce hydrogen contamination, remove oxides, and eliminate undesirable trace elements. Solid fluxes such as hexachloroethane, aluminum chloride, and anhydrous magnesium chloride may be used, but it is more common to bubble gases such as chlorine, nitrogen, argon, helium, and mixtures of chlorine and inert gases through the molten metal. [Pg.198]


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See also in sourсe #XX -- [ Pg.281 , Pg.292 ]




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