פרסומים

A review with 22 refs. The compn. of amino acids in kidney stone matrixes and inhibitory materials from normal urines is discussed. The amino acid factor (FAA) proposed is FAA = (Glutamic acid)/(Aspartic acid + Alanine); its value in fractions of non-potent inhibitory material and in kidney stone matrixes is \textless0.6. In potent portions of the inhibitory material sepd. from healthy people and young animals' urine the value is ≥0.8. The role of enzymes in calcium oxalate stone formation and the exptl. evidence of acidic amino polymers and monomers effect on calcium oxalate crystn. are also discussed. [on SciFinder(R)]

Bromination, chlorination, and hydroxylation of the hydrophobic chains of com. available polyethylene glycol oleyl ether [9004-98-2], polyethylene glycol monooleate [9004-96-0], and polyglycerol esters resulted in surfactants with improved hydrophobic properties and unchanged hydrophilic moieties. The modified surfactants stabilized paraffinic oil in water emulsions. The derivatization of the nonionic surfactants increased their HLB value. The ability of the surfactants to stabilize the emulsions was not due to increased sp. gravities but rather due to the fact that better steric arrangement on the interface was obtained. [on SciFinder(R)]

Bromination of the arom. ring of ethoxylated nonylphenols produced surfactants which were effective emulsifiers for oil-in-water emulsions and which had slightly higher HLB values than their nonbrominated analogs. The bromination increased the sp. gr. to values higher than that of water, allowing formation of oil-in-water emulsions with denser droplets. Initial bromination caused an increase in viscosity while further bromination decreased viscosity. The refractive index increased with increasing oxyethylene chain length and bromination. Crit. micelle concns. for the brominated surfactants were lower than those for the nonbrominated surfactants. Bromination decreased the surface excess concn. values for the compds. [on SciFinder(R)]