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Phosphate Compounds (phosphate + compound)
Selected AbstractsConversion of Tetranary Borate Glasses to Phosphate Compounds in Aqueous Phosphate SolutionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2008Wenhai Huang In our earlier work, it was found that particles of a ternary alkali-borate glass, containing either CaO or BaO, converted completely to a crystalline phosphate of calcium or barium when reacted in an aqueous phosphate solution at 37°C. The present work is an extension of our earlier work to investigate the conversion of tetranary borate glass with the composition 10Li2O·10CaO·10(AeO or T2O3)·60B2O3 (weight percent), where Ae is the alkai-earth metal Mg or Ba, and T is the transition metal La, Sm, or Dy. In the experiments, particles of each glass (150,300 ,m) were reacted in 0.25M K2HPO4 solution with a starting pH of ,9.0 at 37°C. Weight loss and pH measurements indicated that the reaction was complete after 30,50 h, yielding an amorphous product. X-ray fluorescence showed that the as-formed product consisted of a calcium phosphate phase that contained the alkali-earth metal or transition metal present in the starting glass. Heating the as-formed material for 8 h at 600°,700°C produced a mixture of two crystalline phosphates: calcium phosphate and an alkali-earth or transition metal phosphate. The kinetics and mechanism of converting tetranary borate glass to phosphate materials are discussed and compared with data from earlier work for the conversion of ternary borate glass. [source] Preparation and characterization of silver containing chitosan fibersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2007Yimin Qin Abstract Silver containing chitosan fibers were prepared by blending fine particles of a silver sodium hydrogen zirconium phosphate compound into the spinning solution. It was possible to distribute the silver containing particles in the chitosan fiber because of the high viscosity of the spinning solution and the small diameter of the particles. Because the silver ions are imbedded inside the sodium hydrogen zirconium phosphate complex, the chitosan fibers remain white in color without being oxidized by the silver ions. The release of silver ions from the silver containing chitosan fibers were studied by placing the fibers in contact with distilled water, solution A, and aqueous protein solutions. Results showed that the release of silver ions was low in water, while in solution A and protein solutions, the silver ions are activated through ion exchange and chelation. The silver ions can significantly enhance the antimicrobial properties of the chitosan fibers. Experimental results showed that when placed in contact with the silver containing chitosan fibers, the reduction in bacteria count can be more than 98%. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3622,3627, 2007 [source] 31Phosphorus magnetic resonance spectroscopy study of tissue specific changes in high energy phosphates before and after sertraline treatment of geriatric depressionINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2009Brent P. Forester Abstract Introduction We investigated tissue specific differences in markers of energy metabolism, including high energy phosphate compounds (beta and total NTP, PCr) and pH, in older adults with depression compared with healthy controls, before and after a 12-week treatment trial of sertraline. Methods Thirteen older adults, age ,55, with Major Depressive Disorder (HAMD17 score of ,18) were recruited along with ten age-matched controls. The depression subjects had a pre- and post-treatment 4T 31P-MRS scan using a three-dimensional chemical shift imaging sequence. The extracted brain images were segmented into white matter (WM), gray matter (GM) and CSF. A linear mixed effects model analyzed the effects of pre-treatment and post-treatment depression on phosphorus metabolite concentration estimates (including calculated pH and Mg++). Results Total tissue beta-NTP (,8%, t(18.66),=,3.50; p,=,0.0024) and total tissue total NTP (,6%, t(17.41),=,2.68; p,=,0.0156) were lower in subjects with geriatric depression compared with healthy controls. Total tissue levels of total-NTP changed significantly with treatment (,2%, t(14.84),=,,2.47; p,=,0.0259). Total NTP was reduced in the WM, but not the GM, in the pre-treatment depression group (t(51.65),=,4.02; p,=,0.0002). Intracellular pH was higher in the GM of subjects with pre-treatment depression (t(1133.84),=,,2.10; p,=,0.0353) and decreased to approximate control levels after treatment (t(648.86),=,,2.53; p,=,0.0115). Discussion These findings demonstrate bioenergetic changes including tissue specific differences in 31P-MRS metabolites in geriatric depression. Decreased white matter total NTP may reflect alterations in white matter function. Copyright © 2009 John Wiley & Sons, Ltd. [source] Evaluation of Garam Masala Spices and Phosphates as Antioxidants in Cooked Ground BeefJOURNAL OF FOOD SCIENCE, Issue 5 2006Mihir N. Vasavada ABSTRACT:, This study determined antioxidant effects and sensory attributes of individual ingredients (black pepper, caraway, cardamom, chili powder, cinnamon, cloves, coriander, cumin, fennel, ginger, nutmeg, salt, star anise) of an Indian spice blend (garam masala) in cooked ground beef. Thiobarbituric acid (TBA) values were measured as an indicator of rancidity for cooked samples on 1-, 8-, or 15-d refrigerated storage. Cooked samples were evaluated by a trained panel (n= 13) for the intensity of rancid odor/flavor, beef flavor, and spice flavor and correlated with TBA values of same day samples. We also investigated possible additive effects between spice antioxidants and iron binding (type II) antioxidants on lipid oxidation by measuring TBA values. All spices had antioxidant effects on cooked ground beef, compared to controls. Among spices, cloves were the most effective in controlling lipid oxidation, with TBA values of 0.75, after 15-d refrigerated storage. All spices at their recommended levels lowered rancid odor and flavor in cooked ground beef, compared to controls. As expected, most spices also imparted distinctive flavors to cooked ground beef. There was a positive correlation (0.77) between TBA values on 15-d refrigerated storage and rancid odor/flavor. Type II antioxidants (iron-binding phosphate compounds) were more effective than individual type I antioxidants (spices and butylated hydroxytoluene; BHT) for maintenance of low TBA values in cooked ground beef during storage. Additive effects were observed with rosemary + milk mineral or sodium tripolyphosphate (STP) compared to rosemary alone. [source] Identification of human calculi with time-of-flight secondary ion mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 2 2010C. Amjad A. Ghumman Time-of-flight secondary ion mass spectrometry was used to study four human calculi and to compare the results with those from twelve commercially available urinary calculi minerals including three organic compounds (L-cystine, uric acid and sodium urate). Phase identification of calcium phosphate compounds was carried out by considering the relative ion abundances of [Ca2O]+ and [CaPO2]+. Deprotonated [M,H], and protonated [M+H]+ uric acid were detected and used for component recognition in pure uric acid and in the mixed samples of struvite, calcium oxalate and uric acid. Iodine related to the medical history of a patient was also detected. Copyright © 2009 John Wiley & Sons, Ltd. 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