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Abstract  

The concentration of thirty-four elements in twelve coffee brands has been measured using instrumental neutron activation analysis. The samples investigated included four brands of commercially available ground coffee and eight brands of soluble/instant coffee. The elements measured were Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Gd, Hf, K, La, Lu, Mg, Mn, Na, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Tm, U, V, Yb and Zn. Twenty four elements were found to be below the detection limit in one or more samples. These elements were Ce, Cr, Fe, V, As, Eu, Ba, Dy, Gd, Hf, La, Lu, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Yb, Tm, and U.

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Loar, R. E., Schilling, M. W. and Corzo, A. (2009): Organoleptic and compositional effects of feeding distillers dried grains with solubles on broiler meat. Poult. Sci. 88(Suppl. 1) , 149 (Abstract M53). Corzo

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sulfonated phosphines or analogue complexes [ 7 – 11 ]. At present, our research is directed toward the synthesis of the sodium salt of sulfonated pyridine [ 12 , 13 ] as a water-soluble ligand with different metallic centers. The principal goal in this work

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Abstract  

The solubility and solubility product of erbium trifluoride in aqueous solution were measured using three different techniques. The more acceptable radiometric values for the solubility and solubility product are 1.98×10–5M and 3.5×10–18, respectively. The values for the thermodynamic functions, H 298 o , G 298 o and S 298 o for the dissolution of ErF3 and the stability constant for ErF2+ have also been measured.

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Interactions between AuCl4 and CTA+ ions in water

Enthalpies for the formation of the precipitate

Journal of Thermal Analysis and Calorimetry
Authors: Makoto Takezaki, Hiroyuki Aoki, Michiko Kodama, and Toshihiro Tominaga

Abstract  

The solubility of hexadecyltrimethylammonium tetrachloroaurate (CTA·AuCl4) in water was measured at different temperatures of 288.2, 293.2, 298.2, 303.2, and 308.2 K. The enthalpy change associated with the formation of the CTA·AuCl4 precipitate was estimated on the basis of the van’t Hoff equation and was found to be −42.5 ± 2.8 kJ mol−1 at 298.2 K. The calorimetric enthalpy change for the CTA·AuCl4 precipitate formation was directly determined by isothermal titration calorimetry performed at 298.2 K and was found to agree well with that estimated from the van’t Hoff equation.

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Abstract  

Cadmium sulfide particles were prepared by precipitation from acid solution. A radiotracer technique with109Cd was applied to measure the solubility of cadmium sulfide at various pH's. Filtration, centrifugation, ultracentrifugation, and dialysis were used to separate the particles from the solution. Only the last two techniques proved to be successful. The solubility of cadmium sulfide in water (pH=7) is found to be: 7.9·10–5 mol·l–1 in contrast with the literature value of 9.0·10–6 mol·l–1. At low pH (1–4), the solubility agrees fairly well with the solubility calculated on the basis of generally accepted values for the solubility product and for the various complex formation constants, while at high pH (4–14) the solubility is higher than expected.

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Abstract  

Speciation and solubility of neptunium were studied using paper electrophoresis, ion exchange and ultrafiltration. Among these methods, the paper electrophoresis was found to be suitable for measuring speciation and solubility of neptunium of low concentration, if chemical species had opposite charge each other or dissolved species had a charge. Using paper electrophoresis, hydrolysis constants of NpO2OH0 and NpO 2 (OH) 2 and solubility product of NpO2 were obtained and ionic-strength dependence of speciation was observed.

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Abstract  

This work describes the development of a fully automatic apparatus to perform crystallization studies and metastable zone width (MSW) determinations using the polythermal method. Heating and cooling ramps, and isothermal steps can be carried out, while continuously monitoring the mixture inside the crystallization vessel, with temperature and turbidity sensors. These allow the onsets of crystallization or of complete dissolution of the solute to be detected. Programmed dilutions of the mixture under study can also be automatically performed, so that different concentrations can be studied in a given experiment. The apparatus was tested by using the ammonium chloride–water system. The results indicated that it is capable of reproducing the equilibrium solubilities of ammonium chloride in water, independently determined by the residue mass method, with an average deviation of 0.6 K. The obtained MSW and the kinetic parameters for the crystallization process showed deviations from the literature data, which are typical of these studies when nucleation is not induced by the addition of crystalline seeds.

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Abstract  

A radiotracer method to measure the solubility of thallium crown ether complexes is reported. Tl-204 is used as the radiotracer. The method is capable of a precision of 1% or better. The solubilities of 18-crown-6-bis-/thallium-o-nitrophenoxide/ in acetonitrile, benzene, chloroform and DMF were measured.

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Abstract  

The solubility, solubility product and the thermodynamic functions for the CeF3–H2O system have been measured using the radiometric, conductometric and potentiometric techniques. The radiometric values for the solubility and solubility product, the lowest and more acceptable for reasons cited in previous papers, are 3.14·10–5 M and 2.17·10–17 respectively. The enthalpy change measured by the conductometric method is almost twice as that obtained by potentiometric method due to abnormal conductances registered at higher temperatures. The average values for Ho and Go and So at 298 K are 53.0±17.4, 91.7±4.0 and –129.7±58.2 KJ·mol–1 respectively. The positive values for Ho and Go and the negative value for So are indicative of the low solubility of this salt in water. The stability constants for the mono- and difluoride complexes of Ce(III) have been determined potentiometrically using unsaturated solution mixtures of Ce(III) and F. These values for CeF+ and CeF 2 + are 997±98 and (1.03±0.44)·105, respectively. Studies on pH dependence of the solubility shows that the solubility reaches a minimum value at a pH of about 3.2.

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