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Abstract  

The dilution enthalpies of D-mannitol and D-sorbitol in aqueous sodium chloride solution at various concentrations have been determined by isothermal microcalorimetry at 298.15 K. The homogeneous enthalpic interaction coefficients over a quite large range of concentration of aqueous sodium chloride solutions have been calculated according to the excess enthalpy concept. The results show that enthalpic pairwise interaction coefficients (h 2) of D-mannitol and D-sorbitol are positive in aqueous sodium chloride solution and become more positive with increase of the concentration of sodium chloride. The results are interpreted in terms of the different conformations of the two polyols, solute-solute and solute-solvent interactions involved by solvent effects.

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Abstract  

Glass ampoule breakage during the freeze-drying process was prevented by the addition of sodium chloride to the formulation of lyophilization products of sodium thiopental. In order to clarify the ampoule breakage prevention mechanism, the physicochemical behavior of the freeze-drying process was monitored by simultaneous XRD-DSC measurements and thermal mechanical analysis (TMA). During the freezing process of formulated solution, the smaller heat of fusion of crystallized ice with the addition of sodium chloride was observed in comparison to that without sodium chloride. Although a greater amorphous portion remained, a higher crystal habit of hexagonal ice was reproducibly observed in the XRD patterns with the addition of sodium chloride during the freezing process. In the measurement of TMA, the scattering of the thermal expansion rate of formulated solution was significantly reduced by the addition of sodium chloride. These observations indicated that the addition of sodium chloride minimized the scattering of the thermal expansion rate and might be a cause for the inhibition of glass ampoule breakage during the freeze-drying process.

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Nabil, M., Coudret, A. (1995): Effect of sodium chloride on growth, tissue elasticity and solute adjustment in two Acacia nilotica subspecies. Physiol. Plant. , 93 , 217–224. Coudret A

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Abstract  

A spectrophotometric study is reported of the oxido-reductant reactions with the major coenzymes as NADH, NADPH, NAD+, NADP+ and FAD effected by low dose and by the energy stored in F and hole centres in -irradiated sodium chloride. The G values for the two modes of these redox reactions are compared.

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Abstract  

The enthalpies of dilution of matrine (MAT) in pure water and aqueous sodium chloride solutions were determined by isothermal titration microcalorimetry at 298.15 K, and the corresponding homogeneous enthalpic interaction coefficients were calculated according to the modified McMillan–Mayer model. The values of enthalpic pair-wise interaction coefficients, h 2, are all positive and become more positive with increasing concentration of sodium chloride.

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Abstract  

A spectrophotometric study is reported of the pigment formation from free radicals produced from o-dianisidine dihydrochloride and pyrogallol by the action of -irradiated sodium chloride. The species liberated during dissolution of the -irradiated salt also greatly enhance the rate of catalytic formation of the pigment due to peroxidase enzyme in the presence of hydrogen peroxide. The G values for these systems are compared.

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Abstract  

A new thermochemical closed cycle of sodium chloride for the preparation of chlorine and sodium hydroxide is presented in this paper. The optimum conditions of the main reactions in the cycle were obtained from a series of experimental results. The heat flow of the cycle system was calculated based on the related thermodynamic equations and data. The kinetic study of the heterogeneous reaction in the cycle was carried out by means of a thermogravimetric method. The result shows that the proposed cycle demonstrates an obviously energy-saving advantage over all the other methods of chlorine and sodium hydroxide productions. It may become economically competitive with the current electrolytic method in the future.

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Abstract  

Optical absorption by electrons trapped in natural anionic vacancies in NaCl has been used for the construction of a dosimeter for radiation processing. To meet the demands of electron beam processing, characterised by congestion of isodoses, the active part of the dosimeter, i.e., the microcrystals of NaCl are embedded in a 0.3 mm thick polyethylene film, in which doses from 10 MeV electrons do not exceed ±2% difference in extreme parts of the dosimeter body. The dosimetric film is opaque and the optical density at the wavelength max = 465 nm, i.e., the maximum absorption of the F band, is measured by diffuse reflected light spectrophotometry (DRS). The measurement is performed against the unirradiated film as reference, thus increasing the accuracy, by self-compensation of signals not belonging to the absorption of F-centres. The spectrum obtained in such a way is identical with that of F-centres in irradiated single NaCl crystals. The calibration curve of the height of the band is almost linear versus the dose in the range of several tens of kilograys. As ordinary grades of sodium chloride may be used, the dosimeter developed is cheap and enables to map the irradiation field in objects of complicated geometry.

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3 244 252 Shlosberg, A., Bellaiche, M., Berman, E., Ben David, A., Deeb, N. and Cahaner, A. (1998): Comparative effects of added sodium chloride

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