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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Molecular mechanisms governing alkali metal ion uptake from aqueous solution in MOF-808 are studiedviafree-energy calculations and enhanced sampling simulations, revealing the subtle interplay between hydration structure and confinement effects.
Tabulated activity coefficients of electrolytes in aqueous solutions from freezing point to boiling point of solvent
Here, a continuum aggregation model is proposed to account for specific ion effects, enabling accurate phase diagrams calculations for the micellar, cylindrical and lamellar aggregates of sodium/potassium carboxylate surfactants in aqueous solution across a range of temperatures. Three groups of concentrations at distinctive temperatures are fitted to build empirical temperature dependence given the limited availability of relevant experimental measurements. The specific ion effects are manifested in the aggregates' surface tension as well as in the distributions of counter-ions' concentrations in the vicinity of the aggregates. The aggregates' geometric sizes are well-reproduced. The differential evolution algorithm is applied to address boundary conditions of the electrostatic potential, aggregate size optimization as well as the equilibrium of monomers transferring between the aggregate and aqueous region.
Thermal reaction kinetics of pyrolytic products of proline, leucine, arginine and lysine in aqueous solution
Aluminum concentration effects on stress corrosion cracking of titanium alloys at ambient temperatures in aqueous solutions of salt
On the basis of measurements of the velocity of ultrasounds in aqueous solutions of some alkaline-earth chlorides (MgCl2, CaCl2, BaCl2) the concentration and temperature dependences of the internal pressure were determined. Using these results, as well as surface tension measurements, the mean diameters of the molecular species as a function of concentration and temperature, were determined.
Biochemical stabilization of aqueous solutions of urine by unsaturated flow through columns of sand ripened with settled municipal sewage
Stress corrosion cracking of titanium alloys at ambient temperature in aqueous solution
A study has been made of the properties of triglycine sulfate (TGS) aqueous solution relevant to its use for single crystal growth. Measurements of the solubility, index of refraction, density, viscosity, diffusivity, and optical dispersion are presented and discussed. A knowledge of these properties is of importance for controlling and modeling the growth process and for obtaining high quality single crystals.
The separation and recovery of precious metals from secondary resources is an extremely important and challenging task. Herein, a novel sorbent is successfully prepared by chemical grafting and utilized for the extraction and separation of Pd(II) ions from aqueous solutions. Various characterization techniques, including Fourier transform infrared spectroscopy, scanning electron microscopy, Brunauer–Emmett–Teller, X-ray photoelectron spectroscopy, and element analysis, are employed to study the structure, morphology, porous nature, and chemical composition of the as-prepared SiO{sub 2}@GO-SH nanocomposites. The adsorption of Pd(II) ions on the SiO{sub 2}@GO-SH can be described by the pseudo-second-order model and Langmuir isotherm model. The adsorption equilibrium has been attained within 90 min and the maximum adsorption capacity of 423.2 mg g{sup −1} was attained at pH 3.5 and T = 308 K. The results reveal that SiO{sub 2}@GO-SH exhibits an excellent adsorption performance towards Pd(II) ions. In addition, we have proposed the adsorption mechanism for Pd(II) ions on the SiO{sub 2}@GO-SH surface. The adsorption of Pd(II) in SiO{sub 2}@GO-SH is a chemisorption process, where partial adsorbed Pd(II) ions are reduced to Pd(0) by functional groups (-SH) in the SiO{sub 2}@GO-SH. The results indicate that SiO{sub 2}@GO-SH can serve as a promising sorbent for the efficient separation and recovery of palladium from the palladium-containing secondary resources.
Stress corrosion cracking of titanium alloys at ambient temperature in aqueous solutions
Stress corrosion cracking of titanium alloys at ambient temperature in aqueous solutions
Methanol stress corrosion cracking of Ti-Al-V foil inhibited by pretreatment in aqueous solutions of electrolytes, discussing colloidal character of microcrystallites
Effect of microstructure on stress corrossion cracking of titanium alloys in aqueous solutions at ambient temperatures
Nonradiative transfer of excitation energy between mixed trinuclear complexes of Tb and Eu ions with lactose in aqueous solution
Aluminum concentration effects on stress corrosion cracking of titanium alloys in aqueous solutions
Tin/II/ and Tin/IV/ reactions studied in aqueous acidic solutions using spectrophotometric and ion exchange methods
Methods for removing an oxyanion from an aqueous source containing said oxyanion, comprising contacting said aqueous source with an aqueous-insoluble hydrophobic solution containing an oxyanion extractant compound dissolved in an aqueous-insoluble hydrophobic solvent to result in formation of an oxyanion salt of said extractant compound and extraction of said oxyanion salt into said aqueous-insoluble hydrophobic solution, wherein said extraction results in an extraction affinity (D) of said oxyanion of at least 1, wherein D is the concentration ratio of said oxyanion in the organic phase divided by the concentration of said oxyanion in the aqueous phase; wherein said extractant compound has the following composition: wherein at least one of R1-R10 is or contains a hydrocarbon (R) group containing at least 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon atoms.