NaI In Water Research Articles

Visible-light-induced surfactant-promoted sulfonylation of alkenes and alkynes with sulfonyl chloride by the formation of an EDA-complex with NaI in water at room temperature

We report an efficient visible-light-induced iodosulfonyl reaction of alkenes in water using an EDA complex strategy at room temperature. The addition of a cationic surfactant allows for the easy formation of colored EDA complexes in water.

Correlation Length in Concentrated Electrolytes: Insights from All-Atom Molecular Dynamics Simulations.

We study the correlation length of the charge-charge pair correlations in concentrated electrolyte solutions by means of all-atom, explicit-solvent molecular dynamics simulations. We investigate LiCl and NaI in water, which constitute highly soluble, prototypical salts for experiments, as well as two more complex, molecular electrolyte systems of lithium bis(trifluoromethane)sulfonimide (LiTFSI), a salt commonly employed in electrochemical storage systems, in water, and in an organic solvent mixture of dimethoxyethane and dioxolane. Our simulations support the recent experimental observations as well as theoretical predictions of a nonmonotonic behavior of the correlation length with increasing salt concentration. We observe a Debye-Hückel like regime at low concentration, followed by a minimum reached when d/λD ≃ 1, where λD is the Debye correlation length and d is the effective ionic diameter, and an increasing correlation length with salt concentration in very concentrated electrolytes. As in the experiments, we find that the screening length in the concentrated regime follows a universal scaling law as a function d/λD for all studied salts. However, the scaling exponent is significantly lower than the experimentally measured one and lies in the range of the theoretical predictions based on much simpler electrolyte models.

Comparative Studies on Cotton Seed Germinability with Tetrazolium Viability Test and X-ray Contrast Methods

Seed viability testing provides valuable information for assessing seed lot germinability. However, most testing methods require destruction of seed prior to test. Because the dissected seeds for viability test cannot be used further evaluation, the nondestructively X-ray photography technique that can be applied for the evaluation of seed quality has been developed. In order to know the validity and accuracy of X-ray photography technique in seed evaluation test that conducted to remove the abnormal seed from a seed lot, we have compared the results from tetrazolium viability test, germination test and X-ray contrast method in cotton. Metallic salts treatment increased the efficiency of X-ray photographic method by enhancing the penetration of X-ray in abnormal or damaged seeds rather than normal seeds that have strong and well-organized tissues in seed. Cotton seeds presoaked for 16 hr in distilled water followed by soaking into metallic salt solution (5% NaI in water) for 60 min were easily classified seeds into dead seed and viable seed based on the radiography images obtained by X-ray radiation. We concluded that soft X-ray photography was reliable to find out the various defective characters due to heat and mechanical damage of seeds.

Solubility, Density and Solution Thermodynamics of NaI in Different Pure Solvents and Binary Mixtures

Solubility of NaI in water, methanol, ethanol, propan-2-ol, and also in water + methanol, water + ethanol, and water + propan-2-ol binary mixtures have been experimentally measured using a gravimetric method at temperatures (298.15.303.15, 308.15, and 313.15) K. The combined NIBS (nearly ideal binary solvent)–Redlic–Kister equation is used to fit experimental solubility data at constant temperature. The densities of the saturated solutions are also reported in pure and binary solvent mixtures at temperatures mentioned above. Thermodynamic functions including ΔHsoln0, ΔGsoln0, and ΔSsoln0 of solution of NaI are obtained from the modified van’t Hoff equation. A comparison of the relative contributions by enthalpy (ζH) and entropy (ζTS) is made which indicated that the main contributor to the positive standard molar Gibbs energy of solution of NaI is the entropy for solution of NaI in water + methanol having xC0 < 0.5 and for all other solutions it is enthalpy.

Volumetric Parameters of Interaction of Monosaccharides (D-xylose, D-arabinose, D-glucose, D-galactose) with NaI in Water at 298.15 K

Densities for monosaccharide (D-xylose, D-arabinose, D-glucose, D-galactose)–NaI–water solutions were measured at 298.15 K and were used to calculate the apparent molar volumes of these saccharides and NaI. Infinite dilution apparent molar volumes for the saccharides (VΦ,S∘) in aqueous NaI and those for NaI (VΦ,E∘) in aqueous saccharide solutions and partial molar volumes of the saccharides (VS) and NaI (VE) at each composition have been evaluated, together with the standard transfer volumes of the saccharides (Δtr VS∘) from water to aqueous NaI and those of NaI (ΔtrVE∘) from water to aqueous saccharide solutions. It was shown that the Δ tr VS∘ and ΔtrVE∘ values are positive and increase with increasing co-solute molalities. Volumetric parameters indicating the interactions of NaI with saccharides in water were also obtained and applied to explore the interactions between saccharides and NaI in water. A comparison of the νES value for NaI with those for NaCl and NaBr showed that for a given saccharide, except for glucose, the νES value for NaBr is the largest of three sodium halides (NaCl, NaBr and NaI). These were interpreted in terms of the apparent molar electrostriction volumes (Δ Ve) and the structure interaction model.

Conductivity study of NaCl and NaI solutions in water — 2-butoxyethanol mixtures at 298.15K. The effect of ion pairing on the standard dissolution enthalpies of NaCl and NaI

Abstract The electric conductivity of NaCl and NaI in water — 2-butoxyethanol mixtures was measured at 298.15K and analysed using Fuoss — Justice equation. For the both salts, the limiting molar conductance decreases and the equilibrium constant of ion-pair formation increases along with increase of 2-butoxyethanol content. The standard dissolution enthalpies of NaCl and NaI in water — 2-butoxyethanol mixtures were recalculated taking into account the ion — association process. The electric permittivity for mixtures of water with 2-butoxyethanol was measured over the whole composition range within 288.15 – 308.15K. The Kirkwood correlation factor for investigated mixtures was calculated.

Interactions in aqueous solutions of urea derivatives and NaI at 298.15 K

Enthalpies of dissolution of NaI in aqueous solutions of urea, monomethylurea, monoethylurea, 1,3-dimethylurea and 1,3-diethylurea have been measured at 298.15 K. The enthalpic pair interaction coefficients of urea derivative molecule-NaI are determined using standard solution enthalpies of NaI in water and aqueous solutions of ureas.

Influence of ionic association on the B coefficient of the Jones–Dole equation for NaI in water–t-butyl alcohol mixtures at 26 °C

Values of the B coefficient of the viscosity of the Jones–Dole equation are reported for sodium iodide in the water–t-butyl alcohol system up to 90 mol % t-butyl alcohol at 26 °C. The calculation of the theoretical A coefficient of the Jones–Dole equation needs the ionic limiting conductivity data. The conductivity measurements of Bu4NI and NaBPh4 solutions in water–t-butyl alcohol mixtures at 26 °C were performed in order to divide the conductivity for NaI, known from our earlier investigations, into ionic contributions. The division is based on the assumption of Fuoss et al. that Λ0(Bu4N+)= 0.519Λ0(Bu4NBPh4).

Viscosity of solutions of NaI and CaCl2 in water–ethanol and of Nai in water–tetrahydrofuran mixtures

Viscosity measurements of solutions of NaI and CaCl2 in water–ethanol mixtures and of NaI solutions in water–tetrahydrofuran mixtures have been performed at 20, 25 and 30 °C. The salt concentration was 0.05 mol kg–1 of solvent. Minima in the relative viscosity corresponding to ca. 12 mol% ethanol and 2.5 mol% THF have been observed. The temperature coefficients of the relative viscosities have been calculated and interpreted from the viewpoint of the effect of the investigated electrolytes on the water–organic solvent mixtures. The dependence of ηr=f(organic solvent content) has been compared with the analogous relationship for the standard enthalpy of solution of the investigated salt. The correlation between ηr(or B)=f(ΔH°s) has been found to be linear over a wide region of mixed solvent compositions, not only in the mixtures of water with ethanol and THF but in other water–organic solvent systems.

Dissolution enthalpy of NaI in water–alcohol mixtures at 288.15 and 308.15 K. Enthalpy of interaction in electrolyte–alcohol–water systems

The enthalpy of NaI solution was determined in water mixtures with methanol, ethanol, propanol, and isopropanol in the entire range of mixed-solvent concentration at 288.15 and 308.15 K, and in water mixtures with s-butanol and tert-butanol in the range of 0–5 mol% alcohol at 308.15 K. The dependence of [Formula: see text] on solvent composition was studied. The enthalpic pair interaction coefficients hEN for NaI–alcohol in water and NaI–water in alcohols were determined, and the effect of temperature on hEN values in the systems under study was analyzed.