Search results for "Salt"
showing 10 items of 1157 documents
2021
Water-in-salt systems, i.e., super-concentrated aqueous electrolytes, such as lithium bis(trifluoromethanesulfonyl)imide (21 mol/kgwater), have been recently discovered to exhibit unexpectedly large electrochemical windows and high lithium transference numbers, thus paving the way to safe and sustainable charge storage devices. The peculiar transport features in these electrolytes are influenced by their intrinsically nanoseparated morphology, stemming from the anion hydrophobic nature and manifesting as nanosegregation between anions and water domains. The underlying mechanism behind this structure-dynamics correlation is, however, still a matter of strong debate. Here, we enhance the apol…
1,3-Dimethylimidazolium-2-carboxylate: the unexpected synthesis of an ionic liquid precursor and carbene-CO2 adductElectronic supplementary informati…
2002
1,3-Dimethylimidazolium-2-carboxylate is formed in good yield, rather than the anticipated organic salt, 1,3-dimethylimidazolium methyl carbonate, as the reaction product resulting from both N-alkylation and C-carboxylation of 1-methylimidazole with dimethyl carbonate; the crystal structure of the zwitterion exhibits π-stacked rings and two-dimensional sheets constructed by hydrogen-bonds from imidazolium-ring hydrogens to the carboxylate group.
Mineral content of seasonings, salt and vinegar
2015
EFFECT OF MOISTURE ON THE BULK PROPERTIES OF SALTED POLY(CAPROAMIDE).
1980
The glass-transition temperature (Tg) and the elastic modulus of nylon-6 and its mixtures with 4% w/w LiCl and with 2% LiCl+3% LiBr were investigated. In one set of experiments care was taken to avoid absorption of moisture during the measurements. In another set of experiments, samples were exposed to atmospheric humidity for different lengths of time. Both unoriented and oriented specimens were investigated. The presence of 4% LiCl almost doubles the amount of moisture absorbed at equilibrium by nylon-6. The Tg was found to be greatly affected by the moisture content and by salt type. When strict precautions to exclude moisture are taken, the addition of 4% LiCl raises the Tg of nylon-6 b…
Polyelectrolytes in dilute solution: viscometric access to coil dimensions and salt effects
2015
Copolymers of acrylamide (AM) and diallyldimethylammonium chloride (DADMAC), differing in molar masses M (52.3 to 227 kDa) and degrees of charging y (0.2 to 0.6), were studied with respect to their viscometric behavior in dilute aqueous solutions containing variable amounts of NaCl. Complementary measurements were performed on a Brookhaven 90 plus particle size analyzer. M dominates the intrinsic viscosities [η]. For the viscometric interaction parameters B this is only true for large concentrations of extra salt. [η] and B as a function of solvent salinity follow Boltzmann laws. Coil dimensions, determined either via dynamic light scattering or viscometry, agree well. For low salt contents…
Consequences of linking charged and uncharged monomers to binary copolymers studied in dilute solution. Part I: Viscometric behavior of the homopolym…
2017
Abstract Intrinsic viscosities, generalized intrinsic viscosities and viscometric interaction parameters were measured for aqueous solutions of poly(ethylene oxide) [PEO], poly(N,N-dimethyl aminoethyl methacrylate) [PR] (uncharged) and for poly{[2-(methacryloyloxy)ethyl] trimethylammonium iodide} [PR+] (charged) within a wide range of molar masses. In this manner it was possible to establish the information required for the study of non-additivity effects upon the formation of binary copolymers from the monomers specified above. The following additional items were of particular interest: The effects of charging PR to PR+ and the composition dependence of the coil overlap in the case of sali…
Viscometry of polyelectrolyte solutions: Star-like versus linear poly[[2-(methacryloyloxy)ethyl] trimethylammonium iodide] and specific salt effects
2017
Abstract The intrinsic viscosities, [η], of the 3-arm star polyelectrolyte in pure water are for a given molar mass considerably lower than for the linear product because of the higher monomer concentration and charge density in isolated coils. These effects are much more pronounced than in the case of uncharged macromolecules. Extra salt (NaCl, NaI, CaCl2) reduces the solution viscosities of the 3-arm star polymer less than of the linear product. The transition of [η] from the value in pure water to the minimum saturation value at high salt concentrations follows a Boltzmann sigmoid. In saline solvents the changes of the viscosities with rising polymer concentration depend strongly on the …
The [3,3′-Co(1,2-C2B9H11)2]– anion as a platform for new materials: synthesis of its functionalized monosubstituted derivatives incorporating synthon…
2003
[3,3′-Co(8-C5H10O-1,2-C2B9H10)(1′,2′-C2B9H11)] (2) was synthesized by reaction of the caesium salt of [Co(C2B9H11)2]− with dimethyl sulfate in the presence of sulfuric acid as catalyst and tetrahydropyrane as solvent; the zwitterionic compound (2) yielded [3,3′-Co(8-C4H4N-(CH2)5-O-1,2-C2B9H10)(1′,2′-C2B9H11)]− (6), [3,3′-Co(8-C8H6N-(CH2)5-O-1,2-C2B9H10)(1′,2′-C2B9H11)]− (7), and [3,3′-Co(8-C12H8N-(CH2)5-O-1,2-C2B9H10)(1′,2′-C2B9H11)]− (8) through the nucleophilic addition of potassium pyrrolyl, indolyl and carbazolyl, respectively. The nucleophilic addition of the same salts on [3,3′-Co(8-C4H8O2-1,2-C2B9H10)(1′,2′-C2B9H11)] (1) yielded, respectively, [3,3′-Co(8-C4H4N-(CH2)2-O-(CH2)2-O-1,2-C…
Stability of ascorbic acid in adapted milk-based infant formulae during storage
2004
A study was made of the effects of storage (for up to 17 months at 22 or 37 °C) on the ascorbic acid contents of four adapted milk-based infant formulae with the same composition except for the iron salt added (lactate or sulphate) and/or the vitamin E source involved (α-tocopherol (α-T) or α-tocopherol acetate (α-TAc)). Ascorbic acid was measured by a voltammetric method. The ascorbic acid contents of the formulae ranged from 0.77–0.84 g kg−1 immediately after manufacture to 0.41–0.48 g kg−1 after 17 months of storage. Samples stored at 22 °C had higher ascorbic acid contents than those stored at 37 °C. A multiple regression analysis performed to evaluate ascorbic acid evolution throughout…