A. Water Exchange 2326 B. Proton Exchange 2327 C. Electronic Relaxation 2327 D. Relaxivity 2331 E. Outerand Second-Sphere Relaxivity 2334 F. Methods of Improving Relaxivity 2336 V. Macromolecular Conjugates 2336 A. Introduction 2336 B. General Conjugation Methods 2336 C. Synthetic Linear Polymers 2336 D. Synthetic Dendrimer-Based Agents 2338 E. Naturally Occurring Polymers (Proteins, Polysaccharides, and Nucleic Acids) 2339

https://mriquestions.com/uploads/3/4/5/7/34572113/lauffer_1999_review.pdf

Gadolinium(III) Chelates as MRI Contrast Agents: Structure, Dynamics, and Applications

Lithium-ion batteries raise safety, environmental, and cost concerns, which mostly arise from their nonaqueous electrolytes. The use of aqueous alternatives is limited by their narrow electrochemical stability window (1.23 volts), which sets an intrinsic limit on the practical voltage and energy output. We report a highly concentrated aqueous electrolyte whose window was expanded to ~3.0 volts with the formation of an electrode-electrolyte interphase. A full lithium-ion battery of 2.3 volts using such an aqueous electrolyte was demonstrated to cycle up to 1000 times, with nearly 100% coulombic efficiency at both low (0.15 C) and high (4.5 C) discharge and charge rates.

"Water-in-salt" electrolyte enables high-voltage aqueous lithium-ion chemistries.

Artificial Organic Host Molecules for Anions

Structure and nanostructure in ionic liquids.

4. Structure of Ionic Hydration Shells 1351 4.1. Results from Diffraction Experiments 1351 4.1.1. X-ray Diffraction 1351 4.1.2. Neutron Diffraction 1351 4.2. Results from Computer Simulations 1352 4.3. Results from Spectroscopic Measurements 1354 4.3.1. Vibrational Spectroscopic Measurements 1354 4.3.2. EXAFS Spectroscopy 1354 4.3.3. NMR Relaxation Studies 1355 4.3.4. Dielectric Relaxation Studies 1355 4.4. Summary of the Structure of Ionic Hydration Shells 1355

Effect of ions on the structure of water: structure making and breaking.

Complexation of silver(I) with glycinate (gly−) and β-alaninate (β-ala−) ions have been studied by potentiometry and calorimetry in 0.2 mole fraction (55.0 %w/w) dioxane–water mixture containing 3 mol dm−3 LiClO4 as a constant ionic medium at 25 °C. Potentiometric titration curves obtained were well-explained in terms of formation of [AgL], [AgL2]−, and [AgHL]+ (L−=gly− or β-ala−) in both systems, together with [Ag(OH)L]− in the Ag(I)–β-alanine system, and their formation constants were determined. Enthalpies of formation of the complexes in the mixed solvent, as well as in water containing the same ionic medium, were calorimetrically determined on the basis of the formation constants potentiometrically determined. Solubilities and enthalpies of solution of the neutral [AgL] (L−=gly− and β-ala−) complexes and some related compounds were determined in water and the mixture, the Gibbs energies of transfer, ΔGt°, of silver(I) ion and proton from water to the mixture being also determined by potentiometry. By...

Thermodynamic Quantities of Transfer of Glycinato and β-Alaninato Complexes of Silver(I) and Related Species from Water to an Aqueous Dioxane Solution

Stability constants of the hydrolysis species of UO22+ ion were determined in pure light water and 80% heavy water containing 3M NaClO4 as an ionic medium at 25°C, and the results were compared with those in pure heavy water. The decrease of the stability constants in hydrolysis reactions of UO22+ ion, as well as of Be2+ ion, was discussed in terms of the equilibrium theory of the solvent deuterium isotope effects, which is based on the assumptions that activity coefficients of chemical species in isotopic exchange equilibria remain unchanged with the change in the deuterium atom fraction in the solvent, that the solvated hydrogen ion possesses three equivalent lyons, and that the isotopic equilibria are subject to the rule of the simple geometric mean. Satisfactory agreements were found between the observed and calculated values for the relative stability constants of the hydrolysis species of UO22+ and Be2+ in water of various hydrogen isotopic compositions.

Mixed Solvent Deuterium Isotope Effects on the Hydrolysis of UO22+ and Be2+ Ions

Ion-exchange equilibria in the concentrated solutions of magnesium chloride-hydrochloric acid and aluminum chloride-hydrochloric acid system were studied. Amounts of the water present in the resin at equilibrium were estimated for these systems. In the magnesium chloride-hydrochloric acid system a large part of magnesium in the resin exists as MgCl+ at equilibrium when the concentration of hydrochloric acid is high. Selectivity coefficients of magnesium chloride-hydrochloric acid and of aluminum chloride-hydrochloric acid systems were calculated.

Ion Exchange in Concentrated Solutions. III. Magnesium Chloride-Hydrochloric Acid and Aluminum Chloride-Hydrochloric Acid Systems

Dissociation constants of protonated 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, and 1,12-dodecanediamine in aqueous mixtures of 0 to 90% (w/w) methanol were determined potentiometrically at 25°C, 0.1 M sodium chloride being used as an ionic medium. Values of pK2–pK1 of diamines were practically independent of the solvent composition in contrast to those of dicarboxylic acids, which increase monotonously with methanol concentration. Variations of pK1, pK2, and pK2–pK1 of diamines with solvent composition were discussed in comparison with those of dicarboxylic acids.

Ionic Equilibria in Mixed Solvents. VIII. Solvent Effects on the Dissociation of Diprotic Acids in Aqueous Methanol Mixtures

Protonation equilibria of glycinate (gly−) ion and complex formation equilibria between nickel(II) and glycinate ions have been studied by potentiometry and calorimetry in water and in 0.2 mole fraction (55.0%w/w) dioxane–water mixture, each containing 3 mol dm−3 LiClO4 as a constant ionic medium at 25 °C. A series of mononuclear complexes, [NiLn](2−n)+ (L−=gly− and n=1–3) were found in both solutions and their formation constants, enthalpies and entropies were determined. It elucidated that the stepwise Gibbs energies of formation of the metal complexes varied in the sequence, ΔG1° ΔH2°>ΔH3°, and thus, the stepwise entropies markedly decreased in the order, ΔS1°>ΔS2°>ΔS3°. The result was discussed in relation to changes in the metal–water and metal–ligand bond lengths within [NiLn(H2O)6−2n](2−n)+ (n=1–3) with n. As to the solvent effects, the formation constants of each metal complex increased with the addition of dioxane to water, the increase was caused by b...

Hitoshi Ohtaki

Papers

Thermodynamic Quantities of Transfer of Glycinato and β-Alaninato Complexes of Silver(I) and Related Species from Water to an Aqueous Dioxane Solution

Mixed Solvent Deuterium Isotope Effects on the Hydrolysis of UO22+ and Be2+ Ions

Ion Exchange in Concentrated Solutions. III. Magnesium Chloride-Hydrochloric Acid and Aluminum Chloride-Hydrochloric Acid Systems

Ionic Equilibria in Mixed Solvents. VIII. Solvent Effects on the Dissociation of Diprotic Acids in Aqueous Methanol Mixtures

Potentiometric and calorimetric studies on formation of glycinato complexes of nickel(II) in water and in an aqueous dioxane solution.