A new caged proton, 2-methoxy-5-nitrophenyl sulfate, was synthesized and used in time-resolved pH jump experiments to study proton binding in the sarcoplasmic reticulum Ca-ATPase. The major advantage of this compound is that it does not produce significant artifacts in experiments in which the fluorescent styryl dye 2BITC is used to monitor ion movements in the Ca pump. Two rate-limiting proces...

Although there have been a number of studies on the ingestion of asbestos, few studies exist on how the chrysotile asbestos itself is altered by the exposure to the acid stomach environment. This study has found that there are changes in the physical, chemical and surface properties of chrysotile asbestos as a result of exposure to water, strong acids, and simulated gastric juices. It was obser...

The formation of a H˙ atom in liquid water from the reaction of a hydrated electron with a hydronium cation is a very challenging subject in chemical processes. Here picosecond pulse radiolysis measurements are performed at elevated temperatures, up to 350 °C, of acidic H2O and D2O solutions (up to 0.1 mol L(-1) HClO4) with the aim of investigating several issues related to this reaction. First...

ion mechanism, discussed in section 1.1.2. Figure 27 illustrates the reactive scattering mechanism with four representative snapshots of a Cs scattering trajectory in a classical MD simulation. The abstraction reaction is driven by the ion−dipole attraction force between the Cs ion and an adsorbate molecule. The impinging projectile first releases part of its initial energy to the surface (Figu...

The effect of concentration, molar ratios of reagents, pH, and temperature on formation of chloro-organic products in reaction of tert-butyl ethers with chloride ions and hydrogen peroxide has been determined. A significant effect of Cl(-) ions and H(2)O(2) molar ratios on the rate of chloro-organic product formation has been observed. Studies on oxychlorination of tert-butylethyl ether (ETBE) ...

The microscopic structure and dynamics of an excess proton in water constrained in narrow graphene slabs between 0.7 and 3.1 nm wide has been studied by means of a series of molecular dynamics simulations. Interaction of water and carbon with the proton species was modeled using a multistate empirical valence bond Hamiltonian model. The analysis of the effects of confinement on proton solvation...

The transport process of proton and water through a porous exchange membrane (PEM) under pressure difference is significant to fuel cell performance. Nonequilibrium molecular dynamics simulations were conducted investigate the diffusion mechanisms hydronium ions molecules differences. Here, different driving forces (0.15 kcal/(mol·Å)–0.45 kcal/(mol·Å)) applied as they transported Nafion 117 at ...

The properties of the water network in concentrated HCl acid pools nanometer-sized reverse nonionic micelles were probed with TeraHertz absorption, dielectric relaxation spectroscopy, and reactive force field simulations capable describing proton hopping mechanisms. We identify that only at a critical micelle size W0=9 do solvated complexes form pool, accompanied by change mechanism from Grotth...