Bulk Thermodynamics Determines Surface Hydrogen Concentration in Membranes

Hydrogen ion concentration changes in mitochondrial membranes.

1. Bromthymol blue added to rat liver mitochondria at concentrations in the range 0.4 to 4.0 mpmoles per mg of protein is tightly bound as indicated by centrifugation and washing of the mitochondria. 2. The absorbance of the dye is increased on adding Ca++ or Mn++ to the mitochondria in the absence of a permeant anion. The extent of increase is 0.03 cm-l for 167 PM Ca++ at 618 rnp for 0.5 mpmol...

Surface and bulk elasticity determined fluctuation regimes in smectic membranes.

We report combined x-ray photon correlation spectroscopy (XPCS) and neutron spin echo (NSE) measurements of the layer-displacement fluctuations in smectic liquid-crystal membranes in the range from 10 ns to 10 micros. NSE reveals a new regime, determined by bulk elasticity, in which relaxation times decrease with the wave vector of the fluctuations. XPCS probes slower surface-tension-dominated ...

Concentration polarization, surface currents, and bulk advection in a microchannel.

We present a comprehensive analysis of salt transport and overlimiting currents in a microchannel during concentration polarization. We have carried out full numerical simulations of the coupled Poisson-Nernst-Planck-Stokes problem governing the transport and rationalized the behavior of the system. A remarkable outcome of the investigations is the discovery of strong couplings between bulk adv...

Steady concentration distribution of hydrogen in elastic membranes during hydrogen diffusion

A critical discussion on non-linear steady-state concentration profiles for hydrogen diffusion in elastic metallic membranes, proposed by other authors, is provided based on mathematical analysis and numerical simulation. It is shown that the non-linear distribution is non-existent and the linear form is the only solution for the ideal solid solution phase.  2000 Elsevier Science S.A. All righ...

Thermodynamics of quantum crystalline membranes