Richard Conley La Force

Theory of Oxygen Transport through Hemoglobin Solutions

A combination of equations describing diffusion, gas solubility, and mass conservation yields a general relation for oxygen transport in hemoglobin solutions. Total oxygen flux is shown to be the sum of the flux in the plasma and the flux due to transport by hemoglobin. The total flux depends not only on oxygen concentration gradient but also on absolute oxygen concentration.

The temperature dependence of the nuclear magnetic resonance of Co59

Abstract The temperature dependence of the nuclear magnetic resonance spectrum of pure cobalt from 25°C to 600°C has been re-examined with the aid of more sensitive apparatus. The resonances from the hexagonal phase disappear at 490°C on heating and re-appear at 440°C on cooling. The principal resonance lines of the face-centered-cubic and hexagonal phases start to split into two lines each at about 235°C and 260°C, respectively; the fractional splitting increases with temperature, and is approximately the same for the two phases. The absolute intensities of the split resonances decrease in an externally applied magnetic field, but the relative intensities are independent of the external field.

Steady-state diffusion in the carbon monoxide + oxygen + haemoglobin system

The experimental work of Mochizuki and Forster indicates that the characteristics of diffusion in the carbon monoxide + oxygen + haemoglobin system cannot be understood if it is assumed that equilibrium exists between the reacting species at the initial and final boundaries of the transport path. It is shown herein, however, that if the differential equations governing steady-state diffusion with simultaneous chemical reaction are solved without this simplifying assumption, a decision can be made between two possible mechanisms for the reaction kinetics and values for the diffusion coefficients and rate constants can be obtained by comparing the calculated steady-state fluxes with the experimental data.

Device to measure the voltage-current relations in biological membranes.

A device has been designed and constructed, largely of commercially available operational amplifiers, to measure the voltage‐current relations in biological membranes due to the ion flux through them. The device operates in three modes: to clamp the voltage across the membrane to some predetermined value and record the current, to clamp the current through the membrane and record the trans‐membrane voltage, and to record dV/dI, the resistance of the membrane measured in a time short compared to the ion redistribution time.

Device for the Precise Measurement of Small Temperature Changes

A device capable of measuring temperature with a precision corresponding to a standard deviation of about 14 microdegrees at room temperature has been designed and constructed. The device employs a thermistor as the temperature‐sensing element in an ac bridge. The bridge imbalance, after being amplified, is detected by two phase‐sensitive detectors phase‐shifted 90° with respect to each other to insure that both the resistive and reactive components of the bridge elements are balanced.

The ESR line shape of free radicals in aqueous environments

We have calculated the line shape to be expected in the electron spin resonance spectra from free radicals in an aqueous environment. We have assumed microwave power to be incident from the left on a planar sample transverse to the waveguide, and that the transmitted power is detected to the right of the sample. We consider two kinds of samples: a solution of free radical of thickness [inverted lazy s] 1 cm, and a thin membrane of thickness [inverted lazy s] 0.1 mm containing free radicals and bathed on each side by a water solution of thickness [inverted lazy s] 0.5 cm. The line shape is markedly affected by the presence of water for each kind of sample. When the unpaired spins are confined to a thin membrane bathed with water, the line shape changes from absorptive to dispersive to absorptive of the opposite phase as a function of the dielectric constant of the sample region. We conclude from the calculation that the presence of thick aqueous regions can be exploited to obtain new information from exper...