I t is known that the yield of staphylococcus toxin in plain broth and other fluid media is poor (1). The use of solid or semisolid agar media appears necessary for producing active preparations. Recently, however, McClean (1) was able to obtain potent toxins by the use of fluid media diffused through cellophane bags. The surface of the cellophane membrane appeared to play a r61e similar to tha...

Two different approaches in the inverse halftoning of error-diffused images are considered. The first approach uses linear filtering and statistical smoothing that reconstructs a gray-scale image from a given error-diffused image. The second approach can be viewed as a projection operation, where one assumes the error diffusion kernel is known, and finds a gray-scale image that will be halftone...

Axial Magnetic Field (AMF) is widely used in vacuum interrupters to keep the arc in the diffused mode. With increasing axial magnetic field, the multiple arc mode extends to higher arc currents. In this mode of arc, the fault current can be easily interrupted due to fast recovery of the diffused vacuum arc. The magnetic field amplitudes considered in the preceding studies are all less than hund...

When long polymers such as DNA are in a highly concentrated state they may become entangled, leading to restricted self-diffusion. Here, we investigate the effect of molecular topology on diffusion in concentrated DNA solutions and find surprisingly large effects, even with molecules of modest length and concentration. We measured the diffusion coefficients of linear and relaxed circular molecu...

Molecular dynamics simulation was used to calculate rotational relaxation time, diffusion coefficient, and zero-shear viscosity for a pure aromatic compound (naphthalene) and for aromatic and aliphatic components in model asphalt systems over a temperature range of 298-443 K. The model asphalt systems were chosen previously to represent real asphalt. Green-Kubo and Einstein methods were used to...

A discrete-bubble model that predicts the rate of oxygen transfer in diffused-bubble systems is evaluated. Key inputs are the applied gas flow rate and the initial bubble size distribution. The model accounts for changes in the volume of individual bubbles due to transfer of oxygen and nitrogen (and hence changing partial pressure), variation in hydrostatic pressure, and changes in temperature....