In this study, a pulsed electric field (PEF) and an oscillating magnetic field (OMF) were used to achieve an extension of a supercooled state within chicken breasts. The specifications of protocol are: (i) PEF with duty cycle sequence of 0.8, 0.5, and 0.2 were applied for 300 sec, 120 sec, and 90 sec, respectively and (ii) during PEF with duty cycle of 0.2, OMF with 1 Hz was applied to vibrate water molecules and inhibit sudden ice nucleation. At the freezer temperature of-7°C (± 0.5), temperature of chicken breast samples under PEF and OMF treatment decreased down to-6.5°C in a supercooling state during the whole testing period (approximately 12 h); while the control samples were partially frozen down to-6.5°C. The impacts of the supercooling on microstructure, drip loss, color, texture, pH and lipid oxidation were evaluated as compared with samples stored at refrigeration (4°C) and at freezing (-7°C). It was found that the PEF + OMF supercooling was highly effective in the maintenance of original meat qualities without significant physical damages or chemical changes. The supercooling of meat samples using the developed PEF and OMF combination technique led to the advanced designing of innovative food freezers for long term preservation of 'fresh-like' foods at subzero temperature.

A three-dimensional total variation diminishing (TVD) algorithm is developed for computing unsteady/steady flows in pulsed lasers. The general approach utilizes a three-dimensional thin-layer Navier-Stokes/Euler solver with source terms in the main channel, a one-dimensional Euler solver with source terms in the sidewall-muffler backing volume, and a quasisteady channel to backing volume flow-exchange model. Explicit time integration of these equations is accomplished via symmetric TVD formulations in an effort to enhance accuracy of the computed solution. Shock-tube experiments are performed to generate a data base for generic laser related problems and are shown to compare well with the computed solutions. Some aspects of laser flow/acoustic design are then discussed to demonstrate the capability of the code to supplement an overall flow system design effort. Nomenclature a -acoustic speed C d = discharge coefficient (muffler wall) K ml = normalized linear resistance in muffler backing volume, K m Llp r u r K mn = normalized nonlinear resistance in muffler backing volume, K mn L K r = normalized linear resistance of muffler wall, KJp r u r L = reference length p -dimensional pressure t -dimensional time u r -reference velocity, a 0 a = open area ratio (muffler wall) y = ratio of specific heats p r = reference density, p 0

The effect of a high aerosol concentration on the creased. It was also found that when the value of the collection efficiency of impactors has been studied. TheReynolds number or the overall particle sizes inflow was assumed to be dilute and two-way coupled. A creased, the change of the collection efficiency by the particle source in cell model for the computational change of the aerosol concentration also increased. scheme was used. Results show that the effect of the The effect of the high aerosol concentration on the particle interactions with the air on the collection efficollection efficiency was found to be considerable even ciency is enlarged as the aerosol concentration is inin slow flows when particles are large.

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