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Global tropospheric pollution models are developed that describe the transport and the physical and chemical processes occurring between the principal sources and sinks of CH4 and CO. Results are given of long term static chemical kinetic computer simulations and preliminary short term dynamic simulations.

Corrugated shape is easily machined for millimeter wave application and is better suited for folding antenna designs. Measured performance showed ""V'' corrugations and rectangular corrugations have nearly the same pattern beamwidth, gain, and impedance. Also, ""V'' corrugations have higher relative power loss.

Corrugated horns use corrugations on the E-plane walls that are operating in the cutoff condition. In this paper, attention is focused on replacing the rectangular shaped corrugation with a V-shaped corrugation. The properties of the V corrugations are obtained using an integral equation solution; the results of the computational studies indicate that for operation of the V corrugations in the forbidden zone the depth of the corrugations lie between 0.3125 to 0.625 times the wavelength in contrast to the rectangular corrugations where the corresponding depth is 0.25 to 0.5 times the wavelength. The radiation patterns and impedance of two identical rectangular horns with corrugated E-plane walls using either V or rectangular corrugations are directly compared.

The current status of a global pollution model for carbon monoxide, methane, and formaldehyde is described. The physico-chemical action is considered of these three pollutants in the troposphere. This geographic restriction is convenient since the tropopause provides a natural boundary across which little transport occurs. The data on sources and sinks for these pollutants is based on available information and assumptions relative to the major man-made and natural contributions. The distributions and concentrations of methane, formaldehyde, and carbon monoxide in the atmosphere are interrelated by the chemical reactions in which they participate. A chemical kinetic model based on the pseudo-steady state approximation for the intermediate species was developed to account for these reactions. The numerical procedure used to mathematically describe the pollution transport is a mass conservative scheme employing an integral flux approach.

Review of some new results obtained using the equivalent current technique to calculate caustic fields in a study of backscattering from a cone. The caustic region on the back of a conducting cone for an axially incident electromagnetic wave is shown to extend to a distance of the order of a half-wavelength from the center of the caustic, thus fixing the minimum size conducting body such as a cone that can be treated using the ray optical format.

Corrugated horns involve a junction between the corrugated surface and a conducting ground plane. Proper horn design requires an understanding of the electromagnetic properties of the corrugated surface and this junction. An integral equation solution has been used to study the influence of corrugation density and tooth thickness on the power loss, surface current, and the scattering from a ground plane/corrugated surface junction.

Discussion of the present state of the art of low-noise antennas, and speculation about some future achievements that can be anticipated in the light of present trends. Attention is focused on major means of generating side lobes and techniques that may be used to obtain improved side lobe performance. Antennas with no side lobes are also considered.

Measurements and calculations of gamma heating in polyethylene and lead containers were done and compared. The objective was to provide a workable method of getting good values for gamma heating in in-pile experiments containing materials of high atomic numbers. It was inferred that a combination of thermoluminescent dosimeter measurements, using Bragg-Gray theory, with photon transport calculations using the ANISN computer program, would meet this objective.

Calorimetric determination of reactor gamma source heating as function of specimens thickness and atomic number, discussing slab and cylindrical geometrical effects

Optimum fuel utilization for Plum Brook Reactor, using criticality data for effects of neutron leakage and burnup uniformity in core point model

Reaction kinetics of ozone oxidation of ethylene pertinent to air pollution

Thermal neutron absorber buildup in irradiated beryllium

Calorimetric determination of gamma heating of metals and carbon in reactors as function of thickness and atomic number

Wedge diffraction analyses of TE sub 10 mode slot radiation characteristics on circular and elliptical cylinder, considering boundary value solutions existence

Thermal neutron flux perturbations in cylinders in test reactors, using regression analysis to obtain polynomials for flux perturbation, depression, self shielding factors, etc

Equatorial radiation pattern of parallel plate TEM mode axial slot on elliptical conducting cylinders, using wedge diffraction and creeping wave theory

Edge diffraction effects in TEM axially slotted finite ground plane on radiation pattern in waveguides of different geometries

Radiation pattern of axial slot on circular conducting cylinder based on wedge diffraction and creeping wave theory

Prediction of thermal neutron flux perturbation effects in cylinders during irradiation tests

Corrugated horns involve a junction between the corrugated surface and a conducting groundplane. Proper horn design requires an understanding of the electromagnetic properties of the corrugated surface and this junction. Therefore, an integral equation solution has been used to study the influence of corrugation density and shape on the power loss. Surface current, and the scattering from a groundplane-corrugated surface junction. Both square and vee shape corrugations have been considered over the range of corrugation depths where the surface acts as a cut-off corrugated surface.

The corrugated horn is discussed as is a valuable tool for use in microwave pattern ranges. It has the properties of concentrated energy in the main beam, low backlobes, high efficiency, almost monotonic amplitude, and phase radiation patterns which make the corrugated horn useful for a source antenna in a pattern range and also as a possible standard antenna for calibration purposes.

Horn antennas of four types: pyramidal corrugated, conical corrugated, pyramidal dual mode and conical dual mode, have been constructed and evaluated for use as S-band radiometer antennas. Each of the structures is described and radiation patterns and impedance and resistive loss measurements including a layer of foreign material on a thin radome, are presented. A precision method for determining reflection losses is described using a multiprobe reflectometer technique. The same technique is also applied to the measurement of resistive losses by closing the ends of the antennas with short circuit plates and determining the losses from an accurate measurement of the reflection coefficient. The radiation patterns were recorded with the aid of a real-time digital computer. The stored patterns were then processed to yield gain and beam efficiency. It was concluded that it is possible to design a highly efficient antenna for radiometer use and to measure its parameters precisely. However, it was found that it is necessary to modify the conventional definition of beamwidth somewhat if this term is to be meaningful for radiometer applications.