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The objectives of this document are to present an overview of the work accomplished to date on desiccant cooling to provide assessment of the state of the art of desiccant cooling technology in the field of desiccant material dehumidifier components, desiccant systems, and models. The report also discusses the factors that affect the widespread acceptance of desiccant cooling technology. This report is organized as follows. First, a basic description and historical overview of desiccant cooling technology is provided. Then, the recent research and development (R D) program history (focusing on DOE's funded efforts) is discussed. The status of the technology elements (materials, components, systems) is discussed in detail and a preliminary study on the energy impact of desiccant technology is presented. R D needs for advancing the technology in the market are identified. The National Renewable Energy Laboratory's unique desiccant test facilities and their typical outputs are described briefly. Finally, the results of a comprehensive literature search on desiccant cooling are presented in a bibliography. The bibliography contains approximately 900 citations on desiccant cooling.

A technique is presented for in situ study of degradative changes in polymeric coatings on metallic substrates. The technique uses a controlled environment chamber in conjunction with a Fourier-transform infrared (FT-IR) spectrophotometer. The chamber design permits collection of IR reflection-absorbance spectra from a sample undergoing exposure to controlled ultraviolet (uv) radiation, gas mixtures, and temperatures. Initial data presented confirm the ability of the technique to provide information regarding the bulk photochemistry of bisphenol-A polycarbonate coatings on gold and aluminum substrates. Refinements of this technique should allow a detailed kinetic study of degradative reactions at the polymer/metal interface.

This report describes the experimental work and results from the second phase of the Matrix Approach to Testing Mirrors (MATM). Mirror specimens are subjected to heat, water vapor, pollutants, ultraviolet light, and mechanical stress for up to eight weeks. Analysis concluded that the degradation rates are very sensitive to temperature; above 95/sup 0/ to 100/sup 0/C, agglomeration causes the silver film to degrade rapidly; degradation is more severe in high humidity pollutants did not substantially alter the degradation rates; ultraviolet light did not significantly alter the degradation of solar reflectance; no synergistic effects were observed; specular and hemispherical reflectance techniques detect and quatify the early stages of degradation; and darkfield microphotography is a good technique for studying mirror degradation.