Abstract: A forest fire retardant composition contains a retardant compound that includes a potassium salt. The potassium salt may include a potassium salt of an organic acid, a potassium salt of an inorganic acid, or mixtures thereof. The organic acid may include formic acid, acetic acid, propanoic acid, butanoic acid, lactic acid, oxalic acid, malic acid, gluconic acid, tartaric acid, uric acid, malic acid, or citric acid. The inorganic acid may include sulfuric acid, phosphoric acid, carbonic acid, or hydrochloric acid. The composition may be in the form of a dry concentrate, a liquid concentrate, or a final diluted product. The final diluted product is effective in suppressing, retarding, and controlling forest fires while exhibiting corrosion resistance and low toxicity.

Abstract: Microwave communication and radar systems that employ a blazed microwave reflection grating are disclosed in which the grating comprises an array of electrical conducting scattering elements having plane parallel surfaces that face in the same direction. The plane parallel faces are positioned in parallel equally-spaced planes to provide a generally stair-step, or Venetian-blind type structure. Microwave energy beamed onto the plane parallel surfaces of the array exits at a diffraction-mode angle within the reradiation pattern of the individual scattering elements of the array. Frequency steering of the exit beam in one plane of the array is provided by varying the frequency of the illuminating beam.