Abstract: A method and apparatus for sharpening clockwise rotating standard blades, counter-clockwise rotating standard blades and mulching style blades of either clockwise or counter-clockwise rotation is provided. The present invention comprises a base with a blade fixture which is reversible to accommodate both clockwise and counter-clockwise rotating blades. Uprights, a slide shaft, a slide bushing and a handle shaft connected to a disc grinder provide a means for setting a primary cutting angle for sharpening the primary cutting edges of a blade. An adjusting wheel rotatable attached to the handle shaft and pivotably coupled to the disc grinder provide a means for quickly and easily adjusting the cutting angle in order to accommodate sharpening the secondary cutting edges of a mulching style blade and returning the disc grinder back to its original cutting angle.

Abstract: A method and apparatus for sharpening clockwise rotating standard blades, counter-clockwise rotating standard blades and mulching style blades of either clockwise or counter-clockwise rotation is provided. The present invention comprises a base with a blade fixture which is reversible to accommodate both clockwise and counter-clockwise rotating blades. Uprights, a slide shaft, a slide bushing and a handle shaft connected to a disc grinder provide a means for setting a primary cutting angle for sharpening the primary cutting edges of a blade. An adjusting wheel rotatable attached to the handle shaft and pivotably coupled to the disc grinder provide a means for quickly and easily adjusting the cutting angle in order to accommodate sharpening the secondary cutting edges of a mulching style blade and returning the disc grinder back to its original cutting angle.

Abstract: It has been found that a small amount of alkylene oxide prevents Pt-Co color buildup in mono, di and triethanolamine. Alkylene oxide also reduces undesirable blue, aqua or straw hues which may develop.

Abstract: A method of eliminating color-causing impurities in mixtures of aminoethylpiperazine, polyoxypropylenediamines and alkylphenols by treatment with N,N-diethylhydroxylamine is described. These alkylphenols such as nonylphenol are used in epoxy resins in the automotive and electronics industry. Discoloration of the phenol and subsequent resin occurs if the phenol is not treated with N,N-diethylhydroxylamine. Quantities on the order of 20 to 500 ppm are effective. The decolorization reaction may be conducted at a temperature in the range from about 25.degree. to 50.degree. C.