provide a weight ratio of zinc to nickel of at least 10-l; a phosphorus-containing reduc- ing agent; complexing agent; and a buffer sufficient to achieve a basic pH of at least 12; and then contacting the substrate for a time and at a temperature sufficient to electrolessly deposit a solid coating con- taining at least 60 atomic percent zinc, and also containing nickel, and phosphorus.

Electroless Bismuth Plating Bath U.S. Pafent5,308,335. Apr. 26, 1994 A. Senda et al., ass@wts to Murata Manufacturing Co. Ltd., Kyoto, Japan

An electroless bismuth plating bath, comprising a trivalent salt of bismuth, a reducing agent, the reducing agent com- prising a bivalent water-soluble compound of tin, and complexing agent.

Electroless Nickel Plating Bath U.S. Pafent5,306,334. Apr. 26, 1994 N.M. Mattyak and B. F. Monzyk, assignors to Mon- santo co., Sf. Louis

An electroless nickel plating solution consisting essentially of nickel salt, one or more organic acids selected from the group consisting of lactic acid, acetic acid, propi-

onic acid, pyruvic acid, aspartic acid and glycolic acid, hypophosphite reducing agent, thiourea and ammonia and essen- tially no heavy metal, wherein the concen- tration of thiourea is less than 1 ppm, wherein the pH of said solution is alkaline.

Blast Media Containing Magnesium Oxide U.S. Patent 5.303403. May 3, 1994 B.S. Yam and A. E. Winston, assignors to Church & L%wght Co. Inc., Primeton, N.J.

A method of blast cleaning a solid surface comprising, propelling an abrasive blast media by means of a water-containing pressurized fluid stream to strip coatings or other contaminants, said blast media com- prising water-soluble abrasive particles and a magnesium oxide rinse aid effective to reduce blast media residues.

Tin-Bismuth Plating System U.S. Patent 5,308,4&f. May 3, 1994 TI. Murphy and B. Ft. Reynotds, assignors to Unisys Corp., Blue Bell, Pa.

A system for the electrodeposition of a near eutectic tin-bismuth alloy on an elec- trically conductive substrate connected as a

cathode to an electrical power source, the system comprising means for containing an aqueous electroplating bath and for sup- porting the electrically conductive sub- strate; an aqueous electroplating bath com- prising a concentration of methane sulfonic acid, stannous ions, and bismuth ions; and at least one bismuth anode immersed in the plating bath connected to the electrical power source.

Platinum Electroforming Process U.S. Patenf 5,310,475. May 10, 1994 K. Kitada and S. Yaffta, assignors to Electroptating Engineers of Japan Ltd.

A method for preparing a platinum product having a hardness in excess of 100 6 consisting essentially of electrodepos- iting a layer of platinum material onto a die having a predetermined shape in a platinum electrolytic bath, with said die having been coated with a release material, wherein the platinum electrolytic bath comprises at least one compound selected from the goup consisting of chloroplatinic acid, chloro- platinates of alkali metals, hydrogen hex- ahydroxoplatinate, and hexahydroxoplati-

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