The authors have developed a novel technique using Zinc-Iron-appropriately particlate zinc-iron alloy, each particle having an iron nucleus-, as the ejection material for the mechanical plating of steel. This paper reports the results of studies on the characteristics necessary for successful mechanical plating of Z-iron onto various steels. The principal results obtained employing a laboratory size ejecter are as follows;
(1) There is a Vickers hardness range for which efficient high-deposit density mechanical plating of Z-iron can be effected; thermal treatment of the Z-iron is extremely beneficial in reducing the time required for plating and increasing plating density.
(2) Deposit density increases with an increase in the amount of both ZZ-48 and ZZ-48H, plated reaching a stable maximum value at an amount that is characteristic of the material. With ZZ-48H a maximum deposit density of 1500mg/dm² was obtained at a feed amount of not less that 5000 grams, while the value for ZZ-48 was 650mg/dm² at not less than 3500 grams.
(3) With repeated ejection, changes in the properties of Z-iron led to lower-quality mechanical plating. A decrease in deposit density was observed with an increase in the number of ejections. Plating by ZZ-48H was characterized by longer life and higher deposit density than ZZ-48.

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The properties of platinum oxide film electrodes were studied to improve stability of an electrochemical HF-gas sensor. The thin-film electrodes were prepared by reactive sputtering on the surface of a PTFE (polytetrafluoroethylene) membrane in a mixture of argon and oxygen.
Total sputtering pressure was kept constant at 8×10^-3Torr and oxygen pressure was varied from zero to 1.6× 10^-4Torr. To clarify the surface properties of the film, the structure and the chemical binding state were analyzed by XRD and ESCA. The crystalline structure of the film changed from Pt to PtO at an oxygen pressure of 1.2×10^-5Torrd and changed to PtO₂ with increasing oxygen pressure. An HF-gas sensor using this platinum oxide thin-film electrode showed stable gas sensitivity for a prologed period, maintaining stable output current for at least 200 days, under normal conditions at room temperature.

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The effects of stirring on the electroplating of copper have been investigated in an aqueous CuSO₄-H₂SO₄ solution using a cylindrical cell in which the inner cathode was rotated and the outer anode was fixed.
The discharge mechanism of cupric ion was found to be independent of overpotential and rotation speed under the limiting current density. The morphology of the copper deposit was little influenced by rotation speed when cathodic overpotential was lower than -0.16V. At high overpotential (|η|>0.33V), the surface of the deposit became smooth as the rotation speed increased under laminar flow conditions, whereas under turbulent flow conditions smooth deposits were always observed even at 70A/dm² due to a remarkable decrease in the thickness of the diffusion layer.
The preferred orientation of the {110} plane appears only at high rotation speeds owing to the acceleration of nucleation, especially at an overpotential of -0.33V. No characteristic preferred orientation appeared under laminar flow conditions.

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Cobalt blue films were prepared on aluminum by a two-step anodic oxidation process. Aluminum plate was anodized in sulfuric acid by direct current and cobalt was deposited into the pores of the film by AC electrodeposition. The alumina film with deposited cobalt was then reanodized in a molten mixture of sodium bisulfate and ammonium bisulfate.
The surfaces of cobalt blue films formed in the bisulfate melt were porous and their X-ray diffraction patterns indicated the crystalline structure of a defective spinel, CoO·3Al₂O₃, which constitutes cobalt blue pigment.

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