Amount of platinum electrodeposition becomes greater when a surface of electrode, current density, bath concentration and bath temperature increase, but the increase rate of electrodeposition somewhat drops when the surface area of electrode becomes above 0.01dm², current density above 5A/dm², platinum content in 1l solution above 13g, content of Na₂HPO₄⋅12H₂O above 180g, that of (NH₄)₂HPO₄ above 16g or bath temperature above 70°C.
What control the amount of platinum electrodeposition most are bath temperature and current density.
The amount of platinum content is rather important as it controls the brightness of plating surface and time of plating.

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Electrochemical properties of depolarized Nickel Anode in Co-Ni alloy bright plating bath were studied. The conclusion of this reserch is as follows:
(1) Anode slime gathered in anode bag was 1.956% in average for dissolved anode metal in Co-Ni alloy bright plating bath.
(2) Anode current efficiency was very high and the surface corroded was smooth and there was no massive slime from anode. So, there was a little change of metallic constituent in plating solution and the maintainance of the bath was easy.
(3) The metallic ion consumed during plating including drag out loss was 84.46% in average from anode and 15.54% in average from salt added.
(4) There was no influence of the throwing power on cathode in the case of the depolarized nickel anode.

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When the chromium steel is heated in the atmosphere, containing the appreciable amount of oxidizing gas such as moisture and carbon dioxide, it is oxidized and discolored due to the low dissociation pressure of the chromium oxides. We studied, in this experiments, the effects of gas constituents in the atmosphere and heating temperature, the chromium content in steel to the surface brightness and the nitriding effect of steel.
As the results of this experiments, low chromium steel is heated without surface discoloration and decarburization in the atmosphere of hydrogen, hydrogen and nitrogen or (hydrogen, nitrogen and carbon monoxide) gas which have low moiature content.
The heat-treatment of high chromium steel becomes comparatively easy as the heating temperature get higher. The nitrogen content of the steel tends to increase as the partial pressure of nitrogen increases, and decrease as the chromium content of the specimen increases.

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Measurements of the surface potential under standardized condition of a number of metals such as Al, Zn, Cr, Ni, Ti, Cu, Fe, Ag, Au, Pt and brass, together with determinations of the adhesive strength of these metals under the same condition for polar and nonpolar organic coatings have been carried out. As a result, it is revealed that for metals which are lower in surface potential and accordingly less surface-oxidizable than Cu, adhesion strength increases almost proportinally to surface potential, but on the contrary, for metals having higher surface potential than Cu, adhesive strength is inversely proportional to surface potential. This latter inverse relation may be interpreted as due to the effect of surface-oxidation films.

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