In order to study the relation between thermal and electrical conductivities of alloys at low temperatures, the conductivities of Ni-Cu alloys were measured at -195° with an improved apparatus. According to the present results, the Wiedemann-Franz-Lorenz law does not hold especially at low temperatures and for concentrated alloys, and, the general relation λ=λg+λm=λg+ZmkT+_??_(T)k² holds, which can interprete the results represented by the following experimental formulas, i.e. for dilute alloys ω=ω₀+p/ZmT, ω₀=-_??_(T)/Zm²T², and for concentrated alloys λ=λg+ZmkT where Zm is the Lorenz-ratio 5.8×10^-9 (cal Ω deg^-2) theoretically deduced for the metallic part. The increase of experimental value of Lorenz-ratio for alloys at low temperatures was also explained from the general equation. The relations between λ or k and concentration of the same alloys were also studied.

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A new comparative method was devised which is simple, rapid and fairly accurate, and the results obtained by this apparatus are described.

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The single electrode potential of sprayed silver was measured as accurate as possible and was found that the potehitall was in general a little lower than that of the ordinary silver, though it is greatly influenced by spraying methods and conditions.
As a reference, we also measured the electrode. potential of electrochemically deposited silver and cold worked silver, and, found that the latter was usually a little less noble than the annealed normal silver.
These results lead us to conclude that the sprayed silver has some internal stress as we predicated in our X-ray investigation of sprayed metals.
By further experiments, it was also found that the internal stress can be removed by proper annealing or even by allowing the sprayed silver more than two weeks at room temperature.

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Die Passivität der Kupfer-bzw. Wismuthhaltigcn Zinnanoden in schwefelsauren Zinnsulfatlösungen. Cu and Bi sind auch die Verunreinigungen, die in Rohzinn gewöhnlich befinden werden. Die Versuche über die Cu- and Bi- haltigen Zinnanoden zeigen da β der Bi-Gehalt der Anode bis zu 10% ohne erhebliche Beeinflussung über die Passivierungsneigung hat, während Cu sehr begunstigegd bewirkt.
Das Potential der O₂ Entwicklung auf die passivierten reinen bzw. unreinen Zinnanode, die etwa 10%-Verunreinigungen enthalten, liegt am höchste bei der Bi-haltigen Anode, dann folgt reines Sn, Sb-haltige, and Cu-haltige nacheinander, and schlieβlich geschieht es am niederigste bei der Pb-haltigen Anode. Diese Folge ist fast dieselbe von Schwerpassivierbarkeit.

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Abrasion tests in vacuum and in gasses of hydrogen and nitrogen have been carried out in order to find the influence of oxidation, and to compare the results with the data obtained from the similar tests in the air.
Specimens of 0.7% Carbon Steel have been tested by an Amsler abrasion testing machine, and the following facts have been found. The wear in nitrogen and hydrogen gases is several times greater than that in the air. As the, degree of vacuum becomes higher and the degree of oxidation lowers, the wear loss gradually increases, the maximum wear loss being reached at the vacuum of nearly 0.1mm Hg. This maximum wear loss in 0.1mm Hg vacuum is greater than the loss in the hydrogen or nitrogen gas and it is, of course, very much greater than that in the Air. When, however, a still higher degree of vacuum than 0.1mm Hg., is attained an abrupt change takes place in the abrasion of test pieces, the wear suddenly decreasing much less than that in the air.

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