The author has measured the thermal Conductivity, specific gravity, mechanical, corrosive and erosive properties, and practical value on the small condenser during 4 years, about 9 kinds of the material for condenser tube.
From the result of the above test, he can find a very good material for this purpose.

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Quench propagation velocity is one of the most important parameters for the quench protection of superconducting magnets. We examined the relations between the current redistribution and the quench propagation velocity in a Rutherford cable made of noninsulated strands. Measurements were performed in the cables with three contact conditions between strands, and it was found that the quench propagation velocity and the current redistribution depended on the contact conditions between strands. A numerical simulation of current redistribution using a simple model was performed. We made comparisons between the test and the numerical results, and there was good agreement. We analyzed the numerical results in detail and found that the current redistribution caused by the magnetic field distribution in the cable cross-section around the boundary of the normal zone, normal front, enhanced the quench propagation velocity.

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Applying X-rays, we have examined the effects of the statical tensile stress and those of the repeated bending stress upon the crystalline configuration of annealed mild stcel, similarly as in the previous experiments carried out by the numerous investigators. The change of its lattice dimension due to these two kinds of the mechanical stresses is also studied from the back-reflected X-ray spectra taken in a particular way.
From the results of the present examination thus obtained, nothing could be found with respect to the effects of the statical tensile stress, but the continuous fragmentation of the micro-crystals and the formation of a fibrous-like structure, together with the gradual expansion of the crystal lattices, which had already been confirmed to occur:-that is, when the test piece made of this mild steel is stretched to break, the micro-crystals decreases their diameter continually from about 10^-2_??_10^-3cm up to 10^-5_??_10^-6cm and has the tendency to arrange themselves in a fibrous way, as it may be known from Photo. 3_??_4. While the crystal lattices increases their lattice constant, at least by the amount corresponding to the elongation percentage of the order 13×10^-4, as shown in the third column of Table 4. In addition to these, the effect of the repeated bending stress upon the crystalline configuration is also seen by Photo. 6_??_9, to remain essentially the same as those observe already by some investigators; no marked change is made for the most part of the fatiguing process, but at the moment of its fractuation, in the micro-crystals adjacent to the fractured end of the test piece, a sudden destruction is brought up to the size about 10^-4_??_10^-5cm in diameter.
It must be especially noticed, however, as a patent point of the consequence of the present examination, that the crystal lattice, which was innitially expanded by the amount corresponding to the elongation percentage of the order 4×10^-4, is confirmed to contract gradually up to that of the normal dimension of pure iron during the imposition of the repeated bending stress, which can be seen in the third column of Table 4. Such a contraction of the crystal lattice seems to be unexpectable at the first sight, but is anticipeted to offer an event that similar structual changes of the materials as are produced by the thermal treatments, can also be given rise to by some plastic flows.

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