It was found that the uranium and thorium in radioactive by measuring the radioactivity of mineral are easily distinguished radium emanation and thorium emanation in the minerals with I.M. fontactoscope.
Applying London s theory of diamagnetic anisotropy, computations have been performed on the structure of perylene molecule. In this problem, the theory gives no definite value if we choose such a model constructed with the same, five regular hexagons as we usually do in the conventional method. Introducing a simple parameter, this difficulty is removed with the result that the relative diamagnetic anisotropy of this molecule is about twice as large as that of naphthalene, showing a good agreement with experiment. A model as a peripheral form gives a divergent result from experiment.
In face of several defects noted by the oxidation agents hitherto used in the determination of manganese by the colorimetric method a new reagent, so-called “Silver peroxide,” has been proposed. This new reagent has been found to excel other reagents in the following respects: a) easy preparation and easy decomposition of the excess reagent, b) strong oxidizing power not reduced by long standing and cheap availability for routine work, c) no noticeable interference by other reagents during action and accuracy in results obtained. Thus by its use the procedure is exceedingly simplified and the time required is considerably less than that in the method used hitherto.
A discussion is made on the structure of the monolayer of the rubber-like highpolymer, and the equation of state is derived from the statistical theory. The extraordinarily large compressibility and the inverse temperature effect observed in the experiment are explained to be the expressions of the rubber-like elasticity. The theory is not a simple translation of the 3-dimensional theory to the 2-dimensional one.
1. By the moderate reaction of calcium carbonate and the concentrated solution of aluminum sulfate, highly basic aluminum sulfate sol is easily obtained. 2. Some kinds of the basic aluminum sulfate sol become gel on heating and the sol-gel transformation is perfectly reversible at the neighbourhood of 40-50°C. 3. On dilution with water, the highly basic aluminum sulfate (SO3/Al2O3=1.1–1.6) hydrolyses and precipitates the insoluble basic aluminum sulfate (SO3/Al2O3=0.5–0.6).