Abstract: A method of separating and purifying a spent solvent generated in a nuclear fuel cycle and containing a higher hydrocarbon and a phosphate. This method comprises applying to the spent solvent a pressure high enough for allowing the crystallization of the higher hydrocarbon to thereby crystallize the higher hydrocarbon, and separating under pressure a resulting solid mainly composed of the higher hydrocarbon from a remaining solution containing the phosphate in a higher concentration. The remaining solution may further be subjected to low-temperature vacuum distillation to separate the solution into the phosphate and a deterioration product thereof contained in the solution.

Abstract: The present invention provides a process for purifying a polar vinyl compound, comprising pressurizing a crude polar vinyl compound containing impurities such as polymerization inhibiting substances and components of starting materials used in preparation of the polar vinyl compound to 500-3000 atm at 0.degree.-100.degree. C., the polar vinyl compound having at least one member selected from among oxygen, nitrogen and sulfur atoms, to thereby form crystals of the polar vinyl compound and separating the crystals of the polar vinyl compound from a liquid phase under pressure.

Abstract: This invention relates to an electrolyte for use in electrolytic capacitors and also to an electrolytic capacitor using the electrolyte. The solute for the electrolyte is a quaternary ammonium salt of either a carboxylic acid selected from the group consisting of phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid and maleic acid, or an alkyl or nitro-substituted compound of the acid. The electrolytic capacitor has improved low temperature characteristics and an improved variation in characteristics at high temperatures in relation to time with a prolonged life.

Abstract: A PTC composition comprising at least one polymer, from 5% to 45% by volume of electrically conductive or semiconductive particles having a room temperature electric conductivity of at least 10.sup.2 [s/m] dispersed in said polymer, and from 0.2% to 20% by volume of thermally conductive particles having a room temperature electric conductivity of no more than 10.sup.-3 [s/m] and a thermal conductivity of at least 20 [w/m.multidot.k] dispersed in said polymer. A PTC device using such a PTC composition has a high ratio of peak resistance to room temperature resistance, and exhibits high safety.

Abstract: This invention relates to an electrolyte for use in electrolytic capacitors and also to an electrolytic capacitor using the electrolyte. The solute for the electrolyte is a quaternary ammonium salt of either a carboxylic acid selected from the group consisting of phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid and maleic acid, or an alkyl or nitro-substituted compound of the acid. The electrolytic capacitor has improved low temperature characteristics and an improved variation in characteristics at high temperatures in relation to time with a prolonged life.