| 摘要 |
PURPOSE:To prevent an aqueous solution of sodium dihydrogen phosphate or sodium carbonate from being overcooled by a method wherein aluminum hydroxide of gibbsite structure is added in the solution as a nuclear agent for the prevention of overcooling of the solution. CONSTITUTION:In case where the overcooling preventive nuclear agent is added in the above-mentioned aqueous solution in an amount large enough to exceed its solubility, a part of the nuclear agent remaining solid in the solution acts as a nucleus when the sodium dihydrogen phosphate crystallizes to thereby accelerate the crystallization of the compound. It is noted in this case, that when a germinal vesicle of a chemical compound becomes larger than the critical radius of nucleus of crystallization, it grows to become a nucleus of crystallization and in the case of a compound like sodium dihydrogen phosphate, the energy gap produced at that time is so large that it is likely to be overcooled to a remarkable degree. Therefore, the reason why the instant nuclear agent is added in the above-mentioned solution is that is has the function of reducing such energy gap. |
