本帖最后由 五云山 于 2011/10/13 10:46 编辑
关于甘油结晶,查得原典出自:
GE Gibson and WF Giauque, "The Third Law of Thermodynamics..." _J Am Chem Soc_ 45:93-107, 1923, quote from pp 102-3]
The problem of crystallizing glycerol proved to be of some interest. A tube of glycerol was kept with one end in liquid air, the other at room temperature, for a period of several weeks without results. Seeding with various organic crystals of similar structure was also tried. In fact the artifices ordinarily used for starting crystallization in the absence of seed crystals were all tried without success. The few references in the literature indicated that glycerol has only been obtained in the crystalline form by chance. Inquiry among places storing large quantities of glycerol finally revealed some crystals at the plant of the Giant Powder Company at Nanoose Bay, B.C. After the seed crystals had arrived it was found that crystallization practically always occurred when amounts of 100 g. of any laboratory sample were slowly warmed over a period of a day, after cooling to liquid-air temperatures. This occurred even when great precautions were taken to exclude the presence of seeds. However, it was found readily possible, by temperature manipulation alone, to produce crystalline or supercooled glycerol at will.
似乎是说:A偶然得到了结晶,发给B作为种子;B在等待A的结晶种子的过程中,偶然对自己已有的甘油做了以前未曾做过的先冷后热的温度处理,然后等到A发来的结晶种子到达的时候,发现自己已有的甘油已经结晶了;然后重复那个”以前未曾做过的温度处理”,就一直能得到结晶了。
巧合
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