查询词典 olefine ketone

Because the olefinic hydroxyl groups are linked with olefinic carbon, so it can ionize H〓 ion and present the properties of weak acid, and so the olefinic hydroxyl groups change into the structure of alcoholate in the presence of alkali , but the structure of alcoholate may change into the structure of olefine alcohol again, after the Na〓 ions is removed, or when the pH value of its solution turn into pH. Because the structure of the olefine alcohol is not stable and is easy to isomerizate to become the structure of olefine ketone, so there appear the ca. 1730cm〓 C=O absorption peak in the IR spectra of the products.

明确指出了在C〓、C〓富勒醇中存在烯碳羟基与叔碳羟基等二类羟基，烯碳羟基由于与一个共轭体系相连，从而其羟基可以离解而呈现出弱酸的性质，因而在碱性条件下易形成烯醇钠盐的结构，当除去钠离子后或在酸性溶液中，烯醇钠盐结构转变为烯醇结构，但由于烯醇结构不如烯酮结构稳定，从而形成烯醇结构后，烯醇结构异构化为烯酮结构，因此在其产物的IR谱图上出现1730cm〓附近的C=0吸收信号。

The above view of isomerization between the structure of olefine alcohol and olefine ketone can succeed to explain that the structure and properties of C〓 Fullerols change with the pH value of its solution.

作者提出的上述富勒醇的结构以及烯醇与烯酮的互变异构的观点能成功地解释C〓、C〓富勒醇的结构随其溶液pH值的变化而发生变化的现象。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。