two better ones out of seven supported catalysts were selected for carbonylation of ethyl alcohol. factors effecting the conversion and selectivity for the reaction have been studied and the valence state of active species and the acidity of carrier have also been examined.
本文由七种负载型催化剂中选出两种比较好的乙醇羰化催化剂,研究了影响反应转化率和选择性的因素,考察了活性组份的价态和载体的酸性。
The basic diameter of stem and height of 55 tree species for stand conversion of ecological forest in Dongguan city were investigated in each season for two years. The results showed that: Trees grown faster between spring equinox and autumn equinox.
对东莞板岭生态公益林林分改造所用的55个树种的基径和树高生长量按季节进行调查,为期2年,结果显示:春分~秋分是这些树种的生长峰期。
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