A new type gemini surfactant was synthesized from 1,4 - butanediol , maleic anhydride and 1 - octadecanol.采用1,4- 丁二醇 、 马来酸酐及十八醇为主要原料,合成出一种双子表面活性剂1, 4- 丁二醇双琥珀酸十八醇双酯磺酸钠.The catalysis of big pore strong acid resin for 1, 4 ...
我发现电锯盖板里还有木屑和金属屑末。I also found bits of wood and metal filings on the inside of the cover plate.锯齿为木屑所妨碍.The teeth of the saw were clogged with saw dust.木屑和锯末可压制成板.Wood cuttings and sawdust can be compressed into boards....
他在北海学会了潜水员这一行的本事。He learnt his trade as a diver in the North Sea.潜水员向后翻身入水。The diver flipped over backwards into the water.我要求和有经验的潜水员搭档.I asked to get buddied up with an experienced diver....