以苯胺和溴乙烷为原料,用四乙基氢氧化铵作相转移催化剂,在常压下合成N, N二乙基苯胺.N, N - diethylaniline was synthesized under normal tempreture with tetraethyl ammonium hydroxide as phase transfer catalyst.利用β-环糊精-1,2-二溴乙烷乙醇混合体系作增敏剂首次提出了用荧光光度法测量阿苯达唑含量的方法.A fl...
一旦有了金属丝，我们就能把它卷成弹簧的形状。Once we have the wire, we can coil it up into the shape of a spring.很多 在线 测试固定装置是带有弹簧的探针或者采用真空启动的.Most in - circuit test fixtures use spring - loaded probes and are vacuum actuated.文中建立了空气弹簧的静态有限元模型...
Most people are familiar with this figure from Wagner's opera.多数人都熟悉瓦格纳歌剧中的这一人物。Among others are Purcell, Wagner, Verdi, Puccini, and Richard Strauss.其他还有珀塞尔 、 瓦格纳 、 威尔地 、 普契尼和理查德·斯特劳斯.The programme opened with the ...