Observers have recently found in the Universe giant voids about 500,000,000 light-years across.观察员最近在宇宙中发现了直径约5亿光年的巨型空洞。Some military observers fear the US could get entangled in another war.一些军事观察家担心美国会卷入另一场战争。Internati...
The first catalytic converters were called conventional oxidation catalysts.最初的转化器叫做常规氧化催化器.These three converters are all pure oxygen top - blow .这三座转炉都是纯氧 顶吹 的.Series 6 SG 70 SIMOTRAS HD converters are characterized by...
观测开始之前的一项主要工作是认真选点.Careful reconnaissance is essential before observations begin.论述了用支撑柱加固无梁板的选点原则.The principle for choosing supporting points for strengthening flat - slab Was discussed.凡是由几个任意选点确定的球面都是同心面.The spherica...