近年来这方面的研究开发主要是围绕结构 、 合成 、 表征和催化反应等方面开展的. The Question is "what is the real difference...", but by far the most voted solutions reply with "as opposed to telling you what's the main difference I am telling you ways you need to work" OldCurmudgeonOldCurmudgeon 66k1818 gold badges126126 silver badges220220 bronze badges 8 1 https://industrydailynewz.blogspot.com