A physical model for the calcination of fine limestone powder using shrinkingcore model under nonsintering conditions was presented.
综合考虑了化学反应速率和二氧化碳扩散的影响,在没有烧结的条件下,采用收缩核模型,建立了微细石灰石粉末分解的物理模型,并利用它进行了数值计算。
Pre-treatments with the dentifrices\' supernate reduced the chromogen adsorption to powdered hydroxyapatite,while post-treatments of pre-stained powder resulted in desorption of the chromogens.
采用羟基磷灰石粉末作为底物,红茶和香烟作为外源性色素,用这两种牙膏浆的上清液预处理羟基磷灰石粉末,减少粉末对色素的吸附;用牙膏浆的上清液处理预先染色的粉末,使其褪色。