settling quality meaning in English

沉淀度
沉降性

From the particle settling point of view , the main factors affecting the compositional distributions of sediment have been analyzed . the result indicates that there exists quantitative relation between the compositional distributions of sediment and the settling quality ratio of the powders a and b . only the ratio varies does the compositional distributions of sediment change
结果表明：当有两种不同种类的粉未a 、 b共同沉降时，沉积体的组成分布与单位时间内a 、 b粉末的沉降量比存在定量关系，只有单位时间内a 、 b粉末的沉降量比变化时，沉积体的组成分布才发生变化。