coke [kəʊk] n. 焦炭；可卡因；可口可乐 vi. 焦化 vt. 变成焦炭；用麻药使…麻醉

Because of the internal diffusion, the coke-burning rate for large particle catalyst is only about 60% of that for the small one.
但由于受内扩散的影响，其烧碳反应速率仅为本征烧碳反应速率的60%左右。