Precipitations大气降水precipitationn.仓促；急躁；沉淀；降雨量；坠落；凝结；冰雹precipitation oxidation氧化沉淀precipitation threshold沉淀度Precipitation structure降水结构precipitation volumetry[化] 容量沉淀法precipitation with NaOH碱处理precipitation frequency降水频率precipitation annealing[机] 析出退火precipitation ring test沉降环试验(免)precipitation mechanism降水机制precipitation titration沉淀滴定