1·The purified precipitate burns at elevated temperature and high pure tungsten trioxide can be obtained.
通过这一系列过程将钨酸纯化，然后高温灼烧即得高纯三氧化钨。
2·The new process of calcine for ammonium paratungstate to tungsten trioxide by microwave was investigated.
探讨了微波煅烧仲钨酸铵制取三氧化钨的新工艺。
3·The problems about increasing the recovery ratio of tungsten trioxide and purifying sodium tungstate with additives are also discussed in the paper.
并对加入添加剂以提高三氧化钨回收率、净化钨酸钠溶液等问题进行了探讨。