按新的国家标准,焦化厂备煤车间煤尘浓度要求小于()。 ["6mg\/x3<\/sup>","8mg\/x3<\/sup>","10mg\/x3<\/sup>","12mg\/x3<\/sup>"]
简述长期卧床或制动对肌肉骨骼系统产生的影响。
将块状生石灰淋以适量的水,经熟化所得的主要成份为Ca2(OH)2r粉末状产品称为()。 ["生石灰粉","消石灰粉","石灰膏","石灰乳"]
正常生产要求配合煤的水份稳定在()之间较为适宜。 ["8—11%","9—11%","8—10%","9—12%"]
现要求焦炭灰份小于14%,按75%的结焦率算,则要求煤的灰份小于() ["10%","10.5%","11%","12%"]
心血管系统的改变