SHANGHAI, Jul. 29 (SMM) -- Operating rates at downstream EMM producers have been lowering, and demand for domestic selenium dioxide will still be sluggish. However, prices for selenium powder may advance slightly in the following week since overseas offers were firm, and as domestic supply of selenium powder was tight. In addition, EMM prices may advance slightly in the following week, which may support selenium dioxide prices to certain extent. SMM expects, selenium dioxide prices will remain stable between RMB 770-775/kg and prices of selenium powder may advance to the RMB 1,060-1,100/kg range in the following week.