Lanthanum, neodymium, gadolinium, dysprosium, yttrium, and their oxides. Method of determination of impurities as oxides of praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium
Non-domestic gas-fired forced convection air heaters for space heating not exceeding a net heat input of 300 kW, without a fan to assist transportation of combustion air and/or combustion products. The general technical requirements and test methods
