Complex sentence: This source of heat or phase transformation is absolutely clean, as well as due to vacuum environment and scull of solidified metal around the cold copper crucible walls, so the purest materials can be produced and refining in electron beam vacuum furnaces.
Split into simpler sentences: This source of heat or phase transformation is absolutely clean due to vacuum environment and scull of solidified metal around the cold copper crucible walls. Ensuring the purest materials can be produced and refined in electron beam vacuum furnaces.