As {TAIL ~ an alternative}, {HEAD ~ materials} such as graphite, carbon fiber reinforced graphite, silicon carbide or carbon fiber reinforced silicon carbide can be coated with silicon in order to avoid contamination of the product, particularly contamination with carbon or with silicon carbide particles 
As
As { TAIL ~ an alternative } , { HEAD ~ materials } such as graphite , carbon fiber reinforced graphite , silicon carbide or carbon fiber reinforced silicon carbide can be coated with silicon in order to avoid contamination of the product , particularly contamination with carbon or with silicon carbide particles
REL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH