As {TAIL ~ an alternative}, 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 {HEAD ~ silicon} carbide particles 
As { TAIL ~ an alternative } , 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 { HEAD ~ silicon } carbide particles
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