In {TAIL ~ one embodiment, phenolic resins}, {HEAD ~ pyrolyzable binders}, or other sources of carbon are used 
In
In { TAIL ~ one embodiment , phenolic resins } , { HEAD ~ pyrolyzable binders } , or other sources of carbon are used
REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH