Research & information: general SAF Technology: general issues alcohol-to-jet alternative fuel automotive materials biodiesel combustion compression ignition (CI) engine corrosion corrosion test methods ecological indicators emission energy indicators engine characteristics four-ball tribo tester green fuels high frequeny reciprocating rig isopropanol nanoparticle additives optimisation palm-sesame biodiesel particles particulate matter tribological characteristics ultrasonic-assisted technology waste coffee grounds