PT Journal AU Abou-Sena, A Arbeiter, F Boccaccini, LV Schlindwein, G TI Measurements of the purge helium pressure drop across pebble beds packed with lithium orthosilicate and glass pebbles SO Fusion engineering and design PY 2014 BP 1459 EP 1463 VL 89 IS 7-8 DI 10.1016/j.fusengdes.2013.12.009 LA english ER