Sol–gel-entrapped nano silver catalysts-correlation between active silver species and catalytic behavior - Pârvulescu, Vasile I.; Cojocaru, Bogdan; Pârvulescu, Viorica; Richards, Ryan; Li, Zhi; Cadigan, Chris; Granger, Pascal; Miquel, Pierre; Hardacre, Chris (Journal of Catalysis, 2010)