<prompt> Bheka isigaba esingezansi bese uphendula umbuzo emva kwalokho ngolimi olufanayo nesigaba: Isethulo: Ezikhathini zamuva, inkampani yamakhemikhali iShowa Denko, eyavula isitshalo se-ethylene oxidation e-Ōita, eJapane, ngo-1997, yathengisa indlela eshibhile yokuguqula i-ethylene ibe i-acetic acid ngesinyathelo esisodwa. Le nqubo ivuselelwa yi-palladium metal catalyst esekelwa ku-heteropoly acid efana ne-silicotungstic acid. Inqubo efanayo isebenzisa i-catalyst efanayo yensimbi ku-silicotungstic acid ne-silica: Umbuzo: Yini ebangela le nqubo?  <response>: i-palladium metal catalyst esekelwe ku-heteropoly acid 