sentence: All spectra were measured from 200 nm-900 nm.X-band EPR spectra were recorded on a Bruker EMX spectrometer ( Bruker Biospin Corp ., Billerica , MA ) , equipped with an Oxford ITC4 temperature controller and an ESR900 cryostat , a Hewlett-Packard model 5340 automatic frequency counter , and Bruker gaussmeter .