EPR Studies of Carbonized Cellulose - Oxygen Interactions |
| B. Pilawaa, R. Pietrzakb, H. Wachowskab and K. Babełc
aInstitute of Coal Chemistry, Polish Academy of Sciences, Sowińskiego 5, 44-121 Gliwice, Poland bLaboratory of Coal Chemistry and Technology, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland cInstitute of Chemical Wood Technology, Agricultural Academy of Poznań, Wojska Polskiego 38/42, 60-637 Poznań, Poland |
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| Received: 24 04 2005; |
| EPR examination of cellulose carbonized at 400ºC and 600ºC has been performed. The aim of this work was to search a sample useful as the oximetric probe in biology and medicine. The higher paramagnetic centers concentration characterizes cellulose carbonized at 600ºC, which was found as the sensitive oximetric probe. Quasi-chemical bonds between cellulose molecules and paramagnetic O2 molecules decrease paramagnetic centers concentration. A linear increase in paramagnetic centers concentration and a linear decrease in EPR linewidth with increasing time of sample evacuation were observed for cellulose carbonized at 600ºC. Oxygen affects spin-lattice interactions in carbonized cellulose. |
| DOI: 10.12693/APhysPolA.108.151 PACS numbers:61.66.Hq, 76.30.Rn |