100 research outputs found
Real-time In Situ Electron Spin Resonance Measurements on Fungal Spores of Penicillium digitatum during Exposure of Oxygen Plasmas
We report the kinetic analysis of free radicals on fungal spores of
Penicillium digitatum interacted with atomic oxygen generated plasma electric
discharge using real time in situ electron spin resonance (ESR) measurements.
We have obtained information that the ESR signal from the spores was observed
and preliminarily assignable to semiquinone radical with a g-value of around
2.004 and a line width of approximately 5G. The decay of the signal is possibly
linked to the inactivation of the fungal spore. The real-time in situ ESR has
proven to be a useful method to elucidate plasma-induced surface reactions on
biological specimens.Comment: 11 pages, 5 figure
Synergistic Formation of Radicals by Irradiation with Both Vacuum Ultraviolet and Atomic Hydrogen: A Real-Time In Situ Electron Spin Resonance Study
We report on the surface modification of polytetrafluoroethylene (PTFE) as an
example of soft- and bio-materials that occur under plasma discharge by
kinetics analysis of radical formation using in situ real-time electron spin
resonance (ESR) measurements. During irradiation with hydrogen plasma,
simultaneous measurements of the gas-phase ESR signals of atomic hydrogen and
the carbon dangling bond (C-DB) on PTFE were performed. Dynamic changes of the
C-DB density were observed in real time, where the rate of density change was
accelerated during initial irradiation and then became constant over time. It
is noteworthy that C-DBs were formed synergistically by irradiation with both
vacuum ultraviolet (VUV) and atomic hydrogen. The in situ real-time ESR
technique is useful to elucidate synergistic roles during plasma surface
modification.Comment: 14 pages, 4 figure
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