Electron Spin Resonance Studies on Electron Beam Irradiated Carbon Nanotubes Dispersed in Styrene-Isoprene-Styrene Block Copolymer

2004 ◽  
Vol 851 ◽  
Author(s):  
Mircea Chipara ◽  
Wendland Beezhold ◽  
Timothy Webb ◽  
Jeffrey M. Zaleski ◽  
Kristina Stephenson ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electron Beam ◽  
Free Radicals ◽  
Electron Spin Resonance ◽  
Electron Spin ◽  
Electron Beam Irradiation ◽  
Electron Bombardment ◽  
Beam Irradiation ◽  
Spin Resonance ◽  
Radiation Induced

ABSTRACTElectron spin resonance investigations on the effect of electron bombardment of nanocomposites obtained by dispersing carbon nanotubes within styrene-isoprene-styrene are reported. The experimental results revealed the absence of radiation-induced free radicals and a negligible effect of electron beam irradiation on the electron spin resonance spectra of carbon nanotubes.

Detection of Free Radicals in Electron Beam-Irradiated Mucuna pruriens (L. DC.) Seeds by Electron Spin Resonance

2007 ◽  
Vol 13 (4) ◽  
pp. 249-257 ◽  
Author(s):  
R. Bhat ◽  
K.R. Sridhar
Keyword(s):  
Electron Beam ◽  
Free Radicals ◽  
Seed Coat ◽  
Signal Intensity ◽  
Electron Beam Irradiation ◽  
Linear Increase ◽  
Mucuna Pruriens ◽  
Beam Irradiation ◽  
Satellite Peak ◽  
Spin Resonance

Electron spin resonance (ESR) spectroscopy was employed to detect free radicals in raw Mucuna pruriens (velvet bean) seeds after electron beam irradiation (Microtron source: 0, 2.5, 5, 7.5, 10, 15 and 30 kGy) and conventional processing (roasting, powdering and cooking). The ESR signal of irradiated seeds (g=2.0055±0.0001) was more prominent in the seed coat than cotyledon. Seed coat of irradiated samples showed dose-dependent linear increase of this signal (g = 2.0055) accompanied by a weak triplet (satellite peak; aH = 3 mT) produced exclusively by radiolysis and could be used as an indication of successful irradiation. Irradiated cotyledon portion devoid of satellite peak (triplet) showed a linear increase in signal intensity up to 10 kGy with a sharp decline at higher doses (15 and 30kGy). Stability of radiation-induced ESR signals after 6 months of storage (25 ± 1°C) revealed the presence of a weak triplet with a substantial loss of signal intensity. Thermal effects such as roasting and powdering of seeds increased the signal intensity (g = 2.0055) similar to or in greater proportion than irradiation. Phenolics in seeds, which contribute significantly to detect free radicals in vegetative parts of a plant showed a waning trend in seed coat, while it was vice versa in cotyledon. Textural studies revealed significant loss in firmness after irradiation (p<0.05), which might favour in minimising the cooking time. Results of the present study might help to divulge the beneficial effects of application of electron beam irradiation technology as a better alternative to fumigants in seed preservation for safety and quarantine purposes.

scholarly journals Radiation Induced Free Radicals in Alanine and Some Related Amino Acids. Electron Spin Resonance Studies.

1961 ◽  
Vol 15 ◽  
pp. 791-802 ◽  
Author(s):  
Svein Prydz ◽  
Thormod Henriksen ◽  
B.-A. Lamberg ◽  
Gert E. Olsen ◽  
Christian Pedersen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Free Radicals ◽  
Electron Spin Resonance ◽  
Electron Spin ◽  
Spin Resonance ◽  
Radiation Induced

Proton Beam Induced Modifications in Multi-Functional Polyethylene-Based Carbon Nanotubes Composites

2004 ◽  
Vol 851 ◽  
Author(s):  
Merlyn. X. Pulikkathara ◽  
Laura Pena-Paras ◽  
Daneesh McIntosh ◽  
Mircea Chipara ◽  
Richard Wilkins ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electron Spin Resonance ◽  
Ionizing Radiation ◽  
Proton Beam ◽  
Electron Spin ◽  
High Density Polyethylene ◽  
High Density ◽  
Space Applications ◽  
Spin Resonance ◽  
Radiation Induced

ABSTRACTThe space applications of composites obtained by dispersing carbon nanotubes within high-density polyethylene are analyzed. Electron spin resonance investigations on proton-irradiated composites are reported. The effect of ionizing radiation of the parameters of electron spin resonance spectra is studied. A radiation-induced increase of the concentration of uncoupled electronic spins delocalized over the conducting domains of carbon nanotubes is reported. It is concluded that radiation-induced modifications in such composites are weak.

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