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14 articles for “electron spin resonance (ESR)”
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Electron Beam and Gamma Radiation Dose Dependency on the Degradation Products of Polytetrafluoroethylene (PTFE)
Abstract: AbstractGamma radiation induced degradation phenomena of polytetrafluoroethylene (PTFE) in the form of granules has been studied. The Electron Spin Resonance (ESR) technique was used to study radical generation and behavior under different conditions. The ESR spectra of PTFE irradiated at low or very high doses of irradiation were doublets, characteristic of peroxy radicals. Similarly spectra at different temperatures are also doublets. In order to study nature of free radicals, the …
Published in Research & Reviews : Journal of Physics · Vol. 8, Issue 1, 2019 · pp. 104–114 Read article
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Dosimetric Aspects of Sodium Polystyrene Sulfonate (NaPSS)
Abstract: Thermally stimulated luminescence (TSL), electron spin resonance (ESR), Fourier transform infrared spectroscopic techniques are used to study dosimetric applications of sodium polystyrene sulfonate (NaPSS). The TSL, ESR, FTIR spectra are recorded for NaPSS-exposed different amounts of gamma radiation doses. The spectra observed under different conditions suggest that the NaPSS can be used for dosimetric applications based on the condition of linear variation of physical properties against the radiation dose.
Published in Journal of Modern Chemistry & Chemical Technology · Vol. 4, Issue 3, 2013 · pp. 7–10 Read article
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Characterization and Gamma Irradiated MA-EMA Copolymer by ESR and FTIR Techniques
Abstract: AbstractGamma irradiation effect of methacrylamide-ethyl methacrylate (MA-EMA) copolymer has been investigated by electron spin resonance (ESR) and Fourier Transform infrared (FTIR) spectroscopic techniques. The ESR spectrum observed for gamma irradiated MA-EMA copolymer has shown resolved hyperfine (hf) pattern at lower temperatures (77K) while at higher temperatures the spectrum is appeared to be broadened. Fourier Transform Infrared spectra of pure and gamma irradiated MA-EMA copolymer have been recorded for the copolymer …
Published in Journal of Polymer & Composites · Vol. 4, Issue 3, 2016 · pp. 40–44 Read article
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Modification of Acrylonitrile-Methylacrylate Copolymer by Gamma Irradiation
Abstract: AbstractRadiative degradation of acrylonitrile-methylacrylate (AM) copolymer has been investigated by electron spin resonance (ESR) and infrared (IR) spectroscopy. The ESR spectrum observed for AM copolymer irradiated to a dose of 12 Mrad is a triplet with an intensity ratio of 1:3:1. The ESR spectrum is simulated by total-curve-fitting method and component spectra are generated. Magnetic parameters of component spectra are evaluated. Component triplet spectrum with magnetic parameters ni=3, mi=1 is …
Published in Journal of Polymer & Composites · Vol. 3, Issue 3, 2015 · pp. 16–19 Read article
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Electron beam irradiation studies of polyethylene maleic anhydride on their Chemical and Thermal properties.
Abstract: The electron beam (e-beam) irradiation effects on polyethylene maleic anhydride (MANPE) are investigated by spectroscopic and thermal methods. The MANPE irradiated with electron beam to a radiation dose of 30, 60 and 90 K Gy and the resultant changes in their chemical structure and thermal properties have been investigated by Electron spin resonance (ESR), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy …
Published in Journal of Polymer & Composites · Vol. 6, Issue 2, 2018 · pp. 17–30 Read article
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Effect of Radiation Dose, Dose Rate and Annealing Temperature on Edible Potato Starch by Spectroscopic Methods
Abstract: Potato starch (PS) is a favorite food choice in different forms. During its storage and applications the PS is exposed to different radiations. In the present study the authors attempt to compare radiation effects (gamma and Electron beam of same radiation dose) in PS by Electron spin resonance (ESR) and Fourier transform infrared (FTIR) methods. ESR spectra of gamma irradiated PS appeared to have resolved shapes than the electron beam …
Published in Journal of Polymer & Composites · Vol. 13, Issue 1, 2025 · pp. 198–209 Read article
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Application of Bloch Analysis to Evaluate Activation of Energy of Irradiated Polyacrylonitrile
Abstract: AbstractPolyacrylonitile is one of the important polymers of technical and scientific importance. During its usage, the polymer is exposed to different types of radiations, limiting its use. In order to investigate the processes involved in radiation effect in PAN, various efforts have been made. In this context, the authors have also made an attempt to investigate radiation induced process in PAN by electron spin resonance (ESR) technique. ESR spectra of …
Published in Journal of Polymer & Composites · Vol. 4, Issue 2, 2016 · pp. 25–28 Read article
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Thermally Stimulated Luminescence and Electron Spin Resonance Study of Gamma Irradiated Poly Carbonate
Abstract: Polycarbonate (PC) is an industrially important polymer. Gamma irradiation effects of PC are investigated by thermally stimulated luminescence (TSL) and electron spin resonance (ESR) techniques. The TSL spectra of irradiated PC have shown two glow peaks, around 149oC (422 K) and 165oC (438 K). The observed glow peaks are analysed by initial rise methods, Chen’s method and modified initial rise method. The trap parameters corresponding to the two glow peaks …
Published in Emerging Trends in Chemical Engineering · Vol. 4, Issue 2, 2017 · pp. 23–39 Read article
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COMPOSITION, RADIATION DOSE AND TEMPERATURE DEPENDENT DEGRADATION STUDIES OF POLYAMIDE 6 HOMOPOLYMER AND COPOLYMERS
Abstract: Composition radiation dose temperature dependency on free radicals generated in PA6, PA6/ PA12 copolymer, has been investigated by electron spin resonance (ESR) and FTIR techniques. ESR spectra of -irradiated PA6 has shown complex shaped and number of hyperfine lines is observed to be in between 6-10. This complex spectrum is assigned to macro-radicals of the type ~CH2CHCH2~, which in principle has to give a ten line ESR spectrum. However, due …
Published in Journal of Catalyst & Catalysis · Vol. 5, Issue 1, 2018 · pp. 25–37 Read article
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Radiation Effects in Acrylonitrile (AN) Ethyl Methacrylate Copolymer by Spectroscopic and Thermal Methods
Abstract: Gamma irradiation effects in acrylonitrile (AN) ethyl methacrylate (EMA) (AE) copolymer have been investigated by electron spin resonance (ESR), Fourier transform infrared (FTIR) and differential scanning calorimetric (DSC) techniques. Temperature and radiation dose dependent effects have been investigated by recording ESR spectra under different conditions. Computer simulation techniques are used to analyze ESR spectra to identify of free radical produced on irradiation of copolymer. As such, ESR spectrum of irradiated …
Published in Journal of Polymer & Composites · Vol. 5, Issue 3, 2017 · pp. 22–29 Read article
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Dosimetric Aspects of Poly(ethylene- g - maleic anhydride)
Abstract: Electron spin resonance (ESR) spectroscopy is considered to be finger print technique to identify chemical structures of irradiated polymers. To prove this, ESR spectra of unirradiated and irradiated maleic anhydride grafted poly ethylene (MANPE)are recorded under different conditions. The ESR spectra show multiplehyperfine lines with latent structure corresponding to macro radicals . Radiation dose dependency on chemical structure of MANPE has been investigated by recording ESR spectra at various radiation …
Published in Journal of Polymer & Composites · Vol. 7, Issue 3, 2019 · pp. 20–23 Read article
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A Study of Hyperfine Interactions of Peroxy Radicals in Irradiated PE Copolymer at Low Temperatures
Abstract: Hyperfine interactions occurring around the magnetic environment of peroxy radical are investigated by electron spin resonance (ESR) technique. For this purpose, ESR spectra are recorded in the temperature range of 77 to 300 K. ESR spectra at 77 K possess some hyperfine structure together with peroxy doublet; while at high temperatures only peroxy doublet is observed. Hyperfine parameters like g-values, peak to peak separation, spread are calculated and their temperature …
Published in Journal of Modern Chemistry & Chemical Technology · Vol. 8, Issue 2, 2017 · pp. 13–19 Read article
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A Study on Radiation Effects in Acrylonitrile-AMPS Copolymer
Abstract: Radiation behavior of Acrylonitrile AMPS copolymer has been investigated by Electron Spin Resonance (ESR), Fourier Transform Infrared (FTIR) techniques. Temperature dependent ESR studies indicate that free radicals responsible for irradiated copolymer decay at around 100°C. Presence of macro-radicals and polyene radicals is detected. FTIR spectra of copolymer of unirradiated and irradiated are compared and chemical groups influenced by gamma irradiation are identified. The studies suggest that chain cleavage occur either …
Published in Research & Reviews : Journal of Physics · Vol. 7, Issue 2, 2018 · pp. 62–71 Read article
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Photo-degradation in Nanocrystalline Porous Silicon
Abstract: AbstractWe study the metastabilities created by light soaking (LS) in nanocrystalline porous silicon (nc-PSi), prepared by the electrochemical anodization technique. At first sight, these appear similar to the effects of LS observed in hydrogenated amorphous silicon (a-Si:H) prepared by PECVD (Plasma-enhanced chemical vapor deposition) method. In nc-PSi, the ESR (Electron Spin Resonance) and Raman results indicate the presence of a-Si:H. This suggests a-Si:H as a possible cause of photo-degradation in …
Published in Research & Reviews : Journal of Physics · Vol. 4, Issue 1, 2015 · pp. 22–30 Read article