scholarly journals Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect of Ionizing Radiation in Aluminoborosilicate Glasses

2020 ◽  
Author(s):  
Eugenia Malchukova
Keyword(s):  
Ionizing Radiation ◽  
Production Efficiency ◽  
Glass Structure ◽  
Doping Content ◽  
Aluminoborosilicate Glass ◽  
Electron Hole ◽  
Paramagnetic Resonance ◽  
Defect Centers ◽  
Defect Creation ◽  
Electron Paramagnetic

Effects of ionizing irradiation on defect creation processes have been studied in rare earth (RE)-doped (RE = Sm, Gd, Eu, Ce, Nd) aluminoborosilicate glass with use of the electron paramagnetic resonance (EPR) and optical spectroscopy. As a function of RE ion nature, we observe that doping significantly influences the nature of the defects produced during irradiation and more specifically the relative proportions between hole and electron defect centers. Strong decrease of defect production efficiency under ionizing radiation independence on both the RE doping content and on the relative stability of the RE different oxidation states is also clearly revealed. The results could be explained by dynamical reversible trapping of the electron-hole pairs produced during irradiation on the different RE charge states as well as by RE segregation and pre-existing defects speciation in ABS glass structure.

Defect induced p-type conductivity in zinc oxide at high temperature: electron paramagnetic resonance spectroscopy

Nanoscale ◽  
2017 ◽  
Vol 9 (31) ◽  
pp. 10983-10986 ◽  
Author(s):  
Emre Erdem
Keyword(s):  
Surface Defects ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Resonance Spectroscopy ◽  
Paramagnetic Resonance ◽  
Type Conductivity ◽  
Zno Nanocrystals ◽  
Defect Centers ◽  
Temperature Electron ◽  
P Type ◽  
Electron Paramagnetic

It has been observed that the defect centers on the surface play a crucial role in the conductivity behavior of ZnO. Above 300 °C only surface defects can be visible in EPR spectra for ZnO nanocrystals which indicate p-type conductivity.

scholarly journals DEPENDENCE OF ELECTRON PARAMAGNETIC RESONANCE (EPR) SPECTRUM PARAMETERS ON THE KIND OF MEAT AND FISH TREATED BY IONIZING RADIATION

2018 ◽  
Vol 97 (9) ◽  
pp. 873-876
Author(s):  
R. T. Timakova ◽  
Sergei L. Tikhonov ◽  
O. V. Evdokimova ◽  
I. V. Butenko
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Ionizing Radiation ◽  
Bone Tissue ◽  
Radiation Treatment ◽  
Raw Materials ◽  
Food Products ◽  
Epr Spectrum ◽  
Paramagnetic Resonance ◽  
Epr Signal ◽  
Electron Paramagnetic

Regulation of the use of ionizing radiation for treating food products and agricultural raw materials in Russia in 2017 suggests a wide dissemination of radiation technologies in the food industry, but manufacturers of food products processed by ionizing radiation do not indicate on the label the relevant information. Because of this, the identification of the domestic consumer market of food products processed by ionizing radiation will reduce the number of violations of requirements of state standard State standards (GOST) 33800-2016 “Production of food irradiated. General labeling requirements”. To determine whether irradiation of food raw materials and foodstuff, used the method of electron paramagnetic resonance (EPR), with each of the food products treated by ionizing radiation has its own characteristic EPR spectrum. In this regard, the aim of the research is to identify the dependence of the parameters of the EPR spectrum from meat, fish and poultry treated with ionizing radiation. Samples of bone tissue (SBT) meat, fish and poultry were subjected to radiation treatment with a linear electron accelerator model UELR-10-10С2 with energies up to 10 MeV. Studies of samples were carried out on the portable automated EPR spectrometer brand Labrador Expert X-band. Found that despite treatment samples of bone tissue with the same dose of ionizing radiation (12 kGy), the EPR signal depends on the type of vertebrates, the structure of the tissue sample, and other factors. Bone samples of beef and pork have a higher sensitivity to irradiation. Recorded a steady correlation between increasing the area of the EPR signal parameters: amplitude is of 0.99, the width of the peak signal, respectively 0,979 (the degree of strength of statistical relationships Chedoke very high). Processing of the obtained results of the EPR spectrum provides a high degree of confidence (p≤0.05) to identify how previously non-irradiated and radiation-processed various meats, fish and poultry.

Electron Paramagnetic Resonance and Optical Study of Radiation-Induced Defect Centers in Doped Silica Glasses

1985 ◽  
Vol 61 ◽  
Author(s):  
Robert N. Schwartz ◽  
Gregory L. Tangonan ◽  
G. Richard Blair ◽  
Walee Chamulitrat ◽  
Larry Kevan
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Radiation Dose ◽  
Optical Fibers ◽  
Optical Loss ◽  
Complex Spectrum ◽  
Epr Spectrum ◽  
Paramagnetic Resonance ◽  
Silica Glasses ◽  
Defect Centers ◽  
Electron Paramagnetic

ABSTRACTGamma- and UV-induced defect centers in germanium and fluorine doped silica have been studied by electron paramagnetic resonance (EPR) spectroscopy. The complex spectrum at g≃2 in γ-irradiated germanium doped glass corresponds to a superposition of resonances from several germanium E′-centers. In UV-irradiated samples, however, the EPR spectrum is dominated by only one type of germanium E′-centers. Significant spectral simplification of γ-irradiated germanium doped silica can be achieved by heating or broadband photoirradiation. Similar results are observed in multimode germanium doped core optical fibers. UV-induced optical loss spectra in the 0.5–1.5 μm wavelength range were also measured in these core fibers as well as the growth kinetics of the UL-induced absorption. Gamma-irradiation of fluorine doped silica generated two different types of silicon E′-centers, Ea1. At lower radiation dose one sees a mixture of Ea1 and Ea2, but at higher radiation dose Ea2 dominates. A spectrum dominated by the Ea2 variant is also observed in LW-irradiated samples and in photobleached low gamma dose samples.

scholarly journals Rapid scan electron paramagnetic resonance at 1.0 GHz of defect centers in γ-irradiated organic solids

2016 ◽  
Vol 85 ◽  
pp. 57-63 ◽  
Author(s):  
Yilin Shi ◽  
George A. Rinard ◽  
Richard W. Quine ◽  
Sandra S. Eaton ◽  
Gareth R. Eaton
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Paramagnetic Resonance ◽  
Organic Solids ◽  
Rapid Scan ◽  
Defect Centers ◽  
Electron Paramagnetic

Synthesis and characterization of nonconventional nickel-titania glasses by sol-gel route

1999 ◽  
Vol 14 (3) ◽  
pp. 1069-1073 ◽  
Author(s):  
T. K. Kundu ◽  
D. Chakravorty
Keyword(s):  
Composition Range ◽  
Glass Structure ◽  
Sol Gel ◽  
Microscopic Level ◽  
Synthesis And Characterization ◽  
Paramagnetic Resonance ◽  
Gel Technique ◽  
Electron Paramagnetic ◽  
Scanning Electron

Glasses in the NiO–TiO2 system in the composition range 15 to 25 mol% of NiO have been synthesized by the sol-gel technique by heat treatment of the precursor sol at 500°C. The glass structure is built up by crosslinking of two units, namely TiO6 octahedron and NiO3 triangle. Glassy structure is confirmed at a microscopic level by scanning electron microscopy. An increase in the values of peak-to-peak width of electron paramagnetic resonance with increasing concentration of Ni2+ is attributed to an enhanced interaction between neighboring paramagnetic Ni2+ ions.

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