The effect of gamma irradiation on the activation energy of bulk and track etching in Lexan track detector

In this paper, high purity boron carbide samples were irradiated by [Formula: see text]Co gamma radioisotope source (0.27 Gy/s dose rate) with 50, 100, 150 and 200 irradiation hours at room-temperature. The unirradiated and irradiated boron carbide samples were heated from 30[Formula: see text]C to 1000[Formula: see text]C at a heating rate of 5[Formula: see text]C/min under the argon gas atmosphere of flow rate 20 ml/min. Thermogravimetric (TG) and Differential Scanning Calorimetry (DSC) were carried out in order to understand the thermodynamic kinetics of boron carbide samples. The weight kinetics, activation energy and specific heat capacity of the unirradiated and irradiated boron carbide samples were examined in two parts, T [Formula: see text] 650[Formula: see text]C and T [Formula: see text] 650[Formula: see text]C, according to the temperature. The dynamic of quantitative changes in both ranges is different depending on the irradiation time. While the phase transition of unirradiated boron carbide samples occurs at 902[Formula: see text]C, this value shifts upto 940[Formula: see text]C in irradiated samples depending on the irradiation time. The activation energy of the unirradiated boron carbide samples decreased from 214 to 46 J/mol in the result of 200[Formula: see text]h gamma irradiation. The reduction of the activation energy after the irradiation compared to the initial state shows that the dielectric properties of the irradiated boron carbide samples have been improved. After the gamma irradiation, two energy barrier states depending on the absorption dose of samples were formed in the irradiated samples. The first and second energy barriers occurred in 0.56–0.80 and 0.23–0.36 eV energy intervals, respectively. The existence of two energy levels in the irradiated boron carbide indicates that the point defects are at deep levels, close to the valence band.

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The etching, optical and thermal response of a newly developed nuclear track detector called NADAC-ADC copolymer to gamma-irradiation

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/s10967-010-0673-7 ◽

2010 ◽

Vol 287 (1) ◽

pp. 273-276 ◽

Cited By ~ 5

Author(s):

Vivek Chavan ◽

P. C. Kalsi ◽

Amol Mhatre

Keyword(s):

Gamma Irradiation ◽

Thermal Response ◽

Track Detector ◽

Nuclear Track Detector

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On the use of polyethyleneterephthalate as solid state nuclear track detector: Kinetics and mechanism of particle track etching

Nuclear Instruments and Methods in Physics Research ◽

10.1016/0167-5087(83)90449-0 ◽

1983 ◽

Vol 213 (2-3) ◽

pp. 507-511 ◽

Cited By ~ 22

Author(s):

H.B. Lück

Keyword(s):

Solid State ◽

Track Detector ◽

Kinetics And Mechanism ◽

Particle Track ◽

Nuclear Track Detector ◽

Track Etching

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Research of the Effects on a Nuclear Cable Material Irradiated by Beta/Gamma Irradiation

Volume 2: Plant Systems, Construction, Structures and Components; Next Generation Reactors and Advanced Reactors ◽

10.1115/icone21-16198 ◽

2013 ◽

Author(s):

Weixia Zhong ◽

Jiansheng Sun ◽

Jinping Liu ◽

Ping Sun

Keyword(s):

Activation Energy ◽

Glass Transition ◽

Gamma Radiation ◽

Gamma Irradiation ◽

Irradiation Dose ◽

Loss Modulus ◽

Absorbed Dose ◽

Transition Process ◽

Gamma Irradiated ◽

Movement Unit

In this paper, irradiated samples by different irradiation doses of the beta/gamma radiation from a selected nuclear cable material, which were studied by tensile machine, DSC and DMTA. The research results show that the elongation at break (EAB) drops with absorbed dose of beta/gamma radiation and at the same dose the EAB drop for beta-irradiated samples is higher than that for gamma-irradiated samples, which means that this material becomes more brittler with more irradiation. The OITP value for the irradiated samples exhibits pronounced drop with absorbed beta/gamma irradiation dose. And moreover, the OITP value of these gamma irradiated samples drops faster than that of those beta irradiated samples. DMTA researches show that the storage modulus (E′) and the loss factor (tanδ = E″/E′, E″ represents the loss modulus) of the irradiated samples present higher values with the increase dose of beta /gamma radiation. It is interest that the E′ behaves firstly an increase, then decreases by rising the temperature within the temperature range of −30–20 °C, and this trend becomes pronounced with increase of irradiation dose, combined with the activation energy, correspond to the glass transition process, for all the irradiated samples which hints that the glass transition process may be hindered in terms of a higher activation energy, but the movement unit could be smaller with a lower Tg, as a result of the beta/gamma irradiation.

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