Sintering of Textured YBa2Cu307-x Under Intensive 60Co Gamma Irradiation

1994 ◽  
Vol 354 ◽  
Author(s):  
Elvira M. Ibragimova ◽  
Eldar M. Gasanov ◽  
Makhmud Kalanov ◽  
Marquis A. Kirk ◽  
Ken C. Goretta
Keyword(s):  
Gamma Irradiation ◽  
Dose Rate ◽  
Subsurface Layer ◽  
Gamma Dose ◽  
Ordered Structure ◽  
Sintering Process ◽  
Superconducting Properties ◽  
Oxygen Sublattice ◽  
60Co Gamma ◽  
Sem Analyses

AbstractA study of structural and superconducting characteristics of YBa2Cu307-x ceramics sintered after and in the course of gamma-irradiation is reported. Using X-difraction and SEM analyses and transport measurements, it has been shown that mainly the subsurface layer of crystallites and intergrain contacts are affected by the irradiation by means of sorption/desorption of oxygen and ordering/disordering in oxygen sublattice, which depends on gamma dose rate and dose. The irradiation provides the sintering process with an additional superthermal energy to form the orthorhombic well-ordered structure and to obtain dense ceramics possessing strong intergrain contacts and improved and stable superconducting properties

scholarly journals Оптические характеристики облученных гамма-лучами полимерных сцинтилляторов

2020 ◽  
Vol 128 (9) ◽  
pp. 1249
Author(s):  
С.В. Афанасьев ◽  
А.Ю. Бояринцев ◽  
И.А. Голутвин ◽  
Э.М. Ибрагимова ◽  
А.И. Малахов ◽  
...  
Keyword(s):  
Gamma Irradiation ◽  
Dose Rate ◽  
Absorption Spectra ◽  
Optical Transmission ◽  
Transmission Losses ◽  
Optical Losses ◽  
Dose Rates ◽  
60Co Gamma ◽  
Plastic Scintillators ◽  
Transmission And Absorption

The effects of dose rate and dose of 60Co gamma-irradiation and oxidation on optical transmission and absorption spectra of plastic scintillators of BC-408 (USA), UPS-923A (Ukraine) and LHE (JINR) were studied at 300 K in air and hermetic pack at dose rates within 0.00022 до 0.0032 МGy/h and to doses 0.043 и 0.2 МGy. The irradiation increases the transmission losses in the range of 400-850 nm as the dose grows. It was not found a noticeable influence of adsorbed oxygen on the induced optical losses at the mentioned conditions.

scholarly journals Inter-calibration of gamma dose rate detectors on the European scale

2009 ◽  
Vol 44 (5) ◽  
pp. 777-784 ◽  
Author(s):  
U. Stöhlker ◽  
M. Bleher ◽  
T. Szegvary ◽  
F. Conen
Keyword(s):  
Dose Rate ◽  
Gamma Dose ◽  
Gamma Dose Rate

Microstructure and superconducting properties of Bi-2223/Ag tapes fabricated in the pressing–melting–sintering process

2010 ◽  
Vol 470 (20) ◽  
pp. 1388-1391 ◽  
Author(s):  
X.Y. Lu ◽  
D. Yi ◽  
H. Chen ◽  
A. Nagata ◽  
K. Sugawara
Keyword(s):  
Sintering Process ◽  
Superconducting Properties

scholarly journals Изменение характеристик переизлучающих волокон Y-11 и O-2 под действием гамма облучения

2020 ◽  
Vol 128 (12) ◽  
pp. 1973
Author(s):  
А.Ю. Афанасьев ◽  
А.Ю. Бояринцев ◽  
И.А. Голутвин ◽  
Э.М. Ибрагимова ◽  
А.И. Малахов ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Dose Rate ◽  
Room Temperature ◽  
Low Dose ◽  
Low Dose Rate ◽  
60Co Gamma ◽  
60Co Gamma Radiation

The effect of 60Co gamma radiation on the intensity of the reemitted light at the exit from WLS-fibers of Y-11 M and O-2 M type WLS fibers and the subsequent restoration of the characteristics of irradiated fibers after exposure to room temperature are investigated. Irradiation of a low dose rate (0.048 Mrad / h) to a dose of 1 Mrad leads to a slight decrease in the intensity of the reemitted light at the exit of both types of fibers, and with a further increase in the dose, the curve does not change. When irradiated with a dose rate of 0.158 Mrad / h, the characteristics of both types of fibers deteriorate significantly. When the irradiated samples are held at room temperature, fiber characteristics are restored.

Primary Shielding Design for an Optimized Molten Salt Reactor

2013 ◽  
Author(s):  
Zhihong Zhang ◽  
Xiaobin Xia ◽  
Jianhua Wang ◽  
Changyuan Li
Keyword(s):  
Molten Salt ◽  
Dose Rate ◽  
Gamma Dose ◽  
Acceptable Level ◽  
Gamma Dose Rate ◽  
Molten Salt Reactor ◽  
Thermal Shield ◽  
Oak Ridge ◽  
The Core ◽  
Shielding Design

Molten salt reactor (MSR) system, a candidate of the Generation IV reactors, has inherent safety, on-line refueling and good neutron economy as typical advantages. An optimized MSR is developed by changing the size of fuel channel and the graphite-to-molten salt volume radio, based on the Molten-Salt Reactor Experiment (MSRE), which was originally developed at the Oak Ridge National Laboratory (ORNL). In this paper, shielding calculations for the optimized MSR are presented. The goal of this study is to determine the necessary shielding to decrease the neutron and gamma dose rate to the acceptable level according to national regulations. The operating temperature of the optimized MSR is designed in the range of 500 °C–700 °C, heat removal is also considered in the shielding design. The shielding calculations are carried out by using Monte Carlo method. The shielding system of the optimized MSR consists of 7 zones: the core, the core can, the reactor vessel, the thermal shield, the reactor cell containment, the shield tank and the concrete wall. The combinations of shielding materials in the thermal shield were evaluated. The thermal shield filled with carbon steel balls and circulating water gets an excellent shielding performance and heat removing effects. The neutron spectra and dose distributions, as well as the energy deposition over different shields have been analyzed. The total neutron dose rate outside the thermal shield is attenuated by a factor of about 104, and the gamma dose rate by a factor of about 103. These results show that the shielding design could low dose rate to an acceptable level outside the shielding and far below dose limit required.

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