• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2760-2770
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• 2020

A model for calculation of fuel temperature profile using binary gas mixture of Helium and Xenon for gap gas conductance is proposed here. In this model, the temperature profile of a fuel pencil from fuel centreline to fuel surface has been calculated by taking into account the dilution of Helium gas filled during fuel manufacturing due to accumulation of fission gas Xenon. In this model an explicit calculation of gap gas conductance of binary gas mixture of Helium and Xenon has been carried out. A computer code Fuel Characteristics Calculator (FCCAL) is developed for the model. The phenomena modelled by FCCAL takes into account heat conduction through the fuel pellet, heat transfer from pellet surface to the cladding through the gap gas and heat transfer from cladding to coolant. The binary noble gas mixture model used in FCCAL is an improvement over the parametric model of Lassmann and Pazdera. The results obtained from the code FCCAL is used for fuel temperature calculation in 3-D neutron diffusion solver for the coolant outlet temperature of the core at steady operation at full power. It is found that there is an improvement in calculation time without compromising accuracy with FCCAL.

• Current Optics and Photonics
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• v.4 no.6
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• pp.466-471
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• 2020

We analyze the transverse nuclear magnetizations of 129Xe and 131Xe in a vapor cell containing natural Xe, 87Rb, and buffer gases. Th e Xe atoms are polarized th rough spin-exch ange optical pumping (SEOP) with Rb atoms under low-magnetic-field conditions. From the free-induction-decay (FID) signal, we measure the nuclear magnetization of the Xe atoms in the Xe-Rb vapor cell. Furthermore, we measure the dependence of the gyromagnetic ratio on the magnetization of 129Xe and 131Xe by examining the amplitude of the FID signal of each isotope, and we evaluate the relationship between the magnetic field gradient and transverse relaxation rate for both of the 129Xe and 131Xe isotopes.

• Journal of Conservation Science
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• v.31 no.4
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• pp.443-455
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• 2015

To verifying the stability of Natural pigments for Dancheong which is available on the market was carried out as light resistance and gas corrosion test. In this particular case, we will confirm the characteristics of the only pigments except of Dancheong technique and influence of substance. Medium using for coloring are animal glue and synthetic resin that widely used for Dancheong in currently. Selected to artificial light source is a xenon arc lamp, contaminated gas is nitrogen dioxide gas in experiment. Degree of degradation of pigment were compared by measuring the degree of color change. The result of light resistance test, mineral pigments were good; color is green and blue type, soil pigments also good; color is yellow ocher, white clay, red clay etc. Gamboge, unghwang, cinnabar, red lead were confirmed not good. The result of gas corrosion test, most of the natural pigments were good condition except the red lead. Generally, animal glue samples had better than a synthetic resin samples.