• Journal of Korean Vacuum Science & Technology
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• 제4권4호
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• pp.112-121
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• 2000

The paper investigates electrical discharge properties in neon gas mixed with xenon. The breakdown temperature T$\sub$b/ and voltage V$\sub$b/ are obtained in terms of the gas mixture ratio X. It is shown that the breakdown voltage decreases, reaches the minimum value at X=0.02 and then increases again, as the mixture ratio X increases from zero to unity. Therefore, mixing the neon gas with a few percent of xenon is the most beneficial to reduce the breakdown voltage. Plasma density at breakdown in neon gas mixed with xenon is described in terms of the gas mixture ratio. The optimum value of mixture ratio for highest plasma density is found to be Xm=0.03. A preliminary experiment of AC-PDP is carried out for neon gas mixed with a few percent of xenon to verify some of the theoretical models. The experimental data agree qualitatively well with theoretical predictions.

• Nuclear Engineering and Technology
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• 제52권12호
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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.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.285-288
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• 2002

In this study, we investigate electron transport properties in xenon gas by using a Monte Carlo technique for electrons with energies below 10 keV. First of all, we determine a set of electron collision cross sections with xenon by scrutinizing the cross section data taken from many publications. Then, the W value and the Fano factor for electrons in gaseous xenon are computed by the Monte Carlo simulation on the assumption that electrons undergo single collision events including elastic, excitation and ionization processes. We also evaluate the production number of excited atoms.

• 한국군사과학기술학회지
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• 제13권3호
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• pp.493-502
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• 2010

In this paper, the ionization characteristics of noble gases are studied numerically behind strong shock waves. As a first step, the equilibrium ionization mechanism of noble gases is modeled in wide ranges of temperature and pressure. As a next step the equilibrium ionization model is coupled with fluid dynamic equations to analyze the local thermodynamic equilibrium(LTE) ionization process at high temperature and pressure conditions behind the strong imploding shock waves. The ionization characteristics of xenon gas is studied in a wide range of test conditions with thermal radiation effects. Hence, the results give optimal conditions of maximum ionization and radiation behind the imploding shock waves.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.918-925
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• 1996

The effect of structured water by dissolution of xenon was examined from the view point of the suppression of both browning and respiratory metabolism of broccoli. The structured water is formed duet to hydrophobic interaction when xenon gas dissolves into water. NMR measurements were carried out to determine proton spin-spin relaxation time, T2, for water. There was a difference in proton T2 between distilled water and structured water. This can be interpreted as the change of water structure. Fro the broccoli cut in half stored for 16 days at 279K, the section color did not change appreciably for the sample whose water was structured by dissolution of xenon whose initial partial pressure was 0.39MPa. In contrast to this, the browning of section surface was observed for the sample stored under the condition of nitrogen gas at the same partial pressure as xenon and for the sample stored under atmospheric condition . These results led to the conclusion that the suppression of b owning by oxidation was due to structured water but not to applied pressure. Adding to this, the water structured by xenon has resulted in suppression of respiratory metabolism of broccoli.

• 대한화학회지
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• 제36권3호
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• pp.351-359
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• 1992

알칼리 토금속 양이온을 함유하고 있는 Y 제올라이트와 Xe 간의 상호 작용을 이해하기 위하여 Xe의 흡착과 $^{129}Xe$ 핵자기 공명(NMR) 분광법을 이용하였다. 고순도의 NaY 제올라이트 시료를 합성하여 여기에 $Ca^{2+}$와 $Ba^{2+}$를 각각 이온 교환시켜서 CaY와 BaY 제올라이트 시료들을 얻었다. 부피 흡착 실험방법에 따라서 260∼320 K 사이에서 이 시료들의 Xe 흡착 등온선을 측정하였으며 296 K에서 $^{129}Xe$ NMR의 화학적 이동을 측정하였다. 이 시료들에 흡착된 Xe 기체가 제올라이트 표면과 알칼리 토금속 이온들로 구성된 흡착자리들 사이를 매우 빠르게 움직인다고 가정하였을 때 Xe의 화학적 이동을 정량적으로 설명할 수 있었다. 이 결과 알칼리 토금속 이온들이 $Na^+$ 이온이나 제올라이트 골격 표면보다도 Xe을 훨씬 더 강하게 흡착한다는 것을 의미한다. 이 연구에서는 이와 같은 흡착 세기의 차이를 이용하여 Xe 흡착 등온선을 분석하면 Y 제올라이트 수퍼케이지 속에 존재하는 알칼리 토금속 이온의 갯수를 구할 수 있다는 사실을 밝혀내었다.

• 한국환경과학회지
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• 제11권7호
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• pp.749-755
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• 2002

The effects of noble gas (such as helium, neon, argon, krypton, and xenon) on the sonolytic decomposition of water and 2-methyl-2-propanol(t-butanol) with 200 KHz high power ultrasound were investigated. The physical properties of the noble gas have an effect on the formation rate of products $(H_2O_2,\;H_2,\;O_2)$ and the decomposition rate on the sonolytic decomposition of water. The pyrolysis products, such as methane, ethane, ethylene, and acetylene are formed during the sonolytic decomposition of t-butanol. From the estimation of the ratio $[C_2H_4+C_2H_2] / [C_2H_6]$, the cavitation temperature would be varied by the used noble gas. In all cases for the sonolytic decomposition of water, t-butanol, and diethyl phthalate, the decomposition rates were xenon > krypton > argon > neon > helium with a significant difference and were closely correlated with the formation rate of OH radical and high temperature inside the cavitation bubble under each noble gas.

• 한국항공우주학회지
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• 제37권4호
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• pp.419-424
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• 2009

소형 인공위성의 궤도 보정을 위한 300 W급 홀 추력기의 제논연료공급장치를 개발하였다. 가스 상태의 제논 연료를 150 bar에서 2 kg을 저장할 수 있으며, 0.5 SCCM의 미세 유량을 제어할 수 있다. 미세 유량을 제어할 수 있는 유량 제어밸브의 구동을 위해 시스템을 구성하고, 시험을 통해 성능검증을 수행하였다. 이를 통해 $1.0{\times}10^{-6}$ torr압력의 진공에서 연료공급장치가 성공적으로 동작함을 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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• pp.73-76
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• 2003

This paper describes the information for quantitative simulation of weakly ionized plasma. In previous paper, we calculated the electron transport coefficients in pure Xenon gas by using two-term approximation of Boltzmann equation. Therefore, in this paper, we calculated the electron transport coefficients(W, $N{\cdot}D_L$ and $D_{L/{\mu}}$) in pure Xenon gas for range of E/N values from 0.01 ~ 500[Td] at the temperature was 300[K] and pressure was 1[Torr] by using multi-term approximation of the Boltzmann equation by Robson and Ness, The results of two-term and multi-term approximation of the Boltzmann equation has been compared with the experimental data by L. S. Frost and A. V. Phelps for a range of E/N.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1997년도 제13회 학술발표회 논문개요집
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• pp.198-200
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• 1997