• 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.

• Nuclear Engineering and Technology
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• 제56권2호
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• pp.601-610
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• 2024

This paper gives an extensive analysis on the characterization of xenon isotopic ratios for various nuclear reactors and nuclear explosions through neutronic depletion codes. The results of the characterization can be used for discriminating the sources of the xenon isotopes' release among the nuclear explosions and nuclear reactors. The considered sources of the xenon radionuclides do not only include PWR, CANDU, and nuclear explosions using uranium and plutonium bombs, but also IRT-200 and 5MWe Yongbyon (MAGNOX reactor) research reactors operated in North Korea. A new data base (DB) on xenon isotopic activity ratios was produced using the results of the characterization, which can be used in discrimination of the sources of xenon isotopes. The results of the study show that 5MWe Yongbyon reactor has quite different characteristics in ¹³⁵Xe/¹³³Xe ratio from the PWRs and the nuclear reactors have different characteristics in ¹³⁵Xe/¹³³Xe ratios from the nuclear explosions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.41-45
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• 2005

In this paper, parameters of electron temperature and density for the mercury-free lighting-source were measured to diagnosis and analyze in Xe based inductively coupled plasma(ICP). In results at several dependences of 20~100 mTorr Xenon pressure, 50~200W RF power and horizontal distribution were especially mentioned. When Xe pressure was 20mTorr and RF power was 200W, the electron temperature and density were respectively 3.58eV and $3.56{\times}10^{12}cm^{-3}$. The key parameters of Xe based ICP depended on Xe pressure more than RF power that could be verified. A high electron temperature and low electron density with a suitable Xe pressure are indispensible parameters for Xe based ICP lighting-source.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2418-2420
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• 2005

In this paper, parameters of electron temperature and density for the mercury-free lighting-source were measured to diagnosis and analyze in Xe based inductively coupled plasma(ICP). In results at several dependences of $20{\sim}100mTorr$ Xenon pressure, $50{\sim}200W$ RF power and horizontal distribution were especially mentioned. When Xe pressure was 20mTorr and RF power was 200W, the electron temperature and density were respectively 3.58eV and $3.56{\times}10^{12}cm^{-3}$. The key parameters of Xe based ICP depended on Xe pressure more than RF power that could be verified. A high electron temperature and low electron density with a suitable Xe pressure are indispensible parameters for Xe based ICP lighting-source.

• Journal of Radiation Protection and Research
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• 제40권3호
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• pp.181-186
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• 2015

방사성 제논 탐지는 공기 중 $^{131m}Xe$, $^{133}Xe$, $^{133m}Xe$ 및 $^{135}Xe$를 저준위 백그라운드 계측 시스템으로 검출하여 지하 핵실험 여부를 규명하는 핵심기술 중 하나이다. 방사성 제논 감시는 공기 포집, 제논 추출, 측정 및 분석을 통해 수행되며, $^{135}Xe$의 최소검출가능농도는 비교적 짧은 반감기로 인해 포집, 추출 및 측정시간에 따라 큰 차이를 보이게 된다. 본 연구에서는 방사성 제논 계측 시스템의 정해진 시료 포집 및 전처리 조건에서 최적의 방사성 제논 측정시간을 도출하기 위해 이론적 접근 및 SAUNA 시스템을 이용한 실험을 통해 최소의 MDC를 보이는 측정시간을 결정하고 이론적 계산과 실험결과에 대하여 비교 평가하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1218-1220
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• 2005

We have developed laser absorption spectroscopy system for the measurement of excited Xe atoms in micro-discharged AC-PDP plasma. In this study, we have measured the absorption signals for the $1S_5$ xenon metastable state in the PDP cell with the various gas mixtures of Ne-Xe(1%), Ne-Xe(4%) and Ne-Xe(10%) under fixed gas pressure of 350 Torr and the eletrode gap distance of 50um. It is found that the maximum excited xenon densities are $1.2^{\ast}10^{12}\;cm^{-3}$, $1.8^{\ast}10^{12}\;cm^{-3}$ and $2.7^{\ast}10^{12}cm^{-3}$ for gas mixtures of Ne-Xe(1%), Ne-Xe(4%) and Ne-Xe(10%) respectively, in this experiment.

• Nuclear Engineering and Technology
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• 제52권6호
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• pp.1131-1136
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• 2020

Xenon behaves differently in molten salt reactors (MSRs) compared to solid fuel reactors. This behavior needs exploring due to the large reactivity effect of the ¹³⁵Xe isotope, given the current interest in MSR power plant development for commercial deployment. This paper focuses on select topics in xenon transport, reviews relevant past works, and proposes specific research questions to advance the state of the art in each of the focus areas. Specifically, the paper discusses the issue of xenon solubility in MSRs, the behavior of particulates circulating in MSR fuel salt and its influence on the xenon transport, the possibility of ionization of xenon atoms which changes its effective size and thus affects its mass transport, and finally the issue of circulating void fraction and how it is measured. This work presents specific recommendations for MSR designers to research the limits of Henry's law validity, circulating particulate scrubbers, validity of mass transport coefficients in high radiation fields, and the effects of pump speed on circulating void fraction.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.415-415
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• 2010

면방전 구조의 AC-PDP는 페닝 혼합 기체 중에서 Xe 플라스마에서 발생되는 VUV (Vacuum Ultra Violet) 에 의해 들뜬 형광체로부터 가시광이 발생된다. Xe 여기종은 828 nm의 공명준위를 거쳐 147 nm의 진공자외선을 방출하며 823 nm의 준안정준위에서 분자선을 거쳐 173 nm의 진공 자외선을 낸다. 이러한 Xe 여기종의 밀도를 측정하기 위해서는 828 nm와 823 nm의 레이저를 외부에서 인위적으로 조사하여 측정하면 IR (Infrared)의 흡수전과 흡수후의 빛의 세기로 Xe 여기종의 밀도 및 분포를 계산할 수 있다. 본 실험에서는 823 nm에 초점을 두었으며 LAS (Laser Absorption Spectroscopy) 기법을 통하여 He-Ne-Xe(15%, 20 %, 30%) 400Torr의 3종 기체의 Xe 함량에 따른 시공간의 Xe($1s_5$) 여기종 밀도 분포와 방전효율을 관측하였다. 최근 3전극 면방전형 AC-PDP 효율 향상을 위해 3종 기체의 Xe함량비의 방전기체에 대한 연구가 수행되고 있다. 이러한 기초 데이터는 혼합기체 조건에 따른 면방전 구조의 3전극 AC-PDP의 발광 효율을 개선하는 데 유용한 자료로 활용될 것이다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1577-1579
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• 2007

Xe content is one of important factors related to characteristics of the mercury-free flat fluorescent lamp. The electro-optical properties of lamp were investigated for wide range of Xe content in Xe-Ne mixing gas. The maximum luminance of $9,289\;cd/m^2$ and efficacy of 3 lm/W was obtained with Xe 90 %.

• Bulletin of the Korean Chemical Society
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• 제21권1호
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• pp.75-80
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• 2000

The positions of Xe atoms encapsulated in the molecular-dimensioned cavities of fully dehydrated Na-A have been determined. Na-A was exposed to 1050atm of xenon gas at 400 $^{\circ}C$ for seven days, followed by cooling at pressure to encapsulate Xe atoms. The resulting crystal structure of Na-A(7Xe) (a = 12.249(1) $\AA$, $R_1$ = 0.065, and $R_2$ = 0.066) were determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) $^{\circ}C$ and 1 atm. In the crystal structure of Na-A(7Xe), seven Xe atoms per unit cell are distributed over four crystallographically distinct positions: one Xe atom at Xe(1) lies at the center of the sodalite unit, two Xe atoms at Xe(4) are found opposite four-rings in the large cavity, and four Xe atoms, two at Xe(2) and others at Xe(3), respectively, occupy positions opposite and between eight- and six-rings in the large cavity. Relatively strong interactions of Xe atoms at Xe(2) and Xe(3) with $Na^+$ ions of four-, eight-, and six-rings are observed:Na(1)-Xe(2) = 3.09(6), Na(2)-Xe(3) = 3.11(2), and Na(3)-Xe(2) = 3.37(8) $\AA$. In each sodalite unit, one Xe atom is located at its center. In each large cavity, six Xe atoms are found, forming a distorted octahedral arrangement with four Xe atoms, at equatorial positions (each two at Xe(2) and Xe(3)) and the other two at axial positions (at Xe(4)). With various reasonable distances and angles, the existence of $(Xe)_6$ cluster is proposed (Xe(2)-Xe(3) = 4.78(6) and 4.94(7), Xe(2)-Xe(4) = 4.71(6) and 5.06(6), Xe(3)-Xe(4) = 4.11(3) and 5.32(4) $\AA$, Xe(2)-Xe(3)-Xe(2) = 93(1), Xe(3)-Xe(2)-Xe(3) = 87(1), Xe(2)-Xe(4)-Xe(2) = 91(4), Xe(2)-Xe(4)-Xe(3) = 55(2), 59(1), 61(1), and 68(1), and Xe(3)-Xe(4)-Xe(3) = 89($^{\circ}1$)). These arrangements of the encapsulated Xe atoms in the large cavity are stabilized by alternating dipoles induced on Xe(2), Xe(3), and Xe(4) by eight- and six-ring $Na^+$ ions as well as four-ring oxygens, respectively.