제주도 용암의 Mossbauer 스펙트럼 연구

홍성락(Sung Rak Hong),고정대(Jeong Dae Ko),최원준(Won Jun Choi) 한국자기학회 2003 韓國磁氣學會誌 Vol.13 No.6

In this study, we analyzed the volcanic rock and scoria samples taken from special sites of Jeju island in two ways at the room temperature. One is the analysis of the chemical composition using X-ray fluorescence spectrometer, the other is the analysis of minerals in the samples, oxidized iron's genus, valence state and magnetic properties using X-ray diffractometry and Mossbauer spectroscopy. We believe that the volcanic rock and scoria samples are chiefly made of silicate minerals, like SiO₂, and they also have olivine, pyroxene, ilmenite, hematite and magnetite. The major Fe fractions of the volcanic rock samples are 2+ charge state and those of the scoria samples are 3+ charge state.

제주도 용암의 물리적 특성

홍성락 濟州大學校 基礎科學硏究所 2001 基礎科學硏究 Vol.14 No.2

제주도의 특정 4개지역을 선정하여 지역별로 화산암과 송이시료를 채취하여, 상온에서 이 시료에 대한 Mo¨ssbauer spectroscopy와 XRD를 이용한 실험결과를 보고한다. 시료에 대한 XRD실험에서 화산암에는 quartz, olivine, pyroxene, ilmenite, 송이에는 이 광물외에 hematite, magnetite등의 광물이 존재하고 있음을 확인하였다. 시료의 Mo¨ssbauer 스펙트럼으로부터 화산암은 olivine, pyroxene, ilmenite에 의한 세쌍의 quadrupole splitting을, 송이는 이 광물 외에 hematite, magnetite에 의한 두 쌍의 sextets을 얻었으며 화산암에 함유된 Fe는 약간의 Fe^(+3)를 제외하고는 거의 Fe^(+2)이고, 송이에 함유된 Fe는 약간의 Fe^(+2)를 제외하고는 거의 모두 Fe^(+3) 상태임을 확인하였다. We report the result of measurements using the Mossbauer spectroscopy and x-ray diffractometry(XRD) of samples of volcanic rock and scoria at room temperature which are distributed throughout four different sites on Jeju island. In the XRD results for these samples, we find that volcanic rock has minerals of quarts, olivine, pyroxene and ilmenite. Scoria has not only the aforementioned minerals but also hematite and magnetite. The Mossbauer spectra for Volcanic rock consists of three well defined quadrupole doublets of olivine, pyroxene and ilmenite with a dominant 2^(+) charge state and a small percentage of 3^(+) charge state of iron. On the other hand in Mossbauer spectra for scoria, we find that scoria has not only two well defined quadruple doublets of olivine and pyroxene but also two sextets of hematite and magnetite with a dominant 3^(+) charge state and a small percentage of 2^(+) charge state of iron.

Mossbauer 분광학과 이성질체이동, 공명흡수 면적을 이용한 Debye 온도결정

洪性樂 濟州大學校 基礎科學硏究所 1988 基礎科學硏究 Vol.1 No.1

In this study, we have improved the methods determining the Debye temperature. From a fact that the kinetic temperature proposed by Mazo and Kirwood simplize the Mossbauer data we could compute the ?? using isomer shift variance about low temperature range, 50∼300K, and linearizing temperature To of data. Futhermore, we have tried automatic iteration process of log resonance absorption area ratios about ?? to determine the Debye temperature accurately. From each methods, we knew the ?? of iron foil stands on 476∼485 K. The credible ?? from Mossbauer data can be determined by the careful measurement and fine computer technique.

ZnSe-ZnS : Mn 직류 박막형 전자발광 소자의 제작 및 특성조사

洪性樂,崔致圭,金斗哲,玄東杰 제주대학교 1988 논문집 Vol.27 No.-

A ZnSe-ZnS : Mn dc thin flim electroluminescene device was fabricated electron beam evaporation method and investigated the charcteristics. The brightness-voltage characteristics for dc operation were measured . The threshold voltage was 32V and at 60V the maximum brightness was 95fL. The brightness depending on the layer thickness of thin flim increased and a brightness tended to saturate above 8000A and the optimum temperature of substrate was 200-230℃. The spectrum of this device had a maximum intenty at wavelength 585nm.

두개의 不變理論에 대한 量子力學的 考察

洪性樂,朴奎殷,金健鎬 제주대학교 1977 논문집 Vol.9 No.-

There are some invariance principles in quantum mechanics. They are space translation inva- riance, Space rotation invariance, time reversal invariance, Galilean invariance and charge conjugation. Among them, the space translation invariance and space rotation invariance are especially important. in this paper we sought the unitary operators governing the two above mentioned invariance transfomations,and the two principles led to the conservation law of linear momentum and angular rmomentum.

Ni1-xCdxFeAlO₄계의 Mossbauer 스펙트럼 연구

홍성락,고정대,백승도 濟州大學校 基礎科學硏究所 1998 基礎科學硏究 Vol.11 No.2

Ni1-xCdxFeAlO₄계의 Mossbauer스펙트럼은 x가 0.2이하인 경우에는 초상자성 이완현상을, x가 0.3~0.5인 경우에는 준강자성에 의한 sextet를 x가 0.7, 0.8인 경우에는 강자성 이완현상, x가 0.8이상인 경우에는 상자성에 의한 doublet가 나타난다. x가 0.2이하인 시료에서 치환된 Cd²이온은 주로 A-site의 Al³이온을 B-site로 이동시키고, 계속적인 Cd²이온의 증가에 따라 A-site의 Fe³+ 이온도 B-site로 이동하게 된다. Ni1-xCdxFeAlO₄계의 초상자성 이완 현상은 A-site의 Al³이온에 의한 것으로 강자성 이완현상은 치환된 Cd²+이온에 의한 것으로 설명할 수 있고, Yafet-Kittel자기구조에 따라 Ni1-xCdxFeAlO₄계의 자기적 성질을 해석할 수 있다. The Mossbauer spectra of the Ni1-xCdxFeAlO₄system were investigated with the Cd content X at room temperature. The spectra of the samples exhibit various patterns as follows 1) superparmagnetic relaxation for 0≤x≤0.2, 2)ferrimagnetic sextet for 0.3≤x≤0.5, 3) ferromagnetic relaxation for x=0.6, 0.7, 4)paramagnetic doublet for 0.8≤x≤1, with the Cd content x. In the samples with X values from O to 0.2, the substituted Cd²+ ions transfer the Al³+ ions from A-site to B-site mainly. The superparamagnetic relaxation effect and the ferromagnetic relaxation effect are derived from the Al³,Cd²respectively. The magnetic structrue of the Ni1-xCdxFeAlO₄system was explained by the Yafet-Kittel model.

Mossbauer 분광법을 이용한 Ni-Cd Ferrite의 미시적 연구

홍성락,최달하,백승도,이경행,문용식,홍치유 濟州大學校 基礎科學硏究所 1989 基礎科學硏究 Vol.2 No.1

Ceramic sintering 법으로 제작한 ??의 X-ray 회절선과 80 ∼ 900K의 온도영역에서 측정한 Mossbauer spectrum을 분석하였다. Ni-Cd ferrite의 격자상수는 Cd 농도가 증가함에 따라 선형적으로 증가하며, Mossbauer spectrum과 parameter의 온도의존성을 조사한 결과 자기전이온도(??)는 Cd 농도가 증가함에 따라 감소하고, Debye 온도(??)는 Cd 농도에 따른 의존성이 없다. In this study, the Mossbauer spectra of ??, prepared by a ceramic sintering method, were investigated in the temperature range of 80K∼900K. The X-ray diffraction patterns of the all samples show the single phase spinel structure and the lattice constant increases linearly as increasing Cd concentration. The center shift values of the all samples decrease as increasing temperature regardless of Fe site, but the quadrupole splitting values are indepenent of the temperature. The magnetic hyperfine field and resonant absorption area decrease as increasing temperature. From the temperature dependence of the Mossbauer parameters, it is concluded that the magnetic transition temperature decrease as increasing Cd concentration and the Debye temperature is independent of Cd concentration.

Electron-Phonon 相互作用에 對한 小考

洪性樂 慶北工業專門大學 1974 論文集 Vol.11 No.-

Electron-phonon interaction is investigated by means of quantum field theoretical methods.

제주도의 신석기 시대 토기에 관한 Mossbauer 연구

홍성락,고정대,강동우 濟州大學校 基礎科學硏究所 1995 基礎科學硏究 Vol.8 No.1

The constitutional component, firing temperature and firing atmosphere of plain coarse pottery sherds unearthed from the remains of the Bawignul site of Bukchon in Cheju lsland at a neolithic era were studied by X-ray diffraction(XRD), thermomechanical analysis and Mossbauer spectroscopy. By the analysis of X-ray diffraction, the clay minerals of the plain coarse pottery sherds of the neolithic era contained no peaks by resoulution, but did contain those of quartz and plagioclase. By thermomechanical analysis, the transition of quartz of plain coarse pottery sherds appeared at about 600℃ and heat constraction of plain coarse pottery sherds clearly at about 820℃. The refiring of plain coarse pottery sherds of the neolithic era results in the four characteristic temperature ranges from the change of quadrupole splitting by Mossbauer spectrum at room temperature. It is estimated from 800℃ to 900℃ that original firing temperatures of plain coarse pottery sherds of the neolithic era at Bukchon through the change of Mossbauer parameters, X-ray diffraction analysis and thermomechanical analysis.

Silicate 유리의 Mossbauer 분광학적 연구

홍성락,문찬호,홍치유,백승도,최달하 동국대학교 자연과학연구소 1986 자연과학연구 논문집 Vol.6 No.-

10Nio-10Fe₂O₃-30Na₂O-50SiO₂유리에 대한 Mossbauer 분광학적인 연구를 저온실험과 유리의 열처리효과에 대해 수행하엿다. center shift 와 quadrupole splitting 및 공명흡수 면적은 저온으로 갈수록 증가하였으며, 유리의 Dabye 및 Einsteine 온도는 각각 450K 와 352K 이었다. 열처리온도가 증가함에 따라 I.S. 와 Q.S. 는 감소하였으며, 특히 710℃이상에서 열처리한 시료는 NiFe₂O₄에 의한 magnetic hyperfine splitting이 관찰되었다. Using the 10Nio-10Fe₂O₃-30Na₂O-50SiO₂glass, we investigated the Mossbauer parameters of quenched glass and heat-treated glasses. The Debye and Einstein temperature of the quenched glass were determined by the center shifr and the kinetic tmeperature. According to the X-ray diffraction patterns, NiFe₂O₄was precipitated in the glass by heat treatment. Both the isomer shift and quadrupale splitting were decreased as the heat treatment temperature increased. The glasses, heat-treated above 710℃, showed magnetic hyperfine splitting for NiFe₂O₄.