Sodium Nitroprusside 단결정의 Mossbauer Effect 연구

신영남,박성배,김재경 대구대학교 기초과학연구소 1999 基礎科學硏究 Vol.15 No.3

Sodium nitroprusside (Na2[Fe(CN)5NO]·2H2O) 단결성의 두께 변화에 대한 선폭의 증가를 측정하여 실험 선폭을 측정하였다. 또한 상온에서 sodium nitroprusside 단결정의 두께 증가에 대한 선폭의 증가를 조사하여 실험선폭을 측정하고, Dehye-Waller facters를 구하여 다른 실험결과와 비교하였다. 액체질소 온도에서 soium nitroprusside 단결정의 대칭성은 변하지 않고 Debye-Waller facters mean square displacement 값의 변화를 확인하고 또한 두께와 선폭치의 실험으로 측정한 Debye-Waller facter 값은 다른 실험값과 잘 일치하였으며 실험 선폭치는 자연 선폭에 대하여 약 16%에 상당하는 broadening을 확인 할 수 있었다.

Mo¨ssbauer Spectrometer의 속도변환 장치의 제작

申榮男,朴成培,金在慶,裵錫喆 大邱大學校附設 基礎科學硏究所 1991 基礎科學硏究 Vol.8 No.-

A constant acceleration Mossbauer spectrometer is constructed and a reference signal of the desired waveform to drive the feedback system is produced by the multichannel scaling board and with the help of operational amplifier. The stability and the linearity of the system for a triangular velocity waveform is investigated in the measurement of Mossbauer spectra of standard sample(αFe, αFe₂O₃, stainless steel and Na₂[Fe(CN)_(5)NO]₂H₂O). The system is stabilized and the linearity of the system for triangular velocity waveform is better than ?0.01% for the half-period of 14mm/sec velocity.

발전플랜트에서의 Engineering IT 적용 특성 및 추진 전략 고찰

남신영(S.Y. Nam),양인수(I.S. Yang),김용백(Y.B. Kim),최성균(S.K. Choi),안재순(J.S. Ahn) (사)한국CDE학회 2007 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2007 No.1

초미세결정립 Fe73.5Cu₁Nb₃Si16.5B6 합금의 Mossbauer 효과 연구

신영남(Young Nam Shin),김재경(Jae Gyeung Kim),양재석(Jae Suk Yang),조익한(Ick Han Cho),강신규(Sin Giu Kang) 한국자기학회 1994 韓國磁氣學會誌 Vol.4 No.1

The crystallization behavior of the amorphous Fe_(73.5)Cu₁Nb₃Si_(16.5)B_6 alloy with isothermal annealing at 552 ℃ was studied by Mossbauer spectroscopy. The amorphous phase was revealed to coexist together with DO₃-FeSi nanocrystalline and Cu-duster in annealed alloys by Mossbauer spectrum analysis. At the early stage of crystallization, Si content of FeSi is high due to the creation of Cu-cluster, and decreases with annealing until 60 minutes, which results in the increase in the mean hyperfine field of FeSi, and thereafter keeps constant. After 60 minutes, the decrease in the mean hyperfine field of the residual amorphous, in spite of a slight change in the volume fraction of the FeSi and the residual amorphous, is caused by the increase in the content of Nb and B in residual amorphous phase. Both directions of the hyperfine field, those of the FeSi and the residual amorphous, become randomly oriented in about 60 minutes. For FeSi and Cu-duster, the Avrami exponents are 0.51 and 0.65, the activation energies are 2.35 eV and 2.44 eV, and the incubation times are 2.4 minutes and 0.8 minutes respectively. Earlier formation of Cu-duster than that of FeSi is coincidence with the fact that Cu atom promotes the nucleation of the FeSi.

Soda 유리에 있어서 鐵이온의 Mössbauer效果

신영남,박성배,김재경,오재환 대구대학교 산업기술연구소 1984 産業技術硏究 Vol.3 No.-

Mössbauer studies of a large number of glass samples prepared with alkali oxides in the region of glass formation are reported. In this study amorphous soda glasses were prepared with 4 mole% of ferric oxide as impurity. Mössbauer parameters and the valance state of iron in soda glasses were studied by Mössbauer spectra. X Na₂O·(100-X)B₂O₃·4Fe₂O₃ where X=10, 20 or 30 mole%, were prepared, and 10 A₂O·90 B₂O₃·4 Fe₂O₃ where A=Li, Na or K mole% were prepared for the study of the change with the ionic radii of alkali glasses. Mixtures were melted in air atmosphere in furnance at 900℃ for two hours. Mössbauer absorption measurements have been at room temperature. The γ-ray source is 3 mCi Co^(57) doped in Pd. In soda glasses isomer shift and quadrupole splitting were decreased according to increasing of X component and line width was increased. Isomer shift was increased, but quadrupole splitting and line width were decreased along the Li-Na-K series.

Potassium 유리에 있어서 鐵이온의 Mossbauer Spectrum에 關한 硏究

신영남,박성배 大邱大學校附設 基礎科學硏究所 1984 基礎科學硏究 Vol.1 No.-

Mossbauer studies of a large number of glass samples prepared with alkali oxides in the region of glass formation have been reported. In this study amorphous potassium borate glasses with ferric oxides as impurity were prepared. By Mossbauer spectra Mossbauer parameters, the valence state and coordinate of iron doped in potassium borate glassess were studied. The base composition of potassium borate glasses containing ferric oxide was as follow; X%K₂0(100-X) %B₂0₃Y%Fe₂0₃, where X is 10, 20 or 30 mole % and Y is 4, 6 or 8 mole%. These mixtures were melted in furnace at 900℃ for two hours under air atmosphere. The r-ray source is 10 mCi Cou. Experiments have been performed at room temperature. Isomer shift values and quadrupole splitting values decrease gradually with the addition of alkali or ferric oxide. We conclude that iron is in ferric state from spectra and the oxygen polyhedra of ion changes from octahedral to tetrahedral. i

Mössbauer 效果와 그 應用에 關한 硏究

신영남 대구대학교 (한사대학) 산업기술연구소 1982 産業技術硏究 Vol.2 No.1

Mössbauer effect is that γ-ray is radiated and absorbed from neuclear in the recoilless process. Mössbauer spectroscopy as a microscopic method has become important for elucidating the atomic arrangements and magnetic structures of the matterials. The magnitude of the hyperfine pattern is important with regard to the atomic structure, while the angular dependence of the hyperfine pattern gives information on the orientation of the spin. Mössbauer effect is applicated in various field of natural science. Specialy, its use is very important for physicists, chemists, biologists, mineralogists, metallurgists and engineers.

CuO·V₂O_(5)·Fe₂O₃ 유리계의 Mossbauer 효과에 관한 연구

申榮男,李熙英 大邱大學校附設 基礎科學硏究所 1988 基礎科學硏究 Vol.5 No.-

The Mossbauer parameters, the valence state and the site of Fe ions in the xCuO·(1--x-y) V₂O_(5)·yFe₂O₃ glasses where x is O. 15, 0.20, 0.25 and 0.30 mole ratio and y is 0.12, 0.15 and 0.18 mole ratio have been studied by the Mossbauer spectroscopic method at room temperature. The samples are gotten by melting at 1200℃ for 3 hours and quenching in water and are revealed a glassy structure by the X-ray diffraction. The source of γ-ray is 5m Ci ^(57)o doped in rhodium. The observed pair of asymmetric lines suggest that Fe^(3+) ions exist both at octahedral and tetrahedral sites. There is no evidence of the presence of Fe^(2+)ions and Zeeman hyperfine spilitting. The addition of CuO increases the number of Fe^(3+) ions at the tetrahedral sites. The isomer shift increases with increasing CuO, which diminishes 4s electron density at both the octahedral and tetrahedral sites of iron nucleus. The quadrupole splitting decreases with increasing CuO, which changes the symmetry around the octahedral and tetrahedral sites of the iron ions. The isomer shift range of octahedral coordination is 0.261-0.290 mm/sec and that of tetrahedral coordination is 0.239-0.304 mm/sec. The quadrupole splitting for octahedral site ranges from 0.600 mm/sec to 0.749 mm/sec and that for tetrahedral sites ranges from 1.009 mm/sec to 1.274 mm/sec.

Fe-Ge 화합물에 대한 Mossbauer효과

신영남,김재경,안범수 大邱大學校附設 基礎科學硏究所 1989 基礎科學硏究 Vol.6 No.-

Fe-Ge intermetalIic compounds were prepared as follows : the mixtures of Fe and Ge powder at the mole ratio of 1:1, 2:1 and 3:1 were melted at 1050℃ in the vaccum(10­³torr) for 50 hours and sintered at 650℃ for FeGe and at 850℃ for Fe₂Ge and Fe5Ge for 52 hours and then quenched in water. The crystal structures and internal magnetic fields of Fe-Ge intermetallic compounds were investigated by X-ray diffraction and Mossbauer spectroscopy. Mossbauer spectra of powdered samples were obtaind using a 57 Co/Rh source at room temprature. The values of internal magnetic fields of FeGe and Fe2Ge were 119.3 k0e and 238.3 k0e, respectively. And those of Fe2Ge were 127.2kOe, 185.1 k0e and 237.7kOe. The crystal structures of FeGe, Fe₂Ge and Fe₃Ge were hexagonal B35, B8₂, DO_(19), types, respetively.

YBa₂(Cu_(1-x)Fe_(x))₃O_(9-y)계의 초전도성과 Mossbauer 효과

申榮男,金在慶,조현웅 大邱大學校附設 基礎科學硏究所 1990 基礎科學硏究 Vol.7 No.-

YBa₂(Cu_(1-x)Fe_(x))₃O_(9-y) superconductors are prepared and their physical characteristics are investigated by measuring the resistivity, X-ray diffraction pattens and Mossbauer spectra. At x=0.03, the crystal structure is transformed from orthorhombic to tetragonal system. Transition temperatures are not changed in the orthorhombic region, but linealy decreased with increasing x in the tetragonal region (80K at x=0.03 and 30K at x=0.1). The Mossbauer spectra are fitted to Lorentzian line shapes with two quadrupole doublets. Two main doublets and lattice parameters indicate that the valancy of Fe is +3. F2 site has typical square-pyramid coordination and F1 site has highly atypical (for Fe^(3+)) coorination of square-planar.