• 한국진공학회지
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• 제2권4호
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• pp.486-490
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• 1993

Cd4SnSea6 & Cd4SnSe6 : Co2+ single crystals were grown by the chemical transport reaction (CTR) method. The grown single crystlas crrystallize in the monoclinic structrue and have the direct band gaps. The energy gaps of them are 1.68eV for Cd4SnSea6 & Cd4SnSe6 : Co2+ at 293K. The impurity opticla absorption peaks due to cobalt dped with impurity appear at 4879cm-1, 5392cm-1 and 6247 com-1, and are attributed to the electron transitions between the split energy levels of Co2+ ion sited at Td symmetry of Cd4SnSe6 single crystal.

• 한국진공학회지
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• 제3권2호
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• pp.227-233
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• 1994

CuAlGeSe4 및 CuAlGeSe4 ; Co2+ 결정을 고순도의 성분원소로부터 합성하고 서냉법으로 결정을 성장시켰다. 이들결정은 chalcopyrite 결정구조를 갖고 있으며 직접전이형 energy gap 구조를 갖고 286K에서 energy gap은 CuAlGeSe4 결정의 경우는 2.394eV이며 CuAlGeSe4 ; Co2+ 결정의 경우는 2.302 eV로 주어졌다. CuAlGeSe4 : Co2+ 결정에서 cobalt에 의한 불순물 광흡수 peak들은 12243, 7002, 3890 cm-1에서 나타났으며 이 peak들은 CuAlGeSe4 : Co2+ 결정의 Td symmetry site에 위치한 Co2+ ion의 energy 준위사이의 전자전이에 의한 optical absorption임을 규명했다.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 추계 총회 및 학술발표회
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• pp.99-102
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• 2004

• 약학회지
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• 제22권1호
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• pp.27-32
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• 1978

Metoclopramide reacts with ammonium cobaltothiocyanate to form a stable ion pair which has an absorption maximum of 625mm. The reaction product was insoluble in water but soluble in most organic solvents. 1,2-Dichlorethane was the best extracting solvent among the several organic solvents tested. Metoclopramide can be determinded not only by visible light spectrophotometry but also indirectly by estimation of cobalt in the organic phase by flameless atomic absorption spectrophotometry. Linear relationship was found between absorbance and concentration in the range of 10$^{-4/}$-10$^{-3}$M by spectrophotometry and 10$^{-5}$-10$^{-4}$M by flameless atomic absorption spectrophotometry. The coefficient of variation by spectrophotometry was 0.9% and that of flameless atomic absorption was 1.8%. There was no interference with excipients, pH, temperature and reaction time. With this method, it is possible to determine accurately metoclopramide and tertiary amines in pharmaceutical preparations.

• 대한화학회지
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• 제7권1호
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• pp.34-37
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• 1963

Cobalt(Ⅲ) ion gives two step waves with $E_{1/2}$－0.1V(?)(vs.S.C.E.) and $E_{1/2}$－1.37V(vs. S.C.E.) from a base electrolyte consisting of 0.1 M TEA＋sodium borate＋0.0002% gelatin. The first wave results from the reduction Co(Ⅲ) to Co(Ⅱ). The second wave corresponding to the reduction Co(Ⅱ) to Co(0) and this wave is diffusion controlled. The diffusion current constant of the second wave is 2.7. Under these-conditions, diffusion current of the second wave is proportional to the concentration of Co (Ⅱ) in the range of $10^{-3}{\sim}10^{-4}$ M.

• 대한화학회지
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• 제13권4호
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• pp.309-312
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• 1969

A series of metal ion-2, 5-diamine 1, 4-dihydroxybenzene polymers containing copper(II), nickel(II) or cobalt (II) have been prepared. The structure was postulated on the basis of elementary analysis of polymers. It was found that copper polymer is most likely the coordination polymers by X-ray powder pattern studies. The thermal stability of the polymers was also studied by a simple method, utilizing a thermogravimetric balance. The order of thermal stabilities is Cu(II) > Ni(II) > Co(II). The polymers start to decompose at a relatively low temperature.

• 한국환경과학회지
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• 제11권2호
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• pp.131-137
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• 2002

The chemical behavior and properties on the redox state of environmental pollutant has been investigated by electrochemical methods. We carried out to measure the variations in the redox reaction of differential pulse polarogram and cyclic voltammogram. The results observed the influences on redox potential and current of various factors with temperature and pH. These were established factors as the effect of the redox reaction. It can be clearly recognized that the electrode reaction are from qusi-reversible to irreversible processes. Also, it was mixing with reaction current controlled. The bits-phenol A in the waste water was made to compound with cobalt ion and it take away from the separation into compound. The $Co(BPA)_2$ compound was not found to be dissociation in waste water. However, this compound is avery unstable(K=1.02) and for a while, it was to be a dissociation. Therefore, we believed that it was likely to a toxic substance.

• 약학회지
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• 제27권4호
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• pp.303-307
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• 1983

Pipethanate*HCl reacts with ammonium cobaltothiocyanate to form a stable ion pair which has an absorption maximum at 626nm. The reaction product was insoluble in water but freely soluble in most organic solvents. 1, 2-Dichloroethane was the best extracting solvent among the several organic solvents. Pipethanate*HCl can be determined not only by the spectrophotometry but also inderectly by estimation of cobalt in the organic phase by atomic absorption spectrophotometry. Linear relationship was found between absorbance and concentration in the range of $1.0{\times}10^{-3}~4.0{\times}10^{-3}M$ by spectrophotometry and $1.5{\times}10^{-4}~4.0{\times}10^{-4}M$ by atomic absorption spectrophotometry. With this method it was possible to determine pipethanate$\cdot$HCl in the pharmaceutical preparations.

• 한국산학기술학회논문지
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• 제4권1호
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• pp.17-21
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• 2003

산업용 뿐만 아니라 보석용으로 가치가 있는 합성 및 천연사파이어를 인위적으로 청색발색효과를 높이기 위해 확산 처리한 경우, 종래 육안감정에 의해서는 확산처리 유무 및 불순물 주입 정도에 따른 광학적 특성의 감정이 어려운 문제가 있었다. 비파괴적이고 빠른 시간안에 정량적인 분석을 위해 FTIR(Fourier transformation infra-red) 분석을 이용하여 해결할 수 있음을 확인하였다. 기존의 고가 SIMS(secondary ion mass spectrometry) 등 고가 진공분석장비에 비하여 획기적으로 3분 이내의 분석을 통하여 경제적, 비파괴적인 분석이 가능하여, 관련 업체에 도입되는 경우 제안된 전용 FTIR 설비를 이용하여 처리사파이어의 정밀감정이 가능하였다.

• 한국전기전자재료학회논문지
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• 제13권7호
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• pp.557-562
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• 2000

160nm thick amorphous Si and polycrystalline Si were each deposited on to 10nm thick SiO$_2$, Co monolayer and Co/Ti bilayer were sequentially evaporated to form Co-polycide. Then MOS capacitors were fabricated by BF$_2$ ion-implantation. The characteristics of the fabricated capacitor samples depending upon the drive-in annel conductions were measured to study the effects of thermal stability of CoSi$_2$and dopant redistribution on electrical properties of Co-polycide gates. Results for capacitors using Co/Ti bilayer and drive-in annealed at 80$0^{\circ}C$ for 20~40sec. showed excellent C-V characteristics of gate electrode.