• Journal of Photoscience
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• 제11권3호
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• pp.95-99
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• 2004

Optical absorption and emission studies have been carried out to understand the effect of deuterium on the solvent dependent photophysical properties of curcumin in deuterated solvents such as $CDCl_3,\;(CD_3)_2SO,\;(CD_3)_2CO,\;CD_3OD\;and\;CD_3CN$. Optical absorption spectral studies showed that there is no significant shift in absorption maxima compared to the non-deuterated solvent. The fluorescence maxima shows significant shift with polarity of solvent but not much affected by the deuteration. The fluorescence quantum yield of curcumin increased marginally in almost all the deuterated solvents, indicating reduction in the non-radiative pathways. The fluorescence decay was biexponential in all the solvents and the average fluorescence lifetime was not much affected with deuteration, but showed decrease with increasing solvent polarity. Based on these studies, it is concluded that intermolecular hydrogen transfer is only partially responsible for the excited state deactivation of curcumin.

• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2732-2736
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• 2011

In pH 4.2 HAc-NaAc buffer solution, horseradish peroxidase (HRP) catalyzed $H_2O_2$ oxidation of nanosilver to form $Ag^+$. After centrifugation, $Ag^+$ in the supernatant can be measured by graphite furnace atomic absorption spectrophotometry (GFAAS) at the silver absorption wavelength of 328.1 nm. When HRP concentration increased, the $Ag^+$ concentration in the supernatant increased, and the absorption value enhanced. The HRP concentration in the range of 0.84-50 $ng{\cdot}mL^{-1}$ was linear to the enhanced absorption value (${\Delta}A$), with a regression equation of ${\Delta}A$=0.012C+0.11, correlation coefficient of 0.9988, and detection limit of 0.41 $ng{\cdot}mL^{-1}$ HRP. The proposed GFAAS method was used to detect HRP in waste water samples, with satisfactory results.

• 분석과학
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• 제8권4호
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• pp.443-448
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• 1995

Three anode configurations of six-jet, cone-jet and cylindrical-jet are tested for their analytical performance under power mode operation. The effect of pressure, power and gas flow rate on atomic absorption signals have been studied. The increase of atomic absorption signal of sample element is observed at a fixed pressure in all configurations as the gas flow rate increase up to 300-600 seem, and as the power dissipated in the glow discharge cell increase. The lower the pressure is in the glow discharge cell at a fixed discharge power and argon flow rate, the greater the absorbance of sample element is. The optimum conditions are taken from these data and a calibration curve of Cu in low-alloy steel sample is obtained. In this calibration curve, six-jet configuration shows the best analytical results varies as the sample element.

• 분석과학
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• 제5권2호
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• pp.185-190
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• 1992

글로우방전장치를 기존의 원자흡수분광기의 버너 대신에 장착하였다. 정확도를 측정하기 위하여 철강표준물질을 이용하여 측정된 값과 농도를 비교하였다. 검정곡선을 작성하였으며 작성된 검정곡선으로 원자흡광감고를 측정하였다. 감도에 영향을 미치는 인자들 및 개선된 장치의 개발에 필요한 분야에 관하여 연구하였다.

• 약학회지
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• 제40권5호
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• pp.501-506
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• 1996

This study was conducted to investigate on the changes of copper and zinc concentration in rat's tissues and urine after cadmium administration with atomic absorption spectroph otometric method. It is found that cadmium appeared to cause a change in the behavior of copper and zinc in vivo system even during 1 month after cadmium treatment.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2012년도 춘계학술논문요약집
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• pp.103-104
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• 2012

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.164-164
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• 2000

Since Au-Pt alloys have various atomic structures depending upon composition and annealing temperature, it is very interesting to investigate the electronic structures of alloys. We studied the changes of the electronic structure I the Au-Pt alloys by x-ray absorption near edge spectroscopy (XANES). Two kinds of Au-Pt alloy samples were prepared by arc melting methods and ion-beam-mixing technique. The Pt L2, 3-edge and Au L2, 3-edge X-ray absorption spectra (XPS) were measured with the electron yield mode detector at the 3C1 beam line of the Pohang Light Source (PLS). It was found that there was a substantial decrease in the area of the Pt L2, 3 white lines compared with that of pure Pt. The observed decrease in white line area was attributed to an increase in the number of pure Pt. The observed decrease in white line area was attributed to an increase in the number of 5d-electrons at the Pt site upon alloy formation. However, the Au L2, 3 edge spectra for Au-Pt alloys are all similar to that of pure Au. This implies that the 5d hole count of Au is not changed by alloy formation with Pt.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 춘계학술발표회요약집
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• pp.33-33
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• 1999

• 분석과학
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• 제6권4호
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• pp.359-362
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• 1993

원자흡수분광법으로 여러 원소를 동시분석시 최적 조건을 위하여 연료의 종류, 연료의 양 및 버너 높이의 변화에 대해 10가지 원소의 흡광도를 측정하였다. Air-$C_2H_2$를 연료로 과량을 사용하고, 버너 높이가 2mm일 때 최적 흡광도를 나타내었고, 이때 10가지 원소의 상대흡광도의 평균은 73%였다.

• 한국식품영양과학회지
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• 제10권1호
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• pp.107-116
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• 1981

This experiment was attempted to establish the optimal condition, e.g., the effects of pH, interferences of other elements, for the determination of the inorganic elements in the paddy soils by atomic absorption spectrophotometry. Inorganic elements of 100 paddy soils which were sampled in Jeon bug provincial farm land were determined by atomic absorption spectrophotometer in that condition. The results obtained in this experiment are summarized as follows: 1) The optimal pH for determination of inorganic elements in paddy soils is about 7.0. 2) It was investigated that the absorbance of potassium was increased, and that of calcium, magnesium and zinc was decreased by adding of $Fe^{++}$ and $Cu^{++}$ in the sample. 3) It was shown that paddy soils in Jeonbug provincial farm land contain the normal amounts of inorganic elements (K, Ca, Mg, Zn,). But comparing to the results of 1976 year, it was known that the contents of inorganic elements in paddy soils considerably was changed.