• Journal of Astronomy and Space Sciences
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• 제9권2호
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• pp.143-153
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• 1992

Spectra of the $\zeta$ Aurigae type eclipsing binary system 32 Cygni were taken at the Asiago Observatory. Using the Gaussian fitting method we can estimate the radial velocity and equivalent widths of some metalic lines.

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 하계학술발표회
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• pp.292-293
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• 2001

• 약학회지
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• 제5권1호
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• pp.3-5
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• 1960

Trace elements in deer horn have been determined Ca, Mg, Fe, Cu, Zn, Mn, Al and as were detected by partition paper chromarography and spectroscopic method.

• 약학회지
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• 제45권5호
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• pp.455-459
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• 2001

Melandrii Herba has been used for tympanitis, sore throat, dysentery and dehumidifying diuretic. From the BuOH fraction of methanol extracts, three ecdysteroids (ecdysterone, ecdysterone 22-acetate and inokosterone) were isolated by column chromatography using Amberlite XAD-4, ODS and Sephadex LH-20 gel and by HPLC method. The structures of these compounds were identified on the basis of spectroscopic methods.

• 약학회지
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• 제60권2호
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• pp.85-91
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• 2016

Drying of granules for tablet formulation is one of the important unit operations. The loss on drying method is traditionally used for this purpose. However, it is a time-consuming method, requiring at least 1 h. Moreover, it is ineffective in monitoring the moisture content of granules during the drying process. In this study, online real-time monitoring of moisture content during the drying process was successfully performed using near-infrared (NIR) spectroscopy. NIR spectra were collected during 15 different drying batches for developing a reliable NIR spectroscopic method. Such a large number of batches were used to develop a more robust partial least squares (PLS) model. NIR spectra collected from 12 batches were used for developing the model that was validated by predicting the moisture content of the samples in the remaining 3 batches. The standard errors of predictions (SEPs) in the measurement of batch 1, batch 2, and batch 3 were 0.52%, 0.57%, and 0.56%, respectively. The online NIR spectroscopic method developed in this study was reliable and accurate in monitoring the moisture content during the drying process.

• 분석과학
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• 제15권4호
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• pp.341-345
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• 2002

UV 광 중합 반응의 진행정도를 near-IR 분광학적 방법을 사용하여 관찰하였다. 광중합반응의 반응체는 4차 암모늄염을 포함하고 있는 아크릴 모노머를 사용하였으며 광 개시제로는 Darocur 1174를 사용하였다. 반응의 진척도는 광중합 반응의 정도를 나타내 주는 척도가 되는 중합 반응체인 아크릴 모노머의 -C=$CH_2$ 기와 관련된 흡수 띠인 1615 nm(6190 $cm^{-1}$)와 2105 nm(4750 $cm^{-1}$)에서 관찰된 띠 세기의 전환율로부터 구하였다. Near-IR 분광법이 광 중합 반응의 진행정도를 관찰하는데 효과적인 방법이 될 수 있음을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제24권12호
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• pp.1785-1792
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• 2003

Zirconia modified with $MoO_3$ was prepared by impregnation of powdered $Zr(OH)_4$ with ammonium heptamolybdate aqueous solution followed by calcining in air at high temperature. Spectroscopic studies on prepared catalysts were performed by using FTIR, Raman, XRD, and DSC and by measuring surface area. Upon the addition of molybdenum oxide to zirconia up to 15 wt%, the specific surface area increased in proportion to the molybdate oxide content, while acidity measured by irreversible chemisorption of ammonia exhibited a maximum value at 3 wt% of $MoO_3$. Since the $ZrO_2$ stabilizes the molybdenum oxide species, for the samples equal to or less than 30 wt%, molybdenum oxide was well dispersed on the surface of zirconia and no phase of crystalline $MoO_3$ was observed at any calcination temperature above $400^{\circ}C$. The catalytic activities for cumene dealkylation were roughly correlated with the acidity of catalysts measured by ammonia chemisorption method, while the catalytic activities for 2-propanol dehydration were not correlated with the acidity because weak acid sites are necessary for the reaction.

• 천문학회보
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• 제44권1호
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• pp.56.2-56.2
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• 2019

Measurement of the location of the baryon acoustic oscillation (BAO) feature in the clustering of galaxies has proven to be a robust and precise method to measure the expansion of the Universe. The best constraints so far have been provided from spectroscopic surveys because the errors on the redshift obtained from spectroscopy are minimal. This in turn means that the errors along the line-of-sight are reduced and so one can expect constraints on both angular diameter distance $D_A$ and expansion rate $H^{-1}$. But, future surveys will probe a larger part of the sky and go to deeper redshifts, which correspond to more number of galaxies. Analysing each galaxy using spectroscopy, which is a time consuming task, will not be practically possible. So, photometry will be the most convenient way to measure redshifts for future surveys such as LSST, Euclid, etc. The advantage of photometry is measuring the redshift of vast number of galaxies in a single exposure, but the disadvantage are the errors associated with the measured redshifts. Using a wedge approach, wherein the clustering is split into different wedges along the line-of-sight ${\pi}$ and across the line-of-sight ${\sigma}$, we show that the BAO information can be recovered even for photometric catalogues with errors along the line-of-sight. This means that we can get cosmological distance constraints even if we don't have spectroscopic information.

• 반도체디스플레이기술학회지
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• 제20권3호
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• pp.178-183
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• 2021

This paper describes a dynamic spectroscopic ellipsometry based on dual-wavelength calibration. DSE provides ellipsometric parameters at rates above 20 Hz, but the interferometer's sensitivity to temperature makes it difficult for that proposed system to maintain stable 𝜟k over long periods of time. To solve this problem, we set up an additional path in the DSE to perform simulations of the polarization phase calibration method using dual wavelengths. Through simulation, we were able to eliminate most of the polarization phase error and maintain a stable 𝜟k in the long-term stability experiment for 10 hours. This is the result that the 𝜟k stability of the proposed system is improved tens of times compared to the existing system.

• 생태와환경
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• 제56권4호
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• pp.339-347
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• 2023

본 연구는 TOC/TN-IRMS를 이용하여 총 유기탄소 및 총 질소 안정동위원소 분석법을 연구하였으며, 수환경 중저농도 시료에서도 분석이 가능하게 시스템을 구축하였다. 수생태계로 유입되는 다양한 유기탄소 기원을 파악하기 위하여 형광지표와 δ¹³C-DOC 안정동위원소비를 활용한다면 효율적인 수질 관리를 위한 해석기능을 제공할 것이며, 추후 유역 오염원의 대표값(end member)의 지속적인 조사를 통하여 자료구축이 이루어져야 할 것이다.