• 제목/요약/키워드: spectroscopic determination

검색결과 153건 처리시간 0.032초

근적외 분광분석법에 의한 분말고추중의 씨앗 및 꼭지혼입량의 신속한 측정 (Rapid Determination of Seed and Stem Content in Red Pepper Powder by Near-Infrared Reflectance Spectroscopic Analysis)

  • 조래광;손미령;안재진
    • 한국식품과학회지
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    • 제23권4호
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    • pp.447-451
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    • 1991
  • 분말고추가루에 씨앗이나 꼭지를 혼입시켜 저장시킨 결과 capsanthin, capsaicin, total-sugars 등의 성분이 감소되었으며 특히 꼭지가 혼입된 시료보다 씨앗이 혼입된 시료에 있어서 품질의 열화정도가 큼을 알 수 있었다. 이와 관련하여 씨앗이나 꼭지의 함량을 근적외 분광분석법으로 측정할 수 있는지의 가능성을 조사한 결과 씨앗의 혼입량은 1.76%의 측정오차로, 꼭지의 혼입량은 0.43%의 측정오차로 각각 30초 이내에 통시 측정할 수 있음을 확인하였다.

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Spectroscopic Techniques for Nondestructive Quality Inspection of Pharmaceutical Products: A Review

  • Kandpal, Lalit Mohan;Park, Eunsoo;Tewari, Jagdish;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
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    • 제40권4호
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    • pp.394-408
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    • 2015
  • Spectroscopy is an emerging technology for the quality assessment of pharmaceutical samples, from tablet manufacturing to final quality assurance. The traditional methods for the quality management of pharmaceutical tablets are time consuming and destructive, while spectroscopic techniques allow rapid analysis in a non-destructive manner. The advantage of spectroscopy is that it collects both spatial and spectral information (called hyperspectral imaging), which is useful for the chemical imaging of pharmaceutical samples. These chemical images provide both qualitative and quantitative information on tablet samples. In the pharmaceutics, spectroscopic techniques are used for a variety of applications, such as analysis of the homogeneity of powder samples as well as determination of particle size, product composition, and the concentration, uniformity, and distribution of the active pharmaceutical ingredient in solid tablets. This review paper presents an introduction to the applications of various spectroscopic techniques such as hyperspectroscopy and vibrational spectroscopies (Raman spectroscopy, FT-NIR, and IR spectroscopy) for the quality and safety assessment of pharmaceutical solid dosage forms. In addition, various chemometric techniques that are highly essential for analyzing the spectroscopic data of pharmaceutical samples are also reviewed.

Mid-Infrared Luminosity Function of Local Galaxies in the North Ecliptic Pole Region

  • 김성진;이형목
    • 천문학회보
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    • 제38권1호
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    • pp.38.1-38.1
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    • 2013
  • We present observational estimation of the infrared (IR) luminosity function (LF) of local (z < 0.3) star-forming (SF) galaxies derived from the AKARI NEP-Wide samples. We made an analysis of the NEP-Wide data with optical spectroscopic information allowing an accurate determination of luminosity function. Spectroscopic redshifts for about 1650 objects were obtained with MMT/Hectospec and WIYN/Hydra, and the median redshifts is about 0.22. To measure the contribution of SF galaxies to the luminosity function, we excluded AGN sample by comparing their SEDs with various model template. Spectroscopic redshifts and the AKARI's continuous filter coverage in the mid-IR (MIR) wavelength (2 ~ 25 micron) enable us to avoid large uncertainties from the mid-IR SED of galaxies and corresponding k-corrections. The 8-micron luminosity function shows a good agreement with the previous works in the bright-end, whereas it seems not easy to constrain the faint-end slope. The comparison with the results of the NEP-Deep data (Goto et al. 2010) suggests the luminosity evolution to the higher redshifts, which is consistent with the down-sizing evolutionary pattern of galaxies.

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Determination of the Optical Functions of Various Liquids by Rotating Compensator Multichannel Spectroscopic Ellipsometry

  • Bang, Kyung-Yoon;Lee, Seung-Hyun;Oh, Hye-Keun;An, Il-Sin;Lee, Hai-Won
    • Bulletin of the Korean Chemical Society
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    • 제26권6호
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    • pp.947-951
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    • 2005
  • Rotating compensator multichannel spectroscopic ellipsometry has been employed to determine the optical functions of various liquids used in chemistry. We attempted three different measurement configurations: (1) air-liquid interface, (2) prism-liquid interface, and (3) liquid-sample interface. In prism-liquid interface, we found that the prism surface had roughness and it should be considered in analysis for accurate results. In liquidsample interface, we had much higher reflection, better sensitivity, and less limitation compared to the other two configurations when crystalline silicon was used as reference sample. We discuss the merit of each configuration and present the optical functions of various liquids. Also we demonstrate Bruggeman effective medium theory to determine the optical properties of mixed liquid.

ISOTOPIC-SPECTRAL DETERMINATION OF CARBON IN HIGH PURITY INORGANIC MATERIALS

  • Lee, V.N.;Nemets, V.M.
    • 분석과학
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    • 제8권4호
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    • pp.477-480
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    • 1995
  • Isotopic-spectral method [I] was applicated for determination of carbon in silicate materials (pure silica, guartz glasses, geological probs etc.). Isotopic heterogeneous balancing of carbon in gaseous phase and solid samples was carried out at the temperature of $1500-1900^{\circ}K$. Spectroscopic measuring of isotope concentration in a balanced gas was made using the electron-vibrational band heads of CO molecules excited in HF discharge. Limits of detection of carbon concentrations appear to be $n^*10^{-6}$.

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Adsorption Kinetics for Polymeric Additives in Papermaking Aqueous Fibrous Media by UV Spectroscopic Analysis

  • Yoon, Sung-Hoon;Chai, Xin-Sheng
    • Bulletin of the Korean Chemical Society
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    • 제27권11호
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    • pp.1819-1824
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    • 2006
  • The general objective of the present study was to investigate the potential application of the UV spectroscopic method for determination of the polymeric additives present in papermaking fibrous stock solutions. The study also intended to establish the surface-chemical retention model associated with the adsorption kinetics of additives on fiber surfaces. Polyamide epichlorohydrin (PAE) wet strength resin and imidazolinium quaternary (IZQ) softening agents were selected to evaluate the analytical method. Concentrations of PAE and IZQ in solution were proportional to the UV absorption at 314 and 400 nm, respectively. The time-dependent behavior of polymeric additives obeyed a mono-molecular layer adsorption as characterized in Langmuir-type expression. The kinetic modeling for polymeric adsorption on fiber surfaces was based on a concept that polymeric adsorption on fiber surfaces has two distinguishable stages including initial dynamic adsorption phase and the final near-equilibrium state. The simulation model predicted not only the real-time additive adsorption behavior for polymeric additives at high accuracy once the kinetic parameters were determined, but showed a good agreement with the experimental data. The spectroscopic method examined on the PAE and IZQ adsorption study could potentially be considered as an effective tool for the wet-end retention control as applied to the paper industry.

가변입사각 분광타원 법을 이용한 유기 발광 박막의 광학상수 및 두께 결정 (Determination of optical constants and thickness of organic electroluminescence thin films using variable angle spectroscopic ellipsometry)

  • 김상열;류장위;김동현;정혜인
    • 한국광학회지
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    • 제12권6호
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    • pp.472-478
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    • 2001
  • 가변입사각 분광타원법(Variable Angle Spectroscopic Ellipsometry)을 사용하여 유기발광소자(OLED)의 발광층인 유기박막 의 광학상수와 두께를 결정하였다. 광투과영역에서 모델링분석으로 박막의 평균두께와 굴절률 분산식을 결정하고, 광흡수영역으로 확장하여 유기막의 다층구조, 각 층의 두께와 밀도 그리고 각 파장에서의 복소굴절률을 결정하였다. 분광광도계를 사용하여 구한 투과율 스펙트럼을 가변입사각 분광타원법을 사용하여 결정한 다층구조 및 복소굴절률로 계산한 투과율 스펙트럼과 비교하여 분석의 정확성을 확인하였다.

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