• 제목/요약/키워드: Spectroscopy

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A Novel Classification of Polymorphs Using Combined LIBS and Raman Spectroscopy

  • Han, Dongwoo;Kim, Daehyoung;Choi, Soojin;Yoh, Jack J.
    • Current Optics and Photonics
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    • 제1권4호
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    • pp.402-411
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    • 2017
  • Combined LIBS-Raman spectroscopy has been widely studied, due to its complementary capabilities as an elemental analyzer that can acquire signals of atoms, ions, and molecules. In this study, the classification of polymorphs was performed by laser-induced breakdown spectroscopy (LIBS) to overcome the limitation in molecular analysis; the results were verified by Raman spectroscopy. LIBS signals of the $CaCO_3$ polymorphs calcite and aragonite, and $CaSO_4{\cdot}2H_2O$ (gypsum) and $CaSO_4$ (anhydrite), were acquired using a Nd:YAG laser (532 nm, 6 ns). While the molecular study was performed using Raman spectroscopy, LIBS could also provide sufficient key data for classifying samples containing different molecular densities and structures, using the peculiar signal ratio of $5s{\rightarrow}4p$ for the orbital transition of two polymorphs that contain Ca. The basic principle was analyzed by electronic motion in plasma and electronic transition in atoms or ions. The key factors for the classification of polymorphs were the different electron quantities in the unit-cell volume of each sample, and the selection rule in electric-dipole transitions. The present work has extended the capabilities of LIBS in molecular analysis, as well as in atomic and ionic analysis.

Bromosulfophthalein의 체내동태 평가에 미치는 분석법의 영향: HPLC 법과 UV 흡광광도법의 비교 (Effect of Analytical Method on the Pharmacokinetic Evaluation of Bromosulfophthalein: Comparison of HPLC and UV Spectroscopy Method)

  • 오주희;차유경;이영주
    • Journal of Pharmaceutical Investigation
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    • 제38권6호
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    • pp.399-403
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    • 2008
  • The aim of this study was to evaluate the difference of analytical methods for the pharmacokinetic study of bromosulfophthalein (BSP), an indicator of hepatobiliary function. The plasma and bile concentrations of BSP after intravenous administration were measured according to custom UV spectroscopy and HPLC, respectively. Plasma concentration of BSP measured by UV spectroscopy was similar to that measured by HPLC. There was no significant difference in the distribution volume, total body clearance, area under the curve and mean residence time of BSP between different analytical method groups. However, bile concentration of BSP measured by UV spectroscopy was overestimated compared with concentration measured by HPLC method. Biliary clearance of BSP obtained from UV spectroscopy method was almost 3 times higher than that obtained from HPLC method. Thus, a feasibility of UV spectroscopy method for high throughput pharmacokinetic evaluation of BSP was limited to the study based on the plasma concentration of BSP, not bile concentration.

초음파 Spectroscopy에 의한 Resin내의 크기 측정에 관한 연구

  • 한응교;김용재;이범성;박익근;소반신부
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 추계학술대회 논문집
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    • pp.139-143
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    • 2001
  • In manufacturing process of semiconductor package, thermal stress owing to high temperature in moulding and bubbles generated in chip bonding process become main causes to producing void. Therefore, on this study we evaluated quantitatively void size by ultrasonic spectroscopy method which analyze the frequency of this received pulse using pulses with broad band frequency, and after destructive test we verified effectiveness of sizing void by ultrasonic spectroscopy as we find error degree between the real size of void and the sizing void by ultrasonic spectroscopy.

초음파 분량법에 의한 레진 내부 결합의 크기 측정에 관한 연구 (Sizing of lnner Flaw in Resin by using Ultrasonic spectroscopy)

  • Han, E.K.;Kim, Y.J.;Park, I.G.
    • 한국정밀공학회지
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    • 제10권3호
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    • pp.182-190
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    • 1993
  • In manufacturing process of semiconductor package, the thermal stress owing to high temperature in moulding and the bubbles generated in chip bonding process become main causes to produce void. On this study we evaluated quantitatively void size by use of ultrasonic spectroscopy method which analyze the reflective pulses with broad band frequency in frequency domain, and after destructive testing we verified effectiv- eness of sizing void by use of ultasonic spectroscopy.

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Analytical Study of Polarization Spectroscopy for the Jg=0 → Je=1 Transition

  • Noh, Heung-Ryoul
    • Journal of the Optical Society of Korea
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    • 제17권3호
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    • pp.279-282
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    • 2013
  • This work presents a theoretical study on the analytical calculation of the lineshape of polarization spectroscopy (PS) for the transition line $5s^2\;^1S_0{\rightarrow}5s5p\;^1P_1$ of $^{88}Sr$. From the obtained analytical form of the PS spectrum, we were able to identify how the saturation affected the lineshape of the PS spectrum. The results obtained will be useful for polarization spectroscopy experiments using the alkaline-earth atoms such as Sr or Yb.

Di-Urea 그리이스 증주제 합성과 구조분석에 관한 연구 (Thickener Syntheses and Structure Analysis of Di-Urea Grease)

  • 엄기청;정근우;조원오;김영운;서인옥;임수진;박교범
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1998년도 제28회 추계학술대회
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    • pp.306-312
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    • 1998
  • This paper describes syntheses of thickener for di-urea grease using constant velocity joint. The thickeners of di-urea grease were synthesized by reaction of diisocyanate with various alkylamines, hexylamine, octylamine, stearylamine and cyclohexylamine at high temperatxire. The synthesized thickener were analyzed by FT-IR spectroscopy and two kinds of Mass spectroscopy (EI & FAB). Dropping point and Consistency of synthesized di-urea grease were determined.

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Polarized Raman Spectroscopy of Graphene

  • Cheong, Hyeon-Sik
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.5-5
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    • 2011
  • Raman spectroscopy has become one of the most widely used tools in graphene research. The resonant Raman scattering process that gives rise to the observed strong Raman signal carries information regarding the electronic structure as well as the structural properties. When polarization of the incident excitation laser light or the scattered signal is carefully controlled, more information on the electronic and structural properties becomes available. In this tutorial, the basics of polarized Raman scattering experiments will be introduced first. Then several examples from real research will be highlighted to illustrate the application of polarized Raman spectroscopy in graphene research.

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Rapid Compositional Analysis of Naphtha by Near-Infrared Spectroscopy

  • 구민식;정호일;이준식
    • Bulletin of the Korean Chemical Society
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    • 제19권11호
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    • pp.1189-1193
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    • 1998
  • The determination of total paraffin, naphthene, and aromatic (PNA) contents in naphtha samples, which were directly obtained from actual refining process, has been studied using near-infrared (NIR) spectroscopy. Each of the total PNA concentrations in naphtha has been successfully analyzed using NIR spectroscopy. Partial least squares (PLS) regression method has been utilized to quantify the total PNA contents in naphtha from the NIR spectral bands. The NIR calibration results showed an excellent correlation with those of conventional gas chromatography (GC). Due to its rapidity and accuracy, NIR spectroscopy is appeared as a new analytical technique which can be substituted for the conventional GC method for the quantitative analysis of petrochemical products including naphtha.

해면 Luffariella sp.의 화학적 성분 연구 (A Study on the Chemical Constituents from Marine Sponge Luffariella sp.)

  • 박선구;김성수;박준대;홍정선;김인규
    • 대한화학회지
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    • 제39권7호
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    • pp.559-563
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    • 1995
  • 인도네시아 Manado만의 Sulawesi에서 채집한 KB cancer cell line에 대해 in vitro로 활성을 갖는 해면 Luffariella sp.으로부터 Germacrene alcohol(1), Aaptamine(2) 및 Hexacyclic terpene(3)을 분리하였으며, 1에대한 spectral data는 문헌치와 비교${\cdot}$분석하여 수정하였다. 이들을 $^1H$, $^13C$ NMR, $^1H$ $^13C$(bond) Heteronuclear Multiple Quantum Coherence Spectroscopy(HMQC), $^1H$$^13C$(2 and 3 bond)Heteronuclear Multiple Bond Correlation Spectroscopy(HMBC), Electron Impact Mass Spectroscopy(EI ms), UV 및 IR에 의해 밝혔다.

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