• Title/Summary/Keyword: IR spectroscopy

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Characterization of Selectively Absorbing Properties of Indium Tin Oxide Thin Films by UV-VIS-IR Spectroscopy (UV-VIS-IR 분광법에 의한 산화 인듐 주석 박막의 선택적 투과 흡수 특성 관찰)

  • Lee, Jeon-Kook;Lee, Dong-Heon;Cho, Nam-Hee
    • Analytical Science and Technology
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    • v.5 no.1
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    • pp.135-142
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    • 1992
  • Indium tin oxide(ITO) films coated on the window glass selectively transmit the solar energy and infrared. We call this system passive solar collectors. Selectively absorbing properties of sol gel dip coated ITO films were characterized by UV-VIS-NIR spectroscopy. The effects of heat treating temperature, time, atmosphere, substrate and barrier layers are concerned. Indium tin oxide films heat-treated at $500^{\circ}C$ in a reducing atmosphere show intrinsic properties. Efficiency of solar energy transmittance was enhanced by coating of $SiO_2-ZrO_2$ as an alkali ion barrier layer. Energy was saved by the double layers of $SiO_2-ZrO_2$ and ITO since solar energy is transmitted and heat generated inside(${\lambda}$ > 2700nm) is reflected.

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Generalized Two-dimensional (2D) Correlation Spectroscopy: Principle and Its Applications (일반화된 이차원 상관 분광학: 원리 및 응용)

  • Young Mee Jung;Seung Bin Kim
    • Journal of the Korean Chemical Society
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    • v.47 no.5
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    • pp.447-459
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    • 2003
  • Generalized 2D correlation spectroscopy has been applied extensively to the analysis of spectral data sets obtained during the observation of a system under some external perturbation. It is used in various fields of spectroscopy including IR, Raman, UV, fluorescence, X-ray diffraction, and X-ray absorption spectroscopy (XAS) as well as chromatography. 2D hetero-spectral correlation analysis compares two completely different types of spectra obtained for a system under the same perturbation. Because of the wide range of applications of this technique, it has become one of the standard analytical techniques for the analytical chemistry, physical chemistry, biochemistry, and so on, and for studies of polymers, biomolecules, nanomaterials, etc. In this paper, we will introduce the principle of generalized 2D correlation spectroscopy and its applications that we have studied.

Polyaniline/SiO2 Catalyzed One-pot Mannich Reaction: An Efficient Synthesis of β-amino Carbonyl Compounds (Polyaniline/SiO2를 이용한 one-pot Mannich 반응: β-amino carbonyl 화합물의 효율적인 합성)

  • Yelwande, Ajeet A.;Arbad, Balasaheb R.;Lande, Machhindra K.
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.644-649
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    • 2011
  • Polyaniline/$SiO_2$ catalyzed one-pot mannich reaction of acetophenone, aromatic aldehydes and aromatic amines are carried out in ethanol to afford various ${\beta}$-amino ketones. The various wt% of polyaniline were supported on pure silica synthesized by using chemical oxidative method. The catalyst prepared has been characterized by means of thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR). Solvent stability of catalyst was tested using UV-Visible spectroscopy. This protocol has several advantages such as high yield, simple work up procedure, non-toxic, clean, easy recovery and reusability of the catalyst.

IR Absorption Property in Nano-thick Nickel Silicides (나노급 두께 니켈실리사이드의 적외선 흡수 특성)

  • Yoon, Ki-Jeong;Han, Jeung-Jo;Song, Oh-Sung
    • Korean Journal of Materials Research
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    • v.17 no.6
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    • pp.323-330
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    • 2007
  • We fabricated thermaly evaporated 10 nmNi/(poly)Si films to investigate the energy saving property of silicides formed by rapid thermal annealing (RTA) at the temperature of $300{\sim}1200^{\circ}C$ for 40 seconds. Moreover, we fabricated $10{\sim}50$ nm-thick ITO/Si films with a rf-sputter as reference films. A four-point tester was used to investigate the sheet resistance. A transmission electron microscope (TEM) and an X-ray diffractometer were used for the determination of cross sectional microstructure and phase changes. A UV-VISNIR and FT-IR (Fourier transform infrared rays spectroscopy) were employed for near-IR and middle-IR absorbance. Through TEM analysis, we confirmed $20{\sim}70nm-thick$ silicide layers formed on the single and polycrystalline silicon substrates. Nickel silicides and ITO films on the single silicon substrates showed almost similar absorbance in near-IR region, while nickel silicides on polycrystalline silicon substrate showed superior absorbance above 850 nm near-IR region to ITO films. Nickel silicide on polycrystalline substrate also showed better absorbance in middle IR region than ITO. Our result implies that nano-thick nickel silicides may have exellent absorbing capacity in near-IR and middle-IR region.

Syntheses and Reactions of Iridium Complexes Containing Mixed Phosphine-Olefin Ligand: (3-(Diphenylphosphino)propyl)(3-butenyl)phenylphosphine

  • Young-ae W. Park;Devon W. Meek
    • Bulletin of the Korean Chemical Society
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    • v.16 no.6
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    • pp.524-528
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    • 1995
  • The reaction of [IrCl(cod)]2 with ppol ligand, Ph2PCH2CH2CH2P(Ph)CH2CH2CH=CH2, in ethanol gives an iridium complex, whose structure is converted from an ionic form, [Ir(cod)(ppol)]Cl·2C2H5OH (1),in polar solvents (ethanol, methanol and acetonitrile), to a molecular form, [IrCl(cod)(ppol)], in non-polar solvents (benzene and toluene). The cationic complexes, [Ir(cod)(ppol)]AsF6·1/2C2H5OH and [Ir(cod)(ppol)]PF6·1/2CH3CN, were prepared to compare with the ionic form by 31P NMR spectroscopy. When carbon monoxide is introduced to 1, cod is replaced by CO to give the 5-coordinated complex, [IrCl(CO)(ppol)]. Hydrogenation of 1-octene was not successful in the presence of 1. In order to verify the reason for 1 not behaving as a good catalyst for hydrogenation, electrophilic reactions with HCl, I2 and HBF4·etherate were performed, which yielded the oxidative addition product, [IrHCl2(ppol)], the substitution product, [IrI(cod)(ppol)], and another cationic product, [Ir(cod)(ppol)]BF4, respectively. Thus, the iridium complex is not sufficiently basic to activate hydrogen atoms or the olefin of the ppol ligand.

Infrared Scanning Near-Field Optical Microscopy (IR-SNOM) Below the Diffraction Limit

  • Sanghera, J.S.;Aggarwal, I.D.;Cricenti, A.;Generossi, R.;Luce, M.;Perfetti, P.;Margoritondo, G.;Tolk, N.;Piston, D.
    • Ceramist
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    • v.10 no.3
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    • pp.55-66
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    • 2007
  • Infrared Scanning Near-field Optical Microscopy (IR-SNOM) is an extremely powerful analytical instrument since it combines IR spectroscopy's high chemical specificity with SNOM's high spatial resolution. In order to do this in the infrared, specialty chalcogenide glass fibers were fabricated and their ends tapered to generate SNOM probes. The fiber tips were installed in a modified near field microscope and both inorganic and biological samples illuminated with the tunable output from a free-electron laser located at Vanderbilt University. Both topographical and IR spectral images were simultaneously recorded with a resolution of ${\sim}50\;nm$ and ${\sim}100\;nm$, respectively. Unique spectroscopic features were identified in all samples, with spectral images exhibiting resolutions of up to ${\lambda}/60$, or at least 30 times better than the diffraction limited lens-based microscopes. We believe that IR-SNOM can provide a very powerful insight into some of the most important bio-medical research topics.

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Genetic Discrimination of Catharanthus roseus Cultivars by Multivariate Analysis of Fourier Transform Infrared Spectroscopy Data

  • Kim, Suk-Weon;Cho, Soo-Hwa;Chung, Hoe-Il;Liu, Jang-R.
    • Journal of Plant Biotechnology
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    • v.34 no.3
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    • pp.201-205
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    • 2007
  • To determine whether pattern recognition based on metabolite fingerprinting for whole cell extracts of higher plants is applied to discriminate plants genetically, leaf samples of eight cultivars of Catharanthus roseus were subjected to Fourier transform infrared spectroscopy (FT-IR). FT-IR fingerprint region data were analyzed by principal component analysis (PCA). Major peaks as biomarkers were identified as the most significant contributors to distinguish samples by using genetic programming. A hierarchical dendrogram based on the results from PCA separated the eight cultivars into two major groups in the same manner as the dendrograms based on genetic fingerprinting methods such as RAPD and AFLP. A slight difference between the dendrograms was found only in branching pattern within each subgroup. Therefore, we conclude that the hierarchical dendrogram based on PCA of the FT-IR data represents the most probable chemotaxonomical relationship between cultivars, which is in general agreement with the genetic relationship determined by conventional DNA fingerprinting methods.

Effects of Polycarboxylate Type Superplasticizer on the Hydration of Ordinary Portland Cement (보통포틀랜드시멘트의 수화 반응에 미치는 폴리카복실레이트계 고유동화제의 영향)

  • 류호석;송종택
    • Journal of the Korean Ceramic Society
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    • v.41 no.5
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    • pp.417-424
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    • 2004
  • Polycarboxylate type superplasticizers (PCA) with different graft chain (Polyethylene oxide) length were synthesized by Methoxypoly (ethyleneglycol)monomethacrylate (MPEGMAA) and methacrylic acid (MAA). The effects of PCA on the hydration of Ordinary Portland Cement (OPC) were investigated by Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques. The effect of graft chain length of PCA on the hydration of OPC was different at early age, but, at long age, was similar. The ratio of relative peak intensity, (I[001]/I[101]), of Ca(OH)$_2$ compared with OPC also was reduced by PCA addition.

Kinetics of Acrylamide Solution Polymerization Using Potassium Persulfate as an Initiator by in situ IR

  • Kang, Shin-Choon;Park, Yoo-Jeong;Kim, Hyung-Zip;Kyong, Jin-Burm;Kim, Dong-Kook
    • Macromolecular Research
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    • v.12 no.1
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    • pp.107-111
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    • 2004
  • We have studied the polymerization kinetics of acrylamide in aqueous solution with potassium persulfate as an initiator by using quantitative real-time in situ IR spectroscopy and monitoring the profiles of peaks in the range 1900-850 cm$\^$-1/. The conversion of acrylamide was calculated from the disappearance of the peak at 988 cm$\^$-1/, which is the out-of-plane bending mode of the=C-H unit, normalized to the C=O stretching peak at 1675 cm$\^$-1/, as an internal standard. For reaction temperatures in the range 40-65$^{\circ}C$ and initiator and monomer concentrations of 0.9-2.6 mmol/L and 0.5-1.1 mol/L, respectively, we deduced that the rate of monomer consumption follows the relation R$\_$p/=k[K$_2$S$_2$O$\_$8/]$\^$0.5/ [Μ]$\^$1.35${\pm}$0.10/. In addition, we obtained activation parameters from an evaluation of the kinetic data.

The Study on Characteristics of N-Doped Ethylcyclohexane Plasma-Polymer Thin Films

  • Seo, Hyeon-Jin;Jo, Sang-Jin;Lee, Jin-U;Jeon, So-Hyeon;Bu, Jin-Hyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.540-540
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    • 2013
  • In this studying, we investigated the basic properties of N-doped plasma polymer. The N-doped ethylcyclohexane plasma polymer thin films were deposited by radio frequency (13.56 MHz) plasma-enhanced chemical vapor deposition method. Ethylcyclohexenewas used as organic precursor (carbon source) with hydrogen gas as the precursor bubbler gas. Additionally, ammonia gas [NH3] was used as nitrogen dopant. The as-grown polymerized thin films were analyzed using ellipsometry, Fourier-transform infrared [FT-IR] spectroscopy, Raman spectroscopy, FE-SEM, and water contact angle measurement. The ellipsometry results showed the refractive index change of the N-doped ethylcyclohexene plasma polymer film. The FT-IR spectrashowed that the N-doped ethylcyclohexene plasma polymer films were completely fragmented and polymerized from ethylcyclohexane.

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