• Title/Summary/Keyword: Fourier Transform Spectroscopy

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Indium Modified Mesoporous Zeolite AlMCM-41 as a Heterogeneous Catalyst for the Knoevenagel Condensation Reaction

  • Katkar, Santosh S.;Lande, Machhindra K.;Arbad, Balasaheb R.;Rathod, Sandip B.
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1301-1304
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    • 2010
  • The Indium modified mesoporous zeolite AlMCM-41 were synthesized by hydrothermal method and characterized by powder X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) techniques. The Knoevenagel condensation of aldehyde with malononitrile or ethyl cyanoacetate was carried out at reflux condition in ethanol by using heterogeneous In/AlMCM-41 catalyst. This method is fast, efficient, easy work-up and eco-friendly to afford the corresponding Knoevenagel adducts. The catalyst was recovered and reused for several cycles with consistent activity.

A modified electrode by a facile green preparation of reduced graphene oxide utilizing olive leaves extract

  • Baioun, Abeer;Kellawi, Hassan;Falah, Ahamed
    • Carbon letters
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    • v.24
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    • pp.47-54
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    • 2017
  • Different phytochemicals obtained from various natural plant sources are used as reduction agents for preparing gold, copper, silver and platinum nanoparticles. In this work a green method of reducing graphene oxide (rGO) by an inexpensive, effective and scalable method using olive leaf aqueous extract as the reducing agent, was used to produce rGO. Both GO and rGO were prepared and investigated by ultraviolet and visible spectroscopy, Fourier-transform infrared, scanning electron microscopy, atomic force microscopy, thermogravimetric analysis, cyclic voltammetry, X-ray photoelectron spectra, electrochemical impedance spectroscopy and powder X-ray diffraction.

Changes of Surface Properties by Plasma Treatment on the Surface of Semiconductive Silicone Rubber (반도전성 실리콘 고무의 플라즈마 처리에 따른 표면의 특성변화)

  • Lee, Ki-Taek;Huh, Chang-Su
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.8
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    • pp.696-701
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    • 2005
  • This paper was investigated the changes of surface properties of high-temperature-vulcanized (HTV) semiconductive silicone rubber due to oxygen plasma discharge. The modifications produced on the silicone rubber surface by oxygen plasma were accessed using Fourier transform infrared spectroscopy(FTIR), X-ray photoelectron spectroscopy(XPS), contact angle and Surface Roughness Tester. The results of the chemical analysis Showed that C-H bonds were broken due to plasma discharge and Silica-like bonds (SiOx, x=$3\~4$) increased. It is thought that the above changes lead to the increase of surface energy of high-temperature-vulcanized (HTV) semiconductive silicone rubber also, Surface roughness was increased with cleavage of side-chains and oxidation process, it confirmed change as the SEM. The micromorphology of surface and hydrophobicity due to plasma discharge based on our results were discussed.

Study of Carbon Nanotubes Properties by Post-treatment Conditions (후처리 조건에 따른 탄소나노튜브 특성의 변화)

  • Choi Sung-Hun;Lee Jae-Hyeong;Yang Jong-Seok;Park Dae-Hee;Heo Jeong-Ku
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.10
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    • pp.930-934
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    • 2006
  • This paper reports a change of carbon nanotubes(CNTs) properties by post-treatment process after growth of CNTs. CNTs were treated by thermal method and solution method, and then investigated in detail using field emission scanning electron microscopy(FE-SEM), high resolution transmission scanning electron microscopy(HR-TEM), RAMAN spectroscopy, and Fourier Transform Infrared Spectrometer (FT-IR). FT-IR spectra showed that the amount of hydroxyl generated on surface of CNTs were changed with post-treatment condition. FE-SEM and TEM images were shown CNTs diameter and density variations were dependent with their treatment conditions. RAMAN spectroscopy was shown that carbon nanotubes structure vary with treatment conditions.

Effects of electrochemical oxidation of carbon fibers on interfacial shear strength using a micro-bond method

  • Kim, Dong-Kyu;An, Kay-Hyeok;Bang, Yun Hyuk;Kwac, Lee-Ku;Oh, Sang-Yub;Kim, Byung-Joo
    • Carbon letters
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    • v.19
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    • pp.32-39
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    • 2016
  • In this work, we studied the effects of electrochemical oxidation treatments of carbon fibers (CFs) on interfacial adhesion between CF and epoxy resin with various current densities. The surface morphologies and properties of the CFs before and after electrochemical-oxidation-treatment were characterized using field emission scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and single-fiber contact angle. The mechanical interfacial shear strength of the CFs/epoxy matrix composites was investigated by using a micro-bond method. From the results, electrochemical oxidation treatment introduced oxygen functional groups and increased roughness on the fiber surface. The mechanical interfacial adhesion strength also showed higher values than that of an untreated CF-reinforced composite.

Optical properties of amorphous $Si_xC_yN_z$ ternary thin films prepared by plasma enhanced chemical vapor deposition

  • Zhang, Z.H.;Fan, X.J.;Guo, H.X.;Zhang, W.;Zhang, C.Y.;Luo, F.Y.
    • Journal of the Korean Vacuum Society
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    • v.7 no.s1
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    • pp.190-196
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    • 1998
  • Amorphous ternary $Si_xC_yN-z$ thin films were obtained by plasma enhanced chemical vapor deposition(PECVD) using $N_2, SiH_4 \;and \;C_2H_4$ as the reaction sources. The chemical state were characterized by x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy(FTIR). The optical properties of the thin films were investigated by UV-visible spectrophotometer and ellipsometer, and the optical band gaps of thin films were determined from corresponding transmittance spectra following Tauc equation.

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Durable Press Finishing of Silk/Cotton Fabrics with BTCA (3) - The Study of Ester Crosslinkages of Silk/Cotton Fabrics Treated with BTCA by FT-IR Spectroscopy - (BTCA에 의한 실크/면 교직물의 DP 가공 (3) - FT-IR 분광법에 의한 BTCA 처리 실크/면 교직물의 에스테르 가교 평가 -)

  • Cho, Seok-Hyun;Kim, Yong;Park, Jong-Jun;Lee, Moon-Chul
    • Textile Coloration and Finishing
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    • v.15 no.4
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    • pp.17-23
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    • 2003
  • Fourier transform infrared spectroscopy(FT-IR) was used to characterize the intermolecular ester crosslinkages in cotton cellulose. The FT-IR data show that the band of the ester carbonyl group can be separated from overlapping carboxyl/carbonyl band by converting carboxyl group to carboxylate. When esterification occurs between a polycarboxylic acid and cotton cellulose, the carbonyl groups retained in the cotton exist in three forms; ester, carboxyl, and carboxylate anion. The FT-IR data were also correlated to the durable press rating result obtained. The appearance of BTCA-finished durable press silk/cotton fabrics were improved.

Modification of Polymer Surface by Corona Discharge and the Subsequent Graft Polymerization of Acrylamide (코로나 방전처리와 아크릴아미드 그라프트 중합에 의한 고분자 표면개질)

  • 김형우;김찬영;박병기
    • Textile Coloration and Finishing
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    • v.5 no.1
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    • pp.26-32
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    • 1993
  • This study is concerned with the graft polymerization of acrylamide onto the surfaces of polyethylene and polyethylene terephthalate films treated with on corona discharge. In the case, peroxides formed by the corona discharge treatment are likely to be the species responsible for initiating the graft polymerization. This treatment produced a continuous charge in wettability and also amid group density on the polymer surface, as evidenced by water contact angle measurement, Fourier-transform infrared spectroscopy in the attenuated total reflectance mode, and electron spectroscopy for chemical analysis. Both of the merely corona-treated film and the subsequently grafted film are discussed as a function of time after treatment and water washings.

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Preparation and Characterization of Ultramicroporous Carbons for Hydrogen Storage (초미세기공을 지니는 탄소분자체의 수소저장거동)

  • Lee, Seul-Yi;Park, Soo-Jin
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.158.1-158.1
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    • 2011
  • In this work, we prepared ultramicroporous carbons (UC) prepared by pyrolyzing poly(vinylidene fluoride) with different carbonization temperatures, and investigated the hydrogen storage behaviors. The surface functional groups and specific elements of UC were confirmed by Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), respectively. Textural properties were analyzed using $N_2$ adsorption isotherms at 77 K. The hydrogen storage capacity of the UC samples were investigated by BEL-HP at 298 K/10 MPa. From the results, it was found that the hydrogen storage capacity was enhanced with increasing of specific surface area, resulting from the formation of ultramicropore on the UC.

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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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