• Title/Summary/Keyword: elemental analysis

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Synthesis and Optical Properties of Poly[6'-(N-carbazolyl)hexyl-2-ethynylpyridinium bromide]

  • 갈영순;이상섭;배장순;김봉식;장상희;진성호
    • Bulletin of the Korean Chemical Society
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    • v.20 no.4
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    • pp.451-455
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    • 1999
  • The polymerization of 2-ethynylpyridine by alkyl bromide carrying carbazole moiety, 6-(N-carbazolyl)hexyl bromide, relatively proceed well to give the corresponding poly[6'-(N-carbazolyl)hexyl-2-ethynylpyridinium bromide) in high yields under DMF reflux conditions without any initiator or catalyst. This polymerization was influenced upon the initial monomer concentration. The polymer yields and inherent viscosities of the resulting polymers were in the range of 34-85% and 0.11-0.21 dL/g, respectively. Instrumental analyses using NMR, IR, and UV-visible spectroscopies and elemental analysis indicated that the resulting polymer has a conjugated polymer backbone system carrying pyridine and n-hexyl carbazole moiety. The polymers were mostly brown powders and completely soluble in DMF, DMSO, nitrobenzene, and formic acid. The photoluminescence spectrum of the dilute polymer solution with the excitation at 383 nm exhibited two sharp peaks at 495 and 540 nm.

Synthesis and Characterization of Molybdenum(V) Complexes with Tridentate Schiff Bases

  • Jung Sook Kim;Bon Kweon Koo
    • Bulletin of the Korean Chemical Society
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    • v.13 no.5
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    • pp.507-511
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    • 1992
  • Six-coordinate molybdenum(V) complexes X[MoO$(NCS)_2$(L)], where X=$PyH^+$, $Me_4N^+$, $Et_4N^+$, n-$Bu_4N^+$, and L= the tridentate schiff base dianions derived from the condensation reaction between various salicylaldehydes and 2-aminophenol have been synthesized. The complexes have been characterized by elemental analysis, conductivity, UV-visible, IR, $^1H$-NMR, and mass spectroscopy. The coordination around the molybdenum appears to be distorted octahedral. A tridentate ligand containing the ONO donor atoms occupies meridional positions with the N atom trans to the terminal oxo group. Two NCS ligands bond to the molybdenum through the N atom and are cis to the Mo = $O_t$ group. The electrochemical behaviors of the complexes have also been investigated by cyclic voltammetry in dimethylsulfoxide.

Syntheses and Theoretical Study of Palladium(II) Complexes with Aminophosphines as 7-Membered Chelate Rings

  • 김봉곤;양기열;정맹준;이배욱;도명기
    • Bulletin of the Korean Chemical Society
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    • v.18 no.11
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    • pp.1162-1166
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    • 1997
  • Nature of palladium(Ⅱ) complexes with 7-membered chelates was studied by experimental and theoretical methods on a Pd(L)Cl2 system, where L is Ph2PNHCH2CH2NHPPh2(L1), Ph2PNHC6H4NHPPh2(L2). The palladium(Ⅱ) complexes were prepared and characterized by elemental analysis, IR, UV, 1H, and 31P NMR spectroscopy. Ab initio calculations with geometry optimizations were also performed for related model systems, Pd(L)Cl2; L=R2PNH(CH2)2NHPR2(L3), R2PNHC6H4NHPR2(L4), R2P(CH2)4PR2(L5), R2PCH2(C6H4)CH2PR2(L6); R=H, CH3.

Analysis of Optical Characteristics of Transparent Glasses for PV and Glass-Glass Module Application (PV용 투명유리와 G/G모듈의 광학적 특성 평가 및 분석)

  • Kim, Kyung-Soo;Kang, Gi-Hwan;Yu, Gwon-Jong
    • Journal of the Korean Solar Energy Society
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    • v.28 no.5
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    • pp.8-13
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    • 2008
  • In this study, we analyze the electrical optical characteristics of transparent glass for photovoltaic and glass-glass module application. The elemental facts from raw glass to laminated glass with solar cells are analyzed using UV spectrophotometer and spectroradiometer. From the data of transmittance and reflectance, the optimum PV module processing condition and selection of material for fabrication should be considered deeply for obtaining high module efficiency. Also we introduce two glasses which has 2%$\sim$4% higher transmittance using coating technology with anti-reflection material. From this experiment, we try to give some basic information for PV module manufacturing industry. The detail description is specified as the following paper.

Synthesis and Optical Characterization of 2,5-Dibromo-3,4,6,7,8,9-hexaphenyl-1-silaspiropenta-2,4,6,8-tetraene (2,5-Dibromo-3,4,6,7,8,9-hexaphenyl-1-silaspiropenta-2,4,6,8-tetraene의 합성 및 광학적 특성 조사)

  • Park, Jaehyun
    • Journal of Integrative Natural Science
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    • v.2 no.4
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    • pp.270-274
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    • 2009
  • Organometallic polymers containing spirosilole unit have been interested, since spirosiloles has a unique optical and electronic properties. New functionalized spirosiloles (2,5-dibromo-3,4,6,7,8,9-hexaphenylspirosilole, DBHPSS) have been synthesized from the reduction of bis(1,1-phenylethynyl)-2,3,4,5-tetraphenylsilole with lithium naphthalenide for the possible applications in optics. DBHPSS has been characterized by $^1H$-NMR, fluorescence, and UV-vis absorption spectroscopy and elemental analysis. Bis(phenylethynyl)tetraphenylsilole displays an emission maxima at 490 nm with an excitation wavelength of 380 nm. However, DBHPSS displays an emission maxima at 550 nm with an excitation wavelength of 420 nm.

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Polyacetylene Compounds from Panax Ginseng C. A. Meyer

  • Shim, Sang-Chul;Koh, Hun-Yeoung;Han, Byung-Hoon
    • Bulletin of the Korean Chemical Society
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    • v.4 no.4
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    • pp.183-188
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    • 1983
  • Two major and two minor polyacetylenes were isolated from fresh white Korean ginseng roots. The petroleum ether-ethyl ether fractions containing the polyacetylene compounds were collected through solvent fractionation, partition and silica gel column chromatography. Further separation of polyacetylenic fractions was proceeded by bonded normal phase HPLC utilizing a moderately nonpolar microparticulate column. The low pressure liquid chromatography was used for the semi-preparative separation. The chemical structures of the two major polyacetylenes separated were determined by UV, IR, $^1H$ NMR, $^{13}C$ NMR, mass spectra and elemental analysis. One of them is identified to be heptadeca-1-en-4, 6-diyne-3, 9, 10-triol, a new structure, and the other is heptadeca-1, 9-dien-4, 6-diyn-3-ol, known as panaxynol.

Alanine and S-Methylcysteine Cobalt (III) Complexes of Ethylenediamine-N,N'-di-${\alpha}$-butyric Acid

  • Moo-Jin Jin;Jio Woo Cheon;Sung Rack Choi
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.251-253
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    • 1990
  • L-Alanine(L-ala) and S-methyl-L-cysteine(L-mcy) cobalt(III) complexes of a flexible $N_2O_2$-type tetradentate ligand ethylenediamine-N,N'-di- -butyric acid(eddb), s-cis-[Co(eddb)(L-ala)] and s-cis-[Co(eddb)(L-mcy), have been prepared via the substitution reactions of the s-cis-$[Co(eddb)Cl_2]$-complex with, respectively, L-alanine and S-methyl-L-cysteine. Both L-alanine and S-methyl-L-cysteine are found to coordinate to the cobalt(III) ion via the nitrogen and oxygen donor atoms to give the meridional s-cis isomer. Electronic absorption, ir and pmr spectra are used to characterize the complexes obtained in this work along with elemental analysis data.

Synthesis and Catalytic Properties of Ruthenium(Ⅲ) Unsymmetrical Schiff Base Complexes

  • Yeo Hwhan-Jin;Lim Jong-Wan
    • Bulletin of the Korean Chemical Society
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    • v.13 no.3
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    • pp.265-268
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    • 1992
  • Ruthenium(III) unsymmetrical Schiff base complexes, $[Ru(CHBPH-TP)Cl_2]$ and $K[Ru(CHBPH-HB)Cl_2]$ were synthesized, where CHBPH-TP and CHBPH-HB are 5-chloro-2-hydroxybenzophenonethiophencarba aldehydephenylenediimine and 5-chloro-2-hydroxybenzophenonehydroxybenzophe nonephenylenediimine. These Schiff bases were obtained from the reactions of 5-chloro-2-hydroxybenzophenone (CHB) and 2-thiophenecarbaldehyde (TP) or hyroxybenzophenone (HB) and 1,2-diaminobenzene. Elemental analysis, conductivity and infrared studies of the complexes suggest an octahedral geometry around ruthenium. Magnetic moments of the complexes indicate a single unpaired electron in alow spin $d^5$ configuration. The complexes are capable of catalyzing the oxidation of styrene with sodium hypochlorite in the presence of phase transfer agent. Oxidative cleavage of C=C bond is the major reaction pathway to form benzaldehyde for styrene oxidation.

New Polyacetylene Compounds from Panax Ginseng C. A. Meyer$^\dag$

  • Shim, Sang-Chul;Chang, Suk-Ku;Hur, Chan-Woo;Kim, Chang-Kew
    • Bulletin of the Korean Chemical Society
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    • v.8 no.4
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    • pp.272-275
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    • 1987
  • Two polyacetylene compounds having diyn-ene chromophore were isolated from fresh Korean ginseng roots through solvent fractionation, partition and silica gel column chromatography. The low pressure semi-preparative liquid chromatography and high performance preparative liquid chromatography were used for final separation of polyacetylenic fractions. The chemical structures of these polyacetylenes were determined to be heptadeca-1,8-dien-4,6-diyn-3,10-diol and heptadeca-1,4-dien-6,8-diyn-3,10-diol by UV, FT-IR, $^1H\;NMR,\;^{13}C\;NMR,$ mass spectra and elemental analysis.

Preparation and Thermal Properties of Enaminonitriles-Terminated Reactive Polymer Precursors

  • 박원순;길덕수;공명선
    • Bulletin of the Korean Chemical Society
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    • v.19 no.3
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    • pp.291-295
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    • 1998
  • Various enaminonitriles-terminated reactive polymer precursors containing rigid aromatic and flexible alkyl units were prepared from the corresponding diamines and 1-chloro-1-phenyl-2,2-dicyanoethene (1). All the enaminonitriles-terminated precursors were characterized by spectroscopies and elemental analysis. They were highly soluble in DMF and NMP, and partially soluble in common organic solvents such as THF and acetone. They showed a large exotherm around 350 ℃ attributable to the thermal polymerization by crosslinking of the dicyanovinyl group. Upon heating the precursors, heat-resistant and insoluble network polymers were obtained. Thermogravimetric analyses of the precursors containing rigid aromatic moiety exhibited thermal stability with a 10% weight loss around 420-480 ℃ and 75-88% residual weight at 500 ℃ under nitrogen.