• Title/Summary/Keyword: absorption spectra

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Solvent Effects on the Electronic Spectra of Some Heterocyclic Azo Dyes

  • Behera, Pradipta Kumar;Xess, Anita;Sahu, Sachita
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.610-616
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    • 2014
  • The influence of solvent polarity on the absorption spectra of some synthesized azo dye with heterocyclic moieties and ${\beta}$-naphthol (1-3) have been investigated using a UV-Visible spectrophotometer. The spectral characteristics of the azo dyes (1-3) in different solvents at room temperature were analyzed. The solvatochromic empirical variables like ${\pi}^*$, ${\alpha}$, and ${\beta}$ have been used to discuss the solvatochromic behaviour of the dyes and to evaluate their contributions to the solute-solvent interactions. A multi-parameter regression model for quantitative assessment of the solute/solvent interaction and the absorption has been used to explain the solvent effect on azo dyes (1-3).

Immunological Relationship Based on Phycerythrin in Campylaephora crassa, Rhodophyta and Its Related Species (홍조식물 굵은석묵(Campylaephora crassa)과 근연종의 Phycoerythrin에 의한 면역학적 유연관계)

  • 박형신
    • Journal of Plant Biology
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    • v.36 no.1
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    • pp.91-96
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    • 1993
  • Phycoerythrins from the ceramiaceous red algae Campylaephora crassa (Okamura) Nakamura and related species, C. hypnaeoides J. Agardh and Ceramium kondoi Yendo, were investigated for absorption spectra, protein bands by gel electrophoresis and antigenic reactivity to anti-phycoerythrin using Ouchterlony double diffusion and immunoblot. Similarities in absorption spectra, showing peaks at ca. 566 nm>534 nm>495 nm, were found between C. crassa and Cm. kondoi, while C. hypnaeoides differed slightly. There were no differences in fluorescence emission spectra and protein bands between C. crassa and related species tested. Since Ouchterlony double diffusion, however, showed that phycoerythrins from C. crassa and Cm. kondoi were similar in antigenic reactions, and differed from that of C. hypnaeoides, the taxonomic position of C. crassa should be reinvestigated using other experimental approaches.

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Analysis of Drugs and Chemicals by Infrared Absorption Spectrophotometry(II) Quantitative Analysis of Sulfamethoxydiazine and Sulfamethoxypyridazine in Pharmaceutical Preparations. (Infrared spectrophotometry에 의한 의약품의 분석연구 (II) 적외선흡수 Spectra에 의한 Sulfamethoxydiazine 및 Sulfamethoxy-pyridazine의 정량분석)

  • 옥치완;권영훈
    • YAKHAK HOEJI
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    • v.13 no.2_3
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    • pp.51-56
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    • 1969
  • In quantitative analysis of sulfonamide drugs by means of infrared Spectrophotometry, the author tried to analyse Sulfamethoxydiazine and Sulfamethoxypyridazine in their Pharmaceutical Preparations. By the survey of infrared absorption spectra of Sulfamethoxydiazine and Sulfamethoxypyridazine. We found quantitative properties at the peaks of wave number 1150 cm$^{-1}$ (Sulfamethoxydiazine) and 1090 cm$^{-1}$ (Sulfamethoxypyridazine) in the spectra. These peaks obey Beer's Law in a range of 50-150 ug for Sulfamethoxydiazine and 70-350 ${\mu}$g for Sulfamethoxypyridazine in 300 mg KBr disc. By this method, Sulfamethoxydiazine and Sulfamethoxypyridazine could be analyzed less than 2% error.

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Solvent Dependence of Absorption and Fluorescence Spectra of Piroxicam. A Possible Intramolecular Proton Transfer in the Excited State

  • Yoon, Min-Joong;Choi, Hyong-Nae;Kwon, Hwang-Won;Park, Koon-Ha
    • Bulletin of the Korean Chemical Society
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    • v.9 no.3
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    • pp.171-175
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    • 1988
  • The spectral properties of piroxicam in different solvents are similar to those of its skeletal precursor, HMBDC. The maximum absorption and emission wavelengths strongly depend on the hydrogen bonding ability of the solvent, and it is shown that intramolecular hydrogen bonding between the -OH and the ortho carbonyl group of the parent benzothiazine ring plays an important role in the solvent-dependence of their spectroscopic properties. The fluorescence spectra in aprotic nonpolar solvent exhibit abnormally large Stokes-shifted (${\sim}9,000cm^{-1}$) emission bands in contrast to the spectra in water. In ethanol, dual emission bands with two different fractional components of lifetimes have been observed. These results suggest that the abnormally red-shifted emission is attributed to the proton transferred form of an intramolecularly hydrogen-bonded closed conformer.

Optical Properties of (V, Pr)-doped ZrSiO4 Green Pigments (바나듐과 프라세오디뮴을 사용한 지르콘녹색안료의 광학적 특성)

  • Pyon, Kyu-Ri;Lee, Byung-Ha
    • Journal of the Korean Ceramic Society
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    • v.47 no.3
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    • pp.249-255
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    • 2010
  • To investigate optical properties of (V, Pr)-doped $ZrSiO_4$ green pigments, samples were prepared by the ceramic method using NaF and NaCl as mineralizers. They were characterized by X-ray diffraction, UV-Vis spectroscopy and Raman spectroscopy. The changes of color in the samples during heating and effect of mineralizers were studied in terms of valence of the vanadium and praseodymium in the zircon matrix. (V, Pr)-doped $ZrSiO_4$ pigments give rise to green coloration in $800^{\circ}C$. The oxidation state of V and Pr ions of pigments in the glazed samples were confirmed by UV-Vis absorption spectra. This absorption spectra showed three typical bands of trivalent Pr at the 445, 480~490, 592 nm due to f-f transitions and two broad bands of 302~380, 400~500 nm due to f-d transitions of tetravalent Pr. According to the increasing amounts of $Pr_6O_{11}$, the two broad bands showed decreasing intensity at 290, 640 nm due to d-d transitions of tetravalent V.

Fluorescence Analysis of Harmful Food Colors -Establishment of Fluorescence Assay Method by the Use of Filter Paper Adsorption- (유해성(有害性) 식품착색료(食品着色料)의 형광검사(螢光檢査) -여지흡착(濾紙吸着)을 이용한 형광분석법(螢光分析法)의 확립-)

  • Lee, Mie-Soon
    • Korean Journal of Food Science and Technology
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    • v.13 no.2
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    • pp.114-120
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    • 1981
  • A rapid and simple method for detecting colors was attempted on the basis of absorption and emission spectra of reflected light at $45^{\circ}$ angle from color-adsorbed filter paper illuminated by ultraviolet light through interference filter. Absorption spectra of prepared samples revealed more characteristic patterns than emission spectra. Detection of colors was readily accomplished by the investigation of wave length range, distribution pattern, the number of absorption bands and the degree of quenching.

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Synthesis, Crystal Structure and Density Functional Calculations on 1-Phenyl-3-p-fluorophenyl-5-p-chlorophenyl-2-pyrazoline

  • Zhao, Pu Su;Li, Yu Feng;Guo, Huan Mei;Jian, Fang Fang;Wang, Xian
    • Bulletin of the Korean Chemical Society
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    • v.28 no.9
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    • pp.1539-1544
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    • 2007
  • 1-Phenyl-3-p-fluorophenyl-5-p-chlorophenyl-2-pyrazoline has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray single crystal diffraction. Density functional calculations show that B3LYP/6-311G** method can reproduce the structural parameters. The electronic absorption spectra have been predicted based on the optimized structure by using 6-311G** and 6-311++G** basis sets and compared with the experimental values. The results indicate that TD-DFT method can only predict the electronic absorption spectra of the system studied here approximately. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between ,C0p,m,S0m,H0m and temperature.

Absorption and Fluorescence of Sm(III) Complexes with some Terdentate Ligands

  • Kim, Jong-Goo;Yoon, Soo-Kyung;Yun, Sock-Sung;Kang, Jun-Gill
    • Bulletin of the Korean Chemical Society
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    • v.13 no.1
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    • pp.54-59
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    • 1992
  • Spectroscopic measurements and theoretical calculations are performed for the four 1 : 3 Sm(III) : ligand solutions. The ligands included in this study are oxidiacetate, iminodiacetate, methyliminodiacetate and dipicolinate. The oscillator strengths for the $4f{\to}4f$ multiplet-to-multiplet transitions are empirically determined from the absorption spectra. The intensity parameters ${\Omega}_{\lambda}\;({\lambda}=2,\;4,\;6)$ of $Sm^{3+}$(aquo) and ${SmL_3}^{3-}$ complexes are also evaluated by applying the Judd-Ofelt theorem to the observed oscillator strengths. The values of the intensity parameters are compared and discussed in term of structural properties of the complexes. In addition, the fluorescence spectra are reported for the Sm(III) complex systems under mild alkaline condition. The excitation from the $^6H_{5/2}$ ground state to any excited states lying above the emitting energy level $(^4G_{5/2})$ produces four fluorescence bands, following nonradiative transitions from a certain excited state to the $^4G_{5/2}$ state. The ratios of oscillator strengths of ${SmL_3}^{3-}$ complexes to that of $Sm^{3+}$(aquo) are also evaluated from the fluorescence spectra and compared to the results obtained from the absorption bands.

Semiconductor laser-based absorption spectroscopy for monitoring physical vapor deposition process (증기증착 공정 감시를 위한 반도체 레이저 흡수 분광학)

  • 정의창;송규석;차형기
    • Journal of the Korean Vacuum Society
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    • v.13 no.2
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    • pp.59-64
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    • 2004
  • A study on the semiconductor laser-based atomic absorption spectroscopy was performed for monitoring physical vapor deposition process. Gadolinium metal was vaporized with a high evaporation rate by electron beam heating. Real-time atomic absorption spectra were measured by using tunable semiconductor laser beam at 770-794 nm (center wavelength of 780 nm) and its second harmonic at 388-396 nm. Atomic densities of metal vapor can be calculated from the absorption spectra measured. We plot the atomic densities as a function of the electron beam power and compare with the evaporation rates measured by quartz crystal monitor. We demonstrate that the semiconductor laser-based spectroscopic system developed in this study can be applied to monitor the physical vapor deposition process for other metals such as titanium.

Study on Electronic Absorption and Surface Morphology of Double Layer Thin Films of Phthalocyanines

  • Park, Gyoo-Soon;Heo, Il-Su;Ryu, Il-Hwan;Yim, Sang-Gyu
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.943-946
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    • 2011
  • The electronic absorption and surface morphology evolution of two types of molecular double layer thin films, copper phthalocyanine (CuPc) layer deposited on chloro[subphthalocyaninato]boron(III) (SubPc) layer, denoted as SubPc/CuPc, and vice versa, with various thicknesses were investigated using ultraviolet (UV)-visible spectroscopy and atomic force microscopy (AFM). Both types of double layer structures showed similar broadened absorption patterns in the UV-visible region that were consistent with the fitted spectra following simple linear combination of the single layer absorption spectra of the two materials. In contrast, the surface morphology of double layer structures was dependent on the order of deposition. For the CuPc/SubPc structures, surface morphology was characterized by elongated grains, which are characteristic of SubPc thin films, indicating that the morphological influence of the underlying CuPc layer on the subsequent SubPc layer was not large. For the SubPc/CuPc structures, however, the underlying SubPc layer acted as a morphological template for the subsequently deposited CuPc layer. It was also observed that the grain size of the CuPc layer varied according to the thickness of the underlying SubPc layer.