• Title/Summary/Keyword: IR spectra

Search Result 848, Processing Time 0.027 seconds

Studies on the Constituents of Chrysanthemum sinense Sabine (Chrysanthemum sinense Sabine의 성분 연구)

  • 김종원
    • YAKHAK HOEJI
    • /
    • v.22 no.2
    • /
    • pp.83-86
    • /
    • 1978
  • A colorless sublime needles (A), $C_{10}H_{10}O_{4}$, mp$142~143\circ$ was isolated from the fresh flowers of Chrysanthemun sinense Sabine in 0.16% yield. Its ir, nmr and mass spectral data suggested that it may have an aromatic methylester structure. Hydrolysis of this substane with 10% sodium hydroxide solution yielded terephthalic acid and methanol. This substance was confirmed as dimethyl terephthalate by comparison of ir and nmr spectra, and TLC and GC behaviors of an authentic sample which was prepared from terephthalic acid by methylation. This is the first report that dimethly terephthalate was isolated in the Composite plants.

  • PDF

Fourier Transform Infrared Spectroscopic Analysis of the Silylated Resist on Silicon Wafers in Semiconductor Lithographic Process (반도체 사진공정에서 실리콘 웨이퍼 위의 Silylated Resist의 Fourier 변환 적외선 분광분석)

  • Kang, Sung Chul;Kim, Su Jong;Son, Min Young;Park, Chun Geun
    • Analytical Science and Technology
    • /
    • v.5 no.4
    • /
    • pp.455-464
    • /
    • 1992
  • Using FT-IR, we determined the depth of silylated layers produced from various gas-phase-silylation conditions was proposed by using Fourier Transform Infrared (FT-IR) spectroscopic analysis. The depth of silylated layer was determined from absorbance measurments of the significant peaks (Si-O-ph, Si-C, Si-H) of FT-IR spectra with background spectrum subtraction method. And the results were compared with thickness measurments of SEM. The results were well agree with SEM. It found to be well suited for determining silylation process window.

  • PDF

Synthesis and Crystal Structure of Blue Phosphorescent mer-Tris(2',6'-difluoro-2,3'-bipyridinato-N,C4') Iridium(III)

  • Jung, Na-Rae;Lee, Eun-Ji;Kim, Jin-Ho;Park, Hyoung-Keun;Park, Ki-Min;Kang, Young-Jin
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.1
    • /
    • pp.183-188
    • /
    • 2012
  • A blue phosphorescent $Ir(dfpypy)_3$ (dfpypy:fluorinated pyridine-pyridine ligand) complex with meridional configuration has been synthesized by newly developed effective method and its solid state structure and photoluminescence are characterized. For this complex, mer-$Ir(dfpypy)_3$, the glass-transition and decomposition temperatures appear at $160^{\circ}C$ and $384^{\circ}C$ respectively in TGA and DSC experiments, which indicates that this complex has high thermal stability. In a crystalline structure, an average Ir-C bond length of mer-$Ir(dfpypy)_3$ is slightly longer than that of fac-$Ir(dfpypy)_3$, which assumed to be due to the weak trans-influence. The absorption and emission spectra are observed more red-shifted in mer-$Ir(dfpypy)_3$ than fac-$Ir(dfpypy)_3$. In addition, the former is readily oxidized than the latter in electrochemical behavior.

FT-IR and XRD Analyses of Commercial Methionine-Mineral Chelates

  • Han, Jae-Hong;Chi, Yong-Seok;Shin, Bok-Kyu;Kim, Sang-Kyu;Paik, In-Kee
    • Journal of Applied Biological Chemistry
    • /
    • v.49 no.1
    • /
    • pp.8-10
    • /
    • 2006
  • Compositions of methionine-metal chelates have been investigated by FT-IR and XRD studies to elucidate their molecular structures. It was concluded that Copamin and Zincamin contain a high percentage of crystalline products, presumably 2:1 Methionine-Cu or Zn complexes. On the contrary, FT-IR and XRD spectra of Ferramin didn't show any characteristics of the chelate and it was concluded to contain major components of starting $FeSO_4$ and methionine without chelation.

DIAMOND-LIKE CARBON FILMS FOR ANTIREFLECTION COATINGS OF GERMANIUM INFRATED OPTICAL LENSES

  • Kim, Seong-Young;Lee, Sang-Hyun;Lee, Jai-Sung
    • Journal of the Korean institute of surface engineering
    • /
    • v.32 no.3
    • /
    • pp.461-466
    • /
    • 1999
  • Diamond-like carbon(DLC) films were directly deposited onto germanium(Ge) witness pieces and lenses by a capacitively coupled 13.56 MHz RF glow discharge plasma with $CH_4$ gas. The characterizations of DLC films were measured using a Raman and FTIR spectrometer. The configuration of Raman and FTIR spectra had a traditional shape. The IR transmittance was measured using an IR spectrophotometer. The maximum values of the IR transmission of Ge with the DLC/Ge/DLC, DLC/Ge/BBAR (broad band antireflection), DLC/Ge, and BBAR/Ge structures are 98%, 93%, 64%, and 63.5%, respectively, which come up to the theoretical values. The uniform DLC films were obtained by a rotation of the cathode at certain conditions.

  • PDF

HIGH-RESOLUTION NEAR-INFRARED SPECTRA OF NEARBY QUASARS

  • Le, Huynh Anh Nguyen;Pak, Soojong;Im, Myungshin;Ho, LuisC.
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.37 no.2
    • /
    • pp.91-91
    • /
    • 2012
  • We present high-resolution near-infrared host galaxy spectra of low-z quasars, PG0844+349 (z=0.064), PG1226+023 (z=0.158), and PG1426+015 (z=0.086). The observation was done by using the near-IR high resolution echelle spectrometer, IRCS, at the SUBARU 8.2 m telescope. The full width at half maximum of the point spread function was about 0.3 arcsec by using an Adaptive Optics system, which can effectively resolve the quasar spectra from the host galaxy spectra. The signal-to-noise ratios are increased by the total exposure time up to several hours per targets and the development of data reduction method. We compare our results to the stellar spectra library and sample spectra from Dasyra et al. (2007) and Watson et al. (2008). The identified spectral lines will be used to study the physical mechanism of quasars, and the velocity dispersions of the stars in the bulge of the host galaxy.

  • PDF

Carbohydrate and lipid spectroscopic molecular structures of different alfalfa hay and their relationship with nutrient availability in ruminants

  • Yari, Mojtaba;Valizadeh, Reza;Nnaserian, Abbas Ali;Jonker, Arjan;Yu, Peiqiang
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.30 no.11
    • /
    • pp.1575-1589
    • /
    • 2017
  • Objective: This study was conducted to determine molecular structures related to carbohydrates and lipid in alfalfa hay cut at early bud, late bud and early flower and in the afternoon and next morning using Fourier transform infrared spectroscopy (FT/IR) and to determine their relationship with alfalfa hay nutrient profile and availability in ruminants. Methods: Chemical composition analysis, carbohydrate fractionation, in situ ruminal degradability, and DVE/OEB model were used to measure nutrient profile and availability of alfalfa hay. Univariate analysis, hierarchical cluster analysis (CLA) and principal components analysis (PCA) were conducted to identify FT/IR spectra differences. Results: The FT/IR non-structural carbohydrate (NSCHO) to total carbohydrates and NSCHO to structural carbohydrate ratios decreased (p<0.05), while lignin to NSCHO and lipid CH3 symmetric to CH2 symmetric ratios increased with advancing maturity (p<0.05). The FT/IR spectra related to structural carbohydrates, lignin and lipids were distinguished for alfalfa hay at three maturities by PCA and CLA, while FT/IR molecular structures related to carbohydrates and lipids were similar between alfalfa hay cut in the morning and afternoon when analyzed by PCA and CLA analysis. Positive correlations were found for FT/IR NSCHO to total carbohydrate and NSCHO to structural carbohydrate ratios with non-fiber carbohydrate (by wet chemistry), ruminal fast and intermediately degradable carbohydrate fractions and total ruminal degradability of carbohydrates and predicted intestinal nutrient availability in dairy cows ($r{\geq}0.60$; p<0.05) whereas FT/IR lignin to NSCHO and CH3 to CH2 symmetric stretching ratio had negative correlation with predicted ruminal and intestinal nutrient availability of alfalfa hay in dairy cows ($r{\geq}-0.60$; p<0.05). Conclusion: FT/IR carbohydrate and lipid molecular structures in alfalfa hay changed with advancing maturity from early bud to early flower, but not during the day, and these molecular structures correlated with predicted nutrient supply of alfalfa hay in ruminants.

Fluorescence Behavior of Benzo[f]Quinoline Doped In Lpd Silica Thin Films

  • Mabuchi, Toshiaki;Suzuki, Satoshi;Nakajima, Tsuyoshi;Ino, Juichi;Takemura, Kazuo;Shimizu, Etsuro
    • Journal of Photoscience
    • /
    • v.5 no.3
    • /
    • pp.105-109
    • /
    • 1998
  • By using the liquid -phase-deposition (LPD) process, which has a potetnial of preparing organic inorganic composite materials, samples doped with benzo[f]quinoline (BfQ)into silica thia films wre prepared. We observed the fluorescene and fluorescene excitation spectra of the samples, as well as the fluorescence lifetimes and time-resoluved fluorescence spectra. The comparison of thefluorescence spectra in pH-controlled buffer solutions yields the results that the dominant species of BfQ in the LPD silica films is a protonated one. The fluorescence band assigned to a hydrogen-bonded species was observed on the samples prepared from the dipping solutions of 3 and 2 M hexafluorosilicic acid. The band assignment was confirmed by the fluorescence lifetime measurement. The FT-IR M hexaflurosilicic acid. The band assignment was confirmed by the flurescence lifetime meausurement. The FT-IR data proved the existence of included water in silica films prepared from the LPD process. The appearance of the band corresponding to the hydrogen-bonded species within LPD silica phases was explained by the proesence of included water. Depending on the preparation conditions of LPD silica films, the band assigned to protonated species shows bad shifts in a wavenumber region between the peak of hydrogen-bonded and typical protonated species. This implies that there is some distribution of steric conformation of protonated species of BfQ interacting with adsorbing sites of LPD silica. The time -resolved fluorescence spectra suggest that some relaxation process is involved in the conformation of BfQ doped into the solid phase of LPD silica.

  • PDF

A quantitative determination of surfactant mixtures by FT-IR (FT-IR을 이용한 계면활성제 혼합물의 정량)

  • 최종근;노경원
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.21 no.2
    • /
    • pp.129-139
    • /
    • 1995
  • To confirm the usefulness of partial least-squares(PLS) and multiple scattering correction(MSC) method for quantitation of surfactants in [quantitative methods using FT-lR, reconsitituted mixtures of LAS, MES and ELA-9 were tested. Each mixture was dissolved in 50% EtOH, dried, and applied to the KBr cell. From the IR spectra of these mixture, the variance spectrum was obtained. After repeated calibrations for the various regios of this spectrum, we found that 1245-1130cm-1 and 1070-1010cm-1 showed the strong correlation with each component of the sample mixture: all the correlation coefficients were 1.000 and quantitative errors did not exceed 0.32%. From this result, we concluded that PLS method and MSC method are very useful and can be successfully applied to Quality control.

  • PDF