• Title/Summary/Keyword: Fourier Transform Spectroscopy

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Discrimination of cultivation ages and cultivars of ginseng leaves using Fourier transform infrared spectroscopy combined with multivariate analysis

  • Kwon, Yong-Kook;Ahn, Myung Suk;Park, Jong Suk;Liu, Jang Ryol;In, Dong Su;Min, Byung Whan;Kim, Suk Weon
    • Journal of Ginseng Research
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    • v.38 no.1
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    • pp.52-58
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    • 2014
  • To determine whether Fourier transform (FT)-IR spectral analysis combined with multivariate analysis of whole-cell extracts from ginseng leaves can be applied as a high-throughput discrimination system of cultivation ages and cultivars, a total of total 480 leaf samples belonging to 12 categories corresponding to four different cultivars (Yunpung, Kumpung, Chunpung, and an open-pollinated variety) and three different cultivation ages (1 yr, 2 yr, and 3 yr) were subjected to FT-IR. The spectral data were analyzed by principal component analysis and partial least squares-discriminant analysis. A dendrogram based on hierarchical clustering analysis of the FT-IR spectral data on ginseng leaves showed that leaf samples were initially segregated into three groups in a cultivation age-dependent manner. Then, within the same cultivation age group, leaf samples were clustered into four subgroups in a cultivar-dependent manner. The overall prediction accuracy for discrimination of cultivars and cultivation ages was 94.8% in a cross-validation test. These results clearly show that the FT-IR spectra combined with multivariate analysis from ginseng leaves can be applied as an alternative tool for discriminating of ginseng cultivars and cultivation ages. Therefore, we suggest that this result could be used as a rapid and reliable F1 hybrid seed-screening tool for accelerating the conventional breeding of ginseng.

FT-IR and X-Ray Diffraction Characterization of Melanoidins Formed from Glucose and Fructose with Amino Acid Enantiomers in the Maillard Reaction

  • Kim, Ji-Sang;Lee, Young-Soon
    • Food Science and Biotechnology
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    • v.18 no.2
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    • pp.546-551
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    • 2009
  • The objective of this study was to investigate Fourier transform infrared (FT-IR) spectrometry and the X-ray diffraction (XRD) characterization of melanoidins formed from glucose and fructose with amino acid enantiomers in the Maillard reaction. Before dialysis, FT-IR spectroscopy of all the samples showed that the characteristic absorption intensities appeared as a broad and intense band of the stretching vibration of the -OH group at 3,400/cm for a high pH. The absorption bands of the melanoidins sharply decreased in intensity after dialysis as compared to those before dialysis. In particular, the absorption bands at 992 and 575/cm disappeared. The XRD confirmed that the crystal structure of the melanoidins disappeared after dialysis and a new crystal structure was formed at 9 and $28^{\circ}$ ($2{\theta}$. In particular, broad diffraction peaks were formed in the $10-21^{\circ}$ ($2{\theta}$) range for a high pH, while other sharp diffraction peaks disappeared.

The Production of Hydrophobic Surfaces by the Adsorption of Perfluorocarboxylic Acids onto Metal Oxides (금속 산화물에 플루오르화 카르복시산을 흡착시킨 소수성 표면의 제조)

  • Ha, Ki Ryong;Lee, Myunghee;Chung, Chinkap
    • Applied Chemistry for Engineering
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    • v.16 no.4
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    • pp.542-548
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    • 2005
  • The self-assembled monolayers (SAMs) of perfluorocarboxylic acids were fabricated on several metal oxide powders. Perfluorododecanoic acid and perfluorooctadecanoic acid were used to study the effect of chain length on SAM. Alumina, Tantalia, Titania, and Zirconia were the metal powders used. The formation of the SAMs was confirmed by DRIFT(Diffuse Reflectance Infrared Fourier Transform) spectroscopy. Since the perfluorohydrocarbons are well known for their hydrophobicity, the resulting monolayers are also expected to have high hydrophobicity. The quality of DRIFT spectra of SAMs was dependent on the powder size as well as the element of metal oxides.

Resolution of a Multi-Step Electron Transfer Reaction by Time Resolved Impedance Measurements: Sulfur Reduction in Nonaqueous Media

  • Park, Jin-Bum;Chang, Byoung-Yong;Yoo, Jung-Suk;Hong, Sung-Young;Park, Su-Moon
    • Bulletin of the Korean Chemical Society
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    • v.28 no.9
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    • pp.1523-1530
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    • 2007
  • The first reduction peak of the cyclic voltammogram (CV) for sulfur reduction in dimethyl sulfoxide has been studied using time resolved Fourier transform electrochemical impedance spectroscopic (FTEIS) analysis of small potential step chronoamperometric currents. The FTEIS analysis results reveal that the impedance signals obtained during short potential steps can be resolved into electron transfer reactions of two different time constants in a high frequency region. The FTEIS method provides snap shots of impedance profiles during an earlier phase of the reaction, leading to time resolved EIS measurements. Our results obtained by the FTEIS analysis are consistent with a series of electron transfer and chemical equilibrium steps of a complex reaction, making up an ECE (electrochemical-chemical-electrochemical) mechanism postulated from the results of computer simulation.

Structural, Optical, and Chemical Properties of Cadmium Phosphate Glasses

  • Chung, Jae-Yeop;Kim, Jong-Hwan;Choi, Su-Yeon;Park, Hyun-Joon;Hwang, Moon-Kyung;Jeong, Yoon-Ki;Ryu, Bong-Ki
    • Journal of the Korean Ceramic Society
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    • v.52 no.2
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    • pp.128-132
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    • 2015
  • In this study, we prepared cadmium phosphate glasses with various compositions, given by $xCdO-(100-x)P_2O_5$ (x = 10-55 mol%), and analyzed their Fourier transform infrared spectra, dissolution rate, thermal expansion coefficient, glass transition temperature, glass softening temperature, and optical band gap. We found that the thermal expansion coefficient and dissolution rate increased while the glass transition temperature and glass softening temperature decreased with increasing CdO content. These results suggest that CdO acts as a network modifier in binary phosphate glass and weakens its structure.

Fourier-Transform Infrared Studies of Ionomeric Blend and Ionic Aggregation

  • Lee, Sang-Koog;Jeon, Seung-Ho;Ree, Tai-Kyue;Sohn, Jeong-In
    • Bulletin of the Korean Chemical Society
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    • v.7 no.4
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    • pp.267-271
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    • 1986
  • The ionomeric blend and the ionic aggregation studies by using a Fourier-transform infrared spectroscopy(FT-IR) are presented. Two ionomers were prepared, one is barium polyacrylate and the other is barium polystyrenesulfonate. The blend of the two ionomers of the barium salts shows intermolecular ionic interaction between the carboxylated ionomer and the sulfonated ionomer. This interaction leads to considerable differences between the spectrum of the blend and the sum of the spectra of the pure ionomers. From our results, it is shown that ionic interactions must play an important role in the compatibility of the two ionomers. In the ionic aggregation study, the bands due to asymmetric stretching mode of carboxylate anion(COO-) in the carboxylated ionomer and the ionomer blend increase in intensity with increasing the divalent barium cations. These results indicate the formation of ion pairs. The doublet due to the asymmetric stretching modes of the carboxylate anion(COO-) is concerned with a sort of local structure found in the ion aggregation. By considering a possible structure for multiplets in the blend, the spectral splitting and the frequency shift are well explained.

INVESTIGATION OF EMISSION RATES OF AMMONIA, NITROUS OXIDE AND OTHER EXHAUST COMPOUNDS FROM ALTERNATIVE- FUEL VEHICLES USING A CHASSIS DYNAMOMETER

  • Huai, T.;Durbin, T.-D.;Rhee, S.-H.;Norbeck, J.-M.
    • International Journal of Automotive Technology
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    • v.4 no.1
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    • pp.9-19
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    • 2003
  • Exhaust emissions were characterized for a fleet of 10 alternative-fuel vehicles (AFVx) including 5 compressed natural gas (CNG) vehicles. 3 liquefied petroleum gas (LPG) vehicles and 2 85% methanol/15% California Phase 2 gasoline (M85) vehicles. In addition to the standard regulated emissions and detailed speciation of organic gas compounds, Fourier Transform Infrared Spectroscopy (FTIR) was used to measure ammonia (NH$_3$) and nitrous oxide ($N_2$O) emissions. NH$_3$, emissions averaged 0.124 g/mi for the vehicle fleet with a range from <0.004 to 0.540 g/mi. $N_2$O emissions averaged 0.022 g/mi over the vehicle fleet with range from <0.002 to 0.077 g/mi. Modal emissions showed that both NH$_3$, and $N_2$O emissions began during catalyst light-off and continued as the catalyst reached its operating temperature. $N_2$O emissions primarily were formed during the initial stages of catalyst light-off. Detailed speciation measurements showed that the principal component of the fuel was also the primary organic gas species found in the exhaust. In particular, methane, propane and methanol composed on average 93%, 79%, and 75% of the organic gas emissions, respectively, for the CNG, LPG. and M85 vehicles.

Comparative Biodegradation of HDPE and LDPE Using an Indigenously Developed Microbial Consortium

  • Satlewal, Alok;Soni, Ravindra;Zaidi, Mgh;Shouche, Yogesh;Goel, Reeta
    • Journal of Microbiology and Biotechnology
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    • v.18 no.3
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    • pp.477-482
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    • 2008
  • A variety of bacterial strains were isolated from waste disposal sites of Uttaranchal, India, and some from artificially developed soil beds containing maleic anhydride, glucose, and small pieces of polyethylene. Primary screening of isolates was done based on their ability to utilize high- and low-density polyethylenes (HDPE/LDPE) as a primary carbon source. Thereafter, a consortium was developed using potential strains. Furthermore, a biodegradation assay was carried out in 500-ml flasks containing minimal broth (250ml) and HDPE/LDPE at 5mg/ml concentration. After incubation for two weeks, degraded samples were recovered through filtration and subsequent evaporation. Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric-differential thermogravimetry-differential thermal analysis (TG-DTG-DTA) were used to analyze these samples. Results showed that consortium-treated HDPE (considered to be more inert relative to LDPE) was degraded to a greater extent (22.41% weight loss) in comparison with LDPE (21.70% weight loss), whereas, in the case of untreated samples, weight loss was more for LDPE than HDPE (4.5% and 2.5%, respectively) at $400^{\circ}C$. Therefore, this study suggests that polyethylene could be degraded by utilizing microbial consortia in an eco-friendly manner.

Conservation status assessment of archaeological bone from Fourier Transform Infrared Spectroscopy and histological Analysis (적외선 분광 분석과 조직 분석을 통한 출토 인골의 보존 상태 평가)

  • Lee, Jeongwon;Kim, Sue Hoon;Kim, Yun-Ji;Cho, Eun Min;Kang, Soyeong
    • 보존과학연구
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    • s.35
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    • pp.87-98
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    • 2014
  • Fourier transform infrared spectroscopy(FTIR-ATR) was applied to chemical analysis for conservation status of 10 human bone remains from Joseon Dynasty. The result of crystallinity index (CI) is $4.25{\pm}0.78$, carbonate to carbonate ratio (C/C) is $0.91{\pm}0.04$ and cabonate content (C/P) is $0.19{\pm}0.06$. The higher histological index (HI) confirmed CI and C/P value was increased and C/C value was reduced. While C/C or C/P values analysis is possible. While DNA analysis can be extracted from the bone, C/C values are lower or C/P values are higher was found to the analysis is possible. Chemical assessment of FTIR and histological index consequence is expected to be applicable as a basis for comprehensive understanding of the conservation status excavated bones.

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Relationship between Molecular Structure Characteristics of Feed Proteins and Protein In vitro Digestibility and Solubility

  • Bai, Mingmei;Qin, Guixin;Sun, Zewei;Long, Guohui
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.8
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    • pp.1159-1165
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    • 2016
  • The nutritional value of feed proteins and their utilization by livestock are related not only to the chemical composition but also to the structure of feed proteins, but few studies thus far have investigated the relationship between the structure of feed proteins and their solubility as well as digestibility in monogastric animals. To address this question we analyzed soybean meal, fish meal, corn distiller's dried grains with solubles, corn gluten meal, and feather meal by Fourier transform infrared (FTIR) spectroscopy to determine the protein molecular spectral band characteristics for amides I and II as well as ${\alpha}$-helices and ${\beta}$-sheets and their ratios. Protein solubility and in vitro digestibility were measured with the Kjeldahl method using 0.2% KOH solution and the pepsin-pancreatin two-step enzymatic method, respectively. We found that all measured spectral band intensities (height and area) of feed proteins were correlated with their the in vitro digestibility and solubility ($p{\leq}0.003$); moreover, the relatively quantitative amounts of ${\alpha}$-helices, random coils, and ${\alpha}$-helix to ${\beta}$-sheet ratio in protein secondary structures were positively correlated with protein in vitro digestibility and solubility ($p{\leq}0.004$). On the other hand, the percentage of ${\beta}$-sheet structures was negatively correlated with protein in vitro digestibility (p<0.001) and solubility (p = 0.002). These results demonstrate that the molecular structure characteristics of feed proteins are closely related to their in vitro digestibility at 28 h and solubility. Furthermore, the ${\alpha}$-helix-to-${\beta}$-sheet ratio can be used to predict the nutritional value of feed proteins.