• Title/Summary/Keyword: Fourier Transform Infrared

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Rapid discrimination of commercial strawberry cultivars using Fourier transform infrared spectroscopy data combined by multivariate analysis

  • Kim, Suk Weon;Min, Sung Ran;Kim, Jonghyun;Park, Sang Kyu;Kim, Tae Il;Liu, Jang R.
    • Plant Biotechnology Reports
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    • v.3 no.1
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    • pp.87-93
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    • 2009
  • To determine whether pattern recognition based on metabolite fingerprinting for whole cell extracts can be used to discriminate cultivars metabolically, leaves and fruits of five commercial strawberry cultivars were subjected to Fourier transform infrared (FT-IR) spectroscopy. FT-IR spectral data from leaves were analyzed by principal component analysis (PCA) and Fisher's linear discriminant function analysis. The dendrogram based on hierarchical clustering analysis of these spectral data separated the five commercial cultivars into two major groups with originality. The first group consisted of Korean cultivars including 'Maehyang', 'Seolhyang', and 'Gumhyang', whereas in the second group, 'Ryukbo' clustered with 'Janghee', both Japanese cultivars. The results from analysis of fruits were the same as of leaves. We therefore conclude that the hierarchical dendrogram based on PCA of FT-IR data from leaves represents the most probable chemotaxonomical relationship between cultivars, enabling discrimination of cultivars in a rapid and simple manner.

Study on Rapid Measurement of Wood Powder Concentration of Wood-Plastic Composites using FT-NIR and FT-IR Spectroscopy Techniques

  • Cho, Byoung-kwan;Lohoumi, Santosh;Choi, Chul;Yang, Seong-min;Kang, Seog-goo
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.6
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    • pp.852-863
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    • 2016
  • Wood-plastic composite (WPC) is a promising and sustainable material, and refers to a combination of wood and plastic along with some binding (adhesive) materials. In comparison to pure wood material, WPCs are in general have advantages of being cost effective, high durability, moisture resistance, and microbial resistance. The properties of WPCs come directly from the concentration of different components in composite; such as wood flour concentration directly affect mechanical and physical properties of WPCs. In this study, wood powder concentration in WPC was determined by Fourier transform near-infrared (FT-NIR) and Fourier transform infrared (FT-IR) spectroscopy. The reflectance spectra from WPC in both powdered and tableted form with five different concentrations of wood powder were collected and preprocessed to remove noise caused by several factors. To correlate the collected spectra with wood powder concentration, multivariate calibration method of partial least squares (PLS) was applied. During validation with an independent set of samples, good correlations with reference values were demonstrated for both FT-NIR and FT-IR data sets. In addition, high coefficient of determination (${R^2}_p$) and lower standard error of prediction (SEP) was yielded for tableted WPC than powdered WPC. The combination of FT-NIR and FT-IR spectral region was also studied. The results presented here showed that the use of both zones improved the determination accuracy for powdered WPC; however, no improvement in prediction result was achieved for tableted WPCs. The results obtained suggest that these spectroscopic techniques are a useful tool for fast and nondestructive determination of wood concentration in WPCs and have potential to replace conventional methods.

Direct Determination of Soil Nitrate Using Diffuse Reflectance Fourier Transform Spectroscopy (DRIFTS) (중적외선 분광학을 이용한 토양 내의 질산태 질소 정량분석)

  • Choe, Eunyoung;Kim, Kyoung-Woong;Hong, Suk Young;Kim, Ju-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.4
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    • pp.267-272
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    • 2008
  • Mid-infrared (MIR) spectroscopy, particularly Fourier transform infrared spectroscopy (FTIR), has emerged as an important analytical tool in quantification as well as identification of multi-atomic inorganic ions such as nitrate. In the present study, the possibility of quantifying soil nitrate via diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) without change of a sample phase or with least treated samples was examined. Four types of soils were spectrally characterized in terms of unique bands of soil contents and interferences with nitrate bands in the range of $2000-1000cm^{-1}$. In order to reduce the effects of soil composition on calibration model for nitrate, spectra transformed to the 1st order derivatives were used in the partial least squared regression (PLSR) model and the classification procedure associated with input soil types was involved in calibration system. PLSR calibration models for each soil type provided better performance results ($R^2$>0.95, RPD>6.0) than the model considering just one type of soil as a standard.

Properties of Current due to Voltage in Heat Conductive Silicone Rubber (열전도성 실리콘 고무의 전압-전류 특성)

  • Lee, Sung-Ill
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.9
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    • pp.576-581
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    • 2014
  • This study used the heat conductive silicone rubber sample of 0.95 mm thickness to research the properties of current by changing voltage. When the 1, 10, 30, 60, and 90 minute have passed, the running current has been measured through the applied voltage range of 200 V~800 V on setting temperature of $110^{\circ}C{\sim}170^{\circ}C$. As the temperature increased in applied voltage of 800 V, so did the current value according to time in proportion to the increasing temperature. In an analysis of FT-IR (fourier transform infrared) spectrum, the hydroxyl radicals group(O-H) was created by effects of the hydrogen that methyl group is eliminated by addition of the cross-linking agent peroxide.

Preparation and Characterization of Thin Films by Plasma Polymerization of Hexamethyldisiloxane

  • Lee, Sang-Hee;Lee, Duck-Chool
    • Electrical & Electronic Materials
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    • v.11 no.10
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    • pp.66-71
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    • 1998
  • Plasma polymerized hexamethyldisiloxane (PPHMDSO) thin films were produced using an electrode capacitively coupled apparatus. Fourier transform infrared spectroscopy analysis indicated that the thin film spectra are composed not only of the corresponding monomer bands but also of several new bands. Auger electron spectroscopy analysis indicated that the permeation depth of aluminum into the films is ca. 30nm when top electrode is deposited by evaporation aluminum. The increase of relative dielectric constant and decrease of dielectric loss tangent with the discharge power is originated from high cross-link of the films.

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Analysis of sampling noise effect of Interferometer on FTIR Spectrometer (FTIR 분광용 간섭계의 샘플링 잡음 영향 분석)

  • Bae, Hyo-Wook;Park, Do-Hyun;Ra, Sung-Woong;Choi, Seung-Ki
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.4
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    • pp.10-17
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    • 2007
  • FTIR(Fourier Transform Infrared) spectrometry is a useful method to obtain infrared spectra of materials in gas phase by registering the interferogram of a target material using an interferometer, and then performing a Fourier transform on the interferogram to obtain the spectrum. In this paper, sampling noise effect on signal processing of the rapid scan interferometer was studied with relation to sampling the interferogram points at the improper location and empirically verified.

Damage Pattern Analysis of Voltage Cabinet Panel due to Flame (분전반의 화염에 의한 소손패턴 분석)

  • Kim, Dong-Ook;Lee, Ki-Yeon;Kim, Hyang-Kon;Kim, Man-Geon
    • Journal of Korean Institute of Fire Investigation
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    • v.11 no.1
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    • pp.37-40
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    • 2008
  • This paper deals with damage patterns of cabinet panel for low voltage deteriorated by flame. In order to analyze damage patterns, we used Metallurgical Microscope, x-ray system, and Fourier Transform Infrared spectroscopy. Firstly, Metallurgical microscope was used for analysis of electrical causes, such as electric short and overload Secondly, X-ray system was used for analysis of internal characteristics of circuit breakers. Lastly, Fourier Transform Infrared spectroscopy was used for analysis of damage direction by flame.

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Damage Pattern Analysis of Low Voltage Cabinet Panel due to Flame (저압 분전반의 화염에 의한 소손패턴 분석)

  • Kim, Dong-Ook;Lee, Ki-Yeon;Kim, Dong-Woo;Gil, Hyoung-Jun;Kim, Hyang-Kon
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.04a
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    • pp.269-272
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    • 2008
  • This paper deals with damage patterns of cabinet panel for low voltage deteriorated by flame. In order to analyze damage patterns, we used Metallurgical Microscope, x-ray system, and Fourier Transform Infrared spectroscopy. Firstly, Metallurgical microscope was used for analysis of electrical causes, such as electric short and overload. Secondly, X-ray system was used for analysis of internal characteristics of circuit breakers. Lastly, Fourier Transform Infrared spectroscopy was used for analysis of damage direction by flame. The following results were obtained.

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Study on the Generation of Leakage Current by the Fourier Transform Infrared Analysis (푸리에변환 적외선분광분석법에 의한 누설전류의 발생 원인에 대한 연구)

  • Oh, Teresa
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.6
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    • pp.514-519
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    • 2007
  • The surfaces of $SiO_2$ films were treated by PMMA diluted solutions, and analyzed the chemical shift from Fourier Transform Infrared Spectrometer. The $SiO_2$ film treated by PMMA diluted solution changed the properties of the surface, and showed the blue and red shift according to the concentration of PMMA. The C-H bond elongation effect due to the high electro-negative atom chlorine showed the red shift, and makes the final material with the cross-link structure. The leakage current was efficiently reduced at the sample No 7 with the red shift, witch depends on the electron deficient group.