• Journal of the Korean Vacuum Society
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• v.17 no.3
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• pp.215-219
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• 2008

The bonding structure and composition of silicon nitride (SiNx) films were investigated by using Fourier transform infrared spectroscopy (FT-IR). SiNx films were deposited on Si substrate at $340^{\circ}C$ using a conventional PECVD system. The compositions of Si and N in SiNx films were confirmed by using Rutherford backscattering spectroscopy (RBS) and photoluminescence (PL) analysis. The surface morphology of SiNx films was also analyzed by using atomic force microscopy (AFM). It was found that the contents of NH(at. %) is the reverse related with those of SiH corresponding to the result of FT-IR. we conclude that a quantitative analysis on SiNx films can be possible through a precise detection of the contents of H in SiNx films with a FT-IR analysis only.

• Analytical Science and Technology
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• v.5 no.4
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• pp.455-464
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• 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.

• 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.

• Journal of the Optical Society of Korea
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• v.9 no.4
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• pp.151-156
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• 2005

A spatial-domain Fourier Transform (FT) infrared (IR) spectrometer coupled with a PtSi Schottky­barrier IR detector plane was developed in the spectral range of $2.0-2.5{\mu}m$ for noninvasive measurement of analyte concentrations in cell culture media during cell culture processing. A key optical component of the spectrometer is a Savart plate which is a birefringent polarizer generating coherent two rays for interfering. The spectral resolution of the spectrometer was determined as $71cm^{-1}$ (${\~}0.05{\mu}m$ at $2.5{\mu}m$). Clear IR fringe patterns were imaged on the IR detector plane. The feasibility of the spectrometer for our application was investigated by measuring absorbance spectra of glucose and fetal bovine serum (FBS) which are important compounds in cell culture media. Experiment results show that the spectral quality of glucose and FBS was comparable with the standard spectra acquired with a commercial FT-IR spectrometer, presenting the feasibility of the spectrometer to perform analyte measurement in cell culture media.

• 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.

• Journal of Information Display
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• v.2 no.3
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• pp.18-31
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• 2001

We utilize Fourier transform infrared (IR) spectroscopy to probe intramolecular hydrogen bonding in $smectic-C^{\ast}$ liquid crystal phases. Infrared spectra of aligned smectic liquid crystal materials vs. temperature and of isotropic liquid crystal mixtures vs. concentration were measured in homologs, both with and without hydrogen bonding. Hydrogen bonding significantly changes the direction and magnitude of the vibrational dipole transition moments, causing marked changes in the IR dichroic absorbance profiles of hydrogen bonded molecular subfragments. A GAUSSIAN94 computation of the directions, magnitudes, and frequencies of the vibrational dipole moments of molecular subfragments shows good agreement with the experimental data. The results show that IR dichroism can be an effective probe of hydrogen bonding in liquid crystal phases.

• Bulletin of Food Technology
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• v.3 no.3
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• pp.109-122
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• 1990

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.142-145
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• 2007

In order to analyze hyper-spectral properties of Sand and Dust Storm (SDS), dust observation experiment has been performed at the Korea Global Atmosphere Watch Center (KGAW) in Anmyeon form early March to middle of May, 2007. We measured down-welling radiances by using ground-based Fourier Transform Infrared Spectroscopy (FT-IR) at the time of overpass of AIRS. And radiative transfer model simulation has been carried out to estimate the effects of size distribution, components, and altitude of SDS over the high resolution infrared spectrum in the range of 500-1500 $cm^{-1}$ with a line-by-line radiative transfer model and compared them with FT-IR and AIRS/Aqua observing data.

• 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.

• 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.