• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1628-1628
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• 2001

Near infrared (NIR) spectroscopy is a powerful technique for non-destructive analysis that can be obtained in a wide range of environments. Recently, NIR measurements have been utilized as probe for quantitative analysis in agricultural, industrial, and medical sciences. In addition, it is also possible to make practical application on NIR for molecular structural analysis. In this work, Fourier transform near infrared (FT-NIR) measurements were carried out to utilize extensively in the relative amounts of different secondary structures were employed, such as Iysozyme, concanavalin A, silk fibroin and so on. Several broad NIR bands due to the protein absorption were observed between 4000 and $5000\;^{-1}$. In order to obtain more structural information from these featureless bands, second derivative and Fourier-self-deconvolution procedures were performed. Significant band separation was observed near the feature at $4610\;^{-1}$ ,. Particularly the peak intensity at $4525\;^{-1}$ shows a characteristic change with thermal denaturation of fibroin. The structural information can be also obtained by mid-IR and CD spectral. Correlation of NIR spectra with protein structure is discussed.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.11-16
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• 2005

Humic substances(HS) from raw and process waters at a conventional water treatment plant were isolated and extracted by physicochemical fractionation methods to investigate their characteristics. They are characterized for their functionality, chemical composition, and spectroscopic characteristics using FT-IR(Fourier transform infrared) and $^1H-NMR$(proton nuclear magnetic resonance) spectroscopy. Humic fraction gradually decreased from 47.2% to 26.4%(from 0.97 to 0.54 mgC/L) through conventional water treatment processes. Concentration of phenolic groups in the HS fraction gradually decreased from 60.5% to 21.8%(from 12.2 to $6.0\;{\mu}M/L$ as phenolic-OH) through water treatment. In the case of carboxylic groups, the concentration increased from 39.5% to 46.9%(from 7.9 to $10.6\;{\mu}M/L$ as COOH) by pre-chlorination, but gradually decreased to 34.2%($9.4\;{\mu}M/L$ as COOH) through sedimentation and sand filtration. From the results of the FT-IR and $^1H-NMR$ spectra of HS, the content of carboxylic groups increased and ratio of aliphatic protons to aromatic protons($P_{Al}/P_{Ar}$) also increased through water treatment, which indicated the increase of aliphatic compounds.

• Journal of the Korean Ceramic Society
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• v.51 no.4
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• pp.350-356
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• 2014

Recently, Chemical Vapor Deposition (CVD) synthetic diamonds have been introduced to the jewelry gem market, as CVD technology has been making considerable advances. Unfortunately, CVD diamonds are not distinguishable from natural diamonds when using the conventional gemological characterization method. Therefore, we need to develop a new identification method that is non-destructive, fast, and inexpensive. In our study, we employed optical microscopy and spectroscopy techniques, including Fourier transform infra-red (FT-IR), UV-VIS-NIR, photoluminescence (PL), micro Raman, and cathodoluminescent (CL) spectroscopy, to determine the differences between a natural diamond (0.30 cts) and a CVD diamond (0.43 cts). The identification of a CVD diamond was difficult when using standard gemological techniques, UV-VIS-NIR, or micro-Raman spectroscopy. However, a CVD diamond could be identified using a FT-IR by the Type II peaks. In addition, we identified a CVD diamond conclusively with the uneven UV fluorescent local bands, additional satellite PL peaks, longer phosphorescence life time, and uneven streaks in the CL images. Our results suggest that using FT-IR combined with UV fluorescent images, PL, and CL analysis might be an appropriate method for identifying CVD diamonds.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.3
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• pp.183-189
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• 2013

The chalcogenide glass has superior optical properties in IR region transmittances. We have determined the composition of GeSbSe chalcogenide glass for the application of good IR lenses, resulting in the composite rate of $Ge_{19}Sb_{23}Se_{58}$. The optical, structural, thermal and physical properties were measured by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Differential scanning calorimeter (DSC), X-ray computed tomography (X-ray CT) respectively. The fabrication of the chalcogenide glass lens for infrared optics applications was proposed using a diamond turning machining technology which is known as the suitable ways for the production cost reduction and the accurate fabrication process control.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.229.1-229.1
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• 2010

We investigated the effect of chemical acid treatments on hydrogen storage behaviors of the ordered mesoporous carbons (MCs). The surface functional groups and specific elements of the MCs were characterized with Fourier Transform Infrared (FT-IR) spectrometry and X-ray photoelectron spectroscopy (XPS). Also, the changes in the surface functional groups of the MCs were quantitatively detected by Boehm's titration method. The structural properties of the MCs were investigated using X-ray diffraction (XRD). The hydrogen adsorption capacity of the MCs was evaluated by means of adsorption isotherms at 77 K/1 bar. The formation of surface functional groups by the acidic treatments could influence on the hydrogen storage capacity of the MCs.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.540-540
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• 2013

In this studying, we investigated the basic properties of N-doped plasma polymer. The N-doped ethylcyclohexane plasma polymer thin films were deposited by radio frequency (13.56 MHz) plasma-enhanced chemical vapor deposition method. Ethylcyclohexenewas used as organic precursor (carbon source) with hydrogen gas as the precursor bubbler gas. Additionally, ammonia gas [NH3] was used as nitrogen dopant. The as-grown polymerized thin films were analyzed using ellipsometry, Fourier-transform infrared [FT-IR] spectroscopy, Raman spectroscopy, FE-SEM, and water contact angle measurement. The ellipsometry results showed the refractive index change of the N-doped ethylcyclohexene plasma polymer film. The FT-IR spectrashowed that the N-doped ethylcyclohexene plasma polymer films were completely fragmented and polymerized from ethylcyclohexane.

• Journal of Conservation Science
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• v.5 no.2 s.6
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• pp.45-50
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• 1996

Silk fibers excavated at Fujinoki mounted tomb, Shimoikeyana mounted tomb and Kuriyama site were examined using FT-IR microscope and two peaks called amide I and II present in modern silk fibers were compared with those of excavated fibers. It was found that amide ground in a polymer molecule decreased with the progress of degradation and peak intensity of amide group in infrared spectrum decreased correspondingly. The advantages of FT-IR microscopy for the analysis of organic remains in archaeological view point were evaluated and it was concluded that the systematic investigation of spectral change due to the degradation of respective material is essential.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.860-863
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• 2005

The microcapsules containing fragrant oil as functional material were prepared by in-situ polymerization with prepolymer that was made from melamine-formaldehyde (MF) as wall material of microcapsules. The effects of polymerization variables, such as the nature and concentration of surfactants, stirring rate, and stirring time, on the size and distribution of the particles were investigated. Fourier transform-infrared spectroscopy (FT-IR), thermal analysis, particle size analysis, scanning electron microscopy (SEM) observation were used to investigate the characteristics of microcapsules. Through the FT-IR and SEM analysis, we found that the prepared microcapsules were containing fragrant oil and the shape of particle was spherical. The nature and concentration of surfactants, stirring rate, and stirring time had profound effects on the particle size and particle size distribution.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.21-30
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• 2008

To understand the complex hydrogen bonding structure, several phenolic derivatives and benzoxazine model compounds are synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR). The estimation of molar extinction coefficients for various types of hydrogen bonding species is systematically carried out by the curve-resolving of FT-IR spectra. The distribution of hydrogen bonding species in benzoxazine model dimers is quantitatively analyzed. It is revealed that benzoxazine dimers and BA-a polybenzoxazine are mainly composed of intramolecular interaction rather than intermolecular interaction.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.8
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• pp.1161-1169
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• 1999

This research was aimed to identify the artifact type and their characteristics of the textile related materials excavated from Koryo Dynasty tombs of Hyungok-ni Danyang. Microscopy solubility test energy dispersive X-ray spectroscopy(EDS) and fourier transform infrared spectroscopy (FT-IR) fabric density test were used for the identification and when necessary standard samples were made in order to compare its characteristics with hose of the original artifact, the result indicated that the artifacts included both textile and paper. Artifacts from Burial 14 were comprised of textile fragments FT-IR and the solubility test conducted on the artifact indicated that the textiles were made with ramie woven with plain weave technique in a fairly loose fabric density. Rest of the artifacts were all comprised of paper.