• Journal of the Korean Chemical Society
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• v.37 no.4
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• pp.371-377
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• 1993

Fourier Transform UV/VIS spectrometer has been modified for emission spectroscopy with the technique of supersonic expansion, in which the unstable molecular radical $CH_3S$ has been generated in a jet by a high voltage DC discharge. The fluorescence spectra of the supersonically cooled radical have been recorded on a Fourier Transform UV/VIS spectrometer. The ratio of signal to noise of the spectra has been improved substantially. Also the rotational structure has been clearly resolved for $CH_3S$ molecular radical.

• 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.

• Journal of the Optical Society of Korea
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• v.14 no.4
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• pp.290-297
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• 2010

The paper reviews progress and future prospects of two kinds of planar waveguide devices; they are (a) silica and silicon photonics multi/demultiplexers for communications and signal processing applications, and (b) a novel waveguide spectrometer based on Fourier transform spectroscopy for sensing applications.

• Journal of the Korean Electrochemical Society
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• v.17 no.2
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• pp.119-123
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• 2014

Here I report on how Fourier Transform Electrochemical Impedance Spectroscopy (FTEIS) overcomes the potential-current linearity problem encountered in the impedance calculation process. FTEIS was first invented to solve the time-related drawback of the conventional impedance technique. The dramatic time reduction of FTEIS enabled the real-time impedance measurement but brought about the linearity problem at the same time. While the conventional method circumvents the problem using the steady-state made by a sufficiently long measurement time, FTEIS cannot because of its real-time function. However, according to the mathematical development reported in this article, the potential step used in FTEIS is proved to avoid the linearity problem. During the step period, the potential and the current are linearized by the electrochemical impedance. Also, Fourier transform of the differentiated potential and current is proved to give the same result of the original ones.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1199-1203
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• 2009

Melamine is a chemical intermediate to manufacture amino resins and plastics, which cannot be used as food additive since it can cause kidney stones. A qualitative determination method of melamine residue in powdered and liquid milk was developed using Fourier transform infrared (FTIR) spectroscopic technique. The calibration sets consisted of 21 standard melamine solutions, in which 1% trichloroacetic acid aqueous solution and acetonitrile (3:1, v/v) were used as solvent. The model was validated using 10 standard melamine solutions which were unused to build up the calibration set. Infrared (IR) absorbance peaks specific to almost all chemical groups in melamine molecule were shown in the spectral range between 1,100 and 1,800/cm. Combined partial least squares (PLS)-$2^{nd}$ derivative calibration model coupled with mean centering (MC) mathematical enhancement showed the highest correlation coefficients ($R^2$>0.99). In brief, the FTIR technique can be used for quantitative analysis of melamine in milk samples.

• Bulletin of the Korean Chemical Society
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• v.15 no.5
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• pp.357-360
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• 1994

The adsorption of cyanide ion on the gold electrode has been investigated by the subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS). The observations made by SNIFTIRS were consistent with those obtained by the polarization modulated Fourier transform infrared spectroscopy. According to the surface selection rule, cyanide ion appeared to adsorb on gold via either carbon or nitrogen lone pair electrons assuming a perpendicular orientation with respect to the metal surface. The possibility of presence of bridge-bound species seemed very infeasible. From the ab initio quantum mechanical calculation, adsorbate-to-metal bonding appeared to occur mainly via the $5{\sigma}$ donation from carbon to Au.

• 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.

• 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.

• Journal of the Korean Society of Costume
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• v.58 no.5
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• pp.211-231
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• 2008

To conserve historic textiles, analyses of textile materials, pollutants and deterioration are prerequisite steps. Based upon analytical results, guides for conservation of historic textiles are established. In analyses of textile materials, pollutants and deterioration, there are chemical methods(burning, solubility and staining), physical methods(microscopy and density) and instrumental analysis(Fourier Transform Infrared Spectroscopy (FT-IR), Fourier Transform Raman Spectroscopy(FT-Raman), Gas Chromatography(GC), Mass Spectroscopy(MS), X-Ray Fluorescence (EDXRF, WDXRF), Energy Dispersive Spectroscopy(EDS), and X-Ray Diffraction(XRD), Tensile Testing Machine etc.). Combination of qualitative and quantitative analyses makes accurate diagnosis of textile condition possible. As examples of analyses and conservation of historic textiles, Chuninsan(19 century) similar to sunshade with handing down historic textile and golden decorative skirt(17 century) with excavated costume are taken.

• International Journal of Concrete Structures and Materials
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• v.7 no.2
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• pp.119-125
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• 2013

Carbonation is a natural ageing process for cement. This study focuses on how the carbonation rate varies with selected hydration times and atmospheric conditions during the early stages of reacting dried cement paste. Diffuse reflection Fourier transform infrared spectroscopy is shown to be a suitable technique to monitor the formation of carbonates in cement. Combined with a previously developed freeze drying technique, carbonation can be studied at specific hydration stages. In ambient air both calcium hydroxide and calcium silicate hydrate (C-S-H) in cement are carbonated. Increased hydration time enhances the carbon dioxide uptake, which indicates that the calcium in the hydration products reacts more easily than the calcium in the clinker phase. In a humid $CO_2$ atmosphere, the carbonation process is so pronounced that it decomposes C-S-H into calcium carbonate and silica. In a moist $N_2$ atmosphere no carbonation occurs, but the sulfate chemistry of the cement seems to be affected due to the formation of ettringite.