• Journal of Conservation Science
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• v.33 no.1
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• pp.35-42
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• 2017

The Yeongheungdo shipwreck was excavated in the sea of Seomeopbeol, Ongjin-gun, Incheon, Korea. Chemical characterization of timbers from the shipwreck occurred via maximum moisture content, chemical composition, FT-IR, solid state $^{13}C$ NMR, and XRD analyses. As maximum moisture content of the outer part of the timbers averaged 623%, a phenomenon in that lignin increased relatively, according to the decrease in cellulose, and the ash content increased, which is typical of waterlogged archaeological wood was shown. The results from the FT-IR and solid state $^{13}C$ NMR analyses showed that the cellulose band of the outer part had disappeared or had remarkably decreased. In addition, the bands assigned to lignin dramatically increased. However, regarding the inner part of the timbers, hemicellulose and some crystalline cellulose and amorphous cellulose bands decreased. Therefore, a large difference exists between the degradation levels of the outer and inner parts of the timbers of the Yeongheungdo shipwreck.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.249-254
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• 1998

To synthesize cation exchange resin which has thermal stability, the sulfonated poly(ether ether sulfone) (SPEES) was obtained by sulfonation after synthesis of poly(ether ether sulfone) (PEES). It was prepared from hydroquinone and dichlorophenyl sulfone. From FT-IR results, the sulfonation was confirmed by the bands of asymmetric O=S=O stretching of $SO_3Na$ Na group at $1140cm^{-1}$ and S-C stretching at $621cm^{-1}$. The optimum condition of the sulfonation of PEES, based on IR absorbance, was 3 hr of reaction time, $30^{\circ}C$ of reaction temperature, and chlorosulfonic acid of 150 mol%. Ion exchange capacities calculated by the IR absorbance of PEES sulfonated in optimum condition was 6.2 meq/g, which was nearly similar to the ion exchange capacity calculated by titration. When the metal ion was adsorved, small brain, lump, hulled millet shape and compact surface, were observed in the morphology of SPEES.

• Journal of the Mineralogical Society of Korea
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• v.6 no.2
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• pp.105-115
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• 1993

$M{\ddot{o}}ssbauer$ and Infrared absorption spectra of the iron-bearing tourmaline minerals show that the ferrous and ferric ions occupy the Y and Z octahedral sites. The Fe ions are almost ferrous, predominantly partitioning into Y site and partly take in Z site. The $Fe^{2+}$ content of the Z sites in brownish black tourmaline minerals are higher than that in blue/green tourmaline minerals. Therefore, 720 nm peak of brownish black samples is broader than that of blue/green samples in optical spectra. All of the blue/green tourmaline minerals used in experiment have only $Fe^{2+}$ ion. The IR spectra of tourmaline depend on the cation environments around OH groups, as also evidenced by their chemical analyses. There appear no difference in IR spectrum between O(1)H and O(3)H binding characters in the heat-treated samples. But the characteristic $3565cm^{-1}$ peak appears in the ferrous hydroxyl bearing silicates, where dehydroxylation temperature for OH coordinated to $Fe^{2+}$ is $700{\sim}800^{\circ}C$.

• Polymer(Korea)
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• v.31 no.5
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• pp.393-398
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• 2007

We studied the mechanism of liquid crystal alignment on polyvinylfluorocinnamate (PVCN-F) films which were irradiated by UV using polarized fourier transform infrared (FT-IR) spectroscopy and ultraviolet/visible (UV/Vis) spectroscopy. UV irradiation of PVCN-F films caused decrease of vinylene -C=C- stretching peak area at $1638cm^{-1}$ and shift of conjugated C:0 stretching vibration at $1712cm^{-1}\;to\;1734cm^{-1}$ which is caused by nonconjugated C=O stretching nitration. To study the orientation direction of 5CB liquid crystal (LC) molecules in the liquid crystal cell with PUV irradiation, rubbing treatment or without any treatment on the PVCN-F alignment layer, we used polarized FT-IR dichroism technique. We successfully measured 5CB LC alignment directions, which are perpendicular to the irradiated PUV polarization direction and parallel to the rubbing direction in the liquid crystal cell without using dichroic dyes.

• Polymer(Korea)
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• v.26 no.2
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• pp.209-217
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• 2002

We studied the mechanism of orientation of polyimide molecules which were irradiated by polarized UU (PUV) using polarized Fourier transform infrared (FT-IR) spectroscopy and ultraviolet (UV) spectroscopy, According to the measured UV spectra, we found PI films mainly absorb UV light less than 350 nm wavelength, therefore, UV light less than 360 nm induces photochemical reaction of PI. PUV irradiation of PI films caused decrease of all peak intensities in the FT-IR spectra. except the newly formed broad peak at $3244 cm^{-1}$, due to degradation of the PI molecules. The remaining PI molecules after photo-degradation showed predominantly perpendicular molecular orientation to the irradiated PUV polarization direction, due to the preferential degradation of PI molecules parallel to irradiated PUV polarization direction. However the rubbing of PI films induced reorientation of the PI molecules parallel to the rubbing direction. We also investigated the alignment of the liquid crystal by rubbing or PUV irradiation. Liquid crystals align perpendicular to the PUV polarization direction and parallel to the rubbing direction.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.17-26
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• 2008

The Madagascar garnets wear mainly found as a porphyroblast in gneiss and classified into rhodolite, purple almandine, and brown almandine based on compositional characteristics and color. UV-visible analysis strong absorption bands, 400, 428, 504, 521, and 572 nm, were observed for rhodolite and purple almandine, and main absorption bands of 433 and 502 nm observed for brown almandine. For FT-IR analysis a strong absorption band of $640\;cm^{-1}$ was observed for rhodolite, two strong bands of 628 and $651\;cm^{-1}$ observed for brown almandine, and two weak absorption bands of 635 and $653\;cm^{-1}$ observed for purple almandine. Single distinct absorption band, $3552\;cm^{-1}$, was observed only for rhodolite. It is possible to distinguish rhodolite from purple or brown almandine by considering overall characteristics of the rhodolite such as color, RI, UV-visible absorption, FTIR absorption etc.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.5
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• pp.483-491
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• 1992

Plasma silicon oxynitride film has been applied as a final passivation layer for semiconductor devices, because it has high resistance to humidity and prevents from alkali ion's penetration, and has low film stress. Structure properties of plasma silicon oxynitride film have been studied experimentally by the use of FT-IR, AES, stress gauge and ellipsometry. In this experiment,Si-N bonds increase as NS12TO/(NS12TO+NHS13T) gas ratio increases. Peaks of Si-N bond, Si-H bond and N-H bond were shifted to high wavenumber according to NS12TO/(NS12TO+NHS13T) gas ratio increase. Absorption peaks of Si-H bond were decreased by furnace anneal at 90$0^{\circ}C$. The atomic composition of film represents that oxygen atoms increase as NS12TO/(NS12TO+NHS13T) gas ratio increases, to the contrary, nitrogen atoms decrease.

• Journal of the Mineralogical Society of Korea
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• v.21 no.2
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• pp.117-127
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• 2008

The characteristics of phosphate adsorption-desorption on kaolinite was studied by batch adsorption experiments and detailed adsorbed state of phosphate on kaolinite surface was investigated using ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared) spectroscopy. The phosphorous contents were measured using UV-VIS-IR spectrophotometer with 820 nm wavelength. The adsorbed P was generally increased with increasing pH value in the range of pH 4 to pH 9, however it is not distinct. Moreover the adsorbed P was significantly changed with different initial phosphate concentration. The adsorption isotherms were well fitted with the Langmuir equation, Temkin equation, and Freundlich equation in descending order. The maximum Langmuir adsorption capacity of kaolinite KGa-2 is 232.5 ($204.1{\sim}256.5$) mg/kg and has very higher value than that of kaolinite KGa-1b. Most of adsorbed phosphate on kaolinite were not easily desorbed to aqueous solution, but might fixed on kaolinite surface. However it needs further research about the exact desorption experiment. It was impossible to recognize phosphorous adsorption bands on kaolinite in ATR-FTIR spectrum from kaolinite bands themselves, because the absorption peaks of phosphorous have very similar positions with those of kaolinite, and the intensities of the former were very weak in comparison with those of the latter.

• Analytical Science and Technology
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• v.26 no.4
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• pp.245-255
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• 2013

Identification of paint on victim's clothing and a vehicle are valuable for forensic examination when investigating hit-and-run accidents. Automotive paints on clothes are used to prove a victim caused by traffic accident and to identify a suspected vehicle. The comparison of transferred paints between victim's vehicle and suspected vehicle can be an important evidence in reconstructing the accident situation and in discovering the truth. The paints such as white, yellow, red, blue, or black are hard to examine particle shape under a stereomicroscope because of it is not included aluminum, pearl, and mica flakes in the pigments. The aim of this study under forensic aspect is to compare pigment among basecoat layers of solid paints by identifying inorganic elemental compositions and binder resins of pigments using by micro-FT-IR and micro-XRF spectrometer. The pigment samples were analyzed by using two methods of FT-IR: Reflectance and ATR method. Two methods of FT-IR were useful in discriminating binder resins of pigments by comparing characteristic peaks and patterns of spectra. Also, XRF spectrometer could identify the elemental compositions in inorganic pigments of trace paints which are difficult to compare the identification by FT-IR.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.5
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• pp.9-15
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• 2000

The 3 ${\mu}{\textrm}{m}$-thick PVDF (polyvinylidene fluoride) thin film have been prepared using physical vapor deposition with electric field, and its FT-IR spectrum, dielectric property and electric conduction phenomenon have been investigated. Since the characteristic peaks are detected at 509.45 ［$cm^{-1}$ /］ and 1273.6 ［$cm^{-1}$ /］in the FT-IR spectrum, we are confirmed that the $\beta$ -phase is dominant in the PVDF thin film. In the results of dielectric properties, the PVDF thin film shows anomalous dispersion, i.e. gradual decrease of dielectric constant with increase of frequency, and also that the dielectric absorption point changes from 200 Hz to 7000 Hz with increasing temperature of thin film, which is consistent with the Debye's theory. The activation energy ( $\Delta$H) obtained from temperature dependence of dielectric loss is 21.64 ㎉/mole. We confirm that the electric conduction mechanism of PVDF thin film is dominated by ionic conduction by investigating the dependence of the leakage current of the thin film on the temperature and the electric field.