• Korean Journal of Food Science and Technology
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• v.3 no.2
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• pp.101-104
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• 1971

The dye-binding method based on the reaction of acidic orange-G dye with basic groups of protein molecule was investigated to observe its applicability to the determination of protein, basic amino acid and lysine contents in brown rice of several high-protein rice lines. The protein content of rice samples ranged from 7.91 to 10.53% and from 8.93 to 11.96% in terms of wet and dry bases, respectively. The correlation between dye-binding absorbance and protein content in terms of both dry and wet bases was highly significant; their correlation coefficients being $-0.955^{**}\;and\;-0.975^{**}$, respectively. The correlation of dye-binding absorbance lysine and basic amino acids were highly significant and their correlation coefficients were similar. Dye-binding absorbance-lysine showed a lower correlation than dye-binding absorbance-protein but a higher correlation than protein-lysine.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.145-148
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• 2000

In contrast to the $\pi$ -conjugated polymers which typically absorb light only in the visible spectral region, the $\sigma$-conjugated polymers can be used as efficient material absorbing light in the UV region. In this work, the electronic and optical properties of I$_2$-doped $\sigma$ -conjugated poly (methyl-phenylsilylene) (PMPSi) polymer were investigated. DC conductivity up to 1.2$\times$10$^{-4}$ S/cm was obtained by I$_2$-doping. In UV/Vis absorbance spectrum, a new peak was observed near 370 nm, which was explained by polaron model. The photoluminescence (PL) intensity decreased with increasing degree of I$_2$-doping, and the Infrared (IR) spectrum analysis revealed that the dopants are not directly coupled to the polymer, but effect motions of the methyl and phenyl groups.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1196-1198
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• 1995

In this paper, stability improvement of fragile LB films was attempted by monolayers at the air-water interface and crosslinking of the resulting LB films. The spreading polymers were synthesized by radical copolymerization of monoalkyl with oligoethyleneglycol methyl ether, and poly(allylamine) was employed as the subphase polymer. The monolayer properties have been studied by the surface pressure-area($\pi$-A) isotherms. Interaction between polymers and metal ions at the air-water interface and in their LB films were investigated. From the FT-IR(Reflection and Transmission) spectra, the formation of carboxylate ions and the relative orientation of the side chains could be confined. The monolayers were transferable on various substrates, and the resulting LB films were characterized by SEM and VIS-UV absorbance.

• Journal of Environmental Science International
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• v.22 no.8
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• pp.999-1007
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• 2013

Electrochemical degradation of phenol was evaluated at DSA (dimensionally stable anode), JP202 (Ru, 25%; Ir, 25%; other, 50%) electrode for being a treatment method in non-biodegradable organic compounds such as phenol. Experiments were conducted to examine the effects of applied current (1.0~4.0 A), electrolyte type (NaCl, KCl, $Na_2SO_4$, $H_2SO_4$) and concentration (0.5~3.0 g/L), initial phenol concentration (12.5~100.0 mg/L) on phenol degradation and $UV_{254}$ absorbance as indirect indicator of by-product degraded phenol. It was found that phenol concentration decreased from around 50 mg/L to zero after 10 min of electrolysis with 2.5 g/L NaCl as supporting electrolyte at the current of 3.5 A. Although phenol could be completely electrochemical degraded by JP202 anode, the degradation of phenol COD was required oxidation time over 60 min due to the generation of by-products. $UV_{254}$ absorbance can see the impact of as an indirect indicator of the creation and destruction of by-product. The initial removal rate of phenol is 5.63 times faster than the initial COD removal rate.

• Journal of Microbiology and Biotechnology
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• v.20 no.11
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• pp.1513-1520
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• 2010

A bacterium capable of producing melanin pigment in the presence of L-tyrosine was isolated from a crop field soil sample and identified as Klebsiella sp. GSK based on morphological, biochemical, and 16S rDNA sequencing. The polymerization of this pigment occurs outside the cell wall, which has a granular structure as melanin ghosts. Chemical characterization of the pigment particles showed then to be acid resistant, alkali soluble, and insoluble in most of the organic solvents and water. The pigment got bleached when subjected to the action of oxidants as well as reductants. This pigment was precipitated with $FeCl_3$, ammoniacal silver nitrate, and potassium ferricynide. The pigment showed high absorbance in the UV region and decreased absorbance when shifted towards the visible region. The melanin pigment was further charecterized by FT-IR and EPR spectroscopies. A key enzyme, 4-hydroxyphenylacetic acid hydroxylase, that catalyzes the formation of melanin pigment by hydroxylation of L-tyrosine was detected in this bacterium. Inhibition studies with specific inhibitors, kojic acid and KCN, proved that melanin is synthesized by the DOPA-melanin pathway.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.392-396
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• 2014

New organic-inorganic composite of 2,4-dihydroxybenzophenone (BP-1) encapsulation into dodecylbenzenesulfonate (DBS) modified layered double hydroxide (LDH) was successfully prepared. The surface, structural, thermal and absorption properties of the BP-1/DBS-LDH nanohybrid was characterized by BET analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TG) and diffuse reflectance UV-Vis absorbance spectra (DRUV-vis). The interlayer configuration of composite and the adsorption mechanism of BP-1 on MgAl-DBS-LDH were discussed. It was suspected that DBS anions located in the form of monolayer arrangement with a $75^{\circ}$ anti parallel angle between dodecylbenzenesulfonate chain axis. The diffuse reflectance UV-Vis absorbance results revealed that the UV absorbing wavelength of BP-1/DBS-LDH evidently extends to about 400 nm, which shows that the BP-1/DBS-LDH has the potential application as a UV absorber.

• Journal of Environmental Health Sciences
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• v.1 no.1
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• pp.21-27
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• 1974

This work was carried out to investigate the chemical properties of the chelate compounds which were produced with 2-methoxy-5-nitrophenol(MNG) and metal salt such as copper nitrate and manganese nitrate. And obtained results were as in the followings. 1) The binding ratio of the chelate compounds formation were determined by using the molar ratio concentration method and their chemical structures were identified by IR-spectrum. 2) In the absorbance measuring, 2-methoxy-5-nitrophenol coordinated with manganese and copper showed the maximum absorbance at $430 m\mu$ and $410 m\mu$ respectively. 3) The binding ratio of chelated compounds were measured by molar ratio method and continuous variation method with spectrophotometer, which was identified as 1:2. 4) The conditional formation constant(log Kn value) of manganese and copper chelate compounds were 6.70, 6.75, respectively according to the equation of $log\frac{A-AM\circ n MNG}{AMm MNG-A}=n log (M\circ)+log Kn$ 5) The dissociations degree of manganese and copper chelate compound were $2, 300{\times} 10^{-7}$, $2, 346{\times} 10^{-7}$ respectively according to the molar calculation method.

• Journal of the Korean Society of Costume
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• v.14
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• pp.133-144
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• 1990

The purpose of this study is to investigate the absorbance of the Shikonin, one of the major purple pigments, and the stability against the effect of light, $O_2$, and temperature. The effect of mordant and mordanting condition to color and color-fastness is compared and analysed through the color-fastness-test, color-difference value-test, and IR-test. The results were as follows; 1. The absorbance of Shikonin was examinated through 6 kinds of solutions and distilled water. Shikonin was absorbed by solutions rather easily than distilled water. 2. The light effect to Shikonin indicated that the solution with the light was more stable than that without it. 3. The effect of $O_2$ to Shikonin showed that the solution with the $O_2$ was more stable that without it $O_2$. 4. Shikonin -methyl alcohol solution was stable in $25^{\circ}C$. It was unstable in $60^{\circ}C$ and $100^{\circ}C$ with lowered absorbance and changed colors. 5. Color-fastness test to silk and cotton indicated washing color-fastness and perspiration color-fastness was more than 3 grade. But the light color-fastness and crocking color-fastness was low. 6. The comparison between non -colored sample and colored-sample showed the latter was better in fastness. 7. Mordant as $Alk(SO_4)_2{\cdot}24H_2O$ and $AlCl_3{\cdot}6H_2O$ was better than anything else in fastness. 8. Color-difference value-test indicated that the mordant which had the jade green color, the original purple pigment color, was the best in use. 9. The best way to extract the original purple pigment color was in $25^{\circ}C$, because extracted dyeing solution by Soxhlet had the bluish color.

• International Journal of Oral Biology
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• v.46 no.3
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• pp.105-110
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• 2021

The physicochemical properties of crystalline titanium dioxide nanoparticles (TiO₂ NPs) were investigated by comparing amorphous (amTiO₂), anatase (aTiO₂), metaphase of anatase-rutile (arTiO₂), and rutile (rTiO₂) NPs, which were prepared at various calcination temperatures (100℃, 400℃, 600℃, and 900℃). X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses confirmed that the phase-transformed TiO₂ had the characteristic features of crystallinity and average size. The surface chemical properties of the crystalline phases were different in the spectral analysis. As anatase transformed to the rutile phase, the band of the hydroxyl group at 3,600-3,100 cm^-1 decreased gradually, as assessed using Fourier transform infrared spectroscopy (FT-IR). For ultraviolet-visible (UV-Vis) spectra, the maximum absorbance of anatase TiO₂ NPs at 309 nm was blue-shifted to 290 nm at the rutile phase with reduced absorbance. Under the electric field of capillary electrophoresis (CE), TiO₂ NPs in anatase migrated and detected as a broaden peak, whereas the rutile NPs did not. In addition, anatase showed the highest photocatalytic activity in an UV-irradiated dye degradation assay in the following order: aTiO₂ > arTiO₂ > rTiO₂. Overall, the phases of TiO₂ NPs showed characteristic physicochemical properties regarding size, surface chemical properties, UV absorbance, CE migration, and photocatalytic activity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.1
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• pp.55-59
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• 1999

The Rapid Expansion of Supercritical fluid Solutions (RESS) process was applied to particles coating. Microcapsules prepared by spray drying were used as the core particles, and two kinds of paraffin were used as the coating materials. Supercritical $CO_{2}$ solutions of paraffin were expanded through the short nozzle into the bed that was fluidized by air. Extraction temperature and pressure were varied at $50~120^{\circ}C$, $150~200\;kg/\textrm{cm}^2$, respectively. The thickness of theoritical coating layer ws measured, and precipitate coating layer on surface was analyzed by using SEM, FT-IR. The release behaviors of $Mg^{2+}$ ions were inspected by atomic absorbance spectrophtometer.