• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.4
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• pp.777-790
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• 2001

Theoretical analyses have been tried to design high power and stable operating SLD at 1.55${\mu}{\textrm}{m}$ wavelength range which is the lowest absorption wavelength in optical fiber. The materials of active layer and SCH layer were chosen as conventional In1-xGaxAsyPl-y quaternary composition systems. From the transverse mode and the lateral mode analyses of waveguide, the optical power distributions and the optical confinement factor have been studied for single-mode high power operation. According to these analyses, it was calculated the composition and the thickness of SCH layer to obtain the maximum optical confinement factor. In order to obtain low values of the reflectivity, we used the window region and the lateral tilted angle between tile active region and window region. And the reflectivity of SLD was calculated with the gaussian beam approximation and mode analysis. From these researches, it was confirmed for several results to fabricate the efficient and stable SLD. In case of using $1.3\mum$, InGaAsP SCH layer, the layer thickness was obtained $0.08\mum$, to get the maximum optical confinement factor. Using $0.2\mum$, active layer thickness and $0.08\mum$, SCH layer thickness, the window region length is about $100\mum$ without An coating, $10\mum$ in 1% AR coating to obtain about 10-4 reflectivity. When the tilted angle is about $10~15^{\circ}$, the reflectivity is about 10-3. From these results, if the window region length and tilted angle were controlled appropriately in given device structure, it was confirmed that it is possible to fabricate the stable SLD without AR coating analytically.

• Korean Journal of Remote Sensing
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• v.14 no.4
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• pp.353-365
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• 1998

Light absorption coefficient per unit mass of particles, i.e., specific absorption coefficient, is important as one of the main parameters in developing algorithms for ocean color remote sensing. Specific absorption coefficient of chlorophyll ($a^*_{ph}$) and suspended sediment ($a^*_{ss}$) were analyzed with a spectrophotometer using the "wet filter technique" and "Kishino method" for the seawater collected in the Yellow and Mediterranean Sea. An improved data-recovery method for the filter technique was also developed using spectrum slopes. This method recovered the baselines of spectrum that were often altered in the original methods. High $a^*_{ph}({lambda})$ values in the oligotrophic Mediterranean Sea and low values in the Yellow Sea were observed, ranging 0.01 to 0.12 $m^2$/mg at the chlorophyll maximum absorption wavelength of 440 nm. The empirical relationship between $a^*_{ph}$(440nm) and chlorophyll concentrations () was found to fit a power function ($a^*_{ph}$=0.039 $^{-0.369}$), which was similar to Bricaud et al. (1995). Absorption specific coefficients for suspended sediment ($a^*_{ss}$) did not show any relationship with concentrations of suspended sediment. However, an average value of $a^*_{ss}$ ranging 0.005 - 0.08 $m^2$/g at 440nm, was comparable to the specific absorption coefficient of soil (loess) measured by Ahn (1990). The morepronounced variability of $a^*_{ss}$ than $a^*_{ph}$ was determined from the variable mixing ratio values between particulate organic matter and mineral. It can also be explained by a wide size-distribution range for SS which were determined by their specific gravity, bottom state, depth and agitation of water mass by wind in the sea surface.

• Journal of Conservation Science
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• v.31 no.3
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• pp.299-308
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• 2015

Aim of this study is to identify dyestuff of the Dallryeong(official's robe in Joseon Dynasty, 16th century) excavated from Yuryang-dong, Cheonan, in 1996. For this purpose, extracted dyestuffs from Dallryeong fabric and from natural dyestuffs for red color(safflower, Sapanwood, Madder) which are presumed to have been used in the Dallryeong, are analyzed and compared by high performance liquid chromatography(HPLC). As a result, HPLC chromatogram of extracts of the Dallryeong's dyestuff and safflower are showed a peak at 17.5 minutes. The UV/Vis spectra of the samples are showed the maximum absorption wavelength at 519nm. This result is identical with the analysis of the previous studies on red dyestuff of safflower. In addition, the analysis of Mass Spectrometry(MS) showed the identical result of the peak with m/z 910. Following these results, excavated pink Dallryeong were considered to have been dyed with safflower.

• Applied Chemistry for Engineering
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• v.2 no.1
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• pp.70-76
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• 1991

Water soluble poly(sulfonated styrene-co-acrylic acid) was polymerized with sulfonated styrene and acrylic acid in the presence of silver sulfate at $99^{\circ}C$ for 4 hrs. The complex formation of poly(sulfonated styrene-co-acrylic acid) with Cu(II) was carried out. The maximum absorption wavelength of the poly(sulfonated styrene-co-acrylic)-Cu(II) system at different pH values was observed at 274 nm and 295 nm. The reduced viscosity of the poly(sulfonated styrene-co-acrylic acid)-Cu(II) complex were measured in the various pH ranges. The formation constants and stability constants of poly(sulfonated styrene-co-acrylic acid)-Cu(II) complex were calculated from Bjerrum method. The changes of enthalpy, free energy and entropy in the above reaction were determined by Ringbom method.

• Fashion & Textile Research Journal
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• v.11 no.6
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• pp.953-960
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• 2009

The natural dyeing of fabrics with myrobalan extract was investigated. After dyeing of silk, cotton and rayon with myrobalan extract, the dyeability of myrobalan extract was evaluated with the conditions of concentration, temperature, time, repeat-numbers, pH, mordants variables, the changes of dyeability and surface colors by methods of mordanting and color fastness. The wavelength of maximum absorption of the colored solution from myrobalan extract appeared at 272 nm. Therefore, the substance of myrobalan extract was verified as tannin dyes. The optimum dyeing of fabrics was carried out at 30%(o.w.f) dye concentration. Silk fabrics dyed with myrobalan extract showed the highest K/S value at the temperature of $80^{\circ}C$ when it was dyed for seventy minutes, while cotton and rayon fabrics showed the highest K/S value at the temperature of $90^{\circ}C$ when they were dyed for seventy minutes and thirty minutes, respectively. Dyeing operation was carried out in acidic dyebath of pH 3. The K/S value of silk fabric was higher in pre-mordant stage than in post-mordant, while the K/S values of cotton and rayon fabrics were higher in post-mordant stage. The surface colors of dyed fabrics were different according to used mordants: Al and Cu mordanted fabrics were dyed in yellowish colors, while Fe mordanted fabric was dyed in khaki-black color. Light-fastness of the color fastness was improved in Fe-mordant. Washing-fastness was relatively good, and dry cleaning-fastness of dyed fabrics was excellent.

• Journal of Fashion Business
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• v.11 no.1
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• pp.136-148
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• 2007

African marigold is a common plant easily available in many flower beds. It has been reported as a practical and prospective resource of dyes since the dyes can be extracted from their bodies as well as petals. In this research, cotton and ramie fabrics which are made from natural cellulose were dyed using the extract of the African Marigold which is a variety of marigold. Dyeing tests were carried out under different pH of the dye solution and mordants. Dyeability was evaluated by examining and measuring surface color, K/S value, and the changes in the maximum absorption wavelength. The probability of improving dyeability was investigated by pre-mordanting with pre-treated chitosan. For the dyeing with marigold extract, the color tone did not differ by pre-mordanting and non-mordanting. Reaction with post-mordanting was excellent, which was colored in various yellow series. The best dyeability was achieved in dye solution of pH 6.5-7.0 which is not conditioned. The largest K/S value and color difference were obtained in tin mordanting. The dye uptake was greatly increased in chitosan pre-treated mordanting compared with the post-mordanting without chitosan pre-treatment. Due to its high heat resistance, African Marigold extract is easy for dye extraction and dyeing, and its dyeability is excellent for natural cellulose fibers. Also, colorfastness was proved to be practically usable.

• Analytical Science and Technology
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• v.9 no.2
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• pp.139-144
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• 1996

The spectrophotometric determination method of scandium with eriochrome cyanine R(ECR) and the composition ratio of the complex were investigated in the presence of surfactants. The absorbance increase and red shift of maximum adsorption wavelength of Sc(III)-ECR complex were observed in cetyltrimethylammonium bromide (CTMAB), but those changes were not observed in the sodium dodecyl sulfate(SDS) and Triton X-100. A volume of 5ml of $1{\times}10^{-3}M$ ECR and 10ml of $2{\times}10^{-4}M$ CTMAB are necessary for the determination of $1{\times}10^{-7}{\sim}3.0{\times}10^{-6}M$ Sc(III) at pH 6.5. The apparent molar absorption coefficient of the Sc(III)-ECR-CTMAB, temary complex at 610nm is $5.6{\times}10^5mol^{-1}cm^{-1}L$ and its detection limit is $1.0{\times}10^{-7}M$. The binary complex composition of Sc(III)-ECR is 1:2 and the ternary complex composition of Sc(III)-ECR-CTMAB is 1:3:1.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.248-251
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• 1982

Commassie blue G250 produced metachromatic effect with some solvents. The absorptivity and molar absorptivity of the dye in ethanol were 82.4 and $70.4{\times}10^3$ at maximum absorption wavelength 610nm, respectively. The dye had a red from$({\lambda}_m=465nm)$ in ethanol-phosphoric acid-water solution and converted to a blue form$({\lambda}_m=590nm)$ after binding to protein. Absorbance at 590nm gave linear responses with respect to protein contents. The dye-binding capacities of proteins varied considerably with the content and source of proteins. Under the experimental condition the dye-binding capacities of bovine serum albumin, cytochrome C and ${\gamma}-globulin$ were 110, 103, and $88{\mu}g$ commassie blue G250 bound per $100{\mu}g$ protein, respectively.

• Korean Journal of Optics and Photonics
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• v.28 no.6
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• pp.361-365
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• 2017

In this paper, we demonstrate a facile fabrication technique for a periodically aligned metal nanoparticle array, for a narrow-band plasmonic absorber. The metal nanoparticles are fabricated by e-beam evaporation and heat treatment processes on top of a periodic aluminum groove template. The plasmonic absorber is constructed with the transferred metal nanoparticle array, sputtered 33-nm-thick $Al_2O_3$, and 200-nm-thick metal reflector layers on silicon substrate. 46-nm-diameter and 76-nm-lattice metal-nanoparticle-array-based plasmonic absorber has performed as a narrow-band absorber with a central wavelength of 572 nm and full width at half maximum (FWHM) of 109.9 nm.

• Fisheries and Aquatic Sciences
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• v.3 no.3_4
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• pp.195-199
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• 2000

Tyrosinase inhibitory activities of 14 kinds of seaweed, Ecklonia stolonifera, Ecklonia cava, Undaria pinnatiflda, Laminaria japonica, Sargassum fulvellum, Sargassum miyabei, Sargassum thunbergii, Porphyra yezoensis, Gracilaria verrucosa, Carpopeltis affinis, Pachymeniopsis elliptica, Gelidium amansii, Codium fragile and Ulva pertusa were determined using commercially available mushroom tyrosinase in an in vitro assay system. The $1\%$ (w/v) methanol extract from E. stolonifera showed the highest tyrosinase inhibitory activity of $79.0\%$, electron donating activity of $79.0\%$ and total phenol content of 3.75 mg/100g. Ethyl acetate-methanol-water (7 : 2 : 0.2, v/v) fraction $(0.5\%,\;w/v)$ isolated from the methanol extract showed tyrosinase inhibitory activity of $75.9 \%$, electron donating activity of $88.1 \%$ and total phenol content of 4.38 mg/100g. Tyrosinase inhibitory activity was closely associated with total phenol content (R = 0.99) and electron donating activity (R=0.99). Maximum absorption wavelength of the fraction was 218nm and that of phenolic compounds showed about a range from 210 to 220nm. The inhibition mode of the fraction was noncompetitive inhibition.