• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.1074-1079
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• 1996

Physicochemical characteristics of pigment separated from cockle shell were studied. Pigment on the cockle shell was peeled with distilled water, and soaked in 4% TCA solution for 30 minutes and filtered. Filtrate was washed 3 times with distilled water and Iyophilized. Dried pigment was dissolved with 2N NaOH solution and preparative TLC with 2N NaOH : acetone(1 : 1). UV/vis spectrum of pigment separated from cockle shell and melanin as standard was same one peak at UV area and λ$_{max}$was 226nm. Dissolved property of pigment was same as that of melanin. Pigment was not ommochrome but like melanin, because it was insoluble in formic acid, whitening in $H_2O_2, $ and pattern of UV-spectrum was same as melanin. Pigment separated from cockle shell was stable at high temperatures. In thermal treatment at $70^{\circ}C, $ $80^{\circ}C, $ $90^{\circ}C$ and $100^{\circ}C$ for 8 hours, retention ratio of pigment separated from cockle shell were 95.0%, 93.3%, 90.8% and 87.6%, respectively.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.503-509
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• 2003

For the development of the anti-obesity natural drug, the inhibitor of adipocyte differentiation was screened from Korean traditional medicinal plants. Phellodendri Cortex was selected as a candidate of adipocyte differentiation inhibitor. An inhibitory compound PC-4 was purified from the methanol (MeOH) extract of Phellodendri Cortex using silica gel and ODS RP-18 column chromatography and HPLC. PC-4 was obtained as yellow powder; UV ${\lambda}_{max}$ (MeOH): 230, 260, 340 and 430 nm. The chemical structure of PC-4 was determined as an isoquionoline alkaloid, berberine, on the basis of various NMR experiments including $^1H-\;and\;^{13}C-NMR$. The PC-4 inhibited the differentiation of preadipocyte NIH-3T3 L1 cells at a concentration of $1\;{\mu}g/mL$.

• Analytical Science and Technology
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• v.11 no.2
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• pp.96-104
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• 1998

A photodiode array multichannel detector system for capillary electrophoresis was developed. The photodiode array detector for capillary electrophoresis (CE-PDA) has 1024 photodetectors and can analyze sample by measuring UV/VIS absorption spectrum in 275~675 nm wavelength range. The CE-PDA instrument can get a spectrum in 30 ms during sample separation and can be programmed by a PC to control various experimental conditions required for sample analysis. The performance of the multichannel CE-PDA instrument was tested using L-ascorbic acid and alizarin yellow GG mixture. The reproducibility test of the CE-PDA system showed 5.6% RSD.

• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.22-29
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• 1997

Ultraviolet weavelength (UV) of 366 nm produced clearer fluorescent dolor than that of 254 nm for the inspection of silkworm cocoons. Fluorescent color of silkworm cocoons varied in color, appears no relationship with the natural color under the normal light. Uniformity of fluorescent color was improved by selection of blue or yellow line from wild types. Blue and yellow, located at the opposite poles on the color solid and L*a*b* color system, confirmed as pure standard of fluorescent color in the silkworm races for commercial white cocoons. the cocoons with blue fluorescence occupied as high as 1.7 to 8.6 times than those with yellow in the Japanese silkworm races. Fluorescence of silkworm cocoon was not affected by forced flow dry at 70$^{\circ}C$ for 6 hrs. While the Japanese races revealed no sexual difference in fluorescent color, sex-dependence of the color was common in the Chinese races for commercial white cocoon. The fluorescence of cocoon shell of Chinese races showed clear separation of blue of median color. Silkworm strain of Dc20 and Fc24 were sexualy segregated 98.8${\pm}$1.20%, 99.0${\pm}$1.00% by cocoon fluorescence, as that of 99.3${\pm}$0.44% by typical larval marking of sex-limited inheritance. Specific expression of cocoon fluorescence, applicable to breeding of simple discrimination of sex for Chinese races, inspected thoroughly on the surface and inner layer of cocoon shell.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.2
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• pp.145-151
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• 2001

In this study, blue light emiting, soluble PPV copolymers were synthesized by Witting reaction and characterized. ITO/copolymer/Ca and ITO/copolymer/A1 structured light emitting diodes(LED) were fabricated and their I-V characteristics were examined. Copolymers showed $\pi$-$\pi$ transition in UV-Vis./NIR spectra. The PL and abosorption spectrum showed the symmetric vibration modes with mirror images which means that copolymers are highly aligned. By introducing aliphatic hydrocarbon group on polymer main chain, the solubility of copolymers was improved and no significant effects of substituent were observed. The band offset of copolymers are well suited as light emitting material for LED application than monomer or oligomer does. THe band offset of copolymers is ∼3eV in PL spectrum and the threshold voltages of ITO/copolymer/Ca and ITO/copolymer/Al structured LED 3V, 12V respectively. In the case of ITO/copolymer/Ca LED, it is believed that the amount of electrons and holes is well balanced and the recombination of opposite charges occurs easily because the work functions of Ca and Al electrodes are 2.9 and 4.3eV respectively and the difference in barrier height between polymer and electrode was small.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.1
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• pp.42-47
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• 2017

In this study, the physical and optical properties of $ZnS:Mn^{2+}$ Quantum Dot prepared by wet-process condition with Mn/Zn ratio was valuated. The powder characteristics and optical behavior were investigated through XRD, TEM and Photo spectrometer exicted by various UV light source. We found the main peak of ZnS (111) was shifted by 0.8 degree to low angle position with increasing stirring energy from 200 RPM to 600 RPM, which is thought to be the increase of lattice defects during wet process. The photo luminescence at 600 RPM shows also higher blue intensity which is well correlated with XRD results. With increasing Mn/Zn ratio, the PL intensity become higher and shifed by 8.5nm to right side, by the increment of substitutional $Mn^{2+}$ ions.

• Journal of Ginseng Research
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• v.25 no.2
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• pp.82-88
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• 2001

This study was carried out to investigate a point of difference between normal and inferior Korean red ginseng (Naeback red ginseng = red ginseng with white part of clear boundary in phloem and/or xylem of ginseng body, saengnaeback red ginseng red ginseng with white part of indistinct boundary). White part with clear or indistinct boundary in center of ginseng body was observed in inferior red ginseng (naeback and saengnaeback red ginseng), and the differences in the internal color intensity was also found with naked eye. In hunter color values of normal and inferior parts of red ginseng in accordance with particle size, L value was increased with a diminishment in particle size, while a and b value were decreased. Absorbance at visible spectrum did not differ from water and 70% ethanol extract from normal and inferior parts of red ginseng, but absorbance in UV spectrum of extract from naeback part showed higher than those of normal and saengnaeback part. In comparison of intrastructure by electron microscope, the horizontal and vertical section of cortex and pith layer from normal part showed the very dense state, but small holes were found in naeback part of red ginseng by naked eye and electron microscope. The specific surface area of normal, naeback and saengnaeback part appeared 3.02, 3.33 and 6.55 ㎡/g, respectively. From above results, we consider saengnaeback red ginseng is red ginseng in the intermediate process which normal red ginseng changes to naeback red ginseng.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1779-1783
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• 2004

In the present study, we carried out comparative research on the anthraquinones Raman spectrum and on the anthraquinones derivative 1,4-diamino-anthraquinone focusing on change in its intermediate in terms of pH and change in the substituent. WE use the SERS method and employ a silver sol prepared by Creighton et al.'s method. From the analysis of the UV spectrum of the mixture solution of 1,4-diamino-anthraquinone and silver sol, we could see that the 1,4-diamino-anthraquinone physically adsorbs silver sol. In terms of the adsorbing orientation, the adsorption of the nitrogen atom in the amino group is perpendicular to the surface of silver sol according to the surface selection rule. From the structure of the 1,4-diamino-anthraquinone intermediate according to the change of pH, we could see that the C=O bond is strengthened in the acidic state and weakened in the neutral and the alkaline state because of the resonance effect of the amines.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.52-55
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• 1996

The spectra of whole blood EDTA samples from two people were generated using a CARY 5E (UV-VIS-NIR) spectrophotometer from 400 to 1000nm which contain visible and NIR region. Only the data between 400 and 800nm were used to analyze the components of blood. Using the same spectrophotometer, the spectra of Water, normal saline, plasma were generated These spectra were subtracted from each blood sample, and then the first derivative of each of the subtracted data was taken to minimize baseline variations and indicated the wavelength-shift of peak and valley. Normalization and division between two blood samples were used to correlate the quantity ratio of specific components with feature of spectra. Samples were controlled at $30^{\circ}C,\;37^{\circ}C$, ambient temperature.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.7
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• pp.650-657
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• 2007

This paper had mentioned about CCP light source application for increasing the efficiency of Xe lamp the mercury-free lamp. In order to increase the efficiency of Xe EEFL, we designed and manufactured the lamp used by mixture gas of Xe, Ne and He. Also, we have analyzed the electrical and optical properties with the firing voltage, sustain voltage, paschen's curve, wall charge, and capacitance. As a result, the firing voltage decreased by increasing the ration of mixture gas. and, It is owing to include the gas with high ionization energy. The firing voltage decreased in condition happening the penning effect, Because the ion of metastable state created from penning effect, Which can encourage the ionization phenomena. Also, the wavelength of 467.12 is increase. because of the energy transition in the wavelength of 147 nm. therefore, we can know about the affection of phosphor with UV emission properties. Through an experiment, Xe 100 % and Xe 75 % confirmed same spectrum properties by each mixture gas ratio. In the case of Xe 50 %, spectrum properties appeared Xe discharge and Ne-He discharge. That analyzed an electrical and optical properties. Therefore, confirmed that is excellent because properties of firing voltage, wall charge, capacitance in Xe 50 %, Ne : He = 9 : 1. We offered parameter in inverter manufacture and lamp manufacture by electrical and optical properties.