• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.1 no.1
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• pp.11-23
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• 2003

A study on the electrolytic dissolution of SUS-304 and Inconel-600 specimen was carried out in neutral salt electrolyte to evaluate the applicability of electrochemical decontamination process for recycle or self disposal with authorization of large amount of metallic wastes contaminated with uranium compounds generated by dismantling a retired uranium conversion plant in Korea. Although the best electrolytic dissolution performance for the specimens was observed in a Na2s04 electrolyte, a NaNO$_3$ neutral salt electrolyte, in which about 30% for SUS-304 and the same for Inconel-600 in the weight loss was shown in comparison with that in a Na$_2$SO$_4$ solution, was selected as an electrolyte for the electrochemical decontamination of metallic wastes with the consideration on the surface of system components contacted with nitric acid and the compatibility with lagoon wastes generated during the facility operation. The effects of current density, electrolytic dissolution time, and concentration of NaNO$_3$ on the electrolytic dissolution of the specimens were investigated. On the basis of the results obtained through the basic inactive experiments, electrochemical decontamination tests using the specimens contaminated with uranium compounds such as UO$_2$, AUC (ammonium uranyl carbonate) and ADU (ammonium diuranate) taken from an uranium conversion facility were performed in 1M NaNO$_3$ solution with the current density or In mA/$\textrm{cm}^2$. it was verified that the electrochemical decontamination of the metallic wastes contaminated uranium compounds was quite successful in a NaNO$_3$ neutral salt electrolyte by reducing $\alpha$ and $\beta$ radioactivities below the level of self disposal within 10 minutes regardless of the type of contaminants and the degree of contamination.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.4
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• pp.75-82
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• 2019

Flexible solar cells have attracted enormous attention in recent years due to their wide applications such as portable batteries, wearable devices, robotics, drones, and airplanes. In particular, the demands of the flexible silicon and compound semiconductor solar cells with high efficiency and high reliability keep increasing. In this study, we fabricated a flexible InGaP/GaAs double-junction solar module. Then, the effects of the wind speed and ambient temperature on the operating temperature of the solar cell were analyzed with the numerical simulation. The temperature distributions of the solar modules were analyzed for three different wind speeds of 0 m/s, 2.5 m/s, and 5 m/s, and two different ambient temperature conditions of 25℃ and 33℃. The flexibility of the flexible solar module was also evaluated with the bending tests and numerical bending simulation. When the wind speed was 0 m/s at 25 ℃, the maximum temperature of the solar cell was reached to be 149.7℃. When the wind speed was increased to 2.5 m/s, the temperature of the solar cell was reduced to 66.2℃. In case of the wind speed of 5 m/s, the temperature of the solar cell dropped sharply to 48.3℃. Ambient temperature also influenced the operating temperature of the solar cell. When the ambient temperature increased to 33℃ at 2.5 m/s, the temperature of the solar cell slightly increased to 74.2℃ indicating that the most important parameter affecting the temperature of the solar cell was heat dissipation due to wind speed. Since the maximum temperatures of the solar cell are lower than the glass transition temperatures of the materials used, the chances of thermal deformation and degradation of the module will be very low. The flexible solar module can be bent to a bending radius of 7 mm showing relatively good bending capability. Neutral plane analysis was also indicated that the flexibility of the solar module can be further improved by locating the solar cell in the neutral plane.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.5
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• pp.758-763
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• 2003

Amino acid transporters play an important role in supplying nutrients to normal and cancer cells for cell proliferation. System L is a major transport system responsible for the N $a^{＋}$-independent, large neutral amino acids including several essential amino acids. L-type amino acid transporter 1 (LAT1), an isoform of system L amino acid transporter, is highly expressed presumably to support their continuous growth and proliferation in malignant tumors. 2-Aminobicyclo- (2,2,1) -heptane-2-carboxylic acid (BCH) is a model compound for study of amino acid transporter as a system L selective inhibitor. In the present study, we examined whether BCH induced growth inhibition in KB human oral squamous carcinoma cell line or not. The uptake of L-［$^{14}$ C］leucine by KB cells is inhibited by BCH in a concentration dependent manner with a Ι $C_{50}$ value of 75.3$\pm$6.2 ${\mu}{\textrm}{m}$ and a $K_{i}$ value of 98.7$\pm$ 4.1 ${\mu}{\textrm}{m}$. The growth of KB cells is inhibited by BCH in time dependent manner and concentration dependent manner with a Ι $C_{50}$ value of 11.1 $\pm$0.8 mM. In the DNA of KB cells treated with the various concentrations and various periods of BCH, the characteristic ladders associated with DNA fragmentation were not observed. These results suggest that BCH inhibits the growth of KB oral epidermoid carcinoma cells through the inhibition of transport of neutral amino acids into cells without DNA break down. This phenomenon will be a new rationale for anti-cancer therapy.y.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.4
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• pp.202-209
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• 2002

The stochiometric mix of evaporating materials for the $CuInSe_2$single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CuInSe_2$compound crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $620^{\circ}C$ and $410^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CuInSe_2$single crystal thin films measured from Hall effect by van der Pauw method. From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the $CuInSe_2$single crystal thin film, we have found that the values of spin orbit splitting $\Delta$So and the crystal field splitting $\Delta$Cr. From the photoluminescence measurement on $CuInSe_2$single crystal thin film, we observed free exciton ($E_x$) existing only high quality crystal and neutral bound exciton ($A^{\circ}$, X) having very strong peak intensity. Then, the full-width-at-half-maximum (FWHM) and binding energy of neutral donor bound exciton were 7 meV and 5.9 meV, respectivity. By haynes rule, an activation energy of impurity was 59 meV.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.555-560
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• 2008

Amino acid transporters are essential for the growth and proliferation in all living cells. Among the amino acid transporters, the system L amino acid transporters are the major nutrient transport system responsible for the $Na^+$-independent transport of neutral amino acids including several essential amino acids. The L-type amino acid transporter 1 (LAT1), an isoform of system L amino acid transporter, is highly expressed in cancer cells to support their continuous growth and proliferation. 2-Aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH) is a model compound for the study of amino acid transporter as a system L selective inhibitor. We have examined the effect and mechanism of BCH on cell growth suppression in HEp2 human head and neck squamous cell carcinoma. The BCH inhibited the L-leucine transport in a concentration-dependent manner with a $IC_{50}$ value of $51.2{\pm}3.8{\mu}M$ in HEp2 cells. The growth of HEp2 cells was inhibited by BCH in the timeand concentration-dependent manners. The formation of DNA ladder was not observed with BCH treatment in the cells. Furthermore, the proteolytic processing of caspase-3 and caspase-7 in the cells were not detected by BCH treatment. These results suggest that the BCH inhibits the growth of HEp2 human head and neck squamous cell carcinoma through the intracellular depletion of neutral amino acids for cell growth without apoptotic processing.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.361-365
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• 1978

Physico-chemical characteristics of crude oil extracted from Korean Hazel nut were determined and its proximate composition was also analyzed. The proximate composition of Hazel nut was shown to be moisture 4.0%, crude protein 15.5%, crude fat 64%, nitrogen free extractive 11.7%, crude fiber 2.0% and crude ash 2.5%. The content of crude fat in Corylus sieboldiana was about 3% higher than in Corylus mandshurica.. Physico-chemical characteristics of crude oil found were: specific gravity, $0.916(15/15^{\circ}C)$; refractive index, $1.468(15^{\circ}C)$; saponification value, 184; iodine value, 94.5: acid value, 0.2; and unsaponifiable content, 0.25%. The lipid fractions in the crude oil obtained by silicic acid column chromatography were found to be composed of about 97% neutral lipids and about 3% compound lipids. Among the neutral lipids by TLC, triglycerides were 98% as the major components, free fatty acids and free strols were 0.5% and 1.3%, respectively. Esterified sterols were not found. The predominant fatty acids were oleic $(76{\sim}80%)$, linoleic (15%) and palmitic (5.0%), and the P/S ratio was $1.8{\sim}2.8$.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.80-86
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• 2002

Volatile compounds in three different kinds of crude vinegars obtained from oak (Quercus serrata), bamboo (phyllostachys) and pine (Pinus densiflora) species were analyzed by the solid-phase microextraction (SPME) method. A total of 264 peaks were detected on the chromatograms obtained from the polar (CBP 20) and the nonpolar (CBP 1) columns, which were used for analyzing the volatile compounds in these vinegars. The major volatile compounds identified by using the polar column were 2-butanone, acetic acid, guaiacol, phenol, cresols, 4-ethyl guaiacol, 4-ethyl phenol, and syringol. Using the nonpolar column, seven compounds could be identified: 1,2-dimethoxybenzyl alcohol, 1-hydroxy-2-butanone, 1-(2-furanyl)-1-propane, ethisolide, furfuryl acetate, 1,2-dimethoxybenzene, phenyl acetate. The volatile compounds were classified into five groups: phenols, neutral compounds, organic acids, esters and others. The phenols were the main component and comprised 49~65% of the volatile compounds of these vinegars. In the case of bamboo vinegar, the proportion of the phenols in the volatile compounds was lower than that of the two wood vinegars. However, the proportions of the neutral compounds and the organic acids were higher than those of the wood vinegars. Therefore, it seems that these differences of the proportions of the volatile compounds would make a certain difference of a smoke flavor between the bamboo vinegar and the wood vinegars.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.271-277
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• 2000

Transparent $TiO_2$ thin films were prepared by the sol-gel method from titanium alkoxide aqueous solution containing large quantities of water. To prepare the aqueous system sol, the chelate compound solution were prepared from each 1 mole of titanium(IV)iso-propoxide, acetylacetone and 8 moles of isopropyl-alcohol. And then the 50 moles aqueous solution with the 0.02~0.50 moles of HCI for sol stability and the 0.3 mole of polyethylene glycol for coating adhesion were precisely dropped on the chelate compound solution. $TiO_2$thin films were fabricated by dip coating, drying and heat treatment at $400^{\circ}C$ and their characteristics were investigated by XRD, SEM and UV-visible spectrometer, The neutral sol of composition with TTIP : AcAc : IPA : $H_2O$ : PEG : HCl = 1 : 1 : 8 : 50 : 0.3 : 0.15 (molar ratio) was maintained stable sol condition and without problem for coating more than 30 days. The anatase phase $TiO_2$thin film prepared from 30 times dipping, drying and heat treating showed the flat surface and the fine microstructure of fracture surface with about 2 $\mu\textrm{m}$ thickness. Transparency of these $TiO_2$thin film was 80 % in the visible region.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.122-129
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• 2002

In order to elucidate a responsible mechanism for the development of the odor characteristics of cooked desirable flavoring materials such as crab and shrimp, shore swimming crab flesh were extracted with various solvents and resulting extracts were evaluated organoleptically after cooking. As a result, $80\%$ aqueous methanol extract (AME) was found to produce a cooked desirable flavoring odor. After dialysis of AME, outer dialyzate was fractionated by ionexchange column chromatography, and each of the fraction obtained was subjected to cooking, fellowed by organoleptic evaluation. The outer dialyzate fraction, acidic and amphoteric fraction produced a cooked crab-like odor, On the basis of the composition of $80\%$ AME, an artificial crab extract was prepared with pure chemicals. The artificial crab extract thus obtained closely resembled $80\%$ AME in respect of the cooked odor. To elucidate the role of individual components, the artificial extracts from which certain component alone or as group was omitted were subjected to organoleptic evaluation after cooking. All of neutral, acidic, basic, and sulfur containing amino acids and quarternary base compounds were involved in the development of the cooked crab-like odor. The cooked odor of artificial extract without addition of ribose was lacking in the characteristics of cooked crab odor, and phosphorus compound accelerated the development of the cooked crab-like odor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1817-1826
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• 2014

This study investigated lipid profiles and antioxidant capacities of seven Korean rapeseed cultivars (Naehan, Tamla, Mokpo111, Yeongsan, Tammi, Hanla, and Mokpo68). The rapeseeds contained 29.3~33.2% of extracted lipid and major fatty acids were oleic, linoleic, and linolenic acids. The ratio of omega-6/omega-3 fatty acids was 2.20~3.68 with the highest in Hanla and lowest in Naehan. Glycolipid ranged from 0.21 g/100 g to 0.47 g/100 g. Phospholipid content was 0.55~1.15 g/100 g with the highest in Tammi and the lowest in Mokpo68, and the most common phospholipid was phosphatidylcholine. Tocopherol content was 9.45~15.11 mg/100 g in the order of ${\gamma}$ > ${\alpha}$ > ${\beta}$ > ${\delta}$-tocopherol, and Naehan contained the highest amount of tocopherols (P<0.05). Total phenol content (TPC) of rapeseed was 314.64~577.08 mg SAE/100 g. Tamla contained the highest TPC, and showed the highest antioxidant activity determined by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging capacity and ferric reducing antioxidant power.