• Food Science and Preservation
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• v.21 no.3
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• pp.421-426
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• 2014

In this study, the antioxidant and pancreatic lipase inhibitory activities of aqueous methanolic (70% methanol) extract from the roots of Anemarrhena asphodeloides were investigated. The extracts of four solvent fractions (the n-hexane layer, EtOAc layer, n-BuOH layer, and $H_2O$ layer) of the 70% methanol extract were also investigated. Furthermore, the total phenolic content was quantified using a spectrophotometric method. All the tested samples showed dose-dependent radical scavenging and pancreatic lipase inhibitory activities. In particular, the pancreatic lipase inhibitory activity of the ethyl acetate soluble portion (the EtOAc layer) from the rhizomes of the A. asphodeloides was higher than that of the other solvent-soluble portions. The antioxidant property of the extracts was evaluated using radical scavenging assays with DPPH and $ABTS^+$ radicals. 1000 mg/ml of the n-BuOH layer extract showed 91.2% DPPH radical scavenging activity. The EtOAc layer extract and the n-BuOH layer extract showed $IC_{50}=20.5{\pm}1.7mg/ml$ and $IC_{50}=50.5{\pm}0.7mg/ml$ $ABTS^+$ radical scavenging activities, respectively. The anti-obesity efficacy of the A. asphodeloides extract was tested via porcine pancreatic lipase assay. A pancreatic lipase inhibitory activity ($IC_{50}$) of $31.3{\pm}0.1mg/ml$ was obtained from the EtOAc layer extract. These results suggest that A. asphodeloides can be considered a new potential source of natural antioxidant and anti-obesity agents.

• Economic and Environmental Geology
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• v.53 no.3
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• pp.297-306
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• 2020

The red mud generated from bauxite during the Bayer alumina production process has been regarded as an industrial waste due to the high alkaline property and high content of Na. Despite of its environmental problem, various studies for recovery of the valuable resources from red mud has been also carried out because of high content (25.7 wt.% as Fe₂O₃ in this study) of iron in red mud. In order to recover the iron resource in the red mud, microwave heating experiments were performed with adding of activated carbon and elemental sulfur to the red mud. Through the microwave heating the powdered red mud mixtures converted to porous and vitrified solid aggregates. The vitrified aggregates produced by microwave heating are composed of goethite, zero valent iron (Fe⁰), pyrrhotite and pyrite. And then, the microwave heating samples were dissolved in the aqua regia solution, and Fe precipitates were obtained as a Fe-chlorides by adding of NaCl salt in the aqua regia solution. The Fe recovery rates in the Fe-chloride precipitates showed differences depending on the experimental mixture conditions, and Fe grades of the end products are 49.0 wt.%, 58.0 wt.% and 59.5 wt.% under mixture conditions of red mud, red mud + activated carbon, and red mud + activated carbon + elemental S, respectively. The Fe content of 56.0 wt.% is generally known as the grade value of Fe in a iron ore for iron production, and the Fe grades of microwave heating samples with adding activated carbon and elemental S in this study are higher than the grade value of 56.0 wt.%.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.409-417
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• 2014

Since the oil price has been significantly jumped for recent some years, the diesel engine of the merchant ship has been mainly used the heavy oil of low quality. Thus, it has been often exposed to severely corrosive environment more and more because temperature of the exhaust gas in a combustion chamber is getting higher and higher with increasing of using the heavy oil of low quality. As a result, wear and corrosion of most parts surrounded with combustion chamber is more serious compared to the other parts of the engine. Therefore, an optimum weldment for these parts is very important to prolong their lifetime in a economical point of view. In this study, four types of filler metals such as Inconel 625, 718, 1.25Cr-0.5Mo and 0.5Mo were welded with SMAW and GTAW methods in the forged steel which would be generally used with piston crown material. And the corrosion properties of weld metal, heat affected zone and base metal were investigated using electrochemical methods such as measurement of corrosion potential, anodic polarization curves, cyclic voltammogram and impedance etc. in 35% H2SO4 solution. The weld metal and base metal exhibited the best and worst corrosion resistance in all cases of filler metals. In particular, the weld metal welded with filler metals of Inconel 718 revealed the best corrosion resistance among the filler metals, and Inconel 625 followed the Inconel 718. Hardness relatively indicated higher value in the weld metal compared to the base metal. Furthermore, Inconel 625 and 718 indicated higher values of hardness compared to 1.25cr-0.5Mo and 0,5Mo filler metals in the weld metal.

• Korean Journal of Materials Research
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• v.24 no.12
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• pp.671-676
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• 2014

It is known that bones get damaged by accidents and aging. Since the discovery of Bioglass, various kinds of ceramics have been also found to bond to living bone; some of these ceramics are already being clinically used as bone-repairing materials. In the present study, antibacterial calcium silicate gel ($Ag-30CaO{\cdot}70SiO_2$ gel) was prepared by sol-gel method in order to control the microstructure, which is related to the dissolution rate and induction period of apatite formation in body environment. In addition, biological $Ag-30CaO{\cdot}70SiO_2$ is tested. This was done to impart antimicrobial activity to the $30CaO{\cdot}70SiO_2$. Ag ion was added during sol-gel synthesis to replace the $H_2O$ added during the making of the $30CaO{\cdot}70SiO_2$ gel, which has silver solutions of various concentration. After the sol-gel process, 1N-$HNO_3$ solution was used to wash the gel when synthesizing the gel, in order to maintain the porous structure and remove PEG, water soluble polymers. Then, the apatite forming ability of the sol-gel derived CaO-$SiO_2$ gels was investigated using simulated body fluid (SBF), which had almost the same ion concentration as that of human blood plasma. The gels were analyzed by FT-IR spectroscopy, SEM observation, XRD, and fluorescent microscopy. The apatite was successfully created even after washing the gel; apatite is present in an amorphous state, and was found to affect the concentration of the Ag ion in cells in MC3T3 live & dead assay results. From these results, it is suggested that a good material that can be used to repair defects of nature bone is $Ag-30CaO{\cdot}70SiO_2$ gel.

• The Korean Journal of Pharmacology
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• v.18 no.1
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• pp.65-72
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• 1982

It has been known that retinoids are intrinsically of critical importance for control of premalignant epithelial cell differentiation. In the absence of retinoids, normal cellular differentiation and growth does not occur in epithelia such as those of trachea and bronchi. Furthermore, it was also reported that retinoid deficiency enhanced susceptibility to chemical carcinogenesis in the respiratory system, in the bladder, and in the colon of the experimental animal. In 1974, Bollag examined the effects of synthetic retinoids in prevention of development of cancer and demonstrated synthetic retinoids to have more favorable therapeutic index than retinoic acid for causing regression of skin papilloma in mice. Therefore, it was assumed that this anticarcinogenic effect of vitamin A derivatives could be due to modification of the metabolism of the carcinogenic polycyclic hydrocarbon, which must first be activated to exert their effect. Hill and Shih reported that vitamin A compounds and analogs had inhibitory effect on drug metabolizing enzyme from liver and lung tissue of mouse and hamster. Lucy suggested that the chemoprevention effect of vitamin A derivatives is due to reaction with molecular oxygen, and it is possible that inhibition of hydroxybenzpyrene formation is a result of this property. On the other hand, butylated hydroxytoluene which is a potent antioxidant strongly inhibited the formation of mammary tumor induced by dimethylbenranthracene. Also, it was observed that this antioxidant inhibited cancer induction in rats by N-2-fluo-renylacetamide. The purpose of this experiment was to investigate the effect of vitamin A derivatives such as retinoic acid and retinoid on drug-metabolizing enzyme and to determine whether riboflavin tetrabutylate or vitamin E could prevent of modify any changes induced by vitamin A delivatives in the rats. The results obtained were as followings. 1) Body weight was significantly reduced by retinoic acid, but not by retinoid. 2) Retinoic acid markedly increased liver weight while retincid showed no effect on liver weight. Treatment of riboflavin tetrabutylate did not affect retinoic acid-induced change in both body weight and liver weight. 3) Both retinoic acid and retinoid remarkably decreased the activity of aminopyrine demethylase. Pretreatment of riboflavin tetrabutylate, however, prevented inhibitory effect of retinoic acid on the enzyme activity. 4) No significant effect of vitamin E on aminopyrine demethylase was observed in both groups treated with retinoic acid and retinoid.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.5
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• pp.57-67
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• 2013

The studies of Korean traditional gardens have been a lot of diachronic approaches through ancient documents and on-site investigation. Previous research has focused on the characteristics that are inherent symbolism of the traditional landscape space, such as site characteristics. There are many studies for inner gardens, outer gardens and other influential ranges of gardens of the location characteristics. However, studies on the scale of external gardens were not satisfactory from a quantitative perspective. Unlike private life sphere, quantitative analysis was conducted on the role of a sphere of public community life for outer gardens. Visibility analysis was performed through the existing literature and GIS programs to estimate the magnitude of the outer garden. When it was compared with Min G. H.(1982) research, it is almost the same if it is estimated to focus on Buyoung -bong(芙蓉峯) and Ip-am(立巖). Also, as a result of the fractal structure for a variety of symbols in the garden, fractal dimension in landscape elements is relatively concentrated, unlike in other areas. Thus, the external scale can be a means of cultural property protection out of the crucial perspective for the inner garden. There has been consideration of the cooperation with the visual complexity using the concept of fractal structure as one of the elements of landscape analysis.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.9-18
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• 2014

These test methods, the current domestic vehicles fuel economy calculation method is tested on a dynamometer for vehicles after you have installed the vehicle, given the test mode(FTP-75 & HWFET mode, etc.) are measured by vehicle emissions and fuel economy by seeking to have the results approach, the carbon balance method. At this point, using the carbon balance method is a test method was developed seeking fuel for a standard fuel properties, where the value of the constant and saved test was measured in THC, CO, $CO_2$ has a value calculation. Therefore, use fuel which is changed every time you test the fuel properties characteristics are not considered exactly. In this study, using the carbon balance method and fluid flow rate of the fuel used in the actual test is measured by comparing the results with the flow measurement methods, properties of the fuel used for the test attribute to study ways that can be considered, taking into account the physical attributes of a more diverse fuel line and fuel economy improved measurement methods that can be reviewed.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.362-362
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• 2014

Atomic layer deposition (ALD) can be regarded as a special variation of the chemical vapor deposition method for reducing film thickness. ALD is based on sequential self-limiting reactions from the gas phase to produce thin films and over-layers in the nanometer scale with perfect conformality and process controllability. These characteristics make ALD an important film deposition technique for nanoelectronics. Tantalum pentoxide ($Ta_2O_5$) has a number of applications in optics and electronics due to its superior properties, such as thermal and chemical stability, high refractive index (>2.0), low absorption in near-UV to IR regions, and high-k. In particular, the dielectric constant of amorphous $Ta_2O_5$ is typically close to 25. Accordingly, $Ta_2O_5$ has been extensively studied in various electronics such as metal oxide semiconductor field-effect transistors (FET), organic FET, dynamic random access memories (RAM), resistance RAM, etc. In this experiment, the variations of chemical and interfacial state during the growth of $Ta_2O_5$ films on the Si substrate by ALD was investigated using in-situ synchrotron radiation photoemission spectroscopy. A newly synthesized liquid precursor $Ta(N^tBu)(dmamp)_2$ Me was used as the metal precursor, with Ar as a purging gas and $H_2O$ as the oxidant source. The core-level spectra of Si 2p, Ta 4f, and O 1s revealed that Ta suboxide and Si dioxide were formed at the initial stages of $Ta_2O_5$ growth. However, the Ta suboxide states almost disappeared as the ALD cycles progressed. Consequently, the $Ta^{5+}$ state, which corresponds with the stoichiometric $Ta_2O_5$, only appeared after 4.0 cycles. Additionally, tantalum silicide was not detected at the interfacial states between $Ta_2O_5$ and Si. The measured valence band offset value between $Ta_2O_5$ and the Si substrate was 3.08 eV after 2.5 cycles.

• Food Science and Preservation
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• v.22 no.6
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• pp.817-822
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• 2015

This study investigated the physical, textural, and sensory properties of strawberry jam with different amounts (0%, 14%, and 21%) of added rice mash. The soluble solids, pH, and total acidity values of the samples were found to be in the range of $53.00{\sim}65.33^{\circ}Brix$, 4.11~4.20 and 0.66~0.80%, respectively. Soluble solids and total acidity decreased significantly as the amount of rice mash was increased. The L-value, a-value, and b-value increased on increasing the amount of rice mash (p<0.05). The glucose contents of the samples ranged from 3.86 g to 4.13 g. The fructose, sucrose, and maltose contents significantly decreased (p<0.05). The organic acid content was measured and it was found that, oxalic acid was not in the control sample (0% rice mash). As the rice mash content was increased, the succinic acid content also increased (p<0.05), but the citric acid content decreased significantly (p<0.05). In the sensory evaluation, strawberry jam with rice mash showed superior spreading property than that of the control sample. Strawberry jam with 0% rice mash had the highest color and taste score. For the overall acceptability, strawberry jams with 0% and, 14% of rice mash were preferable to that with 21%.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.147-154
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• 2014

Consecutive pepper cultivation in plastic film houses may lead to salt accumulation because pepper is considered a heavy nutrient feeder. For this reason, appropriate methods of fertilizer application should be established. Thus, we investigated the effect of different intervals of side-dressing N and K fertilizer applications on soil and red pepper in a plastic film house. All the amounts of recommended compost and phosphorus fertilizer were applied as basal dressing. Cultivars of the pepper plant were Cheon-Ha-Dae-Se (CHDS) and NW-BiGaLim (NW-BGL). Nitrogen and potassium fertilizers were treated as side-dressing at different intervals, 22 times in every 10 days, 15 times in every 15 days, and 11 times in every 20 days. Soil pH decreased with decreasing the intervals of side-dressing applications, whereas electrical conductivity (EC) declined with the increasing fertilizer application intervals. In particular, EC value decreased by up to 75% with CHDS cultivar in the plot of 20 day-interval and with NW-BGL cultivar in the plot of 15 day-interval. The concentrations of available phosphorus in the soils increased with increasing the interval. The concentration of exchangeable $K^+$ increased but exchangeable $Ca^{2+}$ and $Mg^{2+}$ decreased in all the plots, except in the control plot. The concentrations of nitrogen and phosphorus in leaves of the pepper plants were lowest in the control plot. Potassium concentrations in the pepper leaves were high in the control plot and in the plots of CHDS with 10 day-interval and NW-BGL with 15 day-interval. Red pepper productivity was high in the plots of 10- and 15 day-intervals for CHDS cultivar and 15- and 20 day-intervals for NW-BGL cultivar. Therefore, the 15 day-interval of side-dressing N and K applications was considered as an appropriate method for cultivating pepper plants and protecting soil in plastic film houses.