• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.307-313
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• 1986

This study was carried out in order to estimate the residual amount of mercury in soy-bean sprouts in each steps of cooking. Samples were taken at markets and also cultured at home without applying the mercury containing pesticides as control. Mercury was determined by dithizone method. It was disclosed that soy-bean sprouts purchased at markets contained $1.32{\pm}0.274ppm$, 13 times as high as the maximal allowable concentration of mercury in food recommeded by Ministry of Health and Social Affairs. Mercury contents, however, dropped off steadily by steps of cooking: rinsed with distilled water and boiled in distilled water showing concentrations of $0.11{\pm}0.025ppm$ in boiled sprouts and $0.03{\pm}0.022ppm$ in sprout-soup. These values were not statistically different from those in control samples, and not exceeded the maximal allowabled levels of mercury in food. It can be concluded that the use of mercury containing pesticides in the cultivation of soy-bean sprouts is not so serious problem as it has been suspected in respect of food contamination, but careful attention must be paid to indiscriminate use of mercury containing pesticides as they may contaminate air, water and soil and secondarily bring harm to human health through food chains.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.5
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• pp.384-392
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• 2006

Reported are the heat transfer characteristics of a two-phase loop thermosyphon (TLT) with nanofluids consisted of nano-size silver particles and distilled water as the working fluid. The nanofluids used in the present study are dispersed solutions with various amount of silver nanoparticle in distilled water. It is seen from the present study that the heat transfer performance of the test TLT with nanofluids increased as much as about 2 times higher than that of a TLT with pure water as the working fluid based on same heat flux. The study also showed that there was no deterioration of the TLT performance with time, up to a period of 8 days of continuous operation which implies that there was no coagulation of nanoparticles within the working nanofluid during the operation of the test TLT.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1594-1599
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• 2015

The world car industry is in an era of internal combustion engines in the past 100 years of environmental, energy and IT is eco-friendly, high-tech cars technologies are bringing an era of change. Until now, the study of new technologies in automobile research and development has been focused on. The car's new technology development is also important, but it's cutting-edge technology is used in the car before the car's performance, and became an important point in the customer experience improvement problems. New technology development, as well as effective for existing technology applied is also important. This study was to determine the effects of temperature and the performance of automobile engine and determine the cause of the content in accordance with the type(tap water, distilled water, underground water) of anti-freeze and water that is contained in the automotive engine cooling water for the effective application of the anti-freeze. In the freezing point of the coolant -10, -20, -30, -40, $-50^{\circ}C$ dynamo performance test was conducted with the numerical analysis. Water (distilled water) were measured at the reference point peak performance 71.112, 99.622hp freezing $-10^{\circ}C$.

• New & Renewable Energy
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• v.8 no.2
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• pp.24-32
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• 2012

Natural gas hydrates have a high potential as the 21st century new energy resource, because it have a large amount of deposits in many deep-water and permafrost regions of the world widely. Natural gas hydrate is formed by physical binding between water molecule and gas mainly composed of methane, which is captured in the cavities of water molecules under the specific temperature and pressure. $1m^3$ methane hydrate can be decomposed to the methane gas of $172m^3$ and water of $0.8m^3$ at standard condition. Therefore, there are a lot of practical applications such as separation processes, natural gas storage transportation and carbon dioxide sequestration. For the industrial utilization of methane hydrate, it is very important to rapidly manufacture hydrate. However, when methane hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. So in this study, hydrate formation was experimented by adding natural zeolite and Synthetic zeolite 5A in distilled water, respectively. The results show that when the Synthetic zeolite 5A of 0.01 wt% was, the amount of gas consumed during the formation of methane hydrate was higher than that in the natural zeolite. Also, the natural zeolite and Synthetic zeolite 5A decreased the hydrate formation time to a greater extent than the distilled water at the same subcooling temperature.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.4
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• pp.265-270
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• 2002

Most of all the mechanical devices are becoming more high-speed and high-power as well as their used condition being more pollution with rapid development in industrial part. So, it is necessary for these devices to equip cooling system to overcome that kind of severe using condition. Industrial development and income increase causes rapid increase in using fossilenergy and it results in accelerating environmental pollution owing to the increasement in emission of air pollution substance. Specially, fresh water like stream and river water is acidified. Therefore, corrosion damage is accelerated in radiator for automobile that is using acidified water. So, in this study, corrosion test was carried out in distilled and tap water for the investigation on the corrosion behavior of Al-alloy that is using as material for radiator of automobile The main results obtained are as follows According to increase of temperature, open circuit potential is decreased in fresh water. And open circuit potential after deaeration is lower than that before deaeration. Corrosion current density in distilled water is less drained than that of tap water. And Corrosion current density after deaeration is less drained than that before deaeration.

• Journal of the Korean Society for Environmental Technology
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• v.19 no.6
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• pp.493-502
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• 2018

The purpose of this study was to develop EM media for water treatment and to remove nitrogen and phosphorus which cause water algae boom in water system. The ideal mixing ratio of raw material such as clay: zeolite: vermiculite: activated carbon for manufacturing the EM media was 10: 2.5: 0.1: 2, and the calcination temperature was $700^{\circ}C$. The comparison of the physical properties of manufactures using distilled water and EM activated liquid as the material mixture are as follows. Porosity and density of EM media were 39.98 % and $1.13kg/m^3$, adsorption efficiencies of nitrogen and phosphorus were 69.3 % and 38.9 %. In contrast, porosity and density of distilled water media were 37.80 % and $1.11kg/m^3$, and adsorption efficiencies of nitrogen and phosphorus were 62.5 % and 37.8 %. The adsorption rate of nitrogen and phosphorus in the EM media was higher than that of the distilled water made one by 6.8 % and 1.1 %, respectively. The adsorption characteristics of the media to nitrogen and phosphorus could be expressed by the Freudlich adsorption isotherm. The change of calcination time did not affect the adsorption efficiency of phosphorus and nitrogen when EM media was formed, but it was considered that it affects the strength of media. Nitrogen removal efficiency was the best record in 4 hours of calcination time and 3 hours of calcination time in phosphorus removal efficiency.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.265-271
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• 2015

In a previous study, hydrolysates of porcine placenta were obtained and the extraction efficiency for proteins and amino acids was compared between sub- and super-critical water extraction systems; optimum efficiency was found to be achieved using subcritical water ($170^{\circ}C$, 10 bar). In this study, the effects of adding ethanol to the subcritical water system were investigated. The lowest-molecular-weight extraction product detected weighed 434 Da, and the efficiency of extraction for low-molecular-weight products was increased when either the concentration of ethanol was decreased, or the extraction time was lengthened from 10 min to 30 min. The highest concentration of free amino acids (approximately 8 mM) was observed following 30 min extraction using pure distilled water. The concentration of free amino acids was significantly lower when ethanol was added or a shorter extraction time was used (p<0.05). Color change of the solution following extraction was measured. There were no significant differences in color between lysates produced with different extraction times when using distilled water (p>0.05); however, using different extraction times produced significant differences in color when using 20% or 50% ethanol solution for subcritical extraction (p<0.05). The range of pH for the hydrolysate solutions was 6.4-7.5. In conclusion, the investigated extraction system was successful in the extraction of $\leq$ 500 Da hydrolysates from porcine placenta, but addition of ethanol did not yield higher production of low-molecular-weight hydrolysates than that achieved by DW alone.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.5
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• pp.439-446
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• 2003

Various volume of water for the optimal brewing condition of the Korean distilled liquor produced by liquefaction of rice and corn starch was investigated Pilot brewings were carried out by the liquefaction of 5kg of rice and 10kg of corn starch with 150%, 200% and 250% of water regarding the amount of rice and corn starch. The pH, alcohol production and total acidity were normal during the fermentation process. The yield was proportional to the amount of water added and the highest yield was obtained by 250% of water addition without loss of quality. All the test results were not significantly different by the one-way ANOVA and Duncan's multiple range test at p<0.05 and the flavor profiles were also not different according to the amount of water added. As a result, 250% of water addition was the most economical and optimal brewing condition in this study.

• Journal of Acupuncture Research
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• v.32 no.3
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• pp.117-126
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• 2015

Objectives : This study was an analysis of the anti-inflammatory, anti-oxidative and skin whitening properties of Gamioncheong-decoctione(GMOCD) extract. Methods : GMOCD(96 g) and 2 L of distilled water were heated at $100^{\circ}C$ for four hours and then concentrated, frozen, freeze-dried, dissolved in distilled water and filtered. The following analysis was completed: cell cytotoxic effect using MTT assay, oxidative products of NO by griess assay, concentration of prostaglandin $E_2(PGE_2)$ by commercially competitive enzyme immunoassay, and cytokines($IL-1{\beta}$, IL-6 and TNF-${\alpha}$) by Bio-Plex$^{(R)}$ Suspension Array System's Bio-Plex Pro$^{TM}$ mouse cytokine, chemokine, and growth factor assay. Anti-oxidative effect was measured using the DPPH method and skin whitening effect using tyrosinase inhibition assay. Results : GMOCD water-extract did not show any toxicity at all doses and cell viability was more than 90 % at all doses. GMOCD water-extract significantly inhibited NO production at doses of 100, 200, $400{\mu}g/ml$, significantly inhibited $PGE_2$ production at doses of 200 and $400{\mu}g/ml$ and reduced the LPS-induced IL-$1{\beta}$, IL-6 and TNF-${\alpha}$ production in a dose-dependent manner. $IL-1{\beta}$ production was significantly reduced at a dose of $400{\mu}g/ml$ and IL-6 production was significantly reduced at doses of 200 and $400{\mu}g/ml$. DPPH free radical scavenging capability had a skin whitening effect rate of more than 50%. Tyrosinase inhibition activity was apparent in a dose-dependent manner. Conclusions : This study suggests that GMOCD water-extract suppressed NO and $PGE_2$ production and inhibited cytokines($IL-1{\beta}$, IL-6 and TNF-${\alpha}$). GMOCD also improved DPPH free radical scavenging capability. GMOCD water-extract increased tyrosinase inhibitory activity in a dose-dependent manner but this was not a statistically significant result.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.111-117
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• 2005

Radical scavenging activity of water and methanol extracts of mulberry juice and cake prepared from mulberry fruit (Morus spp.) was evaluated using three in vitro assay systems. Mulberry fruits were homogenized with $0.5\%$ trifluoroacetic acid (TFA) in distilled water, filtered with cheeze-cloth and centrifuged to yield mulberry juice and cake. Mulberry juice was evaporated and solubilized in $0.5\%$ TFA in distilled water or $0.5\%$ TFA in $80\%$ aqueous methanol, followed by filtration and evaporation to obtain water (WMJ) and methanol (MMJ) extracts of mulberry juice. Mulberrry cake also was extracted with the above same solvents, and thereby finally obtaining water (WMC) and methanol (MMC) extracts of mulberry cake. Among four extracts, the MMC showed the most potent radical scavenging activity against DPPH radical $(IC_{50}=167.45\;{\mu}g/mL)$, and superoxide $(IC_{50}=36.18\;{\mu}g/mL)$ and hydroxyl radicals $(IC_{50}=467.08\;{\mu}g/mL)$. The WMC also exhibited stronger radical scavenging activity than those of two other mulberry juice extract, WMJ and MMJ. Meanwhile, the MMJ exerted stronger three radical scavenging activity than the WMJ. Total phenolic content of the water and MeOH extracts from mulberry cake was higher than that of the water and MeOH extracts from mulberry juice. Thus, these results suggest that the extracts of mulberry cake with high dietary phenolics may be useful potential source of natural antioxidant as radical scavenger.