• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.166-170
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• 2006

본 연구에서는 폐광산 주변에 산재되어 있는 광미/광폐석을 처리하기 위하여 고형화 실증 실험을 수행하였다. 고형화 공정에서 흔히 사용하는 포틀랜드 시멘트와 MSG-E, MSG-N을 고화제로 사용하였으며 현장 광미 및 광폐석을 대상으로 고화체를 양생하고 고화체의 압축강도 및 중금속 용출 정도를 측정하였다. 고화체의 물리/화학적 특성을 비교하기 위해 광미/고화제 비율, 배합수/고화제 비율 그리고 고화체 양생기간을 실험인자로 설정하였다. 실험 결과 광미/고화제의 비율 1:1 만을 고려하더라도 중금속 용출의 급격한 감소가 이루어지는 것을 확인할 수 있었으며 광미/고화제의 비율을 3:1 이하로 유지시키는 경우, 고화체의 압축강도가 현행 폐기물 관리법(20조 관련)에서 규정하고 있는 차단형 매립시설 내부막의 압축강도 기준인 $0.21kgf/mm^2$ 보다 높은 것으로 나타났다. 다양한 pH를 갖는 수용액에 대하여 시간에 따른 고화체의 중금속 용출률을 측정한 결과, 수용액의 pH가 1과 13인 강산/강염기 용액에서 일부 중금속의 용출 농도가 지하수 생활용수 기준치를 초과하였으나, pH와 3 - 11인 경우에는 중금속 용출률이 급격히 감소하여 모두 기준치 이하를 나타내었다. 또한, pH가 1과 13인 수용액의 경우에도 고화체와 반응하는 시간이 증가할수록 고화체의 buffering 효과에 의해 수용액의 pH가 감소하였다. 이러한 결과는 현장에서 접촉수의 pH가 강산이나 강염기라 하여도, 고화체의 buffering 효과에 의해 시간이 지남에 따라 수용액의 pH가 낮아져 고화체로부터의 중금속 용출은 매우 감소할 것임을 의미한다.ss of an active application defined using the model. The technique is developed in a platform- and language-independent way, and it is algorithmic and can be automated by computer program. We give an example dealing with network auction to illustrate the use of the model and the verification technique.품으로 내부 온도분포를 측정하였으며, 유한차분법 프로그램으로 대류열전달계수를 결정하였다. 대류열전달계수는 792에서 2,107 W/m$^2$로 분석되었다. 대류열전달 계수는 액상식품과의 상대속도가 증가함에 따라서 증가하였고, 점도가 증가함에 따라서는 감소하였다.ce of precision/recall of 90.99%/92.52%, and 93.39%/93.41% respectively. 의한 변성에 부분적으로 보호 작용을 나타 낼 것으로 추정된다.경(製麴72時間頃)의 활성(活性)은 보리쌀국(麴), 밀가루국(麴), 찹쌀국(麴), 고구마국(麴)의 순이었다.험 결과 오전용 사료는 관행적인 산란계 배합사료에서 Ca공급제를 제외한 것을 급여하고, 오후용 사료는 Ca공급제를 3배 첨가한 T2처리로 15:00~16:00시에 교체급여를 하면 사료섭취량 감소와 사료비 절감면에서 바람직할 것으로 사료되며, 고에너지-고단백질-저Ca의 분말사료와 저에너지-저단백질-고Ca의 펠렛사료를 혼합급여하면 산란계의 사료

• Journal of Korea Water Resources Association
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• v.42 no.2
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• pp.117-129
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• 2009

Evaporation over the world is expected to increase owing to increase in temperature by global warming. However, pan evaporation around the world has decreased in the past few decades. This study, which has been conducted in 18 meteorological gauging stations in Korean peninsula, investigates the changes in pan evaporation and climate variables such as precipitation, temperature, relative humidity, wind speed, sunshine hours, and percentage of sunshine, which can affect evaporation processes; the changes in these variables have been recorded between 1960 and 2007. At most gauging stations, pan evaporation shows statistically significant downward trends. The relative humidity, wind speed, sunshine hours, and percentage of sunshine also show downward trends. On the other hand, precipitation and temperature show upward trends. The spatial distribution of the downward trend in sunshine hours and percentage of sunshine correspond to that of the downward trend in pan evaporation. Scatter plots imply that pan evaporation has a strong positive correlation with the sunshine hours and percentage of sunshine, while it has a negative correlation with precipitation. At the Gangneung gauging station, the open water evaporation estimated using the Penman equation does not show the significant downward trend shown by pan evaporation. This result implies that pan evaporation is not a good indicator of potential or open water evaporations during the investigation of their long-term variability. Finally, this study explains the complementary relationship between pan and actual evaporations. Decreases in the pan evaporation can act as an evidence for the ever-increasing actual evaporation.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.265-270
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• 1998

The curd yogurt was prepared from skim milk powder added with the juice, puree and powder, respectively, of the roots of Platycodon grandiflorum (Jacq.) A.DC. Twelve hours were proved to be best for fermentation of the curd yogurt, which showed 4.1 in pH and 1.15% in titratable acidity. Quality of the curd yogurt in sensory evaluation was best when 2 % of juice, 1 % of puree and 1 % of powder were added to the skim milk powder, respectively. When curd yogurt was kept at $5^{\circ}C$ for 9 days, pH decreased, while titratable acidity increased. The viscosity was highest with addition of puree 1%. After fermentation, number of viable cell was $6.2{\times}10^8/ml$ in control. $4.4{\times}10^8/ml$ in juice 2%, $3.7{\times}10^8/ml$ in puree 1% and $4.2{\times}10^8/ml$ in powder 1%. When curd yogurt was kept at $5^{\circ}C$ for 9 days, its keeping quality (pH, titratable acidity, viscosity and number of viable cells) were good.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.646-652
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• 2016

Biomass is regarded as one of the promising energy sources to deal with the depletion of fossil fuels and the global warming issue. Biocrude-oil can be produced through the fast pyrolysis of biomass feedstocks such as wood, crops, agricultural and forestry residues. It has significantly higher viscosity than that of conventional petroleum fuel and contains solid residues, which can lower the spray and atomization characteristics when applied to the burner. In addition, biocrude-oil consists of hundreds of chemical species derived from cellulose, hemicellulose and lignin, and evaporation characteristics of the biocrude-oil droplet are distinct from the conventional fuels. In the present study, a numerical study was performed to investigate the evaporation characteristics of biocrude-oil droplet using a simplified composition of the model biocrude-oil which consists of acetic acid, levoglucosan, phenol, and water. The evaporation characteristics of droplets were compared at various surrounding air temperatures, initial droplet diameters, and ethanol mixing ratios. The evaporation time becomes shorter with increasing air temperature, and it is much sensitive to the air temperature particularly in low temperature ranges. It was also found that the biocrude-oil droplet evaporates faster in cases of the smaller initial droplet diameter and larger ethanol mixing ratio.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.682-688
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• 2014

The in vitro digestibility and molecular and crystalline structures of rice starches (Seilmi, Dasan1, and Segoami) with differing amylose content were investigated. Segoami had the highest amylose content (30.9%), whereas Dasan1 had the lowest amylose content (21.2%). The molecular weight ($\bar{M}_w$) of amylose and amylopectin in Segoami was much lower than that of the other two rice starches. Segoami had the highest proportion (8.7%) of amylopectin short branch chains (DP 6-12) and the lowest proportion of B1 chains (DP 13-24). The relative crystallinity, intensity ratio of $1047-1022cm^{-1}$ (1047/1022) and gelatinization enthalpy followed the order: Segoami>Seilmi~Dasan1. Segoami showed substantially low pasting viscosity. Rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) contents showed the highest value in Seilmi, Dasan1, and Segoami, respectively. The expected glycemic index (eGI) of Segoami was lower than that of the other two rice starches. Overall results suggested that the digestibility of rice starch could be highly influenced by their molecular and crystalline structure.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.189-197
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• 2014

Onion juices were prepared by various heat treatments (at $105-120^{\circ}C$ for 4.5-5.5 h), from the onions cultivated with increasing numbers of sulfur applications (once for Sulfur-1, four times for Sulfur-4). As heat treatment intensity increased, the onion juices darkened (p<0.001), which adversely affected the sensory preference. In addition, increasing the heating temperature significantly increased the organic acid content of onion juices (p<0.001), and therefore, decreased pH (p<0.001). Heat intensity did not affect the thiosulfinate content of onion juices, suggesting that the rate of decomposition of thiosulfinate into low-molecular weight sulfur derivatives is similar over the temperature range of $105-120^{\circ}C$. Total flavonoids were higher in onion juices derived from Sulfur-4 than in Sulfur-1 onions, and increased with heat treatment intensity (p<0.001). These results indicated that heat-facilitated conversion of bound forms of flavonoids to their free forms increases the extractability of flavonoids from onions.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.51-56
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• 2002

This study was carried out to develop a traditional functional beverage by using hot-water extraction of dried peels of Korean tangerine. The pH of the hot-water extracts of dried tangerine peels decreased as the extraction time increased. The acidity and viscosity of the extracts increased as the extraction time increased. The antioxidative activity of the extracts during the extraction was monitored by measuring the electron donating ability. The electron donating abilities of the extracts were in the range of 80.93-83.27%. Extraction time did not affect the antioxidative activity of the extracts. The fibrinolytic activity of the extracts increased as the extraction time increased. The pH of the beverage made with the peel extract was not affected by the extraction time and the kind of sweetener added. The viscosity of the beverage increased as the extraction time increased. In sensory evaluation the highest score was obtained in the beverage samples made with the ones extracted for 180 min and added with sugar. The aboveresults indicate that the dried peel of Korean tangerine can be used as a functional material in beverage industry.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.252-261
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• 1983

Isopropyl alcohol extracted filefish protein concentrate (FPC) and NaOH hydrolyzed filefish protein isolate (FPI) were used for the investigation on the effect of processing conditions on the molecular distribution and functional properties. The molecular distribution of FPC on polyacrylamide gel showed a resemblance to that of fish muscle, but that of alkaline hydrolyzed FPI showed the severe degradation of protein. The content of several amino acids in FPI were lower than those of FPC. The pepsin digestibility of the FPC dried at high temperature was relatively high. FPC didn't exhibit a significant difference in nitrogen solubility at the pH range of 3.0-9.0, while FPI showed a wide difference with the pH change. FPI was more suspensible and rehydrated in water than FPC. Although the aeration capacity of FPI was very low, foam viscosity was higher than that of FPC. In contrast with aeration capacity, FPI presented higher emulsion capacity and lower emulsion viscosity than FPC. The size of fat globule in the emulsion of FPC was larger than that of FPI. In general, most functional properties decreased with the increment in drying temperature, except water holding capacity.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.255-265
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• 2012

This study aimed to determine the physicochemical and sensory qualities for yogurt dressing prepared with blueberry juice(0, 10, 15, 20, and 25%). As the amount of added blueberry juice increased, citric acid, malic acid and succinic acid contents increased, but tartaric acid, lactic acid and acetic acid contents decreased. The pH of control group(3.75) was higher than that of the others(3.68-3.48). Sweetness of yogurt dressings decreased as the amount of added blueberry juice increased. DPPH radical scavenging activity of the control group was 26.44%, whereas those of yogurt dressings with blueberry juice ranged from 63.16-87.46%. Color L and b values decreased significantly, whereas a value increased significantly by addition of blueberry juice. Viscosity of the control group was lower than those of the others. The sensory property results showed that yogurt dressing with 20% blueberry juice was rated best. It was also preferred most. These results suggest 20% of blueberry juice is the best substitution ratio for yogurt dressing.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.510-516
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• 1996

Cardiopulmonary bypass cannulas are usually characterized by the French number. However this de- scription provides only the external diameter of the cannula, which gives no information about the press- ure-flow characteristics of the cannula itself. A standardized system to describe the pressure-flow characteristics of a given cannula has recently been proposed and has been termed the M-number It is reported that the pressure-flow characteristics of a particular cannula can be determined from a novo- gram or chart, if the experimentally derived M-number of the cannula is known. In this regard, we conducted an investigation to analyze correlation between experimentally and clinical y derived M-numbers using three different sizes of pediatric aortic cannulas in fifty cardiac patients on cardiopulmonary bypass. The clinical and experimental M-numbers showed a strong correlation. The clinical M-numbers were typically 0.)5 to 0.55 greater than the experimental M-numbers. The clinical M-numbers also showed an inverse relationship to the temperature change of the patient, most probably due to an increase in blood viscosity from hypothermia. This inverse clinical M-numbersltemperature re- lationship was more marked in higher M-number cannulas. The clinical data obtained in this study suggest that the experimentally derived M-numbers correlated strongly with the clinical performance of the cannula with the significant influence of the temperature.