• Journal of the Korean earth science society
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• v.40 no.2
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• pp.109-118
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• 2019

Cloud-aerosol interactions are considered to be one of the most important forcing mechanisms in the climate system. However, there is considerable disagreement on the magnitude and even on the sign of how aerosol perturbations affect cloud fraction and lifetime. Furthermore, aerosol effects on clouds and precipitation are not readily separable from the effects of meteorology. This review paper summarizes the study of precipitation susceptibility $S_o$, which qualifies how aerosol perturbations alter the magnitude of the precipitation rate (R) while minimizing the effects of macrophysical factors such as cloud depth (H) and liquid water path (LWP). The analysis shows that the precipitation susceptibility $S_o$ for the warm marine boundary layer clouds is insensitive to aerosol perturbations at low LWP (equivalently low H). However, R decreases as aerosols increase at intermediate LWP. This is because aerosols act as cloud seed and produce numerous small-sized particles, which impede the collision and coalescence process that leads to precipitation. At high LWP, $S_o$ decreases with increasing LWP as there are enough water contents in the clouds. The LWP or H dependent $S_o$ behavior differs depending on the predominant cloud physics processes in the clouds.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.661-667
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• 2001

Though a consensus seems to exist about the regulation of the use of sugar-containing food, however. an unrecognized and significant supply of cariogenic carbohydrate remains in the form of sugar-containing liquid oral medicine to prevent dental caries. children who are taking long-term sugar-containing liquid medicine have an increased risk of developing dental caries. The aim of this study is to get the information about the sugars in liquid medicines prescribed for the children. To get the information, the number and date of all prescriptions of liquid medicines for one month at pediatric hospital of Seoul National University Hospital were investigated. From that data, the most frequently used pediatric oral liquid medicine is presented. Then, for the information of the type and contents of sweeteners in that preferred medicines, the manufacturers of each medicines were asked for the data of sugar types and contents, and the informations about the medicine contents were collected via facsimile. The most frequently used pediatric oral liquid medicine were followed as expectorant, purge, antibiotic, drug for iron deficiency anemia, sedative, antihistamine, anticonvulsant, NSAIDs in order. The mean value of sweetener content in liquid medicines was $52.3{\pm}22.4g/100ml$ and most frequently used sweetener is sucrose.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.3
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• pp.66-73
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• 2004

As a rocket propellent of hydrocarbon fuels, the characteristics of liquefied natural gas was evaluated with the viewpoint of the constituents and content, the cooling performance as a coolant, and characteristic velocity and specific impulse as parameters of the engine performance. Content of methane was a principal factor to determine the characteristics as a rocket propellant and more than 90% of it was needed as a fuel and coolant in the regenerative cooled liquid rocket engine. Some constituents of the liquefied natural gas can be frozen by the pre-cooling of the pipe lines, therefore they can be a factor disturbing the normal working of engine. In case the content of methane is around 90% in the liquefied natural gas, a normalized stoichiometric O/F mixture ratio of 0.75 is suggested for a nominal operation condition to get the maximum specific impulse and characteristic velocity.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.122-122
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• 2009

금속기판과 액체금속의 젖음성은 일반적으로 액적법 (sessile drop)에 의해 고체와 액체간의 접촉각 측정을 통해서 알 수 있다. 이러한 방법에 의한 젖음성 실험결과는 고체와 액체계면에서의 반응이 무시될 수 있는 경우에 적용가는 하지만 연속용용도금공정과 같이 용융된 금속내부로 강판이 인입되는 과정에서 계면반응이 동적으로 진행되는 과정에서의 젖음성을 모사하기에는 이러한 방법의 신뢰성이 떨어지는 문제점이 있다. 따라서 본 연구에서는 실제 용융도금공정과 유사하게 소둔열처리된 저탄소강판이 환원성분위기내에서 Zn 및 Zn-Al 용융도금욕 내부로 연속적으로 인입되는 과정에서의 젖음력 및 접촉각 등의 측정을 통해 실제 도금공정상의 도금성과 젖음성의 연관성을 규명하고자하였다. 연구결과 일반적인 Zn 도금욕의 경우 젖음성이 양호하지만 Al함량이 높은 경우에는 젖음성이 좋지 못한 것으로 나타났다.

• Nuclear Engineering and Technology
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• v.3 no.1
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• pp.9-13
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• 1971

The levels of strontium-90 in milk produced in Korea were determined during the past six years. Milk samples were collected from dairies and market shops in seoul area. Strontium-90 in milk was separated from calcium using fuming nitric acid and purified radiochemically. After seculear equilibrium was completed, the radioactivity of yttrium-90 was counted in a low background beta counting system. The determination of stable calcium in milk was also made by volu-metric method using 0. 1 N potassium permanganate solution. The highest value of 34.9 pCi $^{90}$ Sr/g-Ca was determined in August, 1966 and the lowest value was 7.5 pCi $^{90}$ Sr/g-Ca in August, 1967. From the result we can say that levels of strontium-90 are decreasing year after year and are far bellow the maximum permissible level recommended by International Committe on Radiation Protection.

• Journal of the Mineralogical Society of Korea
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• v.13 no.1
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• pp.44-52
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• 2000

천연에서 발견되는 geversite (PtSb2), stumpflite (PtSb), insizwaite (PtBi2), unnamed PtBi 등의 광물에 대한 안정영역과 원소치환에 따른 고용체 존재를 규명하기 위해 백금-안티모니-비스머스 등 3성분계에 대한 합성실험적 연구를 실시하였다. 이번 연구에서 설정된 $600^{\circ}C$ 온도의 실험결과에 의하면, 등축정계의 geversite와 insizwaite 사이에 완전고용체가 형성되며, Sb를 치환하는 Bi의 함량에 따라 단위포 상수는 6.4415(0 at.%), 6.4361(15 at.%), 6.5204(30 at.%), 6.5411(51 at.%), 6.6261(70 at%), 6.6540(85 at%), 6.728$\AA$(100 at.%)로 증가함을 알 수 있었다. 육방정계인 stumpflite와 unnamed PtBi 사이에도 완전고용체가 형성되며, Sb를 치환하는 Bi의 함량이 증가함에 따라 a 단위포 상수의 크기는 4.1388(0 at.%), 4.2118(20 at.%), 4.2118(40 at.%), 4.2485(80 at.%), 4.3242$\AA$(100 at.%)등 연속적으로 증가하지만, c 단위포 상수는 각각 5.4902, 5.4799, 5.508, 5.4817, 5.5045$\AA$등 불규칙하게 변함을 알 수 있었다. 0~33.33 at.% Pt 영역에서의 상평형 관계는 액체가 Pt(Sb,Bi)2 고용체와 공존하고 있고, Sb가 많이 함유된 액체에서는 geversite+원소광물 안티모니+백금이 거의 함유되지 않은 액체와 공생하는 3-phase assemblage를 형성한다. 자연계에서는 geversite와 insizwaite 및 stumpflite와 unnamed PtBi 사이의 화학조성을 가지는 광물이 발견되고 있는데, 이들은 각각 독립적인 광물종이 아니라 위 광물들의 고용체에 속하는 것임을 알 수 있었다. 이들 광물을 명명하고 해석하는데 매우 세심한 주의가 필요함을 알 수 있었다. 또한 단위포 상수를 측정을 통해 해당 고용체 광물의 Sb↔Bi 치환 양을 추정할 수 있다는 점과 광물 공생관계를 통해 생성온도를 추정할 수 있다는 사실을 알 수 있었다.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.165-168
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• 1984

The three kinds of Kochujang were prepared with liquid koji equivalent to 30, 50 and 70% of brewing water and the composition of fatty acid and alcohols in the Kochujang aged at $25^{\circ}C$ for 3 months were compared with solid koji Kochujang. Palmitic, oleic and linoleic acid were found in all Kochujangs; but myristic, stearic and linolenic acid were detected in only the 50 and 70% liquid koji group. The predominant fatty acid of all Kochujang was linoleic acid, followed by oleic and palmitic acid. The total percentage of linoleic acid in the Kochujang was 58.47-83.39%. Linolenic, myristic and stearic acid were less than 3%. Ethyl, iso-butyl and iso-amyl alcohol were detected from all kinds of Kochujang. Iso-propyl alcohol was found in the Kochujang prepared from solid koji and 30% liquid koji. The contents of iso-butyl and iso-amyl alcohol were high in solid koji Kochujang and 50% liquid koji Kochujang. There were no significant difference in the contents of ethyl alcohol among tested Kochujangs.

• Korean Journal of Plant Tissue Culture
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• v.24 no.3
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• pp.137-142
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• 1997

In order to elucidate the optimum medium on the growth and tropane alkaloid production of hairy root, hairy root were induced by inoculating leaf and stem of Datura stramonium var. tatula Torr. with Agrobacterium spp. Both Agrobacterium tumefaciens $\textrm{A}_{4}$ T and A, rhizogenes ATCC 15834 among tested strains were effective on hairy root formation. Among 23 clones selected in SH (Schenk and Hildebrandt, 1972) liquid medium, DTLA9 clone was shown fast growth of hairy root and DTLE6 clone was shown high level production of tropane alkaloids. When both DTLA9 and DTLE6 clones were cultured in the GD (Gresshoff and Doy, 1972) medium, alkaloid production was higher than in 8 tested media. It was elucidated that optimum medium for root proliferation and for tropane alkaloid production is SH, GD medium, respectively.

• Journal of Mushroom
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• v.10 no.1
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• pp.3-8
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• 2012

In this study, to produce Flammulina velutipes mushroom liquid spawn efficiently and effectively the effects of explosive aeration (supplying air with tiny bubbles) of the liquid culture medium on carbon dioxide concentration and residual sugar content in the medium on carbon dioxide concentration and residual sugar contentin the medium were measured. Carbon dioxide concentrations were measured at the outlet of the incubator. On the third day the explosive aeration greatly increased mycelial growth of the liquid spawn, and carbon dioxide concentration also greatly increased but decreased after 5 days. Free sugar contents in the liquid culture consistantly decreased up to 7 days and thereafter was not detected. The weight of the mycelia were maintained similar levels after 3 days. Total nitrogen content in the liquid medium constantly decreased during the 11days of explosive aeration. The content of free sugars in 7 days of culture was the lowest level, thus the inoculum incubated for 6~7 days was thought to be the most effective. Carbon dioxide concentration measurement at the outlet of the container during the liquid spawn incubation required low cost but was efficient to estimate the degree of mycelial growth to be used as a simple indicator.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.348-352
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• 1984

Sesamolin and sesamin in the five domestic varieties and seven of imported sesame seed were analyzed by High Performance Liquid Chromatography to evaluate quality of sesame oil. Their stability against roasting, changes of content during storage of sesame oil and differences in carry-through ratio by extracting method were also analyzed. The results indicated that the HPLC method was simple, rapid and reliable in the evaluation of sesame oil quality.