• Journal of the Korean Chemical Society
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• v.42 no.3
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• pp.251-265
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• 1998

Punch'ong and whiteware sherds excavated from four kilns located in Ch'unghyodong, Kwangju, Chollanamdo were analyzed for their body and glaze composition. They are classified into eight different groups by the site and layer from which they were collected. In principal component analysis of major composition, the punch'ong body separates out into several different groups. CHE2, made in early fifteenth century, has a higher aluminum and lower iron content compared to the later groups of lower grade. Whiteware body has a very high aluminum content of around 30 wt. in both soft type and hard type. Punch'ong glaze was determined to be lime type and whiteware alkali-lime type.

• Journal of Energy Engineering
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• v.16 no.3
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• pp.120-127
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• 2007

The purpose of this study is experimentally to analyze that the fuel mass fractions of multi-component mixed fuels have an effect on the characteristics of spray ignition and combustion under the ambient conditions of diesel combustion fields. The characteristics of ignition and combustion were investigated by chemiluminescence images and direct photography. The experiments were conducted in the RCEM(rapid compression expansion machine) with optical access. Multi-component fuels mixed with i-octane, n-dodecane and n-hexadecane are injected in RCEM by the electronic control of common rail injector. Experimental conditions set up 42, 72 and 112 MPa in injection pressure, 700, 800 and 900 K in ambient gas temperature. The results show that the ignition delay was dependent on high cetane number. In case of low ambient temperature, the more low boiling point fuels were mixed, the lower luminance regime had a remarkable effect and also shortened diffusion combustion by increasing heat release rate.

• The Journal of the Korea Contents Association
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• v.13 no.4
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• pp.312-319
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• 2013

The purpose of this study was to evaluate the efficacy of gargle and toothpaste containing low concentration with sodium fluoride on the remineralization through the surface microhardness and mineral content in enamel. After 4 weeks-application, the enamel surface was measured using microhardness tester and the calcium (Ca) and phosphorous (P) concentration of mineral content by electron probe microanalyzer (EPMA) analysis. By combining fluoridated gargle with toothpaste, a remineralized enamel resulted in significantly significant differences among the four groups (p<0.05). The Ca change treated with 0.23% fluoridated toothpaste and 0.02% fluoridated gargle with 0.23% toothpaste demonstrated the highest among the other groups. In conclusion. the fluoridated gargle with toothpaste by low concentration showed a significantly greatest synergistic effect on remineralization of the enamel than the other groups.

• Journal of the Korean Chemical Society
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• v.30 no.4
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• pp.352-358
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• 1986

An extensive experimental survey on the retention behaviors of phenols in the binary solvent system such as methanol-water, acetonitrile-water and tetrahydrofuran-water as well as the ternary solvent system such as methanol-acetonitrile-water and methanol-tetrahydrofuran-water is presented. A linear equation, which describes the capacity factor as a function of the solvent composition in the mobile phase and is able to predict the retention behaviors of phenols, was obtained. The iso-eluotropic lines for the binary and ternary solvent system are based on the equal strength of the methanol-water solvent which shows an optimum separation of the phenols used. The specific effect of each solute in the binary solvent system appeared to be larger than those in the ternary system.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.400-403
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• 1997

The purpose of this study was to investigate the differences in proximate composition, free sugars, amino acids, fatty acids and Hunter color vaules between fresh and odorless garlic. The contents of crude fiber, crude fat and ash in odorless garlic were silmilar to those in fresh garlic. Sugars and crude protein decreased during manufacture of odorless garlic. Among the free sugars, sucrose, maltose and fructose decreased in odorless garlic, while the content of glucose increased. Total amino acid content decreased by about 30% in odorless garlic. Among the amino acids decreased arginine, isoleucine etc. The contents of linoleic acid, palmitic acid and oleic acid were higher than those of other fatty acids in fresh garlic and odorless garlic, but laruric acid was in little quantity. There were no singnificant differences in the Hunter L and b value between the fresh and odorless garlic, but value for greeness(-a) was lower in odorless garlic.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.641-647
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• 2017

In order to meet the stricter emission regulations, the proportion of after-treatments for vehicles and vessels has been increasing gradually. The objective of this study is to investigate the physicochemical properties according to ash cleaning agents of CDPF for Diesel Engines. Penetrating agents with strong penetration into ash and a surfactant component to mix water and oil were prepared properly. The cleaning characteristics of S1 sample were good. Washcoat loss rate of S1 sample was lower by about 2.2% because of less KOH component and lower Na2SiO3 content. Washcoat loss rate of S4 sample with an added KOH and Na2SiO3 components by penetration agents was increased by about 13%. In terms of less than about 13% of CDPF's washcoat loss rate, it was able to reduce the harmful gas components.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.647-653
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• 1997

To establish the index of aging stage for cold storage beef tenderloin, shear force value(SFV), Mg-ATPase activity, myofibrillar fragmentation index(MFI), myofibrillar fragmentation ratio(MFR) and appearance of 30KD(30KD) were measured as the parameters for the indices of aging stage. Aging index of air-packed beef tenderloin stored for 14 days at 3$^{\circ}C$ were useful in the order of SFV(r=-0.893)>MFR (r=0.863) >30KD(r=0.853)>MFI(r=0.814)>Mg-ATPase activity(г=0.804). Vacuum-packed beef tenderloin stored for 28 days at 3$^{\circ}C$ were useful in the order of MFR(r=0.880)>30KD(r=0.836). In case of the correlation between aging indices of air-packed beef tenderloin, MFR had relation with SFV, Mg-ATPase activity, MFI and 30KD. In case of the correlation between aging indices of vacuum-packed beef ten- derloin, MFR had relations with 30KD.

• Food Science and Preservation
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• v.6 no.4
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• pp.469-474
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• 1999

The chemical components of Hovenia dulcis leaf and fruit stalk naturally growing in Korea, were determined. Crude protein of leaf and total sugar of fruit stalk was 7.30 and 51.64%, respectively. The major mineral components were K, Ca, Mg, Na and Mn in that order. The content of vitamin C was 4.8 mg% for leaf and 3.8 mg% for fruit stalk and that of free sugar was 1.37% of fructose for leaf and 8.83% of sucrose for fruit stalk. The highest organic acid in leaf and fruit stalk was malic acid and its content was 1,715.21 mg% and 439.18 mg%, respectively. The highest component of total amino acids in leaf and fruit stalk was glutamic acid(497.99mg%) and proline(751.78mg%), respectively. The highest lady acid in leaf and fruit stalk was 43.54% of linolenic acid and 23.15% of palmitic acid, respectively. trans-Geraniol(124.36 ppm) and isobutyric acid(292.67 ppm) were predominant volatile compounds in leaf and fruit stalk, respectively.

• Journal of Mushroom
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• v.19 no.3
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• pp.115-125
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• 2021

Mushroom consumption causes changes in the immune system and gut microbiota via the actions of mushroom probiotic components. β-Glucan structure-related substances suppress secretion of inflammatory mediators, and induce macrophage activation, enhancing immunity and immune function. Substances other than directly useful components can be metabolized into short-chain fatty acids by gut microbiota. These short-chain fatty acids can then induce immunity, alleviating various diseases. Substances used to stimulate growth of health-promoting gut bacteria, thereby changing the gut microbiota community are defined to be probiotics. Probiotic altered intestinal microflora can prevent various types of bacterial infection from external sources, and can help to maintain immune system balance, thus preventing diseases. Research into beneficial components of Pleurotus eryngii, Lentinula edodes, Pleurotus ostreatus, Flammulina velutipes, Auricularia auricula-judae, and Agaricus bisporus, which are frequently consumed in Korea, changes in microbiota, changes in short-chain fatty acids, and correlations between consumption and health contribute to our understanding of the effects of dietary mushrooms on disease prevention and mitigation.

• Korean Chemical Engineering Research
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• v.53 no.1
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• pp.22-30
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• 2015

So far, most of research activities on modeling of membrane separation processes have been focused on binary feed mixture. But, in actual separation operations, binary feed is hard to find and most separation processes involve multicomponent feed mixture. In this work models for membrane separation processes treating multicomponent feed mixture are developed. Various model types are investigated and validity of proposed models are analysed based on experimental data obtained using hollowfiber membranes. The proposed separation models show quick convergence and exhibit good tracking performance.