• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.115-125
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• 2022

Flavonoids are bioactive plant metabolites that have a range of beneficial effects on human health. Quercetin 4'-glycoside (Q4'G), quercetin 3,4'-diglycoside (Q3,4'G), and quercetin aglycone (QA) are the main flavonoids found in onions. QA, in particular, is likely to have a greater biological effect than glycosides. To develop an onion extract with high quercetin content, the optimal extraction conditions for red onion powder containing the outer layer of the onion were determined. The effects of acid treatment on the concentration of quercetin glycosides and QA were evaluated. The flavonoids of red onion powder were optimally extracted under 60-70% ethanol at 70℃ for 2 h. The deglycosylation of Q3,4'G and an increase in Q4'G content occurred within 6 h of 0.2% acetic acid treatment. The QA content and deglycosylation of Q4'G eventually peaked at 24 h. In addition, QA content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were highly correlated, with a correlation coefficient of 0.90.

• The Journal of Engineering Geology
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• v.31 no.4
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• pp.701-718
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• 2021

Geological field surveys and a series of laboratory tests were conducted to obtain data related to landslides in Sancheok-myeon, Chungju-si, Chungcheongbuk-do, South Korea where many landslides occurred in the summer of 2020. The magnitudes of various factors' influence on landslide occurrence were evaluated using logistic regression analysis and an artificial neural network. Undisturbed specimens were sampled according to landslide occurrence, and dynamic cone penetration testing measured the depth of the soil layer during geological field surveys. Laboratory tests were performed following the standards of ASTM International. To solve the problem of multicollinearity, the variation inflation factor was calculated for all factors related to landslides, and then nine factors (shear strength, lithology, saturated water content, specific gravity, hydraulic conductivity, USCS, slope angle, and elevation) were determined as influential factors for consideration by machine learning techniques. Minimum-maximum normalization compared factors directly with each other. Logistic regression analysis identified soil depth, slope angle, saturated water content, and shear strength as having the greatest influence (in that order) on the occurrence of landslides. Artificial neural network analysis ranked factors by greatest influence in the order of slope angle, soil depth, saturated water content, and shear strength. Arithmetically averaging the effectiveness of both analyses found slope angle, soil depth, saturated water content, and shear strength as the top four factors. The sum of their effectiveness was ~70%.

• Journal of Korea Foresty Energy
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• v.20 no.1
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• pp.6-11
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• 2001

In order to use bast fibers of mulberry tree at a pulp source of Hanji, the bast fibers were microbiologically treated with several wood rot fungi, and the microscopic characteristics of bast fibers depending on treatment days were evaluated. By wood rot fungi, Phanerochaete chrysosporium and Trametes versicolor, the weight reduction ratio was approximately 50 percent within incubation for 20 days. occurring together with decomposition of useful fibers. However, Hwterobasidion insularis and Stereum hirsutum have completely decomposed the utmost layer of black blue colored bast fibers, and not caused the damage if fibers. Until incubation for 10 days, the cellulose content of vast fibers by Stereum hirsutum was 78.9 percent with lignin content of 7.2 percent, showing an appropriate decomposition for useful fibers. By microscopic observation, the bundled fibers were separated to single fiber within treatement days 30 by Pleurotus ostreatus, and there were no damage on the surface of fiber by treatment days 50.

• 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 the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.530-539
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• 1994

All lipoproteins are made up of three major classes of lipids : triglycerides, cholesterol, and phospholipids. Lipoproteins vary in their relative content of these lipids as well as in size and protein content. Human low density lipoprotein (LDL) is a main carrier for cholesterol in the blood stream, and it is well established that cholesterol deposits in the arteries stem primarily from LDL and that increased levels of plasma LDL correlated with in increased risk of atherosclerosis. Various lines of research provide strong evidence that lDL may become oxidized in vivo and that oxidized-LDL is the species involved in the formation of early atherosclerotic lesions. the most crucial findings in this context are the following : (1) Oxidized -LDL has chemotactic properties and if present in the intimal space of the arteries would recruit blood monocytes which then can develop into tissue macrophages ; (2) marcrophages take up oxidized-LDL unregulated to from lipid laden foam cells ; (3) Oxdized-LDLis highly cytotoxic and could be responsible for damage of the endothelial layer and for the destruction of smooth muscle cells.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.spc1
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• pp.145-165
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• 1996

Amaranth(Amaranthus spp. L.) and quinoa (Chenpodium quinoa Willd.) are old crops from South, Central America and Central Asia and their grains have been identified as very promising food crops because of their exceptional nutritive value. Squalene is an important ingredient in skin cosmetics and computer disc lubricants as well as bioactive materials such as inhibition of fungal and mammalian sterol biosynthesis, antitumor, anticancer, and immunomodulation. Amaranth has a component called squalene (2,6,10,15,19,23-hexamethyl-2,6,10,14,22-tetraco-sahexaene) about 1/300 of the seed and $5\~8\%$ of its seed oil. Oil and squalene content in amaranth seed were different for the species investigated. Squalene content in seed oil also increased by $15.5\%$ due to puffing and from 6.96 to $8.01\%$ by refining and bleaching. Saponin concentrations in quinoa seed ranged 0.01 to $5.6\%$. Saponins are located in the outer layers of quinoa grain. These layers include the perianth, pericarp, a seed coat layer, and a cuticle like structure. Oleanane-type triterpenes saponins are of great interest because of their diverse pharmacological properties, for instance, anti-inflammatory, antibiotic, contraceptive, and cholesterol-lowering effects. It is known that quinoa contains a number of structurally diverse saponins including the aglycones, oleanolic acid, hederagenin, and phytolaccagenic acid, which are new potential in gredient for pharmacological properties. It is likely that these saponin levels will be considerably affected by genetic, agronomic and environmental factors as well as by processing. With the current enhanced public interest in health and nutrition amaranth and quinoa will most likely remain in the immediate future within the realm of exotic health foods until such time as agricultural production meets the quantities and qualify required by industrial food manufacturers.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.77-82
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• 2004

In this paper, warpages of heterogeneous LTCC substrates comprised of high K/low K hi-layered structure were investigated. The effect of glass content in high K LTCC layer on the warpage of substrate during co-firing process was examined. Shrinkage and dielectric properties of high K and low K green sheets were measured. In-situ camber observation by hot stage microscopy showed different camber development of heterogeneous LTCC substrates according to glass content in high K green sheet. High K green sheet containing $50\%$ glass was matched to low K green sheet in the shrinkage. Therefore, LTCC substrate of Low K/High K+$50\%$ glass structure showed flat surface after sintering.

• Journal of Surface Science and Engineering
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• v.37 no.2
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• pp.80-85
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• 2004

Chromium-carbon (Cr-C) and chromium-carbon-phosphorus (Cr-C-P) alloy deposits using trivalent chromium sulfate baths containing potassium formate were prepared to study their current efficiency, hardness change and phase transformations behavior with heat treatment, respectively. The current efficiencies of Cr-C and Cr-C-P alloy deposits increase with increasing current density in the range of 15-35 A/dm$^2$. Carbon content of Cr-C and phosphorous of Cr-C-P layers decreases with increasing current density, whereas, the carbon content of Cr-C-P layer is almost constant with the current density. Cr-C deposit shows crystallization at $400^{\circ}C$ and has (Cr+Cr$_{ 23}$$C_{6}$) phases at $800^{\circ}C$. Cr-C-P deposit shows crystallization at $600^{\circ}C$ and has (Cr+Cr$_{23}$ $C_{6}$$+Cr_3$P) phases at $800^{\circ}C$. The hardness of Cr-C and Cr-C-P deposits after heating treatment for one hour increase up to Hv 1640 and Hv 1540 and decrease about Hv 820 and Hv 1270 with increasing annealing temperature in the range of $400～^{\circ}C$, respectively. The hardness change with annealing is due to the order of occurring of chromium crystallization, precipitation hardening effect, softening and grain growth with temperature. Less decrease of hardness of Cr-C-P deposit after annealing above $700^{\circ}C$ is related to continuous precipitation of $Cr_{23}$ $C_{6}$ and $Cr_3$P phases which retard grain growth at the temperature.

• Journal of Mechanical Science and Technology
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• v.15 no.5
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• pp.630-638
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• 2001

The electrical resistivity of sinter dusts generated from the steel industry and coal fly ash from the coal power plant has been investigated using the high voltage conductivity cell based on JIS B 9915 as a function of temperature and water content. Dust characterization such as the chemical composition, size distribution, atomic concentration, and surface structure has been conducted. Major constituents of sinter dusts were Fe$_2$O$_3$(40∼74.5%), CaO (6.4∼8.2%), SiO$_2$(4.1∼6.0%), and unburned carbon (7.0∼14.7%), while the coal fly ash consisted of mainly SiO$_2$(51.4%), Al$_2$O$_3$(24.1%), and Fe$_2$O$_3$(10.5%). Size distributions of the sinter dusts were bi-modal in shape and the mass median diameters (MMD) were in the range of 24.7∼137㎛, whereas the coal fly ash also displayed bi-modal distribution and the MMD of the coal fly ash was 35.71㎛. Factors affecting resistivity of dusts were chemical composition, moisture content, particle size, gas temperature, and surface structure of dust. The resistivity of sinter dusts was so high as 10(sup)15 ohm$.$cm at 150$\^{C}$ that sinter dust would not precipitate well. The resistivity of the coal fly ash was measured 1012 ohm$.$cm at about 150$\^{C}$. Increased water contents of the ambient air lowered the dust resistivity because current conduction was more activated for absorption of water vapor on the surface layer of the dust.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1503-1509
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• 2010

Forty-eight 40-wk-old Hi-sex laying hens were individually caged in an environmentally controlled house to evaluate the effect of garlic (Allium Sativum) juice administration on egg production, egg quality, and yolk cholesterol. Garlic juice was prepared by blending pealed garlic cloves with distilled water (1:1, w/w). Hens were randomly divided into four equal groups; one served as a control and the other three groups were individually gavaged, 3.75 ml, 7.5 ml, or 15 ml garlic juice, three times a week, which respectively represented 0.25, 0.50 and 1% of body weight. Egg production was recorded on a daily basis; egg weight, albumen height, albumen and yolk pH, Haugh unit, and bacterial count of E. coli-challenged eggs were recorded at day of oviposition (day-1) and after 5 and 10 days of storage at room temperature. Yolk cholesterol content was analyzed for five successive weeks. Garlic juice increased (p<0.05) egg weight and mass with no change in egg production intensity. Garlic juice administration recorded higher (p<0.05) albumen height and improvement in Haugh unit. Also, eggs from garlic-treated hens recorded lower (p<0.05) albumen and yolk pH when compared to eggs collected from control hens. Garlic reduced (p<0.05) the $log_{10}$ of bacterial count in egg contents linearly when challenged with E. coli. Egg-yolk cholesterol content was not influenced by garlic juice administration. It is concluded that garlic juice improved performance characteristics and may increase egg shelf life as indicated by egg quality improvement and lower bacterial count of E. coli-challenged eggs. The levels of garlic juice used in this study were insufficient to influence egg yolk cholesterol.