• Journal of computational fluids engineering
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• v.15 no.3
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• pp.24-31
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• 2010

boiling flow in vertical tube. The multiphase flow model used in this CFD analysis is the two-fluid model in which liquid(water) and gas(vapour) are considered as continuous and dispersed fluids, respectively. A wall boiling model is also used to simulate the subcooled boiling heat transfer at the heated wall boundary. The diameter and heated length of tube are 0.0154 m and 2 m, respectively. The system pressure in tube is 4.5 MPa and the inlet subcooling is 60 K. The near-wall grid size in the non-dimensional wall unit for lqiuid phase ($y^+_{w,l}$) was examined from 101 to 313 at the outlet boundary. The CFD calculations predicted the void distributions as well as the liquid and wall temperatures in tube. The predicted axial variations of the void fraction and the wall temperature are compared with the measured ones. The CFD prediction of the wall temperature is shown to slightly depend on the near-wall grid size but the axial void prediction has somewhat large dependency. The CFD prediction was found to show a better agreement with the measured one for the large near-wall grid, e.g., $y^+_{w,l}$ > 300 at the tube exit.

• Food Science and Preservation
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• v.18 no.4
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• pp.590-596
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• 2011

Pimpinella brachycarpa, called as cham-na-mul in Korea, is an edible popular herb. However, the study of biological activity of P. brachycarpa is still rudimentary in worldwide. In this study, from the cultivated P. brachycarpa, we prepared the methanol extract and its subsequent solvent fractions, and their antimicrobial, antioxidation, and anti-proliferative activities were evaluated. The fraction yields of n-hexane (H), methylene chloride (EC), ethylacetate (EA), butanol (B), and water residue (W) from the methanol extract were 18.71, 0.7, 0.56, 4.57, and 71.51%, respectively. Analysis of total flavonoid and total polyphenol showed that the EA fraction contained the highest contents (89.23 and 200 mg/g), and the W residue has the lowest contents (19.6 and 2.27 mg/g) among the factions. In antimicrobial activity assay, the EA fraction showed a broad-range antibacterial activity, while the H fraction is effective against gram positive bacteria. In antioxidation activity assay, EA and B fraction showed strong DPPH anion and ABTS cation scavenging activities including reducing power, and Hand MC fraction showed effective nitrite scavenging activity (71.43~83.82 ${\mu}g$/mL of $IC_{50}$). In a while, only B fraction showed strong anti-proliferative activity against human colorectal cancer HCT-116 (166 ${\mu}g$/mL of $IC_{50}$) as a dose-dependent manner up to 200 ${\mu}g$/mL. These results suggest that the EA and B fraction of P. brachycarpa could be developed as functional food ingredients.

• YAKHAK HOEJI
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• v.27 no.4
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• pp.315-320
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• 1983

Ginseng proteins have been extracted and partially purified by the methods of ammonium sulfate fractionation, heat inactivation and Sephadex G-75 column chromatography. The final three fractions obtained (GI, GII and GIII) were subjected to paper chromatography and SDS-polyacrylamide gel electrophoresis. Molecular weights of polypeptide chains from each fraction were est-mated by the standard line obtained from the plot of electrophoretic mobilities against the logarithm of molecular weights of standard proteins. Results are as follows: 1) GI showed three protein spots and four polypeptides of which M.W. were 63,000, 60,000, 56,000, 51,000 and 34,200. 2) GII showed four protein spots and five polypeptides with their M.W. of 64,600, 56,000, 45,400, 35,800, end 25,200, 3) GIII showed three protein spots and four polypeptides with their M.W. of 66,000, 63,000, 56,000 and 22,000.

• Food Science and Preservation
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• v.11 no.3
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• pp.364-372
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• 2004

To investigate antioxidative effects of n-hexane fraction of Angelica acutiloba on the ethanol-induced hepatotoxicity of rats, Sprague-Dawley rats weighing 100 $\pm$ 20 g were divided into 5 groups; normal group(NOR), ethanol(10 mL/kg, 35$\%$) treated group(CON), n-hexane fraction of Angelica acutiloba 70 mg/kg treated group(Al), n-hexane fraction of Angelica acutiloba 70 mg/kg and ethanol treated group(A2) and n-hexane fraction of Angelica acutiloba 140 mg/kg and ethanol treated group(A3), respectively. The antioxidative activities of ethanol extract of Angelica acutiloba in vitro were decreased in order of n-hexane > ethylacetate > chlorofonn > n-butanol (>) water fraction. The growth rate and feed efficiency rate decreased by ethanol were gradually increased to the adjacent level of the normal group by administering n-hexane fraction of Angelica acutiloba. It was also observed that the activities of SOD of liver, ALT and AST of serum increased by ethanol were markedly decreased in n-hexane fraction of Angelica acutiloba administered group, and not in activites of XO, catalase, as compared with the control group. The depleted content of GSH by ethanol was increased adjacent to normal level by administering n-hexane fraction of Angelica acutiloba. as a dose-dependent manner. These results suggested that n-hexane fraction of Angelica acutiloba has a possible protective effect on the ethanol-induced hepatotoxicity of rats.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.808-811
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• 2004

A full-color AMOLED display with an RGBW color filter pattern has been fabricated. Displays with this format require about $^1/_2$ the power of analogous RGB displays. RGBW and RGB 2.16inch diagonal displays with average power consumptions of 180 mW and 340 mW, respectively, are demonstrated for a set of standard digital still camera images at a luminance of 100 cd/$m^2$. In both cases, a white-emitting AMOLED is used as the light source. The higher efficiency of the RGBW format results because a large fraction of a typical image can be represented as white, and the white sub-pixel in an RGBW AMOLED display is highly efficient because of the absence of any color filter. RGBW and RGB AMOLED displays have the same color gamut and, aside from the power consumption difference, are indistinguishable.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.4
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• pp.471-478
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• 2011

The objectives were to compare the ability of various rumen microbial fractions to reduce nitrate and to assess the effect of nitrate on in vitro fermentation characteristics. Physical and chemical methods were used to differentiate the rumen microbial population into the following fractions: whole rumen fluid (WRF), protozoa (Pr), bacteria (Ba), and fungi (Fu). The three nitrogen substrate treatments were as follows: no supplemental nitrogen source, nitrate or urea, with the latter two being isonitrogenous additions. The results showed that during 24 h incubation, WRF, Pr and Ba fractions had an ability to reduce nitrate, and the rate of nitrate disappearance for the Pr fraction was similar to the WRF fraction, while the Ba fraction needed an adaptation period of 12 h before rapid nitrate disappearance. The WRF fraction had the greatest methane ($CH_4$) production and the Pr fraction had the greatest prevailing $H_2$ concentration (p<0.05). Compared to the urea treatment, nitrate diminished net gas and $CH_4$ production during incubation (p<0.05), and ammonia-N ($NH_3$-N) concentration (p<0.01). Nitrate also increased acetate, decreased propionate and decreased butyrate molar proportions (p<0.05). The Pr fraction had the highest acetate to propionate ratio (p<0.05). The Pr fraction as well as the Ba fraction appears to have an important role in nitrate reduction. Nitrate did not consistently alter total VFA concentration, but it did shift the VFA profile to higher acetate, lower propionate and lower butyrate molar proportions, consistent with less $CH_4$ production by all microbial fractions.

• The Korean Journal of Nuclear Medicine
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• v.23 no.1
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• pp.7-12
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• 1989

The pain, swelling of salivary glands and dry mouth are not infrequent complication of the high dose radioiodine treatment in the patients with differentiated thyroid cancer. The purpose of this study was, by the dynamic salivary scintigraphy, to observe the change of the salivary function after the high dose $(150\sim200mci)$ radioiodine treatment. From May 1987 to April 1988, the dynamic salivary scintigraphy with 5mci of $^{99m}Tc-pertechnetate$ and gamma camera was performed before and 7 days after the radiolodine treatment in 7 patients with differentiated thyroid cancer. Just after the dynamic scintigraphy, the stimulation test with vitamin C solution of pH3.0 and poststirnulation scintigraphy were done, and the radioactivity uptake index, excretion fraction and salivary clearance after the stimulation were calculated for each gland. There was positive correlation between the radioactivity uptake index and excretion fraction after the stimulation. The salivary clearance after the stimulation was $18.96{\pm}8.95ml/min$ in the pretreatment state, and $14.37{\pm}7.7ml/min$ after the radioioine treatment. After the radioiodine treatment, the radioactivity uptake index, excretion fraction and salivary clearance after the stimulation were significantly reduced in the parotid glands, but only the excretion fraction was reduced in the submandibular glands. The more the pretreatment salivary clearance after the stimulation was, the % change after the treatment was smaller. Further studies on the relation between the radiation dose in the salivary glands and the change of their function, and the long-term observation for the recovery of function are expected.

• Fire Science and Engineering
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• v.19 no.2 s.58
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• pp.105-110
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• 2005

We tested the char characteristics of fire retardant treated Douglas fir at each of five constant external irradiance levels $(10,\;15,\;20,\;25\;및\;35kW/m^2)$. A Cone heater was used to expose the wood specimens to the heat flux. The size of specimens is 100- by 100- by 50-mm and the kinds of specimens are non-treated wood(N) and treated wood(F2 and f4) by water soluble fire retardants. The water-soluble fire retardants were made from mixture of aqueous solutions of monoammonium phosphate, sodium borate and zinc borate, and those are used for immersion of Douglas fir. In result of test, char fraction of fire retardant treated Douglas fir showed a considerably low char fraction than it of non-treated wood irrespective of increase of external heat flux. And char fractions has low levels with increase of fire retardant content. Burning rate of non-treated wood(N) was showed a relatively high burning rate than it of fire retardant treated wood(F2 and F4). And difference of burning rate shown more rapidly in high external irradiance than low external irradiance. When the external heat flux is $35kW/m^2$, average char rate of non-treated wood is rapidly about twice than fire retardant treated wood. Water-soluble fire retardants mixed in this study find out it has fire suppression and adiabatic effect by char layer from results of char fraction, burning rate, and char depth and rate.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.740-744
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• 1995

For the fabrication of a multi-pole anisotropic Sr-ferrite magnet by powder injection molding, it is important to control effectively the alignment of magnetic powders during the injection molding process. The effect of the fluidity of powder/binder mixture on the powder alignment was studied with changing the particle sizes and the volume fraction of Sr-ferrite magnetic powders. The critical volume fraction of Sr-ferrite powders increases from 58 vol.% to 64 vol.% as the mean powder size increases from $0.8\;\mu\textrm{m}$ to $1.2\;\mu\textrm{m}$. A Sr-ferrite powder alignment greater than 80 % is achieved at the conditions of an apparent viscosity lower than 1000 poise at $1600\;sec^{-1}$ shear rate, an applied magnetic field higher than 4 kOe, and a powder volume fraction 8 vol.% lower than the critical fraction. The powder alignment obtained during the injection molding process is not much affected by the subsequent processes of debinding and sintering, showing the magnetic properties of 3.8 kG of remanent flux density and 3.37 kOe of intrinsic coercivity.

• Korean Journal of Plant Resources
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• v.31 no.1
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• pp.16-23
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• 2018

Paeonia japonica is a perennial flowering plant used in traditional medicine therapy. The purpose of this study was to investigate the effect of water extract and solvent fractions obtained from P. japonica on anti-oxidative, anti-thrombin, anti-invasive and pro-apoptotic activities in YD-10B cells, human oral squamous carcinoma cell line. Water fraction revealed the highest extraction yield at 11.44% (w/w). Anti-oxidative activity was the highest in ethyl acetate fraction (85.13%). In the thrombin inhibitory activity test, ethyl fraction was the highest, with a value of 87.54%. Release and activation of MMP-2/pro-MMP-2 ratio in thrombin-treated YD-10B cells were significantly inhibited in the ethyl acetate fraction. At a concentration of $120{\mu}g/m{\ell}$ water extract and solvent fractions of P. japonica inhibited cell proliferation in YD-10B cells except water fraction. Pro-apoptotic effect on human oral squamous carcinoma cell using the Bax/Bcl-2 ratio analysis was higher in water extract than other fractions. These findings suggest that the ethyl acetate fraction of P. japonica potentiates a promising antioxidant, anti-thrombin and anti-invasive agents.