• Journal of Ginseng Research
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• v.14 no.3
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• pp.379-384
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• 1990

In order to study the lipid peroxidation caused by light and the protective action it in biological memberane, reverse-phase evaporation liposome (REV) was employed as a model memberance and the effect of several antioxidants and ginseng water extracts were tested. In the presence of photosensitizer, liposome was oxidized easily and the oxidation index dut to the peroxidation was increased. The oxidation index of liposome was increased according to the increase in temperature. When dl-${\alpha}$-tocopherol, ${\beta}$-carotene or L-ascorbic acid was added into the reaction mixture, the photooxidation of liposome was inhibited. Ginseng water extract and crude saponin inhibited the rate of oxidation index of liposome in low concentration but increase in high concentration. On the other hand, when lipid hydroperoxide of liposome was tested by ferrothiocyanate method, ginseng water extract and crude saponin acted as antioxidants.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.9_10
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• pp.1153-1159
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• 2003

The effects of changing aqueous solution properties by nonionic surfactants on wetting behavior and water retention properies of hydrophobic PET (polyethylene terephthalate) fabric were reported. The aqueous solution properties were diversified by mixing and diluting two nonionic surfactants, i.e., sorbitan monolaurate (Span 20) and polyoxyethylene(20) sorbitan monolaurate (Tween 20). The surface wetting properties ($cos{\theta}$) of PET fabric were greatly improved by adding $10^{-1}g/dl$ Tween 20 and further improved by mixing Span 20 to the system. The water retention properties (W) of PET fabric were also greatly increased by addition of $10^{-1}g/dl$ Tween 20. In diluted surfactant systems, the $cos{\theta}'s$ were increased with decreasing surface tension of aqueous liquids. The ratios of aqueous liquid retained in the pore structure to liquid retention capacity (W/H) were also increased with decreasing surface tension, however, W/H values were dramatically increased right after critical micelle concentration (cmc). The existence of micelles was important for the retention of aqueous liquids in the fabric. The critical surface tension of PET fabric used was found to be 28.7dyne/cm.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.3
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• pp.267-276
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• 2000

A numerical study has been carried out to find out the optimal design condition of a solar absorption cooling system. The system was composed of solar collectors and an absorption chiller with LiBr/water The System performance with commercial single effect(SE) cycle and a new single effect/double lift(SE/DL) cycle utilizing low temperature hot water was calculated and compared. It was found that the required solar collector area grew exponentially as the overall heat loss coefficient of solar collectors increased. For instance, the required area for cooling capacity of 1 USRT was $17m^2$ if heat loss coefficient was 4 W/$m^2\;cdot\;K$. If heat loss coefficient was doubled($8\;W/m^2\;cdot\;$K), the required collector area was increased by 6 times($100m^2$) .It was also found that the SE-cycle as the heat loss coefficient of solar collectors increased. Generally, a SE/DL-cycle seems to be more advantageous than a SE-cycle if loss coefficient of solar collector is greater than 4 W/$m^2\;cdot\;K$.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.3
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• pp.37-44
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• 2000

The corrosion behavior of aluminum pad coated with epoxy molding compound (EMC) was investigated using electrochemical impedance spectroscopy (EIS). The impedance change was evaluated by the absorption of deionized water (DI water) to EMC coating and the interface between EMC and aluminum. During the absorption a decrease in resistance and thus an increase in capacitance of EMC as well as the interface of EMC/Al could be observed. Up to about 170 hours of absorption the EMC was saturated with the water molecules and ions generated from EMC. Subsequently the ionic water was penetrated to the interface and finally the corrosion of aluminum was occurred by the Dl water and ions. From measuring the adhesion strength with the Dl water absorption it was expected that the saturation of water and ions in the interface decreased the adhesion strength. The higher filler content of EMC should be necessary to inhibit the corrosion of aluminum electrode in microelectronic packages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.487-491
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• 1995

Effects of pH and molecular weight on the intrinsic viscosity of carboxymethyl chitin (CM-chitin) in dilute regime were studied. When the prepared CM-chitin was dissolved in 0.1M NaCl solution at $30^{\circ}C$, the intrinsic viscosity, molecular weight and degree of substitution of CM-chitin were 1.23dl/g, 15,500 and 0.62, respectively. The lower intrinsic viscosity $([\eta])$ of CM-chitin was showed at the lower pH than 7.0 and the higher pH (>7.0) did not result in any increase in intrinsic viscosity. Intrinsic viscosity decreased from 3.1dl/g to 2.55d1/g in water at $25^{\circ}C$ and from 15,500 to 12,600 as molecular weight for 20min of sonication treatment. The Mark-Houwink constant K and v of CM-chitin in water at $25^{\circ}C$ were $3.48\times10^-4$ and 0.94, respectively. So intrinsic viscosity could be expressed using molecular weight as followed equation; $[\eta]=3.48\times10^{-4}M^{0.94}$, consistent with random roil behaviour.

• Journal of Ginseng Research
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• v.26 no.4
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• pp.173-177
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• 2002

We examined effects of red ginseng on the formation of glycated protein in vivo and in vitro. The mixtures (1 : 1 : 1, v/v/v) with glucose (1.5 g/dl, hemoglobin (10 g/d) and red ginseng extract (0.5 g/dl) in 0.067 M phosphate saline buffer were incubated for 5 days in shaking water bath (37$\^{C}$, 70 RPM). Male rats were divided into three groups with one health and two diabetes, consisting of 20 heads in each group. Diabetic rats, induced by streptozotocin injection, were treated with or without red ginseng extract (100 mg/kg/day) for 3 months. The concentration of blood glucose and the rate of glycated hemoglobin were determined by commercial kits. The rate of glycated hemoglobin was significantly decreased by the addition of ginseng extract in comparison with non-addition group in vitro (12.17$\pm$ 1.01% vs 15.9$\pm$ 1.95%, meansd, p<0.01). Even though the levels of blood glucose in rats were not significantly different from each other, the rate of glycated hemoglobin in ginseng treated diabetic rats was $\pm$ se significantly lower than non-treated diabetic rats after 3 months (15.1$\pm$ 2.06% vs 20.1 $\pm$ 2.9%, mean$\pm$ sd, p<0.05). Additionally, the body weight was increased, drinking water volume was decreased non-significantly by the treatment of ginseng extract. These results suggest that ginseng can also inhibit the formation of glycated protein by other mechanisms which are not related with hyoglyemic effect of ginseng.

• Journal of Korea Water Resources Association
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• v.34 no.4
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• pp.357-364
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• 2001

Sometimes the observed data is too small to discriminate it from noise of the instrument. Say, the data can be recorded as below DL(Detection Level) value. Even though the data below Detection Level(BDL) is small vague, it can be resulted in wrong estimates for mean and variance. However, in practice, the BDL data is generally eliminated as N.D. (Not Detected) and do not record it in Korea. This study investigates the distributions according to the data values of ammonia concentration (NH$_3$-N) in Puyeo intake. Also we try to find out DL value and an appropriate method for the estimations of mean and variance of BDL values that can be discriminate the distributions. The DL is estimated by trial and error method. The appropriate method for the estimations of mean and variance of above the detection level(ADL)and BDL dada sets is selected, and the mean and variance are estimated. As a result, it is found that the Bias Corrected Maximum Likelihood Estimator is the most accurate method for NH$_3$-N in Puyeo intake.

• Korean Journal of Veterinary Research
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• v.60 no.4
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• pp.209-213
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• 2020

This study examined the residue of dl-methylephedrine hydrochloride (MEP) on the muscle of pigs administered orally with MEP 12 g/ton feed for seven consecutive days. Twenty healthy cross swine were administered MEP. Four treated animals were selected arbitrarily to be sacrificed at 1, 2, 3, 4, and 5 days after treatment. MEP residue concentrations in the muscle were determined by liquid chromatography coupled with tandem mass spectrometry. The drug was extracted from muscle samples using 10 mM ammonium formate in acetonitrile followed by clean-up with n-hexane. The analyte was separated on an XBridgeTM hydrophilic interaction liquid chromatography column using 10 mM ammonium formate in deionized distilled water and acetonitrile. The correlation coefficient (R2) of the calibration curve was 0.9974, and the limits of detection and quantification were 0.05 and 0.15 ㎍/kg, respectively. The recoveries at three spiking levels were 94.5-101.2%, and the relative Standard Deviations was less than 4.06%. In the MEP-treated group, MEP residues on one day post-treatment were below the maximum residue limit in the muscle. The developed method is sensitive and reliable for the detection of MEP in porcine muscle tissues. Furthermore, it exhibits low quantification limits for animal-derived food products destined for human consumption.

• The Journal of Advanced Prosthodontics
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• v.16 no.2
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• pp.105-114
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• 2024

PURPOSE. This study aimed to evaluate the effect of pretreatment of three different universal adhesives (Single Bond Universal [SBU], All-Bond Universal [ABU], and Prime&Bond universal [PBU]) on the bonding durability of an adhesive (Panavia F 2.0, PF) and a conventional (Duo-Link, DL) resin cements to air-abraded zirconia. MATERIALS AND METHODS. Rectangular-shaped zirconia specimens were prepared. The chemical composition and surface energy parameters of the materials were studied by Fourier transform infrared spectroscopy and contact angle measurement, respectively. To evaluate resin bonding to the zirconia, all the bonding specimens were immersed in water for 24 h and the specimens to be aged were additionally thermocycled 10000 times before the shear bond strength (SBS) test. RESULTS. The materials showed different surface energy parameters, including the degree of hydrophilicity/hydrophobicity. While the DL/CON (no pretreatment) showed the lowest SBS and a significant decrease in the value after thermocycling (P < .001), the PF/CON obtained a higher SBS value than the DL/CON (P < .001) and no decrease even after thermocycling (P = .839). When the universal adhesives were used with DL, their SBS values were higher than the CON (P < .05), but the trend was adhesive-specific. In conjunction with PF, the PF/SBU produced the highest SBS followed by the PF/ABU (P = .002), showing no significant decrease after thermocycling (P > .05). The initial SBS of the PF/PBU was similar to the PF/CON (P = .999), but the value decreased after thermocycling (P < .001). CONCLUSION. The universal adhesive pretreatment did not necessarily show a synergistic effect on the bonding performance of an adhesive resin cement, whereas the pretreatment was beneficial to bond strength and durability of a conventional resin cement.

• Journal of Convergence for Information Technology
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• v.9 no.5
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• pp.40-47
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• 2019

The purpose of this study aimed to develop the misutkaru water drink intake program that was possible to compare the effects of misutkaru drink on relieving constipation and physiological measurementson relieving constipation of the patients with hemodialysis. This study was non-equivalent control group pretest-posttest design with 42 patients in a general hospital in S city, Korea. During the experiment, the participants had to drink misutkaru water in the morning and past the 7 days after intake as constipation assessment scale, potassium and phosphorus were measured. The data were examine using t-test, Fisher's exact test, paired t-test. After misutkaru drinking intervention, constipation (z=-2.66, p=.002) decreased significantly improvement. This suggests that misutkaru water drinking intervention improved constipation in patients with hemodialysis.