• Membrane Journal
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• v.6 no.4
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• pp.227-235
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• 1996

poly(acrylic acid)(PAA)-poly(vinyl alcohol)(PVA) membranes have been prepared by crosslinking reaction between the carboxylic acid groups of PAA and the hydroxylic groups of PVA. In the measurements of the swelling and preferential sorption of the membranes, sorption behaviors of the membranes in pure water, pure acetic acid and a mixture of them have been investigated, respectively. From the measurements of the preferential sorption in 90wt% acetic acid of aqueous mixture, the sorption of water component was found to be more enhanced at high PAA content in the membrane than that of acetic acid component due to the interaction of water with acetic acid. The sorption behavior and the degree of crosslinking influenced competitively the permeation behavior of permeants. Permeation behavior of perrecants through the membranes was analyzed by using permeation activation energies which had been obtained from the Arrhenius plots of fluxes.

• Membrane Journal
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• v.6 no.4
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• pp.250-257
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• 1996

Surface crosslinked chitosan composite membranes were prepared with glutaraldehyde and surfuric acid. Effects of neutralization for complex between chitosan and acetic acid and of water permeability for substrate membranes on pervaporation performance were investigated. For ionically crosskinked membranes, effect of active layer thickness on separation factor of water/ethanol mixture was studied. With increasing the water permeability of the substrate, the membrane showed an increased separation factor, while it maintained a constant permeate flux. Neutralized chitosan composite membranes revealed a decreased separation factor and a constant permeate flux. When the thickness of the active layer increased, an optimum crosslinking time to achieve higher separation factor shifted to a prolonged times.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.607-614
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• 2005

To determine the optimum fermentation condition, the 50:50 feed mixture of both crushed corn and wet brewer’s grain were anaerobically fermented at various conditions. Three supplementation levels(0, 2%, and 5%) of molasses, five supplementation levels(0, 0.1%, 0.5%, 1.0%, and 2.0%) of yeast and five different incubation temperatures(4$^{\circ}C$, 10$^{\circ}C$, 30$^{\circ}C$, 40$^{\circ}C$ and 50$^{\circ}C$) were tested to determine the optimum fermentation conditions. During fermentation, alcohol concentration, live yeast cell number (LYCN) and pH values of the mixture were analyzed. Alcohol concentrations of the fermented feed mixtures were proportionally increased with increasing level of molasses supplementation. After 24hr fermentation, alcohol concentrations at 0.1%, 0.5%, 1.0% and 2.0% of yeast supplementation was 1.9%, 2.4%, 3.1% and 3.1%, respectively. These results indicate a proportional increase of alcohol concentration with the increasing supplementation of yeast (P<0.05) up to 1%, thereafter showing plateau at 2% supplementation. LYCN was relatively high with more than 0.5% yeast supplementation, whereas the value was significantly low(P<0.05) at 0.1% yeast supplementation. Alcohol production was significantly higher at 30$^{\circ}C$ and 40$^{\circ}C$ than other incubation temperatures (P<0.05), with the highest concentration at 30$^{\circ}C$. pH was rapidly decreased until 24 hours of incubation with steeper decrease at lower temperatures(P<0.05). Based on there results, optimum fermentation conditions for the alcoholic-fermented feed production could be achieved with 5% supplementation of molasses, 1% supplementation of yeast, and 24hr long incubation at 30$^{\circ}C$.

• Journal of ILASS-Korea
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• v.19 no.3
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• pp.115-122
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• 2014

As a demand for an automobile increases, air pollution and a problem of the energy resources come to the fore in the world. Consequently, governments of every country established ordinances for green-house gas reduction and improvement of air pollution problem. Especially, as international oil price increases, engine using clean energy are being developed competitively with alternative transportation energy sources development policy as the center. Bio ethanol, one of the renewable energy produced from biomass, gained spotlight for transportation energy sources. Studies are in progress to improve fuel supply methods and combustion methods which are key features, one of the engine technologies. DI(Direct Injection), which can reduce fuel consumption rate by injecting fuel directly into the cylinder, is being studied for Green-house gas reduction and fuel economy enhancement at SI(Spark Ignition). GDI(Galoine Direct Injection) has an advantage to meet the regulations for fuel efficiency and $CO_2$ emissions. However it produces increased number of ultrafine particles, that yet received attention in the existing port-injection system, and NOX. As fuel is injected into the cylinder with high-pressure, a proper injection strategy is required by characteristics of a fuel. Especially, when alcohol type fuel is considered. In this study, we tried to get a base data bio-ethanol mixture in GDI, and combustion for optimization. We set fuel mixture rate and fuel injection pressure as parameters and took a picture with a high speed camera after gasoline-ethanol mixture fuel was injected into a constant volume combustion chamber. We figured out spraying characteristic according to parameters. Also, we determine combustion characteristics by measuring emissions and analyzing combustion.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.575-580
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• 2006

This Study was designed to investigate the effects of Mixture of Bambusae Caulis in Liquamen and Bamboo Extract on the change of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal and cerebral ischemic rats. Experimental materials were as follows ; BE- 1 was Bamboo Extract (BE) extracted with 70% ethyl alcohol, BE-11 was BE extracted with distilled water at $121^{\circ}C$ for 30 min, BE-111 was BE extracted with distilled water at $121^{\circ}C$ for 3 hrs, MLC was mixture of Bambusae Caulis in Liquamen (BCL) and BE-111 mixed at the ratio of 1 to 100 (MLC100), 1 to 50 (MLC50), 1 to 20 (MLC20), 1 to 10 (MLC10), 1 to 5 (MLC5). The results were as follows , The Changes of BE- 1 on the rCBF and MABP in normal rats were not showed, BE- 11 significantly decreased rCBF in a dose-dependent manner Dut increased MABP in a dose-dependent manner. BE-111 increased rCBF in a dose-dependent manner, MLC significantly increased rCBF in a dose-dependent manner and increased MABP in a dose-dependent manner. rCBF was significantly and stably increased by MLC5 (1 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. As results above ; The present author thought that BE- 111 and MLC increased rCBF by dilating pial arterial diameter.

• Korean Journal of Medicinal Crop Science
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• v.28 no.2
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• pp.128-135
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• 2020

Background: Sowing seeds of Adenophora triphylla is known to be difficult owing to their small size and irregular seed shape. Therefore, this study was conducted to develop a seed pelleting technique to save labor during sowing. Methods and Results: To identify the optimal germination temperature for A. triphylla seeds, the temperature range was set from 17℃ to 32℃. Germination surveys were conducted in plastic greenhouse conditions in March, April, and May to determine the appropriate sowing time. The optimal germination temperature for A. triphylla seeds was 29℃ and May was the optimal sowing time in plastic greenhouse conditions. Covering materials for seed pelleting used talc (T), kaolin (K), calcium carbonate (C), and vermiculite (V). The pellet binder used agar (A), pectin, xanthan gum, polyvinyl alcohol (PVA), and sodium alginate (S). The best suited treatment mixture were the best suited in kaolin / calcium carbonate / vermiculite (KCV), talc / calcium carbonate / vermiculite (TCV) mixture treatment for covering material, and sodium alginate (S), agar (A) as pellet binder, respectively. The germination rate was the best in TCV mixed with S. Conclusion: The mixture of TCV (2 : 1 : 3) + 1.5% S (TCVS), was found to be the best pelleting materials for A. triphylla seeds, and seed pelleting can be labor-saving during sowing.

• Transactions on Electrical and Electronic Materials
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• v.13 no.2
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• pp.89-92
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• 2012

The effect of organic impurities on the electrical properties of a neat epoxy resin was studied. 0.05, 0.5 and 1.0 phr of iso-propyl alcohol (IPA) and methylene chloride (MC) mixture (50/50 wt%) were used as impurities. The current density, volume resistance and impedance characteristics of the epoxy/IPA/MC systems were measured with a high voltage source meter and broadband dielectric spectroscopy. Glass transition temperature (Tg) was measured by a differential scanning calorimetry (DSC) and it was found that Tg decreased slightly with increasing IPA/MC content. It was also found that Tg values of the epoxy systems with various IPA/MC contents were closely related to the current density, volume resistance and impedance characteristics.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1741-1744
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• 2013

A new polymeric catalyst was prepared by supporting $GaCl_3$ on cross-linked polyvinylpyrrolidone ($GaCl_3$/PVP). This catalyst was employed for efficient and regioselective ring-opening reaction of epoxides by various alcohols under solvent-free conditions at room temperature. In our procedure, this heterogeneous catalyst was used at neutral and mild reaction conditions to afford high yields of ${\beta}$-alkoxy alcohols. Also, regioselective conversion of epoxides to ${\beta}$-azidohydrines was accomplished by sodium azide in MeOH in the presence of $GaCl_3$/PVP at room temperature. $GaCl_3$/PVP is a non-hygroscopic and recoverable catalyst and is easily separated from reaction mixture by a simple filtration and re-used repeatedly. Also, this catalyst has good handling and can be stored for long time without any reducing of its reactivity.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.2034-2040
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• 2020

The gas evolution from mixtures consisting of 0.2 M solution of N,N,N',N'-tetra-n-octyldiglycolamide (TODGA) in n-alcohol (n-decanol or n-nonanol) with Isopar-M diluent was investigated during thermal oxidation. The effect of ionizing radiation on their thermal stability has been studied. It has been determined that the volume of gaseous thermolysis products increases by 260% in the case of n-nonanol and 80% in the case of n-decanol compared to non-irradiated solutions. It has been shown that the gas evolution rate and gas volume increase when the irradiated mixture saturated with nitric acid is heated. However, there are no prerequisites for the development of autocatalytic oxidation.

• Transactions of Materials Processing
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• v.20 no.2
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• pp.173-178
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• 2011

Environmental Stress Cracking(ESC) is one of the most common causes of unexpected brittle failure of thermoplastic polymers. The exposure of polymers to liquid chemicals tends to accelerate the crazing process, initiating crazes at stresses that are much lower than the stress causing crazing in air. In this study, ESC of acrylonitirile butadiene styrene(ABS) was investigated as a function of the molding conditions such as injection velocity, packing pressure, and melt temperature. A constant strain was applied to the injection molded specimens through a 1.26% strain jig and a mixture of toluene and isopropyl alcohol was used as the liquid chemical. In order to examine the effects of the molding conditions on ESC, an experimental design method was adopted and it was found that the injection velocity was the dominant factor. In addition, predictions from numerical analyses were compared with the experimental results. It was found that the residual stress in the injection molded part was associated with the environmental stress cracking resistance (ESCR).