• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.271-271
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• 2006

The present article describes a novel method of preparing the sulfonated polysulfone-based PEMs for DMFC, which are excellent in film quality, proton conductivity, methanol impermeability and mechanical properties. No depression in film quality or difficulty in film preparation is observed, even though sulfonated group of the PEMs are kept as high as 70 mol %. Allyl-terminated cooligo-PESs containing the organic sulfonate groups were solvent-cast into films and then thermally treated for cross-linking. Cross-linked sulfonated polysulfone-based PEMs gave unprecedented reduction of methanol cross-over and high ionic conductivity through in-situ thermal polymerization and cross-linking of telechelic sulfonated sulfone oligomers during a membrane preparation.

• Journal of the Korean Dietetic Association
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• v.3 no.1
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• pp.23-29
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• 1997

This study was attempted to investigate changes in physiochemical properties of the preparation of saccharification kochujang with retrogradated cooked rice, bread, rice cake and sensory evaluation during 60days aging. 1. Moisture content in 4 samples were slowly increased and pH of kochujang was slowly decreased during aging. 2. Reducing sugar content were about 1.4~2 times higer than $T_3$ and $T_2$ at 50days of aging. 3. In no significant difference 4 samples, the level of adipic acid, citric acid, malic acid was the most and that of acetic acid, iso-butyric acid, fumaric acid, lactic acid, tartaric acid was smaller. 4. Sensory evaluation conducted by fifteen university students as panelist showed that their were more significant difference among four samples and notable preferance for $T_3$ over $T_0$, $T_1$, $T_2$.

• Journal of the Korean Ceramic Society
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• v.47 no.2
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• pp.177-182
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• 2010

To synthesize $Gd_2O_3:Eu^{3+}$ phosphor, gadolinium-europium oxalate precursors were prepared from oxalic acid, NaOH or aqueous ammonia via coprecipitation method. The obtained precursors were heat-treated and then characterized by XRD, SEM and PL. The kinds and amounts of coprecipitant (NaOH or aqueous ammonia) were found to affect the powder morphology and properties of gadolinium-europium oxalate precursors. Two crystalline precursors and one amorphous precursor were synthesized. The nanometer-sized amorphous gadolinium-europium oxalate precursor was first prepared using the oxalate coprecipitation technique. The calcined powders obtained from the amorphous precursor were nearly spherical in shape, and a narrow size distribution was obtained. The NaOH coprecipitant was more effective in the preparation of nanometer-sized spherical powders. A thermal decomposition process was conducted for the three kinds of precursors. The photoluminescence property was also measured as a function of europium content, and concentration quenching occurred for samples with europium concentrations of over 10 mol%.

• Journal of Hydrogen and New Energy
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• v.4 no.2
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• pp.23-28
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• 1993

The $(LM)Ni_{4.5}Co_{0.1}Mn_{0.2}Al_{0.2}$ hydrogen storage alloy powders were conducted 25wt% electroless copper plating in an acidic bath. For the preparation of a hydride electrodes, the copper coated alloy powder was mixed with Si-sealant(organosilicon) and compacted with $6t/cm^2$ at room temperature. The electrode characteristics were examined through electrochemical measurements in a half cell. As a sealant contents increased, the initial discharge capacity of si-sealant bounded electrode was lower and the activation rate in high current density was slower. For extended cycles, however, the electrodes with the Si-sealant were superior in a high rate discharge and useful range of temperature over the sealant-free electrode. In addition, the cycle life increased with increasing the amount of Si-sealant added. It can be suggested from the results that the Si-sealant as a binder could be applied to the preparation of the metal hydride electrode.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.281-289
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• 2010

This study was performed to provide basic data on sous-vided beef sirloin by comparing its water content, color, brightness, number of microorganism, mechanical quality characteristic test, and sensory test with a control group that was cooked using a traditional preparation method. There were no significant pH difference but water content, brightness, yellowness, and springiness were higher for the sous-vided beef sirloin, however, the sous-vided beef sirloin had less redness, hardness, and number of microorganism. Although sous-vided beef sirloin required a longer cooking time, it was softer and had a higher springiness. Generally, the sous-vided beef sirloin had a showed longer storage period and better evaluation than traditionally cooked beef sirloin in the sensory test. As a result, sous-vided beef sirloin is expected to have several merits over traditional preparation methods.

• The Korean Journal of Food And Nutrition
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• v.4 no.1
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• pp.91-98
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• 1991

This study was carried out to investigate the effect of the emulsion stability according to the quantity of emulsifiers and the pressure of homogenizer in coffee whitener preparation. The results of this study are as follow : 1. To obtain a standard emulsifier, the ratio of mono and triglycerides(Atoms 150), sorbitan monostearate (Span 60) and polyoxylene(20) sorbitan monostearate(Tween 60) was 60 . 20 : 20 and the optimum quantity was about 0.9fS for stable emulsion. 2. Characteristics as coffee whitner were markedly improved when the pressure of homogenizer was 200∼250kg1cmz and homogenizing times are over 4. 3. The good whitening capacity was showed when fat glouble's average diameter was under 0.5 Um.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.2
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• pp.45-49
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• 1994

The rapid preparaton method of soybean curd with ultra fine soy powder at home was investigated. The microwave oven of this study used common microwave attached sensor for the volume and temperature control, The temperature of the microwave oven was maintained at 98, not boiling over. It took 9 minutes to make 300g of soybean curd, 10 minutes to make 600g, 14 minutes to make 900g, and 17 minutes to make 1200g. Beany flavor and trypsin inhibitor could be removed by this conditon. It took only 5 min to make coaguation of the curd by glucono-$\delta$-lactone.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3745-3748
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• 2012

This study presents a rapid and simple ${\alpha}$ source preparation method for a radioactive waste sample. The recovery of $^{239}Pu$, $^{232}U$ and $^{243}Am$ using a micro-coprecipitation method was over 95%. The ${\alpha}$-peak resolution of Pu and Am isotopes through the micro-coprecipitation method is enough to discriminate the Pu and Am isotopes from other Pu and Am isotopes. The determination of the Pu and Am isotopes using the micro-coprecipitation method was applied to the radioactive waste sample, so that the activity concentrations of the Pu and Am isotopes using the micro-coprecipitation method in the radioactive waste sample were similar to those using the electrodeposition method.

• YAKHAK HOEJI
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• v.47 no.6
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• pp.352-355
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• 2003

Voglibose is a new antidiabetic agent currently being devoloped by the research and development division of Takeda chemical industries Ltd. in japan. Basic research for the determination of voglibose in pharmaceutical preparation by gas chromatography. This method utilizes voglibose to give its acyl compound with acetyl anhydride in pyridine solution. The calibration curve for voglibose was linear over the concentration range of 0.08∼0.32 $\mu\textrm{g}$/${mu}ell$ with correlation coefficient of 0.996. The detection limit for voglibose was 0.016 $\mu\textrm{g}$/${mu}ell$ and the result of recovery test was 101.6% with relative standard deviation of 2.0% by standard addition method.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.1
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• pp.11-21
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• 2018

This study examined which influence the pre-entrepreneurs' individual norm and start-up preparation level have upon a start-up intention, and analyzed a moderating effect in start-up education as for a relationship of individual norm and start-up preparation level with a start-up intention. For the purpose of offering useful data so that the pre-entrepreneurs of planning start-up can do more successful start-up through this, it carried out questionnaire from September 13, 2017 to November 14, 2017 targeting pre-entrepreneurs who received start-up education at an educational institution and a university that are located in K region. As a result, excluding 11 copies with a difficulty in the application to statistics among totally 211 copies, 200 copies were chosen as the final samples. Data were conducted reliability analysis, factor analysis, correlation analysis and regression analysis by using SPSS 20.0. The results are as follows. First, the individual norm had a significant impact on a start-up intention. Second, the start-up preparation level had a significant effect on a start-up intention. Third, the start-up education had a moderating impact in the relationship between the individual norm and the start-up intention. Fourth, the start-up education had a moderating influence in the relationship between the start-up preparation level and the start-up intention. However, this study limited the sampling region to K area, thereby having a limitation in generalizing the findings all over the country. Moreover, there is a suggestion that a continuous research will need to be performed in terms of an influential factor in pre-entrepreneurs' start-up intention as well as in individual norm and start-up preparation level.