• Journal of the Korean Ceramic Society
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• v.43 no.7 s.290
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• pp.427-432
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• 2006

The preparation of SiC powder by SHS in the system of $SiO_2-Mg-C$ was investigated in this study. The effects of various processing parameters such as the initial pressure of inert gas in reactor, the content of Mg and C in mixture and the size of $SiO_2$ particles on the synthesis of SiC by SHS methode were investigated. The minimum initial pressure of inert gas in reactor for SHS reaction in this system was 5 atm, and as the pressure increased, and the concentration of unreacted Mg decreased. At 50 atm of the initial inert gas pressure in reactor, the optimum composition for the preparation of pure SiC was $SiO_2+2.5Mg+1.2C$. SiC powder synthesized in this condition had a mixture of ${\alpha}-SiC\;and\;{\beta}-SiC$ with an irregular shape and the particle size of $0.5{\sim}0.8{\mu}m$.

• Journal of Korean Home Economics Education Association
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• v.11 no.1
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• pp.25-45
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• 1999

Home economics is a very important part of high school curriculum. The goal of home economics is to enable the students to get necessary knowledge and skills of household affaires, so they can manage their household tasks easily. This study was investigated to know the present condition of high school food preparation classes and evaluation method and to find out the problems related to the evaluation. Ninety four teachers from Kyoung-Ki province answered the questionnaire. The results are as follows： They though that the most appropriate food preparation classes should be at least 4-6 in a year. But in practice they only had 1-2 classes because of the time and budget. Because most of the teachers wanted the students to apply their knowledge to real life, they mainly chose Korean foods instead of western foods. It may help the students understand the Korean traditional food. Most of the schools needed additional gas oven ranges, microwave ovens and water purifiers. Most teachers(87.50%) evaluated the students in groups. This was due to limited time and lack of objective evaluation methods. So it is suggested that the Ministry of Education must make the measure of objective evaluation and allot more home economics hours at high school curriculum.

• Journal of the Korean Society of Food Culture
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• v.10 no.5
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• pp.457-463
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• 1995

This study was undertaken to investigate the knowledge and the use of Korea traditional basic side dishes, Jangachies, by housewives. Among the 58 kinds Jangachies, the most well-known Jangachies (above 80% of subjects) turned out to be Perilla leaf, Red pepper leaf, Garlic, Young stem of garlic, Green red leaf, Cucumber and dried Radish Jangachi in the order. In cooking experience of Jangachi, 40% of subjects in Perilla leaf, 28.0% in Green red pepper, 24.8% in Garlic and 24.1% in Red pepper leaf Jangachi have cooked frequently. The proportion of subjests who has bought the marketed Jangachi products were 51.6%. Major problem of that products was pointed out for a sanitary condition, high price and poor taste. If marketed Jangachies were improved over the aspects, the proportion of subjects who would buy the products was 76.2%. The frequency of Jangachi intake was very low on a average due to too salty taste and the difficulty in preparation. The older in age, the more in interest level for Jangachi (p<0.05). 39.6% of subject have had preparation ability of Jangachies. With increasing age (p<0.01), decreasing education level (p<0.01) and those who live in rural area (p<0.05), preparation ability of Jangachi tended to be higher.

• Journal of the Korea Convergence Society
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• v.3 no.2
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• pp.27-32
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• 2012

The purpose of this study was to find out the effect of self-efficacy, career decision-making styles, and career decision-making level of the college the department of Dental Hygiene 1,2,3 students. The subjects of this study were 106 university students of the department of Dental Hygiene in K university. The instrument employed were the Career Decision Making Self Efficacy Scale, career decision level, career preparation behavior.The data collected were analyzed using Frequency analysis, t-test, Regression analysis and the pearson correlation of the spss 19.0 version.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.13-17
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• 2012

In order to enzymatically produce chitooligosaccharide using the crude enzyme preparation from Bacillus cereus D-11, we first studied the optimal reaction conditions. It was found that the optimal temperature for hydrolysis of chitosan was $55^{\circ}C$. The ratio of enzyme/substrate should not be lower than 0.13 U/mg in the reaction mixture. The enzyme activity was stable below $50^{\circ}C$. The products of enzymatic reaction were analyzed by both thin layer chromatography and high performance liquid chromatography. Under the appropriate condition, chitosan was hydrolyzed using the enzyme preparation. The resulting chitooligosaccharides were purified and separated by Dowex ($H^+$) ion exchange chromatography. From 4 g soluble chitosan, 0.95 g $(GlcN)_2$, 1.43 g $(GlcN)_3$, and 1.18 g $(GlcN)_4$ were recovered.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.71-76
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• 2011

An efficient nucleophilic [$^{18}F$]fluorination has been studied to reduce byproducts and preparation time. Instead of conventional aqueous solution of $K_2CO_3-K_{222}$, several organic solution containing inert organic salts were used to release [$^{18}F$]fluoride ion and anion bases captured in the polymer cartridge, concluding that methanol solution is the best choice. Comparing to azeotropic drying process, one min was sufficient to remove methanol completely, resulting in about 10% radioactivity saving by reducing drying time. The polymer cartridge, Chromafix$^{(R)}$ (PS-$HCO_3$) was pretreated with several anion bases to displace pre-loaded bicarbonate base. Phosphate bases showed better results than carbonate bases in terms of lower basicity. tert-Butanol solvent used as a reaction media played another critical role in nucleophilic [18F]fluorination by suppressing eliminated side product. Consequent [$^{18}F$]fluorination under the present condition afforded fast preparation of reaction solution and high radiochemical yields (98% radio-TLC, 84% RCY) with 94% of precursor remained.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.51-57
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• 1999

In this study, one side fillet welded T-joint, used in box type girder and other welding structure, was investigated by stress analysis and bending fatigue test without edge preparation, with variation of joint shape. The purpose of this study is to give the welding condiltion and design standard on manufacturing one side fillet welded T-joint. As a result, the following conclusions were obtained. 1) In one side fillet welded T-joint, the larger the leg length and the penetration depth, the greater the bending fatigue strength because reduction of stress and strain on toe and root. The increase of the longitudinal leg length rather than vertical leg length contributed to the increase in bending fatigue strength. 2) In one side fillet welded T-joint without edge preparation, both general manual welding and general automatic welding were carried out with same condition. In this case, automatic welding showed deeper penetration and more increased longitudinal leg length than manual welding, so that automatic welding offers greater bending fatigue strength. 3) For one side fillet welded T-joint without edge preparation with automatic welding, the ratio(h/t) of the leg length(h) and the main plate thickness(t) in which toe crake can occur was 1.0 over.

• Journal of Pharmaceutical Investigation
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• v.34 no.2
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• pp.125-130
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• 2004

Paclitaxel is an effective antineoplastic drug for various cancers especially ovarian and breast cancer. This study is to find the optimum condition for the preparation of nanoemulsions and to improve the stability and loading amount of paclitaxel in nanoemulsions. Nanoemulsions were prepared by modified spontaneous emulsification solvent diffusion method. It was composed of phosphatidylcholine:cholesterol:1,2-Distearoyl-sn-Glycero-3-Phosphoethanolamine-N-[Metoxy (Polyethylene glycol)-2000]:paclitaxel at a weight ratio of 5:3:1:1 and the Tween 80 as a surfactant. The particle size and the shape of nanoemulsions were measured by particle analyzer and SEM, respectively. The loading amount of paclitaxel in nanoemulsion was measured by UV-visible spectroscopy at 227 nm. The particle sizes were $80{\sim}120\;nm$ and the loading efficiency of paclitaxel was $8{\sim}39%$. The optimum conditions for the preparation of nanoemulsions were 8% w/w phospholipid, 16% w/v Tween 80 and 2% w/w paclitaxel, respectively.

• Applied Microscopy
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• v.23 no.2
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• pp.1-10
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• 1993

The effect of electrolyte on the extraction replicas of the precipiates in 3% Si steel was investigated. Three Kinds of electrolyte, 2% Nital solution (2% nitric acid+methanol; acid solution),, Sodium Citrate solution (5% sodiumcitrate+1% KBr+0.5KI+$H_{2}O$; aqueous neutral solution) and 10% AA solution (10% acetylacetone+ 1% tetramethylammoniumchloride+methanol; non-aqueous neutral solution), were compared. The preciptiates in 3% Si steel were dissolved in 2% Nital, but they were not dissolved in the Sodium Citrate and 10% AA solution. In Sodium Citrate solution, however, large second artifacts were introduced during sample preparation. Therefore 10% AA solution was found to be most useful for the preparation of extraction replica. The electrolysis condition of a matrix and precipitates were also checked by the measurement of potential-current curve in 10% AA solution. The matrix was electrolyzed at -400mV with respect to SCE(Saturated Calomel Electrode). In contrats precipitates were electrolyzed above 300mV. Precipitates were respected to be stable in 10% AA solution in the range of $-380mV{\sim}-300mV$ usually used to prepare extraction replicas.

• Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.8-11
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• 1999

The optimum boiling condition was determined for fish extracts by response surface model. Model equations were designed with effect of time (T) and the amount of added water (W) on the level of released free amino acid. Based on the high (>0.9) coefficient of determination and low (<0.01) level of significant, those model was approved to be significant. The added water amount of higher regression coefficient $ (\beta_2)$, showed a greater influence on releasing free amino acids than boiling time. The optimum boiling times are 6 hours for crucian carp, 5 hours for bastard halibut, 7 hours for loach and 5 hours for jacopever. The ratio of added water to sample 1 (v/w) could be applied to all fish samples at $100\pm2^{\circ}C$.