• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.12 no.1
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• pp.1-10
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• 1999

In this paper, we have investigated the effects of the environmental factors on Low Molecular Weight (LMW) silicone fluid contents existing in high temperature vulcanized (HTV) silicone rubber sample, using dipping method and contact angle, current measurement. Artificial treatments such as immersion in water, elevated temperature, UV irradiation and dry band arcing under salt-fog condition are selected as the environmental factors. This results will be helpful to investigate the degradation with time and to expect a life time, because the LMW silicone content, which is important to recovery the hydrophobicity of silicone rubber surface, show different results by each environmental factors.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.5
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• pp.327-333
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• 2008

The purpose of this study is to develop a paddle-type dryer and to commercialize the dryer, in which mixing and drying can be done simultaneously. According to a performance test, a newly-designed paddle-type dryer can dry Chitosan salt to a low moisture contents below 0.3%. Also the newly-designed dryer can dry air pollution materials, because the dryer can operate in a closed system. The economic efficiency of a newly-designed system and an existing system was compared in a performance test. As a result, the economic efficiency of a newly-designed system was higher than an existing system. In conclusion, it is thought that the newly-designed system has a high commercial value.

• Journal of the Korean Society of Food Culture
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• v.16 no.3
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• pp.260-267
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• 2001

This study was conducted to investigate the physicochemical characteristics of Sunchang traditional kochujang(fermented hot pepper-soy bean paste) for quality standardization. The kochujang samples, which have been fermented for 8 months in 1999, were collected from 20 firms at folk village in Sunchang area and analyzed their chemical compositions and color reference. The mean value of moisture, amino-type nitrogen, pH, acidity and salt content of the samples collected were $44.62{\pm}1.79%$, $132.66{\pm}21.67\;mg%$, $4.52{\pm}0.08$, $15.77{\pm}1.62$ and $8.76{\pm}1.55%$, respectively. The moisture, pH, acidity and salt content of each sample did not show much differences among samples. The Hunter values(L, a and b) of Sunchang traditional kochujang were $25.72{\pm}1.58$, $23.26{\pm}1.71$ and $9.86{\pm}0.94$, respectively. The mean content of amino-type nitrogen of Sunchang traditional kochujang was $132.66{\pm}21.67\;mg%$, and there were a little difference between the minimum(100.33 mg%) and the maximum(164.56 mg%). The main free sugars of Sunchang traditional kochujang were fructose($1.86{\pm}1.01%$), dextrose($4.29{\pm}2.06%$), sucrose($0.54{\pm}1.21%$), and maltose($1.48{\pm}0.77%$). The contents of fructose, dextrose, and maltose had little difference among samples. The fatty acids in Sunchang traditional kochujang were composed of palmitic, stearic, oleic, linoleic, linolenic, octadecatetraenoic, arachidonic and behenic acid. The linoleic acid(18:2) showed the highest, occuping 59.37% of the total fatty acids.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.91-97
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• 2008

Kimchi is a representative traditional food in Korea and a type of vegetable product that is the unique complex lactic acid fermentation in the world. It can be considered as a unique fermented food generated by various flavors, which are not included in raw materials, that can be generated by mixing and fermenting various spices and seasonings, such as red pepper powder, garlic, ginger, and salted fish, added to Chinese cabbages. Functionalities in Kimchi have been approved through several studies and the probiotic function that is mainly based on lactic acid bacteria including their physical functions in its contents has also verified. Studies on the verification of the safety of Kimchi including its physiological functions have been conducted. In particular, the function of lactic acid bacteria, which is a caused of the fermentation of Kimchi. Although the lactic acid bacteria contributed to the fermentation of Kimchi is generated from raw and sub-materials, the lactic acid bacteria attached on Chinese cabbages has a major role in the process in which the fermentation temperature and dominant bacteria are also related to the process. The salt used in a salt pickling process inhibits the growth of the putrefactive and food poisoning bacteria included in the fermentation process of Kimchi and of other bacteria except for such lactic acid bacteria due to the lactic acid and several antimicrobial substances generated in the fermentation process, such as bacteriocin and hydrogen peroxide. In addition, the carbon dioxide gas caused by heterolactic acid bacteria contributes to the inhibition of aerobic bacteria. Furthermore, special ingredients included in sub-materials, such as garlic, ginger, and red pepper powder, contribute to the inhibition of putrefactive and food poisoning bacteria. The induction of the change in the intestinal bacteria as taking Kimchi have already verified. In conclusion, Kimchi has been approved as a safety food due to the fact that the inhibition of food poisoning bacteria occurs in the fermentation process of Kimchi and the extinction of such bacteria.

• Korean journal of food and cookery science
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• v.13 no.2
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• pp.92-98
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• 1997

Ethyl carbamate is an animal carcinogen and a by-product of fermentation. Since the highest level of ethyl carbamate was found in a traditional soy sauce sample in the previous study, soysauce was prepared in varying experimental conditions with three kinds of meju originated from different area of the country to investigate the factors affecting ethyl carbamate formation. The sample analysis methods included a semi-purification with solid-phase extraction and detection by GC-MS at SIM mode using m/z 62 fragment ion. Among the investigated factors, which includes source meju, bringing length, salt content, irradiation of visible light during bringing or storage, and storage length, source meju and storage length showed most profound effect on the formation of ethyl carbamate. Irradiation of visible light for 12 hours a day during storage lowered the concentration of ethyl carbamate compared to the soysauce kept in the dark. Meanwhile irradiation during the bringing as well as the degree of salt contents showed no effect.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.215-220
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• 1989

For development of slow releaseing K-fertilizer using natural zeolite, two kinds of K adsorbed zeolite were made by ion exchange reaction in $K^+$ saturated aqueous solution. K-Zeolite was prepared by removing the excess salt after K adsorption on zeolite, however, NW. K-Zeolite was prepared only by K adsorption reaction without removing the excess salt. The adsorbed K on zeolite was not easily released, but continuously and slowly released from the surface of zeolite. By the results of application for tobacco cultivation, the K contents in soil treated with K-Zeolite and NW. K-Zeolite were lower than that of control (20kg/10a) at the early growth stage, but were higher at the late growth stage. Therefore, the results suggest that K adsorbed zeolite could be applied as a slow-releasing K fertilizer.

• Journal of the Korean Society of Food Culture
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• v.8 no.3
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• pp.257-266
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• 1993

The purpose of this study was to develop a computer-assisted patients menu planning program for hospital dietetics in order to improve the quality of menu for patients and to release managers from repetitive and routine tasks. Using this program, dietitians can spend more time on professional tasks. Moreover, few studies have been done on computer assisted patients menu planning for patients who need special diets for treatment in domestic hospital dietetics, therefore this program could be a great contribution. A 16-bit personal computer compatible with IBM-PC/AT was used. The data base files and processing program were created by Clipper package ver 5.0. This system can collect a number of meals, plan patients menu and computerize nutrient analysis. The future study will develop program(s) for purchasing, inventory control and data correction. The contents of computerized system are summarized as follows. 1. The number of daily meals of special and general diets given to the patients are collected and saved in database. These data were for the monthly list of meal census which could be printed out on the screen and/or the printer. 2. The menu planning was largely consisted of 2 sections. One was for the patients who require special diets and the other was general diet. And the special diets was divided into 6 sub-sections: diabetic, low-salt, low-fat, low-salt/low-protein, low-fat/low-cholesterol and low residue diets. 3. The nutrient analysis was composed of 11 diet. Sections and diebetic diet was divided into 9 sub-sections according to the calorie requirement. The calculated results were compared with the standards which were established by the hospital dietetic department.

• Journal of the Korean Applied Science and Technology
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• v.13 no.2
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• pp.85-92
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• 1996

Chitosan itself has been prepared using chitin, one of the most abundant compounds in nature, as a starting material. We have synthesized the water-soluble chitosan derivative, N-dithiocarboxy chitosan sodium salt, through the reaction of water-soluble chitosan with carbon disulfide in the presence of alkali metal hydroxide. To elucidate this natural polymer capacity of adsorbing heavy metal ions, we have performed adsorption experiments using the water-soluble chitosan derivative various average molecular weight and of different percent contents of sulfur. The effect of pH, adsorption time and temperature on adsorption efficiency was also studied. The adsorbent derived from water-soluble chitosan of average molecular weight ranging $9,000{\sim}120,000$ was shown to have the highest capacity of adsorbing heavy metal ions. On the whole, adsorbing efficiency was increased as the reaction time goes longer and also increased as the reaction temperture goes higer in temperture range of $15^{\circ}C{\sim}45^{\circ}C$. The adsorption capacity at various pH, however, was appeared to vary depending on the heavy metal ions studied Judging from these finding, water-soluble N-dithiocarboxy chitosan sodium salt, a derivative of a biodegradable nature polymer, is believed to be a potential adsorbent for heavy metal ions since it not only is shown to lower the concentration of heavy metal ions to below the drainage quality standard, but also it would not cause acidification and hardening of soil which is one of the detrimental effects of synthetic macromolecular adsorbents present.

• Nuclear Engineering and Technology
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• v.4 no.3
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• pp.186-193
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• 1972

For efficient micro scale syntheses of Rose $Bengal-^{131}I$, $Hippuran-^{131}I$, and $H.S.A.-^{131}I$, the dependence of labelling yields on pH, on salt contents, and on the volume of buffer solution in the reaction mixtures as well as the reaction apparatus were studied. pH of 5.6 was optimum for preparation of both Rose $Bengal-_{131}I$ and Hippuran $-^{13}I$ but pH of 8.5 was optimum for preparation of $H.S.A.-^{131}I$. Salt in the reaction mixtures hindered drastically the formation of $Hippuran-^{131}I$ but it slightly increased the labelling yield of H.S.A.. The compactly closed reaction vessels were effective for preparations of both Rose $Bengal-^{131}I$and $Hippuran-^{131}I$ in small volume. Thereupon, the labelling procedures were modified to bring about higher labelling yields and better reproducibilities. By these newly established procedures, the labelling yields of Rose $Bengal-^{131}I$ and $Hippuran-^{131}I$ could be increased even with the home-produced sodium $iodide-^{131}I$ solution containing reducing agent.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.449-455
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• 2009

The principal objective of this study was to determine the quality and potential of DHEA formation after the addition of diosgenin of yam(Dioscorea spp.) during the fermentation of soybean paste. All samples were divided into three groups based on the variety of yam. In sample A, the soy source was not separated from soybean paste and in sample B, the soybean source was separated from soybean paste. The range in salt concentration in the samples was as follows : sample A: 10.5~11.8%, samples B: 7.9~8.8%. However, no substantial differences between the two samples, in terms of salt content, were observed. The crude protein and crude lipid content were found to decrease with the fermentation time of soybean paste(passage of 30 days: 26.4~32.3% and 4.45~5.90%, passage of 60 days: 24.5~28.5% and 3.95~4.90%, respectively). As the fermentation time of soybean paste increased, the nitrogen from amino compounds increased(passage of 30 days: 531.9~687.7 mg%, passage of 60 days: 551.3~706.8 mg%). In regards to color and preference, sample B, where the soy source was separated from soybean paste, was better than sample A, where the two components were not separated. After a soybean paste fermentation time of 60 days, the diosgenin of yam, which was added to the soybean paste, was not detected in tested samples, and the contents of DHEA formation in soybean paste were as follows: sample A: $488.0\pm42.5{\sim}719.3\pm44.8{\mu}g/g$, sample B: $287.3\pm20.6{\sim}482.7{\pm}36.5{\mu}g/g$.