• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.79-88
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• 2012

Small amount of salt and various microorganisms are contained in natural soils or clays near the shore. In this study, most common clay minerals such as kaolinite and bentonite are used to evaluate the effect of salt and microorganism on liquid and plastic limits. The effect of time after mixing clays with water was also investigated for the consistency limits of clays. The test was conducted immediately, 1 day, or 7 days after mixing soils. For liquid limit tests two different test methods were used, the percussion cup method by Casagrande and the fall cone method. When sea water or microbial solution was used for mixing soils rather than distilled water, the liquid limit of kaolinite decreased by 6-15% and that of bentonite further decreased up to 37-53%. The liquid limit obtained from the fall cone method was approximately 10% for bentonite and 20% for kaolinite, which are higher than those from the percussion cup method. The effect of time on liquid and plastic limits was significant for those tested immediately or 1 day later but the values obtained after 1 day or 7 days did not vary a lot, regardless of soils, mixing waters or test methods.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.337-337
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• 2004

As one of researches for the P ＆ T purposes, a basic experiment on the recovery of actinide elements from the mixture with rare earth elements by means of electrorefining using a liquid cadmium cathode in the LiCl-KC1 eutectic melt was carried out. In order to examine the behaviors of electrodeposition of metal ions on a liquid electrode, recovery experiments of rare earth metals resulting from forming electrodeposits were performed by a galvanostatic electrolysis method at various current densities. A cyclic voltammetric technique was applied to determine reduction-oxidation potential of each metal element in the melt and to detect the changes of the multi component melt composition for on-line monitoring. Also, a collaboration study with RIAR was completed to test the preliminary feasibility on a recovery of actinide elements from the mixture with rare earth elements using a liquid cadmium cathode and actinide metals. Experimental results showed that the ratio of actinides to rare earths, 9: 0.5∼1 led to the rare earth content of about 5∼10 wt% in the deposit.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.462-471
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• 2017

A more efficient use of nutrients from organic sources can benefit both farmers and water quality in agriculture. In this paper we reviewed information related to the regulations and guidelines of a swine liquid fertilizer to propose an establishment scheme for the official standards of swine manure slurry as a liquid fertilizer for organic farming. According to the law of establishment and designation of official standard of fertilizers, the liquid fertilizer made with pig liquid manure belongs to the byproduct fertilizer as of one of organic fertilizer. However, the official standards for byproduct fertilizers including the liquid fertilizer set by the Rural Development Administration (RDA), especially for a liquid swine manure fertilizer, should be revised to meet the goals of laws pursuing the environmentally sound agriculture, especially for organic farming because the terms and relevant standards need additional specific standards alike the standards such as impurities and parameter for declaration in EU. Therefore, it is suggested that official standards for byproduct fertilizers should be revised with respect to nutrient, salt content as of SAR and Na content instead of NaCl. Also we need to develop the maximum limit of heavy metals in soil to which the liquid fertilizer can be applied, as well as application rate depending on EC of the liquid fertilizer.

• Fire Science and Engineering
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• v.19 no.3 s.59
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• pp.13-19
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• 2005

An experimental study is presented for extinguishing characteristics of liquid fuel fire by water mist containing sodium acetate trihydrate. To evaluate the extinguishing performance of water mist containing an additive, the evaporation characteristics of a water droplet on a heated surface was examined. The evaporation process was recorded by a charge-coupled-device camera. Also, small-scale extinguishing tests were conducted for n-heptane pool fire in ventilated space to measure flame temperature variation. The average evaporation rate of a water droplet containing an additive was lower than that of a pure water droplet at a given surface temperature due to the precipitation of salt in the liquid-film and change of surface tension. In case of using an additive, the flame temperature was lower than that of pure water at a given discharge pressure and it was because the momentum of a water droplet containing an additive was increased reducing flame size. And also dissociated metal atoms, sodium, were reacted as a scavenger of the major radical species OH^-,\;H^+$ which were generated for combustion process. Moreover, at a high pressure of 4MPa, the fire was extinguished through blowing effect as well as primary extinguishing mechanisms.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.347-351
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• 2013

The preparation of glycerol carbonate (GC) from urea through carbonylation with renewable glycerol was investigated by using ionic liquid catalysts. It was found that quaternary ammonium salt and imidazolium salt ionic liquids with a shorter alkyl chain length and higher nucleophilic anion showed better catalytic performance. The effects of reaction temperature, reaction time and degree of vacuum on the reactivity of TBAC catalyst ware discussed. Zinc chloride ($ZnCl_2$) was used as co-catalyst with the ionic liquid catalyst. The mixed catalyst showed a synergy effect on the glycerol conversion and GC yield probably due to the acid-base properties of the catalysts.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.116-122
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• 1977

The volatile flavor components of Kimchis were identified and the volatiles of fermented Kimchis (1.29% NaCl and 4.89 NaCl) were compared with those of raw Kimchi (1.29% NaCl). After the existence of carbonyls and sulfur compounds were confirmed by precipitation method, vacuum distillation was carried out to collect the volatiles of Kimchis in traps submerged in ice+salt, dryice-acetone and liquid N, respectively. The volatile flavor components were identified by GLC. The results were; 1. 17 volatile flavor components of Kimchis were identified by comparison of retention time with those of known compounds and acetaldehyde, acetone, ethanol, ethyl sulfide were positively identified by m.p., IR, UV, TLC. etc. 2. Ethanol was the most abundant volatiles of Kimchis and the content was much higher in fermented low salt Kimchi than in unfermented low salt Kimchi. 3. On the contrary, acetaldehyde and volatile sulfur compounds were reduced in fermented Kimchis, especially in fermented low salt Kimchi.

• Korean journal of food and cookery science
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• v.11 no.3
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• pp.226-232
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• 1995

This study is a result of the experiments to determine the optimum conditions of salting of Chinese cabbages for making tasty Kimchi. For the experiments, various methods of salting of Baechu were set up and the best method of salting had prepared Kimchi to investigated the best salt kind. In the two best results by method of salting salt kind, were investigated for salting time of Kimchi. There were certain amounts of Kimchi had prepared for each case of the combinations of the three conditions. Every case of Kimchi was refrigerated and was evaluated by sensory tests. In the salt concentration, pH and acidity of the Kimchi were measured. The results are as follows; In three cases of Kimchi, for salt concentration, level of 2.4-3.0$^{\circ}$ was maintained in Kimchi solid from the beginning to the end, while it was high in the beginning and gradually lowered in Kimchi liquid. The level of pH in both solid and liquid of Kimchi quickly dropped at the beginning of fermentation period and turned slow as time passed. And the level of acidity was increased little bit in the beginning, but it suddenly multipied until the third day of preservation. Since then, it had increased gradually thereafter as it was before. This experiments show that Kimchi can be the best taste in the case of Chinese cabbage soak in brine- free natural salt are kept for five hours.

• Food Science and Preservation
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• v.22 no.6
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• pp.859-866
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• 2015

The purpose of this study was to develop a supplemental healthy food that can help prevent high blood pressure-related diseases caused due to the excessive consumption of sodium in salt. This was achieved by using ion-displacement techniques to produce mineral salt with lower sodium content by using fermented brown rice by-products rich in minerals. Mineral salt containing 2019.2 mg/100 g of potassium, 678.5 mg/100 g of magnesium, 48.7 mg/100 g of calcium, and 19.5 mg/100 g of sodium was obtained by fermenting brown rice by-products to create a culture medium for the mineral salt. Mineral salt containing 1769.7 mg/100 g of potassium, 573.6 mg/100 g of magnesium, 35.3 mg/100 g of calcium, and 19.5 mg/100 g of sodium was obtained by filtering and refining the by-product extract of fermented brown rice. The results showed that when the stream velocity of the instrument used for electrolysis was 200 mL/min and the current and the concentration of the reactive liquid in the purified water chamber were higher, the effect of electrolysis was greater. Ion hot water extraction of the fermented brown rice by-products improved by up to 95% and was collected as purified water within 90 min of the reaction time. Chloride ions with pH 7.4 were produced by mixing sodium hydroxide in a purified saline water chamber with electro-analyzed water. The salt produced in this study contained low sodium, 5.7~30%, as compared to 40% sodium content of the normal salt.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.5
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• pp.575-581
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• 2015

Although disinfection in drinking water treatment plants provides a safer water supply by inactivating pathogenic microorganisms, harmful disinfection by-products may be formed. In this study, the disinfectant, chlorine, was produced on-site from the electrolysis of salt (NaCl), and the by-products of the disinfection process, bromate and chlorate, were analyzed. The provisional guideline levels for bromate and chlorate in drinking water are $10{\mu}g/L$ and $700{\mu}g/L$, in Korea, respectively. Bromide salt was detected at concentrations ranging from 6.0 ~ 622 mg/kg. Bromate and chlorate were detected at concentrations ranging from non-detect (ND) ~ 45.3mg/L and 40.5 ~ 1,202 mg/L, respectively. When comparing the bromide concentration in the salt to the bromate concentration in the chlorine produced by salt electrolysis, the correlation of bromide to bromate concentration was 0.870 (active chlorine concentration from on-site production: 0.6-0.8%, n=40). The correlation of bromate concentration in the chlorine produced to that in the treated water was 0.866.

• Journal of Electrochemical Science and Technology
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• v.2 no.2
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• pp.63-67
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• 2011

To examine the effects of a two-cation ionic liquid as an electrolyte component of a supercapacitor, 1,4-bis(3-methylimidazolium-1-yl)butane tetrafluoroborate ($MIBBF_4$), dissolved in propylene carbonate (PC) or acetonitrile (ACN), is newly synthesized and tested here for potential use as an electrolyte of capacitor. The $MIBBF_4$ salt exhibits higher ionic conductivity in ACN than in PC. The supercapacitive properties of capacitors containing an activated carbon electrode and various electrolytes are evaluated using cyclic voltammetry and electrochemical impedance spectroscopy. The capacitor adopting the $MIBBF_4$/ACN electrolyte shows the largest specific capacitance at low scan rates, whereas the capacitor adopting the 1-ethyl-3-methylimidazolium tetrafluoroborate $(EMIBF_4)$/ACN electrolyte shows the largest specific capacitance at high scan rates.