• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.447-452
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• 2003

We had clarified the reactions of the rare earth oxides($RE_2O_3$) with lithium oxide produced in lithium reduction process of oxide fuels. Oxides of scandium, yttrium, praseodymium, neodymium, samarium, europium, gadolinium, ytterbium and lutetium reacted with lithium oxide in the higher concentration than the respective certain critical concentration of lithium oxide and formed complex oxides($LiREO_2$). The critical lithium oxide concentrations for the formation of complex oxides of scandium, yttrium, praseodymium, neodymium, samarium, europium, gadolinium, ytterbium and lutetium oxide were respectively 0.1 wt%, 1.9 wt%, 5.3 wt%, 5.0 wt%, 3.0 wt%, 3.9 wt% 2.9 wt%, 2.6 wt% and 0.3 wt%. Cerium and lanthanum oxide did not react with lithium oxide. These complex oxides obtained from experiments have limited solubility in lithium chloride at $650^{\circ}C$.

• Solar Energy
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• v.18 no.3
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• pp.197-203
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• 1998

A 5 ton/day pilot scale two-phase anaerobic digester was constructed and tasted to treat Korean food wastes in Anyang city. The process was developed based on 3 years of lab-scale experimental results on am optimim treatment method for the recovery of biogas and humus. Problems related to food waste are ever Increasing quantity among municipal solid wastes(MSW) and high moisture and salt contents. Thus our food waste produces large amounts of leachate and bed odor in landfill sites which are being exhausted. The easily degradable presorted food waste was efficiently treated in the two-phase anaerobic digestion process. The waste contained in plastic bags was shredded and then screened for the removal of inert material such as fabrics and plastics, and subsequently put into the two-stage reactors. Heavy and light inerts such as bones, shells, spoons and plastic pieces were again removed by gravity differences. The residual organic component was effectively hydrolyzed and acidified in the first reactor with 5 days space time at pH of about 6.5. The second, methanization reactor part of which is filled with anaerobic fillters, converted the acids into methane with pH between 7.4 to 7.8. The space time for the second reactor was 15 days. The effluent from the second reactor was recycled to the first reactor to provide alkalinities. The process showed stable steady state operation with the maximum organic rate of 7.9 $kgVS/m^3day$ and the volatile solid reduction efficiency of about 70%. The total of 3.6 tons presorted MSW containing 2.9 tons of food organic was treated to produce about $230m^3$ of biogas with 70% of methane and 80kg humus. This process is extended to full scale treating 15 tons of food waste a day in Euiwang city and the produced biogas is utilized for the heating/cooling of adjacent buildings.

• Korean journal of food and cookery science
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• v.25 no.6
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• pp.747-757
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• 2009

The purpose of this study was to enhance the quality of kochujang Apple juice was added to traditional Kochujang at 0%, 20%, 40%, 60 and 80%. Physicochemical and microbial characteristics were periodically investigated during at room temperature during a 90 day fermentation period. The moisture content of the apple Kochujang was higher than that of the control, while the salt content of the apple Kochujang was lower than that of the control, At first, the sweetness of the apple Kochujang showed no significant difference from the control; however, its sweetness increased during the 90 days. In all treatments, the pH value decreased during the fermentation period, while the titratable acidity increased during the fermentation period. Viscosity decreased greatly after 30 days. Sugar reduction was higher in the apple Kochujang than in the control, and its concentration increased with apple juice content. According to the analysis of free sugar, glucose, fructose, and maltose had an especially high ratio in the apple Kochujang. The organic acids detected in Kochujang were citric acid, malic acid, oxalic acid and lactic acids. The content of citric acid and malic acid were higher than the other acids in the apple Kochujang. L, a, and b values generally decreased during the fermentation period. When the Kochujang was made, the number of the total viable cells was $10^7\;CFU/g$. At room temperature, the number steadily increased up to the 30th day, then steadily decreased on the 90th day. After that, there was no significant change. The number of yeasts was $10^6\;CFU/g$ at the end of the 90th day. After the 90th day of fermentation, sensory results showed that the 60~80% apple juice Kochujang showed the best taste, appearance, texture, and overall quality.

• The Korean Journal of Physiology
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• v.11 no.1
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• pp.37-44
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• 1977

In the previous study of the release, excretion, and plasma concentration of aldosterone in normal Koreans, the author found that urinary aldosterone excretion and aldosterone secretion rate of the Korean who usually take high amount of salt are significantly lower, in compared to Americans, although the plasma concentration is only tended to be low. The control of plasma aldosterone level depends on the secretion rate and the metabolic clearance of the hormone. In this experiments, the metabolic clearance rate of aldosterone was determined in normotensive korean and the effects of adrenal stimulations on the rates were also studied in the same subjects. The metabolic clearance rate of the normal Korean was not significantly different from those of the American, and shown a little increase in response to sodium restriction. These results indicate that the decrease in secretion rate rather than the increase in metabolic clearance Tate is the major factor maintaining lower plasma aldosterone level. After furosemide diuresis, on the contrary, the removal of aldosterone showed significant the decrease despite slight increase of secretion rate. This suggest that the reduction in metabolic clearance rate of the hormone during volume depletion found to be major cause of high plasma concentration. Additional potassium supply produced detectable decrease of metabolic clearance rate, but the changes were smaller than that of secretion rate, which suggested that the higher secretion rate could account for elevated plasma concentration of aldosterone rather than metabolic clearance. Above results also support author's previous evidences that the normal Korean who already adapted to a high sodium diet have ability to produce adequate aldosterone activity without producing detectable changes on the metabolic clearance rate under the condition of sodium restriction with approp riate potassium intake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.429-437
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• 1999

A mathematical model was established for estimating changes in pressure and volume of permeable kimchi packages. The model comprises the CO2 gas production from kimchi and permeation of O2, CO2 and N2 through the permeable film or sheet. Using the developed model, the effects of various packaging variables on the pressure and volume changes were analyzed for rigid and flexible packag es of kimchi(3% salt content) at 15oC, and then effect of storage temperature was also looked into. In case of rigid pack of 400g, using the plastic sheet of high CO2 permeability and initial vacuumizing can help to relieve the problem of pressure build up. The lower fill weight can further reduce the pressure, but will result in higher packaging cost. For the flexible package of 3 kg, highly permeable films such as low density polyethylene(LDPE) and polypropylene can reduce the volume expansion. Higher ratio of CO2 permeability to O2 and N2 permeabilities are effective in reducing the volume expansion. Increased surface area cannot contribute to reduction of volume expansion for highly permeable flexible packages of kimchi. For the impermeable packages, pressure and volume at over ripening stage (acidity 1.0%) increase with decreased temperature, while those at optimum ripening stage(acidity 0.6%) change little with temperature. Pressure of permeable rigid LDPE package increases with tem perature at any ripening stage, and temperature affects the volume of flexible LDPE package very slightly. Experimental verification of the present results and package design with economical consid eration are needed as a next step for practical application.

• Journal of Environmental Health Sciences
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• v.36 no.3
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• pp.236-246
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• 2010

In preparative anti-corrosive coating experiments, polyaniline was obtained by reacting an oxidizing agent with the monomer aniline. Further, the primer coating was prepared using a variety of widely-used materials such as urethane resin. For the top coating, epoxy resin and acrylic urethane resin were used. Characteristics of the coatings were assessed according to KS and ASTM specifications, and the structure of the polyaniline was characterized using FT-IR and TGA. For analysis of anti-corrosive properties in salt-spray experiments, measurements of the oxidation state of iron and surface atomic analysis were conducted using XPS and SEM-EDX. Unlike general anti-corrosive coatings which exhibit anti-corrosive effects only as a primer coating, the anti-corrosive coatings using polyaniline as the anti-corrosive pigment showed a marked synergistic effect with the top coatings. In other words, the top coatings not only produce a fine view effect, but also increase, through interaction with the primer coatings, the resistance to diffusion of corrosive factors from the external environment. It was also found that, unlike the heavy metal oxide-forming layer of the passive barrier alone, the polyaniline anti-corrosive pigment oxidized iron at the interface with the iron substrate to form a passive barrier in the oxidic layer, and itself formed a potential barrier layer with anti-corrosive factors from the external environment. Although the passive layer was damaged, the damaged area did not become completely oxidized iron; on the contrary, it showed a tendency to reduction. This can be interpreted such that a passive layer is formed again on the damaged area, and that at the same time there is a tendency to self-healing.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.319-327
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• 2007

Incineration has been regarded as the best developed technology available for organically hazardous waste. However, permitting and siting incinerators to treat hazardous waste such as a waste containing PCBs is very difficult due to the public concerns associated with toxic air emissions. Recently, a lot of alternatives to an incineration have been developed and these technologies have the potential of alleviating public concerns by decreasing emissions of hazardous materials such as dioxins and furans. This paper reviews currently available alternative incineration technologies for various hazardous waste streams. Various categories of non-thermal and thermal alternative incineration technologies have been evaluated in terms of their process operating condition, applicability of a waste stream and their emission of secondary waste. Detailed descriptions of operating principles of several technologies are also provided.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.2
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• pp.75-82
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• 2008

In this study, the photocatalysed degradation of safranin-O was investigated using Au colloids. Au metal nanoparticle wasused to eliminate safranin-O fast in solution. Au nanoparticles were prepared reduction method using $Na_2CO_3$ and PVP in aqueous solution. The degradation of safranin-O was examined using a variety of condition such as concentration of Au colloid or Au salt, reaction pH, and reaction time in the presence of UV light and $H_2O_2$. As the concentration of Au colloid increases, the rate of dye degradation increases. The photo-oxidation of the safranin-O was monitored spectrophotometrically. The properties of Au nanoparticles were characterized by UV-Vis spectroscopy. In addition, catalytic capacities of Au nanoparticles were also determined by UV-Vis spectroscopy.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.550-558
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• 2016

This study was conducted to provide guideline data for future instructional materials and practice guidelines on reforming the dietary life of military personnel in terms of lowering sodium intake. A total of 264 persons were surveyed to obtain basic data on sodium intake and understanding of sodium. The study also examined the practice that is carried forward in this endeavor. The subjects liked 'kimchi' and 'rice with topping', and these could be the reason for higher salt intake. Career soldiers scored higher in terms of nutrition knowledge than enlisted soldiers (p<0.01). Nutrition education concerning sodium intake was statistically insignificant between the two, whereas career soldiers showed a higher experience rate at these nutrition educational events. Career soldiers also had with higher sodium intake than enlisted soldiers, and this difference was statistically significant (p<0.01). In terms of practice, officers were more likely to experience difficulty in putting the theory of less sodium into practice than their enlisted soldiers counterparts (p<0.05), and the main reason behind this difficulty was that they did not feel the need to lower their sodium intake. Soldiers should be well educated about sodium and healthy diet during their service. Education should focus on lowering sodium intake and changing their attitudes and awareness of this issue in order to elicit behavioral changes.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.368-371
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• 2014

A variety of abiotic stresses limit plant growth and crop productivity. Among the abiotic stress, salinity is one of the major harmful stresses to plants. Plant growth-promoting bacterium was isolated from reclaimed land soil of Kyehwa-do and identified as Pseudomonas. Pseudomonas sp. strain G19 produced $7.5{\mu}g/ml$ of indole acetic acid and solubilized 25% of insoluble phosphate after 36 h cultivation. Also, G19 was able to produce a protein that was structurally homologous to 1-aminocyclopropane-1-carboxylate deaminase of Pseudomonas fluorescens KACC10070 playing a role in reduction of ethylene in plant. The strain G19 increased the biomass of Chinese cabbage seedlings grown in the presence of 150 mM NaCl. The results indicated that the strain G19 promoted the growth of Chinese cabbage seedling under salinity stress through microbe-plant interactions.