• Journal of Animal Science and Technology
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• 제61권1호
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• pp.18-27
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• 2019

With South Korea's limited capability of feed production because of its relatively small cultivable area, the country is pushed to depend on foreign feed imports despite the immensely fluctuating price of corn. Hence, intensive efforts to increase the total cultivable area in Korea like extending of farming to mountainous area is being practiced. Corn was planted in Goesan County, a mountainous area in the country. Grain and stover were harvested separately in three harvest periods: early-harvest (Aug 8), mid-harvest (Aug 18), and late-harvest (Aug 28). The nutrient composition such as dry matter (DM), crude protein (CP), crude fat (EE), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), and non-fibrous carbohydrates (NFC) was determined after harvest. Effective degradability (ED) of the major nutrients (DM, NDF, ADF, and CP) were measured through in vitro fermentation of rumen fluid from Hanwoo (Korean cattle). pH, ammonia-N concentration, volatile fatty acid (VFA) concentration, and gas production were periodically measured at 0, 3, 6, 12, 24, 48, and 72 h. Corn grain showed higher nutrient content and ED than stover. It also had higher gas production but its pH, ammonia-N, and total VFA concentration were lower than corn stover. The best nutrient composition of corn grain was observed in early-harvest (high CP, EE, NDF, OM, NFC, and low ADF). Early-harvest of corn grain also had high effective degradability of dry matter (EDDM), effective degradability of neutral detergent fiber (EDNDF), effective degradability of acid detergent fiber (EDADF), and total VFA concentration. On the other hand, the best nutrient composition of stover was observed in mid-harvest (high DM, CP, NDF, and low ADF). EDDM, EDNDF, and EDADF were pronounced in early-harvest and mid-harvest of stover but the latter showed high total VFA concentration. Hence, early and mid-harvested corn stover and grain in a mountainous area preserved their nutrients, which led to the effective degradation of major nutrients and high VFA production.

• 한국물환경학회지
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• 제22권4호
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• pp.678-686
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• 2006

The feasibility of the high-hydrophilic biofilter was examined for application in rural wastewater treatment in Korea. The intermittent trickling biofiter was developed for wastewater treatment of media and examined instantaneous wetting water and immersional wetting water. Melamin foam absorbed 120 times it's weight in water and maintained wetting status than other materials. These characteristics are improvement for application in rural areas showing large variance of amount of influent. The biofilter process was effective in treating organic pollutants; mean removal efficiencies of $BOD_5$ and TSS were above 80%. The average SS concentrations of effluent was showed below $10mg/L^{-1}$ and meet guidelines in special regions, however, the average concentration of $BOD_5$ was about $20mg/L^{-1}$. The removals of T-N and T-P were relatively less effective and removal efficiencies were below 40%. It might meet the guidelines for T-P because of low levels of influent T-P concentration. However, the T-N concentration were too high and further treatment is required. The effluent concentration of $NH_4-N$ showed a significant reduction rate about 43.8%, but part of $NH_4-N$ was transformed to $NO_2-N$ and $NO_3-N$ inside the biofilter through nitrification process. The effluent concentration of org-P was removed about 78.8% of influent concentration by filtration. Considering stable performance and effective removal of pollutant in wastewater, low maintenance, and cost-effectiveness, the hydrophilic biofilter system was thought to be an effective and feasible alternative for decentralized rural areas.

• Biomolecules & Therapeutics
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• 제13권1호
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• pp.41-47
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• 2005

The study was conducted to determine whether oak wood vinegar extract influences blood alcohol concentration and hangover syndrome in healthy volunteers. 2% wood vinegar extract was effective to inhibit increase of blood alcohol concentration after alcohol intake and showed significantly different (P<0.1) compared to placebo. By result of questionnaire of volunteers, wood vinegar extract showed effects improving hangover syndrome. In comparative study about blood alcohol concentration and hangover syndrome of wood vinegar extract and other extract that hangover improvement effect was reported, average maximum blood alcohol concentration was lowered in those taking wood vinegar extract than those taking other extract. At drinking completion 210minutes (T210), blood alcohol concentration of those taking wood vinegar extract was the lowest by 0.063% compared with other extract but was not significantly different between in those taking wood vinegar extract and in those taking other extract. However, wood vinegar extract's experimental group was the highest by 0.462 in decrement rate of blood alcohol concentration and, when did P<0.1 by significance level, indicated difference that mean statistically compared to placebo group uniquely. At those taking wood vinegar extract, the improvement rate and the aggravation rate of hangover syndrome was each 87%, 2%. Thus it was concluded that wood vinegar extract showed excellent alcohol oxidation and was effective in hangover improvement.

• 한국의류학회지
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• 제28권7호
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• pp.873-881
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• 2004

This research was aimed to investigate the effect of enzyme and the addition of chelators on rotting of the Kenaf bast. Enzyme rotting was effective only when the chelators were added with the enzyme. EDTA was a more effective chelator than oxalic acid under 1% concentration. There was no difference in the rotting effect under different enzyme concentration levels, and under different treatment time and temperature. Therefore, it was found that enzyme rotting can be carried out with low enzyme concentration(0.125%) at room temperature. Retting time can be shortened when higher enzyme concentration and higher temperature are applied. Cellulose I structure of kenaf fiber did not change after enzyme rotting, and different enzyme concentration did not affect the crytallinity structure. Non-cellulosic matters such as hemicellulose, lignin, and pectin were present in the descending order in the enzyme rotted kenaf fiber, and there were no differences in their amounts due to enzyme concentration levels. There was no difference in the dyeabilities of kenaf fiber rotted with different enzyme concentration levels. Enzyme rotted kenaf fiber showed better cyeability when pectin, lignin, and hemicellulose were removed.

• 상하수도학회지
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• 제19권1호
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• pp.68-77
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• 2005

This study was performed to evaluate the application of corrosion inhibitor and to examine the correlation between corrosion rate and red water in a series of batch tests and a test using auto corrosion monitoring system at A water treatment plant in Gyeonggido. The corrosion study in the auto corrosion monitoring system indicated that Fe concentration decreased by 30~50% and corrosion rate also reduced remarkably with corrosion inhibitor at $1.8mg\;PO_4/L$. After addition of corrosion inhibitor, it was indicated the effective adsorption of the inhibitor on the surface of the pipe line forming a protective film. The corrosion rate increases with the increase in Fe concentration. With $1.8mg\;PO_4/L$ of corrosion inhibitor, the corrosion rate decreased remarkably. Fe concentration had correlation to not only red water problems but also the corrosion rate that actually dissolved into the water, primarily due to the deposition of oxidized iron or other compounds as a scale, which serves as a large reservoir of corrosion by-product. Therefore, corrosion rate can be estimated by Fe concentration. For these reasons, an effective corrosion inhibitor is also an effective red water control reagent. The effect of the corrosion inhibition can last for some time even the application the corrosion inhibitor is discontinued. For the cost effective and efficient corrosion control, the concentration and timing of corrosion inhibitor addition must be determined properly.

• 대한기계학회논문집
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• 제19권7호
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• pp.1731-1740
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• 1995

Experimental investigations have been made to study the double-diffusive nature of convection of an initially stratified salt-water solution due to heating from below in a rotating cylindrical cavity. The objective is to examine the flow phenomena and the heat transfer characteristics according to the changes in temperature gradient, concentration gradient and rotating velocity of cavity. Thermal and solutal boundary conditions at side wall are adiabatic and impermeable, respectively. The top and bottom plate are maintained each at constant temperature and concentration. The cavity is put into a state of solid body rotation. Like the stationary case, the types of initially-formed flow pattern are classified into three regimes depending on the effective Rayleigh number and Taylor number; stagnant flow regime, single mixed-layer flow regime and successively formed multi-mixed layer flow regime. At the same effective Rayleigh number, the number of initially-formed mixed layer and its growth rate decrease as the effect of rotation increases. The temperature and concentration profiles are both uniform in each layer due to convective mixing in the layered-flow regime, but look both liner in stagnant flow regime and single mixed-layer flow regime. At the interface between adjacent layers, the temperature changes smoothly but the concentration changes rapidly.

• 한국식품영양학회지
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• 제14권3호
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• pp.222-227
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• 2001

The production results of the oriental functional beverage, which is aimed at reducing the alcohol concentration in blood, are as follows. Different kinds of herb medicine ingredients were combined to achieve the balance between Yin And Yang. They were grouped according to their respective characteristics and extracted by heat, Then they were combined and produced following the most effective mixture ratio. The drink produced by this way consisted mainly of water, Sugar, mineral, protein and fiber were partially contained. Among the minerals, the proportion of calcium, potassium, magnesium was high and iron was also contained. This drink turned out to be effective in reducing the alcohol concentration in blood within a very short time when it was taken once after drinking and taken aging 30 minutes later, which would double the dosage. This result shows that development of such a functional beverage using the herbal medicine, At the same time it will play an important part in reducing the alcohol concentrate in blood after drinking liquors.

• 상하수도학회지
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• 제26권1호
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• pp.97-106
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• 2012

To investigate the application of corrosion inhibitor on water supply pipes, turbidity, magnitude of corrosion, composition of scale and concentration of metals from an old steel pipe were analysed under inhibitor addition. The concentration of turbidity, iron and copper from the pipes under inhibitor application was 12 ~ 14% of the case which no inhibitor was applied, which suggests the application of inhibitor was very effective for internal corrosion control. In addition, SEM, EDX, XRD and XRF test results showed that application of inhibitor was effective for the decrease of iron concentration and increase of oxygen, phosphorus and calcium concentration, which suggested the existence of protective layer. Therefore, the occurrence of red water will be significantly decreased when inhibitor was applied to the old steel pipes.

• 한국수산과학회지
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• 제36권5호
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• pp.509-514
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• 2003

We performed the experiment to determine the effective factors, such as the initial concentration of protein, pore size of air distributor, SAV (superficial air velocity), pH, salts and temperature related to foaming characteristics. The foam height in a foam generator was increased with the increase of the initial protein concentration and the decrease of pore size. As SAV was increased, the foam height was increased, and the optimum SAV was 0.84 cm/sec. The foam height was highest in the acid region and it was increased with the increase of salt concentration of NaCl and $NaHCO_3.$ The removal efficiencies of TSS (total suspended solid) and turbidity decreased with the increase of the initial protein concentration in the batch foam separator.

• 한국염색가공학회지
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• 제10권3호
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• pp.50-56
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• 1998

Nonwoven fabric was treated with chitosan solution to impart antimicrobial activities by pad-dry method. Antimicrobial activity was measured by Shake Flask Method. Two chitosans of different molecular weight(Mw) with similar degree of deacetylation(DDA) were used : ca. 1,800(chitosan oligomer : DDA 84%) and 180,000(DDA 86%). Chitosan oligomer displayed high antimicrobial activity against P. vulgaris at 0.01%, S. aureus and E. coli at 0.05% treatment concentration, shelving above 90% of reduction rate. Chitosan of Mw 180,000 was effective against S. aureus, E. coil and P. vulgaris at 0.05% treatment concentration, showing almost 100% reduction rate. While chitosan of Mw 180,000 shelved reduction rate above 75% against K. pneumoniae and P. aeruginosa at 0.5% treatment concentration, chitosan oligomer was not effective against them. Fabrics become stiffer and less air permeable as treatment concentration increases. Liquid strike-through time of the sample treated with 0.5% chitosan oligomer solution (3.0 sec) was comparable with a hydrophilic finished sample commercially available(2.6 sec).