• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.156-163
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• 2007

This study was conducted to evaluate the liquefying efficiency of mixed organic fertilizer in different conditions. The organic fertilizer was composed of sesame oil cake, rice bran, fish meal, ground bone meal etc, and made by fermenting process. It included $23g\;kg^{-1}$, $17.0g\;kg^{-1}$, $23.9g\;kg^{-1}$, $290g\;kg^{-1}$ of N, $P_2O_5$, $K_2O$, organic matter, respectively. In one test, the mixed organic fertilizer was added in the proportion of 10% to water 90% and aerated continuously, for 2, 8 hours per day, and not aerated as control. In the other test, ratios of organic fertilizer to water were 5%, 10%, 20% and aerated for 2 hours a day. With the increase of liquefying time, pH, EC and $NH_4-N$ increased without relation to aeration time. After 10 days, liquid organic fertilizer aerated for 2 hours a day contained $634mg\;N\;kg^{-1}$, $68.1mg\;P_2O_5\;kg^{-1}$, $453mg\;K_2O\;kg^{-1}$, which was not significantly different from 8 hours a day or continuous aeration. Then extraction ratios of inorganic contents were 27.6%, 4.0% and 18.9%, respectively. Continuous aeration resulted in increasing the viable number of aerobic bacteria, spore forming bacteria and fungi in liquefied solution. Higher ratio of organic fertilizer to water increased EC, $NH_4-N$ and other inorganic matter contents, but decreased extraction ratio of nutrients in liquid fertilizer. The liquid organic fertilizer of 20% contained $1,140mg\;N\;kg^{-1}$, $35.4mg\;P_2O_5\;kg^{-1}$, $544mg\;K_2O\;kg^{-1}$ after 10 days. Then extraction ratios were 24.8%, 2.4% and 13.6%, respectively. The ratio of organic fertilizer to water was positively correlated with only spore forming bacteria, Pseudomonas spp. among microorganisms.

• Journal of the Korean earth science society
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• v.41 no.6
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• pp.630-646
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• 2020

In rural areas, nitrate-nitrogen (NO3-N) pollution caused by agricultural activities is a major obstacle to the use of shallow groundwater as domestic water or drinking water. In this study, the water quality characteristics of shallow groundwater in Hyogyo-ri agricultural area of Yesan-gun, Chungcheongnam-do province was studied in connection with land use and chemical composition of soil layer. The average NO3-N concentration in groundwater exceeds the domestic and agricultural standard water qualities of Korea and is caused by anthropogenic sources such as fertilizer, livestock wastewater, and domestic sewage. The groundwater type mainly belongs to Ca(Na)-Cl type, unlike Ca-HCO3 type, a general type of shallow groundwater. The average NO3-N concentration (7.7 mg L-1) in groundwater in rice paddy/other (upstream, ranch, and residential) area is lower than the average concentration (22.8 mg L-1) in farm field area, due to a lower permeability in paddy area than that in farm field area. According to the trend analysis by the Mann-Kendall and Sen tests, the NO3-N concentration in the shallow groundwater shows a very weak decreasing trend with ~0.011 mg L-1yr-1 with indicating almost equilibrium state. Meanwhile, SO42- and HCO3- concentrations display annual decreasing trend by 15.48 and 13.15%, respectively. At a zone of 0 to 5 m below the surface, the average hydraulic conductivity is 1.86×10-5 cm s-1, with a greater value (1.03×10-4cm s-1) in sand layer and a smaller value (2.50×10-8 cm s-1) in silt layer.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.27-41
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• 1968

In order to clarify the effect of various forms or phosphate on the production of paddy in Korea and to find out the superiority of any form, a number of field and pot experiments involving various phosphate fertilizers were carried out in addition to conducting one each of sand culture and soil culture pot experiments in 1963 and 1964. The results of these studies are summarized as follows: 1. In sand culture experiment, the best effect of a phosphate fertilizer was obtained with the mono-calcium phosphate which is soluble in water, followed by citric acid soluble phosphate such as fused phosphate and di-calicum phosphate. However, in the pot culture and field experiments, fused phosphate had shown it's superiority than triple superphosphate which contains water soluble form of phosphate followed by hypo phosphate, roasted phosphate, compound fertilizer, and slag phosphate. The effect of rock phosphate was the least in most cases. 2. The superiority of fused phosphate to triple super phosphate in soil culture was supposed to be: a) The fused phosphate can neutralize the soil acidity. b) The fused phosphate can supply magnesium and magnesium lead to the balanced conditions of exchangeable bases in soils. c) The magnesium in the fused phosphate helps the transportation of phosphate, and regulate the absorption of the element.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.537-543
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• 1993

The effect of agitation on liquid-liquid dispersion was investigated in an immisible liquid phase(n-hexane/water) system. Four different types of six-bladed turbine impellers were used: a flat blade, two screen blades and a solid edged 60 mesh screen blade. We found that the extent of dispersion of organic phase and power consumption of agitator were decreased in the order of flat, solid edged, 60 mesh, and 40 mesh blades at same agitation speed. And the minimum agitation speed for complete dispersion of organic phase was increased with increasing volume fraction of organic phase. Also, mean diameter of liquid droplets of dispersed phase was decreased with increasing agitation speed and it was increased in the order of solid edged, flat, 60 mesh, and 40 mesh screen blades at same agitation speed. At complete dispersion, the minimum power consumption was not vary significantly with impeller blade types, but the solid edged screen blade impeller gave the smallest and uniform sizes of liquid droplets, and it had a good performance for liquid-liquid dispersion. In this condition, Power number was not affected by Reynolds number and it was constant in turbulent flow region, and Sauter mean diameter($d_{32}$) of liquid droplets was expressed as a function of volume fraction of organic phase(${\phi}$) and Weber number($N_{We}$) as follows: $d_{32}/D=a(1+b{\phi})N_{We}{^{-0.6}}$.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1827-1833
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• 2014

This study has been carried out to present the valuation system of soil carbon sequestration potentials of soil in accordance with the new climate change scenarios(RCP). For that, by analyzing variation of soil carbon of the each type of agricultural land use, it aims to develop technology to increase the amount of carbon emissions and sequestration. Among the factors which affects the estimation of determining the soil carbon model and influence power after the measurement on soil organic carbon, under the center of a causal relationship between the explanatory variables this study were investigated. Chemical fertilizers (NPK) decreased with increasing the amount of soil organic carbon and as with the first experimental results, when cultivating rice than pepper, the fact that soil organic carbon content increased has been found out. The higher the carbon dioxide concentration, the higher the amount of organic carbon in the soil and this result is reliable under a 10% significance level. On the other hand, soil organic carbon, humus carbon and hot water extractable carbon has been found out that was not affected the soils depth, sames as the result of the first year. The higher concentration of carbon dioxide, the higher carbon content of humus and hot water extractable carbon content. According to IPCC 2006 Guidelines and the new climate change scenario RCP 4.5 and the measurement results of the total amount of soil organic carbon to the crops due to abnormal climate weather, 1% increase in atmospheric carbon dioxide concentration was found to be small when compared to the growing rate of increasing 0.01058% of organic carbon in the soil.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.593-597
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• 2004

This study was conducted to investigate the quality characteristics of liquid calcium acetate (LCAs) and solid calcium acetate (SCAs), Br-LCA, Pe-LCA and Ap-LCA as liquid form, Br-SCA, Pe-SCA and Ap-SCA as solid form. Calcium acetate was prepared by reacting of vinegars [brown rice (Br), persimmons (Pe) and apple (Ap)] and ash of black snail in order to obtain natural water soluble calcium resources. The pHs of the vinegars for preparing calcium acetate (CA) were the range of 2.34 ∼ 3.06, and the contents of the ash of black snail which reacted to 100 mL of the vinegars were 20.43∼23.50 g. The yields of solid CAs from 100 mL of the vinegars were 11.02∼13.01 g. The colors of liquid and solid CAs were light yellow in Ap-LCA and Ap-SCA, brown in Br-LCA and Br-SCA, dark brown in Pe-LCA and Pe-SCA. Calcium contents of Br-LCA, Pe-LCA and Ap-LCA were 3.02, 2.06 and 2.30% (w/v), and those of Br-SCA, Pe-SCA and Ap-SCA were 27.15, 16.31 and 19.48% (w/w), respectively. The solubilities of the solid CAs were 36.82 ∼ 39.92% (w/v) in distilled water, 32.05 ∼ 39.04% (w/v) in Soju, 13.12 ∼ 18.65% (w/v) in thick soysauce, 38.35 ∼ 38.90% (w/v) in ionic beverage, 33.47 ∼ 35.58% (w/v) in yoghurt, while the solid CAs formed the curds in soymilk and milk. The sour and bitter taste of the CAs were lower, while the astringent taste, fishy flavor and savory taste were higher than those of standard CA.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.12
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• pp.1701-1711
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• 2012

Okinawan Awamori is produced by fermenting steamed indica rice with black mold, yeast, and water. Awamori-pressed lees is a by-product of the Awamori production process. Tofu lees is a by-product of the Tofu production process. This research consisted of two experiments conducted to elucidate whether or not dried Awamori-pressed lees and Tofu lees can be used as a mixed feed ingredient for raising female goats. In experiment 1, digestion trials were conducted to ascertain the nutritive values of dried Awamori-pressed lees and dried Tofu lees for goats. The digestible crude protein (DCP) and total digestible nutrients (TDN) contents of dried Awamori-pressed lees and Tofu lees were 22.5%, 22.5% (DCP), and 87.2%, 94.4% (TDN) respectively. In experiment 2, 18 female goats (Japanese Saanen${\times}$Nubian, three months old, body weight $15.4{\pm}0.53$ kg) were divided into three groups of six animals (control feed group (CFG), Awamori-pressed lees mixed feed group (AMFG), Tofu lees mixed feed group (TMFG)). The CFG control used feed containing 20% soybean meal as the main protein source, while the AMFG and TMFG treatments used feed mixed with 20% dried Awamori-pressed lees or dried Tofu lees. The groups were fed mixed feed (volume to provide 100 g/d increase in body weight) twice a day (10:00, 16:00). The klein grass hay and water was given ad libitum. The hay intake was measured at 08:00 and 16:00. Body weight and size measurements were taken once a month. At the end of the experiment, a blood sample was drawn from the jugular vein of each animal. The DCP and TDN intakes in AMFG and TMFG showed no significant difference to the CFG. Cumulative measurements of growth in body weight, withers height, chest depth, chest girth, and hip width over the 10 mo period in the AMFG and TMFG were similar to the CFG. By contrast, cumulative growth in body length and hip height in the AMFG and TMFG tended to be larger than the CFG. Cumulative growth in chest width in the AMFG was significantly larger (p<0.05) than the CFG. Blood parameter values were similar to those in normal goats reported by other scientists. The coats of the AMFG and TMFG animals looked shinier than the animals in the CFG. The results demonstrate that dried Awamori-pressed lees and Tofu lees can be used as a feed ingredient for the raising female goats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1365-1370
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• 2007

The inhibitory effects of the water and methanol extracts of Jakwangdo and Honghyangmi on the rat microsome lipid peroxidation and growth of four human cancer cells such as HepG2 (liver cancer), SNU-1 (stomach cancer) MCF-7 (breast cancer) and SNU-C4 (colon cancer) were examined. The methanol extracts of red colored rices showed the antioxidant activity and growth inhibitory effects of cancer cells. However, water extracts did not show the activities. Inhibitory activities of methanol extracts of Jakwangdo and Honghyangmi against lipid peroxidation of rat microsome was 80% and 68%, respectively, at the concentration of 1 mg/assay. Jakwangdo methanol extracts showed the highest growth inhibitory activity in MCF-7 cells among the cancer cells tested. The methanol extracts of red colored rices were further fractionated with hexane, chloroform, ethyl acetate and butanol. Both chloroform and hexane fractions showed strong growth inhibitory activity in HepG2 and MCF-7 cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.441-449
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• 2013

This study was conducted to ferment high quality vinegar by using Omija fruit. Strains of bacteria producing acetic acid were isolated from spoiled Omija wine (OV1 and OV2) and traditional rice vinegar (RA). The bacterium was from optimally-oxidized Omija wine containing 6.0% ethanol and from Omija vinegar with 5.21% acetic acid by 14 days of fermentation. The Omija vinegar got the highest sensory score (5.80) among several commercial vinegars. The Omija vinegar showed a potent antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas fluorescens by the paper disc test, while Omija wine had limited antibacterial activity against S. aureus and P. fluorescens. The diameter of the clear zone formed by the paper disc test using Omija vinegar was not less than 9.5 mm. The DPPH free radical-scavenging activity of Omija wine was higher than that from Omija water extracts. The nitrite scavenging ability of Omija wine (36.98% of all nitrites present) and vinegar (31.14%) was higher than that from Omija water extracts (22.53%). Omija vinegar exhibited strong antibacterial and antioxidant activities. In conclusion, we prepared high quality vinegar from dried Omija.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.282-289
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• 2014

BACKGROUND: Methane($CH_4$) is considered as the secondmost potent greenhouse gas after carbon dioxide ($CO_2$). Methanogenesis is an enzyme-mediated multi-step process by methanogens. In the penultimate step, methylated Co-M is reduced by methyl Co-M reductase (MCR) to $CH_4$ involving a nickel-containing cofactor F430. The activity of MCR enzyme is dependent on the F430 and therefore, the bioavailability of Ni to methanogens is expected to influence MCR activity and $CH_4$ production in soil. In this study, different doses of EDTA(Ethylene Diamine Tetraacetic Acid) were applied in flooded soils to evaluate their suppression effect on methane production by chelating Ni of methanogenesis cofactor. METHODS AND RESULTS: EDTA was selected as chelating agents and added into wetland and rice paddy soil at the rates of 0, 25, 50, 75, and $100mmol\;kg^{-1}$ before 4-weeks incubation test. During the incubation, cumulative $CH_4$ production patterns were characterized. At the end of the experiment, soil samples were removed from their jars to analyze total soil Ni and water-soluble Ni content and methanogen abundance. Methane production from 100 mmol application decreased by 55 and 78% in both soils compared to that from 0 mmol. With increasing application rate of EDTA in both soils, water-soluble Ni concentration significantly increased, but total soil Ni and methanogen activities showed negative relationship during incubation test. CONCLUSION: The decrease in methane production with EDTA application was caused by chelating Ni of coenzyme F430 and inhibiting methanogenesis by methyl coenzyme M reductase. Consequently, EDTA application decreased uptake of Ni into methanogen, subsequently inhibited methanogen activities and reduced methane production in flooded soils.