• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.155-163
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• 1999

Nutrient balance during rice cultivation in the paddy of a local area under the environmental protection for drinking water supply was investigated. To compare nutrient balance in the paddy soil applied with different types of fertilization, 7 treatments were selected as followings : Recommended level of chemical fertilizers(R), Conventional fertilization(CF), Fresh cow manure(FCM), Cow manure compost(CMC), Straw compost+reduced chemical fertilizer(SCF), Fresh straw+recommended level of fertilizers(FSC), and no fertilization as control(C). Here, FCM, CMC and SCF were applied at the same level of total nitrogen as recommended in R. Rice yield was the highest in the recommendation(R) and fresh cow manure (FCM) treatments with $6,730kg\;ha^{-1}$(index 100), and followed by SCF (index 98), FSC (index 98), CMC(index 94), and CF(index 94). But statistically significant difference was not recognized among treatments except the control. Nitrogen infiltration loss was high in the simple chemical fertilizer treatments with $63kg\;ha^{-1}$ in CF and $58kg\;ha^{-1}$ in R during rice cultivation, respectively. Nitrogen infiltration loss was decreased below half level of chemical fertilizer treatments with cow manure treatments ($23kg\;ha^{-1}$ in FCM and $27kg\;ha^{-1}$ in CMC) and with reducing chemical fertilizer treatment by adding straw compost ($25kg\;ha^{-1}$). Phosphate was not leached during rice cultivation in paddy soil of a fluvial deposit type, in which oxidation horizon was developed broadly under around 15 cm depth of surface soil. Phosphate balance (A-B) was closed to 0 in all treatments except cow manure treatment (CMC), in which it was $+30kg\;ha^{-1}$ and show the possibility of over accumulation of phosphate by continuously replicated application of cow manure compost. Potassium balance was negative value in all but straw recycling treatment (FSC). It means that potassium was continuously supplied from soil minerals, uptaken by plants or eluted out of soil. In conclusion, by substituting inorganic fertilizer for organic fertilizer or reducing application rate of chemical fertilizer through mixing organic fertilizer, it would be possible to achieve the same rice yield as in the recommendation treatment and to decrease nutrient leaching below half level in rice paddy soil.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.414-419
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• 2005

This study was performed to compare the treatment efficiencies of two media, newly developed Bio-rock and conventional gravel, in soil clothing contact oxidation process. The composition of synthetic wastewater were $COD_{Cr}$ $150{\sim}370\;mg/L$, $BOD_5$ $150{\sim}270\;mg/L$, T-N $20{\sim}60\;mg/L$, T-P $5{\sim}25\;mg/L$, pH 7 and 2 mL/L of trace element solution. The experiment using two reactors was comparatively conducted for the flow rate of 40 L/d for 13 months, respectively. Initially Bio-rock reactor was increased to pH 12 due to $Ca(OH)_2$ with hydration of cement, but gravel reactor was dropped to pH 4 due to the degradation of organic material and nitrification. This significant pH variation deteriorated the growth and activity of microorganism. But the high pH of Bio-rock seems favorite to ammonia stripping and precipitation of phosphate. Such pH variation of Bio-rock and gravel reactors were finally stabilized to pH 8 and pH 6, respectively. The removal efficiencies of organic compounds from Bio-rock reactor were 96% of $COD_{Cr}$, 98% of $BOD_5$, 80% of T-N and 85% of T-P which stably coping against variation of influent concentration. But those of gravel reactor were 96% of $COD_{Cr}$, 96% of $BOD_5$, 42% of T-N and 40% of T-P, respectively. The Bio-rock was 2 times higher than T-N and T-P in treatment efficiency. And electron-microscopic examination showed that Bio-rock was more favorable to microbial adherence than gravel. The microbial populations were $5.2{\times}10^6\;CFU/mL$ of Bio-rock reactor compared to $2.6{\times}10^6\;CFU/mL$ in gravel reactor. In result Bio-rock was favor to microbial adherence and high treatment efficiency in spite of variation of influent concentration which had the advantages in saving running time and reducing site requirement.

• Journal of Conservation Science
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• v.23
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• pp.11-24
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• 2008

A physical characteristics and chemical compositions change by weathering on the granite were examined for the conservation treatment of the Mireuksaji temple stone pagoda. The natural weathered granite was collected from the Mt. Mireuk, and divided into the classification standards based on weathering degrees and strength measured by rock-test hammer. The results from comparison of the strength measured by undestructive rock-test hammer and the strength values converted from ultrasonic velocity showed that each strength measurement value was proportionate. The water absorption of the sample was 1.68 to 0.20%. The F-type of fresh rock was not naturally saturated and the WW-type was naturally saturated but took quite a long time. The water absorption was increased gradually in order of SW-type, the MW-type and the HW-type according to weathering condition. The CW-type samples showed the highest water absorption among the weathered classification samples. Through dyeing test, it was found out that only the feldspar was dyed out of the F-type and the WW-type. The SW-type and the MW-type were distinguished by the fact that plagioclase being dyed. And dyed area was expanded to quartz crack in HW-type and CW-type. Physical change by weathering of the rock-forming minerals could be classified with 3 grades. Through the XRD analysis, albite among the rock-forming mineral showed remarkable decrease. SEM-EDX analysis of the component change in the rock-forming minerals such as biotite, plagioclase, and orthoclase, showed that in case of highly-weathered grade samples compared with fresh samples, contents of the $Al_2O_3$, $K_2O$, $Na_2O$ increase and CaO, MgO decrease in the biotite, the CaO, $K_2O$ increase and $Na_2O$ decrease in the plagioclase, the $Al_2O_3$ a little increase and $K_2O$, $Na_2O$ decrease in the orthoclase. The results of extracted cation analysis using the powder samples of each weathering grade, the CaO, $Na_2O$, $K_2O$ and MgO are highly chemical variations in rock forming minerals and positive variation show high in the weathering grade of the WW-type and CW-type. This research will be used as an importance data to establish a plan for conservation treatment of composed stone in the Mireuksaji temple stone pagoda.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.513-523
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• 2017

We evaluated the viability of phytoplankton along the salinity gradient in the flood and ebb tides of spring tide of February and the ebb tide of neap tide of March 2017 in the Seomjin River Estuary. Additional laboratory experiments were also conducted to determine the reason of the pH changes along the salinity gradient using the field natural sample in February. In field, saltwater was well mixed at downstream vertically and the salinity gradient was horizontally appeared toward upstream of freshwater zone. There were strong negative correlations between salinity and nutrient (nitrate + nitrite R=0.99, p<0.001, and silicate R=0.98, p<0.001), implying that those two nutrients of freshwater origin were gradually diluted with mixing the saltwater. On the other hands, relatively high phosphate concentration was kept in the stations of saltwater over 15 psu, indicating that it was caused by resuspended sediments of Gwangyang Bay and downstream by tidal water mixing.Among phytoplankton community structure in winter, Eucampia zodiacus have occupied to be c.a. 70 % in the most stations. Based on the field survey results for survivability of phytoplankton by phytoPAM instrument, there was positive correlations between salinity and chlorophyll a (R=0.82, p<0.001) and, salinity and active chlorophyll a (R=0.80, p<0.001), implying that the dominant marine diatom species may have significantly damaged in low salinity conditions of upstream. Also, maximum mortality rate of phytoplankton caused by low salinity shock was appered to be 75% in the upstream station. In particular, the pH in spring tides of February had tended to increase with high phytoplankton accmulated stations, suggesting that it was related with absorption of $CO_2$ by the photosynthesis of dominant diatom. In laboratory experiments, phytoplankton mass-mortality caused by low salinity shock was also occurred, which is confirmed with reducing the photosynthetic electron transport activity. Following the phytoplankton mass-mortality, bacteria abundance was significantly increased in 24 hours. As a result, the mass-proliferating bacteria can produce the $CO_2$ in the process of biodegradation of diatoms, which can lead to pH decrease. Therefore, marine phytoplankton species was greatly damaged in freshwater mixing area, depending on along the salinity gradient that was considered to be an important role in elevating and reducing of pH in Seomjin River Estuary.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.407-415
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• 1986

To obtain informations on the development of the combined granular pesticides for the simultaneous control of rice insect pests and diseases which often occur at the same time or in overlapping experiments were carried out on twelve mixture pesticides of granular type formulated by extrusion method with two fungicides and three insecticides. Each of 12 mixtures was tested for physico-chemical properties and efficacy against to rice leaf blast and brown planthoppers under the laboratory conditions. All of the mixture pesticides showed acceptable physico chemical properties as granular formulation. Most of the compounds in mixture pesticides showed a tendency to have lower stabilities than those of pesticide alone, therefore, it was necessary to add stabilizer in formulation process. Isoprothiolane combinations were found very effective against leaf blast but their control effects were similar to that of isoprothiolane alone due to its high efficacy, while probenazole-carbofuran combinations showed synergistic effects for the control of leaf blast. All of the combinations showed synergistic effects to brown planthoppers. But fenthion and 3% propoxur combinations resulted comparatively low efficacies. In the consideration of their physico-chemical properties and efficacies to rice pests, carbofuran and 6% propoxur combinations were promising combined granular pesticides for the simultaneous control of leaf blast and brown planthoppers, while fenthion and 3% propoxur combinations were not available because of their low efficacies for brown planthoppers.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.52-67
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• 1998

The investigative research on the mammalian milk purely consisted of the physiological quality of lactoferrin was conducted to reveal the antimicrobial ativity of specifically functional foods with antibiotic characteristics as a basic data in food manufacturing. Bovine lactoferrin were isolated from raw milk samples, and was digested with pepsin, trypsin and chymotrypsin. It was necessary then to separate and purify lactoferrin from bovine raw milk, and in order to analyze the antimicrobial activity of the enzyme-treated bovine lactoferrin in their required quantitative fraction. Afterwards Escherichia coli and Staphylococcus aureus was incubated in it. It was that investigated to enzyme-treated fractions molecular weight and the peptide fragment with antimicrobial effect. 1. The purity of enzyme-treated bovine lactoferrin(BLF) was tested by SDS-PAGE. As a results of 12% SDS-PAGE assay, pepsin-treated LF did not exhibited band until if reaches 14 KDa, while trypsin and chymotrypsin treated LF, known to contain the non-digestive lactoferrin exhibited band at a molecular weight of 33 KDa. 2. Bovine lactoferrin was sucessfully purified through the use of Sephadex G-50 Column. In order to assay LF through the Sephadex G-50 column chromatography, the digestive bovine lactoferrin (BLFs) was eluted with a linear gradient of 0.05% Tris-HCl. When the gel-filtration analysis, pepsin, trypsin and chymotrypsin treatments of BLF fragments was showed 2, 3, and 2 peak, respectively. The results of the HPLC analysis confirmed that had a non-digestive lactoferrin receptor, and trypsin and chymotrypsin treated BLFs has an antimicrobial effect. 3. To measure the strength of the antimicrobial effect of enzyme treated lactoferrin it was compared to the antimicrobial activity taking place at the incubated Escherichia coli and Staphylococcus aureus. This might explain the resistance of the microorganisms for peptide fragment. The pepsin-treated of bovine lactoferrin was markedly reduced by incubation of the cells. Trypsin-treated of BLF was similar to chymotrypsin-treated of BLF. However, trypsin and chymotrypsin treatments of BLFs were showed the antimicrobial effect until eight hours incubation for native bovine lactoferrin. Therefore the enzyme-treated lactoferrin have an antimicrobial effect even non-digestive lactoferrin. 4. The digestive bovine lactoferrin fragments assay was carried out by the use of Sephadex G-50 column chromatography and SDS-PAGE. The pepsin and chymotrypsin-treated fragments has a low molecular weight and trypsin-treated lactoferrin was only showed a band. It was described that characteristics of digestive protein. It appeared that there may be a relation between virulence and resistance to enzyme-treated BLF.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1546-1553
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• 2012

In this study, sorghum teas were prepared from Sorghum bicolor L. Moench subjected to different types of milling (no milling (0%), minimum milling (5%), and milling (20%)) and pan-firing times (1 to 10 minutes), and its quality characteristics were investigated. With regards to milling type, total polyphenolic, flavonoid, tannin contents, and antioxidant activities of ethanol extracts from both no milling sorghum and its tea were highest, followed by minimum milling and milling in decreasing order. Crude nitrogen content was highest in milling sorghum and its tea regardless of pan-firing time. With regards to pan-firing time, total polyphenolic, flavonoid, tannin contents, and antioxidant activities of sorghum teas increased with increasing pan-firing time regardless of milling type. The highest DPPH and ABTS radical scavenging activities were observed at a pan-firing time between 7 to 9 minutes. In contrast to ethanol extracts of pan-fried sorghum tea, antioxidant activities, chromaticity, and turbidity of hot water leaching liqueur of sorghum tea were highest in milling sorghum tea, followed by minimum milling and no milling sorghum tea.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.212-219
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• 2004

To minimize the danger of soil erosion and settle habitats earlier, afforestation, which vegetates bare slopes, is selected as an environmental recovering technology. Large portions of these areas often are suffered by a bad germination and growth inhibition of sprayed seeds. Afforested materials collected in the normal and damaged sites were not any big difference in chemical characteristics and biological response to ryegrass. But background soil of the damaged site has very low pH (3.6) and high contents of iron and aluminum compared with them of the normal sites. Both germination and root growth of ryegrass were inhibited severely in the water extracts of damaged soils, but not in the water extracts of normal sites. Groundwater collected nearby the damaged sites was very strong acidic (pH 33) and exhibited a high value of electrical conductivity and high contents of iron and aluminum. In the ground water, germinated ryegrass was scarcely grown. In Al standard solution, the root growth of ryegrass was inhibited over 50% in 0.5 mM in pH 3.5-4.5 and in 1.4 mM in pH 5.5, which seems to be related to $Al^{3+}$ activity in solution. In the ferric Fe ($Fe^{3+}$) standard solution, ryegrass growth was inhibited over 50% in the concentration of 14-19 mM in root and 23-25 mM in shoot. This strong tolerance of ryegrass to $Fe^{3+}$ might be concerned with the very low activity of $Fe^{3+}$ at pH 3.5-5.5. In contrast, ryegrass responded very sensitively to ferrous Fe ion ($Fe^{2+}$), especially in root growth: $Fe^{2+}$ concentrations corresponding to 50% growth reduction were 0.3-0.4 mM at pH 3.5-5.5 in roots. This high growth inhibition should be related to the high ion activity of $Fe^{2+}$ irrespective of different pH conditions. In conclusion, low pH and high contents of $Fe^{2+}$ and aluminum seem to be caused by pyrite and be closely related to the growth inhibition of ryegrass seeded in afforested area.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.4
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• pp.247-256
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• 2013

In this study, alginate beads containing birnessite (Bir-AB), a highly reactive oxidative catalyst for the transformation of phenolic compounds, was prepared and its 1-naphthol (1-NP) removal efficiency was investigated in a batch test. Based on scanning electron microscopy image, it can be inferred that the alginate gel cluster acts as a bridge which bind the birnessite particles together. Kinetic experiment with Bir-AB of different mixing ratios of birnessite to alginate (Bir : AG=0.25 : 1~1 : 1 w/w) indicate that pseudo-first order kinetic constants, $k(hr^{-1})$ for the 1-NP removals increased about 1.5 times when the birnessite mixing ratio was doubled. The removals of 1-NP was found to be dependent on solution pH and the pesudo-first order rate constants were increased from 0.331 $hr^{-1}$ at pH 10 to 0.661 $hr^{-1}$ at pH 4. The analysis of total organic carbon for the reaction solutions showed that a higher removal of dissolved organic carbon was achieved with Bir-AB as compared to birnessite. HPLC chromatographic analysis of the methanol extract after reaction of 1-NP with Bir-AB suggest that the reaction products could be removed through incorporation into the aliginate beads as a bound residue. Mn ions produced from the oxidative transformation of 1-NP by birnessite were also removed by sorption to Bir-AB. The Bir-AB was recovered quantitatively by simple filtration and was reused twice without significant loss of the initial reactivity.

• Journal of Environmental Impact Assessment
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• v.29 no.3
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• pp.157-181
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• 2020

Sediments from rivers, lakes and marine ports serve as end points for pollutants discharged into the water, and at the same time serve as sources of pollutants that are continuously released into the water. Until now, the contaminated sediments have been landfilled or dumped at sea. Landfilling, however, was expensive and dumping at sea was completely banned due to the London Convention. Therefore, this study applied contaminated sedimentation soil of 'Royal Palace Livestock Complex' as soil purification method. Soil remediation methods were applied to pretreatment, composting, soil washing, electrokinetics, and thermal desorption by selecting overseas application cases and domestically applicable application technologies. As a result of surveying the site for pollutant characteristics, Disolved Oxigen (DO), Suspended Solid (SS), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) exceeded the discharged water quality standard, and especially SS, COD, TN, and TP exceeded the standard several tens to several hundred times. Soil showed high concentrations of copper and zinc, which promote the growth of pig feed, and cadmium exceeded 1 standard of Soil Environment Conservation Act. In the pretreatment technology, hydrocyclone was used for particle size separation, and the fine soil was separated by more than 80%. Composting was performed on organic and Total Petroleum Hydrocarbon (TPH) contaminated soils. TPH was treated within the standard of concern, and E. coli was analyzed to be high in organic matter, and the fertilizer specification was satisfied by applying the optimum composting conditions at 70℃, but the organic matter content was lower than the fertilizer specification. As a result of continuous washing test, Cd has 5 levels of residual material in fine soil. Cu and Zn were mostly composed of ion exchange properties (stage 1), carbonates (stage 2), and iron / manganese oxides (stage 3), which facilitate easy separation of contamination. As a result of applying acid dissolution and multi-stage washing step by step, hydrochloric acid, 1.0M, 1: 3, 200rpm, 60min was analyzed as the optimal washing factor. Most of the contaminated sediments were found to satisfy the Soil Environmental Conservation Act's standards. Therefore, as a result of the applicability test of this study, soil with high heavy metal contamination was used as aggregate by applying soil cleaning after pre-treatment. It was possible to verify that it was efficient to use organic and oil-contaminated soil as compost Maturity after exterminating contaminants and E. coli by applying composting.