• Proceedings of the KWS Conference
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• 2002.10a
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• pp.612-619
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• 2002

The dynamic behavior of Al-Mg alloys plasma was very unstable and this instability was closely related to the unstable motion of keyhole during laser irradiation. The keyhole fluctuated both in size and shape and its fluctuation period was about 440 ${\mu}{\textrm}{m}$. This instability has been estimated to be caused by the evaporation phenomena of metals with different boiling point and latent heats of vaporization. Therefore, the authors have conducted the spectroscopic diagnostics of plasma induced in the pulsed YAG laser welding of Al-Mg alloys in air and argon atmospheres. In the air environment, the identified spectra were atomic lines of Al, Mg, Cr, Mn, Cu, Fe and Zn, and singly ionized Mg line, as well as strong molecular spectrum of AlO, MgO and AIH. It was confirmed that the resonant lines of Al and Mg were strongly self-absorbed, in particular in the vicinity of pool surface. The self-absorption of atomic Mg line was more eminent in alloys containing higher Mg. These facts showed that the laser-induced plasma was relatively a low temperature and high density metallic vapor. The intensities of molecular spectra of AlO and MgO were different each other depending on the power density of laser beam. Under the low power density irradiation condition, the MgO band spectra were predominant in intensity, while the AlO spectra became much stronger in higher power density. In argon atmosphere the band spectra of MgO and AlO completely vanished, but AlH molecular spectra was detected clearly. The hydrogen source was presumably the hydrogen solved in the base Metal, absorbed water on the surface oxide layer or H$_2$ and $H_2O$ in the shielding gas. The temporal change in spectral line intensities was quite similar to the fluctuation of keyhole. The time average plasma temperature at 1 mm high above the surface of A5083 alloy was determined by the Boltzmann plot method of atomic Cr lines of different excitation energy. The obtained electron temperature was 3, 280$\pm$150 K which was about 500 K higher than the boiling point of pure aluminum. The electron number density was determined by measuring the relative intensities of the spectra1lines of atomic and singly ionized Magnesium, and the obtained value was 1.85 x 1019 1/㎥.

• Journal of Wetlands Research
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• v.9 no.1
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• pp.69-78
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• 2007

Constructed wetlands and other aquatic systems have been successfully used for waste and wastewater treatment in either temperate or tropical regions. To treat waste or wastewater in a sustainable manner, the integrated eco-engineering designs are explained in this paper with 2 case studies: (i) a combination of vertical-flow constructed wetland (CW) with plant irrigation systemfor fecal sludge management and (ii) integrated CW units with landscaping at full-scale application for domestic wastewater treatment. The pilot-scale study of fecal sludge management employed 3 vertical-flow CW units, each with a dimension of $5{\times}5{\times}0.65m$ (width ${\times}$ length ${\times}$ media depth) and planted with cattails (Typha augustifolia). At the solid loading rate of 250 kg total solids (TS)/$m^2.yr$ and a 6-day percolate impoundment, the CW system could achieve chemical oxygen demand (COD), TS and total Kjeldahl nitrogen (TKN) removal efficiencies in the range of 80 - 96%. The accumulated sludge layers of about 80 - 90 cm was found at the CW bed surface after operating the CW units for 7 years, but no clogging problem has been observed. The CW percolate was applied to 16 irrigation Sunflower plant (Helianthus annuus) plots, each with a dimension of $4.5{\times}4.5m$ ($width{\times}length$). In the study, the CW percolate were fed to the treatment plots at the application rate of 7.5 mm/day but the percolate was mixed with tap water at different ratio of 20%, 80% and 100%. Based on a 1-year data of 3-crop plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increasing in CW percolate ratios. The highest plant biomass yield and oil content of 1,000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower is found. In addition to the pilot-scale and field experiments, a case study of the integrated CW systems for wastewater treatment at Phi Phi Island (a Tsunami-hit area), Krabi province, Thailand is illustrated. The $5,200-m^2$ CW systems on Phi Phi Island are not only for treatment of $400m^3/day$ wastewater from hotels, households or other domestic activities, but also incorporating public consultation in the design processes, resulting in introducing the aesthetic landscaping as well as reusing of the treated effluent for irrigating green areas on the Island.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.760-763
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• 2012

This study was conducted to investigate foliar treatment effects of organic agricultural materials for the environmentally-friendly cultivation of grape. The organic materials applied were chitosan, wood vinegar (pyroligneous acid), amino acid solution, and ginkgo leaf extract. All the organic materials were relatively strong acidic ranging lower than pH 4.6. when comparing with other organic materials, amino acid solution contained relatively high contents of selected plant nutrients, such as N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn. As comparison of selected soil properties in the grape cultivating field, soil pH values were lower at the harvest stage than at the first stage of grape growing (before treating the organic materials), and electrical conductivity (EC) and soil organic matter content were higher at the harvest stage in the all plots. The concentrations of available phosphorus increased in most of the plot soils except in control plot (conventional treatment). The concentrations of exchangeable K decreased in the plot treated with ginkgo leaf extract and the control plot. The exchangeable Mg concentrations decreased in soils of all the plots. On the other hand, the concentrations of N and K in the grape leaves were higher with the treatments of chitosan and amino acid solution, P concentrations were higher with the applications of chitosan, wood vinegar and amino acid solution, and Ca and Mg concentrations were higher with chitosan and amino acid solution treatments, respectively, than with others. The yields of grape were higher, $1,581{\sim}1,583kg\;10a^{-1}$, in the control and wood vinegar treatment plots than others. Sugar contents of grape were not different among all the plots.

• Food Science and Preservation
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• v.12 no.5
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• pp.476-481
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• 2005

This study was carried out to analyze the components of the Angelica dahurica root for the studies of the physiological function. General components of A. dahurica root were 71.7% moisture, 10.6% carbohydrate, 9.3% crude protein, 6.6% crude ash and 1.9% crude fat. The content of reducing sugar was 1,850 mg/100 g. The total amount of free sugar was 80 mg/100 g, in which 19.3 mg/100 g fructose, 27.8 mg/100 g glucose, 28.4 mg/100 g sucrose and 4.5 mg/100 g maltose were present. In the results of mineral analysis, the content of K was the highest(2,145.03 mg/100 g) followed by 286.35 mg/100 g Mg and 145.23 mg/100 g Ca. The total amount of hydrolyzed amino acid was 71.68 mg/100 g, in which 20.98 mg/100 g essential amino acid and 50.70 mg/100 g of non-essential amino acid were present. Among them, proline(11.74 mg/100 g) was the highest. Total free amino acids were contained 17.04 mg/100 g, in which 6.67 mg/100 g of essential amino acids and 10.37 mg/100 g of non-essential amino acids were present. Among them alanine(5.96 mg/100 g) was the highest. Total content of amino acid derivatives was 3.37 mg/100 g.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.3-11
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• 1999

The effects of major cations in soils, soil : extractant ratio, and EDTA : lead stoichiometric ratio on the extraction efficiency of lead using EDTA were studied for 4 different actual lead-contaminated soils and one artificially lead-contaminated soil. Extraction of lead from the lead-contaminated soil was not affected by a soil : extractant ratio as low as 1 : 3 but instead was dependent on the quantity of EDTA present. Results of the experiments showed that the extraction efficiency for each soil was different, but if sufficiently large amount of EDTA was applied, all the lead may be extracted except for a soil from lead mining area. The differences in extraction efficiencies nay be due to the major cations present in soils which may compete with lead for active sites on EDTA. The total molar amount of major cations extracted was as muck as 20 times more than the added molar amount of EDTA. For some of the soils tested, the extraction efficiency of lead may be affected by being occluded in the Fe and Mn oxides present in the soil. While major cations present in the soil may be one of the factors affecting lead extraction efficiency, the type of lead species present may also play a role. When these factors affect severely, the using of EDTA to extract lead from lead-contaminated soil might be non-effective method.

• Journal of Life Science
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• v.20 no.9
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• pp.1385-1393
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• 2010

Three mold strains, Aspergillus oryzae (AOFAG), Aspergillus kawachii (AKFAG), and Monascus purpureus (MPFAG) were used for fermentation of Angelica gigas Nakai powder. The contents of polyphenolic compounds, flavonoids, minerals, decursin and decursinol angelate and the activities of DPPH (${\alpha},{\alpha}'$-diphenyl-$\beta$-picrylhydrazyl) free radical scavenging, reducing power, and tyrosinase were measured. The highest contents of phenolic compound and flavonoid were NFAG at 2.78% and MPFAG at 1.18%, respectively. Major minerals were K, Mg, Fe, Na and Ca. Decursin and decursinol angelate were the major ingredients of Angelica gigas according to HPLC analysis. Decursin area was higher in all fermented Angelica gigas than in NFAG. The activities of free radical scavenging and tyrosinase were stronger in all fermented Angelica gigas than NFAG. However, the Fe/Cu reducing powers were stronger in NFAG than all fermented Angelica gigas. Overall, these results may provide the basic data needed to understand the biological activities and chemical characteristics of Angelica gigas fermented by mold for the development of functional foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1394-1399
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• 2014

Quality characteristics of radish treated with red clay-processed materials (RCPM) were investigated. Two different types of treatments using RCPM including a control were farm-raised in identical environments. General components, texture, nutrients, and antioxidant activities were performed. For general components analysis, total amounts of crude fat and ash were higher in radish treated with RCPM than in control. RCPM-treated radish showed higher contents of minerals (P, Mg, K, Zn, Mn, and Na) and vitamins (vitamin C, thiamin, and riboflavin) than those of control. RCPM-treated radish exhibited higher DPPH radical scavenging activities and total polyphenol contents than those of control, indicating higher antioxidant activities of radish raised by RCPM. In the textural analysis following refrigeration for 4 weeks, RCPM-treated samples showed a more stable texture and higher hardness values than those of control. Therefore, these results indicate that RCPM can be used to produce high-value radish of premium quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.27-34
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• 2016

Garlic has drawn attention as a food material for its anti-oxidative and anti-inflammatory properties as well as for prevention and treatment of cancer. In order to increase efficiency, various aging methods for garlic have been attempted. In particular, thermally processed garlic is known to have higher biological activities due to its various chemical changes during heat treatment. Therefore, in this study, we investigated the anti-oxidative effects of garlic extracts aged at low temperature ($60{\sim}70^{\circ}C$). In the results, 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis (3-ethylbenzo-thiazoline-6-sulfonate) radical scavenging activities and ferric reducing ability of low temperature-aged garlic (LTAG) were similar to those of raw garlic. LTAG also showed decreased lipopolysaccharide (LPS)-induced production of reactive oxygen species, although there were not significant differences among samples. In addition, xanthine oxidase activity was inhibited by LTAG; the 15 days and $60^{\circ}C$ extract showed outstanding inhibition compared with the others. To understand the molecular mechanisms behind the anti-oxidative activity of LTAG, we performed quantitative real-time PCR analysis. The 30 days and $70^{\circ}C$ extract upregulated mRNA expression of antioxidant enzymes such as Cu/Zn-superoxide dismutase (SOD), Mn-SOD, glutathione peroxidase, and catalase in LPS-stimulated RAW 264.7 cells. This result indicates that LTAG can be a functional food as a nature antioxidant and antioxidant substance.

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1583-1587
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• 2016

The purpose of this study was to investigate the effects of fertilizer application on the content of functional materials, such as fatty acids and organic acids in perilla leaves. (1) As compared to the controlled with Ammonium sulfate fertilizer, the yield of Perilla frutescens leaves increased by 7.3% and 12.8% of biomass at 2000 and 1000 times liquid respectively, but decreased by 7.6% at 500 times. The lipid and protein contents of perilla leaves were higher than those of Portunus trituberculatus liquid at 1000 times. The average contents of minerals (mg/100g) were as follows; K (638.4) > Ca (561.6) > P (145.4) > Mg (133.5) > Fe (36.2) > Zn (1.9) > Mn (1.6) > Na (1.4 mg). However, the correlation between the controlled with P. trituberculatus liquid was relatively low. (2) The fat-soluble vitamin E content of P. frutescens leaves was 3.4, 3.9, 3.3, and 3.9 mg in the controlled with liquid by 500, and 1000, 2000 times respectively; Vitamin A contents were 6.4, 8.9, 10.9, and 8.5 mg respectively, which was more than twice as much as the corresponding vitamin E content. The water soluble vitamin C contents were 177.9, 172.6, 195.2, and 163.5 mg respectively. (3) Amino acid contents of P. frutescens leaves in 100 g of fresh weight were 3821.7 mg in the controlled with Ammonium sulfate fertilizer and 3918.8, 4054.0, and 4005.4 mg in the controlled with P. trituberculatus liquid at 2,000, 1000, 500 times respectively. Amino acid contents of each controlled group with P. trituberculatus liquid above were as small as 2.5~6.1%, and these contents of amino acid were as follows: Glutaminic acid > Aspartic acid > Leucine > Arginine > Phenylalanine. In further study, it is necessary to develop an effective microorganism and a variety of amino acid fertilizer to supplement the study on new manufacturing.

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1541-1554
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• 2016

To understand the characteristics of vanadium leaching from soils formed by the weathering of basalts, paleo soil at Gosan, Jeju Island, Korea, and several present-day soils from neighboring areas were collected. Leaching experiments were carried out by two approaches: 1) batch experiments under various geochemical conditions (redox potential (Eh) and pH) and 2) continuous leaching experiments under conditions similar to those of natural environments. From the batch experiments, leached vanadium concentrations were highest under alkaline (NaOH) conditions, with a maximum value of $2,870{\mu}g/L$, and were meaningful (maximum value, $114{\mu}g/L$) under oxidizing ($H_2O_2$) conditions, whereas concentrations under other conditions (acidic-HCl, $neutral-NaHCO_3$, and $reducing-Na_2S_2O_3$) were negligible. This indicated that the geochemical conditions, in which soil-water reactions occurred to form groundwater with high vanadium concentrations, were under alkaline-oxidizing conditions. From the continuous leaching experiments, the pH and leached vanadium concentrations of the solution were in the ranges of 5.45~5.58 and $6{\sim}9{\mu}g/L$, respectively, under $CO_2$ supersaturation conditions for the first 15 days, whereas values under $O_2$ aeration conditions after the next 15 days increased to 8.48~8.62 and $9.7{\sim}12.2{\mu}g/L$, respectively. Vanadium concentrations from the latter continuous leaching experiments were similar to the average concentration of groundwater in Jeju Island ($11.2{\mu}g/L$). Furthermore leached vanadium concentrations in continuous leaching experiments were highly correlated with pH and Al, Cr, Fe, Mn and Zn concentrations. The results of this study showed that 1) alkaline-oxidizing conditions of water-rock (soil) interactions were essential to form vanadium-rich groundwater and 2) volcanic soils can be a potential source of vanadium in Jeju Island groundwater.