• Korean Journal of Microbiology
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• v.25 no.2
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• pp.110-116
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• 1987

As a pary of investgation on effective accumulation of cadmium in yeast cells, effect of surfactant was studied on intracellular accumulation of cadmium in extremely cadmium-tolerant yeast, Hansenula anomala B-7. Cadmium accumulation was enhanced up to approximately 40% by the addition of non-ionic surfactant, Triton X-100 and its optimal concentration was found to be 0.1-0.2%. Furthermore, optimum conditions for intracellular accumulation of cadmium were at $40^{\circ}C$ and initial pH 6.0 for 48 hours under shaking culture.

• Asian Journal of Turfgrass Science
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• v.13 no.4
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• pp.201-212
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• 1999

In use of pesticides in golf courses has been increased steadily. Environmental concern as well as decrease in efficiency led the turfgrass management into an alternate approach of using beneficial microorganism to deal with turfgrass pests. This study was focused on the use of such microorganisms for improving cultural environment and minimizing the use of pesticides. Microorganisms antagonistic to turfgrass diseases were applied to zoysiagrass fairways and creeping bentgrass greens in Yusung country club. Tharch accumulation, disease occurrence, and other cultural environments were compared among the combinations of microorganisms and suppliemental N applications. The application of microorganisms antagonistic to turfgrass diseases improved turf resiliency. Thatch thickness was 3.03cm in the control plot but it was 2.11cm in plots treated by microorganisms, indicating significant effects of microorganism application on reduction of thatch accumulation. Number of microorganism that can decompose of cellulose was higher at the plots treated with useful microbial products and it was considered that existence of higher population of microorganisms resulted in reduction of thatch accumulation. In the evaluation of relationship between thatch accumulation and disease occurrence, greater thatch accumulation was observed at the golf courses which have been frequently infested by large patch. However, the rate of thatch accumulation varied among surveyed golf courses regardless of the year of turf establishment. Therefore, management practice which can be effective for reduction of thatch could result in large patch suppression. The application of microorganisms on the established turfgrasses reduced the occurrence rate of pythium blight and yellow path diseases, whereas occurrence of brown patch and dollar spot increased.

• Environmental Engineering Research
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• v.19 no.3
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• pp.241-245
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• 2014

The As accumulation in part of roots, shoots, husks and grains of rice plants was significantly decreased with the increasing dosage of kaolin addition from 0.5% to 10% w/w. Kaolin addition could reduce As accumulation in rice plants, which mainly could be attributed to the formation of stable crystalline Al oxides bound As that decreased the available As in soil with decreased As accumulation in rice plants. The pH values of the soils did not change significantly when amended with kaolin. The pH values of the soils was neural that proper to adsorb of arsenic with $Al_2O_3$. Arsenic tends to adsorb with $Al_2O_3$ at acid neutral pH and with desorbing at alkaline pH. The dry weight of rice plant was significantly increased with the increasing dosage of kaolin addition from 2.5% to 10% w/w. The highest dry weight of rice plants was 6.67 g/pot achieved at kaolin addition of 10% w/w with about 13% increasing over the control, which was probably attributed to the highest As concentration formation with kaolin at this dosage. The results of this study indicated that kaolin has the potential to reduce As accumulation in rice plants and enhance the dry weight of rice plants.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.2
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• pp.45-58
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• 2015

The aim of this study is to find out major accumulation zones through field survey and moving route tracking trials on floating debris of Nakdong River. It also identified composition and accumulated amount of the floating debris by sample survey for accumulation zones. As a result, total 5 accumulation zones were selected from the midstream and downstream of the Nakdong River. There was a large amount of floating debris, including vegetation debris, in the accumulation zones. And two accumulation zones located in the downstream region, it is much more likely to flow into the ocean along river. From the sample survey on the major accumulation zones, more than $40{\ell}$ of floating debris were collected including vegetation and artificial debris. As a result of composition analysis for artificial debris, plastic(49%) and styrofoam(36%) were the majority in number. The present study is expected to help to plan an efficient pre-collecting activity and to reduce floating debris flowing into the ocean from the Nakdong River.

• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.142-148
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• 1997

This study was performed to develop the biological treatment technology of wastewater polluted with heavy metals. Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri possessing the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The effect of competing ions and metabolic inhibitors on heavy metal accumulation in the cells was investigated. Heavy metal accumulation into cells was drastically decreased in the presence of competing cation, $Al^{3+}$, and also decreased, at a lesser extent, in the presence of competing anions, $CO_3\;^{2-}$ and $PO_4\;^{2-}$. But heavy metal accumulation was not influenced generally in the presence of the other rations and anions. The accumulation of Cd, Zn or Cu by Cd-, Zn- or Cu-tolerant microorganism was remarkably decreased in the presence of metabolic inhibitors, but the accumulation of Pb by Pb-tolerant microorganism was little affected in the presence of metabolic inhibitors. These results suggested that the accumulation of Cd, Zn or Cu by Cd-, Zn- or Cu-tolerant microorganism was concerned with the biological activity depending on energy, and the accumulation of Pb by Pb-tolerant microorganism depended on not the biological activity but the physical adsorption on the cell surface. Each heavy metal-tolerant microorganism also exhibited some ability to accumulate the other heavy metals in solution containing equal concentrations of cadmium, lead, zinc and copper, when measured at 48 hours after inoculation of the microorganisms, but the accumulation rates were somewhat low as compared to the accumulation rates of heavy metal fitting to each tolerance. These results suggested that the accumulation of each heavy metal by each heavy metal-tolerant microorganism was a selective accumulation process.

• Journal of Electrical Engineering and Technology
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• v.6 no.6
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• pp.824-828
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• 2011

Transmission line analysis of the surface a cumulation layer in injection-enhanced gate transistor (IEGT) is presented for the first time, based on per-unit-length resistance and conductance of the surface layer beneath the gate of IEGT. Lateral electric field on the accumulation layer surface, as well as the electron current injected into the accumulation layer, is governed by the well-known wave equation, and decreases as an exponential function of the lateral distance from the cathode. Unit-length resistance and conductance of the layer are expressed in terms of the device parameters and the applied gate voltage. Results obtained from the experiments are consistent with the numerical simulations.

• Korean Journal of Oriental Medicine
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• v.9 no.2
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• pp.45-54
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• 2003

Obesity is caused by unbalance of energy intake and expenditure, which results in extra accumulation of adipose tissue. Obesity is directly related to metabolic diseases such as diabetes, hyperlipidemia, fatty liver and so on. To investigate the anti-obesity effects of Scutellariae Radix, 70% EtOH extract and water extract of it were tested by in vitro and in vivo studies of fat accumulation. 3T3-L1 preadipocyte cell line was used in a in vitro study of fat accumulation. After 3T3-L1 cells were induced to differentiate into adipocytes, S. radix extract were added and fat accumulation was measured by oil red O staining. In vivo study showed that weight and epididymal/ retro-peritoneal adipose tissues were significantly reduced in mice fed Scutellariae Radix extract compared with control group. Especially, mice fed Scutellariae Radix extract showed reduced serum triglyceride and glucose levels. When adipose tissues were analyzed by microscope, mean adipocyte size was significantly reduced in Scutellariae Radix extract-fed mice. Therefore, this study showed inhibitory effects of Scutellariae Radix on in vitro and in vivo fat accumulation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.2
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• pp.108-113
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• 2022

Arsenic (As) uptake and accumulation from agricultural soil to rice vary depending on the soil environmental conditions such as soil pH, redox potential, clay content, and organic matter (OM) content. Therefore, these factors are important in predicting changes in the uptake and accumulation of As in rice plants. Here, we studied the chemical properties of As-contaminated and/or rice straw compost (RSC)-treated soils, the growth responses of RSC-applied rice plants under As-contaminated soils, the changes in As content of soil, and the relationship between As uptake and accumulation from the RSC-treated soils to the rice organs under As-contaminated soils. Rice plants were cultivated in 30 mg kg^-1 As-contaminated soils under three RSC treatments: 0 (control), 12, and 24 Mg ha^-1. No significant differences were indicated in the chemical properties of pre-experimental (before transplanting rice seedling) soils, with the exception of EC, OM, and available P₂O₅. As the treatment of RSC under 30 mg kg^-1 As-contaminated soils increased, EC, OM, and available P₂O₅ increased proportionally in soil. Increased soil RSC under As-contaminated soils increased shoot dry weight of rice plants at harvesting stage. As content in roots increased proportionally with RSC content, whereas As content in shoots decreased under As-contaminated soil at all stages of rice plants. Nevertheless, As accumulation were significantly decreased in both roots and shoots of RSC-treated rice plants than those in the plants treated without RSC. These results indicate that the use of RSC can mitigate As phytotoxicity and reduce As accumulation in rice plants under As-contaminated soils. Therefore, RSC can potentially be applied to As-contaminated soil for safe crop and forage rice production.

• Journal of the Korean Society of Combustion
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• v.15 no.4
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• pp.58-64
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• 2010

Spontaneous ignition tests of five different coals with non-iso-thermal and iso-thermal test method based on the standard test procedure of NF T20-036 were carried. These five coals included the 2 low rank coals and 3 bituminous coals. Test results showed that the ignition temperatures of all coals at the iso-thermal conditions were higher than that of non-isothermal condition, and those of low rank SM and BR coal in both nonisothermal and isothermal conditions were lower than bituminous AN and CN coals. The chemical species of coals such as oxygen and hematite also plays an important role in enhancing the ignition rate that the ignition temperature of SM coal was lowered. The heat accumulation tendency of five coals inside outdoor stack pile was monitored with emphasis on the change in the temperature of the coal depth in stack pile. In case of low rank BR coal, its temperature inside coal stack pile due to the rate of high heat accumulation and oxidation was $59^{\circ}C$ compared to $51^{\circ}C$ for other SW bituminous coal. And the heat accumulation rate inside coal stack piles was increased with increased the Cp value which it was defined as the specific heat of coal at constant pressure, whereas other factors such as thermal diffusivity and conductivity of coal relatively had less effect on heat accumulation.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.7
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• pp.1-7
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• 2010

The device performances of accumulation-mode Pi-gate pMOSFETs with different fin widths have been characterized at high operating temperatures. The device fin height is 10nm and fin widths are 30nm, 40nm, and 50nm. The variation of the drain current, threshold voltage, subthreshold swing, effective mobility, and leakage current have been investigated as a function of operating temperatures. The drain current at high temperature is slightly larger than at room temperature. The variation of the threshold voltage as a function of the operating temperature is smaller than that of the inversion-mode MOSFETs. The effective mobility is decreased with the increase of operating temperature. It is observed that the effective mobility is enhanced as the fin width decreases.