• 한국수산과학회지
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• 제36권5호
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• pp.463-468
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• 2003

This study observed change of survival rate, activity and foot structure of the equilateral venus (Gomphina veneriformis) exposed to cadmium. Survival rate and activity of the clam exposed to cadmium was reduced with increase of exposure duration and concentration. Change of survival rate and activity was observed in the early exposure time (7 days) in the condition of above 1 77 mg/L and 0.88 mg/L, respectively. Activity reduction of the clam exposed to cadmium seems to be caused by epidermal layer deformation, muscle fiber fragmentation and muscular layer collapse of the foot.

• 대한수의학회지
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• 제24권1호
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• pp.24-30
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• 1984

The protective effects of high levels of dietary iron, copper, zinc or protein on lead toxicity were studied In chicks. Growth retardation, reduction of feed intake, anemia and accumulation of lead in the bone and kidney were observed in chicks fed a diet containing 500mg lead as chloride per kg of feed for 42 days. Early changes due to ingested lead were inhibition of red blood cell ${\delta}$-aminolevulinic acid dehydrase at all doses and no effect of iron, copper, zinc or protein addition were observed. Tibia lead accumulation was reduced in chicks receiving additional dietary iron or zinc compared to the lead only group but increased in chicks given supplementary protein. Decreased body weight gain was overcome by supplementary zinc or protein in chicks fed lead but not by supplementary iron. Overall the results of this study show that lead poisoning can be partly reduced by providing supplementary iron, zinc or protein, but the interaction of these element remained to be elucidated.

• 환경위생공학
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• 제11권3호
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• pp.9-12
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• 1996

Polychlorinated biphenyl (PCBs) is one of major toxic pollutants in marine environments, This artificial chlorinated compound has been found in freshwater, seawater, soil, sediments and organismes living in various environments. Because of its toxicity and degradability, its uses in industrial processes have been banned after 1984 in Korea. Coastal area is an important environment for agriculture, industry, transportation, reduction of pollution loads through biogeochemical processes, cycling of nutrients and recreation. Input of pollutants from land and freshwater has been occurring through runoff, rivers and estuaries. Concentrations of PCBs were determined with GC-ECD. Concentrations of PCBs were in the range of 1.0 - 19.2 ng/g-dry weight of sediment(g-d.w.) at Ulsan, 4.5 -8,2 ng/g-d.w. at Onsan, 2.7 - 33.5 ng/g-d.w. at Masan and 4.0 - 60.7 ng/g-d.w. in Kwangyang, In Inchon area, PCBs were not detected in sediments. In sediments of Nakdong estuary, the distribution of PCBs' concentrations was 0.19 - 303 ng/g-d.w.

• 한국안전학회지
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• 제21권1호
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• pp.59-64
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• 2006

In this study, adsorption characteristics of PCBs on granular activated carbon were experimentally investigated in a batch reactor and in a fixed bed reactor. Granular activated carbon removed above 98.4% of initial concentration, 1000mg/L, of PCBs. It was estabilished that the adsorption equilibrium of PCBs on granular activated carbon was more successfully fitted by Freundlich isotherm equation in the concentration range from 1 to 1000mg/L. Because Freundlich parameter, ${\beta}$ is 0.346, removall treatment of PCBs by activated carbon accounts for the fact that toxicity reduction can be achieved through this process. Appearance time of breakthrough curve is faster with the increase flow rate and inflow concentration of liquid. The utility of granular activated carbon is enhanced with the increase of bed height and with the decrease of inflow rate.

• 한국태양에너지학회 논문집
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• 제32권spc3호
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• pp.194-198
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• 2012

Crystalline silicon solar cell remains the major player in the photovoltaic marketplace with 80% of the market, despite the development of various thin film technologies. Silicon's excellent efficiency, stability, material abundance and low toxicity have helped to maintain its position of dominance. However, the cost of silicon materials remains a major barrier to reducing the cost of silicon photovoltaics. Using the crystalline silicon wafer with thinner thickness is the promising way for cost and material reduction in the solar cell production. However, the thinner the silicon wafer is, the worse bow phenomenon is induced. The bow phenomenon is observed when two or more layers of materials with different temperature expansion coefficiencies are in contact, in this case silicon and aluminum. In this paper, the solar cells were fabricated with different thicknesses of Al layer in order to reduce the bow phenomenon. With less amount of paste applications, we observed that the bow could be reduced by up to 40% of the largest value with 120 micron thickness of the wafer even though the conversion efficiency decrease by 0.5% occurred. Since the bowed wafers lead to unacceptable yield losses during the module construction, the reduction of bow is indispensable on thin crystalline silicon solar cell. In this work, we have studied on the counterbalance between the bow and conversion efficiency and also suggest the formation of enough back surface field (BSF) with thinner Al layer application.

• Radiation Oncology Journal
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• 제33권3호
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• pp.226-232
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• 2015

Purpose: Toxicity of mucosa is one of the major concerns of radiotherapy (RT), when a target tumor is located near a mucosal lined organ. Energy of photon RT is transferred primarily by secondary electrons. If these secondary electrons could be removed in an internal cavity of mucosal lined organ, the mucosa will be spared without compromising the target tumor dose. The purpose of this study was to present a RT dose reduction in near target inner-surface (NTIS) of internal cavity, using Lorentz force of magnetic field. Materials and Methods: Tissue equivalent phantoms, composed with a cylinder shaped internal cavity, and adjacent a target tumor part, were developed. The phantoms were irradiated using 6 MV photon beam, with or without 0.3 T of perpendicular magnetic field. Two experimental models were developed: single beam model (SBM) to analyze central axis dose distributions and multiple beam model (MBM) to simulate a clinical case of prostate cancer with rectum. RT dose of NTIS of internal cavity and target tumor area (TTA) were measured. Results: With magnetic field applied, bending effect of dose distribution was visualized. The depth dose distribution of SBM showed 28.1% dose reduction of NTIS and little difference in dose of TTA with magnetic field. In MBM, cross-sectional dose of NTIS was reduced by 33.1% with magnetic field, while TTA dose were the same, irrespective of magnetic field. Conclusion: RT dose of mucosal lined organ, located near treatment target, could be modulated by perpendicular magnetic field.

• 한국응용곤충학회지
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• 제17권2호
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• pp.99-103
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• 1978

침투성 살충제 Carbofuran의 Capsule 근부처리, 액상근부주변처리 및 수면시용을 실시하였을 때 논거미(늑대거미류와 애접시거미류) 밀도에 미치는 영향을 알아보기 위해 수원과 이리에서 포장시험을 실시하였다. 1. Carbofuran의 처리에 의하여 거미의 밀도가 저하되며 관용방법인 수면처리에 비하여 근부처리의 경우 거미의 밀도가 더욱 낮었다. 2. 액상근부주변처리에 비하여 Capsule 근부처리에서 거미의 밀도가 더욱 낮었다. 3. 근부처리에서나 수면처리에서 약량이 증가함에 따라 거미밀도가 낮어졌다. 4. 무처리에서 거미밀도는 팔굉품종에서 높았고 유신품종에서 낮았으나 약제처리에서 품종간 거미밀도차이는 인정할 수 없었다. 5. 해충의 방제효과가 좋았던 Capsule 근부처리에서 거미 밀도가 낮은 이유는 식물연쇄에 의한 독성 및 살해로 고찰되었다. 6. Carbofuran의 경우 처리방법을 달리하였을 때 거미에 대한 살해를 감소시킬 수는 없을 것으로 사료된다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.108-112
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• 2012

Crystalline silicon solar cell remains the major player in the photovoltaic marketplace with 90 % of the market, despite the development of a variety of thin film technologies. Silicon's excellent efficiency, stability, material abundance and low toxicity have helped to maintain its position of dominance. However, the cost of silicon photovoltaic remains a major barrier to reducing the cost of silicon photovoltaics. Using the crystalline silicon wafer with thinner thickness is the promising way for cost and material reduction in the solar cell production. However, the thinner thickness of silicon wafer is, the worse bow phenomenon is induced. The bow phenomenon is observed when two or more layers of materials of different temperature expansion coefficiencies are in contact, in this case silicon and aluminum. In this paper, the solar cells were fabricated with different thicknesses of Al layer in order to reduce the bow phenomenon. With lower paste applications, we observed that the bow could be reduced by up to 40% of the largest value with 130 micron thickness of the wafer even though the conversion efficiency decrease of 0.5 % occurred. Since the bowed wafers lead to unacceptable yield losses during the module construction, the reduction of bow is indispensable on thin crystalline silicon solar cell. In this work, we have studied on the counterbalance between the bow and conversion efficiency and also suggest the formation of enough back surface field (BSF) with thinner Al paste application.

• 식품보건융합연구
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• 제4권2호
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• pp.7-11
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• 2018

Salinity is one of the major and increasing problems in irrigated agriculture in Pakistan. Salinity stress negatively affects the growth and yield of plants guar (Cyanoposisa tetragonoloba). This experiment was conducted to evaluate the effects of ($4dSm^{-1}+13.5(mmol\;L^{-1})^{1/2}$, $5dSm^{-1}+25(mmol \;L^{-1})^{1/2}$, $5dSm^{-1}+30(mmol\;L^{-1})^{1/2}$, $10dSm^{-1}+25(mmol\;L^{-1})^{1/2}$ and $10dSm^{-1}+30(mmol \;L^{-1})^{1/2}$) on biomass yield of guar against salinity tolerance. Maximum biomass yield ($54.50gpot^{-1}$) was produced by $4dSm^{-1}+13.5(mmol\;L^{-1})^{1/2}$ treatment. Biomass produce was reduced with the increase of the salts toxicity. Minimum biomass yield ($30.17gpot^{-1}$) was attained under $10dSm^{-1}+30(mmol \;L^{-1})^{1/2}$. $5dSm^{-1}+25(mmol\;L^{-1})^{1/2}$ treatment exhibited improved outcome i.e. the least diminution % over control (18.66). Salinity cum sodicity showed staid effect on the growth reduction from 18.66% to 44.64%. This reduction fissure was impacted by the toxic effect of salinity and sodicity on Guar growth. Salinity- sodicity behaved toxic impact on the growth reduction from 18.66% to 44.64%. Based on the findings, guar (Cyanoposisa tetragonoloba) grows better at $4dSm^{-1}+13.5(mmol \;L^{-1})^{1/2}$ treatment.

• Korean Journal of Acupuncture
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• 제22권3호
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• pp.165-174
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• 2005

Objective : The objective of this study is to investigate the inhibitor effects of an traditional oriental herb, Sophora flavescens on the hepatic and renal side effects of chemotherapy by using B16-BL6 melanoma-injected C57BL6 mouse tumor model. Methods : In this study, the effects of an traditional oriental herb, Sophora flavescens, on the side effects of chemotherapy were studied using B16 melanoma-injected C57BL6 mouse tumor model. Results : Sophora flavescen has significant effect on the reduction of the side effects of chemotherapy. Sophora flavescen recovered the reduction of WBC and RBC during cisplatin chemotherapy. Water extract of Sophora flavescens significantly inhibited cisplatin-induced increase of serum blood urea nitrogen (BUN) which is a good indicator of renal toxicity. Sophora flavescens extract does not decrease the anti-tumor activity of cisplatin showing that it can selectively inhibit side effects of anticancer drugs preserving beneficial effort. Conclusion : Theses results suggest a possibility that Sophora flavescens extract can be used for cancer patients for the reduction of the side effects and improving the quality of life during chemotherapy of cancer patients.