• Journal of Environmental Science International
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• v.10 no.6
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• pp.437-444
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• 2001

The characteristic features of surface ozone concentration and the forecasting procedure of high ozone days have been studied. The ozone concentration was continuously measured during 3 years (1997~1999) at air quality monitoring stations in five major cities in Korea. The diurnal variation of surface ozone concentration on high ozone days is characterized by low ozone concentration at night. The ozone concentration Increases continuously after sunrise, In reach a peak at 1500~1600 LST. Thereafter it decreases steadily to a low concentration at sunset. The diurnal and annual maximum of the surface ozone concentration at Seoul were observed in May and June, respectively. The favorable synoptic condition for the high ozone day is divided into 4 different synoptic weather patterns: a high-pressure system from the Sea of Okhotsk, the Pacific subtropical high extending westward, a moving high-pressure system covering the Korean peninsula. and a synoptic system In front of a typhoon. Most of high ozone days occur under the high pressure system in Korea.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.269-274
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• 2013

To further our understanding of sugar accumulation in 'Shiranuhi' mandarin [(C. unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulate], we investigated the patterns of sugar uptake in juice sacs exposed to different concentrations of sucrose, fructose and glucose in vitro. Data was also collected on the change in weight and shape of the in vitro juice sacs over time. Soluble solids content, sugar content and acidity content were highest at 20% sucrose, fructose and glucose solution content; while fructose content was highest at 5% sucrose concentration. Furthermore, the juice sac's fresh weight was highest at 5% sucrose and lowest at 20% fructose content. The shape of the juice sacs also differed in different sugar concentration and type. Overall, sucrose, fructose and glucose content in juice sacs increased with the sugar concentration. These results suggest that sugar translocation into juice sacs is actively induced by high sugar concentration in the medium. Thus, it can be concluded that sugar and acid accumulation in juice sacs increased with sugar concentration in vitro culture.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.25-31
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• 2000

In order to assess the accumulation levels of cadmium and other metals(Zn, Cu, Ca and Fe) in fish bodies, an experimental study was performed by raising fry of "Oryzias latipes" in the water containing cadmium 0.03 ppm, cadmium 0.03 ppm + zinc 0.03 ppm and in the tap water(control group) were made. In the results the concentration of Cd in fish bodies were increased with advancing exposure time in Cd 0.03 ppm treated group and 0.03 ppm + Zn 0.03 ppm treated group, but there was no significantly different between both groups with Cd concentration in each week. The concentration of Zn in fish bodies was no changed with advancing exposure time in control group and Cd 0.03 ppm + Zn 0.03 ppm treated group were significantly different from control and Cd 0.03 ppm treated group. The concentration of Cu, Ca and Fe in fish bodies were increased with advancing exposure time, and control group was higher than any other groups. Simple correlation analysis showed that the positive correlation between Cd and Zn, Cu and Ca, Fe, Ca and Fe, but Cd was negative correlation with Cu, Ca and Fe. In conclusion, we investigated a tendency that the concentration of Cd and Zn in fish bodies tended to increase with the lapse of time, but Cu was unchanged and those of Ca and Fe were decreased in administrating the trace dose of Cd and Zn in water. in water.

• Environmental Analysis Health and Toxicology
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• v.24 no.3
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• pp.251-259
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• 2009

This study was conducted to measure the concentration of PCBs in pine needles and soil in urban (Seoul, many artificial sources of PCBs), semi-rural (Anseong, small town located below Seoul in wind direction) and rural areas (Jincheon, rarely artificial sources of PCBs) in which the artificial production amount of PCBs are different. The total PCBs concentrations in pine needles, which did not show big difference in three sampling sites, were 107.5 pg/g (urban), 94.8 pg/g (semi-rural) and 78.8 pg/g (rural) respectively. The low chlorinated PCBs were major component in pine needles and the PCBs congener concentration profile of each sampling area were similar each other, and the octanol-air partitioning coefficient, Koa, highly correlated with the PCBs concentrations in pine needles. The total PCBs concentrations in soil which did show big difference in three sampling sites, were 830.0 pg/g (urban), 314.1 pg/g (semi-rural) and 136.5 pg/g (rural) respectively. The high chlorinated PCBs were major component in soil and the PCBs congener concentration profile of each sampling area were similar each other. There was no similarity between the PCBs concentration of pine needles and those of soil at each site, because of the different mechanism of deposition and volatilization processes of PCBs. The total PCBs concentrations of 2009 became 12.9 times lower than those of 2001. The reduce rate of PCB 28 was the greatest.

• Journal of Electrochemical Science and Technology
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• v.5 no.4
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• pp.115-127
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• 2014

Cd-Pb thin films were electrodeposited from a diluted chloride solution using stainless steel rotating disc electrode. The linear sweep voltammograms of the single metallic ions show that electrodeposition of these ions was mass transfer control due to the plateau observed for different rotations at concentration (50 and 200 ppm). The voltammograms of binary system elucidate that electrodeposition process always start at cathodic potential located between the potential of individual metals. Currents transients measurements, anodic linear sweep voltammetry (ALSV) and atomic force microscopy (AFM) were used to characterize the electrocryatalization process and morphology of thin films. ALSV profiles show a differentiation for the dissolution process of individual metals and binary system. Two peaks of dissolution Cd-Pb film were observed for the binary system with different metal ion concentration ratios. The model of Scharifker and Hills was used to analyze the current transients and it revealed that Cd-Pb electrocrystalization processes at low concentration is governed by three-dimensional progressive nucleation controlled by diffusion, while at higher concentration starts as a progressive nucleation then switch to instantaneous nucleation process. AFM images reveal that Cd-Pb film electrodeposited at low concentration is more roughness than Cd-Pb film electrodeposited at high concentrated solution.

• Korean Journal of Acupuncture
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• v.21 no.1
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• pp.95-102
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• 2004

Objective : This study is effects of Jungwan$(CV_{12})$ and Bisu$(BL_{20})$ acupuncture on serum glucose and lipid composition were investigated in high fat diet induced diabetic rat. Results : Plasma glucose, free fatty acids and $\beta-lipoprotein$ concentration showed a high reduction in acupuncture groups compared to those of control group and in the acupuncture groups, Jungwan$(CV_{12})$ acupuncture groups showed a low values than Bisu$(BL_{20})$ acupuncture group. Plasma triglyceride and LDL-cholesterol concentration showed a tendency to decrease in the acupuncture groups, however these values showed no significantly different among acupuncture groups. Total cholesterol concentration showed a high reduction in acupuncture groups and in acupuncture groups, Jungwan$(CV_{12})$ acupuncture groups showed a lower values than Bisu$(BL_{20})$ acupuncture group. HDL-cholesterol concentration showed a higher values in all acupuncture groups than control group, however these values no significantly different in all acupuncture groups.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.349-354
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• 2012

To evaluate the biological response of sea squirt Halocynthia roretzi with different body size to heavy metals and its suitability for ecotoxicity assays, the effects of Cr, Cu and Zn on its clearance and oxygen consumption rates were investigated. Clearance and oxygen consumption rates of H. roretzi with various body sizes were calculated at different metal concentrations. Both clearance and oxygen consumption rate were negatively correlated with body sizes. Clearance rate of H. roretzi decreased gradually with increasing concentration of heavy metal, the decreasing rate was in an order of Cr>Cu>Zn. The oxygen consumption rate first increased at low metal concentration (below $100{\mu}g\;L^{-1}$) and then decreased rapidly with increasing metal concentrations. The decreasing rate was in an order of Cu>Cr=Zn. There was a trend that the clearance rate and oxygen consumption rate decreased drastically under a concentration of $400{\mu}g\;L^{-1}$, and then decreased smoothly when the metal ion concentration increased continually. So the oxygen consumption and clearance rate at a concentration of $400{\mu}g\;L^{-1}$ Cu could be thought as a suitable biological tool for exotoxicology analysis.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.5
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• pp.581-587
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• 2014

Sediment basin that is typical facility installed for development business to prevent soil erosion has low removal efficiency and therefore, it causes complaints from the residents and has a bad effect on ecosystem. Thus there is a limit to control soil erosion using the existing design methods of sediment basin, so the purposes of this study is providing suitable design factors for sediment basin with regarding soil characteristic of development areas and analysing sedimentation characteristic by inflow concentration changes. The results, for analyzing the sedimentation characteristic by soil concentrations within approximately 2,000 ~ 20,000 mg/L of initial SS concentration, indicated similar sedimentation trends for same soil in the supernatant regardless of initial concentrations. However, for different soil characteristic (percent finer), there are different results in sedimentation rate and concentrations of the supernatant. Thus it is recommended that sediment basin to prevent soil erosion during construction should be designed based on retention time derived from soil sedimentation experiments regardless of inlet concentration. In addition, installing the soil erosion prevention facility at the back to satisfy effluent water quality should be considered to minimize soil erosion effectively.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.165-169
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• 2018

An assessment for determining N-16 activity concentrations during the operation condition of Bangladesh Atomic Energy Commission TRIGA Research Reactor was performed employing several governing equations. The radionuclide N-16 is a high energy (6.13 MeV) gamma emitter which is predominately created by the fast neutron interaction with O-16 present in the reactor core water. During reactor operation at different power level, the concentration of N-16 at the reactor bay region may increase causing radiation risk to the reactor operating personnel or the general public. Concerning the safety of the research reactor, the present study deals with the estimation of N-16 activity concentrations in the regions of reactor core, reactor tank, and reactor bay at different reactor power levels under natural convection cooling mode. The estimated N-16 activity concentration values with 500 kW reactor power at the reactor core region was $7.40{\times}10^5Bq/cm^3$ and at the bay region was $3.39{\times}10^5Bq/cm^3$. At 3 MW reactor power with active forced convection cooling mode, the N-16 activity concentration in the decay tank exit water was also determined, and the value was $4.14{\times}10^{-1}Bq/cm^3$.

• KSBB Journal
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• v.8 no.3
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• pp.224-229
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• 1993

The feeding effects of Rosa rugosa roots powder extracted with two different extracting solvents on lipid metabolism in rats were evaluated. Rats were fed with purified diets containing methanol or 70% aqueous acetone extracts at a 1% level for 4 weeks. In addition, to examine the effects of age, rats with different ages (4weeks old vs. 3 months old) were fed with purified diets containing methanol extracts at a 1% level for 4weeks. Feeding of methanol extracts decreased the concentration of triacylglycerol in serum and liver, whereas the aqueous acetone extracts lowered the concentration of liver triacylglycerol with concomitant elevation of the concentration of serum triacylglycerol. The methanol extracts ameliorated the degree of increase in the serum triacylglycerol level in relation to age and decreased especially the concentration of free fatty acid in serum of adult rats. The results suggested possibility that the regulatory mechanism responsible for triacylglycerol-lowering effects of Rosa rugosa roots extracts in the liver could be modulated by differences in the components of extracts due to the variation in extracting solvents, and that the methanol extracts might be effective in lowering an age-dependent increase in the concentration of serum and liver triacylglycerol in rats.