• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2489-2497
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• 2023

Co and Eu impurities in the SSCs are nuclides that dominantly influence the neutron-induced radioactive inventory in metal and concrete radwastes (radioactive wastes) during NPP decommission. The impurity concentrations provided by NUREG/CR-3474 were used for the practical range of Co and Eu impurity concentrations to be applied to the code calculations. Metal structures near the core were evaluated to be ILW (intermediate-level waste) for the whole range of Co impurity concentration, so the boundary line between ILW and LLW (low-level waste) has no change for the whole concentration range provided by NUREG/CR-3474. Also, the boundary line between VLLW (very low-level waste) and CW (clearance waste) in the concrete shield could alter a little depending on the Eu impurity concentration within the range provided by NUREG/CR-3474. From this work, it is found that the concentration of material impurities of SSCs gives no critical impact on determining radwaste levels.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.2
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• pp.93-98
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• 1993

To determine the effects of potassium($K_2O$) fertilization level(0, 100, 200 and 300 kg/ha/year) on the growth, dry matter(DM) yield, nutritive value and nitrate nitrogen($NO_3$-N) concentration of grasses grown under shading condition, this experiment was carried out in Grassland Div., LES, 1989. The plants were sampled on different growing seasons (spring, summer and autumn) and growth stages (grazing and soiling), respectively. Shade was controlled artificially ca. 45-50%, and the level of nitrogen fertilization was 200 kg/ha/year in all treatments. Higher DM was produced in spring 1, 453 kg at grazing and 2, 364 kg/ha at soiling stage, and DM production was increased with increasing level of $K_2O$. In this experiment, the optimum amount of $K_2O$ fertilizer was 200 kg/ha. The neutral detergent fiber, acid detergent fiber, DM digestibility, and relative feed value of grasses were not affected by $K_2O$ fertilization, regardless of growing season and growth stage. The $NO_3$-N concentration of grasses grown in spring was very low (ca. 1.0%), regardless of growth stage and $K_2O$ level. However, $NO_3$-N concentration was very high in summer and autumn season, also $NO_3$-N was decreased significantly with increasing level of $K_2O$ fertilization (P<0.05). Application of $K_2O$ fertilizer, therefore, is thoughs to be desirable for reducing $NO_3$-N concentration of grasses, especially in summer and autumn season. So annual split fertilization of $K_2O$ could be recommended on woodland pasture.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.25-35
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• 2015

As livestock manure treatment is becoming a problem, manure application in forest plantation is recommended as an alternative. In this study, to investigate the impact due to liquid manure application in forest plantation, soil, soil water and shallow groundwater quality had been monitored in poplar experimental site where the liquid manure (LM) was applied. Water samples were collected weekly during growing season (April to October) from 2008 to 2011. From the monitoring results, phosphorus concentration in the soil and soil water had no significant difference between LM and control plots. $NO_3$-N concentration of soil water in LM, however, showed higher concentration (13.6 mg/l at 40 cm, 35.1 mg/l at 80 cm) than control plot (1.5 mg/l at 40 cm, 0.5 mg/l at 80 cm). In case of shallow groundwater quality, pH, heavy metal, etc. were satisfied to the national agricultural water quality standard of groundwater and there were no significant difference between upstream and downstream. The $NO_3$-N concentration of shallow groundwater was also not exceeded the national drinking water standard. However, $NO_3$-N concentration in soil water and downstream of shallow groundwater had increased in 2011 when non-composted LM was applied mostly in non-growing season of tree (September). From the results, it is important to control nitrogen source, application time and decomposed or not when LM is applied. In addition, to investigate nitrate source, further long-term monitoring and modelling could be necessary.

• Journal of Environmental Science International
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• v.32 no.7
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• pp.503-520
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• 2023

In this study, numerical simulations using community multiscale air quality (CMAQ) were conducted to analyze the change in ozone (O₃) concentration due to the reduction in nitrogen oxides (NO_x)andvolatile organic compounds (VOCs) emissions in Busan. When the NO_x and, VOCs emissions were reduced by 40% and, 31%, respectively, the average O₃ concentration increased by 4.24 ppb, with the highest O₃ change observed in the central region (4.59 ppb). This was attributed to the decrease in O₃ titration by nitric oxide (NO) due to the reduction of NO_x emissions in Busan, which is classified as a VOCs-limited area. The distribution of O₃ concentration changes was closely related to NO_x emissions per area, and inland emissions were highly correlated with daily maximum concentrations and 8-h average O₃ concentrations. Contrastingly, the effect of emission reduction depended on the wind direction. This suggests that the emission reduction effects may vary depending on the environmental conditions. Further research is needed to comprehensively analyze the emission reduction effects in Busan.

• Journal of Environmental Health Sciences
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• v.30 no.5 s.81
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• pp.417-426
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• 2004

We investigate changing characteristics and concentration distribution of ambient air quality using data from which obtained local ambient air monitoring network and local meterological measuring sites in Gwangju area from January to December in 2003. Sulfur dioxide ($SO_2$) showed that increase from 8 AM and decrease in 6 PM but, it was not drastically changed concentration. it also 0.010 ppm in 1995 from at this time it's decrease step by step and than some constant in year 2001 to 2003. Nitrogen dioxide ($NO_2$) concentration was showed highest peak in 10 AM and increase again at 6 PM. And also it showed peak concentration (0.026 ppm) in 2001 and decreased from after that times. Ozone was showed peak concentration in 1 PM and Nitrogen dioxide was ditto in 10 AM from this data, we can conclude that this two article ws showed chemical reaction by 3 to 5 hours. There was no case of Ozone alarm in Gwangju area since 1995, but it showed highest ozone concentration (over 0.070 ppm) in May and June of the year and 2 to 4 PM of the day and sometimes it showed increase at the dawn. Ozone product optimum condition was that air temperature is over $25^{\circ}C$, no rain and increase solar radiation (over $20MJ/m^2$) and no wind or below 2.0 m/s wind speed.

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.78-88
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• 2003

This study was conducted to investigate the relation between ozone concentration and the affecting factors in Seosan City of Korea from Jan. 2002 to Dec. 2002. We analyzed the air pollutants such as NO$_2$, PM$_{10} $,SO$_2$, CO and the meteorological factors including solar radiation, air temperature, wind speed and relative humidity. The analytical data were taken statistics by SPSS method. The results were as follows: The seasonal average concentration of ozone were detected 35.0 ppb in Spring, 25.4 ppb in Summer, 23.5 ppb in Autumn and 21.4 ppb in Winter. So the difference of concentrations showed significantly in statistics. The hourly ozone concentration in a day was increased at 7-9 AM, peaked at 3-4 PM. The correlation coefficients was negative to ozone concentration and NO$_2$, SO$_2$, CO, relative humidity, but positive to solar radiation, air temperature, wind speed. With stepwise multiple regression analysis on the 8 factors such as NO$ _2$, PMSO$_{10}$,SO$_2$, CO, solar radiation, air temperature, wind speed and relative humidity, the seasonal primary factors were air temperature in spring, relative humidity in summer and solar radiation in autumn and winter. The above results suggest that ozone is the secondary pollutant by photochemical reaction as the concentration of ozone was increased with the raise of solar radiation.

• The Journal of Korean Obstetrics and Gynecology
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• v.27 no.2
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• pp.1-11
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• 2014

Objectives: The purpose of this study was to investigate the effects of Longanae Arillus water extract (LA) on the production of inflammatory mediators in RAW 264.7 cell. LA is used for forgetfulness, insomnia, palpitation symptoms in korean medicine. Methods: In order to evaluate cytotoxicity of LA, cell viability was measured. To investigate anti-inflammatory effects of LA in the lipopolysacharide (LPS)-induced RAW 264.7 cell, the concentration of nitric oxide (NO) and cytokines were measured. And when p-value is below 0.05, it is judged to have the significant difference statistically. Results: 1. LA showed no cytotoxicity. 2. LA inhibited significantly the production on NO at the concentration of 50 and $200{\mu}g/ml$. 3. LA inhibited significantly the production on interleukin (IL)-$1{\beta}$ at the concentration of 25, 50, 100 and $200{\mu}g/ml$. 4. LA inhibited significantly the production on tumor necrosis factor (TNF)-${\alpha}$ at the concentration of 50, 100 and $200{\mu}g/ml$. 5. LA inhibited significantly the production on lipopolysaccharide-induced chemokine (LIX) at the concentration of 25, 100 and $200{\mu}g/ml$. 6. LA inhibited significantly the production on regulated on activation normal T cell expressed and secreted (RANTES) at the concentration of $200{\mu}g/ml$. Conclusions: These results suggest that LA has anti-inflammatory effect.

• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.67-75
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• 1994

Formaldehyde has been in widespread industrial use since World War II . Numerous sources of formaldehyde are present in the indoor environment. Additionally, the current trend toward tighter, more energy efficient buildings with lower ventilation rates has led to increase concentrations of this and other pollutants generated indoors. In this paper, the field survey was carried out once a month from January to MarctL 1994 to measure indoor and outdoor formaldehyde concentration in several underground locations in Seoul. The results could be summarized as follows : 1. At Yang- jae underground shopping center, the mean formaldehyde concentration was 77.8ppb for indoor and 68.4ppb for outdoor. At Ban- po underground shopping center, it was 175.8ppb for indoor and 127.3ppb for outdoor. At Jam- shil underground shop ping center, it was 135.2ppd for indoor and 34.6ppb for outdoor. Indoor the No.2 sub way line, it was 105.6ppb. The formaldehyde concentration using Berge equation was as follows : At Yang- jae underground shopping center, the mean formaldehyde concentration was 85.99ppb for indoor and 72.75ppb for outdoor At Ban- po underground shopping center, it was 254. 17ppb for indoor and 138.14ppb for outdoor. At Jam- shil underground shopping center, it was 249.13ppb for indoor and 36.87ppb for outdoor. Indoor the No.2 subway line, it was 131.73ppb. 3, The result of correlation analysis indicated that the relationship between temperature and formaldehyde concentration is very high( $\gamma $= 0.831 ∼ 0.974). 4. Also, the relationship between humidity and formaldehyde concentration is variant ($\gamma $ = 0.246 ∼0.999). 5. The mean formaldehyde concentration indoor and outdoor Ban- po underground shop ping center and indoor Jam- shil underground shopping center and indoor the No.2 sub way line exceed the American Society of Heating, Refrigeration, Air- conditioning Engineers( ASHRAE) stflndard of 100ppb(120 $\mu $g/m$^{3}$).

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.5
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• pp.37-45
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• 2010

Manure recycling as fertilizer is one of solutions for the environmental problem related with livestock manure treatment as well as the ocean dumping ban act prohibiting manure disposal to the ocean. For the manure disposal, forest area can be a candidate place because the area has a wide range of applicable sites. However, the manure application to the forest has a possibility of causing environmental impacts including water quality problems due to nutrient loading. Therefore it is necessary to investigate water quality impact from manure disposal to the forestry plantation. In this study, ground and soil water quality had been monitored in the bio-circulation experimental forest where low concentration liquid manure (LCLM) was applied. Soil and groundwater samples were collected and analyzed weekly from April to October in 2008 and 2009. The mean and variation of NO3-N concentration in soil water of LCLM treatment places showed higher concentration than the reference places declining during growing season. In the case of groundwater from monitoring well in the downstream of disposal site, the $NO_3$-N concentration was 3.59 mg/L in 2008 and 3.26 mg/L in 2009 in average showing higher concentration than the reference well although the concentration was not exceed the national drinking water standard. To investigate the source of nitrate, $\delta^{15}N$ isotope analysis was also implemented. Its result showed that the LCLM application could be the nitrate source requiring further long-term monitoring soil and water quality.

• Journal of Electrochemical Science and Technology
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• v.8 no.3
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• pp.197-205
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• 2017

Lead dioxide thin films were electrodeposited on nickel substrate from acidic lead nitrate solution. Current efficiency and thickness measurements, cyclic voltammetry, AFM, SEM, and X-ray diffraction experiments were conducted on $PbO_2$ surface to elucidate the effect of lead nitrate concentration, current density, temperature on the morphology, chemical behavior, and crystal structure. Experimental results showed that deposition efficiency was affected by the current density and solution concentration. The film thickness was independent of current density when deposition from high $Pb(NO_3)_2$ concentration, while it decreased for low concentration and high current density deposition. On the other hand, deposition temperature had negative effect on current efficiency more for lower current density deposition. Cyclic voltammetric study revealed that comparatively more ${\beta}-PbO_2$ produced compact deposits when deposition was carried out from high $Pb(NO_3)_2$ concentration. Such compact films gave lower charge discharge current density during cycling. SEM and AFM studies showed that deposition of regular-size sharp-edge grains occurred for all deposition conditions. The grain size for high temperature and low concentration $Pb(NO_3)_2$ deposition was bigger than from low temperature and high concentration deposition conditions. While cycling converted all grains into loosely adhered flappy deposit with numerous pores. X-ray diffraction measurement indicates that high concentration, high temperature, and high current density favored ${\beta}-PbO_2$ deposition while ${\alpha}-PbO_2$ converted to ${\beta}-PbO_2$ together with some unconverted $PbSO_4$ during cycling in $H_2SO_4$.