간행물

한국환경과학회지 KCI 등재 Journal of Environmental Science International

권호리스트/논문검색
이 간행물 논문 검색

권호

제20권 제8호 (2011년 8월) 13

1.
2011.08 서비스 종료(열람 제한)
A novel conductivity technique was developed to detect penetration depth of the vessel fluid into the feedpipe. For a given reactor geometry, critical agitator speeds were experimentally determined at the onset of feedpipe backmixing using Rushton 6 bladed disk turbine (6BD) and high efficiency axial flow type 3 bladed (HE-3) impellers. The ratio of the feedpipe velocity to the critical agitator speed (vf/vt) was constant for either laminar or turbulent feedpipe flow regimes. Compared to the results of fast competitive reaction, feedpipe backmixing had to penetrate at least one feedpipe diameter into the feedpipe to significantly influence the yield of the side product. However, higher vf/vt than that for L/d = 0 (position at the feedpipe end) of the conductivity technique is recommended to completely eliminate feedpipe backmixing in conservative design criteria. The conductivity technique was successful in all feedpipe flow conditions of laminar, transitional and turbulent flow regimes.
2.
2011.08 서비스 종료(열람 제한)
We investigated the effects of temperature changes on the oxygen consumption rhythm in Japanese eels, Anguilla japonica, using an automatic intermittent flow respirometer (AIFR). The endogenous rhythm of the oxygen consumption rate (OCR) in the eels (n = 18; 44-74 cm, 145-690 g), freshly collected by bag net from estuaries, was nearly synchronous with the tidal pattern of the estuarine collection site. The magnitude of mean OCR (mOCR) of eels showed variable range of 82.2 - 116.5 ml O2 kg-1 ww h-1 under constant conditions. In case of increasing temperature from 25 to 38℃, the OCR of eels exhibited a gradually increasing trend with a rhythmic pattern until 36℃. Above 36℃, the rhythms of the OCR dampened and the OCR decreased rapidly at around 36 - 37℃. The OCR of the eels exhibited the maximum value at 38℃, and then it sharply decreased. The results suggested that the critical thermal maximum (CTM) regarding the endogenous rhythms of the eels was at around 36 - 37℃ when water temperature increased at 0.5℃/14 h following the acclimation at 25℃. In case of decreasing temperature (0.5℃/14 h) from 25 to 0℃, the OCR of the eels displayed a abrupt decrease up to 23℃, and between at 23 and 20℃, there was an agitation which showed a slight increase in the OCR with a duration of 1-2 days. Below 9℃, the OCR rhythm of the eels showed a constant state regardless of temperature decreasing. These results suggest that the Japanese eel has an upper incipient lethal temperature at 36℃, with a lower thermal limit at 9℃. The biochemical aspects of the eels influenced by water temperature need to be further studied.
3.
2011.08 서비스 종료(열람 제한)
The covered stream of cities are considered an odor source. Also, the public do not want a wastewater treatment plant(WWTP) near their properties due to the emission of odor emanating from such sources, although they play an important role in urban development. The purpose of this study is to analyze the pattern distribution of the odorous compounds from the Nambu WWTP and Youngho stream in Busan. odor sampled four times were analyzed by instrumental analysis method and indirect olfactory method. The kinds of offensive odorous compounds examined are acetaldehyde, propion aldehyde, hydrogen sulfide, methyl mercaptan, dimethyl sulfide and ammonia. Also, Concentration of air pollutants has been calculated by ISCST3 models. At the result of this study, The Nambu WWTP releases sulfur compounds. And the major odorous were hydrogen sulfide (1,475 ppb) and acetaldehyde (95 ppb) at Youngho stream. The stink which residents feel will point out the Nambu WWTP mainly if the odor is removed with the improvement of a Youngho stream. Accordingly, we should pay more attention to appropriate components to processes in odor reducing plan at Nambu WWTP.
4.
2011.08 서비스 종료(열람 제한)
For this research, they were monitored CO2 flux and environmental factors (CO2 concentration, soil temperature, soil moisture, soil organic carbon, soil pH, soil Eh) in foreshore, paddy field and woods sites at the winter season (January 2009) and the summer season (September 2009). Seasonal and spatial variations for monitored data were analyzed, and linear regression functions of CO2 flux as environmental factors were estimated. CO2 fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the winter season were shown -8 mgCO2m-2hr-1 and -25 mgCO2m-2hr-1, respectively. CO2 fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the summer season were shown 47 mgCO2m-2hr-1 and 117 mgCO2m-2hr-1, respectively. Thus, CO2 was sunk from atmosphere to surface at the winter season and it was emitted from surface to atmosphere at the summer season. CO2 fluxes in woods site were emitted 145 mgCO2m-2hr-1 at the winter season and 279 mgCO2m-2hr-1 at the summer season.
5.
2011.08 서비스 종료(열람 제한)
This study analyzed the characteristics of stormwater runoff in the orchard areas and quantitatively estimated effluence of nonpoint source pollutants for the volume of runoff. Two target areas under vine cultivation were each 2,000㎡ and 1,800㎡, located in Gyeongju City. Since grape was the only crop on the target area, the characteristics of stormwater runoff at vineyard could be evaluated independently. A total of 51 rainfall events in the vineyard area during two years(2008-2009) was surveyed, and 19 of them became stormwater runoff, with rainfall ranging 16.5 - 79.7 mm and antecedent dry period of 1-13 days. The pollutant runoff loads by volume of stormwater runoff showed BOD ranging 19.5 - 45.3% in 30% of runoff volume. The average pollution discharge rate was 32.4%, indicating small first flush effect of BOD. The range of SS concentrations was 5 –52.0% in 10% of runoff volume, showing the average 28.7% of discharge rate, about 3 times more than rainfall effluent. TOC and TN appeared to be similar to the results of BOD, the average discharge rate of 30.9% and 30.6% for TOC and TN, respectively, for 30% of stormwater runoff volume. Average discharge rate of COD and TP in the same runoff volume was 35.1% and 36%, respectively, showing comparatively high discharge ratio. As the targeted vineyard area was permeable land, the pollution load ratio against rainfall-runoff volume appeared to be 1:1, implying no strong first flush effect for all the survey items.
6.
2011.08 서비스 종료(열람 제한)
Co-planar PCBs(polychlorinated biphenyls) of non-ortho are investigated in soil and ginseng on the North Gyeongbuk with HRGC/HRMS. PCB77 in soil on Yeongju and Sangju are detected 0.0007 pgTEQ/g and 0.0009 pgTEQ/g, respectively. PCB81 in soil on Yeongju and Sangju are detected 0.0113 pgTEQ/g and 0.0108 pgTEQ/g, respectively. Also PCB126 in soil on Yeongju and Sangju are detected 0.0907 pgTEQ/g and 0.0944 pgTEQ/g, respectively. But PCB169 in soil on Yeongju and Sangju is not detected. Total Co-planar PCBs of non-ortho in soil on Yeongju and Sangju are 0.1027 pgTEQ/g and 0.1061 pgTEQ/g, respectively. PCB77 in ginseng on Yeongju and Sangju are detected 0.0008 pgTEQ/g. Then PCB81 in ginseng on Yeongju and Sangju are detected 0.0104 pgTEQ/g and 0.0112 pgTEQ/g, respectively. But PCB126 in ginseng on Yeongju and Sangju are detected 0.0585 pgTEQ/g and 0.0579 pgTEQ/g, respectively. PCB169 in ginseng on Yeongju and Sangju is not detected. Total Co-planar PCBs of non-ortho in ginseng on Yeongju and Sangju are 0.0697 pgTEQ/g and 0.0700 pgTEQ/g, respectively. Relationship of PCBs in between soil and ginseng shown significance(R2 : 0.99).
7.
2011.08 서비스 종료(열람 제한)
In order to estimate volume transport by upwelling for single artificial seamount, same shape and size of artificial seamount already deployed was applied to numerical experiment. The result showed that strong upwelling appeared at front while took place downwelling at rear. The strongest upwelling existed at the top of the artificial seamount. Volume transport by upwelling was computed as 785 m3/s. Column arrangement was applied to two artificial seamount in three cases; case 1) no clearance, case 2) sixty-five meters of clearance as half of artificial seamount’s length, and case 3) hundred-thirty meters of clearance as an artificial seamount’s length. All cases of column arrangements showed more upwelling volume transport than that of single seamount. Particularly, the case of no clearance calculated as 106% and appeared the most upwelling effect comparing to two other cases. Row arrangement was also applied to two artificial seamount in three cases; case 4) no clearance, case 5) forty meters of clearance as an artificial seamount’s width, and case 6) eighty meters of clearance as twice of artificial seamount’s width. Upwelling volume transport in case 4 increased 48% than the case of single seamount. Other two cases of 5 and 6 were estimated as 97% increased and more effective than case 4. According to the case experiments, column arrangements show more upwelling volume transport than that of row arrangements. In cases of column arrangements, with decreasing clearance between two seamount, the effect increases while showing maximum value at clearance zero. In cases of row arrangements, on the contrary, with decreasing clearance between two seamount, the effect decreases while showing minimum value at clearance zero. Since simple barotropic condition was considered for this study, further study is necessary by considering baroclinic condition to get close to reality. In conclusion, in deploying artificial seamount, optimal arrangement should be well designed to enhance primary and secondary productivity and to increase the diversity of species as well as reducing time and space.
8.
2011.08 서비스 종료(열람 제한)
The objective of this research is to evaluate optimal conditions of permeability and selectivity on the polysulfone membrane for efficiency of separation of CH4 by checking four factors which are temperature, pressure, gas compositions and gas flow rates. When higher pressure was applied at the input, lower efficiency of recovery of CH4 and higher efficiency of separation of CH4 were shown. It has the tendency to show lower efficiency of recovery of CH4 and higher efficiency of separation of CH4 at the output as higher temperature at input. The lower flow rates make higher efficiency of recovery of CH4 and lower efficiency of separation of CH4. Finally, over 90% efficiency for CH4 separation and recovery conditions are temperature (-5℃), pressure (8 bar), gas composition rate (6:4) (CH4:CO2) and gas flow rate (5 ℓ/min). These conditions make higher separation and recovery efficiency such as 90.1% and 92.1%, respectively.
9.
2011.08 서비스 종료(열람 제한)
The objective of this study was to assess improvements caused by chitosan, sericin and collagen peptide extract complexes (1:1:1, w/w/w, CSC-F-005) in lipid concentrations in the sera of dyslipidemic rats (SD strain) fed on experimental diets for 5 weeks. Serum concentrations of total cholesterol, HDL-cholesterol, ratio of HDL-cholesterol concentration to total cholesterol, atherosclerotic index, LDL-cholesterol, free cholesterol, cholesteryl ester, triglyceride, phospholipid and blood glucose were effective on the metabolic regulation of dyslipidemic rats. The activities of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase in serum were remarkably lower in the extract complexes (CSC-F-005) than in the dyslipidemic model. From the above results shows that CSC-F-005 extract complexes were effective on the improvement of the lipid metabolism in sera of dyslipidemic rats.
10.
2011.08 서비스 종료(열람 제한)
This study was conducted to examine the influences of chitosan, sericin and collagen extract complexes (1:1:1, w/w/w, CSC-F-005) in blood glucose and lipid concentrations in the sera of streptozotocin (STZ, 55 mg/kg BW, IP injection)-induced diabetic rats (SD strain) fed on experimental diets for 5 weeks. The concentrations of blood glucose, total cholesterol, HDL-cholesterol, ratio of HDL-cholesterol concentration to total cholesterol, atherosclerotic index, LDL-cholesterol, free cholesterol, cholesteryl ester, triglyceride (TG) and phospholipid (PL) in serum were effective on the metabolic regulation in diabetic rats. The activities of alkaline phosphatase (ALP) and aminotransferase (AST, ALT) in serum were lower in the extract complexes (CSC-F-005) than in the diabetic rats. The results shown above suggested that CSC-F-005 extract complexes supplementation effectively improvement of blood glucose and lipid components in the serum of STZ-induced diabetic rats.
11.
2011.08 서비스 종료(열람 제한)
The purpose of this study was to analyze the effects on meteorological variables in Seoul, Busan and Jeju during the partial solar eclipse event of 22 July 2009 in Korea. Solar irradiance decreased 16 and 19 minutes after eclipse in Seoul and Busan, and 6 minutes before eclipse in Jeju. Minimum solar irradiance occurred 7 and 3 minutes after maximum eclipse in Seoul and Busan, respectively, and 8 minutes before maximum eclipse in Jeju. Solar irradiance began to increase after maximum eclipse in Seoul and Busan, and recovered to the original state as eclipse ended. On the other hand, recovery of solar irradiance after maximum eclipse in Jeju was slower than those of two cities. Temperature drop due to partial solar eclipse were 0.7℃, 4.0℃, 1.5℃ in Seoul, Busan, and Jeju, respectively, and time needed to arrive minimum temperature from maximum eclipse were each 12, 32, 30 minutes, respectively. Change of relative humidity during partial solar eclipse were 2.6%, 17.4%, 12.3% in Seoul, Busan, and Jeju, respectively. Temperature drop turned out to be sharper as altitude increases. Wind speed decreased by each about 1.1 ㎧, 3.4 ㎧, 1.4 ㎧ due to partial solar eclipse in Seoul, Busan, and Jeju. Soil temperature of 5 ㎝ equally decreased by 0.2℃ in Seoul and Busan, soil temperature of 10 cm maintained almost constant, and soil temperature of 20 cm was hardly affected by eclipse.
12.
2011.08 서비스 종료(열람 제한)
This paper examines the effects of the partial solar eclipse of 22 July 2009 across the Korean peninsular on surface temperature and ozone concentrations in over the Busan metropolitan region (BMR). The observed data in the BMR demonstrated that the solar eclipse phenomenon clearly affects the surface ozone concentration as well as the air temperature. The decrease in temperature ranging from 1.2 to 5.4℃ was observed at 11 meteorological sites during the eclipse as a consequence of the solar radiation decrease. A large temperature drop exceeding 4℃ was observed at most area (8 sites) of the BMR. Significant ozone drop (18∼29 ppb) was also observed during the eclipse mainly due to the decreased efficiency of the photochemical ozone formation. The ozone concentration started to decrease at approximately 1 to 2 hours after the event and reached its minimum value for a half hour to 2 hours after maximum eclipse. The rate of ozone fall ranged between 0.18 and 0.49 ppb/min. The comparison between ozone measurements and the expected values derived from the fitted curve analysis showed that the maximum drop in ozone concentrations occurred at noon or 1 PM and was pronounced at industrial areas.
13.
2011.08 서비스 종료(열람 제한)
Evapotranspiration is one of the important elements related water cycle and there is many kind of measurement method of evapotranspiration today. This study developed mini lysimeter for the purpose of direct measurement of evapotranspiration and installed on 5th, July, 2010 at the field of MRI which located at Tsukuba, Ibaraki, Japan for continuous measurement and understand relation between evapotranspiration and meteorological elements expecially radiation elements. And compared the evapotranspiration data of lysimeter with Bowen Ratio Method. The result of this study is as follows; There is high related with solar radiation and evapotranspiration with R2=0.947. and 46 % of solar radiation converted into evapotranspiration during clear 5 days. In net radiation also highly related with evapotranspiration, we can derive evapotranspiration is mainly controlled by radiation energy in clear days. From the 104 days data, there is only 9 % difference between Bowen Ratio Method and evapotranspiration of lysimeter which was developed from this study is very useful to estimate evapotranspiration at field site with simple and high accuracy. High accuracy and resolution measurement of evapotranspiration by lysimeter can give a chance further study of meteorological phenomena of on ground expecially in night time condensation which means abnormal energy flow.