본 연구는 마지에서 마유 추출시 천연 항산화제인 건조 녹차잎을 다양한 농도로 첨가하여 추출공정 및 저장기간동안 지방산패 특성을 관찰하고자 하였다. 마유의 품질특성을 식품공전에 고시되어 있지 않지만 산가, 과산화물과, TBA가, 요오드화가 등의 품질특성관찰을 통해 다른 종류의 식용유지의 규격과 비교하여 보았다. 또한 천연 항산화 제인 녹차잎 첨가로 인해 추출 및 저장시 지방산패를 어느 정도 방지할 수 있는지 확인 가능하였다. 지방산조성 분석 을 통해 마유의 포화지방산 및 불포화지방산 조성 변화도 관찰하였다. 따라서 본 연구를 통하여 최근 이용도가 높아 지는 마유의 기준 규격마련을 위한 기초자료로 사용 가능할 것으로 판단된다.

인천연안은 인천광역시, 경기도 김포시·시흥시·안산시 일대로, 양식장에서 발생하는 쓰레기, 어업활동 후 버려진 어구·어망, 육상에서부터 한강을 타고 흘러오는 쓰레기 때문에 인천연안의 해양생태계의 변화가 우려되고 있다. 인천연안이 심각하게 오염되자 해양수 산부는 인천연안을 특별관리해역으로 지정하여 해양환경 자산인 해역수질을 보존하고 있다. 이러한 배경 하에서 본 연구는 인천연안 해역수질의 비시장 가치를 선택실험법(choice experiment)을 이용하여 평가한다. 이를 위해, 전국 1,000 가구를 대상으로 면대면 설문조사를 실시하였고, 속성 각각의 한계지불의사액(MWTP, marginal willingness to pay)을 추정한다. 인천연안 해역수질의 속성별 가치(가구당 연간 한 계지불의사액)를 추정한 결과, 가구당 연간 해역수질 1%p 개선의 MWTP는 75원, 동물종의 다양성 증가의 MWTP는 135원, 식물종 다양성 증가의 MWTP는 309원, 해양쓰레기 1%p 저감의 MWTP는 72원으로 나타났다. 모든 추정결과는 유의수준 1 %에서 유의한 것으로 나타났다. 본 논문의 주요 결과는 정책당국에 해양환경 관리정책 수립과 평가에 유용하게 활용될 수 있다.

Applicability of corrosion inhibitor was evaluated using pilot scale water distribution pipe simulator. Calcium hydroxide was used as corrosion inhibitor and the corrosion indices of the water were investigated. Corrosion indices, Langelier saturation index (LI) increased by 0.8 and calcium carbonate precipitation potential (CCPP) increased by 9.8 mg/L. This indicated that corrosivity of water decreased by corrosion inhibitor and the effects lasted for 18 days. Optimum calcium hydroxide dose was found to be 3~5 mg/L for corrosion inhibition. We suggest that monitoring of CCPP as well as LI need to be conducted to control corrosivity of water.

In this study, the effects of operating conditions on the formation of reversible and irreversible fouling were investigated in the filtration using ceramic membrane for water treatment process. The effect of coagulation pretreatment on fouling formation was also evaluated by comparing the performance of membrane filtration both with and without addition of coagulant. A resistance-in-series-model was applied for the analysis of membrane fouling. Total resistance (RT) and internal fouling resistance (Rf) increased in the membrane filtration process without coagulation as membrane flux and feed water concentrations increased. Internal fouling resistance, which was not recovered by physical cleaning, was more than 70% of the total resistance at the range of the membrane flux more than 5 m3/m2･day. In the combined process with coagulation, the cake layer resistance (Rc) increased to about 30-80% of total resistance. As the cake layer formed by coagulation floc was easily removed by physical cleaning, the recovery rate by physical cleaning was 54~90%. It was confirmed from the results that the combined process was more efficient to recover the filtration performance by physical cleaning due to higher formation ratio of reversible fouling, resulted in the mitigation of the frequency of chemical cleaning.

본 연구는 넙치 양식장 시설 내로 유입되는 병원 미생물을 효과적으로 관리하기 위한 오존 처리 기준을 마련하고자 수행되었다. 유수식 환경에서 오존 주입량을 0.3∼3.0 mg O3 L-1의 범위로 주입하면서 3분의 반응시간을 가진 후 ORP 320~410 mV에서 TRO가 0.01±0.01 mg L-1가 검출되었으며, 600 mV와 700 mV에서 0.07±0.02 mg L-1와 0.16±0.03 mg L-1가 검출되었다. 오존 처리에 따라 총세균수는 80.6~97.9%의 제거율을 나타내어 오존 처리를 통한 미생물 제거효과는 분명하게 나타났다. 230 g 넙치를 8.0 kg m-2 밀도로 사육한 300~400 mV 실험구에서는 총세균수는 가장 낮은 값을 보였다. 특히 400~500 mV에서 Vibrio spp.와 그램음성균은 거의 검출되지 않았다. 일간사료섭취율은 300~500 mV에서 0.7% 이상을 나타내어 대조구인 자연해수보다 감소하지 않아 부작용이 적은 것으로 나타났다. 넙치 양식장으로 유입되는 병원 미생물은 유입수의 ORP 400 mV 수준에서 효율적으로 제거되는 것으로 조사되었다.

Rivers continuously transport terrestrial organic carbon matter to the estuary and the ocean, and they play a critical role in productivity and biodiversity in the marine ecosystem as well as the global carbon cycle. The amount of terrestrial organic carbon transporting from the rivers to ocean is an essential piece of information, not only for the marine ecosystem management but also the carbon budget within catchment. However, this phenomenon is still not well understood. Most large rivers in Korea have a well-established national monitoring system of the river flow and the TOC (Total Organic Carbon) concentration from the mountain to the river mouth, which are fundamental for estimating the amount of the TOC flux. We estimated the flux of the total terrestrial organic carbon of five large rivers which flow out to the Yellow Sea, using the data of the national monitoring system (the monthly mean TOC concentration and the monthly runoff of river flow). We quantified the annual TOC flux of the five rivers, showing their results in the following order: the Han River (18.0×109 gC yr-1)>>Geum River (5.9×109 gC yr-1)>Yeongsan River (2.6×109 gC yr-1)>Sumjin River (2.0×109 gC yr-1)>>Tamjin River (0.2×109 gC yr-1). The amount of the Han River, which is the highest in the Korean rivers, corresponds to be 4% of the annual total TOC flux of in the Yellow River, and moreover, to be 0.6% of Yangtze River.

The aims of this study were to analyze the physico-chemical factors and the characteristics of epilithic diatom community from 15 sites of the Naeseongcheon and tributaries located in the upper region of the Nakdong river from May to October 2016. The biological water quality was assessed using DAIpo and TDI. A total of 163 diatom taxa were identified with 2 orders, 3 suborders, 9 families, 35 genera, 145 species, 16 varieties and 2 forms. Cocconeis placentula var. lineata appeared at every examined sites. Achnanthes lanceolata, Nitzschia fonticola, Nitzschia inconspicua and Reimeria sinuata were common taxa of the Naeseongcheon. Nitzschia inconspicua and Achnanthes minutissima were major dominant species. As a result of the CCA, Electrical conductivity and total nitrogen concentration were important factors determining the diatom species composition. In the result of the biological assessment using DAIpo, the Naeseongcheon was rated at class B with an average of 62.38. In the result of assessment using TDI, the Naeseongcheon was rated at class C with an average of 66.12.

본 연구는 국내 배추 주산단지 5지역을 대상으로 배추 재배에 활용되는 농업용수를 각 지역의 수확 시기에 채취 하여 위생지표세균(총대장균군, 대장균, 장구균)과 이화학 성분을 분석함으로써 농업용수의 수질의 오염도를 조사하기 위하여 수행되었다. 그 결과 지하수 보다 지표수에서 위생지표세균이 높은 수준으로 검출되었다. 지표수의 경 우 총대장균군 1.96-4.96 log MPN/100 mL, 지하수의 경우 0-3.98 log MPN/100 mL 수준이었다. 장구균의 경우 지표 수에서 95% (72/75), 지하수에서 22% (8/36) 빈도로 검출 되었으며, 대장균의 경우 지표수에서 100% (72/75), 지하수에서 22% (8/36) 빈도로 검출되었다. 위생지표세균과 이 화학성분의 상관관계를 조사한 결과, 지표수의 경우 대장균군과 대장균은 총인과 상관성을 보였으며, 장구균은 부유물질과 생물학적산소요구량에 상관성을 보였다. 지하수의 경우 위생지표세균은 부유물질과 화학적산소요구량에 상관성을 보였다. 본 연구의 결과는 엽채류 재배에 사용되는 농업용수의 미생물 기준을 설정하기 위한 기초자료 로 활용될 수 있을 것으로 판단된다.

본 연구는 생태계 모델을 이용하여 부산연안으로 유입되는 부하량 삭감에 따른 해역의 수질개선 정도를 예측하였다. 모델링 결과에 의하면 COD, T-N, T-P 모두 수영만 연안과 낙동강 하구에서 뚜렷한 개선을 나타냈으며, 수영만을 제외한 만 중부에서 만 동쪽까지 는 수질개선이 거의 나타나지 않았다. 이는, 부산연안이 남해에 위치한 다른 해역에 비해 개방형경계를 가지고 있어서, 물질교환이 빠르 기 때문으로 판단된다. 수질개선을 위한 본 해역의 삭감 COD 부하량은 타 해역에 비해 적었고, 총 유입부하량에 대한 삭감비율 또한 작게 나타났다. 본 연구에 적용한 부하삭감량을 적용하면 수영만, 낙동강 하구부근에서 뚜렷한 수질개선효과를 얻을 수 있을 것으로 판단된다.

Pulp and paper industry produces large volumes of wastewater and residual sludge waste, resulting in many issues in relation to wastewater treatment and sludge disposal. Contaminants in pulp and paper wastewater include effluent solids, sediments, chemical oxygen demand (COD), and biological oxygen demand (BOD), which should be treated by wastewater treatment processes such as coagulation and biological treatment. However, few works have been attempted to predict the treatment efficiency of pulp and paper wastewater. Accordingly, this study presented empirical models based on experimental data in laboratory-scale coagulation tests and compared them with statistical models such as artificial neural network (ANN). Results showed that the water quality parameters such as turbidity, suspended solids, COD, and UVA can be predicted using either linear or expoential regression models. Nevertheless, the accuracies for turbidity and UVA predictions were relatively lower than those for SS and COD. On the other hand, ANN showed higher accuracies than the emprical models for all water parameters. However, it seems that two kinds of models should be used together to provide more accurate information on the treatment efficiency of pulp and paper wastewater.

Abstract1It takes lots of time and labor if a worker have to measure the water quality at a certain but designated time every day in an un-automated aqua farm. In addition, if the equipment is soaked in the sea water consistently, it will be contaminated by diverse floating matters and barnacles, and it often becomes mal-functional within 2~3 months. Therefore, we need to develop a system with which the sensed data could be checked in real time and operated automatically, while preventing the contamination of the sensor, a crucial component for water quality measuring equipment, as much as possible, and increasing the replacement cycle. We have developed a non-cleaning water quality measuring equipment and its software which are used in the fishery household of offshore aqua farms. By providing the workers with a mobile application which has a function of monitoring the water quality in real time, they can check the situation directly without going to the fishery household.

The sewage and wastewater (SAW) are a well-known major source of eutrophication and greentide in freshwaters and also a potential source of thermal pollution; however, there were few approaches to thermal effluent of SAW in Korea. This study was performed to understand the behavioral dynamics of the thermal effluents and their effects on the water quality of the connected streams during winter season, considering domestic sewage, industrial wastewater and hot spring wastewater from December 2015 to February 2016. Sampling stations were selected the upstream, the outlet of SAW, and the downstream in each connected stream, and the water temperature change was monitored toward the downstream from the discharging point of SAW. The temperature effect and its range of SAW on the stream were dependent not only on the effluent temperature and quantity but also on the local air temperature, water temperature and stream discharge. The SAW effects on the stream water temperature were observed with temperature increase by 2.1~5.8℃ in the range of 1.0 to 5.5 km downstream. Temperature effect was the greatest in the hot spring wastewater despite of small amount of effluent. The SAW was not only related to temperature but also to the increase of organic matter and nutrients in the connected stream. The industrial wastewater effluent was discharged with high concentration of nitrogen, while the hot spring wastewater was high in both phosphorus and nitrogen. The difference between these cases was due to with and without chemical T-P treatment in the industrial and the hot spring wastewater, respectively. The chlorophyll-a content of the attached algae was high at the outlet of SAW and the downstream reach, mostly in eutrophic level. These ecological results were presumably due to the high water temperature and phosphorus concentration in the stream brought by the thermal effluents of SAW. These results suggest that high temperature of the SAW needs to be emphasized when evaluating its effects on the stream water quality (water temperature, fertility) through a systematized spatial and temporal investigation.

Electrolyzed water(EW) was used for washing of mungbean sprouts to reduce microorganism counts. The aerobic bacteria and yeasts and mold counts in commercial mungbean sprouts were 7.67 and 7.70 log CFU/g, respectively, indicating that the contamination level of the sprouts was very high. Mungbean sprouts were washed EW produced at varying flow rates of brine and water streams. EW produced with 100 ml/min of brine and 300 ml/min of water showed the best performance in reducing microorganisms without affecting the sensory quality of mungbean sprouts. The EW washing showed no signification negative effects on reducing sugar, total phenolics and DPPH radical scavenging activity of mungbean sprout. For further storage of mungbean sprouts. EW washing was effective for reducing microbial counts during storage.

This study evaluated the quality characteristics of semi-dried noodles prepared with different water contents (wet noodles; 32, 24, 22, 20%, dry noodles; 12%). The drying process was carried out in a drying chamber at 13~18oC temperature and 75~95% humidity. The proximate composition of Korean wheat flour was as follows: water 22.1±3.64%, protein 8.6±0.13%, fat 1.3±0.10%, ash 0.7±0.02%, carbohydrates 67.3±0.10%. As water contents decreased, both L and b values significantly decreased before cooking of noodles, whereas L, a, and b values were not significantly different after cooking of noodles. Weight, water absorption, and volume of cooked noodles significantly increased as water content decreased, whereas turbidity of soup was not significantly different. Cutting hardness before cooking of noodles significantly increased as water content decreased. Sections of noodles after cooking by SEM (scanning electron microscopy) showed roughness and fewer round starch particles as water content decreased. For overall preferences according to the sensory evaluation, noodles prepared with different water contents were not significantly different. According to the results, semidried noodles have development potential to complement the disadvantages of both wet noodles and dry noodles.

This study was conducted to provide basic data for establishing water pollution prevention for effluent water from soil and stone quarries and downstream river water by investigating waste water and sewage water processing, as well as the state of legislation related to grit chamber installation and water quality analysis. The pH and DO, BOD, T-P, Total coilform of effluent water and stream water showed higher than Ⅲ class but COD and SS, T-N showed less than Ⅲ class. In addition, concentration of BOD and COD, Turbidity were increased following deepened rainfall intensity. And therefore we devise systematic reduction facility and remedy for prevention of water pollution.