• Journal of Marine Life Science
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• v.7 no.2
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• pp.154-162
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• 2022

In this study, data on the types and density of abalone attached organisms were provided in marine net cage of the southern coast. In addition, the effect of the removal of attached organisms was evaluated. In marine net cage, oysters, bryozoa, and barnacles were dominated among the attached organisms, and their average area ratio was about 57.5%. The growth rate and hepatopancreas condition were better in removal group of attached organisms than control group. Therefore, it is judged that the removal of attached organisms from abalone is necessary for the growth of individuals and improvement of value.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.234-235
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• 2002

해양 규조류는 일차생산자로서의 중요성 이외에도 수질 오염의 정도를 파악하거나 생리학 내지는 내성 연구나 규산 대사에 관한 연구에도 가장 많이 사용되어지고 있는 주요 식물플랑크톤이다 (Werner,1977;Wear, 1999). 이 중 특정 기질에 부착하여 서식하는 규조류를 부착규조라고 하며, 해초와 같은 식물, 저질, 동물의 표면, 이 외의 여러 부착기질에 점액질을 이용하여 부착 서식한다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.785-795
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• 2018

The International Maritime Organization (IMO) has recognized the risk of hull fouling and announced '2011 Guidelines for the control and management of ship's biofouling to minimize the transfer of invasive aquatic species'and is planning international regulations to enforce them in the future. In this study, to effectively respond to future international regulation, we introduce the case of leading countries related to management of hull fouling and also investigate environmental risk assessment techniques for in-water cleaning. Australia and New Zealand, the leading countries in hull fouling management, have established hull fouling regulations through biological and chemical risk assessment based on in-water cleaning scenarios. Most European countries without their government regulation have been found to perform in-water cleaning in accordance with the IMO's hull fouling regulations. In the Republic of Korea, there is no domestic law for hull fouling organisms, and only approximately 17 species of marine ecological disturbance organisms, are designated and managed under the Marine Ecosystem Law. Since in-water cleaning is accompanied by diffusion of alien species and release of chemical substances into aquatic environments, results from biological as well as chemical risk assessment are performed separately, and then evaluation of in-water cleaning permission is judged by combining these two results. Biological risk assessment created 40 codes of in-water cleaning scenarios, and calculated Risk Priority Number (RPN) scores based on key factors that affect intrusion of alien species during in-water cleaning. Chemical risk assessment was performed using the MAMPEC (Marine Antifoulant Model to Predict Environmental Concentrations), to determine PEC and PNEC values based on copper concentration released during in-water cleaning. Finally, if the PEC/PNEC ratio is >1, it means that chemical risk is high. Based on the assumption that the R/V EARDO ship performs in-water cleaning at Busan's Gamcheon Port, biological risk was estimated to be low due to the RPN value was <10,000, but the PEC/PNEC ratio was higher than 1, it was evaluated as impossible for in-water cleaning. Therefore, it will be necessary for the Republic of Korea to develop the in-water cleaning technology by referring to the case of leading countries and to establish domestic law of ship's hull fouling management, suitable for domestic harbors.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.1078-1085
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• 2022

Fouling organisms attached to a ship not only greatly increase the resistance of the ship as they grow on the hull but also cause disturbances in local marine ecosystems as they move with the ship. Accordingly, the International Maritime Organization has started discussing the removal of biofouling and evaluation of cleaning performance to prevent the migration of hull-fouling species. In this study, specimens of FRP(Fiber Reinforced Plastic), HDPE(High Density Polyethylene), and CFRP(Carbon Fiber Reinforced Plastic) materials used for small ship construction were cured in Gyeokpo Port (Jeonlakbuk-do) for about 80 days. Then, attached organism removal experiments were performed using a water jet nozzle. The results show that seaweeds, such as laver, were removed when the distance between the nozzle and the specimen was 1.8 cm and the pressure was 100 bar. Furthermore, it was confirmed that the cleaning of barnacles was possible only when the pressure was 200 bar or more.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.218-224
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• 2008

Coal-, coconut- and wood-based activated carbons and anthracite were tested to evaluate adsorption and biodegradation performances of chloral hydrate. In the early stage of the operation, the adsorption was the main mechanism for the removal of chloral hydrate, however as increasing populations of attached bacteria, the bacteria played a major role in removing chloral hydrate in the activated carbon and anthracite biofilter. It was also investigated that chloral hydrate was readily subjected to biodegrade. The coal- and coconut-based activated carbons were found to be most effective adsorbents in adsorption of chloral hydrate. Highest populations and activity of attached bacteria were shown in the coal-based activated carbon. The populations and activity of attached bacteria decreased in the order: coconut-based activated carbon > wood-based activated carbon > anthracite. The attached bacteria was inhibited in the removal of chloral hydrate at temperatures below 10$^{\circ}C$. It was more active at higher water temperatures(20$^{\circ}C$ <) but less active at lower water temperature(10$^{\circ}C$>). The removal efficiencies of chloral hydrate obtained by using four different adsorbents were directly related to the water temperatures. Water temperature was the most important factor for removal of chloral hydrate in the anthracite biofilter because the removal of chloral hydrate depended mainly on biodegradation. Therefore, the main removal mechanism of chloral hydrate by applying activated carbon was both adsorption and biodegradation by the attached bacteria. The observation suggests that the application of coalbased activated carbon to the water treatment should be the best for the removal of chloral hydrate.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.6
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• pp.318-324
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• 2017

We evaluated geosmin and MIB biodegradation and adsorption mechanism of biological activated carbon (BAC) and anthracite biofilter. In steady state of BAC process, the geosmin and MIB were completely removed at the 30 min empty bed contact time (EBCT) even though low water temperature ($9^{\circ}C$) in which the activity of attached bacteria decreased. When the water temperature was $26^{\circ}C$, the microbial biomass and activity were higher at the upper layer of the biofilm than at $9^{\circ}C$, and the microbial biomass and activity decreased as the depth was deeper. This is because when the water temperature is high, the biodegradable organic matter (BOM) removal rate in the upper layer is high and the BOM amount that can't be supplied to the lower layer. The Removal rate of geosmin and MIB by BAC process did not show a significant difference compare to activity-inhibited BAC by treated with azide and the biofilter also removed the geosmin and MIB by biological action. It means geosmin and MIB could be removed by competitive relationship between adsorption and biodegradation.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.749-755
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• 2013

The purposes of this research are to know the optimal gab and electric pressure (voltage) of electrode-plates coated with activated carbon and also to study their arrangement through dust removal efficiency. From the experimental results of attached dust mass at different electrode-plate gab, the frequency of attachment and detachment of dust was more increased as electrode-plate gab was closer. In attached dust mass per unit area of electrode-plate, the farther electrode gab, the more increased. But in total attached dust mass, the closer electrode gab, the more removed. From the experimental results, the optimal electrode arrangement in dust removal chamber was considered that the forward parts of chamber need to be increased the number of electrode-plate, the backward parts to be increased them. The dust attachment have no relation with electric pressure while showing high removal efficiency under condition of 5 kV of voltage and 2 cm of electrode-plates gab.

• The Journal of the Korean dental association
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• v.37 no.10 s.365
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• pp.766-771
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• 1999

칫솔은 치면에 부착된 프라그 등의 부착물을 물리적으로 제거하기에 가장 합리적이고 간편하게 사용할 수 있도록 설계된 구강청소용구이다. 가장 흔하지만 무심코 지나치기 쉬운 칫솔 칫솔의 역사와 칫솔의 종류, 1300억에 이르는 칫솔시장을 분석해 본다.

• Journal of Environmental Impact Assessment
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• v.19 no.4
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• pp.443-452
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• 2010

본 연구에서는 도시지역의 하나인 주거지역에서 배출되는 강우유출수 내에 중금속이 장치형 비점 오염저감시설 중에 하나인 와류형시설에서 제거되는 특성을 파악하고자, 대상 중금속을 Zn으로 삼고 2007년 4월부터 2008년 11월까지 모니터링을 수행하였다. 유출수 모니터링은 와류형 시설의 유입부와 유출부에서 유량과 수질을 각각 시간변화에 따라 측정하였으며, 시설유입부와 유출부, 그리고 시설하부에 쌓인 침전물을 채취하여 침전물 모니터링도 수행하였다. 그 결과, 높은 강우강도에서 발생된 강우유출수는 와류형 시설내에 HRT를 감소시켜 Zn의 제거효율이 낮게 관측되었으며, 특히 HRT가 20분이내의 조건이 될 경우에는 처리효과가 없는 것으로 확인되었다. Zn는 입자성물질과 밀접한 관계를 맺으며 제거되는 특성을 보였으며, 입자성물질이 스크린에 의한 여과 및 침전작용이 일어날 때 입자성물질에 부착되어 거동하는 특성을 보였다. 그 중에 0.075mm 이하의 미세한 입자에 부착된 고농도의 Zn는 제거되지 못하였고, 와류형 시설 후단에 후처리시설로서 저류시설을 두어 충분한 HRT를 제공한 결과, 와류형 시설만을 운전하였을 때와 비교하여 높은 제거특성을 보이게 되었다.

• Journal of Embryo Transfer
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• v.13 no.1
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• pp.29-36
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• 1998

실험1. 난구-난자 복합체(CIO)와 나화난자(DO)의 성숙배양 개시후 3~24시간 동안 각각의 난자에 행성숙 진행상태를 Hㅐㄷ촌ㅅ 33342로 염색하여 관찰하였다. GV기는 성북배양 개시후 3시간에 GVBD기는 6시간에, MI기는 13시간에, AnaI-Tel I 기는 16시간만에, M II기는 24시간에 각각 관찰되었으며, CIO와 DO에 있어 각각의 핵성숙 진행 비율의 차이는 인정되지 않았다. 실험2. 실험 1에서 결정된 각각의 핵성숙 시간에 CIO로부터 난자세포를 제거하는 것이 난자의 24시간 성숙배양을 제거하여도 M II의 비율과 수정율에는 미치지 않았다. 성숙배양 개시후 0,3,6시간에 난구세포를 제거한 난자의 분할율은 성숙배양 개시후 13,16,24시간에 제거한 난자에 비하여 유의하게 낮았다(p<0.02). 또한 성숙배양 개시후 0,3,6,13시간에 난구세포를 제거한 난자의 배발포배 발생율은 16,24시간에 난구세포를 제거한 난자에 비하여 유의하게 낮았다(p<0.01). 이상의 결과는, 체외 소난자의 핵성숙 진행시기는 부착된 난구세포에 의존하지 않으며, 난자와 난구세포의 결합상태를 성숙배양 개시후 13~16(MI)까지 즉 MI기에 도달 할 때까지 유지시키는 것은 난자의 수정후 배발생에 있어 필수적인 것임을 시사하였다.