• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.339-347
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• 2000

An algicidal bacterium, Micrococcus sp. LG-5 against the harmful dinoflagellate, Cochlodinium polykrikoides was isolated. The optimal conditions for the highest algicidal activity of bacterial culture filtrate showed in the range of $20{\~}30^{\circ}C$, at pH 7.0 and $3.0{\%}$ of NaCl concentration. In addition, $IC_(50)(mean of 50{\%} inhibitory concentration)$ of the culture filtrate against C. polykrikoides after incubation of 5 days was $0.482{\%}$. To investigate heat and pH stability of the culture filtrate of Micrococcus sp. LG-5, the culture filtrate ($pore size, 0.1 {\mu}m$) was heated to $121^{\circ}C for 15 min$ and adjusted pH from 2.0 to 10.0. There were no significant changes in algicidal activity by heat treatment and the pH change between pH from 5.0 to 10.0. The algicidal substances produced from Micrococcus sp. LG-5 were mainly detected in the fraction of $10,000{\~}1,000$ MWCO (molecular weight cut-off). The culture filtrate of Micrococous sp. LG-5 showed antimicrobial activity against Enterococcus faecalis, Escheiichia coli, Uebsiella pneunioniae and Vibrio altinolyticus, but did not show against Pseudomonas aeminosa, P. Buorescens, Salmonella typhi, Staphylococcus aureus, V. cholerae and V parahaemolyicus. The culture filtrate of Micrococcus sp. LG-5 was examined against 16 phytoplankton species and showed the algicidal activity against Ajexandzium tuarense, Eutreptiella Drnnastin, Gymnodinium catenatum, G. mikimotoi, G. sanguineum, eyodinium impuaicum, Heterocapsa triquetra, Heterosipa akashiwo, Prorocentrum micans and Pyraminonas sp.. However no algicidal effects of Micrococcus sp. LG-5 were observed against Chlamydomonas sp., Cylindrotheoa closterium, P. mininum, P. triestimum, Pseudonieschia sp. and Sczipuiella trochoidea. On the other hand, algicidal activity on the tested marinelivefood was not detected except for Isochrysis galbana. In addition, physiological responses of cultured olive flounder (Paralichthys oliraceus) exposed to $1 and 10{\%}$ of the culture filtrate of Micrococcus sp. LG-5 were measured. There were no clear changes in AST, GGT, creatinine, urea, total cholesterol, total protein, albumine, $Mg^(+2), Ca^(+2), Na^+, K^+, and Cl^-$. These results indicate that olive flounders were not affected when they were exposed to the culture filtrate of Micrococcus sp. LG-5.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.1
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• pp.47-52
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• 2005

This study was conducted to evaluate the performance of submerged hollow fiber MF processes to treat secondary wastewater for water reuse. Specifically, membrane productivity and filtrate water quality were investigated under various operating conditions (i.e. flux, recovery, and backwash rate) at pilot-scale. Membrane fouling became more severe with increasing flux and recovery, suggesting that low flux operation (< 25 LMH) was desirable. At high flux operating(> 37.5 LMH), increasing backwash rate showed only limited success. The biofouling, quantified by PEPA and BFHPC, was also significant in wastewater reclamation, and biogrowth control by chlorine, were necessary to improve membrane productivity. Filtrate water qualities are in good compliance with water reuse regulations regardless of operating conditions (flux, recovery and backwash rate). Particle (e.g. turbidity) removal ranged from 89 to 98%, while only 11 to 21% of organics (e.g. NPDOC) were removed by MF membrane. Only small improvement in biostability (e.g. AOC) was achieved by MF system, and thus, without post disinfection, significant microorganisms might be present in the filtrate due to regrowth. Lastly, in order to further investigate pathogen removal, controlled microbial challenge tests were performed by monitoring Giardia, Cryptosporidium, bacteria and virus, and showed relatively good microbial removal.

• Membrane Journal
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• v.24 no.5
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• pp.350-357
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• 2014

Pressurized MF membranes are used to remove suspended solid and colloidal materials of wastewater treatment plant effluent as the pretreatment of RO in reuse water production process. Membrane operation data and pollutants removal efficiency are investigated using 100 t/d scale pilot plant in J wastewater treatment plant located in Namyangju city. 40 LMH flux of pressurized MF membrane are obtained in various turbidity and temperature condition. Coagulation of dissolved organic enables flux improvement of MF from 40 LMH to 60 LMH. Pressure drop of 1st RO elements rapidly increased after long-term pause, which is because the complex contamination of organic matter and ionic substances of pluming systems.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.5
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• pp.160-170
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• 2003

A pilot study was performed to examine the feasibility of intermittent slow sand filtration for agricultural reuse of reclaimed water. The effluent of biofilter for 16-unit apartment was used as influent to the slow sand filtration system at 0.6 $m^3$/day loading rate using 15 seconds spray in every 10 minutes on the about 1 $m^2$ surface area and 0.5 m depth. The influent concentrations of total coliform (TC), fecal coliform (FC) and E. coli were in the range of 10.000 MPN/100 mL. and they were reduced to less than 1,000 MPN/100 mL after filtration with average of 320, 270, and 154 MPN/100 mL, respectively, showing over 95 % removal. Turbidity and SS were improved effectively and their average concentration was reduced to 0.8 NTU and 1.7 mg/L, respectively, and removal rate was about 50 %. Average BOD and COD concentrations were also reduced substantially to 2.6 and 25.8 mg/L with about 55 and 21 % removal rate, respectively. Nutrients removal was relatively low and removal rate for T-N and T-P was low however, remaining nutrients might be beneficial and less concerned in case of agricultural reuse. The concentration of biofilter effluent used in this experiment was in the range of secondary treatment effluent but slightly stronger than the one from existing wastewater treatment plants (WWTPs). Therefore, intermittent slow sand filtration might be also applicable to the effluent from WWTPs as long as its agricultural reuse is available. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, the intermittent slow sand filtration was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water. This paper is a preliminary result from pilot study and further investigations are recommended on the optimum design parameters before full scale application.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.103-113
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• 2012

본 연구에서는 하수재이용에 따른 논에서의 토양염분 변화를 추정하기 위하여 경기도 화성시 수원환경사업소 인근에 위치한 병점지구를 대상으로 수문순환과 작물성장과의 관계를 고려한 SWAP (Soil-Water-Atmosphere-Plant) 모형을 이용하여 평가하였다. 실험에 사용한 관개용수는 지하수 (TR#1), 하수처리장 방류수+여과+UV (TR#3)로 분류하여 모형에 사용하였다. 유입관개수의 EC (Electrical Conductivity)는 지하수 관개수인 TR#1이 다른 처리구에 비해 작았고, TR#3의 경우 0.442~0.698 dS $m^{-1}$의 범위를 보였다. 모형의 보정과 검정을 위해서 대상지구에 FDR (Frequency Domain Reflection)을 설치하여 토양수분함유량과 염분농도를 토심에 따라 일단위로 모니터링 하였다. 토심 (50, 100, 140 cm)에 따른 토양함수량의 RMSE는 검정기간 중 TR#1에서 0.003~0.064 $cm^3\;cm^{-3}$, TR#3에서 0.001 $cm^3\;cm^{-3}$ 범위를 보여 주었고, 토양염분의 보정기간 중 토심별 RMSE는 TR#1에서 0.018~0.037 dS $m^{-1}$, TR#3에서 0.004~0.014 dS $m^{-1}$ 범위를 보여 적용성이 있는 것으로 나타났다. 토양내의 염분수지 분석 결과, 토양에서의 염분저장량이 (-)로 나타나 토양내로 침출되는 것으로 나타났으며, WMRI (Water Management Response Indicators)을 이용한 분석 결과, 높은 침투능으로 인하여 토양에서의 염분 집적 영향은 낮은 것으로 평가되었다.

• Journal of Korean Medical classics
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• v.18 no.2 s.29
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• pp.20-44
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• 2005

통과한의학화서양의학적원리연구심신적상호관계(通過韓醫學和西洋醫學的原理硏究心腎的相互關係), 득도료여하결론(得到了如下結論) 경연구심신지간재한의학상구유(經硏究心腎之間在韓醫學上具有): 심양여신음유'심신상교'적'수화기제'관계(心陽與腎陰有'心腎相交'的'水火旣濟'關係). 차외환유신양(명문화)여심양(심화)적상호의존관계(此外還有腎陽(命門火)與心陽(心火)的相互依存關係). 우유심장신여신장정적상호의존관계이지유신정충족시(又有心藏神與腎藏精的相互依存關係而只有腎精充足時), 재가이사심주신지적공능유지정상(才可以使心主神志的功能維持正常). 경연구심신지간재서양의학상구유(經硏究心腎之間在西洋醫學上具有): 제일(第一), 심장여신장재해부학상밀절연계(心臟與腎臟在解剖學上密切聯係), 즉종심장좌심실분지출신동맥(卽從心臟左心室分枝出腎動脈), 진이형성신소구등신장적혈관구화모세혈관강(進而形成腎小球等腎臟的血管球和毛細血管綱). 제이(第二), 심장향신장공응혈액(心臟向腎臟供應血液), 신장시인체중접수혈공최다적장기(腎臟是人體中接受血供最多的臟器). 제삼(第三), 심장통과심납소(ANP)적분비(的分泌), 증가신혈류양급신소체여과율(增加腎血流量及腎小體濾過率). 제사(第四), 신장통과신소(腎臟通過腎素)(renin)적분비조절혈압(的分泌調節血壓). 제오(第五), 신공능부전대심장구성부면영향(腎功能不全對心臟構成負面影響). 제육(第六), 심장여신장지간종서양의학적각도고려(心臟與腎臟之間從西洋醫學的角度考慮), 야존재착상생화상극관계(也存在着相生和相克關係). 경연구심신적상호관계재수행중적작용(經硏究心腎的相互關係在修行中的作用), 득출여하결론(得出如下結論): 제일(第一), 수행영인안정심지(修行令人安定心志), 사심화하강(使心火下降). 제이(第二), 수행시적호흡조절조폐금생신수(修行時的呼吸調節助肺金生腎水), 저시소유적수행법도재중시호흡조절적근본이유(這是所有的修行法都在重視呼吸調節的根本理由). 제삼(第三), 수행시발생수승화강(修行時發生水昇火降). 저실제상시의뢰심화중적일음효여신수중적일양효적발동내완성(這實際上是依賴心火中的一陰爻與腎水中的一陽爻的發動來完成). 제사(第四), 통과수행(通過修行), 가이달도보정적목적(可以達到保精的目的), 유차보장생명적지보(由此保藏生命的至寶). 제오(第五), 통과수행(通過修行), 가이달도연정화기(可以達到煉精化氣), 약능주도연정화기(若能做到煉精化氣), 가사인체불누설정액(可使人體不漏泄精液), 반이화기이증강인체기능(反而化氣以增强人體機能), 시보정적유효수단(是保精的有效手段). 수행적관건시'남자수성불누정(修行的關鍵是'男子修成不漏精), 여자수성온불누경(女子修成不漏經)'.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.838-842
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• 1999

In order to reclaim the effluent discharged from sewage treatment facilities application of an irradiation technique was investigated in this study for industrial water reuse. Samples were filtered using a sand filter to remove particles. Co-60 was used as an irradiation source and the irradiation dose was varied from 0.1 kGy to 15 kGy. The major source of colour in secondary treatment effluent was humic substances, which could be easily removed by irradiation with a dose 5 kGy. Bacteria could be also disinfected even at low doses. It was possible to get high quality water for industrial water reuse. But the effluent still contained a small amount of organic compounds. Further treatment, of residual organic compounds will be necessry if the higher quality water is required.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.281-288
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• 2002

Crab shell 충진 칼럼을 이용한 수중 중금속의 연속적 제거에 있어서 다른 흡착제 (CER, GAC, Zeolite)와 비교 실험을 통하여 crab shell의 중금속 제거능을 알아보았다. 수중 $Pb^2+/{2+}$ 의 column을 이용한 연속적제거에 있어서 미세침전부분이 외부로 배출됨으로 칼럼 외부에 여과시스템의 도입함으로써 중금속 제거능을 높일 수 있을 것으로 판단된다. 중금속의 연속적 제거에 있어서 CER의 1,000 BVs까지의 전체 제거량은 0.35mmol/g, GAC는 0.17mmo1/g, zeolite는 0.16 mmol/g으로 나타났고 crab shell에 의한 중금속 제거량은 0.61 mmol/g으로 다른 흡착제보다 높은 제거효율을 보였다. 수중 중금속의 연속적 제거에 있어서 여러 흡착제의 제거 순서는 crab shell > CER > GAC > zeolite 로 나타났다. Crab shell의 경우는 파과점이 2,000 BVs에서 나타나므로 일반적인 폐수처리의 화학적 처리 후 잔존하는 저농도의 중금속을 제거를 위해 crab shell 충진 칼럼이 유용 할 것으로 판단된다. Crab shell의 재사용 가능성을 알아보기 위하여 crab shell을 이용한 중금속 제거공정에서 연속적인 중금속제거와 탈착과정을 통하여 보았을 때 1회에서 $Pb^2+/{2+}$제거된 량은 0.71 mmol/g 제거되었고 2회에서는 0.27 mmol/g, 3회에서는 0.02 mmol/g으로 급격하게 crab shell의 제거능이 떨어지는 것을 관찰 할 수 있다. 이는 crab shell이 재사용이 불가능 할 것으로 판단되나 다른 흡착제보다 월등한 제거효율을 보이므로 수중 중금속의 연속적 제거 흡착제 적합할 것으로 판단된다.

• Journal of the Korean Ceramic Society
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• v.35 no.3
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• pp.209-218
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• 1998

Ca-deficiency frequently observed in the hydroxyapatite powders prepared by precipitation which is known to be deleterious for its application to biomaterials was prevented by the technique developed in this study. In addition the prepared powder has been revealed to be quite active that full density is achieved at temperatures as low as 100$0^{\circ}C$ Instead of using N2 air was chosen as the processing atmosphere during the precipitation and aging of hydroxyapatite. {{{{ {CO }`_{3 } ^{2- } }} ions from the processing atmosphere(air) substitute partly for {{{{ {PO }`_{4 } ^{3- } }} ions in the hydroxyapatite and its content can be controlled by pH of the solution where the pre-cipitation reaction occurs.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.293-296
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• 2008

적조발생 해역인 울진 연안의 해수에서 분리한 100여종의 해양미생물 중 8 균주가 C. polykrikoides에 대해 살조활성을 나타내었으며, 이 중 살조활성이 가장 우수한 Brachybacterium sp. SY-97을 선별하였다. Brachybacterium sp. SY-97의 최적 배양조건은 30$^{\circ}C$, pH 7.0, 2.0% NaCl 농도였다. Brachybacterium sp. SY-97은 C. polykrikoides를 살조시킨 후 생성되는 EOM을 이용하여 성장하며, 유도기를 거쳐 대수증식기에 살조물질을 활발히 생산하는 것으로 판단된다. 0.2 $\mu$m의 Cell Culture Insert를 삽입한 2조 배양계를 이용하여 Brachybacterium sp. SY-97의 살조 유형을 조사한 결과, Brachybacterium sp. SY-97은 0.2 $\mu$m filter에 의해 C. polykrikoides와 격리된 상태에서도 C. polykrikoides를 살조시켜 직접 공격형이 아니라 세포외로 물질을 분비하여 살조시키는 살조인자 분비형으로 밝혀졌다. Brachybacterium sp. SY-97의 배양여과액의 첨가 농도별 살조활성을 측정한 결과, 15%의 경우 C. polykrikoides의 개체수는 급격히 감소하여 12시간 후에 100% 살조되었고, 10%의 경우 15시간 후에 모두 살조되었고, 5%의 경우 18시간 후에 control에 비해 90% 이상 살조 되었다.