• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.409-414
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• 2006

Sulfur-oxidizing bacteria were enumerated and isolated from a steady-state anaerobic master culture reactor (MCR) operated for over six months under a semi-continuous mode and nitrate-limiting conditions using thiosulfate as an electron donor. Most are Gram-negative bacteria, which have sizes up to 12 m. Strains AD1 and AD2 were isolated from the plate count agar (PCA), and strains BD1 and BD2 from the solid thiosulfate/nitrate medium. Based on the morphological, physiological, FAME and 16S rDNA sequence analyses, the two dominant strains, AD1 and AD2, were identified as Paracoccus denitrificans and Paracoccus versutus (formerly Thiobacillus versutus), respectively. From the physiological results, glucose was assimilated by both strains AD1 and AD2. Heterotrophic growth of strains AD1 and AD2 could be a more efficient way of obtaining a greater amount of biomass for use as an inoculum. Even though facultative autotrophic bacteria grow under heterotrophic conditions, autotrophic denitrification would not be reduced.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.49-61
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• 2019

Swine manure has been recognized as a organic sources for composting and many research was conducted to efficiently utilize and treat. This study was to evaluate a feasibility for producing swine manure compost under various treatment with mixture of swine manure and saw dust. Treatments were designed as follows; non aerated composting pile(REF), aerated composting pile of $100L/m^3$(EXP1), and aerated composting pile of $150L/m^3$(EXP2). The total days of fermentation were 28 days and each samples were collected at every 7 days from starting of composting. Temperature sensors were installed under 30~40cm from the surface of composting pile. Inner temperature in composting piles of EXP1 and EXP2 was rapidly increased to $67{\sim}75^{\circ}C$ within 1~2 days. The elevated temperatures found during the thermophilic phase are essential for rapid degradation of organic materials. While swine manure composted, moisture content, total nitrogen, EC of EXP1, EXP2 in sample at 28 days were lower than those of REF. But, pH and organic matter of EXP1, EXP2 in sample at 28 days were higher than those of REF. After finishing fermentation experiment, maturity was evaluated with germination test. Calculated germination index(GI) at REF, EXP1 and EXP2 were 23.49, 68.50 and 51.81, respectively. The values of germination index were higher at EXP1 and EXP2 which is aerated composting piles than REF which is non aerated composting pile. According to the results, composting process by aerated static pile compost had significant effect on the reduction of required period for composting. Supplying adequate amount of air to compost swine manure will greatly reduce composting period.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.123-130
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• 2006

Principal aim of this study is to suggest the statistical equation model which can predict an amount of ammonia emission according to the degree of compost maturity during composting livestock manure. Composting process was classified with intial, midterm and final phase based on germination index of compost samples. Total Kjeldahl nitrogen(TKN) and organic matter(OM) were selected as the independent variables available to contribute to ammonia emission from composting pile. Ammonia concentration measured in the samples taken at the intial phase was about 10ppm, sharply increased to 50ppm at the midterm phase, and gradually decreased to about 10ppm. The contents of Total Kjeldahl nitrogen and organic matter through whole composting period were ranged from 0.6 to 1.2% and from 30 to 40%, respectively, were reduced slightly at the midterm phase, but generally showed no constant fluctuation pattern. In estimating ammonia emission with application of the statistical equation model, the coefficients of independent variables at the midterm phase when an average concentration of ammonia was highest showed a relatively high values whereas those at the initial phase when an that of ammonia was lowest indicated a relatively low values. However, no statistical significance was found in the coefficients of independent variables and the equation model. Additionally, the further research, which can include the considerable analysis data with more samples taken than this study, is needed in order to suggest the statistically significant equation model available to predict ammonia emission during composting process.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.605-622
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• 2007

Elemental, Rock-Eval pyrolysis and isotopic analysis of the core sediments from the northwestern and eastern Ulleung Basin of the East were carried out to identify their geochemical characteristics, spatial and vertical variation and origin of organic matter in Upper Quaternary sediments from the northwestern and eastern Ulleung Basin of the East Sea. TOC, m and TS did not show spatial variation between the sampling locations whereas they showed systematic vertical variation associated with MIS stages related to the sea-level change of the East Sea. It is suggested that these past changes of sea-level influenced the sedimentary depositional environments and/or diagenesis which resulted the patterns observed in this study. Based on the results of TOC/N, TS/TOC, ${\delta}^{13}C_{org}\;and\;{\delta}^{15}N_{org}$ analysis, organic matters in the study area appears to be predominantly originated from the marine algae rather than land plant and deposited under normal marine oxic condition during MIS I and MIS III period, and under euxinic/anoxic condition during MIS II period. TOC/N, ${\delta}^{13}C_{org}\;and\;{\delta}^{15}N_{org}$ have a relatively constant value irrespective of MIS stages, implying that the organic matter source does not change by the sea-level fluctuations. However, the results of Rock-Eval pyrolysis indicates that the organic matter is in immature stage and originated from land-plant (Type III), locating in the immature stage land plant (Type III). Similar differences were reported from other areas such as the Atlantic Ocean, Iberia Abyssal Plain, Mediterranean Sea, suggesting that Rock-Eval method does not exactly reflect the characteristic of immature organic matters. Accordingly, the application of Rock-Eval pyrolysis for delineating the source of immature organic matters should be approached with caution and all other geochemical proxies should be considered altogether at the same time.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.173-179
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• 1997

출발원료로 ferric nitrate, ethylene glycol, acethyl acetone 혼합용액을 사용하여 dip-coating된 $\alpha$-Fe$_2$O$_3$막을 제조하였다. coating을 위한 혼합용액의 시간의 경과에 따른 용액내의 가교(polymerization) 효과를 관찰하기 위해서 적외선 분광기(FT-IR)을 사용하였고, 막 형성 시 유기물 분해 및 결정화 시작 온도를 확인하기 위하여 FT-IR, XRD, DSC 등을 이용하여 분석을 행하였다. 또한 각 조건에서 제조된 막은 X-선 회절 분석을 통해 결정상을 확인 하였으며, SEM을 통하여 막의 두께 변화에 대하여 관찰하였다.

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.163-164
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• 2008

• The Microorganisms and Industry
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• v.16 no.2
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• pp.14-16
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• 1990

미생물을 이용한 광물의 제련(microbial leaching)은 미생물의 몇가지 기전에 의해 광물성 sulfide를 산화시킴으로써 금속을 수용화시키는 과정이다. 이 방법은 현재는 구리나 우라늄 제련에 이용되고 있으며 광물질에 금속의 함량이 낮을 때 재래적 화학적 처리로 제련하는 것에 비해 훨씬 경제적이므로 앞으로의 자원획득문제에 기술적 및 생태적 중요성을 갖고 있다. 본 연구에서는 호산성의 Thiobacilli와 같은 biotope에 생존하는 종속영양미생물을 분리한 후 혼합 배양을 통해 Thiobacilli의 일차 생산자로서의 역할및 이때 생성된 유기물의 영향및 종속영양 미생물이 Thiobacilli에 미치는 영향에 대해 조사하고자 하였다.

• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.150-160
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• 1993

농업폐기물중 유기물이 상당부분인 축산폐기물(분뇨)는 하천의 수질악화, 호소의 부영양화 및 지하수오염 등의 자연환경오염의 주범중의 하나로 잘 알려져 있다. 그러나 축산폐기물은 그 처리방법에 따라서 환경오염을 줄일 뿐만 아니라, 적정공정을 통하여 퇴비화에 의한 자원화가 가능하다는 것은 이미 알려진 사실이다. 대체적으로 기초적이며 공통적인 부분에 관한 축산폐기물 처리시설 및 공정체계는 이미 제품화가 되어 가동중에 있고, 단지 지역적 특성이나 다양한 규모의 제약조건하에서 실행가능한 중소규모 시설에 관해서는 일련의 실험들을 통하여 개발ㆍ적응해 나가고 있는 추세라 할 수 있겠다.(중략)

• Environmental engineer
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• s.184
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• pp.64-69
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• 2001

1998년 기준으로 하수처리장에서 발생하는 슬러지는 약 144만톤/년으로 발생량 대부분을 단순매립과 해양투기로 처리하고 있어서, 각종 규제가 강화됨에 따라 처리방안에 대한 대안 마련이 시급한 실정이다. 특히 단순매립 시에는 슬러지 대부분이 유기물로 부패되어 매립지 내에서 악취, 침출수, 해충 등의 2차 환경오염을 야기시키고 있다. 따라서 본 연구개발의 목표는 자가발열 고온호기성 소화(Autothermal Thermophilic Aerobic Digest

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.409-410
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• 2001

악취 발생원은 하수ㆍ분뇨처리장, 매립지 등 각종 환경기초시설에서부터 석유화학단지, 각종 산업시설, 그리고 농촌의 축사에 이르기까지 우리 생활주변에 널리 분포되어 있다. 탈취시설은 일반적으로 분뇨처리장을 제외하고는 보편화되어 있지 않으며, 특히 일반 농촌 축사의 경우는 탈취 시설이 전무한 상태로서 축사에서 발생하는 악취로 인한 주민 민원 발생이 증가하고 있다. 특히 축분의 대사과정에서 주로 발생되는 악취인 암모니아는 강한 악취성분의 하나로 배설된 분뇨에서 미생물의 유기물 분해에 의해 암모늄이 생성되고, 생성된 암모늄은 암모니아 가스로 대기중으로 휘산되어 강한 악취를 발생시킨다.$^{1)}$ (중략)