• Journal of Microbiology
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• 제40권4호
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• pp.274-281
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• 2002

The competitive quantitative PCR method targeting pcbC gene was developed for monitoring 4-chlorobiphenyl(4CB)-degrading bacteria, Pseudomonas sp. strain DJ-12, in soil microcosms. The method involves extraction of DNA from soil contaminated with 4CB, PCR amplification of a pcbC gene fragment from the introduced strain with a set of strain-specific primers, and quantification of the elec-trophoresed PCR product by densitometry. To test the adequacy of the method, Pseudomonas sp. strain DJ-12 was introduced into both contaminated and non-contaminated soil microcosms amended with 4CB. Pseudomonas sp. strain DJ-12 was monitored and quantified by a competitive quantitative PCR in comparison with 4CB degradation and the result was compared to those obtained by using the conventional cultivation method. We successfully detected and monitored 4CB-degrading bacteria in each microcosm and found a significant linear relationship between the number of 4CB-degrading bacteria and the capacity for 4CB biodegradation. The results of DNA spiking and cell-spreading experiments suggest that this competitive quantitative PCR method targeting the pcbC gene for monitoring 4CB- degrading bacteria appears to be rapid, sensitive and more suitable than the microbiological approach in estimating the capacity of 4CB biodegradation in environmental samples.

• 폴리머
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• 제29권2호
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• pp.122-126
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• 2005

Al-MCM-41의 제조방법이 선형 저밀도 폴리에틸렌(LLDPE)의 촉매 분해 활성에 어떠한 영향을 주는지 조사하였다 이를 위해 Al-MCM41은 직접 합성법(Al-MCM41-D)과 후처리법(Al-MCM-41-P)의 두 가지 방법으로 제조되었으며, XRD, BET, $NH_3\;TPD,\;^{27}Al$ MAS NMR 등을 이용하여 이들 촉매 특성을 규명하였다. TGA 동역학 방법을 사용하여 Al-MCM-41-D와 Al-MCM-41-P의 LLDPE촉매 분해 활성화 에너지를 구한 결과 각각 197.54, 174.26 kJ/mol로 나타났다. 이처럼 시-MCM-41-P가 시-MCM-41-D보다 촉매 활성이 높은 이유는 접근 가능한 산점수가 훨씬 많고 상대적으로 기공 크기도 작은 것에 기인한 것으로 여겨진다.

• 한국대기환경학회지
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• 제13권1호
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• pp.19-29
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• 1997

It is more likely that the degree of air quality degradation that we have faced would be much lessen, if integrated management of air pollution control and assessment had been fully enforced by the local administrations, not by the centralized environmental agency in the first place. As the selfgoverning local administrations have been established since 1995, the need for air quality control by the local administration or local agency is getting the ground. However, in practice, air quality control by the local administration rarely put into effect due to lack of basic data which cover the present trends of air quality in each local city or county and are necessary for decision making. The emissions of SO$_2$ in each city and county of Korea in 1993 were calculated in this study, based on energy consumptions and emission factors. The ambient concentrations of SO$_2$ also were estimated by applying modified Miller-Holtzworth model. Observed and estimated concentrations of SO$_2$ showed that about 17.5 percents of cities and counties in the country were more polluted than the target value, 20ppb/year. The emissions and ambient concentrations of SO$_2$ in each city and county in 2000, 2005, and 2010 were also forecasted, assumed business as usual senario. It was shown that, in 2010, the emissions of SO$_2$ will be 2.8 times more than those of 1993 and much of them are from industrial sector. Also shown that 38.3 percents of cities and counties will be more polluted than the target value and most of them are polluted areas in 1993. The methods and results of this study could be used in developing the efficient reduction strategies in each city and county.

• 한국농공학회논문집
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• 제47권7호
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• pp.67-75
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• 2005

It has been well-known that the Nonpoint Source (NPS) pollutions are the primary contributors to water quality degradation in the receiving water bodies as well as the Point Source (PS) pollutions. To develop an effective management practice for water quality improvement, pollutant loads must be first estimated. In many studies, the Numeric Integration (NI) method has been used because of its ease of application, irrespective of the total number of samples collected for each storm event. Thus, there have been needs for more accurate pollutant load estimation with a limited number of water quality samples. In this study, NI method and regression method using the USGS ESTIMATOR model were comparatively used to calculate the pollutant loads for the Wolgokri watershed, Gangwon Province. The $NO_{3}$-N, T-N, and T-P loads using NI method and ESTIMATOR model were 13.85 kg/ha, 45.92 kg/ha, and 1.887 kg/ha, and 11.93 kg/ha,43.20 kg/ha, and 1.650 kg/ha, respectively. The estimated loads using ESTIMATOR model were lower than those using NI method by $86\%$, $94\%$, and $87\%$. These discrepancies in the estimated loads using a different load estimation method could be explained in that the total number of samples were not sufficient enough for NI method. Thus, ESTIMATOR model is recommended for the frequently stream discharge and less frequently measured water quality data.

• 전기학회논문지
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• 제60권6호
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• pp.1280-1285
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• 2011

Recently, due to the use of fossil fuels for electric power production, carbon emissions increased excessively. Thereby, in order to replace fossil fuels, many studies about fossil fuels such as solar and fuel cell energy source are progressing. Fuel cell system has high energy conversion efficiency. Also, fuel cell system is environmentally friendly system because the carbon emission is almost not occur. Therefore, the fuel cell system is considered as the core technology of in the fields of the future energy and environmental. Fuel cell system has an effect on distribution power system because another power source of other than large power plants. So, fuel cell system can be degradation reason of power quality in the power system. In this paper, we constructed the system for an assessment on harmonics effect. The system is composed with power source, harmonics generation and linear load, fuel cell system. we also performed assessment on harmonics effect in customer and the distributed power system during grid connection of residential fuel cell system. An assessment cases are divided into three. A Case 1 is state that residential load and fuel system are connected to grid, Case 2 is state that residential load and harmonics load are connected to grid, and Case 3 is state that all loads are connected to grid. As a output of fuel cell system is increase, analysis results based on assessment system showed that power quality became more aggravation as effect of harmonics.

• 자원리싸이클링
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• 제21권4호
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• pp.76-85
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• 2012

조명기기는 일반적으로 램프벌브 내에 수은을 포함하고 있기 때문에 그대로 폐기하면 환경오염 등을 야기하는 우려가 있다. 한편, 조명기기의 수명은 방전특성의 저하 등에 근거하기 때문에 형광체층의 구성 재료인 형광체는 회수, 재생함으로써 재생형광체로서 재이용할 수가 있다. 또한, 유리벌브를 구성하는 유리재료에 관해서도 재이용이 가능하다. 본 연구에서는 폐조명기기의 재활용기술에 대한 특허와 논문을 분석하였다. 분석범위는 1977년~2011년까지의 미국, 유럽연합(EU), 일본, 한국의 등록/공개된 특허와 SCI 논문으로 제한하였다. 특허와 논문은 키워드를 사용하여 수집하였고, 기술의 정의에 의해 필터링하였으며 특허와 논문의 동향은 연도, 국가, 기업, 기술에 따라 분석하여 나타내었다. 폐조명기기로부터 금속을 회수하는 방법으로 산에 침지시켜 희토류 금속을 회수하는 기술이 주종이었으며 무해화 기술은 필터를 이용하여 수은을 제어하는 기술이 대부분이었다.

• 농촌계획
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• 제20권1호
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• pp.13-26
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• 2014

The purpose of this study is to identify characteristics of the landscape changes in Gwangjyu city and Icheon city, the suburban areas on the outskirts of the Seoul metropolitan area, by focusing on the causes of the urban sprawl and the resultant morphological characteristics of landscape degradation. Particular attention has been given to the 'advantages for developing suburb including geographical proximity and land price', 'institutional regulation such as land-use regulation' and 'community solidarity' as drivers for possible introduction of external factors. The types of landscape change were divided into three, after having on-the-ground research on eleven chosen towns and interviews with head of a village: Overwhelming Change, Separated and Small-Scale Change. It was found that, in general, the quality of landscape was best for the small-scale change type, followed by separated and overwhelming change types. While the types of landscape change are correlated with the geographical proximity, its relevance with land regulation is relatively weak. The study found that imposing a land-use regulation as a means to prevent changes in suburban village landscape may not be fully effective. Also it analyzed that villages could better manage with keen interest the surrounding landscape if there is a high degree of solidarity within the village community. Therefore, the sense of community could play an important complementary role to land-use regulation which does not suffice in itself to manage suburban landscape.

• 대한토목학회논문집
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• 제36권1호
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• pp.169-180
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• 2016

항구도시에서 항만과 도시공간은 상이한 공간특성을 가지고 있지만 서로 상호의존적으로 발전되어 나가야 한다. 기능쇠퇴로 인한 기존 공간의 장소성 상실과 기능 저하는 도시 전체의 이미지를 나쁘게 만들 뿐만 아니라 나아가 지역 경제부흥에도 좋지 않은 영향을 미치고 있다. 이에 일부 선진국에서는 시대변화에 따른 항만공간 특성 및 기능의 변화로 인해 낙후되어가는 항만공간에 대한 연구를 오래전부터 지속적으로 진행해 오고 있다. 본 연구에서는 항만배후단지에 항만과 도시공간 사이의 완충지 역할을 할 수 있는 항만도시 인터페이스 공간의 특성 적용하여 향후 국내 항만배후단지가 주변 공간특성과 항만도시 인터페이스 특성이 부여된 효율적인 공간으로 활용되기 위한 방안을 모색하고자 한다.

• The Plant Pathology Journal
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• 제24권2호
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• pp.191-201
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• 2008

Bacillus sp. SB-007 was isolated from pea leaves harvested from the southwestern parts of South Korea through screening on a minimal medium containing 0.2% purified cutin for its ability to induce the cutinase production. However, no cutinase was produced when it was grown in a minimal medium containing 0.2% glucose. A proteomic approach was applied to separate and characterize these differentially secreted proteins. The expression level of 83 extracellular proteins of the cutinase-producing Bacillus sp. strain SB-007 incubated in a cutinase-induced medium increased significantly as compared with that cultured in a non cutinase-induced medium containing glucose. The extracellular proteome of Bacillus sp. SB-007 includes proteins from different functional classes, such as enzymes for the degradation of various macromolecules, proteins involved in energy metabolism, sporulation, transport/binding proteins and lipoproteins, stress inducible proteins, several cellular molecule biosynthetic pathways and catabolism, and some proteins with an as yet unknown function. In addition, the two protein spots showed little similarities with the known lipolytic enzymes in the database. These secreted proteome analysis results are expected to be useful in improving the Bacillus strains for the production of industrial cutinases.

• 보존과학회지
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• 제17권
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• pp.5-18
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• 2005

논산 관촉사 석등은 암회색을 띠는 화강섬록암으로 구성되어 있다 이 석등은 전체적으로 S자형으로 뒤틀려 있으며 상대석과 1층 옥개석 하부에는 표면박리가 발생하여 석재의 표면이 심하게 부서지고 있다. 이차적 오염도 심각하여 . 부재사이에 삽입된 철편의 산화에 의한 변색과 강수의 유동흔적을 따라 나타나는 회백색 및 암흑색의 침전물이 산재한다. 석등의 표면에는 지의류와 선태류가 피복되어 있어 다양한 형태의 생물학적 훼손을 저감하기 위한 보존처리가 요구된다 또한 석등의 구조적 안정과 표면마모 및 기계적 풍화를 저지하기 위해 환경변화에 대한 장기적인 모니터 링과 함께 풍화요소를 저감할 수 있는 보존방법을 강구해야 할 것이다. 이 석등의 부재는 산출상태와 암석학적 및 지구화학적 특성이 주변의 기반암과 동일한 성인을 갖는 것으로 보아 주변의 석재를 이용하여 석등을 제작하였을 가능성이 높다.