• Title/Summary/Keyword: Environmental Degradation

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Monitoring 4-Chlorobiphenyl-Degrading Bacteria in Soil Microcosms by Competitive Quantitative PCR

  • Lee, Soo-Youn;Song, Min-Sup;You, Kyung-Man;Kim, Bae-Hoon;Bang, Seong-Ho;Lee, In-Soo;Kim, Chi-Kyung;Park, Yong-Keun
    • Journal of Microbiology
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    • v.40 no.4
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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.

Effect of MCM-41 Preparation Methods on the Kinetics of Catalytic Pyrolysis of Linear Low Density Polyethylene (MCM-41 촉매 합성법이 선형 저밀도 폴리에틸렌의 촉매 열분해 동역학에 미치는 영향)

  • Park Young-Kwon;Kim Joo-Sik;Jeon Jong-Ki;Lim Jung Eun;Kim Ji Man;Yoo Kyung-Seun
    • Polymer(Korea)
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    • v.29 no.2
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    • pp.122-126
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    • 2005
  • The effect of Al-MCM-41 preparation methods on the catalytic degradation of linear low density polyethylene (LLDPE) was investigated. Al-MCM-41 catalysts were synthesized by direct method (Al-MCM-41-D) and post treatment method (Al-MCM-41-P) and their characteristics were elucidated by XRD, BET, $NH_3\;TPD,\;^{27}Al$ MAS NMR. TGA kinetic analysis showed that the catalytic activation energies of Al-MCM-41-D and Al-MCM-41-P were 191.54 and 114.26 kJ/mol, respectively. The higher catalytic activity of Al-MCM-41-P would be attributed to its smaller pore size as well as higher number of acid sites that are accessible.

A Study on Estimations and Long-term Forecasts of SO$_2$ Pollution in Each City & County of Korea (시군별 이산화황(SO$_2$) 오염도의 현황 진단과 장기 예측에 관한 연구)

  • 김용준
    • Journal of Korean Society for Atmospheric Environment
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    • v.13 no.1
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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.

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Evaluation of Applicability of the ESTIMATOR Model for the Analysis of Nutrient Load Characteristics

  • Shin, Yong-Chul;Heo, Sung-Gu;Lim, Kyoung-Jae;Choi, Joong-Dae
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.7
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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.

An Assessment on Harmonics Effect in Customer and the Distributed Power System during Grid Connection of Residential Fuel Cell System (가정용 연료전지 시스템의 계통연계 시 수용가 및 배전계통에서의 고조파 영향 평가)

  • Park, Chan-Eom;Jung, Jin-Soo;Han, Woon-Ki
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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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.

Trend on the Recycling Technologies for Spent fluorescent lamps by the Patent and Paper Analysis (특허(特許)와 논문(論文)으로 본 폐 형광램프 재활용(再活用) 기술(技術) 동향(動向))

  • Rhee, Seung-Whee;Park, Hun-Su;Cho, Young-Ju;Cho, Bong-Gyoo
    • Resources Recycling
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    • v.21 no.4
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    • pp.76-85
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    • 2012
  • Fluorescent lamps generally involve mercury within their lamp bulbs. Thus if the lamps are disposed as they are, it might cause environmental pollution. On the other hand, as the life of the lamps depends on the degradation of the discharge performance, the fluorescent substance composing the fluorescent substance coating can be recycled by reusing them as the recycled fluorescent substance. Also, the glass material composing the glass bulbs can be reused. The range of search was limited in the open patents of USA (US), European Union (EU), Japan (JP), Korea (KR) and SCI journals from 1977 to 2011. Patents and journals were collected using key-words searching and filtered by filtering criteria. The trends of the patents and journals was analyzed by the years, countries, companies, and technologies. Recovery method of metals from spent fluorescent lamps is mainly the focus on the recovery of precious metals using acid treatment and, detoxification technology is related with controlling process of mercury using a filter system.

Landscape changes in suburban villages resulting from plant locations (공장입지에 따른 대도시 근교지역 농촌마을의 경관변화 특징)

  • Son, Yong-Hoon;Lee, Cha-Hee;Saito, Yukihiko
    • Journal of Korean Society of Rural Planning
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    • v.20 no.1
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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.

A Study on Application of Port Hinterland by a Space Port City Interface Characteristics (항만도시 인터페이스 공간특성에 의한 항만배후단지 활용방안)

  • Hwang, Sun Ah;Kim, Jong Gu;Hong, Ji Su
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.169-180
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    • 2016
  • The spaces of port and urban in a Port City have different space characteristics substantially, but those are required to be developed interdependently. Degradation and loss of the sense of place in the existing spaces caused by decline of natural function have an adverse effect on the revival of local economy as well as make worse image of the entire city. In some developed countries, therefore, many researches on the port spaces lagging behind the times due to changes of the characteristics and function of port spaces have been conducted continuously for a long time. This study aims at seeking a device how the domestic hinterland could be utilized as efficient spaces having the characteristics of outskirts space and port city interface through the application of characteristics of the interface space of port city, capable of playing a role as buffer zone between the port space and the city space.

Differential Proteomic Analysis of Secreted Proteins from Cutinase-producing Bacillus sp. SB-007

  • Ban, Yeon-Hee;Jeon, Mi-Ri;Yoon, Ji-Hee;Park, Jae-Min;Um, Hyun-Ju;Kim, Dae-Soon;Jung, Seung-Ki;Kim, Keun-Young;Lee, Jee-Won;Min, Ji-Ho;Kim, Yang-Hoon
    • The Plant Pathology Journal
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    • v.24 no.2
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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.

Deterioration Diagnosis and Petrogenesis for Rock Properties of the Stone Lantern in the Gwanchoksa Temple, Nonsan, Korea (논산 관촉사 석등의 훼손도 진단 및 기원암의 성인적 해석)

  • Lee, Myeong Seong;Yi, Jeong Eun;Pyo, Su Hee;Song, Chi Young;Lee, Chan Hee
    • Journal of Conservation Science
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    • v.17 s.17
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    • pp.5-18
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    • 2005
  • Rock materials of the Stone Lantern in the Gwanchoksa temple was composed of dark grey granodiorite. This Stone Lantern is partly structural distortion as S-shape, especially, rocks of the upper supports and under the roof materials were highly deterioration due to the surface exfoliation, and strong secondary contaminations owing to the discoloration by oxidation of inserted iron plates between the rock properties, and white grey to dark black contaminants along the rain path way. Rock surface of the Stone Lantern occurred as partly green patches because of coated by algae, lichen and moss. This biological problems are need for cleaning and treatments. The Stone Lantern have to be considered to conservation method that can reduce weathering factors with long-term monitoring about environmental change for structural stability, surface degradation and mechanical weathering. Materials of the Stone Lantern and basement rocks of the area are consisted of same petrogenetic granodiotite based on occurrences, petrological and geochemical characteristics.

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