• Title/Summary/Keyword: Potential source

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Characteristics of N2O Emission Factor and Measurements from Gasoline-Powered Passenger Vehicles (국내휘발유 승용차량으로부터의 N2O배출인자 특성연구)

  • Kim, Deug-Soo;Ryu, Jeong-Ho;Yoo, Young-Sook;Jung, Sung-Woon;Kim, Dae-Wook
    • Journal of Environmental Science International
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    • v.16 no.2
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    • pp.179-185
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    • 2007
  • Nitrous oxide ($N_2O$) is an important trace gas in the atmosphere not only because of its large global warming potential (GWP) but also because of the role in the ozone depletion in the stratosphere. It has been known that soil is the largest natural source of $N_2O$ in global emission. However, anthropogenic sources contributing from industrial section is likely to increase with rising the energy consumption, and transportation as well. In this study, a total of 32 gasoline-powered passenger vehicles (ranging from small to large engine's displacement and also ranging from aged catalyst to new catalyst) were tested on the chassis dynamometer system in order to elucidate the characteristics of $N_2O$ emission from automobiles under different driving modes. Ten different driving modes developed by NIER were adapted for the test. The results show that the $N_2O$ emission decreases logarithmically with increase of vehicle speed over the all test vehicles ($N_2O$) emission = -0.062 Ln (vehicle speed) + $0.289,\;r^2=0.97$). It revealed that the larger engine's displacement, the more $N_2O$ emission were recorded. The correlation between $N_2O$ emission and catalyst aging was examined. It found that the vehicles with aged catalyst (odometer record more than 8,0000km) emit more $N_2O$ than those with new catalyst. Average $N_2O$ emission was $0.086{\pm}0.095\;N_2O-g/km$ (number of samples=210) for the all test vehicles over the test driving modes.

Screening of Antibacterial Agent Against Streptococcus mutans from Natural and Medicinal Plants, (자생 및 약용 식물의 Streptococcus mutans항균 활성의 검색)

  • Kim Kun-Woo;Baek Jueng-Kuy;tang Young-Wook;Kum Eun-Joo;Kwon Yun-Suk;Kim Hong-Ju;Sohn Ho-Yong
    • Journal of Life Science
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    • v.15 no.5 s.72
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    • pp.715-725
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    • 2005
  • Oral streptococci are major constituents of dental plaques, and their prevalence is closely linked with various pathologic symptoms, such as dental caries. To develop natural anticaries agent, we prepared 309 kinds of plant extracts from 215 species of edible or medical plants, and antibacterial activity of the extracts against Streptococcus mutans JC-2 were evaluated based on 96 well microtiter plate assay and disk paper method, subsequently. Among the tested plant extracts, Ailanthus altissima, Paeonia lactiflora, Rubus phoenicolasius, Aralia continentalis, Quercus acutissima, Persicaria hydropiper and Agrimonia pilosa extracts showed strong antimicrobial activity. Determination of minimal inhibitory concentration (MIC) of the selected seven plant extracts showed that Ailanthus altissima, Persicaria hydropiper and Quercus acutissima extracts ($MIC=25\∼30[\mu}g/ml$) has potential as a source of natural anticaries agents.

Development of GIS Based Wetland Inventory and Its Use (GIS에 기반한 습지목록의 제작과 활용)

  • Yi, Gi-Chul;Lee, Jae-Won;Kim, Yong-Suk
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.1
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    • pp.50-61
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    • 2010
  • This study was carried out to find out the way to build a comprehensive wetland ecosystem database using the technique of remote sensing and Geographic Information System. A Landsat TM image (taken in Oct. 30, 2002), Kompsat-2 images (Jan. 17, 2008 & Nov. 20, 2008), LiDAR(Mar. 1, 2009) were used for the primary source for the image analysis. Field surveys were conducted March to August of 2009 to help image analysis and examine the results. An actual wetland vegetation map was created based on the field survey. Satellite images were analyzed by unsupervised and supervised classification methods and finally categorized into such classes as Phragmites australis community, mixed community, sand beach, Scirpus planiculmis community and non-vegetation intertidal area. The map of wetland productivity was developed based on the productivity of Phragmites australis and the relationship to the proximity of adjacent water bodies. The developed 3 dimensional wetland map showed such several potential applications as flood inundation, birds flyway viewsheds and benthos distribution. Considering these results, we concluded that it is possible to use the remote sensing and GIS techniques for producing wetland ecosystem spatial database and these techniques are very effective for the development of the national wetland inventory in Korea.

Ecological Risk Assessment of Pharmaceuticals in the Surface Water Near a Pharmaceutical Manufacturing Complex in Korea (제약단지 인접 지역 지표수의 잔류 의약물질 생태위해성평가)

  • Park, Suhyun;Kang, Habyeong;Shin, Hyesoo;Ryoo, Ilhan;Choi, Kyungho;Kho, Younglim;Park, Kyunghwa;Kim, Kyungtae;Ji, Kyunghee
    • Journal of Environmental Health Sciences
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    • v.46 no.1
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    • pp.45-64
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    • 2020
  • Objectives: Limited information is available on the presence and associated ecological risks of pharmaceutical residues in aquatic environments near pharmaceutical manufacturing areas in Korea. In this study, we investigated the current state of pharmaceutical contamination and its associated ecological risks in streams near a pharmaceutical manufacturing complex. Methods: Seven pharmaceuticals (acetaminophen, clarithromycin, diclofenac, diphenhydramine, ibuprofen, mefenamic acid and roxithromycin) were measured in water samples collected from the streams near a pharmaceutical manufacturing complex. A predicted no-effect concentration (PNEC) was derived using either the assessment factor method or species sensitivity distribution method. In addition, a hazard quotient for each pharmaceutical was calculated by dividing its measured environmental concentration by its PNEC. Results: Samples collected downstream from the wastewater treatment plant (WWTP) had higher concentrations of pharmaceuticals than those collected from the reference site (upstream). Moreover, pharmaceutical concentrations were greater in ambient water than in the final effluent from the WWTP, which suggested that non-point sources were contributing to the contamination of the ambient water environment. Some of the target pharmaceuticals exhibited a hazard quotient >1, indicating that their potential ecological effects on the aquatic environment near the pharmaceutical industrial area should not be ignored. Conclusion: This study demonstrated that the pharmaceutical manufacturing area was contaminated with residual drugs, and that there was a possible non-point source near the WWTP effluent discharge area. The results of this study will aid in the development of management plans for pharmaceuticals, particularly in hotspots such as pharmaceutical industrial sites and their vicinities.

Effects of Rice Bran Extracts on Oxidative Stability of Corn Oil (옥수수유의 산화안정성에 대한 미강 추출물의 효과)

  • Yeon, Jeyeong;Lee, Seon Mi;Yang, Jinwoo;Kwak, Jieun;Kim, Youngwha;Jeong, Heon Sang;Lee, Junsoo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.10
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    • pp.1513-1517
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    • 2016
  • Rice bran contains high amounts of fiber and various phytochemicals, including vitamin E, ${\gamma}$-oryzanol, and phenolic acids. The oxidative stabilities of corn oil added with three rice bran extracts from two rice cultivars (Dasan 1 and Ilpum) were evaluated. The three rice bran extracts were unsaponifiable matter of rice bran (USM), methanolic extract of rice bran oil (MEO), and methanolic extract of defatted rice bran (MEDR). Each sample was stored at $50^{\circ}C$ for 24 days. Oxidation of these samples was determined every 3 days by measuring the peroxide value (POV) and conjugated diene value (CDV). Vitamin E content was analyzed on day 0 and day 24. The results show that the POV and CDV values of samples increased gradually during the storage period. The order of oxidative stability was shown as BHT> MEDR> MEO> USM> control, regardless of cultivars. In the case of vitamin E, ${\alpha}$-T, ${\gamma}$-T, ${\alpha}$-T3, and ${\gamma}$-T3 contents decreased by 89%, 31%, 83%, and 32% after storage for 24 days, respectively. In conclusion, MEDR showed higher oxidative stability and may have potential as a source of natural antioxidants in the oil industry.

A Study on the Safety Characterization Grounding Design of the Inner Photovoltaic System (태양광 발전단지 내부 그리드의 안전 특성화 접지 설계에 관한 연구)

  • Kim, Hong-Yong;Yoon, Suk-Ho
    • Journal of the Society of Disaster Information
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    • v.14 no.2
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    • pp.130-140
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    • 2018
  • Purpose: In this paper, we propose a design technique for the safety characterization grounding in the construction of the photovoltaic power generation complex which can be useful and useful as an alternative power energy source in our society. In other words, we will introduce the application of safety grounding for each application, which can improve and optimize the reliability of the internal grid from the cell module to the electric room in the photovoltaic power generation complex. Method: We analyze the earth resistivity of the soil in the solar power plant and use the computer program (CDEGS) to analyze the contact voltage and stratospheric voltage causing the electric shock, and propose the calculation and calculation method of the safety ground. In addition, we will discuss the importance of semi-permanent ground electrode selection in consideration of soil environment. Results: We could obtain the maximum and minimum value of ground resistivity for each of the three areas of the data measured by the Wenner 4 - electrode method. The measured data was substituted into the basic equation and calculated with a MATLAB computer program. That is, it can be determined that the thickness of the minimum resistance value is the most favorable soil environment for installing the ground electrode. Conclusion: Through this study, we propose a grounding system design method that can suppress the potential rise on the ground surface in the inner grid of solar power plant according to each case. However, the development of smart devices capable of accumulating big data and a monitoring system capable of real-time monitoring of seismic changes in earth resistances and grounding systems should be further studied.

Biological Activity of Extracts of the Starfish Asterias amurensis (아무르불가사리 추출물의 생리활성)

  • Go, Hye-Jin;Jo, Mi Jeong;Kim, Tae Young;Hong, Yong-Ki;Kim, Gun-Do;Lee, Byung-Woo;Park, Nam Gyu
    • Journal of Life Science
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    • v.24 no.5
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    • pp.491-497
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    • 2014
  • Nowadays, starfish is one of problems about interruption of marine ecosystem, so many researchers are focusing on application of the starfish (Asterias amurensis). In this study, we investigated the contractile and relaxant activity of the smooth muscles and the antimicrobial and antioxidant activity of six different tissues (muscle, gut, liver, tube feet, gonads, and body) of A. amurensis. Frozen samples were extracted with distilled water containing 1% acetic acid. Extracts from all the tissues, except the body tissue, showed potent antimicrobial activity against Escherichia coli D31. The dorsal retractor muscles (DRM) of muscle and gut extracts showed strong contraction responses. On the other hand, contractile activity on esophagus of squid Todarodes pacificus could be detected in all tissues tested. The contractile activity of the liver extract was higher than that of the other tissues. The body, tube feet, and liver extracts showed the contractile activity on the intestine of the panther puffer fish (Takifugu pardalis). Relaxation response on the DRM of starfish (A. pectinifera) was observed in all tissues tested. Increased antioxidant activity was observed in the gut, liver, and body extracts. The results suggest that the starfish (A. amurensis) is a potential source of novel bioactive compounds.

Antimicrobial and Antioxidant Effects of Functional Healthy Drinks from Some Medicinal Herbs and Coffee Mixture (약용식물과 커피 혼합물로부터 기능성 건강음료의 항균 및 항산화 효과)

  • Kim, In Hae;Kim, JinKyun;Lee, Jae Hwa
    • Journal of Life Science
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    • v.26 no.11
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    • pp.1225-1231
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    • 2016
  • In this study, our investigated the antioxidant activities and compared other bioassay including anti-microbial, antifungal activities and total polyphenol contents of functional healthy drinks from some medicinal herbs and coffee mixture. The kind of medicinal herbs, chaga mushroom (Inonatus obliqurs), moringa (Moringa Oleifera), gravila (Anona muricata), mulberry (Morus alba), Dioscoreaceae (Dioscorea quinquelaba), Berberidaceae (Epimedii Herba), Asteraceae (Artemisia capillaries) and siberian ginseng (Acanthopanax senticous,). The functional healthy drinks, named C1, C2, C3, C4, C5, C6 and C7 were summered in Table 1. The in vitro antimicrobial activity was examined against Gram positive bacteria, Gram negative bacteria and a fungus. The functional healthy drinks were broad spectrum of anti-microbial activity without antifungal activity against Candida albicans KCTC7965. In particularly, the C7 showed strong activity against Methicillin Resistant Staphylococcus aureus CCARM3089, CCARM 3115 and CCARM3561. And, the C7 showed 88% of free radical scavenging effect on 0.5 mg/ml using 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Functional healthy drink C7 was mulberry extracts from Morus alba, chaga mushroom from Inonatus obliqurs and moringa from Moringa olifera in additionally coffee extracts. Its results confirm that the potential use of mulberry extracts as a good source of antibacterial compounds or as a health promoting food and health drinks.

Prevalence of PERVs from Domestic Pigs in Korea (pol gene sequences) (국내 돼지에 존재하는 내인성 레트로 바이러스의 분포)

  • Kim, Y.B.;Yoo, J.Y.;Lee, J.Y.;Kim, G.W.;Park, H.Y.
    • Journal of Animal Science and Technology
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    • v.46 no.3
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    • pp.307-314
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    • 2004
  • Xenotransplantation of porcine organs has the potential to overcome the severe. shortage of human tissues and organs available for human transplantation. The swine represents an ideal source of such organs because of their plentiful supply and their numerous anatomical and physiological similarities to the human. However, this procedure also carries with a number of safety issues relating to the zoonotic infections. Porcine endogenous retrovinJses(PERVs), \Wich are germ line transmitted and persist without symptoms in the pigs, are most concerning zoonotic viroses. In order to analyze the prevalence of PERV in domestic pigs, four kinds of pigs'(Landrace, Berkshire, Yorkshire, and Duroc) genomic DNA were isolated from their hair follicles. PCR analysis was carried out for detection of PERVs using subgroup A/B/C and E pol sequence primers. All pigs (20 heads) tested had high copy number of PERVs within genomes. Subgroup A/B/C and E pol gene sequences from 20 isolates were determined by direct sequencing. Sequence analysis showed pol sequences are highly conserved among intra- and inter-subspecies(99.l and 98.8%, respectively). As a first report of PERV prevalence in Korea pigs, our data would be the basic concepts of PERV transmission study in xenotransplantation.

Nutritional Characteristics and Screening of Biological Activity of Cultured Wild Ginseng Roots (산삼 배양근의 영양성분 및 생리활성 탐색)

  • Park, Sung Jin;Yoo, Seon Mi;Kim, Young Eon
    • The Korean Journal of Food And Nutrition
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    • v.25 no.4
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    • pp.729-736
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    • 2012
  • The purpose of this study is to determine the possibility of using cultured wild ginseng roots as a natural health food source. To accomplish this purpose, the contents of general and antioxidative nutrients of cultured wild ginseng roots were measured. The contents of carbohydrate, crude protein, crude lipid and ash are 61.72%, 17.36%, 0.23% and 10.90%, respectively. Further, the calories of cultured wild ginseng roots were 323.97 kcal. Total dietary fiber was 82.13%. The protein contained a total of 18 different kinds of amino acids. The contents of amino acids were 16.15 g. The K was the largest mineral followed by P, Ca, and Mg, which means cultured wild ginseng roots is alkali material. The contents of saturated fatty acids and unsaturated fatty acids were 0.23 g, and 0.62 g, respectively. Crude saponine content was 25.87 mg/g. Total phenolic contents of cultured wild ginseng roots were 11.2mg/g, and total flavonoids contents were estimated as 4.2mg/g. The electron donating ability of cultured wild ginseng roots were 24.7~31.6%. The nitrite scavenging activity was pH dependent, and was highest at pH 1.2 and lowest at pH 6.0. The cultured wild ginseng roots extract showed the highest reducing power (0.06) at the concentration of $1,000{\mu}g/m{\ell}$. Based on the above results, we deemed that the cultured wild ginseng roots might have potential antioxdant activities.