• Title/Summary/Keyword: degree of contamination

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Opportunities for Joint Cooperation in R&D for FEALAC Countries: On Nanotechnology and Biotechnology

  • Trujillo, Ivan Montenegro;Jimenez, Edgar E Gonzalez;Ospina, Monica Botero
    • STI Policy Review
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    • v.7 no.2
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    • pp.106-131
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    • 2016
  • The general purpose of this paper is to identify opportunities for and to measure existing collaboration on research and development between institutions from the countries of Asia and Latin America in FEALAC's framework, in the fields of biotechnology and nanotechnology and their convergence. The methodological approach includes scientific and technological surveillance and research seeking to identify both the R&D and innovation capacities of the countries as well as the degree of international cooperation between countries of the two regions; case studies and a study of the governance framework of international collaboration in R&D about issues considered global challenges. The study has three main findings. First, nanotechnology, biotechnology and their convergence contribute to solving the problem of contamination by heavy metals affecting most of the countries that are part of FEALAC and to address problems arising from the accelerated rate of energy consumption, which also contributes to environmental damage. In this scenario, important business opportunities arise from the adaptation and development of bio-refinery technologies. Second, the scientific relationship between FEALAC countries, mainly between Asian and Latin American countries, is weak as can be seen in research for articles and patents. But there is plenty of room and potential for improvement. Third, current and upcoming joint R&D programs and projects should be linked both to existing governance structures and to new ones that serve as experiments of STI public policy regarding innovative management of intellectual property and capacity building. Practical implications are included in lessons learned and a set of recommendations involving a couple of proposals. One proposal calls for research and innovation in promising fields for international cooperation. Another proposal creates mechanisms in the governance framework for sharing knowledge, capacity building, and funding.

A study on the color controlled of painter's work (페인트 도장공사의 색관리에 관한 연구)

  • Shim, Myung-Sup;Lee, Hyun-Jeong
    • Journal of the Korea Institute of Building Construction
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    • v.3 no.1
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    • pp.107-114
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    • 2003
  • This study aims to find methods that prevents aging of buildings paint coating and that limits defects in construction. Defects in painting can occur in four stages: pure paint, during painting, after the paint coating has dried, and after some period of time has passed after coating. Paint may become bad due to precipitation of pigments, formation of membranes, and seeding during manufacturing. Therefore, it is important that the paint is well mixed and kept airtight at a cool, dark place. Indents, paint brush strokes, orange peel, separation of colors, and paint running and spreading during the paint work process can be prevented by using high quality materials and applying a high-level of construction method. After the paint coating has dried, boiling, yellowing, poor drying, poor bonding, and/or glen deficiency may occur. These are influenced by the levels of cleanness of the dried product, drying temperature and hydration. Then, when the coating has been left dried for some period of time, cracking, peeling, scaling, swelling, discoloring, and/or rusting may develop due to the ultraviolet and contaminants in the air. Since these defects occur due to inappropriate construction schedule and/or hot and humid condition, one must use weatherproof materials. Furthermore, poor paint color may be caused by contamination in the sample plate, discoloration, and/or discrepancies in colors which are due to material differences, level of glossiness, degree of dispersion, dual color property of metallic colors, precipitation of pigments, etc. One should achieve reduction in construction cost and effectiveness in paint work by limiting contaminations in the construction site and strictly observing to construction regulations.

Evaluation of Washing Method for Sterilization of Gel Container for Ultrasound Inspection (초음파검사용 젤 용기의 제균을 위한 세척방법 평가)

  • Lee, Hee-Jeong;Lee, Suk-Jun;Seoung, Youl-Hun
    • Journal of radiological science and technology
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    • v.41 no.3
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    • pp.241-247
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    • 2018
  • The purpose of this study was to compare the ultrasound gel container washing methods for the sterilization of contaminants and to find the useful methods for the prevention of infection caused by the ultrasonic gel containers. In this experiment, a 250 mL ultrasonic gel container was used, and the ultrasonic gel used was a non-sterile gel (ECO GEL 99, SeungWon Medical, Korea). In order to evaluate the degree of contamination, new 250 mL 15 containers were divided into 5 groups to perform five types of washing by no treatment, washing with water, washing with soap, washing with bottle cleaner and high disinfection level washing. After the washing process, filled the gel container with gel and after 2 weeks, the number of colonies in the gel container was sampled repeatedly twice in the same ultrasonic laboratory and compared before and after washing. As a result of among the five cleaning methods used in this study, 87.2% and 88.9% of the soapy water washing (p = 0.028) and high level washing (p = 0.027) showed significant bacterial reduction rates, respectively. Our findings conclusively an ultrasonic gel container cleaning method for removing contaminants has been found to be an effective sterilization method at a low cost with a soapy water cleaning method. Therefore, it is expected that it will be helpful to prevent the infection caused by the ultrasonic gel container by suggesting the sterilization cleaning method that is practically useful in this study.

Inactivation of Vibrio parahaemolyticus by Aqueous Ozone

  • Feng, Lifang;Zhang, Kuo;Gao, Mengsha;Shi, Chunwei;Ge, Caiyun;Qu, Daofeng;Zhu, Junli;Shi, Yugang;Han, Jianzhong
    • Journal of Microbiology and Biotechnology
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    • v.28 no.8
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    • pp.1233-1246
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    • 2018
  • Vibrio parahaemolyticus contamination causes serious foodborne illness and has become a global health problem. As a disinfectant, aqueous ozone can effectively kill a number of bacteria, viruses, parasites, and other microorganisms. In this study, three factors, namely, the aqueous ozone concentration, the exposure time, and the bacterial density, were analyzed by response surface methodology, and the aqueous ozone concentration was the most influential factor in the sterilization ratio. Under low aqueous ozone concentrations (less than 0.125 mg/l), the bacterial cell membranes remained intact, and the ozone was detoxified by intracellular antioxidant enzymes (e.g., superoxide dismutase and catalase). Under high aqueous ozone concentrations (more than 1 mg/l), cell membranes were damaged by the degree of peripheral electronegativity at the cell surface and the concentration of lactate dehydrogenase released into the extracellular space, and the ultrastructures of the cells were confirmed by transmission electron microscopy. Aqueous ozone penetrated the cells through leaking membranes, inactivated the enzymes, inhibited almost all the genes, and degraded the genetic materials of gDNA and total RNA, which eventually led to cell death.

Distribution and Effect on Organisms of Butyltin Compounds Inside Songsan Harbor of Cheju Island (제주도 성산항내 부틸주석화합물의 분포와 생물체에 미치는 영향)

  • 김상규;안이선;고병철;조은일;이기호
    • Journal of Environmental Science International
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    • v.9 no.4
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    • pp.285-294
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    • 2000
  • Butyltin compounds (BTs) in seawater, sediments and organisms (Thais clavigera, Liolophura japonica and Cellana nigrolineata), were quantitatively determined to evaluate their distribution inside Songsan Harbor of Cheju Island. In addition, imposex in T. clavigera was used to assess the effect on organisms of BTs. Analysis of the samples collected in seawater, sediments (March, June and August) and organisms (May, July and August) in 1998, confirmed the contamination of BTs in the aquatic environment inside Songsan Harbor. The main BTs species in seawater and sediments was monobutyltin (MBT), tributyltin (TBT), respectively, irrespective of survey time. In oranisms, TBT and dibutyltin (DBT) were detected in similar concentrations for T. clavigera and L. japonica, but for C nigrolineata, DBt concentration was the highest. TBT, the most toxic to aquatic organisms among BTs, was found at concentrations which were sufficient to have a serious effect on the sensitive organisms upon chronic exposure, The relatively high correlations (r>0.83) between BTs indicated that DBT and MBT were mainly degraded from TBT based on antifouling paint and their sources were negligible. The sedimentary organic matters did not have influence on the distribution of BTs in marine environment, and lipid content in T. clavigera did not show a correlation with TBT concentrations. The rate of occurrence of imposex in T. clavigera was 100%, and the relative penis length index (RPLI) and the relative penis size index (RPSI) which represent the degree of imposex were 79.7%, 58.1%, respectively. Measurement of imposex in T. clavigera was expected to be a very helpful tool for preliminary survey of BTs prior to trace analysis of BTs.

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Characteristics of Particulate Matter Concentration and Classification of Contamination Patterns in the Seoul Metropolitan Subway Tunnels (서울시 지하철 터널 내 입자상물질의 농도 특성 및 오염형태 분류)

  • Lee, Eun-Sun;Lee, Tae-Jung;Park, Min-Bin;Park, Duck-Shin;Kim, Dong-Sool
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.6
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    • pp.593-604
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    • 2017
  • The suspended particulate matter(PM) was measured in subway tunnel of Seoul Line 1 to 9 in order to evaluate the pollution degree and characteristics of the PM in the subway tunnel. Also, to analyze the effect of outdoor aerosol concentration on the PM concentration of subway tunnels, the ambient PM concentration around the subway station was extracted by spatial analysis using $PM_{10}$ data of Seoul air pollution monitoring network. Finally, in order to understand pollution pattern in the Seoul subway tunnels, cluster analysis was performed based on input data set such as PM levels in tunnel, tunnel depth, length, curvature radius, outdoor ambient air pollution levels and so on. The average concentration of $PM_{10}$, $PM_{2.5}$, and $PM_1$ on subway tunnels were $98.0{\pm}37.4$, $78.4{\pm}28.7$, and $56.9{\pm}19.2{\mu}g/m^3$, respectively. As a result of the cluster analysis, tunnels from Seoul subway Line-1 to Line-9 were classified into five classes, and the concentrations and physical properties of the tunnels were compared. This study can provide a method to reduce PM concentration in tunnel for each pollution pattern and provide basic information about air quality control in Seoul subway tunnel.

Heavy Metal Contamination of Soils and Crop Plants in the Yugu-Kwangcheon Au-Ag Metallogenic Province (유구(維鳩)-광천(廣川) 금은광화대지역(金銀鑛化帶地域)에서의 토양(土壤) 및 농작물(農作物)의 중금속오염(重金屬汚染))

  • Kim, Kyoung-Woong;Paik, Sung-Hee;Lee, Hyun Koo
    • Economic and Environmental Geology
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    • v.28 no.4
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    • pp.389-394
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    • 1995
  • Yugu-Kwangcheon Au-Ag Province is connected to the southwestern part of the Cheonan Province and includes the Gubong (one of the biggest gold mine in past), Daebong and Samgwang mines. Cadmium concentrations in sphalerite of Yugu-Kwancheon Province is higher than those of other Au-Ag provinces and could be the source of the heavy metal contaminations. Heavy metals are present in rock-soil-plant-human system from natural geological materials, and dietary intake through this system makes a significant contribution to the ingestion of heavy metals by man. In order to examine the degree and extent of heavy metal contaminations in the Gubong, Daebong and Samgwang mine areas of Yugu-Kwangcheon Province, soil, stream water, sediment and crop plant samples were taken and analyzed for Cd, Cu, Pb and Zn by Atomic Absorption Spectrometry (AAS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Cadmium and Pb concentrations in paddy/farm soils and stream sediments from the Gubong and Samgwang mine areas are higher than those in uncontaminated soils. Lead concentrations in crop plants cultivated in these soils are high up to $0.38{\mu}g/g$ in rice grain and $4.5{\mu}g/g$ in sesame. In these mine areas, regular consumption of crop plants by the local population would seem to pose a potential health problems from long-term Pb exposure. The biological absorption coefficient in rice grain for heavy metals varies in the order $C_d=Zn>Cu>Pb$ and the relationship between Cd concentrations in soils and crop plants is expressed by the equation $Cd_{plant}=0.11245\;Log\;Cd_{soil}+0.13472$.

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Comparison of Water Quality Between Private and Simple-Piped Drinking Water Supply in Rural Community (농촌지역 개인소유 음용수와 간이상수도의 수질에 대한 비교 연구)

  • 이진헌;이인숙
    • Journal of Environmental Health Sciences
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    • v.20 no.1
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    • pp.54-61
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    • 1994
  • This study was carried out to investigate the degree of contamination in private-drinking water supply (PDWS) and simple-piped water supply (SPWS), and to compare of water quality between them for 3 years from 1990 to 1992. The results of the study were as follows: 1. Private-drinking water supply (PDWS) (1) Field-Site (ㄱ) The items which were very significantly over the criteria (p<0.01), were temp., pH, NO-N, standard plate count (S.P.C.) and Coliform. (ㄴ) No. of households which were over the criteria, were 11.2~51.7% in temp., pH, NH$_3$-N and NO$_2$-N, and 83.1~93.3% in NO-N, S.P.C. and Coliform. (2) Moutain-Site (ㄱ) The items which were over the criteria, were NO$_2$-N (p<0.05), S.P.C. (p<0.01) and Coliform (p<0.01). (ㄴ) No. of households which were over the criteria, were 33.6 ~ 75.6% in NO$_2$-N, S.P.C. and Coliform. (3) No. of households which were fit to the criteria of all items, were 9.0% in field-site and 14.1% in mountain-site. 2. Simple-piped water supply (SPWS) (1) The items which were very significantly over the critera (p<0.01), were standard plate count (S.P.C.) and Coliform. (2) The water qualities of adjacent and remote samples were better than those of source samples. (3) Residual chloride was not detected in any sample. In conclusion, rural community requires to be continually performed the policy of safety drinking water supply, and to be devised an epoch-making counterplan for the level-up of simple-piped water supply (SPWS), espically on the method of disinfection.

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The Study of Natural Background of Geologic Units for Stream Sediments in the Gurye Area (구례지역 하상퇴적물의 지질집단별 자연배경치에 대한 연구)

  • 박영석;장우석;김종균
    • Economic and Environmental Geology
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    • v.36 no.4
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    • pp.275-284
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    • 2003
  • We collected the samples of stream sediments from primary channels in order to establish natural background of major and minor elements for geologic units in the Gurye area. Stream sediments samples having no possibility of contamination effect and representing drainage basins composed of uniform geology, were collected from April to May in 1999, the chemical analysis of which was carried out. The tolerable level was used to investigate the enrichment degree of harmful elements. The contents of Ni and Cr exceeded the tolerance level in some sections. The tolerance level excess of those elements was regarded as the effect of the metamorphic rock which constituted the bed rock of the area. In order to identify the comprehensive enrichment pattern, the tolerable level was used in calculating the enrichment index. The enrichment index of harmful heavy metals showed that Granite gneiss area is 0.39, Porphyroblastic granite gneiss area 0.32, Biotite gneiss area 0.42, Migmatitic gneiss area 0.41, Tuff area 0.30, Andesite area 0.46, Conglomerate area 0.42, and Granite area 0.26. Those results showed that natural background of Gurye area had not been exposed to harmful heavy metal elements.

Evaluation of the Effect of the Discharged Water from Bong Stream after Rainfall Events on the Bacteriological Water Quality in Gangjinman, Korea (강우 발생에 따른 남해군 봉천 방출수가 강진만 해역의 세균학적 수질에 미치는 영향 평가)

  • Park, Kun-Ba-Wui;Jo, Mi-Ra;Lee, Hee-Jung;Kwon, Ji-Young;Son, Kwang-Tae;Lee, Tae-Seek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.6
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    • pp.622-629
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    • 2011
  • We investigated the effect of the discharged water from Bong Stream, which is located in the drainage area of Gangjinman area on the bacteriological water quality in the coastal area after rainfall events. Following 12.5 mm of rainfall, water discharged from Bong Stream had a very limited effect on bacteriological water quality in adjacent area and the affected area did not extend to the designated area. On the other hand, after 23 mm rainfall, the density of fecal coliform at stations located in the designated area was higher than at stations located in the adjacent area. The degree of bacteriological contamination at the surveyed stations in the coastal area after rainfall events did not show a relationship with distance from the shoreline. These results indicate that the direction of spread and the range of contaminants from the drainage area were affected by tides at the time of the survey. Therefore, a detailed survey of the effects of tides on the diffusion characteristics of the contaminants from Bong Stream is needed to establish a proper management plan for the surveyed area.