• Title/Summary/Keyword: Contamination

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Effects of Saliva Contamination on Shear Bond Strength with Conventional, Moisture Insensitive, and Self-Etching Primers (Moisture Insensitive Primer와 Self-Etching Primer를 사용한 교정용 브라켓 접착 시 타액오염이 전단결합강도에 미치는 영향 비교)

  • Oh, Yoonjeong;Oh, Sohee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.46 no.1
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    • pp.21-28
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    • 2019

  • The aim of this study was to compare the shear bond strengths of orthodontic bracket with Conventional primer (CP), Moisture insensitive primer (MIP), and Self-etching primer (SEP). In addition, the effect and the timing of saliva contamination on shear bond strength was evaluated. A total of 135 bovine mandibular incisors were used in the study and divided into 3 groups. Group I, II and III were used CP, MIP, SEP, respectively. Each group was then divided into three subgroups: the group without saliva contamination, the group with primer application after saliva contamination, and the group with saliva contamination after primer application. After the primer application, the metal bracket for the lower incisor was attached and the shear bond strength was measured. The mean shear bond strengths was highest with CP and lowest with SEP in dry condition. However, CP showed a significant decrease in shear bond strength in the presence of saliva contamination. MIP and SEP showed no significant decrease in shear bond strength with saliva contamination.

  • https://doi.org/10.5933/JKAPD.2019.46.1.21 인용 PDF KSCI

Suggestion for Legal Definitions of Keywords on Soil Contamination Policies in Korea (토양환경보전법의 토양오염 관련 주요 용어의 정의 및 재정립에 관한 고찰)

  • Park, Yong-Ha;Yang, Jae-E.
    • Journal of Environmental Policy
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    • v.4 no.1
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    • pp.39-67
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    • 2005

  • In order to properly define the terms such as soil, soil contamination, soil contamination site and remediation, which are the key terms under the Soil Environment Conservation Act(SECA) in Korea, we analyzed the legal definitions of the similar key words in legislations of the developed western countries. The selected countries were the United States of America, the United Kingdom, the Netherlands, Germany, and Denmark. The legal definitions of these keywords were very much diversified due to different levels of soil contamination, as well as different industrial, social, and legal backgrounds in each country. However, fair suggestions for definitions of the key terms in SECA were derived from the comparative analyses of these countries. First and foremost, SECA should provide a definition of 'soil' which includes a concept of the natural soil layer produced from soil mineralization processes. Groundwater and sublayer of the groundwater would. be excluded in the boundary of the soil with regards to the Groundwater Act of Korea. Definition of 'soil contamination' of SECA should include a concept of risk assessment(soil contaminants, pathway, and receptors), purpose of land use, and the acquired limitation levels of soil contaminants. Soil contamination activity either industrial or anthropogenic in SECA article2-1, could be substituted for a concept of soil risk assessment. Definition of 'soil contamination site' could derive from amalgamating the concepts of i) soil contamination in conjunction with contaminants, ii) risk assessment, iii) a concept of land use, and iv) knowing limitation of contamination site designation. Definition of 'remediation of contaminated site' should include the objective, intention, action, methodology and limit of the remediation. These suggested definitions would increase the efficacy of soil environment conservation policies, which includes the survey of the potentially contaminated area, remediation, and removal of the site.

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Advances in Enhancing Nutrient Utilization for Ruminants by Nutritional Manipulation to Reduce Environmental Contamination - Review -

  • Lu, De-xun
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.3
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    • pp.395-401
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    • 2001

  • A review of present understanding of the dietary nutrient utilization in ruminant animals is presented. For increasing the utilization of dietary nutrients and reducing environmental contamination, highlighting the development and use of nutritional manipulation technique is suggested.

  • https://doi.org/10.5713/ajas.2001.395 인용 PDF

Groundwater Contamination (지하수 오염)

  • Jeon, Hyo-Taek
    • 수도
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    • v.25 no.1 s.88
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    • pp.25-35
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    • 1998

  • Factors controlling water quality, water-quality standards, and normal ranges of concentrations in unpolluted fresh water and the sources of elements were explained in this paper. In particular, the sources of groundwater contamination such as the disposal of domestic waste water, landfills, chemical spills and leaking underground tanks, and agricultural and mining activities were discussed.

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