• 제목/요약/키워드: secondary science

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산림탄소상쇄 사업에 따른 이차적 배출량 산정에 관한 연구 (Estimation of Secondary Emissions from Forest Carbon Offset Projects)

  • 김영환
    • 한국기후변화학회지
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    • 제6권4호
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    • pp.257-265
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    • 2015
  • For estimating a net removal of carbon dioxides from a forest carbon offset project, it is necessary to consider secondary emissions occurred from the use of machineries or vehicles. According to the forest carbon standard in Korea, a default rate (5%) could be applied for estimating secondary emissions of small projects, which provide annual net removals less than or equal to $600tCO_2$, while secondary emissions should be estimated for larger projects with field survey. In this study, we intended to develop a methodology for estimating the secondary emission of a forest carbon project. For this purpose, we analyzed the working process and the carbon emissions of the forest management activities for major tree species in Korea. Based on the developed methodology, we estimated the secondary carbon emission of a reforestation project. The result showed that the secondary carbon emission of a reforestation project was estimated between 0.42% and 1.19 % compared to net removals, that is to say that the current default rate in the forest carbon standard could give an overestimated secondary emission.

초 . 중등학교 과학 실험수업의 유형 분석 (Analysis of the Types of Laboratory Instruction in Elementary and Secondary Schools Science)

  • 양일호;김석민;조현준
    • 한국과학교육학회지
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    • 제27권3호
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    • pp.235-241
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    • 2007
  • 이 연구는 실험수업 유형 분류틀을 사용하여 초 중등학교에서 실시되고 있는 주요 실험수업의 유형들을 확인하는 것이다. 이 연구를 위해 사용된 실험수업 유형 분류틀의 타당도는 4.23이다. 이 연구를 위해, 초등학교에서 100차시, 중등학교에서 30차시의 실험수업이 분석대상으로 수집되었다. 실험수업들의 유형을 분석결과, 분석자간 일치도는 0.91이었다. 분석 결과, 초등학교에서는 발견실험수업과 확인실험수업이 주요 수업 유형임이, 중등학교에서는 확인실험수업과 발견실험수업이 주요 수업유형으로 확인되었다. 초등학교와 중등학교에서 대부분 실험절차가 교사나 활동지를 통해 학생들에게 주어지고 있었다. 실험의 접근방식은 초등에서는 귀납적인 형태가 많았고, 중등에서는 연역적인 형태가 많았다.

초중등 과학교사들의 과학연구윤리교육에 대한 인식 (The Perceptions of Science Teachers Regarding Science Research Ethics Education)

  • 김성덕;김효남
    • 한국초등과학교육학회지:초등과학교육
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    • 제32권4호
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    • pp.393-403
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    • 2013
  • The purpose of this study was to investigate the perception of school teachers in science research ethics and perception of science research ethics education. A survey was administered for this study and a total 167 elementary and secondary teachers studying in K University graduate school participated. The survey was organized to examine participants' 1) science research ethics awareness, 2) status of science research ethics education, and 3) needs for science research ethics education, and 4) the perception of the direction of the science research ethics education in school. Each item was responded using either 1 to 5 Likert type scale, multiple choices questionnaires. The results were as follows: both of elementary and secondary school teachers showed above average interest in science research ethics and secondary school teachers showed significantly higher interest than elementary school teachers(p<0.05). In degree of awareness of science research ethics, plagiarism (M=3.98) was the highest, followed by free-riding(M=3.78), the scientist's social responsibility(M=3.71), and forge(M=3.61). In response science research ethics problem occurs in science education activities more than the average(M=3.39). Teacher's response on the teaching of science research ethics ranges from 3.02 to 4.47, but each science research ethics elements was showed a large deviation. Elementary and secondary school teachers responded that science research ethics education needed(M=4.34). Science research ethics education should be included in the school curriculum. Eighty-five percent of the teachers responded that the science research ethics education should be started from elementary school. 'Discussion-type classes with examples' was preferred as an effective teaching. And teachers needed 'instructional materials' and 'teachers training' for science research ethics education.

Effects of Tungsten on the Precipitation Kinetics of Secondary Phases and the Associated Susceptibility to Pitting Corrosion in Duplex Stainless Steels

  • Park, Chan-Jin;Kwon, Hyuk-Sang
    • Corrosion Science and Technology
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    • 제5권6호
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    • pp.189-195
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    • 2006
  • Effects of tungsten (W) on the precipitation kinetics of secondary phases and the associated resistance to pitting corrosion of 25%Cr duplex stainless steels were investigated through microstructural and electrochemical noise analyses. With the partial substitution of W for Mo in duplex stainless steel, the potential and current noises of the alloy were significantly decreased in chloride solution due to retardation of the ${\sigma}$ phase precipitation. The preferential precipitation of the $\chi$ phase in the W-containing alloy during the early period of aging contributed to retarding the precipitation of the $\sigma$ phase by depleting W and Mo along grain boundaries. In addition, the retardation of the nucleation and growth of the $\sigma$ phase in the W-containing alloy appears to be attributed to the inherently low diffusivity of W compared with that of Mo.

A Review on Venom Enzymes Neutralizing Ability of Secondary Metabolites from Medicinal Plants

  • Singh, Pushpendra;Yasir, Mohammad;Hazarika, Risha;Sugunan, Sunisha;Shrivastava, Rahul
    • 대한약침학회지
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    • 제20권3호
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    • pp.173-178
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    • 2017
  • Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science) and articles of peer-reviewed journals. Results:Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5'nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.

Clues to Understand the Regulatory Metabolisms Governing the Biosynthesis of Fungal Secondary Metabolites

  • Choi, Yoon-E
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2015년도 춘계학술대회 및 임시총회
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    • pp.14-14
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    • 2015
  • Fungi are of particular interest due to their capacity to produce an extensive array of secondary metabolites. While many secondary metabolites have no known functions to the producing fungal organisms, these metabolites have tremendous importance to humans with beneficial (e.g., antibiotics) or detrimental (e.g., mycotoxins) properties. In this study, two important filamentous fungi, Fusarium verticillioides and Mycosphaerella graminicola were selected as target species and the genes regulatory functions on the biosynthesis of secondary metabolisms were studied. Functional genomics including forward and reverse genetics, and proteomics were utilized to better understand the complex secondary metabolism regulations in both F. verticillioides and M. graminicola. Identified genes in either F. verticillioides or M. graminicola background were CPP1 (a putative protein phosphatase gene), GAC1 (encoding a GTPase activating protein), MCC1(encoding c-type cyclin), and the velvet gene, MVE1. Our data suggest that there are diverse regulatory genes on fungal secondary metabolites with distinct or overlapping functional roles.

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