• Title/Summary/Keyword: reducible

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Trace Metal Contamination and Solid Phase Partitioning of Metals in National Roadside Sediments Within the Watershed of Hoidong Reservoir in Pusan City (부산시 회동저수지 집수분지 내 국도도로변 퇴적물의 미량원소 오염 및 존재형태)

  • Lee Pyeong-Koo;Kang Min-Joo;Youm Seung-Jun;Lee In-Gyeong;Park Sung-Won;Lee Wook-Jong
    • Journal of Soil and Groundwater Environment
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    • v.11 no.5
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    • pp.20-34
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    • 2006
  • This study was undertaken to assess the anthropogenic impact on trace metal concentrations (Zn, Cu, Pb, Cr, Ni, and Cd) of roadside sediments (N = 70) from No.7 national road within the watershed of Hoidong Reservoir in Pusan City and to estimate the potential mobility of selected metals using sequential extraction. We generally found high concentrations of metals, especially Zn, Cu and Pb, affected by anthropogenic inputs. Compared to the trace metal concentrations of uncontaminated stream sediments, arithmetic mean concentrations of roadside sediments were about 7 times higher for Cu, 4 times higher for Zn, 3 times higher for Pb and Cr and, 2 times higher for Ni and As. Speciation data on the basis of sequential extraction indicate that most of the trace metals considered do not occur in significant quantities in the exchangeable fraction, except for Cd and Ni whose exchangeable fractions are appreciable (average 29.3 and 25.8%, respectively). Other metals such as Zn (51.4%) and Pb (45.2%) are preferentially bound to the reducible fraction, and therefore they can be potentially released by a pH decrease and/or redox change. Copper is mainly found in the organic fraction, while Cd is highest in the exchangeable fraction, and Cr and Ni in the residual fraction. Considering the proportion of metals bound to the exchangeable and carbonate fractions, the comparative mobility of metals probably decreases in the order of Cd>Ni>Pb>Zn>Cr>Cu. Although the total concentration data showed that Zn was typically present in potentially harmful concentration levels, the data on metal partitioning indicated that Cd, Ni and Pb pose the highest potential hazard for runoff water. As potential changes of redox state and pH may remobilize the metals bound to carbonates, amorphous oxides, and/or organic matter, and may release and flush them through drain networks into the watershed of Hoidong Reservoir, careful monitoring of environmental conditions appears to be very important.

The Paradox of Grant Allen's Physiological Reductionism (그랜트 알렌의 생리학적 환원주의의 역설)

  • Lee, Sungbum
    • Cross-Cultural Studies
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    • v.44
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    • pp.411-430
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    • 2016
  • One of central issues in the Literature and Science discourses during the Victorian era is the relation of physiology to psychology. Many thinkers tackle the question of whether or not psychic phenomena can be reducible to their physiological bases. For instance, Victorian physiologist William Benjamin Carpenter claims that there should be a boundary between physiological and psychological qualities. Yet, his contemporary writer Grant Allen contends for the reduction of psychology into physiology. In the essay, I discuss Grant Allen's work Physiological Aesthetics (1877) so as to eventually problematize his physiological reductionism. I especially highlight the paradox of his physiological aesthetics. In order to clarify my argument, I introduce two concepts: evolutionary aesthetics and physiological reductionism. On the one hand, Allen argues for the development of aesthetic appreciation. The gradual evolution from gaudy to serene colors, for instance, reflects the fine differentiation of sensory organs. He believes that the existence of varied aesthetic pleasures corresponds to the evolution of sensory nerve structures. Nonetheless, Allen ironically gives more weight to the commonality of aesthetic experiences than to this teleological ordering of aesthetic experiences. He argues that there is no fundamental difference among humans in terms of their aesthetic assessments. Furthermore, there is even no essential distinction among plants, animals, and humans in light of their aesthetic appraisals, he states firmly. Although he asserts the gradual advance of aesthetic feelings caused by the intricacy of nervous systems, he simultaneously trivializes the evolution of aesthetic appraisal. In the essay, I highlight this paradox in Allen's physiological aesthetics. It should be underscored, lamentably enough, that Allen seeks biological purity by erasing fine lines among physiology, psychology, and sociality. He estranges aesthetic experiences from subjective variations and their socio-cultural contexts. He makes great efforts to eliminate individual differences and socio-cultural specificities in order to extremely biologize aesthetic experiences. Hence, Allen's physiological aesthetics is marked as the politics of physiological purification.

A Study on the Understanding Method and Methodology of Character Education: A Transition to Character Education based on a Correct Understanding and Attitude towards Human Nature and Emotions (인성교육 이해방식과 방법론에 관한 일고찰 - 인간 본성과 감정의 올바른 이해를 토대로 한 인성교육으로의 전환 -)

  • Kim Sung-sil
    • Journal of the Daesoon Academy of Sciences
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    • v.42
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    • pp.201-226
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    • 2022
  • Character education begins with a clear definition of character. There are claims that humanity is reducible to human nature or personality, but when approached from an educational perspective, human nature soon boils down to the question of its ultimate goodness or wickedness. There is a significant difference between the educational systems that emerge from the standpoint that human nature is evil versus the standpoint that human nature is good. With regards to educational outcomes, this can be observed both in terms of human nature and personality. Modern education today sees education as leading the immature to a mature state from the standpoint that human nature is evil. But if human nature is evil, how could we implement an education that would render it good? If character education becomes a system of etiquette education or one of instilling manners whereby simple wrong cases are righted, it would be nothing but a follow-up to the wrong educational cases that had been carried out previously. In that sense, character education is correction; not education. Education should be done in a way that realizes and understands the perfect self rather than unfolding as a process of constantly correcting and reinforcing immature human beings. In that sense, this paper posits that enabling students to understand their own emotions would serve as a correct form of character education. This would be a system of focusing on emotions that reveal the goodness of human nature. Personality can be educated, but education at this time should be a way to bring out a student's already good and even perfected nature. This is more realistic than replacing a 'faulty' character with a good character which supposedly did not exist previously. If personality education morphs into 'emotional self-understanding,' contemplations on 'why not to do' unsavory acts rather than mere negative commands 'don't do that,' and listening to what one's emotions intuit prior to and after given actions, then that would arise to the true standard of a good education.

A Study on the Physico-Chemical Characteristics of Acid Sulfate Soil in Kimhae Plain (김해평야(金海平野)에 분포(分布)된 특이산성토(特異酸性土)(답)(沓)의 이화학적성질(理化學的性質)에 관(關)한 조사연구(調査硏究))

  • Park, N.J.;Park, Y.S.
    • Korean Journal of Soil Science and Fertilizer
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    • v.2 no.1
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    • pp.15-26
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    • 1969
  • The study on physico-chemical characteristics of the acid sulfate soil present in Kimhae plain was carried out with 28 surface and subsoils from lower and higher produtive area and two representative profile samples from the areas reclaimed a few decades ago and around 10 years ago respectively. 1. There are no differences in soil texture between lower and higher productive soils being mostly silty clay loam and silty clay. 2. Very significant differences in pH, degree of base saturation and extractable aluminium content are observed; lower pH, lower degree of base saturation and higher aluminium in the lower productive soils and subsoils. The pH and degree of base saturation of these soils are extremely low whereas aluminium content is very high compared to ordinary paddy soil. 3. Cation exchange capacity of these soils are slightly higher than ordinary paddy soils. In higher productive soils, exchangeable calcium and magnesium are of same order, whereas in lower productive soils magnesium content is appreciably higher than calcium. 4. Though the soil is derived from marine and estuarine sediment, the soluble salt content is not high. There are only few lower productive surface soils and subsoils having Ec values of the saturation extracts higher than 4 mmhos but lower than 9 mmhos/cm. 5. Organic matter content of these soils is a bit higher compared to ordinary paddy soils, but, nitrogen content is comparatively low. C/N ratio of these soils is around 12. 6. Sulfur content is considerably higher but oxidizable sulfur is found to be very low. Total sulfur is generally high in subsoils and lower productive soils. 7. Active iron and available silica are slightly higher than ordinary paddy soils but easily reducible manganese is very low. Almost no differences are also observed between lower and higher productive soils. 8. Available phosphorus content is extremely low in particular, regardless of higher or lower productive soils. 9. The two representative profiles from the area of earlier reclamation and recent one show that samples from earlier reclaimed area contain less amount of free acids, sulfur compounds, toxic aluminium and soluble salts etc. than the other. This indicate greater leaching and possible addition of lime for a longer period of time. 10. From the results obtained, it can be concluded the higher productivity of group I soils is due to the greater leaching and neutralisation of acidity by liming materials, It can also be concluded that the productivity of both types can be increased by addition of liming materials and improvement of drainage facilities.

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