• Title/Summary/Keyword: enrichment period

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Geochemical Characteristics and Pollution Level of Heavy Metals of Asian Dust in Daejeon Area, 2007 (spring season) (2007년 봄철 대전지역에서 발생한 황사 및 대기부유물의 지구화학적 특성 및 중 금속의 오염도)

  • Lee, Pyeong-Koo;Youm, Seung-Jun;Bae, Beob-Geun
    • Economic and Environmental Geology
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    • v.45 no.3
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    • pp.217-235
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    • 2012
  • We evaluated the geochemical characteristics and their potential pollution of Asian Dusts in Daejeon, Korea during spring 2007. Compared with the chemical compositions of soils in source area of Asian Dust, those of aerosols in Daejeon were enriched with trace elements (ten to hundred fold), inferring that pollutants from China have affected on local environment in adjoining country such as Korea. Chemical analysis of aerosols during Asian dust showed that fine particles ($PM_{2.5}$) contained high contents of trace elements such as Cr, Cu, Pb, Zn, V, S, As, Cd, Co, Ni, Mo, Sb, Cs, Rb, Th, Sc and Y. In the case of TSP (Total Suspended Particle), Zr, Sr, Ba, Li, Th and U were contained much more than other trace elements. The contents of some elements (i.e. Li, Cs, Co, U, Cr, Ni, Rb, V, Th, Y, Sr and Sc) in aerosols collected in Asian Dust period, which are not likely enriched by air pollutants, were higher (2 - 4.2 fold) than those in Non Asian Dust period, indicating that these elements could be used as indicator elements for determining the occurrence of Asian Dust phenomena (especially, Sr, V, Cr & Li). In the case of Asian Dust coming through the big cities and/or industrial areas of China, the domestic aerosols had higher contents of trace elements (such as S, Cd, Zn, Pb, Cu, Mo and As) than those from Northeastern China via North Korea, indicating that the transportation courses of air mass are very important to determine the pollution degrees. Using the enrichment factors of trace elements in aerosols during Asian Dust and Non Asian Dust, we identified that some elements (i.e. S, Zn, Cu, Pb, As, Mo and Cd) were most problematic in terms of environmental hazard aspects, and these elements could affect adverse effects on human health as well as ecosystem and surface environment (soil and water) through long-lived precipitation.

Academic Enrichment from The Great Learning(大學) to The Essentials of Sagely Learning(聖學輯要) when looking at it in the dimension of Governing of Others or Governance of humankind (治人) (치인(治人)의 차원에서 본 『대학(大學)』에서 『성학집요(聖學輯要)』로의 학문적 심화)

  • Shin, Chang Ho
    • (The)Study of the Eastern Classic
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    • no.36
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    • pp.375-402
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    • 2009
  • In this study, the researcher put together the changing process of Chinese Confucian into Korean Confucian Thought in the dimension of Chiin 'Governing of Others. By analyzing 'Seonghak jibyo' which is reinterpretation of 'Daehak' and also academic enrichment, the researcher investigated the aspects of acceptance of 'Daehak' in Joseon Period. 'Daehak' was the basic textbook for 'Emperorship Learning'(帝王學, 'Jewang Hak') as well as 'Sage Learning'(聖學, 'Seong Hak') over the whole Joseon Period, and it can be understood that 'Seonghak jibyo'- the Essentials of Sagely Learning compiled by Yulgok(栗谷) is the totalization of such learning. Yulgok organized the system of 'Seonghak jibyo' largely in five volumes and placed Samgangnyeong(三綱領, Three Doctrines or Essential Principles) and Paljomok(八條目, Eight Articles) of 'Daehak' in an appropriate manner. Among those, 'Chiin' was discussed intensively in the Volume Three, 'Jeonga'(正家-Family in Correct State) and also the Volume Four, 'Uijeong'(爲政 the king exercises government by means of his virtue). In the volume, 'Jeonga', Yulgok clearly arranged the core virtues for which the family is obliged to put into practice in everyday life having segmented the contents of the doctrine of Jega(齊家-to order family relationships) in 'Daehak', and, in 'Uijeong', Yulgok deepened the contents of 'Chiguk Pyeongcheonha'(治國平天下, ordering the state, bringing peace to the whole world) and presented consciousness on the spirit of contemporary as well as the practice of the state managements in an affirmative manner. These prove the validity of learning steps by presenting the practice guideline to fit the situation while well preserving the basic system of Confucian thought that leads to 'Chiin' (治人-'Governing of Others' or Governance of humankind) based on 'Sugi'(修己, the cultivation of the self). And such viewpoints feature the characteristics of Joseon Confucian Thought which had been through more abundant enrichment process than Chinese Confucian. Therefore, Yulgok's thoughts expounded in The Essentials of Sagely Learning(聖學輯要, 'Seonghak jibyo') can be regarded as criteria to understand humanity and arts cherished by Joseon people, as well as the distinctive features of politics.

Expression of Arabidiopsis CAX4 in tomato fruits increases calcium level with no accumulation of other metallic cations

  • Jeong, Se-Woon;Han, Jeung-Sul;Kim, Kyung-Min;Oh, Jung-Youl;Kim, Byung-Oh;Kim, Chang-Kil;Chung, Jae-Dong
    • Journal of Plant Biotechnology
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    • v.35 no.4
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    • pp.337-343
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    • 2008
  • We generated transgenic tomato plants with Arabidopsis thaliana $H^+$/cation exchanger gene (C4X4) by Agrobactrium-mediated transformation. We confirmed transgene copy number and transcription by Southern and Northern blot analyses. The intact CAX4-expressing tomato (Lycopersicon esculentum) fruits contained 63-71% more calcium ($Ca^{2+}$) than wild-type fruits. Moreover, ectopic expression of C4X4 in tomato fruits did not show any significant increase of the four kinds of metallic cations analyzed ($Mg^{2+}$, $Fe^{2+}$, $Mn^{2+}$, and $Cu^{2+})$. The C4X4-expressing tomato plants including their fruits did not show any morphological alternations during whole growth period. These results suggest the enhanced Ca-substrate specificity of CAX4 exchanger in tomato. Therefore, intact CAX4 exchanger can be a useful tool for $Ca^{2+}$ nutrient enrichment of tomato fruits with reduced accumulation of undesirable cations.

Effect of Saccharides on Anthocyanin Pigments from Raspberries (나무딸기 Anthocyanin 색소(色素)에 미치는 당류(糖類)의 영향)

  • Joo, Kwang-Jee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.11 no.2
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    • pp.21-25
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    • 1982
  • The changes in color and anthocyanins from raspberries which was added various saccharides and stored at room temperature, $5^{\circ}C$ and $-20^{\circ}C$, were investigated. (1) There are little changes in sugar density, pH, and acidify for 80 days. (2) Optical density of the juice (at 520nm) and the total anthocyanin content decreased during the storage period, the total anthocyanin content remains more than juice of raspberries. (3) Many saccharides effectively maintained the enrichment of absorbance at 520nm duriag storage. Hexose, especially D-galactose, had the most hyperchromic effect followed by disaccharides and then pentose. (4) The stability of anthocyanin pigment in the presence of sugar was markedly influenced by storage temperature. Especially cold temperature $(5^{\circ}C)$ was good for holding the pigment.

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Chemical Analysis of Water Soluble Aerosols at Kosan, Cheju lsland (제주도 고산에서 수용성 에어로졸의 화학적 성분 분석)

  • 이호근;박경윤;서명석;장광미;강창희;허철구
    • Journal of Korean Society for Atmospheric Environment
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    • v.11 no.3
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    • pp.245-252
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    • 1995
  • Atmospheric aerosols were collected by a High Volume Tape Sampler from March 1992 to December 1993 ar Korean, Cheju, Korea. The water soluble ion concentrations in aerosol were analyzed. The concentrations of cations (N $a^{+}$, $K^{+}$, $Ca^{2+}$, $Mg^{2+}$, N $H_{4}$$^{+}$) were determined by an Inductively Coupled Plazma(ICP) or an Atomic Absorption Spectrometer(AAS), and those of anions (C $l^{[-10]}$ , N $O_{3}$$^{[-10]}$ , S $O_{4}$$^{2-}$) were analayzed by the capillary electrophoresis method. The $Ca^{2+}$, S $O_{4}$$^{2-}$ and N $O_{3}$$^{[-10]}$ concentrations in spring were higher than those in other seasons. The lowest concentrations of these elements were found in summer, largely due to scavenging by frequent rains. Especially the $Ca^{2+}$ concentration on April was three to four times higher than the annual mean concentration. The enrichment factor(E.F.) of each element was calculated. The annual mean E.F. values of the $Ca^{2+}$, $Mg^{2+}$ and C $l^{[-10]}$ in 1992 were the same as those in 1993 except $k^{+}$ and S $O_{4}$$^{2-}$. The correlation formula between all cations and anions for the whole period was Anions = 0.759 * Cations + 0.066.Cations + 0.066.

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Isolation and Characterization of Denitrification Bacteria (탈질 세균의 분리 및 특성)

  • 차월석;최형일;이동병;차진명
    • KSBB Journal
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    • v.18 no.6
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    • pp.461-465
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    • 2003
  • Five denitrifying bacteria, which were identified as Pseudomonas sp., were isolated by the enrichment culture technique. The most effective denitrifying bacterium was named as Pseudomonas DWS, which was cultivated at anoxic condition. The optimal growth temperature and pH were 30$^{\circ}C$ and 7-8, respectively. Cell growth almost revealed a stationary phase at 18 hours after cultivation and nitrate was degrade 99.9% during this period. Therefore, it is suggested that Pseudomonas DWS could be effectively used for the biological treatment of wastewater containing nitrogen compounds.

A STUDY FOR DOSE DISTRIBUTION IN SPENT FUEL STORAGE POOL INDUCED BY NEUTRON AND GAMMA-RAY EMITTED IN SPENT FUELS

  • Sohn, Hee-Dong;Kim, Jong-Kyung
    • Journal of Radiation Protection and Research
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    • v.36 no.4
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    • pp.174-182
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    • 2011
  • With the reactor operation conditions - 4.3 wt% $^{235}U$ initial enrichment, burn-up 55,000 MWd/MTU, average power 34 MW/MTU for three periods burned time for 539.2 days per period and cooling time for 100 hours after shut down, to set up the condition to determine the minimum height (depth) of spent fuel storage pool to shut off the radiation out of the spent fuel storage pool and to store spent fuels safely, the dose rate on the specific position directed to the surface of spent fuel storage pool induced by the neutron and gamma-ray from spent fuels are evaluated. The length of spent fuel is 381 cm, and as the result of evaluation on each position from the top of spent fuel to the surface of spent fuel storage pool, it is difficult for neutrons from spent fuels to pass through the water layer of maximum 219 cm (600 cm from the floor of spent fuel storage pool) and 419 cm (800 cm from the floor of spent fuel storage pool) for gamma-ray. Therefore, neutron and gamma-ray from spent fuels can pass through below 419 cm (800 cm from the floor) water layer directed to the surface of spent fuel storage pool.

Monthly Changes in Benthic Macroinvertebrate Communities in Different Saprobities in the Suyong and Soktae Streams of the Suyong River (수영강의 수영천 및 석대천의 저서성 대형무척추동물의 부수성에 따른 월별 군집 변이)

  • Kang Da Hyeung;Tae-Soo Chon;Young-Seuk Park
    • The Korean Journal of Ecology
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    • v.18 no.1
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    • pp.157-177
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    • 1995
  • Monthly changes in communities of benthic macroinvertebrates collected in the Suyong and Soktae stream of the Suyong river were investigated from September 1993 to August 1994. The total number of species collected during the study period ranged from seven to seventy six species according to pollution levels at the study sites. Monthly changes in species richness appeared differently in different taxonomic assemblages. In chironomids differences in species richness responding to different levels of saprobity were shown consistently as time proceeded. In Ephemeroptera species richness at the relatively clean sites responded sensitively to slight enrichment. In connection with species richness the monthly changes in densities in taxonomic assemblages also appeared to effectively represent environmental impacts. Species diversity generally represented the pollution status also, however the monthly variations at the study sites appeared to be relatively high. The clustering analysis showed that the communities collected at polluted sites were grouped closely, and the communities collected at the relatively clean sites were clustered to the same stream although the degree of community association was low, Through the Principal Component Analysis, the impact of Pollution was reflected in a great degree in overall community variations.

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Enhancing Factors of Electricity Generation in a Microbial Fuel Cell Using Geobacter sulfurreducens

  • Kim, Mi-Sun;Cha, Jaehwan;Kim, Dong-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.22 no.10
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    • pp.1395-1400
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    • 2012
  • In this study, we investigated various cultural and operational factors to enhance electricity generation in a microbial fuel cell (MFC) using Geobacter sulfurreducens. The pure culture of G. sulfurreducens was cultivated using various substrates including acetate, malate, succinate, and butyrate, with fumarate as an electron acceptor. Cell growth was observed only in acetate-fed medium, when the cell concentrations increased 4-fold for 3 days. A high acetate concentration suppressed electricity generation. As the acetate concentration was increased from 5 to 20 mM, the power density dropped from 16 to $13mW/m^2$, whereas the coulombic efficiency (CE) declined by about half. The immobilization of G. sulfurreducens on the anode considerably reduced the enrichment period from 15 to 7 days. Using argon gas to create an anaerobic condition in the anode chamber led to increased pH, and electricity generation subsequently dropped. When the plain carbon paper cathode was replaced by Pt-coated carbon paper (0.5 mg $Pt/cm^2$), the CE increased greatly from 39% to 83%.

The Stock Price Response of Palm Oil Companies to Industry and Economic Fundamentals

  • ARINTOKO, Arintoko
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.99-110
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    • 2021
  • This study aims to examine empirically the industry and economic fundamental factors that affect the stock prices of the leading palm oil company in Indonesia. The dynamics of stock price are analyzed using the autoregressive distribution lag (ARDL) model both for symmetric and asymmetric effects. The data used in this study are monthly data for the period from 2008:01 to 2020:03. In the long run, the company stock price moves in line with the competitor company stock price at the current time. The palm oil price has a positive effect on the stock price. Meanwhile, inflation negatively affects the stock price in the short run. The estimated equilibrium correction coefficient indicates a reasonably quick correction of the distortion of the stock price equilibrium in monthly dynamics. However, fundamental factors have asymmetric effects, especially the response of stock price when these factors decrease rather than increase in the short run. Stock prices that are responsive to declines in fundamental performance should be of particular concern to both investors and management in their strategic decision making. The results of this study will contribute to the enrichment of literature related to stock prices from the viewpoint of economic analysis on firm-level data.