• Title/Summary/Keyword: Lead transport

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Analysis of the Transport Characteristics of Bulk Cargo in Freight Stations Located Behind Trade Ports (무역항 배후 화물철도역의 벌크화물 운송특성 분석)

  • Choi, Chang-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.15 no.6
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    • pp.47-61
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    • 2016
  • The present study analyzed the railway transport characteristics of bulk cargo flowing in and out of trade ports in South Korea. Bulk cargo transport in freight stations located behind trade ports was examined using actual flow data, and new implications were drawn accordingly. The results showed that bulk cargo volume in freight stations located behind trade ports is gradually decreasing, and it is also failing to secure a competitive edge against road transport. This downfall can be mainly attributed to the decrease in competitiveness of railway transport as well as the emergence of new trade ports that do not have lead-in track for port. Therefore, greater effort is required to strengthen the connection between new trade ports and railway freight stations.

Establishing an integrated support system for tourism transportation in a marine city area - A comparison of Yeosu and the Bay Area - (해양도시권 관광교통 통합지원체계 구축방향 연구 - 여수시권과 Bay Area의 비교연구를 중심으로 -)

  • Choi, Chang-Ho
    • Journal of Korea Port Economic Association
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    • v.31 no.3
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    • pp.121-140
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    • 2015
  • The present study examines how to construct a transport system for tourism in the marine city area of Yeosu. An effective tourism transport system is needed in Yeosu to promote ocean tourism in Korea's southern coastal region. The problems in Yeosu's transport system for ocean tourism were identified by comparing it with the Bay Area in the United States; future improvement methods were deduced accordingly. The transport support system for ocean tourism in Yeosu area was insufficient in many aspects compared with the Bay Area, such as intercity transportation, urban transport systems, and transport information systems. Thus, this study suggests various approaches to building a new ocean tourism transport support system in Yeosu. Connecting transport modes and ocean tourism resources, such as linking intercity and urban transport modes with ocean tourism transport modes, is suggested. It is also recommended that a cooperative transport support system be established for ocean tourism in the neighboring regions of Yeosu. Furthermore, an integrated transport information system for ocean tourism needs to be provided to connect the system efficiently with ocean tourists. This integrated transport support system could lead to a decrease in the cost and time needed for travel.

Impairment of Polar Auxin Trnaport by Protein Kinase Inhibitors in Etiolated Pea Seedlings

  • Nam, Myung Hee;Kang, Bin G.
    • Journal of Plant Biology
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    • v.38 no.4
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    • pp.343-348
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    • 1995
  • Treatment of Pisum sativum tissue with the protein kinase inhibitor staurosphorine resulted in impairment of 3H-indoleacetic acid transport in etiolated stem segments. The transport inhibitiion was accompanied by an increase in net uptake of labeled auxin in the tissue. The magnitude of auxin accumulation in tissue treated with the phytotropin N-1-naphthylphthalaic acid (NPA) which specifically blocks the efflux of auxin in the plasma membrane was reduced by the protein kinase inhibitor, suggesting that inhibition of protein phosphorylation could lead to hindrance of the auxin-exporting function of NPA receptors. The flavonoid genistein which is also known to inhibit protein kinase likewise reduced NPA-induced auxin accumulation. However, the flavonoid did not bring about auxin accumulation by itself, nor did it inhibit auxin transport. In view of the finding that the flavonoid also competes with NPA for a common binding site, a mechanism for the flavonoid effect on the NPA action will be proposed.

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The Fourier Analysis on DSA and P$_2$SA for Discrete-Ordinates Solutions of Neutron Transport Equations

  • Noh, Taewan
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.10a
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    • pp.103-108
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    • 1995
  • By applying the P$_1$ and P$_2$ equations to the operator form of a synthetic acceleration, we derive the p,-acceleration (diffusion synthetic acceleration: DSA) and P$_2$-acceleration (p$_2$SA) schemes in one dimensional slab geometry. We Fourier-analyze the derived acceleration schemes with the discrete-ordinates transport equation and showed that the DSA outperforms the P$_2$SA. These results confirm that one cannot simply assume that replacement of the DSA with a higher order approximation will lead to a better acceleration performance.

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Characterization of Absorption Process of Taurine Across Rat Small Intestine

  • Kim, Kyung-Soon
    • Archives of Pharmacal Research
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    • v.6 no.2
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    • pp.109-114
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    • 1983
  • A mechanism of taurine transfer across the rat small intestine was elucidated by using the in situ recirculation perfusion or loop method. Taurine uptake was saturable, Km= 39.9 mM, and energy dependent, and required sodium. The close structural analogues, aminomethane sulfonic acid, .gamma.-amino-butyric acid, hypotaurine, and .betha.-alanine, reduced significantly taurine uptake when present in 10-fold excess. The .alpha.-amino acid, glycine, did not inhibit uptake. Hence, all of these findings lead to a conclusion that a carrier-mediated transport system for taurine exists in the small intestine.

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Selective Transport of Pb(II) Ion by Acyclic Polyethers Bearing Amide End-Groups

  • 김종승;이상철;김응태;조재훈;조문환;유재형;이종해
    • Bulletin of the Korean Chemical Society
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    • v.18 no.12
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    • pp.1256-1260
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    • 1997
  • A series of acyclic polyethers bearing amide end-groups and lipophilic alkyl chains (3-5) were successfully synthesized with quantitative yields. Based upon the transport experiment in a bulk liquid membrane (BLM) system and solvent extraction, a very high selectivity of Pb2+ over other transition metal cations was observed. Measurement of thermodynamic parameters for complexation in methanol at 25 ℃ gave a strong evidence for excellent selective complexation for lead ion over other transition metal ions.

A Research on Prospect of International Intermodal Transport in North-East Asia and Establishment of Transit Transport Agreement (동북아 국제복합운송 전망과 통과운송 협약의 추진방안 연구)

  • Park, Yong-An
    • Journal of Korea Port Economic Association
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    • v.27 no.2
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    • pp.163-182
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    • 2011
  • This research addresses the prospect of international intermodal transport in North-East Asia and studies the necessity of an agreement in transit transport in the region. Due to the division of labour among countries in the region and the globalization of firm's activities, international intermodal transport has been actively developed and is expected to grow continually. In order to lead the operation of international intermodal transport in North-East Asia, main players such as China and Russia have strengthened cooperation of regional logistics and made agreements in transit transport with contiguous countries. After analysing the current situation and reviewing prospects of international intermodal transport and transit transport in North-East Asia, this research proposes the requirement of regional agreement of transit transport on the basis of the United Nations Convention on the Law of the Sea (UNCLOS) for promoting international intermodal transport in North-East Asia.

Irregular Distribution of Lead in Groundwater in Door County, Wisconsin (위스컨신주 도어지역의 지하수내 납성분의 불규칙한 분포에 관한 연구)

  • 우남칠
    • The Journal of Engineering Geology
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    • v.3 no.3
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    • pp.241-252
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    • 1993
  • Lead bas been found in the groundwater in Door County, Wiscorsin, with temporally and spatially irregular distribution in concentration. Correlation coeffidents were calculated among lead indicators in groundwater(frequency of lead detections, mean and maximum concentration of lead detections) and seven independent variables(stucture and geographic factors of wells, hydrogeological factors at lead-arsenate mixing sites and the level of soil contamination) which are possibly related to the lead level in groundwater. The significance of relationships was determined statistically by a t-test at the 90% confidence level, and indicated that the spatially located lead-arsenate mixing sites provided the lead in groundwater in the study area. A total of 112 groundwater samples were collected from 5 house wells with previous lead detects. Lead was detected in partides on ifiter papers with $0.45{\;}\mu\textrm{m}$ pore size, but not in filtrates. The result of chemical analysis for lead indicates that lead is associated with partides in groundwater in Door County. Subsequently, the irregular distribution of lead in the county results from the transport of particulate lead along the advective groundwater movement through the preferential pathways sucn as vertical and bedding-plane joints.

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The Characteristics of pH Variations and Lead transport during Electrokinetic Remediation of soil Contaminated by Heavy Metal (중금속 오염토의 Electrokinetic 정화 처리시 pH 발현과 납 제거의 전극 간 특성)

  • 한상재;김수삼
    • Journal of Soil and Groundwater Environment
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    • v.6 no.4
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    • pp.13-23
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    • 2001
  • In this study, the characteristics of pH variations and contaminant distribution in soil are investigated during electrokinetic treatment for the purpose of restoring contaminated soil with heavy metal. For these objects, laboratory test for the kaolin contaminated by lead was performed. During electrokinetic treatment, lead was transported from anode to cathode. And 75% of lead removed within 80% region of the specimen. Most lead, however, that transported from anode to cathode precipitated in the vicinity of cathode compartment, thus the amount of lead removed by electroosmosis was little. Electrokinetic treatment satisfied regulation criteria of Korean Soil Environment Conservation Law within almost region of the specimen. But enhancement methods can be regarded as inevitable requisite for the cathode region.

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