• Title/Summary/Keyword: 물 조절

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Spatial Variability and Contents of Metals in the Surficial Sediments of Youngil Bay, East Coast of Korea (한국 동해안 영일만 표층 퇴적물의 금속 함량과 공간 변화 특성)

  • Um, I.K.;Lee, M.K.;Jeon, S.K.;Jung, H.S;Lim, D.I.
    • Journal of the Korean earth science society
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    • v.24 no.5
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    • pp.477-490
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    • 2003
  • Bottom sediments from Youngil Bay, East Coast of Korea, were analyzed for grain composition as well as elemental compositions and total organic carbon (TOC) content in order to investigate the spatial variability and content of metal elements. Grain size distribution of the sediments seems to be controlled by anticlockwise current pattern with bottom topography of the study area. Spatial variability of TOC and all elemental contents reflects those of grain size, but an exception was found in the harbor area (Old-Port): their contents are high in the central part of the bay with the muddy sediment and decrease toward the sand-dominated coastal zone. However, contents of Ca, Sr, K are high in the sand-dominated coastal zone and contents of some heavy metals (Cd, Cu, Zn) are high in the Old-Port area and the mouth of Hyeongsan River. The correlation matrix and R-mode factor analyses reveal that four important factors controlling the distribution of metals in the bay are sediment grain size (or quartz dilution effect), the formation of sulfide minerals associated with decomposition of organic matters under anoxic geochemical environment, calcium carbonate (mainly shell fragments) and coarse-grained feldspar mineral. According to the metal content of labile fraction an CER (concentration enrichment ratio) value, high accumulation of some heavy metals in the harbor area seems to result not formed by early diagenetic processes under anoxic environment.

In vitro Anti-oxidative and Anti-inflammatory Activities of Horse-bone Extract via Up-regulation of Heme-oxygenase 1 (말뼈추출물의 Hemeoxygenase-1의 발현 조절을 통한 시험관내 항염증 효과)

  • Im, Eun Ju;Lee, Ki-Ja;Cho, Gil-Jae;Kim, Hyun-Kyoung;Kim, Suk;Rhee, Man Hee
    • Journal of agriculture & life science
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    • v.50 no.2
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    • pp.139-150
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    • 2016
  • Few studies have been reported that horse-bone extract(HBE) can prevent and treatment of bone diseases. However, HBE' therapeutic activities are still not fully understood. This study determined whether HBE up-regulates hemeoxygenase 1(HO-1) and this mediates its anti-inflammatory effect in murine macrophages.Nitric oxide(NO) assay, MTT assay and DPPH assay were performed. In addition, Western blotting and real time PCR were used to determine protein expression, and gene expression, respectively. HBE significantly inhibited NO production without observable cytotoxicity. In addition, HBE attenuated inducible nitric oxide synthase (iNOS), cyclooxygenase-2(COX-2) and phospho (p)-ERK protein expressions in LPS(0.1㎍/ml) stimulated RAW264.7 cells. On the other hand, HBE alone up-regulated HO-1 and Nrf-2 expressions, which mediated HBE's anti-inflammatory effect in RAW264.7 cells. Finally, HBE up-regulated HO-1 and impaired ERK1/2 signaling pathways, and thus it may provide protection against cellular oxidation and inflammation.

Innovative Transient Thermal Gradient Control to Prevent Early Aged Cracking of Massive Concrete (매스콘크리트의 열경사 조절에 의한 수화열과 온도균열의 방지)

  • Kim, Seong-Soo;Cho, Tae-Jun;Lee, Jeong-Bae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.12 no.6
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    • pp.164-172
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    • 2008
  • The heat of hydration for early aged mass concrete induces high temperature with the hydration. Control of the temperature difference across a section is an effective strategy to minimize the hydration heat induced cracks for the structures where internal restraint is dominant. The current prevention methods for hydration cracking show some limitations for the control of thermal gradients, and these limitations could make micro and macro cracks in surface and core of concrete. Especially cooling methods can decrease the increasing hydration temperature, but it can not prevent the problem while decreasing temperature. Consequently heating pipes are added simultaneously with the cooling pipes in order to control the temperature gradients between core and surface of the concrete, followed by the finite element analysis (FEA). Based on the FEA, the proposed method using cooling pipe and heating pipes together has been found to be an effective alternative in thermal gradient control, in terms of controlling temperature induced cracks significantly.

종계, 자율조절 능력 상실로 적자폭 커진다

  • 대한양계협회
    • KOREAN POULTRY JOURNAL
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    • v.30 no.2 s.340
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    • pp.60-62
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    • 1998
  • 외환위기로 인한 IMF구제금융의 파장은 환율상승에 따른 생산비의 급격한 상승과 소비위축 등에 의한 축산물 가격하락 등으로 경영부담이 가중되고 있는 가운데 위기가 고조되어 가고 있어 축산물 생산 여건은 악화일로를 걷고 있다. 이러한 최근의 급격한 환경여건 변화에 따른 대책을 강구한다는 것이 쉽지 않지만 현재의 상황을 상기하여 봄으로써 종계$\cdot$부화업계의 자구책을 찾아보고자 경인축산 이광초 사장을 만나 업계의 어려움에 대하여 들어보았다.

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Relative Influence of Sediments, Food and Dissolved Sources on Ag Bioaccumulation in the Amphipod Leptocheirus plumulosus (오염된 퇴적물로부터 해양저서 단각류 Leptocheirus plumulosus의 은(Ag)축적에서 흡수경로의 상대적 기여도 평가)

  • Yoo, Hoon;Lee, In-Tae;Lee, Byeong-Gweon
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.2
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    • pp.87-93
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    • 2002
  • A amphipod, Leptocheirus plumulosus was exposed to Ag contaminated sediments to evaluate relative importance of various uptake routes (sediment, porewater, supplementary food) for Ag bioaccumulation in sediment-dwelling marine invertebrates. Additionally, influence of AVS (acid-volatile sulfide) on the partitioning of Ag to porewater and on the Ag bioavailability was determined to evaluate the utility of AVS criteria for the management of metal contaminated sediment. The experimental sediments were spiked with 4 levels of Ag (0.1-3.3 ${\mu}$mol Ag/g) and AVS concentrations were manipulated to 40 or <0.5 ${\mu}$mol/g, then equilibrated for >2 months to allow pore water/particulate distributions similar to nature. A L. plumulosus was incubated in the contaminated sediments with overlying water for 35d. During the exposure, the amphipods was fed with supplementary food ($TetraMin^{(R)}$) with or without Ag contamination. Following exposure, tissue Ag in L. plumulosus was strongly correlated with the weak acid extractable Ag in sediments ($r^{2}$=0.87, p<0.001). The ratio of AVS to Ag-SEM (Ag extracted simulaneouls with AVS) had a strong influence on porewater Ag concentration, consistent with previous studies. However, Ag bioaccumulation in L. plumulosus was not influenced by AVS concentrations. The amphipods fed Ag contaminated food took up ${\sim}$ 1.8 X Ag accumulated by the amphipods fed uncontaminated supplementary diet. The result suggests that the benthic invertebrates exposed to metal contaminated sediments would accumulate metals largely via ingestion of contaminated sediments and food, with minor contribution from dissolved sources of porewater and overlying water.