• 제목/요약/키워드: Heavy metal transport

검색결과 58건 처리시간 0.023초

하전모자이크 막을 사용하여 중금속이온의 분리 (Separation of Heavy Metal Ions across Novel Mosaic Membrane)

  • 송명관;이장우;양원강
    • 한국막학회:학술대회논문집
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    • 한국막학회 2005년도 추계 총회 및 학술발표회
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    • pp.96-101
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    • 2005
  • A theory for the material transports through ion exchange membrane has been developed on the basis of nonequilibrium thermodynamics by removing the assumption of solvent flow in the previous paper and applied to a detailed study of the ionic transport properties of new charged mosaic membrane(CMM) system. The CMM having two different fixed charges in the polymer membrane indicated unique selective transport behavior then ion-exchange membrane. The separation behavior of ion transport across the CMM with a parallel array of positive and negative functional charges were investigated. It was well-known the analysis of the volume flux and solute flux based on nonequilibrium thermodynamics. Our suggests preferential salt transport across the charged mosaic membranes. Transport properties of heavy metal ions, $Mg^{2+}$, $Mn^{2+}$and sucrose system across the charged mosaic membrane were estimated. As a result, we were known metal salts transport depended largely on the CMM. The reflection coefficient indicated the negative value that suggested preferential material transport and was independent of charged mosaic membrane thickness.

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Synthesis and Selective Transport Properties of Cleft-Type Ionophores Having Two Convergent Hydroxamic Acid Functions

  • 김덕희;최미정;장석규
    • Bulletin of the Korean Chemical Society
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    • 제22권7호
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    • pp.699-702
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    • 2001
  • A series of cleft-type ionophores having two convergent hydroxamic acid functions are prepared and their selective ionophoric properties toward heavy metal and transition metal ions have been investigated. Hydroxamic acids 3 exhibited a prominent selectivity toward heavy metal ions of Hg2+ and Pb2+, and transition metal ions of Cu2+ over other transition metal and alkaline earth metal ions from slightly acidic source phase (pH 6) to an acidic receiving phase (pH 1). Selective ionophoric properties toward Pb2+ and Cu2+ ions over other surveyed metal ions are also confirmed by the FAB-MS measurements.

금속전달 유전자(MTP1)의 과발현 애기장대에서 발현 위치에 따른 내성 증가 연구 (Overexpression of the Metal Transport Protein1 gene (MTP1) in Arabidopsis Increased tolerance by expression site)

  • 김동균
    • 문화기술의 융합
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    • 제5권3호
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    • pp.327-332
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    • 2019
  • 현대 과학자들은 식물정화공정과 같은 새로운 기술로 중금속을 제거하려고 한다. 이런 최첨단 기술 중 하나는 토양의 특정 중금속을 제거하는 형질 전환 식물을 개발하는 것이다. 본 연구자는 T. goingense Metal Transport Protein 1 유전자와 TgMTP1 : GFP 유전자를 발현하는 형질 전환 벡터를 구축했다. 형질전환체 식물을 선택하여 형질 전환 된 유전자를 애기 장대 게놈에서 확인했다. 발현은 Arabidopsis 세포, 조직 및 기관의 여러 부분에서 확인되었다. Arabidopsis thaliana에서 TgMTP1 과발현하는 식물에 중금속이온이 처리되었을 때 형질 전환 식물체는 비 형질 전환 체보다 중금속 내성이 높았다. 추가 연구를 위해 4 (Zn, Ni, Co, Cd.)가지 중금속에 대한 내성이 향상된 형질 전환 식물을 선택했다. 선택된 T3 TgMTP1 과다 발현 애기 장대 식물은 중금속에 내성이 증가된다. 이 식물은 액포 내에 중금속을 축적하고 동시에 원형질막에 발현되는 MTP1 유전자의 발현을 특징으로 한다. 결론적으로, 이러한 식물은 식물 정화 응용 분야 및 내성이 증가 된 식물로 사용될 수 있다.

오염된 토양층내의 중금속 이동 특성 (Transport Characteristic of Heavy Metals in Contaminated Soil)

  • 조재범;현재혁;정진홍;김원석
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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    • pp.236-239
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    • 1998
  • This research was performed to check the transport characteristics of heavy metals in contaminated soil, that is, the influence of humic acid and phosphate on transport characteristics of heavy metals was studied. From the results of column mode experiments about heavy metal behavior, the order time to reach breakthrough and equilibrium was soil + humic acid( 20g ) > soil + humic acid ( 5 g ) > soil without Humic acid addition > soil+humic acid( 50g ). It is because the dissolved organic carbon content increased as the soil organic matter content increased. As the phosphate increased, so did the time to reach breakthrough and equilibrium. The order of time was soil + phosphate( 50 mg ) > soil + phosphate( 20 mg ) > soil . phosphate( 10 mg ) > soil without phosphate addition. It is because the phosphate ion worked as alkalinity donor and the calcium ion co-injected worked as the accelerator of coprecipitation of heavy metals.

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구리${\cdot}$아연과 비교한 보리 엽록체의 광합성 기구에 미치는 수은 이온의 특이한 효과 (Mercury-Specific Effects on Photosynthetic apparatus of Barley Chloroplasts Compared with Copper and Zinc Ions)

  • 문병용;전현식
    • 한국환경과학회지
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    • 제1권1호
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    • pp.1.1-11
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    • 1992
  • To find heavy metal-specific effects on the photosynthetic apparatus of higher plants, we investigated effects of $CuCl_2$, HgCl_2$ and $ZnCl_2$ on electron transport activity and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings. Effects on some related processes such as germination, growth and photosynthetic pigments of the test plants were also studied. Germination and growth rate were inhibited in a concentration-dependent manner by these metals. Mercury was shown to be the most potent inhibitor of germination, growth and biosynthesis of photosynthetic pigments of barley plants. In the inhibition of electron transport activity, quantum yield of PS II, and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings, mercury chloride showed more pronounced effects than other two metals. Contrary to the effects of other two metals, mercury chloride increased variable fluorescence significantly and abolished qE in the fluorescence induction kinetics from broken chloroplasts of barley seedlings. This increase in variable fluorescence is due to the inhibition of the electron transport chain after PS ll and the following dark reactions. The inhibition of qE could be attributed to the interruption of pH formation and do-epoxidation of violaxathin to zeaxanthin in thylakoids by mercury. This unique effect of mercury on chlorophyll fluorescence induction pattern could be used as a good indicator for testing the presence and/or the concentration of mercury in the samples contaminated with heavy metals.

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서남해안 연근해저 퇴적물의 중금속 함량 및 분포 (Some heavy metal concentration of surface sediments from the southwestern coast of Korea)

  • 전수경;조영길
    • 한국환경과학회지
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    • 제11권12호
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    • pp.1299-1305
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    • 2002
  • Thirty sediment samples of the <63${\mu}{\textrm}{m}$ fraction collected from the southwestern coast of Korea were analysed for their heavy metal (Fe, Mn, Cr, Co, Cu, Ni, Zn and Pb) concentration. The results show that sediment texture plays a controlling role on the total metal concentrations and their spatial distribution. A single lM HCl extraction procedure was used in order to assess the environmental risk of heavy metals in bottom sediments. The non-residual fraction was the most abundant pool for Mn and Pb in most samples, which means that this metals are highly avaliable in these sediments. Cr, Ni, Fe, Co, Zn and Cu were mainly associated with the residual fraction, suggesting that their concentrations are controlled significantly by transport processes with the fine particles as carriers from diffuse pollution source. Concentration enrichment ratios(CER) were calculated from the non-residual contents and their values allowed us to classify the sediments according to their environmental risk.

대기 중 잔류성 유기오염물질과 중금속의 특성과 현황 (Characteristics and Status of Persistent Organic Pollutants and Heavy Metals in Ambient Air)

  • 김영성
    • 한국대기환경학회지
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    • 제19권2호
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    • pp.113-132
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    • 2003
  • In May 2001, the Stockholm Convention on Persistent Organic Pollutants (POPs) for phasing out and eliminating POPs was signed by 90 countries at the Diplomatic Meeting in Stockholm. In 1998, three years before the Convention, the protocols on POPs and heavy metals were adopted by the United Nations Economic Commission for Europe under the Convention on Long-Range Transboundary Air Pollution. Growing attention on POPs and heavy metals during the past 10 years is primarily due to their toxicity in minute quantities. POPs and some metal compounds are even more toxic because of their bioaccumulation potentials associated with a high lipid solubility. Furthermore, owing to their persistence and semi - volatility, they are widely distributed in the environment, traveling great distances on wind and water currents. Recent international cooperation to address POPs and heavy metals has focused on these issues. Long -range transport of those pollutants are particularly concerned since Korea is located downwind of prevailing westerlies from China. In this paper, a review is provided to assess the properties, sources, emissions, and atmospheric concentrations on POPs and heavy metals.

Transport Properties of Charged Mosaic Membrane Based on Non-equilibrium Thermodynamics

  • Song, Myung-Kwan;Yang, Wong-Kang
    • Korean Membrane Journal
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    • 제7권1호
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    • pp.67-70
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    • 2005
  • It is well known as the role of ion exchange membrane with functional group in membrane matrix. Recently, we were reported that the charged mosaic membrane within parallel array of negative and positive charge groups. In this study we are reported the properties for the various transport coefficients of metal and heavy metal ions across charged mosaic membrane based on non-equilibrium thermodynamics is not based on equilibrium state.

pH Effect on Lead Transport into astrocytes by Divalent Metal Transporter 1 (DMT1/Nramp2)

  • Cheong, Jae-Hoon;Desmond I. Bannon;Josep P. Bressler
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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    • pp.91-91
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    • 2001
  • Nramp2, also known as DMT1 and DCT1, is a 12-transmembrane domain protein responsible for dietary iron uptake as well as metal ions such as lead, manganese, zinc, copper, nickel, cadmium, and cobalt. High expression of DMT1 increase lead uptake, and DMT1-dependent lead transport was H -dependent and inhibited by iron ions. The molecular mechanism of lead transport in CNS is as yet unknown. although interactions between iron and lead at the level of absorption have been known for some time. The process of lead uptake into astrocytes was not known yet. Nramp2 may mediate transport of heavy metal into astrocytes. We investigated whether Nramp2 mediate transport of lead into astrocytes. And we do whether Nramp2 was expressed highly by deprivation of iron in Astrocytes, and lead uptake into astrocytes was influenced by expression of Nramp2. Immortalized human fetal astrocyte(SV-FHA) cells were cultured in medium containing Dulbecco's modified Eagle's medium and treated with Deferoxamine. Northern blot analysis was done for determining mRNA level of DMT1 and lead uptake assay was done in incubation condition of pH 5.5 and 7.4.

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A study on heavy metal migration in fly ash/bentonite using a reactive transport model

  • Jung, Yoo-Jin;Cho, Hee-Chan
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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    • pp.629-636
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    • 2003
  • The retardation of heavy metals in a mixture of fly ash and bentonite was studied as a potential barrier material for a landfill. Column tests were conducted using synthetic leachate having 100 mg/L and 50 mg/L of lead (Pb) and cadmium (Cd), respectively. Results indicated that the mixture had obvious retardation ability for heavy metals. To investigate the retardation factor caused by adsorption, batch adsorption tests were conducted at various concentrations. Test results were correlated with both Langmuir and Freundlich isotherms. The adsorption of the lead ion was applicable to the Langmuir isotherm and the adsorption of the cadmium ion was applicable to the Freundlich isotherm. In addition, based on experimental results, the migration characteristics of heavy metals through the bed of fly ash and bentonite mixture were investigated using the PHREEQC, a reactive transport model, under the real conditions of the landfill liner.

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