• 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.

• 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.

• Bulletin of the Korean Chemical Society
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• 제23권8호
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• pp.1085-1088
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• 2002

Calix[6]arene having both carboxylic acid (1,3,5-) and carboxamide (2,4,6-) in an alternative way was synthesized. Transport rates of alkali and alkaline-earth metal ions were tested in bulk liquid membrane and polymer inclusion membrane. Ba2+ ion was found to give the highest transport rate among tested metal ions in both BLM and PIM systems. In PIM system, high durability (longer than 30 days) of the membrane was observed.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.930-934
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• 2005

A chloroform membrane system containing a given mixture of benzylaza-12-crown-4 and oleic acid is introduced for the selective and efficient transport of $Pb^{2+}$ ion. The transport was capable of moving metal ions ‘up-hill’. In the presence of ${S_2O_3}^{2-}$ion as a suitable metal ion acceptor in the receiving phase, the amount of lead ion transport across the liquid membrane after 150 minutes is (95.0 ${\pm}$ 1.7)%. The selectivity and efficiency of lead transport from aqueous solution containing $Tl^+,\;Ag^+,\;Mg^{2+},\;Ca^{2+},\;Co^{2+},$ $Ni^{2+},\;Cu^{2+},\;Zn^{2+},\;Hg^{2+}$ and $Cd^{2+}$were investigated. In the presence of thiosulfate as a suitable masking agent in the source phase, the interfering effects of $Ag^+\;and\;Cu^{2+}$ were diminished drastically.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.191-193
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• 2006

YBCO wire has a metal substrate to improve the texture structure and highly conductive layers to increase the cryogenic stability. When AC current flows in the YBCO wire, magnetic field which is generated by the AC current magnetizes the metal substrate and induces the eddy current in the stabilizing layer. To examine the effect of the metal substrate and the conducting layer on the transport current loss of YBCO wire, this paper presents the transport current loss of YBCO wire which has metal substrate and conductive layer. YBCO wire with Ni-W substrate and copper layer were chosen as the model HTS wire for numerical calculation. Finite element method has been used to calculate the transport loss and the results of numerical calculation was compared with analytic calculation suggested by Norris.

• Carbon letters
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• 제14권3호
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• pp.162-170
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• 2013

The performance of graphene-based electronic devices is critically affected by the quality of the graphene-metal contact. The understanding of graphene-metal is therefore critical for the successful development of graphene-based electronic devices, especially field-effect-transistors. Here, we provide a review of the peculiar properties of graphene-metal contacts, including work function pinning, the charge transport mechanism, the impact of the process on the contract resistance, and other factors.

• Korean Journal of Acupuncture
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• 제31권2호
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• pp.49-55
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• 2014

Objectives : Five transport points are often used in acupuncture treatment. However, there is no clear explanation about the reason why the five transport points are matched five phases in this manner. Therefore, we reviewed the literatures and theses about the principal of matching and researched a new way to understand the reason. Methods : We found 8 theses and 3 literatures related to the matching of five transport points to five phases by searching the web sites. And, we reviewed the principal of matching and researched another new way to understand the reason why they are matched so. Results and Conclusions : In the viewpoint of the natural state and function of five phases, the start points arising in yin- and yang-meridian are matched to wood and metal respectively. Therefore, well point matches the wood and metal in yin- and yang-meridian respectively. And by following the flow of five transport points, the other points match with fire, earth, metal, water in yin-meridian and water, wood, fire, and earth in yang-meridian.

• 한국전기전자재료학회논문지
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• 제13권5호
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• pp.365-370
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• 2000

Schottky contacts on n-In$\_$0.53//Ga$\_$0.47//As have been made by metal deposition on substrates cooled to a temperature of 77K. The current-voltage and capacitance-voltage characteristics showed that the Schottky diodes formed at low temperature had a much improved barrier height compared to those formed at room temperature. The Schottky barrier height ø$\_$B/ was found to be increased from 0.2eV to 0.6eV with Ag metal. The saturation current density of the low temperature diode was about 4 orders smaller than for the room temperature diode. A current transport mechanism dominated by thermionic emission over the barrier for the low temperature diode was found from current-voltage-temperature measurement. Deep level transient spectroscopy studies exhibited a bulk electron trap at E$\_$c/-0.23eV. The low temperature process appears to reduce metal induced surface damage and may form an MIS (metal-insulator-semiconductor)-like structure at the interface.

• Archives of Pharmacal Research
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• 제11권2호
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• pp.81-86
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• 1988

The transfer of cupric sulfate across the rat small intestine in vitro was studied by perfusion method using the segments of everted rat small intestine. Copper transport was approximately propotional to the metal concentration in the mucosal solution and no difference was observed in the metal transport among rat duodenum, jejunum and ileum. It was suggested from these results that copper transport across the rat small intestine would occur by passive diffusion. The effect of various chelating agents on copper transport across the rat small intestine n vitro and its uptake by the intestine were also studied. Copper transport was greatly enhanced in the presence of EDTA and NTA. Copper uptake decreased to a greater extent in the presence of EPTA and NTA.

• The Korean Journal of Ceramics
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• 제4권2호
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• pp.103-113
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• 1998

By using a gas-tight electrochemical cell, we can perform high-temperature coulometric titration and measure electronic transport properties to determine the elecronic defect structure of metal oxides. This technique reduces the time and expense required for conventional thermogravimetric measurements. The components of the gas-tight coulometric titration cell are an oxygen sensor, Pt/yttria stabilitized zirconia(YSZ)/Pt, and an encapsulated metal oxide sample. Based on cell design, both transport and thermodynamic measurements can be performed over a wide range of oxygen partial pressure ($pO_2=10^{-35}$ to 1 atm). This paper describes the high-temperature gas-tight electrochemical cells used to determine electronic defect structures and transport properties for pure and doped-oxide systems, such as YSZ, doped and pure ceria $(Ca-CeO_2 \;and\; CeO_2)$, copper oxides and copper-oxide-based ceramic superconductors, transition metal oxides, $SrFeCo_{0.5}O_x,\; and \;BaTiO_2$.