• Title/Summary/Keyword: Concentration Gradient

Search Result 583, Processing Time 0.024 seconds

CDDP induces conformational changes in BTV ds RNA rather than forming protein-protein and/or protein-RNA crosslink (cis-Diamminedichloroplatinum(II) (CDDP)에 의한 불루텅 바이러스 이중가닥 RNA의 구조변화)

  • Yang, Jai-Myung
    • Applied Biological Chemistry
    • /
    • v.34 no.2
    • /
    • pp.86-93
    • /
    • 1991
  • cis-Diamminedichloroplatinum(II)(CDDP), an antitumor drug, did not generate crosslink between bluetongue virus (BTV) capsid protein at moderate concentration. Cesium chloride density gradient centrifugation study revealed that protein-RNA crosslink was not detectable in CDDP treated BTV. CDDP treated BTV ds RNA showed remarkable change in the migration pattern in polyacrylamide gel electrophoresis. These results suggest that the reduction of BTV core associated transcriptase activity is most likely by the CDDP adduction to the genomic ds RNA rather than by the protein-RNA crosslink and/or protein-protein cross-link.

  • PDF

The Behavior of Anionic Surfactant Calfax 16L-35 in Electrokinetic Remediation

  • 양지원;이유진;박지연;김상준
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 2003.04a
    • /
    • pp.306-309
    • /
    • 2003
  • Surfactant-enhanced electrokinetic (EK) remediation is an emerging technology that can effectively remove hydrocarbons from low-permeability soils. In this study, the electrokinetic remediation using Calfax 16L-35 was conducted for the removal of phenanthrene from kaolinite. An anionic surfactant Calfax 16L-35 was used at concentrations of 5, 15, and 30g/L to enhance the solubility of phenanthrene. When the surfactant solution was applied to EK system, low electrical potential gradient was maintained because of its ions. Even when the surfactant concentration was high, the removal efficiency of phenanthrene was low After the operation, most of surfactants were remained in soil and there were few in effluent. This phenomena was observed because the migration of Calfax 16L-35 from cathode to anode was predominant over electroosmotic flow which moved in opposite direction. Therefore, the anionic surfactant Calfax 16L-35 is considered to be improper in surfactant - enhanced electrokinetic remediation.

  • PDF

Electrolysis for NiW Functional Alloy Plating (NiW 기능성 합금도금을 위한 전해)

  • Jeong, Goo-Jin;Lee, Churl-Kyoung
    • Journal of the Korean institute of surface engineering
    • /
    • v.44 no.1
    • /
    • pp.1-6
    • /
    • 2011
  • A NiW functional alloy plating was investigated as variables of metal ion concentration, complexing agent, temperature, pH and applied current density. Even if numerous studies on reaction mechanism of NiW induced codeposition were carried out during couples of decade, it has not been acceptable reaction mechanism. This study was focused on the effect of the plating variables on the alloy composition in the NiW alloy plating. Applied current density could control mainly the alloy composition rather than other plating variables. It has also been confirmed that the functional alloy plating such as layered or gradient plating was possible by controlling applied current density.

Potassium Distribution in the Apical Region of Rice Root

  • Rehman Shafiq;Park Moung-Ryoul;Ashraf Muhammad;Yun Song-Joong
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.51 no.4
    • /
    • pp.295-297
    • /
    • 2006
  • Potassium (K) distribution in rice (Oryza sativa L.) root was studied by confocal laser microscopy, using potassium sensitive fluorescent dye potassium-binding benzofuran isophthalate (PBFI). Significantly high intensity of K-specific fluorescence was detected at the root cap region followed by meristematic and basal regions. A negligible or fainted fluorescence was observed at the root hairs area. These results suggest that K is heavily distributed in the apical area of rice root, which may be required in higher concentration for division and extension of cells, as it is the rapidly growing region of the root, moreover, may also be involved in water uptake by creating osmotic gradient across membranes.

Product Phase Control During Interdiffusion Reactions (상호 확산 반응 중의 생성상 제어)

  • Park, Joon-Sik;Kim, Ji-Hoon;Perepezko, John R.
    • Journal of Korea Foundry Society
    • /
    • v.26 no.1
    • /
    • pp.27-33
    • /
    • 2006
  • Phase evolutions involving nucleation stages together with diffusional growth have been examined in order to provide a guideline for determining rate limiting stages during phase evolutions. In multiphase materials systems in coatings, composites or multilayered structures, diffusion treatments often result in the development of metastable/intermediate phases at the reaction interfaces. The development of metastable phases during solid state interdiffusion demonstrates that the nucleation reaction can be one controlling factor. Also, the concentration gradient and the relative magnitudes of the component diffusivities provide a basis for a phase selection and the application of a kinetic bias strategy in the phase selection. For multicomponent alloy systems, the identification of the operative diffusion pathway is central to control phase formation. Experimental access to the nucleation and growth stage is discussed in thin film multi layers and bulk samples.

Formation and Growth of Hydride Blisters in Zr-2.5Nb Pressure Tubes

  • Cheong, Yong-Moo;Gong, Un-Sik;Choo, Ki-Nam;Kim, Sung-Soo;Kim, Young-Suk
    • Nuclear Engineering and Technology
    • /
    • v.33 no.2
    • /
    • pp.192-200
    • /
    • 2001
  • Hydride blisters were formed on the outer surface of Zr-2.5Nb pressure tube by a non- uniform steady thermal diffusion process. A thermal gradient was applied to the pressure tube with a heat bath kept at a temperature of 415$^{\circ}C$ and an aluminum cold finger cooled with flowing water of 15$^{\circ}C$. Optical microscopy and tree-dimensional laser profilometry were used to characterize the hydride blisters with different hydrogen concentrations and thermal diffusion time. Hydride blisters were expected to start at a hydrogen concentration of 30 - 70 ppm and a thermal diffusion time of 4 - 6$\times$10$^{5}$ sec. The hydride blister size increases with higher hydrogen concentrations and longer thermal diffusion time . Some of the samples revealed cracks on the hydride blisters. The ratio of hydride blister depth to height was estimated as approximately 8: 1.

  • PDF

Isolation and Characterization of Lipophorin from Lymantria dispar L. (매미나방(Lymantria dispar L.)의 Lipophorin의 정제 및 특성)

  • 류재구;김학열
    • The Korean Journal of Zoology
    • /
    • v.34 no.1
    • /
    • pp.1-7
    • /
    • 1991
  • Lipophorin of Lymuntrn'adispor L. has been purified by KBr density gradient ultracentrifugation. The properties and synthetic site of lipophorin and quantitative change of lipophorin during development have been determined using electrophoresis and immunological analysis. Lipophorin is composed of ho subunits. apo-Lpl (230.000), ago-Lpll (49,000). ann contains carbohydrates and lipids. Anti-lipophorin showed positive reactions with fat body extract and ovary extract but not with gut extract. The concentration of lipophorin in hemolymph showed gradual decrease during larval and pupal stages. Also. fat body released lipophorin into medium. Immunological test showed some partial identity between lipophorin of Lymantpia dispar and hemolymph proteins (probably lipophorin) of Hyphontria cuneo and Galleria metlonefla.

  • PDF

Streaming potential and groundwater contamination

  • Baker Simon S.;Cull James P.
    • Geophysics and Geophysical Exploration
    • /
    • v.7 no.1
    • /
    • pp.41-44
    • /
    • 2004
  • Measurements of streaming potential can provide a means for the detection and quantification of contaminants in groundwater prior to remediation. However, laboratory determinations of specific electrolyte properties are required for an adequate analysis of the hydraulic gradient in complex situations. Data obtained for the King River in Tasmania confirm a linear relationship linking streaming potential data and hydraulic gradients. Laboratory samples at low concentration (0.001M KCl) indicate values in the range 20-80 mV/cm of water pressure, while for higher concentrations (0.01M KCl) values are less than 25 mV/cm. Similar ion concentrations are observed in the King River, consistent with field correlations indicating values for streaming potential close to 15 mV/cm. In-situ fluid samples are required for more detailed analysis of local anomalies that may be associated with variations in recharge and migration of contaminants.

Influence of Dopamine on Intrarenal Blood Flow in Dog (개의 신내 혈류에 미치는 Dopamine의 영향)

  • 고석태;강호연
    • YAKHAK HOEJI
    • /
    • v.28 no.3
    • /
    • pp.149-160
    • /
    • 1984
  • In order to certify the diuretic mechanism of dopamine, this study was performed in dog. The following results were obtained. Dopamine, when given intravenously, produced diuresis, and increased glomerular filtration rate (GFR), renal plasma flow (RPF), and amount of sodium excreted in urine. When infused directly into a renal artery, dopamine elicited a marked diuresis confined only to the infused side, with concomitant rises in osmolar clearance and sodium excretion as well as a slight increase in free water clearance. Simultaneously total renal plasma flow and medullary plasma flow increased markedly with a increase of glomerular filtration rate and renal plasma flow. Medullary concentration gradient of sodium also markedly lowered in the infused kidney. These changes were not observed during mannitol diuresis and renal action of dopamine were not apparent in dog pretreated with haloperidol. From the above experimental results, it is thought that dopamine, when given into a vien or infused directly into a renal artery, induces diuresis, and the mechanism of its action is due to dual actions which are hemodynamic effect along with glomerular filtraction rate, and the increased response in the medullary blood flow.

  • PDF

Mass transfer in adiabatic rectifier of ammonia-water absorption system (암모니아-물 흡수식 시스템에서 단열정류기의 물질 전달)

  • 김병주
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.11 no.3
    • /
    • pp.414-421
    • /
    • 1999
  • Falling film rectification involves simultaneous heat and mass transfer between vapor and liquid interface. In the present work, the adiabatic rectification process of ammonia-water vapor on the vertical plate was investigated. The continuity, momentum, energy and diffusion equations for the solution film and vapor mixture were formulated in integral forms and solved numerically. The model could predict the film thickness, the pressure gradient, and the mass transfer rate. The effects of Reynolds number and ammonia concentration of solution and vapor mixture, rectifier length, and the enhancement of mass transfer in each phases were investigated. The stripping of water in vapor mixture occurred new the entrance of ammonia solution, which imposed the proper size of an adiabatic rectifier. Rectifier efficiency increased as film Reynolds number increased and as vapor mixture Reynolds number decreased. The improvement of rectifier efficiency was significant with the enhancement of mass transfer in falling film.

  • PDF