• Title/Summary/Keyword: Life Ion

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Action of Dammarane-Type Triterpenoidal Glycosides and Their Aglycones on Lipid Membranes (지질막에 대한 Dammarane-Type Triterpenoidal Glycosides와 그 Aglycones의 작용)

  • Kim, Yu.A.;Park, Kyeong-Mee;Hyun, Hack-Chul;Song, Yong-Bum;Shin, Han-Jae;Park, Hwa-Jin
    • Journal of Ginseng Research
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    • v.20 no.3
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    • pp.269-273
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    • 1996
  • We investigated the effects of ginseng glycosides and their aglycones on processes of single ion channel formation and channel properties. The glycosides, Rg, and Rb, , and their aglycones, 20-(S)-protopanaxatriol (PT) and 20-(S)-protopanaxadiol (PD) increased the membrane permeability for ions. PT, PD, Rg1, and Rb1; at concentrations of 0.5, 3.0, 10.0 and 30.0 $\mu\textrm{g}$/ml respectively; Induced single ion channel fluctuations with the life times in the range of 0.1~1005 in open states and conductances from 5 to 30 pS in 1 M KCI. At high concentrations of these substances, rapid fluctuations of transmembrane ion current with amplitude from hundred pS to dozen nS were observed. Against other substances, ginsenoside Rbl began to increase the membrane conductance at concentration of about 60 $\mu\textrm{g}$/ml without fluctuation of single ion channel. Membranes treated with PT, PD, Rg1 and Rb1 are more permeable to K+, than to Cl while zero current membrane potentials with 10 gradients of KCI were 12, 16, 8, 25 mV respectively. Key words : Membrane conductance, single ion channel, ginsenosides.

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Fabrication of petroleum pitch/polymer composite binder for anode material in lithium-ion battery (리튬이온 배터리용 음극 합금/폴리머 복합체 바인더 패브릭)

  • Hyeon Taek Jeong
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.6
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    • pp.1191-1200
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    • 2023
  • The lithium ion battery has applied to various fields of energy storage systems such as electric vehicle and potable electronic devices in terms of high energy density and long-life cycle. Despite of various research on the electrode and electrolyte materials, there is a lack of research for investigating of the binding materials to replace polymer based binder. In this study, we have investigated petroleum pitch/polymer composite with various ratios between petroleum pitch and polymer in order to optimize the electrochemical and physical performance of the lithium-ion battery based on petroleum pitch/polymer composite binder. The electrochemical and physical performances of the petroleum pitch/polymer composite binder based lithium-ion battery were evaluated by using a charge/discharge test, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and universal testing machine (UTM). As a result, the petroleum pitch(MP-50)/polymer(PVDF) composite (5:5 wt % ratio) binder based lithium-ion battery showed 1.29 gf mm-1 of adhesion strength with 144 mAh g-1 of specific dis-charge capacity and 93.1 % of initial coulombic efficiency(ICE) value.

Development of High Density Mammalian CellCulture system for the Production of Tissue-Type Plasminogen Activator

  • Park, Byong-Gon;Chun, Joo-Mi;Lee, Chang-Jin;Chun, Gie-Taek;Kim, Ik-Hwan;Jeong, Yeon-Ho
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.2
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    • pp.123-129
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    • 2000
  • A high cell density culture system for the anchorage dependent CHO cells was developed based on the combination of in removal of ammonium ion and microcarrier culture system, and semi-fed-batch feeding of glucose and glutamine was employed to the developed culture system. The glass bead was selected as an optimum microcarrier in terms of cell growth. An ammonium ion selective zeolite, Phillipsite-Gismondine, was packed in a dialysis menium ion. The semi-fed-batch operation was employer to the novel culture system for the high density cell culture, and the results showed the cell growth was improved by 32% and tPA productivity by 250%.

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Nitrate Ion-Selective Membrane Electrode Based on Complex of Ammonia Modified Bakelite A-Ni(II) Nitrate (Bakelite A-Ni(II) 착물의 질산이온 선택성 막전극)

  • Kim, Hwan-Ki;Shin, Doo-Soon
    • Journal of the Korean Chemical Society
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    • v.31 no.3
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    • pp.271-279
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    • 1987
  • A nitrate ion-selective PVC membrane electrode based on ammonia modified bakelite A-Ni$(NO_3)_2$ complex as ion exchanger was prepared. The electrode gave a linear response with a Nernstian slope of 60mV per decade within the concentration range $1{\sim}10^{-4}$ M $KNO_3$ but nonresponse to hydrogen ion and multivalent anions. The selectivity, response time and life time of the electrode were investigated and it was found that the electrode exhibited good selectivity for four univalent anions ($Cl^-,\;Br^-,\;I^-,\;{ClO_4}^-$). Analytical application to the determination of nitrate were also studied.

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Nanostructured Electrode Materials for Rechargeable Lithium-Ion Batteries

  • Zhao, Wei;Choi, Woosung;Yoon, Won-Sub
    • Journal of Electrochemical Science and Technology
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    • v.11 no.3
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    • pp.195-219
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    • 2020
  • Today, rechargeable lithium-ion batteries are an essential portion of modern daily life. As a promising alternative to traditional energy storage systems, they possess various advantages. This review attempts to provide the reader with an indepth understanding of the working mechanisms, current technological progress, and scientific challenges for a wide variety of lithium-ion battery (LIB) electrode nanomaterials. Electrochemical thermodynamics and kinetics are the two main perspectives underlying our introduction, which aims to provide an informative foundation for the rational design of electrode materials. Moreover, both anode and cathode materials are clarified into several types, using some specific examples to demonstrate both their advantages and shortcomings, and some improvements are suggested as well. In addition, we summarize some recent research progress in the rational design and synthesis of nanostructured anode and cathode materials, together with their corresponding electrochemical performances. Based on all these discussions, potential directions for further development of LIBs are summarized and presented.

Conversion-Alloying Anode Materials for Na-ion Batteries: Recent Progress, Challenges, and Perspective for the Future

  • Kim, Joo-Hyung;Kim, Do Kyung
    • Journal of the Korean Ceramic Society
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    • v.55 no.4
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    • pp.307-324
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    • 2018
  • Rechargeable lithium-ion batteries (LIBs) have been rapidly expanding from IT based applications to uses in electric vehicles (EVs), smart grids, and energy storage systems (ESSs), all of which require low cost, high energy density and high power density. The increasing demand for LIBs has resulted in increasing price of the lithium source, which is a major obstacle to wider application. To date, the possible depletion of lithium resources has become relevant, giving rise to the interest in Na-ion batteries (NIBs) as promising alternatives to LIBs. A lot of transition metal compounds based on conversion-alloying reaction have been extensively investigated to meet the requirement for the anodes with high energy density and long life-time. In-depth understanding the electrochemical reaction mechanisms for the transition metal compounds makes it promising negative anode for NIBs and provides feasible strategy for low cost and large-scale energy storage system in the near future.

The performance and quality improvement of Lithium ion Batteries

  • Xiaoping Li
    • 한국전기화학회:학술대회논문집
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    • 2004.11a
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    • pp.75-108
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    • 2004
  • The market, development and trend of Lithium ion Batteries in China are introduce briefly. Early, Chinese manufactories were busy to expand and many new battery factories have been built up. Now, the relatively large companies pay more attentions on comprehensive quality improvement, therefore the production processing and facilities have been also modified in some extent. The recent technology progresses focus on High capacity (energy density), High rate, High average voltage, High safety, High temperature properties, Long cycle life, Low temperature properties, Low self discharge, Low cost, Super-large, Super-small, Super-thin, Consistency, Customization, and Environment friendly processing, simply $H_5L_4S_3C_2E_1$. Lithium ion polymer batteries which all batteries packaged with soft lamination film are named as in China have a quick growth and emphasized here because of their advantages ins $H_5L_4S_3C_2E_1$ for which it is quite difficult to be realized at the same time. Some of research works such as listed above are introduced. The other contends related to application trend of Lithium ion batteries and projects carrying out are also included.

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Intrinsic Gating in Inward Rectifier Potassium Channels (Kir2.1) with Low Polyamine Affinity Generated by Site Directed Mutagenesis

  • So, I.;Ashmole, I.;Soh, H.;Park, C.S.;Spencer, P.J.;Leyland, M.;Stanfield, P.R.
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.3
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    • pp.131-142
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    • 2003
  • We have studied mutant forms of Kir2.1 in which an aspartate residue (D172), important for gating by intracellular polyamines, is replaced by one of three basic residues (Arg, Lys or His). Such channels are highly selective for $K^+$, but show inward rectification that is a shallow function of voltage compared with that found in wild type. This inward rectification occurs with a reduced affinity for spermine and persists in the absence of polyamines. Though the unitary current-voltage relation shows some inward rectification, it is insufficient to account for that seen under whole cell recording. Channels open and shut under single channel recording, and changes of $P_{open}$ appear to generate inward rectification. In D172H, the reduction in affinity for spermine is greater when His is protonated at low $pH_i$. The effective valency for spermine is reduced from $3.09{\pm}0.07$ in wild type to $1.95{\pm}0.09$ in D172H at $pH_i$ 6.3. In the presence of dual mutants of Kir2.1, where E224 is also replaced, spermine affinity becomes undetectable. However, channels still show inward rectification and open and shut under hyper- and depolarisation, respectively. We suggest that Kir2.1 channel are able to undergo conformation changes; these changes may be important physiologically in generating inward rectification, the normal parameters of which are set by the binding of polyamines such as spermine.