• The Korean Journal of Ceramics
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• 제7권1호
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• pp.1-5
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• 2001

Inorganic-organic hybrid Li$^+$ ion conductors were prepared by the sol-gel process. Tetramethyl orthosilicate (TMOS), polyethylene glycol 200 (PEG$_200$) and lithium bis (trifluoro-methylsulfony) imide were used as raw materials and $H_2O$ was used as a solvent. Hybrid Li$^+$ ion conductor prepared by the sol-gel process showed very high ion conductivities of log${\sigma}_R.T$(S/cm)=-3.73, log${\sigma}_60$(S/cm)=-3.00 at room temperature and $60^{\circ}C$, respectivery. Decomposition voltage was 3.1 V.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.69.3-69.3
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• 2012

A high-performance low-voltage graphene field-effect transistor (FED array was fabricated on a flexible polymer substrate using solution-processable, high-capacitance ion gel gate dielectrics. The high capacitance of the ion gel, which originated from the formation of an electric double layer under the application of a gate voltage, yielded a high on-current and low voltage operation below 3 V. The graphene FETs fabricated on the plastic substrates showed a hole and electron mobility of 203 and 91 $cm^2/Vs$, respectively, at a drain bias of - I V. Moreover, ion gel gated graphene FETs on the plastic substrates exhibited remarkably good mechanical flexibility. This method represents a significant step in the application of graphene to flexible and stretchable electronics.

• 한국응용과학기술학회지
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• 제25권1호
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• pp.65-72
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• 2008

The ion exchangers supported on silica gel containing primary, secondary, or tertiary amine groups show a behaviour that is weakly acidic, while the quaternary salts are strongly acidic. These properties change according to the hydrophilicities of the modifier functional groups. Ammonium salt derivatives supported on silica gel were prepared from silica modified with 3-Aminopropyltriethoxysiliane and N-3-(Trimethoxysilyl)propylehtylene diamine. The preparation and the ion exchange properties of two systems were discussed. Two systems have different hydrophilicities and contain ammonium chloride derivatives of 3-amminopropyltriethoxysilane and N-3-(triehtoxysilyl)propyl ethylene diamine supported on silica gel, $SA^+/Cl^-$ and $SA^+/Cl^-$, respectively. The high affinity to perchlorate ion presented by the $SA^+/Cl^-$ through the equilibrium studies of ion exchange led us to its application as an ion selective electrode for the perchlorate ion. The determination of the perchlorate ion in the presence of other anions and in complexes is very difficult. Few analytical methods are available and most of them are indirect. Both materials showed potential use as an ion exchanger; they are thermically stable, achieve equilibrium rapidly in the presence of suitable exchanger ions, and are easily recovered.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2003년도 추계학술대회
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• pp.351-357
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• 2003

The optimum polymer gel electrolyte composition ratio was 23 : 66 : 11 wt% of P(VdF-co-HFP) : PVP =20 : 3), (PC: EC =44 : 22) and TEABF$_4$. And the optimal thickness of polymer gel electrolyte was 50 ${\mu}{\textrm}{m}$. The electrochemical characteristics result of unit cell were 31.41 Fig of specific capacitance, and 3.21$\times$10$^{-3}$ S/cm of ion conductivity. Ion conductivity of polymer gel electrolytes decreased according to added PVP through impedance analysis, and it was higher in 7 wt%, but electrochemical characteristics of unit cell were better in 3 wt% PVP. And for excellent ion conductivity of polymer gel electrolytes, the use of a thin layer electrolyte(20 $\mu\textrm{m}$) was an effective method, but with unit cell application, the best thickness was 50 $\mu\textrm{m}$. Unit cell showed higher capacitance and more stable electrochemical performance when hot pressed between polymer gel electrolyte and electrode. This results from enhancement of the physical contact between the electrode and the polymer gel electrolyte and good accessibility of the liquid electrolyte to the electrode surface.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.704-708
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• 2002

A fast and sensitive protein staining method in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) using both an acidic dye, Coomassie Brilliant Blue R-250 (CBBR) and a basic dye, Neutral Red (NR) is described. It is based on a counter ion-dye staining technique that employs oppositely charged two dyes to form an ion-pair complex. The selective binding of the free dye molecules to proteins in an acidic solution enhances the staining effect of CBBR on protein bands, and also reduces gel background. It is a rapid staining procedure, involving fixing and staining steps with short destaining that are completed in about 1 h. As the result, it showed two to fourfold increase in sensitivity comparing with CBBR staining. The stained protein bands can be visualized at the same time of staining.

• 폴리머
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• 제27권4호
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• pp.385-391
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• 2003

본 연구에서는 에틸렌 옥사이드의 반복 단위 길이 (n＝3, 7.3, 11.8, 그리고 16.3)가 다른 리튬 p-［메톡시 올리고(에틸렌옥시)］벤젠설폰산염 (LiEOnBS)을 합성하였다. 이 전해질 염을 이용하여 고분자 전해질을 제조하였으며, 에틸렌 옥사이드의 반복 단위 길이 및 농도에 따른 이온 전도도 그리고 리튬 이온의 운반율에 대해 조사하였다. 고분자 전해질의 이온 전도도는 3$0^{\circ}C$에서 4.89$\times$$10^{-4}$ S/cm (LiEO7.3BS, 0.5 M)로 최고 이온 전도도를 보였다. Dc분극과 ac 임피던스를 혼합하여 측정한 고분자 전해질의 리튬 이온의 운반율은 0.75~0.92 이였으며, 농도가 증가할수록 리튬 이온 운반율은 감소하였다. LiEO7.3BS의 전해질 염을 0.1 M로 사용한 고분자 전해질인 경우 0.92로 최고의 리튬 이온 운반율을 보였다. 이로부터 벤젠설포네이트에 치환된 에틸렌 옥사이드의 반복 단위가 3이상만 되어도 높은 리튬 이온 운반율을 가지는 단일 이온 전해질 특성을 보임을 알 수 있었다.

• The Korean Journal of Ceramics
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• 제2권1호
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• pp.48-53
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• 1996

Ion beam assisted crystallization behavior of sol-gel derived $PbTiO_3$ thin films, deposited on bare silicon(100) substrates by spin-casting method, has been investigated. Ar ion bombardment was directly conducted on the spincoated film surface with or without heating the film from room temperature to $300^{\circ}C$. Ion dose was changed from $5{\times}10^{15}$ to $7.5{\times}10^{16}$ $Ar^-/cm^2$. Formation of (110) oriented perovskite phase was obseerved with ion dose above $5{\times}10^{16}\; Ar^+/cm^2$. Crystallization of $PbTiO_3$ thin film could be enhanced with increasing the Air ion dose, or heating the substrate during ion bombardment. Crystallization of the $PbTiO_3$ films by ion bombardment was related to the local heating effect during ion bombardment.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.252-254
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• 2002

In this study, polyurethane acrylate macromer was synthesized and it was used in a gel polymer electrolyte, and then its electrochemical performances were evaluated. LiCoO$_2$/GPE/MCF cells were also prepared and their performances depending on discharge currents and temperatures were evaluated. ionic conductivity of the gel polymer electrolyte with PUA at room temperature and -20$^{\circ}C$ was ca. 4.5 x 10$\^$-3/ S/cm and 1.7${\times}$10$\^$-3/ S/cm, respectively. GPE was stable electrochemically up to 4.5 V vs. Li/Li$\^$+/. LiCoO$_2$/GPE/MCF cell showed a good high-rate and a low-temperature performance.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.319-322
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• 2009

Gel polymer electrolytes were prepared by immersing a porous poly(vinylidene fluoride-co-hexafluoropropylene) membrane in an electrolyte solution containing small amounts of polymerizable additive (3,4-ethylenedioxythiophene, thiophene, biphenyl). The organic additives were electrochemically oxidized to form conductive polymer films on the electrode at high potential. With the gel polymer electrolytes containing different organic additive, lithium-ion polymer cells composed of carbon anode and LiCo$O_2$ cathode were assembled and their cycling performances were evaluated. Adding small amounts of thiophene or 3,4-ethylenedioxythiophene to the gel polymer electrolyte was found to reduce the charge transfer resistance in the cell and it thus exhibited less capacity fading and better high rate performance.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.343-347
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• 2005

The polysaccharides were extracted from fruiting body, mycelia, and cell-free broth of Agaricus blazei Murill. The crude polysaccharides were obtained by the ethanol addtion. They were further purified using ion-exchange chromatography and gel chromatography. Ion-exchange chromatography using DEAE-cellulose column separated neutral and acidic polysaccharides. Neutral polysaccharides were then purified with gel filtration chromatography. For single peak obtained from gel filtration chromatography was molecular weight was measured with Sepharose CL-6B. The same procedure with acidic polysaccharides were performed to get the purified polysaccharides.