• Analytical Science and Technology
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• v.8 no.1
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• pp.79-84
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• 1995

Ion-selective poly(vinyl chloride) membrane electrodes for the determination of the anticholinergic drug alverine in pure substances is described. Ion-pair complex of alverine with anionic counter ion acid red 97 is investigated as electroactive compound for the electrode membrane. On the optimal composition of membrane, its slope was 55.35mV/decade, relative standard deviation was 0.61 and lower limit of linear range was $1.0{\times}10^{-5}M$. The observed potentiometric selectivity coefficient was -2.625 toward methylephedrine and -2.216 toward histidine. We can got the stable potential at pH 7.0~4.0. Response time was 20~30 seconds for solutions${\leq}10^{-4}M$, about 10 seconds for solutions ${\geq}10^{-4}M$ of these compounds.

• Journal of the Korean Solar Energy Society
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• v.30 no.3
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• pp.90-97
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• 2010

$TiO_2$ thin films for solar energy utilization were prepared on ITO coated glass by r.f magnetron sputtering with variations of working pressure, oxygen flow rate and annealing temperature. Ion insertion and extraction reaction, and ion storage properties of films were investigated by using a cyclic voltammetry. Transmittance of thin films in as-prepared, colored and bleached states was measured by UV-VIS spectrophotometer. The samples deposited in our sputtering conditions showed poor electrochromic properties. Improvement in ion storage properties of $TiO_2$ thin film was observed after annealing at temperature of $400^{\circ}C$ in air for 2 hours. It was found that $TiO_2$ thin film in electrochromic device could be used as a passive counter-electrode.

• Carbon letters
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• v.12 no.3
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• pp.180-183
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• 2011

Li metal is accepted as a good counter electrode for electrochemical impedance spectroscopy (EIS) as the active material in Li-ion and Li-ion polymer batteries. We examined the existence of signal noise from a Li-metal counter quantitatively as a preliminary study. We suggest an electrochemical cell with one switchable electrode to obtain the exact impedance signal of active materials. To verify the effectiveness of the switchable electrode, EIS measurements of the solid electrolyte interphase (SEI) before severe $Li^+$ intercalation to SFG6 graphite (at > ca. 0.25 V vs. Li/$Li^+$) were taken. As a result, the EIS spectra without the signal of Li metal were obtained and analyzed successfully for the following parameters i) $Li^+$ conduction in the electrolyte, ii) the geometric resistance and constant phase element of the electrode (insensitive to the voltage), iii) the interfacial behavior of the SEI related to the $Li^+$ transfer and residence throughout the near-surface (sensitive to voltage), and iv) the term reflecting the differential limiting capacitance of $Li^+$ in the graphite lattice.

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.224-230
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• 1986

Dodecyltrimethylammonium bromide (DTAB) was examined as a counter-ion in the separation of aromatic sulfonic acids on alkylmodified silica (ODS) column by reversed-phase ion-pair chromatography. The capacity factor of acids was investigated and separation was attempted. The capacity factor of samples was influenced by the several factors such as a concentration of counter-ion, concentration of methanol, kinds and concentration of electrolyte in mobile phase as well as kinds and position of functional group in samples. Some mixtures of samples were able to be separated under optimum condition.

• Mass Spectrometry Letters
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• v.7 no.3
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• pp.64-68
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• 2016

Scanning electron microscopy combined with thermal ionization mass spectrometry (SEM-TIMS) was used to determine the precise isotope ratios of ultra-trace levels of uranium contained in individual microparticles. An advanced multiple ion counter system consisting of three secondary ion multipliers and two compact discrete dynodes was used for complete simultaneous ion detection. For verification purposes, using TIMS with complete simultaneous measurement, isotopes were analyzed in 5 pg of uranium of a certified reference material. A microprobe in the SEM was used to transfer individual particles from a NUSIMEP-7 sample to TIMS filaments, which were then subjected to SEM-TIMS and complete simultaneous measurement. The excellent agreement in the resulting uranium isotope ratios with the certified NUSIMEP-7 values shows the validity of SEM-TIMS with complete simultaneous measurement for the analysis of uranium isotopes in individual particles. Further experimental study required for investigation of simultaneous measurement using the advanced multiple ion counter system is presented.

• Journal of the Korean Chemical Society
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• v.37 no.9
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• pp.793-799
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• 1993

Ion-pair model was predominated over ion-interaction model in the retention mechanism of analytes when tetramethylammonium bromide (TMAB) was used as a counter-ion in the investigation of aromatic sulfonic acids on the reversed-phase liquid chromatography by $C_{18}$ column as a stationary phase. The capacity factors of analytes were influenced by the type and concentration of counter-ions, concentrations of methanol and co-anion, types and position of functional group, and the pH mobile phase. Components of analyte mixture could be separated under the optimum conditions by this method.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.313.2-313.2
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• 2002

Environmentally benign protein staining method in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) using both an acidic dye, zincon (ZC) and a basic dye. ethyl violet (EV) 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 produces bluish violet colored bands. It is a rapid procedure, involving only fixin and staining steps that are completed in 45 min. (omitted)

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.165-168
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• 2000

We fabricated ramp-edge Josephson junctions with barriers formed by interface treatments instead of epitaxially grown barrier layers. A low-dielectric Sr$_2$AlTaO$_6$(SAT) layer was used as an ion-milling mask as well as an insulating layer for the ramp-edge junctions. An ion-milled YBa$_2$Cu$_3$O$_{7-x}$ (YBCO)-edge surface was not exposed to solvent through all fabrication procedures. The barriers were produced by structural modification at the edge of the YBCO base electrode using high energy ion-beam treatment prior to deposition of the YBCO counter electrode. We investigated the effects of high energy ion-beam treatment, annealing, and counter electrode deposition temperature on the characteristics of the interface-controlled Josephson junctions. The junction parameters such as T$_c$, I$_c$c, R$_n$ were measured and discussed in relation to the barrier layer depending on the process parameters.

• Membrane Journal
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• v.5 no.4
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• pp.129-136
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• 1995

This study is concerned with the treatment of dye wastewater by carrier meditated emulsion liquid membrane. Optimum conditions for the removal of anionic dye and cationic dye by the emulsion liquid membrane(ELM) containing Aliquat 336 or D2EHPA were obtained in the batch operation, an actual dye wastewater was tested under these conditions. Dye reagents used were Sirius Red(Direct dye), Reactofix Supra Blue(Reactive dye), and Apollo Blue(Basic dye). The experimental variables were surfactant(Span 80) and carrier(Aliquat 336 or D2EHPA) concentration in the membrane phase, the counter ion($Na_2SO_4$) concentration in the internal phase and the amount of emulsion. Extraction equilibrium arrived within 5 minutes after starting reaction and more than 95% of dye ion could be removed. The carrier concentration in the membrane phase was the most crucial for the removal efficiency, but other variables effected to the reaction time more than the removal efficiency. The dye wastewater was treated under the optimum conditions in two steps. The absorbance at 550nm of wastewater was decreased 0.53 to below 0.03 after 10 minutes treatment.

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.312-319
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• 1986

Dodecyltrimethylammonium bromide (DTAB) was examined as a counter-ion in the investigation of capacity factor and separation of aromatic carboxylic acids on alkyl-modified silica (ODS) column as a stationary phase by ion-pair chromatography on reversed-phase system. The capacity factor of samples was influenced by the several factors such as a concentration of counter-ion as well as kinds and concentration of electrolyte, concentration of methanol in mobile phase and kinds and position of functional group in sample molecule. Some mixtures of samples were able to be separated under optimum condition.