• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1465-1470
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• 2004

A short and efficient synthesis, solvent extraction and potentiometric measurements of new thiazole-containing naphtho-crown ethers are reported. The naphthalene moiety enhances the ammonium ion selectivity over potassium ion. The selectivity of ${NH_4}^+/K^+$ follows the trend $3\;{\approx}\;2\;>\;1$, indicating that the differences in conformational changes of 2 and 3 in forming ammonium complexes affect little on the resulting ammonium/potassium extraction selectivity ratio. The ammonium ion-selective electrodes were prepared with noctylphenyl ether plasticized poly(vinyl chloride) membranes containing 1-4 the effect of one naphthalene unit introduced on either right (2) or left (3) side of thiazolo-crown ether on their potentiometric properties (e.g., ammonium ion selectivity over other cations, response slopes, and detection limits) were not apparent. However, the ammonium ion selectivity of 1, 2 and 3 over other alkali metal and alkaline earth metal cations is 10-100 times higher than that of nonactin.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.476-476
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• 2004

• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2722-2726
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• 2011

Plasticized poly(vinyl chloride), PVCs, with different membrane compositions tested for use in the construction of an ion-selective sensor for the determination dibucaine. A prepared membrane with dioctyl phthalate-PVC and ion-pair of N-(1-naphthyl)ethylenediamine dihydrochloride-tetraphenyl borate had a good potential to acts as a potentiometric sensor for the analysis of dibucaine. A linear relationship was obtained between potential and logC varying between $1.0{\times}10^{-6}$ and $1.0{\times}10^{-2}$ M dibucaine with a good repeatability and reproducibility. The sensor was applied for the determination of the drug in pharmaceuticals and biological fluids such as plasma and urine samples with satisfactory results. The drug electrode has also been used to study the interaction of bovine serum albumin (BSA) with dibucaine. The saturated quantities of dibucaine binding were 13.04, 5.30 and 9.70 mol/mol in 0.01, 0.02 and 0.1% of protein, respectively.

• Journal of Biosystems Engineering
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• 제28권4호
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• pp.335-342
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• 2003

A simple disposable thick-film potentiometric strip has been developed and evaluated for hydroponics application. The strip consisted of low ion-selective electrodes (ISE) fabricated by screen-printing technology. The electrochemical responses of ion sensors for nitrate, ammonium, potassium, and magnesium were measured with specially designed 16-channel low voltage signal transducers. The analytical characteristics of the sensors were comparable with those of conventional ISE sensors. The thick-film sensors exhibit linear relationships over five concentration decades. The concentration of N $O_3$ - ion in standard solution can be determined by direct potentiometric measurements without any conditioning before measurements. However, measurement of $K^{+}$, N $H_4$$^{+}$, and $Mg^{2+}$ ionic concentrations in nutrient solutions seems not feasible.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.421-425
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• 2003

A new thallium(Ⅰ) selective electrode based on dibenzylidaza-18-crown-6 as mambrane carrier was successfully prpared. The electrode exhibitis a near-Nernstian response for $ T1^+$ ions over a wide concentration range from $1.0×10^{15}-1.0×10^{-1}$M at 25℃, and was found to be selective, precise and useable within the pH range 4.0-11.0. The electrode was successfully used as an indicator electrode in potentiometric titration of thallium ions.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.800-804
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• 2011

A potentiometric sensor based on the Schiff base $(N^2E,N^{2'}E)-N^2,N^{2'}$-bis(thiophen-2-ylmethylene)-1,1'-binaphthl-2,2'-diamine has been synthesized and explored as an ionophore PVC-based membrane sensor selective for the silver ($Ag^+$) ion. Potentiometric investigations indicate a high affinity of this receptor for the silver ion. Seven membranes have been fabricated with different compositions, with the best performance shown by the membrane with an ionophore composition (w/w) of: 1.0 mg, PVC: 33.0 mg, DOA: 66.0 mg in 1.0 mL THF. The sensor worked well within a wide concentration range of $1.0{\times}10^{-2}$ to $1.0{\times}10^{-7}$ M, at pH 5, at room temperature (slope 57.4 mV/dec.), and with a rapid response time of 9 s; the sensor also showed good selectivity towards the silver ion over a huge number of interfering cations, with the highest selectivity coefficient for $Hg^{2+}$ at -3.7. Thus far, the best lower detection limit was $4.0{\times}10^{-8}$ M.

• 공업화학
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• 제32권4호
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• pp.456-460
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• 2021

본 연구에서는 탄소 및 은 잉크를 사용하여 스크린 인쇄 공정을 통한 전위차 나트륨 이온(Na⁺) 센서를 제작하였다. 센서의 두 전극 구성은 Na⁺ 용액에서 네른스트 거동에 따라 전극의 전위차를 발생하였다. 제조된 Na⁺ 센서는 이상적인 네른스트 민감도, 빠른 응답 시간 및 낮은 검출 한계를 보여주었다. 네른스트 반응은 센서의 반복성 및 장기 내구성 테스트 시 안정적이었다. 탄소 전극에 코팅된 Na⁺ 선택막은 간섭 이온에 대해 나트륨 이온을 선택적으로 통과시켜 우수한 선택성을 증명하였다. 휴대용 Na⁺ 센서는 인쇄 회로 시스템을 사용하여 제작되었으며 다양한 실제 샘플에서 Na⁺ 농도를 성공적으로 측정하는 것을 증명하였다.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1738-1742
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• 2005

In this study a novel triiodide ion-selective electrode based on a charge transfer complex of iodine and Bis(2-hydroxyacetophenone)butane-2,3-dihydrazone (ICT), as a membrane carrier was prepared. The electrode has a linear dynamic range between 1.0 ${\times}$ $10^{-2}$ and 5.0 ${\times}$ $10^{-7}$ M, with a Nernstian slope of 58. 99 ${\pm}$ 0.3 mV $decade^{-1}$ and detection limit of 3.0 ${\times}$ $10 ^{-7}$ M. The potentiometric response of the proposed sensor is independent of the pH of the solution in the pH range of 3.0-10.0. The electrode possesses the advantages of short conditioning time, fast response time, and especially, very good selectivity over a large number of common organic and inorganic anions. The electrode can be used for at least 6 months without any considerable divergences in the potentials. It was used as an indicator electrode in potentiometric titration of triiodide ion with thiosulfate.

• Journal of Biosystems Engineering
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• 제32권5호
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• pp.348-353
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• 2007

A solid state ion sensor module has been developed and evaluated for hydroponic nutrients analysis. The sensor module consisted of five ion-selective electrodes (ISE) fabricated by screen-printing technology. The electrochemical responses of ion sensors for nitrate, ammonium, potassium, calcium, and pH were measured with specially designed 7-channel low voltage signal transducers. The analytical characteristics of the sensors were comparable with those of conventional ISE sensors. The solid state ion sensors exhibit linear relationships over five concentration decades. Detection limit of the sensors were $5.6{\times}10^{-5}{\sim}1.6{\times}10^{-7}M$ depends on ions. Performance test results showed that relative errors of measured ion concentrations were less than 5% for $NO_3{^-},\;K^+,\;Ca^{2+}$ ion, and pH. The concentration of $NO_3{^-},\;NH_4{^+},\;K^+,\;Ca^{2+}$, and pH ion in standard solution and nutrient solutions could be determined by direct potentiometric measurements without any conditioning before measurements.

• 센서학회지
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• 제14권4호
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• pp.258-264
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• 2005

Li+-ion conducting ($Li_{3}PO_{4}$) thin films with thickness of $0.3{\mu}m$, $0.65{\mu}$, $1.2{\mu}$ were deposited on $Al_{2}O_{3}$ substrate at room temperature by thermal evaporation. They were sintered at $700^{\circ}C$ and $800^{\circ}C$ for 2 hours, respectively. Reference electrode and sensing electrode were printed on Au-electrode by silk printing method. The EMF and the ${\Delta}EMF$/dec were increased with increasing the electrolyte thickness and sintering temperature. The sample sintered at $800^{\circ}C$ was shown a good response and recovery characteristics more than those sintered at $700^{\circ}C$. The Nernst's slop of 75 mV per decade was obtained at operating temperature of $500^{\circ}C$.