• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1439-1444
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• 2006

A $Cu^{2+}$ ion-selective membrane microelectrode has been fabricated from poly vinyl chloride (PVC) matrix membrane containing a new symmetrical hexadentate Schiff,s base 2-{1-(E)-2-((Z)-2-{(E)-2-[(Z)-1-(2-hydroxyphenyl)ethylidene]hydrazono}-1-methylpropylidene)hydrazono]ethyl}phenol (HDNOS) as a neutral carrier, Potassium tetrakis(4-chlorophenyl) borate (KTpClPB) as an anionic excluder and o-nitrophenyloctyl ether (NPOE) as a plasticizing solvent mediator. The microelectrode displays linear potential response in the concentration range of $1.0\;{\times}\;10^{-5}-1.0\;{\times}\;10^{-11}$ M of $Cu^{2+}$. The microelectrode exhibits a nice Nernstian slope of 25.9 ${\pm}$ 0.3 mV $decade^{-1}$ in the pH range of 3.1-8.1. The sensor has a relatively short response time in whole concentration ranges ($\sim$5 s). The detection limit of proposed sensor is $5.0\;{\times}\;10^{-12}$ M (320 pg/L), and it can be used over a period of eight weeks. The practical utility of the sensor has been demonstrated by using it as an indicator electrode in the potentiometric titration of $Cu^{2+}$ with EDTA. The proposed membrane electrode was used for the direct determining of $Cu^{2+}$ content in black and red pepper, and in waste water samples.

• 한국화재소방학회논문지
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• 제29권4호
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• pp.61-66
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• 2015

건축물 내에 노출배관의 자재에 대한 별도의 규정을 두지 않음에 따라 내부식성, 내약품성 측면에서 우수하다고 알려진 Poly Vinyl Chloride (PVC)관을 많이 사용하고 있다. 그러나 화재시 유독가스의 발생과 화재의 확산 방지에 취약하다는 우려의 시각이 있다. 노출배관은 불연재를 사용하여야 화재시 유독가스의 확산을 방지하면서 인명이나 재산상의 피해를 최소화할 수 있다. 초대형 건축물이 많이 건설되고 있는 시기에 화재시 피해의 심각성이 매우 우려된다. 건축물의 화재안전기준을 강화하고, 높아진 안전의식을 수용하여야 선진국으로의 진입에 한걸음 더 나아갈 수 있다. 노출배관에 사용되는 자재를 조사하고, 선진국의 기준에 대해 분석하여 효율성을 연구함으로서 국민안전을 증대시킬 수 있다. 국내 각 지역별 건축물의 노출배관에 대해 현장의 실태를 조사하여 대안을 모색하고자 한다. 건축물 안전과 거주자의 안전 확보 및 국내 외 노출배관의 불연재 사용에 대한 실태를 바탕으로 관련법규를 개선함으로 국민안전에 대하여 그 효율성을 제고한다.

• 약학회지
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• 제40권2호
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• pp.135-140
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• 1996

Ion-selective poly(vinyl chloride)(PVC) membrane electrodes for the determination of the calcium antagonist verapamil and its pharmaceutical preparations were described. Verapam il-superchrome garnet Y(SGY), lumogallion(LG), acid red 97(AR97), Dragendorff(DD) and Meyer reagent ion pairs were inverstigated as an electroactive compound for membrane electrode. Stable potentiometric response was obtained with azo dye at pH 6.5-4.0 and with DD, and Meyer reagent at pH 6.5-3.0. The best plasticizer was 49w/w% 2-nitrophenyl octyl ether for azo dye, and 65.3w/w% tri(n-butyl) citrate for DD and Meyer reagent. Potentiometric response slopes of optimized membrane electrodes based on SGY, LG, AR97, DD, and Meyer complex for verapamil were 52.49, 54.88, 50.81, 54.13 and 49.31 mV/dec., respectively. Lower limits of linear range were $1.0{\times}10^6M$ for SGY, LG, and AR97, while those for DD and Meyer reagent were $4{\times}10^{-6}M$. Detection limits for all these electrodes were $1{\times}10^{-5}M,\;4{\times}10^{-6}M,\;1.8{\times}10^{-6}M,\;8{\times}10^{-7}M,\;and\;1{\times}10^{-6}M$ with relative standard deviation of 2.56, 3.6, 3.96, 2.56, 3.20%, respectively.

• 분석과학
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• 제14권1호
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• pp.59-63
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• 2001

철-디피리딜-메페남산 삼원착물을 이온교환체로, NPOE(o-nitrophenyl octyl ether)를 가소게, PVC[poly(vinyl chloride)]를 지지체로 사용한 메페남산 이온선택성막 전극을 제작하였다. 디피리딜 화합물은 2,2'-디피리딜, 4,4'-디피리딜 그리고 4,4'-디페닐-2,2'-디피리딜을 이용하였다. 이들 막전극은 pH 8.9의 붕산완충액 중에서 $10^{-5}{\sim}10^{-3}mol/L$ 농도의 메페남산에 대하여 감응전위가 -55.98, -49.47 그리고 -59.35mV/decade를 각각 나타내는 직선성이었다. 방향족 및 지방족 카복실산염의 존재는 전극의 감응에 지장을 주지 않았다.

• Journal of the Korean Wood Science and Technology
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• 제44권4호
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• pp.600-606
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• 2016

Wood-based composite panels such as plywood, particleboard (PB), or medium density fiberboard (MDF) are mostly used in the lamination on their surface for the manufacturing of furniture, or interior building products, the concern on the formaldehyde emission (FE) from the surface laminated wood panels is increasingly attracting attentions from the public. Thus, this study was conducted to understand influence of surface laminating materials to the FE from PB and MDF with or without edge sealing, using 24-hour desiccator method. Both PB samples that had been laminated on their surface with low-pressure laminate (LPL) or polypropylene (PP) film and MDF that had been treated with poly(vinyl chloride) (PVC) or coating were tested for the FE with or without edge sealing. As expected, the FE of PB with the sealed edges decreased to 37.4% and 80.7% with the LPL and PP lamination, respectively. The surface laminated MDF with the sealed edges also showed a decrease in the emission up to 57.8% and 54.3%, with the PVC lamination and coating, respectively. However, the coated MDF samples showed 5.3% increase in the emission when their edges were not sealed, indicating a FE form the solvent used for coating. These results showed that the type of surface lamination materials on wood-based composite panels has a great impact on their resultant FE, indicating that the influence of surface laminating materials should be taken into consideration for the formaldehyde mission measurement.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2303-2308
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• 2009

A thiocyanate poly(vinyl chloride) (PVC) membrane electrode based on [1,2-bis(diphenylphosphino)ethane]dihalopalladium( II), [(dppe)$PdX_2$, X = Cl ($L^1$), X = I ($L^2$)] as active sensor has been developed. The diiodopalladium complex, [(dppe)$PdI_2](L^2$) displays an anti-Hofmeister selectivity sequence: $SCN^-\;>\;I^-\;>\;{ClO_4}^-\;>\;Sal^-\;>\;Br^-\;>\;{NO_2}^-\;>\;{HPO_4}^-\;>\;AcO^-\;>\;{NO_3}^-\;>\;{H_2PO_4}^-\;>\;{CO_3}^{2-}$. The electrode exhibits a Nernstian response (-59.8 mV/decade) over a wide linear concentration range of thiocyanate ($(1.0\;{\times}\;10^{-1}\;to\;5.0\;{\times}\;10^{-6}$ M), low detection limit ($(1.1\;{\times}\;10^{-6}$ M), fast response $(t_{90%}$ = 24 s), and applicability over a wide pH range (3.5∼11). Addition of anionic sites, potassium tetrakis[p-chlorophenyl] borate (KTpClPB) is shown to improve potentiometric anion selectivity, suggesting that the palladium complex may operate as a partially charged carrier-type ionophore within the polymer membrane phase. The reaction mechanism is discussed with respect to UV-Vis and IR spectroscopy. Application of the electrode to the potentiometric titration of thiocyanate ion with silver nitrate is reported.

• 대한화학회지
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• 제37권8호
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• pp.773-778
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• 1993

Tl$^+$이온 센서로서 크라운 에테르 B15C5와 DB18C6를 중성운반체로 한 PVC 액체막 이온 선택성 전극을 제작하였다. 막용매로는 DOA, NPPE 및 NPOE를 사용하였으며 친유성 염, KTClPB의 농도를 변화시킨 여러가지 조성의 막을 시험하였다. B15C5와 DB18C6 막 전극의 감응전위는 농도범위, 10$^{-1}$∼10$^{-5}$M에서 직선으로 나타났으며 최대 기울기는 전극에 따라서 40∼55 mV/decade였다. 선택계수는 분리용액법으로 결정하였으며 알카리금속 이온, 알칼리토금속 이온 및 일부 전이금속 이온에 대하여 좋은 선택성을 나타냈다. 제작된 액체막 전극은 Ph > 3 에서 안정한 감응전위를 보였다.

• 한국재료학회지
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• 제26권4호
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• pp.173-181
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• 2016

In order to use coal tar pitch (CTP) as a raw material for carbon fibers, it should have suitable properties such as a narrow range of softening point, suitable viscosity and uniform optical properties. In this study, raw CTP was modified by heat treatment with three types of polymer additives (PS, PET, and PVC) to make a spinnable pitch for carbon fibers. The yield, softening point, C/H ratio, insoluble yield, and meso-phase content of various modified CTPs with polymer additives were analyzed by changing the type of polymer additive and the heat treatment temperature. The purpose of this study was to compare the properties of CTPs modified by polymer addition with those of a commercial CTP. After the pitch spinning, the obtained green fibers were stabilized and carbonized. The properties of the respective fibers were analyzed to compare their uniformity, diameter change, and mechanical properties. Among three polymer additives, PS220 and PET261 pitches were found to be spinnable, but the carbon fibers from PET261 showed mechanical properties comparable with those of a commercial CTP produced by an air-blowing method (OCI284). The CTPs modified with polymer additive had higher ${\beta}$-resin fractions than the CTP with only thermal treatment indicating a beneficial effect of carbon fiber application.

• 공업화학
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• 제2권2호
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• pp.175-184
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• 1991

PVC 와 Polystyren 과 같은 고분자가 자외선에 노출될 때 이들 표면을 보호하고, 물성을 유지하기 위해서 자외선 경화 도료를 도장하지만, PVC 는 epoxy acrylate 에 대해서, 그리고 Polystyren 은 대부분의 UV도료에 부착력이 약하므로, 반응희석제의 조성을 변화시키거나, 다관능기 acrylate를 표면에 photografting 시키거나, 표면을 광화학적으로 활성화시켜 부착력을 향상시킴을 목적으로 하였다. 미리 침투시킨 광개시제에 의한 grafting이나 표면 활성화로 부착력은 현저히 증가하였고, 각 희석제에 있어 Tripropylene glycol diacrylate는 유연성 향상과 부착력 증가를 가져오나, 황변 현상과 표면 산화에 의한 경화 밀도의 증가로 grafting을 제외한 다른 도장 방법은 시간이 지남에 따라 도막의 부착력이 감소하였다. 여기에 비해 Trimethylol propane triacrylate 는 원래 다관능기에 의해 높은 경화 밀도를 가지고 이에 따른 단단한 도막 때문에 부착력에 문제가 있으나, 두가지 도장법에서는 오히려 다관능기에 의한 화학 결합으로 부착력이 향상되었다. 그리고, 고분자 표면의 표면 에너지를 활성화를 통해 증가시킴으로 해서 UV 도료의 상용성 문제를 grafting 과 표면 활성화를 통해 해결해 도료 배합의 다양화와 기능화를 가져올 것이 기대된다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권2호
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• pp.150-158
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• 2011

Present study aims to investigate the influence of relative breakwater width W/L (W=width of breakwater, L=wavelength), wave steepness $H_i/gT^2$ (Hi=incident wave height, T=wave period) and relative wave height d/W (d=water depth) on forces in the moorings of horizontal interlaced multi-layered moored floating pipe breakwater (HIMMFPB) model. Studies were conducted on scaled down physical models having three layers of Poly Vinyl Chloride (PVC) pipes, wave steepness $H_i/gT^2$ varying from 0.063 to 0.849, relative width W/L varying from 0.4 to 2.65 and relative spacing S/D=2 (S=horizontal centre-to-centre spacing of pipes, D=diameter of pipes). Peak mooring forces were also measured and data collected is analyzed by plotting non-dimensional graphs depicting variation of $f_s/{\gamma}W^2$ ($f_s$=Sea side Mooring force, ${\gamma}$=specific weight of water) & $f_l/{\gamma}W^2$ ($f_l$=Lee side Mooring force) with $H_i/gT^2$ for d/W varying from 0.082 to 0.276 and also variation of $f_s/{\gamma}W^2$ and $f_l/{\gamma}W^2$ with W/L for $H_i$/d varying from 0.06 to 0.400.