• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.41-44
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• 2009

Photonic crystals containing multiple rugate structure are prepared by electrochemical etchings. Typically etched rugate PSi prepared in this study. Etching is carried out in a Teflon cell by using a two-electrode configuration with a Pt mesh counter electrode. They exhibit sharp photonic band gaps in the optical reflectivity spectrum. This reflectivity can be tuned to appear anywhere in the visible to near-infrared spectral range, depending on the programmed etch waveform. We study the method of full width half maxima and reflectivity index control by using amplitude.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.2
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• pp.67-76
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• 1986

It is observed that an appreciable short-circuit current (Is) flows by the time variation of temperature without applying external field in M1(metal)-P(polymer)-M2(metal)system. In M1-P-M2(A1) system, Is flows in the direction from the electrode(A1) having a lower workfunction to the counter electrode(M1) during heating and its magnitude increases as the thickness of polymer is decreased and as the heating rate is raised. The sign of Is is reversed in lower temperature region (under glass transition temperature) when the direction of temerature variation is changed during heating and cooling. From these experimental results, we can sugest that Is flows in the external short-circuit during the space charge distribution formed around both interfacial surfaces (M1-P and P-M2) is continuously maintained in the non-equilibrium state but not in equilibrium state.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.139-145
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• 2013

The electrochemical analysis of silver ion was performed using cyclic voltammetry (CV) and square-wave (SW) stripping voltammetry, and electrode cell systems were fabricated with graphite pencil electrode (GE) of working, reference and counter electrodes. Also electrolyte was the use of sea water as electrolyte solutions instead of ionic controlled solutions. The optimum analytical conditions for the cyclic and stripping parameters were determined using GE. The results approached the microgram working ranges of SW(ug/L) and CV(ug/L) Ag, and the optimum conditions were applied to frog's tissue and the food samples.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.29-33
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• 2001

A method for the determination of anionic drug, mefenamate with ion-selective electrode using Fe(II)-1,10-phenanthroline chelate as a counter ion was developed. Benzyl nitrophenyl ether (BNPE) plasticized membrane was more selective and sensitive than the other tested membranes. This membrane electrode exhibits a linear response for 10$^{-2}$ M~5 $\times$ 10$^{-5}$ M of mefenamic acid with a slope of -61.4 mV/dec. in borate buffer solutions (pH 9.0). Potentiometric selectivity measurements revealed negligible interferences from various organic and ionorganic anions. Direct potentiometry and potentiometric titration method of mefenamic acid in capsule preparations are presented and compared.

• YAKHAK HOEJI
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• v.46 no.5
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• pp.320-323
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• 2002

A method for the determination of acidic drug, mefenamic acid and ibuprofen with ion-selective electrode(ISE) using Fe(II)-di-2-pyridyl ketone oxime complex as a counter ion were developed. Benzyl-2-nitrophenyl ether(BNPE) plasticized membrane was more selective and sensitive than the other tested membranes. The acidic drug selective electrode exhibits a linear response for 10$^{-2}$ M 510$^{-5}$ M of acidic drugs, mefenamic acid and ibuprofen with a slope of -55.9 and -56.3 mV/dec. in borate buffer solution (pH 8.9). Potentiometric selectivity measurements revealed negligible interferences from aromatic and aliphatic carboxylic acid salts. The electrodes were found to be useful for the direct determination of mefenamic acid and ibuprofen in pharmaceutical preparations.

• Journal of Information Display
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• v.12 no.2
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• pp.97-99
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• 2011

We report flexible, bistable cholesteric displays utilizing polyester (PET) substrates with printed internal black electrodes. The black electrodes consist of carbon ink dispersed in butyl carbitol using a patented roll-to-roll gravure-offset printing. A transparent conducting polymer printed on PET serves as the counter electrode. The electro-optic material is a chiral nematic mixture dispersed in a low-concentration polymer binder. The device can be switched between scattering (black) and reflective (vibrant green) states upon application of an electric pulse. The internal black electrode enhances the contrast of the display and simplifies the roll-to-roll manufacture of flexible displays.

• Transactions on Electrical and Electronic Materials
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• v.14 no.2
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• pp.86-89
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• 2013

Dye-sensitized solar cells have a FTO/$TiO_2$/Dye/Electrode/Pt counter electrode structure, yet more than a 10% electron loss occurs at each interface. A passivating layer between the $TiO_2$/FTO glass interface can prevent this loss of electrons. In theory, ZnO has excellent electron collecting capabilities and a 3.4 eV band gap, which suppresses electron mobility. FTO glass was coated with ZnO thin films by RF-magnetron sputtering; each film was deposited under different $O_2$:Ar ratios and RF-gun power. The optical transmittance of the ZnO thin film depends on the thickness and morphology of ZnO. The conversion efficiency was measured with the maximum value of 5.22% at an Ar:$O_2$ ratio of 1:1 and RF-gun power of 80 W, due to effective prevention of the electron recombination into electrolytes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.12 no.1
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• pp.50-55
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• 1999

We have investigated the $LiMn_2O_4$system as an cathode material for lithium rechargeable batteries. $LiMn_2O_4$spinel oxides have been synthesized by a solid state methode. We varied sintering time at a fixed sintering temperature of 75$0^{\circ}C$. In order to investigate the electrochemical properties of prepared $LiMn_2O_4$we assembled three-electrode cells using the working electrode as active material and Li metal as the counter and reference electrodes. The electrolyte was 1 M LiPE$_{6}$-EC:DEC(1:1 by volume). The particle size of sample synthesized at 75$0^{\circ}C$ ranged about 60$\mu m$. The discharge capacity of a cell involving spinel $LiMn_2O_4$ increased with increasing sintering time.e.

• Proceedings of the Materials Research Society of Korea Conference
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• 2008.05a
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• pp.45.1-45.1
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• 2008

• Journal of Korean Society of Water and Wastewater
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• v.16 no.6
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• pp.663-669
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• 2002

Electro-flotation (EF) has shown advantages, such as a high removal efficiency and easy control of bubble generation, over dissolved air flotation. However, the fundamental characteristics of the process have not been investigated in detail. According to recent modeling results from trajectory analysis, the size of the bubble is one of the most important factors that affect the efficiency of collision between bubble and particle. In this paper, the size characteristics of bubbles generated from EF under various conditions are measured using a new method for bubble size measurement, the Particle Counter Method (PCM). The size of the generated bubbles was found to be constant with respect to applied voltage but to vary with the electrode materials. These results and their implications are discussed.