• Journal of Sensor Science and Technology
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• v.6 no.4
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• pp.307-315
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• 1997

In this paper, a sample chamber which provide easy replacement of ISFET sensor and consume only small sample volume for electrolyte analysis is designed and a 4-channel electrolyte analyzer employing 2-point calibration method is implemented. In addition, we proposed sample loading detection circuit for minimizing sample and calibration solutions and implemented it. Developed electrolyte analyzer consists of control system part and flow system part. For the effective control of the developed hardware, system software is developed as three individual routines ; measuring routine, calibration routine and washing routine.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.183-187
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• 2006

The choice of solvents for electrolytes solutions is very important to improve the characteristics of charge/discharge in the Li-ion battery system. Such solvent systems have been widely investigated as electrolytes for Li-ion batteries. In this paper, the electrochemical properties of the solid electrolyte interphase film formed on carbon anode surface and the solvent decomposition voltage in 1 M LiPF6/EC:MA(x:y) electrolyte solutions prepared from the various mixing volume ratios are investigated by chronopotentiometry, cyclic voltammetry, and impedance spectroscopy. As a result, the solvent decomposition voltages are varied with the ionic conductivity of the electrolyte. Electrochemical properties of the passivation film were different, which are dependent on the mixture ratio of the solvents. Therefore, the most appropriate mixing ratio of EC and MA as a solvent in 1 M $LiPF_6/(EC+MA)$ system for Li-ion battery is approximately 1:3 (EC:MA, volume ratio).

• Clinical and Experimental Reproductive Medicine
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• v.18 no.1
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• pp.35-40
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• 1991

To find out the suitable method for blastomeres fusion of mouse 2-cell embryo using electric stimuli, these studies were carried out with various voltages (1.0 KV, 1.2 KV, 1.5 KV, 1.7 KV and 2.0KV), pulse duration times($50{\mu}\;sec$, $75/{\mu}\;sec$, $100{\mu}\;sec$) and different fusion solutions. In addition, the fused embryos were cultured for 72-80hr to observe their subsequent development. These results were summarized as follows: 1. The proportion of the fused embryos were 50.8%(34/67), 60.7%(34/56), 70.6%(48/68), 66.7% (48/72) and 85.3% (58/68) after stimuli of 1.0KV, 1.2KV, 1.5KV, 1.7KV and 2.0KV for $100{\mu}\;sec$ with 2 times, and the electric stimulation at 2.0KV(85.3%) was the most effective voltage on the blastomere fusion. 2. For in vitro development, blastocysts of the fused embryos were cultured for 72-80hrs in $M_{16}$ medium. The group(52.1%) treated with 1.5KV for $100{\mu}\;sec$ with 2 times showd higher development rates than those any other group. However, these results were not corresponded to those of the rates of blastomere fusion. 3. There were no significant differences among the rates of blastomeres fusion to 50(70.6%), 75(71.9%), and 100(78.0%) ${\mu}sec$ stimulation at 1.5KV with two times. However, the development rates of the fused embryo in vitro were 52.1%(25/48), 28.3%(13/46) and 9.4%(3/32) at the above conditions, and the development rates of fused embryo increased as the pulse duration times increased. 4. The rates of the blastomeres fusion were 38.9% (28/72) or 70.6% (48/68) in electrolyte (PBS) or non-electrolyte(0.3M mannitol) solution. The development rates of the fused embryo were 32.1% (9/28) or 52.1%(25/48) in the above fusion solutions, and non-electrolyte-treated group showed higher development rates of embryo than that of electrolyte-treated group.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.2
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• pp.51-55
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• 2003

The interrelation into nucleation and thermodynamic parameters of solutions has been established by plotting of various dependencies: the enthalpy of dissolution, solubility product and super-solubility on ionic salt radii and also the extent of deviation from an ideal Debye -Huckel model of electrolyte solution on solubility product. The possible methods of perfect crystal growth from aqueous solution have been found a priori by separating of known set of pair values of solubility and super-solubility into no less than six-nine characteristic and distinctive sub-sets.

• Journal of the Korean institute of surface engineering
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• v.19 no.2
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• pp.44-50
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• 1986

Effects of cathodic overvoltages on the electrodeposition of lead from electrolyte containing lead chloride, ammonium acetate and sodium succinate was investigated at 20$^{\circ}C$. The use of organic additives, phenol and gelatin was found effective to inhibit the growth of dendritic crystals. At the carthodic overvoltages higher than 0.2V, the lead deposit becames less compact even in the presence of organic additives. The applications of agitation and pulse current promoted compact and shiny deposits.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.160-160
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• 2013

Dye-sensitized solar cells (DSSCs) have attracted much attention because of their moderate light-to-electricity conversion efficiency, easy fabrication, and low cost. At present, platinum (Pt) is used as a counter electrode in DSSCs. However, it is found that Pt dissolves in iodide electrolyte solutions and creates chemical compound such as PtI4 and H2PtI6. Carbon based materials are one of candidates for a counter electrode of DSSCs. We prepare two types of graphite oxides by different chemical treatments; original graphite oxide, hydrazine treated graphite oxide. Each graphite oxide and magnesium nitrate dispersed in deionized water are prepared as solutions for electrophoretic deposition (EPD). Each graphite oxide electrode is deposited on fluorine-doped tin oxide (FTO) substrate by EPD method. Structural and electrochemical properties of each electrode are investigated by field-emission scanning electron microscopy and electrochemical impedance spectroscopy, respectively.

• Journal of the Korean institute of surface engineering
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• v.21 no.4
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• pp.160-167
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• 1988

Electrochemical behaviors od chromium electrodeposition from 0.05M chromium (III) sulface complexes in aqueous solutions using sodium formate-glycine mixtures as a complexing agent were studied. In the cathodic current-potential cures, it is found that the intial limiting current of Cr(III) is proportional to square root of scan rate and activiation energy from Arrhenius plot is s obtained 3.05Kcal/mol. From this results, the reaction is considered, Cr3++e longrightarrow Cr2+, which is controlled diffusion of Cr (III). It is also found that the chromium is deposited when the potential reaches to hydrogen evolution potential. Effects of NaSCN as a catalyser in the electrolyte were investigated NCS- anion seems to react strongly by specific absorption at the inner HelmholtZ layer, so that, it is considered to suppress the electrodeposition reaction reaction for chromjum, and also it is considered multipe-bridge such as Cr(III)-NCS---M(M;cathode).

• Journal of the Korean institute of surface engineering
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• v.15 no.4
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• pp.192-207
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• 1982

A study has been made of the interaction parameters of Zn other elements in dilute solutesd solution of molten cadmium alloys over the temperature range of 450 to 570$^{\circ}C$. The experi-mental measurementss were made in a touch instant cell using a fusedd Licl-KCl electrolyte. The activity of zinc in binary and ternary solutions sexhibiteds a strong positive deviation from Raoult's law. The addition of silver, indium or lead increased the activity of zinc whereas addition of copper, bismuth or tin decreased the zinc activity slightly. The results for all the metallic solutions showed a linear dependence of reciprocal of ab-solute temperature over the experimental range. The interaction parameters obtained are as follows.

• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.183-195
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• 2014

In order to study the mineralogical characteristics of a cathodic deposition-metallic powder, electrowinning experiments were carrier out on different electrolytic solutions at varying electric distances and electric currents. Under the same experimental conditions, Cu recovery was obtained much more effectively using a sodium chloride electrolyte than with a sulfuric acid electrolyte. In XRD analysis, copper ($Cu^0$), chalcanthite and cuprite were identified in the sulfuric acid electrolyte, while copper, nantokite and chalcanthite were observed in the sodium chloride electrolyte. In the sodium chloride electrolyte solution, increasing the electric distance and the electric current increased the Cu recovery rate, anode weight and anodic corrosion. The results of XRD analysis with non-pulverized cathodic deposition-metallic powder showed the average copper crystallite size was increased by increasing the electric current and decreasing the electric distance. It is suggested that the mass transfer was controlled with diffusion on the boundary between the electrode and the electrolytic solution due to the formation of dendrite copper.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.15-27
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• 1990

Effects of oral administration of electrolyte solutions were studied in experimentally dehydrated adult sheep. By the latin square method five ruminal fistulated sheep were examined and dehydrated by deprivation of feed and water for 72 hours. Tap water, physiological saline, 0.45% NaCl+120 mM/L glucose and 0.9% NaCl+1% propylene glycol solution were orally administrated after dehydration, respectively. Rehydration effect and modification of the rumen function were compared. 1. After 72 hours of deprivation of feed and water, sheep were hypertonic dehydrated and blood acid-base parameters were not significantly changed. And there was marked increase in ruminal pH and decrease in ruminal total volatile fatty acid(VFA) concentration. 2. After the fluids administration the changes in blood acid-base parameters were not significant in all groups. 3. Although glucose fermentation in the rumen was observed, 0.45% NaCl+120 mM/L glucose was more effective in rehydration than physiological saline and tap water. But it was difficult to know the rehydration effect of 0.9% NaCl+1% propylene glycol solution exactly because of excessive increase in plasma osmolality. 4. After refeeding, total concentration and proportions of ruminal volatile fatty acid(VFA) were not significantly different among groups and recovered to normal concentration but not in proportions after 2 days in all groups. 5. In vitro cultured ruminal protozoa were susceptible to the decrease of the pH and osmolality.