• 한국세라믹학회지
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• 제32권10호
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• pp.1093-1102
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• 1995

Water-soluble phosphate glasses containing Ag or Cu ion were prepared through melting process. Then the powdered glass samples were dissolved in D.I. water at room temperature with changing the dissolution time. In terms with the glass composition, dissolution characteristics, bactericidal effects and cytotoxicities were investigated. Dissolved amounts increased uniformly with dissolution time, and the dissolution rate was higher for ternary glass than for binary glass and with less metal oxide amount. And the dissolution rate of the glass with Ag ion was higher than that with Cu ion, and the bactericidal effect of the glass with Ag ion was also greater. Solution with more than 25 ppm of Ag was observed to have strong cytotoxicity to L929, and solutions of lower Ag concentration or with Cu seemed to have little cytotoxicity.

• Corrosion Science and Technology
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• 제4권2호
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• pp.45-50
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• 2005

A 3% NaCl solution of 1 $dm^3$ circulated with 1.5 $dm^3/min$ by a pump for 24 h in the presence of magnetic field. An iron plate immersed in a $100cm^3$ of test solution for 24 h. The rest potential and pH on surface fixed after 3 h. Containing 0~120 ppm of Fe(II) ion, the dissolution in the magnetically treated solution rose comparing with that in the non-magnetically treated solution. The dissolution amount reached to maximum at 50 ppm, then fixed in the non-magnetically treated solution. When Fe(II) ion existed in the magnetically treated solution, dissolution accelerated a little. In the non-magnetic treated solution containing 10~125 ppm of Fe(III) ion existed, the dissolution accelerated. The dissolution amounts reached to maximum at 50 ppm, then decreased from maximum value. In the magnetically treated solution, the dissolution amounts reached to minimum until 50 ppm, then increased from minimum value. The dissolution amounts affected larger with increasing of magnetic flux density. Fe(II), Fe(III) ions and magnetic treatment affected to formation of $Fe(OH)_2$ and/or $Fe_3O_4$ films. The magnetically treated effects memorized about one month.

• 한국세라믹학회지
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• 제34권1호
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• pp.13-22
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• 1997

은 이온과 구리 이온을 동시에 함유하는 살균용 인산염계 수용성 유리를 용융법으로 제조하였다. 분말상의 유리 시편을 상온의 증류수에 넣어 조성과 시간에 따른 용해 특성을, bulk상 시편에 대해서는 용해 전.후의 표면변화를 각각 관찰하였고, 살균 효과 및 세포독성을 평가하였다. 은 이온:구리 이온=1:1인 조성에서 최대 용해량을 나타내었으며 용해거동은 초기부터 total dissolution이 지배적이었다. 시간의 경과에 따라 용해는 진행이 되지만, 표면에 생성되는 새로운 층은 관찰되지 않았다. Pseudomonas sp, e. coli, staphylococcus aureus, 및 salmonella균에 대한 살균 효과는 용해량의 증가에 따라 증가하여 우수한 살균효과를 나타내었다. L929 세포에 대한 독성 실험 결과, 은 이온의 농도가 10ppm이상에서만 독성을 나타내었다.

• 전기화학회지
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• 제11권3호
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• pp.159-164
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• 2008

변전위법, 순환전압전류법, 대시간전류법 및 대시간전기량법을 이용하여 구리의 산화 용해반응에 미치는 $Cl^-$의 영향을 조사하였다. 아르곤 분위기의 NaCl 수용액에서 Cu의 산화 용해반응은 전반응식 $Cu+2Cl^{-}{\rightleftharpoons}{CuCl_2}^{-}+e^-$ 에 따라 일어나며, Cu 표면에 $Cl^-$가 흡착하는 과정에 잘 맞는 등온식은 Temkin 흡착등온식 임을 알 수 있었다.

• 한국세라믹학회지
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• 제37권5호
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• pp.511-515
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• 2000

The effect of Ba2+ ion dissolution with different pH and amount of PAA on microstructural changes of green and sintered bodies and its electrical properties was studied in aqueous nano-size BaTiO3 slurry system. The dissolution of Ba2+ was least at strong base, pH 10.8 and by addition of amount of 0.15 wt% PAA. The green body with the lowest of dissolution of Ba2+ at pH 10.8 and 0.15 wt% PAA had minimum values of average pore size, 40nm and shown high increase of sintered density. The compact sintered at 125$0^{\circ}C$ for 2 hr with highest Ba2+ dissolution had low density and dielectric constant due to abnormal grian growth. However, the sintered body with the lowest Ba2+ dissolution had high sintered density and then shown high dielectric constant.

• Nuclear Engineering and Technology
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• 제53권9호
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• pp.2918-2925
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• 2021

The efficiency of decontamination of model spent ion exchange resins, contaminated with magnetite and hematite, with mineral acid solutions, and using electro-decontamination, was evaluated. It has been shown that effective hematite dissolution occurs in concentrated mineral acid solutions. However, the use of direct current increases the decontamination efficiency of spent ion exchange resins contaminated with hematite. It is determined that with increasing voltage and acid concentration, the dissolution efficiency of hematite deposits increases and can exceed 99%. It has been shown that hematite dissolution is accompanied by secondary adsorption of radionuclides due to ion exchange, which can be removed with sodium nitrate solutions.

• Corrosion Science and Technology
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• 제5권2호
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• pp.39-44
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• 2006

The dissolution amount of Zn plate was $0.058mg/cm^2$ in the non-magnetically treated solution, and was $0.059mg/cm^2$ in the magnetically treated solution after 24 hours of immersion. The magnetic treatment had no effect to corrosion of Zn plate as pH on surface was not recognized the difference. The addition of Zn(II) ion in the solution was prepared to the effects of corrosion and dissolution of Fe. The regularity was not obtained the effect of the magnetic treatment on the dissolution of Fe plate.

• 한국세라믹학회지
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• 제22권1호
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• pp.35-39
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• 1985

Synthetic mica $NaMg_{2.5}(Si_4O_{10})F_2 (Na-TSM)$ was treated with HCl solution and H-type exchange resin to investigate the chemical stability and the ion exchange by measuring the dissolution of chemical components and the exchanged $H^+$ ion. The replacement of $Na^+$ ion occurred in contact with HCl solution and H-type ion exchange resin at the surface of Na-TSM particles reached $Na^+$ ions at maximum value of 70~80%. $Mg^{2+}$ ion of octahedral layer became to dissolve from the pH2 solution and th amount of it dissolved in-creased almost proportional to $H^+$ ion concentration from around 0.02N $H^+$ ion equilibrium concentration. The crystalline structure of Na-TSM was destructed by dissolution of Mg2+ ion in cncentrated hydrochloric acid solution and resulted silica gel precipitation.

• Corrosion Science and Technology
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• 제6권6호
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• pp.311-315
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• 2007

The anodic polarization behavior of equiatomic TiNi shape memory alloy with pure titanium as a reference material was investigated by means of open circuit potential measurement and potentiodynamic polarization technique. And the structure of passive films on TiNi intermetallic compounds was also conducted using AES and ESCA. While the dissolved Ni(II) ion did not affect the dissolution rate and passivation of TiNi alloy, the dissolved Ti(III) ion was oxidated to Ti(IV) ion on passivated TiNi surface at passivation potential. It has also been found that the Ti(IV) ion increases the steady state potential, and passivates TiNi alloy at a limited concentration of Ti(IV) ion. The analysis by AES showed that passive film of TiNi alloy was composed of titanium oxide and nickel oxide, and the content of titanium was three times higher than that of nickel in outer side of passive film. According to the ESCA analysis, the passive film was composed of $TiO_2$ and NiO. It seems reasonable to suppose that NiO could act as unstabilizer to the oxide film and could be dissolved preferentially. Therefore, nickel oxide contained in the passive film may promote the dissolution of the film, and it could be explained the reason of higher pitting susceptibility of TiNi alloy than pure Ti.

• 한국결정학회지
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• 제11권4호
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• pp.224-230
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• 2000

We have been investigated the flaking mechanism of the soda-line glass. The pH of aqueous solution approached to 10 and increased with reaction time by ion exchange reaction between Na/sup +/ ion of glass and H/sup +/ ion of aqueous solution under the conditions of below pH 9 of start solution. The relationship between the pH of solution and reaction time shows logarithm. Total dissolution reaction of glass components by OH/sup -/ ion in aqueous seems to be dominant after the pH solution reached to 10 and the dissolution rate linearly increased with reaction time. The above tow reactions are simultaneously occurred. The dissolved Ca/sup 2+/ ions are reprecipitated on the glass surface to Ca-compound. The flakes are formed by the separation of leached layer of glass due to the different thermal expansion coefficient.