• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• v.4 no.3
• /
• pp.185-193
• /
• 2000

A water treatment agent with antimicrobial activity(Ag-Os) was created by exchanging silver ion($Ag^{+}$) on calcined oyster shell powder. The desorption of the exchanged silver ion was negligible, thereby indicating a stable antimicrobial water treatment agent. The sterilization effect of Ag-Os on underwater microorganisms was then investigated. An MIC (Minimum Inhibitory Concentration) test result indicated that Ag-Os had an excellent sterilization effect on G-germs, such as Escherichia coli and Pseudomonas aeruginosa. Most germs were annihilated with an Ag-Os concentration of 200 ppm and contact time of 60 minutes. The sterilization effect was mainly dependent on the contact time. The zeta potential of the Ag-Os powder adsorbed on sand was measured relative to the concentration of exchanged silver ion. As the concentration of the exchanged silver ion increased, the surface charge density of the anions on the surface of the Ag-Os powder adsorbed on sand also increased. Accordingly, this result indicated that a higher silver ion than ion exchange capacity was present on the particle surface due to adsorption. Consequently, this increased concentration of exchanged silver ion would appear to significantly enhance the sterilization power.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1995.05a
• /
• pp.73-76
• /
• 1995

In this study, the slab waveguide was fabricated using potassium-nitride(KNO$_3$) or silver-nitride (AgNO$_3$) molten sources by ion-exchange process. The effective refractive indices of waveguide were measured by Prism-Coupling method. and The characteristics of waveguide(mode dispersion, effective diffusion depth. surface refractive index, diffusion coefficient, and refractive index profile etc,) were investigated by WKB method, In the case of potassium ion-exchange, the computer calculation showed that the refractive index profile of waveguide followed Gaussian function, the surface refractive index increased with ion-exchange time and the effective diffusion depth increased a little as ion-exchange time increased, while the surface refractive index of silver ion-exchanged waveguide decreased with ion-exchange time because of the ion depletion on the surface of waveguide, and the effective diffusion depth seriously with ion-exchange tim. Double ion-exchanged waveguide was fabricated by performing silver ion-exchange after potassium ion-exchange. Double ion-exchanged waveguide had a tight mode binding force since the surface refractive index was larger than single step ion-exchanged waveguide.

• Textile Coloration and Finishing
• /
• v.33 no.1
• /
• pp.24-30
• /
• 2021

In this study, PET containing 3% silver ion-exchange zeolite was mixed with cotton in a ratio of 6:4 to prepare a spun yarn to evaluate the tensile strength, absorption speed, absorption rate, antibacterial property, and the efficiency of deodorization. As a result, the following conclusions were obtained. First, it can be confirmed that silver ion exchange zeolite is evenly distributed inside and on the surface of the antimicrobial PET-SF through SEM. It was found that the tensile strength between the CVC sample mixed with silver ion zeolite PET and cotton and the normal cotton 100% sample was slightly lower in the CVC sample. Although the absorption speed and water absorption rate were measured to find out the moisture characteristics, it was confirmed that there was no significant difference. The contact angle was slightly larger in the antimicrobial CVC sample, but the time it took for the moisture to completely penetrate into the knit fabric was 0.85 seconds. In addition, it was found that out of the total mixing ratio, 40% of antibacterial PET was spun with regular cotton to produce yarn, which had an excellent bacteria reduction rate of 99.9% and a deodorization efficiency of 85%.

• Resources Recycling
• /
• v.17 no.5
• /
• pp.60-65
• /
• 2008

A study on the removal of silver(Ag) in copper electrolyte was carried out to produce high purity copper by using various method such as ion exchange resin, activated carbon adsorption, copper cementation with powder and wire, CuS precipitation. Parameters, such as reaction time, reaction temperature, addition amount etc. were investigated to determine the effective condition of silver removal. CuS precipitation and ion exchange using Lewatit TP214 was found to be effective. Especially, silver content in copper electrolyte was reduced from 10 ppm to less than 0.1 ppm by ion exchange with Lewatit TP214.

• Electrical & Electronic Materials
• /
• v.9 no.3
• /
• pp.284-290
• /
• 1996

The electrical properties of bulk galsses in the system Na$_{2}$O-CaO-Al$_{2}$O$_{3}$-B$_{2}$O$_{3}$-SiO$_{2}$ containing 20 to 30mol% sodium which have been subjected to a sodium .tautm. silver ion exchange reaction for 24, 36 and 48 hrs. were analysed by impedance spectroscopy method. Ion exchanged glasses exhibit activation energy values lower than those of the untreated ones. The electrical conductivity increase with sodium content and ion exchanging time. In this experiment the electrical conductivity exhibits a manximum value of 1.78*10$^{-4}$ S/cm at 200.deg. C which contains 30mol% sodium and subjects ion exchange reaction for 48hrs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1994.05a
• /
• pp.130-132
• /
• 1994

We fabricated Ag ion exchange glass waveguide. Generally, ion-exchange glass waveguide. are suitable for passive integrated optical components such as directional and star couplers. Its advantages include low loss, ease of fabrication, and low material cost. So, we faricated Ag ion-exchange glass waveguides in AgNO$_3$ melt solution from 2 mole %. And we used Sodalime glass as a substrate in the fabrication process. As the results, we observed multivalent ion-exchange in a typical sodalime glass. Diffusion coefficient and depth are predicted by actual experimental data of Stewart. The exchange rate in silver-ion-exchanged waveguides are compared to the exchange time of waveguide fabrication.

• Bulletin of the Korean Chemical Society
• /
• v.27 no.11
• /
• pp.1832-1838
• /
• 2006

The present paper is focused on sorption concentration of silver (I) on some complex-forming ion exchangers in the initial thiocyanate form and subsequent determination of Ag(I) in the phase of anion exchanger AN-25 by diffuse reflectance spectroscopy. The sorption and kinetic characteristics of the sorbents were investigated. The apparent stability constants of thiocyanate silver complexes in the ion exchanger phase were calculated. The sorption-spectroscopic method is proposed for Ag(I) determination in aqueous solutions. The calibration curve is linear in the concentration range of 10-200 mg/L (sample volume is 10.0 mL) and the detection limit is 2 $\mu$g/mL. The presence of $Na^+,\;K^+,\;Mg^{2+}$ (macrocomponents) as well as of Ni (II), Co (II), Cu (II) do not hinder the determination of silver (I).

• Electrical & Electronic Materials
• /
• v.8 no.3
• /
• pp.332-339
• /
• 1995

In this paper, it was investigated the guided field intensity distribution of the channel in the silver & potassium ion-exchange glass-waveguide. The guided field intensity distribution analysis of ion-exchange glass-waveguide was based on the combination of the WKB dispersion relationship method with a Gaussian distribution function of refractive index profile and the Field Shadow method to the modeling of the channel waveguide. As the results of the channel waveguide modeling, it was represented 2-dimensional and 3-dimensional field distribution of ion-exchange glass waveguide.

• Journal of Environmental Science International
• /
• v.13 no.1
• /
• pp.89-97
• /
• 2004

An author has been known that A-type zeolite supported with silver ions has excellent antibacterial activity. However, it is no research of concern in the antibacterial activity of eluted silver ions. This study tested the elution of silver ions from A-type zeolite silver ions in deionized distilled water and NaNO$_3$ aqueous solution. In NaNO$_3$ aqueous solution of 74mM to 588mM, it was found that the concentration of silver ions and electric conductivity increased with the increasing concentration of sodium ions, and equilibrated at 15 min, and the ion exchange equilibrium coefficient, k, is 1.3${\times}$10$\^$-3/. However, deionized distilled water is not equilibrated to pass 6 months. A-type zeolite sodium ions showed no antibacterial activity. It was found that antibacterial activity was exhibited even at the concentration of 10 nM of eluted silver ions, and E-coli died with the incorporation of 2.43${\times}$10$\^$8/ Ag ion/cell. antibacterial activity of A-type zeolite silver ions were mainly attributed to hydroxyl radical.

• Journal of the Korean Ceramic Society
• /
• v.27 no.1
• /
• pp.67-73
• /
• 1990

The behavior of optical properties of ion exchanged glasses was investigated inthis study. The used glasses were soda-lime-silica glasses that were produced by float process. The coloring effect by Ag colloids is measrued by spectral transmittance, color coordinates, dominant wavelength and excitation purity resulting from silver ions exchange of glasses immersed into the mixed molten salt with AgNO3. Ion exchange coloring of glasses made it possible to obtain glasses with a range from yellow to brown, and transmittance was decreased with increasing the amount of Ag colloids which reduced from Ag+ions. Also, obtain from yellow to reddish brown with increasing purity by reheating treatment in air for ion exchanged glasses. The size of Ag colloids are 0.02~0.1${\mu}{\textrm}{m}$ with ion exchange conditions.