• Composites Research
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• v.18 no.1
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• pp.23-29
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• 2005

In this work, the effect of ozone treatment of montmorillonite (MMT) on the surface characteristics of montmorillonite and the thermal stability of MMT/polypropylene (PP) nanocomposites was investigated. The surface properties of MMT were determined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). Also, the thermal stability of nanocomposites was investigated in thermogravimetric analysis (TGA). As a result, it was found that the silicate interlayers of the organically modified MMT (D-MMT) were increased by about 11${\AA}$, as compared with the MMT. Also, FT-IR showed that a new peaks at $2800\~2900\;cm^{-1}$ appeared due to the $CH_2$ mode in the D-MMT The ozone treatment of the MMT led to an increase of SiO or $SiO_2$ groups on MMT surfaces, resulting in increasing the oxygen-containing functional groups on MMT. The ozonized MMT had higher thermal stability than that of untreated nanocomposites. This was due to the improvement of interfacial bonding strengths, resulting from the acid-base interfacial interactions between PP and MMT.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.2122-2126
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• 2008

With the degradation of water quality and, at the same time increased water usage, the sources of high quality, for examples, river/stream, municipal reservoir, wells, artisan and surface water, are diminishing. Therefore, the importance of water quality has been emphasized over the years through publications and various literature sources. Even though considerable research has resulted in significant strides for providing interpretive information and mitigation strategies for improvement of waters, the quality of which is still questionable. This study aims to propose a completely independent self-contained system for purifying waters, solar-powered ozone generator. It is a semi-permanent and cost effective environmental solution. Functions of ozone treatment are: 1) to maintain oxidative flexibility, 2) remove harmful chemicals, wastes, and other substances, and 3) prevent epizootic microbial outbreaks. Recent advances in technology have allowed the development of the practical, self-contained and independent solar powered device. Solar electrical producing panels that charge batteries are the key to using these systems anywhere electrical power is not available. This paper invites the readers to examine the problem and consider the viable, proven solution the solar powered ozone purifying system. This paper also introduces basic concept and background of solar powered ozone generators and examine its feasibility for improving water quality in rivers and streams.

• Journal of Industrial Technology
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• v.39 no.1
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• pp.1-5
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• 2019

In this study, we examined the effect of NO addition on the ozone-induced soot oxidation activity of $LaMnO_3$ perovskite catalysts. The addition of 10~20% NO ($NO_2$) with respect to the concentration of ozone effectively enhanced the rate of ozone-induced soot oxidation rate over $LaMnO_3$. However, the excessive addition of NO ($NO_2$) was detrimental to ozone-induced soot oxidation activity. It is supposed nitrogen oxides would adsorb on the catalyst and then react with carbon-oxygen species developed on soot surface, but an excessive addition of nitrogen oxide would inhibit the formation of carbon-oxygen species, which is a key intermediate in the reaction, and consequently suppress the oxidation rate of soot.

• Elastomers and Composites
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• v.40 no.3
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• pp.188-195
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• 2005

Chemical and physical changes and the contents of functional groups in the carbon black surface after the ozone treatment was investigated using elemental analysis, pH, tint strength, DBP, $N_2SA$, IA, and acid-base reaction. As the treatment time was increased, surface structure, particle size and surface area of carbon black did not change, while surface oxygen contents increased, and pH decreased and then saturated after $1{\sim}2$ hour. The contents of carboxylic, lactone, hydroxyl, and carbonyl groups were analyzed with four bases such as $NaHCO_3,\;Na_2CO_3,\;NaOH$, and $NaOC_2H_5$. Before oxidation, the carbonyl group was dominantly present on the surface, but by increasing the treatment time, the contents of the carboxylic and carbonyl groups increased to a saturated level after $1{\sim}2$ hour. Before and after the oxidation, the lactone and hydroxyl groups were nearly absent. These results showed that the reaction mechanism of carbon black and ozone is similar to that of ethylene and ozone. Weight of oxidized carbon black was increased after treating AIBN, while free radical was slightly decreased by ESR analysis. When carbon black was treated with organic compounds containing mercapto- groups, the results of ESR showed that free radical peak intensity was almost diminished compared to original carbon black.

• Applied Chemistry for Engineering
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• v.35 no.1
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• pp.23-28
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• 2024

Cesium is a potential toxic contaminant due to its high solubility, which allows it to easily penetrate the human body and potentially induce cancer or DNA mutations. In this study, oxygen functional groups were introduced on activated carbons (ACs) by ozone treatment to enhance the cesium adsorption capacity. As the ozone treatment time increased, the oxygen content on the ACs surface increased. Subsequently, the electrostatic interaction between ACs and cesium enhanced, resulting in higher cesium ion adsorption efficiency across all samples. In particular, the sample treated with ozone for 7 minutes at an internal ozone concentration of 50000 ppm had roughly 12% greater oxygen functional group content and the highest cesium removal effectiveness (97.6%). Meanwhile, samples treated for 5 minutes showed a 0.3% cesium removal rate difference compared to those treated for 7 minutes, which was caused by the surface chemical similarity of the two samples due to the reactive characteristics of ozone gas. However, the cesium adsorption performance of ozonated activated carbon seems to be mainly influenced by the amount of oxygen functional groups introduced to the surface, although the specific surface area and pore structure of the activated carbon are also important.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.11
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• pp.104-108
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• 2012

Flexible organic thin film solar cell device with Bulk Hetero-Junction (BHJ) structure was fabricated with blended conjugated polymer of PCDTBT : $PC_{71}BM$ as active layer. Surface of ITO anode for the organic solar cell device was treated with ozone. The organic solar cell device with bare ITO showed short circuit current density ($J_{sc}$) of $8.2mA/cm^2$, open-circuit voltage ($V_{oc}$) of 0.73V, fill factor (FF) of 0.36, and power conversion efficiency (PCE) of 2.16%, respectively. The organic solar cell device with ozone treated ITO anode revealed distinctively improved performance parameters:$J_{sc}$ of $9.8mA/cm^2$, $V_{oc}$ of 0.82V, FF of 0.43, PCE(${\eta}$) of 3.42%.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.39-47
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• 2013

This study demonstrates the oxidative degradation of pharmaceutical compounds during ozonation of surface waters in Ulsan. Diclofenac, carbamazepine, bezafibrate, and ibuprofen were selected as surrogate pharmaceutical compounds, and ozonation experiments were performed using raw waters collected from the Sayeon Dam and the Hoeya Dam in Ulsan. Diclofenac and carbamazepine which have high reactivity with molecular ozone showed higher removal efficiencies than bezafibrate and ibuprofen during ozonation. The addition of tert-butanol, a hydroxyl radical scavenger, increased the removal efficiencies of diclofenac and carbamazepine by increasing the ozone exposure. However, the oxidation of bezafibrate and ibuprofen was inhibited by the presence of tert-butanol due to the suppression of the exposure to hydroxyl radical. The elimination of the selected pharmaceuticals could be successfully predicted by the kinetic model base on the $R_{ct}$ concept. Depending on the experimental condition, $R_{ct}$ values were determined to be $(1.54{\sim}3.32){\times}10^{-7}$ and $(1.19{\sim}3.04){\times}10^{-7}$ for the Sayeon Dam and the Hoeya Dam waters, respectively. Relatively high $R_{ct}$ values indicate that the conversion of $O_3$ into $^{\cdot}OH$ is more pronounced for surface waters in Ulsan compared to other water sources.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.104-105
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• 2007

In this study, characteristics of silver ink-jet printing were investigated under various substrate treatments such as substrate heating, hydrophobic coating, and ultraviolet(UV)/ozone soaking. Fluorocarbon(FC) film was spin-coated on the polyimide (PI) film substrate to obtain a hydrophobic surface. Although hydrophobicity of the FC film could reduce the diameter of the printed droplets, the singlet images printed on the FC film surface showed irregularities in the pattern size and the position of the printed droplet along with droplet merging phenomenon. The proposed UV/ozone soaking of the FC film improved the uniformity of the pattern size and the droplet position after printing and substrate heating was very effective way in preventing droplet merging. By heating of the substrate after UV/ozone soaking of the coated FC film, silver conductive lines of 78-116 ${\mu}m$ line were successfully printed at low substrate temperatures of $40^{\circ}C$.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.157-162
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• 2013

A good level of biosecurity practice is important for efficient porcine reproductive and respiratory syndrome (PRRS) control. In the current study, disinfecting ability of ozone against PRRS virus (PRRSV) was evaluated in comparison with ultraviolet (UV) and an organic acid-based disinfectant to assess the possible use of ozone for disinfecting farm vehicles, equipments, and materials to reduce the risk of new virus introduction. For in vitro evaluation, the levels of infectious virus and viral RNA were determined on the swabs collected from the floor surface of each room treated with either ozone, UV or the disinfectant up to 30 min after contamination with 100 mL of VR2332 ($10^5\;TCID_{50}/mL$). For in vivo evaluation, 3, 4-week old, PRRS-free pigs were housed into those rooms right after the last swab collection. Then the pigs in each room were injected intramuscularly with the corresponding swab samples collected at the last time point and pooled per each room. Although ozone, UV, and the disinfectant significantly reduced the levels of PRRSV RNA contamination, ozone was most effective in removing the viral RNA. In addition, the virus collected after at least 10 min exposure to ozone failed to replicate in pigs while the virus collected after treatment with UV and the disinfectant for 30 min still replicated in pigs. Based on the results, it was concluded that ozone is more effective in inactivating PRRSV as compared with UV and the organic acid-based disinfectant.

• Journal of IKEEE
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• v.23 no.2
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• pp.431-437
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• 2019

This work was carried out ozone generation and TCE decomposition characteristics using dielectric ball materials filled barrier discharge reactor and catalyst's reactor for ozone decomposition. Ozone concentration generated from $Al_2O_3$ or $TiO_2$ filled barrier discharge reactor was so high compared with non-filled discharge reactor. This reactor is good discharge structure for generating the high ozone concentration. In addition, TCE decomposition rate and COx conversion rate increased using $MnO_2$ filled discharge reactor, because ozone was decomposed at the same discharge space on the surface of $MnO_2$ catalysts. To identify the $MnO_2$ catalytic effects, TCE decomposition rate reached to 100[%] by the decomposition of ozone at $MnO_2$ catalyst's reactor by the arrangement of $Al_2O_3$ filled discharge reactor and $MnO_2$ catalyst reactor. Finally, $MnO_2$ catalyst is good materials for the decomposition of ozone and this process will be useful for decomposing VOCs such as TCE.