• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.2
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• pp.188-197
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• 2016

Objectives: The purpose of this study was to evaluate the ozone exposure levels and the variations in ozone concentration in a semiconductor fabrication facility and office in relation to the ozone concentration in the outdoor air. Methods: This study was performed in an office, semiconductor fabrication facility(such as etching, diffusion, diffusion plenum), and outdoors from June to August, 2015. Measurements were taken six times at the same places using an active sampler(pumped) and real-time equipment. Ozone monitoring by the active sampler method and analysis were carried out by OSHA Method ID-214. Real-time measurement was carried out by ozone measuring equipment using a non-dispersive ultraviolet absorption method. Results: Ozone concentrations in the semiconductor fabrication facility and office were 0.7~7.1 ppb in area samples and 0.72~4.07 ppb in real-time measurement, which were 0.88~8.88% of the occupational exposure limit. The concentration of ozone generated by a laser printer in the office was less than 2 ppb. There was not a significant difference between ozone concentrations before and after using the laser printer. The indoor/outdoor concentration ratio(I/O ratio) in the semiconductor fabrication facility and office was 0.05 and 0.06, respectively. Conclusions: All the samples contained ozone levels lower than the occupational exposure limit and it was confirmed that the concentration of outdoor ozone had no significant effect on indoor ozone concentration.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1837-1839
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• 2003

Recently deep interests have been paid on the effective generation of ozone, which has been widely used for water treatment, deoderization, color removal and chemical processing of exhausted smoke. The silent discharge reaction has been proposed as the most effective in the many ozone generation methods by electric discharge, because silent discharge excel others in the condition of high ozone generation yield and low power consumption. In this paper, ozone water generated system measure with silent discharge characteristics and pulsed power supply.

• Particle and aerosol research
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• v.18 no.1
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• pp.1-8
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• 2022

Since 2019, the corona virus has been continuously affect human life. In particular, in the indoor space where people live, infection by airborne transmission of viruses is a problem. Among them, the spread in the subway, which is the main mode of transport for humans, can be serious. To solve this problem, our research team developed an ionic wind collector to collect and remove corona virus using an ionic wind collector and ozone. In order to apply the ionic wind collector to the subway, it must operate in two modes. Because large amounts of ozone are harmful to the human body. There is a mode that collects bio-aerosol from the air using ionic wind and a mode that inactivates viruses floating in the air by generating a large amount of ozone. As the applied voltage increased, the cleaning ability of the ionic wind collector increased, and the farther the distance between the discharge electrode and the ground plate, the higher the cleaning ability even at low current. In addition, clean air delivery rate (CADR) of an ionic wind collector was up to 5.5 m³/min. As a result of measuring the amount of ozone generated, it was confirmed that 50 ppb to 250 ppb was generated, and it was confirmed that ozone generation was controllable in the ionic wind dust collector.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.5
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• pp.460-466
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• 2001

The oxidizing power of ozone is the greatest of all commercially available oxidizers and thus ozone is taking the place of chlorine for water treatment. For energy-effective treatment of water, ozone should be generated in high concentration. A silent glow discharge ozonizer is high effective in industrial aspect and thus is the most widely used. We found that the key parameters associated with the ozone generation rate are the driving voltage of the discharger, the discharge rate and the temperature of the ozone generation tube. For an easy control of these parameters, we build a monitoring system with graphical user interface. This system is based on Windows-98 PC, programmed with C++ and LabView.

• The Journal of Natural Sciences
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• v.10 no.1
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• pp.93-102
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• 1998

In order to study on the bleaching efficiency of flex fabrics, ozone which has been produced by an ozone generator, has been contacted with flex fabrics in water at various conditions. The equipments used for the ozone reatment of flex fabrics were the ozone generator and a liquor/ozone contactor. For the study of the bleaching efficiency on flex fabrics, the Hunter's whiteness, tensile strength, microscopic properties of the ozone treated flex fabrics were measured. The concentration of generated ozone was increased, as the voltage increase, flow ratio decrease and oxygen amount increase. The bleaching efficiency of ozone treated fabrics was increased with increasing the net concentration of ozone. The whiteness ozone of treated fabrics was found to be best when treated temperature was $0-15^{\circ}C$ and treated time was 20 min. The tensile strength of treated fabrics decreased as the treating time increased, and as the temperature raised.

• Journal of Environmental Science International
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• v.32 no.3
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• pp.197-204
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• 2023

This study aims to inactivate Artemia sp. (Zooplankton) in ballast water through the dielectric barrier discharge (DBD) plasma process. The DBD plasma process has the advantage of enabling direct electric discharge in water and utilizing chemically active species generated by the plasma reaction. The experimental conditions for plasma reaction are as follows; high voltage of 9-22 kV, plasma reaction time of 15-600 s, and air flow rate of 0.5-5.5 L/min. The results showed that the optimal experimental conditions for Artemia sp inactivation were 16 kV, 60 s, 2.5 L/min, respectively. The concentrations of total residual oxidants and ozone generated by plasma reaction increased with an increase of in voltage and reaction time, and the concentration of generated air did not increase above a certain amount.

• Textile Coloration and Finishing
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• v.7 no.1
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• pp.32-42
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• 1995

In order to reduce the amount of waste water generated from textile dyeing process and processing water, cotton fabric was bleached with ozone in ozone/water contact system, and dyed. The results obtained from the measurement of whiteness, reflectance, tensile strength, color difference, and K/S value of treated samples were as follow : 1) In ozone bleaching, factors affect whiteness most are treatment time and ozone dosage. As treatment time is lengthened, whiteness increases. Futhermore, bleaching effect is high in acidic treatment, but low in alkaline treatment. 2) As bleaching goes on, maximum absorption wave length shifts to shoter wavelengths. 3) As treatment time is lengthened or pH of treatment is low, tensile strenth of treated fabric decrease. 4) In all cases, color difference of dyed cotton fabrics in above 2% o.w.f. dyestuff concentration don't go beyond 1∼2 AN unit, compared with standard.

• Journal of the Korean Electrochemical Society
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• v.11 no.3
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• pp.135-140
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• 2008

An electrochemical generation of ozonized water was investigated by using ${\beta}-PbO_2$ as an anode and tap water as an anolyte. According to the potentiometric ozone detection which utilizes potential differences arisen from a chemical reaction of ozone and iodide, increasing tendency of ozone concentration on electrolysis time could be observed to show the maximum value of 8 ppm at an electrolysis time of 10 min. Ozone could be generated promptly even at an electrolysis time of 10 sec., suggesting great advantages of this electrochemical process in terms of simplicity and readiness that might be applied directly to practical uses including medical and/ or food industries. Influences of electrolysis on the properties and surface conditions of a $PbO_2$ electrode were also discussed from the results of cyclic voltammetry, scanning electron microscope, and X-ray diffractometer.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.9
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• pp.80-85
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• 2011

In this paper, complex discharge type ozonizer with a screw type electrode has been designed and manufactured for environmental improvement using low power and high efficency ozoniazer. The complex discharge type ozonizer is equipped with three electrodes{central electrode(CE), internal electrode(IE) and external electrode(EE)}. Ozone of the complex discharge type ozonizer is generated by superposition of silent discharge and surface discharge in discharge space as a screw type CE and IE are respectively applied to AC high voltage of inverse-polarity has $180[^{\circ}]$ phase difference, EE is common electrode. In this time, when oxygen has been used as supplied gas, the maximum values of ozone concentration, ozone generation and ozone yield were obtained as 8,334[ppm], 3,249[mg/h] and 65.3[g/kwh].

• Elastomers and Composites
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• v.53 no.3
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• pp.168-174
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• 2018

Natural rubber (NR) and bromo-isobutylene-isoprene rubber (BIIR) were compounded with other formulation chemicals through polymer blending via a mechanical mixing method. After rubber vulcanization by hot-press compression molding, the cure characteristics, mechanical properties, and ozone resistance of the NR/BIIR blends were measured. As the BIIR content increased, the maximum torque of the blends decreased, while the optimum cure time and scorch time tended to increase. Furthermore, the hardness of the blends increased with increasing BIIR content, reaching the maximum value at 75 wt% BIIR, and decreased with a further increase in the BIIR loading. The tensile strength and elongation at break decreased with an increase in the BIIR content, reaching the minimum value at 75 wt% BIIR, and increased with a further increase in the BIIR content. In the ozone resistance test, cracks were not generated when the BIIR content was more than 75 wt%.