• 제목/요약/키워드: Ozone $(O_3)$

검색결과 501건 처리시간 0.03초

Temperature Dependent Characteristics of a Combined Discharge Type Ozonizer (CDO)

  • Fayzur Rahman;B. J. Chun;Lee, K. S.;Lee, D. I.
    • KIEE International Transactions on Electrophysics and Applications
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    • 제3C권3호
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    • pp.106-112
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    • 2003
  • A combined discharge type ozonizer was designed and manufactured. The increase or decrease of temperature greatly influences the characteristics of ozone concentration ( $O_{3con}$), ozone generation ( $O_{3g}$) and ozone yield ( $O_{3Y}$) of a discharge type ozonizer. The characteristics of ozone concentration, ozone generation and ozone yield rate were investigated by varying the gas flow rate (Q), the discharge power ( $W_{d}$) and the temperature (T). At T=25[$^{\circ}C$] the values of $O_{3con}$ were found as 5632, 4200, 2500 and l800[ppm] at Q = 1, 2, 4 and 6[l/min] respectively. At the same temperature the corresponding values of $O_{3g}$ were found as 662, 988, 1176 and l270[mg/h] and those of $O_{3Y}$ were found as 67, 102, 119 and 135[g/kWh] respectively. When the temperature is decreased to -50[$^{\circ}C$], the values of $O_{3con}$ were found as 9000, 6700, 4000 and 2800[ppm] respectively at Q = 1, 2, 4 and 6[l/min]. At the same value of temperature the corresponding values of $O_{3g}$ were found as 1220, 1576, 1882 and 2050[mg/h] and those of $O_{3Y}$ were found as 120, 159, 188 and 202[g/kWh] respectively. Hence as the temperature was decreased from 25 to -50[$^{\circ}C$], the efficiencies of ozone generation were increased by 79, 55, 58 and 49[%] respectively at Q = 1, 2, 4 and 6[l/min].]. 6[l/min].].

오촌처리가 가축 음용수 수질에 미치는 영향 (Effect of Ozone Treatment on Livestock Drinking Water Quality)

  • 최희철;이덕수;강희설;최종윤;유용희;한정대;노환국;권두중;김형호
    • 한국축산시설환경학회지
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    • 제7권3호
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    • pp.191-195
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    • 2001
  • 양돈.양계농장에서 가축음용수 수질향상을 위하여 이용이 확대되고 있는 오존발생기의 이용효과를 구명하고자 가축음용수에 3종의 표준균주를 접종 후 $O_3$A, $O_3$, UVL 등 3종류의 오존발생기를 공시하여 처리하였으며 그 결과는 다음과 같다. 1.가축음용수 오존처리시 pH는 $O_3$A구 6.84에서 8.01로, $O_3$구 6.81에서 7.59로 증가 했으나 UVL, Control구는 변화가 없었다. 2. 용존산소량은 $O_3$A구 6.43ppm에서 8.43 ppm으로, $O_3$구 6.40ppm에서 8.40ppm 으로 증가 했으나 UVL, Control구는 변화가 없었다. 3. 산화환원전위차는 $O_3$A구는 처리전 168.7 mV에서 502.3mV로 증가하였으며 $O_3$구는 164.3mV에서 409.7mV로 급격히 증가하였으나 UVL구나 Control구는 완만찬 증가를 보였다. 4. 가축음용수에 E. coli 08:$H^-$, Salmonella typhimurium, Staphylococcus aureus를 접종 후 오존처리시 처리 30분 후 세균수는 급격하게 감소하였다.

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$In_2O_3$ 계 산화물 반도체형 후막 오존 가스센서의 제조 (Fabrication of $In_2O_3$-based oxide semiconductor thick film ozene gas sensor)

  • 이규정
    • 전자공학회논문지T
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    • 제36T권1호
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    • pp.19-24
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    • 1999
  • In\sub 2\O\sub 3\ 계 산화물 반도체형 후막센서의 ppb 범위의 오존에 대한 감지특성을 살펴보았다. In\sub 2\O\sub 감지막은 오존에 감도가 상당히 높았지만 안정된 신호를 얻을 수 없었다. In\sub 2\O\sub에 3wt.% 의 Fe\sub 2\O\sub 3\를 첨가한 경우에는, 순수한 In\sub 2\O\sub 와 비교할 때 응답 시간과 감도에 있어서 감지 특성의 향상이 관찰되었지만, 센서 신호가 시간에 따라 계속 증가되는 경향은 크게 개선되지 않았다. 그러나 In\sub 2\O\sub:Fe\sub 2\O\sub 3\ 혼합 분말의 열처리는 감도가 감소하기는 하였지만 센서의 오존 응답 및 회복 특성을 증진시켰다. 특히 1300℃ 정도의 고온에서 혼합 분말을 열처리 하여 제조한 감지막은 감도의 감소는 있었지만 550℃ 의 측정 온도에서 빠른 응답 및 회복 특성과 센서 신호가 최대값으로 빠르게 수렴함을 확인할 수 있었다. 또한 이들 센서는 오존에 대해 센서 신호의 선형적인 농도 의존성을 나타내었으며, 반복 실험을 행할 때 센서 신호의 재현성을 보여주었다. 따라서 본 연구에서 제조한 후 막 가스센서를 사용하여 ppb 범위의 오존 농도를 신뢰성있게 측정할 수 있음을 확인할 수 있었다.

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이산화망간 촉매와 오존을 이용한 NO의 촉매 산화 특성 (Catalytic Oxidation of NO on MnO2 in the Presence of Ozone)

  • 진성민;정종수;이재헌;정주영
    • 한국환경과학회지
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    • 제18권4호
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    • pp.445-450
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    • 2009
  • In this study, the fundamental experiments were performed for catalytic oxidation of NO (50 ppm) on $MnO_2$ in the presence of ozone. The experiments were carried out at various catalytic temperatures ($30-120^{\circ}C$) and ozone concentrations (50-150 ppm) to investigate the behavior of NO oxidation. The honeycomb type $MnO_2$ catalyst was rectangular with a cell density of 300 cells per square inch. Due to $O_3$ injection, NO reacted with $O_3$ to form $NO_2$, which was adsorbed at the $MnO_2$ surface. The excessive ozone was decomposed to $O^*$ onto the $MnO_2$ catalyst bed, and then that $O^*$ was reacted with $NO_2$ to form $NO_3^-$. It was found that the optimal $O_3$/NO ratio for catalytic oxidation of NO on $MnO_2$ was 2.0, and the NO removal efficiency on $MnO_2$ was 83% at $30^{\circ}C$. As a result, NO was converted mainly to $NO_3^-$.

Comparing the Passivation Quality of Ozone and H2O Oxidant of Atomic Layer Deposited Al2O3 by Post-annealing in N2 and Forming Gas Ambients for Passivated Emitter and Rear Cell (PERC)

  • Cho, Young Joon;Chang, Hyo Sik
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.462-462
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    • 2014
  • The effect of rear passivation for passivated emitter and rear cell (PERC) using ozone and H2O oxidant of atomic layer deposited (ALD) Al2O3 was studied by post-annealing in N2 and forming gas ambients. Rear surface of PERC solar cell was passivated by Al2O3 grown by ALD with ozone and H2O oxidant. Al2O3 grown by ALD with ozone oxidant has been known to have many advantages, such as lower interface defects, low leakage current density. Its passivation quality is better than Al2O3 with H2O. Al2O3 layer with 10 nm and 20 nm thickness was grown at $150^{\circ}C$ with ozone oxidant and at $250^{\circ}C$ with H2O oxidant. And then each samples were post-annealled at $450^{\circ}C$ in N2 ambients and at $850^{\circ}C$ in forming gas ambients. The passivation quality was investigated by measuring the minority carrier lifetime respectively. We examined atomic layer deposited Al2O3 such as growth rate, film density, thickness, negative fixed charge density at AlOx/Si interface, and reflectance. The influences of process temperature and heat treatment were investigated using Sinton (WCT-120) by Quasi-Steady State Photoconductance (QSSPC) mode. Ozone-based ALD Al2O3 film shows the best carrier lifetime at lower deposition temperature than H2O-based ALD.

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Determination of Hydroperoxyl/superoxide Anion Radical (HO2·/O2·-) Concentration in the Decomposition of Ozone Using a Kinetic Method

  • Kwon, Bum-Gun;Lee, Jai H.
    • Bulletin of the Korean Chemical Society
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    • 제27권11호
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    • pp.1785-1790
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    • 2006
  • A novel kinetic method for determination of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ in ozone decomposition in water is described. In this study, potential interferences of $O_3$ and the hydroxyl radicals, $^{\cdot}OH_{(O3)}$, are suppressed by $HSO_3{^-}/SO_3{^{2-}}$. $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ formed in ozone decomposition reduces $Fe^{3+}$-EDTA into $Fe^{2+}$-EDTA and subsequently the well-known Fenton-like (FL) reaction of $H_2O_2$ and $Fe^{2+}$-EDTA produces the hydroxyl radicals, $^{\cdot}OH_{(FL)}$. Benzoic acid (BA) scavenges $^{\cdot}OH_{(FL)}$ to produce OHBA, which are analyzed by fluorescence detection (${\lambda}_{ex}=320nm$ and ${\lambda}_{ex}=400nm$). The concentration of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ in ozone decomposition has been determined by the novel kinetic method using the experimentally determined half-life ($t_{1/2}$). The steady-state concentration of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ is proportional to the $O_3$ concentration at a given pH. However, the steady-state concentration of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ in ozone decomposition is inversely proportional to pH values. This pH dependence is due to significant loss of $O_2{^{{\cdot}-}}$ by $O_3$ at higher pH conditions. The steady-state concentrations of $HO_2{^{\cdot}}/O_2{^{{\cdot}-}}$ are in the range of $2.49({\pm}0.10){\times}10^{-9}M(pH=4.17){\sim}3.01({\pm}0.07){\times}10^{-10}M(pH=7.59)$ at $[O_3]_o=60{\mu}M$.

오존 감수성 및 저항성 고추 품종의 생리생태 변화 (The Ecophysiological Changes of Capsicum annuum on Ozone-Sensitive and Resistant Varieties Exposed to Short-Term Ozone Stress)

  • 윤성철
    • 한국환경농학회지
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    • 제23권3호
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    • pp.128-132
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    • 2004
  • 공시된 세 품종의 고추에 대한 단기간의 오존 처리로 잎에서 나타나는 전형적인 증상은 갈색의 괴사 반응이었으며, 괴사가 심했던 오존 감수성인 다보탑과 같은 농도에서 괴사가 전혀 없었던 부촌 품종을 오존 저항성 품종으로 판단되었다. 고추의 두 품종에서 오존 처리에 의해 광합성 및 기공 전도도 등의 생리생태적 저해가 뚜렷이 나타났다. 그러나 잎에서 가시피해의 정도와 생리생태적 저해 정도와의 상호 연관성으로 고추에서의 오존 저항성 기작을 설명하고자 하였으나 생리생태적 반응으로 잎에서 발생하는 오존 저항성의 기작을 설명할 수 없었다. 다만, 고추에서 오존 처리에 의한 광합성 감소는 뚜렷한 기공전도도 감소와 명반응에서 광합성 기구들의 손상에 기인한다고 여겨진다. 그러나, 암반응에서 생화학적 반응을 설명할 수 있는 A-Ci curve 상에서는 오존 처리에 따른 효과를 찾을 수 없었다.

$O_3$/high pH, $O_3/H_2O_2$$O_3/{HCO_3}^-$ 시스템에서의 부식산의 분해 반응 특성 (Degradation of Humic Acids by Ozone/high pH, Ozone/Hydrogen Peroxide and Ozone/Hydrogen Carbonate System)

  • 신현상;김계월;이동석
    • 분석과학
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    • 제13권5호
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    • pp.652-658
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    • 2000
  • 오존 분자와의 직접반응경로 및 OH라디칼을 통한 간접반응경로를 통한 부식산의 분해특성을 TOC, $UV_{254}$ 그리고 오존 소모량의 변화를 통해 살펴보았다. 부식산의 분해를 위한 반응시스템은 오존 단독 처리 외에 OH라디칼의 생성조건을 조사하기위해 pH를 5에서 염기성 영역인 9까지 변화시켰으며, OH라디칼 생성 촉진제인 $H_2O_2$를 5-15 mg/L의 농도로, 그리고 OH라디칼 소거제로서 작용하는 $HCO_3{^-}$는 20-100 mg/L로 변화시키면서 처리하였다. 각 반응 조건에 따른 부식만의 분해특성을 살펴본 결과, TOC 제거율은 주로 0H라디칼에 의한 간접반응의 영향을 받았으며, $UV_{254}$ 감소율은 주로 오존분자와의 직접반응에 의해 효율이 결정되는 반응 경로를 거치는 것으로 나타났다. 또한 오존소모량은 주로 용액의 pH, alkalinity 변화에 따른 영향을 많이 받았다.

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회분식 오존 공정에서 페놀의 분해 속도에 관한 연구 (A Study on the Decomposition Rate of Phenol in the Batch Type Ozonation)

  • 안재동;강동수
    • 한국환경보건학회지
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    • 제23권4호
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    • pp.127-132
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    • 1997
  • The characteristics of the ozone treatments of phenol were studied in a laboratory scale wastewater treatment system. The ozone treatment of wastewater was carried out in a batch-type reactor. The initial pH of wastewater(7-10), volumetric flow rate(1-2l/min) and ozone concentration(20~30 mg/l) of aerating gas were considereal as experimental variables in the ozone treatment. Phenol was decomposed easily by the ozone in a batch treatment, where the rate determining step was the COD removal that is decomposition of intermediates formed by the ozonation of phenol. Phenol decomposition and COD removal could be expressed by the first order reaction for the phenol concentration and COD, respectively. Rate constants of phenol decomposition and COD removal increased with the initial pH, volumetric flow rate and ozone concentration of aeration gas. Under the present experimental condition, their relationships could be given by for the phenol decomposition $k'=4.46\times 10^{-9}[pH]_o ^{3.94}[O_3]^{1.42}Q_{O3}^{1.57}$ for the COD removal $k=2.46\times 10^{-10}[pH]_o ^{5.19}[O_3]^{1.15}Q_{O3}^{1.19}$

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$Al_2O_3$ 세라믹 유전체 오존발생기의 방전면적 특성 (Discharge Area Characteristics of Ozonizer with $Al_2O_3$ Dielectric)

  • 박현미;송현직;이상근;임창호;윤병한;김종현;이광식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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    • pp.2214-2216
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    • 2005
  • This paper is researched discharge and ozone generation characteristics of ozonizer using $Al_2O_3$ Ceramic dielectric. The discharge characteristics with variation of the discharge electrode area is studied. The characteristics of ozone concentration. ozone generation and ozone yield were measured to discharge power, discharge electrode area and supplied gas flux for oxygen and air. The solubility of ozone for water concentrations and ozone generations proportional to discharge power and discharge electrode area. Ozone yield has slowly increase with Increasing discharge power at high flow-rate. As the result, the maximum values of ozone characteristics ozone generation and ozone yield, can be obtained 5817[ppm] and 36[g/kWh]. We make enough the ozone concentration as the air in the home. An electric discharge electrode area is apt to shrink gradually into a miniaturization trend of the ozonizer but the enlargement of the occurrence flight of the electric discharge area gives the characteristic enhance the aid in the identity condition through the structure improvement.

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