• Title/Summary/Keyword: water plasma

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A Study on ther Water Plasma Chemical Process Discharge by Pulse Power Supply (펄스전원을 이용한 수중플라즈마 방전에 관한 연구)

  • Shin, Wan-Ho;Hong, Won-Seok;Yoo, Hyo-Yol;Park, Sun-Soon;Choi, Jae-Ho
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2179-2181
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    • 2005
  • An experimental study on the water plasma characteristics of removal efficiency for organic contaminants in dye waste water has been investigated. In this study, dielectric barrier discharging electrodes with round shape have disposed cross each other in reactor, and pulse power was supplied to between each electrodes. Its output pulse voltage range is from 0[V] to 30[kV] and output frequency range is from 100[Hz] to 2[kHz]. Using proposed system, High frequency discharge is tested in the mixed Tone(air and water) and the space distribution of streamer corona plasma is observed. In spite of the increasement of voltage and frequency, the proposed system have a stable operation characteristics. It is verified by the experimental results.

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Optimization of Design of Plasma Process for Water Treatment using Response Surface Method (반응표면분석법을 이용한 수처리용 플라즈마 공정 설계의 최적화)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Korean Society on Water Environment
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    • v.27 no.5
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    • pp.617-624
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    • 2011
  • In order to confirm the creation of the OH radical which influences to RNO bleaching processes, it experimented using laboratory reactor of dielectric barrier discharge plasma (DBDP). The experiments performed in about 4 kind process variables (diameter of ground electrode, diameter of discharge electrode, diameter of quartz tube and effect of air flow rate) which influence to process. In order to examine optimum conditions of design factors as shown in Box-Behnken experiment design, ANOVA analysis was conducted against four factors. The actual RNO removal at optimized conditions under real design constraints were obtained, confirming Box-Behnken results. Optimized conditions under real design constraints were obtained for the highest desirability at 1, 1 mm diameter of ground and discharge electrode, 6 mm diameter of quartz tube and 5.05 L/min air flow rate, respectively.

Optimization of Air-plasma and Oxygen-plasma Process for Water Treatment Using Central Composite Design and Response Surface Methodology (중심합성설계와 반응표면분석법을 이용한 수처리용 산소-플라즈마와 공기-플라즈마 공정의 최적화)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
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    • v.20 no.7
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    • pp.907-917
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    • 2011
  • This study investigated the application of experimental design methodology to optimization of conditions of air-plasma and oxygen-plasma oxidation of N, N-Dimethyl-4-nitrosoaniline (RNO). The reactions of RNO degradation were described as a function of the parameters of voltage ($X_1$), gas flow rate ($X_2$) and initial RNO concentration ($X_3$) and modeled by the use of the central composite design. In pre-test, RNO degradation of the oxygen-plasma was higher than that of the air-plasma though low voltage and gas flow rate. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the RNO removal efficiency and test variables in a coded unit: RNO removal efficiency (%) = $86.06\;+\;5.00X_1\;+\;14.19X_2\;-\;8.08X_3\;+\;3.63X_1X_2\;-\;7.66X_2^2$ (air-plasma); RNO removal efficiency (%) = $88.06\;+\;4.18X_1\;+\;2.25X_2\;-\;4.91X_3\;+\;2.35X_1X_3\;+\;2.66X_1^2\;+\;1.72X_3^2$ (oxygen-plasma). In analysis of the main effect, air flow rate and initial RNO concentration were most important factor on RNO degradation in air-plasma and oxygen-plasma, respectively. Optimized conditions under specified range were obtained for the highest desirability at voltage 152.37 V, 135.49 V voltage and 5.79 L/min, 2.82 L/min gas flow rate and 25.65 mg/L, 34.94 mg/L initial RNO concentration for air-plasma and oxygen-plasma, respectively.

Effects of Surface Modification of the Membrane in the Ultrafiltration of Waste Water

  • Cho Dong Lyun;Kim Sung-Hyun;Huh Yang Il;Kim Doman;Cho Sung Yong;Kim Byung-Hoon
    • Macromolecular Research
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    • v.12 no.6
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    • pp.553-558
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    • 2004
  • An ultrafiltration membrane (polyethersulfone, PM 10) was surface-modified by treating it with low-tem­perature plasmas of oxygen, acrylic acid (AA), acetylene, diaminocyolohexane (DACH), and hexamethyldisiloxane (HMDSO). The effects that these modifications have on the filtration efficiency of a membrane in waste water treat­ment were investigated. The oxygen, AA, and DACH plasma-treated membranes became more hydrophilic. The water contact angles ranged from < $10^{\circ}\;to\;55^{\circ}$ depending on the type of plasma and the treatment conditions. The oxygen plasma-treated membranes displayed a higher initial flux $(312-429\%),$ but lower rejection $(6-91\%),$ than did an untreated membrane. The AA plasma-treated membranes displayed lower or higher initial flux $(42-156\%),$ depending upon the treatment conditions, but higher rejection $(224-295\%)$ in all cases. The DACH plasma-treated membranes displayed lower initial flux. All of them, especially the AA plasma-treated membrane, displayed improved fouling resistance with either a slower or no flux decline. Acetylene and HMDSO plasma-treated membranes became more hydrophobic and displayed both lower initial flux and lower fouling resistance.

Changes of Plasma and Hepatic Lipids, Hydroxy-Methyl-Glutaryl CoA Reductase Activity and Acyl-CoA : Cholesterol Acyltransferase Activity by Supplementation of Hot Water Extracts from Rosa rugosa, Crataegus pinnatifida and Polygonum cuspidatum in High-Cholesterol Fed Rats

  • Lee, Hee-Ja;Park, Myung-Sook
    • Preventive Nutrition and Food Science
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    • v.3 no.4
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    • pp.344-350
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    • 1998
  • Lipid lowering properties from three plant water extracts, Rosa rugosa, Crataegus pinnatifida and Polygonum cuspidatum, were tested by supplementing a 1% high-cholesterol diet with them in rats. Plasma triglyceride levels in Rosa fugosa, Crataegus pinnatifida and Polygonum cuspidatum groups were significantly lower compared to that of the control. by 29% , 24% and 47% respectively. hepatic trigylceride levels in Rosa rugosa and Crataegus pinnatifida groups were significantly lower compared to the control by 11% and 15% respectively. Hepatic HMG-CoA reductase activity in Rosa rugosa group was significantly greater compared to the control by 406%. Hepatic ACAT activity was significantly lower in Polygonum cuspidatum group compared to the control by 28%. by multiple regression results, only plasma cholesterol was associated significantly (p<0.05) with liver HMG-CoA reductase activity. Plasma cholesterol explained 12% of thevariance of the liver HMG-CoA redctase activity. In conclusion, we have showen that hot water extracts from Rosa rugosa, Crataegus pinnatifida and Polygonum cuspidatum lowered plasma triglycerides in rats fed on a high-cholesterol diet. Data suggests that these extracts could potentially prevent or treat hypertriglyceridemia induced by a high fat diet and fatty liver.

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Phenol Removal Using Oxygen-Plasma Discharge in the Water (산소-플라즈마 방전을 이용한 수중의 페놀 제거)

  • Park, Young-Seek
    • Journal of Environmental Science International
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    • v.22 no.7
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    • pp.915-923
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    • 2013
  • Decomposition of non-biodegradable contaminants such as phenol contained in water was investigated using a dielectric barrier discharge (DBD) plasma reactor in the aqueous solutions with continuous oxygen bubbling. Effects of various parameters on the removal of phenol in aqueous solution with high-voltage streamer discharge plasma are studied. In order to choose plasma gas, gas of three types (argon, air, oxygen) were investigated. After the selection of gas, effects of 1st voltage (80 ~ 220 V), oxygen flow rate (2 ~ 7 L/min), pH (3 ~ 11), and initial phenol concentration (12.5 ~ 100.0 mg/L) on phenol degradation and change of $UV_{254}$ absorbance were investigated. Absorbance of $UV_{254}$ can be used as an indirect indicator of phenol degradation and the generation and disappearance of the non-biodegradable organic compounds. Removal of phenol and COD were found to follow pseudo first-order kinetics. The removal rate constants for phenol and COD of phenol were $5.204{\times}10^{-1}min^{-1}$ and $3.26{\times}10^{-2}min^{-1}$, respectively.

Surface Modification of TiO2 by Atmospheric Pressure Plasma (대기압 플라즈마를 이용한 TiO2 광촉매의 효율향상을 위한 표면 개질 연구)

  • Cho, S.J.;Jung, C.K.;Kim, S.S.;Boo, J.H.
    • Journal of the Korean Vacuum Society
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    • v.19 no.1
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    • pp.22-27
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    • 2010
  • To improve surface wettability, each sample was treated by atmospheric pressure plasma (APP) using dielectric barrier discharge (DBD) system. Argon and oxygen gases were used for treatment gas to modify the $TiO_2$ surface by APP with RF power range from 50 to 200 W. Water contact angle was decreased from $20^{\circ}$ to $10^{\circ}$ with argon only. However, water contact angle was decreased from $20^{\circ}$ to < $1^{\circ}$ with mixture of argon and oxygen. Water contact angle with $O_2$ plasma was lower than water contact angle with Ar plasma at the same RF power. It seems to be increasing the polar force of $TiO_2$ surface. Also, analysis result of X-ray photoelectron spectra (XPS) shows the increase of intensity of O1s shoulder peak, resulting in increasing of surface wettability by APP. Moreover, each water contact angle increased according to increase past time. However, contact angle increase with plasma treatment was lower than without plasma treatment. Additionally, the efficiency of $TiO_2$ photocatalyst was improved by plasma surface-treatment through the degradation experiment of phenol.

Plasma Cosmetic Container Suitability (플라즈마 화장품 용기 적합성)

  • Ha Hyeon Jo;You-Yeon Chun;Hyojin Heo;Sang Hun Lee;Lei Lei;Ye Ji Kim;Byeong-Mun Kwak;Mi-Gi Lee;Bum-Ho Bin
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.50 no.1
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    • pp.59-65
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    • 2024
  • For plasma cosmetics, it is important to ensure the long-term stability of plasma in the formulation. This study examined the suitability of containers for efficient plasma cosmetics development. By varying the surface area covered by the plasma, 4 cm2, 25 cm2, 75 cm2, and 175 cm2 containers were injected with cosmetic plasma, and the amount of nitric oxide (NO), the main active species of nitrogen plasma, was analyzed. As a result, the surface area and stability exposed to plasma tended to be inversely proportional, and it was most effective in a 4 cm2 container. Furthermore, 25 mm, 40 mm, and 50 mm vials were treated with plasma, which resulted in relative long-term stability of NO at 25 mm, a smaller surface area of the container exposed to air. Water mist and stratified mist were selected as cosmetic formulations, and NO plasma was injected into the water layer to observe the changes in formulation properties and the state of the injected NO plasma. In both formulations, the amount of NO plasma injected was about 1.5 times higher in the water phase mist than in the stratified mist, and the stratified mist gradually decreased with time and was found to disappear after 3 weeks. The stability of the nitrogen plasma was studied at low temperature (4 ℃), room temperature (25 ℃), and high temperature (37 ℃, 50 ℃). As a result, it was found that the water mist did not affect the stability, but the stratified mist observed a color change in the oil phase layer. Overall, this study demonstrates the container suitability of nitrogen plasma and suggests the importance of ensuring the stability of injected nitrogen plasma in cosmetic formulations.

Characteristics of ZnO Thin Films by Means of ALD for the Application of Transparent TFT

  • ParkKo, Sang-Hee;Hwang, Chi-Sun;Kwack, Ho-Sang;Kang, Seung-Youl;Lee, Jin-Hong;Chu, Hye-Yong;Lee, Yong-Eui
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1564-1567
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    • 2005
  • Zinc oxide thin films were grown at the t emperature of $100^{\circ}C$ and $150^{\circ}C$ by means of plasma enhanced atomic layer deposition (PEALD) and conventional atomic layer deposition for applying to the transparent thin film transistor (TTFT). The growth rate of $1.9{\AA}/cycle$ with oxygen plasma is similar to that of film grown with water. While the sheet resistivity of ZnO grown with water is 1233 ohm/sq, that of film grown with oxygen plasma was too high to measure with 4 point probe and hall measurement system. The resistivity of the films grown with oxygen plasma estimated to be $10^6$ times larger than that of the films grown with water. The difference of electrical property between two films was caused by the O/Zn atomic ratio. We fabricated ZnO-TFT by means of ALD for the first time and the ZnO channel fabricated with water showed saturation mobility of $0.398cm^2/V{\cdot}s$ with bottom gate configuration.

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Effect of Choakwiyeum and Yukmijihwang-tang Water Extract on the Renal Aldosterone Concentration in Rabbits (좌귀음과 육미지황탕 전탕액 투여가 가토신기능 및 혈장 Aldosterone농도에 미치는 영향)

  • Choi Woo Jung;Lee Eon Jeon;Kim Hyeong Kyun;Lee Kwang Suk;Lee Dae Young;Jung Dae Young
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.6
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    • pp.1263-1269
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    • 2002
  • To evaluate the effect of Choakwiyeum(CKY) and Yukmijihwang-tang(YJT) water extract on the renal function and the levels of plasma aldosterone, this experiment was performed in the rabbbits. These result indicate that increase in urine volume(UV) after administration of CKY and YJT water extract is related to increase in glomerular filtration rate(GFR), free water clearance(FWC) and renal plasma f1ow(RPF) and also to decrease in plasma aldosterone concentration(PAC), which seems to be affected by renin-angiotensin-aldosterone system, and that reduced blood pressure seems to be caused by reduced peripheral resistance.