• Title/Summary/Keyword: Effective Concentration

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A Study on the Reduction of Volatile Organic Compounds by Fatsia japonica and Ardisia pusilla (팔손이와 산호수에 의한 휘발성유기화합물 저감효과에 관한 연구)

  • Song, Jeong Eun
    • KIEAE Journal
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    • v.12 no.4
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    • pp.77-82
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    • 2012
  • This study conducted the experiment of reduction of Volatile Organic Compounds(VOCs) and Formaldehyde concentration by Native plants, Fatsia japonica and Ardisia pusilla. The two plants are advantageous in that they are highly available as they grow wild, and being easy to get. Fatsia japonica is a plant of its wide and large leaf diverged 7 or 8 parts, which is thought to have a high effect of air purification. Ardisia pusilla has a smaller leaf than Fatsia japonica, which is characterized by more leaves and beautiful. Field measurements were performed using Fatsia japonica and Ardisia pusilla which were verified as air-purifying plants in Korea. The effect of reducing the concentration of VOCs and Formaldehyde by plant studied in a full scale mock-up model. The dimensions of the two models were equal. The concentration of Benzene, Toluene, Ethylbenzene, Xylene, Stylene, Formaldehyde were monitored, since they were known as most toxic materials. The concentration of VOCs was monitored three hours after the plants were placed and three days after the plants were placed. Field measurements were performed in models where the plants were placed and were not. As a result, they had all an effect of reducing pollution. In all cases of experiment of planting and growing volume, the more planting volume, the more excellent the effect. Toluene was more effective in Fatsia japonica and Ardisia pusilla planted, Formaldehyde was more effective in Fatsia japonica planted respectively. In planting and growing and placing experiment, the placement at sunny spot was more effective than that at scattered growing. When Fatsia japonica was placed at sunny spot, the reduction effect of Formaldehyde was the most excellent, and when Ardisia pusilla was placed at sunny spot, the reduction effect of Toluene was the most effective.

Characterization of Heterogeneous Interaction Behaviour in Ternary Mixtures by Dielectric Analysis: The H-Bonded Binary Polar Mixture in Non-Polar Solvent

  • Sengwa, R.J.;Madhvi;Sankhla, Sonu;Sharma, Shobha
    • Bulletin of the Korean Chemical Society
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    • v.27 no.5
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    • pp.718-724
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    • 2006
  • The heterogeneous association behaviour of various concentration binary mixtures of mono alkyl ethers of ethylene glycol with ethyl alcohol were investigated by dielectric measurement in benzene solutions over the entire concentration range at 25 ${^{\circ}C}$. The values of static dielectric constant $\epsilon_0$ of the mixtures were measured at 1 MHz using a four terminal dielectric liquid test fixture and precision LCR meter. The high frequency limiting dielectric constant $\epsilon_\infty$ values were determined by measurement of refractive index $n_D$ ($\epsilon_\infty\;=\;n_D\;^2$). The measured values of $\epsilon_0$ and $\epsilon_\infty$ were used to evaluate the values of excess dielectric constant $\epsilon^E$, effective Kirkwood correlation factor $g^{eff}$ and corrective correlation factor $g_f$ of the binary polar mixtures to obtain qualitative and quantitative information about the H-bond complex formation. The non-linear behaviour of the observed $\epsilon_0$ values of the polar molecules and their mixtures in benzene solvent confirms the variation in the associated structures with change in polar mixture constituents concentration and also by dilution in non-polar solvents. Appearance of the maximum in $\epsilon^E$ values at different concentration of the polar mixtures suggest the formation of stable adduct complex, which depends on the molecular size of the mono alkyl ethers of ethylene glycol. Further, the observed $\epsilon^E$ < 0 also confirms the heterogeneous H-bond complex formation reduces the effective number of dipoles in these polar binary mixtures. In benzene solutions these polar molecules shows the maximum reduce in effective number of dipoles at 50 percent dilutions. But ethyl alcohol rich binary polar mixtures in benzene solvent show the maximum reduce in effective number of dipoles in benzene rich solutions.

Effect of Chlorination on Removal of Cyanobacterial Microcystins

  • Jung, Jong-Mun;Park, Hong-Ki;Lee, You-Jung;Jung, Eun-Young;Kwon, Ki-Won;Shin, Pan-Se;Joo, Gea-Jae
    • Journal of Environmental Science International
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    • v.11 no.11
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    • pp.1157-1163
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    • 2002
  • The effective removal of microcystins by chlorination was investigated on a laboratory scale. With an initial chl.a concentration of more than 1,000 $\mu\textrm{g}$/ℓ, the required chlorine dose for the effective removal of microcystins from the raw water was more than 8.0 mg/ℓ. Whereas, a chlorine dose of 3.0 mg/ℓcould effectively remove microcystins from raw water containing a chl.a concentration of less than 1,000 $\mu\textrm{g}$/ℓ. The microcystin removal was more effective below pH 8.0, plus the optimum pH range was unrelated to the concentration of toxic algal material. Although chlorination is one of the most effective methods for reducing the toxin from blue-green algae, it causes cell lysis and toxin release. However, it was demonstrated that the released cell lysates and toxins could be effectively removed by a higher dose of the oxidant. The highest removal efficiency of dissolved microcystins(initial concentration: 280 $\mu\textrm{g}$ L$\^$-1/) was with a chlorine dose of 5.0 mg/ℓ.

A Study on the Ethanol Concentration by Osmotic Sink Reverse Osmosis Process (Osmotic Sink Reverse Osmosis Process를 이용한 에탄올의 농축특성에 관한 연구)

  • 이광현;민병렬
    • Membrane Journal
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    • v.2 no.1
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    • pp.33-48
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    • 1992
  • OSRO process was developed and it was confirmed more effective in ethanol concentrating process comparing to reverse osmosis process. It may be industrialized if more effective membrane for OSRO and reverse osmosis, which indicate the value greater than zero, it was shown that OSRO process was more effective than reverse osmosis for the ethanol concentration process. The decrease of feed concentration and flow rate and the increase of applied pressure made more effective operating conditions in OSRO process to concentrate ethanol. From the numerical esults for the multi-plates, theoretical DC values of reverse osmosis and OSRO process was increased as the umber of stages increased. DC values were increased with the increase of applied pressure in same number of stages. The theoretical values of DC by numerical calculation were corresponded to the experimental values within 15% tolerance. DC value was increased proportional to applied pressure and osmotic sink solution flow rate but it was decreased proportional to feed concentration and flow rate. The numerical calculation over the wide ranges inclading experimental condition was proposed in this study.

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Improvement of Water Resistant Properties of a Linerboard for Corrugated Fiberboard Box by Coating with Na-alginate (알긴산 코팅에 의한 골판지 상자 제조용 라이너 원지의 수분저항성 증진)

  • Kim, Eun-Jung;Rhim, Jong-Whan;Kim, Byung-Yong
    • Korean Journal of Food Science and Technology
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    • v.38 no.6
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    • pp.762-766
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    • 2006
  • To improve water resistance of paperboard used to manufacture the corrugated boxes, effect of surface coating of the liner- board with Na-alginate was investigated by determining the optimum processing conditions such as a optimum alginate concentration for surface coating, plasticizer content, concentration of divalent cations their immersion times, For the surface coating of the liner-board, 2.5% Na-alginate solution was found to be the optimum concentration, and the concentration of glycerol used as plasticizer was effective when 35% alginate concentration was use was Used Immersion of the alginate coated paperboard for 3 min in a $CaCl_2$ solution improved the water resistance properties. As a divalent cation for the insolubilization of the alginate films, $Cu^{2+}$ was found to be as effective as $Ca^{2+}$. Among the platicizers tested, sorbitol was the most effective in reducing water vapor permeability and water solubility of alginate coated paperboard.

Effect of Korean Native Plant Diet on Lipid Metabolism, Antioxidative Capacity and Cadmium Detoxification in Rats (한국 고유의 산채류 첨가 식이가 흰쥐의 지방 대사 및 항산화능과 Cadmium 제독에 미치는 영향)

  • 박진아
    • Journal of Nutrition and Health
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    • v.32 no.4
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    • pp.353-368
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    • 1999
  • This study was performed to investigate the effects of Korean native plant diets on lipid and cadmium (Cd) metabolisms and also antioxidative enzyme activities in rats. Seventy male Sprague-Dawley rats weighing 210.3$\pm$2.7g were blocked into ten groups according to body weight. Rats were raised for four weeks with diets containing 0 or 0.04%(w/w) cadmium chloride and 5%(w/w) plant powder-Ssook(Artemisia princeps var. orientalis HARA), Chamchwi(Aster scaber THUNB), Gomchwi(Lingularia fischeri TUBCZ). or Solbeerum (Portulaca oleracea LINNE). Food intake, weight gain, food efficiency ratio, and weights of liver, kidney, spleen and epididymal fat were significantly lower in Cd-exposed groups, food efficiency ratio, and weights of liver, kidney, spleen and epididymal fat were significanlty lower in Cd-exposed groups. Plasma total lipid level, liver total lipid, cholesterol and triglycerde concentrations, and fecal total lipid, cholesterol and triglyceride excretions were decreased by Cd administration. Total lipid and triglyceride concentration in plasma and liver were lower in Chamchwi groups together with increased fecal total lipid and triglyceride excretions. Cholesterol concentration in plasma and liver were lower in Gomchwi groups with increased fecal cholesterol excretions. Activities of red-blood-cell superoxide dismutase(SOD), and liver catalase, SOD and glutathione peroxidase (GSH-px) were decreased significantly by Cd administration. Thiobarbituric acid reactive substance(TBARS) concentrations of plasma and liver were increased by Cd administration. Thiobarbituric acid reactive substance(TBARS) concentration of plasma and liver were increased by Cd administration. Administration of plant diets decreased plasma and liver catalase, SOD and GSH-px activities in Cd-free diet groups and increased them in Cd-administered groups. Plasma and liver TBARS concentrations were decreased in animals fed plant diets, with Chamchwi showing the most effective antioxidative capacity. The concentration of Cd accumulated in blood and tissue decreased in Cd-exposed groups fed plant diets. Liver Cd concentration were lower in the Chamchwi and Gomchwi groups, and kidney Cd levels were lower in the Ssook and Chamchwi groups. Among them, Chamchwi was the most effective in Cd detoxification. In conclusion, Chamchwi and Gomchwi were effective in lowering tissue lipid levels, with Chamchwi having the greatest antioxidative and detoxifying effects.

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Dependence of Ozone Generation in a Micro Dielectric Barrier Discharge on Dielectric Material and Micro Gap Length

  • Sakoda, Tatsuya;Sung, Youl-Moon
    • KIEE International Transactions on Electrophysics and Applications
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    • v.4C no.5
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    • pp.201-206
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    • 2004
  • In order to investigate the optimum conditions for the effective ozone formation in a dielectric barrier discharge, measurements of ozone concentration were carried out for various conditions such as the gap length, the dielectric material and the operating gas. It was found that the optimum discharge conditions differed exceedingly in the types of operating gases and dielectric materials. In dry air, dielectric material with low dielectric constant and thermal conductivity, which might contribute to the restriction of the gas temperature rise in the discharge region, proved effective in obtaining both high ozone yield and concentration. The optimum gap length was considered to be in the range of 600-800 mm. In oxygen, using a quartz glass disk as a dielectric material, the required condition to obtain the high ozone yield and concentration was expanded.

Effects of Cadmium on Radial Growth and Dry Mass Production of Ectomycorrhizal Fungi

  • Kim, Chang-Gi;Power, Sally Anne;Bell, John Nigel Berridge
    • The Korean Journal of Ecology
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    • v.27 no.5
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    • pp.301-306
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    • 2004
  • The sensitivity to Cd of three ectomycorrhizal fungi, Paxillus involutus, Suillus bovinus and Rhizopogon subcaerulescens, was assessed and compared in terms of radial growth and dry mass production, using both agar and liquid culture. The radial growth of S. bovinus and R. subcaerulescens was significantly reduced at the lowest concentration (0.1mg Cd/L). The 50% effective concentration (EC$_{50}$) values calculated from radial growth rates of the ectomycorrhizal fungi showed that the sensitivity of the fungi to Cd was greatest in S. bovinus and lowest in R. subcaerulescens. Cadmium addition also significantly decreased dry mass production of the ectomycorrhizal fungi. The sensitivity of the fungi to Cd in terms of dry mass production, was greatest in S. bovinus and lowest in P. involutus. Higher growth rates of P. involutus and melanisation of R. subcaerulescens appeared to contribute to reduced Cd toxicity.

A Numerical Simulation of High Ozone Episode Using OZIPR in Busan (OZIPR을 이용한 부산지역 고농도 오존 사례 모사)

  • Do, Woo-Gon;Lee, Hwa-Woon;Jung, Woo-Sik
    • Journal of Environmental Science International
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    • v.16 no.8
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    • pp.985-994
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    • 2007
  • To investigate the effect of NOx and VOCs(volatile organic compounds) on the generation of high ozone episode, examined the hourly variations of ozone, NOx and VOCs concentrations, and calculated the ozone isopleth about maximum ozone concentrations using OZIPR which was presented by U. S. EPA at three sites in Busan. There was some difference by the sites, but decreasing VOCs concentration was effective for reduction of ozone at 22 July, the episode day of 2005. In the year 2006, the episode day was 8 August and the variations of NOx and VOCs concentration was little than variation of ozone. So it was estimated that the photochemical production of ozone was low than transportation of ozone. And the result of the OZIPR modeling was that decreasing VOCs concentration was effective for reduction of ozone.

Effect of Sodium Chloride on Stress-Deformation of Sand Bentonite Mixture (염분이 모래와 벤토나이트 혼합토의 응력 변형에 미치는 영향)

  • 안태봉
    • Geotechnical Engineering
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    • v.13 no.2
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    • pp.17-28
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    • 1997
  • In this study sodium chloride solution is employed for chemicals, and several cylindrical triaxial tests are performed on the sand-bentonite mixtures saturated with sodium chloride solution. Deformation(elastic modulus, E) and strength(cohesion, c', and angle of friction, f') parameters are obtained from the triaxial tests as functions of confining pressure and sodium chloride solution concentrations. The results here indicate an increase in the value of effective cohesion with increase in the concentration of NaCl solution, which can be explained by using the Gouy-Chapman model. The value of the effective angle of shearing resistance does not show significant change with the increase in concentration of NaCl solution. The Young's modulus also increases with the increase in concentration of NaCl solution.

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