• Asian Journal of Atmospheric Environment
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• v.7 no.3
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• pp.129-138
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• 2013

The water uptake by fine aerosol in the atmosphere has been investigated at Gosan, Korea during ABC-EAREX 2005. The concentration of inorganic ion and carbon components, size distribution, and light scattering coefficients in normal and dry conditions were simultaneously measured for $PM_{2.5}$ by using a parallel integrated monitoring system. The result of this study shows that ambient fine particles collected at Gosan were dominated by water-soluble ionic species (35%) and carbonaceous materials (18%). In addition, it shows the large growth of aerosol in the droplet mode when RH is higher than 70%. Size distribution of the particulate surface area in a wider size range ($0.07-17{\mu}m$) shows that the elevation of RH make ambient aerosol grow to be the droplet mode one around $0.6{\mu}m$ or the coarse mode one, larger than $2.5{\mu}m$. Hygroscopic factor data calculated from the ratio of aerosol scattering coefficients at a given ambient RH and a reference RH (25%) show that water uptake began at the intermediate RH range, from 40% to 60%, with the average hygroscopic factor of 1.10 for 40% RH, 1.11 for 50% RH, and 1.17 for 60% RH, respectively. Finally, average chemical composition and the corresponding growth curves were analyzed in order to investigate the relationship between carbonaceous material fraction and hygroscopicity. As a result, the aerosol growth curve shows that inorganic salts such as sulphate and nitrate as well as carbonaceous materials including OC largely contribute to the aerosol water uptake.

• Journal of Korean Society on Water Environment
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• v.18 no.3
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• pp.291-301
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• 2002

In this study, nutrients treatment by sequencing batch reactors(SBR) was performed. Nitrogen and phosphorus removal efficiencies were evaluated by changing SRT and mixing/aeration ratio. Not only nitrogen but also phosphorus removal patterns were investigated through track studies on 1 cycle. As SRT was fixed and mixing/aeration ratio was changed, maximum nitrogen removal efficiency was 87.6% at mixing/aeration ratio 0.67. Phosphorus removal efficiencies were more than 85.5% except no mixing condition. As mixing/aeration ratio was fixed and SRT was changed, nitrogen removal efficiencies were 70.5~79.8%, which represented slight changes, while phosphorus removal efficiencies were 49.0~97.3%, which represented sharply decreasing tendency at less than 20 day. Both phosphorus release rate k and maximum phosphorus release rate $P_{max}/M$ were are decreased as SRT was decreased, but they were not affected by mixing/aeration ratio. It was found that there is a linear relationship between ortho-phosphate uptake and maximum ortho-phosphate release.

• Membrane and Water Treatment
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• v.6 no.4
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• pp.263-276
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• 2015

This paper deals with the influence of chemical oxygen demand to nitrogen ratio ((COD/N) ratio) on the performance of an membrane bioreactor. We aim at establishing relations between COD/N ratio, organisms' distribution and sludge properties (specific resistance to filtration (SRF) and membrane fouling). It is also essential to define new criteria to characterize the autotrophic microorganisms, as the measurements of apparent removal rates of ammonium seem irrelevant to characterize their specific activity. Two experiments (A and B) have been carried on a 30 L lab scale membrane bioreactor with low COD/N ratio (2.3 and 1.5). The obtained results clearly indicate the role of the COD/N ratio on the biomass distribution and performance of the membrane bioreactor. New specific criteria for characterising the autotrophic microorganisms activity, is also defined as the ratio of maximum ammonium rate to the specific oxygen uptake rate in the endogenous state for autotrophic bacteria which seem to be constant whatever the operating conditions are. They are about 24.5 to 23.8 $gN-NH_4{^+}/gO_2$, for run A and B, respectively. Moreover, the filterability of the biological suspension appear significantly lower, specific resistance to filtration and membrane fouling rate are less than $10^{14}m^{-2}$ and $0.07\;10^{12}m^{-1}.d^{-1}$ respectively, than in conventional MBR confirming the adv < antage of the membrane bioreactor functioning under low COD/N ratio.

• Textile Coloration and Finishing
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• v.13 no.2
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• pp.42-42
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• 2001

Following the prior studs regarding that 1.0g of cotton fabric cound be dyed uniformly with a reactive dye in the solvent mixture of 2㎖ of water and 23㎖ of dichloromethane, silk fabric was dyed with C. I. Reactive Blue 203 in the water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only 3㎖ of water in 22㎖ of dichloromethane, 1.0g of silk fabric could be dyed perfectly. The uptake ratio was increased greatly, compared with that of normal reactive dyeing in a water medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the even dyeing as it disperses a small amount of dye-dissolved water phase and conveys this water phase to the fabric entirely and uniformly.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.9
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• pp.630-635
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• 2011

As this study was estimation of factors of rapid OUR (Oxygen Uptake Rate) monitoring method. Experiment for estimating factors of optimal microorganism activity was carried out in this study. In addition to comparison and estimation of SCOD variation by OUR variation using real wastewaters. In consequence OUR value was highest when F/M ratio, pH and temperature were 0.03~0.05, 6.0~8.5 and $20{\sim}30^{\circ}C$ respectively. Oxygen consumption by nitrification was incomplete. OUR variation of SCOD was recognizable difference of degradable rate at before and after of inflection point OUR. This study used an experimental method for real time prediction of the influent of the sewage treatment plant for optimal operation is expected to be able to do.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.1
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• pp.67-76
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• 2022

We developed a technology that can measure the hydrogen uptake and diffusivity of rubber materials by using the volumetric analysis method and diffusivity analysis program through the measurement of the water level in the graduated cylinder. In this method, hydrogen gas is charged at a certain pressure for a certain period of time for a rubber material exposed to a high-pressure hydrogen gas environment, and then the pressure is reduced to measure the change in the water level in the graduated cylinder in real time, and based on the measured value, it is a technology that can evaluate hydrogen uptake and diffusivity using diffusivity analysis program. Using this method, the hydrogen uptake and diffusivity of the NBR material were measured with respect to the change in the type and weight ratio of the filler used to improve the physical properties of the rubber material. In addition, uncertainty analysis was performed on the diffusivity measurement method.

• Textile Coloration and Finishing
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• v.13 no.2
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• pp.128-134
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• 2001

Following the prior studs regarding that 1.0g of cotton fabric round be dyed uniformly with a reactive dye in the solvent mixture of $2m\ell$ of water and $23m\ell$ of dichloromethane, silk fabric was dyed with C. I. Reactive Blue 203 in the water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only $3m\ell$ of water in $22m\ell$ of dichloromethane, 1.0g of silk fabric could be dyed perfectly. The uptake ratio was increased greatly, compared wish that of normal reactive dyeing in a water medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the Even dyeing as it disperses a small amount of dye-dissolved phase and conveys this water phase to the fabric entirely and uniformly.

• Textile Coloration and Finishing
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• v.13 no.1
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• pp.55-60
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• 2001

Cotton fabric was deed with a reactive dye in water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only 2ml of water in 23m1 of dichloromethane, 1.0g of cotton fabric could be dyed perfectly. The uptake ratio was increased greatly, compared with that of normal reactive dyeing in a waters medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the eden dyeing as it disperses a small amount of dye-dissolved water phase and conveys this water phase to the fabric entirely and uniformly.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.2
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• pp.144-149
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• 2017

A proton-conducting bisphenylpropaned sulfonated fluorinated blockcopolymer (BPSFBC) was synthesized. Five kinds of polymer electrolyted composite membranes were preparated by incorporating silica ($SiO_2$) with various weight ratio. And their characteristics were investigated by FT-IR (fourier transform infrared), $^1H-NMR$ ($^1H$ nuclear magnetic resonance), TGA (thermogravimetric analysis), water uptake, FE-SEM (field emission scanning electron microscopes), and ion conductivity properties. The water uptake and ion conductivity were increased until 9 wt% $SiO_2$, and then decreased. The maximum proton conductivity equal to $52mScm^{-1}$ was measured for the BPSFBC/$SiO_2$-9 composite membrane at $90^{\circ}C$ and 100% relative humidity. From the measured results, it is distinct that the manufactured composite membrane BPSFBC/$SiO_2$-9 can be considered as a polymer membrane suitable for a fuel cell electrolyte.

• The Korea Journal of Herbology
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• v.26 no.1
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• pp.81-85
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• 2011

Objective : This study was designed to investigate the effects of Angelicae Gigantis Radix (AGR) on Polycystic Ovary (PCO) induced by Estradiol valerate (EV) in female rats. Methods : We investigated the effects of AGR on Changes in body weights and food and water uptake for 5 weeks. In addition, we examined the effects on ovary weights. Finally, we also observed histopathological changes in PCO rats. Results : Treatment with AGR did not affect body weights, amount of food and water uptake. Administration group of AGR restored body/ovary weight ratio to normal levels, which were lowered by induction of PCO. In histopathological observation, formation of cysts was suppressed in AGR group compared with non-treated control group. Conclusion : These results suggest that AGR can be used for patients with PCO to prevent formation of cystic follicles and malfunction of ovary.