• Title/Summary/Keyword: Nonaqueous

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Studies on the Preparation for the Simultaneous Removal of NO and $SO_2$ from Stationary Sources I.Surface properties and reactivity of $V_2O_5-MoO_3/TiO_2$ catalysts (고정원에서 배출되는 $NO_x/SO_x$의 동시제거를 위한 SCR 촉매의 제조법에 관한 연구: I. $V_2O_5-MoO_3/TiO_2$ 촉매들의 표면특성과 반응성)

  • 구미화;정석진
    • Journal of Korean Society for Atmospheric Environment
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    • v.8 no.1
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    • pp.58-67
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    • 1992
  • For removing $NO_x$ and $SO_x$ from the flue gases emitted from stationary sources, $V_2O_5-MoO_3/TiO_2$ catalysts were prepared by the conventional impregnation method (aqueous solution) and a sort of surface fixation method(nonaqueous solution) as reported excellent reproducibility catalysts. And these catalysts observed their catalytic activities as well as their surface properties. V-Mo-O oxide, prepared from nonaqueous solution of $VOCl_3$ and $Mo(CO)_6$ and aqeous solution method, was supported as amorphous state by XRD and SEM measurements. The infrared spectra of fresh and used catalysts showed that in used catalysts, V=O bands decreased and new bands of vanadium oxysulfate bands were very sensitive. So the catalysts prepared from nonaqueous solution may bring about the high activity. Results from catalytic activity measurements at 350$^\circ$C, in the presence of $SO_2, NO$ conversion was more increased than in absence of $SO_2$. As the $MoO_3$ was added to $V_2O_5/TiO_2 system, SO_2$ conversion increased. It found that from the results, $V_2O-5-MoO_3/TiO_2$ catalysts prepared from an nonaqueous solution may bring about the high activity for both the reaction of NO and $SO_2$ removal.

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Partitioning Tracer Analysis with Temporal Moments Equations (시간 모멘트식을 이용한 상분할추적자의 해석)

  • Cho, Jong-Soo
    • Journal of Soil and Groundwater Environment
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    • v.16 no.3
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    • pp.3-9
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    • 2011
  • Partitioning tracers have been used with non-partitioning, inert tracer such Br, for detection, estimation, and monitoring of remediation performance of the subsurface contaminated with nonaqueous phase liquids (NAPLs). Various partitioning tracers with different partition coefficients between aqueous and nonaqueous phase liquids can be used to determine the hydraulic conductivity, dispersivity, and residual mass of NAPLs in the subsurface soil matrices. Temporal moment-generating equations were used to analyze the field pilot-scale test results. The pilot-scale tests included conservative tracer tests and partitioning tracer tests. Analyses of nonaqueous phase liquid distribution and characteristics of groundwater bearing soil media were performed.

Preparation and Electric Double Layer Capacitance of Mesoporous Carbon

  • Shiraishi, Soshi;Kurihara, Hideyuki;Oya, Asao
    • Carbon letters
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    • v.1 no.3_4
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    • pp.133-137
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    • 2001
  • Mesoporous activated carbon fiber (ACF) was prepared from phenolic resin containing a small amount (0.1 wt %) of organic nickel complex through carbonization and steam activation. Microporous ACF as reference sample was also prepared from phenolic resin without agent. In both cases of the mesoporous ACFs and the microporous ACFs, the electric double layer capacitance of the nonaqueous electrolyte (0.5 M $TEABF_4$/PC or 1.0 M $LiClO_4$/PC) was not proportional to the BET specific surface area. This is owing to the low permeability of nonaqueous electrolyte or the low mobility of ion in narrow micropores. However, the mesoporous ACF showed higher double layer capacitance than the microporous (normal) ACF. This result suggests that the presence of many mesopores promotes the formation of effective double layer or the transfer of ion in the micropore.

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Stabilization of Ascorbic acid with Nonaqueous Emulsification (비수 유화법을 이용한 아스코르빅산의 안정화)

  • Lee, Chung Hee;Shin, Jae Dong;Bae, Su Hyun;Kang, Ki Choon;Pyo, Hyeong Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.4
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    • pp.263-270
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    • 2012
  • Ascorbic acid (Vitamin C) becomes unstable in the aqueous phase by oxygen, light and alkali, etc. The properties are limited in application to cosmetics. The most important factor that determines the destabilization of ascorbic acid in the aqueous phase was tried to understand considering its molecular deformation and degradation. In this study, we changed the polyols and emulsification technique for the stability of ascorbic acid. Then we observed the color and concentration change of ascorbic acid at room temperature and high temperature ($42^{\circ}C$) for 6 weeks and identified the stability using HPLC regularly. As a result, we found that glycerin was the most appropriate polyol for stability of the ascorbic acid. Also the technique of nonaqueous emulsification stabilized ascorbic acid than P/S emulsification. Also, P/S emulsification, glycerin was more stable than propylene glycol. By the results we suggest that ascorbic acid could be stabilized by nonaqueous emulsification method and this data could be applied to stabilization methods for cosmetic products.

Nano-capsulation of L-Ascorbic Acid in Nonaqueous System (L-Ascorbic Acid의 비수계 나노 캡슐화)

  • Hong, Joo-Hee;Song, Ki-Se;Kim, Kyoung-Jun;Lee, Chae-Seong;An, Byeong-Min;Kim, Byoung-Sik
    • Applied Chemistry for Engineering
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    • v.19 no.6
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    • pp.604-608
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    • 2008
  • In this work, the basic research for nano-capsulation of L-ascorbic acid (Vitamin C) in nonaqueous system was carried out. 500 nm-sized nano-capsules were prepared in nonaqueous system, and the emulsified capsule had mean size of 410 nm. The stability test on the temperature and the storage periods was performed at 4, 20, and $30^{\circ}C$ for 30 days. After 5 days, L-ascorbic acid was extricated 5.1, 9.3, and 12.5% at each temperature, but only 1~2 % was extricated after the time span. Likewise, the results of the skin susceptibility on women and men, each 10 persons, revealed that the very thin allergy was shown from only a woman after 2 days, but it was not shown from the others.

The Behavior of Solutes in Nonaqueous Solutions (Ⅱ). Relative Viscosities and Osmotic Coefficients of Urea, 1,3-Dimethylurea, Acetamide, and Propionamide (물아닌 용액에서의 용질의 행동에 관한 연구 (제2보). 요소, 1,3-디메틸요소, 아세트아미드와 프로피온아미드의 상대점도와 삼투계수)

  • Si-Joong Kim;Young-Kook Shin
    • Journal of the Korean Chemical Society
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    • v.24 no.3
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    • pp.209-217
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    • 1980
  • The relative viscosities and osmotic coefficients of solutions of urea, 1,3-dimethyl-urea(DMU), acetamide(AA), and propionamide (PA) in dimethylsulfoxide(DMSO), water, methanol, and in ethanol have been measured at 25 and $45^{\circ}$C by viscometry and osmometry. Viscosity increment in nonaqueous solutions decreased with increasing of the partial molal volumes of the solutes, but in aqueous solution the result was inversed. Viscosity increment of aqueous solution was smaller than that of aqueous DMU solution, but that of nonaqueous urea solution was larger than that of DMU. Amides, however, showed similar viscosity increment in any solvent.Osmotic coefficients of aqueous solution of urea were larger than those of DMU. In the nonaqueous solutions urea exhibited larger deviation from Raoult's law than DMU. The results indicated that urea molecules break water-structure in water, self-associate in DMSO, and showed larger solute-solvent interaction in alcohols than DMU. It can be also confirmed that amides break alcohol structure to a greater extent than any other solutes.

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Adsorption Mechanism of Solid Acid in Nonaqueous Solution (固體酸의 非水溶液에서의 吸着메카니즘에 관한 硏究)

  • Kwun, Oh-Cheun
    • Journal of the Korean Chemical Society
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    • v.9 no.4
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    • pp.185-189
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    • 1965
  • Korean acid clays and silica gel were put into action on benzene solution of dye, such as aniline yellow, o-nitro aniline and oil orange, and then the adsorptivity of dye in nonaqueous solution was measured, with the result that adsorptivity was greater with silica than acid clays and it had no relation to acidity. And when chemical compounds, such as amine, alcohol, halogen derivative, were added to each dye solution by 10%(in volume), the change of the adsorptivity of dye by solid acid(that is, the interfered adsorption rate) decreased in order of amine > alcohol > halogen derivative, and in homologue the smaller the molecular weight, the larger was the effect. So adsorption in nonaqueous solution was a selective adsorption of chemical compounds which contained negative groups such as amine and hydroxyl radicals, and it had no relation to surface tension and showed inverted phenomenon of Traube series. It is guessed that the inverted phenomenon (the interfered adsorption phenomenon) was due to the polar chemical adsorption between active $SiO_2$ which was an origin of solid acid and the adsorbed substances, considering that the order of inversion was nearly in accord with dipole moment of added solvents. The results of this study led to find adsorption mechanism and inverted phenomenon of Traube series in nonaqueous solution.

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Dispersion of Silicon Nitride Particles and Sintering Additives of AlN and Nd$_2$O$_3$ in Nonaqueous Suspending Media (비수계분산매체에서 질화규소와 소결첨가제 AlN 및 Nd$_2$O$_3$의 분산)

  • 김재원;백운규;윤경진
    • Journal of the Korean Ceramic Society
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    • v.36 no.2
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    • pp.210-219
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    • 1999
  • The fundamental dispersion property of Si2N4 and a combination of AlN and Nd2O3 as sintering additives in a variety of organic solvents such as alcohols, hydrocarbons, ketones, and ethers was investigated. The stabilization mechanism and interaction between organic functional groups of the various organic additives were studied to clarify the dispersibility of the ceramic particles in the nonaqueous suspending medium. characterization of the suspensions was based mainly on electrokinetic sonic amplitude(ESA) measurements and the flow curves obtained from the rheological studies as well as estimated Hamaker constants. It was found that the contribution of electrostatic repulsive forces to the Si3N4, AlN and Nd2O3 stabilization in organic media is appreciably greater than anticipated and is dependent on the physicochemical properties of organic solvents.

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