• 대한화학회지
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• 제14권1호
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• pp.97-107
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• 1970

액체 구조의 천이상태 이론을 써서 고체 표면에 기체가 흡착된 계에 대한 상태합을 유도하였다. 이 상태합을 써서 아르곤, 질소, 벤젠 등이 여러 가지 흡착제에 흡착되었을 때의 흡착등온 곡선을 계산하였으며, 이 계산 값들은 측정치와의 좋은 일치를 보여 준다. 그리고 벤젠이 흑연 표면에 흡착되었을 때의 표면압, 물엔트로피, 물에너지, 몰흡착열 들을 계산하였다. 몰엔트로피는 표면이 단분자층으로 완전히 덮였을 때 최소값을 갖는다. 아울러 흡착에 관여된 여러 가지 물리적인 성질들의 계산 방법을 설명하였다.

• 한국환경과학회지
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• 제14권7호
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• pp.691-697
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• 2005

Waste sludge may be used to recovery wastewater contaminated with heavy metals. The waste sludge is an inexpensive readily available source of biomass for biosorption with metal-bearing wastewater. The biosorption of heavy metals such as Pb(II), Cu(II), Cr(II), and Cd(II) onto waste sludge was investigated in batch ex­periments and waste sludge loaded heavy metals was separated by dissolved air flotation. The biosorption equi­bria of heavy metals could be described by Langmuir and Freundich isotherms. The adsorption capacity for waste sludge was in the sequence of Pb(II)>Cr(II)>Cu(II)>Cd(II). The system attained equilibrium about 20 min. The Langmuir and Freundlich adsorption model effectively described the biosorption equilibrium of Cu(II) and Cr(II) ions on waste sludge. Maximum adsorption capacity of Cu(II) and Cr(II) were 196.08 and 158.73 mg/g, respectively. Solid-liquid separation efficiencies were kept above $95\%$ on waste sludge loaded heavy metals, and were decreased with pH increasing.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.309-313
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• 2009

A micromechanical resonance sensor detects the resonance frequency shift due to mass or adsorption induced surface stress change during molecular adsorption or interaction on its surface. The resonance sensor is surrounded by gas or liquid solution during operation. To study the resonance shift phenomena depending on its surrounding environment, fluid-structure interaction of the resonance sensor has been analyzed for the different fluid environment and boundary conditions using finite element analysis.

• Carbon letters
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• 제4권2호
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• pp.64-68
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• 2003

A study on the electrosorption of uranium ions onto a porous activated carbon fiber (ACF) was performed to treat uraniumcontaining lagoon sludge. The result of the continuous flow-through cell electrosorption experiments showed that the applied negative potential increased the adsorption kinetics and capacity in comparison to the open-circuit potential (OCP) adsorption for uranium ions. Effective U(VI) removal is accomplished when a negative potential is applied to the activated carbon fiber (ACF) electrode. For a feed concentration of 100 mg/L, the concentration of U(VI) in the cell effluent is reduced to less than 1 mg/L. The selective removal of uranium ions from electrolyte was possible by the electrosorption process.

• Carbon letters
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• 제2권2호
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• pp.91-98
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• 2001

Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to $1000^{\circ}C$. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above $700^{\circ}C$ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.

• KSBB Journal
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• 제23권1호
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• pp.31-36
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• 2008

The use of L-carbohydrates and their corresponding nucleosides in medicinal application has greatly increased. For example L-ribose has been much in demand as the starting material for curing hepatitis B. High performance liquid chromatography (HPLC) method was studied for the analysis of ribose and arabinose fractions from ion exchange chromatography (IEC). Dowex Monosphere 99 Ca/320 resin was packed in IEC to separate ribose and arabinose under various operating conditions. $NH_{2}$ and sugar HPLC columns were then used to analyze the fractions from the IEC column. Pulse input method (PIM) was also used to measure adsorption isotherms of ribose and arabinose in the Dowex column and HPLC columns. Experimental results and simulations by ASPEN chromatography were compared with fair agreement.

• 한국응용과학기술학회지
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• 제12권2호
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• pp.115-120
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• 1995

Diazotization of 2-Amino-5-nitrophenol was Synthesized by the direct diazotization method. The diazonium salts are usually stabilized in the from of double salts. The double salts of zinc chloride are the Commonest, and the double salt method is Specially applicable to the yield-up of coupling. The azo dye(2-naphthol-1-(2'-diazo-5'-nitrophenol)) is Converted into a chromium Complex by heating($100^{\circ}C$) with chromic formate, and DMF. The removal of inorganic salts from dyestuffs was performed in DMF solvent. This effect was more pronounced. From these results, It was obtained to liquid dyestuffs of metal complex with High fastness and high adsorption.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1844-1850
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• 2006

Two types of catalyst samples were prepared, one sulfated zirconia and the other silica doped sulfated zirconia. The acidity tests indicate that sulfated zirconia doped with silica has higher concentration and strength of acidic catalyst sites than undoped sulfated zirconia. The acidic surface sites have been characterized using FTIR, NMR, pyridine adsorption, TPD, XRD and nitrogen adsorption. Doping with silica increased the concentration of surface Lewis and Brfnsted acid sites and resulted in generation of proximate acid sites.The activity test indicates that doping sulfated zirconia with silica increases both the acidity and catalytic activity for liquid phase dehydration of methanol at 413-453 K. Methanol is sequentially dehydrated to dimethyl ether and ethylene over both catalysts. Significant amounts of propylene are also formed over the silica-doped catalyst, but not over the undoped catalyst.

• Carbon letters
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• 제9권1호
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• pp.47-60
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• 2008

Understanding the exact structure and surface characteristics of carbon materials is very important for design, synthesis, and utilization of the best carbon form with particular functions and high performance for practical applications such as selective adsorption adsorbents, energy storage materials, catalysts or catalyst supports, etc. This review paper focuses on carbon surface properties and the interaction between gaseous or liquid substances and carbon surface. Catalytic functions of carbon materials are reviewed including recent progress in synthesis and applications of nano-carbons.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.353-353
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• 2010

Alcohol is a vesatile polar solvent for molecules. As a preparation to deposit large molecules, we studied interaction of solvent molecules on metallic surface. in this work, we report on methanol adsorption on NiAl(110) with scanning tunneling microscopy (STM). These alcohol solvent molecules were deposited by a pulse injection method suitable for deposition of thermally unstable molecules. The injection of liquid alcohol onto the substrate in UHV was performed by using a high-speed solenoid valve with the back-pressure reduced down to 100 Torr. This technique allowed precise control over the amount of dosing of molecules to less than 1 L. Alcohol-induced features, attributed to methoxy, were found on bare NiAl(110) surface.