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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Chemical Engineering Research
Journal Basic Information
Journal DOI :
The Korean Institute of Chemical Engineers
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Volume & Issues
Volume 47, Issue 6 - Dec 2009
Volume 47, Issue 5 - Oct 2009
Volume 47, Issue 4 - Aug 2009
Volume 47, Issue 3 - Jun 2009
Volume 47, Issue 2 - Apr 2009
Volume 47, Issue 1 - Feb 2009
Selecting the target year
Characterization of Supported Lipid Layers Using Atomic Force Microscopy
Park, Jin-Won ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 395~402
The atomic force microscopy(AFM) has been used, as a powerful tool, to investigate physical properties of supported-lipid layers. Prior to the advent of the AFM, no observation was performed for the physical phenomena at the nanometer-scale. This microscope provides nanometer-scale morphology by scanning surfaces with the cantilever and presents force curve by monitoring the behavior of the cantilever that approaches to surface and retracts from the surface. From the morphology, the structures of the supported lipid layer and the effect of other molecules on the structures have been investigated. From the force curve, the surface properties–electrostatic and mechanical properties-of the supported lipid layers have been studied. In this article, characterization of the structure and surface properties of the supported lipid layer is explained. Future perspectives and direction are also discussed.
Cure Characteristics and Mechanical Properties of Ternary Accelerator System in NR/BR Compounds
Kim, Il-Jin ; Kim, Wook-Soo ; Lee, Dong-Hyun ; Bae, Jong-Woo ; Byon, Young-Hoo ; Kim, Won-Ho ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 403~409
In the 1840s, Goodyear found out sulfur cure system, but cure time was too slow. So producing of rubber product takes a long time. In 1904, Oenslager et al. found that aniline is accelerated sulfur cure system. Recently, many rubber industries needed high yield and good quality. So, many researchers have studied a rubber system with fast vulcanization time and good mechanical properties. In this study, cure characteristics and mechanical properties of NR/BR compounds by accelerator with MBTS(2,2' Dithiobisbenzothiazole), TMTM(Tetramethylthiuram Monosulfide), ZDMC (Zinc dimethyldithiocarbamate), CBS(N-Cyclohexyl benzothiazolyl-2-sulfenamide), DPG(Diphenylguanidine) were evaluated. The results of the study indicate that cure charateristics(
: 235 sec,
: 5.77 Nm) and mechanical properties (100, 300% modulus : 2,180, 5.656 Mpa and tear strength: 59.58 kgf/cm) of NR/BR compounds shows efficient acceleration with MBTS 1.5 phr, TMTM 0.5 phr, DPG 0.15phr. This is due to the synergistic activity of ternary accelerator system in rubber vulcanization.
Reaction Kinetics of Carbon Dioxide and Glycidyl Methacrylate using a Ionic Liquid Catalyst of Imidazole Immobilized on MCM41
Son, Young-Sik ; Park, Moon-Ki ; Kim, Gun-Woo ; Park, Sang-Wook ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 410~417
Carbon dioxide was absorbed into GMA solution in a stirred flat cell using mesoporous catalyst Imidazole-CP-MS41, which was synthesized by CP-MCM41 with imidazole. Experiments were carried out at a batch-type absorber with different conditions, varying reaction temperature, concentration of GMA, solvent but maintaining 50 rpm of agitation speed and 2 g of catalyst. Absorption rate of
was used to obtain the kinetics based on the film theory using zwitterion mechanism with 2 elementary reaction and the kinetics were correlated with the solubility parameter of the solvents.
Performance Characteristics of Organic Electroluminescence Diode Using a Carbon Nanotube-Doped Hole Injection Layer
Kang, Hak-Su ; Park, Dae-Won ; Choe, Young-Son ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 418~423
MWCNT(multi-wall carbon nanotube)-doped PEDOT:PSS(poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)), used as a HIL(hole injection layer) material in OLEDs(organic light emitting diodes), was spin-coated on to the ITO glass to form PEDOT:PSS-MWCNT nano composite thin film. Morphology and transparency characteristics of nano composite thin films with respect to the loading percent of MWCNT have been investigated using FT-IR, UV-Vis and SEM. Furthermore, ITO/PEDOT:PSS-MWCNT/NPD/
/Al devices were fabricated, and then J-V and L-V characteristics were investigated. Functional group-incorporated MWCNT was prepared by acid treatment and showed good dispersion property in PEDOT:PSS solution. PEDOT:PSS-MWCNT thin films possessed good transparency property. For multi-layered devices, it was shown that as the loading percent of MWCNT increased, the current density increased but the luminance dramatically decreased. It might be conclusively suggested that the enhanced charge mobility by MWCNT could increase the current density but the hole trapping property of MWCNT could dramatically decrease the hole mobility in the current devices.
Synthesis of Sodalite from Water Glass: Effect of the Composition of Synthetic Mixtures on Its Crystallinity and Crystallite Size
Bae, Song-Eun ; Seo, Gon ; Song, Mee-Kyung ; No, Kyoung-Tai ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 424~429
The effects of
contents of the synthetic mixtures prepared from water glass on the crystallinity and crystallite size of sodalite were studied. The composition of the synthetic mixtures described by x
was varied within x=2.5~7.5, y=1.4~3.0, z=140~400. The hydrothermal reaction was carried out at
for 2 days. High content of
resulted in the high crystallinity and small crystallite of sodalite. The
molar ratios of around 2 were suitable for the synthesis of sodalite, and produced zeolite species were varied by the H2O content. Sodalite was mainly obtained with a high crystallinity from the synthetic mixtures with
molar ratio of around 2 and high content of
. The high content of sodium ions caused a decrease in the particle sizes because of their role of structure directing agent.
Effect of Solvents on the Photochromic Properties of Spiropyran in Hard Coating Films Prepared by Sol-Gel Method
Kim, Dae-Hyun ; Shin, Yong-Tak ; Lee, Ju-Yeon ; Hong, Won-Gil ; Lee, Bum-Suk ; Song, Ki-Chang ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 430~435
Spiropyran-doped organic-inorganic hybrid coatings were prepared starting from glycidoxypropyl triethoxysilane and vinyltriethoxysilane by a sol-gel method. They were applied as a thin layer to polycarbonate sheets and their photochromic properties were investigated. The effect of polarity of solvents dissolving the spiropyran was investigated on the photochromic properties. The decoloration rate of the spiropyran decreased with increasing the polarity of solvents dissolving the spiropyran because the open form of the spiropyran was easily stabilized in the polar gel matrix.
by using Chemical Lung Containing Potassium Superoxide
Kim, Jin-Ho ; Jurng, Tae-Hoon ; Park, Yoon-Kook ; Jeong, Soon-Kwan ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 436~440
This study demonstrates the use of a chemical lung containing potassium superoxide to convert carbon dioxide in air to oxygen. In order to reduce its extremely high reactivity, potassium superoxide was first mixed with calcium hydroxide and then combined at various ratios with polysiloxane. Silicone polymer used here served as both a water repellent and the polymer matrix. In general, the amount of carbon dioxide captured as well as that of oxygen produced increased as the proportion of potassium superoxide in the chemical lung increased. FT-IR spectroscopy revealed that the Si-O bond in chemical lung appeared at 1,050
and absorbance of chemical lung containing higher amounts of silicone was higher than that of chemical lung containing lower amounts. These results indicate that such a chemical lung may also be a useful sorbent for other acid gases, such as sulfur oxides and nitrogen oxides.
Effect of Temperature on Electrochemical Degradation of Membrane in PEMFC
Lee, Ho ; Kim, Tae-Hee ; Son, Ik-Jae ; Lee, Jong-Hyun ; Lim, Tae-Won ; Park, Kwon-Pil ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 441~445
Effect of temperature on membrane degradation in PEMFCs was studied. After cell operation at different temperatures(60~90
) under accelerating degradation conditions(OCV, anode dry, cathode RH 65%) for 144 h, cell performance decreased from 12 to 35%. The results of FER in effluent water showed that this decrease in cell performance was caused by membrane degradation by the attack of
or oxygen radicals(·OH,
·) and that resulted in increase in gas crossover for radical formation. Radical formation on the electrode was confirmed by ESR. Activation energy of 66.2 kJ/mol was obtained by Arrhenius plot used to analyze the effect of temperature on membrane degradation. Increase of cell temperature enhanced gas crossover rate, radical formation rate and membrane degradation rate.
Comparison of Counter-Current Cooling and Pool Boiling System Through Modeling and Simulation of a Pilot-Scale Fixed bed Reactor for Dimethyl Ether(DME) Synthesis
Song, Dae-Sung ; Go, Jae-Wook ; Yoon, En-Sup ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 446~452
The behavior of a one-step fixed bed reactor which directly synthesizes dimethyl ether(DME) from Natural Gas was simulated. In the reactor, the prevention of the occurrence of hot spots which can cause deactivation of catalysts is pivotal, since methanol synthesis and dehydration reaction involved in the synthesis of DME are highly exothermic. Therefore, we simulated and compared performance of the reactor with counter-current cooling and pool boiling system that can be applied to a commercial plant. As a result, we found that counter-current cooling system is more effective in terms of CO conversion and DME productivity. However, pool boiling system can operate in a small temperature gradient that can decrease problems caused by hot spot. And, the system can operate in a safer range.
Synthesis of pH-Sensitive Hydrogel Nanoparticles in Supercritical Carbon Dioxide
Yang, Ju-Seung ; Ryu, Won ; Lee, Sang-Min ; Kim, Kyu-Sik ; Choi, Moon-Jae ; Lee, Young-Moo ; Kim, Bum-Sang ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 453~458
Recently, new methods to synthesize and process polymers without toxic organic solvents are needed in order to solve environmental problems. The use of supercritical carbon dioxide as a solvent for the polymer synthesis is attractive since it is non-toxic, non-flammable, naturally abundant, and the product may be easily separated from the solvent. In this study, we developed the method using super critical
to prepare P(MAA-co-EGMA) hydrogel nanoparticles as an intelligent drug delivery carrier. The effects of concentrations of PtBuMA-PEO as a dispersion stabilizer and AIBN as an initiator on the particle synthesis were investigated. When PtBuMA-PEO concentration increased, the particle size decreased. However, there was no significant difference in the particle size according to the AIBN concentration. There was a drastic change of the equilibrium weight swelling ratio of P(MAA-co-EGMA) hydrogel nanoparticles at a pH of around 5, which is the
of PMAA. At a pH below 5, the hydrogels were in a relatively collapsed state but at a pH higher than 5, the hydrogels swelled to a high degree. In release experiments using Rh-B as a model solute, the P(MAA-co-EGMA) hydrogel nanoparticles showed a pH-sensitive release behavior. At low pH(pH 4.0) a small amount of Rh-B was released while at high pH(pH 6.0) a relatively large amount of Rh-B was released from the hydrogels.
Mass Transfer Characteristics in Pressurized Three-phase Slurry Bubble Columns with Variation of Column Diameter
Seo, Myung-Jae ; Lim, Dae-Ho ; Shin, Ik-Sang ; Son, Sung-Mo ; Kang, Yong ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 459~464
Gas-liquid mass transfer characteristics were investigated in pressurized three-phase slurry bubble columns with variation of column diameter. Effects of gas velocity, operating pressure, liquid viscosity, solid content in the slurry phase and column diameter on the gas-liquid volumetric mass transfer coefficient(
) were determined. The effects of operating variables on the mass transfer coefficient tended to change with variation of column diameter. The mass transfer coefficient increased with increasing gas velocity or operating pressure but decreased with increasing column diameter, liquid viscosity or solid concentration in the slurry phase. The increase trend of
value with increasing gas velocity and the decrease trend of
value with increasing liquid viscosity, tended to decrease gradually with increasing column diameter. However, the effects of operating pressure and solid concentration in the slurry phase on the
value did not change considerably with variation of column diameter. The values of
were well correlated with operating variables with in this experimental conditions as
Characteristic of Oxidation Reaction of Lanthanide Chlorides in Oxygen-Eutectic Salt Bubble Column
Cho, Yung-Zun ; Yang, Hee-Chul ; Lee, Han-Soo ; Kim, In-Tae ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 465~469
Characteristics of oxidation reaction of four lanthanide chlorides(Ce, Nd, Pr and
) in a oxygen-eutectic(LiCl-KCl) salt bubble column was investigated. From the results obtained from the thermochemical calculations by HSC chemistry software, the most stable lanthanide compounds in the oxygen-used rare earth chlorides system were oxychlorides(EuOCl, NdOCl, PrOCl) and oxides(
), which coincide well with results of the Gibbs free energy of the reaction. In this study, similar to the thermochemical results, regardless of the sparging time and molten salt temperature, oxychlorides for Eu, Nd and Pr and oxides for Ce and Pr were formed as a precipitant by a reaction with oxygen. The structure of the rare earth precipitates was divided into two shapes : small cubic(oxide) and large tetragonal (oxychloride) structures. The conversion efficiencies of the lanthanide elements to their molten salt-insoluble precipitates(or compound) were increased with the sparging time and temperature, and Ce showed the best reactivity. In the conditions of
of the molten salt temperature and 420 min of the sparging time, the conversion efficiencies were over 99% for all the investigated lanthanide chlorides.
Study of Emulsion Polymerization Condition of Aqueous Adhesive
Lee, Haeng-Ja ; Park, Ji-Sun ; Lee, Sang-Rok ; Kim, Jong-Min ; Chang, Sang-Mok ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 470~475
To study the optimal synthesis conditions of aqueous acrylic adhesive using emulsion polymerization, the effects of monomer, surfactant and initiator on the adhesive properties, such as conversion rate, particle size, peel strength, and glass transition temperature, were investigated. 2-EHA, n-BA and MMA were used as main monomers, 2-HEMA and AAc as functional monomers, SLS as surfactant and APS as initiator, respectively. The conversion rate was over 95% at 3.75% surfactant(SLS/monomer), 0.612% initiator(APS/monomer) and
reaction temperature. When the excess amount of surfactant or initiator was used, the peel strength represented decreasing tendency. The maximum conversion rate and peel strength were obtained at 65% 2-EHA/monomer, 20% BA/monomer, and 10% MMA/monomer.
Preparation and Electrochemical Behaviors of Polymer Electrolyte Based on PEO/PMMA Containing Li Ion
Han, A-Reum ; Park, Soo-Jin ; Shin, Jae-Sup ; Kim, Seok ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 476~480
A polymer composite electrolyte of a blend of poly(methyl methacrylate)(PMMA) and poly(ethylene oxide) (PEO) as a host polymer, the ethylene carbonate as a solvent, and
as a salt was studied. The crystallinity of the polymer electrolytes was evaluated using differential scanning calorimeter(DSC). The ionic conductivity of the polymer electrolytes was measured by frequency response analyzer(FRA) method. The effect of PEO/PMMA blend ratios on the ionic conduction in these electrolytes was investigated. The electrolyte films showed a phase separation due to immiscibility of the PMMA with the PEO. The PMMA-rich phase and the PEO-rich phase were produced during a film casting. The ionic conductivity of blend electrolyte was dependent on the content of PMMA and showed the highest value at 20 wt.%. However, when PMMA content exceeds 20 wt.%, the ionic conductivity was decreased due to the slow ionic transport through the PMMA-rich phase.
Flow Regime Transition in Air-Molten Carbonate Salt Two-Phase Flow System
Cho, Yung-Zun ; Yang, Hee-Chul ; Eun, Hee-Chul ; Kang, Yong ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 481~487
In this of study, effects of input air velocity(0.05~0.22 m/sec) and molten carbonate salt temperature (870~
) on flow regime transition have been studied by adopting a drift-flux model of air holdup and a stochastic analysis of differential pressure fluctuations in an air-molten sodium carbonate salt two-phase system(molten salt oxidation process). Air holdup where the flow regime transition begins was determined by air holdup-drift flux plot. The air holdup value which the flow regime transition begins was increased with increasing molten carbonate salt temperature due to the decrease of viscosity and surface tension of molten carbonate salt. To characterize the flow regime transition more quantitatively, differential pressure fluctuation signals have been analyzed by adopting the stochastic method such as phase space portraits and Kolmogorov entropy, The Kolmogorov entropy decreased with an increasing of molten carbonate salt temperature but increased gradually with an increase in an air velocity, however, it exhibited different tendency with the flow regime and the air velocity value which flow regime transition begins was same to the results of drift-flux analysis.
A Study on Synthesis Process of Zeolite 4A for Improvement of Properties as a Detergent Builder
Cho, Yong-Sik ; Lee, Won-Young ; Hong, Ji-Sook ; Suh, Jeong-Kwon ; Ryu, Seung-Kon ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 488~494
Zeolite 4A was prepared by new synthesis method, 2-step crystallization, for enhancement of oil absorption capacity. Vietnamese sand and
solution from natural bauxite were used as raw materials in stead of conventional cullet and Al
to reduced the processing cost. Some dissolved organics in
solution were removed by activated carbon. Synthetic method was progressed by 1) reacting the raw materials at
, 4 hr with the ratio of Si/Al to 1.15, and 2) reacting at
, 5 hr with reducing the ratio of Si/Al to 0.98. New method can easily control the particle size, aggregation, surface polarity, and enhanced the whiteness of the products. The prepared zeolite 4A shows excellent oil absorption capacity(O.A.C>50 ml/100 g) as well as equal value with calcium ion exchange capacity, and proves the 2-step crystallization is the economic and effective process for the preparation of zeolite 4A.
Adsorption Analysis of Benzene Vapor in a Fixed-Bed of Granular Activated Carbon
Kim, Seong-Soo ; Kim, Jong-Hyun ; Park, Sang-Wook ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 495~500
Activated carbon was used as an adsorbent to capture benzene vapor from gaseous stream of nitrogen in a fixed-bed to obtain the breakthrough data. The deactivation model is used to analyze the adsorption kinetics of benzene vapor using the experimental breakthrough data. The experimental breakthrough data are fitted very well to the deactivation model than the adsorption isotherm models in the literature.
Effect of Soluble EPCR on the Anti-Inflammatory Effects by Activated Protein C
Bae, Jong-Sup ; Park, Moon-Ki ; Park, Sang-Wook ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 501~505
In this study, we evaluated the effect of soluble EPCR(Soluble Endothelial Protein C Receptor, sEPCR) on the anti-inflammatory activities by activated protein C(APC) in endothelium. We demonstrated that sEPCR inhibited the barrier protective activity, the inhibition of neutrophils adhesion toward endothelial cells and the inhibition of transendothelial migration by APC in endothelial cells. Interestingly, sEPCR also blocked the mechanism by which APC inhibited the expression of cell adhesion molecules(CAM) by TNF-alpha in endothelial cells. These results suggested that the anti-inflammatory activities of APC was inhibited by sEPCR which blocked the binding motifs of Gla domain of APC to membrane bound EPCR. This finding will provide the important evidence in the development of new medicine for the treatment of severe sepsis and inflammatory diseases and good clue for understanding unknown mechanisms by which APC showed the anti-inflammatory activities in endothelium.
Production of Bacterial Cellulose by Gluconacetobacter hansenii Using a New Bioreactor Equipped with Centrifugal Impellers
Khan, Salman ; Shehzad, Omer ; Khan, Taous ; Ha, Jung-Hwan ; Park, Joong-Kon ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 506~511
In order to improve the bacterial cellulose(BC) production yield, centrifugal and inclined centrifugal impellers were developed. A 6 flat-blade turbine impeller was used as a control system. The flow pattern in the fermenter and volumetric oxygen transfer coefficient(k
a) of these fermentation systems were studied. Fermentations were carried out for the production of BC by G. hansenii PJK in a 2-L jar fermenter equipped with new impellers. Liquid medium was circulated from the bottom, through the cylinder of the impeller and to the wall. The volumetric oxygen transfer coefficients, k
a, of inclined centrifugal and centrifugal impeller systems at 100 rpm were 23 and 15% of the conventional turbine impeller system, respectively. However, the conversion of microbial cells to cellulose non-producing mutant decreased and this results in the increase in BC production at low rotating speed of impellers.
Study on the In-Furnace Desulfurization for Oxy-Fuel Combustion Flue Gases Using Drop Tube Furnace
An, Young-Mo ; Jo, Hang-Dae ; Choi, Won-kil ; Park, Yeong-Sung ; Keel, Sang-In ; Lee, Hyung-Keun ;
Korean Chemical Engineering Research, volume 47, issue 4, 2009, Pages 512~517
concentrations in oxy-fuel combustion flue gases increases about three times as high as that of conventional air combustion system owing to the flue gas recirculation for the control of combustion temperature. So the desulfurization reaction is different from that of the conventional air combustion system due to exceptionally high
concentration. In this study, drop tube furnace(DTF) system was used to investigate the desulfurization characteristics of limestone in oxy-fuel combustion furnace. The experiments were performed under
atmosphere to examine the effect of operating variables such as reaction temperatures, Ca/S ratios and inlet
concentrations on the
removal efficiency increased with reaction temperature, Ca/S ratio and inlet
concentration. And the addition of water vapor resulted in about 4~6% of increase in SO