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41.
Hoo Kun Lee Kwan Sik Chun Hyun Soo Park Jong Hyun Cho 《Korean Journal of Chemical Engineering》1989,6(4):294-299
A mathematical model for an absorption of nitrogen oxides into water in packed column was developed based on the mass-transfer
coefficient in packed column and the chemical reaction accompanying NO
x
absorption produces HNO3 and HNO2 in the liquid phase. The subsequent dissociation of HNO2 in the liquid-phase results in the formation of HNO3 and NO gas, and then this NO gas follows to be oxidized by O2 in air. The important factors influenced on the absorption of NO
x
are the oxidation state of NO gas and the partial pressure of nitrogen oxides in the gas. The efficiency of NO
x
absorption increases with the increase of the partial pressure of NO
x
. The most critical value for using the model is the constant of
.The selection of 11×10−4kg·mol/atm·m2·sec for
resonable for this model. 相似文献
42.
Soo‐kyung Shin Myung‐jin Jun Hyungki Hong 《Journal of the Society for Information Display》2014,22(2):122-128
In stereoscopic images, the crossing point of the viewing directions of the two eyes determines the perceived depth. Assuming that accommodation is affected by the positions of the crossing point, the effect of crossing point on minimum angle of resolution (MAR) was investigated. For 40 participants, MAR was measured by two‐alternative forced choice where Snellen optotype E of up and down directions were used as two kinds of stimuli. As the crossing point of the viewing direction of the left and right eyes moves farther from the sample display, the ability to identify the direction of letter E decreases at the optotype of the same line thickness. The change of MAR shows linear trends with respect to the optical power change that are the reciprocal of the distance from the participant to the crossing points located out of screen and on screen. 相似文献
43.
Microcapsule with poly(ethylene‐co‐vinylacetate) (EVA) core‐polyurethane (PU) shell structure was synthesized by interfacial polymerization in aqueous polyol dispersion with ethylene diamine as the chain extender of toluene diisocyanate in poly(vinyl alcohol) aqueous solution as the stabilizing agent. The effects of polyol constituent on the average particle size and distributions, morphologies, color strength, and friction fastness of core‐shell particles were investigated to design microcapsule. The friction fastness of printed fabrics with EVA core‐PU shell microcapsules became the increase to 4–5 grades. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 893–902, 2007 相似文献
44.
Moon Sam Shin Ki-Pung Yoo Chul Soo Lee Hwayong Kim 《Korean Journal of Chemical Engineering》2006,23(3):469-475
A multi-fluid nonrandom lattice fluid model with no temperature dependence of close packed volumes of a mer, segment numbers
and energy parameters of pure systems is presented. The multi-fluid nonrandom lattice fluid (MF-NLF) model with the local
composition concept was capable of describing properties for complex systems. However, the MF-NLF model has strong temperature
dependence of energy parameters and segment numbers of pure systems; thus empirical correlations as functions of temperature
were represented for reliable and convenient use in engineering practices. The MF-NLF model without temperature dependence
of pure parameters could not predict thermodynamic properties accurately. It was found that the present model with three parameters
describes quantitatively the vapor pressure and the saturated density for the pure fluid. 相似文献
45.
Polycaprolactone (PCL)/starch and PCL/starch/pine‐leaf composites, which can be possibly applied as biodegradable food packaging materials with natural pine flavor, were prepared and characterized in this study. The effect of incorporating a silane coupling agent at different content levels on the physical properties and morphology of the composites was studied. To investigate the melting behavior of the composites, a differential scanning calorimetry was employed. A universal testing machine was used to investigate the tensile properties of the composites and the water absorption properties of the composites were also investigated. Scanning electron microscope was used to investigate the morphology of the composites. The physical properties and morphology of the PCL/starch and PCL/starch/pine‐leaf composites were largely affected by the composition, especially the content of the silane coupling agent. The silane coupling agent led to a much better interfacial compatibility between the PCL matrix and the fillers and resulted in better physical properties of the composites. The PCL/starch/pine‐leaf composite with the silane coupling agent showed a morphology, indicating a good interfacial adhesion between the PCL matrix and the fillers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 928–934, 2007 相似文献
46.
Highly transparent ZnO thin films were deposited at different substrate temperatures by pulsed laser deposition in an oxygen atmosphere. The thin films were characterized by various techniques including X-ray diffraction, scanning electron microscopy, optical absorption, and photoluminescence. We demonstrated that oriented wurtzite ZnO thin films could be deposited at room temperature using a high purity zinc target. Variable temperature photoluminescence revealed new characteristics in the band edge emission. The underlying mechanism for the observed phenomena was also discussed. 相似文献
47.
Hyun Min Shim Joon Soo Lee Hong Yue Wang Seung Hak Choi Jeong Hoon Kim Hyung Taek Kim 《Korean Journal of Chemical Engineering》2007,24(3):537-541
The main purpose of the study was to develop a model using ASPEN and Excel simulation method to establish optimum CO2 separation process utilizing hollow fiber membrane modules to treat exhaust gas from LNG combustion. During the simulation,
optimum conditions of each CO2 separation scenario were determined while operating parameters of CO2 separation process were varied. The characteristics of hollow fibers membrane were assigned as 60 GPU of permeability and
25 of selectivity for the simulation. The simulation results illustrated that 4 stage connection of membrane module is required
in order to achieve over 99% of CO2 purity and 90% of recovery rate. The resulted optimum design and operation parameters throughout the simulation were also
correlated with the experimental data from the actual CO2 separation facility which has a capacity of 1,000 Nm3/day located in the Korea Research Institute of Chemical Technology. Throughout the simulation, the operating parameters of
minimum energy consumption were evaluated. Economic analysis of pilot scale of CO2 separation plant was done with the comparison of energy cost of CO2 recovery and equipment cost of the plant based on the simulation model.
This work was presented at the 6
th
Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006. 相似文献
48.
Continuous solution copolymerization of methyl methacrylate with ethyl methacrylate or n-butyl methacrylate was carried out
in a continuous stirred tank reactor. Solvent and initiator used were toluene and benzoyl peroxide, respectively. Reaction
volume was 1.2 litters, residence time 3 hours and polymerization temperature 80°C. The copolymerization conversions were
analyzed by UV spectrophotometry and confirmed by measuring the solid weights of copolymers obtained after evaporating solvent.
The copolymerization of methyl methacrylate and alkyl methacrylates followed the second order kinetics. The simulated conversions
and copolymerization rates were compared with the experimental results. The average time to reach dynamic steady-state was
three and half times of the residence time. 相似文献
49.
Functionally graded materials (FGMs) belong to a relatively new class of inhomogeneous composite materials, in which the composition
and/or microstructure undergo a gradual change along some directions. In this review article, the microstructures and composition
gradients in Al/SiC, Al/Shirasu (volcanic eruptions commonly found in south Kyushu in Japan), Al/Al3Ti, Al/Al3Ni, Al/Al2Cu FGMs have been investigated. The Al/SiC, Al/Shirasu and Al/Al3Ti FGMs are fabricated by the centrifugal solid particle method where the distribution particles of SiC, Shirasu and Al3Ti are solids in the melts. On the other hand, Al/Al3Ni and Al/Al2Cu FGMs are fabricated by the centrifugalin-situ method where Al/Al3Ni and Al/Al2Cu systems have lower liquidus temperatures than the processing temperatures. The feature of Al/(Al3Ti−Al3Ni) hydrid FGM, which is fabricated by a method combining both the centrifugal solid-particle andin-situ methods, is also shown. 相似文献
50.
A study has been made to investigate the superplastic deformation mechanisms of 7475 Al alloy in relation to the variation of grain size ranging between 5.5 μm and 13 μm. The strain-rate sensitivity (m) was increased with decreasing grain size in the superplastic deformation regime. Microstructural investigation after tension tests revealed that the dispersoid free zones were produced mostly at the grain boundaries normal to the tensile direction. A new model for describing the deformation behavior of the 7475 Al alloy has been proposed based on the assumption that the grain boundary sliding was accommodated by both diffusional flow and slip. This new model well predicts many aspects of experimental results. 相似文献