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991.
Jae-Wook Lee Kyung-June Hwang Wang-Geun Shim Kyung-Hee Park Hal-Bon Gu Kyu-Hyuk Kwun 《Korean Journal of Chemical Engineering》2007,24(5):847-850
Dye sensitized solar cells (DSSCs) have been receiving significant attention because they have many advantages compared to
conventional organic solar cells. It has been known that the photovoltaic characteristics of DSSC are highly dependent on
the adsorption properties of dyes on TiO2 films. To analyze the surface heterogeneity of TiO2 surfaces, single-phase anatase nanocrystallite titanium films were prepared by sol-gel method using the hydrolysis reaction
of titanium tetraisopropoxide under acidic condition and characterized by XRD, FE-SEM and BET analysis. The adsorption energy
distribution functions were calculated by the generalized nonlinear regularization method. It was found that the shape and
the intensity of the adsorption energy distribution curve determined were highly related with the physical properties (i.e.,
geometrical heterogeneity) and chemical characteristics (i.e., energetic heterogeneity) of nanocrystalline TiO2 for DSSC. 相似文献
992.
随着计算机处理图形图像的技术日益完善,CG制作越来越频繁地出现在生活中,其中的三维动画尤为常见。Maya是现在国际最为流行的顶级三维动画制作软件。通过Episode动画短片的制作,介绍运用Maya制作三维动画的步骤和过程。 相似文献
993.
994.
995.
996.
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
997.
998.
Jim D. Earls Jerry E. White Marvin L. Dettloff Marty J. Null 《Journal of Coatings Technology and Research》2004,1(3):243-245
Epoxidized 10-undecenoic acid triglyceride, an experimental seed oil derivative that has a terminal epoxy group on each of
the three acyl glyceride segments, has been found to have good reactivity with amine curatives and allows room temperature
cures to be obtained. Coatings based on epoxidized 10-undercenoic acid triglyceride have also shown excellent UV stability.
As an example, coatings samples placed in a QUVA chamber exhibit no loss in gloss after 3000 hr of a cycled exposure to high
intensity UV lamps and moisture at temperatures of 50–60°C. In comparison, coatings based on standard liquid epoxy resins
(LERs) and commercially available hydrogenated LERs lose gloss due to chalking/decomposition within 200–800 hr.
Presented at the 81 st Annual Meeting of the Federation of Societies for Coatings Technology, November 12–14, 2003, in Philadelphia,
PA. 相似文献
999.
1000.
The pulsed arc discharge to the surface of wastewater was applied to the degradation of a textile azo dye (Acid Red 27). A
high-voltage electrode (discharging electrode) was vertically placed above the surface of the wastewater while the wastewater
itself was grounded. The pulsed arc discharge occurred between the tip of the discharging electrode and the surface of the
wastewater, producing various oxidative species. Oxygen was used as the working gas instead of air to prevent nitrogen oxides
from forming. The effect of several parameters on the chromaticity and chemical oxygen demand (COD) removal was examined.
The results obtained showed that the chromaticity of the wastewater was completely removed by this process and the COD also
decreased significantly. It has been found that ozone formed in the gas phase mainly affects the removal of the dye. The contribution
of other effects such as ultraviolet light emission and OH radical formation during the arc discharge to the degradation of
the dye was found to be less than 15%. For the present reactor system, the optimum pH, pulse repetition rate and agitation
speed were found to be 3.0, 110 Hz and 300 rpm, respectively. 相似文献