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781.
Dong Ju Moon Jong Woo Ryu Sang Deuk Lee Byoung Sung Ahn 《Korean Journal of Chemical Engineering》2002,19(6):921-927
As a part of the development of a gasoline processor for integration with a proton-exchanged membrane (PEM) fuel cell, we
carried out the POX reforming reaction ofiso-octane, toluene and gasoline over a commercial methane reforming catalyst, and investigated the reaction conditions required
to prevent the formation of carbon and the effect of fuel constituents and sulfur impurities in gasoline. The H2 and CO compositions increased with increasing reaction temperature, while those of CO2 and CH4 decreased. It is desirable to maintain an O/C molar ratio of more than 0.6 and an H2O/C molar ratio of 1.5 to 2.0 for vehicle applications. It has been found that carbon formation in the POX reforming ofiso-octane occurs below 620 °C, whereas in the case of toluene it occurs below 640 °C. POX reforming of gasoline constituents
led to the conclusion that hydrogen production is directly related to the constituents of fuels and the operating conditions.
It was also found that the coke formation on the surface of catalysts is promoted by sulfur impurities in fuels. For the integration
of a fuel processor with PEM fuel cell, studies are needed on the development of new high-performance transition metal-based
catalysts with sulfur and coke-resistance and the desulfurization of fuels before applying the POX reformer based on gasoline
feed. 相似文献
782.
de Jong Peter J.; Merckelbach Harald; Arntz Arnoud; Nijmam Henk 《Canadian Metallurgical Quarterly》1992,101(4):724
20 treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by the behavioral treatment. In addition, untreated Ss were more confident about their contingency estimates than were treated Ss. The present results fit with earlier studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
783.
Quaternary Pt-based electrocatalyst for methanol oxidation by combinatorial electrochemistry 总被引:8,自引:0,他引:8
The demonstration to apply the combinatorial method using a repeated cyclic voltammetry is reported to find the anodic material for DMFC that shows a higher electrocatalytic activity and that can replace a portion of precious metals with cheap ones. The activity of newly found electrocatalyst whose composition was determined through high-throughput screening was compared with that of commercially available Johnson–Matthey Pt(50)Ru(50). It was found Pt(77)Ru(17)Mo(4)W(2) was more active and stable than Pt(50)Ru(50) in methanol electro-oxidation. The repeated cyclic voltammetry makes the combinatorial method expand into a screening tool to find the electrocatalyst that not only showing an initial excellent performance but also being active in the long-run reaction. 相似文献
784.
Yong Kyu Lee Tae-Hun Kim Sang Hoon Lee Jong Duk Lee Byung-Gook Park 《Nanotechnology, IEEE Transactions on》2003,2(4):246-252
We have proposed a new twin-bit silicon-oxide-nitride-oxide-silicon memory (TSM)-inverted sidewall patterning (ISP) cell which has twin oxide-nitride-oxides (ONOs) physically separated by the ISP method under one control gate. This TSM-ISP can control the trapped charge distribution and make diffusion barrier of charges, so that program/erase (P/E) endurance and retention can be increased. The trapping nitride is narrow enough to reduce hot-hole erase times. To estimate the new device characteristics, we have devised a special simulation method of silicon-oxide-nitride-oxide-silicon (SONOS) by implementing a simple idea in the conventional device simulator, "MEDICI." By placing the floating nodes in nitride with adjusted density, which is supposed to play the role of charge traps in nitride, we can estimate not only the conventional SONOS characteristics, but also the new SONOS characteristics, such as TSM-ISP. 相似文献
785.
Yeun‐Tae Kim Jong‐Ho Hong Sin‐Doo Lee 《Journal of the Society for Information Display》2006,14(12):1091-1095
Abstract— A highly bendable liquid‐crystal display was fabricated by using a multi‐functional elastomer substrate of self‐aligning LC molecules without any surface treatment. One of the two substrates is a plastic substrate while the other is a multi‐functional elastomer substrate produced by a replica‐molding technique. The multi‐functional elastomer substrate has pixel‐encapsulating walls that serve as spacers and provide mechanical stability and reproducibility against bending deformations. The highly bendable LCD demonstrates great flexibility, durability, and excellent electro‐optic performances in a highly bent state. 相似文献
786.
M Chen P SanMiguel AC de Oliveira SS Woo H Zhang RA Wing JL Bennetzen 《Canadian Metallurgical Quarterly》1997,94(7):3431-3435
Large regions of genomic colinearity have been demonstrated among grass species by recombinational mapping, but the degree of chromosomal conservation at the sub-centimorgan level has not been extensively investigated. We cloned the rice and sorghum genes homologous to the sh2 locus of maize on bacterial artificial chromosomes (BACs), and observed that a homologue of the maize a1 gene was also present on each of these BACs. In sorghum, we found a direct duplication of a1 homologues separated by about 10 kb. In maize, sh2 and a1 are approximately 140 kb apart and transcribed in the same direction, with sh2 upstream of a1. In rice and sorghum, this arrangement is fully conserved. However, the sh2 and a1 homologues are separated by about 19 kb in both rice and sorghum. We found low-copy-number and repetitive DNAs between the sh2 and a1 homologues of sorghum and rice. The sh2 and a1 homologues cross-hybridized, but the repetitive DNA and most low-copy-number sequences between these genes did not. These results indicate that maize, sorghum, and rice have conserved gene order and composition in the sh2-a1 region, but have acquired extensive qualitative and quantitative differences in the sequences between these genes. 相似文献
787.
Hartsuiker Robert J.; Pickering Martin J.; De Jong Nivja H. 《Canadian Metallurgical Quarterly》2005,31(5):921
When speakers repair speech errors, they plan the repair in the context of an abandoned word (the error) that is usually similar in meaning or form. Two picture-naming experiments tested whether the error's lexical representations influence repair planning. Context pictures were sometimes replaced with target pictures; the picture names were related in meaning or form or were unrelated. The authors measured target picture-naming latencies separately for trials in which the context name was interrupted or completed. Interrupted trials showed semantic interference and phonological facilitation, whereas completed trials showed semantic facilitation and phonological interference. Thus, errors influence repair production. The authors explain the polarity of these effects in terms of the literature on context effects in word production. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
788.
Several approaches to finding the connected components of a graph on a hypercube multicomputer are proposed and analyzed. The results of experiments conducted on an NCUBE hypercube are also presented. The experimental results support the analysis.This research was supported in part by the National Science Foundation under grants DCR84-20935 and MIP 86-17374. 相似文献
789.
Joon Ho Oum Uk Hyun Lee Yong Hoon Kang Jong Ryul Yang Songcheol Hong 《Electron Device Letters, IEEE》2005,26(8):527-529
A quantum-well infrared phototransistor with a pseudomorphic high-electron mobility transistor (pHEMT) structure is presented. The proposed phototransistor uses four periods of a GaAs/Al/sub 0.3/Ga/sub 0.7/As (50 /spl Aring//120 /spl Aring/) quantum-well absorption region, as well as an In/sub 0.15/Ga/sub 0.85/As quantum well conducting channel under the absorption layer. The phototransistor shows a large responsivity of 140 A/W around 6 /spl mu/m at 23 K (for a cutoff wavelength of 7.5 /spl mu/m). The relation between the photoconductive gain and the transconductance of the pHEMT structure is also investigated. 相似文献
790.
Geun Woo Kim Kang Yong Lee 《Components and Packaging Technologies, IEEE Transactions on》2006,29(1):47-53
To prevent crack propagation in a plastic small outline J-lead package with a dimpled diepad under an IR soldering process, parametric study and optimization with respect to material properties are done. The main design variables among all material properties are determined from the parametric study. Their optimized values are determined by applying a constraint optimization technique to the IC package. 相似文献