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211.
The feasibility of a direct internal reforming (DIR) solid oxide fuel cell (SOFC) running on wet palm‐biodiesel fuel (BDF) was demonstrated. Simultaneous production of H2‐rich syngas and electricity from BDF could be achieved. A power density of 0.32 W cm?2 was obtained at 0.4 A cm?2 and 800 °C under steam to carbon ratio of 3.5. Subsequent durability testing revealed that a DIR‐SOFC running on wet palm‐BDF exhibited a stable voltage of around 0.8 V at 0.2 A cm?2 for more than 1 month with a degradation rate of approximately 15 % / 1000 h. The main cause of the degradation was an increase in the ohmic resistance. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
212.
Cokley Kevin O.; Tran Kimberly; Hall-Clark Brittany; Chapman Collette; Bessa Luana; Finley Angela; Martinez Michael 《Canadian Metallurgical Quarterly》2010,3(3):187
[Correction Notice: An erratum for this article was reported in Vol 4(3) of Journal of Diversity in Higher Education (see record 2011-16523-001). There are two errors in Table 2 under the RWA heading and the Cog-gender heading. The necessary changes are provided in the erratum.] [Correction Notice: An erratum for this article was reported in Journal of Diversity in Higher Education on August 1 2011 (see record 2011-16523-001). There are two errors in Table 2. Under the RWA heading, the SDO row should have indicated a positive correlation of .266**, not -.266**. Under the Cog-gender heading, the SDO row should have indicated a negative correlation of -.438**, not .438**.] Factors related to attitudes about racial diversity and gender equity were examined in an ethnically diverse sample of 432 college students (167 European Americans, 83 African Americans, 81 Asian Americans, and 82 Hispanic Americans). In addition to variables of self-interest (i.e., ethnicity, gender, and political views), social ideology (i.e., social dominance orientation, right-wing authoritarianism) and personality traits (openness to experience) were uniquely predictive of attitudes about racial diversity and gender equity. Hierarchical regressions revealed that social dominance orientation most strongly predicted racial attitudes, while right-wing authoritarianism most strongly predicted gender attitudes. Implications for diversity education efforts related to prejudice reduction are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
213.
T T Tran A W Burgess H Treutlein J Zeng 《Journal of molecular graphics & modelling》2001,20(3):245-256
When the oxygen atom in a peptide bond is replaced by a sulfur atom, the restriction in the available conformational space and the ability of thioamides to confer resistance to enzymatic degradation renders thioamides as potentially useful building blocks for drug design and protein engineering. The solvation free energy differences between conformers of the same dipeptide can be high. Yet, previous conformational studies, basing on the (phi, psi) conformational energy maps of thio-substituted dipeptides, neglected both explicit water interactions and free energy considerations. In this paper, the (phi, psi) conformational free energy maps are obtained by single umbrella sampling in an explicit water environment for both alanine dipeptide and the corresponding thioamide derivatives. The phi and psi angles for the minima in the relative energy maps calculated with dielectric of 80 are similar to the corresponding phi and psi angles in the relative free energy maps for both Ac-Ala-NHMe (Ac: acetyl; Ala: alanine) and Act-Alat-NHMe (Act: thio-acetyl; Alat: thio-alanine). However, some large differences between the relative energy and relative free energy of major minima indicate that the consideration of free energy is important in determination of the relative occupancy of particular minima. Free energy maps for both Ac-Ala-NHMe and Act-Alat-NHMe show that thio-substitution favors conformations where phi < 0 because of the deeper beta and alphaR minima. The changes in the position and relative stability of minima were explained in terms of the destabilization of the regions near phi = -120, 0 and 120, psi = 60, -60, 180, which correspond to the increased steric hindrance due to the bulkier sulfur atom. 相似文献
214.
Manipulations of the lactation cycle are achieved through nutritional regimens and generally result in a restriction of the physiological lactation cycle. Most models of lactation used in management programmes only describe the average time course of lactation for groups of cows on a given feeding regimen. This is inadequate for the variety of feeding systems in use on British farms. In the present paper several existing models of lactation have been critically evaluated. An integral equation approach has been developed to rationalize experimental observations and currently accepted biological concepts. 相似文献
215.
216.
An assessment of three institutional models for irrigation management in Vietnam is presented. The first model is a joint management by a state agency and farmer organization; the second is a shared management by a quasi-state and farmer organization; and the third is management solely by a farmer organization. The first model is a conventional management system, whereas the latter two models have recently been introduced in a limited number of projects as a result of the government policy on reform in the irrigation sector. Three study sites are identified to represent three management models. Apart from the institutional framework and selected management functions, water distribution and agricultural productivity are evaluated and compared. Results indicate the better performance of management models with increased involvement of farmers in the decision-making process. It is recommended that the hydraulic boundaries should be taken into consideration in reforming management systems for irrigation projects. 相似文献
217.
EH Herman J Zhang BB Hasinoff KT Tran DP Chadwick JR Clark VJ Ferrans 《Canadian Metallurgical Quarterly》1998,128(1):35-52
We have determined the time course, the spatial spread in brain tissue, and the intracellular distribution of biotin- and fluorescein-labeled phosphorothioate oligodeoxynucleotides (ODNs) following single injections into the rat striatum or the lateral ventricle. These time and space parameters were correlated with the ability of c-fos phosphorothioate antisense ODNs to suppress the induction of Fos protein by cocaine. A rapid and dose-dependent tissue penetration of labeled ODNs was observed following either intrastriatal or intraventricular injections of a constant sample volume. Inspection of tissue sections by confocal microscopy uncovered a distinct change in the intracellular disposition of labeled ODNs during the 24 h post-injection period. At 1, 6 and 12 h, the vast majority of the fluorescent signal was confined to the interstitial spaces throughout the zone penetrated by ODNs. Neuronal nuclei displayed faint labeling along the outer portion of the nucleus at 1 and 6 h post-injection. At these time-points, ODNs were not detected in the cytoplasm. By 16 h, ODNs were barely detectable in the extracellular space and absent from neuronal nuclei. Instead, ODNs were seen in large cytoplasmic granules of neurons throughout the tissue zone penetrated by the ODNs. Experiments with intrastriatal injections of antisense ODNs to c-fos mRNA revealed Fos suppression between 3 and 12 h, but not at 16 and 24 h. This combined analysis has revealed that (1) restricted tissue penetration by ODNs limits their antisense effects on protein expression, and (2) depletion of extracellular ODNs and sequestration of c-fos antisense ODNs into large intracellular granules coincides with the loss of their biological activity. 相似文献
218.
T. K. Tran A. Parikh S. D. Pearson B. K. Wagner R. G. Benz R. N. Bicknell-Tassius C. J. Summers T. Kelz J. W. Tomm W. Hoerstel P. Schäfer U. Muller 《Journal of Electronic Materials》1996,25(8):1203-1208
We present a study of the electro-optical properties ofHg
1- xCdxTe epitaxial layers and Hg1-x CdxTe/CdTe (0.28 < x < 0.30) superlattice structures by x-ray diffraction, lateral transport and photo- and magneto-luminescence
measurements. Systematic studies of the excitation intensity and magnetic field dependence of the photoluminescence revealed
direct evidence of an excitonic contribution to the observed luminescence in Hg1- xCdxTe epitaxial layers. Similar investigations of the superlattice structures indicated that excitonic corrections were required
to adequately fit the luminescence data. Optical gains of 80 cm−1 were obtained for an excitation intensity of 100 kW/cm2 indicating suitable electro-optical properties for making efficient mid-infrared laser diodes. 相似文献
219.
220.