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51.
There is interest in developing solid oxide fuel cells (SOFC) operated directly with liquid fuels such as methanol. This mode of operation increases the complexity of the anodic processes, since thermal and catalytic decomposition reactions are relevant. In this study, the pyrolysis and catalytic decomposition of methanol are investigated experimentally for conditions typical of SOFC. The results are compared to the thermodynamic equilibrium values and also to the predictions of a kinetics model. The main species of the thermal decomposition of methanol are H2, CO, and HCHO; soot formation is relevant below 973 K. The presence of a catalyst allows the gas-phase composition to reach equilibrium. However, the catalysts tested – Ni/YSZ, Ni/CeO2, Cu/CeO2 and Cu–Co/CeO2 – deactivate by coking so that the gas-phase composition reverts to that of pyrolysis alone. The results presented reveal part of the complex dynamics occurring within the anode compartment during the direct utilization of methanol. 相似文献
52.
Barnes Steven J.; Hua Josephine M.; Pinel John P. J.; Takahashi Aki; Wig Gagan S. 《Canadian Metallurgical Quarterly》2005,119(6):1572
Rats received kindling stimulations to the perirhinal cortex (PRh), ventral hippocampus (VH), or dorsal hippocampus (DH) in 1 environment and an equivalent number of sham stimulations in a 2nd environment. The PRh-kindled rats displayed rapid kindling and a swift emergence of conditioned interictal defensiveness. In contrast, the VH- and DH-kindled rats displayed much slower kindling and slow or no conditioning, respectively. No effects of conditioning on the convulsions, comparable with those associated with amygdala kindling, were observed. These results establish the generality of some of the previously reported kindling-related conditioned effects, confirm the site specificity of some of these effects, and suggest that the convulsions, rather than the stimulations, function as the unconditioned stimuli for the conditioning of interictal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
New Paradigm for Sizing Riparian Buffers to Reduce Risks of Polluted Storm Water: Practical Synthesis 总被引:2,自引:0,他引:2
M. Todd Walter Josephine A. Archibald Brian Buchanan Helen Dahlke Zachary M. Easton Rebecca D. Marjerison Asha N. Sharma Stephen B. Shaw 《Canadian Metallurgical Quarterly》2009,135(2):200-209
Riparian buffers are commonly promoted to protect stream water quality. A common conceptual assumption is that buffers “intercept” and treat upland runoff. As a shift in paradigm, it is proposed instead that riparian buffers should be recognized as the parts of the landscape that most frequently generate storm runoff. Thus, water quality can be protected from contaminated storm runoff by disassociating riparian buffers from potentially polluting activities. This paper reviews and synthesizes some simple engineering approaches that can be used to delineate riparian buffers for rural watersheds based on risk of generating runoff. Although reference is made to specific future research that may improve the proposed methods for delineating riparian buffers, the approaches described here provide planners and engineers with a set of currently available scientifically defensible tools. It is recommended that planners and engineers use available rainfall and stream discharge data to parameterize the buffer-sizing equations and use variable-width buffers, based on a topographic index, to achieve a realistic representation of runoff generating areas. 相似文献
54.
It has been hypothesized that women may be less likely to obtain therapeutic benefit from nicotine replacement therapy (NRT). The present study tested this hypothesis, using two different types of NRT medications. A secondary analysis of two randomized clinical trials was performed: One compared active 21-mg nicotine patch with placebo among 193 men and 309 women, and the other compared active 2-mg or 4-mg nicotine lozenge with placebo among 788 men and 1,030 women. Using logistic regression analysis of 6-month continuous abstinence and survival analysis, we assessed the efficacy of patch and lozenge among women and tested for a gender x treatment interaction. Active NRT was more effective than placebo among women, for both patch and lozenge. In the lozenge trial, women were less successful than men. The gender x treatment interaction was not significant in either study, whether assessed by logistic regression or survival analysis. In the lozenge trial, gender moderated the effects of smoking rate and dependence (but not treatment) on outcome: These variables affected success rates only among women. Treatment with nicotine patch or lozenge is effective for women, and the analysis did not reveal significant gender differences in efficacy. Gender differences in outcome may be moderated by nicotine dependence. 相似文献
55.
Josephine Reid Richard Hull Tom Melamed Duncan Speakman 《Personal and Ubiquitous Computing》2003,7(3-4):197-202
This paper describes the design process and lessons learned from creating Schminky, a café-based digital experience. Schminky was developed as an experimental field trial to explore the role of pervasive computing. The game will be played by the general public for one week in the Watershed café in Bristol. The Schminky system and the experience design process is described and three key findings, creative tension, context and content are discussed. 相似文献
56.
Many naturally occurring sterols are accumulated and metabolized byTetrahymena pyriformis. In most cases, the sterols are desaturated to giveΔ5,7,22-derivatives. Compounds with an ethyl, but not with a methyl, substituent at C-24 are dealkylated. Exposure of the ciliates
to the appropriate sterol sharply curtails the synthesis of the native pentacyclic triterpenoid alcohols, tetrahymanol and
diplopterol. An analysis with modified sterols has revealed several additional features that are required for desaturation
at C-7,8 and C-22,23 and for inhibition of tetrahymanol biosynthesis. The presence of atrans-17(20)-double bond, which eliminates free rotation at C-20 and fixes C-22 to the right of the nucleus, does not interfere
with desaturation, while thecis- or left-handed isomer is not metabolized. Thecis-Δ17(20)-isomer is, however, an effective inhibitor of tetrahymanol biosynthesis, although less so that thetrans-counterpart. When a methyl or hydroxyl group at C-20 protrudes to the front of the molecule in the right-handed conformation,
metabolism is reduced or abolished. Shortening (by one C-atom) or lengthening of the sterol side chain has little effect on
the ability of the compounds to inhibit tetrahymanol biosynthesis or to support growth, as long as the overall length of the
side chain does not exceed seven carbons from C-20. The presence of a 7α-, 7β-, 20α-, 20β-, or a 25-hydroxy group in the cholesterol
molecule sharply inhibits desaturation and curtails the effectiveness of the compound as an inhibitor of tetrahymanol biosynthesis.
The 7- or 22-keto derivatives seem to act in a fashion similar to the hydroxy derivatives, but these compounds show greater
inhibition of growth. 20-Methylcholesterol, however, is a potent inhibitor of synthesis, which suggests that the polarity
of the substituent of C-20 is more important than bulk. Many sterols can effectively replace tetrahymanol in the membranes
of these ciliates. However, several of the compounds, which inhibit synthesis, appear to be physiologically inappropriate,
and poor growth results. An example of the latter class is 20-methylcholesterol. Finally, a class of sterols, represented
by 20α-hydroxycholesterol and 7-ketocholesterol, does not severly inhibit tetrahymanol synthesis but leads to growth inhibition
and surface abnormalities. These sterols apparently lead to a disordered membrane, even in the presence of tetrahymanol. 相似文献
57.
Whether one is prepared for them or not, personal challenges that affect professional roles are a fact of life. The author discusses the immediate and enduring consequences of the diagnosis of, treatment of, and recovery from a life-threatening illness as they relate to practicing psychology. In particular, the areas impacted, such as work responsibilities, training and supervision, and professional development, are addressed. In addition, clients' reactions and personal responses to those reactions are considered. The more enduring impact on the understanding of several common therapeutic concepts, including emotional avoidance, rational versus irrational beliefs, just worldview, and acceptance, is explored. Finally, practical implications and recommendations are made. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
E. Strain, K. E. Patterson, and M. S. Seidenberg (2002) reported an effect of imageability and a Regularity X Imageability interaction in a regression analysis of naming latencies to 120 words. One of their items (couth) was named correctly by just 5 of their 24 participants, and its reaction time was an outlier on their distribution. When that single item is removed, the significant predictors are age of acquisition (AoA), word frequency, regularity, and length. Analyses of the combined data from J. Monaghan and A. W. Ellis's (2002) Experiments 1-3 indicate that AoA predicts naming latencies for exception words but not consistent words. E. Strain et al.'s other points are considered in the light of these observations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
B Brimhall P Stenzel SL Dresler M Hermodson K Stangland J Joyce RT Jones 《Canadian Metallurgical Quarterly》1977,9(3):237-260
The amino acid compositions of the tryptic peptides of the following carnivore hemoglobin chains have been determined: gray fox (Urocyon cineroargenteus); raccoon (Procyon lotor); polar bear (Thalarctos maritimus); coati mundi (Nasua nasua) beta chain; coati mundi (Nasua narica) two beta chains; cat (Felis catus) alpha chain; and lion (Pantbera leo) beta chain. These provide a basis for future sequencing of these hemoglobins and construction of an evolutionary tree. The specific results are summarized in the following article (Stenzel and Brimhall, 1977). 相似文献
60.
Hilgard Ernest R.; Hilgard Josephine R.; Macdonald Hugh; Morgan Arlene H.; Johnson Lynn S. 《Canadian Metallurgical Quarterly》1978,87(6):655
Simulation of covert pain, as reported by the hidden observer method, proved very successful for 12 simulator Ss known to be unable to reduce overtly reported pain through hypnotic analgesia procedures, as compared with 12 highly hypnotizable Ss whose pain had been shown to be reduced by at least one third through hypnotic analgesia suggestions. Preliminary practice in dissociation (and in simulated dissociation) through amnesia for a word list and through attempted automatic writing also demonstrated successful simulation. However, in an honesty inquiry by a staff member not participating as a hypnotist-experimenter, no simulator claimed to have been amnesic, to have performed automatic writing, or to have reduced pain beyond the reduction that could be achieved through waking suggestion. The methods by which the successful simulation was achieved were explored in subsequent interviews. In contrast with the simulators, no highly hypnotizable S modified any earlier report on the basis of the honesty inquiry. Results confirm the importance of postexperimental honesty interrogation when the real–simulator design is used. Results also lend support to the reality of the covert experience of pain in the absence of its overt experience in hypnotic analgesia. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献