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991.
Tao Yang Jian Liu Harry Finklea Shiwoo Lee Willam K. Epting Rubayyat Mahbub Tim Hsu Paul A. Salvador Harry W. Abernathy Gregory A. Hackett 《International Journal of Hydrogen Energy》2018,43(32):15445-15456
In the present study, an efficient approach for the prediction of Warburg-type element is proposed via the analysis of the anode-supported solid oxide fuel cell (SOFC) performance under various working conditions. The details of the performance, polarization curves, impedance behavior, and species distribution profiles within the electrode are investigated via the combination of equivalent circuit model (ECM) analysis and multiphysics numerical simulations. The multiphysics simulation is developed and calibrated with experimental results of SOFC button cells under various working currents. With the complete datasets generated from the calibrated simulations, the trends of the element parameters involved in equivalent circuit model are analyzed. Generalized empirical functions are proposed as well as the procedures of prediction of performance under different conditions. The verification cases show good agreement between the predicted results from proposed model and the reference results. This proposed approach can be utilized to quickly predict the properties for desired performance in the manufacturing processes, and it also has the potential of reducing the computational cost in the simulation of large SOFCs. 相似文献
992.
993.
Polarographic residue methods have been developed for determining robenidine (Robenz), 1,3-bis[p-chlorobenzylidene)amino]-guanidine monohydrochloride, in chicken tissues, eggs, litter, soil, and plants. The compound is extracted from chicken fat, skin, muscle, liver, and eggs with ethyl acetate; from blood with acetone; from plant tissue, litter, and kidney with acidic acetone; and from soil with basic methanol. After extraction by high-speed blending or overnight shaking, the extract is cleaned up by evaporation, solvent partition and/or elution from CG-50 ion exchange resin. Robenidine is quantitated by differential cathode ray polarography, using acidic aqueous methanol or acetic acid (1+1) supporting electrolyte. Recoveries ranged from 64 to 125% with an average overall recovery of 90%. The validated sensitivity is 0.1 ppm for chicken tissues, soil, and plants, 0.01 ppm for eggs, and 1 ppm for litter. 相似文献
994.
995.
Two cases are described in which, during investigation of rhythm disturbances, it was shown that, by delivering atrial stimuli of increasing prematurity, a point was reached where the artificial stimulus failed to induce an atrial response. However, with even more premature stimulations, atrial responses were again observed. These observations are best explained by a gap phenomenon in which very early stimuli delivered during the effective refractory period of the atria were delayed long enough in the exit area around the pacing electrode to allow atrial recovery. 相似文献
996.
The calculation of equilibrium binding constants for a specific receptor-hormone interaction requires the exact determination of the unbound ligand concentration and the specifically bound concentration at equilibrium. These determinations usually require corrections for the contribution of non-specific binding. We introduce several parameters allowing equilibrium concentrations to be calculated from experimental concentration values; these parameters can be measured for the particular receptor assay procedure used. These parameters are used in a microassay of estradiol-receptor complex by selective retention on DE-81 cellulose paper. 相似文献
997.
The effect of morphine microinjection (5 microgram/0.5 microliter) and focal electrical stimulation on the animal's response to radiant heat and noxious pinch was studied concurrently at 117 brain loci extending from the medial thalamus caudally to the periaqueductal gray area (PAG). Three populations of brain sites were discernible based on their responsiveness to focal electrical stimulation and morphine microinjection in the production of antinociception: (a) sites which support stimulation-produced analgesia (SPA, n = 24), (b) sites which were sensitive to the direct application of morphine (n = 8), (c) sites responsive to both manipulations (n = 8). With a few exceptions, all morphine sensitive sites were located within the anatomical boundaries of the PAG while sites supporting SPA were located not only within the PAG but also in the brain regions peripheral to this structure. Sites responsive to both manipulations were generally distributed throughout thf lateral aspect of the posteroventral PAG. Stimulation strength-effect curves for sites subserving SPA were also obtained. No differences were discovered between curves obtained from morphine-sensitive and -insensitive brain loci. 相似文献
998.
The neurological manifestations of achondroplasia include megalencephaly, hydrocephalus, and progressive myelopathy or radiculopathy secondary to spinal stenosis. Subarachnoid and intracerebral hemorrhage have not been previously reported in association with achondroplastic dwarfism. This report describes two patients with achondroplasia who have died secondary to intracranial hemorrhage. At autopsy, the source of hemorrhage was found to be an arteriovenous malformation of the choroid plexus in one case and a ruptured aneurysm of the left middle cerebral artery in the other. 相似文献
999.
The dependence on skin temperature of tactile sensitivity to punctiform (hair) stimulation of the finger tip came under study in five subjects. Their data show that punctate sensitivity is relatively stable over a wide range of thermal environments. On the average, some elevation of touch threshold occurred at a skin temperature of 20 degrees C (i.e., about 10 degree below normal), but severe loss of sensitivity first occurred at 10 degrees C. A small but possibly insignificant loss appeared at skin temperatures of 40 and 43 degrees C. The relatively stable behavior of the punctate threshold between about 20 and 40 degrees C contrasts with that of the vibrotactile threshold, which, at least for high frequencies, depends strongly on the skin temperature. 相似文献
1000.
The content (positive or negative) of interviewer self-disclosure regarding their own procrastination and study behavior as undergraduates was manipulated with all additional parameters of self-disclosure controlled. 16 male and 16 female college students discussed their tendency to procrastinate with either male or female interviewers who positively or negatively self-disclosed. Results indicate that (a) after the interview, Ss in the positive disclosure condition expected to study significantly more hours and did study significantly more hours than Ss in the negative disclosure condition; (b) Ss in the positive disclosure condition perceived that they procrastinated significantly more after the interview than before, while the opposite was true for Ss in the negative disclosure condition; and (c) negatively disclosing interviewers were perceived as significantly higher on unconditionality of regard and credibility than positively disclosing interviewers. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献