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61.
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Jerry Nwankwo  Amos Turk 《Carbon》1975,13(6):495-499
Electron spin resonance and thermal analysis have been used to investigate the catalytic oxidation of organic vapors adsorbed on activated carbon. Particular attention is given to determination of the temperature interval between oxidation of the adsorbate and burnoff of the carbon, and to the study of the oxidation states of the catalyst during repeated adsorption-oxidation cycles.  相似文献   
63.
48 males participated in an aggression task after receiving either alcoholic or placebo beverages and after being told that they had received either a high or a low dose of alcohol. All Ss in the alcohol group actually received the same dose. Measures of aggression were the intensity and duration of shock given to a bogus partner in a RT-pain perception task and a score on a posttask attitude questionnaire. Blood alcohol readings were taken 3 times during the session, and a locus of control scale was administered before and after drinking. For Ss in the alcohol conditions, blood alcohol levels averaged .079% before the task and .085% afterwards. Alcohol resulted in higher aggression scores only on the questionnaire measure, and an interaction between drug and attribution was found for the measure of shock duration. Attribution alone resulted in greater aggression on the measure of shock intensity. Ss in groups where the attribution was discrepant with the drug condition were the most aggressive on the measures of shock intensity and duration. These Ss became more external, reflecting a high correlation between their aggression and a stimulus tone. Results suggest that a person's increased aggressiveness when intoxicated results from an interaction between alcohol and an altered responsivity to provoking stimuli. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Minimizing entropy generation is a technique that helps improve the effectiveness of real processes by studying the associated irreversibility of system performance of nanofluid. This study examines the entropy generation analysis of electromagnetohydrodynamic radiative Casson flow induced by a stretching Riga plate in a non-Darcian porous medium under the influence of internal energy change, Arrhenius activation energy, chemical reaction, and melting heat transfer. The thermophysical features of the fluid are assumed constant in most of the literature. However, this current research bridges this gap by considering viscosity, conductivity, and diffusivity as temperature-dependent variables. Also, the exponential decaying Grinberg term is used as a resistive force in this investigation due to the electromagnetic properties of the Riga plate in the momentum conservation equation. Some suitable dimensionless variables are introduced to remodel the transport equations into unitless ones and then solved numerically by employing Galerkin Weighted Residual Method. Analyses reveal that the Casson parameter declines the fluid velocity, while the existence of the melting parameter has the opposite effect. Also, this article includes some future recommendations.  相似文献   
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An efficient third-generation asymmetric synthesis of tricyclic lactone (+)-1, designed to serve as the common intermediate for construction of the indole tremorgens, has been developed. The major challenge was stereocontrolled introduction of the vicinal quaternary methyl groups. Our initial approaches employed enolate chemistry to install the second methyl moiety; herein we exploit instead a hydroxyl-directed Simmons-Smith cyclopropanation followed by reductive opening of the three-membered ring. The new 15-step synthesis proceeds in 8.3% overall yield, nearly an eightfold increase over the second-generation route, and is amenable to large-scale production of (+)- 1.   相似文献   
69.
Rechargeable battery cells having a liquid electrolyte require a separator permeable to the electrolyte between the two electrodes. Because the electrodes change their volume during charge and discharge, the porous separators are flexible polymers with an electronic energy gap Eg large enough for the Fermi levels of the two electrodes to be within it. In this work, a porous film of self‐assembled SiO2 nanoparticles is developed as the separator for a Li‐ion battery with a liquid electrolyte. This coating does not require the plasticity of a polymer membrane and has the required large Eg. If adsorbed water is removed from the SiO2 surface, the nanoparticles bond to one another and to an oxide cathode to form a plastic self‐assembling porous layer into which the liquid electrolyte can penetrate. The Li‐ion batteries with a LiCoO2 cathode coated with SiO2 as a separator show similar performance to cells with a traditional polypropylene separator and improved cyclability with a reduced volume of liquid electrolyte owing to the electrolyte wetting properties of the SiO2 nanoparticles. The SiO2 nanoparticles are easy to prepare, cheap, and environmentally friendly.  相似文献   
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The ultrastructural findings of the bone marrow cells from 15 patients with acquired sideroblastic anemia are presented. The red cell precursors from all patients showed the presence of electron-dense material in the mitochondria, representing most probably iron deposits. A great number of these mitochondria were completely destroyed. The erythropoietic precursors from one of the patients showed markedly elongated mitochondria that measured up to 3 microm. In addition numerous cytoplasmic vacuoles were observed. The red cell precursors from 60% of the patients showed signs of dyserythropoiesis, such as incomplete nuclear division and nuclear distortion. The polymorphonuclears from 47% of the patients presented nuclear abnormalities expressed as nuclear bridges, appendices, and blebs. In addition, phagocytosis of red blood cells was observed. The results of the study underline the advantages of the transmission electron microscope examination in visualization of intricate alterations in hematopoietic cells that cannot be detected with a light microscope.  相似文献   
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