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991.
Emir E. Escalona Pedro R. Pereira-Almao Jimmy Castillo Jeannette Hung Carmelo Bolívar Carlos E. Scott 《Catalysis Letters》2006,112(3-4):227-230
NiMo and FeMo nanometric particles were prepared by thermal decomposition of water in oil emulsions, where the aqueous phase
was a solution of iron or nickel heteropolymolybdates. Decomposition experiments were carried out at 573 K and 70 Bar of hydrogen,
with carbon disulfide added to the emulsions. Solids were characterized by X ray diffraction, confocal microscopy and BET
surface area. Thiophene hydrodesulfurization was performed in a continuous flow microreactor at 553 K and 1.0 Bar. Particles
with diameters between 370 and 560 nm were obtained, and thiophene HDS was in the order NiMoS > MoS ≈ FeMoS > NiS > FeS. The
feasibility of using thermal decomposition of emulsions to obtain nanometric bimetallic sulfides particles was shown. 相似文献
992.
X-ray fluorescence of the chlorine atom is a suitable method for identifying vinyl in a mixed plastics stream in municipal solid waste. The chlorine X-ray is weak and does not penetrate paper labels. There is also a rapid decrease in measured chlorine X-ray intensity as the sample is moved away from the X-ray source and detector which could be a potential problem for bottles of uneven shape. 相似文献
993.
The present authors (see record 1985-08584-001) showed that the excitatory properties of fear facial expressions previously described by them (see PA, Vols 65:7371 and 68:2978) did not depend on associative mechanisms. Even in the absence of reinforcement, fear faces intensified the emotional reaction to a previously conditioned stimulus and disrupted extinction of an acquired fear response. In conjunction with the findings on acquisition, the failure to obtain extinction suggests that fear faces have some of the functional properties of "prepared" (fear-relevant) stimuli. The present study, with 60 undergraduates, compared the magnitude of conditioned fear responses to happy and fear faces when a potent danger signal, the shock electrodes, are attached or unattached. If fear faces are functionally analogous to prepared stimuli, then, even in the absence of veridical support for an expectation of shock, they should retain excitatory strength, whereas happy faces should not. Results are consistent with this view of fear expressions. In the absence of reinforcement, and with shock electrodes removed, conditioned fear responses and basal levels of arousal were greater for the fear-face condition than for the happy-face condition. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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997.
Urteaga M. Scott D. Krishnan S. Yun Wei Dahlstrom M. Griffith Z. Parthasarathy N. Rodwell M.J.W. 《Solid-State Circuits, IEEE Journal of》2003,38(9):1451-1456
We report tuned amplifiers designed for the 140-220-GHz frequency band. The amplifiers were designed in a transferred-substrate InP-based heterojunction bipolar transistor technology that enables efficient scaling of the parasitic collector-base junction capacitance. A single-stage amplifier exhibited 6.3-dB small-signal gain at 175 GHz. Three-stage amplifiers were subsequently fabricated with one design demonstrating 12.0-dB gain at 170 GHz and a second design exhibiting 8.5-dB gain at 195 GHz. 相似文献
998.
Siri Simona; Kensinger Elizabeth A.; Cappa Stefano F.; Hood Kristin L.; Corkin Suzanne 《Canadian Metallurgical Quarterly》2003,17(4):630
In this article the authors describe a patient (J.P.) whose category-specific naming deficit eluded the classical dichotomies between living versus nonliving items or visual versus functional attributes. At age 22, he had herpes simplex encephalitis followed by a left temporal lobectomy. J.P. was tested on measures of visual perception, category naming, fluency, and name-picture matching. He showed a severe impairment naming and identifying fruits, vegetables, and musical instruments. His performance with animals and birds was spared inconsistently, meaning that even the preserved categories were, at some point, affected. J.P.'s unusual deficit supports the hypothesis that semantic knowledge is organized in the brain on the basis of object properties, which can cut across the living-nonliving categorical distinction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Zaslow Martha J.; Weinfield Nancy S.; Gallagher Megan; Hair Elizabeth C.; Ogawa John R.; Egeland Byron; Tabors Patton O.; De Temple Jeanne M. 《Canadian Metallurgical Quarterly》2006,42(1):27
This study examined predictions from preschool parenting measures to middle childhood cognitive and socioemotional child outcomes to explore whether parenting assessment methodologies that require more time, training, and expense yield better predictions of child outcomes than less intensive methodologies. Mother-child dyads (N=278) in low-income African American families were assessed when the child was in preschool, using maternal report, the Home Observation for Measurement of the Environment-Short Form (P. Baker & F. Mott, 1989; R. Bradley & B. Caldwell, 1984), and structured observational measures of parenting. Child outcomes reported by children, mothers, teachers, and direct assessment were collected 4 years later. All parenting methodologies showed some predictive value; however, observational parenting measures showed the strongest and most consistent predictions of child outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Comments on the original article "The impact of chief executive officer personality on top management team dynamics: One mechanism by which leadership affects organizational performance", by R. S. Peterson et al. (see record 2003-08045-002). This comment illustrates how small sample sizes, when combined with many statistical tests, can generate unstable parameter estimates and invalid inferences. Although statistical power for 1 test in a small-sample context is too low, the experimentwise power is often high when many tests are conducted, thus leading to Type I errors that will not replicate when retested. This comment's results show how radically the specific conclusions and inferences in R. S. Peterson, D. B. Smith, P. V. Martorana, and P. D. Owens's (2003) study changed with the inclusion or exclusion of 1 data point. When a more appropriate experimentwise statistical test was applied, the instability in the inferences was eliminated, but all the inferences become nonsignificant, thus changing the positive conclusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献