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991.
992.
High-entropy alloys are formed by synthesizing five or more principal elements in equimolar or near equimolar concentrations. Microstructure of the CoCrCuFeNiAl0.5Bx (x = 0, 0.2, 0.6, 1) high-entropy alloys under investigation is composed of a mixture of disordered bcc and fcc phases and borides. These alloys were tested gravimetrically for their corrosion resistance in simulated syngas containing 0, 0.01, 0.1, and 1 % H2S at 500 °C. The exposed coupons were characterized using XRD and SEM. No significant corrosion was detected at 500 °C in syngas containing 0 and 0.01 % H2S while significant corrosion was observed in syngas containing 0.1 and 1 % H2S. Cu1.96S was the primary sulfide in the external corrosion scale on the low-boron high-entropy alloys, whereas FeCo4Ni4S8 on the high-boron high-entropy alloys. Multi-phase Cu-rich regions in the low-B high-entropy alloys were vulnerable to corrosive attack. 相似文献
993.
994.
Schmidt Norman B.; Storey Julie; Greenberg Benjamin D.; Santiago Helen T.; Li Qian; Murphy Dennis L. 《Canadian Metallurgical Quarterly》2000,109(2):308
The present study evaluated the singular and interactive effects of a functional polymorphism (variation) in the serotonin transporter (5-HTT) gene and a psychological trait (anxiety sensitivity [AS], i.e., fear of arousal symptoms) in predicting subjective and physiological responses to a 35% carbon dioxide (CO?) challenge in a community sample (N?=?72). Genotypes were divided into 2 groups in accord with prior research. Findings were partially supportive of the hypothesized risk model. These indicated that the Group L genotype (homozygous for the 1 allele), compared with the Group S genotype (homozygous for the s allele plus heterozygous individuals), predicted greater fearful response to the biological challenge. There was also an AS?×?Genotype interaction predicting heart rate variability (HRV) in response to the CO?, suggesting that high AS plus Group L status predicts decreased HRV. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
996.
Benjamin J. Stewart Ali Navid Kristen S. Kulp Jennifer L. S. Knaack Graham Bench 《Yeast (Chichester, England)》2013,30(2):81-91
Methylglyoxal, a reactive, toxic dicarbonyl, is generated by the spontaneous degradation of glycolytic intermediates. Methylglyoxal can form covalent adducts with cellular macromolecules, potentially disrupting cellular function. We performed experiments using the model organism Saccharomyces cerevisiae, grown in media containing low, moderate and high glucose concentrations, to determine the relationship between glucose consumption and methylglyoxal metabolism. Normal growth experiments and glutathione depletion experiments showed that metabolism of methylglyoxal by log‐phase yeast cultured aerobically occurred primarily through the glyoxalase pathway. Growth in high‐glucose media resulted in increased generation of the methylglyoxal metabolite d ‐lactate and overall lower efficiency of glucose utilization as measured by growth rates. Cells grown in high‐glucose media maintained higher glucose uptake flux than cells grown in moderate‐glucose or low‐glucose media. Computational modelling showed that increased glucose consumption may impair catabolism of triose phosphates as a result of an altered NAD+:NADH ratio. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
997.
998.
Recently, Vul and Pashler (2008) demonstrated that the average of 2 responses from a single subject to general knowledge questions was more accurate than either single estimate. Importantly, this reveals that each guess contributes unique evidence relevant to the decision, contrary to views that eschew probabilistic representations of the evidence-gathering and decision-making processes. We tested an implication of that view by evaluating this effect separately in individuals with a range of memory spans. If memory span is the buffer in which retrieved information is assembled into an evaluation, then multiple estimates in individuals with lower memory spans should exhibit greater independence from one another than in individuals with higher spans. Our results supported this theory by showing that averaging 2 guesses from lower span individuals is more beneficial than averaging 2 guesses from higher span individuals. These results demonstrate a rare circumstance in which lower memory span confers a relative advantage on a cognitive task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Winegard Benjamin; Bailey Drew H.; Oxford Jonathan; Geary David C. 《Canadian Metallurgical Quarterly》2010,65(9):928
Comments on Evolutionary psychology: Controversies, questions, prospects, and limitations (see record 2010-02208-001) by Confer et al. We applaud Confer et al.’s (February–March 2010) clarifications of the many misconceptions surrounding the use of evolutionary analyses in psychology. As they noted, such misunderstandings are common and result in a curious tendency of some of our colleagues to criticize evolutionary psychology without a firm understanding of evolution itself. Confer et al. also did an admirable job acknowledging current unresolved issues among evolutionary psychologists (e.g., the relative importance of group selection on humans). The above said, we disagree with their view that a current limitation of evolutionary psychology is its inability to explain phenomena “that appear to reduce an individual’s reproductive success, and cannot be explained by mismatches with, or hijacking of, our psychological mechanisms by modern-day novel inputs” (Confer et al., 2010, p. 122). Mismatches between modern environments and environments of evolutionary adaptedness are only one set of explanations for seemingly maladaptive traits (Nesse, 2005). Another set involves evolutionary trade-offs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Benjamin Ibarra-Sevilla 《Nexus Network Journal》2013,15(1):107-125
Benjamin Ibarra-Sevilla examines the role of the sphere in the Open Chapel built in San Pedro y San Pablo Teposcolula during sixteenth century. This unique Mexican building contains a complex ribbed vault designed on a hexagonal plan forming a semi-spherical dome. The investigation examines the use of the sphere in this structure in light of the design precepts practiced during the Renaissance in Europe. Furthermore, the study finds the connections of these precepts with a mathematical solution to the sphere based on convex shapes theories. By revealing the intricacies of the underlying geometry applied to design this building, this text aims to demonstrate the scholastic and architectural relevance of this refined Mexican piece of architecture. 相似文献