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111.
112.
Xingbo Liu Ever Barbero Jing Xu Matthew Burris Keh-Minn Chang Vinod Sikka 《Metallurgical and Materials Transactions A》2005,36(8):2049-2058
Corrosion tests of 316L and two intermetallic compounds Fe3Al and FeCrSi in industrial Galvanizing (Zn-0.18Al), GALFAN (Zn-5Al), GALVALUME (Zn-55Al), and Aluminizing (Al-8Si) baths
and lab-scale static baths were conducted. In on-line tests in industrial hot-dip baths, 316L steel shows better corrosion
resistance than Fe3Al in Galvanizing, GALFAN, and GALVALUME baths. The corrosion resistance of 316L and Fe3Al is similar in Aluminizing bath. In static tests, FeCrSi shows the best corrosion resistance in pure Zn, Zn-55Al, and Al-8Si
baths. The corrosion resistance of 316L is better than that of Fe3Al. In Zn-5Al bath, 316L shows no thickness loss after the test. For the same bath composition, the corrosion rates of the
alloys in industrial baths are higher than those in static baths. Bath temperature and chemical composition play important
roles in corrosion and intermetallic layer formation. Increasing bath temperature accelerates the corrosion process and changes
the nature of intermetallic layers. A small amount of aluminum reduces the corrosion process by reducing the activity of Zn
and forming inhibition layer. However, after aluminum content reaches the critical point, the dominant corrosion process changes
from Zn-Fe reaction to Al-Fe reaction, and, consequently, the corrosion process accelerates by increasing aluminum content
in the bath. 相似文献
113.
Trace fear conditioning is a learning task that requires the association of an auditory conditioned stimulus (CS) and a shock unconditioned stimulus (US) that are separated by a 20-s trace interval. Single neuron activity was recorded from the prelimbic and infralimbic areas of the medial prefrontal cortex in rats during trace fear conditioning or nonassociative unpaired training. Prelimbic neurons showed learning-related increases in activity to the CS and US, whereas infralimbic neurons showed learning-related decreases in activity to these stimuli. A subset of prelimbic neurons exhibited sustained increases in activity during the trace interval. These sustained prelimbic responses may provide a bridging code that allows for overlapping representations of CS and US information within the trace fear conditioning circuit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
Holahan Matthew R.; Taverna Franco A.; Emrich Stephen M.; Louis Meira; Muller Robert U.; Roder John C.; McDonald Robert J. 《Canadian Metallurgical Quarterly》2005,119(6):1563
Male Long-Evans rats were injected with 32 ng/μl of the N-methyl-D-aspartate (NMDA) receptor antagonist 3-(2-carboxypiperazin-4-yl) propyl-1-phosphonic acid (CPP) or vehicle and trained to locate a hidden platform in a different location (reversal training) than used on the initial 4 days of training. Rats treated with vehicle or CPP into the dorsal hippocampus, basolateral amygdala, or mediodorsal striatum had similar latencies to locate the platform on the reversal day. Rats infused with CPP into the dorsal hippocampus or mediodorsal striatum failed to search preferentially in the novel location during a 24-hr, drug-free retention test, whereas all other groups searched preferentially in this location. Therefore, blocking dorsal hippocampal or mediodorsal striatal NMDA receptors selectively blocked long-term spatial retention without producing short-term performance deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
Review of book Studies of How the Mind Publicly Enfolds into Being edited by William E. Smythe and Angelina Baydala. This volume contains the fruits of a symposium of the Western Canadian Theoretical Psychologists devoted to the topic contained in the title, though the original idea was expressed by considering "psyche and polis" (p. viii), the two Greek terms from which our conceptions of self and public largely derive. Most of the reflection does not return all the way to ancient Greece, but the essays draw deeply on historical sources, retracing the influences of contemporary thought and reminding the audience of some roads not taken. The issue and definition of self are the predominant theme. Judging from the references, the sources of inspiration for many of these essays is predominantly philosophical, with liberal borrowings from sociology, cultural studies, and political theory. Despite the complexity and range of theoretical issues discussed, the contributions are uniformly clear and engaging, a credit to authors and editors alike. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
116.
Roser Matthew E.; Fugelsang Jonathan A.; Dunbar Kevin N.; Corballis Paul M.; Gazzaniga Michael S. 《Canadian Metallurgical Quarterly》2005,19(5):591
An understanding of relations between causes and effects is essential for making sense of the dynamic physical world. It has been argued that this understanding of causality depends on both perceptual and inferential components. To investigate whether causal perception and causal inference rely on common or on distinct processes, the authors tested 2 callosotomy (split-brain) patients and a group of neurologically intact participants. The authors show that the direct perception of causality and the ability to infer causality depend on different hemispheres of the divided brain. This finding implies that understanding causality is not a unitary process and that causal perception and causal inference can proceed independently. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
In 3 experiments the authors examined changes in successive exemplar generation percentages within categories defined semantically (e.g., fruit-P, fruit-A, fruit-M) and by 1st letter (e.g., insect-C, sport-C, car-C), with a mixed control condition (e.g., fruit-P, insect-C, disease-M). Retrieval success declined across 12 successive items in both semantic and letter categories, with no change for the mixed condition. This retrieval inhibition is unrelated to taxonomic frequency of exemplars within either letter or semantic categorical structures. Furthermore, semantic retrieval inhibition appears to be long lasting, suggested by the decline in retrieval percentage across successive 12-item blocks in both the mixed and letter conditions. The authors suggest that different mechanisms underlie the inhibition found in the semantic (suppression) and letter (interference) conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Matthew T. Tilbrook 《Engineering Fracture Mechanics》2005,72(16):2444-2467
Cracks in stepped and continuously graded material specimens under flexural loading were investigated via finite element analysis. Calculation of mechanical energy release rates and propagation angles with crack-opening displacement correlation and the local symmetry (KII = 0) criterion, respectively, provided results most efficiently and accurately, as compared with compliance and J-integral approaches and other deflection criteria. A routine was developed for automatic crack extension and remeshing, enabling simulation of incremental crack propagation. Effects of gradient profile and crack geometry on crack-tip stresses and crack propagation path are examined, and implications of these for optimal design of graded components against failure by fast fracture are discussed. 相似文献
119.
Abstract— Two measurement methods to characterize uniformity and the absolute cell gap of LCoS images will be reviewed. These are simple to use in a production environment and have allowed major improvements in manufacture to be achieved. For the purpose of this paper, the liquid‐crystal mode used is the 45° normally black mode. 相似文献
120.
Calibrated,Registered Images of an Extended Urban Area 总被引:1,自引:0,他引:1
Teller Seth Antone Matthew Bodnar Zachary Bosse Michael Coorg Satyan Jethwa Manish Master Neel 《International Journal of Computer Vision》2003,53(1):93-107
We describe a dataset of several thousand calibrated, time-stamped, geo-referenced, high dynamic range color images, acquired under uncontrolled, variable illumination conditions in an outdoor region spanning several hundred meters. The image data is grouped into several regions which have little mutual inter-visibility. For each group, the calibration data is globally consistent on average to roughly five centimeters and 0 1°, or about four pixels of epipolar registration. All image, feature and calibration data is available for interactive inspection and downloading at http://city.lcs.mit.edu/data.Calibrated imagery is of fundamental interest in a variety of applications. We have made this data available in the belief that researchers in computer graphics, computer vision, photogrammetry and digital cartography will find it of value as a test set for their own image registration algorithms, as a calibrated image set for applications such as image-based rendering, metric 3D reconstruction, and appearance recovery, and as input for existing GIS applications. 相似文献