The microstructural and strength evolution of an additively manufactured Al-8.6Cu-0.5Mn-0.9Zr alloy upon aging at 300, 350, and 400? is investigated. The strengthening phases of the alloy evolve significantly upon agi...
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The microstructural and strength evolution of an additively manufactured Al-8.6Cu-0.5Mn-0.9Zr alloy upon aging at 300, 350, and 400? is investigated. The strengthening phases of the alloy evolve significantly upon aging, with breakdown and spheroidization of the interconnected theta'-Al2Cu network, dissolution of metastable theta'-Al2Cu precipitates, and precipitation of nanometric L1(2)-Al3Zr from a matrix supersaturated in Zr. In the peakaged states, the alloy displays a favorable combination of strength and ductility, with a room-temperature yield strength of 314-341 MPa and ductility of 11-13%. The measured yield strengths for microstructures with different aging treatments are compared to predictions of yield strengths from grain boundary, solid solution, and particle strengthening contributions. The observed strain hardening behavior is related to fundamental precipitate and dislocation interactions. Comparison between predicted and measured strength values indicates a continued need for strengthening models specifically developed for the heterogeneous microstructures of additively manufactured alloys.
Foamed asphalt binders are increasingly being used to produce warm mix asphalt. This paper presents the findings from a study conducted to (1) identify a repeatable and accurate method to characterize the quality of a...
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Foamed asphalt binders are increasingly being used to produce warm mix asphalt. This paper presents the findings from a study conducted to (1) identify a repeatable and accurate method to characterize the quality of asphalt binder foams, and (2) use this method to evaluate the influence of water content, binder type, and foaming device on the quality of foamed binders. Laser and ultrasonic distance-measuring tools were used in combination with digital imaging of the foamed surface to quantify and better understand the expansion and decay of foamed asphalt binders over time. Measurements obtained from these methods were used to evaluate the extent and stability of foams produced using three different asphalt binders at three water contents and two laboratory foaming devices. Rheological properties and moisture content of selected binder residues were also measured. Results indicate that both the laser- and ultrasonic-based methods were promising in terms of their ability to provide a repeatable and detailed history of the change in volume of the foamed asphalt binder as the foam collapses. It was also shown that water content and binder type have a significant influence on the maximum expansion ratio and rate of collapse of foams. Higher water contents were associated with higher expansion ratios but also faster rates of collapse. The two foaming devices used in this study produced foams with similar properties. Rheological tests conducted on foamed binder residues revealed that the foaming process slightly increased the high temperature continuous performance grade (PG) of the binder. (C) 2014 American Society of Civil Engineers.
The ground state potential energy surface for HCO+ has been investigated theoretically. A large fraction of the electron correlation is included by multi reference internally contracted configuration interaction from ...
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The ground state potential energy surface for HCO+ has been investigated theoretically. A large fraction of the electron correlation is included by multi reference internally contracted configuration interaction from CASSCF reference wavefunctions using large orbital expansions. The origin of the potential is then shifted and the force constants scaled to reproduce all spectroscopic data available for five isotopically substituted species. The estimated equilibrium geometry and force constants agree closely with the results of previous computations. Variational calculations of vibrational and rotational frequencies for transitions up to J = 4 <-- 3 have been performed, with accuracy which is typically +/- 2 cm(-1) for vibrations and +/- 20 MHz for most rotations. From computed and experimentally available ground state rotational and I-doubling constants estimates have been made of the equilibrium geometry (r(e) (C-H) = 1.0919 +/- 0.0009 Angstrom and R(e) (C-O) = 1.1055 +/- 0.0003 Angstrom) and of the most important anharmonic interactions.
Mitochondrial oxidative metabolism was examined in two infants with Pompe's disease. The clinical diagnosis was confirmed by the demonstration of intralysosomal glycogen accumulation and a deficiency of acid alpha...
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Mitochondrial oxidative metabolism was examined in two infants with Pompe's disease. The clinical diagnosis was confirmed by the demonstration of intralysosomal glycogen accumulation and a deficiency of acid alpha-D-glucosidase in muscle biopsies. Light and electron microscopy studies demonstrated a normal number of mitochondria with normal ultrastructure, Spectrophotometric measurements revealed that the specific activities of citrate synthase and the partial reactions of electron transport were markedly elevated in the skeletal muscle homogenates prepared from both infants with Pompe's disease when calculated as micromoles per minute per gram wet weight of tissue. However, when respiratory chain enzyme activities were expressed relative to citrate synthase as a marker mitochondrial enzyme, a different pattern emerged, in which all Pompe muscle respiratory enzymes, except complex IV, were decreased relative to control subjects. These observations demonstrate that caution should be exercised when analyzing and interpreting data obtained from tissue homogenates in general and, in particular, in those prepared from tissues in which the wet weight of tissue may be altered, for example, by pathologic accumulation of carbohydrate or lipid. (C) 2000 by Elsevier Science Inc. All rights reserved.
Visual question answering (VQA) is a challenging task that reasons over questions on images with knowledge. A prerequisite for VQA is the availability of annotated datasets, while the available datasets have several l...
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Visual question answering (VQA) is a challenging task that reasons over questions on images with knowledge. A prerequisite for VQA is the availability of annotated datasets, while the available datasets have several limitations. 1) The diversity of questions and answers are limited to a few question categories and certain concepts (e.g., objects, relations, actions.) with somewhat mechanical answers. 2) The availability of background knowledge or context information has been disregarded with just images, questions and answers being provided. 3) The timeliness of knowledge has not been examined, though some works may introduce factual or commonsense knowledge bases, e.g., ConceptNet, DBPedia. In this paper, we provide an Event-oriented Visual Question Answering (E-VQA) dataset including free-form questions and answers for real-world event concepts, which provides context information of events as domain knowledge in addition to images. E-VQA consists of 2,690 social media images, 9,088 questions, 5,479 answers, and 1,157 news media articles for references being annotated to 182 real-world events, covering a wide range of topics, such as armed conflicts and attacks, disasters and accidents, law and crime. For comparisons, we investigate 10 state-of-the-art VQA methods as benchmarks.
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