234 research outputs found
A differential cluster variation method for analysis of spiniodal decomposition in alloys
A differential cluster variation method (DCVM) is proposed for analysis of
spinoidal decomposition in alloys. In this method, lattice symmetry operations
in the presence of an infinitesimal composition gradient are utilized to deduce
the connection equations for the correlation functions and to reduce the number
of independent variables in the cluster variation analysis.
Application of the method is made to calculate the gradient energy
coefficient in the Cahn-Hilliard free energy function and the fastest growing
wavelength for spinodal decomposition in Al-Li alloys. It is shown that the
gradient coefficient of congruently ordered Al-Li alloys is much larger than
that of the disordered system. In such an alloy system, the calculated fastest
growing wavelength is approximately 10 nm, which is an order of magnitude
larger than the experimentally observed domain size. This may provide a
theoretical explanation why spinodal decomposition after a congruent ordering
is dominated by the antiphase boundaries.Comment: 15 pages, 7 figure
Synergistic effects of polypropylene and glass fiber on mechanical properties and durability of recycled aggregate concrete
To better understand the synergistic effects of combined fibers on mechanical properties and durability of recycled aggregate concrete (RAC), different types of fibers with various lengths and mass ratios were adopted in this study. Experimental investigations were conducted to study the 28-day compressive strength and strength loss after exposed to salt-solution freeze–thaw cycles and the coupled action of mechanical loading and salt-solution freeze–thaw cycles. The microstructure was also characterized to evaluate the mechanism of this synergistic effect. To determine the effectiveness of the combined fibers on improving the mechanical properties and durability of RAC, the synergistic coefficient was proposed and applied for various combinations of fibers. The results indicate that the incorporation of fibers slightly decreased the 28-day compressive strength of RAC, but combining different sizes and types of fibers can mitigate this negative effect. Moreover, the incorporation of fibers greatly improves the freeze–thaw resistance of RAC. The combining different fibers exhibited a synergistic effect on the enhancement in properties of RAC, which could not be predicted with only one simplistic rule of fibre mixtures. In addition, microstructural characterization shows that the bonding strength of the interfacial transition zone (ITZ) between the fiber and cement matrix is mainly determined by the chemical bonding force which is due to the hydration reaction between fiber surface and cement matrix
Effects of Self-Enhancement on Eye Movements During Reading
Previous studies show that readers’ eye movements are influenced by text properties and readers’ personal cognitive characteristics. In the current study, we further show that readers’ eye movements are influenced by a social motivation of self-enhancement. We asked participants to silently read sentences that describe self or others with positive or negative traits while their eyes were monitored. First-fixation duration and gaze duration were longer when positive words were used to describe self than to describe others, but there was no such effect for negative words. These results suggest that eye movements can be influenced by the motivation of self-enhancement in addition to various stimuli features and cognitive factors. This finding indicates that the eye movement methodology can potentially be used to study implicit social cognition
FIMO: A Challenge Formal Dataset for Automated Theorem Proving
We present FIMO, an innovative dataset comprising formal mathematical problem
statements sourced from the International Mathematical Olympiad (IMO)
Shortlisted Problems. Designed to facilitate advanced automated theorem proving
at the IMO level, FIMO is currently tailored for the Lean formal language. It
comprises 149 formal problem statements, accompanied by both informal problem
descriptions and their corresponding LaTeX-based informal proofs. Through
initial experiments involving GPT-4, our findings underscore the existing
limitations in current methodologies, indicating a substantial journey ahead
before achieving satisfactory IMO-level automated theorem proving outcomes
An Evil Backstage Manipulator: Psychological Factors Correlated with Health-Related Quality of Life in Chinese Patients with Crohn's Disease
Health-related quality of life (HRQoL) is recommended as one of essential parameters to evaluate treatment effect and clinical outcome in patients with Crohn's disease (CD). Recent studies reported that psychological factors might play a role in HRQoL in Western and American CD patients. Sufficient evidences in Chinese CD patients are still unavailable. This study is dedicated to investigate the correlation of various psychological factors with HRQoL in Chinese CD patients. We prospectively collected 40 active and 40 quiescent CD patients in China and found that psychological factors, especially neuroticism and anxiety, significantly correlate with and affect HRQoL in both active and quiescent CD groups. This is the first report revealing correlation between psychological factors and HRQoL in Chinese CD patients. Therefore, we assume that our results can contribute to a better understanding of etiology and tailoring of management in Chinese patients with Crohn's disease and are beneficial to our colleagues to compare the heterogeneous characteristics of Crohn's disease in different ethnic groups
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