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In this study, the failure load values and failure mechanisms of ceramic materials filled E-glass/epoxy laminated composite plates that have two-parallel circular holes, subjected to tension forces by two-parallel rigid pins, are investigated experimentally. The composite plates used in the pin tests were produced by using three different ceramic fillers, which are Silicon Carbide (SiC), Boron Carbide (B4C), and Aluminum Oxide (Al2O3). The weight fractions of ceramic fillers in each composite plate are 5%, 10%, and 15%. For evaluating the influence of joint geometry on failure loads and failure mechanisms, the edge distance-to-hole diameter ratio, different pin-hole diameters, and the ratio of the distance between the side edge of the sample and the center of pin-hole to the hole diameter were considered as geometric parameters. The results from the experimental tests revealed that adding ceramic fillers to the composites up to a certain ratio leads to a remarkable increment in the failure load values of the composites compared to the neat (0 wt.%) composites for all weight fractions. Further, the ultimate failure load values were obtained for composite plates filled with Al2O3 ceramics in 10% weight fractions. [ABSTRACT FROM AUTHOR]

Thirteen flavanone racemates were successfully separated using a Chiralpak® IA column and isopropanol‐hexane (50:50, v/v). The mobile phase flow rate and detection wavelength were 0.5 mL/min and 254 nm. The retention times values ranged from 5.50 and 56.45 min. The values of the retention, separation, and resolution factors ranged from 0.63 to 21.67, 1.12 to 2.45, and 0.13 to 11.94. The docking binding energies ranged from −6.2 to −8.2 kcal/mol, showing enthalpy‐determined host‐guest complex formation. The molecular docking results and the experimental data were agreed well. The results showed that S‐enantiomers had stronger bindings with chiral selectors compared to R‐enantiomers. Consequently, the R‐enantiomers eluted first followed by S‐enantiomers. The reported method is highly useful to determine the enantiomeric composition of the reported flavanone in any sample. [ABSTRACT FROM AUTHOR]

This article focuses on the evaluation of the temporal and spatial effects of COVID-19 on Airbnb's supply and demand in 40 cities from 17 European countries in four regions. In terms of supply, hosts followed a wait-and-see strategy by the availability was set to 0 in the first pandemic wave, and with the second wave, the sharing activities were completely terminated by closing profiles. Hosts with entire homes and multiple listings were more willing to use calendars actively and more reluctant to close profiles than hosts with private rooms and single listings. Moreover, especially in the second half of 2020, listings in Northern, Western, and Eastern Europe suffered significant losses, while hosts in Southern Europe more actively used calendars. Airbnb demand was even more adversely affected, and the demand preferences were directed towards entire homes, where social distance might have been easier and better maintained between peers, and multiple listings, that might have been more professionally managed due to commercial concerns. Considering the dependence of entire homes and multiple listings hosts on income from sharing activities, it is thought that they may have been more affected by potential income losses than hosts with private rooms and single listings. [ABSTRACT FROM AUTHOR]