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The objective of the study was to synthesize and evaluate vinyl ester resin composites reinforced with pineapple fiber and cellulose, which is prepared by the Amaranthus viridisroot. This study also examined the mechanical, fatigue, and dynamic mechanical behavior (DMA) of the composites and how the silane treatment process affected the properties. The cellulose was synthesized via the modified chemical route, and the composites were made using the hand lay-up technique. The results of this investigation demonstrated that the fiber addition improved the mechanical, fatigue and, dynamic mechanical properties (DMA). The highest values for tensile and flexural strength, Izod impact toughness, interlaminar shear stress (ILSS), and compression strength were about 164 MPa, 192 MPa, 5.64 J, 23.2 MPa, and 176 MPa for VPC3 composite designation, respectively. Moreover, maximum fatigue life counts for 30%, 60%, and 90% of UTS for the composite designation VPC3 which is recorded up to 38,134, 33,081, and 27,131, respectively. Similarly, the composite designation VPC4 improved the storage modulus and loss factor of about 108.3% and 25.78% compared to the plain resin. These composite materials, which have good mechanical characteristics and fatigue properties, could be used in industrial, household, and automotive applications such as manhole covers, gratings, and exterior designer pipes.

Semi organic compounds enable several structural and bonding methods for the molecular engineering of novel materials. The optical analysis, methyl orange doped L‐lysine sulfate (MLLS) is an innovative NLO material enabling the rate of frequency up change for stronger systems with lasers in the UV range with clear absorption. With this experimental studies the theoretical studies of the L‐lysine sulfate and its molecules were studied using Gaussian09w software. X‐ray analysis, UV, FTIR, NMR, Mulliken Charges, HOMO‐LUMO, MEP and some related thermodynamic properties were studied. The chosen nucleophilic site is symbolized by the color red, the more popular electrophilic site has been highlighted during MEP mapping. Spectroscopical and thermodynamical properties related to functional behavior of molecules were also discussed with obtained results.

Corneal allogeneic intrastromal ring segments (CAIRS) refer to the placement of allogeneic rings and segments in intrastromal channels within the cornea. Currently, a deepithelialized donor cornea is used as the allogeneic source for CAIRS and the cut ring is turned sideways and implanted so that the thickness can be varied by varying the distance between the concentric trephine blades. In addition, to obtain a greater effect, CAIRSs are preferred to be implanted with the Bowman layer (BL) facing the corneal apex and posterior stroma facing limbally. Being flexible tissue, it is, however, important to prevent twisting and to maintain correct orientation. We describe a simple technique of marking the BL with a gentian violet surgical marker to simplify CAIRS insertion. BL marking allows easy visibility of twists and helps identify improper orientation, thus allowing correct insertion of CAIRS.

The main objective of this study is to investigate the effect of gas metal arc welding (GMAW) and cold metal transfer arc welding (CMTAW) processes on microstructure and mechanical properties of AA8011-H18 aluminum alloy joints. The AA8011-H18 alloy sheets of thickness 3 mm were welded in butt joint configuration using conventional GMAW and CMTAW processes. The optical microscopy was employed for analyzing the microstructure of weld metal (WM) and heat-affected zone (HAZ) of the developed joints. The tensile properties and hardness of welded joints were evaluated using universal testing machine (UTM) and Vickers microhardness testing machine. The GMAW and CMTAW joints disclosed the joint efficiency of 58.33 % and 75.98 %, respectively. The CMTAW joints showed 30.25 % and 27.28 % improvement in tensile and yield strength compared to GMAW joints. However, there is a loss of 20 % ductility in CMTAW joints compared to GMAW joints. The superior tensile strength of CMTAW joints is correlated to microstructural refinement of WM and reduced grain growth in HAZ. It alludes to the wire retraction mechanism, which help to regulate the droplet transfer and lower the heat input.

A major issue limiting the successful deployment of deep-learning algorithms in geophysical applications is their inability to generalize to new contexts. Regarding the quantitative precipitation estimation (QPE) from the Global Precipitation Measurement (GPM) satellite constellation, the GPM microwave imager (GMI) contains enough co-located brightness temperatures (TBs) and rain rates data to train a deep-learning inverse model to retrieve precipitation intensity. However, the difference in instrumental configurations makes it impossible to directly apply this inverse operator to another space-borne radiometric imager. A domain adaptation is thus necessary to solve the domain shift problem encountered when applying the model trained on one satellite to another satellite. The present article tests a method to map the SSMI/S data to the GMI data. In the absence of sufficient paired images between the two satellites, we applied a Cycle Consistent Generative Adversarial Network (CycleGAN), which allows for an Unsupervised Domain Adaptation approach. Evaluating the quality of adapted images is a complex problem. This article employs two tactics: a brief evaluation of adapted radiometric images and a qualitative/quantitative evaluation of rain retrieval. Over several case studies, the results show that the domain adaptation step produces adapted SSMI/S images that retain the majority of the rain structure. Next, the rain detection score and intensity bias are then compared using 847 overpasses. The same analysis is carried out over mainland France by comparing the results with rainfall products supplied by Météo-France. In both comparisons, the adapted images allow the inverse operator to provide a better score in rain detection and intensity.

Single-atom catalysts (SACs), including metal-metal-bonded bimetallic ones named single-atom alloys (SAAs), have aroused significant interest in catalysis. In this article, the catalytic mechanism and bonding analysis of CO oxidation reaction on bimetallic gold-palladium (Au-Pd) model of single atom alloy Au37Pd1are investigated by using quantum chemical calculations. The molecular geometries and adsorbate/substrate binding energies of CO@Au-Pd, O2@Au-Pd and CO/O2@Au-Pd configurations are identified. The core-shell structure is confirmed to be the most stable structure for Au-Pd SAA, where the Pd atom prefers to situate at the core site. Charge transfer from the Pd atom to the Au atoms has been confirmed to stabilize the structure. According to the binding energy and chemical bonding analysis, both CO and O2prefer to bind to the Pd atom at the hex site with low coordination number. The formation of new co-adsorption species is identified, in which vertical and parallel bridging adsorptions of CO and O2on the Au-Pd bonds are observed. CO oxidation on Au-Pd SAA is found to be feasible with low energy barriers and follows the Langmuir-Hinshewood (L-H) mechanism. Our work offers insights into the significant role of single atom of the SAAs in catalytic reactions and can provide evidence for designing new SAAs with high-performance catalytic activities.