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The technique of micro-exfoliation has gained prominence as a highly effective and adaptable method for exploiting two-dimensional (2D) materials, such as graphene Transition metal dichalcogenides (TMDCs), Borophene, Molybdenum disulfide (MoS2), among others. This paper presents an analysis of optical images and the micro exfoliation technique, focusing on the application to MoS2 and graphene. Additionally, the study investigates the exfoliated sheet of graphene, MoS2, and their hybrid on a (111) crystal plane of silicon wafer. The micro-exfoliation technique employed for MoS2 involves a mechanical process that gently disentangles the layers of MoS2 from the larger crystal structure, resulting in the formation of ultrathin two-dimensional nanosheets. This paper comprehensively analyses the exfoliation processes' mechanisms, emphasizing the intricate relationship between van der Waals forces, interlayer bonding, and external forces. The micro-mechanical exfoliation, a fundamental technique, entails the utilization of adhesive scotch tape to remove monolayers from a large MoS2 crystal delicately. The integration of MoS2 into various applications such as electronics, optoelectronics, sensors, and energy storage devices has been driven by its exceptional properties, including its distinctive electronic, optical, and mechanical characteristics. Furthermore, the ability to adjust the bandgap of MoS2 has created novel opportunities for potential applications in the field of semiconductors. This paper provides a succinct summary of recent studies, that have concentrated on the optical characterization of MoS2 monolayers. Optical and Raman spectroscopy was employed to characterize the 2D sheets of MoS2 and its hybrid materials. [ABSTRACT FROM AUTHOR]

Heat exchangers are a common heat transfer mechanism used in a variety of applications ranging from home to industrial, aircraft, and vehicles. The aim of this research is to study the hydrothermal efficiency of a double pipe heat exchanger with helical fins on annular side of counter flow heat exchanger numerically and compare the results of a double tube with and without screw tape. The investigation begins by employing numerical modeling of helical tapes under different configurations, with different pitches (10, 15, and 20) mm and one height of 10 mm as passive heat transfer augmentation strategies, which are simulated using ANSYS 2022 R1 software. The findings reveal that the current work's numerical results and earlier research's experimental findings are in good accord. Furthermore, while using (Helical Tap Insert) (HTI), the thermal performance of the new typical is found to be better than the typical model. Furthermore, it was found that the Nusselt number achieves the highest growth when the pitch (p) is (20) mm and increases the pressure drop. Furthermore, it was discovered that when the pitch (p) is (20) mm and pressure drop is increased, the Nusselt number grows the most. Furthermore, as associated to the typical model, the total thermal effectiveness of heat exchanger for the new model has greater by 9.9%. This difference is due to the fact that in the theoretical study, ideal conditions are assumed. The experimental design, the assumptions, operating circumstances, and accuracy of the devices are taken into account. It was noted that the value of the specified percentage of hydrothermal improvement achieved the highest value in performance for the same case that was with spiral fin and pitch length (20) mm, which is 1.6% compared to the traditional model. [ABSTRACT FROM AUTHOR]

While for several decades composites have been manufactured mainly from thermosets, such as epoxy- or polyester-based resins, a clear trend towards using thermoplastic matrix systems has recently emerged. Their reversible melting behavior gives them several advantages, including better recyclability and faster and more easily automated production. Increasing the productivity of thermoplastic composite manufacturing processes requires appropriate, reliable inline quality assurance systems. Optical coherence tomography (OCT), originally developed for biomedical applications, has been proven to be a powerful tool for non-destructive testing and characterization of unidirectional (UD) fiber-reinforced thermoplastic tapes made from glass fibers. Previous offline OCT measurements on a test rig demonstrated the reliability and robustness of the method in detecting visually apparent tape defects, such as gaps and fiber breakages and – one of the most critical bulk defects – insufficiently impregnated fiber regions. In this work, inline OCT measurements were performed on stationary Polycarbonate (PC)/glass fibers (GF) UD tapes in an industrial-scale production line. Systematic experimental analyses were carried out in which the OCT sensor was moved across the tape width, and the influences of (i) single scan sampling rate, (ii) single scan averaging, and (iii) sensor travel speed on measurement accuracy and data size were evaluated. Measurement accuracy was validated using optical microscopy. Optimal sensor settings were derived to improve the inline capability of the measurement approach under real production conditions. [ABSTRACT FROM AUTHOR]

The concept of externally reinforcing damaged reinforced concrete members to restore their strength is well known today. Depending on the severity of the damage, the component is externally modified using methods such as cross-sectional enlargement, external panel bonding, external prestressing, casting, and fiber-reinforced polymer (FRP) composites. This article describes his FRP composite technique using adhesive to apply his FRP composites in fabric/tape form to defective structural members like cracks. Apart from retrofitting, this process can also be used to add strength or increase the load-bearing capacity of an element without increasing the section size. Fabrics made from carbon, glass, and basalt fibers are used for external reinforcement. Each gives different results depending on their properties, the size and type of load-carrying capacity, the type and shape of the textile fabric used, and the different winding methods. To this end, in this study, a four-point load system was tested based on load-bearing reinforced concrete beams wrapped with glass fiber composite fabrics of various patterns. The focus of the article is on basalt fiber fabric and whether it is a better choice as a retrofitting material than others. [ABSTRACT FROM AUTHOR]

The research presents the results of experimental studies on the features of printing on composite biodegradable films made from a mixture of polyethylene and thermoplastic starches. Thermoplastic starches were produced based on native starches of different kinds by processing them in laboratory extruders of Brabender and MashPlast (Russia). Biodegradable hybrid compositions (BHCs) in the form of strands, pellets, and films were produced by mixing thermoplastic starches with polyethylene in extruders. The edge wetting angle of the BHC films was determined using a laboratory unit equipped with Image software (Russia), and the surface tension of the BHC films was determined using test ink (Germany). Modification of the surface of the BHC films was carried out in a laboratory unit using the method of film treatment with a "corona" discharge. The adhesion interaction of the paint coating on the BHC films was evaluated by the lattice incision method and the adhesive tape method. Changes in the chemical structure after "corona discharge" modification were determined by Fourier infrared spectroscopy. It was found that the surface properties of biodegradable hybrid compositions change when treated with "corona discharge" and the composite polymer films become suitable for the printing process, but during the treatment in the "corona discharge" plasma the BHCs do not change into the electret state. [ABSTRACT FROM AUTHOR]