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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]

One of the most promising alternatives from the point of view technology is to fabrication of solar cells sensitized with dyes natural as they have been shown to have a relatively high efficiency at a low cost of production. In particular, the motivation of the present research work is based in addition to the above mentioned, in the constant search for new materials and processes for the manufacture of solar cells. We are particularly interested in developing methods ecological and that are friendly with the environment. The present work reports the results obtained from the study of the manufacture and characterization of solar cells type DSSC (Dye Sensitized Solar Cells) with TiO2 sensitized with organic dyes obtained from cactus fruit and hibiscus flower. The electrodes were constructed with TiO2, through the deposit of Dr. Blade, while the conductive glass counter electrodes were coated with graphite of a common pencil and commercial iodine was used as electrolyte. The cactus fruit red ink extraction was carried out by extraction alcoholic using sodium carbonate, while hibiscus ink is obtained by maceration. Optical characterization of both dyes was carried out by UV-Vis spectroscopy. Adhesive tapes were used in the construction of the TiO2 electrodes to obtain different thicknesses and find an optimal thickness to have good efficiencies. The results of the characterizations showed that the sensitized cells with better efficiency. [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]

The results of experimental studies of the behavior of the elastic tape with balls on the "Alligator 2M" experimental stand are presented. The peculiarity of the studied unit is that the tape ends are fixed in moving sliding panels performing oscillatory movements under the influence of two electric exciters. "Alligator 2M" experimental stand was created to study dynamic processes in mechanical oscillating systems with elastic links and distributed masses. [ABSTRACT FROM AUTHOR]

Meta-Cx is an innovative measuring tape inspired by the conventional measuring tape. What distinguishes them is that the conventional tape observes dimensional measurements manually by in-situ users, while Meta-Cx only requires Meta-Cx to be placed in the measuring space then space is picturised with MetaCx. The image will be analysed using a special mobile application to get the measurement whether its vertical or horizontal dimension. Meta-Cx can be used to analyze measurement using all measurement applications available in the mobile application store. The advantage of using Meta-Cx is it saves time and manpower in measuring dimensions because it only involves capturing the length or distance with a space. It makes a huge difference with the conventional tape, especially when the space is huge and requires a lot of measurements to be made. Additionally, Meta-Cx can detect unlimited vertical measurements over a limited conventional measuring tape which depends on the length of the tape. Meta-Cx has the advantage of being a gauge, but what's more important is that MetaCx can also be used as a teaching tool to expose students to adapt the use of information technology with physical equipment in the field of measurement in line with the industrial revolution 4.0 (IR 4.0). [ABSTRACT FROM AUTHOR]

In order to transfer heat with minimal leakage to surroundings and to increase efficiency energy exchanger systems are used through various methods. the output from the twin-pipe energy exchanger system is essential in terms of both system economics and efficiency. as a result, boosting the rate of thermal gradient rate is important for long-term energy growth. the goal of this study was to review heat transmission and friction properties in the horizontal double pipe heat exchanger. after thorough literature review, it has been concluded that various author has investigated different types of twisted tape insert their experimental and modeling studies and a little work is observed using twisted tape inserts with dimple configurations in a double pipe heat exchanger. [ABSTRACT FROM AUTHOR]

Adhesive bonded joints are widely used in various industries like aerospace, automotive, and shipbuilding industries. The main advantage of this adhesive bonding over conventional join methods is that it can join almost all the engineering material without any physical damage to its components. The present study deal with enhancing the adhesive bonded joint strength through the use of adherent temperature. Mild steel is considered as an adherent and Acrylonitrile butadiene styrene (ABS), ARclad 7535, and ARclad 61946 are considered as adhesives. The single lap shear (SLS) joint has been fabricated through the use of an injection mould setup. The bond strength has been evaluated using the tensile shear load capacity and pushout shear strength of the joint. From the test data, it has been observed that the temperature of the adhesive has an impact on the adhesive joint strength. The maximum shear strength has been found with ARclad 61946 tape adhesive activated with heated ABS. [ABSTRACT FROM AUTHOR]

This study investigates heat transmission and thermal performance factor characteristics in a tube with coil wire and twisted tape inserts using air as the working fluid. This study investigates heat transmission and thermal performance factor characteristics in a tube with coil wire and twisted tape inserts using air as the working fluid. The goal of this research is to improve forced convection heat transfer in tubes with and without swirl inserts and coil wire inserts for air Reynolds numbers ranging from 10.328×103 to 11.769×103. The impacts of different parameters of heat transfer are considered in this work with heat flux are constant conditions of 600 W/m2 and 800 W/m2 with using the coil wire and twisted tapes with three ratios (y/w = 3, 4 and 5). The test section is a horizontal annular passage with outer diameter 10 cm. The results showed that using coil wire inserts to improve heat transfer coefficient factors in tubes resulted in local heat transfer coefficient percentages of (5.1%) to (7.8%) with heat flux are constant conditions of 600 W/m2 and 800 W/m2, respectively. While tube with swirl inserts provide local heat transfer coefficient percentages of (3.6% to 6.1%) for heat fluxes (600) W/m2 and (800) W/m2, respectively. The obtained results demonstrate that as the twisted ratio (y/w) decreases, the mean Nusselt number and heat transfer coefficient in the tube with twisted tape and coil wire rise. Experimental results is shown, heat transfer coefficient for the coil wire when compared with that of swirl inserts tube were ranged between (10.6%) to (16.5%) and (11.5%) to (17.3%) for the heat flux (600) W/m2. [ABSTRACT FROM AUTHOR]

Investigation still on board for finding the best techniques to develop the thermal and hydraulic performance of the heat exchanger. One of the useful, practical methods for finding the modification is the numerical analysis. This numerical analysis was obtained by modelling and simulation using ANSYS FLUENT software. In this present work five elements were modelled and simulated of three different configuration models, helical tape, rectangular and triangular straight strip inserts were inserted inside the inner pipe. This simulation was employed according to the working operation conditions of the real practical double pipe heat exchanger. The results show that, the helical tape configuration demonstrated the effective enhancing technique of the heat transfer, which is improving the thermo-hydraulic performance of this type of heat exchanger in this study. According to this work, the technique of studying numerically the design enhancement of the heat exchanger can produce an excellent result and gives a good recommendation to transfer it into practical work. [ABSTRACT FROM AUTHOR]

In the technology of modern finishing works, an urgent direction is development of compositions of dry plaster mixtures using biological, energy-saving and local materials of natural origin. This article presents the results of scientific study and laboratory testing the introduction of bio-plant micro-fillers in production of dry plaster mixtures on a gypsum binder. Attempts have been made to model the composition of gypsum plaster mixes used for the internal walls of buildings and structures. As a result, mathematical models of optimal compositions with high adhesion strengths of these compositions with various surfaces have been developed, which is one of the promising directions in the field of dry construction. The influence of process and ingredient factors on the adhesive properties of plaster mixtures has been studied, and regression equations have been drawn up. [ABSTRACT FROM AUTHOR]

The features of evolution in space and time of distributions of deformation fields on the surface of the composite, reinforced with carbon tape, have been studied at meso- and macroscopic scale levels by method of correlation of digital images. The obtained pictures reflect in detail the evolution of distribution of isofields of relative deformations on the surface of composite, corresponding to different degrees of deformation action under uniaxial tension. Based on the results of the conducted studies of the carbon composite samples, numerical values of the strain concentration factor, expressing the ratio of the maximum value of deformations on the surface of the sample to the total average deformation over the entire working field of the sample, have been obtained to estimate the concentration of deformations. It has been established that the strain concentration factor is equal to 1.3 for the non-stressed carbon composite of carbon plastic tapes and 1.21 for the prestressed one. Modification of the carbon composite during prestress molding leads to a 22% reduction in stress concentration on the surface of the carbon composite, increases strength by 37.8%, deformation by 25% and modulus of elasticity by 10.25%. [ABSTRACT FROM AUTHOR]