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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]

At present, the verification method of steel tape has characteristics of high labor intensity, low working efficiency and low measuring accuracy. To solve these problems, an automatic steel tape verification system is built in this paper. This system takes the stainless steel as the calibration platform, uses the CCD camera and image processing technology to achieve the indication errors between lines. It realizes the automatic verification through precise motion control technology and special measuring software. This device completes the verification by trolley motion control and CCD image acquisition, and carries on the image recognition to analyze errors and evaluate results. Experiments show this device has comprehensive functions, high level of automation, practical application value and broad market prospects. [ABSTRACT FROM AUTHOR]

Thermal energy is very lots beneficial in the human day by day lifestyles whereas it is transformed from solar strength. One of the green methods of garnering warm energy is from the sun plate collector. This paper emphasizes an experimental observe of Nusselt range (Nu), Friction element (fr) and Thermal overall performance (η) of the Double-V-Trough solar Collector (DGVT) ready with plain twisted tape (PTT), horizontal wing twisted tape (HWTT) and vertical wing twisted tape(VWTT) bets under one of a kind turning situations (Y=3& 6) and same working mode. DGVT's warmness transfer capacity is better than an unmarried glass V-Trough sun collector (SGVT) with eight.84%. The usage of the double glazing glass within the V-Trough collector reduces the thermal coefficient which improves the thermal performance. Empirical data has been validated with basic equation and its associated errors are less than ± 14.79% & ± 4.17% for Nu and respectively. The experimental results showed that Nu, frand η in DGVT associated with HWTT were significantly higher than in the tube equipped with VWTT and PTT. The additional fluid disruption close to the tube wall persuaded by the wing and the secondary flow near the tube wall represented by HWTT and VWTT relative to the induced by PTT was determined as the cause of enrichment. Correlations are developed for Nu and to match experimental results and deviation falls within ± 9.25% and ± 7.18%, respectively. [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]

The advent of Automated Fiber Placement (AFP) systems have aided the rapid manufacturing of composite aerospace structures. One of the challenges that AFP systems bring is the variability of the deposited prepreg tape layers, which are prone to gaps, overlaps and twists. The current detection method used in industry involves halting fabrication and performing a time consuming visual inspection of each tape layer. Typical AFP systems use a quartz lamp to heat the base layer to make the surface tacky as it deposits another tape layer. The innovation discussed in this paper is to use the preheated base layer as a through transmission heat source and inspect the newly added tape layer in situ using a thermographic camera mounted onto the AFP structure. Such a system would not only increase manufacturing throughput by reducing inspection times, but would also aid in process development for new structural designs or material systems. To this end, a small thermal camera was mounted onto an AFP robotic research platform at NASA, and thermal data was collected during typical and experimental layup operations. The data was post processed to reveal defects such as tow overlap/gap, wrinkling, and peel-up. Defects that would have been impossible to detect visually were also revealed in the data, such as poor/loss of adhesion between plies and the effects of vacuum debulking. This paper will cover the results of our experiments, and the recent progress on the data reduction algorithms in preparation for machine learning development. [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]

Reflected grid deflectometry is an optical method of vibration analysis relying on specular reflections to create amplifications of measured deformations in a planar test structure, resulting in high resolution slope and deflection plots of the test surface. Therefore, the structure under test is required to have a reflective surface. Application has so far been limited to ideal mirror-finished planar objects. An experiment is constructed to test the effectiveness of add-on reflective material on non-reflective planar panels for deflectometry measurements, using a collection of adhesive tapes, film, and spray. The structural deflection due to a point impact is measured, and results for each add-on material are then compared and discussed. The findings indicate that tapes, while cheap, are manufactured without strict tolerances on thickness, causing distortions in the reflected image and therefore the deflection plots. Film can be applied with limited success, but further testing is required to refine the application method. Spray-on reflective material, which is only applicable on transparent surfaces, produces deflection plots comparable in quality to those of an ideal mirror. [ABSTRACT FROM AUTHOR]

Modern high-performance materials such as fiber-reinforced plastics are currently indispensable in various industries. Despite higher melt viscosity, recent developments allow the use of thermoplastic materials as a matrix material. Using the pultrusion process, unidirectional thermoplastic tapes can be produced continuously. The materials used in the production of these tapes undergo a quality assurance process in their production. Tapes, however, are often only tested destructively or optically. It would therefore be desirable to have a non-destructive testing method that can detect cracks, inclusions and changes in the impregnation quality quickly and without contact. To determine the impregnation quality, four CFRP tapes with slightly different degrees of impregnation were examined using slanted air-coupled ultrasound transmission. The test specimens were scanned in meandering form and all data were evaluated by means of various specially programmed analysis programs. A tape was arbitrarily selected as OK-Tape and the maximum/minimum amplitude, the mean of the amplitudes and the standard deviations of the entire C-Scan were defined as standard. With an automated evaluation software, quality points could be given for each tape, which were calculated depending on the data of the OK-tape. Using this method, small differences in the total area of the tapes as well as local inhomogeneity, such as holes, were detected. This procedure demonstrates how small differences in tape quality can be detected, although a calibration to an OK-tape is required. [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]

Superconducting magnets allow obtaining high magnetic fields. The application of tapes with high temperature superconductors enables them to operate in liquid nitrogen, thus decreasing operational costs. However, ceramic structure of the tapes is prone to mechanical damages, which can decrease critical current density and lead to malfunction of the device. This work presents the results of the analysis of the operation of a faulty superconducting magnet. Preliminary design considerations and expected performance are calculated numerically. The experimental results show the degeneration of the structure of the tape. Possible causes of damage and available remedies are discussed. [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]

For this project, it is focused on the improving design and analysis measuring tape. Measuring tape is not a new thing to us. It is a high demand product in surveyor industry. Currently, they are a lot of measuring tape design are selling in the market. The objectives of this project are to design the measuring tape and to decrease the time to assembly the product. Besides, it also learn on to analyse the cost of manufacturing of the product. The design of measuring tape is using CAD software and then transfer to Finite Element Analysis (FEA) to analyses the capabilities of part design. At the end of this project, this research will give understanding about design using CAD software and do analysis that improved the measuring tape. [ABSTRACT FROM AUTHOR]

This project is designed and evaluated to develop the tape measurement instrument. Measuring tape is not a new thing for us. It is a high demand product in the surveyor industry. Currently, they are a lot of measuring tape designs selling in the market. This project is intended to achieve the new measuring tape design and decrease the time to assembly the product. Besides, it also learns to analyse the cost of manufacturing of the product. The CAD approach has been used to design a measuring tape and CAE, such as Finite Element Analysis (FEA), to identify the component capabilities and strengths. This study will include an understanding of CAD software design and perform analysis that strengthens the measuring tape at the end of this project. [ABSTRACT FROM AUTHOR]

Current study is focused on automated fiber placement technology with the purpose of finding possibilities to offer suitable laminating equipment for small and medium sized companies. The temperature, consolidation pressure and consolidation duration are considered as laminating parameters (design variables). The experimental study has been performed and mathematical model developed in order to establish relation between the shear strength and laminating parameters. [ABSTRACT FROM AUTHOR]

Besides the aerospace industry, fiber reinforced plastics have also spread towards many further applications such as automotive or civil engineering. Their superior strength and stiffness to mass ratio made them the number one material for achieving high performance. Especially continuous fiber reinforced plastics allow for the construction of structures which are custom tailored to their mechanical loads. The two main constituents of CFRP are carbon fibers and matrix. Two possibilities for matrix material exist: thermosetting and thermoplastic matrix. While thermosetting matrix may yield better properties, thermoplasticity opens a wide range of applications due to weldability and compatibility to e.g. thermoplastic injection molding materials. In this work an inline monitoring system was developed for quality assurance of continuous fiber reinforced, thermoplastic CFRP tapes using air-coupled ultrasound. This system is independent of tape thickness and tape width due to an adaption of the angle of incidence. By slanted incidence of the ultrasound on the tape surface, guided waves were excited in the material in fiber direction and perpendicular to the fiber direction. Artificial defects – fiber cuts, matrix cuts, circular holes, low velocity impacts from tool drop, and sharp bends – were produced. Experiments on a stationary tape showed good detectability of all artificial defects by guided waves. Also the effects of variation in material properties, fiber volume content and fiber matrix adhesion were examined, to allow for quality assessment. For validation of the monitoring system, an apparatus containing one endless loop of CFRP tape was constructed and built to simulate the pultrusion process. Several methods were investigated regarding the scanning path of single channel ultrasonic transducers in order to achieve 100 % testing of the tape. For final validation of the monitoring system a Probability of Detection (POD) analysis was conducted and analyzed. [ABSTRACT FROM AUTHOR]

Industrial processes require efficient operation unit that provide minimum mass and heat waste. Heat waste minimization can be obtained through heat integration by utilizing heat exchanger network. Heat exchanger network consist of heat exchanger that connected in series parallel connection. Heat exchanger as one of thermal operation unit transfer heat between two or more fluids through convection and conduction phenomenon. There are some types of heat exchanger available in the market such as shell and tube heat exchanger. Shell and tube heat exchangers are commonly used throughout the process industry to transfer heat. Some of design variables in Shell and tube side of heat exchanger should be optimized in order to achieve the best performances and lowest cost heat exchanger. In the optimization require three components i.e. heat exchanger model, problem formulation and optimization technique. In this research, the objective function is minimizing cost by constraint the heat transfer area and heat duty. The models use some of first principle and empirical models. Generalized Reduced Gradient (GRG) is utilized to solve this optimization problem. The Optimization result shows the design of heat exchanger by using coil wire insert technology provides the lowest cost compare to modern technologies of heat exchanger and conventional of heat exchanger by reducing 50% cost and then afterwards helical baffle 30.75% and then internal fins 30.51% and the least is twisted tape inserts 8.09%. [ABSTRACT FROM AUTHOR]

This work is devoted for analysis of perforated steel tape, in this case also manufacturing remnant, usage possibility. There are defined physically-mechanical properties and geometrical characteristics for different types of tape. The perforated tape samples tension strength is noticed in the amplitude of 168 to 921 MPa, compressive strength of profiled stands - 350 MPa, but surface hardness in the amplitude of 830 to 3030 MPa. It is proved that tape by its physically - mechanical and esthetical features can be effectively used as a design element, reinforcing and constructive material in the construction processes. Effective solutions for use of perforated steel tape are form elements, reinforcing in reinforced concrete constructions and brick masonry, floor spacers, elements of wall constructions and other construction load-bearing elements. [ABSTRACT FROM AUTHOR]