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As two important industrial manufacturing materials, ceramics and metals have their own advantages and disadvantages in terms of physical, chemical, and mechanical properties. The field of material manufacturing has witnessed efforts to develop technical processes that can properly combine these two alloys, aiming to effectively use their respective advantages. The welding technology for ceramics and metals, as a research topic with broad prospects, is comprehensively and deeply analyzed in this review. The current research progress in this field is analyzed from different process perspectives such as fusion welding, brazing welding, diffusion welding. By using appropriate intermediate materials between these two materials, the residual stress and brittle intermetallics near the interface of the transition joint can be minimised by solving the thermal expansion mismatch, reducing the bonding temperature and pressure.

This study focused on preparation of microfibers from bamboo culms using steam explosion with and without chemical treatments, and utilization of the isolated fibers in formation of bamboo paper fabricated with nanofibrillated cellulose (NFC). Compared with those obtained from the steam explosion alone (S), the bamboo microfibers isolated using the steam explosion followed by bleaching process (S/A) exhibited a significantly reduced fiber width of 7.5 μm and a markedly increased cellulose content of 97.85%. The S/A fiber showed an increased decomposition temperature, corresponding with lower contents of hemicellulose and lignin than those of the S fiber. The S/A microfibers were subsequently proceeded to paper formation. Physical and mechanical properties of the paper with an introduction of different NFC concentrations (0–50 wt%) were investigated. The linear relationship between the density, porosity and mechanical properties of the paper and NFC contents was observed. The more the NFC content, the greater the density and the lower the porosity the paper exhibited. At 50 wt% NFC, the paper density increased to 0.64 g cm−3, and the paper porosity decreased to 57.0% whereas the paper without NFC showed a density of 0.39 g cm−3 and porosity of 73.6%. Tensile strength and strain of the paper composed with 50 wt% NFC were 10-fold and 3-fold, respectively, greater than those of the paper without NFC. The addition of NFC could manifest paper mechanical properties and porosity within the paper structure, which would be useful for scaffold and membrane applications. Keywords: Bamboo, Mechanical properties, Paper, Nanofibrillated cellulose, Steam explosion, Microfibers, Nanofibers

Waste Foundry Sand (WFS) is the by-product of casting industries and is utilized to make molds. Some minerals, such as clay particles or chemical admixtures such as phenolic resins, are used to bond silica sand grains and shape the mold. Preventing environmental impacts such as WFS landfilling, many researches have been conducted to find an appropriate way for reclamation and evaluation of its cleaning. Due to the color changes during this process, image processing is helpful for an estimation of reclamation progress. In this paper, thermal reclamation method and Response Surface Methodology (RSM) are used as the most appropriate way of reclamation and design of experiments, respectively. Samples are heated at different temperatures for a variety of time durations. The color changes of samples are measured using image processing technique by detection of RGB (Red, Green, Blue) color coordinate system parameters changes (ΔRGB). The results of TCLP (Toxicity Characteristic Leaching Procedure) tests reveal that phenolic compounds are removed during the reclamation process, which causes WFS color changes from black to almost white. On this basis, a linear model is developed to predict RGB values relative to time or temperature variations. Results approve that an investigation on ΔRGB values provides a precise estimation of WFS grains reclamation level (less than 10 % error) to guide its reuse within the foundry industries. Keywords: Reclamation, Waste Foundry Sand, Response surface methodology, Waste management, ΔRGB, Image processing

Now-a-days, many researchers use priceless industrial or agricultural products as the main raw material for the construction industry. However, these wastes are inexpensive and easily available everywhere to utilize for commercial purpose and also helpful in reducing the environmental pollution. This experimental study aimed to evaluate fresh (workability) and mechanical properties (density, permeability and split tensile strength, compressive and flexural strength) of concrete with 0%, 5%, 10%, 15% and 20% of millet husk ash (MHA) and 10%, 20%, 30% and 40% of wheat straw ash (WSA) to replace Ordinary Portland Cement (OPC) and sand respectively at conditions: a) concrete with MHA; b) concrete with WSA; and c) concrete with MHA and WSA. 525 concrete specimens were prepared with 1:1:2 mix proportions with 0.55 water/cement ratio and cured at 28 days. The increase of combined MHA and WSA contents to produce concrete decreased the workability of fresh concrete and decreased density and permeability of hardened concrete. Compressive strength, split tensile and flexural strength are increased with addition up to 15% of MHA and 30% of WSA combined. Same behavior is observed to compressive strength after chloride attack. Those results were better when compared to those of conditions a) and b). Therefore, it is possible to produce eco-friendly concrete with MHA replacing OPC and WSA replacing sand, individually or combined, which contributes to less environmental impact. (c) 2021 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

For a long time, ilmenite floatability in strongly acidic pulp has not received enough attention, which violates compliance requirements for the industrial production of ilmenite concentrate. In this present study, decanoic acid was found to be an effective collector, to float ilmenite in strongly acidic pulp (especially for the pH range from 3 to 6). The combination of decanoic acid and oleate proved to be significant in improving ilmenite floatability within a broad pH range, and especially at a pH around 4. The most synergistic and effective result occurred when the ratio of decanoic acid and oleate was 1:2, and the difference in flotation recovery of ilmenite and titanaugite was also increased at a pH around 4. Therefore, the collector scheme with a 1:2 ratio of decanoic acid and oleate was significant in strengthening ilmenite flotation behavior and its selective separation. Keywords: Ilmenite, Decanoic acid, Oleate, Acidic floatability

Sugar palm (Arenga pinnata) fibre is considered as a waste product of the agricultural industry. This paper is investigating the isolation of nanofibrillated cellulose from sugar palm fibres produced by a chemo-mechanical approach, thus opening a new way to utilize waste products more efficiently. Chemical pre-treatments, namely delignification and mercerization processes, were initially involved to extract the sugar palm cellulose. Then, mechanical pre-treatment was performed by passing the sugar palm cellulose through a refiner to avoid clogging in the subsequent process of high pressurized homogenization. Nanofibrillated cellulose was then characterized by its chemical properties (Fourier transform infrared spectroscopy), physical morphological properties (i.e. scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis), and thermogravimetric analysis. The nanofibres were attained at 500 bar for 15 cycles with 92% yield. The results showed that the average diameter and length of the nanofibrillated cellulose were found to be 5.5 ± 1.0 nm and several micrometres, respectively. They also displayed higher crystallinity (81.2%) and thermal stability compared to raw fibres, which served its purpose as an effective reinforcing material for use as bio-nanocomposites. The nanocellulose developed promises to be a very versatile material by having a huge potential in many applications, encompassing bio-packaging to scaffolds for tissue regeneration. Keywords: Agricultural waste, Sugar palm fibre, Nanocellulose, Sugar palm nanofibrillated cellulose, High pressurized homogenization (HPH)

Innovative approaches are under research to produce sustainable bricks from waste materials in order to minimize the significant environmental impacts of conventional brick industry. In this study, geo-polymerization technique was used for the first time to produce sustainable light-weight bricks from cigarette butts (CBs) and coal ash. Various Na2SiO3: NaOH and coal ash: activation liquid ratios were studied to be able to obtain well-formed bricks. The CBs were added in coal ash in two ways: either in dry form or previously soaked in the activation liquid before they were mixed with the coal ash. The percentage of CBs mixed in coal ash was varied between 5% and 15%. The density, compressive strength and water absorption capacities of the geo-polymer bricks were elucidated at time intervals of 7, 14 and 28 days. The results showed that, bricks produced with Na2SiO3: NaOH ratio of 2:1, (coal ash and CBs): activation liquid ratio of 3.5:1 and 15% treated CBs achieved a low density (1563 kg/m3) while sustaining its compressive strength (11.1 MPa) complying with the standards. In addition, lower water absorption was obtained with the bricks containing treated CBs in comparison to the ones with untreated CBs. In conclusion, geo-polymerization shows a high potential as a sustainable method for the light-weight brick production from CBs and coal ash.

Valorization of plant wastes to constitute biodegradable ecofriendly composites grabbed ever increasing interest since 2-3 decades. Moreover, dealing with substantial amount of Nile rose plant has been growing challenge, especially during increasing demand on water. The aim of this research is to investigate the morphological, mechanical, and chemical properties of gelatinized starch (TPS) and its Nile Rose fibers (NRF) filled composites. The optimum combination of mechanical and chemical properties was obtained for sample containing 60% NRF and further increase in the fiber content shows drastic deterioration in mechanical properties. Raising fiber fraction boosted up hardness, water uptake, and chemical resistance. IR and XRD are corresponding with weight content and show up good adhesion between fiber and matrix. 60% NRF shows comparable properties to starch based composite reinforced with either palm or bagasse fibers; which recommends this sample to be potential candidate as a biodegradable panel for multitude of applications, especially automotive and decorative applications.

The shifts in quality of global reserves of iron ore, as well as the progressive advances in environmental legislations, are tendencies that have motivated researches on the usage of iron and carbon-bearing residues in the production of sinter for blast furnace ironmaking. These residues, however, are commonly limited in use due to their physical (particle size distribution) and chemical (heavy metals, alkali and zinc contents) properties as compared to sinter feed. In that sense, it is necessary to verify the impact of these materials on sinter quality and on sintering process parameters. In order to assess the recycling potential of residues via sintermaking, mixtures with increasing proportions (4.5–50%) of iron and steelmaking residues were prepared and tested in controlled laboratory conditions representing those of the sintering machine. The effect of residues on sinter mineral phases and chemical quality was evaluated and showed few differences in sinter quality for a mixture resulting from recycling 100% of a plant’s residue generation (4.5% of the mix). The greatest impact was an increased presence of wustite in the produced sinter, beyond 25% of residues in the mixture. The results indicated that there are opportunities, in the industry, for increasing the recycling of residues via sintermaking. Keywords: Sintermaking, Residues, Iron Ore, Recycling

Iron ore tailings with particle sizes smaller than 297 μm were used in this experiment. These tailings were obtained from Mineração Usiminas, Brazil. The objective of this study was to evaluate the performance of the reverse cationic flotation of these iron ore tailings, which in turn would allow us to deepen the understanding of the depressant action of ground corn and cassava flour. Bench flotation tests were carried out varying dosages of depressants and pH values of the conditioning processes of the same in 8, 9 and 10. The zeta potential measurements were performed on hematite in the presence of these different depressants. Cassava flour was found to more significantly reduce the zeta potential than ground corn, and it also altered the isoelectric point of hematite. Nevertheless, the results of the bench flotation tests did not result in a clear distinction between the effect of ground corn and cassava flour. The iron recoveries increased with reduction of pH conditioning from 10 to 9 and 8, but these also led to a slight increase in the silica content of the iron concentrate. Keywords: Iron ore tailings, Flotation reagents, Flotation depressants, Cassava flour, Ground corn

The traditional processing of kaolin is achieved by dispersion of the mined ore and classification by multistage hydrocyclone plants. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back into the quarry. In this research, recovery of kaolinite from tailings of Zonouz kaolin washing plant, which is located in Iran was investigated by flotation and flotation- flocculation. Flotation experiments show that the flotation of kaolinite from the tailings is better in an acidic than in an alkaline medium containing cationic collectors. Flotation under acidic condition causes problems such as equipment corrosion at industrial scale. As a result, the cationic flotation of kaolinite is enhanced by addition of polyacrylamide as a flocculant. The results showed flocculation by polyacrylamide improved flotation of kaolinite within a range of pH. With 300 g/t dodecylamine, 500 g/t aluminum chloride, 50 g/t pine oil (frother), 15 g/t polyacrylamide, at pH = 7 and without de-slimming a product has 37.19% Al2O3, 54.19% SiO2 and 34.43% mass recovery was archived. Keywords: Kaolinite, Flotation, Flocculation, Cetylpyridinium chloride, Dodecylamine, Aluminum chloride, Polyacrylamide

To extract carbon dioxide from the air stream, a venture detergent on a semi-industrial scale was used in this article. The effects of various parameters, such as the inlet air flow to the Venture detergent, the solvent flow, the effect of the form of magnetic field and its strength on the distribution of solvent droplets, the pressure drop in the bottleneck of the Venture detergent, the solvent wastage during the washing process, are presented in this paper. Using aqueous nanofluid solvent/carbon oxide-nanotubes in the presence of surfactants SDS and CTAB, the absorption of carbon dioxide was investigated. The findings of the possible DLS and Zeta experiments have shown that the nanoparticles used in this paper are stable in the vicinity of the surfactant and that their surface charges are sufficient to keep the nanoparticles from binding together in the base fluid. The findings revealed that the ratio of local to moderate flux decreases with increasing the radius of the Venture detergent throat, which means that much of the water in the middle of Venture flows. The results have revealed that the droplet distribution diagram shows that the distribution of solvent droplets can be more uniform by reducing the solvent volume flow, so low flows are ideal for the separation process in the absence of a magnetic field and also The findings also revealed that nanoparticles inserted would almost always improve the efficacy of adsorption relative to the base fluid (along with surfactants). In each nanofluid, the maximum adsorption efficiency appears in a specific weight fraction of the nanoparticles. 1: 3, 1: 1, 3: 1, respectively) in the presence of CTAB surfactant in nanoparticle weight fractions of 0.5, 0.1, 0.05, 0.01 and 0.5%, respectively, and for in the absence of surfactant, the maximum amount of adsorption was observed in weight fractions of 0.5, 0.1, 0.05, 0.01, and 0.5%, increasing the flow rate of carbon dioxide gas to the inlet air from 1:20 to 1:15, the amount of absorption speed increased due to the increase of the driving force of this gas in the gas phase, and also by increasing the flow rate of carbon dioxide gas to the inlet air from 1: 15 to 1:10 The amount of absorption speed decreases due to the reduction of the absorption capacity as well as the increase in the gas remaining in the air stream. For nickel oxide nanoparticles as well as carbon nanotubes, it can be observed that for the case of using a mixture of nickel oxide nanoparticles (25%) and carbon nanotubes (75%) in the presence of CTAB surfactant, the maximum absorption efficiency and mass transfer molar flux Carbon dioxide gas is more than other forms, the main reason can be attributed to the nature of carbon nanotubes as well as nickel oxide nanoparticles. The results also showed that nickel oxide nanoparticles act as agitators which in microscopic dimensions cause the displacement of carbon nanotubes and due to their brown catheter movements cause micron vortices which increase the mass transfer at the surface of liquefied gas. Also, the amount of molar flux and carbon dioxide adsorption efficiency decreases with increasing nanoparticle concentration from a maximum of 5% by mass, the main reason for this decrease can be attributed to the increase in nanofluid viscosity, which increases significantly with increasing nanoparticle concentration.

Soft tissue substitutes are subjected to large deformation in vivo, so the matching of deformation behavior between substitute and tissue is a complex but important criterion for soft tissue repair. Hernia repair mesh is a typical soft tissue substitute, and the mismatch of mechanical properties between mesh and tissues normally leads to decline in the quality of life and hernia recurrence. Therefore, before clinical applications, the evaluation for the mechanical biocompatibility of mesh is particularly important. Currently, several methods have been developed to evaluate mechanical biocompatibility of soft tissue substitutes, including physicomechanical testing, non-invasive measurement, and numerical modeling, etc. However, a comprehensive summary is lacking to provide reference for the selection, implementation and optimization of these methods. In this paper, taking the hernia repair mesh as an example, we systematically review these methods from following aspects: (1) proposing critical issues that need to be paid attention to when performing physicomechanical testing on substitutes, (2) systematically analyzing characteristics and applicable sample types for several typical physicomechanical testing techniques, (3) comprehensively summarizing the advantages and limitations of the main non-invasive measurement methods, and showing the potentials of these methods, (4) emphasizing and dissecting the merits of numerical modeling compared with physicomechanical testing and non-invasive measurement, and proposing the existing and potential improvements of this method. Furthermore, the application scope and future development direction of these methods are proposed. This paper might play an important role in guiding the selection and improvement of evaluation methods for mechanical biocompatibility of soft tissue substitutes.

Hexafluorosilicic acid (H2SiF6) is one of the most harmful by-products of the agricultural industry and because of the enormous scale of the industry, disposal of the acid on such a large scale is a huge concern. H2SiF6 has adverse effects on both human physiology and the environment. Moreover, the acid is also corrosive to many common materials such as glass and metals. The method outlined in this paper aims to dispose of this corrosive and harmful by-product of the agricultural industry while also producing a very valuable product in the form of mesoporous silica nanoparticles (MSN's). Previous efforts to produce MSN's in bulk fell short as they were not sustainable, cyclic and/or required complex equipment. The current method aims at ammoniation of H2SiF6 with certain controllable parameters in order to obtain pure MSN's. The parameters used were rate of addition of ammonia and the rate of agitation post ammoniation. EDX and XRD confirmed that the synthesized particles were MSN's. Dynamic light scattering (DLS) of the various samples showed a good size distribution and confirmed that, by changing process parameters, we were able to control the particle size. BET confirmed a high surface area and an average pore size was also obtained. MSN's can be used for a variety of purposes, including formation of aerogels, bio-sensing, and particularly in targeted drug delivery where the properties of MSN's make it a very viable candidate. The process presented in this paper can be extended to make it a cyclic and sustainable process capable of producing two nanomaterials.

A three-dimensional (3D) cellular automaton model describing the austenite grain growth process of Fe-1C-1.5Cr alloy steel is established. This model proposes a discrete representation of the three-dimensional grain boundary curvature, and calculates the 26 neighbor lattice points to the center lattice point in three-dimensional space. The strength of neighbor lattice point’s influence is determined by the distance from the center lattice point. The paper presents the calculation steps of the three-dimensional cellular automaton model and the calculation methods of key parameters such as grain boundary curvature and grain growth speed, and validates the model calculation results. The results show that the model established in this paper can well describe the austenite grain growth process of Fe-1C-1.5Cr alloy steel at different temperatures. The model can be used to study the grain growth process of Fe-1C-1.5Cr alloy steel under three-dimensional conditions. Keywords: Three-dimensional cellular automaton model, Three-dimensional boundary curvature, Austenite grain growth

In order to model the progressive failure of laminates under tensile load, the finite element model adopting the floating node method combined with In-Situ effect strength theory is developed in this paper. The floating node method is based on the original finite elements to assign more additional degree of freedoms on the edges or nodes. In this way, it can realize crack propagation explicitly and prevent the singularity caused by the integration of body elements at the damage points. The calculation method of In-Situ strength theory based on the assumption of fracture mechanics is introduced and deduced, which improves the accuracy of the failure strength prediction. Two kinds of notched composite laminates’ tensile experiments were carried out. Experiment results show that different ply sequences ([453/903/-453/03]s and [45/0/-45/90]3s) have different failure strength and failure progress. In this paper, the reliability of the model is verified by comparing the experimental results with the simulation results. The comparison results demonstrate that this model can realize the explicit crack propagation and predict the failure strength precisely. In addition, this model can represent some failure modes such as fiber breakage, matrix damage, and delamination, which were observed from experimental phenomenon. The traditional failure criteria compared to the improved criteria's accuracy is significantly improved. It demonstrated that the analysis in considering the In-Situ effect is very necessary. Keywords: In-Situ theory, Floating node method, Notched laminates

With the increasing demand for light weight design in industries such as aerospace and automotive, sheet metallic materials with high strength and low density have been intensively manufactured and widely applied. However, plastic deformation induced surface roughening is an undesirable and a practically unavoidable phenomenon for sheet metallic materials and becomes the subject of great attention in recent years. The evolution of surface roughening plays important roles in the strain limit of the deformation and also significantly influences the product quality and application. This paper provides a comprehensive overview of both experimental and numerical modelling contributions to understand the surface roughening behaviour of sheet metallic materials during various plastic deformation and manufacturing processes. It has been found that roughening of the free surface or necking of the interface is induced by grain scale strain heterogeneity and strongly dependent on the strain the material experienced, strain state and direction, grain size and texture, lubrication, mechanical properties of materials, rolling parameters, etc. By controlling and optimising these parameters, the surface roughening can be optimised for different materials and processing techniques to suit different applications.

Lateral friction surfacing, a solid-state deposition process, is a novel friction surfacing technique. In this approach, frictional heat and plastic deformation result in deposition of consumable material from the radial surface of a tool onto a substrate. This paper presents a comprehensive assessment of lateral friction surfacing of AA2011, AA6061, and AA7075 aluminum alloys, with particular focus on the impacts of process parameters on the coating properties. The influence of process variables such as tool rotational speeds, normal applied forces, and type of consumable materials was investigated on the process temperature, physical, and metallurgical characteristics of the deposits using optical microscopy, infrared thermography, scanning electron microscopy, and EDS. This study exhibits that the lateral friction surfacing approach enables the deposition of ultra-thin and smooth layers of different aluminum alloys. Furthermore, the temperature generated in this technique was low enough to avoid plasticizing the substrate and intermixing between the consumable material and substrate, which mitigates the thermal impacts on the grain structures and metallurgical characteristics. The lateral friction surfacing performance of the different alloys can be partially explained by their material properties. High input energy provided by high normal forces and tool rotational speeds may result in failure in the deposition process of materials with lower thermal conductivity and melting point, which emphasizes on limitations for the process parameters during the process.

Solar energy is the leading thermal source from the sun, with huge use of technology such as photovoltaic cells, solar power plates, photovoltaic lighting, and solar pumping water. The current effort deals with solar energy analysis and a technique to enhance solar aircraft effectiveness by using solar and nanotechnological energy. The work is based on the investigation of thermal transfer by utilizing hybrid nanofluid past an inside solar wings parabolic trough solar collector (PTSC) to rich the studies of the solar aircraft wings. The thermal source is titled solar radiative flow. For various properties such as porous media, Cattaneo Christov heat flux, viscous dissipation, play heating and thermal energy flow, the heat transfer efficiency of the wings is verified. In the case of the tangent hyperbolic fluid, the entropy generation analysis was applied. The modeled energy and momentum equations were managed using the well-established numerical plan known as the Keller box process. This paper is made up of double-different kinds of nano solid particles, Cu (copper) and ZrO2 (zirconium dioxide) in EG (ethylene glycol) as standard fluid. Various control parameters are discussed and shown in figures and tables for velocity, shear stress, temperature outlines, frictional factor, and Nusselt number. The efficiency in the aircraft wings in the case of thermal radiation amplification and variable thermal conduction parameters is seen to be improved in terms of thermal transfer. In comparison to the traditional nanofluid, hybrid nanofluid is the ideal source of heat transfer. The thermal efficiency of ZrO2–Cu/EG compared to Cu-EG decreases to a low of 2.6% and peaks to 3.6%.

In this paper, flower-like ZnO (FZnO) particles were synthesized through a facile method using different precursor content and reaction time. The as-prepared ZnO particles were then characterized by scanning electron microscopy (SEM), and the results showed the production of particles with varied aspect ratios (5–14). Composites of poly (vinylidene fluoride) (PVDF) with FZnO were prepared and also studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier-transform infrared (FTIR). A slight reduction of thermal properties was noticed, where the degradation temperature decreased from 439 °C for neat PVDF to around 431–438 °C for the PVDF composites with FZnO. Besides, an increase of β-crystals was observed by incorporating these particles, shifting from 31% (neat PVDF) to 37% in the composites. Furthermore, the permeability coefficient to CO2 reduced around 13%, indicated that the composites with the obtained flower-like ZnO particles might have potential applications as a barrier layer in oil ducts pipelines compared with neat PVDF.

Nanoparticles (NPs) as a nanotechnologies unit have a huge potential for improving drilling fluids. However, the role of NPs in this field is still in its infancy and consequently has attracted much more attention in the last years. This review is going to investigate the drilling fluids modified by nanoparticles. Moreover, effects of various nanoparticles include polymeric, ceramic, metal and carbon-based NPs on drilling fluid and technical and economic benefits of them will be inspected. Although various reviews of nano-based drilling fluids have been reported, few papers have provided a comprehensive review and development of nanoparticles application in this issue. This review summarizes the recent research advances in the synthesis and applications of NPs in drilling fluids system. The roles of NPs in rheology and fluid loss control, mud cake thickness, filtration properties, and thermal properties are discussed. Accordingly, various literature reviews demonstrated that use of nano materials in drilling fluid has two main goals: improvement of thermal and physical-mechanical of drilling fluids. The studies in this issue will facilitate the design of advanced functional nano-composites for drilling fluids.

In this paper, the preparation of SrAl2O4:Eu2+, Dy3+ (SAOED) phosphors coated with SiO2 and poly (methyl methacrylate-co-butyl acrylate) [P(MMA-BA)] was reported, the water resistance and afterglow performance of SAOED phosphors coated with different layers were compared. The photoluminescence behavior and dispersion stability of coated SAOED phosphor as a pigment used in waterborne UV acrylic coating (WUV) were also evaluated. The scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR) analysis results showed continuous and uniform SiO2 and P(MMA-BA) layers on the coated phosphors, respectively. Based on X-Ray Diffraction and Excitation and emission spectra, the coating process did not cause damage to the phosphor crystal. The pH value of water solution versus time showed that the phosphors can obtain excellent water resistance with a 5wt.% SiO2 coating. Fluorescence performance test showed that when the mass fraction of coated phosphor in the WUV was 15%, and the light excitation time was beyond 180s, the afterglow performance of the WUV was the best with the excitation brightness exceeding 120 Lux. The dispersibility test results showed that the SiO2–P(MMA-BA) hybrid coating layer could maintain the uniform dispersion stability of SAOED phosphor in WUV for more than 72 h.

A precise springback prediction is of great significance to reduce the manufacturing time and also to improve the forming quality for frame-rib parts. Based on Sobol and improved grey relation analysis, a novel prediction algorithm for springback of frame-rib parts in rubber forming process is proposed in this paper. First of all, the mapping model between springback angle and geometric parameters of the flange is established by using the response surface method and experiment. With the obtained mapping model, the weight of each parameter on springback is calculated by Sobol global sensitivity analysis method. Afterwards, a novel method for springback prediction is presented by incorporating k nearest-neighbor within improved grey relation analysis. A case study on springback angle prediction for the flange of rib part is given to validate the applicability and effectiveness of the proposed approach. Furthermore, by comparing the predicted values with the actual value of 18 cases, the high accuracy and stability of the proposed algorithm are further demonstrated.

The damage evolution process in 316 austenitic stainless steel at the plastic stage were investigated in this paper by using the in-situ EBSD technique and MD simulation in combination. The damage mechanisms of 316 steel are typified by an intergranular and intragranular mixed mode. The in-situ EBSD results showed that the intergranular damage was the defects formation at the GBs, and the twin-GB intersections and the triple GB are the preferred damage sites. While the intragranular damage was manifested by the mixing of lattice orientation change, intragranular flaws appearance, and twin degradation; The MD simulation results manifested that the initial lattice structure changed after the plastic strain, and the continues increase of the atom displacement resulted in the defect formation. The simulation results also verified that the twin-GB intersection site could be a fragile location, the void preferentially appeared here, and the disorder degree of atoms over here were great. In addition, the defects also generated at the triple GB, which indicated that the triple GB could also be a weak location.

The existing cross arms in high transmission towers are made of pultruded glass fibre reinforced polymer composite (PGFRPC). The moisture, temperature change in the atmosphere, and other environmental factors affect the performance of these members and cause a complete failure. It is apparent that any material used in such applications is susceptible to attack from environmental factors. Therefore, a feasible solution for this issue is to enhance the PGFRPC with a composite-filled sandwich structure as an alternative that could sustain longer than the existing cross arms due to its superior performance under bending and compressive loads. This paper presents a case study on experimental and analytical mechanical performance of both PGFRPCs and composite-filled sandwich structure. In this review, the composite-filled sandwich structure is proposed as an alternative to the conventional PGFRPC.

Ultrasonic surface rolling technology is a new mechanical surface treatment technology that can improve the surface integrity, increase the amplitude and depth of the residual compressive stress layer and improve the fatigue property of metal materials. In this paper, the effect of ultrasonic rolling on the surface layer's microstructure and properties of Ti6Al4V alloys is investigated. The microstructure, surface roughness, surface topography, microhardness and residual stress were used to characterise the surface-modified layer. Specimens treated by ultrasonic surface rolling obtained the smallest surface roughness (0.231 μm) and largest plastic deformation depth (304.38 μm), simultaneously, under sixteen processing stage numbers. The rule of surface compressive residual stress distribution had a similar tendency to the law of surface microhardness distribution. Furthermore, the grain size of the strengthened surface layer decreased, the texture type changed and the Schmidt factor increased compared with the matrix. The increase of microhardness and residual stress is due to grain refinement and dislocation strengthening.

In the initial stage, as well as today, physical models are frequently applied for basic oxygen furnace (BOF) process development. BOF cold model simulations have as fundament the geometric, kinematic, and dynamic similarity. The dimensionless numbers warranty the similarity. Based on the similarity criteria, it is possible to transpose the laboratory results for the industry. Develop the right methodology to get precise measurements of proposed experiments is a critical step in cold modeling. Due to different characteristics available regarding cold modeling, the work summarized in this paper offer a literature review centered in measurements methodologies for BOF cold modeling and describes the methodologies developed at Processes Simulation Laboratory (LaSiP) to measure and define mixing time, mass transfer, jet penetration, decarburization area, slopping and projection rate on cold models.

Vanadium pentoxide (V2O5) is one of the fundamental materials applied in the productions of batteries, vanadium-aluminium alloys, biomedicine, catalysis, etc. High purity V2O5 can be prepared from an intermediate product, namely ammonium polyvanadate (APV), using roasting after a drying process. In this paper, microwave heating was used as an alternative drying option for APV, which has advantages including selective heating, high heating efficiency, energy-saving, and environmental protection. The authors investigated the microwave heating characteristics of APV and discussed the effects of microwave power, the mass of APV, and initial water content on the efficiency of microwave drying. The dynamic analysis of the APV microwave drying process was also carried out. Four groups of thin-layer drying dynamic models, namely Modified-Page model, Verma model, Sickmplified-Fick's-diffusion model, and Two-term-exponential model, were fitted with the experimental data. Through comparison, the Modified Page model could better describe the microwave drying process of APV.

In this paper, the structural, morphological, linear & non-linear optical, and magnetic properties of spray pyrolysis nanostructured Sn1-xCoxO2 thin films (0 ≤ x ≤ 0.08) were studied employing X-ray diffraction (XRD), atomic force microscope (AFM), spectrophotometric, and vibrating sample magnetometer (VSM) techniques, respectively. A tetragonal type structure was observed for films without any sign of impurities. XRD with Rietveld refinement analysis further revealed an increase in lattice parameters and unsystematic changes in crystallite size. AFM micrograph analysis shows that the surface roughness and root mean square roughness of the film are improved with increasing Co doping. Moreover, the spectrophotometry results indicate a direct optical transition for the film with an energy band gap reduces from 3.8 eV (x = 0) to 3.34 eV (x = 0.07) due to the rise in structural disorder and the increase in the density of localized states. The optical constants are calculated from the light transmission spectrum using the envelope method of Swanepoel. It is seen that the overall behavior of the refractive index n(λ) and extinction coefficient k(λ) increase with increasing of Co content. The dispersive oscillator parameters estimated from the single-oscillator Wemple–DiDomenico model were used to determine the non-linear optical parameters, such as the third-order non-linear optical susceptibility χ(3) and non-linear refractive index n2. Finally, intrinsic room temperature ferromagnetism is observed, which is interpreted based on the bound magnetic polarons model. In conclusion, Co doping in SnO2 host semiconductor nanocrystalline films enhances their optical and magnetic characteristics, making it a potential candidate for multifunctional applications like optoelectronics and spintronics devices.

Based on Marc. MSC software, this paper developed a thermo-elastic-plastic finite element method (FEM) to simulate the welding residual stresses and deformation in the low alloy high strength steel joints. The welding residual stresses and deformation in the Q345 Steel H-section butt-welded joints were calculated using this method. An H-section butt-welded joint was fabricated and the welding residual stresses were measured. Based on the simulation and experiment, the influence of welding sequence on the residual stress distribution and deformation in the Q345 steel H-section butt-welded joint was investigated. The results indicate that the welding sequence has a relatively small effect on the residual stress distribution in the flanges of the H-section joints, but a significant influence on that in the web. Under three different welding sequences, the welding deformations in the joints were similar. In the view of controlling welding residual stress, welding the web first is recommended in the fabrication of the H-section butt-welded joint.

Sintering mechanisms of copper nanoparticles on copper plates are investigated based on molecular dynamics (MD) simulation. In this paper, the roles of tilt grain boundaries (GBs) and Σ5 twisted GBs on sintering kinetics are considered. Regardless of the diameter of the nanoparticle sphere, it is observed that stacking faults and dislocations are formed near the GBs by crystal analysis at the early stage of sintering and throughout the entire sintering process. The stacking faults are overflowed to the surface during the constant temperature stage. The tilt GBs disappears rapidly at the initial stage of sintering, while the Σ5 GBs is instantly eliminated in the middle temperature region of sintering by the rigid rotation of the nanoparticle sphere. Moreover, besides the contribution of atom diffusion in sintering neck growth, misalignment between the two particles brings about enhanced GBs diffusion. These observations provide insights into the tailored high-angle GBs applicable to nano-scale sphere-plate samples.

Repairing and replacing of tumor tissues have been grown due to the genetic changes and environmental factors. Conventional cancer therapies apply the systemic approaches for delivery of anticancer agents in which normal and cancer cells are not discriminated. Therefore, the risk of cancer recurrence in the resection site increases. In this paper, we studied a graphene reinforced gelatin hydrogel for tissue engineering and local controlled release of chemotherapeutic agents. Protein-integrated graphene (PIG) synthesized by ultrasonic-supported technique was incorporated into gelatin matrix, where the swelling ratio of hydrogels decreased with increasing the PIG concentration. In hydrogels, doxorubicin (DOX) was released in a controlled and pH-sensitive manner and the release rate was controlled by PIG concentration. The effect of PIG on the controlled release system was detected in MCF-7 cell viability. Moreover, 3D tumor spheroid test studied the extracellular matrix (ECM) and cell aggregation as an in vivo model. Generally, we introduced a novel hydrogel nanocomposite, which is a suitable candidate for post-surgery treatment and localized therapy.

The spatter behavior in the laser powder bed fusion (L-PBF) additive manufacturing is unavoidable owing to the interaction between high-energy laser beam and powder particles. And the droplet spatters generated by the laser induction not only directly reflect the steady-state of the micro-molten pool but also directly affect the processing quality of the L-PBF process. In order to further understand the mechanism of laser–powder interaction, and the generation and evolution of droplet spatter, the paper presents a droplet spatter feature information extraction algorithm and a manufacturing status classification method. Three kinds of feature information of droplet spatter were collected, extracted, and discussed by high-speed imaging, image processing, and statistical analysis techniques. The evolution mechanisms of the molten pool, the keyhole, and the droplet spatter behavior under different linear energy density inputs were discussed in combination with the single-track build. A mapping model of the droplet spatter behavior characteristics and manufacturing status was processed after that. The accuracy and reliability of the mapping model were verified and analyzed by using the AdaBoost CART classification model. The classification model not only verified the mapping mechanism, and the findings provide a basis and reference for the quality control of the L-PBF process in the future.

In the gas metal arc welding (GMAW) process, the intense arc light and high temperature conditions bring great difficulties to the online identification of welded joint penetration. At present, visual sensing method and arc sound detection method are mainly used to identify the welded joint penetration, there are few reports about using welding temperature field to identify welded joint penetration. In this paper, a method of using infrared thermal imaging to identify the welded joint penetration was proposed, a single infrared thermal imager was used to monitor the welding temperature field in real time, the solidified weld area outside the weld pool area was selected as the region of interest (ROI) for real-time temperature measurement. The temperature field distribution features of ROI were extracted, taking these features as input and welded joint penetration as output, the identification model for welded joint penetration was established based on artificial neural network (ANN). The identification accuracy and generalization ability of the identification model were verified by a variety of butt welding experiments, the experimental results show that the identification accuracy of the established model for three penetration states of welded joint is higher than 96%, which can be applied in the online identification of welded joint penetration.

Gas hydrates are ice-like compounds that can affect the flow assurance in oil and gas pipelines due to their structural characteristics. Alginate is a polysaccharide naturally derived from the brown seaweed Phaeophyceae and is produced as an extracellular material by bacteria, such as Pseudomonas and Azotobacter. The novelty of using alginate as a natural gas hydrate inhibitor was investigated in this paper. To predict the amount of methane hydrates that formed over time, a modified Johnson−Mehl−Avrami−Kolmogorov model (JMAK) was applied. It is noted that for the studied polymer, lower concentrations of 0.1% (wt./vol) showed better inhibitory potential, and acidic pH was favorable to this behavior. The system that behaved best against methane gas hydrate inhibition was 0.1% (wt./vol) pH 4. Alginate showed a good inhibitory capacity. The JMAK model was found to be suitable for describing the crystallization kinetics of the studied systems. The kinetic parameters were calculated for this model. This study describes a new way to explore the potential of alginate as a kinetic inhibitor by delaying the formation of hydrates.

The effects of applied load, sliding speed & temperature on the wear behavior of pure M50 alloy steel (M sample) and M50 reinforced with 10 wt.% Al2O3 (MA sample) & M50 hybrid reinforced with Al2O3 and graphene (MAG sample) were studied. The powders were mechanically mixed and sintered by spark plasma sintering (SPS) technique under Argon atmosphere at 1000 °C for 5 min under 35 MPa pressure. The sample surfaces were mechanically prepared to study the wear & friction behaviors via applying mechanical polishing using 0.05 μm diamond pastes and 1200 grit emery papers to enhance the surface roughness. The phase structure and microstructure were estimated using XRD, Electron Probe Micro-Analysis (EPMA, JAX-8230) and Energy Dispersive Spectroscopy (EDS, GENESIS 7000). The hardness and density of all samples were investigated according to HVS-1000 Vickers' hardness test and Archimedes’ principles, respectively. Friction and wear tests were carried on a high-temperature pin-on-disk tribometer (HT-1000). The investigated samples were cut into disk-shaped specimens with 8 mm thickness and 25 mm diameter. Then, the prepared specimens were sliding against silicon nitride (Si3N4) balls. The samples were exposed to four different loads (2, 5, 8, and 11 N). Also, four different sliding speeds (0.18, 0.36, 0.54, and 0.72 m/s) was performed at room temperature (RT). Another group of samples were tested at constant applied load of 11 N and constant sliding speed of 0.72 m/s for four different temperatures (RT, 150, 300, and 450 °C). MAG exhibited enhanced tribological properties compared with M and MA thanks to the synergic action between Al2O3 and graphene as well as the creation of iron oxides, aluminum dioxide, chromium oxide, molybdate, and silicon oxide on the formed tribo-film.

In the present paper we report proof of consistent non monotonic lattice variation (NMLV) as a function of grain size in nanocrystalline CeO2. By analyzing more than 30 powder samples of CeO2 with grain size ranging from 5 to 200 nm which were synthesized by three different methods, it was found that in the nanocrystalline powders the unit cell parameters are smoothly varying along the decreasing of grain size with moderate contraction between 100 to 30 nm and severe expansion when the grain size become smaller than 20 nm. As a result of these two opposite trends a minimum value of unit cell parameter was detected in grain size between 25 to 50 nm. The lattice parameter change can be modeled as two global effects acting simultaneously. The first one is a contraction due to surface tension and the second one is a lattice expansion caused by ionic bonds weakening as the grain size decreases. This model can be applied to most ionic nanocrystalline materials. Consequently, it is recommended to add a new category “ambient-nano” in the crystallographic and diffraction data bases for nanomaterials with structures controlled by grain size.

Silicon purification with Al–Si solvent refining is a potential method to obtain solar grade silicon (SoG-Si). Hydrogen is a helpful element to enhance the removal of impurity boron during the Al–Si solvent refining. However, the interaction mechanism between hydrogen and boron is not very clear. In this paper, the ab initio calculation method, which is based on the density functional theory (DFT), was adopted to further understand the interaction behavior of hydrogen and boron. The structure properties, bonding energy, energy band structure and density of states (DOS) of BH2, BH3, B2H6, SiH4 and AlH3 were calculated and analyzed using the CASTEP module in Materials Studio. The results show that BH2 has the feature of semiconductor, while BH3, B2H6, SiH4 and AlH3 belong to insulator. Additionally, the order of binding energy for hydrides from large to small is B2H6, BH3, SiH4, BH2 and AlH3, indicating that B2H6 is the most stable compounds among the hydrides. The DOS and partial density of states (PDOS) analysis show that the valence band of B2H6 contains four parts, which are contributed by H-1s and B-2s states, H-1s, B-2s and B-2p states, H-1s and B-2p states, H-1s and B-2p states, respectively. To verify the calculation results, an experiment and a thermodynamic analysis were carried out, and both of them proved that the calculation results agree well with the experimental results.

Aluminium alloys are one of the choice materials with ever-increasing demands in manufacturing industries. The aluminium alloy 6 xx series such as AA6061-T6, has emerged as one of the promising materials utilized owing to its combination of favourable properties which include high strength to weight ratio, good ductility, excellent corrosion resistance and relatively low cost. These superior properties are responsible for its emergence and usage in the fabrication of aircraft wings and fuselages, yacht/ship construction, automotive rims and wheel spacers. However, joining of AA6061-T6 including the use of friction stir welding (FSW) has serious concerns because the mechanical and tribological properties of the AA6061-T6 welded joints deteriorate significantly compared with the base metal. This phenomenon has been attributed to the severe softening encountered at the stir zone (SZ) of the aluminium matrix during FSW. Other inherent challenges of FSW such as weld thinning, kissing bond and keyhole formation also contribute to the reduction in the weld joint quality. The softening phenomenon has been linked to the dissolution of the strengthening precipitates (B″-Mg5Si6) as a result of high heat input during the welding process. Hence, this paper attempts to review the various improvement strategies adopted in the existing studies to improve the quality of AA 6061-T6 welded joint. These include parametric optimization, selection of appropriate tool design, pre and post heat treatments, adoption of different groove/hole designs for particle addition as well as the addition of reinforcement particles to the weld joint. The variants of FSW recently developed will also be considered. The findings from the review will generally be useful for future work on FSW of heat treated aluminium alloys. The evolution of FSW and its associated challenges are briefly discussed while the research areas yet to be harnessed are suggested for future works.

Accumulative roll bonding (ARB) is a severe plastic deformation (SPD) technique that has been extensively used in a wide range of metals to improve their mechanical properties. In particular, ARB processed materials display an increase in both yield and ultimate tensile strength, since the SPD processing induces a remarkable grain refinement. In precipitation-hardened alloys, such as aluminum 7075, this leads to a synergistic effect which further enhances strength. Although the reported results are promising for high-strength applications, thermal stability of the microstructure after processing remains an open question. In this paper, we present an investigation of the thermal stability of the texture, microstructure, and mechanical properties of Al-7075 samples processed by ARB to an equivalent Von Mises strain of 240%. After processing, yield and tensile strength displayed improvements of 30% and 20% respectively over the T6 condition. Crystallographic texture was found to depart from the rotated cube component to Dillamore/Taylor and Goss components. Several annealing heat treatments ranging from 373 to 673 K (100–400 °C) were carried out and it was found that the improved mechanical properties are stable up to 423 K (150 °C). The texture was found to slowly revert to a rotated cube with increasing temperature. The results are discussed in terms of the combination of strength and formability as calculated by the Lankford parameter using the visco-plastic self-consistent code (VPSC).

Crumb rubber has been used since sometime to improve the impact and toughness of normally brittle concrete. As the failure due to fatigue and impact loadings is a problem in normal concrete; the flexibility of the rubber aggregates could be the key to solve it. Even though there is a marginal reduction in the mechanical properties of crumb rubber concrete, this can be overcome by appropriate treatment of the crumb rubber aggregates. Methods, such as mechanical, chemical, thermal and microwave treatment could be used to treat crumb rubber aggregates to enhance their adhesion with the cement mortar. This is desirable since a significant positive impact on the environment could be achieved by utilizing crumb rubber from scrap tires in concrete resulting in the solution of their disposal problems and conserving the depleting sources of natural aggregates. Even though some literature on the properties of crumb rubber concrete is available, there is a need to evaluate methods to overcome the deficiencies of crumb rubber concrete. This paper is a state-of-the-art review on the mechanical, durability, thermal, and acoustic properties of concrete incorporating untreated- and treated-crumb rubber. The beneficial treatment methods have been categorized. It is hoped that this review will encourage the use of crumb rubber concrete in the construction of infrastructure and form a basis for further research on this material. The use of crumb rubber concrete will lead to a sustainable utilization of a waste material, leading to environmental protection and conservation of depleting sources of natural aggregates.

This paper presents an organic memristive device based on the soft and quasi-liquid trypsin biomaterial. Accordingly, trypsin is isolated from the bovine pancreas and deposited on a conducting fluorine-doped tin oxide (FTO) substrate. The current–voltage (I–V) measurements of the trypsin/FTO device show a hysteresis loop at multiple frequencies and voltages. The results demonstrate that the current and resistance of the device can be modulated by altering the frequency and magnitude of the applied signal, suggesting the feasibility of this material for brain-inspired computing devices. The hysteresis area of the device increases in proportion to the frequency of the signal, signifying the inverse-memristive phenomenon. The time-domain flux, time-domain charge, and charge-flux properties are calculated from the experimental I–V data to demonstrate the memristive nature of the trypsin hydrogel. Interestingly, the trypsin hydrogel memristive device mimics bio-synaptic properties such as potentiation–depression and four complex spike-time-dependent plasticity learning rules. Electrochemical studies are performed to understand the electrochemical kinetics of the device. A possible switching mechanism is illustrated to show the memristive effect of the trypsin hydrogel. The results of the present investigation suggest that trypsin can be a possible biomaterial to develop an electronic synaptic device for neuromorphic computing applications.

The microencapsulation of volatile phase change materials is an important and challenging area for low-temperature thermal energy storage. Our previous studies have effectively addressed the challenge of long-term volatile core retention and also indicated that the quality of the obtained poly(urea-formaldehyde) microcapsules is highly affected by various process parameters, including reaction temperature, initial pH, reaction time, and homogenization speed. In this paper, the Taguchi orthogonal array has been employed to optimise controllable process parameters to identify the most synergistic combination, in order to maximise the payload, yield, and encapsulation efficiency. The Taguchi signal-to-noise ratio results substantiated that the most efficient combination of parameters was 3 h reaction time, pH 3.5, 55 °C reaction temperature, and 1200 rpm homogenization speed. With this combination of parameters, microcapsules with superbly high payload of 95.2%, as well as a yield of 30.5% and encapsulation efficiency of 71.1% were amalgamated. In addition, Analysis of Variance (ANOVA) was also utilised to demonstrate the mean response magnitudes (% contribution) of each of the four controllable process parameters, in terms of contribution for the payload, yield, and encapsulation efficiency. Overall, it was indicated that the temperature is the most influential parameter at 83.1% contribution, followed by pH at 6.8%, reaction time at 5.2%, and homogenization speed at 4.9%. Such findings in this work postulate the fundamental insights into maximising the output of the formulation conditions, which in turn is aimed to minimise the time and cost of production of the microcapsules.

This paper presents an alternative approach in powder injection moulding (PIM) process by highlighting the advantages of using irregular-shaped and bimodal size powder in Ti6Al4V-HA composite. An investigation on the rheological behaviour Ti6Al4V-HA feedstock at a ratio of 90:10 weight percent was done using spherical and irregular shapes of Ti6Al4V powder particle, together with palm stearin and polyethylene acts as a binder system. Subsequent to the rheological results, the critical powder volume percentage (CPVP) value of the bimodal feedstock improved by 5–8 vol. %. Furthermore, an irregular-shaped Ti6Al4V-HA shows pseudoplastic behaviour and low viscosity with the values of 73–408 Pa.s which is comparable with the spherical-shaped Ti6Al4V-HA (48–305 Pa.s). The injected parts of bimodal irregular-shaped Ti6Al4V-HA also successfully produced without any cracks and distortion with high relative density of 95% after sintering. The result is supported by SEM morphological images which displays micron size porosities that will benefit the sintered part as scaffold for a good osseointegration property with cells. The findings highlight the suitability of irregular-shaped Ti6Al4V-HA during injection moulding as it had outstanding rheological behaviour as good as spherical-shaped Ti6Al4V-HA. Sintered irregular-shaped Ti6Al4V-HA with porous morphological structure, suggest a useful alternative material of irregular morphology of Ti alloy in biomedical industries especially for bone implant application.

This paper presents the results of an experimental investigation of the behaviour and strength of hybrid kenaf/glass fibre-reinforced epoxy tubes subjected to axial intermediate-velocity impact loading. The specimens under axial intermediate-velocity impact involve three filament winding orientation parameters of ±30°, ±45° and ±70° of hybrid kenaf/glass fibre-reinforced epoxy and glass fibre reinforced-epoxy. All materials and sampling were prepared at SIRIM STV Malaysia laboratory by using automated filament winding machine to obtain a proper intraply hybrid kenaf/glass composite tube fabricating procedure. Results from the study showed that the concept in fabricating intraply hybrid filament winding technique of natural/synthetic materials has performed similar physical crashworthiness of synthetic composite tube with various progressive crushing behaviours. It was also observed that the winding orientation parameter at θ = 30°, 45° and 70° of the hybrid composite tube have increased the energy absorber properties with 33%, 34% and 56% respectively, compared to the GFRP.

This paper presents the effect of nano-CaCO3 (NC) on the compressive strengths and durability properties of high volume slag (HVS) and high volume slag-fly ash (HVS-FA) blended concretes. The study examined the improvement in early and later age compressive strengths and durability properties such as sorptivity, volume of permeable voids, rapid chloride penetration and drying shrinkage of HVS concrete containing 69% blast furnace slag (BFS) and HVS-FA concrete containing combined BFS and fly ash (FA) content of 69% due to the addition of 1% NC. Results show that the addition of 1% NC improved the compressive strengths of HVS and HVS-FA concretes significantly by 43% and 28%, respectively at 3 days compared to the control HVS and HVS-FA concretes without NC and exceeded the compressive strengths of control OPC concrete at later ages. It is also found that 1% NC inclusion reduced the water sorptivity of HVS and HVS-FA concretes reasonably after 28 days of curing and reduction is greater after 90 days of curing exhibited comparable water sorptivity to OPC concrete. Significant improvement is also observed in reducing the volume of permeable voids and controlling the drying shrinkage strain at early age as well as later ages of both HVS and HVS-FA concretes due to 1% NC inclusion. Outstanding resistance against chloride ion penetration is also observed in HVS and HVS-FA concretes due to addition of 1% NC to the very low level of chloride ion penetration according to ASTM standard. SEM and EDS analysis revealed a denser microstructure of paste and interfacial transition zone (ITZ) around aggregates.

Geopolymer is emerging as a potential alternative material to the ordinary Portland cement (OPC) owing to its energy efficiency and environmental protection. However, the effect of the mix design parameters on the behavior of geopolymer concrete (GPC) produced using local metakaolin (MK) is not well established. This paper presents findings from a comprehensive experimental program to study the effect of various mix design parameters on the properties of fresh and hardened MK-based GPC. Seventeen mixes were cast in four groups to investigate the effect of four parameters, including sodium silicate to sodium hydroxide ratio, alkaline solids to MK ratio, aggregate content, and water to solids ratio on the properties of GPC. The investigated properties included workability, density (wet and dry), development of compressive strength with age, splitting tensile strength, ultrasonic pulse velocity, water absorption, and horizontal abrasion resistance. Besides, two reference OPC concrete mixes, equivalent to two MK-based geopolymer mixes, were tested for the sake of comparison. The test results were helpful in developing a better understanding of the behavior of MK-based GPC. Some useful models are proposed for predicting workability, splitting tensile strength, water absorption, and weight loss in abrasion for MK-based GPC. The test results were supplemented and confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) analysis performed on some selected GPC mixes.

The era of the Internet of Things (IoT) is becoming a reality, and the display equipment is at its center. The display device is the window that connects the IoT and humans, and is evolving into various form factors convenient to human use, such as foldable mobile phone, flexible wearable device, paper-like display, and rollable TV. Even though transparent flexible electrodes and substrates have been developed, their assembly remains a challenge. Therefore, the importance of optically clear acrylic pressure-sensitive adhesives (PSAs) that ensure device integrity by easily stretched and mitigating the stress during repeated stretching and bending process is being emphasized. In this study, elongation and recovery features were identifiable as key flexible properties of PSAs. These properties were estimated by measuring shear strain and strain recovery using a universal testing machine and by dynamic mechanical analytics respectively. Compared to conventional UV metal halide curing, a newly introduced ultraviolet light-emitting diode (UV LED) curing process resulted in different PSA property variables, namely UV exposure intensity and UV exposure time. Fully cured acrylic PSA realized under UV LED exposure level 30 for 8 s demonstrated the highest shear strain with excellent strain recovery of ~23,500% and 94% respectively. Under these conditions, effective material adhesion performance was achieved while retaining optical transparency and thus fulfilling the dual property requirement for non-opaque material adhesiveness necessary for use in flexible displays.

This paper mainly focuses on the suitability of using kenaf/polyester composites for potential plastic encapsulated electronic packaging. The usage of natural fiber, such as kenaf fiber which has been recognized as for green fiber is the potential substitute in plastic encapsulation composites. The use of microsized Alumina Trihydrate (ATH) as the additive in the formulations is to reduce the hygroscopic tendency of the composites. In this research, there are six compositions of the plastic encapsulation composites fabricated using hand lay-up followed by the vacuum infusion method. Moreover, the amount of additive of microsized ATH was varied (2.5, 5 and 7.5 wt%) in kenaf/polyester composites is also to observe the performance of mechanical properties such as tensile, flexural and impact strength. Then, evidence that the effect of microsized ATH additive had occurred between kenaf/polyester was identified by using Scanning Electron Microscope (SEM). The results revealed that the addition of microsized ATH at 5 wt% of kenaf/polyester composites improved slightly higher than unfilled ATH for the tensile and flexural strength by 1.7% and 2.13%. Also, the impact strength can reach up to 28% for 5 wt% ATH filled and the reduced water uptake was observed when increasing of microsized ATH content from 2.5 to 7.5 wt%. Thus, this suitability of microsized ATH as an additive could be a potential material used for plastic encapsulation for electronic packaging applications.

Bending resistance is regarded as a significant factor in achieving the widespread application of copper foils. This paper proposed a novel double-cross rolling process, which improved the bending fatigue life of copper foils by as much as 101% in comparation with conventional rolling. In this study, an investigation was conducted into the effects of double-cross rolling on the microstructure and texture of copper foils and the strengthening mechanism during the bending test was discussed. Results show that double-cross rolling could change the deformation behavior on bright and matt surfaces, resulting in equiaxed grains on both surfaces and some fine grains. Both surfaces were dominated by Brass and S textures, which can be attributable to from non-uniform and shear deformation respectively. Weak Goss and Cube textures resulted from the fine grains remaining after heat treatment. After double-cross rolling, the strain induced subgrains of copper foils facilitated the migration of grain boundary and grain rotation, thus improving bending property.