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The purpose of this study is to theoretically probe the shape impacts of nano-particle on boundary layer flow of nano-fluid toward a stretching cylinder with heat-transmission effects. The base fluid used for this study is pure water, and aluminum oxide nano-particles are suspended in it. Four different shapes of nano-particle, namely, cylindrical, brick, platelets and blades, are considered to carry out the study.

The problem is modelled mathematically and the nonlinear system of equations is attained by using appropriate transmutations. The solution of transmuted equations is achieved by utilizing a shooting technique with Fourth-Fifth order Runge–Kutta Fehlberg scheme. Numerically attained results are elucidated through graphs and tables which are further compared under limiting cases with existing literature to check the validity of the results.

It is observed that fluid velocity and temperature of cylindrical shaped water nano-fluids are more than the nano-fluid having brick-shaped nano-particles. Moreover, it is seen that the nano-fluids suspended with platelets-shaped nano-particles have higher velocity and temperature than the nano-fluids containing blade-shaped nano-particles. The curvature parameter and nano-particles volume fraction have increasing effects on flow velocity and temperature of nano-fluids containing all types of nano-particle shapes.

Numerous authors have examined the impacts of nano-particle shapes on characteristics of heat transfer and fluid flow. However, to the best of the authors’ knowledge, the shape impacts of nano-particles on boundary layer flow of nano-fluid toward a stretching cylinder with heat-transmission effects have not been discussed. So, to fulfill this gap, the present paper explicates the impacts of various nano-particle shapes on Al₂O₃–water-based nano-fluid flow past a stretching cylinder with heat-transfer effects.

The purpose of this paper is to develop a new method for biomolecular recognition based on light scattering of ZnS:Mn nano‐particle functionalised with biotin.

ZnS:Mn nano‐particles was successfully synthesised from quaternary water‐in‐oil micro‐emulsion system. The addition of biotin and the subsequent specific binding events alter the dielectric environment of the nano‐particle, resulting in a spectral shift of the particle plasmon resonance. Cyclohexane was used as oil, Triten X‐100 as surfactant, n‐hexanol as a co‐surfactant and mercaptoethanol for the best linking of biological part to nano‐particle. Measurement of the content of avidin was achieved by detecting the Department of Biomedical Engineering change in the excited emission. For qualitative and quantitative analyses of this product, scanning electron microscopy, transmission electron microscopy, energy dispersive X‐ray spectroscopy and spectrograph techniques were used.

It was observed that with reducing particle size, emission shifted to the lower wave lengths. In addition, with conjugation between avidin and biotin by mercaptoethanol in biologic media, spectral emission decreased.

The method developed could be utilised for synthesis of a variety of ZnS:Mn nano‐particles for a wide range of diagnostic applications.

The method for biomolecular recognition based on light scattering of ZnS:Mn nano‐particle functionalised with biotin developed was novel.

The purpose of this paper is to evaluate the water vapour permeability and mechanical properties of a solventless epoxy – nano‐platelet nano‐composite system compatibilised with an amino‐silane.

The performance of a nano‐platelet reinforced coating composite was studied with reference to the water vapour permeability and mechanical properties. The effect of addition of coupling agent on these properties was also studied.

The addition of nano‐platelets to the solventless epoxy system resulted in an increased water vapour permeability which was reduced on the addition of coupling agent. The talc‐based films showed a better performance as compared to the montmorillonite based coatings. The mechanical properties of the films increased though the addition of coupling agent showed a larger increase. The gloss of the coatings was compromised on addition of nano‐particles. Comparing coupling agents, the primary amine based silane showed better performance and lower tactoid formation as compared to the secondary amino silane based coupling agent.

The addition of nano‐particles to solventless and other eco‐friendly coatings needs to be studied further. Various other coupling agents could be studied to further improve the performance of these coatings.

The formulation developed could be used to reduce the water vapour permeability and performance of solventless epoxy coatings, which could be used as anti‐corrosive coatings.

The study of performance of nano‐particles in solventless epoxy coatings and their effect on water vapour permeability could increase performance of these reduced VOC coatings.

Any change in physical performance of the fibre corresponds to a change in its molecular structure. Basically polyester is hydrophobic in nature due to the absence of attracting polar groups and the dense packing in its polymeric structure. Due to the dense packing in polymeric structure and lack of hydroxyl groups of polyester it does not absorb water hence breathability is poor. The possibility of using air and oxygen plasma treatments for fibre surface activation to facilitate the improvement of hydrophilicity is attempted and has been improved. The purpose of this paper is to study the possibility of engineering the multifunctional of fabrics.

The treated fabric is evaluated through measuring the ultraviolet protection factor, thermal resistance, and antibacterial activity properties. Scanning electron microscopy and transmission electron microscopy graphs show deposition of nano particles (NPs) of Chitosan, TiO₂ and ZnO onto the fibre after washing several times.

Air plasma-nano Chitosan treatment affects positively the antibacterial activity, thermal resistance of the fibre and air plasma-nano TiO₂ and ZnO the fibre protection against ultraviolet rays. Furthermore, the plasma treatment solves an environmental problem which offers safe production process and working place and decreases the unit cost.

The authors are confident that textiles will adopt this technology in the future.

The purpose of this paper is to investigate the tribological properties of a textured lubricating wear-resistant coating modified by nano-SiC at a high temperature. Its aim is to explore the influence of a new composite method on the organisation and structure of sprayed coatings as well as the evolution rules governing their high-temperature tribological properties.

A KF301/WS2 lubricating, wear-resisting, coating was prepared on matrix material GCr15 by applying supersonic plasma spraying technology. On the basis of this sample, using nano-SiC particles as a filler, the KF301/WS2 nano-modified coating with its round, pit-type texture was prepared by laser re-melting technology and a surface texturing technique. Two kinds of coating micro-organisations and structures were examined by scanning electron microscopy, and the tribological properties of both the modified and conventional coatings were studied at a high temperature.

Results showed that nano-particles could effectively improve the coating micro-structure, and make the structure denser and more uniform, thus significantly increasing the wear resistance of the coating. When the friction and wear processes were stable, the friction coefficient decreased by 13 per cent, while the wear loss decreased by 45.9 per cent.

This research concentrating on the study of the process and performance of coatings doped with nano-particles by laser re-melting incorporating simultaneous surface texturing, and studies of their high-temperature tribological properties. That is because applying nano-particle modification technology to the development of wear-resistant coatings, and by applying the nano-particles to such coatings by thermal spraying technology, they can achieve a modification of the coating which makes the structure denser and more uniform.

The study aims to verify and establish the result of the most suitable optimization approach for higher performance and lower emission of a variable compression ratio (VCR) diesel engine. In this study, three types of test fuels are taken and tested in a variable compression ratio diesel engine (compression ignition). The fuels used are conventional diesel fuel, e-diesel (85% diesel-15% bioethanol) and nano-fuel (85% diesel-15% bioethanol-25 ppm Al₂O₃). The effect of bioethanol and nano-particles on performance, emission and cost-effectiveness is investigated at different load and compression ratios (CRs). The optimum performance and lower emission of the engine are evaluated and compared with other optimization methods.

The test engine is run by diesel, e-diesel (85% diesel-15% bioethanol) and nano-fuel (85% diesel-15% bioethanol-25 ppm Al₂O₃) in three different loadings (4 kg, 8 kg and 12 kg) and CR of 14, 16 and 18, respectively. The optimum value of energy efficiency, exergy efficiency, NO_X emission and relative cost variation are determined against the input parameters using Taguchi-Grey method and confirmed by response surface methodology (RSM) technique.

Using Taguchi-Grey method, the maximum energy and exergy efficiency, minimum % relative cost variation and NO_X emission are 24.64%, 59.52%, 0 and 184 ppm, respectively, at 4 kg load, 18 CR and fuel type of nano-fuel. Using RSM technique, maximum energy and exergy efficiency are 24.8% and 62.9%, and minimum NO_X emission and % cost variation are 208.4 ppm and –6.5, respectively, at 5.2 kg load, 18 CR and nano-fuel. The RSM is suggested as the most appropriate technique for obtaining maximum energy and exergy efficiency, and minimum % relative cost; however, for lowest possible NO_X emission, the Taguchi-Grey method is the most appropriate.

Waste rice straw is used to produce bioethanol. 4-E analysis, i.e. energy, exergy, emission and economic analysis, has been carried out, optimized and compared.

The purpose of this paper is to investigate the effects of nano‐titanium dioxide and nano‐silicon dioxide particles on the mechanical and antimicrobial properties of denture base resin.

Nano‐titanium dioxide and nano‐silicon dioxide particles were introduced to heat‐curing denture base resin to prepare composites. Electronic universal testing machine and friction tester were used to test tensile strength and frictional resistance properties of the samples prepared, respectively; also, film adhesion method was used to test the in vitro antimicrobial activity against Candida albicans and Streptococcus mutans.

Addition of nano‐titanium dioxide particles could improve the antimicrobial property of denture base resin, and addition of nano‐silicon dioxide particles could improve the tensile strength and frictional resistance of denture base resin. Mixture of the two nano‐particles, at a certain ratio, could improve the tensile strength, frictional resistance and antimicrobial property of denture base resin to a certain extent.

Nano‐titanium dioxide and nano‐silicon dioxide denture base resin composites were obtained. The mechanical and antimicrobial properties of the composites were improved compared to the raw denture base resin.

Nano‐titanium dioxide and nano‐silicon dioxide denture base resin composites with excellent performance could be obtained. Longer service life, greater hardness and clearness helped improve the patients' quality of life. Limited work with respect to the improved denture base resin was performed, which could form the theme of a future study. The outcomes of the research reported here set a new milestone in the field of denture base resin.

The purpose of this paper is to analyze the thermal, hydraulic and entropy generation characteristics for the magneto-hydrodynamic (MHD) pressure-driven flow of Al₂O₃-water nanofluid through an asymmetric wavy channel.

Galerkin finite element method is used to solve the governing transport equations numerically within the computational domain using the appropriate boundary conditions. The temperature and flow fields are computed by varying Reynolds number (Re), Hartmann number (Ha) and nano-particle volume fraction (ϕ) in the following range: 10 ≤ Re ≤ 500, 0 ≤ Ha ≤ 75 and 0 ≤ ϕ ≤ 5%.

The formation of the recirculation zones in the wavy passages, the size of it and the strength of the vortices formed can be modulated by the application of the magnetic field. The overall heat transfer rate increases with Ha for all ϕ both for a lower and higher regime of Re although the enhancement is more for lower values of Re and nanofluids as compared to base fluid and for intermediate values of Re, the effect of a magnetic field is almost insignificant. The magnetic performance factor (PF_magnetic) decreases with Ha although the rate of decrement varies with Re. The increase ϕ also enhances PF_magnetic especially at lower and higher values of Re. The addition of nano-particle enhances the entropy generation at lower values of the Re, while the opposite effect is seen for higher values of Re.

The present study has enormous practical relevance for the design of heat exchanger applied for solar collectors, process plants, textile and aerospace applications.

The combined effects on the heat transfer rate and the associated pressure drop penalty due to the applied magnetic field for the flow of nanofluid through an asymmetric wavy channel have not been reported to date. The effect of the magnetic field on the formation of recirculation zones and hot spot intensity in the asymmetric wavy channel has been examined in detail. The PF_magnetic is investigated first time for the MHD nanofluid flow through a wavy channel.

The majority of first-principle, homogenisation techniques makes use of the dipole terms of a small particle radiation, and, consequently, the respective dipole polarisabilities. This paper aims to take the next step and propose a new systematic technique for extracting the quadrupolarisability of planar metamaterial scatterers.

Firstly, it is assumed that the particle, under study, can be modelled as a set of dipole and quadrupole moments, and by utilising the respective polarisabilities, the far-field response of the scatterer is calculated. Then, the far-field scattering field of the particle is constructed in terms of the dipole and quadrupole moments, which, in turn, are expressed as a function of the unknown polarisabilities. Finally, the desired polarisabilities are retrieved by a system of equations, which involves numerically derived electric field values at specific positions around the scatterer.

The quadrupolarisability of planar metamaterial particles is extracted, through an easy to use, yet very accurate and efficient methodology. Moreover, the proposed technique is verified via comprehensive comparisons of consequently computed and simulated total radiated power values, which reveal its advantages and applicability limits. Finally, the total radiation power contribution of each calculated, individual multipole is provided, to further investigate the radiation mechanism of all nano-particles under study.

The initial and most important step of extracting a single quadrupolarisability of a planar realistic nano-particle has been performed, herein, for the first time. The addition of the respective quadrupole in the scattering model, shifts the multipole approximation limit upwards in terms of frequency, and, therefore, nano-particles with quadrupole resonances can, now, be precisely represented via polarisabilities for various metamaterial or metasurface applications.

The purpose of this paper is to study the effect of nano hydroxyapatite (HA) and graphene oxide (GO) particles on thermal and mechanical performances of 3D printed poly(ε-caprolactone) (PCL) filaments used in bone tissue engineering (BTE).

Raw materials were prepared by melt blending, followed by 3D printing via 3D Discovery (regenHU Ltd., CH) with all fabricating parameters kept constant. Filaments, including pure PCL, PCL/HA and PCL/GO, were tested under the same conditions. Several techniques were used to mechanically, thermally and microstructurally evaluate properties of these filaments, including differential scanning calorimetry, tensile test, nano indentation and scanning electron microscope.

Results show that both HA and GO nano particles are capable of improving mechanical performance of PCL. Enhanced mechanical properties of PCL/HA result from reinforcing effect of HA, while a different mechanism is observed in PCL/GO, where degree of crystallinity plays an important role. In addition, GO is more efficient at enhancing mechanical performance of PCL compared with HA.

For the first time, a systematic study about effects of nano HA and GO particles on bioactive scaffolds produced by additive manufacturing for BTE applications is conducted in this work. Mechanical and thermal behaviors of each sample, pure PCL, PCL/HA and PCL/GO, are reported, correlated and compared with literature.