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The purpose of this paper is to invent a new functional coated fabric based on nanomaterials to shield UV and IR. Multifunctional surface coatings with ultraviolet (UV)/near infrared radiations protection and waterproof were widely applied in outdoor fabrics. Herein, ultrafine TiO2 and nano-antimony doped tin dioxide (ATO) were prepared and embedded into water-based polyurethane (PU) coatings and then coated on the nylon fabric.

ATO was prepared using the sol–gel method and the two powders were dispersed by ball milling. The results of zeta potential and particle size distribution showed that the ultrafine TiO2 and nano-ATO could be stably dispersed in water at pH 8 with the presence of sodium polycarboxylate. The optimal process was screened out by orthogonal design and scanning electron microscopy (SEM), UV protection, thermal insulation and water-pressure resistance were tested. SEM images indicated the nanoparticles could be uniformly dispersed in the coatings.

The effect of UV prevention can get to UPF > 50, UVA < 5 per cent, which meet up with the AATCC 183-2014. Coatings can effectively lower the temperature of fabric surface by 8∼9ºC through the self-made closed test system and by 3ºC through the open test system.

These PU coatings are environment-friendly and adhesive to impart waterproof, UV-proof and thermal insulation properties to nylon fabrics by coating finishing.

In recent times, there has been a growing interest in buoyancy-induced heat transfer within confined enclosures due to its frequent occurrence in heat transfer processes across diverse engineering disciplines, including electronic cooling, solar technologies, nuclear reactor systems, heat exchangers and energy storage systems. Moreover, the reduction of entropy generation holds significant importance in engineering applications, as it contributes to enhancing thermal system performance. This study, a numerical investigation, aims to analyze entropy generation and natural convection flow in an inclined square enclosure filled with Ag–MgO/water and Ag–TiO2/water hybrid nanofluids under the influence of a magnetic field. The enclosure features heated slits along its bottom and left walls. Following the Boussinesq approximation, the convective flow arises from a horizontal temperature difference between the partially heated walls and the cold right wall.

The governing equations for laminar unsteady natural convection flow in a Newtonian, incompressible mixture is solved using a Marker-and-Cell-based finite difference method within a customized MATLAB code. The hybrid nanofluid’s effective thermal conductivity and viscosity are determined using spherical nanoparticle correlations.

The numerical investigations cover various parameters, including nanoparticle volume concentration, Hartmann number, Rayleigh number, heat source/sink effects and inclination angle. As the Hartmann and Rayleigh numbers increase, there is a significant enhancement in entropy generation. The average Nusselt number experiences a substantial increase at extremely high values of the Rayleigh number and inclination.

This numerical investigation explores advanced applications involving various combinations of influential parameters, different nanoparticles, enclosure inclinations and improved designs. The goal is to control fluid flow and enhance heat transfer rates to meet the demands of the Fourth Industrial Revolution.

In a 90° tilted enclosure, the addition of 5% hybrid nanoparticles to the base fluid resulted in a 17.139% increase in the heat transfer rate for Ag–MgO nanoparticles and a 16.4185% increase for Ag–TiO2 nanoparticles compared to the base fluid. It is observed that a 5% nanoparticle volume fraction results in an increased heat transfer rate, influenced by variations in both the Darcy and Rayleigh numbers. The study demonstrates that the Ag–MgO hybrid nanofluid exhibits superior heat transfer and fluid transport performance compared to the Ag–TiO2 hybrid nanofluid. The simulations pertain to the use of hybrid magnetic nanofluids in fuel cells, solar cavity receivers and the processing of electromagnetic nanomaterials in enclosed environments.

The review glances upon the colorants used for printing on ceramic substrates by ink jet technology and techniques, chemistry involved during the selection of the colorants.

The ink jet technology is an easy and a convenient technique, specially designed colorants are used for such applications with tailor made properties and features.

New developments in technology and chemistry of colorants to achieve successes in application studies of ceramic substrates.

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This review glances upon the history, development and practical approach of the current techniques with available dyes and pigments and the techniques involved during the synthesis and application.

The review paper provides information about the development of the inkjet technique on ceramics and available colorants with methods.

The purpose of this paper is to investigate the effect of inclined magnetic field, variable viscosity and Cattaneo–Christov heat and mass flux theories on the steady MHD free convective boundary layer flow of viscous, incompressible and electrically conducting water-driven silver and titanium-oxide nanofluids over a vertical stretching sheet.

The boundary layer equations of momentum, energy and nanoparticle concentration are partial differential equations in nature, which are reduced to nonlinear ordinary differential equations by means of similarity transformations. The resulting nonlinear equations are solved analytically by means of optimal homotopy analysis method.

Assessments with numerical results are performed and are found to be in an excellent agreement. Numerical results of the skin friction factor, the local Nusselt number and the local Sherwood number are obtained through tables. The effects of various physical parameters on the velocity, temperature and nanoparticles fraction are incorporated through graphs. The study analyzes the efficiency of heat transfer of nanofluids in cooling plants and rubber sheets.

No research works have been conducted to evaluate the effects of various physical phenomena on the copper and titanium nanofluids flow.

A team from Macpherson Paints' marketing department at Bury, Lancashire, are seen here celebrating their achievement of reaching the final four in a national marketing game.

This paper aims to coat ternary composite NiBP-graphite films by Dynamic Chemical Plating “DCP” technique with a growth rate of at least 5 μm/h, which makes this technique a worthy candidate for production of composite films. Electroless nickel plating method can be used to deposit nickel–phosphorous and nickel–boron coatings on metals or plastic surface. However, restrictions such as toxicity, short lifetime of the plating-bath and limited plating rate have limited applications of conventional electroless processes.

DCP is an alternative for producing metallic deposits on non-conductive materials and can be considered as a modified electroless coating process. Using a double-nozzle gun, two different solutions containing the precursors are sprayed simultaneously and separately onto the surface. With this technique, NiBP-graphite films are fabricated and their corrosion and tribological properties are investigated.

With a film thickness of 2 μm, tribological analysis confirms that these coatings have favorable anti-friction and anti-wear properties. Corrosion resistance of NiBP-graphite composite films was investigated, and it was found that graphite incorporation significantly enhances corrosion resistance of NiBP films.

DCP is faster and simpler to perform compared to other electroless deposition techniques. Using a double-nozzle gun, metal salt solution and reducing agents are sprayed to the surface, forming a deposit. Previously, coatings such as Cu, Cu-graphite, Cu-PTFE, Ni-B-TiO2, Ni-P, Ni-B-P and Ni-B-Zn with favorable compactness and adherence by DCP were reported. In this paper, the authors report the application of the DCP technique for depositing NiBP-PTFE nanocomposite films.

This paper aimed to prepare a kind of ZnS nanoparticles/poly(phenylene vinylene) (PPV) nanofibre and investigate its properties. Because the ZnS nanoparticles are important optoelectronic materials, their incorporation into one-dimensional (1D) nanoscale polymer matrices should be a meaningful subject for electrospinning.

ZnS/PPV composite nanofibres with an average diameter of 600 nm were successfully prepared by a combination of the in situ method and electrospinning technique. The nanofibres were electrospun from Zn(CH3COO)2·2H2O and PPV precursor composite solution, and the ZnS/PPV fibres were obtained by exposure of the electrospun fibres to H₂S gas to prepare ZnS nanoparticles in situ. Such fibres were characterised using X-ray Diffraction (XRD), Fourier transform infrared, transmission electron microscope (TEM), scanning electron microscope and photoluminescence (PL). The photoelectric properties of the fibres obtained were also investigated.

XRD patterns proved that ZnS nanocrystals generated in the composite nanofibres. The TEM image showed that the nanocrystals were homogeneously dispersed in the nanofibres. The PL spectrum of ZnS/PPV composite nanofibres exhibited a blue shift relative to the PPV nanofibres. I-V curve of the single nanofibre device under 5.76 mW/cm2 light illumination showed that the composite nanofibres have good photoelectric properties.

The comparisons of advantages between ZnS/PPV nanofibres with similar nanofibres will be further expanded in a later research.

Results demonstrate the promise of these novel nanostructures as ultraminiature photodetectors with the potential for integration into future hybrid nanophotonic devices and systems.

The integration of inorganic semiconductor nanoparticles into organic conjugated polymers leads to composite materials with unique physical properties and important application potential. In this work, ZnS nanoparticles were introduced into PPV by an in situ method, so as to obtain a kind of novel 1D nanomaterials with good photoelectric properties.

This study aims to apply the lattice Boltzmann method to investigate the natural convection flows utilizing nanofluids in a semicircular cavity. The fluid in the cavity is a water-based nanofluid containing Al₂O₃ or Cu nanoparticles.

The study has been carried out for the Rayleigh numbers from 104 to 106 and the solid volume fraction from 0 to 0.05. The effective thermal conductivity and viscosity of nanofluid are calculated by the models of Chon and Brinkman, respectively. The effects of solid volume fraction on hydrodynamic and thermal characteristics are investigated and discussed. The averaged and local Nusselt numbers, streamlines, temperature contours for different values of solid volume fraction and Rayleigh number are illustrated.

The results indicate that more solid volume fraction corresponds to more averaged Nusselt number for both types of nanofluids. It is also found that the effects of solid volume fraction of Cu are stronger than those of Al₂O₃.

Numerical study of natural convection of nanofluid in a semi-circular cavity with lattice Boltzmann method in the presence of water-based nanofluid containing Al₂O₃ or Cu nanoparticles.

The purpose of this paper is to develop new types of direct expansion method of moments (DEMM) by using the n/3th moments for simulating nanoparticle Brownian coagulation in the free molecule regime. The feasibilities of new proposed DEMMs with n/3th moments are investigated to describe the evolution of aerosol size distribution, and some of the models will be applied to further simulation of physical processes.

The accuracy and efficiency of some kinds of methods of moments are mainly compared including the quadrature method of moments (QMOM), Taylor-expansion method of moments (TEMOM), the log-normal preserving method of moments proposed by Lee (LMM) and the derived DEMM in this paper. QMOM with 12 quadrature approximation points is taken as a reference to evaluate other methods.

The newly derived models, namely DEMM(4/3,4) and DEMM(2,6), as well as the previous DEMM(2,4), are considered to be qualified models due to their high accuracy and efficiency. They are confirmed to be valid and alternative models to describe the evolution of aerosol size distribution for particle dynamical process involving the n/3th moments.

The n/3th moments, which have clear physical interpretations when n stands for first several integers, are first introduced in the DEMM method for simulating nanoparticle Brownian coagulation in the free molecule regime.