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The purpose of this paper is to report on a method of synthesis of TiO₂‐SiO₂ oxide composites characterised by spherically shaped particles with sizes in the micrometric ranges, which can be applied as a new generation of textile/TiO₂‐SiO₂ composites with barrier properties against UV radiation. Synthesis and characterisation of TiO2‐SiO2 oxide composites with a high degree of dispersion were performed, and their influence on the barrier properties of textile fabrics was investigated.

The precipitation was performed with the use of solutions of titanium sulphate and sodium silicate as the precipitating agent, which are cheap alternatives to organic precursors of Ti and Si. The reaction was conducted in an emulsion system, where cyclohexane was used as the organic phase and non‐ionic surfactants NP3 and NP6 as emulsifiers were applied.

The direction of substrate supply, concentration of the reagents and their ratio and other conditions of precipitation process were found to significantly affect the physicochemical parameters of the pigments obtained. A possibility is provided of manufacturing a new generation of textile/TiO2‐SiO2 composites with barrier properties against UV radiation.

Titanium sulphate, sodium silicate, cyclohexane as the organic phase, and non‐ionic surfactants NP3 and NP6 as emulsifiers, were used.

Synthesis of a new generation of textile/TiO2‐SiO2 composites with barrier properties against UV radiation has been performed. Textile fabrics modified with hybrid composites demonstrated high absorption of UV radiation over the full wavelength range.

Determination of optimum conditions of TiO2‐SiO2 oxide composites precipitation to obtain products with desired physicochemical, dispersive and structural properties. Development of nano‐structural textile composites with barrier properties, protecting against UV radiation.

The purpose of this paper is to obtain ZnO‐SiO₂ oxide composites of low bulk density, high homogeneity and consisting of the smallest possible particles. The optimum parameters of precipitation of ZnO‐SiO₂ oxide composites impregnated with natural latex rubber were established. The formation and impregnation the ZnO‐SiO₂ oxide composites were made to occur simultaneously.

The influence of non‐ionic surfactants added during the precipitation process on the physico‐chemical properties of the oxide systems obtained was investigated. The products were characterised by determination of bulk density, absorption capacities of water and paraffin oil, particle size distribution (applying NIBS and laser diffraction methods), as well as SEM observations of surface morphology and microstructure. Moreover, the colorimetric characteristics of the oxide composites obtained and sedimentation profiles in water were analysed. Energo‐dispersive microanalysis of the products enabled determination of the content of ZnO and SiO₂. The surface area (BET) and the size and volume of pores were also estimated.

Modification of the oxide composites with nonylphenylpolyoxyethyleneglycol ethers was found to improve the basic physico‐chemical parameters of the ZnO‐SiO₂ hybrid systems and to change the character of its surface to become more hydrophobic. The conditions in which samples with the best properties were obtained were concluded to be optimum.

Only the selected non‐ionic surfactants were applied as modifying agents of ZnO‐SiO₂.

There is a possible application of ZnO‐SiO₂ oxide composites as activators of rubber compounds and barrier materials in textiles.

The proposed method of ZnO‐SiO₂ oxide composite synthesis in the process of precipitation with simultaneous modification with non‐ionic surfactants provides products with desirable dispersive‐morphological parameters and a hydrophobic surface character.

This study aims to observe the coloring efficacy of graphite (G) and nano bentonite clay (BCNPs) on the adsorption of Basic Blue 5 dye from residual dye bath solution.

Some factors that affected the adsorption processes were examined and found to have significant impacts on the adsorption capacity such as the initial concentration of G and/or BCNPs (Co: 40–2,320 mg/L), adsorbent bath pH (4–9), shaking time (30–150 min.) and initial dye concentration (40–200 mg/L). The adsorption mechanism of dye by using G and/or BCNPs was studied using two different models (first-pseudo order and second-pseudo order diffusion models). The equilibrium adsorption data for the dye understudy was analyzed by using four different models (Langmuir, Freundlich, Temkin modle and Dubinin–Radushkevich) models.

It has been found that the adsorption kinetics follow rather a pseudo-first-order kinetic model with a determination coefficient (R²) of 0.99117 for G and 0.98665 for BCNPs. The results indicate that the Freundlich model provides the best correlation for G with capacities q_max = 2.33116535 mg/g and R² = 0.99588, while the Langmuir model provides the best correlation for BCNPs with R² = 0.99074. The adsorbent elaborated from BCNPs was found to be efficient and suitable for removing basic dyes rather than G from aqueous solutions due to its availability, good adsorption capability, as well as low-cost preparation.

There is no research limitation for this work. Basic Blue 5 dye graphite (G) and nano bentonite clay (BCNPs) were used.

This work has practical applications for the textile industry. It is concluded that using graphite and nano bentonite clay can be a possible alternative to adsorb residual dye from dye bath solution and can make the process greener.

Socially, it has a good impact on the ecosystem and global community because the residual dye does not contain any carcinogenic materials.

The work is original and contains value-added products for the textile industry and other confederate fields.

Artificial electromagnetic (EM) medium and devices are designed with integrated micro- and macro-structures depending on the EM transmittance performance, which is difficult to fabricate by the conventional processes. Three-dimensional (3D) printing provides a new solution for the delicate artificial EM medium. This paper aims to first review the applications of 3D printing in the fabrication of EM medium briefly, mainly focusing on photonic crystals, metamaterials and gradient index (GRIN) devices. Then, a new design and fabrication strategy is proposed for the EM medium based on the 3D printing process, which was verified by the implementation of a 3D 90o Eaton lens based on GRIN metamaterials.

A new design and manufacturing strategy driven by the physical (EM transmittance) performance is proposed to illustrate the realization procedures of EM medium based device with controllable micro- and macro-structures. Stereolithography-based 3D printing process is used to obtain the designed EM device, an GRIN Eaton lens. The EM transmittance of the Eaton lens was validated experimentally and by simulation.

A 3D 90o Eaton lens was realized based on GRIN metamaterials structure according to the proposed design and manufacturing strategy, which had the broadband (12-18 GHz) and low loss characteristic. The feasibility of 3D printing for the artificial EM medium and GRIN devices has been verified for the further real applications in the industries.

The applications of 3D printing in artificial EM medium and devices were systematically reviewed. A new design strategy driven by physical performance for the EM device was proposed and validated by the firstly 3D printed 3D Eaton lens.

This paper aims to investigate the influence of scan speed on the corrosion and tribocorrosion features of the CoCrMoW samples fabricated via the selective laser melting (SLM) process.

CoCrMoW samples were produced by SLM at different scan speeds. Produced samples were made via structural surveys (X-ray diffraction examinations and scanning electron microscopic analyses), hardness measurements and electrochemical and tribocorrosion experiments.

Outcomes displayed that the corrosion and tribocorrosion properties of CoCrMoW alloy were significantly influenced by scanning speeds. Also, these properties of the alloy increased with increasing scanning speeds. CoCrMoW samples produced at a laser scan speed of 1,000 mm/s showed the best resistance to corrosion and tribocorrosion. This could be related to the high hardness and low grain structure of the fabricated samples.

This paper may be a practical reference and offers insight into the effect of scanning speeds on the increase of hardness, tribological and corrosion performance of CoCrMoW alloys. This study can help in the further advancement of cobalt-chromium alloy in situ produced by SLM for both electrochemical and tribocorrosion behavior for biomedical applications.