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The purpose of this paper on the one hand is to reduce the sintering temperature, shorten the sintering time and improve the electrical properties of the sample through the two-step flash sintering method and on the other hand is to study the effect of electric field on the phase structure, microstructure and electrical properties of the flash sintering sample.

In this paper, (Mg_1/3Ta_2/3)_0.01Ti_0.99O₂ giant dielectric ceramics were prepared by conventional sintering and two-step flash sintering, respectively. Further, the effect of electric field (600–750 V/cm) on the electrical properties of (Mg_1/3Ta_2/3)_0.01Ti_0.99O₂ giant dielectric ceramics was studied.

The results show that compared with the conventional sintering, the sintering temperature of the two-step flash sintering can be reduced by 200°C and the sintering time can be shortened by 12 times. All sintered samples were single rutile TiO₂ structure. Compared with conventional sintering, two-step flash sintering samples have finer grain size. The two-step flash sintered sample has similar dielectric properties to the conventional sintered sample. The dielectric constant of flash sintered samples decreases with the increase of electric field. When the electric field is 700 V/cm, the ceramic sample has the optimal dielectric properties, where the dielectric constant is approximately 5.5 × 10³ and the dielectric loss is about 0.18 at 1 kHz. Impedance spectroscopy analysis shows that the excellent dielectric properties are attributed to the internal barrier layer capacitance model.

This paper not only provides a new method for the preparation of co-doped TiO₂ giant dielectric ceramics but also has great potential in greatly improving efficiency and saving energy.

The purpose of this paper is to analyze various properties of anatase titanium dioxide (TiO₂) nanoparticles. Further, it proposes to implement Linear Combinations of Atomic Orbitals (LCAO) basis set under the framework of density functional theory and outline how LCAO is able to provide improved results in terms of various mechanical properties rather than plane wave and other theoretical results.

This paper provides an exploratory study on anatase TiO₂ by implementing OLCAO–DFT–LDA–LBFGS–EOS–PZ algorithms to find out various ground-level properties. The data so obtained are complemented by various analysis using mathematical expressions, description of internal processes occurred and comparison to others’ analytical results.

The paper provides some empirical insights on how mechanical properties of anatase TiO₂ improved by implementing LCAO methodology. From the analysis of electronic properties, it is seen that the anatase TiO₂ supports the inter band indirect transition from O-2p in valence region to Ti-3d in the conduction region.

Most of the electronic properties are underestimated because a single exchange-correlation potential is not continuous across the gap. This gap can be enhanced by implementing Green’s function in place of DFT and the other way is to implement self-interaction correction.

The use of anatase TiO₂ is primarily used for catalytic applications. This is also used to enhance the quality of paper in the paper industry. Additionally, this is used as a prime ingredient in cosmetic industry.

This paper fulfills an identified need to study how LCAO, another basis set, plays an important role in improving material properties.

The purpose of this paper is to improve the conductivity and processability of polyaniline (PANI).

The study opted for synthesis of the conductive PANI/polyvinyl alcohol (PVA) composite film, co-doped with 5-sulphosalicylic acid and sulphuric acid. Using an electrochemical method, a small amount of silver (Ag) was electrodeposited on the film. The PVA/PANI and PVA/PANI/Ag composite films were characterised by scanning electron microscope, X-ray diffraction and infrared. The composite deposition mechanism of the composite film was investigated by cyclic voltammetry for the first time.

The conductivity of the optimum PVA/PANI composite film reached 21.2 S · cm⁻¹.Then, a small amount of Ag was deposited on the PVA/PANI film, and the conductivity significantly increased by 1250 S · cm⁻¹. Through appropriate degree of stretching, the conductivity of the films was enhanced. The results indicate that uniform PVA/PANI fibres and dendritic Ag can combine to form complete three-dimensional conductive networks that exhibit better conductivity and mechanical properties. The cyclic voltammetry curves reveal that the dedoping potential of PANI was more negative than the reduction potential of Ag. Therefore, the procedure for the deposition of Ag on the PANI/PVA composite film cannot decrease the conductivity.

This paper for the first time described and revealed the effective and practical synthesis approach and composite mechanism to prepare multi-types metal-conductive polymer composites and improve the conductivity of a conductive polymer with a less expense and one-step electrochemical method.

This paper first explored galvanostatic oxidation to synthesise a PANI composite film to resolve the processability and conductivity of PANI by co-doped with mixed acids and deposited Ag on film. Furthermore, for the first time, the composite mechanism of metal and conductive polymer was studied.

The purpose of this paper is to investigate the reflective properties of titania (TiO2) nanoparticle‐based coating.

TiO2 nanoparticles, synthesised by sol‐gel method, were characterised by X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and ultraviolet‐visible absorption spectroscopy (UV‐vis). The coating material has been prepared by dispersing titania nanoparticles in an acrylic binder with different pigment to binder weight ratio. The reflectors were prepared by applying this coating material to different coating thicknesses to aluminium sheets.

In the study reported here, the coating material could produce reflectors with diffuse reflectance, ∼99 per cent, using coating material, having binder by weight ratio between 14 and 20 per cent, and thickness, 0.15 mm. On exposing the developed reflectors to different levels of illumination (upto 20,000 lux), they were still found to have diffuse reflectance of more than 96 per cent almost throughout the visible spectrum.

The fabricated reflectors find applications in commercial optical products, such as: reflective panels, luminaries, etc.

As of today, the reflective coatings used are of conventional type, which employ bulk TiO2 particles. In this study, we are reporting TiO2 nanoparticle‐based highly reflective coating. This is an original work, and, to the best of our knowledge, no one has ever reported on “TiO2 nanoparticle‐based reflective coatings”.

The main purpose of this study was to prepare the cotton fibers and cellulose powder by a layer of nano-crystalline-titanium dioxide (TiO₂) using the sol-gel sono-synthesis method to clean the wastewater containing reactive dye. Moreover, TiO₂ nano-materials are remarkable due to their photoactive properties and valuable applications in wastewater treatment.

In this research, TiO₂ was synthesized and deposited effectively on cotton fibers and cellulose powder using ultrasound-assisted coating. Further, tetra butyl titanate was used as a precursor to the synthesis of TiO₂ nanoparticles. Reactive dye (red 195) was used in this study. X-ray Diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy were performed to prove the aptitude for the formation of crystal TiO2 on the cotton fibers and cellulose powder along with TiO₂ nanoparticles as well as to analyze the chemical structure. Decoloration of the wastewater was investigated through ultraviolet (UV-Visible) light at 30 min.

The experimental results revealed that the decolorization was completed at 2.0 min with the cellulose nano TiO₂ treatment whereas cotton nano TiO₂ treated solution contained reactive dyestuffs even after the treatment of 2 min. This was the fastest method up to now than all reported methods for sustainable decolorization of wastewater by absorption. Furthermore, this study explored that the cellulose TiO₂ nano-composite was more effective than the cotton TiO₂ nano-composite of decoloration wastewater for the eco-friendly remedy.

Cotton fibers and cellulose powder with nano-TiO₂, and only reactive dye (red 195) were tested.

With reactive dye-containing wastewater, it seems to be easier to get rid of the dye than to retain it, especially from dyeing of yarn, fabric, apparel, and as well as other sectors where dyestuffs are used.

This research would help to reduce pollution in the environment as well as save energy and cost.

Decoloration of wastewater treatment is an essential new track with nano-crystalline TiO2 to fast and efficient cleaning of reactive dyes containing wastewater used as a raw material.

This paper aims to examine the investigations made on the corrosion behaviour of magnesium (Mg) substrate electrodeposited using different nano-materials.

This study uses nano-materials such as those of reduced graphene oxide (r-GO), titanium-di-oxide (TiO₂) and also r-GO/TiO₂ nano-composites (dispersed through ultra-sonication process) at 3-min time interval. Crystalline nature of synthesized TiO₂ is studied through X-ray diffraction and its pore volume is measured to be approximately 0.1851ccg-1 by Brunauer Emmett Teller analysis.

Surface morphology of the developed set of specimens inspected through scanning electron microscopy and energy dispersive spectroscopy establishes a clean surface coating and further witnesses for only minimal defects. Electrochemical behaviour of the developed coating is studied exhaustively using Tafel polarization and electrochemical impedance spectroscopy in 0.1 M Na₂SO₄ solution.

Incremental corrosion resistance exhibited by developed composite coating owes to the factors viz. chemical stability and hydrophobic tendency of TiO₂ and r-GO; these known engineering facts resist the flow of ions into the corrosive media and thereby reduce the rate of corrosion.

This study aims to study the simultaneous treatment of polyethylene terephthalate (PET) fabric with sodium hydroxide (NaOH) and TiO₂ nanoparticles (NPs).

PET fabrics loaded by TiO₂ NPs were investigated by the use of scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and Fourier transformed infrared spectroscopy (FT-IR). Factors affecting the finishing process such as NaOH and TiO₂ NPs concentrations, finishing duration and temperature were discussed.

The finished PET fabrics imparted new properties such as antimicrobial and ultraviolet protection factor protection, what is undoubtedly will increase the spread of this type of fabric and its use in new areas.

The method used mainly depends on activating the surface of PET fabrics by a chemical method, specifically NaOH to cause partial decomposition, which may lead to an environmental impact.

The obtained results revealed that the simultaneous treatment of PET fabric with NaOH and TiO₂ NPs showed antimicrobial and UV protection properties. They exhibited a strong antimicrobial activity and UV protection efficiency even after five washing cycles, indicating excellent laundering durability.

The approach has simplicity and implementability on an industrial scale without cost investment.

This paper aims to study the effects of MnO₂ on the ZnO–Bi₂O₃-based varistor prepared via flash sintering (FS)

MnO₂-doped ZnO–Bi₂O₃-based varistors were successfully prepared by the FS with a step-wise increase of the .current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm⁻¹. The FS process, microstructure and the electrical performance of ZnO–Bi₂O₃-based varistors were systematically investigated.

The doping of MnO₂ significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO₂ doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz.

FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi₂O₃ volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO₂ doping.

The low-temperature sintering of silica glass combined with additive manufacturing (AM) technology has brought a revolutionary change in glass manufacturing. This study aims to carry out in an attempt to achieve precious manufacturing of silicate glassy matrix through the method of slurry extrusion.

A low-cost slurry extrusion modelling technology is used to extrude silicate glassy matrix inks, composed of silicate glass powder with different amounts of additives. Extrudability of the inks, their printability window and the featuring curves of silicate glassy matrix are investigated. In addition, the properties of the low-temperature sintering green part as a functional part are explored and evaluated from morphology, hardness and colour.

The results showed that the particle size was mainly distributed from 1.4 µm to 5.3 µm, showing better slurry stability and print continuity. The parameters were set to 8 mm/s, 80% and 0.4 mm, respectively, to achieve better forming of three-dimensional (3D) samples. Besides, the organic binder removal step was concentrated on 200°C–300°C and 590°C–650°C was the fusion bonding temperature of the powder. The hardness values of 10 test samples ranged from 588 HL to 613 HL, which met the requirements of hard stones with super-strong mechanical strength. In addition, the mutual penetration of elements caused by temperature changes may lead to a colourful appearance.

The custom continuous AM technology enables the fabrication of a glass matrix with 3D structural features. The precise positioning technology of the glass matrix is expected to be applied more widely in functional parts.

The purpose of this study is to develop a multifunctional coating layer based on nitrocellulose (NC)/acrylic resins containing precipitated silica and kaolin and investigate its suitability for use in packaging applications.

Different loading levels (1 and 5 Wt.%) of precipitated silica or kaolin particles were incorporated into NC/acrylic-based coating formulations and applied on low-density polyethylene (LDPE) films. The coatings and coated LDPE films were characterized in terms of structural, physical, mechanical, thermal, optical, surface, morphological and water vapor barrier properties.

The glossiness of the coating formulations decreased by increasing the precipitated silica and kaolin content. The incorporation of kaolin (1 and 5 Wt.%) and precipitated silica (1 Wt.%) had no significant effect on the melting temperature of LDPE film; however, with the addition of 5 Wt.% precipitated silica, the melting and crystallization temperatures were significantly changed. The incorporation of 5 Wt.% precipitated silica and kaolin also enhanced the water vapor barrier properties of LDPE films. The light transmittance declined with the precipitated silica and kaolin addition, especially in the ultraviolet (UV)-A/UV-B spectrum regions indicating an excellent UV light protection.

It was concluded that NC/acrylic resins coatings containing precipitated silica and kaolin exhibit improved thermal stability, UV and water vapor barrier properties and have the potential for use in packaging applications.