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In this paper, wool fibers are modified with titanate tetrabutyl by coating and grafting titanium dioxide (TiO₂) nanoparticles under low temperature hydrothermal conditions. Field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, thermal gravimetric analysis and diffuse reflectance spectroscopy are used as the characterization techniques. It is found that anatase TiO₂ nanocrystals with crystal sizes smaller than 10 nm can be synthesized and simultaneously grafted onto fiber surfaces. In comparison with pristine wool fibers, the thermal stability for the TiO₂-coated wool fibers is slightly changed. The ability to block ultraviolet radiation is improved. The volume density is slightly increased. The tensile properties are enhanced, while the crimp properties worsened. A photocatalytic degradation process of methylene blue dye and a decoloration rocess of chlorophyll are developed.

The titania (titanium dioxide) is one of the important functional additives in the photosensitive resin and encounters the problem of stabilization in the photosensitive resin for 3D printing. This study aims to achieve enhancement in stabilization by preparation of the polymerizable titania and in situ laser-induced crystallization during 3D printing.

A type of polymerizable titania (AAEM@TiO₂) was designed and prepared from tetrabutyl titanate (TBT) and 2-(acetoacetoxy)ethyl methacrylate (AAEM) via the sol–gel process, which was characterized by Fourier-transform infrared (FTIR) spectra, ultraviolet–visible (UV-Vis) spectra, surface bonding efficiency (SBE) and settling height (H). AAEM acted on both bonding to the titania and polymerization with the monomer in resin for stabilization. The polymerizable titania could be converted to the pigmented titania by means of laser-induced crystallization. The photosensitive resin was then formulated on the basis of optimization and used in a stereolithography apparatus (SLA) for 3D printing.

The stabilization effect of AAEM on TiO₂ was achieved and the mechanism of competition in the light-consuming reactions during photocuring was proposed. The ratio of n_AAEM/n_TBT in AAEM@TiO₂, the concentration of AAEM@TiO₂ and photoinitiator (PI) used in the photosensitive resin were optimized. The anatase crystal form was indicated by X-ray diffraction (XRD) and clustering of nanocrystals was revealed by scanning electron microscopy (SEM) after SLA 3D printing.

This investigation provides a novel method of pigmentation by preparation of the polymerizable titania and in situ laser-induced crystallization for SLA 3D printing.

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.

The purpose of this paper is to increase wear resistance of aluminum.

The authors have studied the ways to improve the tribological performance of aluminum by assembling stearic acid on aluminum coated by sol-gel-derived TiO₂ film. The samples were characterized by infrared spectroscopy, contact angle measurements and a macro friction and wear tester.

Enhanced wear resistance was clearly obtained after functionalization of TiO₂ film on aluminum by stearic acid.

The relevant results might be helpful for guiding the surface modification of aluminum devices in industrial applications.

The purpose of this paper is to improve the properties of metal nanoparticles which are easy to agglomerate and hard to disperse evenly, thus limiting the application of metal nanoparticles in grease. A novel technology was proposed for modifying metal oxide to improve the dispersibility of nanoparticles.

SA-TiO2 nanoparticles were synthesized using an in-situ esterification method followed by surface modification with stearic acid. The microstructure of the nanoparticles was characterized by scanning electron microscope, transmission electron microscope and Fourier transform infrared spectroscopy and their thermal stability was evaluated by thermogravimetric analyzer. The tribological properties of the SA-TiO2 nanoparticles as additives in lithium grease were evaluated with a four-ball tester and TE77 reciprocating friction tester. The worn surfaces of the steel balls were investigated by EDS and XPS.

The prepared nanoparticles can be well dispersed in the lithium grease and possess much better tribological properties compared to traditional nanoparticles. The results indicated that the excellent tribological performance of SA-TiO2 was attributed to the chemical reaction film composing of Fe2O3, iron oxide and other organic compounds.

This paper provides a method to prevent the agglomeration of nano-TiO2 by surface modification with stearic acid. And the prepared nanoparticles can effectively improve the tribology performance of lithium grease.

This paper aims to improve the anti-corrosive properties of aluminum alloy AA2024-T3 by coating of hybrid sol-gel coating incorporated with TiO₂ nanosheets and to investigate the effect of nanosheets’ size on the improvement of corrosion-resistant performance.

A series of hybrid sol-gel films incorporated with varying amounts of TiO2 nanosheets were developed to enhance the corrosion protection performance of the bare metal. Scanning electron microscopy, transmission electron microscopy and atomic force microscopy were used to investigate the structure and morphology of the coatings obtained. In addition, the corrosion-resistant properties of the coatings were evaluated using salt spray test and electrochemical impedance spectroscopy.

The corrosion current was as low as 9.55 × 10-4 µA/cm² and optimal positive corrosion potential reached −0.6 V when the size and loading amount of TiO₂ nanosheet were optimized, resulting in a remarkable improvement in anti-corrosive properties.

This work first investigates the effect of incorporation of TiO₂ nanoparticles on hybrid sol-gel coating on the improvement of anti-corrosive performance of aluminum alloy AA2024-T3.

The purpose of this paper is to study the corrosion resistance and the insulating characteristics of an environment‐friendly chromium‐free coating on electrical steel.

A water‐based semi‐inorganic environment‐friendly insulating coating on electrical steel was developed. The coating system of silane coupling agent and rare earth salt were used first in this coating to replace the chromate containing coating. In this study, it provided a successful combination of coating and passivation.

Several test results, such as insulating ability, corrosion resistance, adhesion strength and hardness, showed that the performance of the film complied fully with the industry standards, particularly excellent in its corrosion resistance and the maximum corrosion resistance (neutral salt‐spray test) time up to 20 h.

There have been few reports on the chromium‐free insulating coating on electrical steel, and described in the paper, this environment‐friendly insulating coating on electrical steel was found to be highly effective.

HIGH SOLIDS COATINGS Review Articles Without question, the major motivation for high solids coatings is government regulations. An interesting article which summarises what the coatings industry has done in order to meet air pollution regulations in the United States has been provided by Burger (Metal Finishing, July, 1982, p. 59). His list includes, in addition to high build and solventless coatings, electrodeposition, electrostatic powder coatings, Rule 66—acceptable solvent‐based coatings, and water‐borne coatings. Air pollution results not only from solvents but from the particulates released during surface preparation. Pollution due to surface preparation has been alleviated by the use of white water sandblasting, centrifugal and rotary blast cleaning blast cleaning with carbon dioxide pellets, improved ventilation air filters and safety equipment, plasma arc and laser cleaning, sonic cleaning, special chemical cleaning, and surface preparation and vacuum blasting. In addition, solvent recovery units have been utilised extensively in industrial coatings.

The use of natural rubber and synthetic rubber for application to tanks, vessels and pipes, etc., in order to provide an anti‐corrosion lining, has been firmly established and accepted in the chemical engineering and allied industries for very many years. At the present time, such linings are used very extensively and have undoubtedly proved their worth and reliability in spite of the advent of ‘plastics.’

The South African wool industry is integral to the country's agricultural sector, particularly sheep farming and wool production. Small-scale farmers play a vital role in this industry and contribute to employment and food security in rural communities. However, these farmers face numerous challenges, including a lack of funding, poor farming practices and difficulty selling their wool at fair prices. This study aims to address these challenges, the University of Free State launched a wool value chain project for small-scale farmers.

In this project, one of the studies conducted assessed the effectiveness of different detergents suitable for traditional wool scouring methods for small-scale farmers who lack access to sophisticated machinery. The investigation was conducted by scouring 160 wool samples using three different detergents and filtered water as a control. The wool samples were then evaluated for their cleanliness, brightness and fibre properties through a combination of scanning electron microscopy, spectrophotometry and statistical analysis at different scouring times (3, 10, 15 and 20 min, respectively).

The results showed that the combination of scouring time and the type of scouring solution used could significantly impact wool quality. It was found that using a combination of standard detergent or Woolwash as a scouring solution with a scouring time of 10–15 min resulted in the best outcome in terms of fibre property, wool colour and scouring loss.

This study demonstrated that traditional wool scouring methods could be an option for small-scale farmers and anyone who want to learn how to scour wool without expensive machinery to make wool products.