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Abstract: The versatility of the fiber reinforced composites has significantly replaced some of the sophisticated metal components in certain sectors of industries. The matrix could be altered to improve self‐properties via silane modifiers by forming chemical linkages with the matrix in harmony with the reinforcing agents. This research work is an endeavor to enhance the traits of Vinyl ester by scrutinizing the influence of silane chemical agents using Hexamethyldisiloxane (HMDS). The dispersion time and concentration of these chemicals in matrix were optimized and henceforth a natural reinforcement, Abaca fabric was incorporated to constitute Natural fiber composite via Vacuum Assisted Resin Transfer Molding (VARTM) technique. The effect of resin modification on mechanical, thermal, and physical properties of Vinyl ester/Abaca (VE/AF) composite was examined. HMDS resin modified composite showed an improvement in the mechanical and flame retardant properties when compared to the pristine composite due to the formation of siloxane bonding which is compatible with the functional groups of both the matrix and the fabric. FT‐IR and FESEM characterizations have showed imperative evidences to support the results. This investigation provides a channel for enhancing the properties of natural fiber composites via chemical modification technique. [ABSTRACT FROM AUTHOR]

Advances in nanotechnology have opened new doors to overcome the problems related to contaminated water by introducing photocatalytic nanomaterials. These materials can effectively degrade toxic contaminants, such as dyes and other organic pollutants, into harmless by-products such as carbon dioxide and water. Consequently, these photocatalytic nanomaterials have the potential to provide low-cost and environment-friendly alternatives to conventional water and wastewater treatment techniques. In this study, a nanocomposite of zinc oxide and graphene oxide was developed and evaluated for photocatalysis. This nanocomposite was characterized by XRD, FTIR, FESEM, Diffuse Reflectance Spectroscopy (DRS), TEM and UV-Vis spectrophotometer. The photocatalytic behavior of the nanocomposite was studied through the degradation of methyl orange under ultraviolet light. It is reported that the weight ratios of zinc oxide and graphene oxide do not considerably affect the photocatalytic performance, which gives this process more compositional flexibility. Moreover, hydrogen peroxide was used as an electron scavenger to increase the time-efficiency of the process. The photodegradation rate can be significantly improved (up to 24 times) with the addition of hydrogen peroxide, which increases the number of trapped electrons and generates more oxidizing species, consequently increasing the reaction rate. [ABSTRACT FROM AUTHOR]

This study aims to improve the efficiency of fixed-bed-type photocatalytic reactors by immobilizing maghemite photocatalytic nanoparticles on a porous nickel substrate by using autoclave method. The resulting three-dimensional maghemite-Ni photocatalyst (3DMNP) has been characterized by using SEM/EDS, XRD, FTIR, TGA, and DTA. The photocatalytic behavior of the 3DMNP has been studied through the degradation of methyl orange in ultraviolet light as well as natural sunlight. It has been reported that the prepared 3DMNP demonstrates an excellent photocatalytic activity in both UV light and sunlight and can also be easily recycled for at least three subsequent cycles. This improved photocatalytic performance can be attributed to the charge carrier separation caused by the presence of nickel. [ABSTRACT FROM AUTHOR]

There has been a considerable amount of research in the development of sustainable water treatment techniques capable of improving the quality of water. Unavailability of drinkable water is a crucial issue especially in regions where conventional drinking water treatment systems fail to eradicate aquatic pathogens, toxic metal ions and industrial waste. The research and development in this area have given rise to a new class of processes called advanced oxidation processes, particularly in the form of heterogeneous photocatalysis, which converts photon energy into chemical energy. Advances in nanotechnology have improved the ability to develop and specifically tailor the properties of photocatalytic materials used in this area. This paper discusses many of those photocatalytic nanomaterials, both metal-based and metal-free, which have been studied for water and waste water purification and treatment in recent years. It also discusses the design and performance of the recently studied photocatalytic reactors, along with the recent advancements in the visible-light photocatalysis. Additionally, the effects of the fundamental parameters such as temperature, pH, catalyst-loading and reaction time have also been reviewed. Moreover, different techniques that can increase the photocatalytic efficiency as well as recyclability have been systematically presented, followed by a discussion on the photocatalytic treatment of actual wastewater samples and the future challenges associated with it.