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Surface-patterned membranes are becoming increasingly attractive for reducing fouling in membrane processes for water treatment. In this review article, literature on simulations of physically surface-patterned membranes is reviewed, with emphasis on the various factors affecting their anti-fouling performance. Associated computational techniques, including computational fluid dynamics and Brownian dynamics, are discussed. Key parameters discussed in the literature include the dimensions of the membrane (height, width), the velocity and direction of the fluid flow, the size of the particles, and the pattern size (height, width, and pitch). The key observables are the shear stress and velocity streamlines at various points, especially the pattern apex and valley regions, with an un-patterned membrane as a point of comparison in studies. The review concludes that the pattern dimensions have the most significant influence on the anti-fouling performance. Also, the effect of particle size to membrane pattern ratio on the extent of particle deposition on the membrane (fouling activity) can be explained by understanding the shear stress distribution around the membrane. [ABSTRACT FROM AUTHOR]

Since waste materials are used to identify, individualize, and evaluate evidence like fingerprints, palmprints, footprints, etc. that are found at a crime scene, they have a substantial impact on the field of forensic science. Many waste powders have recently been employed in fingerprint recognition. Nanosheets made up of eggshells have been put forward as an application in friction ridge development. Eggshell is a biochemical substance made up of chemical compounds like calcium carbonate, which is considered as a waste product. For the formation of an eggshell nanosheet (ESN), shells are dried and crushed into a fine powder and to get this powder in the form of a nanosheet, the Ball milling technique is used. The synthesis of pure ESN is confirmed by Scanning Electron Microscopy (SEM) and X‐ray diffraction (XRD) techniques. The size of nanosheets ranged from 30 to 90 nm as shown in SEM images. Developed powder is then used for the application of fingerprint development and it provides excellent results on all porous, non‐porous, and semi‐porous surfaces. Thus, this newly synthesized ESN powder can be used as a significant powder method in latent fingerprint technology. [ABSTRACT FROM AUTHOR]

Membrane–based gas separation has become an important research field for sustainable energy and environmental applications. Gas separation is one of the key steps in refineries and other gas‐related industries. Over the last two decades, the research on extended porous organic and inorganic materials such as zeolites, metal–organic frameworks (MOFs), covalent–organic frameworks (COFs), and their hybrids has increased continuously. These materials have garnered significant interest due to their structural flexibility and pronounced porosity, which offer excellent potential for gas adsorption and separation processes in industrial settings. As such, this review has aimed to provide an in‐depth analysis of the recent developments in MOFs, COFs, and MOF–COF hybrid‐based membranes for gas separation, highlighting their potential for practical industrial applications. It also offers a comprehensive understanding of some of the most critical and advanced materials used in gas separation compared to common polymers. In addition, membranes' concepts, efficiency, and cost‐effectiveness are discussed in detail. [ABSTRACT FROM AUTHOR]

The study of microswimmers in viscoelastic fluids is important due to their essential role in many biological systems and various industrial and medical applications. This review article summarizes the behavior of microswimmers in complex viscoelastic fluids. Interestingly, both an increase or decrease in the speed and the power efficiency of microswimmers may be observed depending on the swimming pattern and the rheology of the polymeric fluid. First, it introduces the continuum frameworks for a complex fluid in which the microswimmers are present. This study briefly discusses how the reciprocal motion can propel a swimmer in a viscoelastic fluid contrary to the scallop theorem. This is followed by a section on different types of individual swimmers and their theoretical framework. A finite‐sized swimming sheet can show the resonance effect when relaxation time matches the characteristic time of the swimming. Lastly, progress on the topic of squirmers in the complex environment is presented, and it is seen that the interaction of the squirmer with the complex fluid is unpredictable. [ABSTRACT FROM AUTHOR]

The world is constantly challenged regarding managing environmental and ecological contamination due to human and industrial activities. This is because of the constant threat posed by pollution. Nowadays, membrane‐based technology is a growing field, making practically all the separation of foulant from wastewater possible. The membrane fouling resulting from the interaction between the foulant and the membrane surface presents a challenge for the technology in maintaining performance over extended periods of operation. As a result, there is a rising interest in research focusing mainly on creating patterned membrane surfaces that reduce fouling and effectively enhance the surface area. This article comprehensively overviews the most recent and cutting‐edge techniques that can be applied to modify and construct high‐performance patterned membranes suitable for ultrafiltration, microfiltration, nanofiltration, and reverse osmosis (UF, MF, NF, and RO) water purification processes. In this study, recent developments in membrane material are dissected, focusing on methods for improving surface chemistry, structure, and hydrodynamics, as well as the consequences of these characteristics on filtering performance. [ABSTRACT FROM AUTHOR]

To address the escalating demand for efficient CO 2 separation technologies, we introduce novel membranes utilizing natural polymer guar gum (GG), conjugate polymer (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) PEDOT:PSS, and bimetallic PdPt nanoparticles. Bimetallic PdPt nanoparticles were synthesized using the wet chemical method and characterized using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques. The morphologies, chemical bonds, functional groups, and mechanical properties of the fabricated membranes were characterized using various techniques. Through meticulous fabrication and characterization, the binary blended membranes demonstrated enhanced homogeneity and smoothness in their structure, attributed to the interaction between the polymers, and superior CO 2 permeability due to the amphiphilic nature of the PEDOT:PSS polymer. Gas separation experiments performed using H 2 , N 2 , and CO 2 gases confirmed that the 20% PEDOT:PSS/GG blended membranes showed the best performance with sufficient mechanical properties. Moreover, the results demonstrated an increase of 172% in CO 2 permeability and 138% in CO 2 /H 2 selectivity, respectively. Furthermore, integrating bimetallic PdPt nanoparticles provided an additional 197% increase in CO 2 /H 2 selectivity, owing to the unique catalytic activities of noble metal nanoparticles. The study not only underscores the transformative potential of polymer blending and noble metal engineering, but also highlights the significance of using natural polymers for sustainable environmental solutions.