3D-Printing to Mitigate COVID-19 Pandemic

3D-printing technology provided numerous contributions to the health sector during the recent Coronavirus disease 2019 (COVID-19) pandemic. Several of the 3D-printed medical devices like personal protection equipment (PPE), ventilators, specimen collectors, safety accessories, and isolation wards/ chambers were printed in a short time as demands for these were rising significantly. The review discusses some of these contributions of 3D-printing that helped to protect several lives during this health emergency. By enlisting some of the significant benefits of using the 3D-printing technique during an emergency over other conventional methods, this review claims that the former opens enormous possibilities in times of serious shortage of supply and exceeding demands. This review acknowledges the collaborative approaches adopted by individuals, entrepreneurs, academicians, and companies that helped in forming a global network for delivering 3D-printed medical/non-medical components, when other supply chains were disrupted. The collaboration of the 3D-printing technology with the global health community unfolds new and significant opportunities in the future.     

Crosslinked poly(vinyl alcohol) membrane as separator for domestic wastewater fed dual chambered microbial fuel cells

The use of Nafion as a proton exchange membrane in microbial fuel cells (MFCs) is expensive with operational issues like biofouling and fuel crossover limiting the practical application of the device to harvest energy from wastewaters. In this connection, a facile route is adapted to fabricate a Nafion-alternative membrane using poly(vinyl alcohol) (PVA) crosslinked with glutaraldehyde (GA) as a relatively low-cost, effective membrane for MFCs. The crosslinking of the PVA membrane resulted in a reduction in hydroxyl groups and the formation of the acetal ring and ether linkage demonstrated by controlled water uptake and swelling ratio with enhanced thermo-mechanical stability. The crosslinked membrane displayed higher power density than those typically reported for domestic wastewater fed MFCs, reaching a maximum of 158.28 mW/m² for the fabricated membrane. The PVA-GA membrane with antimicrobial activity, high power performance, and negligible fuel crossover shows its potential as a separator in future MFCs based on its performance and low cost of installation.     

Perspectives of quantum computing for chemical engineering

Quantum computing has been attracting public attention recently. This interest is driven by the advancements in hardware, software, and algorithms required for its successful usage and the promise that it entails the potential acceleration of computational tasks compared to classical computing. This perspective article presents a short review on quantum computing, how this computational approach solves problems, and three fields that quantum computing can potentially impact the most while relevant to chemical engineering: computational chemistry, optimization, and machine learning. Here, we present a series of chemical engineering applications, the developments, potential improvements with respect to classical computing, and challenges that quantum computing faces for each of these fields. This article intends to provide a clear picture of the challenges and potential advantages that quantum technology may yield for chemical engineering, together with an invitation for our colleagues to join us in the adoption and development of quantum computing.     

Investigation of optical and thermally stimulated properties of SiO2 nanoparticles‐filled polycarbonate

Polycarbonate nanocomposite containing silicon oxide nanoparticles average size of 5 nm at different weight ratio has been prepared by solution mixing method. The dispersion of nanoparticles in polymer matrix was studied by transmission electron microscopy (TEM). The optical and thermally stimulated behavior of nanocomposites were analyzed by energy dispersive X‐ray spectra (EDX), X‐ray diffraction pattern (XRD), UV–vis spectroscopy, differential scanning calorimetry (DSC), and thermally stimulated discharge current (TSDC). TEM images show the dispersion and size of the nanoparticles, however, EDX indicate the presence of SiO₂ on the surface of the nanocomposite film. An XRD result reveals that the crystallinity increases with increase in concentration of SiO₂ nanoparticles in polymer matrix. The direct and indirect optical energy band gaps decreased and number of carbon atom increased with concentration of SiO₂ nanoparticles. We have observed that the increase of SiO₂ nanoparticles in PC significantly reduces the refractive index. DSC and TSDC show that glass transition temperature increases according to SiO₂ weight ratio. The TSDC of nanocomposites samples could be understand in terms of non‐Debye theory of charge relaxation and co‐tunneling mechanism of charge transport. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for C–C coupling and electrocatalytic application

The current work describes the synthesis of a new bio-waste derived cellulosic-carbon supported-palladium nanoparticles enriched magnetic nanocatalyst (Pd/Fe₃O₄@C) using a simple multi-step process under aerobic conditions. Under mild reaction conditions, the Pd/Fe₃O₄@C magnetic nanocatalyst demonstrated excellent catalytic activity in the Hiyama cross-coupling reaction for a variety of substrates. Also, the Pd/Fe₃O₄@C magnetic nanocatalyst exhibited excellent catalytic activity up to five recycles without significant catalytic activity loss in the Hiyama cross-coupling reaction. Also, we explored the use of Pd/Fe₃O₄@C magnetic nanocatalyst as an electrocatalyst for hydrogen evolution reaction. Interestingly, the Pd/Fe₃O₄@C magnetic nanocatalyst exhibited better electrochemical activity compared to bare carbon and magnetite (Fe₃O₄ nanoparticles) with an overpotential of 293 mV at a current density of 10 mA·cm^–2.     

Effect of Cold Rolling and Heat Treatment on Microstructure and Mechanical Properties of Ti-4Al-1Mn Titanium Alloy

Mechanical behavior of Ti-4Al-1Mn titanium alloy has been studied in annealed, cold-rolled and heat-treated conditions. Room temperature tensile strength as well as % elongation has been found to be low with increasing amount of cold rolling. Lowering of strength in cold worked condition is attributed to premature failure. However, the same has been mitigated after heat treatment. Significant effect of cooling media (air and water) from heat treatment temperature on microstructure was not found except for the degree of fineness of α plates. Optimum properties (strength as well as ductility) were exhibited by samples subjected to 15% cold rolling and heat treatment below β transus temperature, which can be attributed to presence of recrystallized microstructure. In cold worked condition, the microstructure shows fine fragmented α plates/Widmanstätten morphology with high dislocation density along with a large amount of strain fields and twinning, which gets transformed to recrystallized equiaxed microstructure and with plate-like morphology after near β heat treatment. Prior cold work is found to have a significant effect on mechanical properties supported by evolution of microstructure. Twinning is found to be assisting in deformation as well as in recrystallization through the formation of deformation and annealing twins during cold working and heat treatment. Fracture analysis of the tested sample with prior cold work and heat-treated condition revealed quasi-ductile failure as compared to only ductile failure features seen for samples heat treated without prior cold work.     

Characterization of copper nanoparticles synthesized by a novel microbiological method

The exploitation of various biomaterials for the biosynthesis of nanoparticles is considered as green technology as it does not involve any harmful chemicals. The present study reports the synthesis of copper nanoparticles which involves non-pathogenic bacterial strain Pseudomonas stutzeri, isolated from soil. These copper nanoparticles are further characterized for size and shape distributions by ultraviolet-visible spectroscopy, x-ray diffraction, and high resolution transmission electron microscopy techniques. The results showed that the particles are spherical and quite stable in nature and shows surface plasmon resonance clearly featured in the optical spectra in visible region.     

Iterative weighted EM and iterative weighted EM′-index for scientific assessment of scholars

Scientometrics - In the field of scientific assessment of scholars, there were several metrics has been given by the scholars. From the list of indices, the h-index is widely accepted for the...