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The elevated rates of electromagnetic radiation pollution, resulting from the growing need for wireless communication systems and electronic gadgets, have sparked interest in creating shielding materials that are lightweight, flexible, non-corrosive, simply processable, and affordable. In this study, a collection of microcellular nanocomposites based on ethylene octane copolymer (EOC) were created utilizing Vulcan XC 72 conductive carbon black (VCB) by a dual mixing process involving both melt and solution mixing. A chemical blowing agent was utilized to induce the cellular architecture in the composite, resulting in its lightweight nature (maximum density of 0.65 g/cc). The composite foam, when loaded with 30 parts per hundred of volume (phr) of VCB, displays a conductive network and also achieves an electromagnetic interference (EMI) shielding efficiency of 23.2 decibels (dB), satisfying commercial requirements. Furthermore, the findings indicated that the composite's cellular structure significantly influences the absorption-dominated EMI shielding mechanism with an absorption rate of 89%-94% and a specific shielding effectiveness of 194 dB[cm.sup.2]/g within the frequency range of 8.2-12.4 GHz (X band). The foam composite also demonstrated as a thermal management system, with a maximum thermal conductivity of 0.3 W/mK. As a result, this lightweight, easily processable, electrical conductive EOC/VCB polymer composite foams are projected to be used as EMI shielding materials in electronics, cars, and packaging. Highlights * Fabrication of lightweight microcellular Carbon black-loaded EOC composite * Rheological, mechanical, and thermal properties of foam composites * The cell density filled composites reduces by the cellular foam structures * Carbon black pronouncedly enhanced the electrical conductivity of foam composite * An absorption-dominated shielding effectiveness with ultra-low reflection. KEYWORDS conductive carbon black, electrical conductivity, EMI shielding, ethylene-octene copolymer, microcellular foam, 1 | INTRODUCTION With 5G technology and the growing need for highspeed, compact, portable electronics, and communication devices, electromagnetic (EM) wave pollution has become a major issue. (1-3) Electronic devices [...]

Online teaching and learning as an electronically supported approach relies mainly on the Internet as the medium for knowledge transmission. The utmost efforts are being made so that learning will be possible, even during the time of the COVID-19 pandemic, while also maintaining academic integrity. In this paper, we discuss the major steps taken to foster the educational needs of chemistry students in India along with the major challenges faced by Indian teachers and learners. Transmission of education involves all-round and far-ranging development of the learners. This paper elaborates on how the activities being carried out in everyday classrooms could not be replicated efficiently in an online teaching--learning platform. Great attention was given to maintaining academic integrity; this was reflected in the process of moving instruction online.

The increasing demand for flexible and wearable energy storage devices, particularly in the field of 3D printed macrobatteries and microbatteries, necessitates extensive research worldwide. While lithium-based batteries have traditionally dominated in the electronics market, recent challenges such as lithium scarcity and uneven distribution on the earth's surface have driven up the costs and created an alarming situation. Therefore, there is a critical need to shift the focus towards the development of non-lithium-based technologies. This review underscores the urgency of advancing non-lithium-based low-cost technologies for 3D printed batteries, specially focusing on microbatteries. These microbatteries will play a pivotal role in on-board microelectronic applications, including but not limited to medical implants, hearing aids, wireless sensor networks, earbuds, wearable sensors, and IoT sensors. The freedom of electrode architectures provided by 3D printing enhances the potential for innovation in this field. Each section of this comprehensive review delves into the complex details of various non-lithium battery technologies, highlighting their unique materials and recent developments in components. By prioritizing the exploration and development of non-lithium alternatives, the scientific community can contribute to the creation of sustainable and cost-effective solutions for the ever-expanding landscape of microelectronic applications. [ABSTRACT FROM AUTHOR]

(C−X) bonds (X=C, N, O) are the main backbone for making different skeleton in the organic synthetic transformations. Among all the sustainable techniques, electro‐organic synthesis for C−X bond formation is the advanced tool as it offers a greener and more cost‐effective approach to chemical reactions by utilizing electrons as reagents. In this review, we want to explore the recent advancements in electrochemical C−O bond formation. The electrochemically driven C−O bond formation represents an emerging and exciting area of research. In this context, electrochemical techniques offers numerous advantages, including higher yields, cost‐efficient production, and simplified work‐up procedures. This method enables the continuous and consistent formation of C−O bonds in molecules, significantly enhancing overall reaction yields. Furthermore, both intramolecular and intermolecular C−O bond forming reaction provided valuable products of O‐containing acyclic/cyclic analogue. Hence, carbonyl (C=O), ether ‐O‐), and ester (‐COOR) functionalization in both cyclic/acyclic analogues have been prepared continuously via this innovative pathway. In this context, we want to discuss one‐decade electrochemical synthetic pathways of various C−O bond contains functional group in chronological manner. This review focused on all the synthetic aspects including mechanistic path and has also mentioned overall critical finding regarding the C−O bond formation via electrochemical pathways. [ABSTRACT FROM AUTHOR]

The work highlights the assessment of fruit freshness through the incorporation of a chemiresistive gas sensor and machine learning. For this purpose, SnO2 nanosheets were synthesized through a low-temperature hydrothermal route. The sensor device was fabricated by integrating a synthesized nanomaterial with interdigitated electrodes. Fruits, including apple, guava, grape, and orange, were taken for analysis, and associated emitted volatiles were considered as the freshness indicator. Fruit samples were stored at room temperature, and systematic sensing measurements were performed at different time intervals (0, 24, 48, and 72 h) to estimate the freshness level. Initially, the responses of the sensor attained from apple, guava, orange, and grape samples were 1.7, 2.5, 6.4, and 2.2, respectively. A neural network-based regression model was employed for the determination of storage duration of fruits in a quantitative manner. The model displayed notable success in prediction, with an average error of less than 10%. Thus, the approach has great potential to develop a smart sensor system to monitor fruit freshness with a real-time outlook. [ABSTRACT FROM AUTHOR]

Heterocyclic molecules exhibit significant importance as they possess pharmacological, biological, and industrial applications. Although several excellent synthetic routes have been established for heterocyclic molecules, sustainable synthetic procedures such as microwave, ultrasound, grinding, photochemical, and thermodynamic route maps are needed to be explored further. Furthermore, these techniques become more eco-compatible when they produce value-added products in the absence of solvent. The advantages of these methodologies are to generate a library of small molecules, which will eventually combine to form complex bioactive molecules. In this review, we have emphasized recent studies (2010 to 2022) on the solvent-free conditions of various heterocycles (N, O, S), which have been synthesized via oxidation, reduction, condensation, and conjugated reactions. In this literature survey, glimpses of methodologies with their advantages, mechanistic considerations, and limitations are highlighted. These sustainable, and economically feasible routes will pave the way for a revolutionary corridor in the near future. [ABSTRACT FROM AUTHOR]

Correction for 'Recent developments in the solvent-free synthesis of heterocycles' by Nilabrata Dey et al., New J. Chem., 2023, https://doi.org/10.1039/d3nj01991h. [ABSTRACT FROM AUTHOR]