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Electrochemical Synthesis of Heterocyclic Carbonyls Using Carbon Based Electrocatalysts
Electro-organic synthesis (EOS) is emerging as a powerful and sustainable technique newlinefor synthesizing organic compounds. EOS offers a compelling alternative to newlineconventional synthetic methods, driven by the need for cleaner and more efficient newlineprocesses and a growing focus on environmental impact. This approach minimizes newlineenvironmental impact by reducing dependence on hazardous chemicals and solvents. newlineAdditionally, EOS enables precise control over reaction parameters, leading to selective newlineproduct formation and potentially novel reaction pathways. newlineThis work presents the development of electrocatalysts for the electro-oxidation of newlineselected heterocyclic alcohols, namely piperonyl alcohol (PA), thiophene-2-ylmethanol newline(TM), furfuryl alcohol (FA) and indole-3-carbinol (IC) to their corresponding newlinealdehydes. A Toray carbon fiber paper (TCFP) substrate modified with 2D materials, newlineconducting polymers, metal oxides, and metal oxide nanoparticles are employed in newlinethefabrication of the electrodes. newlineThe efficiency of the developed electrode was studied employing different newlineelectrochemical and physicochemical studies. X-ray Diffraction Spectroscopy (XPS), newlineField Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray newlineSpectrometry (EDS), X-ray Photoelectron Spectroscopy (XPS), and Optical newlineProfilometry (OP) techniques were utilized for the physicochemical studies of the newlinefabricated electrodes. Cyclic voltammetry (CV), Electrochemical Impedance newlineSpectroscopy (EIS), Chronoamperometry (CA) and Bulk Electrolysis (BE) techniques newlinewere employed for the electrochemical studies, including optimization and synthesis of newlineheterocyclic aldehydes. The fabricated electrocatalysts demonstrated remarkable newlinestability, higher electrocatalytic activity, and good conductivity. The electro-oxidation newlinereactions were carried out in a three-electrode system via BE using 4-acetamido- newline2,2,6,6-tetramethylpiperidine 1-oxyl (4-ACT) mediator. The products obtained were newlinecharacterized by Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy. -
Electrochemical synthesis of nanoparticles
Nanomaterials possess diverse applications across environmental, medical, and energy sectors, owing to their unique properties dictated by structure, size, composition, and morphology. These characteristics of nanoparticles are pivotal in materials science. Their distinctive properties made an interest in specific applications, prompting the exploration of synthesis methods tailored for various purposes, particularly in electrochemistry. This chapter examines a nanoparticle synthesis technique capable of producing nanoparticles suitable for diverse applications, emphasizing electrochemical synthesis. This method offers efficient fabrication of nanoparticles at low temperatures with high purity, presenting an environmentally friendly preparation approach. Electrochemical synthesis, particularly through electrodeposition, involves the controlled passage of an electric current between the electrodes immersed in an electrolyte solution. This method yields stable nanoparticles with robust electrical contact, poised for utilization in batteries, fuel cells, supercapacitors, catalysis, optoelectronics, and beyond. The chapter elucidates the electrochemical synthesis process, underscoring its potential for advancing nanoparticle-based technologies across multiple disciplines. 2025 Elsevier Inc. All rights reserved. -
Electrochemical synthesis of ribonolactone-A precursor for anti-covid drug remdesivir /
Patent Number: 202141035480, Applicant: Dr B S Praveen Kumar.
The invention aims to create an energy use model for a chiller in heating, ventilation, and air conditioning system using the artificial neural network learning method. Input layers that included several input variables, quantity (percentage) of training data and number of neurons were measured for accuracy by the suggested chiller energy consumption model. A standard reference structure was also designed to provide operating data for the chiller system during long refrigeration periods (warm weather months). -
Electrochemical synthesis, photodegradation and antibacterial properties of PEG capped zinc oxide nanoparticles
The effect of surfactant and dopant on the properties of zinc oxide nanoparticles were studied by preparing polyethylene glycol (PEG) capped ZnO and tungsten doped PEG capped ZnO nanoparticles via the electrochemical method. These nanoparticles were characterized using X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet Diffuse Reflection Spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM) and Electron Dispersive Analysis of X Rays (EDAX). The photocatalytic degradation of malachite green dye using these nanoparticles was studied under visible light. The effects of various reaction parameters like dye concentration, catalyst concentration, pH and time were studied to optimize the photodegradation reaction. Reusability of these nanoparticles was studied and no significant change was observed in the degradation efficiency of PEG capped ZnO till the fourth cycle, while there was a gradual decrease in the degradation efficiency of tungsten doped PEG capped ZnO. Langmuir- Hinshelwood kinetic model well describes the photodegradation capacity and the degradation of malachite green follows pseudo-first order kinetics.Photocatalytic studies reveal that PEG capping increases the degradation properties of ZnO while tungsten doping decreases the extent of PEG capping and has a detrimental effect on the degradation properties of ZnO. The prepared nanoparticles exhibit significant antibacterial properties against gram-positive Bacillus cereus and gram-negative Escherichia coli bacterial strains by agar well diffusion method. 2018 Elsevier B.V. -
Electrochemical Transformation of Thiol-Iodine-Based Reactions toward Multiplexed Sensing Applications for Plant-Stress Hormone and Environmental Contaminant
Functionalized thiophenes are potential electroactive species that serve as efficient molecular electrochemical sensors. This work describes the fabrication of a 3-thiophene acetic acid (TAA)-modified screen-printed carbon electrode/multi-walled carbon nanotube (SPCE/MWCNT) platform via a facile electrochemical method in an aqueous medium. The effectual PT-Redox (product of TAA formed postpotentiostatic polarization) integration over SPCE/MWCNT was confirmed through various spectroscopic and electrochemical investigations. The SPCE/MWCNT showcased exceptional interaction with PT-Redox, creating a resilient platform for its precise binding, thereby enhancing the electrodeelectrolyte electroactive region, topographic roughness, electron conductivity, host response, and comprehensive electrochemical properties. The as-prepared electrode (SPCE/MWCNT@PT-Redox) was employed for the selective detection and quantification of glutathione (GT) as well as hydrazine (HyD) in an aqueous medium. The sensor showed excellent electrocatalytic oxidation responses toward these analytes, yielding a good sensitivity of 0.32 ?A mM1, a low detection limit (DL) of 0.225 ?M, a broad linear dynamic window of 0400 ?M for GT, a high sensitivity of 0.13 ?A mM1, a low DLof 0.56 ?M, and a linear window of 0350 ?M for HyD, obtained via the differential pulse voltammetry (DPV) technique. This substantiates that the modification with PT-Redox significantly boosted the electrodes interfacial activity and catalytic potential. Furthermore, the electrode exhibited robust antifouling and anti-interference traits, suggesting the composites enhanced stability and sensing capabilities for real-world applications. The captivating features, including excellent specificity, fast response dynamics, and simple sample preparation necessities of the proposed system, reveal a promising platform that accomplishes significant potential in futuristic sensing applications. 2025 American Chemical Society -
Electromagnetic Radiation-Driven Plastic Degradation and Energy Recovery for Sustainable Waste Management
The persistent accumulation of plastic waste presents a severe global environmental challenge. This study presents a non-thermal photodegradation and energy-recovery system that selectively cleaves 82 5% of CC/CH bonds in polyethene (PE), polypropylene (PP), and polystyrene (PS) within 30 min of UVC (254 nm) exposure. The bond-dissociation energy is harvested via thermoelectric generators (TEGs), delivering 10 W, and via photoelectric cells, yielding 5 W (10 mA.cm- at ? < 2 eV), for a combined recovery of 15 W. Emissions are held below 0.5 ppm VOCs and 0.1 mg.m- microplastics. A lab-scale prototype processes 0.5 kg.h-1 of mixed plastic per 0.1 m reaction area equivalent to 30 Wh.kg-1 of electrical energy and is scalable to 5 kg.h-1 in a pilot module. Real-time FTIR, Raman, and UV-VIS spectroscopy, integrated with an IoT-PID feedback loop, ensures autonomous optimization. Life-cycle assessment indicates a 25% reduction in greenhouse gas emissions compared to conventional recycling methods. A circular-economy framework envisions recovering oligomeric and monomeric fragments for direct reintegration into polymer production. Feature work will implement digital-twin simulations to refine process control, maximize throughput, and ensure long-term system reliability. 2026 by the authors Licensee: Technoscience Publications. -
Electron beam mediated synthesis of photoluminescent organosilicon nanoparticles in TX-100 micellar medium and their prospective applications
The inherent advantages of Silicon have made it as one of the most sought-after elements in the field of nanoscience and nanotechnology. Herein, we report an electron-beam induced formation of blue light emitting organosilicon nanoparticles (OSiNPs) in the micellar medium of Triton X-100 (TX-100). The profound role of the micellar medium can be realized from the enhanced colloidal stability as well as photoluminescence (PL) quantum efficiency (from ~9% to ~55%) of as synthesized OSiNPs. Mechanistic investigations revealed the crucial role of hydroxyl radical ([rad]OH) in the formation of OSiNPs. XPS and FTIR studies indicated the presence of siloxane/silicone and silica (SiO2) like units as the major constituents in the NPs. XRD pattern showed the amorphous nature of the NPs, while TEM studies revealed their aggregation. The hydrodynamic size of the NPs was determined to be ~24 nm. Interestingly, the NPs exhibited an excitation-wavelength-dependent PL behaviour, thereby indicating the presence of multiple emission centres (ECs). Detailed investigations based on steady-state as well as time-resolved PL measurements were conducted to analyse these ECs. In addition, pH and temperature-dependent studies were carried out to further substantiate these findings. Moreover, the experimental observations revealed their potential applications in the areas of thermosensing, fingerprinting and cell-imaging. Notably, the internalization of as prepared NPs within cells was evident from the bright fluorescence images obtained from the cytoplasmic region as compared to control cells. This observation also suggests the prospective application of these NPs for image guided drug delivery systems. 2021 Elsevier B.V. -
Electronic structure and intrinsic dielectric polarization of defect-engineered rutile TiO2
Experimental realization of colossal permittivity associated with intrinsic dielectric polarization of defect-engineered (Nb, In) co-doped rutile TiO2 appears to be most suitable for microelectronics and solid-state device applications. Combining resonant photoemission spectroscopy, X-ray absorption spectroscopy, and density functional theory calculations, we here present a coherent understanding of electronic structure, in-gap defect states, doped electron localization, and their connection with macroscopic polarization for various doping configurations. Most often, conventional sample preparation conditions introduce in-gap states of Ti3+? character, limiting the maximum achievable intrinsic polarization value. Our understanding provides a pathway to enhance intrinsic polarization and minimize dielectric loss through suitable defect-engineering. The Royal Society of Chemistry. -
Electronic Voting Systems Using a Blockchain-Based Encrypted Identity Management
The use of electronic voting technologies has grown in popularity as a way to make elections more secure and accessible. The implementation of blockchain-based encrypted identity management in electronic voting is explored in this study, which also offers a solid option to improve the reliability and credibility of voting systems. This study explores the possibilities for anonymous and transparent electronic voting while preserving voter privacy and anonymity by incorporating blockchain technology. It has always been challenging to create an electronic voting system that properly satisfies the requirements of administrators. This problem is now being resolved by blockchain technologies, which provide a distributed database with irreversible, encrypted identity management and secure transactions. A fascinating advancement in the realms of data innovation, dependability, and transparency is distributed ledger technology. Distributed ledger technology is commonly used in public blockchain. Virtually limitless potential for earning from sharing economies are provided by blockchain technology. This project aims to determine whether blockchain technology can be used to create electronic voting devices are used as a service. 2024 selection and editorial matter, Prof. (Dr.) Dorota Jelonek, Prof. (Dr.) Narendra Kumar, Prof. (Dr.) Mamta Chahar, Prof. (Dr.) Rusudan Kinkladze and Prof. (Dr.) Lilla Knop; individual chapters, the contributors. -
Electroreduction of CO2 to Methanol Using a Coordination-Moiety-Anchored Carbon-Based Electrode
Electrochemical reduction of carbon dioxide (CO2ER) has gained wide attention lately because of its potential to create a closed carbon loop, offering a sustainable solution toward environmental as well as energy crisis. However, the key challenge lies in the selective conversion of CO2 into electrofuels, such as methanol, which necessitates six proton-coupled electron transfers. In this work, we report the first instance of an electrochemically prepared Cu-coordinated 2,5-dimercapto-1,3,4-thiadiazole-modified carbon fiber paper electrode (CDM@CFP). The hence-engineered novel electrode was applied for the CO2ER reaction to produce methanol exclusively with an F.E. of 59.6% at a low potential of ?0.73 V versus RHE. Unlike most of the copper-based electrocatalysts, which result in multiple hydrocarbons, here, we have optimized a potential-dependent selectivity for maximum efficiency, which is a significant milestone in the field. 2025 American Chemical Society. -
Electrospinning of polyetheretherketone-based homopolymers and block copolymers
Electrospinning involves the fabrication of ultrafine fibers, typically ranging in diameter from nanometers to micrometers. This process entails applying a high voltage to a polymer solution or melt, resulting in the production of fibers that can be collected on a designated surface. Polyetheretherketone (PEEK) is a semicrystalline linear polycyclic aromatic polymer with high thermal stability. It is a high-performance thermoplastic known for its mechanical strength, thermal stability, and chemical resistance. The rigid radiolucency, stable physicochemical properties, and biocompatibility of electrospun PEEK homopolymer fibers make them suitable reinforcements in composite materials, medical sutures, removable prosthetics, vertebral surgery, orthopedics, and scaffolds for tissue engineering. PEEK homopolymers offer a wide range of advantages; however, they have a high melting temperature, high viscosity in the molten state, and a low glass transition temperature. Blending PEEK with other polymers and the formation of block copolymers introduces an additional set of functionalities by combining the properties of PEEK and other polymers. PEEK block copolymers can be electrospun with tailored properties and diverse morphologies, resulting in enhanced processability and compatibility for broad applications, including medical implants, filtration membranes, and reinforcing materials. This chapter discusses the principles and parameters of electrospinning, the factors responsible for the electrospinning of PEEK-based homopolymers and block copolymers, issues such as solubility, spinnability, and related costs, and possible solutions for overcoming these issues. Various applications of electrospun PEEK homopolymers and block copolymers are also discussed in this chapter. 2026 Elsevier Inc. All rights reserved. -
Electrospun nanofibers of 2D Cr2CTx MXene embedded in PVA for efficient electrocatalytic water splitting
The usage of transition metal carbide-based electrocatalysts has proven to be an efficient and effective strategy for enhancing the kinetics of water splitting reactions encompassing the generation of hydrogen (hydrogen evolution reaction, HER) and oxygen (oxygen evolution reaction, OER). In this investigation, we have prepared a composite material by integrating Cr2CTx MXene (derived from Cr2AlC MAX phase) and polyvinyl alcohol (PVA) through electrospinning technique. Carbonization of the MXene-PVA nanofibers resulted in the formation of Cr2CTx/carbon nanofiber (Cr2CTx/CNF) that exhibits high porosity, stability, surface area, and electrocatalytic activity. Systematic examination and optimization for the electrocatalytic water splitting reaction reveales outstanding performance, characterized by substantially lower overpotentials of 265 mV and 250 mV at the constant current density of 10 mA cm?2 with lower Tafel slope values of 85 mV dec?1 and 52 mV dec?1 for HER and OER, respectively. Moreover, this work presents a novel strategy for fabricating non-precious electrocatalyst Cr2CTx/CNF through a cost-effective and straightforward electrospinning and carbonization process, advancing electrocatalytic water splitting applications, especially for oxygen evolution reactions. 2024 The Royal Society of Chemistry. -
Electrospun PAN/TEMPO nanofiber electrode: Dual charge storage mechanism for supercapacitor applications
An advanced electrode material for asymmetric supercapacitors was created by electrospinning a polyacrylonitrile (PAN)/2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) composite. Strong interfacial interactions between the PAN chains and TEMPO nitroxide radicals were confirmed by Fourier transform infrared spectroscopy, which showed partial suppression of the PAN nitrile (C tbnd N) vibrations. X-ray diffraction revealed increased short-range molecular ordering of PAN caused by TEMPO via dipoledipole interactions, without changing the semicrystalline structure. In morphological studies, the incorporation of TEMPO showed decrease in the fiber diameter and enhanced surface roughness as compared to PAN fibers, resulting in the interconnected nanofibrous network with enhanced electrolyte accessibility. A mesoporous architecture with a quantifiable surface area and pore volume was characterized by BET analysis. A higher D-to-G band intensity ratio was found by Raman spectroscopy, which quantitatively indicated the formation of defects and improved electrochemically active sites in the PAN/TEMPO composite. The PAN/TEMPO electrode facilitates a dual charge storage mechanism that combines electrical double-layer capacitance from the nanofibrous PAN matrix and pseudocapacitance from reversible TEMPO redox activity due to these synergistic structural and chemical modifications. The assembled asymmetric supercapacitor exhibits a stable energy density of 7.71 Wh kg?1 and a power density of 365.33 W kg?1, and the composite electrode provides improved capacitive performance in acidic electrolyte. Additionally, Raman and EIS studies were performed for the PAN/TEMPO electrode after performing 5000 galvanostatic charge/discharge cycles to check the stability of the material. Overall, this work provides a novel approach to design supercapacitor electrodes with a structuredefectredox synergy in TEMPO-modified electrospun PAN nanofibers. 2026 The Authors -
Electrosynthesized Metal/Polymer Hybrid: Unlocking Selective Formate Production via CO2Electroreduction
Carbon dioxide reduction via electrochemical means offers a sustainable pathway to mitigate CO2emissions and synthesize value-added chemicals. Here, we report the synthesis and performance of a metal/polymer-carbon paper (CuxOy/PoPD/CFP) electrode prepared via a simple two-step in situ electrodeposition method for the electrochemical CO2reduction reaction (CO2ER). Unlike most reported catalysts that yield multiple liquid products and complicate downstream separation processes, CuxOy/PoPD/CFP selectively produces formate as the sole liquid product across all of the test potentials. The amine-rich and porous PoPD matrix synergistically enhanced CO2capture, provided a conductive scaffold for efficient electron transfer, and facilitated intimate interfacial contact with copper oxides, enabling improved catalytic performance. The catalyst demonstrated an onset potential of ??0.27 V (vs RHE) and achieved a faradaic efficiency of 72.6% for formate with a current density of 6.70 mA/cm2at ?0.80 V (vs RHE). Studies showcased an electrochemically active surface area (ECSA) of 16.625 cm2and a roughness factor of 8.31. The long-duration electrolysis experiment demonstrated stable performance for an extended period, maintaining continuous electrolysis for up to 9.5 h without significant fluctuations or degradation in activity. 2025 American Chemical Society -
Elemental abundances in the interstellar medium
One method to investigate the chemical composition of the interstellar medium (ISM) and interstellar dust grains is to conduct interstellar elemental depletion studies, especially of highly abundant species. The role refractory element, silicon (Si) in extinction is not clearly understood and the distribution and evolution of moderately volatile sulfur (S) in the ISM is still an open problem. The key motivation of the work is to investigatethe chemical composition of ISM of our Galaxy, and the formation, processing and distribution of interstellar dust in its different environments, mainly focusing on silicon and sulfur abundances, both in gas and dust.In the work outlined in this thesis, I will be describing the gas and dust phase abundances of Si and S in the interstellar medium using archival observations, and their probable role in the observed extinction. In this work, we also have measured the column density of S II along 9 Galactic sight lines using archival high-resolution observations from the Space Telescope Imaging Spectrograph and determined the abundances of S in both gas and dust phases. Using Archival spectral data towards 131 target stars in the Galaxy, interstellar Si abundances and depletion along those lines of sight has been surveyed. Oscillator strength correction has been performed to account for its improvements, using most recent values. This is an extensive survey done using a much larger data sample compared to previous investigations, but it substantiate the majority of the findings, which show that Si depletion is linked to both the average hydrogen density (n (H)) and the fraction of molecular hydrogen (f(H2)) along the lines of sight. -
Elemental Abundances in the Interstellar Medium
One method to investigate the chemical composition of the interstellar medium (ISM) and interstellar dust grains is to conduct interstellar elemental depletion studies, especially of highly abundant species. The role refractory element, silicon (Si) in extinction is not clearly understood and the distribution and evolution of moderately volatile sulfur (S) in the ISM is still an open problem. The key motivation of the work is to investigate the chemical composition of ISM of our Galaxy, and the formation, processing and distribution of interstellar dust in its different environments, mainly focusing on silicon and sulfur abundances, both in gas and dust. In the work outlined in this thesis, I will be describing the gas and dust phase abundances of Si and S in the interstellar medium using archival observations, and their probable role in the observed extinction. In this work, we also have measured the column density of S II along 9 Galactic sight lines using archival high-resolution observations from the Space Telescope Imaging Spectrograph and determined the abundances of S in both gas and dust phases. Using Archival spectral data towards 131 target stars in the Galaxy, interstellar Si abundances and depletion along those lines of sight has been surveyed. Oscillator strength correction has been performed to account for its improvements, using most recent values. This is an extensive survey done using a much larger data sample compared to previous investigations, but it substantiate the majority of the findings, which show that Si depletion is linked to both the average hydrogen density (n (H)) and the fraction of molecular hydrogen (f(H2)) along the lines of sight. Using this data, the distribution of Si and the variation of dust attributes with Si abundances also has been investigated and found that the linear component of the extinction curve is unrelated to depletion of silicon. -
Elementary Methods for Generating Three-Dimensional Coordinate Estimation and Image Reconstruction from Series of Two-Dimensional Images
The increase in computational power in recent years has opened a new door for image processing techniques. Three-dimensional object recognition, identification, pose estimation, and mapping are becoming popular. The need for real-world objects to be mapped into three-dimensional spatial representation is greatly increasing, especially considering the heap jump we obtained in the past decade in virtual reality and augmented reality. This paper discusses an algorithm to convert an array of captured images into estimated 3D coordinates of their external mappings. Elementary methods for generating three-dimensional models are also discussed. This framework will help the community in estimating three-dimensional coordinates of a convex-shaped object from a series of two-dimension images. The built model could be further processed for increasing the resemblance of the input object in terms of its shapes, contour, and texture. 2021 Naived George Eapen et al. -
Elementary Statistical Methods
This is the first book of two volumes covering the basics of statistical methods and analysis. Significant topics include concepts of research and data analysis, descriptive statistics, probability and distributions, correlation and regression, and statistical inference. The book includes useful examples and exercises as well as relevant case studies for proper implementation of the discussed tools. This book will be a valuable text for undergraduate students of statistics, management, economics, and psychology, wanting to gain basic understanding of statistics and the usage of its various concepts. The Editor(s) (if applicable) and The Author(s). under exclusive license to Springer Nature Singapore Pte Ltd. 2022. -
Elevating industries: Cloud computing's impact on industry-integrated IoT
[No abstract available] -
Elevating medical imaging: AI-driven computer vision for brain tumor analysis
Artificial Intelligence (AI) applications in the realm of computer vision have witnessed remarkable advancements, reshaping various industries and solving complex problems. In this context, this research focuses on the use of convolutional neural networks (CNNs) for classifying brain tumors - a crucial domain within medical imaging. Leveraging the power of CNNs, this research aimed to accurately classify brain tumor images into "No Tumor" and "Tumor" categories. The achieved test loss of 0.4554 and test accuracy of 75.89% exemplify the potential of AI-powered computer vision in healthcare. These results signify the significance of AI-driven image analysis in assisting healthcare professionals with early tumor detection and improved diagnostics, underlining the need for continuous refinement and validation to ensure its clinical effectiveness. This research adds to the expanding research and applications that harness AI and computer vision to enhance healthcare decisionmaking processes. 2024, IGI Global. All rights reserved.