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Elevating industries: Cloud computing's impact on industry-integrated IoT
[No abstract available] -
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. -
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. -
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. -
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. -
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. -
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. -
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. -
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 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 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. -
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Electrochemical Synthesis of Carbocyclic and Heterocyclic Motifs
Programmability has left its mark on every facet of business, with technology playing newlinean integral role. Social networking industry trends underscore technology s ubiquity in newlinenearly every business transaction. Traditional networks grapple with numerous challenges, rendering them ill-equipped to process and handle the demands of the modern newlinelandscape effectively. The lack of programming in these networks leads to stagnation, newlineinhibiting their ability to evolve or enhance performance. The advent of Software Defined Networks (SDN) has introduced increased flexibility into conventional networks, newlineopening avenues for creating innovative services. newlineSDN technology addresses challenges in large-scale networks, offering solutions for newlinehigh throughput, virtualization, fault detection, and load balancing, providing effective network management. The rapid expansion of network services and applications newlinein SDN environments demands sophisticated load-balancing solutions that adapt to newlinedynamic traffic patterns and varying service requirements. This study presents a pioneering algorithm, the Dynamic Load Balancing Algorithm (DLBA), which utilizes the newlineProgramming Protocol-independent Packet Processors (P4) language. The algorithm is newlinespecifically crafted to tackle the issues associated with optimizing traffic distribution in newlinethe data plane of SDN. newlineP4 programming language, recognized as one of the most robust languages, addresses newlinethe limitations of traditional networking, enhancing programmability and agility by newlinedistributing the load across the network. The research implements a novel quotDynamic newlineLoad Balancing Algorithmquot using the P4 language to instill dynamism and achieve load newlinebalance in large-scale networks. The P4-based implementation showcases dynamicity, scalability, flexibility, and adaptability. This research commences with thoroughly newlineexamining existing load-balancing algorithms implemented using the P4 language, followed by a comparative analysis between these algorithms and DLBA. -
Electrochemical sensors using conducting polymer/noble metal nanoparticle nanocomposites for the detection of various analytes: a review
Abstract: Conducting polymer/noble metal nanoparticle (CP/NMNP) composites have made a history of sorts since its inception in the field of electrochemical research, which resulted to be an impetus for scientists to indulge and explore the opportunities it can unleash. This review throws light on the synergic effects and the enhancement in the electrocatalytic activity on dispersing noble metal particles on conducting polymers. This review aids the readers to analyse the electrochemical sensing efficiency of CP/NMNP composites, and provides a platform for the researchers to engineer and develop CP/NMNP composite materials for electrochemical sensing. This work also draws the attention of the readers to the application of NMNP (Ag, Au, Pt, Pd, Ir, and Ru) dispersed on CPs [polyaniline (PANI), polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT)] and their composites with other materials like carbon nanotubes (CNTs), graphene, zeolites, and peptide nanotubes (PNTs) for sensing of various analytes. Graphic abstract: This review draws the attention of the readers to the application of NMNP (Ag, Au, Pt, Pd, Ir and Ru) dispersed on CPs (polyaniline (PANI), polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT)) and their composites with other materials like carbon nanotubes (CNTs), graphene, zeolites, and peptide nanotubes (PNTs) for sensing of various analytes.[Figure not available: see fulltext.]. 2021, Islamic Azad University. -
Electrochemical sensor based on PVP coated cobalt ferrite/graphite/PANI nanocomposite for the detection of hydrazine
In this study, we developed a multi-layered electrode as an efficient nanocomposite electrochemical sensor for detecting carcinogenic hydrazine in water. Nano-cobalt ferrite (CoFe2O4) was prepared using poly (vinylpyrrolidone) (PVP), mixed with an optimum quantity of graphite and pasted on a stainless-steel current collector. The nanocomposite was further hybridised by electrodepositing with polyaniline (PANI). The obtained composite was characterized using XRD, FTIR, SEM, and electrochemical techniques. XRD analysis shows the successful formation of composite from individual precursors. According to SEM, wrinkled and layered morphology for graphite and aggregate clusters for cobalt with spike or tubular structure for polyaniline were observed. When subjected to amperometry current, the prepared electrode showed different peaks for different concentrations of hydrazine, such as 1 ?M to 100 ?M. Cyclic voltammetry studies showed an increase in oxidation and reduction peaks. These studies will lead to a new platform for their potential applications in detecting toxic materials in real samples such as water, plastic bottle, water etc., 2023 The Author(s). Published by IOP Publishing Ltd. -
Electrochemical sensing of vitamin B6 using platinum nanoparticles decorated poly(2-aminothiazole)
Vitamin B6 (Vit B6), also known as pyridoxine, is pivotal in fundamental physiological and metabolic processes within the body. Insufficient levels of this essential nutrient may contribute to various health complications. We introduce an electrochemical sensor designed to determine Vit B6 levels precisely. This sensor is constructed through a two-step process: first, by modifying a bare carbon fiber paper electrode (CFP) with poly(2-aminothiazole) (PAT), and second, by electrodepositing platinum nanoparticles onto the modified electrode surface, giving the final working electrode- Pt/PAT/CFP. Electrochemical impedance spectroscopy (EIS) and Cyclic voltammetry (CV) were utilized to examine the electrochemical characteristics of the developed sensor. The characterization of the sensor was done through a range of analytical techniques, including X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and optical profilometric studies. Furthermore, we optimized the sensor's performance by assessing the impact of pH, scan rates, and analyte concentrations. The sensor showed a wide linear dynamic range of 5.0 nM80 M and a low detection limit of 0.054 M. We have successfully quantified Vit B6 levels in tablet formulations and dried palm date fruits. The outcomes of this study hold the promise of substantial progress in Vit B6 quantification, with far-reaching implications across pharmaceuticals, healthcare, and nutritional science. 2024 Elsevier B.V. -
Electrochemical sensing of vitamin B12 deficiency marker methylmalonic acid using PdAu-PPy tailored carbon fiber paper electrode
Vitamin B12 is very important for human metabolism and its deficiency can cause anemia and the production of large red blood cells. An increased concentration of methylmalonic acid (MMA) is detected much before the transformation of blood cells, which thereby is an early indicator for mild or serious Vitamin B12 deficiency. A simple electrochemical sensor based on PalladiumGold (PdAu) was developed by electrodeposition of PdAu nanoparticles on Polypyrrole (PPy) modified carbon fiber paper (CFP) electrode. The modified electrodes were characterized by High resolution transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electroanalytical techniques. Differential Pulse Voltammetric (DPV) studies have established that under optimum conditions, the developed sensor exhibits a broad linear dynamic range (4.01 pM - 52.5 nM) with a very low detection limit (1.32 pM). The proposed method was effectively applied in the non-enzymatic determination of MMA at an ultralow level in human blood serum and urine samples. The method displayed high selectivity toward MMA in the presence of other interfering substances. 2020 Elsevier B.V. -
Electrochemical Sensing of Formaldehyde in Fish Samples Using a Polydopamine-Modified Stainless Steel Electrode
Electrodeposited polydopamine (pDA) on a stainless steel substrate was developed for electrochemical sensing of formaldehyde in fish samples. Experimental conditions such as influence of scan rate, pH, and concentration were optimized. The pDA modified electrode was sensitive enough to detect formaldehyde at a potential of 0.8 V in an acidic aqueous solution. The lLinear dynamic range for the detection of formaldehyde was in the range of 0.43 to 1.60 ?m under optimal conditions. The detection and quantitation limits were found to be 0.14 and 0.43 ?m respectively. The method was effectively employed for the detection of formaldehyde in fish samples. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
Electrochemical performance of ZnxCo3-xO4/N-doped rGO nanocomposites for energy storage application
In this study, nanocomposites consisting of zinc-doped cobalt oxides with a spinel structure and nitrogen-doped reduced graphene oxide (ZnxCo3-xO4 (x = 0 and 1))/N-doped rGO) were synthesized using a solvothermal method. The synthesized materials were investigated using XRD, TEM, EDS, BET, Raman, and XPS for their phase formation, morphology, elemental composition, surface area, and chemical states. XRD analysis revealed that the metal oxides (Co3O4 and ZnCo2O4) present in the composites exhibited a single-phase cubic spinel structure, with a nanocrystalline nature and crystallite size ranging from 8 nm to 20 nm. Raman and TEM analyses revealed the co-existence of metal oxide nanoparticles and N-doped rGO phases in the composites. Electrodes were fabricated using the synthesized nanocomposite materials and subjected to electrochemical testing, including CV, GCD and EIS. The specific capacitiance (Cs) of samples determined to be 181 F/g and 234 F/g for CO/NrGO (Co3O4/N-doped rGO) and ZCO/NrGO (ZnCo2O4/N-doped rGO) nanocomposites, respectively, at lower current density (0.5 A/g). At all current densities, the CS of ZCO/NrGO nanocomposite electrode is observed to be higher than the CO/NrGO nanocomposite, probably due to structural defects and uniform anchoring of ZnCo2O4 particles over the layers of NrGO. The ZCO/NrGO composite electrode exhibits ?86 % capacitance retention after 3000 cycles. 2024 Elsevier B.V. -
Electrochemical non-enzymatic strategy with green synthesized Fe2O3CuO nanocomposite for detection of amiprofos-methyl herbicide in industrial effluents and soils
Iron oxide-Copper oxide nanoparticles composite (Fe2O3CuO NPs) was synthesized through a green phytosynthetic approach using Ocimum sanctum Linn (commonly known as Tulsi) leaf extract. The evaluation of electrocatalytic properties were evaluated by carrying out electrochemical detection of amiprofos-methyl (APM), an organophosphorus herbicide. It is moderately toxic to mammals and aquatic biodiversity and is considered to be an acetylcholinesterase inhibitor. The presence of specific natural phytochemicals such as eugenol, naringenin, apigenin, quercetin, and high amount of ascorbic acid in the aqueous extract of Ocimum sanctum Linn plant parts, has been widely used for the synthesis of various metallic nanoparticles where these compounds serve as reducing, stabilizing, and capping agents. The synthesized Fe2O3CuO NPs were characterized using scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction analysis (XRD), UVVis spectroscopy, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The modified electrode was electrochemically characterized by cyclic voltammetry and differential pulse voltammetry (DPV) techniques for the detection of APM. The electrochemical signals have increased by three folds in the detection of APM with Fe2O3CuO nanocomposite compared to the bare glassy carbon electrode. The electrochemical sensor showed a linear range of 0.05 to 30 g/mL with a limit of detection of 0.0065 g/mL. The developed electrochemical sensor was successfully applied for the detection of APM in different water and soil samples with recoveries ranging from 96.00?99.00%. The electrode showed good stability and reproducibility over a period of 10 days with a 95% of peak current than the former. The newly synthesized nanoparticles, thus, proved to be an interesting material for electrochemical and biological studies. 2023 The Authors