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Formulation of Nickel OxideGraphene Composite Ink and the Fabrication of Thin-Film Electrodes Using Direct Ink Writing
Nickel oxide (NiO) is a p-type material with a wide bandgap of 3.6 to 4eV, and graphene is a zero-bandgap material. When the two materials are combined to form a composite, their structural, optical, and electrical properties are enhanced. This work presents the formulation of nickel oxide (NiO)graphene composite ink (with ethylene glycol as a solvent) for the fabrication of thin-film electrodes using a direct ink writing technique. NiO is used in nanopowder form, which is prepared via a wet-chemical approach. NiO ink is prepared in three different concentrations of 40mg/ml (N1), 60mg/ml (N2), and 70mg/ml (N3). Graphene ink (G) is also prepared in concentrations of 0.5mg/ml (G1), 1mg/ml (G2), and 2mg/ml (G3). Among the pure NiO inks, it was observed that low resistance and uniform printing were obtained for N2. Therefore, N2 is mixed with different concentrations of graphene to form the composite ink, which is further printed on the substrates. The rheological properties of all the formulated inks are measured. An extrusion-based direct-write system is employed for printing the inks on a glass substrate. The printed samples are characterized before and after annealing at 250C for 2h. The resistance of the composite ink (N2G1) is decreased by 53% in comparison with the pure NiO ink (N2). As the conductivity of the composite ink thin film is in the range of M?, they could find application in the field of gas sensing and thermistors. The Minerals, Metals & Materials Society 2024. -
MATHEMATICAL MODEL OF NICKEL-GRAPHENE COMPOSITE INKS FOR JETTING PROPERTIES IN INKJET PRINTING
The droplet formation process in inkjet printing is studied numerically and verified through a simulation model. The droplet formation process decides the printing quality of the coating, and a mathematical model is developed to understand the complete process from droplet formation to detachment. The Navier-Stokes equation is used to mathematically derive the droplet radius (rnumerical). COMSOL multiphysics is used for simulation and the radius (rsimulation) is calculated from the droplet mass. The rnumerical and rsimulation are compared for inks containing nickel, graphene, and nickel-graphene composite ink it is observed that the composite ink radiuses have the lowest difference (rsimulation - rnumerical = 0.085 m). A droplet is formed at 1.47 mm from the nozzle inlet, for nickel-graphene ink, and after 1.5mm for other pristine inks. The results are verified through Z number, velocity profile, and droplet mass. The droplet formation observed from the velocity profile is earliest at 120 s. It is seen that a stable droplet is generated at 100s for nickel-graphene ink and at 200 s for individual inks. 2024 Faculty of Science, Universiti Malaya. All rights reserved. -
Direct ink writing of nickel oxide-based thin films for room temperature gas detection
The rapid industrial growth and increasing population have led to significant pollution and deterioration of the natural atmospheric environment. Major atmospheric pollutants include NO2 and CO2. Hence, it is imperative to develop NO2 and CO2 sensors for ambient conditions, that can be used in indoor air quality monitoring, breath analysis, food spoilage detection, etc. In the present study, two thin film nanocomposite (nickel oxide-graphene and nickel oxide-silver nanowires) gas sensors are fabricated using direct ink writing. The nano-composites are investigated for their structural, optical, and electrical properties. Later the nano-composite is deposited on the interdigitated electrode (IDE) pattern to form NO2 and CO2 sensors. The deposited films are then exposed to NO2 and CO2 gases separately and their response and recovery times are determined using a custom-built gas sensing setup. Nickel oxide-graphene provides a good response time and recovery time of 10 and 9 s, respectively for NO2, due to the higher electron affinity of graphene towards NO2. Nickel oxide-silver nanowire nano-composite is suited for CO2 gas because silver is an excellent electrocatalyst for CO2 by giving response and recovery times of 11 s each. This is the first report showcasing NiO nano-composites for NO2 and CO2 sensing at room temperature. 2025 Chinese Institute of Electronics. -
Simulation study of droplet formation in inkjet printing using ANSYS FLUENT
Flow simulations of jetting of inkjet drops are presented for water and ethylene glycol. In the inkjet printing process, droplet jetting behaviour is the deciding parameter for print quality. The multiphase volume of fluid (VOF) method is used because the interaction between two phases (air and liquid) is involved in the drop formation process. The commercial inkjet printer has a nozzle diameter of ~73.2?m. In this work, a simulation model of inkjet printer nozzles with different diameters 40?m, 60?m, and 80?m are developed using ANSYS FLUENT software. It is observed that when water is taken as solvent then the stable droplets are generated at 60?m nozzle diameter till 9?s because of its low viscosity. For higher diameter, the stamen formation is observed. Ethylene glycol stable droplets are achieved at 80?m nozzle diameter till 9?s because of their high viscosity (~10 times that of water). Along with the droplet formation, the sustainability of the droplet in the air before reaching the substrate is also important. The simulation model is an inexpensive, fast, and flexible alternative to study the ink characteristics of the real-world system without wasting resources. 2022 Institute of Physics Publishing. All rights reserved. -
Expressions of Women Survivors of Domestic Violence: Idioms of Distress
Domestic violence is prevalent worldwide; however, there are cultural differences in womens experiences of this phenomenon. This study used the concept of idioms of distress, to understand the impact of domestic violence on women survivors in India. A qualitative method was adopted, and semi-structured interviews were conducted with six women survivors of domestic violence. Using thematic network analysis, one global theme, four organizing themes and 19 basic themes emerged. The idioms of distress identified included, physiological idioms (such as aches and pains, nutritional deficiencies, reproductive), psychological idioms (such as depression, low self-confidence, change in aspirations and ambitions, mistrust, rumination) and behavioral idioms (such as crying, withdrawal, irritability, disturbed sleep). Of all the idioms, only nutritional deficiencies and the reproductive idioms were of concern to the survivors and their marital family. Implications for improving the screening of domestic violence are discussed based on the identified idioms and the responses toward them. 2019, National Academy of Psychology (NAOP) India. -
Applications of Classification and Recommendation Techniques to Analyze Soil Data and Water Using IOT
As we are moving to a computerized and scientific world, data becomes an intrinsic part of our life. Agriculture sector is still unorganized with regard to automation and data analytics. This task is accomplished through sensors, data mining and analysis. In this paper, we propose real-time sensors to detect the soil features and predict the suitable crop cultivation using trained dataset. This would help the farmers to predict the type of cultivation to be done depending on the soil features. Today, the farmer can understand what type of cultivation will be prepared in the soil. Also, people of the upcoming generation will be using that sensor, different plant can be make. The cost of cultivation can be improved. Water level of the soil can be easily predicted. Which type of plant will be produced in the different soil can be predicted. So, this new type of cultivation followed by the next generation also. This paper has presented an improved by the pH sensor, water level sensor. 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Smart Air Pollution Monitoring System Using Arduino Based on Wireless Sensor Networks
Impurity levels in air have risen throughout time as a result of several reasons, such as population expansion, increased automobile use, industry, and urbanization. All of these elements harm the health of individuals who are exposed to them, which has a detrimental effect on human well-being. We will create an air pollution monitoring system based on an IoT that uses a Internet server to track the air quality online in order to keep track of everything. An alert will sound when the level of harmful gases such CO2, smoking, alcohol, benzene, and NH3 is high enough or when the air quality drops below a specified threshold. The air quality will be displayed on the LCD in PPM. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Fostering Inclusion in Digital Marketplace: Vistas into the Online Shopping Experiences of Consumers with Visual Impairment in India
Online shopping has become increasingly prevalent in recent years, overshadowing traditional brick-and-mortar shopping. Research has tried to understand the online shopping experiences of various consumers. However, the online shopping experiences of consumers with visual impairment (CWV) gained less attention. This study captures the online shopping experiences of CWV by employing a phe-nomenological qualitative approach. Data was collected from CWV through semi-structured interviews. The sample size of this study was fifteen, and data was analyzed using NVivo14. The findings indicate a growing preference for online shopping among the CWV. The results explore the accessibility-related issues encountered by CWV and strategies employed to overcome them. Additionally, the paper underscores the benefits of independence and the impact of online shopping on the personal growth and well-being of CWV. The study provides insights to marketers to foster inclusion in the digital marketplace. This study helps marketers and other stakeholders to understand the online shopping experiences of CWV and ensures consumer well-being and inclusion. Copyright 2024 Greeshma Thadikaran, Sandeep Singh. Published by Vilnius University Press. -
Navigating the need for accessible labelling through the narratives of consumers with visual impairment in India
This study aims to understand the strategies consumers with visual impairment (CWV) use in acquiring product information and explores preferences for accessible labelling and its benefits. This study employed the qualitative approach of thematic analysis. A snowball sampling technique was used to recruit participants. Data were collected from CWV through semi-structured interviews. The sample size of this study was 12. The data were analysed using NVivo software. The study revealed three strategies used by CWV to obtain product information, namely reliance on caregivers, staff, and technology. However, all the strategies employed have multiple drawbacks. The study reported a high preference for accessible labelling in braille and quick response (QR) codes. Implementing a combination of braille labels and QR codes on product packages was the most beneficial strategy for CWV. The Implementation of accessible labels ensures inclusion in the marketplace. The Author(s) 2024. -
Assault on religion from modern behavioural and natural sciences
[No abstract available] -
Enzyme based bioelectrocatalysis over laccase immobilized poly-thiophene supported carbon fiber paper for the oxidation of D-ribofuranose to D-ribonolactone /
Molecular Catalysis, Vol.524, ISSN No: 2468-8231.
A modified electrode based on laccase immobilized poly-thiophene-3-carboxylic acid supported on carbon fiber paper was developed for the electrocatalytic oxidation of D-ribofuranose to otherwise difficult-to-access D-ribonolactone, a precursor for C-nucleoside based drug like Remdesivir. The electrochemical oxidation of D-ribofuranose was achieved by the TEMPO-mediated electrochemical process. The experimental parameters were optimized and validated using Design of Experiment (DoE) statistical tool indicating the concentration of TEMPO and stirring as important parameters in bulk electrolysis. -
Anchored ferrocene based heterogeneous electrocatalyst for the synthesis of benzimidazoles /
Electrochimica Acta, Vol.435, ISSN No: 0013-4686.
A facile and sustainable electrochemical synthetic strategy for phenyl <a href="https://www.sciencedirect.com/topics/chemistry/benzimidazole" title="Learn more about benzimidazoles from ScienceDirect's AI-generated Topic Pages" class="topic-link">benzimidazoles</a> has been developed using a ferrocene-based <a href="https://www.sciencedirect.com/topics/chemistry/electrocatalyst" title="Learn more about electrocatalyst from ScienceDirect's AI-generated Topic Pages" class="topic-link">electrocatalyst</a> anchored on Toray carbon paper (TCP) coated with conducting polymeric film. The developed electrode was used for the electrochemical dehydrogenative <a href="https://www.sciencedirect.com/topics/chemistry/cyclization-reaction" title="Learn more about cyclization reaction from ScienceDirect's AI-generated Topic Pages" class="topic-link">cyclization reaction</a> of </span><em>o</em><span>-phenylene <a href="https://www.sciencedirect.com/topics/chemistry/diamine" title="Learn more about diamine from ScienceDirect's AI-generated Topic Pages" class="topic-link">diamine</a> and <a href="https://www.sciencedirect.com/topics/chemistry/benzaldehyde" title="Learn more about benzaldehyde from ScienceDirect's AI-generated Topic Pages" class="topic-link">benzaldehyde</a> using lithium perchlorate/acetonitrile as electrolyte. The surface characteristic properties of the developed electrode were characterized by <a href="https://www.sciencedirect.com/topics/chemistry/field-emission-scanning-electron-microscopy" title="Learn more about FESEM from ScienceDirect's AI-generated Topic Pages" class="topic-link">FESEM</a>, Optical profilometer and X-ray photoelectron spectroscopy. </span> -
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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. -
An Insight into Photophysical Investigation of (E)-2-Fluoro-N-(1-(4-Nitrophenyl)Ethylidene)Benzohydrazide through Solvatochromism Approaches and Computational Studies
A fluoro-based Schiff base (E)-2-fluoro-N?-(1-(4-nitrophenyl)ethylidene)benzohydrazide (FNEB) has been synthesized from condensation of 2-fluorobenzohydrazide and 4?-nitroacetophenone catalyzed by glacial acetic acid with ethanol as the solvent. The dipole moment of FNEB in both the electronic states were found using different solvatochromic approaches such as Lippert-Mataga, Bakhshiev, Kawski-Chamma-Viallet, Reichardt and Bilot-Kawski. The experimental ground state dipole moment of FNEB was calculated using Guggenheim-Debye method and theoretical ground state dipole moment using Bilot-Kawski solvatochromic approach. The solvatochromic behavior of the Schiff base in different solvents was studied using absorption and emission spectra. Catalan and Kamlet-Abboud-Taft parameters were used from the multiple linear regression (MLR) analysis in order to study the solute-solvent interaction. The dipole moments were also calculated using Time Dependent-Density Functional Theory (TD-DFT). The chemical stability of FNEB was determined using computational and Cyclic Voltammetry by the use of obtained energy gap between the frontier orbitals. Using the frontier orbitals energy gap, global reactivity parameters were computed. Further, Light Harvesting efficiency was determined to comprehend the photovoltaic property of the Schiff base. 2019, Springer Science+Business Media, LLC, part of Springer Nature. -
Review - Electrochemical Strategies for Selective Fluorination of Organic Compounds
The conventional methods for carrying out fluorination of organic compounds are typically conducted using a pre-modified starting material, usually expensive and toxic reagents. In this regard, electrochemical fluorination has been recognized as a sustainable and scalable strategy. Electrofluorination has proven to be an environmentally benign, highly effective, and versatile platform for the synthesis of selective organofluorine compounds under mild conditions. This review provides an overview on the use of anodic electrochemical methods for vicinal difluorination, iodofluorination, fluoroalkynylation, fluorodecarboxylation, fluoro desulfurization, radiofluorination, and synthesis of fluorinated heterocycles. Modern advances in the field of electrochemical fluorination, such as ionic liquids mediated electrochemical fluorination, triethylammonium halides, mixed non-aqueous solvents, alkali-metal fluoride, and split-bipolar electrodes in the field of electrochemical fluorination are also discussed. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
The Renaissance of Electro-Organic Synthesis for the Difunctionalization of Alkenes and Alkynes: A Sustainable Approach
Electro-organic reactions are now considered as one of the most efficient and environmentally benign methodologies to synthesize highly functionalized motifs like difunctionalized unsaturated compounds from readily available substrates. Excellent regioselectivity, functional group tolerance and broad range of substrates are the main advantages of electrochemical difunctionalization reactions. Alkenes and alkynes readily accept radical or ionic derivatives which makes it vital precursors for the electrochemical synthesis of industrially relevant and biologically active molecules through difunctionalization. This review aims to provide the readers an excellent coverage of the different electrochemical difunctionalization of alkenes and alkynes such as 1,2-homodifunctionalization, 1,2-heterodifunctionalization, rearrangement, ipso-migration, cyclization and dehydrogenative annulation reactions. 2021 Wiley-VCH GmbH -
Enzyme based bioelectrocatalysis over laccase immobilized poly-thiophene supported carbon fiber paper for the oxidation of D-ribofuranose to D-ribonolactone
A modified electrode based on laccase immobilized poly-thiophene-3-carboxylic acid supported on carbon fiber paper was developed for the electrocatalytic oxidation of D-ribofuranose to otherwise difficult-to-access D-ribonolactone, a precursor for C-nucleoside based drug like Remdesivir. The electrochemical oxidation of D-ribofuranose was achieved by the TEMPO-mediated electrochemical process. The experimental parameters were optimized and validated using Design of Experiment (DoE) statistical tool indicating the concentration of TEMPO and stirring as important parameters in bulk electrolysis. The mechanism for the electrochemical oxidation of D-ribofuronose followed single electron anodic oxidation of TEMPO mediated by laccase to the corresponding oxoammonium nitrosonium species which was vital for the mediated electrochemical oxidation. The mechanism for the electrochemical oxidation was established using cyclic voltammetry and computational studies. The plausible interactions of laccase enzyme with TEMPO mediator were studied using molecular docking experiments. This facile method was successfully applied for the oxidation of D-ribofuranose to D-ribonolactone. 2022 -
Immobilized proline-based electro-organocatalyst for the synthesis of bis-?-diketone via Knoevenagel condensation reaction
In the quest for more sustainable chemical processes, we devised a technique using electro-organocatalysis to synthesize bis-?-diketone compounds via Knoevenagel condensation of benzaldehyde and dimedone. Our approach involves a modified electrode fabricated via anchoring L-proline onto a carbon fiber paper electrode supported by poly-3,4-diaminobenzoic acid (PDABA), which enhances efficiency in addition to the simple catalyst separation from the reaction mixture in heterogeneous catalysis. The electrochemical and surface topographical studies for the fabricated electrode were carried out, revealing high efficiency in comparison to the bare carbon fiber paper electrode. This electrochemical reaction operates under mild conditions utilizing lithium perchlorate and acetonitrile, yielding high amounts of the desired product. This study showcases a promising pathway for producing valuable organic compounds in an environmentally friendly manner, marking a significant stride forward in sustainable synthesis practices. 2024 Elsevier Ltd -
Anchored ferrocene based heterogeneous electrocatalyst for the synthesis of benzimidazoles
A facile and sustainable electrochemical synthetic strategy for phenyl benzimidazoles has been developed using a ferrocene-based electrocatalyst anchored on Toray carbon paper (TCP) coated with conducting polymeric film. The developed electrode was used for the electrochemical dehydrogenative cyclization reaction of o-phenylene diamine and benzaldehyde using lithium perchlorate/acetonitrile as electrolyte. The surface characteristic properties of the developed electrode were characterized by FESEM, Optical profilometer and X-ray photoelectron spectroscopy. Electron transfer mechanism of the anchored ferrocene-based electrocatalyst was thoroughly studied. To determine the efficacy of the catalyst, the electron transfer coefficient (0.5) and apparent rate constant 41.4 s?1 were determined. The cyclic voltammetry studies reveal that the electrochemical oxidation peak for the synthesis of benzimidazole occurs at 0.48 V. The formation of the product was confirmed by Gas chromatography and Nuclear Magnetic Resonance spectroscopy. A comparison chart is presented for the green metrics and sustainability of the present strategy with other electrochemical approach. 2022 Elsevier Ltd