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Ge-GaAs-Ge Heterojunction MOSFETs for Mixed-Signal Applications
A lattice matched heterojunction intraband tunnel (HJIBT) FET is proposed. The performance dependence of the device on conduction band (CB) discontinuity at source-channel and drain-channel interface is addressed using numerical simulation. Various mechanisms governing transport phenomena in the HJIBT FET are investigated in detail for different CB offsets (CBOs). For low gate to source voltage ( ${V}_{\text {GS}}$ ), thermionic emission is found to be the most significant transport mechanism. For moderate ${V}_{\text {GS}}$ , intraband tunneling phenomenon dominates over thermionic emission and continues to remain so. At high ${V}_{\text {GS}}$ , band-to-band tunneling occurs in HJIBT FETs. The proposed device shows improved figures of merit such as drain-induced barrier lowering (DIBL), ON-current ( ${I}_{ \mathrm{\scriptscriptstyle ON}}$ ) to OFF-current ( ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ ) ratio ( ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ), subthreshold slope (SS), gate capacitance ( ${C}_{\text {G}}$ ), ${g}_{m}$ (transconductance), and ${f}_{T}$ (cut-off frequency), with respect to conventional MOSFET. Also, the design of a high-performance hybrid 6T-static random access memory (SRAM) is proposed. 1963-2012 IEEE. -
Magneto-thermal-convection stability in an inclined cylindrical annulus filled with a molten metal
Purpose: Metal-cooled reactors generally use molten metals such as sodium, potassium or a combination of sodium and potassium because of their excellent heat transfer properties so that the reactor can operate at much lower pressures and higher temperatures. The purpose of this paper is to investigate the stability of natural convection in an inclined ring filled with molten potassium under the influence of a radial magnetism. Design/methodology/approach: A numerical simulation of electrically conductive fluid natural convection stability is performed on an inclined cylindrical annulus under the influence of a radial magnetism. The upper and lower walls are adiabatic, while the internal and external cylinders are kept at even temperatures. The equations governing this fluid system are solved numerically using finite volume method. The SIMPLER algorithm is used for pressure-speed coupling in the momentum equation. Findings: Numerical results for various effective parameters that solve the problem in the initial oscillatory state are discussed in terms of isobars, isotherms and flow lines in the annulus for a wide range of Hartmann numbers (0 ? Ha ? 80), inclination angles (0 ? ? ? 90) and radii ratios ? ? 6. The dependency stability diagrams between complicated situations with the critical value of the Rayleigh number RaCr and the corresponding frequency FrCr are established on the basis of the numeric data of this investigation. The angle of inclination and the radii ratio of the annulus have a significant effect on the stabilization of the magneto-convective flux and show that the best stabilization of the natural oscillatory convection is obtained by the intensity of the strongest magnetic field, the high radii ratio and inclination of the annulus at ? = 30. Practical implications: This numerical model is selected for its various applications in technology and industry. Originality/value: To the best of the authors knowledge, the influence of the inclination of the cylindrical annulus (ring), with various radii ratio, on natural oscillatory convection under a radial magnetism has never been investigated. 2020, Emerald Publishing Limited. -
Heat transport of magnetized Newtonian nanoliquids in an annular space between porous vertical cylinders with discrete heat source
A numerical study of MHD natural convection in an upright porous cylindrical annulus filled with magnetized nanomaterial is made by using the specificity of nanoliquids to improve the phenomenon of heat transport. The upper and lower walls are thermally insulated, whereas the outer wall is kept at a lesser temperature. The finite volume method is used to treat the governing equations via computer code with Fortran programming. The results obtained are given for the values of the Rayleigh number between 103 and 106, aspect ratio Ar = 2, radii ratio ? = 2, Hartmann number (0 ? Ha ? 80), Darcy number (10?5 ? Da ? 10?2), porosity ratio (0.1 ? ? ?0.9), and the nanoparticles volume fraction (0 ? ? ? 0.1). The transferred thermal flux, in laminar natural convection, increases with the growth of the nanoparticle concentration, the Darcy number, the porosity, the Rayleigh number and, the length of the source. 2020 Elsevier Ltd -
Ternary Blended Geo-Polymer Concrete - A Review
The manufacturing of ordinary Portland cement produces carbon di oxide which is responsible for global warming. Geopolymer concrete in the field of construction leads to economic sustainability and reduces adverse effects on environment. Geopolymers are inorganic polymers obtained from chemical reaction between an alkaline activator's solution and an alumina-silicate material without using cement. Alkali activators are Homogeneous mixture consisting of two (NaOH and Na2SO3) or more chemicals in different proportions are highly corrosive and difficult to handle. There are still some limitations with respect to the alkaline activators in geopolymer concrete. To overcome ordinary portland cement, many wastes materials such as Silica-fume, GGBS, fly ash etc. have been used in recent studies to create eco-friendly cements by geo-polymerization reactions. Geopolymers are economic & good alternative construction material in making concrete This review paper briefly explains on previous literatures, properties, materials of geopolymer concrete, testing and practical applications of geopolymer concrete. Published under licence by IOP Publishing Ltd. -
Stability and statistical analysis on melting heat transfer in a hybrid nanofluid with thermal radiation effect
The dual solutions for the stagnation point flow in a cobaltCeO2/kerosene hybrid nanofluid with melting heat transfer and thermal radiation are analyzed. The partial differential equations are solved by the conversion of the partial differential equations into nonlinear ordinary differential equations by utilizing suitable scaling group transformations. Numerical solutions are obtained by employing the built-in function in the MATLAB software (bvp4c). Physically recoverable solutions are found employing stability analysis. The factor variables of interest (melting parameter, the nanoparticle volume fraction of cobalt and CeO2) are then further analyzed by utilizing the sensitivity analysis (based on the response surface methodology model) for heat transfer rate, as well as the skin friction coefficient. It is found that the heat transfer and skin friction tend to be significantly higher in a hybrid nanofluid due to the radiation and melting heat transfer. The lower branch is found to be unstable, whereas the upper branch is found to be stable. Also, the heat transfer rate and skin friction coefficient are found to be negatively sensitive toward the melting parameter. The model in this study can be applied for microscopic propulsion systems and the nano-electromechanical systems integrated with a nano-based system. IMechE 2021. -
Mechanical strength and impact resistance of hybrid fiber reinforced concrete with coconut and polypropylene fibers
This experimental study investigates the mechanical properties and resistance to impact of concrete reinforced with coconut fibers (CF) and polypropylene fibers (PPF). The fiber proportions were decided based on the results obtained from the tests on coconut fiber reinforced concrete (CFRC) and polypropylene fiber reinforced concrete (PPFRC), tested individually. PP fibers of 12 mm and 24 mm of 0.1%, 0.2%, and 0.3% of the volume of concrete were used in PPFRC. Coconut fibers having 50 mm and 75 mm of 0.2%, 0.3%, and 0.4% of the volume of concrete were used in CFRC. Based on test results, PPF (12 mm) and CF (50 mm) were selected for hybrid fiber reinforced concrete (HyFRC). By varying both PPF and CF content, three different proportions with a total fiber content of 0.2% and 0.3% of the volume of concrete were selected. The improvement in strength was observed to be maximum when the total fiber content in the hybrid fiber reinforced concrete was 0.3%. The increase in impact resistance of HyFRC was almost double that of individual FRC and three times that of plain concrete. 2022 -
"Forgotten Communities" understanding the Anglo Indian community through the monthly magazine " The Review" /
A community has its own traditions and practices that have been followed by ancestors for generations. The Anglo-Indian community in India has a marginal, ethnic and minority existence in the social, cultural and political arena. Fighting for survival since the British era the community has emerged with its own uniqueness while living in India. It is considered as one of the most minority of races in India. -
Phytonanotechnology for the Removal of Pollutants from the Contaminated Soil Environment
Over-consumption of chemically synthesized components aids country toward industrial revolution, which symbolizes for economic prosperity. On the other hand, industrial revolution is responsible for soil pollution, due to its toxic effluents. The main source of soil pollutants includes fertilizers, pesticides, untreated wastewater used for irrigation, land application of sewage sludge due to rich organic content, petroleum leakage and leaching from landfills, etc. The crops grown out of this contaminated soil make the plant to changes its nutritional valve, bioaccumulates the chemicals, and also hinder with its vigor. Studies proved that prevent measures should prioritize in minimizing the adverse effect on the environment. Use of Phyto-nanotechnology in wastewater treatment, as nano fertilizer, nanotechnology-based biocontrol agents, and other areas before the hazardous chemicals entering soil. Green synthesized nanoparticles assist as excellent bio remedial agents as they are rich in biomolecules like carbohydrates, proteins, lipids, and several enzymes also deter-mine its efficacy of action. Hence, this chapter highlights the various eco-friendly and inexpensive products or formulation used for removal of toxic and recalcitrant materials which are dreadfully risky to human health. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022. -
Green-synthesized nanoparticles and their therapeutic applications: A review
Antibiotic-resistant microorganisms are a rising issue when it comes to human health. Microbial pathogens that cause harmful infections are quickly becoming resistant to the antimicrobial action of traditional antibiotics. Nanotechnology, an innovative sector being an indispensable part of healthcare and research, has in-depth and extensive applications. Nano-compounds have been promising antimicrobial agents, anti-cancerous mediators, vehicles for drug delivery, formulations for functional foods, identification of pathogens, food and drug packaging industry, and many more. However, the chemical synthesis of nanoparticles (NPs) has certain drawbacks such as causing toxicity and other adverse effects. For more than a decade, the use of NPs that are conjugated or green-synthesized has gained popularity due to the two-fold action of metallic NPs mixed with biological sources. In contrast, NPs synthesized using plant or microbial extracts, conjugated with biologically active components, appear to be a safe alternative approach as they are environmentally friendly and cost-effective. Such environmentally safe techniques are referred to as "green nanotechnology"or "clean technology"and are feasible alternatives to chemical methods. Furthermore, NPs conjugated with natural biomolecules have improved bioavailability and have minimal side effects, as they are smaller in size and have higher permeability in addition to being reducing and stabilizing agents possessing excellent antioxidant activity. NPs serve as potential antimicrobial agents due to their affinity towards sulphur-rich amino acids, adhere to microbial cell walls by means of electrostatic attraction, and disrupt the cytoplasmic membrane along with the nucleic acid of microbes. They possess anticancer activity owing to oxidative stress, damage to cellular DNA, and lipid peroxidation. The green-synthesized NPs are thus a promising and safe alternative for healthcare therapeutic applications. 2023 the author(s), published by De Gruyter. -
Escitalopram treatment ameliorates chronic immobilization stress-induced depressive behavior and cognitive deficits by modulating BDNF expression in the hippocampus
Major depressive disorder (MDD) affects 21% of the global population. Chronic exposure to stressful situations may affect the onset, progression, and biochemical alterations underlying MDD and associated cognitive impairments. Patients exhibiting MDD are mainly treated with several antidepressants; one is escitalopram, a selective serotonin reuptake inhibitor. However, whether or not it mitigates chronic stress-induced cognitive deficits is unknown. The present study exposed rats to chronic immobilization stress (CIS) 2 hours/day for 10 days. Then, escitalopram (5 mg and 10 mg/kg i.p.) was administered for 14 days and subjected to the elevated plus maze, open field test, forced swim test, sucrose preference test, and radial arm maze task. A different set of animals were used to assess the vascular endothelial growth factor (VEGF), glial fibrillary acidic protein (GFAP), and brain derived neurotrophic factor (BDNF) levels in the hippocampus, frontal cortex, and amygdale. Our data suggest that escitalopram significantly protected CIS-induced spatial learning and memory deficits, behavioral depression, and anxiety. Furthermore, escitalopram (10 mg/kg) shows a remarkable recovery of dentate gyrus and hippocampal atrophy. In addition, the restoration of molecular markers BDNF, VEGF, and GFAP expression is also implicated in the neuroprotective mechanisms of escitalopram. Our results suggested that esciatlorpam restores cognitive impairments in stressed rats by regulating neurotrophic factors and astrocytic markers. 2024 Shilpa Borehalli Mayegowda et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). All Rights Reserved. -
Sustainability and green nanomaterials on nanotechnology-based sensors
Nanobiosensors multipurpose efficacy in various domains as next-generation device has set a revolutionary impact on the scientific technology. Green synthesized nanoparticles (NPs) have enhanced the properties of these nanobiosensors in commendable ways with remarked growth. The unique properties of NPs like optical, magnetic, electrochemical, physiochemical, mechanical, and good conductivity make them highly reliable and sensitive for conventional approaches to check minute concentrations. Quantum dots, nanotubes, and magnetic nanowires provide a novel signal transduction mechanism that helps to detect low level of pesticides, food contaminants, toxins, and metabolites. Various microbes have been documented for NPs such as Fusarium oxysporum, Alternata alternata, Trichoderma viride, Colletotrichum sp., F. oxysporum, Aspergillus orayzae, Aquaspirillum magnetotacticum, and Magnetospirillum magnetotacticum. It is used in sustainable agriculture or smart farming to aid plant growth in the form of sensor detector of plant metabolites, hormonal changes, ion concentration, volatiles and gas changes, etc., under physiological stress. Environmental remediation is carried out for analysis and quantification of contaminants like heavy metals, pesticides, fungicides, pathogens, etc. Nanobiosensors have a tremendous impact on food industry as a means of sensitive method for detecting pathogens and recognition of mycotoxins. While, medical applications detect glucose in diabetics, cancer diagnosis, detection of urinary tract infections, HIV-AIDS, disease-causing pathogens, antigen-antibody interaction, etc. 2024 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies. -
Environmental applications of microbial fuel cells
The world is facing an energy crisis for non-renewable resources for the last decade. Hence, there is a search for highly efficient energy transformation techniques which utilizes alternate renewable energy sources. One such renewable energy production technology is Microbial Fuel Cell (MFC) based on dynamic organisms like microbes. MFCs allow producing electricity using renewable organic waste through microbial cellular respiration, which helps in reducing the carbon footprint as well as the environmental pollution. MFCs can also be used in metal recovery by bio electrochemical recovery, because metal ions can be reduced and deposited on an electrode by bacteria, algae, yeasts, and fungi. Microbial carbon capture cells are advancements to MFC, where algal biomass provides oxygen for cathodic reduction in the cathodic chamber and is ideally considered as the plausible technologies to tackle the ever-increasing problem of global warming and increased CO2 concentration. The MFCs find application in environmental remediation with respect to harmful organic pollutants by neutralizing/degrading contaminated water and soil. The harmful organic pollutants that can be neutralized include organic dyes, pesticides, insecticides, antibiotics, phenolic nitro phenolic compounds, and many others. This gives a long-term solution for pollutant degradation that is also environmentally acceptable. MFC-based biosensors have recently emerged as the next-generation biosensing technique for environmental monitoring. 2022 by Nova Science Publishers, Inc. -
Marine microbial biopolymers and their applications
Marine environment has been an important surrounding in recent times for valuable resources such as bioactive polymers. Increasing environmental concerns and realizing the limitation of global petroleum resources, biopolymers has gained utmost importance. Highly abundant renewable biopolymers of different polysaccharides have been produced from microbes, clams, shrimps, etc., exhibiting varying biological activities. Among all these biopolymers, microbial biopolymers are the most promising substitute for the existing synthetic polymers. Microbial polymers are synthesized intracellularly and extracellularly for their cell functions and survival playing specific roles as reserve materials for energy conservation, symbiosis and osmotic adaptation, protective agents that can be extruded and used for various applications. These biopolymers have exceptional moisture and oxygen barrier characteristics in making films for use in food industries and medical aspects. Microbial biopolymers that have been used include the cellulose, levan, pullulans, xanthan, gellan, kefiran, Haloferax exopolysaccharides, Polyhydroxyalkanoates (PHAs), and poly-3-hydroxybutyrates. Marine bacteria such as Bacillus, Halomonas, Alteromonas, Planococcus, Pseudoalteromonas, Vibrio, Zoogloea, and Thermococcus are found to be hyperproducers for biopolymers. Due to their high quality, sustainability, long shelf life, and biodegradability, they have been receiving interest for innumerable biological activities such as antioxidants, antidiabetic, antiinflammatory, and antimicrobial actions. Microbial marine biopolymers with natural biological activity, structural functions can be tailored using genetic engineering to obtain newer biomaterials with novel functionalities. 2025 Elsevier Ltd. All rights reserved. -
Bionanomaterials in Environmental Protection
The advent of globalization with ongoing anthropogenic actions has increased the rate of contaminants worsening aquatic, soil, and air systems, with increasing concern throughout the world. The several problems posed by these pollutants have endangered the environment as well as humans, leading to the application tasks of various conventional methods options to remove the pollutants. However, these technologies are costlier, of long duration, increasing energy consumption and also leading to toxins production. Nanotechnology, a newer method, has created a significant role in solving specific qualitative and quantitative, environmental issues of treating air, water, and soil by detection and removal of pollutants. Nanoparticles (NP) are low-cost, less energy consuming, eco-friendly and have higher efficiency rates. Nanosorbent, nanofiltration, nanocatalytic, and nanosensors methods have been used for the treatment of waste waters, air, and pollutant detection. There are different physical and chemical treatment options that have been employed for the synthesis of NPs, such as microwave heating and ultrasound methods. However recent decades have emphasized the green synthesis involving plant extracts and microbial sources due to their sustainability. Green synthesized NPs have gained immense interest due to their simplicity and relatively high reproducibility. In view of their capabilities, bionanomaterials can be used for eliminating pollutants and toxins, helping to maintain and spread a greener and cleaner environment. 2025 selection and editorial matter, Shakeel Ahmed; individual chapters, the contributors. -
Heavy metal detection by nanotechnology-based sensors
One of the major pollutants in the milieu consists of heavy metals that remain nondegradable with extreme toxicity that accumulates in plants, animals, and humans leading to ill effects with long exposures. These heavy metals that are used in various fields like food, textile industries, agriculture, and medicine act as enzyme inhibitors not allowing the substrate to bind the enzymes. In lieu of it, biosensors have been an essential tool that help to monitor environmental pollutants, presence of various toxins and biohazardous microbial in the organic matter, and also biomolecules in diagnostic tools. Detection of heavy metal traces in environmental monitoring has a widespread application using biosensors with improvised sensitivity, selectivity, and simplicity. Further, the biosensor technology has advanced greatly with the ability of biosensing mechanism combined with the highly advanced technique with the world of nanofabricating enabled miniature biosensors. The sensitivity performance of biosensors has increased tremendously with nanotechnology as the nanoscale dimensions promote the critical analysis and detect to probe single biomolecules. Nevertheless, the major drawback relies on the study lacking the toxicity of nanoparticles (NPs) in atmosphere, lacking in automated service, miniature induced unreliable source, and integrating the nano-biosensors for reliable transduction signals from the devices. With the development of biosensors for online and offline analysis for their quantity and diversity they have been termed as biosensor uprising with the introduction of biosensors with enzyme, DNA-, immuno-, and whole cell-based with specific analytical detection. 2024 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies. -
Plant, Animal, and Microbial Sources of Dyes and Mordants
Synthetic dyes and mordants have been used by various industries, including food, cosmetics, textiles, and pharmaceuticals, for many decades. However, their potential hazards to the environment and human health, such as carcinogenicity and teratogenicity, have raised global concerns. In earlier decades, people used naturally extracted dyes and mordants from plants and insects for purposes like painting, dyeing clothes, and enhancing skin and hair, using substances like henna, turmeric, and saffron. However, chemically synthesized dyes quickly replaced natural dyes due to their easy availability and low cost. Currently, consumers are becoming more conscious of the use of synthetic dyes and their effects, which can cause allergies and toxicity. This has led to a resurgence of eco-friendly dyes and biocolors, which have gained importance. There has been advanced and increased development in utilizing naturally occurring bioresources to produce sustainable biocolors with multifunctional applications. Natural colors have not only increased their market value due to their aesthetic appeal but also for their various properties, including antibacterial, antiviral, anticancer, anti-inflammatory, and antioxidant effects. Indeed, biocolors derived from plants, animals, and microorganisms have better degradability and compatibility with the environment. These naturally occurring pigments need to be explored from various natural sources to meet the increasing global demand, using suitable techniques for their extraction. 2025 Apple Academic Press, Inc. -
Bionanomaterials in Food Applications and their Risk Assessment
Nanotechnology has increased impressively during the last decade for their diverse potential uses in food, environment, medical, sustainable energy and so forth. Nanomaterial synthesis by chemical methods has unintended properties on the ecological pollution and also effect on human welfare. To overcome these challenges green synthesized nanoparticles (NPs) has been used from plants and animals. The green synthesized NPs include gold (Au NPs), copper (Cu NPs), silver (AgNPs), iron and its oxides (Fe NPs). Abundant microbes and plants are used for the synthesizing NPs that are eco-friendly, cost effective and potentially safe. Further, these can be constructed using agri-food waste sources such as agricultural crops, fruits and vegetables, cereals, oil cakes, alcoholic beverages, and so forth, for synthesizing sustainable NPs, reducing environmental issues. These green synthesized metallic NPs needs to be further characterized for the synthesis, factors affecting the parameters and their potential applications in various fields with major challenges that needs to be researched such as toxicity and translational research. 2025 selection and editorial matter, Shakeel Ahmed; individual chapters, the contributors. -
Further results on induced graphoidal decomposition
Discrete Mathematics, Algorithms and applications Vol.5, No.1, ISSN No.1793-8317 -
Induced Graphoidal Decompositions in product Graphs
Journal of Discrete Mathematics Vol.2013, Article ID 892839 ISSN No. 2090-9845 -
Service learning as a pedagogical strategy: A case study on disability inclusion
Diversity and inclusion are the growing concerns of society and every organisation including higher educational institutions (HEIs) is designing strategies to ensure diversity equality and inclusion (DEI). To understand how students engage with the idea of disability and inclusion in education, this study explores the journey of undergraduate students with an organization for visually challenged students. This qualitative, descriptive study used interviews and focus group discussion (FGD) along with the analysis of chosen reflective journals. SL activities enabled students to reflect on the learning challenges faced by the visually challenged students as well as their caretakers. This also made them reflect on the larger academic environment at the higher education level and come up with suggestions to make the HEIs more inclusive for the visually challenged. This study emphasizes the nature of their engagement and the transformative aspects of the learning process that they experienced by focusing on the students' experiences and challenges. 2024, IGI Global. All rights reserved.