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Portfolio Management Decision Support System Using Cryptocurrencies and Traditional Assets in Indian Context
The paper attempts to develop a portfolio management decision support system (PMDSS) to help the investors to ensure portfolio optimization in Indian context. For this, the study conducts a comparative analysis between portfolios with equities from Indian market and portfolios that includes cryptocurrencies along with equities. Considering the huge hype received by cryptocurrencies in the current scenario, we attempt to diversify portfolios by including risky assets like cryptocurrencies, specially focusing from Indian perspective. Till now, Portfolio Optimization with Monte Carlo Simulation and Hierarchical Risk Parity has not been implemented by combining portfolios of cryptocurrencies and Indian stocks together. Traditional assets for the study are selected upon their market capitalization, Earnings Per Share, Profit margin, Operating profit etc. and cryptocurrencies are chosen according to their market capitalization. Data on the daily prices of these assets are collected from 201920 to 202122. An attempt is made to optimize the portfolios by minimizing the portfolio standard deviation and maximizing the portfolio expected returns. This helps to minimize risk and maximize the possible returns that might arise from the portfolio after adjusting for the volatility of the asset classes respectively. Based on the results, we suggest not to incorporate cryptocurrencies in portfolios with Indian stocks. This is because the risk adjusted returns of cryptocurrencies are comparatively lower as compared to the other under study. The Author(s), under exclusive license to Springer Nature Switzerland AG 2024. -
Portable and Automated Healthcare Platform Integrated with IoT Technology
The diverse applications of Internet of Things (IoT), Artificial Intelligence (AI) in Bioelectronics - face recognition, pulse wave monitoring and insulin level measurements have been discussed in this chapter. This chapter also emphasizes on the IoT and its applications in biological sensors. The chapter focuses on IoT systems, such as neural networks and other channels that are integrated into a secure healthcare monitoring system in order to make the system operate as a smart model in healthcare sector that determines the priority based on health parameters gathered from the sensor nodes. In this work, the different approaches of IoT with distinct methodologies are also deliberated. 2024 Scrivener Publishing LLC. -
Porous medium convection in a chemically reacting ferrofluid with lower boundary subjected to constant heat flux
The effect of exothermic chemical reaction of zero-order on Bard-Darcy ferroconvection is investigated using the technique of small perturbation. The eigenvalues associated with an adiabatic lower wall are determined by employing the Galerkin method. The Darcy-Rayleigh number is computed in terms of the parameters pertaining to chemical reaction and ferromagnetic fluid. It is established that, when chemical reaction escalates, there is a considerable shift from linearity and occurrence of asymmetry in the basic temperature profiles. It is ascertained that the threshold of Bard-Darcy ferroconvection is augmented through the stresses of both mechanisms due to chemical reaction and magnetization, and the ferroconvective instability due to nonlinearity of magnetization is rather inconsequential when chemical reaction is present. It is also shown that the destabilizing feature of magnetic forces resulting from the fluid magnetization is less pronounced when chemical reaction is present. Published under licence by IOP Publishing Ltd. -
Porous carbons derived from Arecanut seeds by direct pyrolysis for efficient CO2 capture
In this report, we demonstrate the preparation of a series of carbon nanospheres (CNSs) with high surface area and tunable sizes from natural bioresource, Arecanut kernels, by using direct pyrolysis. This method offers a convenient approach to induce porosity in the synthesized carbons without the need for an activating agent. The textural parameters including the specific surface area, pore volume, and pore size can be controlled by the simple adjustment of the carbonization temperature from 700 to 1000C. The CNSs prepared at 700C showed a low specific surface area, whereas the higher carbonization temperatures (8001000C) supported the rise in specific surface area of the products (433.61001.4 m2/g). The carbon, hydrogen, and nitrogen (CHN) analysis revealed that the CNSs exhibited a high purity with the carbon percentage ranging between 96 and 99%. The synthesized materials were tested as adsorbents for CO2 gas, and it was found that the CNSs with the highest specific surface area of 1001.4 m2/g registered the CO2 adsorption capacity of 14.1 mmol/g at 0C and 30 bar, which is a reasonably high value among reported porous carbons prepared without activation. This value of CO2 adsorption also stands above the activated carbon and multiwalled carbon nanotubes. The excellent CO2 adsorption capability of these adsorbents along with their low-cost synthesis offers a feasible pathway for designing such materials for other applications as well. 2021, Qatar University and Springer Nature Switzerland AG. -
Porous carbon nanoparticles dispersed nematic liquid crystal: influence of the particle size on electro-optical and dielectric parameters
Porous carbon nanoparticles (PCNPs) of four different sizes (~180nm, ~51nm, ~41 and ~25nm) were dispersed into a nematic liquid crystal (NLC) in 0.25wt% concentration. PCNPs were derived from biowaste materials and pyrolysed at elevated temperatures to get the porous structure. Polarising optical microscopic observations were carried out in dark and bright states on both the pure NLC as well as NLC-PCNPs composites. Homogeneous alignment was well maintained in all the composites except the one with the highest sized (~180nm) PCNPs. Birefringence, relative permittivity and dielectric anisotropy, increases as the size of the PCNPs is decreased in the composites. The threshold voltage was also found to decrease with the decrease in the size of the PCNPs. Such investigations may be useful for the fabrication of display devices such as flat panel displays (FPDs) and phase shifters. 2021 Informa UK Limited, trading as Taylor & Francis Group. -
Porous 3D Printed System for Synergistic Tandem Water Cleaning-Energy Generation
Non-availability of fresh water is the dire consequence of rapid industrialization and the unregulated discharge of industrial effluents. In an attempt to recover water from highly contaminated industrial wastewater, researchers have relied on developing various materials that can treat polluted water efficiently and sustainably. 3D printed materials have proved to be an emerging technology in water treatment. 2Dmaterials have recently enhanced filter technology due to their morphological properties. This study focuses on removing salinity and organic dyes utilizing 2DGadolinium telluride (Gd2Te3) coated 3D printed (2D@3DP) complex architecture. The 2D@3DP structure can potentially increase the contact time of adsorbed saline water due to its complex architecture and can remove ?52% salinity from brackish water. Furthermore, methylene blue (MB) and Methyl Orange (MO) removal efficiencies are ?69% and 45%, respectively. Spectroscopic and microscopic results confirm the adsorption of negatively charged chlorine ions on a positively charged 2D surface. The removal of bleaching powder is also tested for real-life applications, and ?20% of the bleaching powder is adsorbed. Moreover, the 2D@3DP device exhibits an electrical signal due to impinging sodium chloride droplets from different heights, making it a sustainable solution to address water pollution. 2023 Wiley-VCH GmbH. -
Pore size matters!a critical review on the supercapacitive charge storage enhancement of biocarbonaceous materials
A circular economy targets zero waste converting both natural and synthetic wastes to valuable products, thereby promoting sustainable development. The porous nanocarbon synthesized from bio-waste is one such product used in applications such as energy storage, catalysis, and sensors. Different techniques are employed for synthesizing carbon from the biowastes and each route results in different properties toward end-user applications. Among them, surface area and porosity are the two critical factors that influence the energy storage capabilities of these synthesized carbon nanostructures. Besides the high surface area of the bio-derived carbons, the hindrance in supercapacitive performance is owing to its low porosity. Fewer review/research papers report the porosity tuning of these carbons for their influence on enhancing the performance of energy storage devices (supercapacitors). This critical review analyses the importance of porosity in these bio-derived carbons and reviews the recent development in its synthesis techniques along with its improvement in the energy storage capability. Special attention is also delivered to identify the ambient source of biowaste for carbon electrodes (fabrication) in supercapacitors. The recent research progress in tuning the porosity of these bio-derived carbons and the influence of electrolyte with porosity in affecting its supercapacitive energy storage is elucidated here. The research challenges, future research recommendations, and opportunities in the synthesis of bio-derived porous carbon for supercapacitor applications are briefed. 2022 Taylor & Francis Group, LLC. -
Populist Protests and the Dynamic Zero-COVID Policy: (Re)emerging Pragmatic Populism in China
Populist protests in the Peoples Republic of China (PRC) have recently emerged as a reaction against the Chinese authorities stringent measures under its dynamic zero-COVID policy. Besides the vehement criticism and protests against the dynamic zero-COVID policy, during some protests, there have been ensuing calls across the country for President Xi Jinping to step down. The article argues that this scenario can further deteriorate the overall political legitimacy of the Communist Party of China on a long-term basis. According to the article, the protests indicate the re-emergence of populism in the PRC, which incidentally and historically has parallels to the protests at Tiananmen Square, and the 1919 May Fourth Movement. The article theorizes John Deweys concept of pragmatic populism and the aspect of protests during the period, which inherently provides many ideational and relational facets with the recent protests in China. 2023 Jawaharlal Nehru University. -
Populism and the question of sovereignty in democracy with special reference to India
The sovereign manner of decision-making in a democracy is reckoned extremely crucial to stable governance. It is unfortunate, therefore, if the question of sovereignty acquires public attention predominantly in the wake of totalitarianist tendencies. It is the case now that with the emergence of several populist voices and nationalist sentiments, contemporary democracies actively debate the question of democratic sovereignty. This article is a critique of the complacency arising out of what is often wrongly perceived as the reassurances of the letter, or for that matter the spirit, of the constitutions of liberal democracies. Regardless of whether populism is traced within the electoral context or outside of it, the question of sovereignty offers a vantage point for understanding it from a theoretical perspective. In this regard, the article utilises the insightful yet contrasting notions of democratic sovereignty put forward by the philosophers Giorgio Agamben and Jacques Derrida. They approach the question of sovereignty from historical and/or linguistic points of view, illuminating the notions of sharing, sovereign violence and its overarching theological underpinnings. The articles findings, purposes and effects are meant to be educational and cultural in the first place. It employs, for the purpose of exemplification, a commentary on the Indian democratic scene. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024. -
Popularity Prediction of Online Social Media Content: A Bibliometric Analysis
An online social network is a platform that enables individuals to interact with others who have similar backgrounds, preferences, activities, and associations. The number of features available and the format of each online social network range widely. Users of online social networks, such as Twitter, Instagram, Flicker, and Pinterest, have increased dramatically in recent years. Content sharing is the most popular feature of online social networks, used by both specific users and big enterprises. This study has used bibliometric methods to analyze the growth of the social media popularity prediction on online social network content from 2013 to 2022. The publications have been extracted from the dimensions database, and the VOS viewer software was used to visualize research patterns. The finding provides valuable information on the publication year, authors, authors country, authors organizational affiliations, publishing journals, etc. Based on the findings of this analysis, researchers will be able to design their studies better and add more insights into their empirical studies. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Popularity of food blogs: Exploring the rationale /
Food blogs have been introduced to the world long years back. But it gained popularity only in recent years. It was considered as a leisure medium or as a hobby. The need for food blogs came into existence when people started to write about the food they ate or which they cooked. Most of the people who follow food blogs get attracted to the facts like the content, photographs, visual appeal etc. -
Polyvinyl alcohol and epoxy based composites for radition shielding applications
The present study has been focused towards designing efficient, non-toxic and cost-effective shielding materials with good mechanical strength for protection against radiations encountered in various environments like aerospace, hospitals, research and nuclear reactor establishments. From this perspective, to impart desired shielding properties, high Z filler dispersed polymer matrices such as Bi/WO3-polyvinyl alcohol (PVA), Ta2O5-epoxy, Ta2O5-Bi2O3-epoxy, micro Bi2O3-epoxy and nano Bi2O3-epoxy with varying filler contents have been synthesized. Structural characterizations were carried out using X-ray diffraction newline(XRD) and Fourier transform infrared (FT-IR) spectroscopy to reveal the interactions newlinebetween filler and polymer matrix. The morphological analyses were performed using newlinescanning electron microscopy (SEM) images. The AC conductivity measurements and newlineoptical studies revealed low conductivity property of the composites. The thermo newlinegravimetric analysis (TGA) and mechanical studies were conducted to ascertain thermal newlinestability and mechanical properties of the composites. With increase in filler concentration mechanical properties of Bi/WO3-PVA composites were found to be weakening. The TGA studies of Bi/WO3-PVA composites showed decrease in peak degradation temperature with increase in filler content. This prompted us to further design epoxy composites as epoxy matrix has good thermal stability and mechanical strength. Compared to neat epoxy, dispersion of varying wt% of Ta2O5 and Bi2O3 into epoxy matrix led to significant improvement in stiffness, storage modulus, glass transition temperature and thermal stability of the composites. Epoxy composites with 5 wt% of Ta2O5 and 30 wt% of Bi2O3 revealed better thermal and tensile properties when compared to same wt% Bi2O3 filled epoxy composites. The synergistic influence of micro and nano Bi2O3 filler on epoxy matrix composites showed similar thermal behaviour. -
Polyvinyl alcohol and epoxy based composites for radiation shielding applications
Extensive use of radioactive isotopes in medical fields, industries, and radiations in research and nuclear reactor establishments has increased the risk of exposure to directly and indirectly ionizing radiations. While charged particles such as beta, proton, alpha and heavy ions are directly ionizing radiations, X-rays and γ-rays are indirectly ionizing radiations. X-rays are often used to sterilize medical equipment and to treat cancer, while X-rays are used to provide static images of parts of the body such as teeth, bones, foreign substances within body, and are also used in industries to find fracture defects. According to the report by National Council on Radiation Protection and Measurements (NCRP, 2009), the use of ionizing radiations in medical field has drastically increased from 15% to 48% during 1980-2006. These radiations having sufficient energy interact with human body causing damage to living tissues. Though beneficial, prolonged exposure to these radiations can cause both somatic as well as genetic damage depending on time, distance and the type of radiation exposure. Hence, precautionary measures against the hazardous effects caused by these radiations have become a major concern in modern times. While exposure to radiations is inevitable, the radiation effects can be reduced by limiting the time of exposure, increasing the distance from radioactive source and using suitable shielding material. -
Polypyrrole/ silver/graphene ternary nanocomposite synthesis and study on photocatalytic property in degrading Congo red dye under visible light
In this report, a simple chemical synthesis of polypyrrole/silver/graphene (Ppy/Ag/Gr) ternary nanocomposites with varying concentrations of graphene are described. The XRD spectra of the samples polypyrrole/silver (Ppy/Ag) and Ppy/Ag/Gr show all the peaks of the face-centered cubic structure of silver. A broad peak between 10 and 20 and a peak at 26.7 corresponds to Ppy and graphene respectively. Using FTIR, and UVVis. spectroscopies the interaction between polypyrrole, silver, and graphene were studied. In our work, we explored the photocatalytic property of the synthesised samples by using them to degrade the aqueous solution of a cancer-causing dye, Congo red. The percentage degradation of Congo red dye using the sample Ppy/Ag/Gr (0.5 wt.%) is obtained as 96% and the reaction rate calculated is 0.162/min., greater than that of Ppy/Ag and Ppy/Gr binary composites. Thus, the addition of the optimum concentration of graphene into Ppy/Ag enhanced its photocatalytic property. The BET analysis shows an increased surface area for the sample Ppy/Ag/Gr (0.5 wt.%) and the reason for the enhancement of photocatalysis with this sample is confirmed since it is a surface-dependent property. The biodegradability of the dye solution was investigated by Chemical Oxygen Demand (COD) analysis and the COD value was reduced from 432 mg/L to 216 mg/L after 20 min of irradiation of light. 2023 -
Polypyrrole- silver nanocomposite for enhanced photocatalytic degradation of methylene blue under sunlight irradiation
Polypyrrole (Ppy) -Silver nanocomposite samples have been synthesised by chemical oxidative polymerisation. The characteristic peaks of face centered cubic (fcc) structure of silver in XRD confirmed its presence in Ppy. Shift in NH stretching frequency observed in FTIR spectroscopy revealed the coordination of silver into Ppy. The photocatalytic activity of the samples was studied by photocatalytic degradation of the aqueous solution of methylene blue (MB) under sunlight. The presence of Ag in polypyrrole (Ppy) enhanced its photocatalytic activity with respect to the reported values which further increased on increasing the silver concentration. 2021 Elsevier B.V. -
Polypyrrole functionalized MoS2 for sensitive and simultaneous determination of heavy metal ions in water
Assessing heavy metal ion (HMI) contamination to sustain drinking water hygiene is a challenge. Conventional approaches are appealing for the detection of HMIs but electrochemical approaches can resolve the limitations of these approaches, such as tedious sample preparation, high cost, time consuming and the need for trained professionals. Here, an electrochemical approach is developed using a nano-sphered polypyrrole (PPy) functionalized with MoS2 (PPy/MoS2) by square wave anodic stripping voltammetry for the detection of HMIs. The developed sensor can detect Pb2+ with a limit of detection of 0.03 nM and a sensitivity of 36.42 ?A nM?1. Additionally, the PPy/MoS2 sensor was employed for the simultaneous detection of HMIs of Cd2+, Pb2+, Cu2+ and Hg2+. The reproducibility, stability and anti-interference studies confirm that the sensor can be used to monitor HMI contamination of water. 2025 The Royal Society of Chemistry. -
Polyphenol composition and antioxidant activity of andrographis paniculata L. nees /
Mapana Journal of Sciences, Vol.13, Issue 4, pp.481-494, ISSN No: 0975-3303 (Print) -
Polyoxometalates and redox-active molecular clusters for supercapacitors
Hybrid electric vehicles and portable electronic devices become inevitable part of our daily life and it is necessary to develop efficient energy storage devices to supply them power. Supercapacitors (SCs) are electrochemical energy storage devices with high power densities. The electrochemical performances of a SC depend mainly on the electrode-active material used in it. An efficient electrode-active material should have qualities such as large surface area, porous structure, uniform pore distribution, good chemical and electrochemical stabilities, and good mechanical strength, to name a few. Mesoporous electrode architecture is highly preferred to obtain maximum electrolyte-ion accessibility that can boost the electrochemical performance of the SC electrode. The various electrode-active materials developed to date are transition metal oxides, electronically conducting polymers, carbon nanomaterials, etc. Polyoxometalates (POMs) are comparatively novel electrode candidates that possess excellent structural stability during the reversible redox reactions. A unique characteristic such as higher oxidation state possessed by POMs makes them an ideal platform to accept and release electrons during the electrochemical charge storage. POMs are considered to be a polyatomic anion, which hold early transition metals like Mo, V, W, etc., and are linked to an oxygen atom in a three-dimensional cluster. The cluster formation of POMs enables higher stability and easy to prepare composites with other materials such as carbon nanomaterial, electronically conducting polymers, etc. The preparation of hybrid electrode architectures by anchoring of POMs helps in producing a large number of electroactive sites for the enhanced electrochemical reactions to occur. This chapter explains the salient features and functionalities of POMs and redox-active molecular clusters that affect the SC performance. 2024 Elsevier Inc. All rights reserved. -
Polyoxometalate/?-Fe2O3/polyaniline composite: Tailored approaches for high-performance supercapacitors
The need for portable, high-performance electronics that have high power or energy density has increased significantly in recent years. In this work, a composite material was coated on stainless steel that consists of polyoxometalate (POM)/?-Fe2O3/polyaniline (PANI) as an electrode material for a symmetric supercapacitor. ?-Fe2O3 was prepared using starch as a template while PANI was electrodeposited. The physical and chemical characteristics of the modified electrodes were investigated via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and electrochemical techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge[sbnd]discharge (GCD) experiments. In 1 M H2SO4, the composite had a specific capacitance of 528 F/g at a current density of 0.2 A/g. In addition, the composite exhibited a high energy density of 73.4 Wh kg?1 at a high-power density of 7.14 kW kg?1 and 91.62 % capacity retention after 10 cycles. The results show that POM/?-Fe2O3/PANI is a promising composite electrode for use as a supercapacitor electrode material. 2024 The Authors -
Polynomial time learner for inferring subclasses of internal contextual grammars with local maximum selectors
Natural languages contain regular, context-free, and context-sensitive syntactic constructions, yet none of these classes of formal languages can be identified in the limit from positive examples. Mildly context-sensitive languages are capable to represent some context-sensitive constructions such as multiple agreement, crossed agreement, and duplication. These languages are important for natural language applications due to their expressiveness, and the fact that they are not fully context-sensitive. In this paper, we present a polynomial-time algorithm for inferring subclasses of internal contextual languages using positive examples only, namely strictly and k-uniform internal contextual languages with local maximum selectors which can contain mildly context-sensitive languages. 2017, Springer International Publishing AG.