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Study of X-Ray Intraday Variability of HBL Blazars Based on Observations Obtained with XMM-Newton
We present an extensive study on the X-ray intraday variability of 10 teraelectronvolt-emitting high synchrotron peaked blazars (HBLs): 1ES 0229+200, 1ES 0414+009, PKS 0548-322, 1ES 1101-232, 1H 1219+301, H 1426+428, Mrk 501, 1ES 1959+650, PKS 2005-489, and 1ES 2344+514 made with 25 XMM-Newton pointed observations during its operational period. Intraday variability has been estimated in three energy bands: soft (0.3-2 keV), hard (2-10 keV), and total (0.3-10 keV). Although seven out of 10 teraelectronvolt HBLs exhibited some intraday variability at 3? levels, no major variations exceeding 6% were detected. We explored the spectral properties of the sample by extracting the hardness ratio from the soft and hard bands; no significant variations in the hardness ratio were observed in any source. We performed power spectral density analyses on the variable light curves by fitting power laws, yielding slopes lying in the range of 1.11-2.93 for different HBLs. We briefly discuss possible emission mechanisms and carry out rough estimates for magnetic fields, electron Lorentz factors, and emission region sizes for seven of these HBLs. 2022. The Author(s). Published by the American Astronomical Society. -
Effective Techniques Non-linear Dynamic Model Calibration using CNN
This paper proposes an efficient method to estimate nonlinear dynamic models using convolutional neural networks (CNNs). The proposed method combines the power of statistical optimization and machine learning to obtain more accurate and efficient estimates of complex models by training CNNs to recognize maps featuring input models and between results, thereby reducing the computational cost of measurements and then using the trained CNN to generate surrogate models -The method can determine accuracy for a range of exposed cases in various nonlinear dynamic models, including differential equation model of chemical reactor and stochastic model of biological systems The results show that the proposed methods are effective for measuring these models, if at most with such accuracy and reducing the computational cost in terms of both frequency and magnitude, the proposed method represents a promising method for estimating nonlinear dynamic models, offering significant advantages in terms of accuracy, efficiency and in scalability 2024 IEEE. -
Applications of artificial intelligence techniques in modern banking sectors
AI-powered decision-making instruments are cutting-edge technology that has the potential to displace conventional banking procedures. This chapter emphasizes the critical role artificial intelligence (AI) has played in guiding the banking industry toward expansion. AI techniques including robotics, deep learning, facial recognition, natural language processing, and more are used to achieve this goal. This chapter provides an overview of the use of AI approaches in several banking functional domains, such as loan approval, customer lifecycle management, customer services, alarm systems, and so on. It also highlights the benefits and difficulties that AI-driven financial apps provide. In summary, artificial intelligence (AI) has enormous promise in banking, but it also confronts several obstacles that, if correctly recognized and overcome, might broaden its use. This chapter is an invaluable tool for researchers, lawmakers, and bank officials who want to learn more about the unrealized potential of artificial intelligence in banking. 2024, IGI Global. All rights reserved. -
UVIT Observations of the Small Magellanic Cloud: Point-source Catalog
Three fields in the outskirts of the Small Magellanic Cloud were observed by the UltraViolet Imaging Telescope (UVIT) on board AstroSat, between 2017 December 31 and 2018 January 1. The observations were carried out on a total of seven filters, three in the far-ultraviolet (FUV; 1300-1800 band and four in the near-ultraviolet (NUV; 2000-3000 band. We carried out photometry of these observations that have a spatial resolution better than 1.?5. We present here the first results of this work, which is a matched catalog of 11,241 sources detected in three FUV and four NUV wavelengths. We make the catalog available online, which would be of use to the astronomical community to address a wide variety of astrophysical problems. We provide an expression to estimate the total count rate in the full point-spread function of UVIT that also incorporates the effect of saturation. 2023. The Author(s). Published by the American Astronomical Society. -
Molecular Simulation Prediction on SO2 Gas Adsorption in Bipyridine Ligand-Based Square-Pillared MOFs
Increasing concentrations of toxic gases caused by the burning of fossil fuels necessitates the development of efficient porous materials for gas capture. Metal-organic frameworks (MOFs) have attracted a lot of attention as potential porous materials due to their effectiveness in adsorption of toxic gases. In particular, square-pillared metal-organic frameworks stand out for their exceptional potential toward gas adsorption, attributed to their remarkable surface area, thermal and chemical stabilities, and tunable properties. In this context, molecular simulations have been executed to observe and analyze the adsorption process of toxic flue gases such as SO2 and CO2 on MOFs. The present work deals with two different stable fluorinated MOFs named [Ni(4,4?-bipyridine)2(AlF5)]n (ALFFIVE-Ni-bipy) and [Ni(4,4?-bipyridine)2(NbOF5)]n, (NBOFFIVE-Ni-bipy) featuring AlF52- and NbOF52- anion pillars, respectively, comprising 4,4?-bipyridine as organic ligand and nickel as the central metal. The significance of utilizing the 4,4?-bipyridine ligands in these fluorinated MOFs enhances the SO2 gas adsorption and selectivity in the framework. Density functional theory has been implemented for geometry optimization, and Grand Canonical Monte Carlo simulations have been performed to forecast the adsorption isotherms. Both ALFFIVE-Ni-bipy (11.4 mmol/g) and NBOFFIVE-Ni-bipy (8.7 mmol/g) showed high SO2 adsorption capacity at 1 bar pressure, but ALFFIVE-Ni-bipy showed very good adsorption than other square-pillared MOFs and also unveiled good selectivity of SO2 gas. The coadsorption of binary SO2/CO2 and ternary SO2/CO2/N2 gas mixtures at ambient conditions indicated that the cost-effective aluminum (Al)-based square-pillared ALFFIVE-Ni-bipy is particularly suitable for acid gas adsorption. 2024 American Chemical Society -
Discontinuities in the trajectory of solar photovoltaic (SPV) technology development in India
The objective of this paper is to understand different phases of solar photovoltaic (SPV) technology in India and the interplay of scientific, technological, economic, and political factors in each of the phases. There are four distinct phases. In the first-phase (1947-1970), SPV technology was recognized as an important source of energy for countries like India. In the second phase (1971-1990), the oil crisis led to the formulation of new scientific and technological initiatives and programs in SPV, but due to a lack of political commitment the initiatives disintegrated. In the third phase (1991-2003), several factors seemed to have undermined the development of SPV sector. Currently in the fourth phase (2003 to the present), India has virtually lost the race for development of photovoltaic technology. Within the context of climate change and resource constraint, India has reformulated its strategy which has taken the form of the Jawaharlal Nehru National Solar Mission Plan (JNNSM).This paper examines how JNNSM influences indigenous attempts in photovoltaic technology development. The paper shows how scientific, technological, economic and political factors have contributed to discontinuities in the development of the technology. Koninklijke Brill Nv, Leiden 2015. -
Performance Evaluation of OTFS Under Different Channel Conditions for LEO Satellite Downlink
Orthogonal Time Frequency Space (OTFS) modulation scheme is being actively pursued as a viable alternative to Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme in future wireless standards due to the inherent ability of OTFS to mitigate the Doppler effects in high mobility scenarios. The inclusion of Non Terrestrial Network (NTN) in Release 17 of 3GPP (3rd generation partnership project) New Radio (NR) standard signifies the vital role of Satellite Communications to achieve coverage extension, capability augmentation and seamless global connectivity. In this context, it becomes important to study the suitability of OTFS modulation scheme with respect to satellite channel scenarios. In this paper, we consider the downlink channel scenarios defined by 3GPP NR NTN for Low Earth Orbit (LEO) satellites at sub-6 GHz and millimetre wave frequencies for evaluating the performance of OTFS modulation schemes. Simulation results using LMMSE (Linear Minimum Mean Square Error) and MRC (Maximum Ratio Combining) detection algorithms confirm that OTFS modulation is highly robust against Doppler effects and performs consistently across all channel conditions. From simulation results, it is observed that the performance of iterative MRC detection is better than LMMSE for 16QAM and 64QAM modulation schemes by achieving respective gains of around 5 dB and 10 dB for corresponding Bit Error Rate (BER) values of 0.01 and 0.1. 2023 IEEE. -
ESIPT-AIE Active Schiff BaseFluorescent Organic Nanoparticles Based on 2-(2-(4-(4-bromo Phenyl) Thiazol-2-yl)Vinyl)Phenol (BTVP) Utilized as a Multi-Functional Fluorescent Probe
The present study reports the synthesis and characterization of Aggregation-Induced Emission (AIE) Excited-state intramolecular proton transfer (ESIPT) active 2-(2-(4-(4-bromo phenyl) thiazol-2-yl)vinyl)phenol (BTVP). The AIE properties of BTVP in Acetone/Water solution are investigated, and fluorescent organic nanoparticles (FONs) (sizes ranging from 150200nm) are preparedin various water fractions (fH2O). The established visco-chromic property suggests that the restriction of intramolecular rotation is responsible for the AIE-ESIPT behavior of the molecule, providing a means to sense viscosity. The synthesized FONs act as fluorescence chemosensors to detect Al3+ ions via a photoinduced electron transfer (PET) mechanism. Job's, BenesiHildebrand method, and 1HNMR titration confirm the 1:1 binding of BTVP with the metal ion. Studies on the emission concerning pH reveal the high stability of FONs over a broad range of pH, and a gradual change in the emission wavelength for the BTVP-Al3+ complex (BTVP-Al) is observed, providing a means to sense pH ranging from 28. The solid-state photoluminescence of BTVP is used for latent fingerprint detection, demonstrating its efficiency in detecting both primary and secondary information. Additionally, both BTVP FNOs and BTVP-Al are used in cell imaging, where specific nuclear staining with BTVP-Al and cytoplasm staining with BTVP are observed. 2023 Wiley-VCH GmbH. -
Synthesis, DFT and In Silico Anti-COVID Evaluation of Novel Tetrazole Analogues
A new series of 3-aryl/heteroaryl-2-(1H-tetrazol-5-yl) acrylamides have been synthesized through catalyst-free, one-pot cascade reactions, utilizing click chemistry approach and evaluated for their anti-COVID activities against two proteins in silico. The structural properties of the synthesized molecules were evaluated based on DFT calculations. Total energy of the synthesized tetrazole compounds were obtained through computational analysis which indicate the high stability of the synthesized compounds. The Frontier Molecular Orbitals (FMO) and associated energies and molecular electrostatic potential (MEP) surfaces were generated for the compounds. Spectral analysis by DFT gave additional evidence to the structural properties of the synthesized molecules. All tetrazole analogues come under good ADMET data as they followed the standard value for ADMET parameters. Docking studies offered evidence of the molecules displaying excellent biological properties as an anti-Covid drug. Compound 4 g exhibited excellent anti-COVID-19 properties with four hydrogen binding interactions with amino acids GLN 2.486 GLN 2.436 THR 2.186 and HSD 2.468 with good full-fitness score (1189.12) and DeltaG (7.19). Similarly, compound 4d shown potent activity against anti-COVID-19 mutant protein (PDB: 3K7H) with three hydrogen binding interactions, i.e., SER 2.274 GLU 1.758 and GLU 1.853 with full-fitness score of 786.60) and DeltaG (6.85). The result of these studies revealed that the compounds have the potential to become lead molecules in the drug discovery process. 2022 Taylor & Francis Group, LLC. -
A Selective Excited-State Intramolecular-Proton-Transfer (ESIPT) Sensor for Copper(II) Based on Chelation-Enhanced Quenching and Off-On Detection of Amino Acids
We report the synthesis of 2-(4,5-diphenyl-1H-imidazole-2-yl)phenol (TPI-9) as an interesting fluorescent molecule displaying Excited-State Intramolecular-Proton-Transfer (ESIPT) with stokes shift of 120 nm. Phenolic compounds with the ability to form intramolecular hydrogen bonds and subsequent proton transfer are known as ESIPT fluorophores. Proton accepting ability can increase significantly by tailoring electron-donating groups. With the assistance of an environment-friendly organocatalyst, 10-camphor sulfonic acid (10-CSA), TPI-9 was synthesized to introduce substituents with electron-donating abilities to develop an efficient ESIPT mechanism. Factors influencing the emission, such as solvent, pH, and metal ions, are investigated. Quenching of fluorescence by Cu2+ through chelation enhancement quenching effect with a high selectivity allowed the establishment of a Cu2+ sensor with an LoD of 0.57 ppm and a ratiometric estimation with an LoD of 0.73 ppm. Metal binding (2 : 1) stoichiometry and quenching constant (0.0072 mol?1s?1) are calculated from Job's and Stern-Volmer plots. Density functional theory (DFT) calculations are in accordance with the experimental results. Competitive replacement of TPI-9 by amino acids restores ESIPT, consequently, the fluorescence. Thus, an off-on fluorescence sensor for amino acid estimation is developed under 1 minute incubation. A linear relationship between amino acid concentration and fluorescence intensity is in 0-20 ?g/mL range, and the LoD is less than 2.2 ?g/mL. 2023 Wiley-VCH GmbH. -
A concise route to fused tetrazolo scaffolds through 10-camphor sulfonic acid auto-tandem homogeneous catalysis and mechanistic investigation
10-Camphor sulfonic acid (10-CSA) as an organo-catalyst has gained interest due to its versatile solubility and easiness of handling. This work reports a simple synthetic method through non-classical Biginelli for the construction of tetrazolo pyrimidine (4a-m) and quinazolines (4a?-o?). Azolopyrimidines and quinazolines are of great pharmaceutical importance. Numerous compounds are currently in use for the treatment of different diseases. Therefore their synthesis is industrially inevitable. Employing aldehydes, 1,3-dicarbonyls, and 5-Aminotetrazole, we report eco-friendly, cost-effective catalysis through a tandem reaction catalyzed by the 10-CSA that gave excellent yields, 7095 % for tetrazolo quinazoline and 4576 % tetrazolo pyrimidines respectively. The homonuclear NOESY analysis confirms the selective formation of one isomer. All the compounds are characterised by 1H NMR, 13C NMR, and MS. Investigation of the reaction mechanism by both experimental and theoretical studies provides evidence. Mechanism of the reaction was also explained utilizing the information from mass spectrometry monitoring. DFT calculation carried out at PBEPBE (Perdew-Burke-Ernzerhof) functional and 6-31G (d,p) basis set level of theory of the various intermediates observed supports the experimental evidence. 2023 Elsevier B.V. -
Azole-Based Antibacterial Agents: A Review on Multistep Synthesis Strategies and Biology
This article reviews current multistep synthesis strategies of azole-based antibacterial agents. In recent years, extensive use of chemical agents in treating different diseases resulted in the development of drug resistance. The war on multidrug resistance has resulted in the most significant loss to the worlds economy. Thus, the expansion of development of novel and potential candidates such as azoles and its derivatives is an escalating area in the field of medicinal chemistry. Azole compounds are increasingly being considered necessary in drug discovery paradigms as a number of them serve as lead compounds for the discovery of potent therapeutic agents. They have been used to treat bacterial, fungal, malarial, viral, and other general infections. They have also been known for their anticancer and anti-inflammatory activities. Their efficacy has been attributed to their electron-rich property, resulting in the formation of non-covalent bonds to the receptor proteins. Current research has given us a significant collection of synthetic strategies in the progress of azole compounds. This review article describes the survey of literature regarding multistep synthetic methods in the preparation of azole-based compounds and their antibacterial properties in the last 5 years. 2021 Taylor & Francis Group, LLC. -
An Experimental Investigation on Flexural Strength of Ferrocement Slab Made of Slag Sand Partially Replaced with Iron Ore Tailings
Effective use of slag sand and Iron Ore Tailings and other waste obtained from the manufacturing industry and mining industry like waste foundry sand, will reduce the negative impact on the environment and also will provide opportunities for effective use of natural resources and contribute to sustainability. The aim of this research project is to study the flexural strength of ferrocement slab made of slag sand partially replaced with iron ore tailings with sustainability point of view. Investigation of 48 slab panels of 700mm 300 mm size with thickness 25 mm and 30 mm was conducted using 1 and 2 layers of weld mesh reinforcement casted with different percentage of iron ore tailings. Slabs were tested in Universal Testing Machine, which showed good results with 15% of iron ore tailings. Published under licence by IOP Publishing Ltd. -
Effect of source-substrate distance on the transparent electrode properties of spray pyrolysed aluminium doped zinc oxide thin films
The wide band gap zinc oxide is a potential metal oxide that has been widely used in optoelectronic applications. The zinc oxide thin films demonstrate excellent conductivity and transparency enabling them for transparent electrode applications. The aluminium doping is an efficient route in further improving the conductivity without compromising the transparency and scalable spray pyrolysis is an effective approach in realizing high quality thin films. Our current study focuses on the effects of distance between the substrate and spray nozzle on the structural, morphological, optical, and electrical properties of aluminium doped zinc oxide. Our results suggests that this spray parameter has appreciable impact on the thin film properties and can be optimized for tuning properties. We explain this in detail backed by the characterization of thin films by X-ray diffraction, Atomic Force Microscopy, UVVis-NIR spectroscopy, Photoluminescence and Hall effect measurements. 2021 -
Determinants of Food Security in the Gulf Cooperation Council: A Cointegration Approach with an Autoregressive Distributed Lag Model
This paper examines the dynamics of the food import bill for the Gulf Cooperation Council (GCC) during the period 1980 2019 using a co-integration approach of the autoregressive distributed lag (ARDL) model. The study ascertains that the food market in the GCC is highly dependent on imports, which makes it vulnerable to any import disruption. The model confirms that there is a long-term relationship between the food import bill and its dynamics, with an adjustment rate of 37%, indicating that 37% of the deviations from the long-run path are corrected annually. The study demonstrates that in the long run, the food import bill was positively influenced by Gross domestic product (GDP) per capita, exports, inflation, global food prices, and regional instability and negatively influenced by the local production index. Population growth has a significant impact only in the short run. The implications of the findings were discussed, and a food security framework for the GCC has been developed. Engineered Science Publisher LLC 2023. -
Incorporating the metaverse into the green banking revolution: Spearheading the implementation of eco-friendly financial practices
This study aims to explore the awareness and perceptions of green banking among bankers and customers in rural and semi-urban areas of India. A structured questionnaire was employed to gather information from 807 customers and 200 officials of selected commercial banks, utilizing the snowball sampling method. The study utilized chi-square and factor analysis techniques. The chi-square test results revealed an association between educational status and the customer's opinion regarding green banks. Factor analysis derived three key factors influencing the adoption of green banking: convenience and environmental sustainability, financial and technological advantages, and customer retention and prestige. The findings indicate that green banking services provide more benefits to its customers than traditional banking. 2024, IGI Global. -
Performance Analysis of Deterministic Finite Automata and Turing Machine Using JFLAP Tool
In real life, the increased data accessing speed and data storage ability is required by most of the machinery fields. However, the real-world problems can be studied effectively with the combination of scientific computational techniques with the mathematical models. Automata theory is known to be the popular mathematical model. Towards most of the software and hardware related applications, the computational methods are analyzed and designed using significant automata theory concepts (likely, pushdown automata (PDA), Turing machines (TMs) and finite automata (FA)). Hence, the conventional lecture-driven style has attracted the reflective preferences of learners using these abstract natured concepts. But the lecture-driven teaching style has less motivated the computer engineering learners. In order to learn automata theory and computational models, we introduce the PDA and TM in a virtual platform. However, this work has motivated the improvement of longitudinal experimental validation and learning using the modern technology. Java Formal Languages and Automata Package (JFLAP) tool is used to write our simulators in JAVA language and the results are obtained from each machine through simulating the input strings. 2021 World Scientific Publishing Company. -
Synthesis and characterization of CeO2/Bi2O3/gC3N4 ternary Z-scheme nanocomposite
An effective and facile phytogenic method was used to prepare CeO2/Bi2O3 and CeO2/Bi2O3/gC3N4 composites using Eichhornia crassipes phytoextract. The synthesized catalysts were characterized using techniques such as XRD, FTIR, UV-DRS, PL, SEM-EDAX, XPS, zeta potential, and TGA. These catalysts showed diverse photocatalytic and optical properties due to the alteration in the bandgap. The synthesized composites exhibited good photocatalytic activity by degrading Malachite green (MG) dye. The increase in the photocatalytic activity could be attributed to the p-n heterojunction of the catalysts with efficient charge separation and strong oxidative ability. The modified photocatalysts showed excellent catalytic activity and reusability under visible light. The superior efficiency and its applications in environmental remediation make these catalysts a potential candidate for photocatalysis. 2020 The American Ceramic Society -
Eco friendly nitration of toluene using modified zirconia
Nitration of toluene has been studied in the liquid phase over a series of modified zirconia catalysts. Zirconia, zirconia- ceria (Zr0.98Ce0.02)O2, sulfated zirconia and sulfated zirconia- ceria were synthesised by co precipitation method and were characterised by X-ray diffraction, BET surface area, Infra red spectroscopy analysis (FTIR), Thermogravimetric analysis (TGA), Scanning Electron Microscopy (SEM), and Energy Dispersive X ray analysis (EDAX). The acidity of the prepared catalysts was determined by FTIR pyridine adsorption study. X-ray diffraction studies reveal that the catalysts prepared mainly consist of tetragonal phase with the crystallite size in the nano range and the tetragonal phase of zirconia is stabilized by the addition of ceria. The modified zirconia samples have higher surface area and exhibits uniform pore size distribution aggregated by zirconia nanoparticles. The onset of sulfate decomposition was observed around 723 K for sulfated samples. The catalytic performance was determined for the liquid phase nitration of toluene to ortho-, meta- and para- nitro toluene. The effect of reaction temperature, concentration of nitric acid, catalyst reusability and reaction time was also investigated. 2013 BCREC UNDIP.