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Investigation of fluorescence enhancement and antibacterial properties of nitrogen-doped carbonized polymer nanomaterials (N-CPNs)
Carbonized Polymer Nanomaterials (CPNs) have acquired substantial research interest in recent years due to their budding applications in various optical and electrochemical studies like electrocatalysis, solar cells, biosensing, etc. Due to their stability and toxicity, the enhancement of CPNs' properties was the primary cause of concern. Herein, we synthesized Nitrogen-doped (N-doped) N-CPNs using the one-step hydrothermal approach of PVA and PVDF polymers with Nitric acid (HNO3) as the nitrogen source. The luminescence intensity was observed to be enhanced by increasing nitrogen doping concentration. The synthesized fluorescent samples exhibited significant antibacterial properties, making them useful in biomarkers, sensing strategies, drug delivery, etc. Doped PVA samples exhibited negligible antibacterial activity, but nitrogen-doped PVDF samples displayed considerable biocidal activity against gram-positive bacteria, according to antibacterial research. Each sample's growth inhibition was distinct and species-specific. 2022 Taylor & Francis Group, LLC. -
Investigation of GaSb (p+) Pocket doped GaSb/Si Vertical TFETs for High-Frequency Analog Circuits
Abstract: This paper reports on the design, modelling, and performance analysis of a GaSb/Si Heterojunction Vertical Tunnel Field-Effect Transistors (HVTFETs), employing band-to-band tunneling (BTBT). The device structure includes a p+-GaSb source and an intrinsic Si-channel/drain, forming a heterojunction that enhances tunneling efficiency due to the staggered band alignment. The obtained ON and OFF currents are 1 105 and 1 1018 A/?m. The saturation drain current (IDSat) rises with gate voltage, measured as: 2.7 108 A for VG = 0.5 V, 3.4 108 A for VG = 0.6 V and 3.9 108 A for VG = 0.7 V. The off-state current (IOFF) is very low (~1019 A) for all the VG values, indicating effective suppression of leakage current. The derived gm values for gate voltages of 0.5, 0.6, and 0.7 V are 5.4 105, 5.5 105, and 5.6 105 S, respectively, indicating effective gate control and transconductive efficiency for signal amplification. The combination of these characteristics would enable high fT and fmax, making the device suitable for broadband and millimeter-wave applications in the radio frequency (RF). The suggested GaSb/Si heterojunction vertical TFET has commendable analog/RF attributes, featuring a peak cutoff frequency (fT) of 8.91 GHz and a maximum oscillation frequency (fmax) of 5.8 GHz. The device demonstrates an intrinsic gain (Av) of 11.2 and a gain-bandwidth product (GBW) of 99.79 GHz, indicating substantial promise for RF front-end applications, including low-noise amplifiers, mixers, and voltage-controlled oscillators, as well as energy harvesting applications. Pleiades Publishing, Ltd. 2026. -
Investigation of hot corrosion behavior of plasma sprayed cermet composite coatings on titanium and special steel alloys
In the present study, titanium-15 alloy and a special steel alloy (MDN 420) were used as base materials. These components are employed in high-temperature applications. Three types of pure powders were deposited on titanium-15 and a special steel (MDN 420) alloys. The three coatings were 35 % (WC-Co) + 65 % (Cr3C2-NiCr), 70 % NiCrAlY + 30 % TiO2, and 70 % NiCrAlY+25%Cr2O3 + 5%YSZ. The coatings and base alloys underwent various metallurgical, mechanical, and hot corrosion tests. The hot corrosion behavior of the coatings was investigated in a Na2SO460%V2O5 molten salt medium at 700 C, with an accuracy of 5 C. Each test cycle consisting of 50 cycles, with heating followed by 1 h cooling for 20 min. When three coatings were compared, NiCrAlY+Cr2O3 + YSZ coating exhibited superior resistance to hot corrosion on both the alloys. The enhanced corrosion resistance of the NiCrAlY+Cr2O3 + YSZ coating was attributed to the formation of a protective oxide layer containing Cr2O3.The tests were conducted in a highly acidic molten salt environment, with Na2SO4 being less soluble (60 % V2O5). The results showed that the NiCrAlY+Cr2O3 + YSZ coating displayed better corrosion resistance for titanium-15 and MDN 420 alloys, when compared to the other two coatings. The formation of an oxide layer containing Cr2O3 was the main reason for the improved corrosion resistance. 2025 Elsevier B.V. -
Investigation of launch power and regenerator placement effect on the design of mixed-line-rate (MLR) optical WDM networks
In recent years, owing to the consistent increase in volume and heterogeneity of the traffic, telecommunication networks have undergone significant innovations. Existing studies have shown that, by adopting a mixed-line-rate (MLR) strategy, wavelength division multiplexed (WDM) optical networks can cost-effectively respond to the diverse variety of traffic requirements which have heterogeneous service demands. However, due to the existence of physical layer impairments [specifically cross-phase modulation (XPM)], adjacent channels on different line rates may exhibit serious degradation of signal quality and optical reach. In such cases, launch power governs the bit-error rate as it affects both the signal and the noise power due to XPM. Therefore, an intelligent choice of launch power on different line rates can significantly reduce the network cost. Further, in MLR optical networks, trade-off between regenerator placement and the launch power attains importance and needs to be addressed. In this work, we investigate the launch power and regenerator placement effect on the design of a MLR WDM optical network. The obtained simulation results show that the network cost is (i) mainly controlled by power values of the 10/100/400 Gbps channels, and (ii) decreases for a cost model in which, compared to 10G transponders, high-bit-rate transponders have higher cost decay. Further, with a lower cost model, it is found that more numbers of regenerators can be deployed, simultaneously minimizing the network cost. 2017, Springer Science+Business Media New York. -
Investigation of memory influences on bio-heat responses of skin tissue due to various thermal conditions
Advancement of new technologies such as laser, focused ultrasound, microwave and radio frequency for thermal therapy of skin tissue has increased numerous challenging situations in medical treatment. In this article, a new meticulous bio-heat transfer model based on memory-dependent derivative with dual-phase-lag has been developed under different thermal conditions such as thermal shock and harmonic-type heating. Laplace transform method is acquired to perceive the analytical consequences. Quantitative results are evaluated for displacement, strain and temperature along with stress distributions in time domain by adopting the technique of inverse Laplace transform. Impacts of the constituents of memory-dependent derivativeskernel functions along with time-delay parameter are analysed on the studied fields (temperature, displacement, strain and stress) for both thermal conditions separately using computational results. It has been found that the insertion of the memory effect proves itself a unified model, and therefore, this model can better predict temperature field data for thermal treatment processes. 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Investigation of nanocrystalline structure in selected carbonaceous materials
The structural parameters of nine Indian coals were determined by X-ray diffraction (XRD) and Raman spectroscopy. The study revealed that the coals contain crystalline carbon of turbostratic structure with amorphous carbon. The stacking height (Lc) and interlayer spacing (d002) of the crystallite structure of the coals ranged from 1.986 to 2.373 nm and from 0.334 to 0.340 nm, respectively. The degree of graphitization was calculated to range from 42% to 99%, thereby confirming the ordering of the carbon layers with the increase in coal rank. An exponential correlation was observed among the aromaticity (fa), the lateral size (Lc), and the rank (I20/I26), suggesting that the coal crystallites are nanocrystalline in nature. A very strong correlation was observed between the structural parameters (fa, d002, Lc, the H/C ratio, and I20/I26), the volatile matter content, and the elemental carbon content, indicating the structures of coals are controlled by the degree of contact metamorphism. The Raman spectra exhibited two prominent bands: the graphitic band (G) and the first-order characteristic defect band (D). The deconvolution resulted in five peaks: G, D1, D2, D3, and D4. The intense D1 band, which appeared at ~1350 cm-1, corresponds to a lattice vibration mode with A1g symmetry. The D2 mode, which appeared at ~1610 cm-1, arises from the structural disorder as a shoulder on the G band. University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2014. -
Investigation of nanocrystalline structure in selected carbonaceous materials /
International Journal of Minerals, Metallurgy and Materials, Vol.21, Issue 9, pp.322-328, ISSN No: 1674-4799. -
Investigation of photoluminescence emission from ?-Ga2O3: Ce thin films deposited by spray pyrolysis technique
Ce doped Ga2O3 thin films for different doping concentrations (3 at%, 4 at%, 5 at%, 6 at%, 7 at%, and 8 at%) were deposited by spray pyrolysis method. X-ray diffraction analysis confirmed the crystalline structure as that of monoclinic ?-Ga2O3. The effect of doping on the band gap of the material was studied by UV-Visible spectroscopic method and the thickness of the film and refractive index were measured by ellipsometric technique. The photoluminescence excitation and emission spectra were recorded for pure and doped samples and the energy band scheme with possible radiative and nonradiative transitions were elucidated. Concentration quenching effect was observed, and the underlying mechanism responsible for quenching effect was studied based on Dexter theory. 2021 Elsevier B.V. -
Investigation of PWM Methods for a 9 Level Boost Inverter Using CD-type Carriers
The article introduces an innovative boost inverter topology that utilizes two switching capacitors and a single Direct Current (DC) source to generate a nine-level output voltage waveform. This design eliminates the need for sensors or additional electronics since the capacitor voltages automatically balance themselves. Unlike traditional inverters, an input DC boost converter isnt necessary, as the output voltage is often twice the input voltage, particularly when the inverter is powered by a natural source. Furthermore, novel modulation techniques proposed for CD-type carrier waves exhibit enhanced efficiency, higher RMS voltage, and reduced harmonic distortion (THD). The effectiveness of the suggested carriers has been verified through investigations employing phase disposition (PD), alternate phase opposition disposition (APOD), and phase opposition disposition (POD). Each technique described under 9LBI has been assessed using a MATLAB/Simulink configuration. The operational and dynamic performance of the proposed architecture has been modeled using MATLAB/Simulink. 2024, TUBITAK. All rights reserved. -
Investigation of Spectroscopic Parameters and Trap Parameters of Eu3+-Activated Y2SiO5 Phosphors for Display and Dosimetry Applications
Using the solid-state reaction technique, varied Y2SiO5 phosphors activated by europium (Eu3+) ions at varied concentrations were made at calcination temperatures of 1000 C and 1250 C during sintering in an air environment. The XRD technique identified the monoclinic structure, and the FTIR technique was used to analyze the generated phosphors. Photoluminescence emission and excitation patterns were measured using varying concentrations of Eu3+ ions. The optimal strength was observed at a 2.0 mol% concentration. Emission peaks were detected at 582 nm and 589 nm for the 5D0?7F1 transition and at 601 nm, 613 nm, and 632 nm for the 5D0?7F2 transition under 263 nm excitation. Because Eu3+ is naturally bright, these emission peaks show how ions change from one excited state to another. This makes them useful for making phosphors that emit red light for use in optoelectronics and flexible displays. Based on the computed (1931 CIE) chromaticity coordinates for the photoluminescence emission spectra, it was determined that the produced phosphor may be used in light-emitting diodes. The TL glow curve was examined for various doping ion concentrations and durations of UV exposure levels, revealing a broad peak at 183 C. Using computerized glow curve deconvolution (CGCD), we calculated the kinetic parameters. 2024 by the authors. -
Investigation of Spectroscopic Parameters and Trap Parameters of Eu3+-Activated Y2SiO5 Phosphors for Display and Dosimetry Applications
Using the solid-state reaction technique, varied Y2SiO5 phosphors activated by europium (Eu3+) ions at varied concentrations were made at calcination temperatures of 1000 C and 1250 C during sintering in an air environment. The XRD technique identified the monoclinic structure, and the FTIR technique was used to analyze the generated phosphors. Photoluminescence emission and excitation patterns were measured using varying concentrations of Eu3+ ions. The optimal strength was observed at a 2.0 mol% concentration. Emission peaks were detected at 582 nm and 589 nm for the 5D0?7F1 transition and at 601 nm, 613 nm, and 632 nm for the 5D0?7F2 transition under 263 nm excitation. Because Eu3+ is naturally bright, these emission peaks show how ions change from one excited state to another. This makes them useful for making phosphors that emit red light for use in optoelectronics and flexible displays. Based on the computed (1931 CIE) chromaticity coordinates for the photoluminescence emission spectra, it was determined that the produced phosphor may be used in light-emitting diodes. The TL glow curve was examined for various doping ion concentrations and durations of UV exposure levels, revealing a broad peak at 183 C. Using computerized glow curve deconvolution (CGCD), we calculated the kinetic parameters. 2024 by the authors. -
Investigation of speech synthesis, speech processing techniques and challenges for enhancements
The sound produced by any human being or instrument can be used for various applications using the concept of extraction or selection. Using this concept, virtual sounds are produced which is prime requirement for various speech synthesis applications. In this paper we review the different speech processing methodologies, parameters involved and the various applications based on the speech quality produced. Though an overview is given on the processing and involved parameter, priority is given to the speech enhancement application. This survey helps to identify the challenges involved in various processing technique involved in speech enhancement of healthy and disordered speech. These findings with different speech production and speech synthesis techniques will help to improve the quality in various application of speech to text (STT), text to speech (TTS), Automatic speech production (ASP) and Automatic speech recognition (ASR). Copyright 2019 American Scientific Publishers All rights reserved. -
Investigation of structural formation of starting composition 2245 in the Bi-Pb-Sr-Ca-Cu-O system superconductors /
Journal of Solid State Physics, Vol.2014, pp.127-133, ISSN No: 2356-7643 (Print), 2314-6842 (Online). -
Investigation of surface and interface effects of piezoelectric quasicrystal different models with propagation of shear horizontal and anti-plane shear horizontal wave; [??????????????????????????????????]
Based on the theoretical representation of piezoelectric quasicrystal, a generalized dynamic model is built to represent the transmission of wave aspects in surface acoustic pulse nano-devices. Surface elasticity, surface piezoelectricity, and surface permittivity help to include the surface effect, which equals additional thin sheets. It is shown that, under certain assumptions, this generalized dynamic model may be simplified to a few classical examples that are appropriate for both macro and nano-scale applications. In the current work, surface piezoelectricity is used to develop a theoretical model for shear horizontal (SH) waves where it contains the surface piezoelectricity theory and a linear spring model to quantitatively and qualitatively explore SH waves in an orthotropic piezoelectric quasicrystal layer overlying an elastic framework (Model I), a piezoelectric quasi-crystal nano substrate, and an orthotropic piezoelectric quasicrystal half-space (Model II). The theoretical model stimulates the numerical results, which establish the critical thickness. As the piezoelectric layers thickness gets closer to nanometres, surface energy must be included when analyzing dispersion properties. Furthermore, the effects of surface elasticity and density on wave velocity are investigated individually. The authors establish a parameter, precisely the ratio of the physical modulus along the width direction to along the direction of wave travel. The surface effects impact on the general characteristics of piezoelectric structures is seen as a spring force acting on bulk boundaries. Analytical presentation of frequency equations for both symmetric and anti-symmetric waves pertains to the case of an electrical short circuit in Model II. The project aims to analyze SH waves in orthogonal anisotropic, transversely isotropic piezoelectric layered nanostructures, providing a practical mathematical tool for surface effects analysis and adaptability to other wave types, including Rayleigh waves and acoustic surface waves. The Chinese Society of Theoretical and Applied Mechanics and Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Investigation of the Axe-shaped Radio Galaxy J1051+5523 with uGMRT
We present a multifrequency study of the bent-tail radio galaxy J1051+5523, located in the galaxy cluster WHL J105147.4+552309. This wide-angle tail (WAT) galaxy exhibits a complex radio morphology, characterized by a right-angled bend in the northern jet, which resembles an axe, and multiple kinks in the southern jet, as observed in the deep uGMRT radio observations. The radio power of J1051+5523 at 150 MHz is estimated to be, placing it in the transition zone between FRI and FRII radio galaxies. The spectral index map reveals a flat core and relatively flat lobes, which may indicate ongoing particle acceleration or a relatively young population of relativistic electrons in the lobes. Further, we estimate the equipartition magnetic fields, and spectral ages of the northern and southern lobes to be approximately 150 and 153 Myr, respectively, suggesting a long-lived radio source with sustained active galactic nucleus (AGN) activity. A relative velocity of 278 2643 is obtained for the host galaxy. Due to the large uncertainty associated with the relative velocity estimates, the contribution of ram pressure to the jet bending remains inconclusive. The low mass of the host cluster () and the lack of diffuse X-ray emission indicate a reduced likelihood of major mergers, but minor mergers or interactions remain possible. We propose that the observed WAT morphology of J1051+5523 is likely shaped by a combination of ram pressure and/or buoyant forces within the cluster environment. 2025 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. -
Investigation of the correlation between optical and ?-ray flux variations in the blazar Ton 599
The correlation between optical and ?-ray flux variations in blazars reveals a complex behaviour. In this study, we present our analysis of the connection between changes in optical and ?-ray emissions in the blazar Ton 599 over a span of approximately 15 yr, from 2008 August to 2023 March. Ton 599 reached its highest flux state across the entire electromagnetic spectrum during the second week of 2023 January. To investigate the connection between changes in optical and ?-ray flux, we have designated five specific time periods, labelled as epochs A, B, C, D, and E. During periods B, C, D, and E, the source exhibited optical flares, while it was in its quiescent state during period A. The ?-ray counterparts to these optical flares are present during periods B, C, and E; however, during period D, the ?-ray counterpart is either weak or absent. We conducted a broad-band spectral energy distribution (SED) fitting by employing a one-zone leptonic emission model for these epochs. The SED analysis unveiled that the optical-ultraviolet emission primarily emanated from the accretion disc in quiescent period A, whereas synchrotron radiation from the jet dominated during periods B, C, D, and E. Diverse correlated patterns in the variations of optical and ?-ray emissions, like correlated optical and ?-ray flares, could be accounted for by changes in factors such as the magnetic field, bulk Lorentz factor, and electron density. On the other hand, an orphan optical flare could result from increased magnetic field and bulk Lorentz factor. 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. -
Investigation of the fractal footprint in selected EURIBOR panel banks
EURIBOR emerged as a conventional proxy for a risk-free rate for a reasonably long period of time after the creation of the Eurozone. However, the joy was short-lived, as the global credit crisis shook the markets in mid-2008. Significant counterparty risk embedded in a derivative transaction cannot be left out. EURIBOR reflects the credit spread on borrowing. Hence, risk and uncertainty are inextricably linked here. This study investigates five banks out of 19 panel banks that manage EURIBOR in various Eurozone countries. These banks, HSBC, ING, Deutsche Bank, the National Bank of Greece and Barclays, are tested from January 2009 to December 2017 on a daily basis. Bank specific EURIBOR can be predicted in all five cases with different degrees. The trace of a profound herd is observed in the case of the National Bank of Greece, others were relatively mild in nature. The customer base and their risk grade were recognized as the main factor. Their information asymmetry and derived information entropy suggest embedded chaos and uncertainty. Bikramaditya Ghosh, Corlise Le Roux, Anjali Verma, 2020. -
Investigation of the therapeutic potential of daphnetin, derived from Daucus carota leaves, against colorectal cancer: insights from in-silico, DFT, in-vitro, and fluorescence studies on its interactions with proteins
Daphnetin (NAP) has a sophisticated structure containing two oxygen-linked rings, which have long attracted medicinal chemists in the drug discovery process. Daphnetin features a coumarin structure with two hydroxy groups positioned side by side at the 7th and 8th carbons, making it an essential component for developing a novel triple point co-prodrug. We have isolated NAP from the leaves of Daucus carota (commonly known as carrot). NAP showed a good docking score with the EGFR protein obtained from network pharmacology, while molecular dynamics simulations evaluated the stability. ROS generation assays, MTT assays, etc. confirmed that NAP exhibits significant cytotoxic effects on HCT-116 cells. An investigation of the reverse phase interaction of NAP with BSA and ovalbumin, where proteins are added to the ligand solution, demonstrated fluorescence enhancement, ensuing in a observable colour transformation from neutral to blue, through binding-constants of 4.8 104 M?1 and 2.08 104 M?1. 2025 Informa UK Limited, trading as Taylor & Francis Group. -
Investigation of thermal performance of moving concave parabolic porous fin wetted by water based MoS2 nanofluid using Homotopy Perturbation Method
Recent advancements in nanotechnology have led to significant improvements in the design, manufacturing, and thermal efficiency of engineering systems. Nanofluids, when combined with extended surfaces, enhance heat transfer performance, helping to prevent overheating while also offering improved stability, durability, and adaptability across various environmental conditions. This research focuses on the thermal response of a moving porous fin featuring a concave parabolic profile, immersed in a nanofluid composed of water as the base fluid and molybdenum disulfide (MoS2) nanoparticles. The governing nonlinear nanofluid model is nondimensionalized, and thermal characteristics such as temperature profiles, heat transfer rates, efficiency, and fin effectiveness are obtained using the Homotopy Perturbation Method (HPM). The effects of important dimensionless parameters on thermal profiles are examined through graphical illustrations. The results demonstrate that temperature rises with increases in the Peclet number and thermal conductivity, whereas it decreases as porosity, radiation, convection, and emissivity parameters increase. Furthermore, the inclusion of MoS2 nanofluid leads to an average heat transfer enhancement of approximately 3.84% compared to conventional fluids under radiative conditions. 2025 -
Investigation on AI-Based Techniques in Applications for Detecting Fatal Traffic Accidents
The difficulties with road accident rates today rank among the top concerns for health and social policy in nations across the continents. In this essay, we've spoken about the fatalities and injuries brought on by traffic accidents in several Indian states. We have also shed light on the various factors that contribute to traffic accidents. Many researchers have reported various methods for identifying automobile crashes or accidents that are discussed in this work. Additionally, we covered collision avoidance systems and their various kinds. An examination of the analysis techniques used to comprehend the numerous causes causing accidents is also included in the study. Traditional models are frequently used to identify problems such driver weariness, drowsiness, driving while intoxicated, and distractions. 2023 IEEE.