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The three-dimensional bioconvective flow of Sisko nanofluid under Robin's conditions
The proposed model investigates three-dimensional bioconvective Sisko nanofluid flow under Robin's conditions. The Sisko nanofluid has versatile implications in drilling fluids, cement slurries, waterborne coatings, and so on. Furthermore, the inclusion of gyrotactic microorganisms prevents the deposition and agglomeration of the nanoparticles in the base fluid. Buongiorno's model is included to explore the behavior of Brownian motion and thermophoretic factors. The energy and mass transmissions along with the gyrotactic microorganism density are illustrated by the partial differential expression system with Robin's conditions. These are further reframed into an ordinary differential equation system with the aid of similarity transformation. The developing model is tackled by using the MAPLE inbuilt package BVP. The nanofluid acts as a goodcooling agent for higher values of the thermophoresis parameter. Furthermore, the pseudoplastic nanofluid performs better than the dilatant nanofluid. The developed model is very useful in energy production and engineering products. 2021 Wiley Periodicals LLC -
Three dimensional mixed convection flow of hybrid casson nanofluid past a non-linear stretching surface: A modified Buongiorno's model aspects
The purpose of this study is to determine the role of mixed convection, Brownian motion, and thermophoresis in the dynamics of Casson hybrid nanofluid in a bidirectional nonlinear stretching sheet. For the flow model, a combination of Tiwari and Das models, as well as Buongiornos model, is considered. The thermophysical characteristics of Gr, TiO2, and blood are employed. With the assistance of relevant similarity transformation, the describing flow equations of a Casson hybrid nanofluid model are reformed in the form of a system with a single independent variable. The solution for these equations is obtained using the RKF-45 approach. The velocity, temperature, and concentration fields are visually developed for both linear and non-linear stretching sheets, and the implications of the major parameters are presented in detail. It is clear from the current investigation that heat and mass transfer characteristics of fluid are better in the case of linear stretching than non-linear stretching. Furthermore, the mixed convection parameter is found to enhance the fluid flow velocity. However, the trend is quite opposite in the thermal and concentration fields. Meanwhile, the increase in the yield stress caused due to the rise in the Casson parameter decreases the flow velocity. 2021 Elsevier Ltd -
Bioconvection of a radiating hybrid nanofluid past a thin needle in the presence of heterogeneous-homogeneous chemical reaction
The photocatalytic nature of TiO2 finds applications in medicinal field to kill cancer cells, bacteria, and viruses under mild ultraviolet illumination and the antibacterial characteristic of Ag makes the composition Ag - TiO2 applicable for various purposes. It can also be used in other engineering appliances and industries such as humidity sensor, coolants, and in footwear industry. Hence, this study deals with the analysis of the effects of magnetic field, thermal radiation, and quartic autocatalysis of heterogeneous-homogeneous reaction in an electrically conducting Ag - TiO2 - H2O hybrid nanofluid. Furthermore, the gyrotactic microorganisms are used as active mixers to prevent agglomeration and sedimentation of TiO2 that occurs due to its hydrophobic nature. The mathematical model takes the form of partial differential equations with viscosity and thermal conductivity being the functions of volume fraction. These equations are converted to ordinary differential equations by using similarity transformation and are solved by RKF-45 method with the aid of shooting method. It is observed that the increase in the size of the needle enhances the overall performance of the hybrid nanofluid. Furthermore, the temperature of the hybrid nanofluid increases with the increase in volume fraction. It is observed that the friction produced by the Lorentz force increases the temperature of the nanofluid. It is further observed that the heterogeneous reaction parameter has more significant effect on the concentration of bulk fluid than the homogeneous reaction parameter. Copyright 2021 by ASME. -
Numerical simulation of JeffreyHamel flow of nanofluid in the presence of gyrotactic microorganisms
The nonlinear differential equations play a prominent role in mathematically describing many phenomena that occur in our world. A similar set of equations appear in this paper that govern the nanofluid flow between two non-parallel walls in the presence of gyrotactic microorganisms that are responsible for bioconvection. These microorganisms ensure the safety of the appliance by avoiding the accumulation of nanoparticles and the movement of these nanoparticles within the fluid experiences major slip mechanisms as discussed by Buongiorno. Further, the orientation of the channel is described by the parameter ? and based on this parameter, the channel is said to be converging if (Formula presented.) and the channel is diverging if (Formula presented.). The case when (Formula presented.) corresponds to a channel with parallel walls, hence this case is ignored. Following these assumptions, the set of governing equations thus formed are made dimensionless and further solved by the Differential Transformation Method (DTM) and the outcomes are discussed through graphs. The analysis is performed for both converging and diverging orientations of the channel. The results indicate that the temperature and the concentration profiles increase with the increase in Brownian motion parameters in both divergent and convergent channels. Meanwhile, the increase in Reynolds number decreases the temperature of the nanofluid. Through the simulation, it was observed that the heat flow is taking place along the isothermal planes in the case of the diverging channel but it was uniform in the domain of the converging channel. 2021 Informa UK Limited, trading as Taylor & Francis Group. -
FAMILY OF CONGRUENCES FOR (2, ?)?REGULAR BIPARTITION TRIPLES
Though congruences have their limitations, they have significant importance in the field of number theory and helps in proving many interesting results. Thus, this article has adopted the technique and properties of congruences to identify and prove a set of congruent properties for integer partition. The partition of a positive integer is a way of expressing the number as a sum of positive integers. One such partitions known as regular bipartition triple are discussed in this article. New congruences modulo even integers and modulo prime (p ? 5) powers are derived for (2, ?)?regular bipartition triples. Also infinite families of congruences modulo 2 for some (2, ?)?regular bipartition triples are derived. The theorems stated in this article are proved using the q?series notation and some of the prominent results such as Eulers pentagonal number theorem and Jacobis triple product identities. There are certain lemmas which are derived using these results that help in proving the major results of this article. 2022, RAMANUJAN SOCIETY OF MATHEMATICS AND MATHEMATICAL SCIENCES. All rights reserved. -
A FAMILY OF CONGRUENCES FOR (2, ?)?REGULAR BIPARTITIONS
The congruence of certain restricted partition functions known as regular bipartition is discussed in this paper. We particularly investigate the (2, ?)-regular bipartitions of n, denoted by B2,? (n), and establish certain congruences for B2,? (n) when ? ? 3. We derive infinite families of congruences modulo 4 for the (2, 3)-regular bipartition. We also obtain a generalisation of the regular bipartition for modulo p and p2. Indian Mathematical Society, 2022. -
Impact of bioconvection on the free stream flow of a pseudoplastic nanofluid past a rotating cone
In the current work, the repercussions of Brownian motion and thermophoresis on the three-dimensional free stream flow of tangent hyperbolic (pseudoplastic) nanofluid past a rotating cone are explored. The tangent hyperbolic model expresses the characteristics of a shear-thinning nanofluid. Furthermore, oxytactic microorganisms were used as mixers to actively stabilize the nanoparticles. The movement of these microorganisms within the nanofluid gives rise to a major phenomenon termed bioconvection. The flow of nanofluid past a rotating cone finds applications in the field of nuclear reactors, biomedical applications, solar power collectors, steam generators, and so on. The mathematical model is designed using Buongiorno's model that describes the two major slip mechanisms experienced by the nanoparticles moving within a fluid namely thermophoretic force and Brownian motion. The model thus formed is nondimensionalized using the apt similarity transformation. The resulting system is solved by the (Formula presented.) technique by adapting the shooting method. The velocity, temperature, concentration, and motile density profiles are graphically interpreted for different flow parameters involved in the study. It was observed that thermophoresis reduces concentration and enhances the temperature whereas Brownian motion enhanced both temperature and concentration profiles. Also, the increase in the mixed convection parameter effectively decreased the temperature of the nanofluid. 2022 Wiley Periodicals LLC. -
Flow of nanofluid past a stretching cylinder subject to Thompson and Troian slip in the presence of gyrotactic microorganisms
Incorporating the Thompson and Troian slip condition, this work studies the bioconvective flow of a nanofluid past a vertically stretching cylinder. The Thompson and Troian slip deals with the molecular scale interactions at the solidfluid interface, which plays a pivotal role in the fluid flow analysis. This study helps in understanding the behaviours of fluid flow in the presence of non-linear slip past a vertically stretching cylinder. The corresponding partial differential equations (PDEs) for momentum, energy, concentration of nanoparticles, and concentration of microbes are developed using Buongiornos model. A suitable similarity transformation is then applied to these PDEs, converting them into a set of ordinary differential equations (ODEs). The RungeKuttaFehlberg (RKF-45) method is utilized to calculate the numerical solution of the resulting ODE problem. The results demonstrate that the interaction of slip conditions, viscous dissipation, heat source, and bioconvection causes complex flow patterns and heat transfer characteristics. These observations are extremely relevant for applications including better oil recovery procedures, biomedical engineering, and microfluidic devices where exact control over nanofluid behaviour is necessary. Some of the major observations of the study include the enhancement of the temperature in the nanofluid for higher Eckert numbers, control of fluid flow through an external magnetic field, and Peclet number significantly decreased the motile density in the nanofluid. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024. -
Flow of nanofluid past a stretching cylinder subject to Thompson and Troian slip in the presence of gyrotactic microorganisms
Incorporating the Thompson and Troian slip condition, this work studies the bioconvective flow of a nanofluid past a vertically stretching cylinder. The Thompson and Troian slip deals with the molecular scale interactions at the solidfluid interface, which plays a pivotal role in the fluid flow analysis. This study helps in understanding the behaviours of fluid flow in the presence of non-linear slip past a vertically stretching cylinder. The corresponding partial differential equations (PDEs) for momentum, energy, concentration of nanoparticles, and concentration of microbes are developed using Buongiornos model. A suitable similarity transformation is then applied to these PDEs, converting them into a set of ordinary differential equations (ODEs). The RungeKuttaFehlberg (RKF-45) method is utilized to calculate the numerical solution of the resulting ODE problem. The results demonstrate that the interaction of slip conditions, viscous dissipation, heat source, and bioconvection causes complex flow patterns and heat transfer characteristics. These observations are extremely relevant for applications including better oil recovery procedures, biomedical engineering, and microfluidic devices where exact control over nanofluid behaviour is necessary. Some of the major observations of the study include the enhancement of the temperature in the nanofluid for higher Eckert numbers, control of fluid flow through an external magnetic field, and Peclet number significantly decreased the motile density in the nanofluid. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024. -
Crop Disease and Pest Management in Agriculture via UAV Remote Sensing and Advanced Machine Learning Models
Pests and diseases greatly reduce crop quality and yield; therefore, IA relies on effective pest and disease control. UAVs have become a crucial remote sensing (RS) tool for agricultural process monitoring and management. This study will examine major advances in this field using bibliometric methodologies including author co-occurrence and keyword co-contribution studies. The suggested technique involves preprocessing, feature extraction, and model training. Data quality improves with preprocessing. UAV images are used for feature extraction, focusing on canopy structure and height. PPO is trained the prediction model. Compared to ultramodern GANs and LSTM networks, the recommended model wins. The model consistently outperforms competitors with 91.17 percent accuracy. The study suggests employing UAVs in smart farming to reduce pests and diseases. The suggested model's accuracy and reliability improve crop quality and production by solving agricultural monitoring and management problems. 2025 IEEE. -
Enhancing Crude Oil Price Prediction with Neural Network Models
A nations economic, social, and national security are all severely affected by variations in crude oil prices, which is a basic energy source. Research on accurately forecasting price changes for crude oil is always progressing. This research presents a forecasting strategy for crude oil pricing using artificial neural networks. The presented model uses standardization techniques to prepare the historical data for the subsequent processes. It is possible to predict future prices by using a Feed Forward Neural Network (FFNN) with four layers. West Texas Intermediate (WTI) and Brent crude oil prices are utilized on a daily, weekly, and monthly basis to demonstration and confirmation. Directional statistic, accuracy of prediction, the model is evaluated using root mean square error and mean absolute error expressed as percentages. Empirical findings confirm that the suggested approach performs better than any of the previous approaches. Additionally, it is noted that the presented method achieved higher prediction in contrast to other methods. The Author(s), under exclusive license to Springer Nature Switzerland AG 2026. -
A Machine Learning Approach to Crude Oil Price Prediction Using Support Vector Machine (SVM)
Crude oil is one of the most important energy sources, and fluctuations in its international prices affect all aspects of the economy. The price of crude oil is influenced by several variables, and the length of time that each component has an effect differs giving an increase in non-linear oil price features. Although it is a complex task, identifying the most essential factor influencing for precise predicting, crude oil prices are essential. Therefore, this study aims to employ a machine learning model to address the intricate relationships among different factors. Primarily, it gathers data regarding West Texas Intermediate (WTI) and Brent crude oil prices as well as macroeconomic variables. Secondly, the data is normalized to prepare it for further analysis. Finally, a crude oil prediction model is constructed using Support Vector Machine (SVM) to predict future international crude oil prices. The daily, weekly, and monthly prices are used to confirm the models efficacy developed using WTI and Brent oil. The models performance is also evaluated by incorporating various combinations of macroeconomic variables to find the most influential factor. Results from experiments show indicates the benchmark model was much exceeded by the developed model and performed very well in terms of prediction accuracy. The findings reveal that selecting the appropriate variables can greatly enhance prediction accuracy. This model has the potential to provide valuable insights for traders, investors, and energy-related enterprises, offering beneficial guidance for decision-making purposes. The Author(s), under exclusive license to Springer Nature Switzerland AG 2026. -
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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 -
Thermal diffusivity study of one-pot synthesised polypyrrole silver nanocomposite by thermal lens method
We are reporting the results of our exploration of the thermal lens method to determine the thermal diffusivity of Ppy and Ppy/Ag nanocomposites synthesised by simple, cost effective in situ chemical oxidative polymerisation. EDAX spectrum confirms the presence of silver in the samples. Raman analysis shows that the increase in the concentration of silver in composite results in an increase in the conjugation length of the samples. We have adopted the dual-beam pump-probe technique to determine the thermal diffusivity of polypyrrole and polypyrrole silver nanocomposite with varying silver concentrations. We report suppression of thermal diffusivity of polypyrrole with the addition of a small concentration of silver and an enhanced thermal diffusivity with an increase in the concentration of silver with ethanol as the base fluid. Increased thermal diffusivity of the samples makes them suitable for use as coolants. 2022 Elsevier Ltd -
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. -
Polymeric Nanocomposites and Their Applications
A polymer is a macromolecule comprising numerous repeating subunits linked by covalent bonds. The word polymer arises from Greek, with polus denoting many and meros denoting parts. Although humans have used polymers long before, their chemical properties were studied only in the nineteenth century. The Author(s), under exclusive license to Springer Nature Switzerland AG 2025. -
Synthesis of polypyrrole silver graphene ternary nanocomposite and its thermal diffusivity study by thermal lens method
Efficient thermal management materials with tunable thermal diffusivity are increasingly required for advanced electronic, photonic, and energy applications. However, simultaneously achieving both thermal conductivity enhancement and thermal insulation within a single material system remains a significant challenge. In this work, we have synthesized polypyrrole silver graphene (PPy/Ag/Gr) ternary nanocomposites with varying concentrations of graphene by a simple one-pot chemical synthesis method.The photoluminescence spectrum of all the samples of PPy/Ag/Gr showed a quenching in the intensity due to the presence of graphene. Raman spectrum analysis confirmed good coordination of silver and graphene in the ternary composite. Morphological study was done using field emission scanning electron microscopy (FESEM). The thermal diffusivity of the binary composites polypyrrole silver (PPy/Ag) and polypyrrole graphene (PPy/Gr) as well as the ternary composites with varying concentrations of graphene were done using the highly sensitive thermal lens method using two laser sources, one as a pump source and the other as a probe beam. The results of the study show that the thermal diffusivity (D) of PPy/Ag/Gr with 0.2 wt.% of graphene is slightly greater than the binary composites and can be used as a coolant. Another exciting result of this study is that at higher concentrations of graphene the D values of the ternary composites decrease below the D value of the base fluid used. This interesting property of the samples can be exploited by using them as thermal insulators 2025 The Authors -
Polypyrrole/silver/graphene ternary composites for high-performance Ku-band electromagnetic interference shielding
Unwanted electromagnetic waves can significantly affect the performance of electronic devices and communication systems. A high-performance electromagnetic interference shielding (EMI) material is a solution to this issue. This study introduces a cost-effective one-pot synthesis method for polypyrrole/silver (Ppy/Ag), polypyrrole/graphene (Ppy/Gr) and polypyrrole/silver/graphene (Ppy/Ag/Gr) ternary composites with adjustable graphene concentrations. Detailed structural and morphological analyses using FTIR, XRD and STEM confirm the successful incorporation of Ag nanoparticles and graphene into the polypyrrole matrix. The total shielding effectiveness (SET) of the ternary composites in the Ku band shows an impressive 30.86 dB at 12.7 GHz for the 5 wt.% graphene composite, primarily driven by absorption mechanisms (SEA> SER). The synergistic interaction between Ag, which provides conductive pathways, and graphene, which offers structural reinforcement, significantly enhances interfacial polarisation and conductivity, surpassing the performance of binary counterparts (Ppy/Ag and Ppy/Gr. The results of this work introduce a lightweight, potent and economical composite material for EMI shielding applications in the Ku band. 2025 Elsevier B.V. -
Leveraging digital yarn dyeing for colour consistency in apparel weaving
When compared to traditional processes, digital yarn dyeing provides substantial benefits in terms of color control, versatility, and environmental impact. However, technological obstacles and constraints exist. The promise of digital dyeing may be realized by carefully selecting technology, optimizing ink consumption, and adopting stringent quality control methods, resulting in improved colour constancy and a more sustainable textile sector.