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Radiative heat transfer of nanomaterial on a convectively heated circular tube with activation energy and nanoparticle aggregation kinematic effects
The improvement of the thermal conductivity of the nanoliquid due to the inclusion of a certain amount of nanoparticles is well known. However, the cause of the observed abnormal improvement remains unclear. For this reason, the aggregation kinematics of nanoparticles is significant for evaluating the appropriate thermal effect of particles at the nanoscale. The scope of nanomaterials can be seen in various engineering and industrial fields such as nuclear reactor coolants, heat exchangers, aircraft coolants, microreactor coolants, automobile radiators, solar collectors, etc. Therefore, this study investigates the effects of the aggregation of nanoparticles on radiative nanoliquid flow with activation energy over a horizontal tube subjected to the convective thermal boundary conditions. Experimentally verified correlations of multiwall carbon nanotube aggregation are utilized. The response surface methodology (RSM) is used to determine the optimum levels of the physical parameters to maximize the mass transfer rate of the nanoliquid. The magnitude of the volume fraction and velocity are superior in the absence of aggregation kinematics than in the presence of nanoparticles aggregation mechanism. From the RSM analysis, the maximum Sherwood number obtained is 1.1384 with desirability d = 0.9993. The present results may have applications in nanoliquid-dependent structures, heating/cooling processes, and thermal systems. 2021 Elsevier Ltd -
Radiative heat transfers of Carreau fluid flow over a stretching sheet with fluid particle suspension and temperature jump
The current study is to deliberate the flow and heat transfer of a Carreau fluid over a stretching sheet with fluid particle suspension. The temperature jump is also taken into account. The standard nonlinear system is resolved numerically via Runge-Kutta based shooting scheme. Role of substantial parameters on flow fields as well as on the fiction factor and heat transportation rates are determined and conferred in depth through graphs. It's found that the velocity profile decreases and temperature profile increases, with an increasing the values of Weissenberg parameter. Further, the higher thermal slip parameter reduces the thermal boundary layer thickness. The thermal boundary layer thickness of fluid and dust particles decreases with the rise in Prandtl number. 2017 The Authors -
Radiative heat transport and unsteady flow in an irregular channel with aggregation kinematics of nanofluid
In this study, an unsteady free convective heat transfer and the laminar flowof incompressible nanoliquid in a wavy channel subjected to the nanoparticles aggregation effects were studied. For the investigation, ethylene glycol-based nanofluid with titania nanoparticles was used. Here, the role of the nanoparticle aggregation, thermal radiation, applied magnetic field, and internal heat absorption is examined. A semi-analytical solution of the complicated partial differential equation is obtained by the method of regular perturbation. The effect of several parameters on velocity and temperature profile has been studied. In addition, Nusselt number (Nu) and skin friction (Formula presented.) are also examined and analyzed with the help of graphs. It has been observed that the velocity profile enhances with aggregation effect than without aggregation effect. The aggregation effects are minimal for smaller volume fraction of nanoparticles. A reverse trend near the wavy wall is visible for all parameters. The magnitude of velocity decreased as an effect of the applied magnetic field, whilethe magnitude of velocity increased due to radiative heat flux. Furthermore, the heat sink mechanism reduces the magnitude of the nanofluid temperature. 2021 Wiley Periodicals LLC -
Radiative nonlinear 3D flow of ferrofluid with Joule heating, convective condition and Coriolis force
Characteristics of heat transport mechanism in three-dimensional ferrofluid flow past a deformed surface subjected to the Coriolis and Lorentz forces are analyzed. The impacts of Joule heating, nonlinear thermal radiation, viscous dissipation and convective condition are also accounted. The carrier fluid (water) is embedded by Fe3O4 nanoparticles. The boundary layer approximations are employed in problem statement. Stretching transformations are utilized to form nonlinear ODE system from governed PDE system. The subsequent system is treated numerically via Runge-Kutta-Fehlberg method. Effects of relevant parameters on different flow fields are discussed comprehensively with help of graphs. It is established that the heat transfer rate is enhanced due to Coriolis and Lorentz forces. Furthermore, Fe3O4 nanoparticles enhance the Nusselt number significantly in comparison with Al2O3 nanoparticles. 2017 -
Radio pulsar sub-populations (II): The mysterious RRATs
Several conjectures have been put forward to explain rotating radio transients (RRATs), the newest subclass of neutron stars, and their connections to other radio pulsars. This work discusses these conjectures in the context of the characteristic properties of the RRAT population. Contrary to expectations, it is seen that: (a) the RRAT population is statistically un-correlated with the nulling pulsars and (b) the RRAT phenomenon is unlikely to be related to old age or death-line proximity. It is perhaps more likely that the special emission property of RRATs is a signature of them being later evolutionary phases of other types of neutron stars which may have resulted in restructuring their magnetic fields. 2022, Indian Academy of Sciences. -
RADON in GROUNDWATER of MAGADI TALUK, RAMANAGARA DISTRICT in KARNATAKA
Radon is a water-soluble radioactive noble gas produced from the alpha decay of 226Ra in uranium series. Its presence in drinking water and open air increases the risk of lung and intestinal cancers in human beings. In view of this, radon concentration in groundwater and its dose due to inhalation and ingestion to the population of Magadi taluk of Ramanagara district in Karnataka state, India was studied. The groundwater samples were analyzed for radon concentration using emanometry technique. The study showed that the radon concentration in this area varied from 27.4 1.0 to 167.5 3.9 Bq/L and the effective dose ranged from 104.2 2.7 to 636.2 11.0 ?Sv/a. The study also revealed that 95% of the 37 samples studied showed higher radon concentration compared to the UNSCEAR recommendation (40 Bq/L) and all the samples showed higher than the USEPA recommendation (11.1 Bq/L). Ten samples have concentration above the maximum permissible level prescribed by WHO (100 Bq/L). The groundwater samples are found to be slightly alkaline within the permissible limit of Indian Standards. 2018 The Author(s). Published by Oxford University Press. All rights reserved. -
Radon transform based image steganography in frequency domain /
International journal Of Applied Engineering Research, Vol.10, Issue 70, pp.830-834, ISSN No: 0973-4562. -
Radon transform processed neural network for lung X-ray image based diagnosis
A novel method for image diagnosis with artificial learning is presented-ray images tuberculosis patients is subjected to neural network learning for prediction of diagnosis. The X-ray images of lungs are normally difficult for diagnosis, since its similarity to lung cancer. Under and over diagnosis of lung X-ray images is a difficult medical problem to resolve. In the present work radon transform of the x-ray images is fed to back propagation neural network trained with Levenberg algorithm. The present methodology gives sharp results, distincting the normal and abnormal images. 2014 IEEE. -
Railway Track Crack Detection: A Comparative Study On Yolov7 And U-Net In Automated Inspection
For railway networks to remain operationally safe and avoid catastrophic failures, structural integrity is essential. Track cracks can be found using labor-intensive, slow, and human error-prone manual inspection techniques. In this work, two cutting-edge deep learning models - YOLOv8 andU-Net v2 - for automated railway track crack detection using high-resolution imagery from Unmanned Aerial Vehicles (UAVs) are compared. In a real-world inspection scenario, we compare the different strategies of precise semantic segmentation (U-Net) and real-time object detection (YOLOv8) in order to assess their relative trade-offs. We compare performance on important metrics such as precision, recall, intersection over union (IoU), and inference speed using a custom dataset that was taken by a DJI Matrice 300 RTK drone. This work is novel because it examines how each model's output - bounding boxes versus pixel-level masks - directly affects the usefulness for maintenance workflows from an application-focused perspective. According to our research, U-Net v2 offers the fine-grained information required for precise damage assessment, while YOLOv8 is best suited for quick, extensive screening. This study offers railway operators useful information for creating a multi-stage, hybrid inspection strategy that strikes a balance between accuracy and speed. 2025 IEEE. -
Rain of Life, Rain of Music: Music as Life Power in Indian Thought and Contemporary Musical Traditions
Conceived as a life force, rain has a significant place in Indian thought. Sanskrit and vernacular literary and religious texts, as well as visual arts, emphasise its auspiciousness and importance in human life. Additionally, through the use of poetical images and metaphors, these texts and images associate rain with music and identify thunder with drums. Through the analysis of compositions from the repertoire of different drums such as the dhrupad pakh?vaj, the mi??vu of K?tiy???a? Sanskrit theatre, and the ritual music of Brahmanical temples of Kerala, this article studies the association of drumming with rain as a symbol of life force, consciousness and enlightenment. 2022 South Asian Studies Association of Australia. -
RAINBOW CHROMATIC TOPOLOGICAL INDICES OF CENTRAL GRAPHS OF SOME GRAPHS
The chromatic topological indices concept was introduced recently. Many other variations concerning the chromatic topological indices have been studied lately. In this paper, we have calculated the first and second rainbow chromatic Zagreb indices and rainbow chromatic irregularity indices for central graph of some standard graph classes. Palestine Polytechnic University-PPU 2024. -
Rainbow degree-jump coloring of graphs
In this paper, we introduce a new notion called the rainbow degree-jump coloring of a graph. For a vertex v ? V(G), let the degree-jump closed neighbourhood of this vertex be defined as Ndeg [v] = {u: d(v, u) ? d(v)}. A proper coloring of a graph G is said to be a rainbow degree-jump coloring of G if for all v in V(G), c(Ndeg [v]) contains at least one of each color class. We determine a necessary and sufficient condition for a graph G to permit a rainbow degree-jump coloring. We also determine the rainbow degree-jump chromatic number, denoted by ?rdj (G), for certain classes of cycle related graphs. Mphako-Banda E.G., Kok J., Naduvath S., 2021. -
Rainbow Dominator Coloring of Graphs
Coloring and domination in graphs are two well explored areas of research in graph theory. Blending these notions, the dominator coloring of graphs was introduced in the literature; following which several variants of domination related coloring patterns have been defined and studied, based on different types of coloring and domination in graphs. A vertex coloring of a graph that demands the existence of a path in which every internal vertex between two vertices has a unique color is called a rainbow vertex coloring of the graph. In this article, we investigate the rainbow dominator coloring of graphs; a vertex coloring that combines the concepts of rainbow vertex coloring and dominator coloring of graphs. We discuss some properties of the rainbow dominator coloring of graphs and determine the rainbow dominator chromatic number of certain classes of graphs and their complements. 2025, SINUS Association. All rights reserved. -
Rainbow Dominator Coloring of Some Cycle Related Graphs
The concept of dominator coloring of graphs emerged as a combination of the two prominent structural aspects of graphs, namely coloring and domination in graphs. The vertex coloring that demands the existence of a rainbow path between any two vertices of a graph; that is, a path in which every internal vertex has a unique color, is called a rainbow vertex coloring of a graph. Melding the concepts of rainbow vertex coloring and dominator coloring of graphs, the rainbow dominator coloring of graphs has been studied, in the literature. In this article, we investigate the rainbow dominator coloring of some cycle related graphs, and their complements. 2025, SINUS Association. All rights reserved. -
Rainbow neighbourhood number of graphs
In this paper, we introduce the notion of the rainbow neighbourhood and a related graph parameter namely the rainbow neighbourhood number and report on preliminary results thereof. The closed neighbourhood N [v] of a vertex v ? V (G) which contains at least one coloured vertex of each colour in the chromatic colouring of a graph is called a rainbow neighbourhood. The number of rainbow neighbourhoods in a graph G is called the rainbow neighbourhood number of G, denoted by r?(G). We also introduce the concepts of an expanded line graph of a graph G and a v-clique of v ? V (G). With the help of these new concepts, we also establish a necessary and sufficient condition for the existence of a rainbow neighbourhood in the line graph of a graph G. 2019 Johan Kokand Sudev Naduvath and Muhammad Kamran Jamil. -
Raman Spectroscopy Applied to Polymer Composites and Nanocomposites
Raman Spectroscopy Applied to Polymer Composites and Nanocomposites summarizes, in a comprehensive manner, recent research accomplishments in this important area. The book offers an in-depth study of the current state-of-the-art, covering the fundamentals and recent experimental developments. Almost all the characterization techniques coupled in situ with Raman spectroscopy are discussed in detail. The book also covers various aspects of polymer applications, as well as related topics in polymer composites and nanocomposites. Filled polymers, reinforced plastics, thermoplastics, thermosets, elastomers, and rubbers are also discussed. The book is designed to address all aspects of Raman spectroscopy with respect to polymers and measurements, along with experimental conditions. It contains numerous case study examples to illustrate how Raman spectroscopy coupled in situ with more classical techniques can be useful to enhance material performance. 2026 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies. -
Raman spectroscopy investigation of camphor Soot: Spectral analysis and structural information
Raman spectra of camphor soot has been investigated and optimised with a Raman microscope system operated at laser excitation wavelength of 514.5 nm. Several band combinations for spectral analysis have been tested, and a combination of three Lorentian bands ( G,D1,D2) at about 1580, 1350 and 1620 cm-1, respectively, with Gaussian-shaped band (D3) at 1500 cm-1and 1200 cm-1 (D4) was best suited for the first order spectra. The second-order spectra were best fitted with Lorentian shaped bands at about 2450, 2700, 2900 and 3250 cm-1. The results are discussed and compared with X-ray diifraction measurements and SEM analysis. The camphor soot shows ? and P{cyrillic} bands which reveals the presence of crystalline graphitic carbon. The SEM micrographs of camphor show the presence of carbon nanostructures. 2013 by ESG. -
Raman spectroscopy: an introduction, instrumentation, and its applications in polymer composites and nanocomposites
Raman spectroscopy, a nondestructive technique based on molecular vibrations, offers insights into molecular structures and interactions through the inelastic scattering of monochromatic light. This method facilitates the identification of chemicals by using unique molecular fingerprints. The ability of this technique to analyze samples in situ, in any form, is very advantageous. Over the years, improvements have been made in the sensitivity and resolution of Raman spectroscopy in instrumentation and data analysis, which has broadened its range of applications in chemistry, biology, and materials research. Raman spectroscopy has become a vital tool for applied research and basic sciences. In the area of composites and nanocomposites, it offers tremendous possibilities, such as material identification, phase separation, and defect analysis, reinforcement agent characterization, stress and strain analysis, crystallinity and orientation, and micromechanical deformation. 2026 Elsevier Ltd. All rights reserved. -
Raman spectrum of graphite layers in Indian coal
Two Indian coals of different rank (bituminous and subbituminous coal) have been demineralized by chemical method. Fourier transform Raman spectroscopy studies have been performed to study the changes in functional groups. Well resolved G peak is observed at 1605 cm-1 and 1590 cm-1 both in bituminous coal and subbituminous coal. With HF leaching, this doublet is reduced to a singlet along with reduction of frequency to 1585 cm -1 in subbituminous coal, where as in bituminous coal the absorption become very distinct. Bituminous coal is showing more intense absorption with HF leaching in this region where as subbituminous coal is shown a reduction in intensity. G' band is observed at ? 2700 cm-1 with almost the same intensity as that of G band. This confirms the presence of multilayer formation of graphite layer. The defect band at 1355 cm-1 is due to benzene or condensed benzene rings present in amorphous carbon. This band is weak in the present study. This is mainly due to immature nature of subbituminous coal than the higher rank bituminous coal. Graphite structure is remained behind after chemical leaching liberated oxygenated functional groups and mineral groups. The decrease of ID/IG ratio indicates that graphitization is increased in bituminous coal. 2011 American Institute of Physics. -
Ramifications of Climate Change Induced by Anthropogenic Factors on Global Fish Population Scenario
One of the important consequences of climate change is its effect on the global fish population. Though not very highly pronounced each year, the effect of climate change is of cumulative nature. Global aquaculture is being affected by temperature changes of both water and air. Fluctuations in the ocean surface temperatures, ocean current patterns, wind speeds, and wave directions, all have its impact on aquaculture. Each year we see more and more incidences of extreme weather conditions in different parts of the world, be it in the form of hurricanes, heavy floods, etc. Fishes are subjected to various stress factors which in turn take a toll on its growth and development. This can lead to lower weight gain and increased mortality due to higher susceptibility to diseases. This, coupled with direct unsustainable anthropogenic activities in the oceans and rivers may lead to collapse of the marine and freshwater ecosystem. Recent studies have identified specific regions where marine aquaculture production will be positively and negatively affected. One of the sustainable ways of developing aquaculture in the coming decades would be by developing region-wise strategies to maintain or increase fish population levels and thus meet the global seafood demands even in 2050. The current review is an attempt to assess the effects of ocean warming, ocean acidification, and ocean deoxygenation on the growth, survival, and diversity of marine lifeforms and suggest ways to stop a complete collapse of marine fish population by 2050, the year for which the complete collapse is predicted based on projections. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.