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This research discusses the investigation of heat and mass transfer in a magnetohydrodynamic (MHD) Casson fluid (CF) flow over an exponentially porous stretching sheet. The analysis takes into account the existence of thermal radiation, viscous dissipation, chemical reactions, and the influence of velocity and thermal slips. A recognized Casson model is taken into account in order to distinguish the characteristics of Casson fluid from those of Newtonian fluids. Using the geometry under consideration, the current physical problem is modeled. Appropriate similarity conversions are implemented to reduce the resultant set of coupled nonlinear PDEs to a set of nonlinear ODEs. By implementing the Keller-Box technique, numerical solutions to these reduced non-dimensional governing flow field equations are obtained. Tables and diagrams are utilized to illustrate the physical behavior of various control parameters. The temperature profile is enhanced and velocity profile diminished as the CF parameter value increased, according to this study. An increase in the velocity slip factor resulted in a diminution in the velocity field, while a gain in the thermal and concentration contours. With growing amounts of the chemical reaction factor, the concentration profile exhibited a decline. Indeed, the similar outcomes elucidated in this paper exhibit a remarkable correspondence with solutions that have been previously documented in the academic literature. This research may be motivated by a desire to improve the comprehension of fluid flow in different engineering and environmental situations, where these conditions are common, such as geothermal energy extraction, thermal management, chemical processing industries, and environmental control technologies.

Hybrid nanofluid is crucial in improving the efficiency of heat transmission in thermal engineering applications, particularly the cooling of electrical equipment, heat exchangers, fuel cells, printing machines, etc. This study sought to investigate the augmentation of heat and mass transmission by the use of a rotating hybrid nanofluid consisting of a mixture of gold and silver nanoparticles suspended in water and ethylene glycol (50:50) past a heated Riga surface with velocity slip and suction. The energy equation is constructed using nonlinear radiation and heat consumption. The impact of both homogeneous and heterogeneous processes on the hybrid nanofluid is also explored. The governing mathematical model begins with partial differential equations that are converted into ordinary differential equations using a suitable conversion technique. The results of numerical computations are recorded as graphs and tables using the bvp4c scheme in MATLAB. It is noticed that both directional velocities undergo significant negative changes as a result of enhanced values of the rotational parameter. The higher levels of the radiation parameter resulted in significant enhancements in the thermal profile. The falling behavior of the nanoparticle concentration profile is recorded against a greater quantity of both chemical reaction parameters. Based on our analysis, when the Biot number changes from 0.4 to 0.8, the most significant heat transmission gradient occurs.

This paper investigates the effects of radiation, internal heat source and magnetohydrodynamics (MHD) on the mixed convective boundary layer flow of a Casson nanofluid within a porous medium that is saturated and subject to an exponentially stretching sheet. The nanofluid model incorporates Brownian motion and thermophoresis, and the Darcy model is employed for the porous medium. By applying an appropriate similarity transformation, the nonlinear governing boundary layer equations are converted into a set of nonlinear coupled ordinary differential equations. These equations are then solved numerically using the Hermite wavelet method, with simulations conducted through the MATHEMATICA programming language. The analysis covers various aspects including temperature distribution, velocity, solute concentration and several engineering parameters such as skin friction coefficients, the Nusselt number (rate of heat transfer) and the Sherwood number (rate of mass transfer), all evaluated based on dimensionless physical parameters. The results indicate that elevated radiation intensifies temperatures and leads to thicker thermal boundary layers. As the Casson parameter increases, both the velocity and the momentum boundary layer become narrower. Additionally, a more pronounced chemical reaction rate reduces the thickness of the solutal boundary layer. The accuracy and reliability of the numerical Hermite wavelet method are validated through a comparative analysis with previous studies, demonstrating excellent concordance and confirming the robustness of the computational approach.

This study undertakes a numerical investigation into the two-phase magnetohydrodynamic (MHD) flow of a novel Al₂O₃-Ag/ethylene glycol (30%)–water dusty Maxwell hybrid nanofluid within a porous stretched cylinder incorporates the influential factor of thermal radiation. Notably, it pioneers exploration into the flow characteristics of Maxwell nanofluids and hybrid nanofluids containing dust particles over a porous cylinder, an uncharted domain in the existing literature. By adeptly simplifying the governing partial differential equations into nonlinear ordinary differential equations (ODEs) using judiciously chosen similarity variables, our research employs MATLAB’s bvp4c scheme to obtain numerical solutions, presented both graphically and in tabular form. Our results unveil significant insights: the Maxwell fluid parameter and magnetic parameter exhibit a dual effect of enhancing heat transfer while mitigating velocity gradients. Moreover, increasing the curvature parameter exerts a favorable influence on the velocity and temperature profiles of both phases. Furthermore, the fluid-particle interaction parameter emerges as a pivotal factor shaping velocity and temperature profiles in the dust phase, while the radiation parameter notably amplifies heat transfer rates. Remarkably, our investigation reveals a notable 26% increase in total skin friction and a nearly 13.5% enhancement in heat transfer within the dusty Maxwell hybrid nanofluid configuration compared to the dusty Maxwell nanofluid arrangement. These findings hold profound practical implications for addressing real-life engineering challenges, offering invaluable insights into optimizing heat transfer and velocity profiles across diverse technical applications. They pave the way for the development of enhanced cooling mechanisms and highly efficient heat exchangers, crucial for tackling multifaceted engineering challenges.

We study the radiation of photons from a classical charged particle. We particularly consider a situation where the particle has a constant velocity in the distant past, then is accelerated, and then has a constant velocity in the distant future. Starting with no photons in the distant past we seek to characterize the quantum state of the photon field in the distant future. Working in the Coulomb gauge and in a $C^{\ast }$-algebra formulation, we give sharp conditions on whether this state is or is not in Fock space.

Microcapsules comprising alginate and hyaluronic acid that can be decomposed by radiation are under development. Previously, we observed that radiation efficiently decomposes microcapsules comprising alginate and hyaluronic acid in the ratio 2:1 by weight. In this study, Yttrium (Y) was added to these microcapsules to improve their decomposition by radiation.

Hyaluronic acid solutions (0.1% weight/volume) were mixed into 0.2% alginate solution, and carboplatin (0.2 mmol) was added; the resultant was used for capsule preparation. Capsules were prepared by spraying the material into mixtures of 4.34% CaCl₂ solution supplemented with Y at final concentrations from 0 to 1.0 × 10⁻²%.

These capsules were irradiated by a single dose of 0.5, 1.0, 1.5, or 2 Gy with ⁶⁰Co γ-rays. Immediately after irradiation, we observed the release of the core contents of the microcapsule using a micro Particle Induced X-ray Emission (PIXE) camera.

The mean diameter of the microcapsules was 37.3 ± 7.8 μm. Maximum content of radiation-induced release was observed for liquid-core microcapsules prepared by polymerization in a 4.34% CaCl₂ solution supplemented with 5.5 × 10⁻³% Y.

Microcapsules that release antigen-capturing nanoparticles (AC-NPs) with macrophage inflammatory protein-3 alpha (MIP-3$\alpha$) and anti-programmed death-1 (PD-1) antibody are developed, and these microcapsules have the ability to enhance immunoresponses through cross-priming of cluster of differentiation 8+ (CD8+) T cells by dendritic cells (DCs) in vivo in BALB/c mice.

Lipid protamine hyaluronic acid nanoparticles containing AC-NPs generated via nanoprecipitation of 4 mg/mL of polylactic-co-glycolic acid (PLGA), 1,000 ng/mL of MIP-3$\alpha$ and 400 $\mu$g of anti-PD-1 were mixed with 1 mL of 4.0% alginate and 3.0% of hyaluronate and then sprayed with 0.5 mM of ferrous chloride. These capsules were injected subcutaneously around LM17 tumor in the left hind legs of BALB/c mice. The tumors were exposed to a radiation dose of 10 or 20 Gy from 100 keV soft X-ray radiation. PLGA AC-NPs and MIP-3$\alpha$ were released in response to the radiation dose.

PLGA AC-NPs captured tumor-derived protein antigens are released by exposure to radiation, and these antigens were transported to DCs that were recruited and activated by MIP-3$\alpha$, intensifying the DC-associated cross-priming of CD8+ T cells. These treatments resulted in increased antitumor effect and reduced metastasis by abscopal effect. Our targeted immunotherapy may lead to better tumor therapy.

This study aimed to investigate the effect of the particles releasing chitosan upon exposure to radiation on inhibition of metastasis.

A 10 mL solution of water containing 0.2% weight/volume alginate, 0.1% hyaluronic acid, and 100-mg chitosan was sprayed into the vibrating solution through a stainless mesh filter (pore size: 0.8 $\mu$m) using an ultrasound disintegrator, thereby generating chitosan particles. Further, $1\times 10^{10}$ particles floating in 0.1 mL normal saline were subcutaneously injected around the 4TI cells-derived tumor in the left hind legs of six-week-old male C3He/N mice. Six hours after injection, tumors were exposed to 10 Gy or 20 Gy of 100-keV soft X-ray radiation. The release of chitosan was expressed as the frequency of ruptured chitosan particles 12 h after radiation. The antimetastatic effect was confirmed by a reduction in the number of metastatic pulmonary nodules 21 days after completion of treatment.

More than $56.3\pm 4.3$% of the chitosan particles released chitosan in response to radiation. The particles releasing chitosan had a prolonged antimetastatic effect when compared with the particles not releasing chitosan, thereby resulting in a significantly greater antimetastatic effect lasting for four weeks since the completion of treatment, in tumors treated with both 10 Gy and 20 Gy of radiation.

Hence, particlizing chitosan could be useful in reducing metastasis in irradiated tumors.

Under the auspices of Defense Advanced Research Project Agency's Microsystems Technology Office (DARPA/MTO) Low Power Electronics Program, the Mayo Foundation Special Purpose Processor Development Group is exploring ways to reduce circuit power consumption, while maintaining or increasing functionality, for existing military systems. Applications presently being studied include all-digital radar receivers, electronic warfare receivers, and other types of digital signal processors. One of the integrated circuit technologies currently under investigation to support such military systems is the IBM Corporation silicon germanium (SiGe) BiCMOS process. In this paper, design methodology, simulations and test results from demonstration circuits developed for these applications and implemented in the IBM SiGe BiCMOS 5HP (50 GHz f_T HBTs with 0.5 μm CMOS) and 7HP (120 GHz f_T HBTs with 0.18 μm CMOS) technologies will be presented.

The types of applications affected by radiation effects in III-V devices have significantly changed over the last four decades. For most applications III-V ICs have provided sufficient radiation hardness. Some expectations for hardened soft error applications did not materialize until much later. Years of research defined that not only material properties, but device structures, layout practices and circuit design influenced how III-V devices were susceptible to certain radiation effects. The highest performance III-V ICs due to their low power-speed energy products will provide challenges in ionizing radiation environments from sea level to space.

Single-event effects are a serious concern for high-speed III-V semiconductor devices operating in radiation-intense environments. GaAs integrated circuits (ICs) based on field effect transistor technology exhibit single-event upset sensitivity to protons and very low linear energy transfer (LET) particles. The current understanding of single-event effects in III-V circuits and devices, and approaches for mitigating their impact, are discussed.

This review concerns radiation effects in silicon Charge-Coupled Devices (CCDs) and CMOS active pixel sensors (APSs), both of which are used as imagers in the visible region. Permanent effects, due to total ionizing dose and displacement damage, are discussed in detail, with a particular emphasis on the space environment. In addition, transient effects are briefly summarized. Implications for ground testing, effects mitigation and device hardening are also considered. The review is illustrated with results from recent ground testing.

The context of SOI technology is briefly presented in terms of wafer fabrication, configuration/performance of SOI devices, and operation mechanisms in partially and fully depleted MOSFETs. Typical radiation effects, induced by single particles and cumulated dose, are evoked: BOX degradation, parasitic bipolar action, coupling effects, transistor latch, and back-channel conduction. The future of SOI is tentatively explored, by discussing the further scalability of SOI-MOSFETs as well as the innovating architectures proposed for the ultimate generations of SOI transistors.

Scaling of complementary metal oxide semiconductor (CMOS) technologies to the sub-100 nm dimension regime increase the sensitivity to pervasive terrestrial radiation. Diminishing levels of charge associated with information in electronic circuits, interactions of multiple transistors due to tight packing densities, and high circuit clock speeds make single event effects (SEE) a reliability consideration for advanced electronics. The trend to adapt and apply commercial IC processes for space and defense applications has provided a catalyst to the development of infrastructure for analysis and mitigation that can be leveraged for advanced commercial electronic devices. In particular, modeling and simulation, leveraging the dramatic reduction in computing cost and increase in computing power, can be used to analyze the response of electronics to radiation, to develop and evaluate mitigation approaches, and to calculate the frequency of problematic events for target applications and environments.

In this study, hybrid nanofluid free convection has been simulated within a permeable domain involving Lorentz effect. To solve and simulate the problem, Control Volume-based Finite Element Method (CVFEM) method is applied. In addition, the non-Darcy model has been used to apply permeable condition in equations. The influence of hybrid nanoparticles (Fe₃O₄$+$MWCNT) inside water as base fluid has been studied. Meanwhile, source term of radiation impact has been described for different nanoparticle shapes. The impacts of substantial variables such as Darcy number, radiation factor, magnetic strength and Rayleigh number on nanofluid behavior were fully revealed. It can be concluded that enhancing permeability factor can improve the Nusselt number but reverse behavior can be reported for Lorentz forces.

CVFEM usage for modeling of nanomaterial flow style in a permeable elliptical tank including Lorentz effect was scrutinized in the current research. Hybrid material with use of homogeneous model was applied and radiation term has been involved in governing equations. Outputs have been depicted in contours and plots. In addition, a new formula for Nu was reported. Augment of Nu by considering greater permeability can be explained by stronger temperature gradient in cases with higher Da. Nanomaterial flow becomes suppressed with augment of Ha which results in lower Nu. As Ha was augmented from 0 to 20, 18% reduction was reported in Nu. Permeability has favorable influence on nanomaterial flow and the impact of Ha is the opposite of permeability.

Current investigation deals with influence of inclusion of nanoparticles within the permeable medium within a tank with circular outer wall. The inner surface is hot and the radiative term has been imposed in temperature equation. Vorticity formula helps us to remove the pressure terms from equations and CVFEM was incorporated to calculate the amount of scalars in each node. With correlating the current data from previous paper, verification procedure was done which demonstrates good accuracy. Permeability has crucial role and greater values of Da results in stronger thermal penetration and isotherms become more disturbed. Intensity of cell augments with rise of Da about 70% in absence of Ha. Impose of Rd cannot affect the isotherms too much while it can change the Nu regarding the definition of this factor. When $\text{Da}=0.01$, growth of Ha can decline the strength of eddy about 35%. Given $\text{Ha}=20$, as Da increases, Nu enhances about 10.24% and 0.25% when $\text{Ra}=1$e5 and 1e3, respectively. Replacing platelet with sphere shape can augment the Nu about 0.38% and 0.6% when $\text{Ha}=20$ and 0, respectively.

In this work, a mathematical model of fractional-order in fluid will be analyzed numerically to describe and study the influence of thermal radiation on the magnetohydrodynamic flow of nanofluid thin film which moves due to the unsteady stretching surface with viscous dissipation. The set of nonlinear fractional differential equations in the form of velocity, temperature and concentration which describe our proposed problem are tackled through the spectral collocation method based on Chebyshev polynomials of the third-kind. This method reduces the presented model to a system of algebraic equations. The effect of the influence parameters which governs the process of flow and mass heat transfer is discussed. The numerical values of the dimensionless velocity, temperature and concentration are depicted graphically. Also, computations of the values of skin-friction, Nusselt number and Sherwood number have been carried out and presented in the same figures. Finally, our numerical analysis shows that both the magnetic and the unsteadiness parameters can enhance the free surface temperature and nanoparticle volume fraction.

To detect the influence of MHD on migration of hybrid nanopowders, CVFEM has been employed in this paper. Mixture of Fe₃O₄ and MWCNT was added in water and for calculating properties, experimental formulas were utilized. To increase the convective mode, porous media has been used and tank was experienced in the horizontal magnetic field. In governing equations, there exist two new terms, one for permeable media and the other for MHD effect. Such complex physics needs special numerical approach and CVFEM has been utilized for this goal. Final formulation of PDEs did not have pressure terms and the stream function scalar was introduced. As permeability of zone enhances, nanopowders can transfer faster and the interaction of them with wall enhances, so, Nusselt number augments as well as stream function. Besides, employing higher Ha, the force against the buoyancy force increases and the velocity of operating fluid declines which provides lower convective flow. With rise of Ha, stream function declines about 48% and Nu declines about 31.92% when $\mathrm{\text{Da}}=100$. As Da rises, Nu rises about 33.43% when $\mathrm{\text{Ha}}=0$. Augment of Rd leads to augmentation of Nu.

In this investigation, numerical modeling for the behavior of nanomaterial inside a porous zone with imposing Lorentz force has been illustrated. The working fluid is a mixture of H₂O and CuO and due to concentration of 0.04, it is reasonable to use the homogeneous model. Two-temperature model for porous zone was employed in which new scalar for calculating temperature of solid region was defined. CVFEM has been applied to model this complex physics. Radiation terms were considered and their influence on Nu has also been considered. Verification with benchmark proves greater accuracy. Dispersing nanopowders helps the fluid to increase velocity and reduce the temperature of inner wall. Rise of Ra results in three strong eddies inside the zone which creates two thermal plumes and it reduces the temperature of square surface about 68%. With rise of Nhs, the power of counter-clockwise vortex reduces about 61.6% and inner wall becomes warmer about 33.3%. Raising the Ha makes thermal plume to vanish and cooling rate decreases about 46.6%. Augment of Nhs makes Nu to reduce about 5.08% while augment of Ra makes it to augment about 35.64%. Also, augmenting Ha makes Nu to decline about 56.45%.