Diffusion under the Effect of Lorentz Force


Book Description

It is generally believed that collisions of particles reduce the self-diffusion coefficient. In this book, Erik Kalz shows that in classical systems under the effect of Lorentz force, which are characterized by diffusion tensors with antisymmetric elements, collisions surprisingly can enhance self-diffusion. In these systems, due to an inherent curving effect, the motion of particles is facilitated, instead of hindered by collisions. Consistent with this the author finds that the collective diffusion remains unaffected. Using a geometric model, he theoretically predicts a magnetic field governed crossover from a reduced to an enhanced self-diffusion. The physical interpretation is quantitatively supported by the force autocorrelation function, which turns negative with increasing the magnetic field. Using Brownian-dynamics simulations, he validates the predictions.




Diffusion Under the Effect of Lorentz Force


Book Description

It is generally believed that collisions of particles reduce the self-diffusion coefficient. In this book, Erik Kalz shows that in classical systems under the effect of Lorentz force, which are characterized by diffusion tensors with antisymmetric elements, collisions surprisingly can enhance self-diffusion. In these systems, due to an inherent curving effect, the motion of particles is facilitated, instead of hindered by collisions. Consistent with this the author finds that the collective diffusion remains unaffected. Using a geometric model, he theoretically predicts a magnetic field governed crossover from a reduced to an enhanced self-diffusion. The physical interpretation is quantitatively supported by the force autocorrelation function, which turns negative with increasing the magnetic field. Using Brownian-dynamics simulations, he validates the predictions. About the Author Erik Kalz holds a master's degree in physics from the Technical University of Dresden. He is interested in statistical physics with applications in soft condensed matter physics and biological physics. In 2022 he will start his PhD in theoretical physics at the University of Potsdam.




Diffusion in Materials


Book Description

This volume is the proceedings of the NATO Advanced Study Institute, "Diffusion in Materials", held at "Centre Paul Langevin", Aussois, during March 12-25, 1989. There were 105 participants of whom 24 were lecturers and members of the international advisory committee. In addition to the participants from NATO countries, a small number of participants came from Australia, Hungary, Poland and Tunisia. The principal aim of the organizing committee was to bring together scientists of wide interest and expertise in the field of diffusion and to familiarize the young workers in material science with the wide range of theoretical models and methods and of experimental techniques . The Institute was concerned with the study of diffusion and related phenomena in solids which are at the cutting edge of novel technologies. The discussion of basic theories of defects in solids and their transport, with their applications in the understanding of diffusion processes in "simple solids" was followed by the wide range of current theoretical models and methods, experimental techniques and their potential. The lectures on the diffusion in specific materials included : metals, dilute and concentrated alloys, simple and compound semiconductors, stoichiometric and non-stoichiometric oxides, high-Tc compounds, carbides, nitrides, silicates, conducting polymers and thin films, ionic, superionic, amorphous and irradiated materials.




Collective Diffusion on Surfaces: Correlation Effects and Adatom Interactions


Book Description

As materials research focuses into finding ways to control the growth of atomic scale structures, there is correspondingly increasing emphasis on to the problem of surface diffusion. Clearly surface diffusion is the key process, which determines how atoms move on the surface. Controlling this motion can lead to the easy fabrication of well-controlled nanostructures broadening the present possibilities in nanotechnology. The paradigm of surface diffusion has outgrown its standard textbook description as a random walk on a rigid substrate. In real systems for more complex situations are encountered: interacting atoms are commonly present on the surface with their motions highly correlated, different phases form on the surface with different dynamics, large concentration gradients drive the system far away from the linear response regime, rich metastable structures form as a result of balanced interplay between different kinetic processes, substrate relaxation can change the energy landscape and the diffusion barriers, etc. The motivation behind this ARW was to bring together the international community working on these problems. We felt that the large number of researchers, new results, and well-formulated open questions in this area require some form of integration in a single forum. The ARW and the upcoming proceedings book with papers by the majority of the participants has provided this forum. The meeting was not planned as a continuation of the earlier NATO ASI in Rhodes in 1996, although several people have participated in both meetings.




Nanofluid Dynamics and Transport Phenomenon


Book Description

The text offers a detailed presentation of mathematical, numerical, and experimental techniques for nanofluids. It further covers the synthesis, characterization, stability, and heat transport. The book comprehensively discusses topics such as the comparison of heat transfer models, flow features of ternary hybrid nanofluids, thermodynamics and mass diffusion, and natural convection in triangular cavities. This book: Emphasizes the enhancement of heat transfer processes through nanoparticles, extending beyond heat transfer to applications in renewable energy. Explores the applications of nanofluids in enhancing food processing and agricultural practices. Covers thermal instability of couple-stress on viscous-elastic nanofluid flow and natural convection in a triangular cavity. Explains concepts including nanofluid-based energy storage, mass diffusion, thermodynamics, and nanofluid synthetic techniques. Presents topics such as numerical methods, fluid dynamics simulation, magnetohydrodynamics, heat and mass transfer, and radiation. It is primarily written for senior undergraduates, graduate students, and academic researchers in the fields of mechanical engineering, aerospace engineering, automotive engineering, industrial and production engineering, energy engineering, fluid dynamics, and tribology.




Gaseous Radiation Detectors


Book Description

Describes the fundamentals and applications of gaseous radiation detection, ideal for researchers and experimentalists in nuclear and particle physics.










Symmetry and Fluid Mechanics


Book Description

Since the 1980s, attention has increased in the research of fluid mechanics due to its wide application in industry and phycology. Major advances have occurred in the modeling of key topics such Newtonian and non-Newtonian fluids, nanoparticles, thermal management, and physiological fluid phenomena in biological systems, which have been published in this Special Issue on symmetry and fluid mechanics for Symmetry. Although, this book is not a formal textbook, it will be useful for university teachers, research students, and industrial researchers and for overcoming the difficulties that occur when considering the nonlinear governing equations. For such types of equations, obtaining an analytic or even a numerical solution is often more difficult. This book addresses this challenging job by outlining the latest techniques. In addition, the findings of the simulation are logically realistic and meet the standard of sufficient scientific value.




Dynamics of Nonlinear Waves in Dissipative Systems Reduction, Bifurcation and Stability


Book Description

The mathematical description of complex spatiotemporal behaviour observed in dissipative continuous systems is a major challenge for modern research in applied mathematics. While the behaviour of low-dimensional systems, governed by the dynamics of a finite number of modes is well understood, systems with large or unbounded spatial domains show intrinsic infinite-dimensional behaviour --not a priori accessible to the methods of finite dimensionaldynamical systems. The purpose of the four contributions in this book is to present some recent and active lines of research in evolution equations posed in large or unbounded domains. One of the most prominent features of these systems is the propagation of various types of patterns in the form of waves, such as travelling and standing waves and pulses and fronts. Different approaches to studying these kinds of phenomena are discussed in the book. A major theme is the reduction of an original evolution equation in the form of a partial differential equation system to a simpler system of equations, either a system of ordinary differential equation or a canonical system of PDEs. The study of the reduced equations provides insight into the bifurcations from simple to more complicated solutions and their stabilities. .