Li, Z C
2003-01-01
An artificial ordered layered structure of high energy was obtained by a form of ion beam manipulation, namely interface-assisted ion beam mixing, of appropriately designed nano-sized Ag-Pd multilayered films, in which the interfacial free energy elevated the Ag-Pd multilayered films to near to the corresponding highly energetic state. Diffraction analysis suggested that the ordered layered structure consisted of two overlapped face-centred-cubic lattices with lattice constants smaller than those of both pure Ag and pure Pd. The growth mechanism was also discussed in terms of a dynamic atomic collision, followed by a relaxation lasting for an extremely short time, involved in the irradiation process.
Li, Z. C.; Liu, B. X.
2003-03-01
An artificial ordered layered structure of high energy was obtained by a form of ion beam manipulation, namely interface-assisted ion beam mixing, of appropriately designed nano-sized Ag-Pd multilayered films, in which the interfacial free energy elevated the Ag-Pd multilayered films to near to the corresponding highly energetic state. Diffraction analysis suggested that the ordered layered structure consisted of two overlapped face-centred-cubic lattices with lattice constants smaller than those of both pure Ag and pure Pd. The growth mechanism was also discussed in terms of a dynamic atomic collision, followed by a relaxation lasting for an extremely short time, involved in the irradiation process.
Nonequilibrium Energetics of Single Molecule Motor, Kinesin-1
Ariga, Takayuki; Tomishige, Michio; Mizuno, Daisuke
2018-02-01
Molecular motors are nonequilibrium open systems that convert chemical energy to mechanical work. Here we investigate the nonequilibrium energetics of a single molecule kinesin by measuring the motion of an attached probe particle and its response to external forces with optical tweezers. The sum of the heat dissipation estimated from the violation of the fluctuation-response relation and the output power was inconsistent with the input free energy rate, implying that internal dissipation is dominant. By using a two-state Markov model, we discuss the energy flow of the kinesin motor.
Nonequilibrium Energetics of a Single F1-ATPase Molecule
Toyabe, Shoichi; Watanabe-Nakayama, Takahiro; Okamoto, Tetsuaki; Kudo, Seishi; Muneyuki, Eiro
2010-01-01
Molecular motors drive mechanical motions utilizing the free energy liberated from chemical reactions such as ATP hydrolysis. Although it is essential to know the efficiency of this free energy transduction, it has been a challenge due to the system's microscopic scale. Here, we evaluate the single-molecule energetics of a rotary molecular motor, F1-ATPase, by applying a recently derived nonequilibrium equality together with an electrorotation method. We show that the sum of the heat flow thr...
Effect of microstructure on the detonation initiation in energetic materials
Zhang, J.; Jackson, T. L.
2017-12-01
In this work we examine the role of the microstructure on detonation initiation of energetic materials. We solve the reactive Euler equations, with the energy equation augmented by a power deposition term. The deposition term is based on simulations of void collapse at the microscale, modeled at the mesoscale as hot-spots, while the reaction rate at the mesoscale is modeled using density-based kinetics. We carry out two-dimensional simulations of random packs of HMX crystals in a binder. We show that mean particle size, size distribution, and particle shape have a major effect on the transition between detonation and no-detonation, thus highlighting the importance of the microstructure for shock-induced initiation.
Non-equilibrium phonon generation and detection in microstructure devices
Hertzberg, J. B.
2011-01-01
We demonstrate a method to excite locally a controllable, non-thermal distribution of acoustic phonon modes ranging from 0 to ∼200 GHz in a silicon microstructure, by decay of excited quasiparticle states in an attached superconducting tunnel junction (STJ). The phonons transiting the structure ballistically are detected by a second STJ, allowing comparison of direct with indirect transport pathways. This method may be applied to study how different phonon modes contribute to the thermal conductivity of nanostructures. © 2011 American Institute of Physics.
Optimising mechanical behaviour of new advanced steels based on fine non-equilibrium microstructures
HajyAkbary, F.
2015-01-01
This Ph.D. thesis investigates the relation between microstructural and mechanical properties of Advanced High Strength Steels (AHSS), with the goal of developing a microstructure with optimised mechanical properties. Among different grades of AHSS, Quenching and Partitioning (Q&P) steel which is
Sagis, L.M.C.; Öttinger, H.C.
2013-01-01
In this paper we present a general model for the dynamic behavior of multiphase systems in which the bulk phases and interfaces have a complex microstructure (for example, immiscible polymer blends with added compatibilizers, or polymer stabilized emulsions with thickening agents dispersed in the
Piserchia, Andrea; Zerbetto, Mirco; Frezzato, Diego
2015-03-28
In this work we show that a non-equilibrium statistical tool based on Jarzynski's equality (JE) can be applied to achieve a sufficiently accurate mapping of the torsion free energy, bond-by-bond, for an alkyl thiol ligand tethered to a gold surface and sensing the presence of the surrounding cluster of similar chains. The strength of our approach is the employment of a strategy to let grow the internal energetics of the whole system (namely, the "energy morphing" stage recently presented by us in J. Comput. Chem., 2014, 35, 1865-1881) before initiating the rotational steering, which yields accurate results in terms of statistical uncertainties and bias on the free energy profiles. The work is mainly methodological and illustrates the feasibility of this kind of inspection on nanoscale molecular clusters with conformational flexibility. The outcomes for the archetype of self-assembled-monolayers considered here, a regular pattern of 10-carbon alkyl thiols on an ideal gold surface, give information on the conformational mobility of the ligands. Notably, such information is unlikely to be obtained by means of standard equilibrium techniques or by conventional molecular dynamics simulations.
Nonequilibrium synthesis of NbAl3 and Nb-Al-V alloys by laser cladding. I - Microstructure evolution
Sircar, S.; Chattopadhyay, K.; Mazumder, J.
1992-01-01
The evolution of the microstructure in NbAl3 synthesized by a laser cladding technique (a rapid solidification process, with cooling rates up to 10 exp 6 C/sec) is investigated, and the phases are identified using convergent beam electron diffraction. Two new metastable phases were identified and characterized in detail. The effect of adding V on the final microstructure was also investigated, and the various phase chemistries and the partitioning of different elements into different phases were studied.
Directory of Open Access Journals (Sweden)
M. K. Temgire
2012-01-01
Full Text Available Several microstructures are evolved at the interface when sparingly soluble solid surfactants come in contact with water. One class of these microstructures is termed as “myelin figures”; these were observed when phosphatidylcholine came in contact with water. Although the myelins are initially simple rod-like, complex forms like helices, coils and so forth. appear in the later stage. Finally, the myelins fuse together to form a complex mosaic-like structure. When studied by taking a cross-section using cryoscanning electron microscopy, it revealed concentric circular pattern inside the myelin figures. The cross-sections of (dioctyl sodium dodecyl sulfosiccinate AOT/water system myelin internal structures were lost. When p-toluenesulfonic acid (PTS 2 wt% was present in the water phase, AOT myelins revealed the internal microstructures. It has annular concentric ring-like structure with a core axon at the centre. Further investigation revealed new microstructures for the first time having multiple axons in the single-myelin strand.
Nonequilibrium Phase Chemistry in High Temperature Structure Alloys
Wang, R.
1991-01-01
Titanium and nickel aluminides of nonequilibrium microstructures and in thin gauge thickness were identified, characterized and produced for potential high temperature applications. A high rate sputter deposition technique for rapid surveillance of the microstructures and nonequilibrium phase is demonstrated. Alloys with specific compositions were synthesized with extended solid solutions, stable dispersoids, and specific phase boundaries associated with different heat treatments. Phase stability and mechanical behavior of these nonequilibrium alloys were investigated and compared.
Modeling interfacial dynamics using nonequilibrium thermodynamics frameworks
Sagis, L.M.C.
2013-01-01
In recent years several nonequilibrium thermodynamic frameworks have been developed capable of describing the dynamics of multiphase systems with complex microstructured interfaces. In this paper we present an overview of these frameworks. We will discuss interfacial dynamics in the context of the
Nonequilibrium molecular dynamics
Wm.G.Hoover; C.G.Hoover
2005-01-01
Nonequilibrium Molecular Dynamics is a powerful simulation tool. Like its equilibrium cousin, nonequilibrium molecular dynamics is based on time-reversible equations of motion. But unlike conventional mechanics, nonequilibrium molecular dynamics provides a consistent microscopic basis for the irreversible macroscopic Second Law of Thermodynamics. We recall here how fast computers led to the development of nonequilibrium molecular dynamics from the statistical mechanics of the 1950s. Computer-...
Multiscale Modeling of Grain Boundaries in ZrB2: Structure, Energetics, and Thermal Resistance
Lawson, John W.; Daw, Murray S.; Squire, Thomas H.; Bauschlicher, Charles W., Jr.
2012-01-01
A combination of ab initio, atomistic and finite element methods (FEM) were used to investigate the structures, energetics and lattice thermal conductance of grain boundaries for the ultra high temperature ceramic ZrB2. Atomic models of idealized boundaries were relaxed using density functional theory. Information about bonding across the interfaces was determined from the electron localization function. The Kapitza conductance of larger scale versions of the boundary models were computed using non-equilibrium molecular dynamics. The interfacial thermal parameters together with single crystal thermal conductivities were used as parameters in microstructural computations. FEM meshes were constructed on top of microstructural images. From these computations, the effective thermal conductivity of the polycrystalline structure was determined.
Federal Laboratory Consortium — The Energetic Systems Division provides full-spectrum energetic engineering services (project management, design, analysis, production support, in-service support,...
Nonequilibrium molecular dynamics
Directory of Open Access Journals (Sweden)
Wm.G.Hoover
2005-01-01
Full Text Available Nonequilibrium Molecular Dynamics is a powerful simulation tool. Like its equilibrium cousin, nonequilibrium molecular dynamics is based on time-reversible equations of motion. But unlike conventional mechanics, nonequilibrium molecular dynamics provides a consistent microscopic basis for the irreversible macroscopic Second Law of Thermodynamics. We recall here how fast computers led to the development of nonequilibrium molecular dynamics from the statistical mechanics of the 1950s. Computer-based theories facilitated revolutionary breakthroughs in understanding during the 1970s and 1980s. The new idea key to the nonequilibrium development was the replacement of the external thermodynamic environment by internal control variables. The new variables can control temperature, or pressure, or energy, or stress, or heat flux. These thermostat, barostat, ergostat, ... variables can control and maintain nonequilibrium states. We illustrate the methods with a simple example well-suited to student exploration, a thermostatted harmonic oscillator exposed to a temperature gradient.
DEFF Research Database (Denmark)
Pantleon, Karen; Somers, Marcel A. J.
2010-01-01
Electrodeposition results in a non-equilibrium state of the as-deposited nanocrystalline microstructure, which evolves towards an energetically more favorable state as a function of time and/or temperature upon deposition. Real-time investigation of the evolving microstructure in copper, silver......-annealing kinetics of copper and silver electrodeposits as well as the annealing kinetics of electrodeposited nickel. Similarities and characteristic differences of the kinetics and mechanisms of microstructure evolution in the various electrodeposits are discussed and the experimental results are attempted...... and nickel electrodeposits was achieved by time-resolved X-ray diffraction line profile analysis and crystallographic texture analysis during room temperature storage and during isothermal annealing at elevated temperatures. These in-situ studies with unique time resolution allowed quantification of the self...
Stochastic Energetics of Quantum Transport
Ghosh, Pulak Kumar; Ray, Deb Shankar
2006-01-01
We examine the stochastic energetics of directed quantum transport due to rectification of non-equilibrium thermal fluctuations. We calculate the quantum efficiency of a ratchet device both in presence and absence of an external load to characterize two quantifiers of efficiency. It has been shown that the quantum current as well as efficiency in absence of load (Stokes efficiency) is higher as compared to classical current and efficiency, respectively, at low temperature. The conventional ef...
Nonequilibrium molecular dynamics
Energy Technology Data Exchange (ETDEWEB)
Hoover, W.G. (California Univ., Davis, CA (USA). Dept. of Applied Science Lawrence Livermore National Lab., CA (USA))
1990-11-01
The development of nonequilibrium molecular dynamics is described, with emphasis on massively-parallel simulations involving the motion of millions, soon to be billions, of atoms. Corresponding continuum simulations are also discussed. 14 refs., 8 figs.
Nonequilibrium statistical physics
Röpke, Gerd
2013-01-01
Authored by one of the top theoretical physicists in Germany, and a well-known authority in the field, this is the only coherent presentation of the subject suitable for masters and PhD students, as well as postdocs in physics and related disciplines.Starting from a general discussion of the nonequilibrium state, different standard approaches such as master equations, and kinetic and linear response theory, are derived after special assumptions. This allows for an insight into the problems of nonequilibrium physics, a discussion of the limits, and suggestions for improvements. Applications
Energy Technology Data Exchange (ETDEWEB)
Brown, Judith A.; Zikry, M. A., E-mail: zikry@ncsu.edu [Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, North Carolina 27695-7910 (United States)
2015-09-28
The coupled electromagnetic (EM)-thermo-mechanical response of cyclotrimethylenetrinitramine-estane energetic aggregates under laser irradiation and high strain rate loads has been investigated for various aggregate sizes and binder volume fractions. The cyclotrimethylenetrinitramine (RDX) crystals are modeled with a dislocation density-based crystalline plasticity formulation and the estane binder is modeled with finite viscoelasticity through a nonlinear finite element approach that couples EM wave propagation with laser heat absorption, thermal conduction, and inelastic deformation. Material property and local behavior mismatch at the crystal-binder interfaces resulted in geometric scattering of the EM wave, electric field and laser heating localization, high stress gradients, dislocation density, and crystalline shear slip accumulation. Viscous sliding in the binder was another energy dissipation mechanism that reduced stresses in aggregates with thicker binder ligaments and larger binder volume fractions. This investigation indicates the complex interactions between EM waves and mechanical behavior, for accurate predictions of laser irradiation of heterogeneous materials.
Nonequilibrium thermodynamics of nucleation
Schweizer, M.; Sagis, L.M.C.
2014-01-01
We present a novel approach to nucleation processes based on the GENERIC framework (general equation for the nonequilibrium reversible-irreversible coupling). Solely based on the GENERIC structure of time-evolution equations and thermodynamic consistency arguments of exchange processes between a
Statistical mechanics of nonequilibrium liquids
Evans, Denis J; Craig, D P; McWeeny, R
1990-01-01
Statistical Mechanics of Nonequilibrium Liquids deals with theoretical rheology. The book discusses nonlinear response of systems and outlines the statistical mechanical theory. In discussing the framework of nonequilibrium statistical mechanics, the book explains the derivation of a nonequilibrium analogue of the Gibbsian basis for equilibrium statistical mechanics. The book reviews the linear irreversible thermodynamics, the Liouville equation, and the Irving-Kirkwood procedure. The text then explains the Green-Kubo relations used in linear transport coefficients, the linear response theory,
International Nuclear Information System (INIS)
2012-01-01
This report explains the energetic map of Uruguay as well as the different systems that delimits political frontiers in the region. The electrical system importance is due to the electricity, oil and derived , natural gas, potential study, biofuels, wind and solar energy
Non-equilibrium thermodynamics
De Groot, Sybren Ruurds
1984-01-01
The study of thermodynamics is especially timely today, as its concepts are being applied to problems in biology, biochemistry, electrochemistry, and engineering. This book treats irreversible processes and phenomena - non-equilibrium thermodynamics.S. R. de Groot and P. Mazur, Professors of Theoretical Physics, present a comprehensive and insightful survey of the foundations of the field, providing the only complete discussion of the fluctuating linear theory of irreversible thermodynamics. The application covers a wide range of topics: the theory of diffusion and heat conduction, fluid dyn
The nonequilibrium molecular dynamics
International Nuclear Information System (INIS)
Hoover, W.G.
1992-03-01
MOLECULAR DYNAMICS has been generalized in order to simulate a variety of NONEQUILIBRIUM systems. This generalization has been achieved by adopting microscopic mechanical definitions of macroscopic thermodynamic and hydrodynamic variables, such as temperature and stress. Some of the problems already treated include rapid plastic deformation, intense heat conduction, strong shockwaves simulation, and far-from-equilibrium phase transformations. Continuing advances in technique and in the modeling of interatomic forces, coupled with qualitative improvements in computer hardware, are enabling such simulations to approximate real-world microscale and nanoscale experiments
Energetic Tuning in Spirocyclic Conjugated Polymers
Hugo Bronstein; Frank D. King
2016-01-01
Precise control of the energy levels in a conjugated polymer is the key to allowing their exploitation in optoelectronic devices. The introduction of spirocycles into conjugated polymers has traditionally been used to enhance their solid state microstructure. Here we present a highly novel method of energetic tuning through the use of electronically active spirocyclic systems. By modifying the size and oxidation state of a heteroatom in an orthogonal spirocycle we demonstrate energetic fine t...
Directory of Open Access Journals (Sweden)
Katalin Martinás
2007-02-01
Full Text Available A microeconomic, agent based framework to dynamic economics is formulated in a materialist approach. An axiomatic foundation of a non-equilibrium microeconomics is outlined. Economic activity is modelled as transformation and transport of commodities (materials owned by the agents. Rate of transformations (production intensity, and the rate of transport (trade are defined by the agents. Economic decision rules are derived from the observed economic behaviour. The non-linear equations are solved numerically for a model economy. Numerical solutions for simple model economies suggest that the some of the results of general equilibrium economics are consequences only of the equilibrium hypothesis. We show that perfect competition of selfish agents does not guarantee the stability of economic equilibrium, but cooperativity is needed, too.
Microstructure of irradiated materials
International Nuclear Information System (INIS)
Robertson, I.M.
1995-01-01
The focus of the symposium was on the changes produced in the microstructure of metals, ceramics, and semiconductors by irradiation with energetic particles. the symposium brought together those working in the different material systems, which revealed that there are a remarkable number of similarities in the irradiation-produced microstructures in the different classes of materials. Experimental, computational and theoretical contributions were intermixed in all of the sessions. This provided an opportunity for these groups, which should interact, to do so. Separate abstracts were prepared for 58 papers in this book
Inflation and nonequilibrium renormalization group
International Nuclear Information System (INIS)
Zanella, Juan; Calzetta, Esteban
2007-01-01
We study the spectrum of primordial fluctuations and the scale dependence of the inflaton spectral index due to self-interactions of the field. We compute the spectrum of fluctuations by applying nonequilibrium renormalization group techniques
Enrique, R A; Averback, R S; Bellon, P
2003-01-01
Alloys under irradiation are continuously driven away from equilibrium: Every time an external particle interacts with the atoms in the solid, a perturbation very localized in space and time is produced. Under this external forcing, phase and microstructural evolution depends ultimately on the dynamical interaction between the external perturbation and the internal recovery kinetics of the alloy. We consider the nonequilibrium steady state of an immiscible binary alloy subject to mixing by heavy-ion irradiation. It has been found that the range of the forced atomic relocations taking place during collision cascades plays an important role on the final microstructure: when this range is large enough, it can lead to the spontaneous formation of compositional patterns at the nanometer scale. These results were rationalized in the framework of a continuum model solved by deriving a nonequilibrium thermodynamic potential. Here we derive the nonequilibrium structure factor by including the role of fluctuations. In ...
Anisotropic nonequilibrium hydrodynamic attractor
Strickland, Michael; Noronha, Jorge; Denicol, Gabriel S.
2018-02-01
We determine the dynamical attractors associated with anisotropic hydrodynamics (aHydro) and the DNMR equations for a 0 +1 d conformal system using kinetic theory in the relaxation time approximation. We compare our results to the nonequilibrium attractor obtained from the exact solution of the 0 +1 d conformal Boltzmann equation, the Navier-Stokes theory, and the second-order Mueller-Israel-Stewart theory. We demonstrate that the aHydro attractor equation resums an infinite number of terms in the inverse Reynolds number. The resulting resummed aHydro attractor possesses a positive longitudinal-to-transverse pressure ratio and is virtually indistinguishable from the exact attractor. This suggests that an optimized hydrodynamic treatment of kinetic theory involves a resummation not only in gradients (Knudsen number) but also in the inverse Reynolds number. We also demonstrate that the DNMR result provides a better approximation of the exact kinetic theory attractor than the Mueller-Israel-Stewart theory. Finally, we introduce a new method for obtaining approximate aHydro equations which relies solely on an expansion in the inverse Reynolds number. We then carry this expansion out to the third order, and compare these third-order results to the exact kinetic theory solution.
Nonequilibrium 1/f γ noise in conducting films and contacts
International Nuclear Information System (INIS)
Zhigal'skii, Gennadii P
2003-01-01
Work on nonequilibrium flicker-noise (1/f γ noise or NEFN) in conducting films of various materials and in thin-film contacts is reviewed. Experimental methods for studying nonequilibrium flicker fluctuations by separating NEFN from the total noise are suggested. Published results on NEFN in metal and alloy films, Ni/Cr-film and Ta x N y -film resistors, and contacts are systematized. It is shown that various kinds of NEFN occur in conducting films. Depending on test conditions, external influences, and the film microstructure, both stationary and non-stationary NEFNs are observed. The use of 1/f γ noise measurements for nondestructively controlling the quality of thin-film conductors is substantiated. For most of the passive IC components (thin-film conductors, resistive layers, contacts), NEFN makes a much more informative quality indicator than equilibrium flicker-noise. (reviews of topical problems)
Evolution of phase microstructure during irradiation
International Nuclear Information System (INIS)
Wiedersich, H.
1985-11-01
The phase microstructure of alloys is frequently severely altered during irradiation. Sluggish precipitation reactions including precipitation coarsening are accelerated by irradiation-enhanced diffusion. Radiation-induced segregation redistributes existing precipitate phases within the microstructure, induces precipitation of nonequilibrium phases and affects the composition of phases in multicomponent alloys. The displacement process causes disordering of ordered alloys and frequently amorphization, especially in intermetallic compounds, at low temperature. Although a good qualitative understanding of the basic process involved, i.e., displacement mixing, radiation-enhanced diffusion and radiation-induced segregation exists, methods for detailed quantitative modeling of the evolution of the microstructure of alloys remain to be developed
Nonequilibrium thermodynamics of an interface
Schweizer, Marco; Öttinger, Hans Christian; Savin, Thierry
2016-05-01
Interfacial thermodynamics has deep ramifications in understanding the boundary conditions of transport theories. We present a formulation of local equilibrium for interfaces that extends the thermodynamics of the "dividing surface," as introduced by Gibbs, to nonequilibrium settings such as evaporation or condensation. By identifying the precise position of the dividing surface in the interfacial region with a gauge degree of freedom, we exploit gauge-invariance requirements to consistently define the intensive variables for the interface. The model is verified under stringent conditions by employing high-precision nonequilibrium molecular-dynamics simulations of a coexisting vapor-liquid Lennard-Jones fluid. We conclude that the interfacial temperature is determined using the surface tension as a "thermometer," and it can be significantly different from the temperatures of the adjacent phases. Our findings lay foundations for nonequilibrium interfacial thermodynamics.
Non-equilibrium phase transitions
Henkel, Malte; Lübeck, Sven
2009-01-01
This book describes two main classes of non-equilibrium phase-transitions: (a) static and dynamics of transitions into an absorbing state, and (b) dynamical scaling in far-from-equilibrium relaxation behaviour and ageing. The first volume begins with an introductory chapter which recalls the main concepts of phase-transitions, set for the convenience of the reader in an equilibrium context. The extension to non-equilibrium systems is made by using directed percolation as the main paradigm of absorbing phase transitions and in view of the richness of the known results an entire chapter is devoted to it, including a discussion of recent experimental results. Scaling theories and a large set of both numerical and analytical methods for the study of non-equilibrium phase transitions are thoroughly discussed. The techniques used for directed percolation are then extended to other universality classes and many important results on model parameters are provided for easy reference.
Open problems in non-equilibrium physics
Energy Technology Data Exchange (ETDEWEB)
Kusnezov, D.
1997-09-22
The report contains viewgraphs on the following: approaches to non-equilibrium statistical mechanics; classical and quantum processes in chaotic environments; classical fields in non-equilibrium situations: real time dynamics at finite temperature; and phase transitions in non-equilibrium conditions.
Microstructure of rapidly solidified materials
Jones, H.
1984-07-01
The basic features of rapidly solidified microstructures are described and differences arising from alternative processing strategies are discussed. The possibility of achieving substantial undercooling prior to solidification in processes such as quench atomization and chill block melt spinning can give rise to striking microstructural transitions even when external heat extraction is nominally Newtonian. The increased opportunity in laser and electron beam surface melting for epitaxial growth on the parent solid at an accelerating rate, however, does not exclude the formation of nonequilibrium phases since the required undercooling can be locally attained at the solidification front which is itself advancing at a sufficiently high velocity. The effects of fluid flow indicated particularly in melt spinning and surface melting are additional to the transformational and heat flow considerations that form the present basis for interpretation of such microstructural effects.
Computer simulation of nonequilibrium processes
International Nuclear Information System (INIS)
Hoover, W.G.; Moran, B.; Holian, B.L.; Posch, H.A.; Bestiale, S.
1987-01-01
Recent atomistic simulations of irreversible macroscopic hydrodynamic flows are illustrated. An extension of Nose's reversible atomistic mechanics makes it possible to simulate such non-equilibrium systems with completely reversible equations of motion. The new techniques show that macroscopic irreversibility is a natural inevitable consequence of time-reversible Lyapunov-unstable microscopic equations of motion
Non-equilibrium supramolecular polymerization.
Sorrenti, Alessandro; Leira-Iglesias, Jorge; Markvoort, Albert J; de Greef, Tom F A; Hermans, Thomas M
2017-09-18
Supramolecular polymerization has been traditionally focused on the thermodynamic equilibrium state, where one-dimensional assemblies reside at the global minimum of the Gibbs free energy. The pathway and rate to reach the equilibrium state are irrelevant, and the resulting assemblies remain unchanged over time. In the past decade, the focus has shifted to kinetically trapped (non-dissipative non-equilibrium) structures that heavily depend on the method of preparation (i.e., pathway complexity), and where the assembly rates are of key importance. Kinetic models have greatly improved our understanding of competing pathways, and shown how to steer supramolecular polymerization in the desired direction (i.e., pathway selection). The most recent innovation in the field relies on energy or mass input that is dissipated to keep the system away from the thermodynamic equilibrium (or from other non-dissipative states). This tutorial review aims to provide the reader with a set of tools to identify different types of self-assembled states that have been explored so far. In particular, we aim to clarify the often unclear use of the term "non-equilibrium self-assembly" by subdividing systems into dissipative, and non-dissipative non-equilibrium states. Examples are given for each of the states, with a focus on non-dissipative non-equilibrium states found in one-dimensional supramolecular polymerization.
Rheology via nonequilibrium molecular dynamics
International Nuclear Information System (INIS)
Hoover, W.G.
1982-10-01
The equilibrium molecular dynamics formulated by Newton, Lagrange, and Hamilton has been modified in order to simulate rheologial molecular flows with fast computers. This modified Nonequilibrium Molecular Dynamics (NEMD) has been applied to fluid and solid deformations, under both homogeneous and shock conditions, as well as to the transport of heat. The irreversible heating associated with dissipation could be controlled by carrying out isothermal NEMD calculations. The new isothermal NEMD equations of motion are consistent with Gauss' 1829 Least-Constraint principle as well as certain microscopic equilibrium and nonequilibrium statistical formulations due to Gibbs and Boltzmann. Application of isothermal NEMD revealed high-frequency and high-strain-rate behavior for simple fluids which resembled the behavior of polymer solutions and melts at lower frequencies and strain rates. For solids NEMD produces plastic flows consistent with experimental observations at much lower strain rates. The new nonequilibrium methods also suggest novel formulations of thermodynamics in nonequilibrium systems and shed light on the failure of the Principle of Material Frame Indifference
Energetics Conditioning Facility
Federal Laboratory Consortium — The Energetics Conditioning Facility is used for long term and short term aging studies of energetic materials. The facility has 10 conditioning chambers of which 2...
Nonequilibrium quantum fluctuations of work.
Allahverdyan, A E
2014-09-01
The concept of work is basic for statistical thermodynamics. To gain a fuller understanding of work and its (quantum) features, it needs to be represented as an average of a fluctuating quantity. Here I focus on the work done between two moments of time for a thermally isolated quantum system driven by a time-dependent Hamiltonian. I formulate two natural conditions needed for the fluctuating work to be physically meaningful for a system that starts its evolution from a nonequilibrium state. The existing definitions do not satisfy these conditions due to issues that are traced back to noncommutativity. I propose a definition of fluctuating work that is free of previous drawbacks and that applies for a wide class of nonequilibrium initial states. It allows the deduction of a generalized work-fluctuation theorem that applies for an arbitrary (out-of-equilibrium) initial state.
Microstructure evolution during irradiation
International Nuclear Information System (INIS)
Robertson, I.M.; Was, G.S.; Hobbs, L.W.; Diaz de la Rubia, T.
1997-01-01
The symposium focused on the microstructural changes produced in semiconductors, metals, ceramics and polymers by irradiation with energetic particles. The symposium provided an opportunity to bring together those working in different materials systems and revealed that there are a remarkable number of similarities in the changes produced by irradiation in the different classes of materials. Experimental, computational and theoretical contributions were intermixed throughout the sessions, which provided an opportunity for these groups to interact. Separate abstracts were prepared for most papers in this volume
Computer simulation of nonequilibrium processes
Energy Technology Data Exchange (ETDEWEB)
Wallace, D.C.
1985-07-01
The underlying concepts of nonequilibrium statistical mechanics, and of irreversible thermodynamics, will be described. The question at hand is then, how are these concepts to be realize in computer simulations of many-particle systems. The answer will be given for dissipative deformation processes in solids, on three hierarchical levels: heterogeneous plastic flow, dislocation dynamics, an molecular dynamics. Aplication to the shock process will be discussed.
Manipulating nonequilibrium magnetism through superconductors.
Giazotto, Francesco; Taddei, Fabio; Fazio, Rosario; Beltram, Fabio
2005-08-05
Electrostatic control of the magnetization of a normal mesoscopic conductor is analyzed in a hybrid superconductor-normal-conductor-superconductor system. This effect stems from the interplay between the nonequilibrium condition in the normal region and the Zeeman splitting of the quasi-particle density of states of the superconductor subjected to a static in-plane magnetic field. Unexpected spin-dependent effects such as magnetization suppression, diamagnetic-like response of the susceptibility, as well as spin-polarized current generation are the most remarkable features presented. The impact of scattering events is evaluated and lets us show that this effect is compatible with realistic material properties and fabrication techniques.
Nonequilibrium theory of flame propagation
International Nuclear Information System (INIS)
Merzhanov, A.G.
1995-01-01
The nonequilibrium theory of flame propagation is considered as applied to the following three processes of wave propagation: the combustion waves of the second kind, the combustion waves with broad reaction zones, and the combustion waves with chemical stages. Kinetic and combustion wave parameters are presented for different in composition mixtures of boron and transition metals, such as Zr, Hf, Ti, Nb, Ta, Mo, as well as for the Ta-N, Zr-C-H, Nb-B-O systems to illustrate specific features of the above-mentioned processes [ru
Energy repartition in the nonequilibrium steady state
Yan, Peng; Bauer, G.E.; Zhang, Huaiwu
2017-01-01
The concept of temperature in nonequilibrium thermodynamics is an outstanding theoretical issue. We propose an energy repartition principle that leads to a spectral (mode-dependent) temperature in steady-state nonequilibrium systems. The general concepts are illustrated by analytic solutions of
Non-dissipative effects in nonequilibrium systems
Maes, Christian
2018-01-01
This book introduces and discusses both the fundamental aspects and the measurability of applications of time-symmetric kinetic quantities, outlining the features that constitute the non-dissipative branch of non-equilibrium physics. These specific features of non-equilibrium dynamics have largely been ignored in standard statistical mechanics texts. This introductory-level book offers novel material that does not take the traditional line of extending standard thermodynamics to the irreversible domain. It shows that although stationary dissipation is essentially equivalent with steady non-equilibrium and ubiquitous in complex phenomena, non-equilibrium is not determined solely by the time-antisymmetric sector of energy-entropy considerations. While this should not be very surprising, this book provides timely, simple reminders of the role of time-symmetric and kinetic aspects in the construction of non-equilibrium statistical mechanics.
Morphological effects on sensitivity of heterogeneous energetic materials
Roy, Sidhartha; Rai, Nirmal; Sen, Oishik; Udaykumar, H. S.
2017-06-01
The mesoscale physical response under shock loading in heterogeneous energetics is inherently linked to the microstructural characteristics. The current work demonstrates the connection between the microstructural features of porous energetic material and its sensitivity. A unified levelset based framework is developed to characterize the microstructures of a given sample. Several morphological metrics describing the mesoscale geometry of the materials are extracted using the current tool including anisotropy, tortuosity, surface to volume, nearest neighbors, size and curvature distributions. The relevant metrics among the ones extracted are identified and correlated to the mesoscale response of the energetic materials under shock loading. Two classes of problems are considered here: (a) field of idealized voids embedded in the HMX material and (b) real samples of pressed HMX. The effects of stochasticity associated with void arrangements on the sensitivity of the energetic material samples are shown. In summary, this work demonstrates the relationship between the mesoscale morphology and shock response of heterogeneous energetic materials using a levelset based framework.
Microstructure modeling in weld metal
International Nuclear Information System (INIS)
David, S.A.; Babu, S.S.
1995-01-01
Since microstructure development in the weld metal region is controlled by various physical processes, there is a need for integrated predictive models based on fundamental principles to describe and predict the effect of these physical processes. These integrated models should be based on various tools available for modeling microstructure development in a wide variety of alloy systems and welding processes. In this paper, the principles, methodology, and future directions of modeling thermochemical reactions in liquid, solidification, and solid state transformations are discussed with some examples for low-alloy steel, stainless steel, and Ni-base superalloy. Thermochemical deoxidation reactions in liquid low-alloy steel lead to oxide inclusion formation. This inclusion formation has been modeled by combining principles of ladle metallurgy and overall transformation kinetics. The model's comparison with the experimental data and the ongoing work on coupling this inclusion model with the numerical models of heat transfer and fluid flow are discussed. Also, recent advances in theoretical and physical modeling of the solidification process are reviewed with regard to predicting the solidification modes, grain structure development, segregation effects, and nonequilibrium solidification in welds. The effects of solid state phase transformations on microstructure development and various methods of modeling these transformations are reviewed. Successful models, based on diffusion-controlled growth and plate growth theories, on microstructure development in low-alloy steel and stainless steel weld metals are outlined. This paper also addresses the importance of advanced analytical techniques to understand the solid state transformation mechanisms in welds
Zandvliet, Henricus J.W.
2000-01-01
A classical thermodynamic description of a surface requires the introduction of a number of energetic parameters related to the surface steps. These parameters are the step free energy, the kink creation energy, and the energetic and entropic interactions between steps. This review will demonstrate
INTRODUCTION: Nonequilibrium Processes in Plasmas
Petrović, Zoran; Marić, Dragana; Malović, Gordana
2009-07-01
This book aims to give a cross section from a wide range of phenomena that, to different degrees, fall under the heading of non-equilibrium phenomenology. The selection is, of course, biased by the interests of the members of the scientific committee and of the FP6 Project 026328 IPB-CNP Reinforcing Experimental Centre for Non-equilibrium Studies with Application in Nano-technologies, Etching of Integrated Circuits and Environmental Research. Some of the papers included here are texts based on selected lectures presented at the Second International Workshop on Non-equilibrium Processes in Plasmas and Environmental Science. However, this volume is not just the proceedings of that conference as it contains a number of papers from authors that did not attend the conference. The goal was to put together a volume that would cover the interests of the project and support further work. It is published in the Institute of Physics journal Journal of Physics: Conference Series to ensure a wide accessibility of the articles. The texts presented here range from in-depth reviews of the current status and past achievements to progress reports of currently developed experimental devices and recently obtained still unpublished results. All papers have been refereed twice, first when speakers were selected based on their reputation and recently published results, and second after the paper was submitted both by the editorial board and individual assigned referees according to the standards of the conference and of the journal. Nevertheless, we still leave the responsibility (and honours) for the contents of the papers to the authors. The papers in this book are review articles that give a summary of the already published work or present the work in progress that will be published in full at a later date (or both). In the introduction to the first volume, in order to show how far reaching, ubiquitous and important non-equilibrium phenomena are, we claimed that ever since the early
Nonequilibrium fluctuations in a resistor.
Garnier, N; Ciliberto, S
2005-06-01
In small systems where relevant energies are comparable to thermal agitation, fluctuations are of the order of average values. In systems in thermodynamical equilibrium, the variance of these fluctuations can be related to the dissipation constant in the system, exploiting the fluctuation-dissipation theorem. In nonequilibrium steady systems, fluctuations theorems (FT) additionally describe symmetry properties of the probability density functions (PDFs) of the fluctuations of injected and dissipated energies. We experimentally probe a model system: an electrical dipole driven out of equilibrium by a small constant current I, and show that FT are experimentally accessible and valid. Furthermore, we stress that FT can be used to measure the dissipated power P = R I2 in the system by just studying the PDFs' symmetries.
Magnetic topology, nonequilibrium, and dissipation
International Nuclear Information System (INIS)
Parker, E.N.
1985-01-01
Static equilibrium of a magnetic field throughout a large volume of highly conducting fluid requires a degree of topological symmetry that is generally lacking in nature. The dynamical nonequilibrium of the magnetic topologies in the real world forms current sheets across which there is active reconnection of the field, dissipating the energy of the magnetic strains and reducing the fields toward simpler forms. The magnetic fields in astronomical settings are generally subject to continual straining by the convection within their parent body. The work done on the field by the convection appears in the energy of the small-scale strains, and is soon dissipated by the reconnection. The intense heating of the tenuous outer atmosphere of stars by this mechanism appears to be responsible for most of the X-ray emission of ordinary stars
Statistical thermodynamics of nonequilibrium processes
Keizer, Joel
1987-01-01
The structure of the theory ofthermodynamics has changed enormously since its inception in the middle of the nineteenth century. Shortly after Thomson and Clausius enunciated their versions of the Second Law, Clausius, Maxwell, and Boltzmann began actively pursuing the molecular basis of thermo dynamics, work that culminated in the Boltzmann equation and the theory of transport processes in dilute gases. Much later, Onsager undertook the elucidation of the symmetry oftransport coefficients and, thereby, established himself as the father of the theory of nonequilibrium thermodynamics. Com bining the statistical ideas of Gibbs and Langevin with the phenomenological transport equations, Onsager and others went on to develop a consistent statistical theory of irreversible processes. The power of that theory is in its ability to relate measurable quantities, such as transport coefficients and thermodynamic derivatives, to the results of experimental measurements. As powerful as that theory is, it is linear and...
International Nuclear Information System (INIS)
Sivintsev, Yu.V.
2001-01-01
Data on the current state and development of the nuclear energetics of Japan are reviewed. Preference of the strategy of tolerant development of the nuclear energetics of Japan including creation of the power nuclear energetics with the closed nuclear fuel cycle is noted. Realization and development of the program for the creating fast breeder reactor will provide to achieve total independence from import of any types of energy carriers including the fuel for nuclear fuel cycle. Scientific elaborations in Japan are conjectured the correlation of different types of fuel (oxide, metal, nitride), energy carriers (sodium, heavy metals, gas and water) and reactor power (large NPP, middle and small power plants) [ru
DEFF Research Database (Denmark)
Hansen, N.; Huang, X.; Hughes, D.A.
2004-01-01
Microstructural characterization and modeling has shown that a variety of metals deformed by different thermomechanical processes follows a general path of grain subdivision, by dislocation boundaries and high angle boundaries. This subdivision has been observed to very small structural scales...
Referesher Course on Contemporary Non-Equilibrium ...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 7. Referesher Course on Contemporary Non-Equilibrium Thermodynamics and Statistical Mechanics. Information and Announcements Volume 15 Issue 7 July 2010 pp 678-678 ...
Nonequilibrium molecular dynamics: The first 25 years
International Nuclear Information System (INIS)
Hoover, W.G.
1992-08-01
Equilibrium Molecular Dynamics has been generalized to simulate Nonequilibrium systems by adding sources of thermodynamic heat and work. This generalization incorporates microscopic mechanical definitions of macroscopic thermodynamic and hydrodynamic variables, such as temperature and stress, and augments atomistic forces with special boundary, constraint, and driving forces capable of doing work on, and exchanging heat with, an otherwise Newtonian system. The underlying Lyapunov instability of these nonequilibrium equations of motion links microscopic time-reversible deterministic trajectories to macroscopic time-irreversible hydrodynamic behavior as described by the Second Law of Thermodynamics. Green-Kubo linear-response theory has been checked. Nonlinear plastic deformation, intense heat conduction, shockwave propagation, and nonequilibrium phase transformation have all been simulated. The nonequilibrium techniques, coupled with qualitative improvements in parallel computer hardware, are enabling simulations to approximate real-world microscale and nanoscale experiments
Nonequilibrium Green's functions approach to inhomogeneous systems
Balzer, Karsten
2013-01-01
This book offers a self-contained introduction to non-equilibrium quantum particle dynamics for inhomogeneous systems, including a survey of recent breakthroughs pioneered by the authors and others. The approach is based on real-time Green's functions.
Non-equilibrium dog-flea model
Ackerson, Bruce J.
2017-11-01
We develop the open dog-flea model to serve as a check of proposed non-equilibrium theories of statistical mechanics. The model is developed in detail. Then it is applied to four recent models for non-equilibrium statistical mechanics. Comparison of the dog-flea solution with these different models allows checking claims and giving a concrete example of the theoretical models.
Plasma wave instabilities in nonequilibrium graphene
DEFF Research Database (Denmark)
Aryal, Chinta M.; Hu, Ben Yu-Kuang; Jauho, Antti-Pekka
2016-01-01
We study two-stream instabilities in a nonequilibrium system in which a stream of electrons is injected into doped graphene. As with equivalent nonequilibrium parabolic band systems, we find that the graphene systems can support unstable charge-density waves whose amplitudes grow with time. We...... of the injected electrons that maximizes the growth rate increases with increasing | q |. We compare the range and strength of the instability in graphene to that of two- and three-dimensional parabolic band systems....
Energetics Laboratory Facilities
Federal Laboratory Consortium — These energetic materials laboratories are equipped with explosion proof hoods with blow out walls for added safety, that are certified for safe handling of primary...
Role of Sink Density in Nonequilibrium Chemical Redistribution in Alloys
Martínez, Enrique; Senninger, Oriane; Caro, Alfredo; Soisson, Frédéric; Nastar, Maylise; Uberuaga, Blas P.
2018-03-01
Nonequilibrium chemical redistribution in open systems submitted to external forces, such as particle irradiation, leads to changes in the structural properties of the material, potentially driving the system to failure. Such redistribution is controlled by the complex interplay between the production of point defects, atomic transport rates, and the sink character of the microstructure. In this work, we analyze this interplay by means of a kinetic Monte Carlo (KMC) framework with an underlying atomistic model for the Fe-Cr model alloy to study the effect of ideal defect sinks on Cr concentration profiles, with a particular focus on the role of interface density. We observe that the amount of segregation decreases linearly with decreasing interface spacing. Within the framework of the thermodynamics of irreversible processes, a general analytical model is derived and assessed against the KMC simulations to elucidate the structure-property relationship of this system. Interestingly, in the kinetic regime where elimination of point defects at sinks is dominant over bulk recombination, the solute segregation does not directly depend on the dose rate but only on the density of sinks. This model provides new insight into the design of microstructures that mitigate chemical redistribution and improve radiation tolerance.
Nonequilibrium quantum meson gas: Dimensional reduction
Alvarez-Estrada, R. F.
2009-07-01
A nonequilibrium quantum gas of interacting relativistic effective mesons, ressembling qualitatively those produced in a heavy-ion collision, is described by a scalar φ^{{4}}_{} quantum field in (1 + 3) -dimensional Minkowski space. For high temperature and large temporal and spatial scales, we justify that classical statistical mechanics including quantum renormalization effects describe approximately the gas: nonequilibrium dimensional reduction (NEDR). As a source of hints, we treat the gas at equilibrium in real-time formalism and obtain simplifications for high temperature and large spatial scales, thereby extending a useful equilibrium dimensional reduction known for the imaginary-time formalism. By assumption, the nonequilibrium initial state of the gas, not far from thermal equilibrium, includes interactions and inhomogeneities. We use nonequilibrium real-time generating functionals and correlators at nonzero temperature. In the NEDR regime, our arguments yield: 1) renormalized correlators simplify, 2) the perturbative series for those simplified correlators can be resummed into a new nonequilibrium generating functional, Z’ r, dr , which is super-renormalizable and includes renormalization effects (large position-dependent thermal self-energies and effective couplings). Z’ r, dr could enable to study nonperturbatively changes in the phase structures of the field, by proceeding from the nonequilibrium quantum regime to the NEDR one.
Aerospace Applications of Non-Equilibrium Plasma
Blankson, Isaiah M.
2016-01-01
Nonequilibrium plasma/non-thermal plasma/cold plasmas are being used in a wide range of new applications in aeronautics, active flow control, heat transfer reduction, plasma-assisted ignition and combustion, noise suppression, and power generation. Industrial applications may be found in pollution control, materials surface treatment, and water purification. In order for these plasma processes to become practical, efficient means of ionization are necessary. A primary challenge for these applications is to create a desired non-equilibrium plasma in air by preventing the discharge from transitioning into an arc. Of particular interest is the impact on simulations and experimental data with and without detailed consideration of non-equilibrium effects, and the consequences of neglecting non-equilibrium. This presentation will provide an assessment of the presence and influence of non-equilibrium phenomena for various aerospace needs and applications. Specific examples to be considered will include the forward energy deposition of laser-induced non-equilibrium plasmoids for sonic boom mitigation, weakly ionized flows obtained from pulsed nanosecond discharges for an annular Hall type MHD generator duct for turbojet energy bypass, and fundamental mechanisms affecting the design and operation of novel plasma-assisted reactive systems in dielectric liquids (water purification, in-pipe modification of fuels, etc.).
Equilibrium sampling by reweighting nonequilibrium simulation trajectories.
Yang, Cheng; Wan, Biao; Xu, Shun; Wang, Yanting; Zhou, Xin
2016-03-01
Based on equilibrium molecular simulations, it is usually difficult to efficiently visit the whole conformational space of complex systems, which are separated into some metastable regions by high free energy barriers. Nonequilibrium simulations could enhance transitions among these metastable regions and then be applied to sample equilibrium distributions in complex systems, since the associated nonequilibrium effects can be removed by employing the Jarzynski equality (JE). Here we present such a systematical method, named reweighted nonequilibrium ensemble dynamics (RNED), to efficiently sample equilibrium conformations. The RNED is a combination of the JE and our previous reweighted ensemble dynamics (RED) method. The original JE reproduces equilibrium from lots of nonequilibrium trajectories but requires that the initial distribution of these trajectories is equilibrium. The RED reweights many equilibrium trajectories from an arbitrary initial distribution to get the equilibrium distribution, whereas the RNED has both advantages of the two methods, reproducing equilibrium from lots of nonequilibrium simulation trajectories with an arbitrary initial conformational distribution. We illustrated the application of the RNED in a toy model and in a Lennard-Jones fluid to detect its liquid-solid phase coexistence. The results indicate that the RNED sufficiently extends the application of both the original JE and the RED in equilibrium sampling of complex systems.
Dynamics of the sputtering of water from ice films by collisions with energetic xenon atoms.
Killelea, Daniel R; Gibson, K D; Yuan, Hanqiu; Becker, James S; Sibener, S J
2012-04-14
The flow of energy from the impact site of a heavy, translationally energetic xenon atom on an ice surface leads to several non-equilibrium events. The central focus of this paper is on the collision-induced desorption (sputtering) of water molecules into the gas-phase from the ice surface. Sputtering is strongly activated with respect to xenon translational energy, and a threshold for desorption was observed. To best understand these results, we discuss our findings in the context of other sputtering studies of molecular solids. The sputtering yield is quite small; differential measurements of the energy of xenon scattered from ice surfaces show that the ice efficiently accommodates the collisional energy. These results are important as they quantitatively elucidate the dynamics of such sputtering events, with implications for energetic non-equilibrium processes at interfaces.
Photoactive energetic materials
Energy Technology Data Exchange (ETDEWEB)
Chavez, David E.; Hanson, Susan Kloek; Scharff, Robert Jason; Veauthier, Jacqueline Marie; Myers, Thomas Winfield
2018-02-27
Energetic materials that are photoactive or believed to be photoactive may include a conventional explosive (e.g. PETN, nitroglycerine) derivatized with an energetic UV-absorbing and/or VIS-absorbing chromophore such as 1,2,4,5-tetrazine or 1,3,5-triazine. Absorption of laser light having a suitably chosen wavelength may result in photodissociation, decomposition, and explosive release of energy. These materials may be used as ligands to form complexes. Coordination compounds include such complexes with counterions. Some having the formula M(L).sub.n.sup.2+ were synthesized, wherein M is a transition metal and L is a ligand and n is 2 or 3. These may be photoactive upon exposure to a laser light beam having an appropriate wavelength of UV light, near-IR and/or visible light. Photoactive materials also include coordination compounds bearing non-energetic ligands; in this case, the counterion may be an oxidant such as perchlorate.
Nonequilibrium molecular dynamics theory, algorithms and applications
Todd, Billy D
2017-01-01
Written by two specialists with over twenty-five years of experience in the field, this valuable text presents a wide range of topics within the growing field of nonequilibrium molecular dynamics (NEMD). It introduces theories which are fundamental to the field - namely, nonequilibrium statistical mechanics and nonequilibrium thermodynamics - and provides state-of-the-art algorithms and advice for designing reliable NEMD code, as well as examining applications for both atomic and molecular fluids. It discusses homogenous and inhomogenous flows and pays considerable attention to highly confined fluids, such as nanofluidics. In addition to statistical mechanics and thermodynamics, the book covers the themes of temperature and thermodynamic fluxes and their computation, the theory and algorithms for homogenous shear and elongational flows, response theory and its applications, heat and mass transport algorithms, applications in molecular rheology, highly confined fluids (nanofluidics), the phenomenon of slip and...
Non-Equilibrium Thermodynamics in Multiphase Flows
Mauri, Roberto
2013-01-01
Non-equilibrium thermodynamics is a general framework that allows the macroscopic description of irreversible processes. This book introduces non-equilibrium thermodynamics and its applications to the rheology of multiphase flows. The subject is relevant to graduate students in chemical and mechanical engineering, physics and material science. This book is divided into two parts. The first part presents the theory of non-equilibrium thermodynamics, reviewing its essential features and showing, when possible, some applications. The second part of this book deals with how the general theory can be applied to model multiphase flows and, in particular, how to determine their constitutive relations. Each chapter contains problems at the end, the solutions of which are given at the end of the book. No prior knowledge of statistical mechanics is required; the necessary prerequisites are elements of transport phenomena and on thermodynamics. “The style of the book is mathematical, but nonetheless it remains very re...
Nonequilibrium thermodynamics of restricted Boltzmann machines
Salazar, Domingos S. P.
2017-08-01
In this work, we analyze the nonequilibrium thermodynamics of a class of neural networks known as restricted Boltzmann machines (RBMs) in the context of unsupervised learning. We show how the network is described as a discrete Markov process and how the detailed balance condition and the Maxwell-Boltzmann equilibrium distribution are sufficient conditions for a complete thermodynamics description, including nonequilibrium fluctuation theorems. Numerical simulations in a fully trained RBM are performed and the heat exchange fluctuation theorem is verified with excellent agreement to the theory. We observe how the contrastive divergence functional, mostly used in unsupervised learning of RBMs, is closely related to nonequilibrium thermodynamic quantities. We also use the framework to interpret the estimation of the partition function of RBMs with the annealed importance sampling method from a thermodynamics standpoint. Finally, we argue that unsupervised learning of RBMs is equivalent to a work protocol in a system driven by the laws of thermodynamics in the absence of labeled data.
Nonequilibrium statistical physics a modern perspective
Livi, Roberto
2017-01-01
Statistical mechanics has been proven to be successful at describing physical systems at thermodynamic equilibrium. Since most natural phenomena occur in nonequilibrium conditions, the present challenge is to find suitable physical approaches for such conditions: this book provides a pedagogical pathway that explores various perspectives. The use of clear language, and explanatory figures and diagrams to describe models, simulations and experimental findings makes the book a valuable resource for undergraduate and graduate students, and also for lecturers organizing teaching at varying levels of experience in the field. Written in three parts, it covers basic and traditional concepts of nonequilibrium physics, modern aspects concerning nonequilibrium phase transitions, and application-orientated topics from a modern perspective. A broad range of topics is covered, including Langevin equations, Levy processes, directed percolation, kinetic roughening and pattern formation.
Non-equilibrium and band tailing in organic conductors
Indian Academy of Sciences (India)
. Non-equilibrium due to coupling between applied energy and free electrons can be responsible for the exponential relaxation from non-equilibrium to equilibrium. Keywords. Band tailing; organic conductors; IR spectra; electrical resistivity.
Thermodynamic model of nonequilibrium phase transitions.
Martyushev, L M; Konovalov, M S
2011-07-01
Within the scope of a thermodynamic description using the maximum entropy production principle, transitions from one nonequilibrium (kinetic) regime to another are considered. It is shown that in the case when power-law dependencies of thermodynamic flux on force are similar for two regimes, only a transition accompanied by a positive jump of thermodynamic flux is possible between them. It is found that the difference in powers of the dependencies of thermodynamic fluxes on forces results in a number of interesting nonequilibrium transitions between kinetic regimes, including the reentrant one with a negative jump of thermodynamic flux.
Canonical operator formulation of nonequilibrium thermodynamics
International Nuclear Information System (INIS)
Mehrafarin, M.
1992-09-01
A novel formulation of nonequilibrium thermodynamics is proposed which emphasises the fundamental role played by the Boltzmann constant k in fluctuations. The equivalence of this and the stochastic formulation is demonstrated. The k → 0 limit of this theory yields the classical deterministic description of nonequilibrium thermodynamics. The new formulation possesses unique features which bear two important results namely the thermodynamic uncertainty principle and the quantisation of entropy production rate. Such a theory becomes indispensable whenever fluctuations play a significant role. (author). 7 refs
Nonideal plasmas as non-equilibrium media
International Nuclear Information System (INIS)
Morozov, I V; Norman, G E; Valuev, A A; Valuev, I A
2003-01-01
Various aspects of the collective behaviour of non-equilibrium nonideal plasmas are studied. The relaxation of kinetic energy to the equilibrium state is simulated by the molecular dynamics (MD) method for two-component non-degenerate strongly non-equilibrium plasmas. The initial non-exponential stage, its duration and the subsequent exponential stage of the relaxation process are studied for a wide range of ion charge, nonideality parameter and ion mass. A simulation model of the nonideal plasma excited by an electron beam is proposed. An approach is developed to calculate the dynamic structure factor in non-stationary conditions. Instability increment is obtained from MD simulations
On the excess energy of nonequilibrium plasma
International Nuclear Information System (INIS)
Timofeev, A. V.
2012-01-01
The energy that can be released in plasma due to the onset of instability (the excess plasma energy) is estimated. Three potentially unstable plasma states are considered, namely, plasma with an anisotropic Maxwellian velocity distribution of plasma particles, plasma with a two-beam velocity distribution, and an inhomogeneous plasma in a magnetic field with a local Maxwellian velocity distribution. The excess energy can serve as a measure of the degree to which plasma is nonequilibrium. In particular, this quantity can be used to compare plasmas in different nonequilibrium states.
Energetics in a model of prebiotic evolution
Intoy, B. F.; Halley, J. W.
2017-12-01
Previously we reported [A. Wynveen et al., Phys. Rev. E 89, 022725 (2014), 10.1103/PhysRevE.89.022725] that requiring that the systems regarded as lifelike be out of chemical equilibrium in a model of abstracted polymers undergoing ligation and scission first introduced by Kauffman [S. A. Kauffman, The Origins of Order (Oxford University Press, New York, 1993), Chap. 7] implied that lifelike systems were most probable when the reaction network was sparse. The model was entirely statistical and took no account of the bond energies or other energetic constraints. Here we report results of an extension of the model to include effects of a finite bonding energy in the model. We studied two conditions: (1) A food set is continuously replenished and the total polymer population is constrained but the system is otherwise isolated and (2) in addition to the constraints in (1) the system is in contact with a finite-temperature heat bath. In each case, detailed balance in the dynamics is guaranteed during the computations by continuous recomputation of a temperature [in case (1)] and of the chemical potential (in both cases) toward which the system is driven by the dynamics. In the isolated case, the probability of reaching a metastable nonequilibrium state in this model depends significantly on the composition of the food set, and the nonequilibrium states satisfying lifelike condition turn out to be at energies and particle numbers consistent with an equilibrium state at high negative temperature. As a function of the sparseness of the reaction network, the lifelike probability is nonmonotonic, as in our previous model, but the maximum probability occurs when the network is less sparse. In the case of contact with a thermal bath at a positive ambient temperature, we identify two types of metastable nonequilibrium states, termed locally and thermally alive, and locally dead and thermally alive, and evaluate their likelihood of appearance, finding maxima at an optimal
Non-equilibrium thermodynamics and physical kinetics
Bikkin, Halid
2014-01-01
This graduate textbook covers contemporary directions of non-equilibrium statistical mechanics as well as classical methods of kinetics. With one of the main propositions being to avoid terms such as "obviously" and "it is easy to show", this treatise is an easy-to-read introduction into this traditional, yet vibrant field.
Non-equilibrium modelling of distillation
Wesselingh, JA; Darton, R
1997-01-01
There are nasty conceptual problems in the classical way of describing distillation columns via equilibrium stages, and efficiencies or HETP's. We can nowadays avoid these problems by simulating the behaviour of a complete column in one go using a non-equilibrium model. Such a model has phase
Evolution and non-equilibrium physics
DEFF Research Database (Denmark)
Becker, Nikolaj; Sibani, Paolo
2014-01-01
We argue that the stochastic dynamics of interacting agents which replicate, mutate and die constitutes a non-equilibrium physical process akin to aging in complex materials. Specifically, our study uses extensive computer simulations of the Tangled Nature Model (TNM) of biological evolution...
Nitroamino and Nitro Energetics
2012-09-13
bis(oxyamine) (Scheme 5), and to investigate energetic ionic liquids based on this bisoxyamine. Nitration of 18 with 100% nitric acid led to the...dihydro-5-nitroimino-l//-tetrazol-l-ly)ethane (43) was obtained.20 The colorless crystals are stable at room temperature and are not hygroscopic ...guanidinium) tetrazine resulted in the formation of dianionic salts 68-72. All of the salts are non hygroscopic , stable in air, and were isolated as
Quantum nonequilibrium equalities with absolute irreversibility
Funo, Ken; Murashita, Yûto; Ueda, Masahito
2015-07-01
We derive quantum nonequilibrium equalities in absolutely irreversible processes. Here by absolute irreversibility we mean that in the backward process the density matrix does not return to the subspace spanned by those eigenvectors that have nonzero weight in the initial density matrix. Since the initial state of a memory and the postmeasurement state of the system are usually restricted to a subspace, absolute irreversibility occurs during the measurement and feedback processes. An additional entropy produced in absolutely irreversible processes needs to be taken into account to derive nonequilibrium equalities. We discuss a model of a feedback control on a qubit system to illustrate the obtained equalities. By introducing N heat baths each composed of a qubit and letting them interact with the system, we show how the entropy reduction via feedback control can be converted into work. An explicit form of extractable work in the presence of absolute irreversibility is given.
Lattice Boltzmann approach for complex nonequilibrium flows.
Montessori, A; Prestininzi, P; La Rocca, M; Succi, S
2015-10-01
We present a lattice Boltzmann realization of Grad's extended hydrodynamic approach to nonequilibrium flows. This is achieved by using higher-order isotropic lattices coupled with a higher-order regularization procedure. The method is assessed for flow across parallel plates and three-dimensional flows in porous media, showing excellent agreement of the mass flow with analytical and numerical solutions of the Boltzmann equation across the full range of Knudsen numbers, from the hydrodynamic regime to ballistic motion.
Low temperature behavior of nonequilibrium multilevel systems
Czech Academy of Sciences Publication Activity Database
Maes, C.; Netočný, Karel; O'Kelly de Galway, W.
2014-01-01
Roč. 47, č. 3 (2014), "035002-1"-"035002-11" ISSN 1751-8113 R&D Projects: GA ČR GAP204/12/0897 Institutional support: RVO:68378271 Keywords : nonequilibrium state state * low temperature Subject RIV: BE - Theoretical Physics Impact factor: 1.583, year: 2014 http://iopscience.iop.org/1751-8121/47/3/035002?fromSearchPage=true
Equilibrium and nonequilibrium behaviour of surfactant systems
Reissig, Louisa
2010-01-01
In binary systems, surfactant molecules can self-assemble into a large variety of structures depending on their chemical structure, concentration and temperature. The properties and stability of the phases, their coexistence regions and the formation of metastable structures is of great importance not only for fundamental understanding, but also for applications in many fields including industry and medicine. This thesis presents studies of the equilibrium and non-equilibrium b...
Improvements to a nonequilibrium algebraic turbulence model
Johnson, D. A.; Coakley, T. J.
1990-01-01
It has been noted that while the nonequilibrium turbulence model of Johnson and King (1985, 1987) performed significantly better than alternative methods, differences between predicted and observed shock locations for certain weak interactions are produced due to a defficiency in the model's inner eddy viscosity formulation. A novel formulation for the model is presented which removes this deficiency, while satisfying the law of the wall for adverse pressure-gradient conditions better than either the original formulation or mixing-length theory.
International Nuclear Information System (INIS)
Abdullayev, K.M.
2005-01-01
The amount of harmful substances (SO 2 ; NO 3 ; CO; CO 2 ) emitted into the atmosphere in 1992-2002 years in the thermal power stations in A zerenerji i s given in this article. As a result of the waste in thermal power stations and electromagnetic emissions in order to reduce the harmful effects of a number of proposals were put forward. It is known that, one of the main polluting areas is energetic. That is why in our opinion the most important issue to look for ways to reduce the harmful effects is the main causes of the environmental impact study
Nonequilibrium functional bosonization of quantum wire networks
Energy Technology Data Exchange (ETDEWEB)
Ngo Dinh, Stephane, E-mail: stephane.ngodinh@kit.edu [Institut fuer Theorie der Kondensierten Materie, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); DFG Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Bagrets, Dmitry A. [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); Mirlin, Alexander D. [Institut fuer Theorie der Kondensierten Materie, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Institut fuer Nanotechnologie, Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); DFG Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Petersburg Nuclear Physics Institute, 188300 St. Petersburg (Russian Federation)
2012-11-15
We develop a general approach to nonequilibrium nanostructures formed by one-dimensional channels coupled by tunnel junctions and/or by impurity scattering. The formalism is based on nonequilibrium version of functional bosonization. A central role in this approach is played by the Keldysh action that has a form reminiscent of the theory of full counting statistics. To proceed with evaluation of physical observables, we assume the weak-tunneling regime and develop a real-time instanton method. A detailed exposition of the formalism is supplemented by two important applications: (i) tunneling into a biased Luttinger liquid with an impurity, and (ii) quantum Hall Fabry-Perot interferometry. - Highlights: Black-Right-Pointing-Pointer A nonequilibrium functional bosonization framework for quantum wire networks is developed Black-Right-Pointing-Pointer For the study of observables in the weak tunneling regime a real-time instanton method is elaborated. Black-Right-Pointing-Pointer We consider tunneling into a biased Luttinger liquid with an impurity. Black-Right-Pointing-Pointer We analyze electronic Fabry-Perot interferometers in the integer quantum Hall regime.
Energetics Manufacturing Technology Center (EMTC)
Federal Laboratory Consortium — The Energetics Manufacturing Technology Center (EMTC), established in 1994 by the Office of Naval Research (ONR) Manufacturing Technology (ManTech) Program, is Navy...
Nonequilibrium Statistical Operator Method and Generalized Kinetic Equations
Kuzemsky, A. L.
2018-01-01
We consider some principal problems of nonequilibrium statistical thermodynamics in the framework of the Zubarev nonequilibrium statistical operator approach. We present a brief comparative analysis of some approaches to describing irreversible processes based on the concept of nonequilibrium Gibbs ensembles and their applicability to describing nonequilibrium processes. We discuss the derivation of generalized kinetic equations for a system in a heat bath. We obtain and analyze a damped Schrödinger-type equation for a dynamical system in a heat bath. We study the dynamical behavior of a particle in a medium taking the dissipation effects into account. We consider the scattering problem for neutrons in a nonequilibrium medium and derive a generalized Van Hove formula. We show that the nonequilibrium statistical operator method is an effective, convenient tool for describing irreversible processes in condensed matter.
On nonequilibrium many-body systems. 1: The nonequilibrium statistical operator method
International Nuclear Information System (INIS)
Algarte, A.C.S.; Vasconcellos, A.R.; Luzzi, R.; Sampaio, A.J.C.
1985-01-01
The theoretical aspects involved in the treatment of many-body systems strongly departed from equilibrium are discussed. The nonequilibrium statistical operator (NSO) method is considered in detail. Using Jaynes' maximum entropy formalism complemented with an ad hoc hypothesis a nonequilibrium statistical operator is obtained. This approach introduces irreversibility from the outset and we recover statistical operators like those of Green-Mori and Zubarev as particular cases. The connection with Generalized Thermodynamics and the construction of nonlinear transport equations are briefly described. (Author) [pt
Nonequilibrium topological phase transitions in two-dimensional optical lattices
Nakagawa, Masaya; Kawakami, Norio
2014-01-01
Recently, concepts of topological phases of matter are extended to nonequilibrium systems, especially periodically driven systems. In this paper, we construct an example which shows nonequilibrium topological phase transitions using ultracold fermions in optical lattices. We show that the Rabi oscillation has the possibility to induce nonequilibrium topological phases which are classified into time-reversal-invariant topological insulators for a two-orbital model of alkaline-earth-metal atoms. Furthermore, we study the nonequilibrium topological phases using time-dependent Schrieffer-Wolff-type perturbation theory, and we obtain an analytical expression to describe the topological phase transitions from a high-frequency limit of external driving fields.
Rural energetic development: cuban experience
International Nuclear Information System (INIS)
Aguilera Barciela, M.
1994-01-01
The development of electro energetic national system in Cuba has been directed to the following objectives: to brake the rural population's exodus toward the cities, electrification of dairy farm, interconnection to the system electro energetic of all the sugar central production, these improves the rural population's conditions life
About Russian nuclear energetic perspectives
International Nuclear Information System (INIS)
Laletin, N.I.
2003-01-01
My particular view about Russian nuclear energetics perspectives is presented. The nearest and the further perspectives are considered. The arguments are adduced that the most probable scenario of nuclear energetic development is its stabilization in the near future. Fur further development the arguments of supporters and opponents of nuclear energetics are analyzed. Three points of view are considered. The first point of view that there is not alternative for nuclear energetics. My notes are the following ones. a) I express a skeptic opinion about a statement of quick exhaustion of fossil organic fuel recourses and corresponding estimations are presented. b) It is expressed skeptic opinion about the statement that nuclear energetics can have a visual influence on ''steam effect''. c) I agree that nuclear energetics is the most ecological technology for normal work but however we can't disregard possibilities of catastrophic accidents. The second point of view that the use of nuclear energetics can't have the justification. I adduce the arguments contrary to this statement. The third point of view that nuclear energetics is a usual technology and the only criteria for discussions about what dimension and where one ought develop it is total cost of its unit. Expressed an opinion that the deceived for the choose of a way the skill of the estimate correctly and optimized so named the external parts of the unit energy costs for different energy technologies. (author)
Fusion zone microstructure of laser beam welded directionally solidified Ni3Al-base alloy IC6
International Nuclear Information System (INIS)
Ding, R.G.; Ojo, O.A.; Chaturvedi, M.C.
2006-01-01
The fusion zone microstructure of laser welded alloy IC6 was examined. Extensive weld-metal cracking was observed to be closely associated with non-equilibrium eutectic-type microconstituents identified as consisting of γ, γ' and NiMo (Y) phases. Their formation has been related to modification of primary solidification path due to reduced solutal microsegregation
Simple models of equilibrium and nonequilibrium phenomena
International Nuclear Information System (INIS)
Lebowitz, J.L.
1987-01-01
This volume consists of two chapters of particular interest to researchers in the field of statistical mechanics. The first chapter is based on the premise that the best way to understand the qualitative properties that characterize many-body (i.e. macroscopic) systems is to study 'a number of the more significant model systems which, at least in principle are susceptible of complete analysis'. The second chapter deals exclusively with nonequilibrium phenomena. It reviews the theory of fluctuations in open systems to which they have made important contributions. Simple but interesting model examples are emphasised
Universality in Nonequilibrium Lattice Systems Theoretical Foundations
Ódor, Géza
2008-01-01
Universal scaling behavior is an attractive feature in statistical physics because a wide range of models can be classified purely in terms of their collective behavior due to a diverging correlation length. This book provides a comprehensive overview of dynamical universality classes occurring in nonequilibrium systems defined on regular lattices. The factors determining these diverse universality classes have yet to be fully understood, but the book attempts to summarize our present knowledge, taking them into account systematically.The book helps the reader to navigate in the zoo of basic m
Nonequilibrium fermion production in quantum field theory
Energy Technology Data Exchange (ETDEWEB)
Pruschke, Jens
2010-06-16
The creation of matter in the early universe or in relativistic heavy-ion collisions is inevitable connected to nonequilibrium physics. One of the key challenges is the explanation of the corresponding thermalization process following nonequilibrium instabilities. The role of fermionic quantum fields in such scenarios is discussed in the literature by using approximations of field theories which neglect important quantum corrections. This thesis goes beyond such approximations. A quantum field theory where scalar bosons interact with Dirac fermions via a Yukawa coupling is analyzed in the 2PI effective action formalism. The chosen approximation allows for a correct description of the dynamics including nonequilibrium instabilities. In particular, fermion-boson loop corrections allow to study the interaction of fermions with large boson fluctuations. The applied initial conditions generate nonequilibrium instabilities like parametric resonance or spinodal instabilities. The equations of motion for correlation functions are solved numerically and major characteristics of the fermion dynamics are described by analytical solutions. New mechanisms for the production of fermions are found. Simulations in the case of spinodal instability show that unstable boson fluctuations induce exponentially growing fermion modes with approximately the same growth rate. If the unstable regime lasts long enough a thermalization of the infrared part of the fermion occupation number occurs on time scales much shorter than the time scale on which bosonic quantum fields thermalize. Fermions acquire an excess of occupation in the ultraviolet regime compared to a Fermi-Dirac statistic characterized by a power-law with exponent two. The fermion production mechanism via parametric resonance is found to be most efficient after the instability ends. Quantum corrections then provide a very efficient particle creation mechanism which is interpreted as an amplification of decay processes. The ratio
Nonequilibrium dynamics in an interacting Fe-C nanoparticle system
DEFF Research Database (Denmark)
Jönsson, P.; Hansen, Mikkel Fougt; Nordblad, P.
2000-01-01
Nonequilibrium dynamics in an interacting Fe-C nanoparticle sample, exhibiting a low-temperature spin-glass-like phase, has been studied by low-frequency ac susceptibility and magnetic relaxation experiments. The nonequilibrium behavior shows characteristic spin-glass features, but some qualitative...
Exploring Chemical and Thermal Non-equilibrium in Nitrogen Arcs
International Nuclear Information System (INIS)
Ghorui, S; Das, A K
2012-01-01
Plasma torches operating with nitrogen are of special importance as they can operate with usual tungsten based refractory electrodes and offer radical rich non-oxidizing high temperature environment for plasma chemistry. Strong gradients in temperature as well as species densities and huge convective fluxes lead to varying degrees of chemical non-equilibrium in associated regions. An axi-symmetric two-temperature chemical non-equilibrium model of a nitrogen plasma torch has been developed to understand the effects of thermal and chemical non-equilibrium in arcs. A 2-D finite volume CFD code in association with a non-equilibrium property routine enabled extraction of steady state self-consistent distributions of various plasma quantities inside the torch under various thermal and chemical non-equilibrium conditions. Chemical non-equilibrium has been incorporated through computation of diffusive and convective fluxes in each finite volume cell in every iteration and associating corresponding thermodynamic and transport properties through the scheme of 'chemical non-equilibrium parameter' introduced by Ghorui et. al. Recombination coefficient data from Nahar et. al. and radiation data from Krey and Morris have been used in the simulation. Results are presented for distributions of temperature, pressure, velocity, current density, electric potential, species densities and chemical non-equilibrium effects. Obtained results are compared with similar results under LTE.
Nonequilibrium dynamical mean-field theory
International Nuclear Information System (INIS)
Eckstein, Martin
2009-01-01
The aim of this thesis is the investigation of strongly interacting quantum many-particle systems in nonequilibrium by means of the dynamical mean-field theory (DMFT). An efficient numerical implementation of the nonequilibrium DMFT equations within the Keldysh formalism is provided, as well a discussion of several approaches to solve effective single-site problem to which lattice models such as the Hubbard-model are mapped within DMFT. DMFT is then used to study the relaxation of the thermodynamic state after a sudden increase of the interaction parameter in two different models: the Hubbard model and the Falicov-Kimball model. In the latter case an exact solution can be given, which shows that the state does not even thermalize after infinite waiting times. For a slow change of the interaction, a transition to adiabatic behavior is found. The Hubbard model, on the other hand, shows a very sensitive dependence of the relaxation on the interaction, which may be called a dynamical phase transition. Rapid thermalization only occurs at the interaction parameter which corresponds to this transition. (orig.)
Nonequilibrium dynamical mean-field theory
Energy Technology Data Exchange (ETDEWEB)
Eckstein, Martin
2009-12-21
The aim of this thesis is the investigation of strongly interacting quantum many-particle systems in nonequilibrium by means of the dynamical mean-field theory (DMFT). An efficient numerical implementation of the nonequilibrium DMFT equations within the Keldysh formalism is provided, as well a discussion of several approaches to solve effective single-site problem to which lattice models such as the Hubbard-model are mapped within DMFT. DMFT is then used to study the relaxation of the thermodynamic state after a sudden increase of the interaction parameter in two different models: the Hubbard model and the Falicov-Kimball model. In the latter case an exact solution can be given, which shows that the state does not even thermalize after infinite waiting times. For a slow change of the interaction, a transition to adiabatic behavior is found. The Hubbard model, on the other hand, shows a very sensitive dependence of the relaxation on the interaction, which may be called a dynamical phase transition. Rapid thermalization only occurs at the interaction parameter which corresponds to this transition. (orig.)
Nonequilibrium free diffusion in seed leachate
Ortiz G., Luis; Riquelme P., Pablo; Guzmán, R.
2013-11-01
In this work, we use a Schlieren-like Near Field Scattering (SNFS) setup to study nonequilibrium free diffusion behavior of a colloidal solution obtained from seeds leachate. The main objective is to compare the temporal behavior of the diffusion coefficient of seed leachate with an electric conductivity based vigor test. SNFS sizing measurements, based on Mie theory, were carried out to ensure its reliability and sensitivity. Then, we performed a typical nonequilibrium free diffusion experiment of a glycerol-water mixture. In this way, we confirmed that SNFS setup is sensitive to giant concentration fluctuations of nanocolloidal solutions. The results obtained in this stage reproduce properly the data reported elsewhere in literature. Moreover, seed leachate diffuse, in water, in a similar way that glycerol does. In both cases we used the same method (dynamic structure factor) to determine thermo-physical properties. We show that time evolution of diffusion coefficient of Lupinus Albus leachate exhibits three defined regimes as electric conductivity measurements. The results also exhibit a correspondence between the behavior of the diffusion coefficient and electric conductivity values of the two regions in the temporal range studied. Finally, we discuss biological processes involved in germination that could modulate this dependence, and the role played by the electrolytic nature of solutes.
Non-equilibrium many body dynamics
Energy Technology Data Exchange (ETDEWEB)
Creutz, M.; Gyulassy, M.
1997-09-22
This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop.
Non-equilibrium many body dynamics
International Nuclear Information System (INIS)
Creutz, M.; Gyulassy, M.
1997-01-01
This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop
Analysis of the energetic sector through the national energetic matrix
International Nuclear Information System (INIS)
Garzon Lozano, Enrique
2007-01-01
The author shows the results of the national energetic balance 1975-2005, through the energetic matrix of the country, giving an annual growth of 5.1% in this period of offer of primary energy, where the mineral coal participates with 9,6%, the hydraulic energy with 4,8%, natural gas with 4,2%, trash with 2,4% and petroleum with 2,2%, while the firewood fell in 0,5%
International Nuclear Information System (INIS)
2008-01-01
This power point exhibition shows the following topics: energy analysis, production and use, supply and demand, consumption, energy sources, energetic prospective of Uruguay country, medium and long term perspectives.
Photodecomposition of energetic nitro compounds
Energy Technology Data Exchange (ETDEWEB)
Mialocq, J.C.
1989-03-14
The photodecomposition of energetic nitrocompounds depends on the excitation energy, the light intensity which determines the mono-, bi- or multiphotonic character of the initial process and their gaseous, liquid or solid state. The initial processes of the photodecomposition of nitromethane and nitroalcanes are reviewed and their relevance to the initiation of energetic nitrocompounds detonation is discussed. The case of nitramines (dimethylnitramine and tutorial) is also briefly introduced.
Non-equilibrium synergistic effects in atmospheric pressure plasmas.
Guo, Heng; Zhang, Xiao-Ning; Chen, Jian; Li, He-Ping; Ostrikov, Kostya Ken
2018-03-19
Non-equilibrium is one of the important features of an atmospheric gas discharge plasma. It involves complicated physical-chemical processes and plays a key role in various actual plasma processing. In this report, a novel complete non-equilibrium model is developed to reveal the non-equilibrium synergistic effects for the atmospheric-pressure low-temperature plasmas (AP-LTPs). It combines a thermal-chemical non-equilibrium fluid model for the quasi-neutral plasma region and a simplified sheath model for the electrode sheath region. The free-burning argon arc is selected as a model system because both the electrical-thermal-chemical equilibrium and non-equilibrium regions are involved simultaneously in this arc plasma system. The modeling results indicate for the first time that it is the strong and synergistic interactions among the mass, momentum and energy transfer processes that determine the self-consistent non-equilibrium characteristics of the AP-LTPs. An energy transfer process related to the non-uniform spatial distributions of the electron-to-heavy-particle temperature ratio has also been discovered for the first time. It has a significant influence for self-consistently predicting the transition region between the "hot" and "cold" equilibrium regions of an AP-LTP system. The modeling results would provide an instructive guidance for predicting and possibly controlling the non-equilibrium particle-energy transportation process in various AP-LTPs in future.
Nonomura, Yoshihiko; Tomita, Yusuke
2015-03-01
Recently we have found that the nonequilibrium relaxation from the perfectly-ordered state of the 2D and 3D Ising models in cluster algorithms shows nontrivial stretched-exponential decay at the transition temperature. Similar nontrivial nonequilibrium critical relaxation is also observed in the 2D XY, 3D XY and 3D Heisenberg models; simple exponential decay in these cases. In order to confirm these behaviors and evaluate the scaling form precisely and robustly, we have proposed a universal scaling procedure to connect nonequilibrium and equilibrium behaviors continuously. For example, when the critical relaxation of the average magnetization of a system with linear size L is observed in local-update algorithms, this quantity decays in a power law in the early-stage relaxation with ~t - β / (zν) and converges to the critical magnetization mc (L) ~L - β / ν in equilibrium. Then, when L β / ν is plotted versus tL-z , data for various system sizes are scaled on a single curve in the whole parameter region. This procedure also holds for the cases with cluster algorithms.
Thermodynamics of Nonequilibrium Systems with Feedback Control
Sagawa, Takahiro
2015-03-01
In modern nonequilibrium physics, ``Maxwell's demon'' has attracted renewed attentions in both terms of theory and experiment. The demon plays a key role to unify thermodynamics and information theory, which can extract the useful work from a heat bath by using the obtained information via feedback control. In this talk, I will talk about the recent development of thermodynamics of information. In particular, I will focus on the generalizations of the second law of thermodynamics and the Jarzynski equality in the presence of feedback control, where information contents and thermodynamic quantities are treated on an equal footing. I will also discuss recent experimental results that realized Maxwell's demon by colloidal particles and single electrons.
Non-equilibrium in flowing atmospheric plasmas
International Nuclear Information System (INIS)
Haas, J.C.M. de.
1986-01-01
This thesis deals with the fundamental aspects of two different plasmas applied in technological processes. The first one is the cesium seeded argon plasma in a closed cycle Magnetohydrodynamic (MHD) generator, the second is the thermal argon plasma in a cascade arc with an imposed flow. In Chapter 2 the influence of non-equilibrium on the mass and energy balances of a plasma is worked out. The general theory presented there can be applied to both the plasma in an MHD generator and to the cascade arc with imposed flow. Introductions to these plasmas are given in the Chapters 3 and 6 respectively. These chapters are both followed by two chapters which treat the theoretical and the experimental investigations. The results are summarized in Chapter 9. (Auth.)
Non-equilibrium effects in the plasmas
International Nuclear Information System (INIS)
Einfeld, D.
1975-01-01
Radial dependences of non-equilibrium effects of a He plasma were studied in a wall-stabilized short-time discharge. The electron density (nsub(e) = 2.5 x 10 22 m -3 ), the electron temperature and the equilibrium shift were determined by calculations of the continuum beam density and the beam densities of one He-I and one He-II line, respectively. In the discharge axis, the overpopulation factors of the ground state of He-I and He-II are about 75. As the distance to the axis increases, they increase for He-I and decrease for He-II. Except for the usual errors of measurement, the overpopulation factors found here correspond to those calculated from the balance equations (Drawin). (orig./AK) [de
Nonequilibrium work relation in a macroscopic system
International Nuclear Information System (INIS)
Sughiyama, Yuki; Ohzeki, Masayuki
2013-01-01
We reconsider a well-known relationship between the fluctuation theorem and the second law of thermodynamics by evaluating stochastic evolution of the density field (probability measure valued process). In order to establish a bridge between microscopic and macroscopic behaviors, we must take the thermodynamic limit of a stochastic dynamical system following the standard procedure in statistical mechanics. The thermodynamic path characterizing a dynamical behavior in the macroscopic scale can be formulated as an infimum of the action functional for the stochastic evolution of the density field. In our formulation, the second law of thermodynamics can be derived only by symmetry of the action functional without recourse to the Jarzynski equality. Our formulation leads to a nontrivial nonequilibrium work relation for metastable (quasi-stationary) states, which are peculiar in the macroscopic system. We propose a prescription for computing the free energy for metastable states based on the resultant work relation. (paper)
Magnetic polarons in a nonequilibrium polariton condensate
Mietki, Paweł; Matuszewski, Michał
2017-09-01
We consider a condensate of exciton polaritons in a diluted magnetic semiconductor microcavity. Such a system may exhibit magnetic self-trapping in the case of sufficiently strong coupling between polaritons and magnetic ions embedded in the semiconductor. We investigate the effect of the nonequilibrium nature of exciton polaritons on the physics of the resulting self-trapped magnetic polarons. We find that multiple polarons can exist at the same time, and we derive a critical condition for self-trapping that is different from the one predicted previously in the equilibrium case. Using the Bogoliubov-de Gennes approximation, we calculate the excitation spectrum and provide a physical explanation in terms of the effective magnetic attraction between polaritons, mediated by the ion subsystem.
Shortcuts to isothermality and nonequilibrium work relations.
Li, Geng; Quan, H T; Tu, Z C
2017-07-01
In conventional thermodynamics, it is widely acknowledged that the realization of an isothermal process for a system requires a quasistatic controlling protocol. Here we propose and design a strategy to realize a finite-rate isothermal transition from an equilibrium state to another one at the same temperature, which is named the "shortcut to isothermality." By using shortcuts to isothermality, we derive three nonequilibrium work relations, including an identity between the free-energy difference and the mean work due to the potential of the original system, a Jarzynski-like equality, and the inverse relationship between the dissipated work and the total driving time. We numerically test these three relations by considering the motion of a Brownian particle trapped in a harmonic potential and dragged by a time-dependent force.
Nanoscale hotspots due to nonequilibrium thermal transport
International Nuclear Information System (INIS)
Sinha, Sanjiv; Goodson, Kenneth E.
2004-01-01
Recent experimental and modeling efforts have been directed towards the issue of temperature localization and hotspot formation in the vicinity of nanoscale heat generating devices. The nonequilibrium transport conditions which develop around these nanoscale devices results in elevated temperatures near the heat source which can not be predicted by continuum diffusion theory. Efforts to determine the severity of this temperature localization phenomena in silicon devices near and above room temperature are of technological importance to the development of microelectronics and other nanotechnologies. In this work, we have developed a new modeling tool in order to explore the magnitude of the additional thermal resistance which forms around nanoscale hotspots from temperatures of 100-1000K. The models are based on a two fluid approximation in which thermal energy is transferred between ''stationary'' optical phonons and fast propagating acoustic phonon modes. The results of the model have shown excellent agreement with experimental results of localized hotspots in silicon at lower temperatures. The model predicts that the effect of added thermal resistance due to the nonequilibrium phonon distribution is greatest at lower temperatures, but is maintained out to temperatures of 1000K. The resistance predicted by the numerical code can be easily integrated with continuum models in order to predict the temperature distribution around nanoscale heat sources with improved accuracy. Additional research efforts also focused on the measurements of the thermal resistance of silicon thin films at higher temperatures, with a focus on polycrystalline silicon. This work was intended to provide much needed experimental data on the thermal transport properties for micro and nanoscale devices built with this material. Initial experiments have shown that the exposure of polycrystalline silicon to high temperatures may induce recrystallization and radically increase the thermal
Musical Tasks and Energetic Arousal.
Lim, Hayoung A; Watson, Angela L
2018-03-08
Music is widely recognized as a motivating stimulus. Investigators have examined the use of music to improve a variety of motivation-related outcomes; however, these studies have focused primarily on passive music listening rather than active participation in musical activities. To examine the influence of participation in musical tasks and unique participant characteristics on energetic arousal. We used a one-way Welch's ANOVA to examine the influence of musical participation (i.e., a non-musical control and four different musical task conditions) upon energetic arousal. In addition, ancillary analyses of participant characteristics including personality, age, gender, sleep, musical training, caffeine, nicotine, and alcohol revealed their possible influence upon pretest and posttest energetic arousal scores. Musical participation yielded a significant relationship with energetic arousal, F(4, 55.62) = 44.38, p = .000, estimated ω2 = 0.60. Games-Howell post hoc pairwise comparisons revealed statistically significant differences between five conditions. Descriptive statistics revealed expected differences between introverts' and extraverts' energetic arousal scores at the pretest, F(1, 115) = 6.80, p = .010, partial η2= .06; however, mean differences failed to reach significance at the posttest following musical task participation. No other measured participant characteristics yielded meaningful results. Passive tasks (i.e., listening to a story or song) were related to decreased energetic arousal, while active musical tasks (i.e., singing, rhythm tapping, and keyboard playing) were related to increased energetic arousal. Musical task participation appeared to have a differential effect for individuals with certain personality traits (i.e., extroverts and introverts).
Atomistic Simulation of Non-Equilibrium Phenomena in Hypersonic Flows
Norman, Paul Erik
The goal of this work is to model the heterogeneous recombination of atomic oxygen on silica surfaces, which is of interest for accurately predicting the heating on vehicles traveling at hypersonic speeds. This is accomplished by creating a finite rate catalytic model, which describes recombination with a set of elementary gas-surface reactions. Fundamental to a description of surface catalytic reactions are the in situ chemical structures on the surface where recombination can occur. Using molecular dynamics simulations with the Reax GSISiO potential, we find that the chemical sites active in direct gas-phase reactions on silica surfaces consist of a small number of specific structures (or defects). The existence of these defects on real silica surfaces is supported by experimental results and the structure and energetics of these defects have been verified with quantum chemical calculations. The reactions in the finite rate catalytic model are based on the interaction of molecular and atomic oxygen with these defects. Trajectory calculations are used to find the parameters in the forward rate equations, while a combination of detailed balance and transition state theory are used to find the parameters in the reverse rate equations. The rate model predicts that the oxygen recombination coefficient is relatively constant at T (300-1000 K), in agreement with experimental results. At T > 1000 K the rate model predicts a drop off in the oxygen recombination coefficient, in disagreement with experimental results, which predict that the oxygen recombination coefficient increases with temperature. A discussion of the possible reasons for this disagreement, including non-adiabatic collision dynamics, variable surface site concentrations, and additional recombination mechanisms is presented. This thesis also describes atomistic simulations with Classical Trajectory Calculation Direction Simulation Monte Carlo (CTC-DSMC), a particle based method for modeling non-equilibrium
Nonequilibrium electron transport through quantum dots in the Kondo regime
DEFF Research Database (Denmark)
Wölfle, Peter; Paaske, Jens; Rosch, Achim
2005-01-01
Electron transport at large bias voltage through quantum dots in the Kondo regime is described within the perturbative renormalization group extended to nonequilibrium. The conductance, local magnetization, dynamical spin susceptibility and local spectral function are calculated. We show how the ...
Non-Equilibrium Thermodynamics of Self-Replicating Protocells
DEFF Research Database (Denmark)
Fellermann, Harold; Corominas-Murtra, Bernat; Hansen, Per Lyngs
2018-01-01
We provide a non-equilibrium thermodynamic description of the life-cycle of a droplet based, chemically feasible, system of protocells. By coupling the protocells metabolic kinetics with its thermodynamics, we demonstrate how the system can be driven out of equilibrium to ensure protocell growth...... and replication. This coupling allows us to derive the equations of evolution and to rigorously demonstrate how growth and replication life-cycle can be understood as a non-equilibrium thermodynamic cycle. The process does not appeal to genetic information or inheritance, and is based only on non......-equilibrium physics considerations. Our non-equilibrium thermodynamic description of simple, yet realistic, processes of protocell growth and replication, represents an advance in our physical understanding of a central biological phenomenon both in connection to the origin of life and for modern biology....
Nonequilibrium structure of colloidal dumbbells under oscillatory shear.
Heptner, Nils; Chu, Fangfang; Lu, Yan; Lindner, Peter; Ballauff, Matthias; Dzubiella, Joachim
2015-11-01
We investigate the nonequilibrium behavior of dense, plastic-crystalline suspensions of mildly anisotropic colloidal hard dumbbells under the action of an oscillatory shear field by employing Brownian dynamics computer simulations. In particular, we extend previous investigations, where we uncovered nonequilibrium phase transitions, to other aspect ratios and to a larger nonequilibrium parameter space, that is, a wider range of strains and shear frequencies. We compare and discuss selected results in the context of scattering and rheological experiments. Both simulations and experiments demonstrate that the previously found transitions from the plastic crystal phase with increasing shear strain also occur at other aspect ratios. We explore the transition behavior in the strain-frequency phase and summarize it in a nonequilibrium phase diagram. Additionally, the experimental rheology results hint at a slowing down of the colloidal dynamics with higher aspect ratio.
Electrolytes: transport properties and non-equilibrium thermodynamics
International Nuclear Information System (INIS)
Miller, D.G.
1980-12-01
This paper presents a review on the application of non-equilibrium thermodynamics to transport in electrolyte solutions, and some recent experimental work and results for mutual diffusion in electrolyte solutions
Nonequilibrium phonon effects in midinfrared quantum cascade lasers
Energy Technology Data Exchange (ETDEWEB)
Shi, Y. B., E-mail: yshi9@wisc.edu; Knezevic, I., E-mail: knezevic@engr.wisc.edu [Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706-1691 (United States)
2014-09-28
We investigate the effects of nonequilibrium phonon dynamics on the operation of a GaAs-based midinfrared quantum cascade laser over a range of temperatures (77–300 K) via a coupled ensemble Monte Carlo simulation of electron and optical-phonon systems. Nonequilibrium phonon effects are shown to be important below 200 K. At low temperatures, nonequilibrium phonons enhance injection selectivity and efficiency by drastically increasing the rate of interstage electron scattering from the lowest injector state to the next-stage upper lasing level via optical-phonon absorption. As a result, the current density and modal gain at a given field are higher and the threshold current density lower and considerably closer to experiment than results obtained with thermal phonons. By amplifying phonon absorption, nonequilibrium phonons also hinder electron energy relaxation and lead to elevated electronic temperatures.
Second School of Nuclear Energetics
International Nuclear Information System (INIS)
2009-01-01
At 3-5 Nov 2009 Institute of Nuclear Energy POLATOM, Association of Polish Electrical Engineers (SEP) and Polish Nuclear Society have organized Second School of Nuclear Energetics. 165 participants have arrived from all Poland and represented both different central institutions (e.g. ministries) and local institutions (e.g. Office of Technical Inspection, The Voivodship Presidential Offices, several societies, consulting firms or energetic enterprises). Students from the Warsaw Technical University and Gdansk Technical University, as well as the PhD students from the Institute of Nuclear Chemistry and Technology (Warsaw) attended the School. 20 invited lectures presented by eminent Polish specialists concerned basic problems of nuclear energetics, nuclear fuel cycle and different problems of the NPP construction in Poland. [pl
Nonequilibrium flow calculations for the hydrogen constricted arc
Scott, R. K.; Incropera, F. P.
1973-01-01
A nonequilibrium flow model has been formulated and solved numerically for conditions in an atomic hydrogen cascade arc. Solutions show that although thermal nonequilibrium effects are minor, the departure from chemical equilibrium is significant. Comparisons with results obtained from an equilibrium flow model reveal the deficiencies associated with such a model and parametric calculations reveal the effect of current, pressure, and radius on arc behavior.
Non-equilibrium dynamics from RPMD and CMD.
Welsch, Ralph; Song, Kai; Shi, Qiang; Althorpe, Stuart C; Miller, Thomas F
2016-11-28
We investigate the calculation of approximate non-equilibrium quantum time correlation functions (TCFs) using two popular path-integral-based molecular dynamics methods, ring-polymer molecular dynamics (RPMD) and centroid molecular dynamics (CMD). It is shown that for the cases of a sudden vertical excitation and an initial momentum impulse, both RPMD and CMD yield non-equilibrium TCFs for linear operators that are exact for high temperatures, in the t = 0 limit, and for harmonic potentials; the subset of these conditions that are preserved for non-equilibrium TCFs of non-linear operators is also discussed. Furthermore, it is shown that for these non-equilibrium initial conditions, both methods retain the connection to Matsubara dynamics that has previously been established for equilibrium initial conditions. Comparison of non-equilibrium TCFs from RPMD and CMD to Matsubara dynamics at short times reveals the orders in time to which the methods agree. Specifically, for the position-autocorrelation function associated with sudden vertical excitation, RPMD and CMD agree with Matsubara dynamics up to O(t 4 ) and O(t 1 ), respectively; for the position-autocorrelation function associated with an initial momentum impulse, RPMD and CMD agree with Matsubara dynamics up to O(t 5 ) and O(t 2 ), respectively. Numerical tests using model potentials for a wide range of non-equilibrium initial conditions show that RPMD and CMD yield non-equilibrium TCFs with an accuracy that is comparable to that for equilibrium TCFs. RPMD is also used to investigate excited-state proton transfer in a system-bath model, and it is compared to numerically exact calculations performed using a recently developed version of the Liouville space hierarchical equation of motion approach; again, similar accuracy is observed for non-equilibrium and equilibrium initial conditions.
Nanostructured energetic materials derived from sol-gel chemistry
International Nuclear Information System (INIS)
Simpson, R L; Tillotson, T M; Hrubesh, L W; Gash, A E
2000-01-01
Initiation and detonation properties are dramatically affected by an energetic material's microstructural properties. Sol-gel chemistry allows intimacy of mixing to be controlled and dramatically improved over existing methodologies. One material goal is to create very high power energetic materials which also have high energy densities. Using sol-gel chemistry we have made a nanostructured composite energetic material. Here a solid skeleton of fuel, based on resorcinol-formaldehyde, has nanocrystalline ammonium perchlorate, the oxidizer, trapped within its pores. At optimum stoichiometry it has approximately the energy density of HMX. Transmission electron microscopy indicated no ammonium perchlorate crystallites larger than 20 nm while near-edge soft x-ray absorption microscopy showed that nitrogen was uniformly distributed, at least on the scale of less than 80 nm. Small-angle neutron scattering studies were conducted on the material. Those results were consistent with historical ones for this class of nanostructured materials. The average skeletal primary particle size was on the order of 2.7 nm, while the nanocomposite showed the growth of small 1 nm size crystals of ammonium perchlorate with some clustering to form particles greater than 10 nm
Nanostructured energetic materials derived from sol-gel chemistry
Energy Technology Data Exchange (ETDEWEB)
Simpson, R L; Tillotson, T M; Hrubesh, L W; Gash, A E
2000-03-15
Initiation and detonation properties are dramatically affected by an energetic material's microstructural properties. Sol-gel chemistry allows intimacy of mixing to be controlled and dramatically improved over existing methodologies. One material goal is to create very high power energetic materials which also have high energy densities. Using sol-gel chemistry we have made a nanostructured composite energetic material. Here a solid skeleton of fuel, based on resorcinol-formaldehyde, has nanocrystalline ammonium perchlorate, the oxidizer, trapped within its pores. At optimum stoichiometry it has approximately the energy density of HMX. Transmission electron microscopy indicated no ammonium perchlorate crystallites larger than 20 nm while near-edge soft x-ray absorption microscopy showed that nitrogen was uniformly distributed, at least on the scale of less than 80 nm. Small-angle neutron scattering studies were conducted on the material. Those results were consistent with historical ones for this class of nanostructured materials. The average skeletal primary particle size was on the order of 2.7 nm, while the nanocomposite showed the growth of small 1 nm size crystals of ammonium perchlorate with some clustering to form particles greater than 10 nm.
Achieving Radiation Tolerance through Non-Equilibrium Grain Boundary Structures.
Vetterick, Gregory A; Gruber, Jacob; Suri, Pranav K; Baldwin, Jon K; Kirk, Marquis A; Baldo, Pete; Wang, Yong Q; Misra, Amit; Tucker, Garritt J; Taheri, Mitra L
2017-09-25
Many methods used to produce nanocrystalline (NC) materials leave behind non-equilibrium grain boundaries (GBs) containing excess free volume and higher energy than their equilibrium counterparts with identical 5 degrees of freedom. Since non-equilibrium GBs have increased amounts of both strain and free volume, these boundaries may act as more efficient sinks for the excess interstitials and vacancies produced in a material under irradiation as compared to equilibrium GBs. The relative sink strengths of equilibrium and non-equilibrium GBs were explored by comparing the behavior of annealed (equilibrium) and as-deposited (non-equilibrium) NC iron films on irradiation. These results were coupled with atomistic simulations to better reveal the underlying processes occurring on timescales too short to capture using in situ TEM. After irradiation, NC iron with non-equilibrium GBs contains both a smaller number density of defect clusters and a smaller average defect cluster size. Simulations showed that excess free volume contribute to a decreased survival rate of point defects in cascades occurring adjacent to the GB and that these boundaries undergo less dramatic changes in structure upon irradiation. These results suggest that non-equilibrium GBs act as more efficient sinks for defects and could be utilized to create more radiation tolerant materials in future.
Nonequilibrium emergent phenomena in organic molecular solids
Energy Technology Data Exchange (ETDEWEB)
Mitrano, Matteo
2015-07-15
The manipulation of matter with ultrashort laser pulses is a relevant research field from both a fundamental and an applied perspective, owing to the efficient coupling to the electronic degrees of freedom on femtosecond timescales and the ability to induce transient phases that cannot be realized in equilibrium scenarios. Strongly correlated materials are a natural environment for the observation of such novel and emergent out-of-equilibrium physics because small modifications to the electron-electron interactions can induce transitions between remarkably different macroscopic phases. One of the most effective means of modifying the effective electron-electron interactions is to perturb the crystal structure through pressure, strain or even light. However, it remains largely unexplored how perturbing the structural degrees of freedom affects the electron dynamics of the transiently driven states and how the interplay of correlations and electron-lattice interactions determine the intrinsic timescales of these nonequilibrium states. This thesis investigates how to control the light-induced nonequilibrium electronic properties in strongly correlated organics, that are highly tunable with moderate variations of external parameters, by perturbing their structural degrees of freedom, either via static pressures or vibrational excitation. We study the role of correlations in determining the relaxation rate of holes (holons) and double occupancies (doublons) in a solid state Mott insulator, the ET-F{sub 2}TCNQ, driven across a transient insulator-to-metal transition. By mapping holon-doublon lifetimes onto the ground-state electronic interactions, we found that the decay rate of the photoinjected quasiparticles depends on the degree of correlation between carriers and is affected by the presence of a competition between local recombination and delocalization of holon-doublon pairs. By optically controlling the effective correlations in organic molecular crystals through
Complex Dynamics in Nonequilibrium Economics and Chemistry
Wen, Kehong
Complex dynamics provides a new approach in dealing with economic complexity. We study interactively the empirical and theoretical aspects of business cycles. The way of exploring complexity is similar to that in the study of an oscillatory chemical system (BZ system)--a model for modeling complex behavior. We contribute in simulating qualitatively the complex periodic patterns observed from the controlled BZ experiments to narrow the gap between modeling and experiment. The gap between theory and reality is much wider in economics, which involves studies of human expectations and decisions, the essential difference from natural sciences. Our empirical and theoretical studies make substantial progress in closing this gap. With the help from the new development in nonequilibrium physics, i.e., the complex spectral theory, we advance our technique in detecting characteristic time scales from empirical economic data. We obtain correlation resonances, which give oscillating modes with decays for correlation decomposition, from different time series including S&P 500, M2, crude oil spot prices, and GNP. The time scales found are strikingly compatible with business experiences and other studies in business cycles. They reveal the non-Markovian nature of coherent markets. The resonances enhance the evidence of economic chaos obtained by using other tests. The evolving multi-humped distributions produced by the moving-time -window technique reveal the nonequilibrium nature of economic behavior. They reproduce the American economic history of booms and busts. The studies seem to provide a way out of the debate on chaos versus noise and unify the cyclical and stochastic approaches in explaining business fluctuations. Based on these findings and new expectation formulation, we construct a business cycle model which gives qualitatively compatible patterns to those found empirically. The soft-bouncing oscillator model provides a better alternative than the harmonic oscillator
On energetics of hydrocarbon chemical reactions by ionizing irradiation
International Nuclear Information System (INIS)
Zaykin, Yu.A.; Zaykina, R.F.; Mirkin, G.
2002-01-01
Complete text of publication follows. The present global energy crisis requires the industry to look for technologies that are more effective and, particularly, less energy consuming. The hydrocarbon processing technology based on the electron radiation-induced thermal chemical conversion has a great potential. Comparing the presently predominant thermocatalytic processing, it is much more energy efficient, because chemical conversions go at a minimal processing temperature and pressure. To compare energy consumption by electron irradiation with thermal and thermocatalytic technologies of hydrocarbon processing one must see major differences between them. While traditional thermocatalytic processes are equilibrium and their energetics can be evaluated based on principles of classic thermodynamics, HEET processing is non-equilibrium and this evaluation approach is not valid for it. However, a theoretical description of radiation-chemical conversion using reaction rate constants determined in thermally equilibrium systems is approximately adequate to radiation processes by substituting equilibrium concentrations of reacting particles as their non-equilibrium concentrations under irradiation. In particular, description of radical reactions initiated by radiation requires substitution of thermally equilibrium radical concentration by much higher concentration defined by the dynamic equilibrium of radical radiation generation and their recombination. The paper presents the comparative analysis of energy consumption in different stages of hydrocarbon processing using classic thermal cracking by heating versus radiation induced cracking. It is shown that in the most energy-consuming stage of processing - the chain reaction initiation necessary for concentration of active radicals, irradiation processing has the great advantage compared to thermal cracking by heating and allows cutting down the total energy consumption by approximately 40%
Nonequilibrium landscape theory of neural networks
Yan, Han; Zhao, Lei; Hu, Liang; Wang, Xidi; Wang, Erkang; Wang, Jin
2013-01-01
The brain map project aims to map out the neuron connections of the human brain. Even with all of the wirings mapped out, the global and physical understandings of the function and behavior are still challenging. Hopfield quantified the learning and memory process of symmetrically connected neural networks globally through equilibrium energy. The energy basins of attractions represent memories, and the memory retrieval dynamics is determined by the energy gradient. However, the realistic neural networks are asymmetrically connected, and oscillations cannot emerge from symmetric neural networks. Here, we developed a nonequilibrium landscape–flux theory for realistic asymmetrically connected neural networks. We uncovered the underlying potential landscape and the associated Lyapunov function for quantifying the global stability and function. We found the dynamics and oscillations in human brains responsible for cognitive processes and physiological rhythm regulations are determined not only by the landscape gradient but also by the flux. We found that the flux is closely related to the degrees of the asymmetric connections in neural networks and is the origin of the neural oscillations. The neural oscillation landscape shows a closed-ring attractor topology. The landscape gradient attracts the network down to the ring. The flux is responsible for coherent oscillations on the ring. We suggest the flux may provide the driving force for associations among memories. We applied our theory to rapid-eye movement sleep cycle. We identified the key regulation factors for function through global sensitivity analysis of landscape topography against wirings, which are in good agreements with experiments. PMID:24145451
Nonequilibrium in a low power arcjet nozzle
Zube, Dieter M.; Myers, Roger M.
1991-01-01
Emission spectroscopy measurements were made of the plasma flow inside the nozzle of a 1 kW class arcjet thruster. The thruster propellant was a hydrogen-nitrogen mixture used to simulate fully decomposed hydrazine. The 0.25 mm diameter holes were drilled into the diverging section of the tungsten thruster nozzle to provide optical access to the internal flow. Atomic electron excitation, vibrational, and rotational temperatures were determined for the expanding plasma using relative line intensity techniques. The atomic excitation temperatures decreased from 18,000K at a location 3 mm downstream of the constrictor to 9,000K at a location 9 mm from the constrictor, while the molecular vibrational and rotational temperatures decreased from 6,500K to 2,500K and from 8,000K to 3,000K, respectively, between the same locations. The electron density measured using hydrogen H line Stark broadening decreased from about 10(exp 15) cm(-3) to about 2 times 10(exp 14) cm(-3) during the expansion. The results show that the plasma is highly nonequilibrium throughout the nozzle, with most relaxation times equal or exceeding the particle residence time.
Gibbsian Stationary Non-equilibrium States
De Carlo, Leonardo; Gabrielli, Davide
2017-09-01
We study the structure of stationary non-equilibrium states for interacting particle systems from a microscopic viewpoint. In particular we discuss two different discrete geometric constructions. We apply both of them to determine non reversible transition rates corresponding to a fixed invariant measure. The first one uses the equivalence of this problem with the construction of divergence free flows on the transition graph. Since divergence free flows are characterized by cyclic decompositions we can generate families of models from elementary cycles on the configuration space. The second construction is a functional discrete Hodge decomposition for translational covariant discrete vector fields. According to this, for example, the instantaneous current of any interacting particle system on a finite torus can be canonically decomposed in a gradient part, a circulation term and an harmonic component. All the three components are associated with functions on the configuration space. This decomposition is unique and constructive. The stationary condition can be interpreted as an orthogonality condition with respect to an harmonic discrete vector field and we use this decomposition to construct models having a fixed invariant measure.
International Nuclear Information System (INIS)
Zheng, Lei; Chellali, Reda; Schlesiger, Ralf; Meng, Ye; Baither, Dietmar; Schmitz, Guido
2015-01-01
Highlights: • Both isochronal and isothermal plasticity of Ni(Bi) alloy show minima. • Existing interpretations for isochronal and isothermal embrittlement are inadequate. • Both embrittlement is caused by thermo-induced non-equilibrium grain-boundary segregation of Bi. - Abstract: Isochronal and isothermal plasticity after thermal pre-treatments are obtained by tensile tests to characterize the embrittling behaviors of Ni(Bi) alloy. Both isochronal and isothermal plasticity show evident minima. Fractography observed by scanning electron microscopy displays intergranular fracture for samples of low plasticity. The microstructure is found to be free of precipitates within grains and at grain boundaries by focused ion beam and transmission electron microscopy. Atom probe analysis indicates a strong tendency of Bi segregation to grain boundaries. By these results, the existing interpretations are discussed to be inadequate and both embrittlement are confirmed to be identical in mechanism, i.e. thermo-induced non-equilibrium grain-boundary segregation of Bi
About the wind energetics development
International Nuclear Information System (INIS)
Strebkov, D.S.; Kharitonov, V.P.; Murugov, V.P.; Sokol'skij, A.K.
1996-01-01
The review of wind power energetics state in USA, Europe, Russia is given. The data of EC on wind power plants production in different periods are presented. The directions of scientific-research works with the purpose of increasing the level of wind power industry of Russia corresponding to economics demands were elaborated. (author). 8 refs., 3 tabs
Carbon nanostructure formation driven by energetic particles
International Nuclear Information System (INIS)
Zhu Zhiyuan; Gong Jinlong; Zhu Dezhang
2006-01-01
-treatment of multiwalled CNTs. A core-sheath structure of the diamond nanorods were identified, with the inner core being diamond crystal and outer shell being amorphous carbon. The diamond nanorods grow along diamond [110] direction. A growth mechanism was proposed. Under irradiation of 60 keV N + and Si + beams at room temperatures, we found that CNTs undergo a non-equilibrium amorphization with ion-generated displacement atoms jumping ballistically from graphite phase to amorphous phase. At high temperature (800 degree C), the recombination of vacancies and interstitials would repair the CNT structure and prevent the CNTs from amorphization. Furthermore, due to vacancy-mending in the graphitic shells, hence decreased shell diameter, and due to growing concentration of carbon atoms in the interior of the tube, the pressure in the inner parts of the system increases. However, unlike interstitials in spherical onions, carbon interstitials in CNTs can easily migrate away from regions with elevated pressure. Thus, radiation generated CNT amorphization can rarely be observed. By irradiating pre-amorphized carbon nanowires at high temperatures, the formation of carbon onions was clearly evidenced by high resolution transmission electron microscope (HRTEM). Such a two-step transformation model, i.e., amorphization at room temperatures and transformation from amorphous carbon to onion-like structure at high temperatures, demonstrated the structural evolution before early nucleation of diamond under energetic particles. A congruous designed compromise between nuclear and electron stopping power makes the diamond nucleation possible in carbon onions. The interconnected CNT networks have fundamental importance in nanoelectronics, integrated circuit connection and reinforcement of composite materials. At room temperatures, the morphological and structural evolution of CNT films under Si + ion beam (60 keV) irradiation was observed by scanning electron microscope and transmission
Energetic materials research using scanning electron microscopy
Elshout, J.J.M.H. van den; Duvalois, W.; Benedetto, G.L. Di; Bouma, R.H.B.; Heijden, A.E.D.M. van der
2016-01-01
A key-technique for the research of energetic materials is scanning electron microscopy. In this paper several examples are given of characterization studies on energetic materials, including a solid composite propellant formulation. Results of the characterization of energetic materials using
The location of energetic compartments affects energetic communication in cardiomyocytes
Directory of Open Access Journals (Sweden)
Rikke eBirkedal
2014-09-01
Full Text Available The heart relies on accurate regulation of mitochondrial energy supply to match energy demand. The main regulators are Ca2+ and feedback of ADP and Pi. Regulation via feedback has intrigued for decades. First, the heart exhibits a remarkable metabolic stability. Second, diffusion of ADP and other molecules is restricted specifically in heart and red muscle, where a fast feedback is needed the most. To explain the regulation by feedback, compartmentalization must be taken into account. Experiments and theoretical approaches suggest that cardiomyocyte energetic compartmentalization is elaborate with barriers obstructing diffusion in the cytosol and at the level of the mitochondrial outer membrane (MOM. A recent study suggests the barriers are organized in a lattice with dimensions in agreement with those of intracellular structures. Here, we discuss the possible location of these barriers. The more plausible scenario includes a barrier at the level of MOM. Much research has focused on how the permeability of MOM itself is regulated, and the importance of the creatine kinase system to facilitate energetic communication. We hypothesize that at least part of the diffusion restriction at the MOM level is not by MOM itself, but due to the close physical association between the sarcoplasmic reticulum (SR and mitochondria. This will explain why animals with a disabled creatine kinase system exhibit rather mild phenotype modifications. Mitochondria are hubs of energetics, but also ROS production and signaling. The close association between SR and mitochondria may form a diffusion barrier to ADP added outside a permeabilised cardiomyocyte. But in vivo, it is the structural basis for the mitochondrial-SR coupling that is crucial for the regulation of mitochondrial Ca2+-transients to regulate energetics, and for avoiding Ca2+-overload and irreversible opening of the mitochondrial permeability transition pore.
Experimental studies in non-equilibrium physics
Cressman, John Robert, Jr.
This work is a collection of three experiments aimed at studying different facets of non-equilibrium dynamics. Chapter I concerns strongly compressible turbulence, which turns out to be very different from incompressible turbulence. The focus is on the dispersion of contaminants in such a flow. This type of turbulence can be studied, at very low mach number, by measuring the velocity fields of particles that float on a turbulently stirred body of water. It turns out that in the absence of incompressibility, the turbulence causes particles to cluster rather than to disperse. The implications of the observations are far reaching and include the transport of pollutants on the oceans surface, phytoplankton growth, as well as industrial applications. Chapter II deals with the effects of polymer additives on drag reduction and turbulent suppression, a well-known phenomenon that is not yet understood. In an attempt to simplify the problem, the effects of a polymer additive were investigated in a vortex street formed in a flowing soap film. Measurements suggest that an increase in elongational viscosity is responsible for a substantial reduction in periodic velocity fluctuations. This study also helps to illuminate the mechanism responsible for vortex separation in the wake of a bluff body. Chapter III describes an experiment designed to test a theoretical approach aimed at generalizing the classical fluctuation dissipation theorem (FDT). This theorem applies to systems driven only slightly away from thermal equilibrium, whereas ours, a liquid crystal under-going electroconvection, is so strongly driven, that the FDT does not apply. Both theory and experiment focus on the flux in global power fluctuations. Physical limitations did not permit a direct test of the theory, however it was possible to establish several interesting characteristics of the system: the source of the fluctuations is the transient defect structures that are generated when the system is driven hard
A constitutive rheological model for agglomerating blood derived from nonequilibrium thermodynamics
Tsimouri, Ioanna Ch.; Stephanou, Pavlos S.; Mavrantzas, Vlasis G.
2018-03-01
Red blood cells tend to aggregate in the presence of plasma proteins, forming structures known as rouleaux. Here, we derive a constitutive rheological model for human blood which accounts for the formation and dissociation of rouleaux using the generalized bracket formulation of nonequilibrium thermodynamics. Similar to the model derived by Owens and co-workers ["A non-homogeneous constitutive model for human blood. Part 1. Model derivation and steady flow," J. Fluid Mech. 617, 327-354 (2008)] through polymer network theory, each rouleau in our model is represented as a dumbbell; the corresponding structural variable is the conformation tensor of the dumbbell. The kinetics of rouleau formation and dissociation is treated as in the work of Germann et al. ["Nonequilibrium thermodynamic modeling of the structure and rheology of concentrated wormlike micellar solutions," J. Non-Newton. Fluid Mech. 196, 51-57 (2013)] by assuming a set of reversible reactions, each characterized by a forward and a reverse rate constant. The final set of evolution equations for the microstructure of each rouleau and the expression for the stress tensor turn out to be very similar to those of Owens and co-workers. However, by explicitly considering a mechanism for the formation and breakage of rouleaux, our model further provides expressions for the aggregation and disaggregation rates appearing in the final transport equations, which in the kinetic theory-based network model of Owens were absent and had to be specified separately. Despite this, the two models are found to provide similar descriptions of experimental data on the size distribution of rouleaux.
Research@ARL: Energy & Energetics
2012-06-01
CuO , CoFe2O4 and Co3O4, 10 carbon supported Pt and Au,11 and carbon supported pyrolyzed Co macrocyles,2 have not shown much improvement to the Li/O2...behavior in semiconductors ,7, 8 C60 fullerene,9 sodium azide21 as well as elements 10 and energetic materials.19 Despite the critical scientific insight
Life cycles of energetic systems
International Nuclear Information System (INIS)
Adnot, Jerome; Marchio, Dominique; Riviere, Philippe; Duplessis, B.; Rabl, A.; Glachant, M.; Aggeri, F.; Benoist, A.; Teulon, H.; Daude, J.
2012-01-01
This collective publication aims at being a course for students in engineering of energetic systems, i.e. at learning how to decide to accept or discard a project, to select the most efficient system, to select the optimal system, to select the optimal combination of systems, and to classify independent systems. Thus, it presents methods to analyse system life cycle from an energetic, economic and environmental point of view, describes how to develop an approach to the eco-design of an energy consuming product, how to understand the importance of hypotheses behind abundant and often contradicting publicised results, and to be able to criticise or to put in perspective one's own analysis. The first chapters thus recall some aspects of economic calculation, introduce the assessment of investment and exploitation costs of energetic systems, describe how to assess and internalise environmental costs, present the territorial carbon assessment, discuss the use of the life cycle assessment, and address the issue of environmental management at a product scale. The second part proposes various case studies: an optimal fleet of thermal production of electric power, the eco-design of a refrigerator, the economic and environmental assessment of wind farms
Bose, Deepak
2012-01-01
The design of entry vehicles requires predictions of aerothermal environment during the hypersonic phase of their flight trajectories. These predictions are made using computational fluid dynamics (CFD) codes that often rely on physics and chemistry models of nonequilibrium processes. The primary processes of interest are gas phase chemistry, internal energy relaxation, electronic excitation, nonequilibrium emission and absorption of radiation, and gas-surface interaction leading to surface recession and catalytic recombination. NASAs Hypersonics Project is advancing the state-of-the-art in modeling of nonequilibrium phenomena by making detailed spectroscopic measurements in shock tube and arcjets, using ab-initio quantum mechanical techniques develop fundamental chemistry and spectroscopic databases, making fundamental measurements of finite-rate gas surface interactions, implementing of detailed mechanisms in the state-of-the-art CFD codes, The development of new models is based on validation with relevant experiments. We will present the latest developments and a roadmap for the technical areas mentioned above
Work fluctuation and total entropy production in nonequilibrium processes.
Funo, Ken; Shitara, Tomohiro; Ueda, Masahito
2016-12-01
Work fluctuation and total entropy production play crucial roles in small thermodynamic systems subject to large thermal fluctuations. We investigate a trade-off relation between them in a nonequilibrium situation in which a system starts from an arbitrary nonequilibrium state. We apply a variational method to study this problem and find a stationary solution against variations over protocols that describe the time dependence of the Hamiltonian of the system. Using the stationary solution, we find the minimum of the total entropy production for a given amount of work fluctuation. An explicit protocol that achieves this is constructed from an adiabatic process followed by a quasistatic process. The obtained results suggest how one can control the nonequilibrium dynamics of the system while suppressing its work fluctuation and total entropy production.
Nonequilibrium Dynamical Mean-Field Theory for Bosonic Lattice Models
Directory of Open Access Journals (Sweden)
Hugo U. R. Strand
2015-03-01
Full Text Available We develop the nonequilibrium extension of bosonic dynamical mean-field theory and a Nambu real-time strong-coupling perturbative impurity solver. In contrast to Gutzwiller mean-field theory and strong-coupling perturbative approaches, nonequilibrium bosonic dynamical mean-field theory captures not only dynamical transitions but also damping and thermalization effects at finite temperature. We apply the formalism to quenches in the Bose-Hubbard model, starting from both the normal and the Bose-condensed phases. Depending on the parameter regime, one observes qualitatively different dynamical properties, such as rapid thermalization, trapping in metastable superfluid or normal states, as well as long-lived or strongly damped amplitude oscillations. We summarize our results in nonequilibrium “phase diagrams” that map out the different dynamical regimes.
Inviscid flux-splitting algorithms for real gases with non-equilibrium chemistry
Shuen, Jian-Shun; Liou, Meng-Sing; Van Leer, Bram
1990-01-01
Formulations of inviscid flux splitting algorithms for chemical nonequilibrium gases are presented. A chemical system for air dissociation and recombination is described. Numerical results for one-dimensional shock tube and nozzle flows of air in chemical nonequilibrium are examined.
Nonequilibrium Statistical Mechanics in One Dimension
Privman, Vladimir
2005-08-01
Part I. Reaction-Diffusion Systems and Models of Catalysis; 1. Scaling theories of diffusion-controlled and ballistically-controlled bimolecular reactions S. Redner; 2. The coalescence process, A+A->A, and the method of interparticle distribution functions D. ben-Avraham; 3. Critical phenomena at absorbing states R. Dickman; Part II. Kinetic Ising Models; 4. Kinetic ising models with competing dynamics: mappings, correlations, steady states, and phase transitions Z. Racz; 5. Glauber dynamics of the ising model N. Ito; 6. 1D Kinetic ising models at low temperatures - critical dynamics, domain growth, and freezing S. Cornell; Part III. Ordering, Coagulation, Phase Separation; 7. Phase-ordering dynamics in one dimension A. J. Bray; 8. Phase separation, cluster growth, and reaction kinetics in models with synchronous dynamics V. Privman; 9. Stochastic models of aggregation with injection H. Takayasu and M. Takayasu; Part IV. Random Sequential Adsorption and Relaxation Processes; 10. Random and cooperative sequential adsorption: exactly solvable problems on 1D lattices, continuum limits, and 2D extensions J. W. Evans; 11. Lattice models of irreversible adsorption and diffusion P. Nielaba; 12. Deposition-evaporation dynamics: jamming, conservation laws and dynamical diversity M. Barma; Part V. Fluctuations In Particle and Surface Systems; 13. Microscopic models of macroscopic shocks S. A. Janowsky and J. L. Lebowitz; 14. The asymmetric exclusion model: exact results through a matrix approach B. Derrida and M. R. Evans; 15. Nonequilibrium surface dynamics with volume conservation J. Krug; 16. Directed walks models of polymers and wetting J. Yeomans; Part VI. Diffusion and Transport In One Dimension; 17. Some recent exact solutions of the Fokker-Planck equation H. L. Frisch; 18. Random walks, resonance, and ratchets C. R. Doering and T. C. Elston; 19. One-dimensional random walks in random environment K. Ziegler; Part VII. Experimental Results; 20. Diffusion
Microstructured polymer optical fibres
Large, Maryanne; Barton, Geoff; van Eijkelenborg, Martijn A
2008-01-01
Microstructured Polymer Optical Fibres describes the optical properties of microstructured fibres, how they are made and modelled, and outlines some potential applications. These applications include areas where polymer fibres are already used, such as high-data rate transmission for Fibre-to-the Home or within cars, as well as completely new areas such as the photonic bandgap transmission of ""difficult"" wavelengths. Emphasising a conceptual understanding of the underlying physics, Microstructured Polymer Optical Fibres is clearly written, and includes numerous illustrations. It provides an
Generalization of the second law for a nonequilibrium initial state
Energy Technology Data Exchange (ETDEWEB)
Hasegawa, H.-H., E-mail: hhh@mx.ibaraki.ac.j [Department of Mathematical Sciences, Ibaraki University, Bunkyo, Mito 310-8512 (Japan); Ishikawa, J.; Takara, K. [Department of Mathematical Sciences, Ibaraki University, Bunkyo, Mito 310-8512 (Japan); Driebe, D.J. [Division of Math, Science and Technology, Nova Southeastern University, Fort Lauderdale, FL 33314 (United States)
2010-02-08
We generalize the second law of thermodynamics in its maximum work formulation for a nonequilibrium initial distribution. It is found that in an isothermal process, the Boltzmann relative entropy (H-function) is not just a Lyapunov function but also tells us the maximum work that may be gained from a nonequilibrium initial state. The generalized second law also gives a fundamental relation between work and information. It is valid even for a small Hamiltonian system not in contact with a heat reservoir but with an effective temperature determined by the isentropic condition. Our relation can be tested in the Szilard engine, which will be realized in the laboratory.
Limiting processes in non-equilibrium classical statistical mechanics
International Nuclear Information System (INIS)
Jancel, R.
1983-01-01
After a recall of the basic principles of the statistical mechanics, the results of ergodic theory, the transient at the thermodynamic limit and his link with the transport theory near the equilibrium are analyzed. The fundamental problems put by the description of non-equilibrium macroscopic systems are investigated and the kinetic methods are stated. The problems of the non-equilibrium statistical mechanics are analyzed: irreversibility and coarse-graining, macroscopic variables and kinetic description, autonomous reduced descriptions, limit processes, BBGKY hierarchy, limit theorems [fr
Imaginary-time formulation of strongly correlated nonequilibrium
Heary, Ryan Joseph
Strongly correlated nanostructures and lattices of electrons are studied when these systems reside in a steady-state nonequilibrium. Much of the work done to date has made use of the nonequilibrium real-time Keldysh Green function technique. These methods include: the Keldysh Green function perturbation theory, time-dependent numerical renormalization group, density matrix renormalization group, and diagrammatic quantum Monte Carlo. In the special case of steady-state nonequilibrium we construct an imaginary-time theory. The motivation to do this is simple: there exist an abundant number of well-established strongly correlated computational solvers for imaginary-time theory and perturbation theory on the imaginary-time contour is much more straightforward than that of the real-time contour. The first model system we focus on is a strongly interacting quantum dot situated between source and drain electron reservoirs. The steady-state nonequilibrium boundary condition is established by applying a voltage bias phi across the reservoirs, in turn modifying the chemical potentials of the leads. For a symmetric voltage drop we have mu source = phi/2 and mudrain = -phi/2. The dynamics of the electrons are governed by the Hamiltonian Ĥ which is inherently independent of the imbalance in the source and drain chemical potentials. The statistics though are determined by the operator Ĥ-Ŷ , where Ŷ imposes the nonequilibrium boundary condition. We show that it is possible to construct a single effective Hamiltonian K̂ able to describe both the dynamics and statistics of the system. Upon formulating the theory we explicitly show that it is consistent with the real-time Keldysh theory both formally and through an example using perturbation theory. In these systems there exists a strong interplay between the interactions and nonequilibrium leading to novel nonperturbative phenomena. Therefore, we combine our theory with the Hirsch-Fye quantum Monte Carlo algorithm to study
Time Dependent Hartree Fock Equation: Gateway to Nonequilibrium Plasmas
International Nuclear Information System (INIS)
Dufty, James W.
2007-01-01
This is the Final Technical Report for DE-FG02-2ER54677 award 'Time Dependent Hartree Fock Equation - Gateway to Nonequilibrium Plasmas'. Research has focused on the nonequilibrium dynamics of electrons in the presence of ions, both via basic quantum theory and via semi-classical molecular dynamics (MD) simulation. In addition, fundamental notions of dissipative dynamics have been explored for models of grains and dust, and for scalar fields (temperature) in turbulent edge plasmas. The specific topics addressed were Quantum Kinetic Theory for Metallic Clusters, Semi-classical MD Simulation of Plasmas , and Effects of Dissipative Dynamics.
Nonequilibrium work energy relation for non-Hamiltonian dynamics.
Mandal, Dibyendu; DeWeese, Michael R
2016-04-01
Recent years have witnessed major advances in our understanding of nonequilibrium processes. The Jarzynski equality, for example, provides a link between equilibrium free energy differences and finite-time nonequilibrium dynamics. We propose a generalization of this relation to non-Hamiltonian dynamics, relevant for active matter systems, continuous feedback, and computer simulation. Surprisingly, this relation allows us to calculate the free energy difference between the desired initial and final equilibrium states using arbitrary dynamics. As a practical matter, this dissociation between the dynamics and the initial and final states promises to facilitate a range of techniques for free energy estimation in a single universal expression.
Convection with local thermal non-equilibrium and microfluidic effects
Straughan, Brian
2015-01-01
This book is one of the first devoted to an account of theories of thermal convection which involve local thermal non-equilibrium effects, including a concentration on microfluidic effects. The text introduces convection with local thermal non-equilibrium effects in extraordinary detail, making it easy for readers newer to the subject area to understand. This book is unique in the fact that it addresses a large number of convection theories and provides many new results which are not available elsewhere. This book will be useful to researchers from engineering, fluid mechanics, and applied mathematics, particularly those interested in microfluidics and porous media.
Continuous media with microstructure
2010-01-01
This book discusses the extension of classical continuum models. To the first class addressed belong various thermodynamic models of multicomponent systems, and to the second class belong primarily microstructures created by phase transformations.
Harris, William M; Brinkman, Kyle S; Lin, Ye; Su, Dong; Cocco, Alex P; Nakajo, Arata; DeGostin, Matthew B; Chen-Wiegart, Yu-chen Karen; Wang, Jun; Chen, Fanglin; Chu, Yong S; Chiu, Wilson K S
2014-05-07
The microstructure and connectivity of the ionic and electronic conductive phases in composite ceramic membranes are directly related to device performance. Transmission electron microscopy (TEM) including chemical mapping combined with X-ray nanotomography (XNT) have been used to characterize the composition and 3-D microstructure of a MIEC composite model system consisting of a Ce0.8Gd0.2O2 (GDC) oxygen ion conductive phase and a CoFe2O4 (CFO) electronic conductive phase. The microstructural data is discussed, including the composition and distribution of an emergent phase which takes the form of isolated and distinct regions. Performance implications are considered with regards to the design of new material systems which evolve under non-equilibrium operating conditions.
Energy Technology Data Exchange (ETDEWEB)
Haschke, J M; Siekhaus, W J
2009-02-11
Static concentrations of plutonium oxidation states in solution and at surfaces in oxide-water systems are identified as non-equilibrium steady states. These kinetically controlled systems are described by redox cycles based on irreversible disproportionation of Pu(IV), Pu(V), and Pu(VI) in OH-bridged intermediate complexes and at OH-covered oxide surfaces. Steady state is fixed by continuous redox cycles driven by radioactivity-promoted electron-transfer and energetically favorable reactions of Pu(III) and Pu(VII) disproportionation products with H2O. A model based on the redox cycles accounts for the high steady-state [Pu] coexisting with Pu(IV) hydrous oxide at pH 0-15 and for predominance of Pu(V) and Pu(VI) in solution. The steady-state [Pu] depends on pH and the surface area of oxide in solution, but not on the initial Pu oxidation state. PuO{sub 2+x} formation is attributed to high Pu(V) concentrations existing at water-exposed oxide surfaces. Results infer that migration of Pu in an aqueous environment is controlled by kinetic factors unique to that site and that the predominant oxidation states in solution are Pu(V) and Pu(VI).
International Nuclear Information System (INIS)
Haschke, J.M.; Siekhaus, W.J.
2009-01-01
Static concentrations of plutonium oxidation states in solution and at surfaces in oxide-water systems are identified as non-equilibrium steady states. These kinetically controlled systems are described by redox cycles based on irreversible disproportionation of Pu(IV), Pu(V), and Pu(VI) in OH-bridged intermediate complexes and at OH-covered oxide surfaces. Steady state is fixed by continuous redox cycles driven by radioactivity-promoted electron-transfer and energetically favorable reactions of Pu(III) and Pu(VII) disproportionation products with H2O. A model based on the redox cycles accounts for the high steady-state (Pu) coexisting with Pu(IV) hydrous oxide at pH 0-15 and for predominance of Pu(V) and Pu(VI) in solution. The steady-state (Pu) depends on pH and the surface area of oxide in solution, but not on the initial Pu oxidation state. PuO 2+x formation is attributed to high Pu(V) concentrations existing at water-exposed oxide surfaces. Results infer that migration of Pu in an aqueous environment is controlled by kinetic factors unique to that site and that the predominant oxidation states in solution are Pu(V) and Pu(VI)
Energetics of the midlatitude thermosphere
Stolarski, R. S.
1976-01-01
Thermospheric energetics is examined from the point of view of atomic and molecular processes which convert solar EUV radiative energy into kinetic energy of the ambient electron, ion, and neutral gases. The energy flow from photon to photoelectron-ion pair through energy loss and ion-molecule transfer to eventual electron-ion recombination is traced in detail. Upper and lower bounds are placed on the efficiency of conversion of radiative to thermal energy. Implications for the question of consistency of measured solar EUV fluxes and ionospheric models are discussed.
Energetic particles in the heliosphere
Simnett, George M
2017-01-01
This monograph traces the development of our understanding of how and where energetic particles are accelerated in the heliosphere and how they may reach the Earth. Detailed data sets are presented which address these topics. The bulk of the observations are from spacecraft in or near the ecliptic plane. It is timely to present this subject now that Voyager-1 has entered the true interstellar medium. Since it seems unlikely that there will be a follow-on to the Voyager programme any time soon, the data we already have regarding the outer heliosphere are not going to be enhanced for at least 40 years.
Some recent developments in non-equilibrium statistical physics
Indian Academy of Sciences (India)
for molecular motors and the asymmetric exclusion process which is a basic example of a driven lattice gas. Keywords. Thermodynamics; non-equilibrium mechanics; Brownian motion; molecular motors; Gallavotti–Cohen fluctuation theorem; Jarzynski's work relation. PACS Nos 05.70.Ln; 05.40.-a; 87.16.Nn. 1. Introduction.
Conserving GW scheme for nonequilibrium quantum transport in molecular contacts
DEFF Research Database (Denmark)
Thygesen, Kristian Sommer; Rubio, Angel
2008-01-01
We give a detailed presentation of our recent scheme to include correlation effects in molecular transport calculations using the nonequilibrium Keldysh formalism. The scheme is general and can be used with any quasiparticle self-energy, but for practical reasons, we mainly specialize to the so-c...
Spacecraft Sterilization Using Non-Equilibrium Atmospheric Pressure Plasma
Cooper, Moogega; Vaze, Nachiket; Anderson, Shawn; Fridman, Gregory; Vasilets, Victor N.; Gutsol, Alexander; Tsapin, Alexander; Fridman, Alexander
2007-01-01
As a solution to chemically and thermally destructive sterilization methods currently used for spacecraft, non-equilibrium atmospheric pressure plasmas are used to treat surfaces inoculated with Bacillus subtilis and Deinococcus radiodurans. Evidence of significant morphological changes and reduction in viability due to plasma exposure will be presented, including a 4-log reduction of B. subtilis after 2 minutes of dielectric barrier discharge treatment.
Canonical structure of dynamical fluctuations in mesoscopic nonequilibrium steady states
Czech Academy of Sciences Publication Activity Database
Maes, C.; Netočný, Karel
2008-01-01
Roč. 82, č. 3 (2008), 30003/1-30003/6 ISSN 0295-5075 R&D Projects: GA ČR GC202/07/J051 Institutional research plan: CEZ:AV0Z10100520 Keywords : nonequilibrium fluctuations * steady state * Onsager- Machlup theory Subject RIV: BE - Theoretical Physics Impact factor: 2.203, year: 2008
Fluctuations and large deviations in non-equilibrium systems
Indian Academy of Sciences (India)
a possible way of extending the notion of free energy to non-equilibrium systems. This large deviation function of the density can be calculated explicitly for exclusion models in one dimension with open boundary conditions. For these models, one can also obtain the distribution of the current of particles flowing through the ...
Nonequilibrium relaxation method – An alternative simulation strategy
Indian Academy of Sciences (India)
the results to infinite system. This equilibrium method traces over the standard theory of the thermal statistical mechanics, and over the idea of the thermodynamic limit. Recently, an alternative simulation strategy has been developed, which analyzes the nonequilibrium relaxation (NER) process. It is called the NER method.
Nonequilibrium Enhances Adaptation Efficiency of Stochastic Biochemical Systems.
Directory of Open Access Journals (Sweden)
Chen Jia
Full Text Available Adaptation is a crucial biological function possessed by many sensory systems. Early work has shown that some influential equilibrium models can achieve accurate adaptation. However, recent studies indicate that there are close relationships between adaptation and nonequilibrium. In this paper, we provide an explanation of these two seemingly contradictory results based on Markov models with relatively simple networks. We show that as the nonequilibrium driving becomes stronger, the system under consideration will undergo a phase transition along a fixed direction: from non-adaptation to simple adaptation then to oscillatory adaptation, while the transition in the opposite direction is forbidden. This indicates that although adaptation may be observed in equilibrium systems, it tends to occur in systems far away from equilibrium. In addition, we find that nonequilibrium will improve the performance of adaptation by enhancing the adaptation efficiency. All these results provide a deeper insight into the connection between adaptation and nonequilibrium. Finally, we use a more complicated network model of bacterial chemotaxis to validate the main results of this paper.
Fluctuations and large deviations in non-equilibrium systems
Indian Academy of Sciences (India)
For systems in contact with two reservoirs at different densities or with two thermostats at different temperatures, the large deviation function of the density gives a possible way of extending the notion of free energy to non-equilibrium systems. This large deviation function of the density can be calculated explicitly for ...
Principle of Entropy Maximization for Nonequilibrium Steady States
DEFF Research Database (Denmark)
Shapiro, Alexander; Stenby, Erling Halfdan
2002-01-01
The goal of this contribution is to find out to what extent the principle of entropy maximization, which serves as a basis for the equilibrium thermodynamics, may be generalized onto non-equilibrium steady states. We prove a theorem that, in the system of thermodynamic coordinates, where entropy...
Coherence enhanced quantum metrology in a nonequilibrium optical molecule
Wang, Zhihai; Wu, Wei; Cui, Guodong; Wang, Jin
2018-03-01
We explore the quantum metrology in an optical molecular system coupled to two environments with different temperatures, using a quantum master equation beyond secular approximation. We discover that the steady-state coherence originating from and sustained by the nonequilibrium condition can enhance quantum metrology. We also study the quantitative measures of the nonequilibrium condition in terms of the curl flux, heat current and entropy production at the steady state. They are found to grow with temperature difference. However, an apparent paradox arises considering the contrary behaviors of the steady-state coherence and the nonequilibrium measures in relation to the inter-cavity coupling strength. This paradox is resolved by decomposing the heat current into a population part and a coherence part. Only the latter, the coherence part of the heat current, is tightly connected to the steady-state coherence and behaves similarly with respect to the inter-cavity coupling strength. Interestingly, the coherence part of the heat current flows from the low-temperature reservoir to the high-temperature reservoir, opposite to the direction of the population heat current. Our work offers a viable way to enhance quantum metrology for open quantum systems through steady-state coherence sustained by the nonequilibrium condition, which can be controlled and manipulated to maximize its utility. The potential applications go beyond quantum metrology and extend to areas such as device designing, quantum computation and quantum technology in general.
D.C.-arc plasma generator for nonequilibrium plasmachemical processes
International Nuclear Information System (INIS)
Kvaltin, J.
1990-06-01
The analysis is made of the conditions for generation of nonequilibrium plasma in a plasmachemical reactor, and the design is described of a d.c. arc plasma generator based on the integral criterion. Results of measuring potentials on the plasma column of this generator are presented. (author)
On the theory of non-equilibrium hydrodynamic fluctuations
International Nuclear Information System (INIS)
Peletminskij, S.V.; Plokhov, S.S.; Prikhod'ko, V.I.
1981-01-01
Using the method of abbreviated description a microscopic theory of non-equilibrium fluctuations with a great radius of correlations, which permits to study fluctuation kinetics at t>>tausub(r)(tausub(r) is relaxation time) is built. General formula, describing the degree character of approximation to the state of statistical equilibrium of mean values of arbitrary quasilocal operators, are obtained [ru
Electron systems out of equilibrium: nonequilibrium Green's function approach
Czech Academy of Sciences Publication Activity Database
Špička, Václav; Velický, Bedřich; Kalvová, Anděla
2014-01-01
Roč. 28, č. 23 (2014), "1430013-1"-"1430013-103" ISSN 0217-9792 R&D Projects: GA ČR GAP204/12/0897 Institutional support: RVO:68378271 Keywords : nonequilibrium statistical physics * transients * quantum transport theory Subject RIV: BE - Theoretical Physics Impact factor: 0.937, year: 2014
Classical Orbital Paramagnetism in Non-equilibrium Steady State
Indian Academy of Sciences (India)
Avinash A. Deshpande
2017-09-12
Sep 12, 2017 ... Classical Orbital Paramagnetism in Non-equilibrium Steady State. AVINASH A. DESHPANDE. ∗ and N. KUMAR. Raman Research Institute, Bangalore 560 080, India. ∗. Corresponding author. E-mail: desh@rri.res.in. MS received 25 March 2017; accepted 31 July 2017; published online 12 September ...
Fluctuation theorems and orbital magnetism in nonequilibrium state
Indian Academy of Sciences (India)
We study Langevin dynamics of a driven charged particle in the presence as well as in the absence of magnetic field. We discuss the validity of various work fluctuation theorems using different model potentials and external drives. We also show that one can generate an orbital magnetic moment in a nonequilibrium state ...
Fluctuation theorems and orbital magnetism in nonequilibrium state
Indian Academy of Sciences (India)
Fluctuation theorem; Jarzynski equality; orbital magnetism. PACS Nos 05.70.Ln; 05.40.Jc; 05.40.-a; 05.40.Ca. 1. Introduction. Recent developments in nonequilibrium statistical mechanics has led to the discov- ery of several rigorous theorems for systems far away from equilibrium [1–10]. The fluctuation theorems describe ...
Simulation and comparison of equilibrium and nonequilibrium stage ...
African Journals Online (AJOL)
In the present study, two distinctly different approaches are followed for modelling of reactive distillation column, the equilibrium stage model and the nonequilibrium stage model. These models are simulated with a computer code developed in the present study using MATLAB programming. In the equilibrium stage models, ...
On the forces and fluxes in non-equilibrium thermodynamics
International Nuclear Information System (INIS)
Kitahara, Kazuo
1986-01-01
A formulation of non-equilibrium thermodynamics of continuum systems based on local equilibrium assumption is reported. Thermodynamic forces are defined from a generalized local entropy and irreversible fluxes are defined as non-advective parts of fluxes of conservative quantities. The validity of the general evolution criterion and its generalization is discussed. (author)
Energetic Techniques For Planetary Defense
Barbee, B.; Bambacus, M.; Bruck Syal, M.; Greenaugh, K. C.; Leung, R. Y.; Plesko, C. S.
2017-12-01
Near-Earth Objects (NEOs) are asteroids and comets whose heliocentric orbits tend to approach or cross Earth's heliocentric orbit. NEOs of various sizes periodically collide with Earth, and efforts are currently underway to discover, track, and characterize NEOs so that those on Earth-impacting trajectories are discovered far enough in advance that we would have opportunities to deflect or destroy them prior to Earth impact, if warranted. We will describe current efforts by the National Aeronautics and Space Administration (NASA) and the National Nuclear Security Administration (NNSA) to assess options for energetic methods of deflecting or destroying hazardous NEOs. These methods include kinetic impactors, which are spacecraft designed to collide with an NEO and thereby alter the NEO's trajectory, and nuclear engineering devices, which are used to rapidly vaporize a layer of NEO surface material. Depending on the amount of energy imparted, this can result in either deflection of the NEO via alteration of its trajectory, or robust disruption of the NEO and dispersal of the remaining fragments. We have studied the efficacies and limitations of these techniques in simulations, and have combined the techniques with corresponding spacecraft designs and mission designs. From those results we have generalized planetary defense mission design strategies and drawn conclusions that are applicable to a range of plausible scenarios. We will present and summarize our research efforts to date, and describe approaches to carrying out planetary defense missions with energetic NEO deflection or disruption techniques.
Armor Solutions for Energetic and Non-Energetic Novel Defeat Mechanisms
2015-09-28
Final Technical Status Report For DOTC-13-01-INIT112 Armor Solutions for Energetic and Non-Energetic Novel Defeat Mechanisms Reporting...REPORT TYPE Final 3. DATES COVERED 4. TITLE AND SUBTITLE Final Report: Armor Solutions for Energetic and Non-Energetic Novel Defeat...distribution unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Summary of prototyping efforts for next generation armor designs using advanced
Fracture mechanics and microstructures
International Nuclear Information System (INIS)
Gee, M.G.; Morrell, R.
1986-01-01
The influence of microstructure on defects in ceramics, and the consequences of their presence for the application of fracture mechanics theories are reviewed. The complexities of microstructures, especially the multiphase nature, the crystallographic anisotropy and the resultant anisotropic physical properties, and the variation of microstructure and surface finish from point to point in real components, all lead to considerable uncertainties in the actual performance of any particular component. It is concluded that although the concepts of fracture mechanics have been and will continue to be most useful for the qualitative explanation of fracture phenomena, the usefulness as a predictive tool with respect to most existing types of material is limited by the interrelation between material microstructure and mechanical properties. At present, the only method of eliminating components with unsatisfactory mechanical properties is to proof-test them, despite the fact that proof-testing itself is limited in ability to cope with changes to the component in service. The aim of the manufacturer must be to improve quality and consistency within individual components, from component to component, and from batch to batch. The aim of the fracture specialist must be to study longer-term properties to improve the accuracy of behaviour predictions with a stronger data base. Materials development needs to concentrate on obtaining defect-free materials that can be translated into more-reliable products, using our present understanding of the influence of microstructure on strength and toughness
Hülsenberg, Dagmar; Bismarck, Alexander
2008-01-01
As microstructured glass becomes increasingly important for microsystems technology, the main application fields include micro-fluidic systems, micro-analysis systems, sensors, micro-actuators and implants. And, because glass has quite distinct properties from silicon, PMMA and metals, applications exist where only glass devices meet the requirements. The main advantages of glass derive from its amorphous nature, the precondition for its - theoretically - direction-independent geometric structurability. Microstructuring of Glasses deals with the amorphous state, various glass compositions and their properties, the interactions between glasses and the electromagnetic waves used to modify it. Also treated in detail are methods for influencing the geometrical microstructure of glasses by mechanical, chemical, thermal, optical, and electrical treatment, and the methods and equipment required to produce actual microdevices.
Theoretical studies on energetic materials bearing pentaflurosulphyl ...
Indian Academy of Sciences (India)
Heats of formation (HOF) for a series of energetic materials containing SF5 group were studied by density functional theory. Results show that HOFs increase with the augmention of field effects of substituted groups. Addition of furazan or furoxan ring increases HOF of the energetic materials. All the SF5-containing ...
Theoretical studies on energetic materials bearing pentaflurosulphyl
Indian Academy of Sciences (India)
Heats of formation (HOF) for a series of energetic materials containing SF5 group were studied by density functional theory. Results show that HOFs increase with the augmention of field effects of substituted groups. Addition of furazan or furoxan ring increases HOF of the energetic materials. All the SF5-containing ...
Multiscale measurement of cardiac energetics.
Goo, Soyeon; Pham, Toan; Han, Jun-Chiew; Nielsen, Poul; Taberner, Andrew; Hickey, Anthony; Loiselle, Denis
2013-09-01
Herein we describe our laboratories' experimental methods for interrogating cardiac energetics at the organ (whole heart), tissue (trabecula) and perforated fibre (mitochondrial) levels. In whole heart and trabecula experiments, we focus on measuring pressure-volume (force-length) work and oxygen consumption (heat production) from which mechanical efficiency is derived. In both preparations (i.e. across scales differing by three orders of magnitude) we find efficiency values of 10%-15%. Mitochondrial experiments invoke a trio of titration protocols to yield information on oxygen consumption, ATP flux, membrane potential, electron leak and reactive oxygen species production, the latter two of which index energy transfer inefficiencies. Copyright © 2013 Wiley Publishing Asia Pty Ltd.
Energetics of borelike internal waves
Henyey, Frank S.; Hoering, Antje
1997-02-01
The net integrated energy flux into a train of internal waves is evaluated in a two-layer model. The nonzero value for this integral results from the difference in the stratification between the initial and final state, similar to the energy supply to a surface bore. We apply this expression to waves measured by Wesson and Gregg [1988] in the Strait of Gibraltar and to waves measured by Farmer and Smith [1980] in Knight Inlet. We find the energy supply to be important to the energetics, but the data do not allow a definitive test of the conjecture that the primary energy balance is between this supply and dissipation. We contrast our conjecture to the solitary-wave considerations of Bogucki and Garrett [1993].
Cosmic Ray Energetics and Mass
Baylon cardiel, J L; Wallace, K C; Anderson, T B; Copley, M
The cosmic-ray energetics and mass (CREAM) investigation is designed to measure cosmic-ray composition to the supernova energy scale of 10$^{15}$ eV in a series of ultra long duration balloon (ULDB) flights. The first flight is planned to be launched from Antarctica in December 2004. The goal is to observe cosmic-ray spectral features and/or abundance changes that might signify a limit to supernova acceleration. The particle ($\\{Z}$) measurements will be made with a timing-based charge detector and a pixelated silicon charge detector to minimize the effect of backscatter from the calorimeter. The particle energy measurements will be made with a transition radiation detector (TRD) for $\\{Z}$ > 3 and a sampling tungsten/scintillator calorimeter for $\\{Z}$ $\\geq$1 particles, allowing inflight cross calibration of the two detectors. The status of the payload construction and flight preparation are reported in this paper.
Hierarchical microstructures in CZT
International Nuclear Information System (INIS)
Sundaram, S.K.; Henager, C.H.; Edwards, D.J.; Schemer-Kohrn, A.L.; Bliss, M.; Riley, B.R.; Toloczko, M.B.; Lynn, K.G.
2011-01-01
Advanced characterization tools, such as electron backscatter diffraction and transmitted IR microscopy, are being applied to study critical microstructural features and orientation relations in as-grown CZT crystals to aid in understanding the relation between structure and properties in radiation detectors. Even carefully prepared single crystals of CZT contain regions of slight misorientation, Te-particles, and dislocation networks that must be understood for more accurate models of detector response. This paper describes initial research at PNNL into the hierarchy of microstructures observed in CZT grown via the vertical gradient freeze or vertical Bridgman method at PNNL and WSU.
Potential landscape and flux field theory for turbulence and nonequilibrium fluid systems
Wu, Wei; Zhang, Feng; Wang, Jin
2018-02-01
Turbulence is a paradigm for far-from-equilibrium systems without time reversal symmetry. To capture the nonequilibrium irreversible nature of turbulence and investigate its implications, we develop a potential landscape and flux field theory for turbulent flow and more general nonequilibrium fluid systems governed by stochastic Navier-Stokes equations. We find that equilibrium fluid systems with time reversibility are characterized by a detailed balance constraint that quantifies the detailed balance condition. In nonequilibrium fluid systems with nonequilibrium steady states, detailed balance breaking leads directly to a pair of interconnected consequences, namely, the non-Gaussian potential landscape and the irreversible probability flux, forming a 'nonequilibrium trinity'. The nonequilibrium trinity characterizes the nonequilibrium irreversible essence of fluid systems with intrinsic time irreversibility and is manifested in various aspects of these systems. The nonequilibrium stochastic dynamics of fluid systems including turbulence with detailed balance breaking is shown to be driven by both the non-Gaussian potential landscape gradient and the irreversible probability flux, together with the reversible convective force and the stochastic stirring force. We reveal an underlying connection of the energy flux essential for turbulence energy cascade to the irreversible probability flux and the non-Gaussian potential landscape generated by detailed balance breaking. Using the energy flux as a center of connection, we demonstrate that the four-fifths law in fully developed turbulence is a consequence and reflection of the nonequilibrium trinity. We also show how the nonequilibrium trinity can affect the scaling laws in turbulence.
Recrystallization microstructure modelling from superimposed ...
Indian Academy of Sciences (India)
The recovered cold rolled microstructure obtained from orientation image microstructure of Al–4%Mg–0.5%Mn alloy (AA5182 alloy) was superimposed on the grid of cellular automata based microstructure model. The Taylor factors of deformed/cold rolled orientations were considered as the driving force for recrystallization.
On Equivalence of Nonequilibrium Thermodynamic and Statistical Entropies
Directory of Open Access Journals (Sweden)
Purushottam D. Gujrati
2015-02-01
Full Text Available We review the concept of nonequilibrium thermodynamic entropy and observables and internal variables as state variables, introduced recently by us, and provide a simple first principle derivation of additive statistical entropy, applicable to all nonequilibrium states by treating thermodynamics as an experimental science. We establish their numerical equivalence in several cases, which includes the most important case when the thermodynamic entropy is a state function. We discuss various interesting aspects of the two entropies and show that the number of microstates in the Boltzmann entropy includes all possible microstates of non-zero probabilities even if the system is trapped in a disjoint component of the microstate space. We show that negative thermodynamic entropy can appear from nonnegative statistical entropy.
Phase transitions, scaling and renormalisation in nonequilibrium systems
Hanney, T E
2002-01-01
critical fixed point. Extensions to include disorder, to higher dimensions, and to other models are all possible using the method. Using the mapping between the Master equation and the Schroedinger equation in imaginary time, this scaling procedure is rephrased as a new blocking for quantum-spin systems. Existing methods of real space renormalisation for quantum-spin systems are applied to a variety of previously unconsidered exclusion models. In particular, it is shown how such techniques can be applied to models whose dynamics conserve particle number. Finally, by applying a Trotter decomposition to the quantum-spin Hamiltonian, it is shown how a nonequilibrium exclusion model can be written in terms of a classical Hamiltonian for Ising spin variables in one higher dimension. This mapping admits the possibility rescaling time and length scales separately, and with reference to a specific update mechanism. Nonequilibrium phase transitions and critical phenomena in simple lattice-based interacting particle mo...
Density-functional method for nonequilibrium electron transport
DEFF Research Database (Denmark)
Brandbyge, Mads; Mozos, J.L.; Ordejon, P.
2002-01-01
We describe an ab initio method for calculating the electronic structure, electronic transport, and forces acting on the atoms, for atomic scale systems connected to semi-infinite electrodes and with an applied voltage bias. Our method is based on the density-functional theory (DFT) as implemented...... in the well tested SIESTA approach (which uses nonlocal norm-conserving pseudopotentials to describe the effect of the core electrons, and linear combination of finite-range numerical atomic orbitals to describe the valence states). We fully deal with the atomistic structure of the whole system, treating both...... the contact and the electrodes on the same footing. The effect of the finite bias (including self-consistency and the solution of the electrostatic problem) is taken into account using nonequilibrium Green's functions. We relate the nonequilibrium Green's function expressions to the more transparent scheme...
Extreme quantum nonequilibrium, nodes, vorticity, drift and relaxation retarding states
Underwood, Nicolas G.
2018-02-01
Consideration is given to the behaviour of de Broglie trajectories that are separated from the bulk of the Born distribution with a view to describing the quantum relaxation properties of more ‘extreme’ forms of quantum nonequilibrium. For the 2D isotropic harmonic oscillator, through the construction of what is termed the ‘drift field’, a description is given of a general mechanism that causes the relaxation of ‘extreme’ quantum nonequilibrium. Quantum states are found which do not feature this mechanism, so that relaxation may be severely delayed or possibly may not take place at all. A method by which these states may be identified, classified and calculated is given in terms of the properties of the nodes of the state. Properties of the nodes that enable this classification are described for the first time.
Non-equilibrium plasma reactor for natrual gas processing
International Nuclear Information System (INIS)
Shair, F.H.; Ravimohan, A.L.
1974-01-01
A non-equilibrium plasma reactor for natural gas processing into ethane and ethylene comprising means of producing a non-equilibrium chemical plasma wherein selective conversion of the methane in natural gas to desired products of ethane and ethylene at a pre-determined ethane/ethylene ratio in the chemical process may be intimately controlled and optimized at a high electrical power efficiency rate by mixing with a recycling gas inert to the chemical process such as argon, helium, or hydrogen, reducing the residence time of the methane in the chemical plasma, selecting the gas pressure in the chemical plasma from a wide range of pressures, and utilizing pulsed electrical discharge producing the chemical plasma. (author)
Construction of a Non-Equilibrium Thermal Boundary Layer Facility
Biles, Drummond; Ebadi, Alireza; Ma, Allen; White, Christopher
2015-11-01
A thermally conductive, electrically heated wall-plate forming the bottom wall of a wind tunnel has been constructed and validation tests have been performed. The wall-plate is a sectioned wall design, where each section is independently heated and controlled. Each section consists of an aluminum 6061 plate, an array of resistive heaters affixed to the bottom of the aluminum plate, and a calcium silicate holder used for thermal isolation. Embedded thermocouples in the aluminum plates are used to monitor the wall temperature and for feedback control of wall heating. The wall-plate is used to investigate thermal transport in both equilibrium and non-equilibrium boundary layers. The non-equilibrium boundary layer flow investigated is oscillatory flow produced by a rotor-stator mechanism placed downstream of the test section of the wind tunnel.
14th International Conference on Nonequilibrium Carrier Dynamics in Semiconductors
Saraniti, M; Nonequilibrium Carrier Dynamics in Semiconductors
2006-01-01
International experts gather every two years at this established conference to discuss recent developments in theory and experiment in non-equilibrium transport phenomena. These developments have been the driving force behind the spectacular advances in semiconductor physics and devices over the last few decades. Originally known as "Hot Carriers in Semiconductors," the 14th conference in the series covered a wide spectrum of traditional topics dealing with non-equilibrium phenomena, ranging from quantum transport to optical phenomena in mesoscopic and nano-scale structures. Particular attention was given this time to emerging areas of this rapidly evolving field, with many sessions covering terahertz devices, high field transport in nitride semiconductors, spintronics, molecular electronics, and bioelectronics applications.
Nonequilibrium Thermodynamics of Ion Flux through Membrane Channels
Directory of Open Access Journals (Sweden)
Chi-Pan Hsieh
2017-01-01
Full Text Available Ion flux through membrane channels is passively driven by the electrochemical potential differences across the cell membrane. Nonequilibrium thermodynamics has been successful in explaining transport mechanisms, including the ion transport phenomenon. However, physiologists may not be familiar with biophysical concepts based on the view of entropy production. In this paper, I have reviewed the physical meanings and connections between nonequilibrium thermodynamics and the expressions commonly used in describing ion fluxes in membrane physiology. The fluctuation theorem can be applied to interpret the flux ratio in the small molecular systems. The multi-ion single-file feature of the ion channel facilitates the utilization of the natural tendency of electrochemical driving force to couple specific biophysical processes and biochemical reactions on the membrane.
Investigation of Non-Equilibrium Radiation for Earth Entry
Brandis, A. M.; Johnston, C. O.; Cruden, B. A.
2016-01-01
For Earth re-entry at velocities between 8 and 11.5 km/s, the accuracy of NASA's computational uid dynamic and radiative simulations of non-equilibrium shock layer radiation is assessed through comparisons with measurements. These measurements were obtained in the NASA Ames Research Center's Electric Arc Shock Tube (EAST) facility. The experiments were aimed at measuring the spatially and spectrally resolved radiance at relevant entry conditions for both an approximate Earth atmosphere (79% N2 : 21% O2 by mole) as well as a more accurate composition featuring the trace species Ar and CO2 (78.08% N2 : 20.95% O2 : 0.04% CO2 : 0.93% Ar by mole). The experiments were configured to target a wide range of conditions, of which shots from 8 to 11.5 km/s at 0.2 Torr (26.7 Pa) are examined in this paper. The non-equilibrium component was chosen to be the focus of this study as it can account for a significant percentage of the emitted radiation for Earth re-entry, and more importantly, non-equilibrium has traditionally been assigned a large uncertainty for vehicle design. The main goals of this study are to present the shock tube data in the form of a non-equilibrium metric, evaluate the level of agreement between the experiment and simulations, identify key discrepancies and to examine critical aspects of modeling non-equilibrium radiating flows. Radiance pro les integrated over discreet wavelength regions, ranging from the Vacuum Ultra Violet (VUV) through to the Near Infra-Red (NIR), were compared in order to maximize both the spectral coverage and the number of experiments that could be used in the analysis. A previously defined non-equilibrium metric has been used to allow comparisons with several shots and reveal trends in the data. Overall, LAURA/HARA is shown to under-predict EAST by as much as 40% and over-predict by as much as 12% depending on the shock speed. DPLR/NEQAIR is shown to under-predict EAST by as much as 50% and over-predict by as much as 20% depending
Non-equilibrium statistical physics with application to disordered systems
Cáceres, Manuel Osvaldo
2017-01-01
This textbook is the result of the enhancement of several courses on non-equilibrium statistics, stochastic processes, stochastic differential equations, anomalous diffusion and disorder. The target audience includes students of physics, mathematics, biology, chemistry, and engineering at undergraduate and graduate level with a grasp of the basic elements of mathematics and physics of the fourth year of a typical undergraduate course. The little-known physical and mathematical concepts are described in sections and specific exercises throughout the text, as well as in appendices. Physical-mathematical motivation is the main driving force for the development of this text. It presents the academic topics of probability theory and stochastic processes as well as new educational aspects in the presentation of non-equilibrium statistical theory and stochastic differential equations.. In particular it discusses the problem of irreversibility in that context and the dynamics of Fokker-Planck. An introduction on fluc...
Supersymmetric electroweak baryogenesis, nonequilibrium field theory and quantum Boltzmann equations
Riotto, Antonio
1998-01-01
The closed time-path (CPT) formalism is a powerful Green's function formulation to describe nonequilibrium phenomena in field theory and it leads to a complete nonequilibrium quantum kinetic theory. In this paper we make use of the CPT formalism to write down a set of quantum Boltzmann equations describing the local number density asymmetries of the particles involved in supersymmetric electroweak baryogenesis. These diffusion equations automatically and self-consistently incorporate the CP-violating sources which fuel baryogenesis when transport properties allow the CP-violating charges to diffuse in front of the bubble wall separating the broken from the unbroken phase at the electroweak phase transition. This is a significant improvement with respect to recent approaches where the CP-violating sources are inserted by hand into the diffusion equations. Furthermore, the CP-violating sources and the particle number changing interactions manifest ``memory'' effects which are typical of the quantum transp ort t...
Analysis of Atomic Electronic Excitation in Nonequilibrium Air Plasmas
International Nuclear Information System (INIS)
He Xin; Jia Hong-Hui; Yin Hong-Wei; Zhang Hai-Liang; Chang Sheng-Li; Yang Jun-Cai; Dang Wei-Hua
2014-01-01
Electronic excitation of atoms is studied in nonequilibrium air plasmas with the electronic temperature between 8000 K and 20000 K. By using the modified Saha—Boltzmann equation, our simplified method takes into account significant radiative processes and strong self-absorption of the vacuum ultraviolet lines. Calculations are carried out at three trajectory points of the Fire II flight experiment. Good agreement with the detailed collisional-radiative model is obtained, and the performance of this method in applications to highly nonequilibrium conditions is better than Park's quasi-steady-state model and Spradian-9.0. A short discussion on the influence of optical thickness of the vacuum ultraviolet radiation is also given. It costs about 2.9 ms on the average to solve one cell of the shock layer on a low cost computer, which shows that the present method is fast and efficient. (physics of gases, plasmas, and electric discharges)
Optimal control of transitions between nonequilibrium steady states.
Directory of Open Access Journals (Sweden)
Patrick R Zulkowski
Full Text Available Biological systems fundamentally exist out of equilibrium in order to preserve organized structures and processes. Many changing cellular conditions can be represented as transitions between nonequilibrium steady states, and organisms have an interest in optimizing such transitions. Using the Hatano-Sasa Y-value, we extend a recently developed geometrical framework for determining optimal protocols so that it can be applied to systems driven from nonequilibrium steady states. We calculate and numerically verify optimal protocols for a colloidal particle dragged through solution by a translating optical trap with two controllable parameters. We offer experimental predictions, specifically that optimal protocols are significantly less costly than naive ones. Optimal protocols similar to these may ultimately point to design principles for biological energy transduction systems and guide the design of artificial molecular machines.
Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry.
van den Bekerom, Dirk; den Harder, Niek; Minea, Teofil; Gatti, Nicola; Linares, Jose Palomares; Bongers, Waldo; van de Sanden, Richard; van Rooij, Gerard
2017-08-01
A flowing microwave plasma based methodology for converting electric energy into internal and/or translational modes of stable molecules with the purpose of efficiently driving non-equilibrium chemistry is discussed. The advantage of a flowing plasma reactor is that continuous chemical processes can be driven with the flexibility of startup times in the seconds timescale. The plasma approach is generically suitable for conversion/activation of stable molecules such as CO2, N2 and CH4. Here the reduction of CO2 to CO is used as a model system: the complementary diagnostics illustrate how a baseline thermodynamic equilibrium conversion can be exceeded by the intrinsic non-equilibrium from high vibrational excitation. Laser (Rayleigh) scattering is used to measure the reactor temperature and Fourier Transform Infrared Spectroscopy (FTIR) to characterize in situ internal (vibrational) excitation as well as the effluent composition to monitor conversion and selectivity.
The dynamics of a thermal non-equilibrium anharmonic oscillator
Nachbagauer, Herbert
1995-01-01
We propose an non-standard method to calculate non-equilibrium physical observables. Considering the generic example of an anharmonic quantum oscillator, we take advantage of the fact that the commutator algebra of second order polynomials in creation/annihilation operators closes. We solve the von~Neumann equation for the density-operator exactly in the mean field approximation and study the time evolution of the particle number and the expectation value .
On nonequilibrium many-body systems III: nonlinear transport theory
International Nuclear Information System (INIS)
Luzzi, R.; Vasconcellos, A.R.; Algarte, A.C.S.
1986-01-01
A nonlinear transport theory for many-body systems arbitrarily away from equilibrium, based on the nonequilibrium statistical operator (NSO) method, is presented. Nonlinear transport equations for a basis set of dynamical quantities are derived using two equivalent treatments that may be considered far reaching generalizations of the Hilbert-Chapman-Enskog method and Mori's generalized Langevin equations method. The first case is considered in some detail and the general characteristics of the theory are discussed. (Author) [pt
Fluctuations and large deviations in non-equilibrium systems
Indian Academy of Sciences (India)
systems. Keywords. Non-equilibrium systems; large deviations; current fluctuations. PACS Nos 02.50.-r; 05.40.-a; 05.70.Ln; 82.20.-w. 1. Introduction. The goal of this .... The model is defined as a one-dimensional lattice of L sites with open bound- .... In [2] a perturbation theory was developed to calculate µ(λ) in powers of λ.
Ward identity for non-equilibrium Fermi systems
Czech Academy of Sciences Publication Activity Database
Velický, B.; Kalvová, Anděla; Špička, Václav
2008-01-01
Roč. 77, č. 4 (2008), 041201/1-041201/4 ISSN 1098-0121 R&D Projects: GA ČR GC202/07/J051 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z10100521 Keywords : non-equilibrium * Green’s functions * quantum transport equations * Ward identity Subject RIV: BE - Theoretical Physics Impact factor: 3.322, year: 2008
Molecular-Based Optical Diagnostics for Hypersonic Nonequilibrium Flows
Danehy, Paul; Bathel, Brett; Johansen, Craig; Winter, Michael; O'Byrne, Sean; Cutler, Andrew
2015-01-01
This presentation package consists of seven different talks rolled up into one. These talks are all invited orals presentations in a special session at the Aviation 2015 conference and represent contributions that were made to a recent AIAA book that will be published entitled 'Hypersonic Nonequilibrium Flows: Fundamentals and Recent Advances'. Slide 5 lists the individual presentations that will be given during the special session.
Mimicking Nonequilibrium Steady States with Time-Periodic Driving
Directory of Open Access Journals (Sweden)
O. Raz
2016-05-01
Full Text Available Under static conditions, a system satisfying detailed balance generically relaxes to an equilibrium state in which there are no currents. To generate persistent currents, either detailed balance must be broken or the system must be driven in a time-dependent manner. A stationary system that violates detailed balance evolves to a nonequilibrium steady state (NESS characterized by fixed currents. Conversely, a system that satisfies instantaneous detailed balance but is driven by the time-periodic variation of external parameters—also known as a stochastic pump (SP—reaches a periodic state with nonvanishing currents. In both cases, these currents are maintained at the cost of entropy production. Are these two paradigmatic scenarios effectively equivalent? For discrete-state systems, we establish a mapping between nonequilibrium stationary states and stochastic pumps. Given a NESS characterized by a particular set of stationary probabilities, currents, and entropy production rates, we show how to construct a SP with exactly the same (time-averaged values. The mapping works in the opposite direction as well. These results establish a proof of principle: They show that stochastic pumps are able to mimic the behavior of nonequilibrium steady states, and vice versa, within the theoretical framework of discrete-state stochastic thermodynamics. Nonequilibrium steady states and stochastic pumps are often used to model, respectively, biomolecular motors driven by chemical reactions and artificial molecular machines steered by the variation of external, macroscopic parameters. Our results loosely suggest that anything a biomolecular machine can do, an artificial molecular machine can do equally well. We illustrate this principle by showing that kinetic proofreading, a NESS mechanism that explains the low error rates in biochemical reactions, can be effectively mimicked by a constrained periodic driving.
Crossover from Nonequilibrium Fractal Growth to Equilibrium Compact Growth
DEFF Research Database (Denmark)
Sørensen, Erik Schwartz; Fogedby, Hans C.; Mouritsen, Ole G.
1988-01-01
Solidification controlled by vacancy diffusion is studied by Monte Carlo simulations of a two-dimensional Ising model defined by a Hamiltonian which models a thermally driven fluid-solid phase transition. The nonequilibrium morphology of the growing solid is studied as a function of time as the s...... as the system relaxes into equilibrium described by a temperature. At low temperatures the model exhibits fractal growth at early times and crossover to compact solidification as equilibrium is approached....
Indian Academy of Sciences (India)
The capabilities of a new microstructure, anode point based, for the detection of gas ionizing radiations are presented. For every single detected ionizing radiation it gives a pair of 'induced' charges (anodic and cathodic) of the same amount (pulses of the same amplitudes), of opposite sign, with the same collection time and ...
Solidification microstructure development
Indian Academy of Sciences (India)
Unknown
Abstract. In the present article, evolution of microstructure during solidi- fication, as a function of various parameters, is discussed. Macrosegregation is described as being due to insufficient diffusivity of solute in the solid. Pattern formation is discussed in the light of instabilities at the solidification growth front. An overview of ...
Dynamic Microstructure Design Consortium
2011-03-23
multiple realizations of polycrystalline microstructure. Cyclic microplasticity in favorably oriented martensite grains is the primary driver for the...can alter the residual stress distribution 13. The present work ex- plores how short-range microplastic deformation during cyclic loading promotes
Non-equilibrium Quasi-Chemical Nucleation Model
Gorbachev, Yuriy E.
2018-04-01
Quasi-chemical model, which is widely used for nucleation description, is revised on the basis of recent results in studying of non-equilibrium effects in reacting gas mixtures (Kolesnichenko and Gorbachev in Appl Math Model 34:3778-3790, 2010; Shock Waves 23:635-648, 2013; Shock Waves 27:333-374, 2017). Non-equilibrium effects in chemical reactions are caused by the chemical reactions themselves and therefore these contributions should be taken into account in the corresponding expressions for reaction rates. Corrections to quasi-equilibrium reaction rates are of two types: (a) spatially homogeneous (caused by physical-chemical processes) and (b) spatially inhomogeneous (caused by gas expansion/compression processes and proportional to the velocity divergency). Both of these processes play an important role during the nucleation and are included into the proposed model. The method developed for solving the generalized Boltzmann equation for chemically reactive gases is applied for solving the set of equations of the revised quasi-chemical model. It is shown that non-equilibrium processes lead to essential deviation of the quasi-stationary distribution and therefore the nucleation rate from its traditional form.
States of Water in Non-Equilibrium Glassy Polymers
Davis, Eric; Elabd, Yossef
2013-03-01
For many applications (e.g., packaging, medical devices) a deeper fundamental understanding of the molecular nature of water in glassy polymer coatings is of significant interest. In this study, the sorption and diffusion of water in two glassy polymers, poly(methyl methacrylate) (PMMA) and poly(styrene) (PS), were measured with both quartz crystal microbalance (QSM) and time-resolved Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy. Non-Fickian diffusion was observed in both PMMA and PS using both experimental techniques due to the non-equilibrium state of the polymers. The specific states of water were observed with FTIR-ATR spectroscopy, where dimers exist in PMMA below a critical concentration and larger clusters were observed above this concentration. Contrastingly, water only exists in PS as larger clusters over the entire sorption isotherm. A correlation between the states of water and the diffusive activation energy of water was observed. Additionally, the pseudo-equilibrium water sorption isotherms in PMMA and PS were accurately predicted with the non-equilibrium statistical associating fluid theory (NE-SAFT). We predict that the combination of time-resolved FTIR-ATR spectroscopy and NE-SAFT can be used on other water-glassy polymer systems to provide a molecular understanding of non-equilibrium sorption and diffusion.
Optimization of some eco-energetic systems
International Nuclear Information System (INIS)
Purica, I.; Pavelescu, M.; Stoica, M.
1976-01-01
An optimization problem of two eco-energetic systems is described. The first one is close to the actual eco-energetic system in Romania, while the second is a new one, based on nuclear energy as primary source and hydrogen energy as secondary source. The optimization problem solved is to find the optimal structure of the systems so that the objective functions adopted, namely unitary energy cost C and total pollution P, to be minimum at the same time. The problem can be modelated with a bimatrix cooperative mathematical game without side payments. We demonstrate the superiority of the new eco-energetic system. (author)
Energetic funnel facilitates facilitated diffusion.
Cencini, Massimo; Pigolotti, Simone
2018-01-25
Transcription factors (TFs) are able to associate to their binding sites on DNA faster than the physical limit posed by diffusion. Such high association rates can be achieved by alternating between three-dimensional diffusion and one-dimensional sliding along the DNA chain, a mechanism-dubbed facilitated diffusion. By studying a collection of TF binding sites of Escherichia coli from the RegulonDB database and of Bacillus subtilis from DBTBS, we reveal a funnel in the binding energy landscape around the target sequences. We show that such a funnel is linked to the presence of gradients of AT in the base composition of the DNA region around the binding sites. An extensive computational study of the stochastic sliding process along the energetic landscapes obtained from the database shows that the funnel can significantly enhance the probability of TFs to find their target sequences when sliding in their proximity. We demonstrate that this enhancement leads to a speed-up of the association process. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Fabrication, microstructure and stress effects in sputtered TiNi thin films
International Nuclear Information System (INIS)
Grummon, D.S.
2000-01-01
Sputtered thin films of equiatomic TiNi and TiNiX ternary alloys have excellent mechanical properties and exhibit robust shape-memory and transformational superelasticity. Furthermore, the energetic nature of the sputter deposition process allows the creation of highly refined microstructures that are difficult to achieve by melt-solidification. The present paper will present recent work on the relationship between processing, microstructure and properties of binary TiNi thin films, focusing primarily on residual stresses, kinetics of stress-relaxation and crystallization, and fine grain sizes achievable using hot-substrate direct crystallization. (orig.)
Generalization of the second law for a transition between nonequilibrium states
Energy Technology Data Exchange (ETDEWEB)
Takara, K. [Department of Mathematical Sciences, Ibaraki University, Bunkyo, Mito 310-8512 (Japan); Hasegawa, H.-H., E-mail: hhh@mx.ibaraki.ac.j [Department of Mathematical Sciences, Ibaraki University, Bunkyo, Mito 310-8512 (Japan); Center for Complex Quantum Systems, Univ. of Texas, Austin, TX 78712 (United States); Driebe, D.J. [Embry-Riddle Aeronautical University Worldwide, Fort Lauderdale, FL 33309 (United States)
2010-12-01
The maximum work formulation of the second law of thermodynamics is generalized for a transition between nonequilibrium states. The relative entropy, the Kullback-Leibler divergence between the nonequilibrium states and the canonical distribution, determines the maximum ability to work. The difference between the final and the initial relative entropies with an effective temperature gives the maximum dissipative work for both adiabatic and isothermal processes. Our formulation reduces to both the Vaikuntanathan-Jarzynski relation and the nonequilibrium Clausius relation in certain situations. By applying our formulation to a heat engine the Carnot cycle is generalized to a circulation among nonequilibrium states.
Aquilanti, Vincenzo; Coutinho, Nayara Dantas; Carvalho-Silva, Valter Henrique
2017-03-01
This article surveys the empirical information which originated both by laboratory experiments and by computational simulations, and expands previous understanding of the rates of chemical processes in the low-temperature range, where deviations from linearity of Arrhenius plots were revealed. The phenomenological two-parameter Arrhenius equation requires improvement for applications where interpolation or extrapolations are demanded in various areas of modern science. Based on Tolman's theorem, the dependence of the reciprocal of the apparent activation energy as a function of reciprocal absolute temperature permits the introduction of a deviation parameter d covering uniformly a variety of rate processes, from those where quantum mechanical tunnelling is significant and d 0, corresponding to the Pareto-Tsallis statistical weights: these generalize the Boltzmann-Gibbs weight, which is recovered for d = 0. It is shown here how the weights arise, relaxing the thermodynamic equilibrium limit, either for a binomial distribution if d > 0 or for a negative binomial distribution if d < 0, formally corresponding to Fermion-like or Boson-like statistics, respectively. The current status of the phenomenology is illustrated emphasizing case studies; specifically (i) the super-Arrhenius kinetics, where transport phenomena accelerate processes as the temperature increases; (ii) the sub-Arrhenius kinetics, where quantum mechanical tunnelling propitiates low-temperature reactivity; (iii) the anti-Arrhenius kinetics, where processes with no energetic obstacles are rate-limited by molecular reorientation requirements. Particular attention is given for case (i) to the treatment of diffusion and viscosity, for case (ii) to formulation of a transition rate theory for chemical kinetics including quantum mechanical tunnelling, and for case (iii) to the stereodirectional specificity of the dynamics of reactions strongly hindered by the increase of temperature. This article is part of
Hydro energetic inventory study from Chapecozinho river
International Nuclear Information System (INIS)
Pimenta, S.C.; Sureck, M.A.A.; Nascimento, P.R.; Kawasaki, M.; Silva Felipe, R. da.
1990-01-01
The Hydro energetic Inventory Study in Chapecozinho River Basin, Brazil is described, comparing the proposed results in 1979 with the actual review in 1989. An analysis for solution the socio-economic and environment problems is also presented. (author)
Global Positioning System (GPS) Energetic Particle Data
National Oceanic and Atmospheric Administration, Department of Commerce — Energetic particle data from the CXD and BDD instrument on the GPS constellation are available to the space weather research community. The release of these data...
Energetic particle observations at the subsolar magnetopause
Directory of Open Access Journals (Sweden)
A. A. Eccles
2002-04-01
Full Text Available The pitch-angle distributions (PAD of energetic particles are examined as the ISEE-1 satellite crosses the Earth’s magnetopause near the subsolar point. The investigation focuses on the possible existence of a particular type of distribution that would be associated with a source of energetic particles in the high-latitude magnetosphere. PADs, demonstrating broad, persistent field-aligned fluxes filling a single hemisphere (upper/northern or lower/southern, were observed just sunward of the magnetopause current layer for an extended period of many minutes. These distributions are a direct prediction of a possible source of energetic particles located in the high altitude dayside cusp and we present five examples in detail of the three-dimensional particle distributions to demonstrate their existence. From these results, other possible causes of such PADs are examined.Key words. Magnetospheric physics (energetic particles, precipitating; magnetopause, cusp and boundary layers; magnetospheric configuration and dynamics
Organization of the national energetic institutions
International Nuclear Information System (INIS)
Waltenberg, D.A.M.
1983-01-01
This text broaches, in a critical pourt of view, the organization of national energetic institutions, the need of a law revision, the problem of the rising of tariff and shows the decisions of GC01 [pt
Modeling Thermal Ignition of Energetic Materials
National Research Council Canada - National Science Library
Gerri, Norman J; Berning, Ellen
2004-01-01
This report documents an attempt to computationally simulate the mechanics and thermal regimes created when a threat perforates an armor envelope and comes in contact with stowed energetic material...
Identification of microstructures
International Nuclear Information System (INIS)
Padilha, A.F.; Ambrozio Filho, F.
1984-01-01
The identification of phases in a material can require the utilization of several techniques. The most used technique and discussed are: optical microscope, scanning electron microscope, transmission electron microscope, X-ray diffraction and 'in-situ' chemical analysis of the phases. The microstructures were classified, in according to the size and phase volumetric fraction, in four types. For each type the most appropriate techniques for identifying the phases are discussed. (E.G.) [pt
Indian Academy of Sciences (India)
The complete lack of insulating materials in the active volume of this microstructure avoids problems of charging-up and makes stable and repeatable its behavior. It is possible to observe primary avalanches with a size of more than 2.5 × 107 electrons (4 pC), which give current pulses with a peak of more than 0.26 mA on ...
Safer energetic materials by a nanotechnological approach
Siegert, Benny; Comet, Marc; Spitzer, Denis
2011-09-01
Energetic materials - explosives, thermites, populsive powders - are used in a variety of military and civilian applications. Their mechanical and electrostatic sensitivity is high in many cases, which can lead to accidents during handling and transport. These considerations limit the practical use of some energetic materials despite their good performance. For industrial applications, safety is one of the main criteria for selecting energetic materials. The sensitivity has been regarded as an intrinsic property of a substance for a long time. However, in recent years, several approaches to lower the sensitivity of a given substance, using nanotechnology and materials engineering, have been described. This feature article gives an overview over ways to prepare energetic (nano-)materials with a lower sensitivity.Energetic materials - explosives, thermites, populsive powders - are used in a variety of military and civilian applications. Their mechanical and electrostatic sensitivity is high in many cases, which can lead to accidents during handling and transport. These considerations limit the practical use of some energetic materials despite their good performance. For industrial applications, safety is one of the main criteria for selecting energetic materials. The sensitivity has been regarded as an intrinsic property of a substance for a long time. However, in recent years, several approaches to lower the sensitivity of a given substance, using nanotechnology and materials engineering, have been described. This feature article gives an overview over ways to prepare energetic (nano-)materials with a lower sensitivity. Electronic supplementary information (ESI) available: Experimental details for the preparation of the V2O5@CNF/Al nanothermite; X-ray diffractogram of the V2O5@CNF/Al combustion residue; installation instructions and source code for the nt-timeline program. See DOI: 10.1039/c1nr10292c
Energetic Optimal Control Of Adjustable Drive Systems
Directory of Open Access Journals (Sweden)
Ion BIVOL
2002-12-01
Full Text Available n the paper is developed a new control strategy for the adjustable speed drives. The strategy consists in the energetic optimal control of the dynamic regimes as starting, stopping and reversing. The main developed problems: formulation of energetic optimal problem, solution, experimental results via simulation and some considerations concerning the use of the control. The optimal developed solution can be applied for the both AC and DC drives, but only for linear systems.
Structure of Energetic Particle Mediated Shocks Revisited
Energy Technology Data Exchange (ETDEWEB)
Mostafavi, P.; Zank, G. P. [Department of Space Science, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Webb, G. M. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States)
2017-05-20
The structure of collisionless shock waves is often modified by the presence of energetic particles that are not equilibrated with the thermal plasma (such as pickup ions [PUIs] and solar energetic particles [SEPs]). This is relevant to the inner and outer heliosphere and the Very Local Interstellar Medium (VLISM), where observations of shock waves (e.g., in the inner heliosphere) show that both the magnetic field and thermal gas pressure are less than the energetic particle component pressures. Voyager 2 observations revealed that the heliospheric termination shock (HTS) is very broad and mediated by energetic particles. PUIs and SEPs contribute both a collisionless heat flux and a higher-order viscosity. We show that the incorporation of both effects can completely determine the structure of collisionless shocks mediated by energetic ions. Since the reduced form of the PUI-mediated plasma model is structurally identical to the classical cosmic ray two-fluid model, we note that the presence of viscosity, at least formally, eliminates the need for a gas sub-shock in the classical two-fluid model, including in that regime where three are possible. By considering parameters upstream of the HTS, we show that the thermal gas remains relatively cold and the shock is mediated by PUIs. We determine the structure of the weak interstellar shock observed by Voyager 1 . We consider the inclusion of the thermal heat flux and viscosity to address the most general form of an energetic particle-thermal plasma two-fluid model.
Structure of Energetic Particle Mediated Shocks Revisited
Mostafavi, P.; Zank, G. P.; Webb, G. M.
2017-05-01
The structure of collisionless shock waves is often modified by the presence of energetic particles that are not equilibrated with the thermal plasma (such as pickup ions [PUIs] and solar energetic particles [SEPs]). This is relevant to the inner and outer heliosphere and the Very Local Interstellar Medium (VLISM), where observations of shock waves (e.g., in the inner heliosphere) show that both the magnetic field and thermal gas pressure are less than the energetic particle component pressures. Voyager 2 observations revealed that the heliospheric termination shock (HTS) is very broad and mediated by energetic particles. PUIs and SEPs contribute both a collisionless heat flux and a higher-order viscosity. We show that the incorporation of both effects can completely determine the structure of collisionless shocks mediated by energetic ions. Since the reduced form of the PUI-mediated plasma model is structurally identical to the classical cosmic ray two-fluid model, we note that the presence of viscosity, at least formally, eliminates the need for a gas sub-shock in the classical two-fluid model, including in that regime where three are possible. By considering parameters upstream of the HTS, we show that the thermal gas remains relatively cold and the shock is mediated by PUIs. We determine the structure of the weak interstellar shock observed by Voyager 1. We consider the inclusion of the thermal heat flux and viscosity to address the most general form of an energetic particle-thermal plasma two-fluid model.
International Nuclear Information System (INIS)
Snezhko, Alexey
2011-01-01
Colloidal dispersions of interacting particles subjected to an external periodic forcing often develop nontrivial self-assembled patterns and complex collective behavior. A fundamental issue is how collective ordering in such non-equilibrium systems arises from the dynamics of discrete interacting components. In addition, from a practical viewpoint, by working in regimes far from equilibrium new self-organized structures which are generally not available through equilibrium thermodynamics can be created. In this review spontaneous self-assembly phenomena in magnetic colloidal dispersions suspended at liquid-air interfaces and driven out of equilibrium by an alternating magnetic field are presented. Experiments reveal a new type of nontrivially ordered self-assembled structures emerging in such systems in a certain range of excitation parameters. These dynamic structures emerge as a result of the competition between magnetic and hydrodynamic forces and have complex unconventional magnetic ordering. Nontrivial self-induced hydrodynamic fields accompany each out-of-equilibrium pattern. Spontaneous symmetry breaking of the self-induced surface flows leading to a formation of self-propelled microstructures has been discovered. Some features of the self-localized structures can be understood in the framework of the amplitude equation (Ginzburg-Landau type equation) for parametric waves coupled to the conservation law equation describing the evolution of the magnetic particle density and the Navier-Stokes equation for hydrodynamic flows. To understand the fundamental microscopic mechanisms governing self-assembly processes in magnetic colloidal dispersions at liquid-air interfaces a first-principle model for a non-equilibrium self-assembly is presented. The latter model allows us to capture in detail the entire process of out-of-equilibrium self-assembly in the system and reproduces most of the observed phenomenology. (topical review)
Numerical modeling of an alloy droplet deposition with non-equilibrium solidification
Ramanuj, Vimal
taking place in rapidly solidifying domains. Solid phase diffusion theories proposed in the literature are incorporated in the solute conservation equation through a back diffusion parameter till the eutectic composition; beyond which a special treatment is proposed. A simplified homogeneous mushy region model has also been outline. Both models are employed to reproduce analytical results under limiting conditions and also experimentally verified. The primary objective of the present work is to examine the splat morphology, solidification behavior and microstructural characteristics under varying operational parameters. A simplified homogeneous mushy region model is first applied to study the role of convection in an SS304 droplet deposition with substrate remelting. The results are compared with experimental findings reported in the literature and a good agreement is observed. Furthermore, a hypoeutectic Sn-Pb alloy droplet deposition is studied using a comprehensive coupled temperature solute model that accounts for the non-equilibrium solidification occurring in eutectic type of alloys. Particular focus is laid on the limitations of a homogeneous mushy region assumption, role of species composition in governing solidification, estimation of the microstructural properties and eutectic formation.
Properties and Microstructure of Laser Welded VM12-SHC Steel Pipes Joints
Skrzypczyk A.; Danielewski H.
2016-01-01
Paper presents results of microstructure and tests of welded joints of new generation VM12-SHC martensitic steel using high power CO2 laser (LBW method) with bifocal welding head. VM12-SHC is dedicated to energetic installation material, designed to replace currently used. High content of chromium and others alloying elements improve its resistance and strength characteristic. Use of VM12-SHC steel for production of the superheaters, heating chambers and walls in steam boilers resulted in var...
On the Nonequilibrium Interface Kinetics of Rapid Coupled Eutectic Growth
Dong, H.; Chen, Y. Z.; Shan, G. B.; Zhang, Z. R.; Liu, F.
2017-08-01
Nonequilibrium interface kinetics (NEIK) is expected to play an important role in coupled growth of eutectic alloys, when solidification velocity is high and intermetallic compound or topologically complex phases form in the crystallized product. In order to quantitatively evaluate the effect of NEIK on the rapid coupled eutectic growth, in this work, two nonequilibrium interface kinetic effects, i.e., atom attachment and solute trapping at the solid-liquid interface, were incorporated into the analyses of the coupled eutectic growth under the rapid solidification condition. First, a coupled growth model incorporating the preceding two nonequilibrium kinetic effects was derived. On this basis, an expression of kinetic undercooling (Δ T k), which is used to characterize the NEIK, was defined. The calculations based on the as-derived couple growth model show good agreement with the reported experimental results achieved in rapidly solidified eutectic Al-Sm alloys consisting of a solid solution phase ( α-Al) and an intermetallic compound phase (Al11Sm3). In terms of the definition of Δ T k defined in this work, the role of NEIK in the coupled growth of the Al-Sm eutectic system was analyzed. The results show that with increasing the coupled growth velocity, Δ T k increases continuously, and its ratio to the total undercooling reaches 0.32 at the maximum growth velocity for coupled eutectic growth. Parametric analyses on two key alloy parameters that influence Δ T k, i.e., interface kinetic parameter ( μ i ) and solute distribution coefficient ( k e ), indicate that both μ i and k e influence the NEIK significantly and the decrease of either these two parameters enhances the NEIK effect.
Extended irreversible thermodynamics and non-equilibrium temperature
Directory of Open Access Journals (Sweden)
Casas-Vazquez, Jose'
2008-02-01
Full Text Available We briefly review the concept of non-equilibrium temperature from the perspectives of extended irreversible thermodynamics, fluctuation theory, and statistical mechanics. The relations between different proposals are explicitly examined in two especially simple systems: an ideal gas in steady shear flow and a forced harmonic oscillator in a thermal bath. We examine with special detail temperatures related to the average molecular kinetic energy along different spatial directions, to the average configurational energy, to the derivative of the entropy with respect to internal energy, to fluctuation-dissipation relation and discuss their measurement.
The non-equilibrium nature of culinary evolution
Kinouchi, Osame; Diez-Garcia, Rosa W.; Holanda, Adriano J.; Zambianchi, Pedro; Roque, Antonio C.
2008-07-01
Food is an essential part of civilization, with a scope that ranges from the biological to the economic and cultural levels. Here, we study the statistics of ingredients and recipes taken from Brazilian, British, French and Medieval cookery books. We find universal distributions with scale invariant behaviour. We propose a copy-mutate process to model culinary evolution that fits our empirical data very well. We find a cultural 'founder effect' produced by the non-equilibrium dynamics of the model. Both the invariant and idiosyncratic aspects of culture are accounted for by our model, which may have applications in other kinds of evolutionary processes.
Structural characterization of lipidic systems under nonequilibrium conditions
DEFF Research Database (Denmark)
Yaghmur, Anan; Rappolt, Michael
2012-01-01
manipulation techniques including, for instance, stop-flow mixing or rapid temperature-jump perturbation is given. Second, our recent synchrotron SAXS findings on the dynamic structural response of gold nanoparticle-loaded vesicles upon exposure to an ultraviolet light source, the impact of rapidly mixing...... and the possible formation of intermediate states in the millisecond to second range. The need for investigating self-assembled systems, mainly stimuli-responsive drug nanocarriers, under nonequilibrium conditions is discussed. For pharmaceutically relevant applications, it is essential to combine...
Cumulants in perturbation expansions for non-equilibrium field theory
International Nuclear Information System (INIS)
Fauser, R.
1995-11-01
The formulation of perturbation expansions for a quantum field theory of strongly interacting systems in a general non-equilibrium state is discussed. Non-vanishing initial correlations are included in the formulation of the perturbation expansion in terms of cumulants. The cumulants are shown to be the suitable candidate for summing up the perturbation expansion. Also a linked-cluster theorem for the perturbation series with cumulants is presented. Finally a generating functional of the perturbation series with initial correlations is studied. We apply the methods to a simple model of a fermion-boson system. (orig.)
Nonequilibrium effects on shock-layer radiometry during earth entry.
Arnold, J. O.; Whiting, E. E.
1973-01-01
Radiative enhancement factors for the CN violet and N2(+) first negative band systems caused by nonequilibrium thermochemistry in the shock layer of a blunt-nosed vehicle during earth entry are reported. The results are based on radiometric measurements obtained with the aid of a combustion-driven shock tube. The technique of converting the shock-tube measurements into predictions of the enhancement factors for the blunt-body case is described, showing it to be useful for similar applications of other shock-tube measurements.
Effects of vacancies on overshooting in nonequilibrium ordering processes
DEFF Research Database (Denmark)
Gilhøj, Henriette; Jeppesen, Claus; Mouritsen, Ole G.
1996-01-01
The effects of annealed site dilution on the nonequilibrium ordering process in the two-dimensional Ising model with a nonconserved order parameter have been studied using Monte Carlo simulation. It is found that the transient development of a local order that is larger than the equilibrium order...... (overshooting), as recently reported in the pure Ising model [H. Gilhoj, C. Jeppesen, and O. G; Mouritsen, Phys. Rev. Lett. 75, 3305 (1995)], persists in the dilute model and is accompanied by a depletion of the vacancies within the ordered domains....
Non-exponential dynamic relaxation in strongly nonequilibrium nonideal plasmas
International Nuclear Information System (INIS)
Morozov, I V; Norman, G E
2003-01-01
Relaxation of kinetic energy to the equilibrium state is simulated by the molecular dynamics method for nonideal two-component non-degenerate plasmas. Three limiting examples of initial states of strongly nonequilibrium plasma are considered: zero electron velocities, zero ion velocities and zero velocities of both electrons and ions. The initial non-exponential stage, its duration τ nB and subsequent exponential stages of the relaxation process are studied for a wide range of the nonideality parameter and the ion mass
Computation of current cumulants for small nonequilibrium systems
Czech Academy of Sciences Publication Activity Database
Baiesi, M.; Maes, C.; Netočný, Karel
2009-01-01
Roč. 135, č. 1 (2009), s. 57-75 ISSN 0022-4715 R&D Projects: GA ČR GC202/07/J051 Institutional research plan: CEZ:AV0Z10100520 Keywords : fluctuations * nonequilibrium * cumulant expansion Subject RIV: BE - Theoretical Physics Impact factor: 1.390, year: 2009 http://www.springerlink.com/content/a632834h10008034/?p=a341f2e536d34c989ac8e057ea4f72a7π=2
Non-equilibrium steady state in the hydro regime
Energy Technology Data Exchange (ETDEWEB)
Pourhasan, Razieh [Science Institute, University of Iceland,Dunhaga 5, 107 Reykjavik (Iceland)
2016-02-01
We study the existence and properties of the non-equilibrium steady state which arises by putting two copies of systems at different temperatures into a thermal contact. We solve the problem for the relativistic systems that are described by the energy-momentum of a perfect hydro with general equation of state (EOS). In particular, we examine several simple examples: a hydro with a linear EOS, a holographic CFT perturbed by a relevant operator and a barotropic fluid, i.e., P=P(E). Our studies suggest that the formation of steady state is a universal result of the hydro regime regardless of the kind of fluid.
A nonequilibrium renormalization group approach to turbulent reheating
International Nuclear Information System (INIS)
Zanella, Juan; Calzetta, Esteban
2007-01-01
We use nonequilibrium renormalization group (RG) techniques to analyse the thermalization process in quantum field theory, and, by extension, reheating after inflation. Even if at a high scale Λ the theory is described by a non-dissipative λψ 4 theory, and the RG running induces nontrivial noise and dissipation. For long wavelength and slowly varying field configurations, the noise and dissipation are white and ohmic, respectively. The theory will then tend to thermalize to an effective temperature given by the fluctuation-dissipation theorem
Memory effects and virial corrections in nonequilibrium dense nuclear matter
International Nuclear Information System (INIS)
Morawetz, K.; Roepke, G.
1995-01-01
The aim of the present paper is to close the gap between a kinetic approach including memory and the description of correlated states. It is shown that the first order retardation effects in the kinetic equation leads to the same expression for the correlated density or energy in equilibrium, which is known from the quantum Beth-Uhlenbeck approach. We link the approaches of equilibrium to the kinetic level of description and generalize it by this way to nonequilibrium situations found in finite systems. (orig.)
External non-white noise and nonequilibrium phase transitions
International Nuclear Information System (INIS)
Sancho, J.M.; San Miguel, M.
1980-01-01
Langevin equations with external non-white noise are considered. A Fokker Planck equation valid in general in first order of the correlation time tau of the noise is derived. In some cases its validity can be extended to any value of tau. The effect of a finite tau in the nonequilibrium phase transitions induced by the noise is analyzed, by means of such Fokker Planck equation, in general, for the Verhulst equation under two different kind of fluctuations, and for a genetic model. It is shown that new transitions can appear and that the threshold value of the parameter can be changed. (orig.)
Shape characteristics of equilibrium and non-equilibrium fractal clusters.
Mansfield, Marc L; Douglas, Jack F
2013-07-28
It is often difficult in practice to discriminate between equilibrium and non-equilibrium nanoparticle or colloidal-particle clusters that form through aggregation in gas or solution phases. Scattering studies often permit the determination of an apparent fractal dimension, but both equilibrium and non-equilibrium clusters in three dimensions frequently have fractal dimensions near 2, so that it is often not possible to discriminate on the basis of this geometrical property. A survey of the anisotropy of a wide variety of polymeric structures (linear and ring random and self-avoiding random walks, percolation clusters, lattice animals, diffusion-limited aggregates, and Eden clusters) based on the principal components of both the radius of gyration and electric polarizability tensor indicates, perhaps counter-intuitively, that self-similar equilibrium clusters tend to be intrinsically anisotropic at all sizes, while non-equilibrium processes such as diffusion-limited aggregation or Eden growth tend to be isotropic in the large-mass limit, providing a potential means of discriminating these clusters experimentally if anisotropy could be determined along with the fractal dimension. Equilibrium polymer structures, such as flexible polymer chains, are normally self-similar due to the existence of only a single relevant length scale, and are thus anisotropic at all length scales, while non-equilibrium polymer structures that grow irreversibly in time eventually become isotropic if there is no difference in the average growth rates in different directions. There is apparently no proof of these general trends and little theoretical insight into what controls the universal anisotropy in equilibrium polymer structures of various kinds. This is an obvious topic of theoretical investigation, as well as a matter of practical interest. To address this general problem, we consider two experimentally accessible ratios, one between the hydrodynamic and gyration radii, the other
Nonequilibrium thermodynamics and energy efficiency in weight loss diets
Directory of Open Access Journals (Sweden)
Fine Eugene J
2007-07-01
Full Text Available Abstract Carbohydrate restriction as a strategy for control of obesity is based on two effects: a behavioral effect, spontaneous reduction in caloric intake and a metabolic effect, an apparent reduction in energy efficiency, greater weight loss per calorie consumed. Variable energy efficiency is established in many contexts (hormonal imbalance, weight regain and knock-out experiments in animal models, but in the area of the effect of macronutrient composition on weight loss, controversy remains. Resistance to the idea comes from a perception that variable weight loss on isocaloric diets would somehow violate the laws of thermodynamics, that is, only caloric intake is important ("a calorie is a calorie". Previous explanations of how the phenomenon occurs, based on equilibrium thermodynamics, emphasized the inefficiencies introduced by substrate cycling and requirements for increased gluconeogenesis. Living systems, however, are maintained far from equilibrium, and metabolism is controlled by the regulation of the rates of enzymatic reactions. The principles of nonequilibrium thermodynamics which emphasize kinetic fluxes as well as thermodynamic forces should therefore also be considered. Here we review the principles of nonequilibrium thermodynamics and provide an approach to the problem of maintenance and change in body mass by recasting the problem of TAG accumulation and breakdown in the adipocyte in the language of nonequilibrium thermodynamics. We describe adipocyte physiology in terms of cycling between an efficient storage mode and a dissipative mode. Experimentally, this is measured in the rate of fatty acid flux and fatty acid oxidation. Hormonal levels controlled by changes in dietary carbohydrate regulate the relative contributions of the efficient and dissipative parts of the cycle. While no experiment exists that measures all relevant variables, the model is supported by evidence in the literature that 1 dietary carbohydrate, via its
Nonequilibrium Microscopic Distribution of Thermal Current in Particle Systems
Yukawa, Satoshi
2009-02-15
A nonequilibrium distribution function of microscopic thermal current is studied by a direct numerical simulation in a thermal conducting steady state of particle systems. Two characteristic temperatures of the thermal current are investigated on the basis of the distribution. It is confirmed that the temperature depends on the current direction; Parallel temperature to the heat-flux is higher than antiparallel one. The difference between the parallel temperature and the antiparallel one is proportional to a macroscopic temperature gradient. ©2009 The Physical Society of Japan.
Nonequilibrium statistical mechanics and stochastic thermodynamics of small systems
International Nuclear Information System (INIS)
Tu Zhanchun
2014-01-01
Thermodynamics is an old subject. The research objects in conventional thermodynamics are macroscopic systems with huge number of particles. In recent 30 years, thermodynamics of small systems is a frontier topic in physics. Here we introduce nonequilibrium statistical mechanics and stochastic thermodynamics of small systems. As a case study, we construct a Canot-like cycle of a stochastic heat engine with a single particle controlled by a time-dependent harmonic potential. We find that the efficiency at maximum power is 1 - √T c /T h , where Tc and Th are the temperatures of cold bath and hot bath, respectively. (author)
Equilibrium and nonequilibrium solvation and solute electronic structure
International Nuclear Information System (INIS)
Kim, H.J.; Hynes, J.T.
1990-01-01
When a molecular solute is immersed in a polar and polarizable solvent, the electronic wave function of the solute system is altered compared to its vacuum value; the solute electronic structure is thus solvent-dependent. Further, the wave function will be altered depending upon whether the polarization of the solvent is or is not in equilibrium with the solute charge distribution. More precisely, while the solvent electronic polarization should be in equilibrium with the solute electronic wave function, the much more sluggish solvent orientational polarization need not be. We call this last situation non-equilibrium solvation. We outline a nonlinear Schroedinger equation approach to these issues
Liu, Yu; Huang, Yuanchun; Xiao, Zhengbing
2017-11-01
The effect of ultrasonic casting on microstructure and its genetic effects on strength, exfoliating corrosion, stress corrosion and electrochemical behavior of 7085 aluminum alloy have been investigated by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM), together with tensile testing, exfoliation corrosion testing, electrical conductivity testing and polarization curve. The results indicate that ultrasonic casting could refine the grain, alleviate segregation and inhibit the formation of coarse nonequilibrium phase in as-cast state; in addition, the dissolution of nonequilibrium phase in the ultrasonic ingot during homogenization turns out to be more thorough. What is more, the plate processed from ultrasonic ingot holds a lower ratio of recrystallization after solid solution, and the corrosion performance of the alloy was improved under T6 temper, without sacrifice of strength, owing to the dispersive distribution of strengthening phase in the matrix and the coarse, sparse GBPs.
A new algorithm for extended nonequilibrium molecular dynamics simulations of mixed flow
Hunt, T.A.; Hunt, Thomas A.; Bernardi, Stefano; Todd, B.D.
2010-01-01
In this work, we develop a new algorithm for nonequilibrium molecular dynamics of fluids under planar mixed flow, a linear combination of planar elongational flow and planar Couette flow. To date, the only way of simulating mixed flow using nonequilibrium molecular dynamics techniques was to impose
On the definition of equilibrium and non-equilibrium states in dynamical systems
Akimoto, Takuma
2008-01-01
We propose a definition of equilibrium and non-equilibrium states in dynamical systems on the basis of the time average. We show numerically that there exists a non-equilibrium non-stationary state in the coupled modified Bernoulli map lattice.
Optics of dielectric microstructures
DEFF Research Database (Denmark)
Søndergaard, Thomas
2002-01-01
and photonic crystal microcavity. In chapter 4 a general theory based on a Green's tensor formalism is put forward for spontaneous emission in active dielectric microstructures, and an example is given whre the method is applied to a fiber amplifier. The Green's tensor in chapter 4 is constructed a a summation...... over a biorthogonal set of electromagnetic modes. An alternative method based on a Lippmann-Schwinger type integral equation is presented in chapter 5 for the construction of the Green's tensor and calculation of emission of radiation by sources. The integral equation approach is applied to calculate...
VLSI electronics microstructure science
1981-01-01
VLSI Electronics: Microstructure Science, Volume 3 evaluates trends for the future of very large scale integration (VLSI) electronics and the scientific base that supports its development.This book discusses the impact of VLSI on computer architectures; VLSI design and design aid requirements; and design, fabrication, and performance of CCD imagers. The approaches, potential, and progress of ultra-high-speed GaAs VLSI; computer modeling of MOSFETs; and numerical physics of micron-length and submicron-length semiconductor devices are also elaborated. This text likewise covers the optical linewi
VLSI electronics microstructure science
1982-01-01
VLSI Electronics: Microstructure Science, Volume 4 reviews trends for the future of very large scale integration (VLSI) electronics and the scientific base that supports its development.This book discusses the silicon-on-insulator for VLSI and VHSIC, X-ray lithography, and transient response of electron transport in GaAs using the Monte Carlo method. The technology and manufacturing of high-density magnetic-bubble memories, metallic superlattices, challenge of education for VLSI, and impact of VLSI on medical signal processing are also elaborated. This text likewise covers the impact of VLSI t
Non-equilibrium theory of arrested spinodal decomposition
Energy Technology Data Exchange (ETDEWEB)
Olais-Govea, José Manuel; López-Flores, Leticia; Medina-Noyola, Magdaleno [Instituto de Física “Manuel Sandoval Vallarta,” Universidad Autónoma de San Luis Potosí, Álvaro Obregón 64, 78000 San Luis Potosí, SLP (Mexico)
2015-11-07
The non-equilibrium self-consistent generalized Langevin equation theory of irreversible relaxation [P. E. Ramŕez-González and M. Medina-Noyola, Phys. Rev. E 82, 061503 (2010); 82, 061504 (2010)] is applied to the description of the non-equilibrium processes involved in the spinodal decomposition of suddenly and deeply quenched simple liquids. For model liquids with hard-sphere plus attractive (Yukawa or square well) pair potential, the theory predicts that the spinodal curve, besides being the threshold of the thermodynamic stability of homogeneous states, is also the borderline between the regions of ergodic and non-ergodic homogeneous states. It also predicts that the high-density liquid-glass transition line, whose high-temperature limit corresponds to the well-known hard-sphere glass transition, at lower temperature intersects the spinodal curve and continues inside the spinodal region as a glass-glass transition line. Within the region bounded from below by this low-temperature glass-glass transition and from above by the spinodal dynamic arrest line, we can recognize two distinct domains with qualitatively different temperature dependence of various physical properties. We interpret these two domains as corresponding to full gas-liquid phase separation conditions and to the formation of physical gels by arrested spinodal decomposition. The resulting theoretical scenario is consistent with the corresponding experimental observations in a specific colloidal model system.
Application of non-equilibrium plasmas in medicine
Directory of Open Access Journals (Sweden)
Mojsilović S.
2012-01-01
Full Text Available We review the potential of plasma medical applications, the connections to nanotechnologies and the results obtained by our group. A special issue in plasma medicine is the development of the plasma sources that would achieve non-equilibrium at atmospheric pressure in atmospheric gas mixture with no or only marginal heating of the gas, and with desired properties and mechanisms that may be controlled. Our studies have shown that control of radicals or chemically active products of the discharge such as ROS (reactive oxygen species and/or NO may be used to control the growth of the seeds. At the same time specially designed plasma needle and other sources were shown to be efficient to sterilize not only colonies of bacteria but also planctonic samples (microorganisms protected by water or bio films. Finally we have shown that plasma may induce differentiation of stem cells. Non-equilibrium plasmas may be used in detection of different specific markers in medicine. For example proton transfer mass spectroscopy may be employed in detection of volatile organic compounds without their dissociation and thus as a technique for instantaneous measurement of the presence of markers for numerous diseases. [Projekat Ministarstva nauke Republike Srbije, br. ON171037 i br. III41011
Nonequilibrium transport in the pseudospin-1 Dirac-Weyl system
Wang, Cheng-Zhen; Xu, Hong-Ya; Huang, Liang; Lai, Ying-Cheng
2017-09-01
Recently, solid state materials hosting pseudospin-1 quasiparticles have attracted a great deal of attention. In these materials, the energy band contains a pair of Dirac cones and a flatband through the connecting point of the cones. As the "caging" of carriers with a zero group velocity, the flatband itself has zero conductivity. However, in a nonequilibrium situation where a constant electric field is suddenly switched on, the flatband can enhance the resulting current in both the linear and nonlinear response regimes through distinct physical mechanisms. Using the (2 +1 )-dimensional pseudospin-1 Dirac-Weyl system as a concrete setting, we demonstrate that, in the weak field regime, the interband current is about twice larger than that for pseudospin-1/2 system due to the interplay between the flatband and the negative band, with the scaling behavior determined by the Kubo formula. In the strong field regime, the intraband current is √{2 } times larger than that in the pseudospin-1/2 system, due to the additional contribution from particles residing in the flatband. In this case, the current and field follow the scaling law associated with Landau-Zener tunneling. These results provide a better understanding of the role of the flatband in nonequilibrium transport and are experimentally testable using electronic or photonic systems.
Nozzle Flow with Vibrational Nonequilibrium. Ph.D. Thesis
Landry, John Gary
1995-01-01
Flow of nitrogen gas through a converging-diverging nozzle is simulated. The flow is modeled using the Navier-Stokes equations that have been modified for vibrational nonequilibrium. The energy equation is replaced by two equations. One equation accounts for energy effects due to the translational and rotational degrees of freedom, and the other accounts for the affects due to the vibrational degree of freedom. The energy equations are coupled by a relaxation time which measures the time required for the vibrational energy component to equilibrate with the translational and rotational energy components. An improved relaxation time is used in this thesis. The equations are solved numerically using the Steger-Warming flux vector splitting method and the Implicit MacCormack method. The results show that uniform flow is produced outside of the boundary layer. Nonequilibrium exists in both the converging and diverging nozzle sections. The boundary layer region is characterized by a marked increase in translational-rotational temperature. The vibrational temperature remains frozen downstream of the nozzle, except in the boundary layer.
Understanding Non-equilibrium Thermodynamics Foundations, Applications, Frontiers
Jou, David; Lebon, Georgy
2007-01-01
This book offers a homogeneous presentation of the many faces of non-equilibrium thermodynamics. The first part is devoted to a description of the nowadays thermodynamic formalism recognized as the classical theory of non-equilibrium processes. This part of the book may serve as a basis to an introductory course dedicated to first-year graduate students in sciences and engineering. The classical description can however not be complete, as it rests on the hypothesis of local equilibrium. This has fostered the development of many theories going beyond local equilibrium and which cannot be put aside. The second part of the book is concerned with these different approaches, and will be of special interest for PhD students and researchers. For the sake of homogeneity, the authors have used the general structure and methods presented in the first part. Indeed, besides their differences, all these formalisms are not closed boxes but present some overlappings and parallelisms which are emphasized in this book. For pe...
Homogeneous non-equilibrium two-phase critical flow model
International Nuclear Information System (INIS)
Schroeder, J.J.; Vuxuan, N.
1987-01-01
An important aspect of nuclear and chemical reactor safety is the ability to predict the maximum or critical mass flow rate from a break or leak in a pipe system. At the beginning of such a blowdown, if the stagnation condition of the fluid is subcooled or slightly saturated thermodynamic non-equilibrium exists in the downstream, e.g. the fluid becomes superheated to a degree determined by the liquid pressure. A simplified non-equilibrium model, explained in this report, is valid for rapidly decreasing pressure along the flow path. It presumes that fluid has to be superheated by an amount governed by physical principles before it starts to flash into steam. The flow is assumed to be homogeneous, i.e. the steam and liquid velocities are equal. An adiabatic flow calculation mode (Fanno lines) is employed to evaluate the critical flow rate for long pipes. The model is found to satisfactorily describe critical flow tests. Good agreement is obtained with the large scale Marviken tests as well as with small scale experiments. (orig.)
Nonequilibrium Equation of State in Suspensions of Active Colloids
Directory of Open Access Journals (Sweden)
Félix Ginot
2015-01-01
Full Text Available Active colloids constitute a novel class of materials composed of colloidal-scale particles locally converting chemical energy into motility, mimicking micro-organisms. Evolving far from equilibrium, these systems display structural organizations and dynamical properties distinct from thermalized colloidal assemblies. Harvesting the potential of this new class of systems requires the development of a conceptual framework to describe these intrinsically nonequilibrium systems. We use sedimentation experiments to probe the nonequilibrium equation of state of a bidimensional assembly of active Janus microspheres and conduct computer simulations of a model of self-propelled hard disks. Self-propulsion profoundly affects the equation of state, but these changes can be rationalized using equilibrium concepts. We show that active colloids behave, in the dilute limit, as an ideal gas with an activity-dependent effective temperature. At finite density, increasing the activity is similar to increasing adhesion between equilibrium particles. We quantify this effective adhesion and obtain a unique scaling law relating activity and effective adhesion in both experiments and simulations. Our results provide a new and efficient way to understand the emergence of novel phases of matter in active colloidal suspensions.
NON-EQUILIBRIUM ELECTRONS IN THE OUTSKIRTS OF GALAXY CLUSTERS
Energy Technology Data Exchange (ETDEWEB)
Avestruz, Camille; Nagai, Daisuke; Lau, Erwin T. [Department of Physics, Yale University, New Haven, CT 06520 (United States); Nelson, Kaylea, E-mail: camille.avestruz@yale.edu, E-mail: camille.avestruz@yale.edu [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520 (United States)
2015-08-01
The analysis of X-ray and Sunyaev–Zel’dovich measurements of the intracluster medium (ICM) assumes that electrons are in thermal equilibrium with ions in the plasma. However, in the outskirts of galaxy clusters, the electron–ion equilibration timescale can become comparable to the Hubble time, leading to systematic biases in cluster mass estimates and mass-observable scaling relations. To quantify an upper limit of the impact of non-equilibrium electrons, we use a mass-limited sample of simulated galaxy clusters taken from a cosmological simulation with a two-temperature model that assumes the Spitzer equilibration time for the electrons and ions. We show that the temperature bias is more pronounced in more massive and rapidly accreting clusters. For the most extreme case, we find that the bias is of the order of 10% at half of the cluster virial radius and increases to 40% at the edge of the cluster. Gas in filaments is less susceptible to the non-equilibrium effect, leading to azimuthal variations in the temperature bias at large cluster-centric radii. Using mock Chandra observations of simulated clusters, we show that the bias manifests in ultra-deep X-ray observations of cluster outskirts and quantify the resulting biases in hydrostatic mass and cluster temperature derived from these observations. We provide a mass-dependent fitting function for the temperature bias profile, which can be useful for modeling the effect of electron-ion equilibration in galaxy clusters.
Non-equilibrium turbulence scalings in turbulent planar jets
Cafiero, Gioacchino; Vassilicos, John Christos; Turbulence, Mixing; Flow Control Group Team
2017-11-01
A revised version of the Townsend George theory, as proposed by Dairay et al. 2015, is applied to the study of turbulent planar jets (Cafiero and Vassilicos 2017). Requiring the self-similarity of only few quantities along with the non-equilibrium dissipation scaling law (Vassilicos 2015), it implies new mean flow and jet width scalings. In particular, the ratio of characteristic cross-stream to centreline streamwise velocities decays as the -1/3 power of streamwise distance in the region where the non-equilibrium dissipation scaling holds. In the definition of Cɛ both in Dairay et al. 2015 and in Cafiero and Vassilicos 2017 the local Reynolds number is based on the local flow width rather than on the integral lengthscale. We verify that the ratio of the integral lengthscale to the flow width is constant, thus enabling the use of the integral flow width in place of the integral lengthscale for defining Cɛ. The importance of this result is twofold: firstly it further strengthens the scalings obtained in the works of Dairay et al. 2015 and Cafiero and Vassilicos 2017; secondly the flow width is immediately accessible by any mean flow measurement, whereas the estimation of the integral lengthscale often requires an additional hypothesis. ERC Advanced Grant 320560.
The stable nonequilibrium state of bicarbonate aqueous systems
Voeikov, V. L.; Vilenskaya, N. D.; Ha, Do Minh; Malyshenko, S. I.; Buravleva, E. V.; Yablonskaya, O. I.; Timofeev, K. N.
2012-09-01
Data obtained by electron paramagnetic resonance (EPR) and chemiluminescence analysis indicate that in aqueous solutions of bicarbonates, superoxide radical and other reactive oxygen species (ROS) are constantly produced. The stationary level of the superoxide radical is found to increase when a solution is illuminated. Reactions involving ROS are shown to be accompanied by the generation of electron excitation energy, keeping bicarbonate solutions in a stable nonequilibrium state. The system can emit part of this energy. Variations in emitting activity are found to correlate with variations in the cosmophysical factors. The emitting activity of solutions is found to vary in the presence of low and ultralow concentrations of hydrated fullerenes. It is noted that the phenomenon of spontaneous charge separation in aqueous systems (G. H. Pollack) could play a role in maintaining a stable nonequilibrium state in bicarbonate systems where the reactions with ROS participation are catalyzed by forms of carbonate. It is concluded that the abovementioned properties of bicarbonate aqueous systems most likely keep living matter whose structural basis is formed by these systems in a stable excited state, thereby making it highly sensitive to the action of external factors with low and ultralow intensities.
Non-Equilibrium Turbulence and Two-Equation Modeling
Rubinstein, Robert
2011-01-01
Two-equation turbulence models are analyzed from the perspective of spectral closure theories. Kolmogorov theory provides useful information for models, but it is limited to equilibrium conditions in which the energy spectrum has relaxed to a steady state consistent with the forcing at large scales; it does not describe transient evolution between such states. Transient evolution is necessarily through nonequilibrium states, which can only be found from a theory of turbulence evolution, such as one provided by a spectral closure. When the departure from equilibrium is small, perturbation theory can be used to approximate the evolution by a two-equation model. The perturbation theory also gives explicit conditions under which this model can be valid, and when it will fail. Implications of the non-equilibrium corrections for the classic Tennekes-Lumley balance in the dissipation rate equation are drawn: it is possible to establish both the cancellation of the leading order Re1/2 divergent contributions to vortex stretching and enstrophy destruction, and the existence of a nonzero difference which is finite in the limit of infinite Reynolds number.
Variational discretization of the nonequilibrium thermodynamics of simple systems
Gay-Balmaz, François; Yoshimura, Hiroaki
2018-04-01
In this paper, we develop variational integrators for the nonequilibrium thermodynamics of simple closed systems. These integrators are obtained by a discretization of the Lagrangian variational formulation of nonequilibrium thermodynamics developed in (Gay-Balmaz and Yoshimura 2017a J. Geom. Phys. part I 111 169–93 Gay-Balmaz and Yoshimura 2017b J. Geom. Phys. part II 111 194–212) and thus extend the variational integrators of Lagrangian mechanics, to include irreversible processes. In the continuous setting, we derive the structure preserving property of the flow of such systems. This property is an extension of the symplectic property of the flow of the Euler–Lagrange equations. In the discrete setting, we show that the discrete flow solution of our numerical scheme verifies a discrete version of this property. We also present the regularity conditions which ensure the existence of the discrete flow. We finally illustrate our discrete variational schemes with the implementation of an example of a simple and closed system.
Mesoscopic non-equilibrium thermodynamic analysis of molecular motors.
Kjelstrup, S; Rubi, J M; Pagonabarraga, I; Bedeaux, D
2013-11-28
We show that the kinetics of a molecular motor fueled by ATP and operating between a deactivated and an activated state can be derived from the principles of non-equilibrium thermodynamics applied to the mesoscopic domain. The activation by ATP, the possible slip of the motor, as well as the forward stepping carrying a load are viewed as slow diffusion along a reaction coordinate. Local equilibrium is assumed in the reaction coordinate spaces, making it possible to derive the non-equilibrium thermodynamic description. Using this scheme, we find expressions for the velocity of the motor, in terms of the driving force along the spacial coordinate, and for the chemical reaction that brings about activation, in terms of the chemical potentials of the reactants and products which maintain the cycle. The second law efficiency is defined, and the velocity corresponding to maximum power is obtained for myosin movement on actin. Experimental results fitting with the description are reviewed, giving a maximum efficiency of 0.45 at a myosin headgroup velocity of 5 × 10(-7) m s(-1). The formalism allows the introduction and test of meso-level models, which may be needed to explain experiments.
The Martian Energetic Radiation Environment Models
Gonçalves, Patrícia; Keating, Ana; Truscott, Pete; Lei, Fan; Desorgher, Laurent; Heynderickx, Daniel; Crosby, Norma Bock; Nieminen, Petteri; Santin, Giovanni
The Martian Energetic Radiation Environment Models The high energy ionising radiation environment in the solar system consists of three main sources: the planetary radiation belts, galactic cosmic rays and solar energetic particles. Future Mars missions potentially carry significant risk from long-term exposure to ionising radiation. The Martian Energetic Radiation Environment Models, MEREM, were developed in order to simulate the Martian radiation environment. The models, eMEREM and dMEREM, respec-tively engineering and detailed Martian Energetic Radiation Environment Models, are based on the Geant4 and FLUKA radiation transport programs, combined with Mars Climate Database model for the atmosphere. MOLA (Mars Orbiter Laser Altimeter) data and gamma-ray spec-trometer data have been used to define surface topology and surface composition (including presence of water), respectively. Although the models are capable of operating on standalone mode, a SPENVIS (space envi-ronment information system) compatible, web-based user interface was developed to provide an integrated environment to predict the Martian radiation and greatly simplify the operation of the software by non-experts and by future mission developers. Results of the Mars Energetic Radiation Environment Models concerning the estimate of effec-tive doses and ambient dose equivalents for potential Martian landing sites having regard to the combined incidence, under solar minimum and solar maximum conditions, of flare related particle radiation and background galactic cosmic ray radiation are presented.
Influence of processing variations on microstructure and properties in Fe/Co/2--3%V alloys
International Nuclear Information System (INIS)
Pinnel, M.R.; Bennett, J.E.
1974-01-01
A microstructural evaluation was used to provide the key to the understanding of the numerous phase changes which occur in this alloy and their influence on drawability and magnetic properties. Samples of two compositions (2.5 percent V and 3.0 percent V) were given the standard processing sequence used in the production of remanent reed electrical contacts with selected alterations in annealing temperatures at several stages. Microstructures were characterized following each step by light microscopy on lightly etched sections using differential interference contrast and were correlated with the appropriate ternary equilibrium diagram. Results indicate that the typical hot rolled (1200 0 C) and air cooled structure is composed of a nonequilibrium, vanadium supersaturated, bcc phase produced by a massive transformation during cooling and is also subject to an ordering transformation. The resultant microstructure is too brittle to be drawn into wire. This can be modified by more rapid cooling. However, the hot rolled and ice brine quenched structure which is more martensitic in character and a totally disordered, nonequilibrium, bcc phase provides only modest improvement in ductility. (U.S.)
About the leak microstructures
Lombardi, M.; Guoxiang, H. Huo-J.; Lombardi, F. S.
2001-04-01
The capabilities of a new microstructure, anode point based, for the detection of gas ionizing radiations are presented. For every single detected ionizing radiation it gives a pair of "induced" charges (anodic and cathodic) of the same amount (pulses of the same amplitudes), of opposite sign, with the same collection time and essentially in time coincidence, that are proportional to the primary ionization collected. Each pulse of a pair gives the same energy and timing information, thus one can be used for these information and the other for the position. The complete lack of insulating materials in the active volume of this microstructure avoids problems of charging-up and makes its behaviour stable and repeatable. Primary avalanches with a size of more than 2.5×10 7 electrons (4 pC) giving current pulses with a peak of more than 0.26 mA on 100 Ω and about 30 ns duration are possible with 5.9 keV X-rays of 55Fe working in proportional region and in isobutane gas. Single electrons emitted by a heated filament ( EcPoison Superfish and Mafia programs, are presented.
Inhomogeneous microstructural growth by irradiation
DEFF Research Database (Denmark)
Krishan, K.; Singh, Bachu Narain; Leffers, Torben
1985-01-01
In the present paper we discuss the development of heterogeneous microstructure for uniform irradiation conditions. It is shown that microstructural inhomogeneities on a scale of 0.1 μm can develop purely from kinematic considerations because of the basic structure of the rate equations used...
Microstructured hollow fibers for ultrafiltration
Culfaz, Pmar Zeynep; Culfaz, P.Z.; Rolevink, Hendrikus H.M.; van Rijn, C.J.M.; Lammertink, Rob G.H.; Wessling, Matthias
2010-01-01
Hollow fiber ultrafiltration membranes with a corrugated outer microstructure were prepared from a PES/PVP blend. The effect of spinning parameters such as air gap, take-up speed, polymer dope viscosity and coagulation value on the microstructure and membrane characteristics was investigated. Fibers
Marshall Mccall, Patrick
turnover on the steady-state properties of collections of filaments remained unclear. Here, I reconstituted tunable, non-equilibrium actin turnover dynamics in entangled solutions of actin filaments as a model of the actin cortex of living cells. We found that this non-equilibrium turnover decouples solution mechanics from microstructure, enabling structurally indistinguishable materials to behave effectively as either viscous fluids or elastic gels. Additionally, we employed computer simulations to identify the dynamical regime in which actin turnover controls the effective viscosity of 2D cross-linked actin networks in the presence of motors. Additionally, I examine in this thesis the localization and self-assembly of actin filaments in condensed liquid phases called polyelectrolyte coacervates as a model membrane-less organelle. We find that concentration of actin through spontaneous partitioning preferentially to the coacervate phase accelerates the assembly of filaments. These filaments then localize to the coacervate-bulk interface, generating particles with visco-elastic shells surrounding liquid cores. In this case, the properties of the condensed phase enable regulation of actin assembly dynamics.
Cizek, P.; Wynne, B. P.; Davies, C. H. J.; Hodgson, P. D.
2015-01-01
The present work investigates the transformation behavior of a low-carbon Mo-Nb linepipe steel and the corresponding transformation product microstructures using deformation dilatometry. The continuous cooling transformation (CCT) diagrams have been constructed for both the fully recrystallized austenite and that deformed in uniaxial compression at 1148 K (875 °C) to a strain of 0.5 for cooling rates ranging from 0.1 to about 100 K/s. The obtained microstructures have been studied in detail using electron backscattered diffraction complemented by transmission electron microscopy. Heavy deformation of the parent austenite has caused a significant expansion of the polygonal ferrite transformation field in the CCT diagram, as well as a shift in the non-equilibrium ferrite transformation fields toward higher cooling rates. Furthermore, the austenite deformation has resulted in a pronounced refinement in both the effective grain (sheaf/packet) size and substructure unit size of the non-equilibrium ferrite microstructures. The optimum microstructure expected to display an excellent balance between strength and toughness is a mix of quasi-polygonal ferrite and granular bainite (often termed "acicular ferrite") produced from the heavily deformed austenite within a processing window covering the cooling rates from about 10 to about 100 K/s.
2015-01-01
such as voids [20,22-24], shear banding [25], dislocation pile -ups [26,27], and crystal size [28] have been proposed to affect hot spot formation...Detonation, Combustion , 1st Edition ed., Elsevier, Boston, 2003, pp. 101-123. [26] Armstrong,RW, Rev. Adv. Mater. Sci. 19 (2009) 13-40. [27] Field...S, Int. J. Therm. Sci. 50 (2011) 2117-21. [35] Khaneft,AV, Duginov,EV, Combust . Explo. Shock Waves. 48 (2012) 699-704. [36] Wood,MA, van Duin,ACT
Plasma diagnostics of non-equilibrium atmospheric plasma jets
Shashurin, Alexey; Scott, David; Keidar, Michael; Shneider, Mikhail
2014-10-01
Intensive development and biomedical application of non-equilibrium atmospheric plasma jet (NEAPJ) facilitates rapid growth of the plasma medicine field. The NEAPJ facility utilized at the George Washington University (GWU) demonstrated efficacy for treatment of various cancer types (lung, bladder, breast, head, neck, brain and skin). In this work we review recent advances of the research conducted at GWU concerned with the development of NEAPJ diagnostics including Rayleigh Microwave Scattering setup, method of streamer scattering on DC potential, Rogowski coils, ICCD camera and optical emission spectroscopy. These tools allow conducting temporally-resolved measurements of plasma density, electrical potential, charge and size of the streamer head, electrical currents flowing though the jet, ionization front propagation speed etc. Transient dynamics of plasma and discharge parameters will be considered and physical processes involved in the discharge will be analyzed including streamer breakdown, electrical coupling of the streamer tip with discharge electrodes, factors determining NEAPJ length, cross-sectional shape and propagation path etc.
Newton-Krylov methods applied to nonequilibrium radiation diffusion
International Nuclear Information System (INIS)
Knoll, D.A.; Rider, W.J.; Olsen, G.L.
1998-01-01
The authors present results of applying a matrix-free Newton-Krylov method to a nonequilibrium radiation diffusion problem. Here, there is no use of operator splitting, and Newton's method is used to convert the nonlinearities within a time step. Since the nonlinear residual is formed, it is used to monitor convergence. It is demonstrated that a simple Picard-based linearization produces a sufficient preconditioning matrix for the Krylov method, thus elevating the need to form or store a Jacobian matrix for Newton's method. They discuss the possibility that the Newton-Krylov approach may allow larger time steps, without loss of accuracy, as compared to an operator split approach where nonlinearities are not converged within a time step
Nonequilibrium fluctuations in micro-MHD effects on electrodeposition
International Nuclear Information System (INIS)
Aogaki, Ryoichi; Morimoto, Ryoichi; Asanuma, Miki
2010-01-01
In copper electrodeposition under a magnetic field parallel to electrode surface, different roles of two kinds of nonequilibrium fluctuations for micro-magnetohydrodynamic (MHD) effects are discussed; symmetrical fluctuations are accompanied by the suppression of three dimensional (3D) nucleation by micro-MHD flows (the 1st micro-MHD effect), whereas asymmetrical fluctuations controlling 2D nucleation yield secondary nodules by larger micro-MHD flows (the 2nd micro-MHD effect). Though the 3D nucleation with symmetrical fluctuations is always suppressed by the micro-MHD flows, due to the change in the rate-determining step from electron transfer to mass transfer, the 2D nucleation with asymmetrical fluctuations newly turns unstable, generating larger micro-MHD flows. As a result, round semi-spherical deposits, i.e., secondary nodules are yielded. Using computer simulation, the mechanism of the 2nd micro-MHD effect is validated.
Nonequilibrium Transport through a Spinful Quantum Dot with Superconducting Leads
DEFF Research Database (Denmark)
Andersen, Brian Møller; Flensberg, Karsten; Koerting, Verena
2011-01-01
We study the nonlinear cotunneling current through a spinful quantum dot contacted by two superconducting leads. Applying a general nonequilibrium Green function formalism to an effective Kondo model, we study the rich variation in the IV characteristics with varying asymmetry in the tunnel...... coupling to source and drain electrodes. The current is found to be carried, respectively, by multiple Andreev reflections in the symmetric limit, and by spin-induced Yu-Shiba-Rusinov bound states in the strongly asymmetric limit. The interplay between these two mechanisms leads to qualitatively different...... IV characteristics in the crossover regime of intermediate symmetry, consistent with recent experimental observations of negative differential conductance and repositioned conductance peaks in subgap cotunneling spectroscopy....
Sampling rare events in nonequilibrium and nonstationary systems.
Berryman, Joshua T; Schilling, Tanja
2010-12-28
Although many computational methods for rare event sampling exist, this type of calculation is not usually practical for general nonequilibrium conditions, with macroscopically irreversible dynamics and away from both stationary and metastable states. A novel method for calculating the time-series of the probability of a rare event is presented which is designed for these conditions. The method is validated for the cases of the Glauber-Ising model under time-varying shear flow, the Kawasaki-Ising model after a quench into the region between nucleation dominated and spinodal decomposition dominated phase change dynamics, and the parallel open asymmetric exclusion process. The method requires a subdivision of the phase space of the system: it is benchmarked and found to scale well for increasingly fine subdivisions, meaning that it can be applied without detailed foreknowledge of the physically important reaction pathways.
Majorana fermion modulated nonequilibrium transport through double quantum dots
International Nuclear Information System (INIS)
Deng, Ming-Xun; Wang, Rui-Qiang; Ai, Bao-Quan; Yang, Mou; Hu, Liang-Bin; Zhong, Qing-Hu; Wang, Guang-Hui
2014-01-01
Nonequilibrium electronic transports through a double-QD-Majorana coupling system are studied with a purpose to extract the information to identify Majorana bound states (MBSs). It is found that MBSs can help form various transport processes, including the nonlocal crossed Andreev reflection, local resonant Andreev reflection, and cotunneling, depending on the relative position of two dot levels. These processes enrich the signature of average currents and noise correlations to probe the nature of MBSs. We further demonstrate the switching between the current peaks of crossed Andreev reflection and cotunneling, which is closely related to the nonlocal nature of Majorana fermions. We also propose effective physical pictures to understand these Majorana-assisted transports. - Highlights: • Majorana fermions are characterized in the signature of currents and noises. • Three types of tunneling mechanisms are realized separately. • The switching of crossed Andreev reflection and cotunneling is realized. • Concrete physical pictures are proposed to understand Majorana-assisted transports
Stationary Distribution and Thermodynamic Relation in Nonequilibrium Steady States
Komatsu, Teruhisa S.
2010-01-01
We describe our recent attempts toward statistical mechanics and thermodynamics for nonequilibrium steady states (NESS) realized, e.g., in a heat conducting system. Our first result is a simple expression of the probability distribution (of microscopic states) of a NESS. Our second result is a natural extension of the thermodynamic Clausius relation and a definition of an accompanying entropy in NESS. This entropy coincides with the normalization constant appearing in the above mentioned microscopic expression of NESS, and has an expression similar to the Shannon entropy (with a further symmetrization). The NESS entropy proposed here is a clearly defined measurable quantity even in a system with a large degrees of freedom. We numerically measure the NESS entropy in hardsphere fluid systems with a heat current, by observing energy exchange between the system and the heat baths when the temperatures of the baths are changed according to specified protocols.
Nonequilibrium chiral fluid dynamics including dissipation and noise
International Nuclear Information System (INIS)
Nahrgang, Marlene; Herold, Christoph; Bleicher, Marcus; Leupold, Stefan
2011-01-01
We present a consistent theoretical approach for the study of nonequilibrium effects in chiral fluid dynamics within the framework of the linear σ model with constituent quarks. Treating the quarks as an equilibrated heat bath, we use the influence functional formalism to obtain a Langevin equation for the σ field. This allows us to calculate the explicit form of the damping coefficient and the noise correlators. For a self-consistent derivation of both the dynamics of the σ field and the quark fluid, we have to employ the 2PI (two-particle irreducible) effective action formalism. The energy dissipation from the field to the fluid is treated in the exact formalism of the 2PI effective action where a conserved energy-momentum tensor can be constructed. We derive its form and comment on approximations generating additional terms in the energy-momentum balance of the entire system.
Eu, Byung Chan
2016-01-01
This book presents the fundamentals of irreversible thermodynamics for nonlinear transport processes in gases and liquids, as well as for generalized hydrodynamics extending the classical hydrodynamics of Navier, Stokes, Fourier, and Fick. Together with its companion volume on relativistic theories, it provides a comprehensive picture of the kinetic theory formulated from the viewpoint of nonequilibrium ensembles in both nonrelativistic and, in Vol. 2, relativistic contexts. Theories of macroscopic irreversible processes must strictly conform to the thermodynamic laws at every step and in all approximations that enter their derivation from the mechanical principles. Upholding this as the inviolable tenet, the author develops theories of irreversible transport processes in fluids (gases or liquids) on the basis of irreversible kinetic equations satisfying the H theorem. They apply regardless of whether the processes are near to or far removed from equilibrium, or whether they are linear or nonlinear with respe...
Exactly solvable nonequilibrium Langevin relaxation of a trapped nanoparticle
International Nuclear Information System (INIS)
Salazar, Domingos S P; Lira, Sérgio A
2016-01-01
In this work, we study the nonequilibrium statistical properties of the relaxation dynamics of a nanoparticle trapped in a harmonic potential. We report an exact time-dependent analytical solution to the Langevin dynamics that arises from the stochastic differential equation of our system’s energy in the underdamped regime. By utilizing this stochastic thermodynamics approach, we are able to completely describe the heat exchange process between the nanoparticle and the surrounding environment. As an important consequence of our results, we observe the validity of the heat exchange fluctuation theorem in our setup, which holds for systems arbitrarily far from equilibrium conditions. By extending our results for the case of N noninterating nanoparticles, we perform analytical asymptotic limits and direct numerical simulations that corroborate our analytical predictions. (paper)
Non-equilibrium dissipative supramolecular materials with a tunable lifetime
Tena-Solsona, Marta; Rieß, Benedikt; Grötsch, Raphael K.; Löhrer, Franziska C.; Wanzke, Caren; Käsdorf, Benjamin; Bausch, Andreas R.; Müller-Buschbaum, Peter; Lieleg, Oliver; Boekhoven, Job
2017-07-01
Many biological materials exist in non-equilibrium states driven by the irreversible consumption of high-energy molecules like ATP or GTP. These energy-dissipating structures are governed by kinetics and are thus endowed with unique properties including spatiotemporal control over their presence. Here we show man-made equivalents of materials driven by the consumption of high-energy molecules and explore their unique properties. A chemical reaction network converts dicarboxylates into metastable anhydrides driven by the irreversible consumption of carbodiimide fuels. The anhydrides hydrolyse rapidly to the original dicarboxylates and are designed to assemble into hydrophobic colloids, hydrogels or inks. The spatiotemporal control over the formation and degradation of materials allows for the development of colloids that release hydrophobic contents in a predictable fashion, temporary self-erasing inks and transient hydrogels. Moreover, we show that each material can be re-used for several cycles.
Nonequilibrium sensing and its analogy to kinetic proofreading
Hartich, David; Barato, Andre C.; Seifert, Udo
2015-05-01
For a paradigmatic model of chemotaxis, we analyze the effect of how a nonzero affinity driving receptors out of equilibrium affects sensitivity. This affinity arises whenever changes in receptor activity involve adenosine triphosphate hydrolysis. The sensitivity integrated over a ligand concentration range is shown to be enhanced by the affinity, providing a measure of how much energy consumption improves sensing. With this integrated sensitivity we can establish an intriguing analogy between sensing with nonequilibrium receptors and kinetic proofreading: the increase in integrated sensitivity is equivalent to the decrease of the error in kinetic proofreading. The influence of the occupancy of the receptor on the phosphorylation and dephosphorylation reaction rates is shown to be crucial for the relation between integrated sensitivity and affinity. This influence can even lead to a regime where a nonzero affinity decreases the integrated sensitivity, which corresponds to anti-proofreading.
Nonequilibrium quark production in the expanding QCD plasma
Tanji, Naoto; Berges, Jürgen
2018-02-01
We perform real-time lattice simulations of nonequilibrium quark production in the longitudinally expanding QCD plasma. Starting from a highly occupied gluonic state with vacuum quark sector, we extract the time evolution of quark and gluon number densities per unit transverse area and rapidity. The total quark number shows after an initial rapid increase an almost linear growth with time. Remarkably, this growth rate appears to be consistent with a simple kinetic theory estimate involving only two-to-two scattering processes in small-angle approximation. This extends previous findings about the role of two-to-two scatterings for purely gluonic dynamics in accordance with the early stages of the bottom-up thermalization scenario.
Non-equilibrium steady states in supramolecular polymerization
Sorrenti, Alessandro; Leira-Iglesias, Jorge; Sato, Akihiro; Hermans, Thomas M.
2017-06-01
Living systems use fuel-driven supramolecular polymers such as actin to control important cell functions. Fuel molecules like ATP are used to control when and where such polymers should assemble and disassemble. The cell supplies fresh ATP to the cytosol and removes waste products to sustain steady states. Artificial fuel-driven polymers have been developed recently, but keeping them in sustained non-equilibrium steady states (NESS) has proven challenging. Here we show a supramolecular polymer that can be kept in NESS, inside a membrane reactor where ATP is added and waste removed continuously. Assembly and disassembly of our polymer is regulated by phosphorylation and dephosphorylation, respectively. Waste products lead to inhibition, causing the reaction cycle to stop. Inside the membrane reactor, however, waste can be removed leading to long-lived NESS conditions. We anticipate that our approach to obtain NESS can be applied to other stimuli-responsive materials to achieve more life-like behaviour.
Infrared behavior of the gluon propagator in nonequilibrium situations
Cooper, F; Nayak, G C
2002-01-01
The infrared behavior of the medium modified gluon propagator in nonequilibrium situations is studied in the covariant gauge using the Schwinger-Keldysh closed-time path formalism. It is shown that the magnetic screening mass is nonzero at the one loop level whenever the initial gluon distribution function is nonisotropic with the assumption that the distribution function of the gluon is not divergent at zero transverse momentum. For isotropic gluon distribution functions, such as those describing local equilibrium, the magnetic mass at the one loop level is zero, which is consistent with finite temperature field theory results. Assuming that a reasonable initial gluon distribution function can be obtained from a perturbative QCD calculation of minijets, we determine these out of equilibrium values for the initial magnetic and Debye screening masses at energy densities appropriate to BNL RHIC and CERN LHC. We also compare the magnetic masses obtained here with those obtained using finite temperature lattice Q...
Quantum gases finite temperature and non-equilibrium dynamics
Szymanska, Marzena; Davis, Matthew; Gardiner, Simon
2013-01-01
The 1995 observation of Bose-Einstein condensation in dilute atomic vapours spawned the field of ultracold, degenerate quantum gases. Unprecedented developments in experimental design and precision control have led to quantum gases becoming the preferred playground for designer quantum many-body systems. This self-contained volume provides a broad overview of the principal theoretical techniques applied to non-equilibrium and finite temperature quantum gases. Covering Bose-Einstein condensates, degenerate Fermi gases, and the more recently realised exciton-polariton condensates, it fills a gap by linking between different methods with origins in condensed matter physics, quantum field theory, quantum optics, atomic physics, and statistical mechanics. Thematically organised chapters on different methodologies, contributed by key researchers using a unified notation, provide the first integrated view of the relative merits of individual approaches, aided by pertinent introductory chapters and the guidance of ed...
Applications of nonequilibrium melting concept to damage-accumulation processes
International Nuclear Information System (INIS)
Lam, N.Q.; Okamoto, P.R.
1998-01-01
The authors recent study of crystalline-to-amorphous transformation led to the successful development of a unified thermodynamic description of disorder-induced amorphization and heat-induced melting, based on a generalized version of the Lindemann melting criterion. The generalized criterion requires that the melting temperature of a defective crystal decreases with increasing static atomic disorder. Hence, any crystal can melt at temperatures below the melting point of its perfect crystalline state when driven far from equilibrium by introducing critical amounts of misfitting solute atoms and lattice imperfections, radiation damage, and/or tensile stresses. This conceptual approach to nonequilibrium melting provides new insight into long-standing materials problems such as brittle fracture, embrittlement, and environmentally-induced cracking, for example irradiation-assisted stress corrosion cracking
Nonequilibrium shock layer temperature profiles from arc jet radiation measurements
Blackwell, Harvel E.; Yuen, Eric; Scott, Carl D.; Arepalli, Sivaram
1989-01-01
Shock layer temperature profiles are obtained through analysis of radiation from shock layers produced by a blunt body inserted in arc jet flow. Spectral measurements have been made in a nitrogen flow of 54.4 gm/s at an enthalpy of 8.72 MJ/kg. Vibrational temperatures for N2+ are obtained by matching spectral regions from arc jet spectra with spectra generated using the NEQAIR code. Temperature profiles obtained from the radiation layers show a vibrational temperature higher than the rotational temperature near the front of the shock and both temperatures decrease as the flow approaches the body. The spectral measurements are made and analysis completed for four distances, from the surface of the blunt body. The corresponding shock layer thickness is approximately 3.6 cm. Although the shock layer appears to be in thermal nonequilibrium, the measured rotational temperature approaches the single temperature results of viscous shock layer calculations at this test condition.
NATO Advanced Study Institute on Nonequilibrium Phonon Dynamics
1985-01-01
Phonons are always present in the solid state even at an absolute temperature of 0 K where zero point vibrations still abound. Moreover, phonons interact with all other excitations of the solid state and, thereby, influence most of its properties. Historically experimental information on phonon transport came from measurements of thermal conductivity. Over the past two decades much more, and much more detailed, information on phonon transport and on many of the inherent phonon interaction processes have come to light from experiments which use nonequilibrium phonons to study their dynamics. The resultant research field has most recently blossomed with the development of ever more sophisticated experimental and theoretical methods which can be applied to it. In fact, the field is moving so rapidly that new members of the research community have difficulties in keeping up to date. This NATO Advanced Study Institute (ASI) was organized with the objective of overcoming the information barrier between those expert...
Biological Implications of Dynamical Phases in Non-equilibrium Networks
Murugan, Arvind; Vaikuntanathan, Suriyanarayanan
2016-03-01
Biology achieves novel functions like error correction, ultra-sensitivity and accurate concentration measurement at the expense of free energy through Maxwell Demon-like mechanisms. The design principles and free energy trade-offs have been studied for a variety of such mechanisms. In this review, we emphasize a perspective based on dynamical phases that can explain commonalities shared by these mechanisms. Dynamical phases are defined by typical trajectories executed by non-equilibrium systems in the space of internal states. We find that coexistence of dynamical phases can have dramatic consequences for function vs free energy cost trade-offs. Dynamical phases can also provide an intuitive picture of the design principles behind such biological Maxwell Demons.
Nonequilibrium statistical operator in hot-electron transport theory
International Nuclear Information System (INIS)
Xing, D.Y.; Liu, M.
1991-09-01
The Nonequilibrium Statistical Operator method developed by Zubarev is generalized and applied to the study of hot-electron transport in semiconductors. The steady-state balance equations for momentum and energy are derived to the lowest order in the electron-lattice coupling. We show that the derived balance equations are exactly the same as those obtained by Lei and Ting. This equivalence stems from the fact that to the linear order in the electron-lattice coupling, two statistical density matrices have identical effect when they are used to calculate the average value of a dynamical operator. The application to the steady-state and transient hot-electron transport in multivalley semiconductors is also discussed. (author). 28 refs, 1 fig
Applications of nonequilibrium melting concept to damage-accumulation processes
Energy Technology Data Exchange (ETDEWEB)
Lam, N.Q.; Okamoto, P.R.
1998-01-01
The authors recent study of crystalline-to-amorphous transformation led to the successful development of a unified thermodynamic description of disorder-induced amorphization and heat-induced melting, based on a generalized version of the Lindemann melting criterion. The generalized criterion requires that the melting temperature of a defective crystal decreases with increasing static atomic disorder. Hence, any crystal can melt at temperatures below the melting point of its perfect crystalline state when driven far from equilibrium by introducing critical amounts of misfitting solute atoms and lattice imperfections, radiation damage, and/or tensile stresses. This conceptual approach to nonequilibrium melting provides new insight into long-standing materials problems such as brittle fracture, embrittlement, and environmentally-induced cracking, for example irradiation-assisted stress corrosion cracking.
Thermal Non-equilibrium Consistent with Widespread Cooling
Winebarger, A.; Lionello, R.; Mikic, Z.; Linker, J.; Mok, Y.
2014-01-01
Time correlation analysis has been used to show widespread cooling in the solar corona; this cooling has been interpreted as a result of impulsive (nanoflare) heating. In this work, we investigate wide-spread cooling using a 3D model for a solar active region which has been heated with highly stratified heating. This type of heating drives thermal non-equilibrium solutions, meaning that though the heating is effectively steady, the density and temperature in the solution are not. We simulate the expected observations in narrowband EUV images and apply the time correlation analysis. We find that the results of this analysis are qualitatively similar to the observed data. We discuss additional diagnostics that may be applied to differentiate between these two heating scenarios.
A non-equilibrium formulation of food security resilience
Vaitla, Bapu
2017-01-01
Resilience, the ability to recover from adverse events, is of fundamental importance to food security. This is especially true in poor countries, where basic needs are frequently threatened by economic, environmental and health shocks. An empirically sound formalization of the concept of food security resilience, however, is lacking. Here, we introduce a general non-equilibrium framework for quantifying resilience based on the statistical notion of persistence. Our approach can be applied to any food security variable for which high-frequency time-series data are available. We illustrate our method with per capita kilocalorie availability for 161 countries between 1961 and 2011. We find that resilient countries are not necessarily those that are characterized by high levels or less volatile fluctuations of kilocalorie intake. Accordingly, food security policies and programmes will need to be tailored not only to welfare levels at any one time, but also to long-run welfare dynamics. PMID:28280586
Nonequilibrium interactions between ideal polymers and a repulsive surface.
Halifa Levi, Raz; Kantor, Yacov
2017-08-01
We use Newtonian and overdamped Langevin dynamics to study long flexible polymers dragged by an external force at a constant velocity v. The work W performed by that force depends on the initial state of the polymer and the details of the process. The Jarzynski equality can be used to relate the nonequilibrium work distribution P(W) obtained from repeated experiments to the equilibrium free energy difference ΔF between the initial and final states. We use the power law dependence of the geometrical and dynamical characteristics of the polymer on the number of monomers N to suggest the existence of a critical velocity v_{c}(N), such that for vdragged away from a repulsive wall. Our results suggest that the distribution of the dissipated work W_{d}=W-ΔF in properly scaled variables approaches a limiting shape for large N.
Nonequilibrium evaporation and condensation during a uranium dioxide fuel expansion
International Nuclear Information System (INIS)
Refling, J.G. Jr.
1976-01-01
Effects of nonequilibrium rates of evaporation and condensation on the expansion of two-phase fuel in an LMFBR core disruptive accident were studied. The rates were determined from kinetic theory. Conservation equations for mass, momentum and energy were written for both phases. The resulting equations were solved numerically and compared with analyses which assumed that thermodynamic equilibrium could be maintained throughout the expansion. A parametric study was performed on the effective liquid-surface area, which includes the effects of both liquid surface area and the evaporation and condensation coefficients. Liquid and two-phase thermodynamic properties for the fuel were already available; however, gas phase properties were developed as part of this study
Vibrational population distributions in nonequilibrium nozzle expansion flows
Watt, W. S.; Rich, J. W.
1971-01-01
Experimental measurements and theoretical calculations of the vibrational population distribution in nonequilibrium nozzle expansion flows of gas mixtures are reported. These studies were directed toward determining whether vibrational energy exchange pumping could lead to laser action on the vibrational bands of a diatomic molecule. Three different types of experiments were conducted. These showed (1) that vibrational energy was preferentially transferred from N2 to CO in supersonic nozzle flows containing these gases; (2) that under some conditions this vibrational energy exchange pumping mechanism created population inversions in the vibrational levels of CO; and (3) that at large expansion ratios the magnitude of these population inversions was sufficient to sustain lasing in the nozzle. A theoretical model was developed to calculate vibrational state population distributions in gas dynamic expansions of a mixture of diatomic gases. Although only isothermal calculations have been completed, these data indicate that population inversions are predicted for conditions similar to those obtained in the nozzle expansion flows.
Nonlinear Peltier effect and the nonequilibrium Jonson-Mahan theorem
Directory of Open Access Journals (Sweden)
J.K.Freericks
2006-01-01
Full Text Available We generalize the many-body formalism for the Peltier effect to the nonlinear/nonequilibrium regime corresponding to large amplitude (spatially uniform but time-dependent electric fields. We find a relationship between the expectation values for the charge current and for the part of the heat current that reduces to the Jonson-Mahan theorem in the linear-response regime. The nonlinear-response Peltier effect has an extra term in the heat current that is related to Joule heating (we are unable to fully analyze this term. The formalism holds in all dimensions and for arbitrary many-body systems that have local interactions. We illustrate it for the Falicov-Kimball, Hubbard, and periodic Anderson models.
Dynamical Symmetries and Causality in Non-Equilibrium Phase Transitions
Directory of Open Access Journals (Sweden)
Malte Henkel
2015-11-01
Full Text Available Dynamical symmetries are of considerable importance in elucidating the complex behaviour of strongly interacting systems with many degrees of freedom. Paradigmatic examples are cooperative phenomena as they arise in phase transitions, where conformal invariance has led to enormous progress in equilibrium phase transitions, especially in two dimensions. Non-equilibrium phase transitions can arise in much larger portions of the parameter space than equilibrium phase transitions. The state of the art of recent attempts to generalise conformal invariance to a new generic symmetry, taking into account the different scaling behaviour of space and time, will be reviewed. Particular attention will be given to the causality properties as they follow for co-variant n-point functions. These are important for the physical identification of n-point functions as responses or correlators.
DEFF Research Database (Denmark)
Henriksen, Jonas Rosager; Sabra, Mads Christian; Mouritsen, Ole G.
2000-01-01
The nonequilibrium, steady-state phase transitions and the structure of the different phases of a two-dimensional system with two thermodynamic temperatures are studied via a simple lattice-gas model with mobile active impurities ("hot/cold spots'') whose activity is controlled by an external drive....... The properties of the model are calculated by Monte Carlo computer-simulation techniques. The two temperatures and the external drive on the system lead to a rich phase diagram including regions of microstructured phases in addition to macroscopically ordered (phase-separated) and disordered phases. Depending...
Energetics of geostrophic adjustment in rotating flow
Juan, Fang; Rongsheng, Wu
2002-09-01
Energetics of geostrophic adjustment in rotating flow is examined in detail with a linear shallow water model. The initial unbalanced flow considered first falls tinder two classes. The first is similar to that adopted by Gill and is here referred to as a mass imbalance model, for the flow is initially motionless but with a sea surface displacement. The other is the same as that considered by Rossby and is referred to as a momentum imbalance model since there is only a velocity perturbation in the initial field. The significant feature of the energetics of geostrophic adjustment for the above two extreme models is that although the energy conversion ratio has a large case-to-case variability for different initial conditions, its value is bounded below by 0 and above by 1 / 2. Based on the discussion of the above extreme models, the energetics of adjustment for an arbitrary initial condition is investigated. It is found that the characteristics of the energetics of geostrophic adjustment mentioned above are also applicable to adjustment of the general unbalanced flow under the condition that the energy conversion ratio is redefined as the conversion ratio between the change of kinetic energy and potential energy of the deviational fields.
Migration on Wings Aerodynamics and Energetics
Kantha, Lakshmi
2012-01-01
This book is an effort to explore the technical aspects associated with bird flight and migration on wings. After a short introduction on the birds migration, the book reviews the aerodynamics and Energetics of Flight and presents the calculation of the Migration Range. In addition, the authors explains aerodynamics of the formation flight and finally introduces great flight diagrams.
Error propagation in energetic carrying capacity models
Pearse, Aaron T.; Stafford, Joshua D.
2014-01-01
Conservation objectives derived from carrying capacity models have been used to inform management of landscapes for wildlife populations. Energetic carrying capacity models are particularly useful in conservation planning for wildlife; these models use estimates of food abundance and energetic requirements of wildlife to target conservation actions. We provide a general method for incorporating a foraging threshold (i.e., density of food at which foraging becomes unprofitable) when estimating food availability with energetic carrying capacity models. We use a hypothetical example to describe how past methods for adjustment of foraging thresholds biased results of energetic carrying capacity models in certain instances. Adjusting foraging thresholds at the patch level of the species of interest provides results consistent with ecological foraging theory. Presentation of two case studies suggest variation in bias which, in certain instances, created large errors in conservation objectives and may have led to inefficient allocation of limited resources. Our results also illustrate how small errors or biases in application of input parameters, when extrapolated to large spatial extents, propagate errors in conservation planning and can have negative implications for target populations.
Energetic utilization of dietary fiber in pigs
Rijnen, M.M.J.A.
2003-01-01
The energetic utilization of fermentable dietary fiber (fDF) of different fiber sources and its relation to physical activity and housing conditions was studied in three experiments. In all experiments the daily intake of digestible nutrients, nitrogen and energy balances, heat production, and
Radiation hormesis: an ecological and energetic perspective.
Parsons, P A
2001-09-01
Organisms in natural habitats are exposed to an array of environmental stresses, which all have energetic costs. Under this ecological scenario, hormesis for ionizing radiation becomes an evolutionary expectation at exposures substantially exceeding background. This conclusion implies that some relaxation of radiation protection criteria is worthy of serious consideration. Copyright 2001 Harcourt Publishers Ltd.
Estimating Instantaneous Energetic Cost During Gait Adaptation
2014-08-31
energetic penalties imposed by various gait disabilities, and the 30 evaluation of the effectiveness of rehabilitation interventions at mitigating...Jarasch R. Energy expenditure and biomechanical characteristics of 412 lower limb amputee gait:: The influence of prosthetic alignment and
Energetic utilisation of biomass in Hungary
International Nuclear Information System (INIS)
Barotfi, I.
1994-01-01
Energetic utilisation of biomass has been known since prehistoric times and was only pushed into the background by the technological developments of the last century. The energy crisis and, more recently, environmental problems have now brought it back to the fore, and efforts are being made worldwide to find modern technical applications for biomass and contribute to its advance. (orig.) [de
Cryocycling of energetic materials. Final report
Energy Technology Data Exchange (ETDEWEB)
Griffiths, S.; Nilson, R.; Handrock, J.; Revelli, V.; Weingarten, L. [and others
1997-08-01
The Cryocycling of Energetic Materials Project was executed in the period FY`94-96 as a Life Cycle Engineering activity in the Memorandum of Understanding (MOU) on advanced conventional munitions. This MOU is an agreement between the Departments of Energy and Defense (Office of Munitions) that facilitates the development of technologies of mutual interest to the two Departments. The cryocycling process is a safe, environmentally friendly, and cost effective means of rubblizing bulk energetic materials so that they can be easily reused in a variety of new products. For this reason, cryocycling of excess solid energetic materials is one of the recycle/reuse strategies under study for demilitarized munitions in the Departments of Energy and Defense. These strategies seek to minimize the environmental damage associated with disposal of decommissioned energetic materials. In addition, they encourage technologies that can be used to derive economic benefit from reuse/reapplication of materials that would otherwise be treated as hazardous wastes. 45 refs., 38 figs., 7 tabs.
Energetic Systems and Nanotechnology - A Look Ahead
National Research Council Canada - National Science Library
Kavetsky, Robert; Anand, Davinder; Goldwasser, Judah; Bruck, Hugh; Doherty, Ruth; Armstrong, Ron
2005-01-01
... in insensitive munitions built around the idea of "Combat Safe" Insensitive Munitions (CSIM); and 2) the importance of developing the next generation of in-house experts in energetic systems who will carry on a tradition of transitioning breakthrough research into military systems.
Energetic materials standards – Chemical compatibility
Tuukkanen, I.M.; Bouma, R.H.B.
2014-01-01
Subgroup A Energetic Materials Team, SG/A (EMT), develops and maintains standards that are relevant to all life-cycle phases of ammunition/weapon systems. STANAG 4147 is the standard regarding chemical compatibility of explosives with munition components, and is a document of prime importance.
Energetic constraints on species coexistence in birds
Pigot, Alexander L.; Tobias, Joseph A.; Jetz, Walter
2016-01-01
The association between species richness and ecosystem energy availability is one of the major geographic trends in biodiversity. It is often explained in terms of energetic constraints, such that coexistence among competing species is limited in low productivity environments. However, it has proven
Non-equilibrium stochastic dynamics in continuum: The free case
Directory of Open Access Journals (Sweden)
Y.Kondratiev
2008-12-01
Full Text Available We study the problem of identification of a proper state-space for the stochastic dynamics of free particles in continuum, with their possible birth and death. In this dynamics, the motion of each separate particle is described by a fixed Markov process M on a Riemannian manifold X. The main problem arising here is a possible collapse of the system, in the sense that, though the initial configuration of particles is locally finite, there could exist a compact set in X such that, with probability one, infinitely many particles will arrive at this set at some time t>0. We assume that X has infinite volume and, for each α���1, we consider the set Θα of all infinite configurations in X for which the number of particles in a compact set is bounded by a constant times the α-th power of the volume of the set. We find quite general conditions on the process M which guarantee that the corresponding infinite particle process can start at each configuration from Θα, will never leave Θα, and has cadlag (or, even, continuous sample paths in the vague topology. We consider the following examples of applications of our results: Brownian motion on the configuration space, free Glauber dynamics on the configuration space (or a birth-and-death process in X, and free Kawasaki dynamics on the configuration space. We also show that if X=Rd, then for a wide class of starting distributions, the (non-equilibrium free Glauber dynamics is a scaling limit of (non-equilibrium free Kawasaki dynamics.
Modeling Inflation Using a Non-Equilibrium Equation of Exchange
Chamberlain, Robert G.
2013-01-01
Inflation is a change in the prices of goods that takes place without changes in the actual values of those goods. The Equation of Exchange, formulated clearly in a seminal paper by Irving Fisher in 1911, establishes an equilibrium relationship between the price index P (also known as "inflation"), the economy's aggregate output Q (also known as "the real gross domestic product"), the amount of money available for spending M (also known as "the money supply"), and the rate at which money is reused V (also known as "the velocity of circulation of money"). This paper offers first a qualitative discussion of what can cause these factors to change and how those causes might be controlled, then develops a quantitative model of inflation based on a non-equilibrium version of the Equation of Exchange. Causal relationships are different from equations in that the effects of changes in the causal variables take time to play out-often significant amounts of time. In the model described here, wages track prices, but only after a distributed lag. Prices change whenever the money supply, aggregate output, or the velocity of circulation of money change, but only after a distributed lag. Similarly, the money supply depends on the supplies of domestic and foreign money, which depend on the monetary base and a variety of foreign transactions, respectively. The spreading of delays mitigates the shocks of sudden changes to important inputs, but the most important aspect of this model is that delays, which often have dramatic consequences in dynamic systems, are explicitly incorporated.macroeconomics, inflation, equation of exchange, non-equilibrium, Athena Project
Nonequilibrium 2-hydroxyoctadecanoic acid monolayers: effect of electrolytes.
Lendrum, Conrad D; Ingham, Bridget; Lin, Binhua; Meron, Mati; Toney, Michael F; McGrath, Kathryn M
2011-04-19
2-Hydroxyacids display complex monolayer phase behavior due to the additional hydrogen bonding afforded by the presence of the second hydroxy group. The placement of this group at the position α to the carboxylic acid functionality also introduces the possibility of chelation, a utility important in crystallization including biomineralization. Biomineralization, like many biological processes, is inherently a nonequilibrium process. The nonequilibrium monolayer phase behavior of 2-hydroxyoctadecanoic acid was investigated on each of pure water, calcium chloride, sodium bicarbonate and calcium carbonate crystallizing subphases as a precursor study to a model calcium carbonate biomineralizing system, each at a pH of ∼6. The role of the bicarbonate co-ion in manipulating the monolayer structure was determined by comparison with monolayer phase behavior on a sodium chloride subphase. Monolayer phase behavior was probed using surface pressure/area isotherms, surface potential, Brewster angle microscopy, and synchrotron-based grazing incidence X-ray diffraction and X-ray reflectivity. Complex phase behavior was observed for all but the sodium chloride subphase with hydrogen bonding, electrostatic and steric effects defining the symmetry of the monolayer. On a pure water subphase hydrogen bonding dominates with three phases coexisting at low pressures. Introduction of calcium ions into the aqueous subphase ensures strong cation binding to the surfactant head groups through chelation. The monolayer becomes very unstable in the presence of bicarbonate ions within the subphase due to short-range hydrogen bonding interactions between the monolayer and bicarbonate ions facilitated by the sodium cation enhancing surfactant solubility. The combined effects of electrostatics and hydrogen bonding are observed on the calcium carbonate crystallizing subphase. © 2011 American Chemical Society
Equilibrium and nonequilibrium dynamics of soft sphere fluids.
Ding, Yajun; Mittal, Jeetain
2015-07-14
We use computer simulations to test the freezing-point scaling relationship between equilibrium transport coefficients (self-diffusivity, viscosity) and thermodynamic parameters for soft sphere fluids. The fluid particles interact via the inverse-power potential (IPP), and the particle softness is changed by modifying the exponent of the distance-dependent potential term. In the case of IPP fluids, density and temperature are not independent variables and can be combined to obtain a coupling parameter to define the thermodynamic state of the system. We find that the rescaled coupling parameter, based on its value at the freezing point, can approximately collapse the diffusivity and viscosity data for IPP fluids over a wide range of particle softness. Even though the collapse is far from perfect, the freezing-point scaling relationship provides a convenient and effective way to compare the structure and dynamics of fluid systems with different particle softness. We further show that an alternate scaling relationship based on two-body excess entropy can provide an almost perfect collapse of the diffusivity and viscosity data below the freezing transition. Next, we perform nonequilibrium molecular dynamics simulations to calculate the shear-dependent viscosity and to identify the distinct role of particle softness in underlying structural changes associated with rheological properties. Qualitatively, we find a similar shear-thinning behavior for IPP fluids with different particle softness, though softer particles exhibit stronger shear-thinning tendency. By investigating the distance and angle-dependent pair correlation functions in these systems, we find different structural features in the case of IPP fluids with hard-sphere like and softer particle interactions. Interestingly, shear-thinning in hard-sphere like fluids is accompanied by enhanced translational order, whereas softer fluids exhibit loss of order with shear. Our results provide a systematic evaluation
Nonequilibrium forces following quenches in active and thermal matter
Rohwer, Christian M.; Solon, Alexandre; Kardar, Mehran; Krüger, Matthias
2018-03-01
Nonequilibrium systems with conserved quantities like density or momentum are known to exhibit long-ranged correlations. This, in turn, leads to long-ranged fluctuation-induced (Casimir) forces, predicted to arise in a variety of nonequilibrium settings. Here, we study such forces, which arise transiently between parallel plates or compact inclusions in a gas of particles, following a change ("quench") in temperature or activity of the medium. Analytical calculations, as well as numerical simulations of passive or active Brownian particles, indicate two distinct forces: (i) The immediate effect of the quench is adsorption or desorption of particles of the medium to the immersed objects, which in turn initiates a front of relaxing (mean) density. This leads to time-dependent density-induced forces. (ii) A long-term effect of the quench is that density fluctuations are modified, manifested as transient (long-ranged) (pair-)correlations that relax diffusively to their (short-ranged) steady-state limit. As a result, transient fluctuation-induced forces emerge. We discuss the properties of fluctuation-induced and density-induced forces as regards universality, relaxation as a function of time, and scaling with distance between objects. Their distinct signatures allow us to distinguish the two types of forces in simulation data. Our simulations also show that a quench of the effective temperature of an active medium gives rise to qualitatively similar effects to a temperature quench in a passive medium. Based on this insight, we propose several scenarios for the experimental observation of the forces described here.
Semiconductors and semimetals epitaxial microstructures
Willardson, Robert K; Beer, Albert C; Gossard, Arthur C
1994-01-01
Newly developed semiconductor microstructures can now guide light and electrons resulting in important consequences for state-of-the-art electronic and photonic devices. This volume introduces a new generation of epitaxial microstructures. Special emphasis has been given to atomic control during growth and the interrelationship between the atomic arrangements and the properties of the structures.Key Features* Atomic-level control of semiconductor microstructures* Molecular beam epitaxy, metal-organic chemical vapor deposition* Quantum wells and quantum wires* Lasers, photon(IR)detectors, heterostructure transistors
Advances in magnetospheric physics, 1971--1974: energetic particles
International Nuclear Information System (INIS)
West, H.I. Jr.
1974-12-01
An account is given of energetic particle research in magnetospheric physics for the time period 1971--1974. Emphasis is on relating the various aspects of energetic particles to magnetospheric processes. 458 refs. (U.S.)
International Nuclear Information System (INIS)
Masaaki Suzuki; Shinsuke Mori; Noritaka Matsumoto; Hiroshi Akatsuka
1999-01-01
The local separation factor and the local nonequilibrium degree just behind the plasma region were obtained. The plasma gas compositions measured by the enthalpy probe system were substantially thermodynamic nonequilibrium conditions, when the input energy was 4 J/cm 3 . The measured maximum value of the separation factor was 1.01, although it changed locally. The measured separation factor and its nonequilibrium condition were discussed. Anyway, the only small value obtained in this experiments is similar to the recent data obtained by Kurchatov group and is less than published data, which is measured spectroscopically [ru
Black hole evaporation in a heat bath as a nonequilibrium process and its final fate
International Nuclear Information System (INIS)
Saida, Hiromi
2007-01-01
We consider a black hole in a heat bath, and the whole system which consists of the black hole and the heat bath is isolated from outside environments. When the black hole evaporates, the Hawking radiation causes an energy flow from the black hole to the heat bath. Therefore, since no energy flow arises in an equilibrium state, the thermodynamic state of the whole system is not in equilibrium. That is, in a region around the black hole, the matter field of Hawking radiation and that of heat bath should be in a nonequilibrium state due to the energy flow. Using a simple model which reflects the nonequilibrium nature of energy flow, we find the nonequilibrium effect on a black hole evaporation as follows: if the nonequilibrium region around a black hole is not so large, the evaporation time scale of a black hole in a heat bath becomes longer than that in an empty space (a situation without heat bath), because of the incoming energy flow from the heat bath to the black hole. However, if the nonequilibrium region around a black hole is sufficiently large, the evaporation time scale in a heat bath becomes shorter than that in an empty space, because a nonequilibrium effect of the temperature difference between the black hole and heat bath appears as a strong energy extraction from the black hole by the heat bath. Further, a specific nonequilibrium phenomenon is found: a quasi-equilibrium evaporation stage under the nonequilibrium effect proceeds abruptly to a quantum evaporation stage at a semi-classical level (at black hole radius R g > Planck length) within a very short time scale with a strong burst of energy. (Contrarily, when the nonequilibrium effect is not taken into account, a quasi-equilibrium stage proceeds smoothly to a quantum stage at R g < Planck length without so strong an energy burst.) That is, the nonequilibrium effect of energy flow tends to make a black hole evaporation process more dynamical and to accelerate that process. Finally, on the final fate
Non-equilibrium plasma chemistry at high pressure and its applications
International Nuclear Information System (INIS)
Bai Xiyao; Zhang Zhitao; Bai Mindong; Zhu Qiaoying
2000-01-01
A review is presented of research and development of gas discharge and non-equilibrium plasma including, new ideas of non-equilibrium plasma at high gas pressure. With special technology, strong electric fields (>400 Td) can be achieved by which electrons are accelerated suddenly, becoming high energy electrons (> 10 eV) at high pressure. On impact with the electrons, the gas molecules dissociate into ions, atomic ions, atoms and free radicals, and new substances or molecules can be synthesized through custom design. Chemical reaction difficult to achieve by conventional method can be realized or accelerated. Non-equilibrium plasma chemistry at high pressure has wide application prospects
Non-Equilibrium Thermodynamic Chemistry and the Composition of the Atmosphere of Mars
Levine, J. S.; Summers, M. E.
2003-01-01
A high priority objective of the Mars Exploration Program is to Determine if life exists today (MEPAG Goal I, Objective A). The measurement of gases of biogenic origin may be an approach to detect the presence of microbial life on the surface or subsurface of Mars. Chemical thermodynamic calculations indicate that on both Earth and Mars, certain gases should exist in extremely low concentrations, if at all. Microbial metabolic activity is an important non-equilibrium chemistry process on Earth, and if microbial life exists on Mars, may be an important nonequilibrium chemistry process on Mars. The non-equilibrium chemistry of the atmosphere of Mars is discussed in this paper.
Flux-split algorithms for flows with non-equilibrium chemistry and vibrational relaxation
Grossman, B.; Cinnella, P.
1990-01-01
The present consideration of numerical computation methods for gas flows with nonequilibrium chemistry thermodynamics gives attention to an equilibrium model, a general nonequilibrium model, and a simplified model based on vibrational relaxation. Flux-splitting procedures are developed for the fully-coupled inviscid equations encompassing fluid dynamics and both chemical and internal energy-relaxation processes. A fully coupled and implicit large-block structure is presented which embodies novel forms of flux-vector split and flux-difference split algorithms valid for nonequilibrium flow; illustrative high-temperature shock tube and nozzle flow examples are given.
High-temperature expansion for nonequilibrium steady states in driven lattice gases.
Lefevere, Raphael; Tasaki, Hal
2005-05-27
We develop a controlled high-temperature expansion for nonequilibrium steady states of the driven lattice gas, the "Ising model" for nonequilibrium physics. We represent the steady state as P(eta) alpha e(-betaH(eta)-psi(eta)) and evaluate the lowest order contribution to the nonequilibrium effective interaction psi(eta). We see that, in dimensions d > or = 2, all models with nonsingular transition rates yield the same summable psi(eta), suggesting the possibility of describing the state as a Gibbs state similar to equilibrium. The models with the Metropolis rule show exceptional behavior.
Assessment of accident energetics in LMFBR core-disruptive accidents
International Nuclear Information System (INIS)
Fauske, H.K.
1977-01-01
An assessment of accident energetics in LMFBR core-disruptive accidents is given with emphasis on the generic issues of energetic recriticality and energetic fuel-coolant interaction events. Application of a few general behavior principles to the oxide-fueled system suggests that such events are highly unlikely following a postulated core meltdown event
Kawakatsu, T.; Matsuyama, A.; Ohta, T.; Tanaka, H.; Tanaka, S.
2011-07-01
Soft matter is a rapidly growing interdisciplinary research field covering a range of subject areas including physics, chemistry, biology, mathematics and engineering. Some of the important universal features of these materials are their mesoscopic structures and their dynamics. Due to the existence of such large-scale structures, which nevertheless exhibit interactions of the order of the thermal energy, soft matter can readily be taken out of equilibrium by imposing a weak external field such as an electric field, a mechanical stress or a shear flow. The importance of the coexistence of microscopic molecular dynamics and the mesoscopic/macroscopic structures and flows requires us to develop hierarchical approaches to understand the nonlinear and nonequilibrium phenomena, which is one of the central issues of current soft matter research. This special section presents selected contributions from the 'International Symposium on Non-Equilibrium Soft Matter 2010' held from 17-20 August 2010 in Nara, Japan, which aimed to describe recent advances in soft matter research focusing especially on its nonequilibrium aspects. The topics discussed cover statics and dynamics of a wide variety of materials ranging from traditional soft matter like polymers, gels, emulsions, liquid crystals and colloids to biomaterials such as biopolymers and biomembranes. Among these studies, we highlighted the physics of biomembranes and vesicles, which has attracted great attention during the last decade; we organized a special session for this active field. The work presented in this issue deals with (1) structure formation in biomembranes and vesicles, (2) rheology of polymers and gels, (3) mesophases in block copolymers, (4) mesoscopic structures in liquid crystals and ionic liquids, and (5) nonequilibrium dynamics. This symposium was organized as part of a research project supported by the Grant-in-Aid for the priority area 'Soft Matter Physics' (2006-2010) from the Ministry of Education
Modelling microstructural evolution under irradiation
International Nuclear Information System (INIS)
Tikare, V.
2015-01-01
Microstructural evolution of materials under irradiation is characterised by some unique features that are not typically present in other application environments. While much understanding has been achieved by experimental studies, the ability to model this microstructural evolution for complex materials states and environmental conditions not only enhances understanding, it also enables prediction of materials behaviour under conditions that are difficult to duplicate experimentally. Furthermore, reliable models enable designing materials for improved engineering performance for their respective applications. Thus, development and application of mesoscale microstructural model are important for advancing nuclear materials technologies. In this chapter, the application of the Potts model to nuclear materials will be reviewed and demonstrated, as an example of microstructural evolution processes. (author)
Computer vision in microstructural analysis
Srinivasan, Malur N.; Massarweh, W.; Hough, C. L.
1992-01-01
The following is a laboratory experiment designed to be performed by advanced-high school and beginning-college students. It is hoped that this experiment will create an interest in and further understanding of materials science. The objective of this experiment is to demonstrate that the microstructure of engineered materials is affected by the processing conditions in manufacture, and that it is possible to characterize the microstructure using image analysis with a computer. The principle of computer vision will first be introduced followed by the description of the system developed at Texas A&M University. This in turn will be followed by the description of the experiment to obtain differences in microstructure and the characterization of the microstructure using computer vision.
Micromagnetism and the microstructure of ferromagnetic solids
Kronmüller, Helmut
2003-01-01
Here is a fundamental introduction to microstructure magnetic property relations where microstructures on atomic, nano- and micrometer scales are considered. The authors demonstrate that outstanding magnetic properties require an optimization of microstructural properties where the microstructures in crystalline materials are point defects and dislocations as well as grain and phase boundaries. In amorphous alloys the type of microstructures on atomic scales are defined and used to describe intrinsic and extrinsic properties.
Thermal Conductivity of Liquid Water from Reverse Nonequilibrium Ab Initio Molecular Dynamics
Tsuchida, Eiji
2018-02-01
We report on a theoretical framework for calculating the thermal conductivity of liquid water from first principles with the aid of the linear scaling method. We also discuss the possibility of obtaining equilibrium properties from a nonequilibrium trajectory.
Nonequilibrium Contribution to the Rate of Reaction. III. Isothermal Multicomponent Systems
Shizgal, B.; Karplus, M.
1970-10-01
The nonequilibrium contribution to the reaction rate of an isothermal multicomponent system is obtained by solution of the appropriate Chapman-Enskog equation; the system is composed of reactive species in contact with a heat bath of inert atoms M.
De Visser, P.J.; Goldie, D.J.; Diener, P.; Withington, S.; Baselmans, J.J.A.; Klapwijk, T.M.
2014-01-01
In a superconductor, absorption of photons with an energy below the superconducting gap leads to redistribution of quasiparticles over energy and thus induces a strong nonequilibrium quasiparticle energy distribution. We have measured the electrodynamic response, quality factor, and resonant
Non-equilibrium concentration fluctuations in binary liquids with realistic boundary conditions.
Ortiz de Zárate, J M; Kirkpatrick, T R; Sengers, J V
2015-09-01
Because of the spatially long-ranged nature of spontaneous fluctuations in thermal non-equilibrium systems, they are affected by boundary conditions for the fluctuating hydrodynamic variables. In this paper we consider a liquid mixture between two rigid and impervious plates with a stationary concentration gradient resulting from a temperature gradient through the Soret effect. For liquid mixtures with large Lewis and Schmidt numbers, we are able to obtain explicit analytical expressions for the intensity of the non-equilibrium concentration fluctuations as a function of the frequency ω and the wave number q of the fluctuations. In addition we elucidate the spatial dependence of the intensity of the non-equilibrium fluctuations responsible for a non-equilibrium Casimir effect.
Non-equilibrium thermodynamics of radiation-induced processes in solids
International Nuclear Information System (INIS)
Yurov, V.M.; Eshchanov, A.N.; Kuketaev, A.T.; Sidorenya, Yu.S.
2005-01-01
In the paper an item about a defect system response in solids on external action (temperature, pressure, light, etc.) from the point of view of non-equilibrium statistical thermodynamics is considered
Glushak, P. A.; Markiv, B. B.; Tokarchuk, M. V.
2018-01-01
We present a generalization of Zubarev's nonequilibrium statistical operator method based on the principle of maximum Renyi entropy. In the framework of this approach, we obtain transport equations for the basic set of parameters of the reduced description of nonequilibrium processes in a classical system of interacting particles using Liouville equations with fractional derivatives. For a classical systems of particles in a medium with a fractal structure, we obtain a non-Markovian diffusion equation with fractional spatial derivatives. For a concrete model of the frequency dependence of a memory function, we obtain generalized Kettano-type diffusion equation with the spatial and temporal fractality taken into account. We present a generalization of nonequilibrium thermofield dynamics in Zubarev's nonequilibrium statistical operator method in the framework of Renyi statistics.
Non-Equilibrium Heavy Flavored Hadron Yields from Chemical Equilibrium Strangeness-Rich QGP
Kuznetsova, Inga; Rafelski, Johann
2008-01-01
The yields of heavy flavored hadrons emitted from strangeness-rich QGP are evaluated within chemical non-equilibrium statistical hadronization model, conserving strangeness, charm, and entropy yields at hadronization.
RareNoise: non-equilibrium effects in detectors of gravitational waves
Energy Technology Data Exchange (ETDEWEB)
Conti, L [INFN, Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Bonaldi, M [Istituto di Fotonica e Nanotecnologie, CNR-Fondazione Bruno Kessler, 38100 Povo, Trento (Italy); Rondoni, L, E-mail: Livia.Conti@pd.infn.i [Dip. di Matematica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy)
2010-04-21
The RareNoise project investigates non-equilibrium effects in gravitational wave detectors. We illustrate the physics behind the project and the planned project development, involving experimental, numerical and theoretical research.
Non-Equilibrium Superconductivity and Quasiparticle Dynamics in YBa(2)Cu(3)O(7)
International Nuclear Information System (INIS)
The authors use optical pump, coherent terahertz probe spectroscopy to transiently excite nonequilibrium populations of quasiparticles in YBa 2 Cu 3 O 7.δ and monitor, with picosecond resolution, the superfluid and quasiparticle dynamics
One-dimensional two-phase reacting gas nonequilibrium performance program
Cherry, S. S.; Frey, H. M.; Kliegel, J. R.; Quan, V.
1968-01-01
Computer program calculates the inviscid one-dimensional equilibrium, frozen, and nonequilibrium nozzle expansion of propellant exhaust mixtures containing carbon, hydrogen, oxygen, nitrogen, fluorine, chlorine and either aluminum, beryllium, boron or lithium. This program performs calculations for conical nozzles only.
Non-equilibrium reactive flux: A unified framework for slow and fast reaction kinetics.
Bose, Amartya; Makri, Nancy
2017-10-21
The flux formulation of reaction rate theory is recast in terms of the expectation value of the reactive flux with an initial condition that corresponds to a non-equilibrium, factorized reactant density. In the common case of slow reactive processes, the non-equilibrium expression reaches the plateau regime only slightly slower than the equilibrium flux form. When the reactants are described by a single quantum state, as in the case of electron transfer reactions, the factorized reactant density describes the true initial condition of the reactive process. In such cases, the time integral of the non-equilibrium flux expression yields the reactant population as a function of time, allowing characterization of the dynamics in cases where there is no clear separation of time scales and thus a plateau regime cannot be identified. The non-equilibrium flux offers a unified approach to the kinetics of slow and fast chemical reactions and is ideally suited to mixed quantum-classical methods.
Fragmentation function in non-equilibrium QCD using closed-time path integral formalism
International Nuclear Information System (INIS)
Nayak, Gouranga C.
2009-01-01
In this paper we implement the Schwinger-Keldysh closed-time path integral formalism in non-equilibrium QCD in accordance to the definition of the Collins-Soper fragmentation function. We consider a high-p T parton in QCD medium at initial time τ 0 with an arbitrary non-equilibrium (non-isotropic) distribution function f(vector (p)) fragmenting to a hadron. We formulate the parton-to-hadron fragmentation function in non-equilibrium QCD in the light-cone quantization formalism. It may be possible to include final-state interactions with the medium via a modification of the Wilson lines in this definition of the non-equilibrium fragmentation function. This may be relevant to the study of hadron production from a quark-gluon plasma at RHIC and LHC. (orig.)
Grossman, B.; Garrett, J.; Cinnella, P.
1989-01-01
Several versions of flux-vector split and flux-difference split algorithms were compared with regard to general applicability and complexity. Test computations were performed using curve-fit equilibrium air chemistry for an M = 5 high-temperature inviscid flow over a wedge, and an M = 24.5 inviscid flow over a blunt cylinder for test computations; for these cases, little difference in accuracy was found among the versions of the same flux-split algorithm. For flows with nonequilibrium chemistry, the effects of the thermodynamic model on the development of flux-vector split and flux-difference split algorithms were investigated using an equilibrium model, a general nonequilibrium model, and a simplified model based on vibrational relaxation. Several numerical examples are presented, including nonequilibrium air chemistry in a high-temperature shock tube and nonequilibrium hydrogen-air chemistry in a supersonic diffuser.
Nonequilibrium phase transition in a system with chaotic dynamics. The ABCDE model
Friedrich, R.; Haken, H.
1992-04-01
For the ABCDE model, a low-dimensional dynamical system devised to study the generation of magnetic fields by convective fluid motions, we examine a nonequilibrium phase transition in a system with chaotic dynamics.
Capriz, Gianfranco
1989-01-01
This book proposes a new general setting for theories of bodies with microstructure when they are described within the scheme of the con tinuum: besides the usual fields of classical thermomechanics (dis placement, stress, temperature, etc.) some new fields enter the picture (order parameters, microstress, etc.). The book can be used in a semester course for students who have already followed lectures on the classical theory of continua and is intended as an introduction to special topics: materials with voids, liquid crystals, meromorphic con tinua. In fact, the content is essentially that of a series of lectures given in 1986 at the Scuola Estiva di Fisica Matematica in Ravello (Italy). I would like to thank the Scientific Committee of the Gruppo di Fisica Matematica of the Italian National Council of Research (CNR) for the invitation to teach in the School. I also thank the Committee for Mathematics of CNR and the National Science Foundation: they have supported my research over many years and given ...
Non-Equilibrium Containerless Solidification of Aluminum-Nickel Alloys
Ilbagi, Arash
More than 90% of all metallic materials are manufactured starting from their liquid state. Designing the solid structure produced during solidification can have major savings in downstream processing. Rapid solidification yields significant enhancement in properties through refined microstructure, reduced microsegregation and the formation of metastable phases. To control the microstructure obtained from rapid solidification and attain desired properties, understanding of effects of processing parameters, in particular cooling rate and undercooling on microstructure evolution is required. In the case of peritectic reaction this understanding is lacking. In this dissertation, the effect of cooling rate on the peritectic reactions occurring in the binary Al-Ni system is investigated. Impulse Atomization technique was used to produce rapidly solidified particles of Al-36 wt%Ni and Al-50wt%Ni. The effect of cooling rate on the microstructure evolution and phase fractions achieved after solidification was studied. Also, porosity formation in the atomized particles was investigated and the effect of processing parameters on the amount and distribution of porosity was analyzed. For characterization, neutron diffraction, X-ray micro-tomography, electron and optical microscopy were utilized. The results showed that in both Al-36 wt%Ni and Al-50 wt%Ni, cooling rate has a significant effect on the formation of microstructure, phase fractions and metastable phase formation. It was shown that at different cooling rate ii regimes different mechanisms are responsible for the changes observed in the phase fractions. Using X-Ray tomography, multiple nucleation sites were observed in large particles, while smaller particles contained only a single nucleation site. Also, porosity within the particles was quantified and the distribution of porosity with regard to the nucleation site and cooling rate is discussed. The distribution of porosity within the small particles and large
Non-equilibrium dynamics of open systems and fluctuation-dissipation theorems
Czech Academy of Sciences Publication Activity Database
Špička, Václav; Velický, B.; Kalvová, Anděla
2017-01-01
Roč. 65, 6-8 (2017), s. 1-23, č. článku 1700032. ISSN 0015-8208 Institutional support: RVO:68378271 Keywords : non-equilibrium * fluctuation-dissipation theorems * non-equilibrium Greens function * transient and steady state magnetic current * molecular bridge Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 2.434, year: 2016
Bresme, F; Armstrong, J
2014-01-07
We report non-equilibrium molecular dynamics simulations of heat transport in models of molecular fluids. We show that the "local" thermal conductivities obtained from non-equilibrium molecular dynamics simulations agree within numerical accuracy with equilibrium Green-Kubo computations. Our results support the local equilibrium hypothesis for transport properties. We show how to use the local dependence of the thermal gradients to quantify the thermal conductivity of molecular fluids for a wide range of thermodynamic states using a single simulation.
International Nuclear Information System (INIS)
Arkhipov, V.I.; Rudenko, A.I.
1979-01-01
The effect of changes of radiation stimulation permittivity on nonequilibrium conductivity of dielectrics and high-resistance conductors in a radiation field has been studied theoretically. The plane-parallel sample under the constant voltage has been irradiated by penetrating radiation. The uniform radiation caused the transfer the current carriers from traps to the conduction band. The dependence of permittivity on charged traps concentration is shown to lead to negative nonequilibrium conductivity of high-resistance materials
The behavior of matter under nonequilibrium conditions: Fundamental aspects and applications
International Nuclear Information System (INIS)
Prigogine, I.
1989-10-01
As in the previous period, our work has been concerned with the study of the properties of nonequilibrium systems and especially with the mechanism of self-organization. As is well-known, the study of self-organization began with the investigation of hydrodynamical or chemical instabilities studied from the point of view of macroscopic physics. The main outcome is that nonequilibrium generates spatial correlations of macroscopic physics. The main outcome is that nonequilibrium generates spatial correlations of macroscopic range whose characteristics length is an intrinsic property and whose amplitude is determined by nonequilibrium constraints. A survey of the macroscopic approach to nonequilibrium states is given in the paper ''Nonequilibrium States and Long Range Correlations in Chemical Dynamics,'' by G. Nicolis et al. However, over the last few years important progress has been made in the simulation of nonequilibrium situations using mainly molecular dynamics. It appears now that processes corresponding to self-organization as well as the appearance of long-range correlations can be obtained in this way starting from a program involving Newtonian dynamics (generally the laws of interaction correspond to hard spheres or hard disks). Examples of such types of studies leading to Benard instabilities, to chemical clocks, or to spatial structure formation are given in this report. As a result, we may now view self-organization as a direct expression of an appropriate microscopic dynamics. This is the reason why we have devoted much work to the study of large Poincare systems (LPS) involving continuous sets of resonances. These systems have been shown to lead, according to the constraints, either to equilibrium situations or to nonequilibrium states involving long range correlations. We discuss LPS in the frame of classical mechanics
Energy Conversion in High Enthalpy Flows and Non-equilibrium Plasmas
2014-01-01
Igor V. Adamovich5, Walter R. Lempert6, and J. William Rich*7 Michael A. Chaszeyka Nonequilibrium Thermodynamics Laboratories, Department of...characterized by significant overpopulation of the higher vibrational quantum levels; in most cases, there are not total population inversions...Uribarri and Ned Allen); and The Michael A. Chaszeyka Gift to the OSU Nonequilibrium Thermodynamics Laboratories. We wish to thank Dr. Graham Candler and
Nonequilibrium flow computations. 1. An analysis of numerical formulations of conservation laws
International Nuclear Information System (INIS)
Liu, Y.; Vinokur, M.
1988-06-01
Modern numerical techniques employing properties of flux Jacobian matrices are extended to general, nonequilibrium flows. Generalizations of the Beam-Warming scheme, Steger-Warming and van Leer Flux-vector splittings, and Roe's approximate Riemann solver are presented for 3-D, time-varying grids. The analysis is based on a thermodynamic model that includes the most general thermal and chemical nonequilibrium flow of an arbitrary gas. Various special cases are also discussed
The composition of corotating energetic particle streams
International Nuclear Information System (INIS)
McGuire, R.E.; von Rosenvinge, T.T.; McDonald, F.B.
1978-01-01
The relative abundances of 1.5--23 MeV per nucleon ions in corotating nucleon streams are compared with ion abundances in particle events associated with solar flares and with solar and solar wind abundances. He/O and C/O ratios are found to be a factor of the order 2--3 greater in corotating streams than in flare-associated events. The distribution of H/He ratios in corotating streams is found to be much narrower and of lower average value than in flare-associated events. H/He in corotating energetic particle streams compares favorably in both lack of variability and numerical value with H/He in high-speed solar wind plasma streams. The lack of variability suggests that the source population for the corotating energetic particles is the solar wind, a suggestion consistent with acceleration of the corotating particles in interplanetary space
Energetic Particle Estimates for Stellar Flares
Youngblood, Allison; Chamberlin, Phil; Woods, Tom
2018-01-01
In the heliosphere, energetic particles are accelerated away from the Sun during solar flares and/or coronal mass ejections where they frequently impact the Earth and other solar system bodies. Solar (or stellar) energetic particles (SEPs) not only affect technological assets, but also influence mass loss and chemistry in planetary atmospheres (e.g., depletion of ozone). SEPs are increasingly recognized as an important factor in assessing exoplanet habitability, but we do not yet have constraints on SEP emission from any stars other than the Sun. Until indirect measurements are available, we must assume solar-like particle production and apply correlations between solar flares and SEPs detected near Earth to stellar flares. We present improved scaling relations between solar far-UV flare flux and >10 MeV proton flux near Earth. We apply these solar scaling relations to far-UV flares from exoplanet host stars and discuss the implications for modeling chemistry and mass loss in exoplanet atmospheres.
Energetics in robotic flight at small scales.
Karydis, Konstantinos; Kumar, Vijay
2017-02-06
Recent advances in design, sensing and control have led to aerial robots that offer great promise in a range of real-world applications. However, one critical open question centres on how to improve the energetic efficiency of aerial robots so that they can be useful in practical situations. This review paper provides a survey on small-scale aerial robots (i.e. less than 1 m 2 area foot print, and less than 3 kg weight) from the point of view of energetics. The paper discusses methods to improve the efficiency of aerial vehicles, and reports on recent findings by the authors and other groups on modelling the impact of aerodynamics for the purpose of building energy-aware motion planners and controllers.
HAWC and Solar Energetic Transient Events
Lara, A.; Ryan, J. M.
2013-12-01
The High Altitude Water Cherenkov (HAWC) observatory is being constructed at the volcano Sierra Negra (4100 m a.s.l.) in Mexico. HAWC's primary purpose is the study of both galactic and extra-galactic sources of high energy gamma rays. The HAWC instrument will consist of 300 large water Cherenkov detectors whose counting rate will be sensitive to cosmic rays with energies above the geomagnetic cutoff of the site ( ˜ 8 GV). In particular, HAWC will detect solar energetic particles known as Ground Level Enhancements (GLEs), and the effect of Coronal Mass Ejections on the galactic cosmic rays, known as Forbush Decreases (FDs). The Milagro experiment, the HAWC predecessor, successfully observed GLEs and the HAWC engineering array "VAMOS" already observed a FD. HAWC will be sensitive to γ rays and neutrons produced during large solar flares. In this work, we present the instrument and discuss its capability to observe solar energetic events. i. e., flares and CMEs.
Generic considerations of LMFBR hypothetical accident energetics
Energy Technology Data Exchange (ETDEWEB)
Fauske, H.K.; Cho, D.H.; Epstein, M.; Grolmes, M.A.; Henry, R.E.
1978-01-01
The paper provides a preliminary assessment of generic accident energetics issues associated with alternatives relative to the reference (U,Pu) oxide fuel in liquid metal fast breeder reactors. The alternatives considered include thorium- and uranium-based oxide, carbide and metal fuel types. This assessment is made within the context of low probability, but potentially large consequence accidents, e.g., core-disruptive accidents.
Theoretical studies on energetic materials bearing pentaflurosulphyl ...
Indian Academy of Sciences (India)
Theoretical studies on the compounds with SF5 groups. 1167. Table 2. Calculated total energies (E0), zero-point energies (ZPE), densities and heats of formation (HOFs) for the title energetic materials. E0 and ZPE are in a.u., HOFs are in kJ/mol, densities are in g/cm3. Compound. E0. ZPE. Hf, gas. Hf, sub. Hf, solid. Density.
Energetic Issues Concerning the Content of Money
Negoescu Gheorghe; Radu Riana Iren
2012-01-01
In full times of crisis, money has become increasingly more important. We put the issue to analyze whether money can be considered a form of energy. The article is taking into consideration the conservation of energy and for money is due to kinetic energy during the boom and to potential energy during the crisis. In the article is also made an illustration of the energetic content of money at a company’s level.
Stochastic Energetics for Non-Gaussian Processes
Kanazawa, Kiyoshi; Sagawa, Takahiro; Hayakawa, Hisao
2012-05-01
By introducing a new stochastic integral, we investigate the energetics of classical stochastic systems driven by non-Gaussian white noises. In particular, we introduce a decomposition of the total energy difference into the work and the heat for each trajectory, and derive a formula to calculate the heat from experimental data on the dynamics. We apply our formulation and results to a Langevin system driven by a Poisson noise.
Energetic cost of walking in fossil hominins.
Vidal-Cordasco, M; Mateos, A; Zorrilla-Revilla, G; Prado-Nóvoa, O; Rodríguez, J
2017-11-01
Many biomechanical studies consistently show that a broader pelvis increases the reaction forces and bending moments across the femoral shaft, increasing the energetic costs of unloaded locomotion. However, a biomechanical model does not provide the real amount of metabolic energy expended in walking. The aim of this study is to test the influence of pelvis breadth on locomotion cost and to evaluate the locomotion efficiency of extinct Pleistocene hominins. The current study measures in vivo the influence of pelvis width on the caloric cost of locomotion, integrating anthropometry, body composition and indirect calorimetry protocols in a sample of 46 subjects of both sexes. We show that a broader false pelvis is substantially more efficient for locomotion than a narrower one and that the influence of false pelvis width on the energetic cost is similar to the influence of leg length. Two models integrating body mass, femur length and bi-iliac breadth are used to estimate the net and gross energetic costs of locomotion in a number of extinct hominins. The results presented here show that the locomotion of Homo was not energetically more efficient than that of Australopithecus and that the locomotion of extinct Homo species was not less efficient than that of modern Homo sapiens. The changes in the anatomy of the pelvis and lower limb observed with the appearance of Homo ergaster probably did not fully offset the increased expenditure resulting from a larger body mass. Moreover, the narrow pelvis in modern humans does not contribute to greater efficiency of locomotion. © 2017 Wiley Periodicals, Inc.
Development of an inviscid flux scheme for thermochemical nonequilibrium flow
Campbell, Charles Hugh
Solutions to the governing equations that model hypersonic aerothermodynamics rely heavily on the mathematical and numerical technology that characterizes Computational Fluid Dynamics. Many areas of significant investigation are relevant to advancing state of the art hypersonic aerothermodynamic engineering and applied research analyses. Due to the relatively high energy achieved by spacecraft during launch, physical models for thermal nonequilibrium and chemical nonequilibrium are necessary to develop adequate numerical reentry simulations. In addition, complex features of the Navier Stokes equations require sophisticated mathematical and numerical techniques in order to develop reasonably accurate simulations in an acceptable amount of time. The objective of this work is to present the development of a new inviscid flux evaluation method. This new method, referred to as the Flux Consistent scheme, is closely related to the Modified Steger-Warming method. The unique characteristics of this new flux scheme involve an original eigenvalue implementation. This original eigenvalue formulation, however, leads to incorrect flux magnitudes which must be corrected in the total flux to provide an accurate representation of the inviscid fluxes. The mathematical technique used to identify flux magnitude errors in the Flux Consistent scheme is also applied to the Modified Steger-Warming flux evaluation method. This assessment leads to the characterization of flux errors in the Modified Steger-Warming scheme which are generated by eigenvalue differences between the left and right cell interface flow states. These Modified Steger-Warming flux errors are shown to vanish for supersonic conditions. Two hypotheses in reference to the Modified Steger-Warming scheme are proposed. The first is that sonic glitch problems occurring in some Steger-Warming simulations are the result of the flux error vanishing at supersonic conditions. The second hypothesis concerning the Steger
Nuclear energy I, Non-energetic applications
International Nuclear Information System (INIS)
Lartigue G, J.; Navarrete T, M.; Cabrera M, L.; Arandia, P.A.; Arriola S, H.
1986-01-01
The nuclear energy is defined as the energy produced or absorbed in the nuclear reactions, therefore, these are divided in endothermic and exothermic. The exothermic nuclear reactions present more interest from the point of view of its applications and they can show in four main forms: radioactivity (from 0 to 4 MeV/reaction; light nucleus fusion ( ∼ 20 MeV/reaction), heavy nucleus fusion (∼ 200 MeV/reaction) and nucleons annihilation ( ∼ 2000 MeV/reaction). Nowadays only the fission has reached the stage of profitable energetic application, finding the other three forms in research and development. The non-energetic applications of the nuclear energy are characterized by they do not require of prior conversion to another form of energy and they are made through the use of radioisotopes as well as through the use of endothermic reaction caused in particle accelerators. In this work are presented some of the non-energetic applications with its theoretical and experimental basis as well as its benefits of each one. (Author)
Nonadditive Compositional Curvature Energetics of Lipid Bilayers
Sodt, A. J.; Venable, R. M.; Lyman, E.; Pastor, R. W.
2016-09-01
The unique properties of the individual lipids that compose biological membranes together determine the energetics of the surface. The energetics of the surface, in turn, govern the formation of membrane structures and membrane reshaping processes, and thus they will underlie cellular-scale models of viral fusion, vesicle-dependent transport, and lateral organization relevant to signaling. The spontaneous curvature, to the best of our knowledge, is always assumed to be additive. We describe observations from simulations of unexpected nonadditive compositional curvature energetics of two lipids essential to the plasma membrane: sphingomyelin and cholesterol. A model is developed that connects molecular interactions to curvature stress, and which explains the role of local composition. Cholesterol is shown to lower the number of effective Kuhn segments of saturated acyl chains, reducing lateral pressure below the neutral surface of bending and favoring positive curvature. The effect is not observed for unsaturated (flexible) acyl chains. Likewise, hydrogen bonding between sphingomyelin lipids leads to positive curvature, but only at sufficient concentration, below which the lipid prefers negative curvature.
Calculation of the energetics of chemical reactions
Energy Technology Data Exchange (ETDEWEB)
Dunning, T.H. Jr.; Harding, L.B.; Shepard, R.L.; Harrison, R.J.
1988-01-01
To calculate the energetics of chemical reactions we must solve the electronic Schroedinger equation for the molecular conformations of importance for the reactive encounter. Substantial changes occur in the electronic structure of a molecular system as the reaction progresses from reactants through the transition state to products. To describe these changes, our approach includes the following three elements: the use of multiconfiguration self-consistent field wave functions to provide a consistent zero-order description of the electronic structure of the reactants, transition state, and products; the use of configuration interaction techniques to describe electron correlation effects needed to provide quantitative predictions of the reaction energetics; and the use of large, optimized basis sets to provide the flexibility needed to describe the variations in the electronic distributions. With this approach we are able to study reactions involving as many as 5--6 atoms with errors of just a few kcal/mol in the predicted reaction energetics. Predictions to chemical accuracy, i.e., to 1 kcal/mol or less, are not yet feasible, although continuing improvements in both the theoretical methodology and computer technology suggest that this will soon be possible, at least for reactions involving small polyatomic species. 4 figs.
Energetic particle investigation using the ERNE instrument
Directory of Open Access Journals (Sweden)
J. Torsti
1996-05-01
Full Text Available During solar flares and coronal mass ejections, nuclei and electrons accelerated to high energies are injected into interplanetary space. These accelerated particles can be detected at the SOHO satellite by the ERNE instrument. From the data produced by the instrument, it is possible to identify the particles and to calculate their energy and direction of propagation. Depending on variable coronal/interplanetary conditions, different kinds of effects on the energetic particle transport can be predicted. The problems of interest include, for example, the effects of particle properties (mass, charge, energy, and propagation direction on the particle transport, the particle energy changes in the transport process, and the effects the energetic particles have on the solar-wind plasma. The evolution of the distribution function of the energetic particles can be measured with ERNE to a better accuracy than ever before. This gives us the opportunity to contribute significantly to the modeling of interplanetary transport and acceleration. Once the acceleration/transport bias has been removed, the acceleration-site abundance of elements and their isotopes can be studied in detail and compared with spectroscopic observations.
Energetic Particles Dynamics in Mercury's Magnetosphere
Walsh, Brian M.; Ryou, A.S.; Sibeck, D. G.; Alexeev, I. I.
2013-01-01
We investigate the drift paths of energetic particles in Mercury's magnetosphere by tracing their motion through a model magnetic field. Test particle simulations solving the full Lorentz force show a quasi-trapped energetic particle population that gradient and curvature drift around the planet via "Shabansky" orbits, passing though high latitudes in the compressed dayside by equatorial latitudes on the nightside. Due to their large gyroradii, energetic H+ and Na+ ions will typically collide with the planet or the magnetopause and will not be able to complete a full drift orbit. These simulations provide direct comparison for recent spacecraft measurements from MESSENGER. Mercury's offset dipole results in an asymmetric loss cone and therefore an asymmetry in particle precipitation with more particles precipitating in the southern hemisphere. Since the planet lacks an atmosphere, precipitating particles will collide directly with the surface of the planet. The incident charged particles can kick up neutrals from the surface and have implications for the formation of the exosphere and weathering of the surface
Study on penetration-induced initiation of energetic fragment
Qiao, Xiangxin; Xu, Heyang
2017-09-01
In order to investigate penetration-induced initiation of energetic fragment penetrating target, PTFE/Al (mass ratio 73.5/26.5) pressed and sintered into a Ф8mm × 8mm cylinder. To form energetic fragment, the cylinder was put into a closed container made by 35CrMnSiA. The container is 12mm long, 2mm thick. Energetic fragments were launched by a 14.5mm ballistic gun with a series of velocities and the penetrate process was simulated by AUTODYN-3D. The results show that the stress peak of energetic material exceed the initiation threshold, and energetic material will deflagrate, when energetic fragments impact velocity more than 800 m/s. The research results can provide reference for designs of energetic warhead.
International Nuclear Information System (INIS)
Diaz de la Rubia, T.
1989-01-01
The primary state of damage present in a solid as a result of particle irradiation has been a topic of interest to the physics and materials research community over the last forty years. Energetic displacement cascades resulting from the heavy ion irradiation of a solid play a prominent role in radiation damage and non-equilibrium processing of materials; however, their study has been hampered by the small size (∼10 -20 cm 3 ) and short lifetime (∼10 -11 s) as well as by their highly non-homogeneous nature. In this work, the molecular dynamics computer simulation technique is employed to study the structure and dynamics of energetic displacement cascades in Cu and Ni. The atomic interactions in Cu were described with the use of the Gibson II form of the Born-Mayer pair potential while for Ni the Johnson-Erginsoy pair potential was employed. Calculations were also carried out with the use of the embedded atom method many-body potentials. The results provide the first detailed microscopic description of the evolution of the cascade. The author shows for the first time, that a process akin to melting takes place in the core of the cascade. Atomic mixing, point defect production and point defect agglomeration, all processes directly related to the evolution of the cascade, are then explained in terms of a simple model in which the liquid-like nature of the cascade plays a dominant role in determining the primary state of damage
Microstructure of Al2O3 nanocrystalline/cobalt-based alloy composite coatings by laser deposition
International Nuclear Information System (INIS)
Li Mingxi; He Yizhu; Yuan Xiaomin; Zhang Shihong
2006-01-01
Composite coatings, made of nano-Al 2 O 3 /cobalt-based alloy, produced by a 5-kW CO 2 laser on Ni-based superalloy were investigated. The coatings were examined to reveal their microstructure using optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffraction instrument. The results showed that some equilibrium or non-equilibrium phases, such as γ-Co, Cr 23 C 6 , CoAl 2 O 4 , Al 2 O 3 and ε-Co existed in the coatings. Fine and short dendritic microstructure and columnar to equiaxed transition occurred by adding nano-Al 2 O 3 particle. With the increase of nano-materials (1%, mass fraction), fully equiaxed crystallization appeared. These were contributed to that nano-Al 2 O 3 particles acted as new nucleation site and rapid solidification of the melted pool. The results also showed inhomogeneous dispersion of nano-Al 2 O 3 that resulted in the formation of ε-Co phase in the coatings. The sub-microstructure of the clad was stacking fault. The mechanism of formation of equiaxed grains was also analyzed
A theory of nonequilibrium steady states in quantum chaotic systems
Wang, Pei
2017-09-01
Nonequilibrium steady state (NESS) is a quasistationary state, in which exist currents that continuously produce entropy, but the local observables are stationary everywhere. We propose a theory of NESS under the framework of quantum chaos. In an isolated quantum system whose density matrix follows a unitary evolution, there exist initial states for which the thermodynamic limit and the long-time limit are noncommutative. The density matrix \\hat ρ of these states displays a universal structure. Suppose that \\renewcommand{\\ket}[1]{{\\vert #1 >}} \\ketα and \\renewcommand{\\ket}[1]{{\\vert #1 >}} \\ketβ are different eigenstates of the Hamiltonian with energies E_α and E_β , respectively. \\renewcommand{\\bra}[1]{} \\braα\\hat ρ \\ketβ behaves as a random number which has zero mean. In thermodynamic limit, the variance of \\renewcommand{\\bra}[1]{} \\braα\\hat ρ \\ketβ is a smooth function of ≤ft\\vert E_α-E_β\\right\\vert , scaling as 1/≤ft\\vert E_α-E_β\\right\\vert 2 in the limit ≤ft\\vert E_α-E_β\\right\\vert \\to 0 . If and only if this scaling law is obeyed, the initial state evolves into NESS in the long time limit. We present numerical evidence of our hypothesis in a few chaotic models. Furthermore, we find that our hypothesis indicates the eigenstate thermalization hypothesis (ETH) for current operators in a bipartite system.
Nonequilibrium statistical field theory for classical particles: Basic kinetic theory.
Viermann, Celia; Fabis, Felix; Kozlikin, Elena; Lilow, Robert; Bartelmann, Matthias
2015-06-01
Recently Mazenko and Das and Mazenko [Phys. Rev. E 81, 061102 (2010); J. Stat. Phys. 149, 643 (2012); J. Stat. Phys. 152, 159 (2013); Phys. Rev. E 83, 041125 (2011)] introduced a nonequilibrium field-theoretical approach to describe the statistical properties of a classical particle ensemble starting from the microscopic equations of motion of each individual particle. We use this theory to investigate the transition from those microscopic degrees of freedom to the evolution equations of the macroscopic observables of the ensemble. For the free theory, we recover the continuity and Jeans equations of a collisionless gas. For a theory containing two-particle interactions in a canonical perturbation series, we find the macroscopic evolution equations to be described by the Born-Bogoliubov-Green-Kirkwood-Yvon hierarchy with a truncation criterion depending on the order in perturbation theory. This establishes a direct link between the classical and the field-theoretical approaches to kinetic theory that might serve as a starting point to investigate kinetic theory beyond the classical limits.
A calculational scheme for nonequilibrium quantum field system
International Nuclear Information System (INIS)
Yamanaka, Y.
1991-01-01
A new calculational scheme is presented for interacting nonequi-librium time dependent quantum field systems within the framework of thermo field dynamics (TFD), taking account of the fact that the thermal vacuum should go through many inequivalent state vector spaces. A para-meter parametrizing various state vector spaces has to be introduced and plays a role of new time-variable. Thus we have double-time TFD. The 2 requirements in this double-time TFD are imposed to establish a quasi-particle picture to get an attainable scheme of perturbative calculation : the existence of the spectral representation for the full propagator and the diagonalization of the quasi-particle Hamiltonian. The 1st condition turns out to amount to the existence of local-time tempera-ture. The 2nd condition leads to the master equation for the number density. This formalism is applied to high-energy heavy ion collision process. The very fundamental question is then how the thermodynamical properties such as heat and temperature appear in such an isolated system. This double-time TFD, suitable for isolated thermal systems of quantum fields, can handle the situation from the beginning of the process. (author). 24 refs.; 1 fig
The Coronal Monsoon: Thermal Nonequilibrium Revealed by Periodic Coronal Rain
Auchère, Frédéric; Froment, Clara; Soubrié, Elie; Antolin, Patrick; Oliver, Ramon; Pelouze, Gabriel
2018-02-01
We report on the discovery of periodic coronal rain in an off-limb sequence of Solar Dynamics Observatory/Atmospheric Imaging Assembly images. The showers are co-spatial and in phase with periodic (6.6 hr) intensity pulsations of coronal loops of the sort described by Auchère et al. and Froment et al. These new observations make possible a unified description of both phenomena. Coronal rain and periodic intensity pulsations of loops are two manifestations of the same physical process: evaporation/condensation cycles resulting from a state of thermal nonequilibrium. The fluctuations around coronal temperatures produce the intensity pulsations of loops, and rain falls along their legs if thermal runaway cools the periodic condensations down and below transition-region temperatures. This scenario is in line with the predictions of numerical models of quasi-steadily and footpoint heated loops. The presence of coronal rain—albeit non-periodic—in several other structures within the studied field of view implies that this type of heating is at play on a large scale.
Ising game: Nonequilibrium steady states of resource-allocation systems
Xin, C.; Yang, G.; Huang, J. P.
2017-04-01
Resource-allocation systems are ubiquitous in the human society. But how external fields affect the state of such systems remains poorly explored due to the lack of a suitable model. Because the behavior of spins pursuing energy minimization required by physical laws is similar to that of humans chasing payoff maximization studied in game theory, here we combine the Ising model with the market-directed resource-allocation game, yielding an Ising game. Based on the Ising game, we show theoretical, simulative and experimental evidences for a formula, which offers a clear expression of nonequilibrium steady states (NESSs). Interestingly, the formula also reveals a convertible relationship between the external field (exogenous factor) and resource ratio (endogenous factor), and a class of saturation as the external field exceeds certain limits. This work suggests that the Ising game could be a suitable model for studying external-field effects on resource-allocation systems, and it could provide guidance both for seeking more relations between NESSs and equilibrium states and for regulating human systems by choosing NESSs appropriately.
Foundations of modelling of nonequilibrium low-temperature plasmas
Alves, L. L.; Bogaerts, A.; Guerra, V.; Turner, M. M.
2018-02-01
This work explains the need for plasma models, introduces arguments for choosing the type of model that better fits the purpose of each study, and presents the basics of the most common nonequilibrium low-temperature plasma models and the information available from each one, along with an extensive list of references for complementary in-depth reading. The paper presents the following models, organised according to the level of multi-dimensional description of the plasma: kinetic models, based on either a statistical particle-in-cell/Monte-Carlo approach or the solution to the Boltzmann equation (in the latter case, special focus is given to the description of the electron kinetics); multi-fluid models, based on the solution to the hydrodynamic equations; global (spatially-average) models, based on the solution to the particle and energy rate-balance equations for the main plasma species, usually including a very complete reaction chemistry; mesoscopic models for plasma–surface interaction, adopting either a deterministic approach or a stochastic dynamical Monte-Carlo approach. For each plasma model, the paper puts forward the physics context, introduces the fundamental equations, presents advantages and limitations, also from a numerical perspective, and illustrates its application with some examples. Whenever pertinent, the interconnection between models is also discussed, in view of multi-scale hybrid approaches.
Nonequilibrium Green's function method for quantum thermal transport
Wang, Jian-Sheng; Agarwalla, Bijay Kumar; Li, Huanan; Thingna, Juzar
2014-12-01
This review deals with the nonequilibrium Green's function (NEGF) method applied to the problems of energy transport due to atomic vibrations (phonons), primarily for small junction systems. We present a pedagogical introduction to the subject, deriving some of the well-known results such as the Laudauer-like formula for heat current in ballistic systems. The main aim of the review is to build the machinery of the method so that it can be applied to other situations, which are not directly treated here. In addition to the above, we consider a number of applications of NEGF, not in routine model system calculations, but in a few new aspects showing the power and usefulness of the formalism. In particular, we discuss the problems of multiple leads, coupled left-right-lead system, and system without a center. We also apply the method to the problem of full counting statistics. In the case of nonlinear systems, we make general comments on the thermal expansion effect, phonon relaxation time, and a certain class of mean-field approximations. Lastly, we examine the relationship between NEGF, reduced density matrix, and master equation approaches to thermal transport.
Primordial quantum nonequilibrium and large-scale cosmic anomalies
Colin, Samuel; Valentini, Antony
2015-08-01
We study incomplete relaxation to quantum equilibrium at long wavelengths, during a preinflationary phase, as a possible explanation for the reported large-scale anomalies in the cosmic microwave background. Our scenario makes use of the de Broglie-Bohm pilot-wave formulation of quantum theory, in which the Born probability rule has a dynamical origin. The large-scale power deficit could arise from incomplete relaxation for the amplitudes of the primordial perturbations. We show, by numerical simulations for a spectator scalar field, that if the preinflationary era is radiation dominated then the deficit in the emerging power spectrum will have a characteristic shape (an inverse-tangent dependence on wave number k , with oscillations). It is found that our scenario is able to produce a power deficit in the observed region and of the observed (approximate) magnitude for an appropriate choice of cosmological parameters. We also discuss the large-scale anisotropy, which might arise from incomplete relaxation for the phases of the primordial perturbations. We present numerical simulations for phase relaxation, and we show how to define characteristic scales for amplitude and phase nonequilibrium. The extent to which the data might support our scenario is left as a question for future work. Our results suggest that we have a potentially viable model that might explain two apparently independent cosmic anomalies by means of a single mechanism.
Nonequilibrium dynamics of probe filaments in actin-myosin networks
Gladrow, J.; Broedersz, C. P.; Schmidt, C. F.
2017-08-01
Active dynamic processes of cells are largely driven by the cytoskeleton, a complex and adaptable semiflexible polymer network, motorized by mechanoenzymes. Small dimensions, confined geometries, and hierarchical structures make it challenging to probe dynamics and mechanical response of such networks. Embedded semiflexible probe polymers can serve as nonperturbing multiscale probes to detect force distributions in active polymer networks. We show here that motor-induced forces transmitted to the probe polymers are reflected in nonequilibrium bending dynamics, which we analyze in terms of spatial eigenmodes of an elastic beam under steady-state conditions. We demonstrate how these active forces induce correlations among the mode amplitudes, which furthermore break time-reversal symmetry. This leads to a breaking of detailed balance in this mode space. We derive analytical predictions for the magnitude of resulting probability currents in mode space in the white-noise limit of motor activity. We relate the structure of these currents to the spatial profile of motor-induced forces along the probe polymers and provide a general relation for observable currents on two-dimensional hyperplanes.
Non-equilibrium phenomena near vapor-liquid interfaces
Energy Technology Data Exchange (ETDEWEB)
Kryukov, Alexei; Levashov, Vladimir; Puzina, Yulia [Moscow Power Engineering Institute, Moscow (Russian Federation)
2013-08-01
Written by experts in the field. This book presents information on the development of a non-equilibrium approach to the study of heat and mass transfer problems using vapor-liquid interfaces, and demonstrates its application to a broad range of problems. In the process, the following peculiarities become apparent: 1. At vapor condensation on the interface from gas-vapor mixture, non-condensable components can lock up the interface surface and condensation stops completely. 2. At the evolution of vapor film on the heater in superfluid helium (He-II), the boiling mass flux density from the vapor-liquid interface is effectively zero at the macroscopic scale. 3. In problems concerning the motion of He-II bridges inside capillaries filled by vapor, in the presence of axial heat flux the He-II bridge cannot move from the heater as would a traditional liquid, but in the opposite direction instead. Thus the heater attracts the superfluid helium bridge. 4. The shape of liquid-vapor interface at film boiling on the axis-symmetric heaters immersed in liquid greatly depends on heat flux in the interface. Thus a new type of hydrostatic problems appears when in contrast to traditional statements the shape of the liquid-vapor interface has a complex profile with a point of inflection and a smooth exit on a free liquid surface.
Controlling competing electronic orders via non-equilibrium acoustic phonons
Schuett, Michael; Orth, Peter; Levchenko, Alex; Fernandes, Rafael
The interplay between multiple electronic orders is a hallmark of strongly correlated systems displaying unconventional superconductivity. While doping, pressure, and magnetic field are the standard knobs employed to assess these different phases, ultrafast pump-and-probe techniques opened a new window to probe these systems. Recent examples include the ultrafast excitation of coherent optical phonons coupling to electronic states in cuprates and iron pnictides. In this work, we demonstrate theoretically that non-equilibrium acoustic phonons provide a promising framework to manipulate competing electronic phases and favor unconventional superconductivity over other states. In particular, we show that electrons coupled to out-of-equilibrium anisotropic acoustic phonons enter a steady state in which the effective electronic temperature varies around the Fermi surface. Such a momentum-dependent temperature can then be used to selectively heat electronic states that contribute primarily to density-wave instabilities, reducing their competition with superconductivity. We illustrate this phenomenon by computing the microscopic steady-state phase diagram of the iron pnictides, showing that superconductivity is enhanced with respect to the competing antiferromagnetic phase.
Role of conviction in nonequilibrium models of opinion formation.
Crokidakis, Nuno; Anteneodo, Celia
2012-12-01
We analyze the critical behavior of a class of discrete opinion models in the presence of disorder. Within this class, each agent opinion takes a discrete value (± 1 or 0) and its time evolution is ruled by two terms, one representing agent-agent interactions and the other the degree of conviction or persuasion (a self-interaction). The mean-field limit, where each agent can interact evenly with any other, is considered. Disorder is introduced in the strength of both interactions, with either quenched or annealed random variables. With probability p (1-p), a pairwise interaction reflects a negative (positive) coupling, while the degree of conviction also follows a binary probability distribution (two different discrete probability distributions are considered). Numerical simulations show that a nonequilibrium continuous phase transition, from a disordered state to a state with a prevailing opinion, occurs at a critical point p(c) that depends on the distribution of the convictions, with the transition being spoiled in some cases. We also show how the critical line, for each model, is affected by the update scheme (either parallel or sequential) as well as by the kind of disorder (either quenched or annealed).
Nonequilibrium thermodynamic models and applications to hydrogen plasma
International Nuclear Information System (INIS)
Cho, K.Y.
1988-01-01
A generalized multithermal equilibrium (GMTE) thermodynamic model is developed and presented with applications to hydrogen. A new chemical equilibrium equation for GMTE is obtained without the ensemble temperature concept, used by a previous MTE model. The effects of the GMTE model on the derivation and calculation of the thermodynamic, transport, and radiative properties are presented and significant differences from local thermal equilibrium (LTE) and two temperature model are discussed. When the electron translational temperature (T e ) is higher than the translational temperature of the heavy particles, the effects of hydrogen molecular species to the properties are significant at high T e compared with LTE results. The density variations of minor species are orders of magnitude with kinetic nonequilibrium at a constant electron temperature. A collisional-radiative model is also developed with the GMTE chemical equilibrium equation to study the effects of radiative transfer and the ambipolar diffusion on the population distribution of the excited atoms. The nonlocal radiative transfer effect is parameterized by an absorption factor, which is defined as a ratio of the absorbed intensity to the spontaneous emission coefficient
Bibliography on Small Systems: Nonequilibrium Phenomena and Anomalous Behavior
LIU, Fei; Lamberto, Rondoni; TANG, Lei-Han; ZHOU, Hai-Jun; WANG, Yan-Ting
2014-10-01
The workshop and satellite conference held in July 2013 at the Kavli Institute for Theoretical Physics China (KITPC) of the Chinese Academy of Sciences (CAS) brought together experts of a variety of different fields, and constituted a unique opportunity to share ideas and breed new ones in a strongly interdisciplinary fashion. At the same time, the breadth of the scope of these two meetings was so wide that the need for a collection of reference books and papers was pointed out, in order to help the interested professionals, as well as graduate students, both to tackle the technically advanced issues and to bridge the gaps, necessarily present in each other's background. Therefore, we invited some of the participants to produce a bibliography containing the most relevant works in their own fields, and to complement this bibliography with a short explanation of the content of those books and papers. We are thus very grateful to Igor Goychuk, David Lacoste, Annick Lesne, Andrea Puglisi, Hong Qian and Hugo Touchette for having accepted our invitation and for having produced what we consider a very useful tool for all those who want to learn or to understand more deeply the current theories concerning small and nonequilibrium systems.
Calculating zeros: Non-equilibrium free energy calculations
International Nuclear Information System (INIS)
Oostenbrink, Chris; Gunsteren, Wilfred F. van
2006-01-01
Free energy calculations on three model processes with theoretically known free energy changes have been performed using short simulation times. A comparison between equilibrium (thermodynamic integration) and non-equilibrium (fast growth) methods has been made in order to assess the accuracy and precision of these methods. The three processes have been chosen to represent processes often observed in biomolecular free energy calculations. They involve a redistribution of charges, the creation and annihilation of neutral particles and conformational changes. At very short overall simulation times, the thermodynamic integration approach using discrete steps is most accurate. More importantly, reasonable accuracy can be obtained using this method which seems independent of the overall simulation time. In cases where slow conformational changes play a role, fast growth simulations might have an advantage over discrete thermodynamic integration where sufficient sampling needs to be obtained at every λ-point, but only if the initial conformations do properly represent an equilibrium ensemble. From these three test cases practical lessons can be learned that will be applicable to biomolecular free energy calculations
Enforcing conservation laws in nonequilibrium cluster perturbation theory
Gramsch, Christian; Potthoff, Michael
2017-05-01
Using the recently introduced time-local formulation of the nonequilibrium cluster perturbation theory (CPT), we construct a generalization of the approach such that macroscopic conservation laws are respected. This is achieved by exploiting the freedom for the choice of the starting point of the all-order perturbation theory in the intercluster hopping. The proposed conserving CPT is a self-consistent propagation scheme which respects the conservation of energy, particle number, and spin, which treats short-range correlations exactly up to the linear scale of the cluster, and which represents a mean-field-like approach on length scales beyond the cluster size. Using Green's functions, conservation laws are formulated as local constraints on the local spin-dependent particle and the doublon density. We consider them as conditional equations to self-consistently fix the time-dependent intracluster one-particle parameters. Thanks to the intrinsic causality of the CPT, this can be set up as a step-by-step time propagation scheme with a computational effort scaling linearly with the maximum propagation time and exponentially in the cluster size. As a proof of concept, we consider the dynamics of the two-dimensional, particle-hole-symmetric Hubbard model following a weak interaction quench by simply employing two-site clusters only. Conservation laws are satisfied by construction. We demonstrate that enforcing them has strong impact on the dynamics. While the doublon density is strongly oscillating within plain CPT, a monotonic relaxation is observed within the conserving CPT.
Geometry and symmetry in non-equilibrium thermodynamic systems
Sonnino, Giorgio
2017-06-01
The ultimate aim of this series of works is to establish the closure equations, valid for thermodynamic systems out from the Onsager region, and to describe the geometry and symmetry in thermodynamic systems far from equilibrium. Geometry of a non-equilibrium thermodynamic system is constructed by taking into account the second law of thermodynamics and by imposing the validity of the Glansdorff-Prigogine Universal Criterion of Evolution. These two constraints allow introducing the metrics and the affine connection of the Space of the Thermodynamic Forces, respectively. The Lie group associated to the nonlinear Thermodynamic Coordinate Transformations (TCT) leaving invariant both the entropy production σ and the Glansdorff-Prigogine dissipative quantity P, is also described. The invariance under TCT leads to the formulation of the Thermodynamic Covariance Principle (TCP): The nonlinear closure equations, i.e. the flux-force relations, must be covariant under TCT. In other terms, the fundamental laws of thermodynamics should be manifestly covariant under transformations between the admissible thermodynamic forces (i.e. under TCT). The symmetry properties of a physical system are intimately related to the conservation laws characterizing the thermodynamic system. Noether's theorem gives a precise description of this relation. The macroscopic theory for closure relations, based on this geometrical description and subject to the TCP, is referred to as the Thermodynamic Field Theory (TFT). This theory ensures the validity of the fundamental theorems for systems far from equilibrium.
Non-Equilibrium Water-Glassy Polymer Dynamics
Davis, Eric; Minelli, Matteo; Baschetti, Marco; Sarti, Giulio; Elabd, Yossef
2012-02-01
For many applications (e.g., medical implants, packaging), an accurate assessment and fundamental understanding of the dynamics of water-glassy polymer interactions is of great interest. In this study, sorption and diffusion of pure water in several glassy polymers films, such as poly(styrene) (PS), poly(methyl methacrylate) (PMMA), poly(lactide) (PLA), were measured over a wide range of vapor activities and temperatures using several experimental techniques, including quartz spring microbalance (QSM), quartz crystal microbalance (QCM), and time-resolved Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy. Non-Fickian behavior (diffusion-relaxation phenomena) was observed by all three techniques, while FTIR-ATR spectroscopy also provides information about the distribution of the states of water and water transport mechanisms on a molecular-level. Specifically, the states of water are significantly different in PS compared to PMMA and PLA. Additionally, a purely predictive non-equilibrium lattice fluid (NELF) model was applied to predict the sorption isotherms of water in these glassy polymers.
Nonequilibrium atmospheric secondary organic aerosol formation and growth.
Perraud, Véronique; Bruns, Emily A; Ezell, Michael J; Johnson, Stanley N; Yu, Yong; Alexander, M Lizabeth; Zelenyuk, Alla; Imre, Dan; Chang, Wayne L; Dabdub, Donald; Pankow, James F; Finlayson-Pitts, Barbara J
2012-02-21
Airborne particles play critical roles in air quality, health effects, visibility, and climate. Secondary organic aerosols (SOA) formed from oxidation of organic gases such as α-pinene account for a significant portion of total airborne particle mass. Current atmospheric models typically incorporate the assumption that SOA mass is a liquid into which semivolatile organic compounds undergo instantaneous equilibrium partitioning to grow the particles into the size range important for light scattering and cloud condensation nuclei activity. We report studies of particles from the oxidation of α-pinene by ozone and NO(3) radicals at room temperature. SOA is primarily formed from low-volatility ozonolysis products, with a small contribution from higher volatility organic nitrates from the NO(3) reaction. Contrary to expectations, the particulate nitrate concentration is not consistent with equilibrium partitioning between the gas phase and a liquid particle. Rather the fraction of organic nitrates in the particles is only explained by irreversible, kinetically determined uptake of the nitrates on existing particles, with an uptake coefficient that is 1.6% of that for the ozonolysis products. If the nonequilibrium particle formation and growth observed in this atmospherically important system is a general phenomenon in the atmosphere, aerosol models may need to be reformulated. The reformulation of aerosol models could impact the predicted evolution of SOA in the atmosphere both outdoors and indoors, its role in heterogeneous chemistry, its projected impacts on air quality, visibility, and climate, and hence the development of reliable control strategies.
Non-equilibrium statistical thermodynamics of neutron gas in reactor
International Nuclear Information System (INIS)
Hayasaka, Hideo
1977-01-01
The thermodynamic structures of non-equilibrium steady states of highly rarefied neutron gas in various media are considered for the irreversible processes owing to creative and destructive reactions of neutrons with nuclei of these media and supply from the external sources. Under the so-called clean and cold condition in reactor, the medium is regarded virtually as offering the different chemical potential fields for each subsystem of a steady neutron gas system. The fluctuations around a steady state are considered in a Markovian-Gaussian process. The generalized Einstein relations are derived for stationary neutron gas systems. The forces and flows of neutron gases in a medium are defined upon the general stationary solution of the Fokker-Planck equation. There exist the symmetry of the kinetic coefficients, and the minimum entropy production upon neutron-nuclear reactions. The distribution functions in various media are determined by each corresponding extremum condition under the vanishing of changes of the respective total entropies in the Gibbs equation. (auth.)
Non-Equilibrium Properties from Equilibrium Free Energy Calculations
Pohorille, Andrew; Wilson, Michael A.
2012-01-01
Calculating free energy in computer simulations is of central importance in statistical mechanics of condensed media and its applications to chemistry and biology not only because it is the most comprehensive and informative quantity that characterizes the eqUilibrium state, but also because it often provides an efficient route to access dynamic and kinetic properties of a system. Most of applications of equilibrium free energy calculations to non-equilibrium processes rely on a description in which a molecule or an ion diffuses in the potential of mean force. In general case this description is a simplification, but it might be satisfactorily accurate in many instances of practical interest. This hypothesis has been tested in the example of the electrodiffusion equation . Conductance of model ion channels has been calculated directly through counting the number of ion crossing events observed during long molecular dynamics simulations and has been compared with the conductance obtained from solving the generalized Nernst-Plank equation. It has been shown that under relatively modest conditions the agreement between these two approaches is excellent, thus demonstrating the assumptions underlying the diffusion equation are fulfilled. Under these conditions the electrodiffusion equation provides an efficient approach to calculating the full voltage-current dependence routinely measured in electrophysiological experiments.
Controlling Non-Equilibrium Structure Formation on the Nanoscale.
Buchmann, Benedikt; Hecht, Fabian Manfred; Pernpeintner, Carla; Lohmueller, Theobald; Bausch, Andreas R
2017-12-06
Controlling the structure formation of gold nanoparticle aggregates is a promising approach towards novel applications in many fields, ranging from (bio)sensing to (bio)imaging to medical diagnostics and therapeutics. To steer structure formation, the DNA-DNA interactions of DNA strands that are coated on the surface of the particles have become a valuable tool to achieve precise control over the interparticle potentials. In equilibrium approaches, this technique is commonly used to study particle crystallization and ligand binding. However, regulating the structural growth processes from the nano- to the micro- and mesoscale remains elusive. Here, we show that the non-equilibrium structure formation of gold nanoparticles can be stirred in a binary heterocoagulation process to generate nanoparticle clusters of different sizes. The gold nanoparticles are coated with sticky single stranded DNA and mixed at different stoichiometries and sizes. This not only allows for structural control but also yields access to the optical properties of the nanoparticle suspensions. As a result, we were able to reliably control the kinetic structure formation process to produce cluster sizes between tens of nanometers up to micrometers. Consequently, the intricate optical properties of the gold nanoparticles could be utilized to control the maximum of the nanoparticle suspension extinction spectra between 525 nm and 600 nm. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Nonequilibrium forces between neutral atoms mediated by a quantum field
International Nuclear Information System (INIS)
Behunin, Ryan O.; Hu, Bei-Lok
2010-01-01
We study forces between two neutral atoms, modeled as three-dimensional harmonic oscillators, arising from mutual influences mediated by an electromagnetic field but not from their direct interactions. We allow as dynamical variables the center-of-mass motion of the atom, its internal degrees of freedom, and the quantum field treated relativistically. We adopt the method of nonequilibrium quantum field theory which can provide a first-principles, systematic, and unified description including the intrinsic and induced dipole fluctuations. The inclusion of self-consistent back-actions makes possible a fully dynamical description of these forces valid for general atom motion. In thermal equilibrium we recover the known forces--London, van der Waals, and Casimir-Polder--between neutral atoms in the long-time limit. We also reproduce a recently reported force between atoms when the system is out of thermal equilibrium at late times. More noteworthy is the discovery of the existence of a type of (or identification of the source of some known) interatomic force which we call the ''entanglement force,'' originating from the quantum correlations of the internal degrees of freedom of entangled atoms.
A multifluid model extended for strong temperature nonequilibrium
Energy Technology Data Exchange (ETDEWEB)
Chang, Chong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-08-08
We present a multifluid model in which the material temperature is strongly affected by the degree of segregation of each material. In order to track temperatures of segregated form and mixed form of the same material, they are defined as different materials with their own energy. This extension makes it necessary to extend multifluid models to the case in which each form is defined as a separate material. Statistical variations associated with the morphology of the mixture have to be simplified. Simplifications introduced include combining all molecularly mixed species into a single composite material, which is treated as another segregated material. Relative motion within the composite material, diffusion, is represented by material velocity of each component in the composite material. Compression work, momentum and energy exchange, virtual mass forces, and dissipation of the unresolved kinetic energy have been generalized to the heterogeneous mixture in temperature nonequilibrium. The present model can be further simplified by combining all mixed forms of materials into a composite material. Molecular diffusion in this case is modeled by the Stefan-Maxwell equations.
Scantlebury, David M; Mills, Michael G L; Wilson, Rory P; Wilson, John W; Mills, Margaret E J; Durant, Sarah M; Bennett, Nigel C; Bradford, Peter; Marks, Nikki J; Speakman, John R
2014-10-03
Population viability is driven by individual survival, which in turn depends on individuals balancing energy budgets. As carnivores may function close to maximum sustained power outputs, decreased food availability or increased activity may render some populations energetically vulnerable. Prey theft may compromise energetic budgets of mesopredators, such as cheetahs and wild dogs, which are susceptible to competition from larger carnivores. We show that daily energy expenditure (DEE) of cheetahs was similar to size-based predictions and positively related to distance traveled. Theft at 25% only requires cheetahs to hunt for an extra 1.1 hour per day, increasing DEE by just 12%. Therefore, not all mesopredators are energetically constrained by direct competition. Other factors that increase DEE, such as those that increase travel, may be more important for population viability. Copyright © 2014, American Association for the Advancement of Science.
Yan, YiChao; Shi, Wei; Jiang, HongChuan; Xiong, Jie; Zhang, WanLi; Li, Yanrong
2015-12-01
The energetic igniters through integrating Al/NiO nanolaminates on Cr film bridges have been investigated in this study. The microstructures demonstrate well-defined geometry and sharp interfaces. The depth profiles of the X-ray photoelectron spectroscopy of Al/NiO nanolaminates annealed at 550 °C with a bilayer thickness of 250 nm show that the interdiffusion between the Al layer and NiO layer has happened and the annealing temperature cannot provide enough energy to make the diffusion process much more complete. The electrical explosion characteristics employing a capacitor discharge firing set at the optimized charging voltage of 40 V show that the flame duration time is about 700 μs, and an excellent explosion performance is obtained for (Al/NiO)n/Cr igniters with a bilayer thickness of 1000 nm.
Jet quenching and gluon to hadron fragmentation function in non-equilibrium QCD at RHIC and LHC
International Nuclear Information System (INIS)
Nayak, G.C.
2017-01-01
Theoretical understanding of the observed jet quenching measurements at RHIC and LHC is challenging in QCD because it requires understanding of parton to hadron fragmentation function in non-equilibrium QCD. In this paper, by using closed-time path integral formalism, we derive the gauge invariant definition of the gluon to hadron fragmentation function in non-equilibrium QCD which is consistent with factorization theorem in non-equilibrium QCD from first principles.
2013-01-01
This book offers a comprehensive picture of nonequilibrium phenomena in nanoscale systems. Written by internationally recognized experts in the field, this book strikes a balance between theory and experiment, and includes in-depth introductions to nonequilibrium fluctuation relations, nonlinear dynamics and transport, single molecule experiments, and molecular diffusion in nanopores. The authors explore the application of these concepts to nano- and biosystems by cross-linking key methods and ideas from nonequilibrium statistical physics, thermodynamics, stochastic theory, and dynamical s
Effects of the primary recoil spectrum on microstructural evolution
International Nuclear Information System (INIS)
Wiedersich, H.
1989-11-01
For quantitative predictions and comparisons of microstructures that evolve during exposure to different radiation environments at elevated temperature one needs to develop methods that go beyond those based on the number of displacements per atom. The number of freely migrating defects that contribute to the microstructural development is far less than the total number of defects produced, as has been recognized for some time from measurements of radiation-induced segregation and of radiation-enhanced diffusion. One major reason for the small amount of defects available for long range migration is the high concentration and close spatial correlation of vacancies and, to a somewhat lesser degree, of interstitials in cascades produced by high energy knock-ons. As a consequence, many defects either recombine or form immobile defect clusters during the defect formation and cooling phases of the cascades. After doses exceeding a few tenths of a displacement per atom, the residue of small clusters and dislocation loops of vacancy type remaining in the central portions of energetic cascades and subscascades, is the second major reason for the reduction of the mean free path of defects between creation and annihilation. Defect production in various neutron and ion irradiation environments is discussed in light of these facts. A method to calculate the fraction of freely migrating defects from the cluster size distribution of defects produced in cascades is suggested. The results are in good agreement with available data. 22 refs., 5 figs
Ogawa, K.; Isobe, M.; Kawase, H.; Nishitani, T.; Seki, R.; Osakabe, M.; LHD Experiment Group
2018-04-01
A deuterium experiment was initiated to achieve higher-temperature and higher-density plasmas in March 2017 in the Large Helical Device (LHD). The central ion temperature notably increases compared with that in hydrogen experiments. However, an energetic particle mode called the helically-trapped energetic-ion-driven resistive interchange (EIC) mode is often excited by intensive perpendicular neutral beam injections on high ion-temperature discharges. The mode leads to significant decrease of the ion temperature or to limiting the sustainment of the high ion-temperature state. To understand the effect of EIC on the energetic ion confinement, the radial transport of energetic ions is studied by means of the neutron flux monitor and vertical neutron camera newly installed on the LHD. Decreases of the line-integrated neutron profile in core channels show that helically-trapped energetic ions are lost from the plasma.
Solar Energetic Particle Studies with PAMELA
Bravar, U.; Christian, E. R.; deNolfo, Georgia; Ryan, J. M.; Stochaj, S.
2011-01-01
The origin of the high-energy solar energetic particles (SEPs) may conceivably be found in composition signatures that reflect the elemental abundances of the low corona and chromosphere vs. the high corona and solar wind. The presence of secondaries, such as neutrons and positrons, could indicate a low coronal origin of these particles. Velocity dispersion of different species and over a wide energy range can be used to determine energetic particle release times at the Sun. Together with multi-wavelength imaging, in- situ observations of a variety of species, and coverage over a wide energy range provide a critical tool in identifying the origin of SEPs, understanding the evolution of these events within the context of solar active regions, and constraining the acceleration mechanisms at play. The Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA)instrument, successfully launched in 2006 and expected to remain operational until at least the beginning of 2012, measures energetic particles in the same energy range as ground-based neutron monitors, and lower energies as well. It thus bridges the gap between low energy in-situ observations and ground-based Ground Level Enhancements (GLE) observations. It can measure the charge (up to Z=6) and atomic number of the detected particles, and it can identify and measure positrons and detect neutrons-an unprecedented array of data channels that we can bring to bear on the origin of high-energy SEPs. We present prelimiary results on the for the 2006 December 13 solar flare and GLE and the 2011 March 21 solar flare, both registering proton and helium enhancements in PAMELA. Together with multi- spacecraft contextual data and modeling, we discuss the PAMELA results in the context of the different acceleration mechanisms at play.
Vlad; Ross; Schneider
2000-08-01
A characteristic functional approach is suggested for Levy diffusion in disordered systems with external force fields. We study the overdamped motion of an ensemble of independent particles and assume that the force acting upon one particle is made up of two additive components: a linear term generated by a harmonic potential and a second term generated by the interaction with the disordered system. The stochastic properties of the second term are evaluated by using Huber's approach to complex relaxation [Phys. Rev. B 31, 6070 (1985)]. We assume that the interaction between a moving particle and the environment can be expressed by the contribution of a large number of relaxation channels, each channel having a very small probability of being open and obeying Poisson statistics. Two types of processes are investigated: (a) Levy diffusion with static disorder for which the fluctuations of the random force are frozen and last forever and (b) diffusion with strong dynamic disorder and independent Levy fluctuations (Levy white noise). In both cases we show that the probability distribution of the position of a diffusing particle tends towards a stationary nonequilibrium form. The characteristic functional of concentration fluctuations is evaluated in both cases by using the theory of random point processes. For large times the fluctuations of the concentration field are stationary and the corresponding probability density functional can be evaluated analytically. In this limit the fluctuations depend on the distribution of the total number of particles but are independent of the initial positions of the particles. We show that the logarithm of the stationary probability functional plays the role of a nonequilibrium thermodynamic potential, which has a structure similar to the Helmholtz free energy in equilibrium thermodynamics: it is made up of the sum of an energetic component, depending on the external mechanical potential, and of an entropic component, depending on
International Nuclear Information System (INIS)
Kundin, Julia; Pogorelov, Evgeny; Emmerich, Heike
2015-01-01
We have investigated the microstructure evolution during the isothermal and non-isothermal solidification of ternary Al–Cu–Ni alloys by means of a general multi-phase-field model for an arbitrary number of phases. The stability requirements for the model functions on every dual interface guarantee the absence of “ghost” phases. The aim was to generate a realistic microstructure by coupling the thermodynamic parameters of the phases and the thermodynamically consistent phase-field evolution equations. It is shown that the specially constructed thermal noise terms disturb the stability on the dual interfaces and can produce heterogeneous nucleation of product phases at energetically favorable points. Similar behavior can be observed in triple junctions where the heterogeneous nucleation of a fourth phase is more favorable. Finally, the model predicts the growth of a combined eutectic-like and peritectic-like structure that is comparable to the observed experimental microstructure in various alloys
Energetically demanding transport in a supramolecular assembly.
Cheng, Chuyang; McGonigal, Paul R; Liu, Wei-Guang; Li, Hao; Vermeulen, Nicolaas A; Ke, Chenfeng; Frasconi, Marco; Stern, Charlotte L; Goddard, William A; Stoddart, J Fraser
2014-10-22
A challenge in contemporary chemistry is the realization of artificial molecular machines that can perform work in solution on their environments. Here, we report on the design and production of a supramolecular flashing energy ratchet capable of processing chemical fuel generated by redox changes to drive a ring in one direction relative to a dumbbell toward an energetically uphill state. The kinetics of the reaction pathway juxtapose a low energy [2]pseudorotaxane that forms under equilibrium conditions with a high energy, metastable [2]pseudorotaxane which resides away from equilibrium.
R&D of Energetic Ionic Liquids
2011-11-01
92oC) is also an Energetic Ionic Liquid • ADN-based monopropellant (LMP-103S) from ECAPS , Swedish Space Corporation • High performance „green...6 Toxicity Assessment of AF-M315E Toxicity Testing Results PROPERTY AF-M315E HYDRAZINE LD50 (rat), mg /kg 550 60 Dermal Irritation (rabbit...to yield low vapor toxicity – Sweden/ ECAPS LMP-103S • Propellant uses ADN-based formulation New PEP materials are likely to employ advanced
Reversibly formed bilayer vesicles: Energetics and polydispersity
DEFF Research Database (Denmark)
Bergstöm, M.
1997-01-01
orders of magnitude larger than where the local free energy minima of the equilibrium vesicle actually occur. Moreover, according to our analysis, the relative width of a vesicle size distribution, sigma(R)/R-max, is generally at full equilibrium equal to 0.283, independently of the energetic vesicle....... and a statistical-mechanical factor that accounts for the fluctuations in composition, chain packing density and shape. We demonstrate that the free energy required to form a spherical vesicle is made up of two main contributions: the (size-independent) work of bending the constituent monolayers and the work...
The energetic potential of bioethanol in Hungary
Directory of Open Access Journals (Sweden)
Károly Lakatos
2008-11-01
Full Text Available The basis of the bioethanol production is the agriculture, mostly the corn and wheat growing. With the analysis of their domesticharvest results, the process of the starch formation and the chemical-thermodynamical processes of the alcohol’s fermantation,we calculate the annual amount of the producible bioethanol on average and it’s energy. We determine the specific values of the CO2cycle. We examine the energetic possibilities of total substitution of the 2 billion litres of domestic petrol consumption with bioethanol.
Coucheron, David A.; Fokine, Michael; Patil, Nilesh; Breiby, Dag Werner; Buset, Ole Tore; Healy, Noel; Peacock, Anna C.; Hawkins, Thomas; Jones, Max; Ballato, John; Gibson, Ursula J.
2016-01-01
Glass fibres with silicon cores have emerged as a versatile platform for all-optical processing, sensing and microscale optoelectronic devices. Using SiGe in the core extends the accessible wavelength range and potential optical functionality because the bandgap and optical properties can be tuned by changing the composition. However, silicon and germanium segregate unevenly during non-equilibrium solidification, presenting new fabrication challenges, and requiring detailed studies of the alloy crystallization dynamics in the fibre geometry. We report the fabrication of SiGe-core optical fibres, and the use of CO2 laser irradiation to heat the glass cladding and recrystallize the core, improving optical transmission. We observe the ramifications of the classic models of solidification at the microscale, and demonstrate suppression of constitutional undercooling at high solidification velocities. Tailoring the recrystallization conditions allows formation of long single crystals with uniform composition, as well as fabrication of compositional microstructures, such as gratings, within the fibre core. PMID:27775066
Standing magnetic wave on Ising ferromagnet: Nonequilibrium phase transition
Energy Technology Data Exchange (ETDEWEB)
Halder, Ajay, E-mail: ajay.rs@presiuniv.ac.in; Acharyya, Muktish, E-mail: muktish.physics@presiuniv.ac.in
2016-12-15
The dynamical response of an Ising ferromagnet to a plane polarised standing magnetic field wave is modelled and studied here by Monte Carlo simulation in two dimensions. The amplitude of standing magnetic wave is modulated along the direction x. We have detected two main dynamical phases namely, pinned and oscillating spin clusters. Depending on the value of field amplitude the system is found to undergo a phase transition from oscillating spin cluster to pinned as the system is cooled down. The time averaged magnetisation over a full cycle of magnetic field oscillations is defined as the dynamic order parameter. The transition is detected by studying the temperature dependences of the variance of the dynamic order parameter, the derivative of the dynamic order parameter and the dynamic specific heat. The dependence of the transition temperature on the magnetic field amplitude and on the wavelength of the magnetic field wave is studied at a single frequency. A comprehensive phase boundary is drawn in the plane described by the temperature and field amplitude for two different wavelengths of the magnetic wave. The variation of instantaneous line magnetisation during a period of magnetic field oscillation for standing wave mode is compared to those for the propagating wave mode. Also the probability that a spin at any site, flips, is calculated. The above mentioned variations and the probability of spin flip clearly distinguish between the dynamical phases formed by propagating magnetic wave and by standing magnetic wave in an Ising ferromagnet. - Highlights: • The Ising ferromagnet. • The system is driven by standing magnetic wave. • The low temperature pinned phase is observed • The high temperature oscillating spin bands are observed • The nonequilibrium phase boundary is drawn.
Energetic Ion Loss Diagnostic for the Wendelstein 7-AS Stellarator
International Nuclear Information System (INIS)
Darrow, D. S.; Werner, A.; Weller, A.
2000-01-01
A diagnostic to measure the loss of energetic ions from the Wendelstein 7-AS (W7-AS) stellarator has been built. It is capable of measuring losses of both neutral beam ions and energetic ions arising from ion cyclotron resonant heating. The probe can measure losses of both clockwise and counterclockwise-going energetic ions simultaneously, and accepts a wide range of pitch angles in both directions. Initial measurements by the diagnostic are reported
Surface microstructure replication in injection molding
DEFF Research Database (Denmark)
Theilade, Uffe Arlø; Hansen, Hans Nørgaard
2006-01-01
molding of surface microstructures. The fundamental problem of surface microstructure replication has been studied. The research is based on specific microstructures as found in lab-on-a-chip products and on rough surfaces generated from EDM (electro discharge machining) mold cavities. Emphasis is put...
Advancing metal-oxide-semiconductor theory: Steady-state nonequilibrium conditions
Passlack, M.; Hong, M.; Schubert, E. F.; Zydzik, G. J.; Mannaerts, J. P.; Hobson, W. S.; Harris, T. D.
1997-06-01
This article investigates steady-state nonequilibrium conditions in metal-oxide-semiconductor (MOS) capacitors. Steady-state nonequilibrium conditions are of significant interest due to the advent of wide-gap semiconductors in the arena of MOS (or metal-insulator-semiconductor) devices and due to the scaling of oxide thickness in Si technology. Two major classes of steady-state nonequilibrium conditions were studied both experimentally and theoretically: (i) steady-state deep depletion and (ii) steady-state low level optical generation. It is found that the identification and subsequent understanding of steady-state nonequilibrium conditions is of significant importance for correct interpretation of electrical measurements such as capacitance-voltage and conductance-voltage measurements. Basic implications of steady-state nonequilibrium conditions were derived for both MOS capacitors with low interfaces state density Dit and for oxide semiconductor interfaces with a pinned Fermi level. Further, a photoluminescence power spectroscopy technique is investigated as a complementary tool for direct-gap semiconductors to study Dit and to monitor the interface quality during device fabrication.
NON-EQUILIBRIUM HELIUM IONIZATION IN AN MHD SIMULATION OF THE SOLAR ATMOSPHERE
International Nuclear Information System (INIS)
Golding, Thomas Peter; Carlsson, Mats; Leenaarts, Jorrit
2016-01-01
The ionization state of the gas in the dynamic solar chromosphere can depart strongly from the instantaneous statistical equilibrium commonly assumed in numerical modeling. We improve on earlier simulations of the solar atmosphere that only included non-equilibrium hydrogen ionization by performing a 2D radiation-magnetohydrodynamics simulation featuring non-equilibrium ionization of both hydrogen and helium. The simulation includes the effect of hydrogen Lyα and the EUV radiation from the corona on the ionization and heating of the atmosphere. Details on code implementation are given. We obtain helium ion fractions that are far from their equilibrium values. Comparison with models with local thermodynamic equilibrium (LTE) ionization shows that non-equilibrium helium ionization leads to higher temperatures in wavefronts and lower temperatures in the gas between shocks. Assuming LTE ionization results in a thermostat-like behavior with matter accumulating around the temperatures where the LTE ionization fractions change rapidly. Comparison of DEM curves computed from our models shows that non-equilibrium ionization leads to more radiating material in the temperature range 11–18 kK, compared to models with LTE helium ionization. We conclude that non-equilibrium helium ionization is important for the dynamics and thermal structure of the upper chromosphere and transition region. It might also help resolve the problem that intensities of chromospheric lines computed from current models are smaller than those observed
Dütsch, Marina; Pfahl, Stephan; Sodemann, Harald
2017-12-01
The deuterium excess (d) is a useful measure for nonequilibrium effects of isotopic fractionation and can therefore provide information about the meteorological conditions in evaporation regions or during ice cloud formation. In addition to nonequilibrium fractionation, two other effects can change d during phase transitions. The first is the dependence of the equilibrium fractionation factors on temperature, and the second is the nonlinearity of the δ scale on which d is defined. The second effect can be avoided by using an alternative definition that is based on the logarithmic scale. However, in this case d is not conserved when air parcels mix, which can lead to changes without phase transitions. Here we provide a systematic analysis of the benefits and limitations of both deuterium excess definitions by separately quantifying the impact of the nonequilibrium effect, the temperature effect, the δ-scale effect, and the mixing effect in a simple Rayleigh model simulating the isotopic composition of air parcels during moist adiabatic ascent. The δ-scale effect is important in depleted air parcels, for which it can change the sign of the traditional deuterium excess in the remaining vapor from negative to positive. The alternative definition mainly reflects the nonequilibrium and temperature effect, while the mixing effect is about 2 orders of magnitude smaller. Thus, the alternative deuterium excess definition appears to be a more accurate measure for nonequilibrium effects in situations where moisture is depleted and the δ-scale effect is large, for instance, at high latitudes or altitudes.
Sobolev, S. L.
2018-02-01
Some analogies between different nonequilibrium heat conduction models, particularly random walk, the discrete variable model, and the Boltzmann transport equation with the single relaxation time approximation, have been discussed. We show that, under an assumption of a finite value of the heat carrier velocity, these models lead to the hyperbolic heat conduction equation and the modified Fourier law with relaxation term. Corresponding effective temperature and entropy have been introduced and analyzed. It has been demonstrated that the effective temperature, defined as a geometric mean of the kinetic temperatures of the heat carriers moving in opposite directions, acts as a criterion for thermalization and is a nonlinear function of the kinetic temperature and heat flux. It is shown that, under highly nonequilibrium conditions when the heat flux tends to its maximum possible value, the effective temperature, heat capacity, and local entropy go to zero even at a nonzero equilibrium temperature. This provides a possible generalization of the third law to nonequilibrium situations. Analogies and differences between the proposed effective temperature and some other definitions of a temperature in nonequilibrium state, particularly for active systems, disordered semiconductors under electric field, and adiabatic gas flow, have been shown and discussed. Illustrative examples of the behavior of the effective temperature and entropy during nonequilibrium heat conduction in a monatomic gas and a strong shockwave have been analyzed.
International Nuclear Information System (INIS)
Roh, Heui-Seol
2015-01-01
Chemical energy transfer mechanisms at finite temperature are explored by a chemical energy transfer theory which is capable of investigating various chemical mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium. Gibbs energy fluxes are obtained as a function of chemical potential, time, and displacement. Diffusion, convection, internal convection, and internal equilibrium chemical energy fluxes are demonstrated. The theory reveals that there are chemical energy flux gaps and broken discrete symmetries at the activation chemical potential, time, and displacement. The statistical, thermodynamic theory is the unification of diffusion and internal convection chemical reactions which reduces to the non-equilibrium generalization beyond the quasi-equilibrium theories of migration and diffusion processes. The relationship between kinetic theories of chemical and electrochemical reactions is also explored. The theory is applied to explore non-equilibrium chemical reactions as an illustration. Three variable separation constants indicate particle number constants and play key roles in describing the distinct chemical reaction mechanisms. The kinetics of chemical energy transfer accounts for the four control mechanisms of chemical reactions such as activation, concentration, transition, and film chemical reactions. - Highlights: • Chemical energy transfer theory is proposed for non-, quasi-, and equilibrium. • Gibbs energy fluxes are expressed by chemical potential, time, and displacement. • Relationship between chemical and electrochemical reactions is discussed. • Theory is applied to explore nonequilibrium energy transfer in chemical reactions. • Kinetics of non-equilibrium chemical reactions shows the four control mechanisms
Effects of Nonequilibrium at Edge of Boundary Layer on Convective Heat Transfer to a Blunt Body
Goekcen, Tahir; Edwards, Thomas A. (Technical Monitor)
1996-01-01
This investigation is a continuation of a previous study on nonequilibrium convective heat transfer to a blunt body. In the previous study, for relatively high Reynolds number flows, it was found that: nonequilibrium convective heat transfer to a blunt body is not strongly dependent on freestream parameters, provided that the thermochemical equilibrium is reached at the edge of boundary layer; and successful testing of convective heat transfer in an arc-jet environment is possible by duplicating the surface pressure and total enthalpy. The nonequilibrium convective heat transfer computations are validated against the results of Fay and Riddell/Goulard theory. Present work investigates low Reynolds number conditions which are typical in an actual arc-jet flow environment. One expects that there will be departures from the Fay and Riddell/Goulard result since certain assumptions of the classical theory are not satisfied. These departures are of interest because the Fay and Riddell/Goulard formulas are extensively used in arc-jet testing (e.g., to determine the enthalpy of the flow and the catalytic efficiency of heat shield materials). For practical sizes of test materials, density of the test flow (and Reynolds number) in an arc-jet is such that thermochemical equilibrium may not be reached at the edge of boundary layer. For blunt body flows of nitrogen and air, computations will be presented to show the effects of thermochemical nonequilibrium at the boundary layer edge on nonequilibrium heat transfer.
Segregation and redistribution of end-of-process energetic materials
International Nuclear Information System (INIS)
McCabe, R.A.; Cummins, B.; Gonzalez, M.A.
1993-03-01
A system recovering then recycling or reusing end-of-process energetic materials has been developed at the Lawrence Livermore National Laboratory (LLNL). The system promotes separating energetic materials with high potential for reuse or recycling from those that have no further value. A feature of the system is a computerized electronic bulletin board for advertising the availability of surplus and recovered energetic materials and process chemicals to LLNL researchers, and for posting energetic materials, ''want ads.'' The system was developed and implemented to promote waste minimization and pollution prevention at LLNL
Ultrafast Vibrational Spectrometer for Engineered Nanometric Energetic Materials
National Research Council Canada - National Science Library
Dlott, Dana
2002-01-01
The proposer requested funding for laser equipment that would be used to study engineered nanometric energetic materials consisting of nanometer metal particles, passivation layers and oxidizing binders...
Chemical Dynamics Studies of Reactions in Energetic Materials
National Research Council Canada - National Science Library
Thompson, Donald O
1997-01-01
A theoretical/computational research program to develop methods, simulate complex reactions, and investigate the fundamental chemical dynamics of reactions of nitramine energetic materials occurring...
Preliminary Hazard Analysis of Supercritical Fluid Separation of Energetic Materials
National Research Council Canada - National Science Library
1997-01-01
.... Army Research Laboratory (ARL) and elsewhere, particularly at the Phasex Corporation, Lawrence, MA, has demonstrated the feasibility of separating the energetic moieties by use of supercritical CO2...
The roles of energetic displacement cascades in ion beam modifications of materials
International Nuclear Information System (INIS)
Averback, R.S.; Kim, S.J.; De la Rubia, T.D.
1987-01-01
The roles of energetic displacement cascades are ubiquitous in the fields of radiation damage and ion beam modifications of materials. These roles can be described on two time scales. For the first, which lasts ≅ 10/sup -11/ s, small cascade volumes are characterized by large supersaturations of point defects, structural disorder, and energy densities in excess of some tenths of eV's per atom. During this period, the system can be driven far from equilibrium with significant rearrangement of target atoms and the production of Frenkel pairs. Experimental studies of ion beam mixing in conjunction with molecular dynamics computer simulations, have contributed largely toward understanding these dynamic cascade processes. At later times, the microstructure of the material evolves as cascades begin to overlap, or at elevated temperatures, point defects migrate away from their nascent cascades. It is shown how the primary state of damage in cascades influences this microstructural development. Examples involving radiation-enhanced diffusion and ion-induced amorphization are discussed
Radicals and Non-Equilibrium Processes in Low-Temperature Plasmas
Petrović, Zoran; Mason, Nigel; Hamaguchi, Satoshi; Radmilović-Radjenović, Marija
2007-06-01
Serbian Academy of Sciences and Arts and Institute of Physics, Belgrade. Each Symposium has sought to highlight a key topic of plasma research and the 5th EU - Japan symposium explored the role of Radicals and Non-Equilibrium Processes in Low-Temperature Plasmas since these are key elements of plasma processing. Other aspects of technologies for manufacturing integrated circuits were also considered. Unlike bio-medicine and perhaps politics, in plasma processing free radicals are `good radicals' but their kinetics are difficult to understand since there remains little data on their collisions with electrons and ions. One of the goals of the symposium was to facilitate communication between experimentalists and theorists in binary collision physics with plasma modellers and practitioners of plasma processing in order to optimize efforts to provide much needed data for both molecules and radicals of practical importance. The non-equilibrium nature of plasmas is critical in the efficient manufacturing of high resolution structures by anisotropic plasma etching on Si wafers since they allow separate control of the directionality and energy of ions and provide a high level of separation between the mean energies of electrons and ions. As nanotechnologies become practical, plasma processing may play a key role, not only in manufacturing of integrated circuits, but also for self-organization of massively parallel manufacturing of nanostructures. In this Symposium the key issues that are hindering the development of such new, higher resolution technologies were discussed and some possible solutions were proposed. In particular, damage control, fast neutral etching, processes at surface and modeling of profiles were addressed in several of the lectures. A wide range of topics are covered in this book including atomic and molecular collision physics - primarily focused towards formation and analysis of radicals, basic swarm data and breakdown kinetics, basic kinetics of RF and DC
Modelling of energetic molecule-surface interactions
International Nuclear Information System (INIS)
Kerford, M.
2000-09-01
This thesis contains the results of molecular dynamics simulations of molecule-surface interactions, looking particularly at fullerene molecules and carbon surfaces. Energetic impacts of fullerene molecules on graphite create defect craters. The relationship between the parameters of the impacting molecule and the parameters of the crater axe examined and found to be a function of the energy and velocity of the impacting molecule. Less energetic fullerene molecules can be scattered from a graphite surface and the partitioning of energy after a scattering event is investigated. It is found that a large fraction of the kinetic energy retained after impact is translational energy, with a small fraction of rotational energy and a number of vibrational modes. At impact energies where the surface is not broken and at normal incidence, surface waves axe seen to occur. These waves axe used to develop a method of desorbing molecules from a graphite surface without damage to either the surface or the molecules being desorbed. A number of fullerene molecules are investigated and ways to increase the desorption yield are examined. It is found that this is a successful technique for desorbing large numbers of intact molecules from graphite. This technique could be used for desorbing intact molecules into a gas phase for mass spectrometric analysis. (author)
Energetic particle mode dynamics in tokamaks
International Nuclear Information System (INIS)
Zonca, F.; Briguglio, S.; Fogaccia, G.; Vlad, G.; Chen, L.; Zheng, L.-J.
2001-01-01
Energetic Particle Modes (EPM) are strongly driven oscillations excited via wave-particle resonant interactions at the characteristic frequencies of the energetic ions, ω tE , ω BE and/or ω-bar dE , i.e., respectively the transit frequency for circulating particles and the bounce and precessional drift frequencies for trapped ions. A sharp transition in the plasma stability at the critical EPM excitation threshold has been observed by nonperturbative gyrokinetic codes in terms of changes in normalized growth rate (γ/ω A , with ω A =ν A /qR 0 ), real frequency (ω r /ω A ) and parallel wave vector (k parallel qR 0 ) both as α=-R 0 q 2 β' of the thermal plasma and that, α E of fast ions are varied. The present work further explores theoretical aspects of EPM excitations by spatially localized particle sources, possibly associated with frequency chirping, which can radially trap the EPM in the region where the free energy source is strongest. Results of a nonperturbative 3D Hybrid MHD Gyrokinetic code are also presented to emphasize that nonlinear behaviors of EPM's are different from those of Toroidal Alfven Eigenmodes (TAE) and Kinetic TAE (KTAE) and that particle losses and mode saturation are consistent with the mode-particle pumping model (particle radial convection). Results of theoretical analyses of nonlinear EPM dynamics are also presented and the possible overlap with more general nonlinear dynamics problems is discussed. (author)
Energetic Constraints on Species Coexistence in Birds.
Pigot, Alexander L; Tobias, Joseph A; Jetz, Walter
2016-03-01
The association between species richness and ecosystem energy availability is one of the major geographic trends in biodiversity. It is often explained in terms of energetic constraints, such that coexistence among competing species is limited in low productivity environments. However, it has proven challenging to reject alternative views, including the null hypothesis that species richness has simply had more time to accumulate in productive regions, and thus the role of energetic constraints in limiting coexistence remains largely unknown. We use the phylogenetic relationships and geographic ranges of sister species (pairs of lineages who are each other's closest extant relatives) to examine the association between energy availability and coexistence across an entire vertebrate class (Aves). We show that the incidence of coexistence among sister species increases with overall species richness and is elevated in more productive ecosystems, even when accounting for differences in the evolutionary time available for coexistence to occur. Our results indicate that energy availability promotes species coexistence in closely related lineages, providing a key step toward a more mechanistic understanding of the productivity-richness relationship underlying global gradients in biodiversity.
Photomask repair using low-energetic electrons
Edinger, K.; Wolff, K.; Spies, P.; Luchs, T.; Schneider, H.; Auth, N.; Hermanns, Ch. F.; Waiblinger, M.
2015-10-01
Mask repair is an essential step in the mask manufacturing process as the extension of 193nm technology and the insertion of EUV are drivers for mask complexity and cost. The ability to repair all types of defects on all mask blank materials is crucial for the economic success of a mask shop operation. In the future mask repair is facing several challenges. The mask minimum features sizes are shrinking and require a higher resolution repair tool. At the same time mask blanks with different new mask materials are introduced to optimize optical performance and long term durability. For EUV masks new classes of defects like multilayer and phase defects are entering the stage. In order to achieve a high yield, mask repair has to cover etch and deposition capabilities and must not damage the mask. We will demonstrate in this paper that low energetic electron-beam (e-beam)-based mask repair is a commercially viable solution. Therefore we developed a new repair platform called MeRiT® neXT to address the technical challenges of this new technology. We will analyze the limits of the existing as well as lower energetic electron induced repair technologies theoretically and experimentally and show performance data on photomask reticles. Based on this data, we will give an outlook to future mask repair technology.
Nonlinear microstructured polymer optical fibres
DEFF Research Database (Denmark)
Frosz, Michael Henoch
is potentially the case for microstructured polymer optical fibres (mPOFs). Another advantage is that polymer materials have a higher biocompatibility than silica, meaning that it is easier to bond certain types of biosensor materials to a polymer surface than to silica. As with silica PCFs, it is difficult...
Microstructural processes in irradiated materials
Byun, Thak Sang; Morgan, Dane; Jiao, Zhijie; Almer, Jonathan; Brown, Donald
2016-04-01
These proceedings contain the papers presented at two symposia, the Microstructural Processes in Irradiated Materials (MPIM) and Characterization of Nuclear Reactor Materials and Components with Neutron and Synchrotron Radiation, held in the TMS 2015, 144th Annual Meeting & Exhibition at Walt Disney World, Orlando, Florida, USA on March 15-19, 2015.
Strength and Microstructure of Ceramics
1990-11-01
Oxide as a Function of Temperature and Grain initial flaw in this domain (attributable to the T-curve stabi- Size," J. Am. Cerom . Soc.. 4 (7] 323-27...increasingly Propagate Inherent Flaws," Proc. Br. Cerom . Sac., 20, 275-97 (1972). larger than their microstructural counterparts and thereby 1R. E
Microstructured Reactors for Electroorganic Synthesis
Czech Academy of Sciences Publication Activity Database
Bouzek, K.; Jiřičný, Vladimír; Kodým, R.; Křišťál, Jiří; Bystroň, T.
2010-01-01
Roč. 55, č. 7 (2010), s. 8172-8181 ISSN 0013-4686. [Annual Meeting of ISE /60./. Beijing, 16.08.2009-21.08.2009] Institutional research plan: CEZ:AV0Z40720504 Keywords : microstructured reactor * bipolar * electroorganic synthesis Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.642, year: 2010
A 3-D microstructural level model for analyzing the response of polymer bonded explosives
Hardin, David; Zhou, Min
2011-06-01
A three-dimensional finite element model is developed to study the microstructural level response of polymer-bonded explosives (PBX) under impact loading. The study focuses on the effect of the morphology and packing of energetic grains on the overall thermomechanical response of the composites. A cohesive finite element method (CFEM) is utilized to account for failure in the form of debonding between the HMX grains and the polymer matrix. Frictional heating along crack faces is tracked through a contact algorithm. Microstructures with cubic and multifaceted three-dimensional polygonal granules with packing densities between 0.42 and 0.74 are generated and used. Both 2D and 3D calculations are carried to analyze the differences between the models. To ensure consistency, the 2D microstructures are sections of the 3D microstructures. In this presentation, we will discuss differences in results from the 2D and 3D calculations, with a particular focus on the progression of damage and heating under impact loading.
Microstructured metal molds fabricated via investment casting
International Nuclear Information System (INIS)
Cannon, Andrew H; King, William P
2010-01-01
This paper describes an investment casting process to produce aluminum molds having integrated microstructures. Unlike conventional micromolding tools, the aluminum mold was large and had complex curved surfaces. The aluminum was cast from curved microstructured ceramic molds which were themselves cast from curved microstructured rubber. The aluminum microstructures had an aspect ratio of 1:1 and sizes ranging from 25 to 50 µm. Many structures were successfully cast into the aluminum with excellent replication fidelity, including circular, square and triangular holes. We demonstrate molding of large, curved surfaces having surface microstructures using the aluminum mold.
Nonequilibrium Green function theory for excitation and transport in atoms and molecules
International Nuclear Information System (INIS)
Dahlen, Nils Erik; Stan, Adrian; Leeuwen, Robert van
2006-01-01
In this work we discuss the application of nonequilibrium Green functions theory to atomic and molecular systems with the aim to study charge and energy transport in these systems. We apply the Kadanoff-Baym equations to atoms and diatomic molecules initially in the ground state. The results obtained for the correlated initial states are used to analyze variational energy functionals of the Green function which are shown to perform very well. We further show an application of the Kadanoff-Baym equations to a molecule exposed to an external laser field. Finally we discuss the connection between nonequilibrium Green function theory and time-dependent density-functional theory with the aim to develop better density functionals in order to treat larger systems than those attainable with the nonequilibrium Green function method
Surface-ionization field mass-spectrometry studies of nonequilibrium surface ionization
International Nuclear Information System (INIS)
Blashenkov, Nikolai M; Lavrent'ev, Gennadii Ya
2007-01-01
The ionization of polyatomic molecules on tungsten and tungsten oxide surfaces is considered for quasiequilibrium or essentially nonequilibrium conditions (in the latter case, the term nonequilibrium surface ionization is used for adsorbate ionization). Heterogeneous reactions are supposed to proceed through monomolecular decay of polyatomic molecules or fragments of multimolecular complexes. The nonequilibrium nature of these reactions is established. The dependences of the current density of disordered ions on the surface temperature, electric field strength, and ionized particle energy distribution are obtained in analytical form. Heterogeneous dissociation energies, the ionization potentials of radicals, and the magnitude of reaction departure from equilibrium are determined from experimental data, as are energy exchange times between reaction products and surfaces, the number of molecules in molecular complexes, and the number of effective degrees of freedom in molecules and complexes. In collecting the data a new technique relying on surface-ionization field mass-spectrometry was applied. (instruments and methods of investigation)
Replacing leads by self-energies using non-equilibrium Green's functions
International Nuclear Information System (INIS)
Michael, Fredrick; Johnson, M.D.
2003-01-01
Open quantum systems consist of semi-infinite leads which transport electrons to and from the device of interest. We show here that within the non-equilibrium Green's function technique for continuum systems, the leads can be replaced by simple c-number self-energies. Our starting point is an approach for continuum systems developed by Feuchtwang. The reformulation developed here is simpler to understand and carry out than the somewhat unwieldly manipulations typical in the Feuchtwang method. The self-energies turn out to have a limited variability: the retarded self-energy Σ r depends on the arbitrary choice of internal boundary conditions, but the non-equilibrium self-energy or scattering function Σ which determines transport is invariant for a broad class of boundary conditions. Expressed in terms of these self-energies, continuum non-equilibrium transport calculations take a particularly simple form similar to that developed for discrete systems
Non-equilibrium scaling analysis of the Kondo model with voltage bias
International Nuclear Information System (INIS)
Fritsch, Peter; Kehrein, Stefan
2009-01-01
The quintessential description of Kondo physics in equilibrium is obtained within a scaling picture that shows the buildup of Kondo screening at low temperature. For the non-equilibrium Kondo model with a voltage bias, the key new feature are decoherence effects due to the current across the impurity. In the present paper, we show how one can develop a consistent framework for studying the non-equilibrium Kondo model within a scaling picture of infinitesimal unitary transformations (flow equations). Decoherence effects appear naturally in third order of the β-function and dominate the Hamiltonian flow for sufficiently large voltage bias. We work out the spin dynamics in non-equilibrium and compare it with finite temperature equilibrium results. In particular, we report on the behavior of the static spin susceptibility including leading logarithmic corrections and compare it with the celebrated equilibrium result as a function of temperature.
Beyond the second law entropy production and non-equilibrium systems
Lineweaver, Charles; Niven, Robert; Regenauer-Lieb, Klaus
2014-01-01
The Second Law, a cornerstone of thermodynamics, governs the average direction of dissipative, non-equilibrium processes. But it says nothing about their actual rates or the probability of fluctuations about the average. This interdisciplinary book, written and peer-reviewed by international experts, presents recent advances in the search for new non-equilibrium principles beyond the Second Law, and their applications to a wide range of systems across physics, chemistry and biology. Beyond The Second Law brings together traditionally isolated areas of non-equilibrium research and highlights potentially fruitful connections between them, with entropy production playing the unifying role. Key theoretical concepts include the Maximum Entropy Production principle, the Fluctuation Theorem, and the Maximum Entropy method of statistical inference. Applications of these principles are illustrated in such diverse fields as climatology, cosmology, crystal growth morphology, Earth system science, environmental physics, ...
The impact of episodic nonequilibrium fracture-matrix flow on geological repository performance
International Nuclear Information System (INIS)
Buscheck, T.A.; Nitao, J.J.; Chestnut, D.A.
1991-01-01
Adequate representation of fracture-matrix interaction during episodic infiltration events is crucial in making valid hydrological predictions of repository performance at Yucca Mountain. Various approximations have been applied to represent fracture-matrix flow interaction, including the Equivalent Continuum Model (ECM), which assumes capillary equilibrium between fractures and matrix, and the Fracture-Matrix Model (FMM), which accounts for nonequilibrium fracture-matrix flow. We analyze the relative impact of matrix imbibition on episodic nonequilibrium fracture-matrix flow for the eight major hydrostratigraphic units in the unsaturated zone at Yucca Mountain. Comparisons are made between ECM and FMM predictions to determine the applicability of the ECM. The implications of nonequilibrium fracture-matrix flow on radionuclide transport are also discussed
Phase transitions, nonequilibrium dynamics, and critical behavior of strongly interacting systems
Energy Technology Data Exchange (ETDEWEB)
Mottola, E.; Bhattacharya, T.; Cooper, F. [and others
1998-12-31
This is the final report of a three-year, Laboratory Directed Research and Development project at Los Alamos National Laboratory. In this effort, large-scale simulations of strongly interacting systems were performed and a variety of approaches to the nonequilibrium dynamics of phase transitions and critical behavior were investigated. Focus areas included (1) the finite-temperature quantum chromodynamics phase transition and nonequilibrium dynamics of a new phase of matter (the quark-gluon plasma) above the critical temperature, (2) nonequilibrium dynamics of a quantum fields using mean field theory, and (3) stochastic classical field theoretic models with applications to spinodal decomposition and structural phase transitions in a variety of systems, such as spin chains and shape memory alloys.
Nonequilibrium behaviors of the three-dimensional Heisenberg model in the Swendsen-Wang algorithm
Nonomura, Yoshihiko; Tomita, Yusuke
2016-01-01
Recently, it was shown [Y. Nonomura, J. Phys. Soc. Jpn. 83, 113001 (2014), 10.7566/JPSJ.83.113001] that the nonequilibrium critical relaxation of the two-dimensional (2D) Ising model from a perfectly ordered state in the Wolff algorithm is described by stretched-exponential decay, and a universal scaling scheme was found to connect nonequilibrium and equilibrium behaviors. In the present study we extend these findings to vector spin models, and the 3D Heisenberg model could be a typical example. To evaluate the critical temperature and critical exponents precisely using the above scaling scheme, we calculate nonequilibrium ordering from the perfectly disordered state in the Swendsen-Wang algorithm, and we find that the critical ordering process is described by stretched-exponential growth with a comparable exponent to that of the 3D X Y model. The critical exponents evaluated in the present study are consistent with those in previous studies.
Yu, Minghao; Takahashi, Yusuke; Kihara, Hisashi; Abe, Ken-ichi; Yamada, Kazuhiko; Abe, Takashi
2014-12-01
Numerical investigation of nonequilibrium inductively coupled plasma (ICP) flow was carried out to study the physical properties of the flow inside a 10-kW ICP torch with the working gas being nitrogen. The flow field was described by two-dimensional compressible axisymmetric Navier-Stokes (N-S) equations that took into account 5 species and 8 chemical reactions. The magnetic vector-potential equations were tightly coupled with the flow-field equations to describe the heating process by inductive discharge. A four-temperature model was adopted to model thermal nonequilibrium process in the discharge torch. The characteristics of ICP flow such as thermal nonequilibrium, inductive discharge, and strong effects of Lorentz forces became clear through the present study.
Non-equilibrium assembly of microtubules: from molecules to autonomous chemical robots.
Hess, H; Ross, Jennifer L
2017-09-18
Biological systems have evolved to harness non-equilibrium processes from the molecular to the macro scale. It is currently a grand challenge of chemistry, materials science, and engineering to understand and mimic biological systems that have the ability to autonomously sense stimuli, process these inputs, and respond by performing mechanical work. New chemical systems are responding to the challenge and form the basis for future responsive, adaptive, and active materials. In this article, we describe a particular biochemical-biomechanical network based on the microtubule cytoskeletal filament - itself a non-equilibrium chemical system. We trace the non-equilibrium aspects of the system from molecules to networks and describe how the cell uses this system to perform active work in essential processes. Finally, we discuss how microtubule-based engineered systems can serve as testbeds for autonomous chemical robots composed of biological and synthetic components.
Nonequilibrium Distribution of the Microscopic Thermal Current in Steady Thermal Transport Systems
Yukawa, Satoshi
2010-01-01
Nonequilibrium distribution of the microscopic thermal current is investigated by direct molecular dynamics simulations. The microscopic thermal current in this study is defined by a flow of kinetic energy carried by a single particle. Asymptotic parallel and antiparallel tails of the nonequilibrium distribution to an average thermal current are identical to ones of equilibrium distribution with different temperatures. These temperatures characterizing the tails are dependent on a characteristic length in which a memory of dynamics is completely erased by several particle collisions. This property of the tails of nonequilibrium distribution is confirmed in other thermal transport systems. In addition, statistical properties of a particle trapped by a harmonic potential in a steady thermal conducting state are also studied. This particle feels a finite force parallel to the average thermal current as a consequence of the skewness of the distribution of the current. This force is interpreted as the microscopic origin of thermophoresis.
Nonequilibrium dynamics of strings in time-dependent plane wave backgrounds
Energy Technology Data Exchange (ETDEWEB)
Nardi, R., E-mail: rnardi@cbpf.br [Centro Brasileiro de Pesquisas Fisicas (CBPF), R. Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro, RJ (Brazil); Vancea, I.V., E-mail: ionvancea@ufrrj.br [Grupo de Fisica Teorica e Matematica Fisica, Departamento de Fisica, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Cx. Postal 23851, BR 465 Km 7, 23890-000 Seropedica, RJ (Brazil)
2012-06-21
We formulate and study the nonequilibrium dynamics of strings near the singularity of the time-dependent plane wave background in the framework of the Nonequilibrium Thermo Field Dynamics (NETFD). In particular, we construct the Hilbert space of the thermal string oscillators at nonequilibrium and generalize the NETFD to describe the coordinates of the center of mass of the thermal string. The equations of motion of the thermal fields and the Hamiltonian are derived. Due to the time-dependence of the oscillator frequencies, a counterterm is present in the Hamiltonian. This counterterm determines the correlation functions in a perturbative fashion. We compute the two point correlation function of the thermal string at zero order in the power expansion.
Effect of non-equilibrium flow chemistry and surface catalysis on surface heating to AFE
Stewart, David A.; Henline, William D.; Chen, Yih-Kanq
1991-01-01
The effect of nonequilibrium flow chemistry on the surface temperature distribution over the forebody heat shield on the Aeroassisted Flight Experiment (AFE) vehicle was investigated using a reacting boundary-layer code. Computations were performed by using boundary-layer-edge properties determined from global iterations between the boundary-layer code and flow field solutions from a viscous shock layer (VSL) and a full Navier-Stokes solution. Surface temperature distribution over the AFE heat shield was calculated for two flight conditions during a nominal AFE trajectory. This study indicates that the surface temperature distribution is sensitive to the nonequilibrium chemistry in the shock layer. Heating distributions over the AFE forebody calculated using nonequilibrium edge properties were similar to values calculated using the VSL program.
Non-equilibrium versus equilibrium emission of complex fragments from hot nuclei
International Nuclear Information System (INIS)
Viola, V.E.; Kwiatkowski, K.; Yennello, S.; Fields, D.E.
1989-01-01
The relative contributions of equilibrium and non-equilibrium mechanisms for intermediate-mass fragment emission have been deduced for Z=3-14 fragments formed in 3 He- and 14 N-induced reactions on Ag and Au targets. Complete inclusive excitation function measurements have been performed for 3 He projectiles from E/A=67 to 1,200 MeV and for 14 N from E/A=20 to 50 MeV. The data are consistent with a picture in which equilibrated emission is important at the lowest energies, but with increasing bombarding energy the cross sections are increasingly dominated by non-equilibrium processes. Non-equilibrium emission is also shown to be favored for light fragments relative to heavy fragments. These results are supported by coincidence studies of intermediate-mass fragments tagged by linear momentum transfer measurements
X-RAY SIGNATURES OF NON-EQUILIBRIUM IONIZATION EFFECTS IN GALAXY CLUSTER ACCRETION SHOCK REGIONS
International Nuclear Information System (INIS)
Wong, Ka-Wah; Sarazin, Craig L.; Ji Li
2011-01-01
The densities in the outer regions of clusters of galaxies are very low, and the collisional timescales are very long. As a result, heavy elements will be under-ionized after they have passed through the accretion shock. We have studied systematically the effects of non-equilibrium ionization for relaxed clusters in the ΛCDM cosmology using one-dimensional hydrodynamic simulations. We found that non-equilibrium ionization effects do not depend on cluster mass, but depend strongly on redshift which can be understood by self-similar scaling arguments. The effects are stronger for clusters at lower redshifts. We present X-ray signatures such as surface brightness profiles and emission lines in detail for a massive cluster at low redshift. In general, soft emission (0.3-1.0 keV) is enhanced significantly by under-ionization, and the enhancement can be nearly an order of magnitude near the shock radius. The most prominent non-equilibrium ionization signature we found is the O VII and O VIII line ratio. The ratios for non-equilibrium ionization and collisional ionization equilibrium models are different by more than an order of magnitude at radii beyond half of the shock radius. These non-equilibrium ionization signatures are equally strong for models with different non-adiabatic shock electron heating efficiencies. We have also calculated the detectability of the O VII and O VIII lines with the future International X-ray Observatory (IXO). Depending on the line ratio measured, we conclude that an exposure of ∼130-380 ks on a moderate-redshift, massive regular cluster with the X-ray Microcalorimeter Spectrometer (XMS) on the IXO will be sufficient to provide a strong test for the non-equilibrium ionization model.
Reichhardt, C.; Olson Reichhardt, C. J.
2017-02-01
We review the depinning and nonequilibrium phases of collectively interacting particle systems driven over random or periodic substrates. This type of system is relevant to vortices in type-II superconductors, sliding charge density waves, electron crystals, colloids, stripe and pattern forming systems, and skyrmions, and could also have connections to jamming, glassy behaviors, and active matter. These systems are also ideal for exploring the broader issues of characterizing transient and steady state nonequilibrium flow phases as well as nonequilibrium phase transitions between distinct dynamical phases, analogous to phase transitions between different equilibrium states. We discuss the differences between elastic and plastic depinning on random substrates and the different types of nonequilibrium phases which are associated with specific features in the velocity-force curves, fluctuation spectra, scaling relations, and local or global particle ordering. We describe how these quantities can change depending on the dimension, anisotropy, disorder strength, and the presence of hysteresis. Within the moving phase we discuss how there can be a transition from a liquid-like state to dynamically ordered moving crystal, smectic, or nematic states. Systems with periodic or quasiperiodic substrates can have multiple nonequilibrium second or first order transitions in the moving state between chaotic and coherent phases, and can exhibit hysteresis. We also discuss systems with competing repulsive and attractive interactions, which undergo dynamical transitions into stripes and other complex morphologies when driven over random substrates. Throughout this work we highlight open issues and future directions such as absorbing phase transitions, nonequilibrium work relations, inertia, the role of non-dissipative dynamics such as Magnus effects, and how these results could be extended to the broader issues of plasticity in crystals, amorphous solids, and jamming phenomena.
Leij, Feike J; Bradford, Scott A
2009-11-20
The transport of solutes and colloids in porous media is influenced by a variety of physical and chemical nonequilibrium processes. A combined physical-chemical nonequilibrium (PCNE) model was therefore used to describe general mass transport. The model partitions the pore space into "mobile" and "immobile" flow regions with first-order mass transfer between these two regions (i.e, "physical" nonequilibrium or PNE). Partitioning between the aqueous and solid phases can either proceed as an equilibrium or a first-order process (i.e, "chemical" nonequilibrium or CNE) for both the mobile and immobile regions. An analytical solution for the PCNE model is obtained using iterated Laplace transforms. This solution complements earlier semi-analytical and numerical approaches to model solute transport with the PCNE model. The impact of selected model parameters on solute breakthrough curves is illustrated. As is well known, nonequilibrium results in earlier solute breakthrough with increased tailing. The PCNE model allows greater flexibility to describe this trend; for example, a closer resemblance between solute input and effluent pulse. Expressions for moments and transfer functions are presented to facilitate the analytical use of the PCNE model. Contours of mean breakthrough time, variance, and spread of the colloid breakthrough curves as a function of PNE and CNE parameters demonstrate the utility of a model that accounts for both physical and chemical nonequilibrium processes. The model is applied to describe representative colloid breakthrough curves in Ottawa sands reported by Bradford et al. (2002). An equilibrium model provided a good description of breakthrough curves for the bromide tracer but could not adequately describe the colloid data. A considerably better description was provide by the simple CNE model but the best description, especially for the larger 3.2-microm colloids, was provided by the PCNE model.
Behavior of Triple Langmuir Probes in Non-Equilibrium Plasmas
Polzin, Kurt A.; Ratcliffe, Alicia C.
2018-01-01
The triple Langmuir probe is an electrostatic probe in which three probe tips collect current when inserted into a plasma. The triple probe differs from a simple single Langmuir probe in the nature of the voltage applied to the probe tips. In the single probe, a swept voltage is applied to the probe tip to acquire a waveform showing the collected current as a function of applied voltage (I-V curve). In a triple probe three probe tips are electrically coupled to each other with constant voltages applied between each of the tips. The voltages are selected such that they would represent three points on the single Langmuir probe I-V curve. Elimination of the voltage sweep makes it possible to measure time-varying plasma properties in transient plasmas. Under the assumption of a Maxwellian plasma, one can determine the time-varying plasma temperature T(sub e)(t) and number density n(sub e)(t) from the applied voltage levels and the time-histories of the collected currents. In the present paper we examine the theory of triple probe operation, specifically focusing on the assumption of a Maxwellian plasma. Triple probe measurements have been widely employed for a number of pulsed and timevarying plasmas, including pulsed plasma thrusters (PPTs), dense plasma focus devices, plasma flows, and fusion experiments. While the equilibrium assumption may be justified for some applications, it is unlikely that it is fully justifiable for all pulsed and time-varying plasmas or for all times during the pulse of a plasma device. To examine a simple non-equilibrium plasma case, we return to basic governing equations of probe current collection and compute the current to the probes for a distribution function consisting of two Maxwellian distributions with different temperatures (the two-temperature Maxwellian). A variation of this method is also employed, where one of the Maxwellians is offset from zero (in velocity space) to add a suprathermal beam of electrons to the tail of the
Nonequilibrium phenomena in chiral physics and hot gauge theories
Sivaramakrishnan, Prem Kumar
We develop and implement a consistent quantum field theory framework for analysing a variety of non- equilibrium, non-perturbative phenomena associated with the Chiral Phase transition and gauge theories at finite temperature. We present a first principles calculation (within the framework of the gauged linear sigma-model) of the photon production rate during this phase transition and in the process we develop a new, improved approach towards quantum kinetics which goes far beyond standard Boltzmann-like equations. We also study the anomalous coupling of the neutral pion field to electromagnetism and find that under certain conditions, this coupling can lead to photon production via a process of parametric amplification which is intrinsically a non- perturbative phenomenon. The resulting spectrum of photons has very distinctive peaks and exhibits a polarisation asymmetry. We argue that these electromagnetic signals could be striking signatures of the Chiral Phase transition out-of-equilibrium. Motivated by certain issues associated with baryogenesis in the hot electroweak theory and with a view towards gaining an understanding of the dynamics of soft collective excitations in the Quark-Gluon Plasma, we turn our attention to the nonequilibrium dynamics of soft gauge field configurations in hot scalar QED. We argue that the dynamics of the long-wavelength excitations is determined by the Hard Thermal Loop self-energy which has the same form in both scalar QED and the non-Abelian case. We find that the relaxation of these excitations proceeds via power laws which are completely determined by the spectral density at the thresholds of Landau damping cuts. We then show that a Markovian approximation fails to describe the dynamics both at short and long times. We also introduce a new kinetic approach that goes beyond the standard Boltzmann equation by incorporating off-shell processes and find that the distribution function for soft quasiparticles relaxes with a power law
Role of non-equilibrium conformations on driven polymer translocation.
Katkar, H H; Muthukumar, M
2018-01-14
assuming a constant effective velocity of translocation, it is found that for flexible (ssDNA and synthetic) polymers with N K Kuhn segments, the condition ⟨τ⟩/N K equilibrium to non-equilibrium behavior would occur at N K ∼ O(1000).
Combined microstructure x-ray optics
International Nuclear Information System (INIS)
Barbee, T.W. Jr.
1989-02-01
Multilayers are man-made microstructures which vary in depth and are now of sufficient quality to be used as x-ray, soft x-ray and extreme ultraviolet optics. Gratings are man-made in plane microstructures which have been used as optic elements for most of this century. Joining of these two optical microstructures to form combined microstructure optical microstructures to form combined microstructure optical elements has the potential for greatly enhancing both the throughput and the resolution attainable in these spectral ranges. The characteristics of these new optic elements will be presented and compared to experiment with emphasis on the unique properties of these combined microstructures. These results reported are general in nature and not limited to the soft x-ray or extreme ultraviolet spectral domains and also apply to neutrons. 19 refs., 7 figs., 4 tabs
1982-09-01
values calculated by the first step. Similarly, appli- cation of MacCormack’s method to equation (7) for planar flow yields N N N N _N+l =N AtuN M(PLMPL...California, Los Alamos, New Mexico . 5. Bray, K. N. C., "Chemical and Vibrational Nonequilibrium in Nozzle Flows," Nonequilibrium Flows, Vol. I, Part II, ed
Stages in the energetics of baroclinic systems
Orlanski, Isidoro; Sheldon, John P.
1995-10-01
The results from several idealized and case studies are drawn together to form a comprehensive picture of "downstream baroclinic evolution" using local energetics. This new viewpoint offers a complementary alternative to the more conventional descriptions of cyclone development. These additional insights are made possible largely because the local energetics approach permits one to define an energy flux vector which accurately describes the direction of energy dispersion and quantifies the role of neighboring systems in local development. In this view, the development of a system's energetics is divided into three stages. In Stage 1, a pre-existing disturbance well upstream of an incipient trough loses energy via ageostrophic geopotential fluxes directed downstream through the intervening ridge, generating a new energy center there. In Stage 2, this new energy center grows vigorously, at first due to the convergence of these fluxes, and later by baroclinic conversion as well. As the center matures, it begins to export energy via geopotential fluxes to the eastern side of the trough, initiating yet another energy center. In Stage 3, this new energy center continues to grow while that on the western side of the trough decays due to a dwinding supply of energy via fluxes from the older upstream system and also as a consequence of its own export of energy downstream. As the eastern energy center matures, it exports energy further downstream, and the sequence begins anew. The USA "Blizzard of'93" is used as a new case study to test the limits to which this conceptual sequence might apply, as well as to augment the current limited set of case studies. It is shown that, despite the extraordinary magnitude of the event, the evolution of the trough associated with the Blizzard fits the conceptual picture of downstream baroclinic evolution quite well, with geopotential fluxes playing a critical rôle in three respects. First, fluxes from an old, decaying system in the
Trapped ion system for sympathetic cooling and non-equilibrium dynamics
Doret, Charlie; Jubin, Sierra; Stevenson, Sarah
2017-04-01
Atomic systems are superbly suited to the study of non-equilibrium dynamics. These systems' exquisite isolation from environmental perturbations leads to long relaxation times that enable exploration of far-from-equilibrium phenomena. We present progress towards trapping chains of multiple co-trapped calcium isotopes geared towards measuring thermal equilibration and sympathetic cooling rates. We also discuss plans for future experiments in non-equilibrium statistical mechanics, including exploration of the quantum-to-classical crossover between ballistic transport and diffusive, Fourier's Law conduction. This work is supported by Cottrell College Science Award from the Research Corporation for Science Advancement and by Williams College.
Frontier of plasma physics. 'Research network on non-equilibrium and extreme state plasmas'
International Nuclear Information System (INIS)
Itoh, Sanae-I.; Fujisawa, Akihide; Kodama, Ryosuke; Sato, Motoyasu; Tanaka, Kazuo A.; Hatakeyama, Rikizo; Itoh, Kimitaka
2011-01-01
Plasma physics and fusion science have been applied to a wide variety of plasmas such as nuclear fusion plasmas, high-energy-density plasmas, processing plasmas and nanobio- plasmas. They are pioneering science and technology frontiers such as new energy sources and new functional materials. A large project 'research network on non-equilibrium and extreme state plasmas' is being proposed to reassess individual plasma researches from a common view of the non-equilibrium extreme plasma and to promote collaboration among plasma researchers all over the country. In the present review, recent collaborative works related to this project are being introduced. (T.I.)
Nonequilibrium effects and structure of X-ray lines in tokamak plasma
Gontis, V. G.; Lisitsa, V. S.
1986-02-01
The sensitivity of X-ray spectra to a number of typical non-equilibrium effects occurring in modern tokamaks is examined. Experimental data from the T-10 and ST Tokamaks are cited to illustrate the degree of deviation from coronal equilibrium. The analysis exploits recent atomic data for radiation and autoionization line widths; standard semiempirical formulas are used to calculate the rates of collision processes. Ion diffusion and impurity distribution by degrees of ionization are investigated. The sensitivity of K radiation to electron nonequilibrium and ion charge exchange is examined.
One-loop calculation in time-dependent non-equilibrium thermo field dynamics
International Nuclear Information System (INIS)
Umezawa, H.; Yamanaka, Y.
1989-01-01
This paper is a review on the structure of thermo field dynamics (TFD) in which the basic concepts such as the thermal doublets, the quasi-particles and the self-consistent renormalization are presented in detail. A strong emphasis is put on the computational scheme. A detailed structure of this scheme is illustrated by the one-loop calculation in a non-equilibrium time-dependent process. A detailed account of the one-loop calculation has never been reported anywhere. The role of the self-consistent renormalization is explained. The equilibrium TFD is obtained as the long-time limit of non-equilibrium TFD. (author)
Wall ablation of heated compound-materials into non-equilibrium discharge plasmas
Wang, Weizong; Kong, Linghan; Geng, Jinyue; Wei, Fuzhi; Xia, Guangqing
2017-02-01
The discharge properties of the plasma bulk flow near the surface of heated compound-materials strongly affects the kinetic layer parameters modeled and manifested in the Knudsen layer. This paper extends the widely used two-layer kinetic ablation model to the ablation controlled non-equilibrium discharge due to the fact that the local thermodynamic equilibrium (LTE) approximation is often violated as a result of the interaction between the plasma and solid walls. Modifications to the governing set of equations, to account for this effect, are derived and presented by assuming that the temperature of the electrons deviates from that of the heavy particles. The ablation characteristics of one typical material, polytetrafluoroethylene (PTFE) are calculated with this improved model. The internal degrees of freedom as well as the average particle mass and specific heat ratio of the polyatomic vapor, which strongly depends on the temperature, pressure and plasma non-equilibrium degree and plays a crucial role in the accurate determination of the ablation behavior by this model, are also taken into account. Our assessment showed the significance of including such modifications related to the non-equilibrium effect in the study of vaporization of heated compound materials in ablation controlled arcs. Additionally, a two-temperature magneto-hydrodynamic (MHD) model accounting for the thermal non-equilibrium occurring near the wall surface is developed and applied into an ablation-dominated discharge for an electro-thermal chemical launch device. Special attention is paid to the interaction between the non-equilibrium plasma and the solid propellant surface. Both the mass exchange process caused by the wall ablation and plasma species deposition as well as the associated momentum and energy exchange processes are taken into account. A detailed comparison of the results of the non-equilibrium model with those of an equilibrium model is presented. The non-equilibrium results
Extension of CE/SE method to non-equilibrium dissociating flows
Wen, C.Y.
2017-12-08
In this study, the hypersonic non-equilibrium flows over rounded nose geometries are numerically investigated by a robust conservation element and solution element (CE/SE) code, which is based on hybrid meshes consisting of triangular and quadrilateral elements. The dissociating and recombination chemical reactions as well as the vibrational energy relaxation are taken into account. The stiff source terms are solved by an implicit trapezoidal method of integration. Comparison with laboratory and numerical cases are provided to demonstrate the accuracy and reliability of the present CE/SE code in simulating hypersonic non-equilibrium flows.
International Nuclear Information System (INIS)
Bresme, F.; Armstrong, J.
2014-01-01
We report non-equilibrium molecular dynamics simulations of heat transport in models of molecular fluids. We show that the “local” thermal conductivities obtained from non-equilibrium molecular dynamics simulations agree within numerical accuracy with equilibrium Green-Kubo computations. Our results support the local equilibrium hypothesis for transport properties. We show how to use the local dependence of the thermal gradients to quantify the thermal conductivity of molecular fluids for a wide range of thermodynamic states using a single simulation
Energy Technology Data Exchange (ETDEWEB)
Bjorgaard, J. A., E-mail: jbjorgaard@lanl.gov [Center for Nonlinear Studies, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Velizhanin, K. A. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Tretiak, S., E-mail: serg@lanl.gov [Center for Integrated Nanotechnologies, Center for Nonlinear Studies, and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2016-04-21
The effects of solvent on molecular processes such as excited state relaxation and photochemical reaction often occurs in a nonequilibrium regime. Dynamic processes such as these can be simulated using excited state molecular dynamics. In this work, we describe methods of simulating nonequilibrium solvent effects in excited state molecular dynamics using linear-response time-dependent density functional theory and apparent surface charge methods. These developments include a propagation method for solvent degrees of freedom and analytical energy gradients for the calculation of forces. Molecular dynamics of acetaldehyde in water or acetonitrile are demonstrated where the solute-solvent system is out of equilibrium due to photoexcitation and emission.
Debbichi, L.; Dappe, Y. J.; Alouani, M.
2012-01-01
The energetics and transport properties of a single aromatic molecule (C14H10) in interaction with a metallic single-walled carbon nanotube (SWCNT) have been studied using state-of-the-art density functional calculations. In both adsorption and encapsulation configurations, we show that the fundamental importance of the weak van der Waals (vdW) interactions is to stabilize the position of the molecule. These interactions have been treated through the ab initio linear combination of atomic orbitals (LCAO-S2) method including the vdW weak interactions. Moreover, we show that the electric conductance of the SWCNT, calculated within a nonequilibrium Green's-function formalism, is very sensitive to the position of the molecule with respect to the nanotube. The change of the conductance is explained in terms of charge transfer strength between the nanotube and the molecule.
Microstructure and magnetic microstructure of La + Co doped strontium hexaferrites
Energy Technology Data Exchange (ETDEWEB)
Pang Zhiyong, E-mail: pang@sdu.edu.c [School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shanda South Road 27, Jinan, Shandong 250100 (China); Zhang Xijian [School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shanda South Road 27, Jinan, Shandong 250100 (China); Ding Boming; Bao Daxin [Central Research Institute, HENGDIAN DMEGC MAGNETICS Co., LTD, Dongyang, Zhejiang 322118 (China); Han Baoshan [Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)
2010-03-04
After being cut, carefully ground, meticulously polished and properly eroded, the microstructure and magnetic microstructure of La{sub 0.3}Sr{sub 0.7}Fe{sub 11.8}Co{sub 0.2}O{sub 19} hexaferrites were investigated by using magnetic force microscopy. The shapes of a large amount of the La{sub 0.3}Sr{sub 0.7}Fe{sub 11.8}Co{sub 0.2}O{sub 19} grains were determined to be mostly irregular flat columns. The shape anisotropy of the hexaferrite grains can be explained by an abnormal grain growth process occurs for La + Co-containing hexaferrite powders. The magnetizations mainly align parallel or anti-parallel to the direction of oriented magnetic field. The magnetic domain sizes are in the same order of magnitude with the grain sizes. No complex domain structures like corrugation and spike were observed. Micromagnetic simulations were also performed to help analyzing the magnetic microstructure.
Energetic adaptations persist after bariatric surgery in severely obese adolescents
Energetic adaptations induced by bariatric surgery have not been studied in adolescents or for extended periods postsurgery. Energetic, metabolic, and neuroendocrine responses to Roux-en-Y gastric bypass (RYGB) surgery were investigated in extremely obese adolescents. At baseline and at 1.5, 6, and...
Rocket measurements of energetic particles in the midlatitude precipitation zone
Voss, H. D.; Smith, L. G.; Braswell, F. M.
1980-01-01
Measurements of energetic ion and electron properties as a function of altitude in the midlatitude zone of nighttime energetic particle precipitation are reported. The measurements of particle fluxes, energy spectra and pitch angle distributions were obtained by a Langmuir probe, six energetic particle spectrometers and an electrostatic analyzer on board a Nike Apache rocket launched near the center of the midlatitude zone during disturbed conditions. It is found that the incident flux was primarily absorbed rather than backscattered, and consists of mainly energetic hydrogen together with some helium and a small energetic electron component. Observed differential energy spectra of protons having an exponential energy spectrum, and pitch angle distributions at various altitudes indicate that the energetic particle flux decreases rapidly for pitch angles less than 70 deg. An energetic particle energy flux of 0.002 ergs/sq cm per sec is calculated which indicates the significance of energetic particles as a primary nighttime ionization source for altitudes between 120 and 200 km in the midlatitude precipitation zone.
Energetic materials: crystallization, characterization and insensitive plastic bonded explosives
Heijden, A.E.D.M. van der; Creyghton, Y.L.M.; Marino, E.; Bouma, R.H.B.; Scholtes, G.J.H.G.; Duvalois, W.; Roelands, C.P.M.
2008-01-01
The product quality of energetic materials is predominantly determined by the crystallization process applied to produce these materials. It has been demonstrated in the past that the higher the product quality of the solid energetic ingredients, the less sensitive a plastic bonded explosive
Computational studies on energetic properties of nitrogen-rich ...
Indian Academy of Sciences (India)
Computational studies on energetic properties of nitrogen-rich energetic materials with ditetrazoles. LI XIAO-HONGa,b,∗ and ZHANG RUI-ZHOUa. aCollege of Physics and Engineering, Henan University of Science and Technology, Luoyang 471 003, China. bLuoyang Key Laboratory of Photoelectric Functional Materials, ...
Energetic particles in the jovian magnetotail.
McNutt, R L; Haggerty, D K; Hill, M E; Krimigis, S M; Livi, S; Ho, G C; Gurnee, R S; Mauk, B H; Mitchell, D G; Roelof, E C; McComas, D J; Bagenal, F; Elliott, H A; Brown, L E; Kusterer, M; Vandegriff, J; Stern, S A; Weaver, H A; Spencer, J R; Moore, J M
2007-10-12
When the solar wind hits Jupiter's magnetic field, it creates a long magnetotail trailing behind the planet that channels material out of the Jupiter system. The New Horizons spacecraft traversed the length of the jovian magnetotail to >2500 jovian radii (RJ; 1 RJ identical with 71,400 kilometers), observing a high-temperature, multispecies population of energetic particles. Velocity dispersions, anisotropies, and compositional variation seen in the deep-tail (greater, similar 500 RJ) with a approximately 3-day periodicity are similar to variations seen closer to Jupiter in Galileo data. The signatures suggest plasma streaming away from the planet and injection sites in the near-tail region (approximately 200 to 400 RJ) that could be related to magnetic reconnection events. The tail structure remains coherent at least until it reaches the magnetosheath at 1655 RJ.
Energetics study of West African dust haze
International Nuclear Information System (INIS)
Omotosho, J.B.
1988-10-01
The causes of the large and often persistent negative anomalies of equivalent potential temperature observed in the 900-700 hpa layer and which occurs in association with dust haze outbreaks over Kano in winter is investigated. Energetics results indicate that the primary mechanism for such anomalies is the horizontal transport of drier and, to a lesser extent, colder air at the upper levels by eddy motions, with consequent destabilization of the atmospheric boundary layer over the station. This is suggested as the mobilization mechanism responsible for raising dust from the surface over the Bilma/Faya-Largeau source region much further poleward. Temperature inversions were also found to be more pronounced during dust spells than in clear periods. (author). 18 refs, 6 figs, 2 tabs
Baseline composition of solar energetic particles
International Nuclear Information System (INIS)
Meyer, J.
1985-01-01
We analyze all existing spacecraft observations of the highly variable heavy element composition of solar energetic particles (SEP) during non- 3 He-rich events. All data show the imprint of an ever-present basic composition pattern (dubbed ''mass-unbiased baseline'' SEP composition) that differs from the photospheric composition by a simple bias related to first ionization potential (FIP). In each particular observation, this mass-unbiased baseline composition is being distorted by an additional bias, which is always a monotonic function of mass (or Z). This latter bias varies in amplitude and even sign from observation to observation. To first order, it seems related to differences in the A/Z* ratio between elements (Z* = mean effective charge)
Flexible energetic materials and related methods
Energy Technology Data Exchange (ETDEWEB)
Heaps, Ronald J.
2018-03-06
Energetic compositions and methods of forming components from the compositions are provided. In one embodiment, a composition includes aluminum, molybdenum trioxide, potassium perchlorate, and a binder. In one embodiment, the binder may include a silicone material. The materials may be mixed with a solvent, such as xylene, de-aired, shaped and cured to provide a self-supporting structure. In one embodiment, one or more reinforcement members may be added to provide additional strength to the structure. For example, a weave or mat of carbon fiber material may be added to the mixture prior to curing. In one embodiment, blade casting techniques may be used to form a structure. In another embodiment, a structure may be formed using 3-dimensional printing techniques.
Acceleration and Propagation of Solar Energetic Particles
Klein, Karl-Ludwig; Dalla, Silvia
2017-11-01
Solar Energetic Particles (SEPs) are an important component of Space Weather, including radiation hazard to humans and electronic equipment, and the ionisation of the Earth's atmosphere. We review the key observations of SEPs, our current understanding of their acceleration and transport, and discuss how this knowledge is incorporated within Space Weather forecasting tools. Mechanisms for acceleration during solar flares and at shocks driven by Coronal Mass Ejections (CMEs) are discussed, as well as the timing relationships between signatures of solar eruptive events and the detection of SEPs in interplanetary space. Evidence on how the parameters of SEP events are related to those of the parent solar activity is reviewed and transport effects influencing SEP propagation to near-Earth locations are examined. Finally, the approaches to forecasting Space Weather SEP effects are discussed. We conclude that both flare and CME shock acceleration contribute to Space Weather relevant SEP populations and need to be considered within forecasting tools.
Energetics and population ecology of Siberian herders.
Leonard, William R; Katzmarzyk, Peter T; Crawford, Michael H
1996-01-01
Methodological advances now permit human biologists to more effectively monitor energy dynamics in traditional societies. This study examines the nutritional ecology and energetics of semisubsistence herders of Siberia (Evenki) during a single season of their annual cycle (late summer). Total energy expenditure (TEE) among adults, as measured by daily heart-rate monitoring, is greater in Evenki men (TEE = 11.9 ± 2.8 MJ/d in men and 8.8 ± 2.1 MJ/d in women; P fat distribution. Evenki males appear to be undergoing a secular trend in stature, while no such increases are evident in females. These gender differences may reflect the differential impact to the changes associated with collectivization. Reduced metabolic requirements (due to declining activity and fertility levels), along with greater food availability, are likely to be responsible for the higher rates of obesity among Evenki women. © 1996 Wiley-Liss, Inc. Copyright © 1996 Wiley-Liss, Inc.
Utilization of FEP energetics. Final report
Energy Technology Data Exchange (ETDEWEB)
Frederking, T.H.K.; Abbassi, P.; Afifi, F.; Khandhar, P.K.; Ono, D.Y.; Chen, W.E.W.
1987-12-01
The research and development work on Fountain Effect Pump Systems (FEP systems) has been of interest in the competition between mechanical pumps for He II and FEP units. The latter do not have moving parts. In the course of the work, the energetics have been addressed using one part of a simple four-changes-of-state cycle. One option is the FEP ideal change of state at constant chemical potential (mu). The other option is the two-state sequence mu-P with a d mu=0 state change followed by an isobar. Questions of pump behavior, of flow rate response to temperature difference at the hot end, and related questions of thermodynamic cycle completion and heat transfer have been addressed. Porous media data obtained elucidate differences between vapor-liquid phase separation (VLPS) and Zero Net Mass Transfer (ZNMF).
Energetic Di- and Trinitromethylpyridines: Synthesis and Characterization
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Yiying Zhang
2017-12-01
Full Text Available Pyridine derivatives based on the addition of trinitromethyl functional groups were synthesized by the reaction of N2O4 with the corresponding pyridinecarboxaldoximes, then they were converted into dinitromethylide hydrazinium salts. These energetic compounds were fully characterized by IR and NMR spectroscopy, elemental analysis, differential scanning calorimetry (DSC, and X-ray crystallography. These pyridine derivatives have good densities, positive enthalpies of formation, and acceptable sensitivity values. Theoretical calculations carried out using Gaussian 03 and EXPLO5 programs demonstrated good to excellent detonation velocities and pressures. Each of these compounds is superior in performance to TNT, while 2,6-bis(trinitromethylpyridine (D = 8700 m·s−1, P = 33.2 GPa shows comparable detonation performance to that of RDX, but its thermal stability is too low, making it inferior to RDX.
Solar energetic particles and radio burst emission
Directory of Open Access Journals (Sweden)
Miteva Rositsa
2017-01-01
Full Text Available We present a statistical study on the observed solar radio burst emission associated with the origin of in situ detected solar energetic particles. Several proton event catalogs in the period 1996–2016 are used. At the time of appearance of the particle origin (flare and coronal mass ejection we identified radio burst signatures of types II, III and IV by inspecting dynamic radio spectral plots. The information from observatory reports is also accounted for during the analysis. The occurrence of solar radio burst signatures is evaluated within selected wavelength ranges during the solar cycle 23 and the ongoing 24. Finally, we present the burst occurrence trends with respect to the intensity of the proton events and the location of their solar origin.
Solar energetic particles and radio burst emission
Miteva, Rositsa; Samwel, Susan W.; Krupar, Vratislav
2017-12-01
We present a statistical study on the observed solar radio burst emission associated with the origin of in situ detected solar energetic particles. Several proton event catalogs in the period 1996-2016 are used. At the time of appearance of the particle origin (flare and coronal mass ejection) we identified radio burst signatures of types II, III and IV by inspecting dynamic radio spectral plots. The information from observatory reports is also accounted for during the analysis. The occurrence of solar radio burst signatures is evaluated within selected wavelength ranges during the solar cycle 23 and the ongoing 24. Finally, we present the burst occurrence trends with respect to the intensity of the proton events and the location of their solar origin.
Effective charge of energetic ions in metals
International Nuclear Information System (INIS)
Kitagawa, M.; Brandt, W.
1983-01-01
The effective charge of energetic ion, as derived from stopping power of metals, is calculated by use of a dielectronic-response function method. The electronic distribution in the ion is described through the variational principle in a statistical approximation. The dependences of effective charge on the ion velocity, atomic number and r/sub s/-value of metal are derived at the low-velocity region. The effective charge becomes larger than the real charge of ion due to the close collisions. We obtain the quasi-universal equation of the fractional effective electron number of ion as a function of the ratio between the ionic size and the minimum distance approach. The comparsion between theoretical and experimental results of the effective charge is performed for the cases of N ion into Au, C and Al. We also discuss the equipartition rule of partially ionized ion at the high-velocity region
Forces and energetics of intermittent swimming
Floryan, Daniel; Van Buren, Tyler; Smits, Alexander J.
2017-08-01
Experiments are reported on intermittent swimming motions. Water tunnel experiments on a nominally two-dimensional pitching foil show that the mean thrust and power scale linearly with the duty cycle, from a value of 0.2 all the way up to continuous motions, indicating that individual bursts of activity in intermittent motions are independent of each other. This conclusion is corroborated by particle image velocimetry (PIV) flow visualizations, which show that the main vortical structures in the wake do not change with duty cycle. The experimental data also demonstrate that intermittent motions are generally energetically advantageous over continuous motions. When metabolic energy losses are taken into account, this conclusion is maintained for metabolic power fractions less than 1.
Energetic condensation growth of Nb thin films
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M. Krishnan
2012-03-01
Full Text Available This paper describes energetic condensation growth of Nb films using a cathodic arc plasma, whose 60–120 eV ions penetrate a few monolayers into the substrate and enable sufficient surface mobility to ensure that the lowest energy state (crystalline structure with minimal defects is accessible to the film. Heteroepitaxial films of Nb were grown on a-plane sapphire and MgO crystals with good superconducting properties and crystal size (10 mm×20 mm limited only by substrate size. The substrates were heated to temperatures of up to 700°C and coated at 125°C, 300°C, 500°C, and 700°C. Film thickness was varied from ∼0.25 μm to >3 μm. Residual resistivity ratio (⟨RRR⟩ values (up to a record ⟨RRR⟩=587 on MgO and ⟨RRR⟩=328 on a-sapphire depend strongly on substrate annealing and deposition temperatures. X-ray diffraction spectra and pole figures reveal that RRR increases as the crystal structure of the Nb film becomes more ordered, consistent with fewer defects and, hence, longer electron mean-free path. A transition from Nb(110 to Nb(100 orientation on the MgO(100 lattice occurs at higher temperatures. This transition is discussed in light of substrate heating and energetic condensation physics. Electron backscattered diffraction and scanning electron microscope images complement the XRD data.
International Nuclear Information System (INIS)
Hyldgaard, P
2012-01-01
The standard formulation of tunneling transport rests on an open-boundary modeling. There, conserving approximations to nonequilibrium Green function or quantum statistical mechanics provide consistent but computational costly approaches; alternatively, the use of density-dependent ballistic-transport calculations (e.g., Lang 1995 Phys. Rev. B 52 5335), here denoted ‘DBT’, provides computationally efficient (approximate) atomistic characterizations of the electron behavior but has until now lacked a formal justification. This paper presents an exact, variational nonequilibrium thermodynamic theory for fully interacting tunneling and provides a rigorous foundation for frozen-nuclei DBT calculations as a lowest-order approximation to an exact nonequilibrium thermodynamic density functional evaluation. The theory starts from the complete electron nonequilibrium quantum statistical mechanics and I identify the operator for the nonequilibrium Gibbs free energy which, generally, must be treated as an implicit solution of the fully interacting many-body dynamics. I demonstrate a minimal property of a functional for the nonequilibrium thermodynamic grand potential which thus uniquely identifies the solution as the exact nonequilibrium density matrix. I also show that the uniqueness-of-density proof from a closely related Lippmann-Schwinger collision density functional theory (Hyldgaard 2008 Phys. Rev. B 78 165109) makes it possible to express the variational nonequilibrium thermodynamic description as a single-particle formulation based on universal electron-density functionals; the full nonequilibrium single-particle formulation improves the DBT method, for example, by a more refined account of Gibbs free energy effects. I illustrate a formal evaluation of the zero-temperature thermodynamic grand potential value which I find is closely related to the variation in the scattering phase shifts and hence to Friedel density oscillations. This paper also discusses the