A class of almost equilibrium states in Robertson-Walker spacetimes

International Nuclear Information System (INIS)

Kueskue, Muharrem

2008-01-01

In quantum field theory in curved spacetimes the construction of the algebra of observables of linear fields is today well understood. However, it remains a non-trivial task to construct physically meaningful states on the algebra. For instance, we are in the unsatisfactory situation that there exist no examples of states suited to describe local thermal equilibrium in a non-stationary spacetime. In this thesis, we construct a class of states for the Klein-Gordon field in Robertson-Walker spacetimes, which seem to provide the first example of thermal states in a spacetime without time translation symmetry. More precisely, in the setting of real, linear, scalar fields in Robertson-Walker spacetimes we define on the set of homogeneous, isotropic, quasi-free states a free energy functional that is based on the averaged energy density measured by an isotropic observer along his worldline. This functional is well defined and lower bounded by a suitable quantum energy inequality. Subsequently, we minimize this functional and obtain states that we interpret as 'almost equilibrium states'. It turns out that the states of low energy are the ground states of the almost equilibrium states. Finally, we prove that the almost equilibrium states satisfy the Hadamard condition, which qualifies them as physically meaningful states. (orig.)

Phase coexistence in thin liquid films stabilized by colloidal particles: equilibrium and non-equilibrium properties

International Nuclear Information System (INIS)

Blawzdziewicz, J.; Wajnryb, E.

2005-01-01

Phase equilibria between regions of different thickness in thin liquid films stabilized by colloidal particles are investigated using a quasi-two-dimensional thermodynamic formalism. Appropriate equilibrium conditions for the film tension, normal pressure, and chemical potential of the particles in the film are formulated, and it is shown that the relaxation of these parameters occurs consecutively on three distinct time scales. Film stratification is described quantitatively for a hard-sphere suspension using a Monte-Carlo method to evaluate thermodynamic equations of state. Coexisting phases are determined for systems in constrained- and full-equilibrium states that correspond to different stages of film relaxation. We also evaluated the effective viscosity coefficients for two-dimensional compressional and shear flows of a film and the self and collective mobility coefficients of the stabilizing particles. The hydrodynamic calculations were performed using a multiple-reflection representation of Stokes flow between two free surfaces. In this approach, the particle-laden film is equivalent to a periodic system of spheres with a unit cell that is much smaller in the transverse direction than in the lateral direction. (author)

Student and school factors associated with school suspension: A multilevel analysis of students in Victoria, Australia and Washington State, United States

Science.gov (United States)

Sheryl, A. Hemphill; Stephanie, M. Plenty; Herrenkohl, Todd I.; Toumbourou, John W.; Catalano, Richard F.

2014-01-01

One of the common issues schools face is how best to handle challenging student behaviors such as violent behavior, antisocial behavior, bullying, school rule violations, and interrupting other students’ learning. School suspension may be used to remove students engaging in challenging behaviors from the school for a period of time. However, the act of suspending students from school may worsen rather than improve their behavior. Research shows that suspensions predict a range of student outcomes, including crime, delinquency, and drug use. It is therefore crucial to understand the factors associated with the use of school suspension, particularly in sites with different policy approaches to problem behaviors. This paper draws on data from state-representative samples of 3,129 Grade 7 and 9 students in Washington State, United States and Victoria, Australia sampled in 2002. Multilevel modeling examined student and school level factors associated with student-reported school suspension. Results showed that both student (being male, previous student antisocial and violent behavior, rebelliousness, academic failure) and school (socioeconomic status of the school, aggregate measures of low school commitment) level factors were associated with school suspension and that the factors related to suspension were similar in the two states. The implications of the findings for effective school behavior management policy are that, rather than focusing only on the student, both student and school level factors need to be addressed to reduce the rates of school suspension. PMID:24860205

Decomposition of thermal-equilibrium states

International Nuclear Information System (INIS)

Gu Lei

2010-01-01

It is shown that a thermal-equilibrium state can be decomposed into a tensor product of the operators in subspaces of single-particle energy. On the basis of this form, a straightforward derivation of the Fermi-Dirac and the Bose-Einstein distribution is performed. The derivation can be generalized for systems with weak interaction to obtain an approximate distribution in momentum.

State observer-based sliding mode control for semi-active hydro-pneumatic suspension

Science.gov (United States)

Ren, Hongbin; Chen, Sizhong; Zhao, Yuzhuang; Liu, Gang; Yang, Lin

2016-02-01

This paper proposes an improved virtual reference model for semi-active suspension to coordinate the vehicle ride comfort and handling stability. The reference model combines the virtues of sky-hook with ground-hook control logic, and the hybrid coefficient is tuned according to the longitudinal and lateral acceleration so as to improve the vehicle stability especially in high-speed condition. Suspension state observer based on unscented Kalman filter is designed. A sliding mode controller (SMC) is developed to track the states of the reference model. The stability of the SMC strategy is proven by means of Lyapunov function taking into account the nonlinear damper characteristics and sprung mass variation of the vehicle. Finally, the performance of the controller is demonstrated under three typical working conditions: the random road excitation, speed bump road and sharp acceleration and braking. The simulation results indicated that, compared with the traditional passive suspension, the proposed control algorithm can offer a better coordination between vehicle ride comfort and handling stability. This approach provides a viable alternative to costlier active suspension control systems for commercial vehicles.

One-group constant libraries for nuclear equilibrium state

Energy Technology Data Exchange (ETDEWEB)

Mizutani, Akihiko; Sekimoto, Hiroshi [Tokyo Inst. of Tech. (Japan). Research Lab. for Nuclear Reactors

1997-03-01

One-group constant libraries for the nuclear equilibrium state were generated for both liquid sodium cooled MOX fuel type fast reactor and PWR type thermal reactor with Equilibrium Cell Iterative Calculation System (ECICS) using JENDL-3.2, -3, -2 and ENDF/B-VI nuclear data libraries. ECICS produced one-group constant sets for 129 heavy metal nuclides and 1238 fission products. (author)

Three-dimensional stellarator equilibrium as an ohmic steady state

International Nuclear Information System (INIS)

Park, W.; Monticello, D.A.; Strauss, H.; Manickam, J.

1985-07-01

A stable three-dimensional stellarator equilibrium can be obtained numerically by a time-dependent relaxation method using small values of dissipation. The final state is an ohmic steady state which approaches an ohmic equilibrium in the limit of small dissipation coefficients. We describe a method to speed up the relaxation process and a method to implement the B vector . del p = 0 condition. These methods are applied to obtain three-dimensional heliac equilibria using the reduced heliac equations

On non-equilibrium states in QFT model with boundary interaction

International Nuclear Information System (INIS)

Bazhanov, Vladimir V.; Lukyanov, Sergei L.; Zamolodchikov, Alexander B.

1999-01-01

We prove that certain non-equilibrium expectation values in the boundary sine-Gordon model coincide with associated equilibrium-state expectation values in the systems which differ from the boundary sine-Gordon in that certain extra boundary degrees of freedom (q-oscillators) are added. Applications of this result to actual calculation of non-equilibrium characteristics of the boundary sine-Gordon model are also discussed

Near-Nash equilibrium strategies for LQ differential games with inaccurate state information

Directory of Open Access Journals (Sweden)

2006-01-01

Full Text Available ε -Nash equilibrium or “near equilibrium” for a linear quadratic cost game is considered. Due to inaccurate state information, the standard solution for feedback Nash equilibrium cannot be applied. Instead, an estimation of the players' states is substituted into the optimal control strategies equation obtained for perfect state information. The magnitude of the ε in the ε -Nash equilibrium will depend on the quality of the estimation process. To illustrate this approach, a Luenberger-type observer is used in the numerical example to generate the players' state estimates in a two-player non-zero-sum LQ differential game.

Defect Proliferation in Active Nematic Suspensions

Science.gov (United States)

Mishra, Prashant; Bowick, Mark J.; Giomi, Luca; Marchetti, M. Cristina

2014-03-01

The rich structure of equilibrium nematic suspensions, with their characteristic disclination defects, is modified when active forces come into play. The uniform nematic state is known to be unstable to splay (extensile) or bend (contractile) deformations above a critical activity. At even higher activity the flow becomes oscillatory and eventually turbulent. Using hydrodynamics, we classify the active flow regimes as functions of activity and order parameter friction for both contractile and extensile systems. The turbulent regime is marked by a non-zero steady state density of mobile defect pairs. The defect density itself scales with an ``active Ericksen number,'' defined as the ratio of the rate at which activity is injected into the system to the relaxation rate of orientational deformations. The work at Syracuse University was supported by the NSF on grant DMR-1004789 and by the Syracuse Soft Matter Program.

Structural state diagram of concentrated suspensions of jammed soft particles in oscillatory shear flow

Science.gov (United States)

Khabaz, Fardin; Cloitre, Michel; Bonnecaze, Roger T.

2018-03-01

In a recent study [Khabaz et al., Phys. Rev. Fluids 2, 093301 (2017), 10.1103/PhysRevFluids.2.093301], we showed that jammed soft particle glasses (SPGs) crystallize and order in steady shear flow. Here we investigate the rheology and microstructures of these suspensions in oscillatory shear flow using particle-dynamics simulations. The microstructures in both types of flows are similar, but their evolutions are very different. In both cases the monodisperse and polydisperse suspensions form crystalline and layered structures, respectively, at high shear rates. The crystals obtained in the oscillatory shear flow show fewer defects compared to those in the steady shear. SPGs remain glassy for maximum oscillatory strains less than about the yield strain of the material. For maximum strains greater than the yield strain, microstructural and rheological transitions occur for SPGs. Polydisperse SPGs rearrange into a layered structure parallel to the flow-vorticity plane for sufficiently high maximum shear rates and maximum strains about 10 times greater than the yield strain. Monodisperse suspensions form a face-centered cubic (FCC) structure when the maximum shear rate is low and hexagonal close-packed (HCP) structure when the maximum shear rate is high. In steady shear, the transition from a glassy state to a layered one for polydisperse suspensions included a significant induction strain before the transformation. In oscillatory shear, the transformation begins to occur immediately and with different microstructural changes. A state diagram for suspensions in large amplitude oscillatory shear flow is found to be in close but not exact agreement with the state diagram for steady shear flow. For more modest amplitudes of around one to five times the yield strain, there is a transition from a glassy structure to FCC and HCP crystals, at low and high frequencies, respectively, for monodisperse suspensions. At moderate frequencies, the transition is from glassy to HCP via

Nakedly singular non-vacuum gravitating equilibrium states

Science.gov (United States)

Woszczyna, Andrzej; Kutschera, Marek; Kubis, Sebastian; Czaja, Wojciech; Plaszczyk, Piotr; Golda, Zdzisław A.

2016-01-01

Non-vacuum static spherically symmetric spacetimes with central point-like repulsive gravity sources are investigated. Both the symmetries of spacetime and the degree of irregularity of curvature invariants, are the same as for the Schwarzschild case. The equilibrium configurations are modelled using the neutron star polytrope equation of state.

Equilibrium charge state distributions of high energy heavy ions

International Nuclear Information System (INIS)

Clark, R.B.; Grant, I.S.; King, R.; Eastham, D.A.; Joy, T.

1976-01-01

Equilibrium charge state fractions have been measured for N, O, Ne, S, Ar and Kr ions at 1.04 MeV/nucleon after passing through various stripping materials. Further data were obtained at higher energy for S ions (4.12 MeV/nucleon) and Ar ions (4.12 and 9.6 MeV/nucleon). The mean charge fractions can be fitted to universal curves for both solid and gaseous strippers. Measurements of the equilibrium fraction of krypton ions at 1.04 MeV/nucleon passing through heavy vapours have shown that a higher average charge state is obtained than for lighter gaseous strippers. (Auth.)

Dynamical behaviors of inter-out-of-equilibrium state intervals in Korean futures exchange markets

Science.gov (United States)

Lim, Gyuchang; Kim, SooYong; Kim, Kyungsik; Lee, Dong-In; Scalas, Enrico

2008-05-01

A recently discovered feature of financial markets, the two-phase phenomenon, is utilized to categorize a financial time series into two phases, namely equilibrium and out-of-equilibrium states. For out-of-equilibrium states, we analyze the time intervals at which the state is revisited. The power-law distribution of inter-out-of-equilibrium state intervals is shown and we present an analogy with discrete-time heat bath dynamics, similar to random Ising systems. In the mean-field approximation, this model reduces to a one-dimensional multiplicative process. By varying global and local model parameters, the relevance between volatilities in financial markets and the interaction strengths between agents in the Ising model are investigated and discussed.

Bifurcation and Stability Analysis of the Equilibrium States in Thermodynamic Systems in a Small Vicinity of the Equilibrium Values of Parameters

Science.gov (United States)

Barsuk, Alexandr A.; Paladi, Florentin

2018-04-01

The dynamic behavior of thermodynamic system, described by one order parameter and one control parameter, in a small neighborhood of ordinary and bifurcation equilibrium values of the system parameters is studied. Using the general methods of investigating the branching (bifurcations) of solutions for nonlinear equations, we performed an exhaustive analysis of the order parameter dependences on the control parameter in a small vicinity of the equilibrium values of parameters, including the stability analysis of the equilibrium states, and the asymptotic behavior of the order parameter dependences on the control parameter (bifurcation diagrams). The peculiarities of the transition to an unstable state of the system are discussed, and the estimates of the transition time to the unstable state in the neighborhood of ordinary and bifurcation equilibrium values of parameters are given. The influence of an external field on the dynamic behavior of thermodynamic system is analyzed, and the peculiarities of the system dynamic behavior are discussed near the ordinary and bifurcation equilibrium values of parameters in the presence of external field. The dynamic process of magnetization of a ferromagnet is discussed by using the general methods of bifurcation and stability analysis presented in the paper.

Stochastic pumping of non-equilibrium steady-states: how molecules adapt to a fluctuating environment.

Science.gov (United States)

Astumian, R D

2018-01-11

In the absence of input energy, a chemical reaction in a closed system ineluctably relaxes toward an equilibrium state governed by a Boltzmann distribution. The addition of a catalyst to the system provides a way for more rapid equilibration toward this distribution, but the catalyst can never, in and of itself, drive the system away from equilibrium. In the presence of external fluctuations, however, a macromolecular catalyst (e.g., an enzyme) can absorb energy and drive the formation of a steady state between reactant and product that is not determined solely by their relative energies. Due to the ubiquity of non-equilibrium steady states in living systems, the development of a theory for the effects of external fluctuations on chemical systems has been a longstanding focus of non-equilibrium thermodynamics. The theory of stochastic pumping has provided insight into how a non-equilibrium steady-state can be formed and maintained in the presence of dissipation and kinetic asymmetry. This effort has been greatly enhanced by a confluence of experimental and theoretical work on synthetic molecular machines designed explicitly to harness external energy to drive non-equilibrium transport and self-assembly.

A New Equilibrium State for Singly Synchronous Binary Asteroids

Science.gov (United States)

Golubov, Oleksiy; Unukovych, Vladyslav; Scheeres, Daniel J.

2018-04-01

The evolution of rotation states of small asteroids is governed by the Yarkovsky–O’Keefe–Radzievskii–Paddack (YORP) effect, nonetheless some asteroids can stop their YORP evolution by attaining a stable equilibrium. The same is true for binary asteroids subjected to the binary YORP (BYORP) effect. Here we discuss a new type of equilibrium that combines these two, which is possible in a singly synchronous binary system. This equilibrium occurs when the normal YORP, the tangential YORP, and the BYORP compensate each other, and tidal torques distribute the angular momentum between the components of the system and dissipate energy. If unperturbed, such a system would remain singly synchronous in perpetuity with constant spin and orbit rates, as the tidal torques dissipate the incoming energy from impinging sunlight at the same rate. The probability of the existence of this kind of equilibrium in a binary system is found to be on the order of a few percent.

Fluorescence lifetime components reveal kinetic intermediate states upon equilibrium denaturation of carbonic anhydrase II.

Science.gov (United States)

Nemtseva, Elena V; Lashchuk, Olesya O; Gerasimova, Marina A; Melnik, Tatiana N; Nagibina, Galina S; Melnik, Bogdan S

2017-12-21

In most cases, intermediate states of multistage folding proteins are not 'visible' under equilibrium conditions but are revealed in kinetic experiments. Time-resolved fluorescence spectroscopy was used in equilibrium denaturation studies. The technique allows for detecting changes in the conformation and environment of tryptophan residues in different structural elements of carbonic anhydrase II which in its turn has made it possible to study the intermediate states of carbonic anhydrase II under equilibrium conditions. The results of equilibrium and kinetic experiments using wild-type bovine carbonic anhydrase II and its mutant form with the substitution of leucine for alanine at position 139 (L139A) were compared. The obtained lifetime components of intrinsic tryptophan fluorescence allowed for revealing that, the same as in kinetic experiments, under equilibrium conditions the unfolding of carbonic anhydrase II ensues through formation of intermediate states.

Chemical reaction rates and non-equilibrium pressure of reacting gas mixtures in the state-to-state approach

International Nuclear Information System (INIS)

Kustova, Elena V.; Kremer, Gilberto M.

2014-01-01

Highlights: • State-to-state approach for coupled vibrational relaxation and chemical reactions. • Self-consistent model for rates of non-equilibrium reactions and energy transitions. • In viscous flows mass action law is violated. • Cross coupling between reaction rates and non-equilibrium pressure in viscous flow. • Results allow implementing the state-to-state approach for viscous flow simulations. - Abstract: Viscous gas flows with vibrational relaxation and chemical reactions in the state-to-state approach are analyzed. A modified Chapman–Enskog method is used for the determination of chemical reaction and vibrational transition rates and non-equilibrium pressure. Constitutive equations depend on the thermodynamic forces: velocity divergence and chemical reaction/transition affinity. As an application, N 2 flow with vibrational relaxation across a shock wave is investigated. Two distinct processes occur behind the shock: for small values of the distance the affinity is large and vibrational relaxation is in its initial stage; for large distances the affinity is small and the chemical reaction is in its final stage. The affinity contributes more to the transition rate than the velocity divergence and the effect of these two contributions are more important for small distances from the shock front. For the non-equilibrium pressure, the term associated with the bulk viscosity increases by a small amount the hydrostatic pressure

Chemical reaction rates and non-equilibrium pressure of reacting gas mixtures in the state-to-state approach

Energy Technology Data Exchange (ETDEWEB)

Kustova, Elena V., E-mail: e.kustova@spbu.ru [Department of Mathematics and Mechanics, Saint Petersburg State University, 198504 Universitetskiy pr. 28, Saint Petersburg (Russian Federation); Kremer, Gilberto M., E-mail: kremer@fisica.ufpr.br [Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, 81531-980 Curitiba (Brazil)

2014-12-05

Highlights: • State-to-state approach for coupled vibrational relaxation and chemical reactions. • Self-consistent model for rates of non-equilibrium reactions and energy transitions. • In viscous flows mass action law is violated. • Cross coupling between reaction rates and non-equilibrium pressure in viscous flow. • Results allow implementing the state-to-state approach for viscous flow simulations. - Abstract: Viscous gas flows with vibrational relaxation and chemical reactions in the state-to-state approach are analyzed. A modified Chapman–Enskog method is used for the determination of chemical reaction and vibrational transition rates and non-equilibrium pressure. Constitutive equations depend on the thermodynamic forces: velocity divergence and chemical reaction/transition affinity. As an application, N{sub 2} flow with vibrational relaxation across a shock wave is investigated. Two distinct processes occur behind the shock: for small values of the distance the affinity is large and vibrational relaxation is in its initial stage; for large distances the affinity is small and the chemical reaction is in its final stage. The affinity contributes more to the transition rate than the velocity divergence and the effect of these two contributions are more important for small distances from the shock front. For the non-equilibrium pressure, the term associated with the bulk viscosity increases by a small amount the hydrostatic pressure.

Equilibrium states and ground state of two-dimensional fluid foams

International Nuclear Information System (INIS)

Graner, F.; Jiang, Y.; Janiaud, E.; Flament, C.

2001-01-01

We study the equilibrium energies of two-dimensional (2D) noncoarsening fluid foams, which consist of bubbles with fixed areas. The equilibrium states correspond to local minima of the total perimeter. We present a theoretical derivation of energy minima; experiments with ferrofluid foams, which can be either highly distorted, locally relaxed, or globally annealed; and Monte Carlo simulations using the extended large-Q Potts model. For a dry foam with small size variance we develop physical insight and an electrostatic analogy, which enables us to (i) find an approximate value of the global minimum perimeter, accounting for (small) area disorder, the topological distribution, and physical boundary conditions; (ii) conjecture the corresponding pattern and topology: small bubbles sort inward and large bubbles sort outward, topological charges of the same signs ''repel'' while charges of the opposite signs ''attract;'' (iii) define local and global markers to determine directly from an image how far a foam is from its ground state; (iv) conjecture that, in a local perimeter minimum at prescribed topology, the pressure distribution and thus the edge curvature are unique. Some results also apply to 3D foams

Study on Dynamic Behaviour of Wishbone Suspension System

International Nuclear Information System (INIS)

Kamal, M; Rahman, M M

2012-01-01

This paper presents the characteristic model of the wishbone suspension system using the quarter car model approach. Suspension system in an automobile provides vehicle control and passenger comfort by providing isolation from road disturbances. This makes it essential that the detailed behavior of suspension should be known to optimize the performance. A kinetic study is performed using multi body system (MBS) analysis. The dirt road profile is considered as an applied loading. The spring constant, damping coefficient and sprung mass are studied on the performance of the suspension system. It can be observed that the spring constant is inversely related with time required to return to initial position and the amount of deformations. The damping ratio affects the suppression of spring oscillations, beyond a certain limit damping ration has the negligible effect. Sprung mass effected the equilibrium position of the suspension system with a small effect on its oscillation behavior. It is shown that the spring constant, damping ratio and sprung mass are significant parameters to design the suspension system. This study is essential for complete understanding of working of the suspension system and a future study with real geometries.

Grinding kinetics and equilibrium states

Science.gov (United States)

Opoczky, L.; Farnady, F.

1984-01-01

The temporary and permanent equilibrium occurring during the initial stage of cement grinding does not indicate the end of comminution, but rather an increased energy consumption during grinding. The constant dynamic equilibrium occurs after a long grinding period indicating the end of comminution for a given particle size. Grinding equilibrium curves can be constructed to show the stages of comminution and agglomeration for certain particle sizes.

Economically attractive features of steady-state neoclassical reversed field pinch equilibrium with low aspect ratio

International Nuclear Information System (INIS)

Shiina, S.; Yagi, Y.; Sugimoto, H.; Ashida, H.; Hirano, Y.; Koguchi, H.; Sakakita, H.; Taguchi, M.; Nagamine, Y.; Osanai, Y.; Saito, K.; Watanabe, M.; Aizawa, M.

2005-01-01

Dominant plasma self-induced current equilibrium is achieved together with the high β for the steady-state neoclassical reversed field pinch (RFP) equilibrium with low aspect ratio by broadening the plasma pressure profile. The RF-driven current, when the safety factor is smaller than unity, is much less than the self-induced current, which dominates (96%) the toroidal current. This neoclassical RFP equilibrium has strong magnetic shear or a high-stability beta (β t = 63%) due to its hollow current profile. It is shown that the obtained equilibrium is close to the relaxed-equilibrium state with a minimum energy, and is also robust against microinstabilities. These attractive features allow the economical design of compact steady-state fusion power plants with low cost of electricity (COE). (author)

Lower bounds for ballistic current and noise in non-equilibrium quantum steady states

Directory of Open Access Journals (Sweden)

Benjamin Doyon

2015-03-01

Full Text Available Let an infinite, homogeneous, many-body quantum system be unitarily evolved for a long time from a state where two halves are independently thermalized. One says that a non-equilibrium steady state emerges if there are nonzero steady currents in the central region. In particular, their presence is a signature of ballistic transport. We analyze the consequences of the current observable being a conserved density; near equilibrium this is known to give rise to linear wave propagation and a nonzero Drude peak. Using the Lieb–Robinson bound, we derive, under a certain regularity condition, a lower bound for the non-equilibrium steady-state current determined by equilibrium averages. This shows and quantifies the presence of ballistic transport far from equilibrium. The inequality suggests the definition of “nonlinear sound velocities”, which specialize to the sound velocity near equilibrium in non-integrable models, and “generalized sound velocities”, which encode generalized Gibbs thermalization in integrable models. These are bounded by the Lieb–Robinson velocity. The inequality also gives rise to a bound on the energy current noise in the case of pure energy transport. We show that the inequality is satisfied in many models where exact results are available, and that it is saturated at one-dimensional criticality.

Non-equilibrium transport in the quantum dot: quench dynamics and non-equilibrium steady state

Science.gov (United States)

Culver, Adrian; Andrei, Natan

We present an exact method of calculating the non-equilibrium current driven by a voltage drop across a quantum dot. The system is described by the two lead Anderson model at zero temperature with on-site Coulomb repulsion and non-interacting, linearized leads. We prepare the system in an initial state consisting of a free Fermi sea in each lead with the voltage drop given as the difference between the two Fermi levels. We quench the system by coupling the dot to the leads at t = 0 and following the time evolution of the wavefunction. In the long time limit a new type of Bethe Ansatz wavefunction emerges, which satisfies the Lippmann-Schwinger equation with the two Fermi seas serving as the boundary conditions. This exact, non-perturbative solution describes the non-equilibrium steady state of the system. We describe how to use this solution to compute the infinite time limit of the expectation value of the current operator at a given voltage, which would yield the I-V characteristic of the dot. Research supported by NSF Grant DMR 1410583.

34 CFR 395.17 - Suspension of designation as State licensing agency.

Science.gov (United States)

2010-07-01

... protection of Federal property on which vending machines subject to the requirements of § 395.32 are located in the State. Upon the suspension of such designation, vending machine income from vending machines... maintenance, operation and protection of the Federal property on which such vending machines are located...

Suspension Hydrogen Reduction of Iron Oxide Concentrates

Energy Technology Data Exchange (ETDEWEB)

H.Y. Sohn

2008-03-31

The objective of the project is to develop a new ironmaking technology based on hydrogen and fine iron oxide concentrates in a suspension reduction process. The ultimate objective of the new technology is to replace the blast furnace and to drastically reduce CO2 emissions in the steel industry. The goals of this phase of development are; the performance of detailed material and energy balances, thermochemical and equilibrium calculations for sulfur and phosphorus impurities, the determination of the complete kinetics of hydrogen reduction and bench-scale testing of the suspension reduction process using a large laboratory flash reactor.

Probing the equilibrium dynamics of colloidal hard spheres above the mode-coupling glass transition

NARCIS (Netherlands)

Brambilla, G.; al Masri, J.H.M.; Pierno, M.; Berthier, L.; Cipelletti, L.

2010-01-01

We use dynamic light scattering and computer simulations to study equilibrium dynamics and dynamic heterogeneity in concentrated suspensions of colloidal hard spheres. Our study covers an unprecedented density range and spans seven decades in structural relaxation time, , including equilibrium

Imaging the equilibrium state and magnetization dynamics of partially built hard disk write heads

Energy Technology Data Exchange (ETDEWEB)

Valkass, R. A. J., E-mail: rajv202@ex.ac.uk; Yu, W.; Shelford, L. R.; Keatley, P. S.; Loughran, T. H. J.; Hicken, R. J. [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Cavill, S. A. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE (United Kingdom); Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Laan, G. van der; Dhesi, S. S. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE (United Kingdom); Bashir, M. A.; Gubbins, M. A. [Research and Development, Seagate Technology, 1 Disc Drive, Springtown Industrial Estate, Derry BT48 0BF (United Kingdom); Czoschke, P. J.; Lopusnik, R. [Recording Heads Operation, Seagate Technology, 7801 Computer Avenue South, Bloomington, Minnesota 55435 (United States)

2015-06-08

Four different designs of partially built hard disk write heads with a yoke comprising four repeats of NiFe (1 nm)/CoFe (50 nm) were studied by both x-ray photoemission electron microscopy (XPEEM) and time-resolved scanning Kerr microscopy (TRSKM). These techniques were used to investigate the static equilibrium domain configuration and the magnetodynamic response across the entire structure, respectively. Simulations and previous TRSKM studies have made proposals for the equilibrium domain configuration of similar structures, but no direct observation of the equilibrium state of the writers has yet been made. In this study, static XPEEM images of the equilibrium state of writer structures were acquired using x-ray magnetic circular dichroism as the contrast mechanism. These images suggest that the crystalline anisotropy dominates the equilibrium state domain configuration, but competition with shape anisotropy ultimately determines the stability of the equilibrium state. Dynamic TRSKM images were acquired from nominally identical devices. These images suggest that a longer confluence region may hinder flux conduction from the yoke into the pole tip: the shorter confluence region exhibits clear flux beaming along the symmetry axis, whereas the longer confluence region causes flux to conduct along one edge of the writer. The observed variations in dynamic response agree well with the differences in the equilibrium magnetization configuration visible in the XPEEM images, confirming that minor variations in the geometric design of the writer structure can have significant effects on the process of flux beaming.

Emergent structures and dynamics in suspensions of self-phoretic colloids

Science.gov (United States)

Scagliarini, Andrea; Pagonabarraga, Ignacio

2013-11-01

Active fluids, such as suspensions of self-propelled particles , are a fascinating example of Soft Matter displaying complex collective behaviours which provide challenges in non-equilibrium Statistical Physics. The recent development of techniques to assemble miniaturized devices has led to a growing interest for micro and nanoscale engines that can perform autonomous motion (``microrobots''), as, for instance, self-phoretic colloids, for which the propulsion is induced by the generation of a chemical species in a reaction catalyzed at the particle surface. We perform a mesoscopic numerical study of suspensions of self-phoretic colloids. We show that, at changing the sign of the phoretic mobility (which accounts for the colloid-solute interactions), the system switches from a cluster phase to a state with slowed dynamics. We find that the cluster size distribution follows an exponential behaviour, with a characteristic size growing linearly with the colloid activity, while the density fluctuations grow as a power-law with an exponent depending on the cluster fractal dimension.We single out hydrodynamic interactions, showing that their effect is to work against cluster formation. For positive μ, we observe that colloids tend to reach an ordered state on a triangular lattice.

27 CFR 70.226 - Suspension of running of period of limitation; taxpayer outside of United States.

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2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Suspension of running of... Limitations § 70.226 Suspension of running of period of limitation; taxpayer outside of United States. The running of the period of limitations on collection after assessment prescribed in 26 U.S.C. 6502 (relating...

Phase diagram and structural evolution of tin/indium (Sn/In) nanosolder particles: from a non-equilibrium state to an equilibrium state.

Science.gov (United States)

Shu, Yang; Ando, Teiichi; Yin, Qiyue; Zhou, Guangwen; Gu, Zhiyong

2017-08-31

A binary system of tin/indium (Sn/In) in the form of nanoparticles was investigated for phase transitions and structural evolution at different temperatures and compositions. The Sn/In nanosolder particles in the composition range of 24-72 wt% In were synthesized by a surfactant-assisted chemical reduction method under ambient conditions. The morphology and microstructure of the as-synthesized nanoparticles were analyzed by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD). HRTEM and SAED identified InSn 4 and In, with some Sn being detected by XRD, but no In 3 Sn was observed. The differential scanning calorimetry (DSC) thermographs of the as-synthesized nanoparticles exhibited an endothermic peak at around 116 °C, which is indicative of the metastable eutectic melting of InSn 4 and In. When the nanosolders were subjected to heat treatment at 50-225 °C, the equilibrium phase In 3 Sn appeared while Sn disappeared. The equilibrium state was effectively attained at 225 °C. A Tammann plot of the DSC data of the as-synthesized nanoparticles indicated that the metastable eutectic composition is about 62% In, while that of the DSC data of the 225 °C heat-treated nanoparticles yielded a eutectic composition of 54% In, which confirmed the attainment of the equilibrium state at 225 °C. The phase boundaries estimated from the DSC data of heat-treated Sn/In nanosolder particles matched well with those in the established Sn-In equilibrium phase diagram. The phase transition behavior of Sn/In nanosolders leads to a new understanding of binary alloy particles at the nanoscale, and provides important information for their low temperature soldering processing and applications.

Suspension, a Wake-Up Call: Rural Educators' Attitudes toward Suspension.

Science.gov (United States)

Henderson, Joan; Friedland, Billie

Data from the West Virginia Department of Education reveals that from September 1991 to January 1992, school districts reported 18,915 out-of-school suspensions involving 12,997 students. In 1995, the West Virginia State Legislature enacted the Safe Schools Act, which specifically mandates suspension for no less than 12 consecutive months for…

76 FR 33967 - Irish Potatoes Grown in Southeastern States; Suspension of Marketing Order Provisions

Science.gov (United States)

2011-06-10

... IR] Irish Potatoes Grown in Southeastern States; Suspension of Marketing Order Provisions AGENCY... suspends the marketing order for Irish potatoes grown in Southeastern states (order), and the rules and regulations implemented thereunder, through March 1, 2014. The order regulates the handling of Irish potatoes...

The effect of time-dependent coupling on non-equilibrium steady states

DEFF Research Database (Denmark)

Cornean, Horia; Neidhardt, Hagen; Zagrebnov, Valentin

Consider (for simplicity) two one-dimensional semi-infinite leads coupled to a quantum well via time dependent point interactions. In the remote past the system is decoupled, and each of its components is at thermal equilibrium. In the remote future the system is fully coupled. We define...... and compute the non equilibrium steady state (NESS) generated by this evolution. We show that when restricted to the subspace of absolute continuity of the fully coupled system, the state does not depend at all on the switching. Moreover, we show that the stationary charge current has the same invariant...

The effect of time-dependent coupling on non-equilibrium steady states

DEFF Research Database (Denmark)

Cornean, Horia; Neidhardt, Hagen; Zagrebnov, Valentin A.

2009-01-01

Consider (for simplicity) two one-dimensional semi-infinite leads coupled to a quantum well via time dependent point interactions. In the remote past the system is decoupled, and each of its components is at thermal equilibrium. In the remote future the system is fully coupled. We define...... and compute the non equilibrium steady state (NESS) generated by this evolution. We show that when restricted to the subspace of absolute continuity of the fully coupled system, the state does not depend at all on the switching. Moreover, we show that the stationary charge current has the same invariant...

Improved understanding of the acoustophoretic focusing of dense suspensions in a microchannel

Science.gov (United States)

Karthick, S.; Sen, A. K.

2017-11-01

We provide improved understanding of acoustophoretic focusing of a dense suspension (volume fraction φ >10 % ) in a microchannel subjected to an acoustic standing wave using a proposed theoretical model and experiments. The model is based on the theory of interacting continua and utilizes a momentum transport equation for the mixture, continuity equation, and transport equation for the solid phase. The model demonstrates the interplay between acoustic radiation and shear-induced diffusion (SID) forces that is critical in the focusing of dense suspensions. The shear-induced particle migration model of Leighton and Acrivos, coupled with the acoustic radiation force, is employed to simulate the continuum behavior of particles. In the literature, various closures for the diffusion coefficient Dφ* are available for rigid spheres at high concentrations and nonspherical deformable particles [e.g., red blood cells (RBCs)] at low concentrations. Here we propose a closure for Dφ* for dense suspension of RBCs and validate the proposed model with experimental data. While the available closures for Dφ* fail to predict the acoustic focusing of a dense suspension of nonspherical deformable particles like RBCs, the predictions of the proposed model match experimental data within 15%. Both the model and experiments reveal a competition between acoustic radiation and SID forces that gives rise to an equilibrium width w* of a focused stream of particles at some distance Leq* along the flow direction. Using different shear rates, acoustic energy densities, and particle concentrations, we show that the equilibrium width is governed by Péclet number Pe and Strouhal number Stas w*=1.4(PeSt) -0.5 while the length required to obtain the equilibrium-focused width depends on St as Leq*=3.8 /(St)0.6 . The proposed model and correlations would find significance in the design of microchannels for acoustic focusing of dense suspensions such as undiluted blood.

An Active Seat Controller with Vehicle Suspension Feedforward and Feedback States: An Experimental Study

Directory of Open Access Journals (Sweden)

Abdulaziz Alfadhli

2018-04-01

Full Text Available Active seat suspensions can be used to reduce the harmful vertical vibration of a vehicle’s seat by applying an external force using a closed loop controller. Many of the controllers found in the literature are difficult to implement practically, because they are based on using unavailable or difficult and costly measurements. This paper presents both simulation and experimental studies of five novel, simple, and cost-effective control strategies to be used for an active seat suspension in order to improve ride comfort at low frequencies below 20 Hz. These strategies use available and measurable feedforward (preview information states from the vehicle secondary suspension, as well as feedback states from the seat suspension, together with gains optimised to minimise the occupant vibration. The gains were optimised using a genetic algorithm (GA, with a fitness function based on the seat effective amplitude transmissibility (SEAT factor. Constraints on the control force and the seat suspension stroke were also included in the optimisation algorithm. Simulation and laboratory experimental tests were carried out to assess the performance of the proposed controllers according to the ISO 2631-1 standard, in both the frequency and time domains with a range of different road profiles. The experimental tests were performed using a multi-axis simulation table (MAST and a physical active seat suspension configured as a hardware-in-loop (HIL simulation with a virtual linear quarter vehicle model (QvM. The results demonstrate that the proposed controllers substantially attenuate the vertical vibration at the driver’s seat compared with both a passive and a proportional-integral-derivative (PID active seat suspension and thus improve ride comfort together with reducing vibration-linked health risks. Moreover, experimental results show that employing both feedforward information and feedback vehicle body and seat acceleration signals in the controller

Computer simulations of equilibrium magnetization and microstructure in magnetic fluids

Science.gov (United States)

Rosa, A. P.; Abade, G. C.; Cunha, F. R.

2017-09-01

In this work, Monte Carlo and Brownian Dynamics simulations are developed to compute the equilibrium magnetization of a magnetic fluid under action of a homogeneous applied magnetic field. The particles are free of inertia and modeled as hard spheres with the same diameters. Two different periodic boundary conditions are implemented: the minimum image method and Ewald summation technique by replicating a finite number of particles throughout the suspension volume. A comparison of the equilibrium magnetization resulting from the minimum image approach and Ewald sums is performed by using Monte Carlo simulations. The Monte Carlo simulations with minimum image and lattice sums are used to investigate suspension microstructure by computing the important radial pair-distribution function go(r), which measures the probability density of finding a second particle at a distance r from a reference particle. This function provides relevant information on structure formation and its anisotropy through the suspension. The numerical results of go(r) are compared with theoretical predictions based on quite a different approach in the absence of the field and dipole-dipole interactions. A very good quantitative agreement is found for a particle volume fraction of 0.15, providing a validation of the present simulations. In general, the investigated suspensions are dominated by structures like dimmer and trimmer chains with trimmers having probability to form an order of magnitude lower than dimmers. Using Monte Carlo with lattice sums, the density distribution function g2(r) is also examined. Whenever this function is different from zero, it indicates structure-anisotropy in the suspension. The dependence of the equilibrium magnetization on the applied field, the magnetic particle volume fraction, and the magnitude of the dipole-dipole magnetic interactions for both boundary conditions are explored in this work. Results show that at dilute regimes and with moderate dipole

Fluctuation relations for equilibrium states with broken discrete or continuous symmetries

International Nuclear Information System (INIS)

Lacoste, D; Gaspard, P

2015-01-01

Isometric fluctuation relations are deduced for the fluctuations of the order parameter in equilibrium systems of condensed-matter physics with broken discrete or continuous symmetries. These relations are similar to their analogues obtained for non-equilibrium systems where the broken symmetry is time reversal. At equilibrium, these relations show that the ratio of the probabilities of opposite fluctuations goes exponentially with the symmetry-breaking external field and the magnitude of the fluctuations. These relations are applied to the Curie–Weiss, Heisenberg, and XY models of magnetism where the continuous rotational symmetry is broken, as well as to the q-state Potts model and the p-state clock model where discrete symmetries are broken. Broken symmetries are also considered in the anisotropic Curie–Weiss model. For infinite systems, the results are calculated using large-deviation theory. The relations are also applied to mean-field models of nematic liquid crystals where the order parameter is tensorial. Moreover, their extension to quantum systems is also deduced. (paper)

Nonlinear oscillatory rheology and structure of wormlike micellar solutions and colloidal suspensions

Science.gov (United States)

Gurnon, Amanda Kate

The complex, nonlinear flow behavior of soft materials transcends industrial applications, smart material design and non-equilibrium thermodynamics. A long-standing, fundamental challenge in soft-matter science is establishing a quantitative connection between the deformation field, local microstructure and macroscopic dynamic flow properties i.e., the rheology. Soft materials are widely used in consumer products and industrial processes including energy recovery, surfactants for personal healthcare (e.g. soap and shampoo), coatings, plastics, drug delivery, medical devices and therapeutics. Oftentimes, these materials are processed by, used during, or exposed to non-equilibrium conditions for which the transient response of the complex fluid is critical. As such, designing new dynamic experiments is imperative to testing these materials and further developing micromechanical models to predict their transient response. Two of the most common classes of these soft materials stand as the focus of the present research; they are: solutions of polymer-like micelles (PLM or also known as wormlike micelles, WLM) and concentrated colloidal suspensions. In addition to their varied applications these two different classes of soft materials are also governed by different physics. In contrast, to the shear thinning behavior of the WLMs at high shear rates, the near hard-sphere colloidal suspensions are known to display increases, sometimes quite substantial, in viscosity (known as shear thickening). The stress response of these complex fluids derive from the shear-induced microstructure, thus measurements of the microstructure under flow are critical for understanding the mechanisms underlying the complex, nonlinear rheology of these complex fluids. A popular micromechanical model is reframed from its original derivation for predicting steady shear rheology of polymers and WLMs to be applicable to weakly nonlinear oscillatory shear flow. The validity, utility and limits of

Partition Function and Configurational Entropy in Non-Equilibrium States: A New Theoretical Model

Directory of Open Access Journals (Sweden)

Akira Takada

2018-03-01

Full Text Available A new model of non-equilibrium thermodynamic states has been investigated on the basis of the fact that all thermodynamic variables can be derived from partition functions. We have thus attempted to define partition functions for non-equilibrium conditions by introducing the concept of pseudo-temperature distributions. These pseudo-temperatures are configurational in origin and distinct from kinetic (phonon temperatures because they refer to the particular fragments of the system with specific energies. This definition allows thermodynamic states to be described either for equilibrium or non-equilibrium conditions. In addition; a new formulation of an extended canonical partition function; internal energy and entropy are derived from this new temperature definition. With this new model; computational experiments are performed on simple non-interacting systems to investigate cooling and two distinct relaxational effects in terms of the time profiles of the partition function; internal energy and configurational entropy.

An equilibrium for frustrated quantum spin systems in the stochastic state selection method

International Nuclear Information System (INIS)

Munehisa, Tomo; Munehisa, Yasuko

2007-01-01

We develop a new method to calculate eigenvalues in frustrated quantum spin models. It is based on the stochastic state selection (SSS) method, which is an unconventional Monte Carlo technique that we have investigated in recent years. We observe that a kind of equilibrium is realized under some conditions when we repeatedly operate a Hamiltonian and a random choice operator, which is defined by stochastic variables in the SSS method, to a trial state. In this equilibrium, which we call the SSS equilibrium, we can evaluate the lowest eigenvalue of the Hamiltonian using the statistical average of the normalization factor of the generated state. The SSS equilibrium itself has already been observed in unfrustrated models. Our study in this paper shows that we can also see the equilibrium in frustrated models, with some restriction on values of a parameter introduced in the SSS method. As a concrete example, we employ the spin-1/2 frustrated J 1 -J 2 Heisenberg model on the square lattice. We present numerical results on the 20-, 32-, and 36-site systems, which demonstrate that statistical averages of the normalization factors reproduce the known exact eigenvalue to good precision. Finally, we apply the method to the 40-site system. Then we obtain the value of the lowest energy eigenvalue with an error of less than 0.2%

Equilibrium states of nonsynchronous stars in detached binaries

International Nuclear Information System (INIS)

Lubow, S.H.

1979-01-01

The effects of nonsynchronous spin on equilibrium states for the radiative envelopes of detached members of close binaries are analyzed. With the adoption of the assumption that the nonsynchronous speeds, u, are much less than the relative orbital speed, Ωd, of the component stars, the full set of stellar structure equations, generalized to include the gas dynamical and heat transport effects of spin, are analyzed to linear order in u/Ωd. For these equilibria: (2) from this velocity field isobars and hence stellar shapes can be calculated for equilibrium states of slightly nonsynchronously rotating stars. On the orbit plane these surfaces coincide with the Roche equipotentials. (3) All sightly nonsynchronous equilibria are baroclinic. Isodensities and isotherms are inclined to isobars by an angle on the order of 0 0 .3 x (u/Ωd for a star in quasi-rigid rotation that nearly fills its Roche lobe). (4) The surface flux distribution departs from the usual gravity darkening law by an amount that scales with u/Ωd. Comparisons of this work are made with the results of previous investigations, and possibilities for future investigations are discussed

Physical mechanism for biopolymers to aggregate and maintain in non-equilibrium states.

Science.gov (United States)

Ma, Wen-Jong; Hu, Chin-Kun

2017-06-08

Many human or animal diseases are related to aggregation of proteins. A viable biological organism should maintain in non-equilibrium states. How protein aggregate and why biological organisms can maintain in non-equilibrium states are not well understood. As a first step to understand such complex systems problems, we consider simple model systems containing polymer chains and solvent particles. The strength of the spring to connect two neighboring monomers in a polymer chain is controlled by a parameter s with s → ∞ for rigid-bond. The strengths of bending and torsion angle dependent interactions are controlled by a parameter s A with s A  → -∞ corresponding to no bending and torsion angle dependent interactions. We find that for very small s A , polymer chains tend to aggregate spontaneously and the trend is independent of the strength of spring. For strong springs, the speed distribution of monomers in the parallel (along the direction of the spring to connect two neighboring monomers) and perpendicular directions have different effective temperatures and such systems are in non-equilibrium states.

Incorporation of a Chemical Equilibrium Equation of State into LOCI-Chem

Science.gov (United States)

Cox, Carey F.

2005-01-01

Renewed interest in development of advanced high-speed transport, reentry vehicles and propulsion systems has led to a resurgence of research into high speed aerodynamics. As this flow regime is typically dominated by hot reacting gaseous flow, efficient models for the characteristic chemical activity are necessary for accurate and cost effective analysis and design of aerodynamic vehicles that transit this regime. The LOCI-Chem code recently developed by Ed Luke at Mississippi State University for NASA/MSFC and used by NASA/MSFC and SSC represents an important step in providing an accurate, efficient computational tool for the simulation of reacting flows through the use of finite-rate kinetics [3]. Finite rate chemistry however, requires the solution of an additional N-1 species mass conservation equations with source terms involving reaction kinetics that are not fully understood. In the equilibrium limit, where the reaction rates approach infinity, these equations become very stiff. Through the use of the assumption of local chemical equilibrium the set of governing equations is reduced back to the usual gas dynamic equations, and thus requires less computation, while still allowing for the inclusion of reacting flow phenomenology. The incorporation of a chemical equilibrium equation of state module into the LOCI-Chem code was the primary objective of the current research. The major goals of the project were: (1) the development of a chemical equilibrium composition solver, and (2) the incorporation of chemical equilibrium solver into LOCI-Chem. Due to time and resource constraints, code optimization was not considered unless it was important to the proper functioning of the code.

SRB states and nonequilibrium statistical mechanics close to equilibrium

OpenAIRE

Gallavotti, Giovannni; Ruelle, David

1996-01-01

Nonequilibrium statistical mechanics close to equilibrium is studied using SRB states and a formula for their derivatives with respect to parameters. We write general expressions for the thermodynamic fluxes (or currents) and the transport coefficients, generalizing previous results. In this framework we give a general proof of the Onsager reciprocity relations.

The equation of state and ionization equilibrium of dense aluminum plasma with conductivity verification

International Nuclear Information System (INIS)

Wang, Kun; Shi, Zongqian; Shi, Yuanjie; Bai, Jun; Wu, Jian; Jia, Shenli

2015-01-01

The equation of state, ionization equilibrium, and conductivity are the most important parameters for investigation of dense plasma. The equation of state is calculated with the non-ideal effects taken into consideration. The electron chemical potential and pressure, which are commonly used thermodynamic quantities, are calculated by the non-ideal free energy and compared with results of a semi-empirical equation of state based on Thomas-Fermi-Kirzhnits model. The lowering of ionization potential, which is a crucial factor in the calculation of non-ideal Saha equation, is settled according to the non-ideal free energy. The full coupled non-ideal Saha equation is applied to describe the ionization equilibrium of dense plasma. The conductivity calculated by the Lee-More-Desjarlais model combined with non-ideal Saha equation is compared with experimental data. It provides a possible approach to verify the accuracy of the equation of state and ionization equilibrium

Non-equilibrium supramolecular polymerization.

Science.gov (United States)

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.

Non-equilibrium oxidation states of zirconium during early stages of metal oxidation

International Nuclear Information System (INIS)

Ma, Wen; Yildiz, Bilge; Herbert, F. William; Senanayake, Sanjaya D.

2015-01-01

The chemical state of Zr during the initial, self-limiting stage of oxidation on single crystal zirconium (0001), with oxide thickness on the order of 1 nm, was probed by synchrotron x-ray photoelectron spectroscopy. Quantitative analysis of the Zr 3d spectrum by the spectrum reconstruction method demonstrated the formation of Zr 1+ , Zr 2+ , and Zr 3+ as non-equilibrium oxidation states, in addition to Zr 4+ in the stoichiometric ZrO 2 . This finding resolves the long-debated question of whether it is possible to form any valence states between Zr 0 and Zr 4+ at the metal-oxide interface. The presence of local strong electric fields and the minimization of interfacial energy are assessed and demonstrated as mechanisms that can drive the formation of these non-equilibrium valence states of Zr

Actuated rheology of magnetic micro-swimmers suspensions: Emergence of motor and brake states

Science.gov (United States)

Vincenti, Benoit; Douarche, Carine; Clement, Eric

2018-03-01

We study the effect of magnetic field on the rheology of magnetic micro-swimmers suspensions. We use a model of a dilute suspension under simple shear and subjected to a constant magnetic field. Particle shear stress is obtained for both pusher and puller types of micro-swimmers. In the limit of low shear rate, the rheology exhibits a constant shear stress, called actuated stress, which only depends on the swimming activity of the particles. This stress is induced by the magnetic field and can be positive (brake state) or negative (motor state). In the limit of low magnetic fields, a scaling relation of the motor-brake effect is derived as a function of the dimensionless parameters of the model. In this case, the shear stress is an affine function of the shear rate. The possibilities offered by such an active system to control the rheological response of a fluid are finally discussed.

Equilibrium points of the tilted perfect fluid Bianchi VIh state space

Science.gov (United States)

Apostolopoulos, Pantelis S.

2005-05-01

We present the full set of evolution equations for the spatially homogeneous cosmologies of type VIh filled with a tilted perfect fluid and we provide the corresponding equilibrium points of the resulting dynamical state space. It is found that only when the group parameter satisfies h > -1 a self-similar solution exists. In particular we show that for h > -{1/9} there exists a self-similar equilibrium point provided that γ ∈ ({2(3+sqrt{-h})/5+3sqrt{-h}},{3/2}) whereas for h VIh.

Temperature in non-equilibrium states: a review of open problems and current proposals

International Nuclear Information System (INIS)

Casas-Vazquez, J; Jou, D

2003-01-01

The conceptual problems arising in the definition and measurement of temperature in non-equilibrium states are discussed in this paper in situations where the local-equilibrium hypothesis is no longer satisfactory. This is a necessary and urgent discussion because of the increasing interest in thermodynamic theories beyond local equilibrium, in computer simulations, in non-linear statistical mechanics, in new experiments, and in technological applications of nanoscale systems and material sciences. First, we briefly review the concept of temperature from the perspectives of equilibrium thermodynamics and statistical mechanics. Afterwards, we explore which of the equilibrium concepts may be extrapolated beyond local equilibrium and which of them should be modified, then we review several attempts to define temperature in non-equilibrium situations from macroscopic and microscopic bases. A wide review of proposals is offered on effective non-equilibrium temperatures and their application to ideal and real gases, electromagnetic radiation, nuclear collisions, granular systems, glasses, sheared fluids, amorphous semiconductors and turbulent fluids. The consistency between the different relativistic transformation laws for temperature is discussed in the new light gained from this perspective. A wide bibliography is provided in order to foster further research in this field

Equilibrium solubility measurement of ionizable drugs – consensus recommendations for improving data quality

Directory of Open Access Journals (Sweden)

Alex Avdeef

2016-06-01

Full Text Available This commentary addresses data quality in equilibrium solubility measurement in aqueous solution. Broadly discussed is the “gold standard” shake-flask (SF method used to measure equilibrium solubility of ionizable drug-like molecules as a function of pH. Many factors affecting the quality of the measurement are recognized. Case studies illustrating the analysis of both solution and solid state aspects of solubility measurement are presented. Coverage includes drug aggregation in solution (sub-micellar, micellar, complexation, use of mass spectrometry to assess aggregation in saturated solutions, solid state characterization (salts, polymorphs, cocrystals, polymorph creation by potentiometric method, solubility type (water, buffer, intrinsic, temperature, ionic strength, pH measurement, buffer issues, critical knowledge of the pKa, equilibration time (stirring and sedimentation, separating solid from saturated solution, solution handling and adsorption to untreated surfaces, solubility units, and tabulation/graphic presentation of reported data. The goal is to present cohesive recommendations that could lead to better assay design, to result in improved quality of measurements, and to impart a deeper understanding of the underlying solution chemistry in suspensions of drug solids.

Influence of neural adaptation on dynamics and equilibrium state of neural activities in a ring neural network

Science.gov (United States)

Takiyama, Ken

2017-12-01

How neural adaptation affects neural information processing (i.e. the dynamics and equilibrium state of neural activities) is a central question in computational neuroscience. In my previous works, I analytically clarified the dynamics and equilibrium state of neural activities in a ring-type neural network model that is widely used to model the visual cortex, motor cortex, and several other brain regions. The neural dynamics and the equilibrium state in the neural network model corresponded to a Bayesian computation and statistically optimal multiple information integration, respectively, under a biologically inspired condition. These results were revealed in an analytically tractable manner; however, adaptation effects were not considered. Here, I analytically reveal how the dynamics and equilibrium state of neural activities in a ring neural network are influenced by spike-frequency adaptation (SFA). SFA is an adaptation that causes gradual inhibition of neural activity when a sustained stimulus is applied, and the strength of this inhibition depends on neural activities. I reveal that SFA plays three roles: (1) SFA amplifies the influence of external input in neural dynamics; (2) SFA allows the history of the external input to affect neural dynamics; and (3) the equilibrium state corresponds to the statistically optimal multiple information integration independent of the existence of SFA. In addition, the equilibrium state in a ring neural network model corresponds to the statistically optimal integration of multiple information sources under biologically inspired conditions, independent of the existence of SFA.

Usefulness of an equal-probability assumption for out-of-equilibrium states: A master equation approach

KAUST Repository

Nogawa, Tomoaki

2012-10-18

We examine the effectiveness of assuming an equal probability for states far from equilibrium. For this aim, we propose a method to construct a master equation for extensive variables describing nonstationary nonequilibrium dynamics. The key point of the method is the assumption that transient states are equivalent to the equilibrium state that has the same extensive variables, i.e., an equal probability holds for microscopic states in nonequilibrium. We demonstrate an application of this method to the critical relaxation of the two-dimensional Potts model by Monte Carlo simulations. While the one-variable description, which is adequate for equilibrium, yields relaxation dynamics that are very fast, the redundant two-variable description well reproduces the true dynamics quantitatively. These results suggest that some class of the nonequilibrium state can be described with a small extension of degrees of freedom, which may lead to an alternative way to understand nonequilibrium phenomena. © 2012 American Physical Society.

Usefulness of an equal-probability assumption for out-of-equilibrium states: A master equation approach

KAUST Repository

Nogawa, Tomoaki; Ito, Nobuyasu; Watanabe, Hiroshi

2012-01-01

We examine the effectiveness of assuming an equal probability for states far from equilibrium. For this aim, we propose a method to construct a master equation for extensive variables describing nonstationary nonequilibrium dynamics. The key point of the method is the assumption that transient states are equivalent to the equilibrium state that has the same extensive variables, i.e., an equal probability holds for microscopic states in nonequilibrium. We demonstrate an application of this method to the critical relaxation of the two-dimensional Potts model by Monte Carlo simulations. While the one-variable description, which is adequate for equilibrium, yields relaxation dynamics that are very fast, the redundant two-variable description well reproduces the true dynamics quantitatively. These results suggest that some class of the nonequilibrium state can be described with a small extension of degrees of freedom, which may lead to an alternative way to understand nonequilibrium phenomena. © 2012 American Physical Society.

Impacts of energy consumption and emissions on the trip cost without late arrival at the equilibrium state

Science.gov (United States)

Tang, Tie-Qiao; Wang, Tao; Chen, Liang; Shang, Hua-Yan

2017-08-01

In this paper, we apply a car-following model, fuel consumption model, emission model and electricity consumption model to explore the influences of energy consumption and emissions on each commuter's trip costs without late arrival at the equilibrium state. The numerical results show that the energy consumption and emissions have significant impacts on each commuter's trip cost without late arrival at the equilibrium state. The fuel cost and emission cost prominently enhance each commuter's trip cost and the trip cost increases with the number of vehicles, which shows that considering the fuel cost and emission cost in the trip cost will destroy the equilibrium state. However, the electricity cost slightly enhances each commuter's trip cost, but the trip cost is still approximately a constant, which indicates that considering the electricity cost in the trip cost does not destroy the equilibrium state.

Infinite-mode squeezed coherent states and non-equilibrium statistical mechanics (phase-space-picture approach)

International Nuclear Information System (INIS)

Yeh, L.

1992-01-01

The phase-space-picture approach to quantum non-equilibrium statistical mechanics via the characteristic function of infinite- mode squeezed coherent states is introduced. We use quantum Brownian motion as an example to show how this approach provides an interesting geometrical interpretation of quantum non-equilibrium phenomena

The Donnan equilibrium: I. On the thermodynamic foundation of the Donnan equation of state

NARCIS (Netherlands)

Philipse, A.P.; Vrij, A.

2011-01-01

The thermodynamic equilibrium between charged colloids and an electrolyte reservoir is named after Frederic Donnan who first published on it one century ago (Donnan 1911 Z. Electrochem. 17 572). One of the intriguing features of the Donnan equilibrium is the ensuing osmotic equation of state which

Adaptive behaviour and multiple equilibrium states in a predator-prey model.

Science.gov (United States)

Pimenov, Alexander; Kelly, Thomas C; Korobeinikov, Andrei; O'Callaghan, Michael J A; Rachinskii, Dmitrii

2015-05-01

There is evidence that multiple stable equilibrium states are possible in real-life ecological systems. Phenomenological mathematical models which exhibit such properties can be constructed rather straightforwardly. For instance, for a predator-prey system this result can be achieved through the use of non-monotonic functional response for the predator. However, while formal formulation of such a model is not a problem, the biological justification for such functional responses and models is usually inconclusive. In this note, we explore a conjecture that a multitude of equilibrium states can be caused by an adaptation of animal behaviour to changes of environmental conditions. In order to verify this hypothesis, we consider a simple predator-prey model, which is a straightforward extension of the classic Lotka-Volterra predator-prey model. In this model, we made an intuitively transparent assumption that the prey can change a mode of behaviour in response to the pressure of predation, choosing either "safe" of "risky" (or "business as usual") behaviour. In order to avoid a situation where one of the modes gives an absolute advantage, we introduce the concept of the "cost of a policy" into the model. A simple conceptual two-dimensional predator-prey model, which is minimal with this property, and is not relying on odd functional responses, higher dimensionality or behaviour change for the predator, exhibits two stable co-existing equilibrium states with basins of attraction separated by a separatrix of a saddle point. Copyright © 2015 Elsevier Inc. All rights reserved.

Monte Carlo modeling of Lead-Cooled Fast Reactor in adiabatic equilibrium state

Energy Technology Data Exchange (ETDEWEB)

Stanisz, Przemysław, E-mail: pstanisz@agh.edu.pl; Oettingen, Mikołaj, E-mail: moettin@agh.edu.pl; Cetnar, Jerzy, E-mail: cetnar@mail.ftj.agh.edu.pl

2016-05-15

Graphical abstract: - Highlights: • We present the Monte Carlo modeling of the LFR in the adiabatic equilibrium state. • We assess the adiabatic equilibrium fuel composition using the MCB code. • We define the self-adjusting process of breeding gain by the control rod operation. • The designed LFR can work in the adiabatic cycle with zero fuel breeding. - Abstract: Nuclear power would appear to be the only energy source able to satisfy the global energy demand while also achieving a significant reduction of greenhouse gas emissions. Moreover, it can provide a stable and secure source of electricity, and plays an important role in many European countries. However, nuclear power generation from its birth has been doomed by the legacy of radioactive nuclear waste. In addition, the looming decrease in the available resources of fissile U235 may influence the future sustainability of nuclear energy. The integrated solution to both problems is not trivial, and postulates the introduction of a closed-fuel cycle strategy based on breeder reactors. The perfect choice of a novel reactor system fulfilling both requirements is the Lead-Cooled Fast Reactor operating in the adiabatic equilibrium state. In such a state, the reactor converts depleted or natural uranium into plutonium while consuming any self-generated minor actinides and transferring only fission products as waste. We present the preliminary design of a Lead-Cooled Fast Reactor operating in the adiabatic equilibrium state with the Monte Carlo Continuous Energy Burnup Code – MCB. As a reference reactor model we apply the core design developed initially under the framework of the European Lead-cooled SYstem (ELSY) project and refined in the follow-up Lead-cooled European Advanced DEmonstration Reactor (LEADER) project. The major objective of the study is to show to what extent the constraints of the adiabatic cycle are maintained and to indicate the phase space for further improvements. The analysis

Local thermal equilibrium and KMS states in curved spacetime

International Nuclear Information System (INIS)

Solveen, Christoph

2012-01-01

On the example of a free massless and conformally coupled scalar field, it is argued that in quantum field theory in curved spacetimes with the time-like Killing field, the corresponding KMS states (generalized Gibbs ensembles) at parameter β > 0 need not possess a definite temperature in the sense of the zeroth law. In fact, these states, although passive in the sense of the second law, are not always in local thermal equilibrium (LTE). A criterion characterizing LTE states with sharp local temperature is discussed. Moreover, a proposal is made for fixing the renormalization freedom of composite fields which serve as ‘thermal observables’ and a new definition of the thermal energy of LTE states is introduced. Based on these results, a general relation between the local temperature and the parameter β is established for KMS states in (anti) de Sitter spacetime. (paper)

76 FR 65360 - Irish Potatoes Grown in Southeastern States; Suspension of Marketing Order Provisions

Science.gov (United States)

2011-10-21

... operate without marketing order requirements in order to review the effectiveness of the order. During the... DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 953 [Doc. No. AMS-FV-11-0027; FV11-953-1 FR] Irish Potatoes Grown in Southeastern States; Suspension of Marketing Order Provisions...

Application of ultra-small-angle X-ray scattering / X-ray photon correlation spectroscopy to relate equilibrium or non-equilibrium dynamics to microstructure

Science.gov (United States)

Allen, Andrew; Zhang, Fan; Levine, Lyle; Ilavsky, Jan

2013-03-01

Ultra-small-angle X-ray scattering (USAXS) can probe microstructures over the nanometer-to-micrometer scale range. Through use of a small instrument entrance slit, X-ray photon correlation spectroscopy (XPCS) exploits the partial coherence of an X-ray synchrotron undulator beam to provide unprecedented sensitivity to the dynamics of microstructural change. In USAXS/XPCS studies, the dynamics of local structures in a scale range of 100 nm to 1000 nm can be related to an overall hierarchical microstructure extending from 1 nm to more than 1000 nm. Using a point-detection scintillator mode, the equilibrium dynamics at ambient temperature of small particles (which move more slowly than nanoparticles) in aqueous suspension have been quantified directly for the first time. Using a USAXS-XPCS scanning mode for non-equilibrium dynamics incipient processes within dental composites have been elucidated, prior to effects becoming detectable using any other technique. Use of the Advanced Photon Source, an Office of Science User Facility operated for the United States Department of Energy (U.S. DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under Contract No. DE-AC02-06CH11357.

Non-homogeneous flow profiles in sheared bacterial suspensions

Science.gov (United States)

Samanta, Devranjan; Cheng, Xiang

Bacterial suspensions under shear exhibit interesting rheological behaviors including the remarkable ``superfluidic'' state with vanishing viscosity at low shear rates. Theoretical studies have shown that such ``superfluidic'' state is linked with non-homogeneous shear flows, which are induced by coupling between nematic order of active fluids and hydrodynamics of shear flows. However, although bulk rheology of bacterial suspensions has been experimentally studied, shear profiles within bacterial suspensions have not been explored so far. Here, we experimentally investigate the flow behaviors of E. coli suspensions under planar oscillatory shear. Using confocal microscopy and PIV, we measure velocity profiles across gap between two shear plates. We find that with increasing shear rates, high-concentration bacterial suspensions exhibit an array of non-homogeneous flow behaviors like yield-stress flows and shear banding. We show that these non-homogeneous flows are due to collective motion of bacterial suspensions. The phase diagram of sheared bacterial suspensions is systematically mapped as functions of shear rates an bacterial concentrations. Our experiments provide new insights into rheology of bacterial suspensions and shed light on shear induced dynamics of active fluids. Chemical Engineering and Material Science department.

Mental Equilibrium and Rational Emotions

OpenAIRE

Eyal Winter; Ignacio Garcia-Jurado; Jose Mendez-Naya; Luciano Mendez-Naya

2009-01-01

We introduce emotions into an equilibrium notion. In a mental equilibrium each player "selects" an emotional state which determines the player's preferences over the outcomes of the game. These preferences typically differ from the players' material preferences. The emotional states interact to play a Nash equilibrium and in addition each player's emotional state must be a best response (with respect to material preferences) to the emotional states of the others. We discuss the concept behind...

Influence of collective excitations on pre-equilibrium and equilibrium processes

International Nuclear Information System (INIS)

Ignatyuk, A.V.; Lunev, V.P.

1990-01-01

The influence of the collective states excitations on equilibrium and preequilibrium processes in reaction is discussed. It is shown that for a consistent description of the contribution of preequilibrium and equilibrium compound processes collective states should be taken into account in the level density calculations. The microscopic and phenomenological approaches for the level density calculations are discussed. 13 refs.; 8 figs

Quantized levitation states of superconducting multiple-ring systems

International Nuclear Information System (INIS)

Haley, S.B.; Fink, H.J.

1996-01-01

The quantized levitation, trapped, and suspension states of a magnetic microsphere held in equilibrium by two fixed superconducting (SC) microrings are calculated by minimizing the free energy of the system. Each state is a discrete function of two independent fluxoid quantum numbers of the rings. When the radii of the SC rings are of the same order as the Ginzburg-Landau coherence length ξ(T), the system exhibits a small set of gravity and temperature-dependent levels. The levels of a weakly magnetized particle are sensitive functions of the gravitational field, indicating potential application as an accelerometer, and for trapping small magnetic particles in outer space or on Earth. The equilibrium states of a SC ring levitated by another SC ring are also calculated. copyright 1996 The American Physical Society

Equilibrium state of a cylindrical particle with flat ends in nematic liquid crystals.

Science.gov (United States)

Hashemi, S Masoomeh; Ejtehadi, Mohammad Reza

2015-01-01

A continuum theory is employed to numerically study the equilibrium orientation and defect structures of a circular cylindrical particle with flat ends under a homeotropic anchoring condition in a uniform nematic medium. Different aspect ratios of this colloidal geometry from thin discotic to long rodlike shapes and several colloidal length scales ranging from mesoscale to nanoscale are investigated. We show that the equilibrium state of this colloidal geometry is sensitive to the two geometrical parameters: aspect ratio and length scale of the particle. For a large enough mesoscopic particle, there is a specific asymptotic equilibrium angle associated to each aspect ratio. Upon reducing the particle size to nanoscale, the equilibrium angle follows a descending or ascending trend in such a way that the equilibrium angle of a particle with the aspect ratio bigger than 1:1 (a discotic particle) goes to a parallel alignment with respect to the far-field nematic, whereas the equilibrium angle for a particle with the aspect ratio 1:1 and smaller (a rodlike particle) tends toward a perpendicular alignment to the uniform nematic direction. The discrepancy between the equilibrium angles of the mesoscopic and nanoscopic particles originates from the significant differences between their defect structures. The possible defect structures related to mesoscopic and nanoscopic colloidal particles of this geometry are also introduced.

Osmotic consolidation of suspensions and gels

International Nuclear Information System (INIS)

Miller, K.T.; Zukoski, C.F.

1994-01-01

An osmotic method for the consolidation of suspensions of ceramic particles is demonstrated. Concentrated solutions of poly(ethylene oxide) are separated from a suspension of ceramic particles by a semipermeable membrane, creating a gradient in solvent chemical potential. Solvent passes from the suspension into the polymer solution, lowering its free energy and consolidating the suspension. Dispersions of stable 8-nm hydrous zirconia particles were consolidated to over 47% by volume. Suspensions of α-alumina in three states of aggregation (dispersed, weakly flocculated, and strongly flocculated) were consolidated to densities greater than or equal to those produced in conventional pressure filtration. Moreover, the as-consolidated alumina bodies were partially drained of fluid during the osmotic consolidation process, producing cohesive partially dried bodies with improved handling characteristics

Decoupling Suspension Controller Based on Magnetic Flux Feedback

Directory of Open Access Journals (Sweden)

Wenqing Zhang

2013-01-01

Full Text Available The suspension module control system model has been established based on MIMO (multiple input and multiple output state feedback linearization. We have completed decoupling between double suspension points, and the new decoupling method has been applied to CMS04 magnetic suspension vehicle in national mid-low-speed maglev experiment field of Tangshan city in China. Double suspension system model is very accurate for investigating stability property of maglev control system. When magnetic flux signal is taken back to the suspension control system, the suspension module’s antijamming capacity for resisting suspension load variety has been proved. Also, the external force interference has been enhanced. As a result, the robustness and stability properties of double-electromagnet suspension control system have been enhanced.

Decoupling suspension controller based on magnetic flux feedback.

Science.gov (United States)

Zhang, Wenqing; Li, Jie; Zhang, Kun; Cui, Peng

2013-01-01

The suspension module control system model has been established based on MIMO (multiple input and multiple output) state feedback linearization. We have completed decoupling between double suspension points, and the new decoupling method has been applied to CMS04 magnetic suspension vehicle in national mid-low-speed maglev experiment field of Tangshan city in China. Double suspension system model is very accurate for investigating stability property of maglev control system. When magnetic flux signal is taken back to the suspension control system, the suspension module's antijamming capacity for resisting suspension load variety has been proved. Also, the external force interference has been enhanced. As a result, the robustness and stability properties of double-electromagnet suspension control system have been enhanced.

Stability analysis of the endemic equilibrium state of an infection age ...

African Journals Online (AJOL)

In this work we present an infection-age-structured mathematical model of AIDS disease dynamics and examine the endemic equilibrium state for stability. An explicit formula for the basic reproduction number R0 was obtained in terms of the demographic and epidemiological parameters of the model. The endemic ...

Simplified Analytical Method for Optimized Initial Shape Analysis of Self-Anchored Suspension Bridges and Its Verification

Directory of Open Access Journals (Sweden)

Myung-Rag Jung

2015-01-01

Full Text Available A simplified analytical method providing accurate unstrained lengths of all structural elements is proposed to find the optimized initial state of self-anchored suspension bridges under dead loads. For this, equilibrium equations of the main girder and the main cable system are derived and solved by evaluating the self-weights of cable members using unstrained cable lengths and iteratively updating both the horizontal tension component and the vertical profile of the main cable. Furthermore, to demonstrate the validity of the simplified analytical method, the unstrained element length method (ULM is applied to suspension bridge models based on the unstressed lengths of both cable and frame members calculated from the analytical method. Through numerical examples, it is demonstrated that the proposed analytical method can indeed provide an optimized initial solution by showing that both the simplified method and the nonlinear FE procedure lead to practically identical initial configurations with only localized small bending moment distributions.

Structural analysis of compression helical spring used in suspension system

Science.gov (United States)

Jain, Akshat; Misra, Sheelam; Jindal, Arun; Lakhian, Prateek

2017-07-01

The main aim of this work has to develop a helical spring for shock absorber used in suspension system which is designed to reduce shock impulse and liberate kinetic energy. In a vehicle, it increases comfort by decreasing amplitude of disturbances and it improves ride quality by absorbing and dissipating energy. When a vehicle is in motion on a road and strikes a bump, spring comes into action quickly. After compression, spring will attempt to come to its equilibrium state which is on level road. Helical springs can be made lighter with more strength by reducing number of coils and increasing the area. In this research work, a helical spring is modeled and analyzed to substitute the existing steel spring which is used in suspension. By using different materials, stress and deflection of helical spring can be varied. Comparability between existing spring and newly replaced spring is used to verify the results. For finding detailed stress distribution, finite element analysis is used to find stresses and deflection in both the helical springs. Finite element analysis is a method which is used to find proximate solutions of a physical problem defined in a finite domain. In this research work, modeling of spring is accomplished using Solid Works and analysis on Ansys.

Colloidal suspensions in external rotating electric field: experimental studies and prospective applications in physics, material science, and biomedicine

Science.gov (United States)

Yakovlev, Egor V.; Troshina, Anna V.; Korsakova, Sofia A.; Andronik, Mikhail; Rodionov, Ilya A.; Aliev, Ismail N.; Zaytsev, Kirill I.; Cherkasova, Olga P.; Tuchin, Valery V.; Yurchenko, Stanislav O.

2018-04-01

Colloidal suspensions and tunable self-assembly of colloidal particles attract a great interest in recent years. In this paper, we propose a new setup and technology for studies of self-assembly of colloidal particles, interection of which between themselves is tuned by external rotating electric fields. We reveal wide prospectives of electric field employment for tunable self-assembly, from suspensions of inorganic particles to ensembles of biological cells. These results make enable particle-resolved studies of various collective phenomena and fundamental processes in many-particle systems in equilibrium state and far from it, while the dynamics can be resolved at the level of individual particles using video microscopy. For the first time, we demonstrate that, apart from ability to prepare photonic crystalline films of inorganic silica particles, the tunable self-assembly provides a novel technological way for manipulation with ensembles of biological cells by control of interactions between them.

Equilibrium and out-of-equilibrium thermodynamics in supercooled liquids and glasses

International Nuclear Information System (INIS)

Mossa, S; Nave, E La; Tartaglia, P; Sciortino, F

2003-01-01

We review the inherent structure thermodynamical formalism and the formulation of an equation of state (EOS) for liquids in equilibrium based on the (volume) derivatives of the statistical properties of the potential energy surface. We also show that, under the hypothesis that during ageing the system explores states associated with equilibrium configurations, it is possible to generalize the proposed EOS to out-of-equilibrium (OOE) conditions. The proposed formulation is based on the introduction of one additional parameter which, in the chosen thermodynamic formalism, can be chosen as the local minimum where the slowly relaxing OOE liquid is trapped

Some Considerations on the Fundamentals of Chemical Kinetics: Steady State, Quasi-Equilibrium, and Transition State Theory

Science.gov (United States)

Perez-Benito, Joaquin F.

2017-01-01

The elementary reaction sequence A ? I ? Products is the simplest mechanism for which the steady-state and quasi-equilibrium kinetic approximations can be applied. The exact integrated solutions for this chemical system allow inferring the conditions that must fulfill the rate constants for the different approximations to hold. A graphical…

Non-equilibrium steady state of a driven levitated particle with feedback cooling

International Nuclear Information System (INIS)

Gieseler, Jan; Novotny, Lukas; Moritz, Clemens; Dellago, Christoph

2015-01-01

Laser trapped nanoparticles have been recently used as model systems to study fundamental relations holding far from equilibrium. Here we study a nanoscale silica sphere levitated by a laser in a low density gas. The center of mass motion of the particle is subjected, at the same time, to feedback cooling and a parametric modulation driving the system into a non-equilibrium steady state. Based on the Langevin equation of motion of the particle, we derive an analytical expression for the energy distribution of this steady state showing that the average and variance of the energy distribution can be controlled separately by appropriate choice of the friction, cooling and modulation parameters. Energy distributions determined in computer simulations and measured in a laboratory experiment agree well with the analytical predictions. We analyze the particle motion also in terms of the quadratures and find thermal squeezing depending on the degree of detuning. (paper)

Chemical equilibrium of hydrogen and aqueous solutions of 1:1 bicarbonate and formate salts with a common cation.

NARCIS (Netherlands)

Engel, D.C.; Engel, D.C.; Versteeg, Geert; van Swaaij, Willibrordus Petrus Maria

1997-01-01

This was accomplished for the sodium (M = Na), potassium (M = K) and ammonium (M = NH4) systems by measuring the equilibrium composition. This reaction was allowed to proceed from both sides of the equilibrium in a suspension of Pd/C and Pd/γ-Al2O3 catalyst particles, and was carried out at 20, 40

Influence of crystal habit on trimethoprim suspension formulation.

Science.gov (United States)

Tiwary, A K; Panpalia, G M

1999-02-01

The role of crystal habit in influencing the physical stability and pharmacokinetics of trimethoprim suspensions was examined. Different habits for trimethoprim (TMP) were obtained by recrystallizing the commercial sample (PD) utilizing solvent-change precipitation method. Four distinct habits (microscopic observation) belonging to the same polymorphic state (DSC studies) were selected for studies. Preformulation and formulation studies were carried out on suspension dosage forms containing these crystals. The freshly prepared suspensions were also evaluated for their pharmacokinetic behaviour on healthy human volunteers using a cross over study. Variation of crystallization conditions produces different habits of TMP. Among the different crystal habits exhibiting same polymorphic state, the most anisometric crystal showed best physical stability in terms of sedimentation volume and redispersibility. However, habit did not significantly affect the extent of TMP excreted in urine. Modification of surface morphology without significantly altering the polymorphic state can be utilized for improving physical stability of TMP suspensions. However, the pharmacokinetic profile remains unaltered.

Saturated ideal kink/peeling formations described as three-dimensional magnetohydrodynamic tokamak equilibrium states

Energy Technology Data Exchange (ETDEWEB)

Cooper, W. A.; Brunetti, D.; Duval, B. P.; Faustin, J. M.; Graves, J. P.; Kleiner, A.; Patten, H.; Pfefferlé, D.; Porte, L.; Raghunathan, M.; Reimerdes, H.; Sauter, O.; Tran, T. M., E-mail: wilfred.cooper@epfl.ch [Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne (Switzerland)

2016-04-15

Free boundary magnetohydrodynamic equilibrium states with spontaneous three dimensional deformations of the plasma-vacuum interface are computed for the first time. The structures obtained have the appearance of saturated ideal external kink/peeling modes. High edge pressure gradients yield toroidal mode number n = 1 corrugations for a high edge bootstrap current and larger n distortions when this current is small. Deformations in the plasma boundary region induce a nonaxisymmetric Pfirsch-Schlüter current driving a field-aligned current ribbon consistent with reported experimental observations. A variation in the 3D equilibrium confirms that the n = 1 mode is a kink/peeling structure. We surmise that our calculated equilibrium structures constitute a viable model for the edge harmonic oscillations and outer modes associated with a quiescent H-mode operation in shaped tokamak plasmas.

Chemical equilibrium model for high- Tc and heavy fermion superconductors: the density of states

International Nuclear Information System (INIS)

Kallio, A.; Hissa, J.; Hayrynen, T.; Braysy, V.; Sakkinen, T.

1998-01-01

The chemical equilibrium model is based on the idea of correlated electron pairs, which in singlet state can exist as quasimolecules in the superfluid and normal states of a superconductor. These preformed pairs are bosons which can undergo a Bose-Einstein condensation in analogy with the superfluidity of 4 He+ 3 He-mixture. The bosons (B ++ ) and the fermions (h + ) are in chemical equilibrium with respect to the reaction B ++ ↔ 2h + , at any temperature. The mean densities of bosons and fermions (quasiholes) n B (T) and n h (T) are determined from the thermodynamics of the equilibrium reaction in terms of a single function f(T). By thermodynamics the function f(T) is connected to equilibrium constant φ(T) by 1-f(T) = [1 + φ(T)] -1/2 . Using a simple power law, known to be valid near T = 0, for the chemical constant φ(T) α/t 2γ , t = T/T*, the mean density of quasiholes is given in closed form. This enables one to calculate the corresponding density of states (DOS) D(E) N s /N(0), by solving an integral equation. The NIS- tunneling conductivity near T = 0, given by D(E) compares well with the most recent experiments: D(E) ∼ E γ , for small E and a finite maximum of right size, corresponding to 'finite quasiparticle lifetime'. The corresponding SIS-tunneling conductivity is obtained from a simple convolution and is also in agreement with recent break junction experiments of Hancotte et al. The position of the maximum can be used to obtain the scaling temperature T*, which comes close to the one measured by Hall coefficient in the normal state. A simple explanation for the spingap effect in NMR is given. (Copyright (1998) World Scientific Publishing Co. Pte. Ltd)

Para-equilibrium phase diagrams

International Nuclear Information System (INIS)

Pelton, Arthur D.; Koukkari, Pertti; Pajarre, Risto; Eriksson, Gunnar

2014-01-01

Highlights: • A rapidly cooled system may attain a state of para-equilibrium. • In this state rapidly diffusing elements reach equilibrium but others are immobile. • Application of the Phase Rule to para-equilibrium phase diagrams is discussed. • A general algorithm to calculate para-equilibrium phase diagrams is described. - Abstract: If an initially homogeneous system at high temperature is rapidly cooled, a temporary para-equilibrium state may result in which rapidly diffusing elements have reached equilibrium but more slowly diffusing elements have remained essentially immobile. The best known example occurs when homogeneous austenite is quenched. A para-equilibrium phase assemblage may be calculated thermodynamically by Gibbs free energy minimization under the constraint that the ratios of the slowly diffusing elements are the same in all phases. Several examples of calculated para-equilibrium phase diagram sections are presented and the application of the Phase Rule is discussed. Although the rules governing the geometry of these diagrams may appear at first to be somewhat different from those for full equilibrium phase diagrams, it is shown that in fact they obey exactly the same rules with the following provision. Since the molar ratios of non-diffusing elements are the same in all phases at para-equilibrium, these ratios act, as far as the geometry of the diagram is concerned, like “potential” variables (such as T, pressure or chemical potentials) rather than like “normal” composition variables which need not be the same in all phases. A general algorithm to calculate para-equilibrium phase diagrams is presented. In the limit, if a para-equilibrium calculation is performed under the constraint that no elements diffuse, then the resultant phase diagram shows the single phase with the minimum Gibbs free energy at any point on the diagram; such calculations are of interest in physical vapor deposition when deposition is so rapid that phase

Accelerating Multiagent Reinforcement Learning by Equilibrium Transfer.

Science.gov (United States)

Hu, Yujing; Gao, Yang; An, Bo

2015-07-01

An important approach in multiagent reinforcement learning (MARL) is equilibrium-based MARL, which adopts equilibrium solution concepts in game theory and requires agents to play equilibrium strategies at each state. However, most existing equilibrium-based MARL algorithms cannot scale due to a large number of computationally expensive equilibrium computations (e.g., computing Nash equilibria is PPAD-hard) during learning. For the first time, this paper finds that during the learning process of equilibrium-based MARL, the one-shot games corresponding to each state's successive visits often have the same or similar equilibria (for some states more than 90% of games corresponding to successive visits have similar equilibria). Inspired by this observation, this paper proposes to use equilibrium transfer to accelerate equilibrium-based MARL. The key idea of equilibrium transfer is to reuse previously computed equilibria when each agent has a small incentive to deviate. By introducing transfer loss and transfer condition, a novel framework called equilibrium transfer-based MARL is proposed. We prove that although equilibrium transfer brings transfer loss, equilibrium-based MARL algorithms can still converge to an equilibrium policy under certain assumptions. Experimental results in widely used benchmarks (e.g., grid world game, soccer game, and wall game) show that the proposed framework: 1) not only significantly accelerates equilibrium-based MARL (up to 96.7% reduction in learning time), but also achieves higher average rewards than algorithms without equilibrium transfer and 2) scales significantly better than algorithms without equilibrium transfer when the state/action space grows and the number of agents increases.

Oppositely charged colloids out of equilibrium

Science.gov (United States)

Vissers, T.

2010-11-01

Colloids are particles with a size in the range of a few nanometers up to several micrometers. Similar to atomic and molecular systems, they can form gases, liquids, solids, gels and glasses. Colloids can be used as model systems because, unlike molecules, they are sufficiently large to be studied directly with light microscopy and move sufficiently slow to study their dynamics. In this thesis, we study binary systems of polymethylmethacrylate (PMMA) colloidal particles suspended in low-polar solvent mixtures. Since the ions can still partially dissociate, a surface charge builds up which causes electrostatic interactions between the colloids. By carefully tuning the conditions inside the suspension, we make two kinds of particles oppositely charged. To study our samples, we use Confocal Laser Scanning Microscopy (CLSM). The positively and negatively charged particles can be distinguished by a different fluorescent dye. Colloids constantly experience a random motion resulting from random kicks of surrounding solvent molecules. When the attractions between the oppositely charged particles are weak, the particles can attach and detach many times and explore a lot of possible configurations and the system can reach thermodynamic equilibrium. For example, colloidal ‘ionic’ crystals consisting of thousands to millions of particles can form under the right conditions. When the attractions are strong, the system can become kinetically trapped inside a gel-like state. We observe that when the interactions change again, crystals can even emerge again from this gel-like phase. By using local order parameters, we quantitatively study the crystallization of colloidal particles and identify growth defects inside the crystals. We also study the effect of gravity on the growth of ionic crystals by using a rotating stage. We find that sedimentation can completely inhibit crystal growth and plays an important role in crystallization from the gel-like state. The surface

Local Nash equilibrium in social networks.

Science.gov (United States)

Zhang, Yichao; Aziz-Alaoui, M A; Bertelle, Cyrille; Guan, Jihong

2014-08-29

Nash equilibrium is widely present in various social disputes. As of now, in structured static populations, such as social networks, regular, and random graphs, the discussions on Nash equilibrium are quite limited. In a relatively stable static gaming network, a rational individual has to comprehensively consider all his/her opponents' strategies before they adopt a unified strategy. In this scenario, a new strategy equilibrium emerges in the system. We define this equilibrium as a local Nash equilibrium. In this paper, we present an explicit definition of the local Nash equilibrium for the two-strategy games in structured populations. Based on the definition, we investigate the condition that a system reaches the evolutionary stable state when the individuals play the Prisoner's dilemma and snow-drift game. The local Nash equilibrium provides a way to judge whether a gaming structured population reaches the evolutionary stable state on one hand. On the other hand, it can be used to predict whether cooperators can survive in a system long before the system reaches its evolutionary stable state for the Prisoner's dilemma game. Our work therefore provides a theoretical framework for understanding the evolutionary stable state in the gaming populations with static structures.

From Wang-Chen System with Only One Stable Equilibrium to a New Chaotic System Without Equilibrium

Science.gov (United States)

Pham, Viet-Thanh; Wang, Xiong; Jafari, Sajad; Volos, Christos; Kapitaniak, Tomasz

2017-06-01

Wang-Chen system with only one stable equilibrium as well as the coexistence of hidden attractors has attracted increasing interest due to its striking features. In this work, the effect of state feedback on Wang-Chen system is investigated by introducing a further state variable. It is worth noting that a new chaotic system without equilibrium is obtained. We believe that the system is an interesting example to illustrate the conversion of hidden attractors with one stable equilibrium to hidden attractors without equilibrium.

19 CFR 210.23 - Suspension of investigation.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Suspension of investigation. 210.23 Section 210.23 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Motions § 210.23 Suspension of investigation. Any party may move to...

How should we understand non-equilibrium many-body steady states?

Science.gov (United States)

Maghrebi, Mohammad; Gorshkov, Alexey

: Many-body systems with both coherent dynamics and dissipation constitute a rich class of models which are nevertheless much less explored than their dissipationless counterparts. The advent of numerous experimental platforms that simulate such dynamics poses an immediate challenge to systematically understand and classify these models. In particular, nontrivial many-body states emerge as steady states under non-equilibrium dynamics. In this talk, I use a field-theoretic approach based on the Keldysh formalism to study nonequilibrium phases and phase transitions in such models. I show that an effective temperature generically emerges as a result of dissipation, and the universal behavior including the dynamics near the steady state is described by a thermodynamic universality class. In the end, I will also discuss possibilities that go beyond the paradigm of an effective thermodynamic behavior.

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.)

Evaluating damping elements for two-stage suspension vehicles

Directory of Open Access Journals (Sweden)

Ronald M. Martinod R.

2012-01-01

Full Text Available The technical state of the damping elements for a vehicle having two-stage suspension was evaluated by using numerical models based on the multi-body system theory; a set of virtual tests used the eigenproblem mathematical method. A test was developed based on experimental modal analysis (EMA applied to a physical system as the basis for validating the numerical models. The study focused on evaluating vehicle dynamics to determine the influence of the dampers’ technical state in each suspension state.

Suspension Trauma / Orthostatic Intolerance

Science.gov (United States)

... Suspension Trauma/Orthostatic Intolerance Safety and Health Information Bulletin SHIB 03-24-2004, updated 2011 This Safety ... the harness, the environmental conditions, and the worker's psychological state all may increase the onset and severity ...

Controlling Non-Equilibrium Structure Formation on the Nanoscale.

Science.gov (United States)

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.

Vapour-liquid equilibrium properties for two- and three-dimensional Lennard-Jones fluids from equations of state

International Nuclear Information System (INIS)

Mulero, A.; Cuadros, F; Faundez, C.A.

1999-01-01

Vapour-liquid equilibrium properties for both three- and two-dimensional Lennard-Jones fluids were obtained using simple cubic-in-density equations of state proposed by the authors. Results were compared with those obtained by other workers from computer simulations and also with results given by other more complex semi-theoretical or semi-empirical equations of state. In the three-dimensional case good agreement is found for all properties and all temperatures. In the two-dimensional case only the coexistence densities were compared, producing good agreement for low temperatures only. The present work is the first to give numerical data for the vapour-liquid equilibrium properties of Lennard-Jones fluids calculated from equations of state. Copyright (1999) CSIRO Australia

Equilibrium models and variational inequalities

CERN Document Server

Konnov, Igor

2007-01-01

The concept of equilibrium plays a central role in various applied sciences, such as physics (especially, mechanics), economics, engineering, transportation, sociology, chemistry, biology and other fields. If one can formulate the equilibrium problem in the form of a mathematical model, solutions of the corresponding problem can be used for forecasting the future behavior of very complex systems and, also, for correcting the the current state of the system under control. This book presents a unifying look on different equilibrium concepts in economics, including several models from related sciences.- Presents a unifying look on different equilibrium concepts and also the present state of investigations in this field- Describes static and dynamic input-output models, Walras, Cassel-Wald, spatial price, auction market, oligopolistic equilibrium models, transportation and migration equilibrium models- Covers the basics of theory and solution methods both for the complementarity and variational inequality probl...

Vapor-liquid equilibrium prediction with pseudo-cubic equation of state for binary mixtures containing hydrogen, helium, or neon

Energy Technology Data Exchange (ETDEWEB)

Kato, M.; Tanaka, H. (Nihon Univ.,Fukushima, (Japan). Faculty of Enineering)

1990-03-01

As an equation of state of vapor-liquid equilibrium, an original pseudo-cubic equation of state was previously proposed by the authors of this report and its study is continued. In the present study, new effective critical values of hydrogen, helium and neon were determined empirically from vapor-liquid equilibrium data of literature values against their critical temperatures, critical pressures and critical volumes. The vapor-liquid equilibrium relations of binary system quantum gas mixtures were predicted combining the conventinal pseudo-cubic equation of state and the new effective critical values, and without using binary heteromolecular interaction parameter. The predicted values of hydrogen-ethylene, helium-propane and neon-oxygen systems were compared with literature values. As a result, it was indicated that the vapor-liquid relations of binary system mixtures containing hydrogen, helium and neon can be predicted with favorable accuracy combining the effective critical values and the three parameter pseudo-cubic equation of state. 37 refs., 3 figs., 4 tabs.

Magnetic Suspension Technology Workshop

International Nuclear Information System (INIS)

Keckler, C.R.; Groom, N.J.; Britcher, C.P.

1993-01-01

In order to identify the state of magnetic suspension technology in such areas as rotating systems, pointing of experiments or subsystems, payload isolation, and superconducting materials, a workshop on Magnetic Suspension Technology was held at the Langley Research Center in Hampton, Virginia, on 2-4 Feb. 1988. The workshop included five technical sessions in which a total of 24 papers were presented. The technical sessions covered the areas of pointing, isolation, and measurement, rotating systems, modeling and control, and superconductors. A list of attendees is provided. Separate abstracts have been prepared for articles from this report

Mathematical models and equilibrium in irreversible microeconomics

Directory of Open Access Journals (Sweden)

Anatoly M. Tsirlin

2010-07-01

Full Text Available A set of equilibrium states in a system consisting of economic agents, economic reservoirs, and firms is considered. Methods of irreversible microeconomics are used. We show that direct sale/purchase leads to an equilibrium state which depends upon the coefficients of supply/demand functions. To reach the unique equilibrium state it is necessary to add either monetary exchange or an intermediate firm.

DIAGNOSIS OF FINANCIAL EQUILIBRIUM

Directory of Open Access Journals (Sweden)

SUCIU GHEORGHE

2013-04-01

Full Text Available The analysis based on the balance sheet tries to identify the state of equilibrium (disequilibrium that exists in a company. The easiest way to determine the state of equilibrium is by looking at the balance sheet and at the information it offers. Because in the balance sheet there are elements that do not reflect their real value, the one established on the market, they must be readjusted, and those elements which are not related to the ordinary operating activities must be eliminated. The diagnosis of financial equilibrium takes into account 2 components: financing sources (ownership equity, loaned, temporarily attracted. An efficient financial equilibrium must respect 2 fundamental requirements: permanent sources represented by ownership equity and loans for more than 1 year should finance permanent needs, and temporary resources should finance the operating cycle.

Radiation resistivity of frozen insulin solutions and suspensions

Energy Technology Data Exchange (ETDEWEB)

Soboleva, N N; Ivanova, A I; Talrose, V L; Trofimov, V I; Fedotov, V P [AN SSSR, Moscow. Inst. Fizicheskoj Khimii; Research Institute for Biological Testing of Chemicals, Moscow (USSR); Institute of Experimental Endocrinology and Hormon Chemistry, Moscow (USSR))

1981-10-01

The effect of great increase in radiation resistance of insulin solutions and suspensions after irradiation at low temperatures in the frozen state was observed by absorption spectrophotometry, paper chromatography and biological analysis. The data obtained suggest irradiation of frozen insulin solutions and suspensions as a method for its sterilization.

A corrected NEGF + DFT approach for calculating electronic transport through molecular devices: Filling bound states and patching the non-equilibrium integration

International Nuclear Information System (INIS)

Li Rui; Zhang Jiaxing; Hou Shimin; Qian Zekan; Shen Ziyong; Zhao Xingyu; Xue Zengquan

2007-01-01

We discuss two problems in the conventional approach for studying charge transport in molecular electronic devices that is based on the non-equilibrium Green's function formalism and density functional theory, i.e., the bound states and the numerical integration of the non-equilibrium density matrix. A scheme of filling the bound states in the bias window and a method of patching the non-equilibrium integration are proposed, both of which are referred to as the non-equilibrium correction. The discussion is illustrated by means of calculations on a model system consisting of a 4,4 bipyridine molecule connected to two semi-infinite gold monatomic chains

Boundary state in an integrable quantum field theory out of equilibrium

International Nuclear Information System (INIS)

Sotiriadis, Spyros; Takacs, Gabor; Mussardo, Giuseppe

2014-01-01

We study a quantum quench of the mass and the interaction in the Sinh-Gordon model starting from a large initial mass and zero initial coupling. Our focus is on the determination of the expansion of the initial state in terms of post-quench excitations. We argue that the large energy profile of the involved excitations can be relevant for the late time behaviour of the system and common regularization schemes are unreliable. We therefore proceed in determining the initial state by first principles expanding it in a systematic and controllable fashion on the basis of the asymptotic states. Our results show that, for the special limit of pre-quench parameters we consider, it assumes a squeezed state form that has been shown to evolve so as to exhibit the equilibrium behaviour predicted by the Generalized Gibbs Ensemble

Boundary state in an integrable quantum field theory out of equilibrium

Energy Technology Data Exchange (ETDEWEB)

Sotiriadis, Spyros [Department of Physics, University of Pisa (Italy); INFN, Pisa section (Italy); Takacs, Gabor [Department of Theoretical Physics, Budapest University of Technology and Economics (Hungary); MTA-BME “Momentum” Statistical Field Theory Research Group (Hungary); Mussardo, Giuseppe [SISSA and INFN, Trieste (Italy); The Abdus Salam ICTP, Trieste (Italy)

2014-06-27

We study a quantum quench of the mass and the interaction in the Sinh-Gordon model starting from a large initial mass and zero initial coupling. Our focus is on the determination of the expansion of the initial state in terms of post-quench excitations. We argue that the large energy profile of the involved excitations can be relevant for the late time behaviour of the system and common regularization schemes are unreliable. We therefore proceed in determining the initial state by first principles expanding it in a systematic and controllable fashion on the basis of the asymptotic states. Our results show that, for the special limit of pre-quench parameters we consider, it assumes a squeezed state form that has been shown to evolve so as to exhibit the equilibrium behaviour predicted by the Generalized Gibbs Ensemble.

Fumed and Precipitated Hydrophilic Silica Suspension Gels in Mineral Oil: Stability and Rheological Properties

Directory of Open Access Journals (Sweden)

Yoshiki Sugino

2017-08-01

Full Text Available Hydrophilic fumed silica (FS and precipitated silica (PS powders were suspended in mineral oil; increasing the silica volume fraction (φ in the suspension led to the formation of sol, pre-gel, and gel states. Gelation took place at lower φ values in the FS than the PS suspension because of the lower silanol density on the FS surface. The shear stresses and dynamic moduli of the FS and PS suspensions were measured as a function of φ. Plots of the apparent shear viscosity against shear rate depended on φ and the silica powder. The FS suspensions in the gel state exhibited shear thinning, followed by a weak shear thickening or by constant viscosity with an increasing shear rate. In contrast, the PS suspensions in the gel state showed shear thinning, irrespective of φ. The dynamic moduli of the pre-gel and gel states were dependent on the surface silanol density: at a fixed φ, the storage modulus G′ in the linear viscoelasticity region was larger for the FS than for the PS suspension. Beyond the linear region, the G′ of the PS suspensions showed strain hardening and the loss modulus G″ of the FS and PS suspensions exhibited weak strain overshoot.

The Evolution of Discipline: Alternative to Suspension Programs.

Science.gov (United States)

Streva, Michael A.

Historically, the chosen method of discipline in United States schools has gone from corporal punishment to an emphasis on suspension. Recently, as principals have become less certain about the extent of their authority to suspend students, many inschool programs have been developed as alternatives to suspension. Among the advantages of such…

Glass transition and aging in dense suspensions of thermosensitive microgel particles

NARCIS (Netherlands)

Purnomo, E.H; van den Ende, Henricus T.M.; Vanapalli Veera, V.S.A.R.; Vanapalli, Srinivas; Mugele, Friedrich Gunther

2008-01-01

We report a thermosensitive microgel suspension that can be tuned reversibly between the glass state at low temperature and the liquid state at high temperature. Unlike hard spheres, we find that the glass transition for these suspensions is governed by both the volume fraction and the softness of

Optimal Vibration Control for Tracked Vehicle Suspension Systems

Directory of Open Access Journals (Sweden)

Yan-Jun Liang

2013-01-01

Full Text Available Technique of optimal vibration control with exponential decay rate and simulation for vehicle active suspension systems is developed. Mechanical model and dynamic system for a class of tracked vehicle suspension vibration control is established and the corresponding system of state space form is described. In order to prolong the working life of suspension system and improve ride comfort, based on the active suspension vibration control devices and using optimal control approach, an optimal vibration controller with exponential decay rate is designed. Numerical simulations are carried out, and the control effects of the ordinary optimal controller and the proposed controller are compared. Numerical simulation results illustrate the effectiveness of the proposed technique.

Shear-induced particle migration in suspensions of rods

Energy Technology Data Exchange (ETDEWEB)

Mondy, L.A. (Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)); Brenner, H. (Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)); Altobelli, S.A. (The Lovelace Institutes, 2425 Ridgecrest Drive, S. E., Albuquerque, New Mexico 87108 (United States)); Abbott, J.R.; Graham, A.L. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

1994-03-01

Shear-induced migration of particles occurs in suspensions of neutrally buoyant spheres in Newtonian fluids undergoing shear in the annular space between two rotating, coaxial cylinders (a wide-gap Couette), even when the suspension is in creeping flow. Previous studies have shown that the rate of migration of spherical particles from the high-shear-rate region near the inner (rotating) cylinder to the low-shear-rate region near the outer (stationary) cylinder increases rapidly with increasing sphere size. To determine the effect of particle shape, the migration of rods suspended in Newtonian fluids was recently measured. The behavior of several suspensions was studied. Each suspension contained well-characterized, uniform rods with aspect ratios ranging from 2 to 18 at either 0.30 or 0.40 volume fraction. At the same volume fraction of solids, the steady-state, radial concentration profiles for rods were independent of aspect ratio and were indistinguishable from those obtained from suspended spheres. Only minor differences near the walls (attributable to the finite size of the rods relative to the curvature of the walls) appeared to differentiate the profiles. Data taken during the transition from a well-mixed suspension to the final steady state show that the rate of migration increased as the volume of the individual rods increased.

Near equilibrium dynamics and one-dimensional spatial—temporal structures of polar active liquid crystals

International Nuclear Information System (INIS)

Yang Xiao-Gang; Wang Qi; Forest, M. Gregory

2014-01-01

We systematically explore near equilibrium, flow-driven, and flow-activity coupled dynamics of polar active liquid crystals using a continuum model. Firstly, we re-derive the hydrodynamic model to ensure the thermodynamic laws are obeyed and elastic stresses and forces are consistently accounted. We then carry out a linear stability analysis about constant steady states to study near equilibrium dynamics around the steady states, revealing long-wave instability inherent in this model system and how active parameters in the model affect the instability. We then study model predictions for one-dimensional (1D) spatial—temporal structures of active liquid crystals in a channel subject to physical boundary conditions. We discuss the model prediction in two selected regimes, one is the viscous stress dominated regime, also known as the flow-driven regime, while the other is the full regime, in which all active mechanisms are included. In the viscous stress dominated regime, the polarity vector is driven by the prescribed flow field. Dynamics depend sensitively on the physical boundary condition and the type of the driven flow field. Bulk-dominated temporal periodic states and spatially homogeneous states are possible under weak anchoring conditions while spatially inhomogeneous states exist under strong anchoring conditions. In the full model, flow-orientation interaction generates a host of planar as well as out-of-plane spatial—temporal structures related to the spontaneous flows due to the molecular self-propelled motion. These results provide contact with the recent literature on active nematic suspensions. In addition, symmetry breaking patterns emerge as the additional active viscous stress due to the polarity vector is included in the force balance. The inertia effect is found to limit the long-time survival of spatial structures to those with small wave numbers, i.e., an asymptotic coarsening to long wave structures. A rich set of mechanisms for generating

39 CFR 320.7 - Suspension for advertisements accompanying parcels or periodicals.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Suspension for advertisements accompanying parcels or periodicals. 320.7 Section 320.7 Postal Service UNITED STATES POSTAL SERVICE RESTRICTIONS ON PRIVATE CARRIAGE OF LETTERS SUSPENSION OF THE PRIVATE EXPRESS STATUTES § 320.7 Suspension for advertisements accompanying parcels or periodicals. (a) Th...

Spontaneity and Equilibrium: Why "?G Equilibrium" Are Incorrect

Science.gov (United States)

Raff, Lionel M.

2014-01-01

The fundamental criteria for chemical reactions to be spontaneous in a given direction are generally incorrectly stated as ?G equilibrium are also misstated as being ?G = 0 or ?A = 0. Following a brief review of the…

Quantum dynamical semigroups and approach to equilibrium

International Nuclear Information System (INIS)

Frigerio, A.

1977-01-01

For a quantum dynamical semigroup possessing a faithful normal stationary state, some conditions are discussed, which ensure the uniqueness of the equilibrium state and/or the approach to equilibrium for arbitrary initial condition. (Auth.)

Far-from-Equilibrium Route to Superthermal Light in Bimodal Nanolasers

Directory of Open Access Journals (Sweden)

Mathias Marconi

2018-01-01

Full Text Available Microscale and nanoscale lasers inherently exhibit rich photon statistics due to complex light-matter interaction in a strong spontaneous emission noise background. It is well known that they may display superthermal fluctuations—photon superbunching—in specific situations due to either gain competition, leading to mode-switching instabilities, or carrier-carrier coupling in superradiant microcavities. Here we show a generic route to superbunching in bimodal nanolasers by preparing the system far from equilibrium through a parameter quench. We demonstrate, both theoretically and experimentally, that transient dynamics after a short-pump-pulse-induced quench leads to heavy-tailed superthermal statistics when projected onto the weak mode. We implement a simple experimental technique to access the probability density functions that further enables quantifying the distance from thermal equilibrium via the thermodynamic entropy. The universality of this mechanism relies on the far-from-equilibrium dynamical scenario, which can be mapped to a fast cooling process of a suspension of Brownian particles in a liquid. Our results open up new avenues to mold photon statistics in multimode optical systems and may constitute a test bed to investigate out-of-equilibrium thermodynamics using micro or nanocavity arrays.

Far-from-Equilibrium Route to Superthermal Light in Bimodal Nanolasers

Science.gov (United States)

Marconi, Mathias; Javaloyes, Julien; Hamel, Philippe; Raineri, Fabrice; Levenson, Ariel; Yacomotti, Alejandro M.

2018-02-01

Microscale and nanoscale lasers inherently exhibit rich photon statistics due to complex light-matter interaction in a strong spontaneous emission noise background. It is well known that they may display superthermal fluctuations—photon superbunching—in specific situations due to either gain competition, leading to mode-switching instabilities, or carrier-carrier coupling in superradiant microcavities. Here we show a generic route to superbunching in bimodal nanolasers by preparing the system far from equilibrium through a parameter quench. We demonstrate, both theoretically and experimentally, that transient dynamics after a short-pump-pulse-induced quench leads to heavy-tailed superthermal statistics when projected onto the weak mode. We implement a simple experimental technique to access the probability density functions that further enables quantifying the distance from thermal equilibrium via the thermodynamic entropy. The universality of this mechanism relies on the far-from-equilibrium dynamical scenario, which can be mapped to a fast cooling process of a suspension of Brownian particles in a liquid. Our results open up new avenues to mold photon statistics in multimode optical systems and may constitute a test bed to investigate out-of-equilibrium thermodynamics using micro or nanocavity arrays.

Equilibrium state of colliding electron beams

Directory of Open Access Journals (Sweden)

R. L. Warnock

2003-10-01

Full Text Available We study a nonlinear integral equation that is a necessary condition on the equilibrium phase-space distribution function of stored, colliding electron beams. It is analogous to the Haïssinski equation, being derived from Vlasov-Fokker-Planck theory, but is quite different in form. The equation is analyzed for the case of the Chao-Ruth model of the beam-beam interaction in 1 degree of freedom, a so-called strong-strong model with nonlinear beam-beam force. We prove the existence of a unique solution, for sufficiently small beam current, by an application of the implicit function theorem. We have not yet proved that this solution is positive, as would be required to establish existence of an equilibrium. There is, however, numerical evidence of a positive solution. We expect that our analysis can be extended to more realistic models.

An Experimental Study of the Equation of State of Nano Colloids Using a Novel Dielectrophoresis Osmometer

Science.gov (United States)

Shen, Chong; Sirorattanakul, Krittanon; Huang, Hao; Ou-Yang, H. Daniel

This talk reports a novel method to measure equation of state (EOS) relating the colloidal osmotic pressure with particle concentration. Recent theories and simulations have made predictions for such EOS for various particle interactions, but measurements are rare. Conventional methods to determine the osmotic pressure in colloid suspensions use gravity or centrifugation. However, the nano colloidal system requires a long time to reach equilibrium when the particle sizes are small or their mass densities are close to that of the solvent. Here, we propose a new method involving electric bottle that will solve all such challenges. In the equilibrium under dielectrophoresis (DEP) force field, the spatial distribution of the particle density can be determined from fluorescent microscopy. According to Einstein's osmotic equilibrium theory, the osmotic pressure of the colloid suspensions can be calculated. Then, the DEP force field is calibrated using the well-established EOS of colloidal hard spheres. Using the known force field, we determine the EOS for other particles with various interactions and compare the results with theoretical predictions. This work supports by NSF-DMR 0923299, Lehigh department of physics, Emulsion Polymers Institute.

The Non-Equilibrium Statistical Distribution Function for Electrons and Holes in Semiconductor Heterostructures in Steady-State Conditions

Directory of Open Access Journals (Sweden)

Krzysztof Jόzwikowska

2015-06-01

Full Text Available The main goal of this work is to determine a statistical non-equilibrium distribution function for the electron and holes in semiconductor heterostructures in steady-state conditions. Based on the postulates of local equilibrium, as well as on the integral form of the weighted Gyarmati’s variational principle in the force representation, using an alternative method, we have derived general expressions, which have the form of the Fermi–Dirac distribution function with four additional components. The physical interpretation of these components has been carried out in this paper. Some numerical results of a non-equilibrium distribution function for an electron in HgCdTe structures are also presented.

Crust formation in drying colloidal suspensions

KAUST Repository

Style, R. W.

2010-06-30

During the drying of colloidal suspensions, the desiccation process causes the suspension near the air interface to consolidate into a connected porous matrix or crust. Fluid transport in the porous medium is governed by Darcy\\'s law and the equations of poroelasticity, while the equations of colloid physics govern processes in the suspension. We derive new equations describing this process, including unique boundary conditions coupling the two regions, yielding a moving-boundary model of the concentration and stress profiles during drying. A solution is found for the steady-state growth of a nedimensional crust during constant evaporation rate from the surface. The solution is used to demonstrate the importance of the system boundary conditions on stress profiles and diffusivity in a drying crust. © 2011 The Royal Society.

Toward a general psychological model of tension and suspense.

Science.gov (United States)

Lehne, Moritz; Koelsch, Stefan

2015-01-01

Tension and suspense are powerful emotional experiences that occur in a wide variety of contexts (e.g., in music, film, literature, and everyday life). The omnipresence of tension and suspense suggests that they build on very basic cognitive and affective mechanisms. However, the psychological underpinnings of tension experiences remain largely unexplained, and tension and suspense are rarely discussed from a general, domain-independent perspective. In this paper, we argue that tension experiences in different contexts (e.g., musical tension or suspense in a movie) build on the same underlying psychological processes. We discuss key components of tension experiences and propose a domain-independent model of tension and suspense. According to this model, tension experiences originate from states of conflict, instability, dissonance, or uncertainty that trigger predictive processes directed at future events of emotional significance. We also discuss possible neural mechanisms underlying tension and suspense. The model provides a theoretical framework that can inform future empirical research on tension phenomena.

Small angle neutron scattering (SANS) under non-equilibrium conditions

International Nuclear Information System (INIS)

Oberthur, R.C.

1984-01-01

The use of small angle neutron scattering (SANS) for the study of systems under non-equilibrium conditions is illustrated by three types of experiments in the field of polymer research: - the relaxation of a system from an initial non-equilibrium state towards equilibrium, - the cyclic or repetitive installation of a series of non-equilibrium states in a system, - the steady non-equilibrium state maintained by a constant dissipation of energy within the system. Characteristic times obtained in these experiments with SANS are compared with the times obtained from quasi-elastic neutron and light scattering, which yield information about the equilibrium dynamics of the system. The limits of SANS applied to non-equilibrium systems for the measurement of relaxation times at different length scales are shown and compared to the limits of quasielastic neutron and light scattering

Design and characterization of an electromagnetic energy harvester for vehicle suspensions

International Nuclear Information System (INIS)

Zuo, Lei; Scully, Brian; Shestani, Jurgen; Zhou, Yu

2010-01-01

During the everyday usage of an automobile, only 10–16% of the fuel energy is used to drive the car—to overcome the resistance from road friction and air drag. One important loss is the dissipation of vibration energy by shock absorbers in the vehicle suspension under the excitation of road irregularity and vehicle acceleration or deceleration. In this paper we design, characterize and test a retrofit regenerative shock absorber which can efficiently recover the vibration energy in a compact space. Rare-earth permanent magnets and high permeable magnetic loops are used to configure a four-phase linear generator with increased efficiency and reduced weight. The finite element method is used to analyze the magnetic field and guide the design optimization. A theoretical model is created to analytically characterize the waveforms and regenerated power of the harvester at various vibration amplitudes, frequencies, equilibrium positions and design parameters. It was found that the waveform and RMS voltage of the individual coils will depend on the equilibrium position but the total energy will not. Experimental studies of a 1:2 scale prototype are conducted and the results agree very well with the theoretical predictions. Such a regenerative shock absorber will be able to harvest 16–64 W power at 0.25–0.5 m s −1 RMS suspension velocity

On the influence of environmental factors on radon levels in caves of Ribeira valley state parks, SP and evaluation of radioactive equilibrium and equilibrium factor between radon and its progeny

International Nuclear Information System (INIS)

Alberigi, Simone

2011-01-01

In the present study it was carried out the monitoring of radon in caves distributed among three state parks of Sao Paulo. The radon concentration were determinate in Morro Preto and Santana caves, located at PETAR - Parque Estadual Turistico do Alto Ribeira (High Ribeira River Tourist State Park), Diabo cave, situated in PEJ - Parque Estadual de Jacupiranga (Jacupiranga State Park) and Colorida cave located in PEI - Parque Estadual Intervales (Intervales State Park PEI). The monitoring covered measurements between April 2009 and June 2010. Radon concentrations were carried out by using the technique of passive detection with CR-39 solid state nuclear track detectors and NRPB diffusion chambers. The detectors were exposed in periods ranging from 30 to 150 days. Radon concentrations varied from 132 Bq/m 3 to 9456 Bq/m 3 . The values of radon concentrations were analyzed together with information about rainfall and internal and external temperature values of the Santana cave environment and regional literature values for a possible relationship between radon variations and weather information. Both the determinations of 22 '6Ra in water samples collected in some caves and rivers and radon emanation from a stalactite collected at Santana cave allowed to verify that the radon in the caves comes from the walls rocks. The verification of the radioactive equilibrium between 222 Rn, 218 Po and '2 14 Po in the exposed detectors was prejudiced by the high tracks densities, committing the methodology effectiveness. The annual effective dose was calculated for three values obtained from the literature for the equilibrium factor. Considering the most realistic scenario, with equilibrium factor of 0.5 and 52 working weeks, the annual effective dose was 5.1 mSv/y. Concerning the worst scenario, which simulates an extreme case, adopting an equilibrium factor equal to 1 and 52 weeks of work per year, the annual effective dose is 10.2 mSv/y. Also with information received from a

Equilibrium and non equilibrium in fragmentation

International Nuclear Information System (INIS)

Dorso, C.O.; Chernomoretz, A.; Lopez, J.A.

2001-01-01

Full text: In this communication we present recent results regarding the interplay of equilibrium and non equilibrium in the process of fragmentation of excited finite Lennard Jones drops. Because the general features of such a potential resemble the ones of the nuclear interaction (fact that is reinforced by the similarity between the EOS of both systems) these studies are not only relevant from a fundamental point of view but also shed light on the problem of nuclear multifragmentation. We focus on the microscopic analysis of the state of the fragmenting system at fragmentation time. We show that the Caloric Curve (i e. the functional relationship between the temperature of the system and the excitation energy) is of the type rise plateau with no vapor branch. The usual rise plateau rise pattern is only recovered when equilibrium is artificially imposed. This result puts a serious question on the validity of the freeze out hypothesis. This feature is independent of the dimensionality or excitation mechanism. Moreover we explore the behavior of magnitudes which can help us determine the degree of the assumed phase transition. It is found that no clear cut criteria is presently available. (Author)

Non-existence of Steady State Equilibrium in the Neoclassical Growth Model with a Longevity Trend

DEFF Research Database (Denmark)

Hermansen, Mikkel Nørlem

of steady state equilibrium when considering the empirically observed trend in longevity. We extend a standard continuous time overlapping generations model by a longevity trend and are thereby able to study the properties of mortality-driven population growth. This turns out to be exceedingly complicated...

37 CFR 11.3 - Suspension of rules.

Science.gov (United States)

2010-07-01

... Section 11.3 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE REPRESENTATION OF OTHERS BEFORE THE UNITED STATES PATENT AND TRADEMARK OFFICE General Provisions General Information § 11.3 Suspension of rules. (a) In an extraordinary situation, when justice requires...

Information-theoretic equilibrium and observable thermalization

Science.gov (United States)

Anzà, F.; Vedral, V.

2017-03-01

A crucial point in statistical mechanics is the definition of the notion of thermal equilibrium, which can be given as the state that maximises the von Neumann entropy, under the validity of some constraints. Arguing that such a notion can never be experimentally probed, in this paper we propose a new notion of thermal equilibrium, focused on observables rather than on the full state of the quantum system. We characterise such notion of thermal equilibrium for an arbitrary observable via the maximisation of its Shannon entropy and we bring to light the thermal properties that it heralds. The relation with Gibbs ensembles is studied and understood. We apply such a notion of equilibrium to a closed quantum system and show that there is always a class of observables which exhibits thermal equilibrium properties and we give a recipe to explicitly construct them. Eventually, an intimate connection with the Eigenstate Thermalisation Hypothesis is brought to light.

Equilibrium state of delta-phase with tellurium in the Sb-Bi-Te system

International Nuclear Information System (INIS)

Gajgukova, V.S.; Dudkin, L.D.; Erofeev, R.S.; Musaelyan, V.V.; Nadzhip, A.Eh.; Sokolov, O.B.

1978-01-01

A research has been carried out with a view to establish the equilibrium state of delta-phase of the composition (Sbsub(1-x)Bisub(x)) 2 Te 3 with tellurium, depending on x and temperature. The Hall effect, the thermoelectromotive force, and the electric conductivity of the samples of Sb-Bi-Te alloys have been measured, the samples being annealed at various temperatures (550 to 250 deg C). The measurement results have shown that as the Bi 2 Te 3 content in the solid solutions increases and temperature decreases, the delta-phase-Te boundary monotonously approaches the stoichiometric composition. Using the research carrid out as the basis, the general character of the equilibrium delta-phase with tellurium boundary has been rendered more precise in Sb-Bi-Te system, depending on the temperature and Bi content (up to 25 at.%)

The concept of equilibrium in organization theory

NARCIS (Netherlands)

Gazendam, H.W.M.

1998-01-01

Many organization theories consist of an interpretation frame and an idea about the ideal equilibrium state. This article explains how the equilibrium concept is used in four organization theories: the theories of Fayol, Mintzberg, Morgan, and Volberda. Equilibrium can be defined as balance, fit or

The concept of equilibrium in organization theory

NARCIS (Netherlands)

Gazendam, Henk W.M.

1997-01-01

Many organization theories consist of an interpretation frame and an idea about the ideal equilibrium state. This article explains how the equilibrium concept is used in four organization theories: the theories of Fayol, Mintzberg, Morgan, and Volberda. Equilibrium can be defined as balance, fit or

Shielding property for thermal equilibrium states in the quantum Ising model

Science.gov (United States)

Móller, N. S.; de Paula, A. L.; Drumond, R. C.

2018-03-01

We show that Gibbs states of nonhomogeneous transverse Ising chains satisfy a shielding property. Namely, whatever the fields on each spin and exchange couplings between neighboring spins are, if the field in one particular site is null, then the reduced states of the subchains to the right and to the left of this site are exactly the Gibbs states of each subchain alone. Therefore, even if there is a strong exchange coupling between the extremal sites of each subchain, the Gibbs states of the each subchain behave as if there is no interaction between them. In general, if a lattice can be divided into two disconnected regions separated by an interface of sites with zero applied field, then we can guarantee a similar result only if the surface contains a single site. Already for an interface with two sites we show an example where the property does not hold. When it holds, however, we show that if a perturbation of the Hamiltonian parameters is done in one side of the lattice, then the other side is completely unchanged, with regard to both its equilibrium state and dynamics.

On Nash Equilibrium and Evolutionarily Stable States That Are Not Characterised by the Folk Theorem.

Directory of Open Access Journals (Sweden)

Jiawei Li

Full Text Available In evolutionary game theory, evolutionarily stable states are characterised by the folk theorem because exact solutions to the replicator equation are difficult to obtain. It is generally assumed that the folk theorem, which is the fundamental theory for non-cooperative games, defines all Nash equilibria in infinitely repeated games. Here, we prove that Nash equilibria that are not characterised by the folk theorem do exist. By adopting specific reactive strategies, a group of players can be better off by coordinating their actions in repeated games. We call it a type-k equilibrium when a group of k players coordinate their actions and they have no incentive to deviate from their strategies simultaneously. The existence and stability of the type-k equilibrium in general games is discussed. This study shows that the sets of Nash equilibria and evolutionarily stable states have greater cardinality than classic game theory has predicted in many repeated games.

On Nash Equilibrium and Evolutionarily Stable States That Are Not Characterised by the Folk Theorem

Science.gov (United States)

Li, Jiawei; Kendall, Graham

2015-01-01

In evolutionary game theory, evolutionarily stable states are characterised by the folk theorem because exact solutions to the replicator equation are difficult to obtain. It is generally assumed that the folk theorem, which is the fundamental theory for non-cooperative games, defines all Nash equilibria in infinitely repeated games. Here, we prove that Nash equilibria that are not characterised by the folk theorem do exist. By adopting specific reactive strategies, a group of players can be better off by coordinating their actions in repeated games. We call it a type-k equilibrium when a group of k players coordinate their actions and they have no incentive to deviate from their strategies simultaneously. The existence and stability of the type-k equilibrium in general games is discussed. This study shows that the sets of Nash equilibria and evolutionarily stable states have greater cardinality than classic game theory has predicted in many repeated games. PMID:26288088

Spontaneity and Equilibrium: Why "?G Equilibrium" Are Incorrect

Science.gov (United States)

Raff, Lionel M.

2014-01-01

The fundamental criteria for chemical reactions to be spontaneous in a given direction are generally incorrectly stated as ?G chemistry textbooks and even in some more advanced texts. Similarly, the criteria for equilibrium are also misstated as being ?G = 0 or ?A = 0. Following a brief review of the…

32 CFR 842.99 - Compromise, termination, and suspension of collection.

Science.gov (United States)

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Compromise, termination, and suspension of collection. 842.99 Section 842.99 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR... States (31 U.S.C. 3701, 3711-3719) § 842.99 Compromise, termination, and suspension of collection. This...

Non-equilibrium phase transitions

CERN Document Server

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.

3 CFR - Suspension of Limitations Under the Jerusalem Embassy Act

Science.gov (United States)

2010-01-01

... 3 The President 1 2010-01-01 2010-01-01 false Suspension of Limitations Under the Jerusalem... June 5, 2009 Suspension of Limitations Under the Jerusalem Embassy Act Memorandum for the Secretary of... States, including section 7(a) of the Jerusalem Embassy Act of 1995 (Public Law 104-45) (the “Act”), I...

Weakly sheared active suspensions: hydrodynamics, stability, and rheology.

Science.gov (United States)

Cui, Zhenlu

2011-03-01

We present a kinetic model for flowing active suspensions and analyze the behavior of a suspension subjected to a weak steady shear. Asymptotic solutions are sought in Deborah number expansions. At the leading order, we explore the steady states and perform their stability analysis. We predict the rheology of active systems including an activity thickening or thinning behavior of the apparent viscosity and a negative apparent viscosity depending on the particle type, flow alignment, and the anchoring conditions, which can be tested on bacterial suspensions. We find remarkable dualities that show that flow-aligning rodlike contractile (extensile) particles are dynamically and rheologically equivalent to flow-aligning discoid extensile (contractile) particles for both tangential and homeotropic anchoring conditions. Another key prediction of this work is the role of the concentration of active suspensions in controlling the rheological behavior: the apparent viscosity may decrease with the increase of the concentration.

Rheology of zirconia suspensions in a nonpolar organic medium

International Nuclear Information System (INIS)

Moloney, V.M.B.; Parris, D.; Edirisinghe, M.J.

1995-01-01

Three dispersants (stearic acid, oleic acid, and poly-(12-hydroxystearic acid)) are compared for their ability to produce low-viscosity suspensions of zirconia in kerosene. Rheological measurements and sediment packing density measurements show that poly(12-hydroxystearic acid) is a better dispersant than stearic acid or oleic acid; this is explained in terms of the longer tail of the poly-(12-hydroxystearic acid) surfactant molecule. The amount of dispersant can be optimized to reduce viscosity and yield point of the suspension, and to eliminate thixotropic hysteresis. The use of a dispersion medium of lower viscosity than the dispersant makes it easy to detect when complete monolayer coverage has been achieved. The loss of pseudoplasticity, brought about by a higher degree of deflocculation, can be recovered by increasing the volume fraction of solids of a suspension and this is beneficial in the plastic forming of ceramics. Rheological measurements showed that these suspensions reach a critical state above a critical shear stress (τ c ). This critical state is described by several parameters, i.e., the Bingham yield stress (τ B ), the plastic viscosity (η PL ), and the critical shear rate (γ c ), which are dependent on the volume fraction of solids

Equilibrium constants in aqueous lanthanide and actinide chemistry from time-resolved fluorescence spectroscopy: The role of ground and excited state reactions

International Nuclear Information System (INIS)

Billard, I.; Luetzenkirchen, K.

2003-01-01

Equilibrium constants for aqueous reactions between lanthanide or actinide ions and (in-) organic ligands contain important information for various radiochemical problems, such as nuclear reprocessing or the migration of radioelements in the geosphere. We study the conditions required to determine equilibrium constants by time-resolved fluorescence spectroscopy measurements. Based on a simulation study it is shown that the possibility to determine equilibrium constants depends upon the reaction rates in the photoexcited states of the lanthanide or actinide ions. (orig.)

Dynamics and non-equilibrium steady state in a system of coupled harmonic oscillators

Energy Technology Data Exchange (ETDEWEB)

Ghesquière, Anne, E-mail: Anne.Ghesquiere@nithep.ac.za; Sinayskiy, Ilya, E-mail: sinayskiy@ukzn.ac.za; Petruccione, Francesco, E-mail: petruccione@ukzn.ac.za

2013-10-15

A system of two coupled oscillators, each of them coupled to an independent reservoir, is analysed. The analytical solution of the non-rotating wave master equation is obtained in the high-temperature and weak coupling limits. No thermal entanglement is found in the high-temperature limit. In the weak coupling limit the system converges to an entangled non-equilibrium steady state. A critical temperature for the appearance of quantum correlations is found.

A study on the criticality search of transuranium recycling BWR core by adjusting supplied fuel composition in equilibrium state

International Nuclear Information System (INIS)

Seino, Takeshi; Sekimoto, Hiroshi

1997-01-01

There have been some difficulties in carrying out an extensive evaluation of the equilibrium state of Light Water Reactor (LWR) recycling operations keeping their fixed criticality condition using conventional design codes, because of the complexity of their calculational model for practical fuel and core design and because of a large amount of calculation time. This study presents an efficient approach to secure the criticality in an equilibrium cycle by adjusting a supplied fuel composition. The criticality search is performed by the use of fuel importance obtained from the equilibrium adjoint to a continuously fuel supplied core burnup equation. Using this method, some numerical analyses were carried out in order to evaluate the mixed oxide (MOX) fuel composition of equilibrium Boiling Water Reactor (BWR) cores satisfying the criticality requirement. The results showed the comprehensive and quantitative characteristics on the equilibrium cores confining transuranium for different MOX fuel loading fractions and irradiating conditions. (author)

Disturbances in equilibrium function after major earthquake.

Science.gov (United States)

Honma, Motoyasu; Endo, Nobutaka; Osada, Yoshihisa; Kim, Yoshiharu; Kuriyama, Kenichi

2012-01-01

Major earthquakes were followed by a large number of aftershocks and significant outbreaks of dizziness occurred over a large area. However it is unclear why major earthquake causes dizziness. We conducted an intergroup trial on equilibrium dysfunction and psychological states associated with equilibrium dysfunction in individuals exposed to repetitive aftershocks versus those who were rarely exposed. Greater equilibrium dysfunction was observed in the aftershock-exposed group under conditions without visual compensation. Equilibrium dysfunction in the aftershock-exposed group appears to have arisen from disturbance of the inner ear, as well as individual vulnerability to state anxiety enhanced by repetitive exposure to aftershocks. We indicate potential effects of autonomic stress on equilibrium function after major earthquake. Our findings may contribute to risk management of psychological and physical health after major earthquakes with aftershocks, and allow development of a new empirical approach to disaster care after such events.

Suspension hydration of tricalcium silicate at constant pH. I. Variation of particle size and tricalcium silicate content

NARCIS (Netherlands)

McCurdy, K.G.; Stein, H.N.

1973-01-01

Calcium and silicate ion concentrations during suspension hydration of C3S indicate that at pH 11.5 an equilibrium is established between one of the hydrates and the solution during about 80 minutes. The concentrations found in this period are indipendent of the particle size of the C3S and (within

Do intertidal flats ever reach equilibrium?

NARCIS (Netherlands)

Maan, D.C.; van Prooijen, B.C.; Wang, Z.B.; de Vriend, H.J.

2015-01-01

Various studies have identified a strong relation between the hydrodynamic forces and the equilibrium profile for intertidal flats. A thorough understanding of the interplay between the hydrodynamic forces and the morphology, however, concerns more than the equilibrium state alone. We study the

A nonlinear model for myogenic regulation of blood flow to bone: equilibrium states and stability characteristics.

Science.gov (United States)

Harrigan, T P

1996-01-01

A simple compartmental model for myogenic regulation of interstitial pressure in bone is developed, and the interaction between changes in interstitial pressure and changes in arterial and venous resistance is studied. The arterial resistance is modeled by a myogenic model that depends on transmural pressure, and the venous resistance is modeled by using a vascular waterfall. Two series capacitances model blood storage in the vascular system and interstitial fluid storage in the extravascular space. The static results mimic the observed effect that vasodilators work less well in bone than do vasoconstrictors. The static results also show that the model gives constant flow rates over a limited range of arterial pressure. The dynamic model shows unstable behavior at small values of bony capacitance and at high enough myogenic gain. At low myogenic gain, only a single equilibrium state is present, but a high enough myogenic gain, two new equilibrium states appear. At additional increases in gain, one of the two new states merges with and then separates from the original state, and the original state becomes a saddle point. The appearance of the new states and the transition of the original state to a saddle point do not depend on the bony capacitance, and these results are relevant to general fluid compartments. Numerical integration of the rate equations confirms the stability calculations and shows limit cycling behavior in several situations. The relevance of this model to circulation in bone and to other compartments is discussed.

Scaling of the space-time correlation function of particle currents in a suspension of hard-sphere-like particles: exposing when the motion of particles is Brownian.

Science.gov (United States)

van Megen, W; Martinez, V A; Bryant, G

2009-12-18

The current correlation function is determined from dynamic light scattering measurements of a suspension of particles with hard spherelike interactions. For suspensions in thermodynamic equilibrium we find scaling of the space and time variables of the current correlation function. This finding supports the notion that the movement of suspended particles can be described in terms of uncorrelated Brownian encounters. However, in the metastable fluid, at volume fractions above freezing, this scaling fails.

78 FR 35533 - Suspension of Limitations Under the Jerusalem Embassy Act

Science.gov (United States)

2013-06-12

...-09 of June 4, 2013--Suspension of Limitations Under the Jerusalem Embassy Act Presidential.... 2013-09 of June 4, 2013 Suspension of Limitations Under the Jerusalem Embassy Act Memorandum for the... the United States, including section 7(a) of the Jerusalem Embassy Act of 1995 (Public Law 104-45...

A reduction method for phase equilibrium calculations with cubic equations of state

Directory of Open Access Journals (Sweden)

D. V. Nichita

2006-09-01

Full Text Available In this work we propose a new reduction method for phase equilibrium calculations using a general form of cubic equations of state (CEOS. The energy term in the CEOS is a quadratic form, which is diagonalized by applying a linear transformation. The number of the reduction parameters is related to the rank of the matrix C with elements (1-Cij, where Cij denotes the binary interaction parameters (BIPs. The dimensionality of the problem depends only on the number of reduction parameters, and is independent of the number of components in the mixture.

Equilibrium state analysis of a nonneutral plasma under a uniform magnetic field

International Nuclear Information System (INIS)

Fernandez, J.E.; Molinari, V.G.; Sumini, M.A.

1990-01-01

By recourse to the Boltzmann H-theorem, the existence of a thermodynamic equilibrium state has been proved for a nonneutral plasma under an external magnetic field. The equation describing the density profile of ions or electrons has been found. The density equation has been numerically solved for a generic magnetic field and plasma frequency, giving a parametric limit for the confinement region. An appropriate change of variable allows to approximate the density equation whose analytical solution has been found. The approximated density closely fits the numerical solution of the original equation. (Author)

The average equilibrium charge-states of heavy ions with Z > 60 stripped in He and H2

International Nuclear Information System (INIS)

Oganessian, Yu.T.; Lobanov, Yu.V.; Popeko, A.G.; Abdullin, F.Sh.; Kharitonov, Yu.P.; Ledovskoy, A.A.; Tsyganov, Yu.S.

1991-01-01

The equilibrium charges of heavy ions (61 < Z < 101) with energies from 5 to 100 MeV stripped in He and H2 have been measured. New empirical formulae for the average charge state are presented. (orig.)

Numerical study of spherical Torus MHD equilibrium configuration

International Nuclear Information System (INIS)

Cheng Faying; Dong Jiaqi; Wang Aike

2003-01-01

Tokamak equilibrium code SWEQU has been modified so that it can be used for the MHD equilibrium study of low aspect ratio device. Evolution of plasma configuration in start-up phase and double-null divertor configuration in steady-state phase has been simulated using the modified code. Results show that the new code can be used not only to obtain the equilibrium configuration of spherical Torus in steady-state phase, but also to simulate the evolution of plasma in the start-up phase

Out-of-equilibrium processes in suspensions of oppositely charged colloids: liquid-to-crystal nucleation and gel formation

Science.gov (United States)

Sanz, Eduardo

2009-03-01

We study the kinetics of the liquid-to-crystal transformation and of gel formation in colloidal suspensions of oppositely charged particles. We analyse, by means of both computer simulations and experiments, the evolution of a fluid quenched to a state point of the phase diagram where the most stable state is either a homogeneous crystalline solid or a solid phase in contact with a dilute gas. On the one hand, at high temperatures and high packing fractions, close to an ordered-solid/disordered-solid coexistence line, we find that the fluid-to-crystal pathway does not follow the minimum free energy route. On the other hand, a quench to a state point far from the ordered-crystal/disordered-crystal coexistence border is followed by a fluid-to-solid transition through the minimum free energy pathway. At low temperatures and packing fractions we observe that the system undergoes a gas-liquid spinodal decomposition that, at some point, arrests giving rise to a gel-like structure. Both our simulations and experiments suggest that increasing the interaction range favors crystallization over vitrification in gel-like structures. [4pt] In collaboration with Chantal Valeriani, Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands and SUPA, School of Physics, University of Edinburgh, JCMB King's Buildings, Mayfield Road, Edinburgh EH9 3JZ, UK; Teun Vissers, Andrea Fortini, Mirjam E. Leunissen, and Alfons van Blaaderen, Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University; Daan Frenke, FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands and Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK; and Marjolein Dijkstra, Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University.

Absorption Spectra of Gold Nanoparticle Suspensions

Science.gov (United States)

Anan'eva, M. V.; Nurmukhametov, D. R.; Zverev, A. S.; Nelyubina, N. V.; Zvekov, A. A.; Russakov, D. M.; Kalenskii, A. V.; Eremenko, A. N.

2018-02-01

Three gold nanoparticle suspensions are obtained, and mean radii in distributions - (6.1 ± 0.2), (11.9 ± 0.3), and (17.3 ± 0.7) nm - are determined by the transmission electron microscopy method. The optical absorption spectra of suspensions are obtained and studied. Calculation of spectral dependences of the absorption index of suspensions at values of the gold complex refractive index taken from the literature showed a significant deviation of experimental and calculated data in the region of 450-800 nm. Spectral dependences of the absorption of suspensions are simulated within the framework of the Mie-Drude theory taking into account the interband absorption in the form of an additional term in the imaginary part of the dielectric permittivity of the Gaussian type. It is shown that to quantify the spectral dependences in the region of the plasmon absorption band of nanoparticles, correction of the parameters of the interband absorption is necessary in addition to the increase of the relaxation parameter of the Drude theory. Spectral dependences of the dielectric permittivity of gold in nanodimensional state are refined from the solution of the inverse problem. The results of the present work are important for predicting the special features of operation of photonic devices and optical detonators based on gold nanoparticles.

Transition from thermal to turbulent equilibrium with a resulting electromagnetic spectrum

Energy Technology Data Exchange (ETDEWEB)

Ziebell, L. F., E-mail: luiz.ziebell@ufrgs.br [Instituto de Física, UFRGS, Porto Alegre, RS (Brazil); Yoon, P. H. [Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States); School of Space Research, Kyung Hee University, Yongin, Gyeonggi 446-701 (Korea, Republic of); Gaelzer, R. [Instituto de Física, UFRGS, Porto Alegre, RS (Brazil); Instituto de Física e Matemática, UFPel, Pelotas, RS (Brazil); Pavan, J. [Instituto de Física e Matemática, UFPel, Pelotas, RS (Brazil)

2014-01-15

A recent paper [Ziebell et al., Phys. Plasmas 21, 010701 (2014)] discusses a new type of radiation emission process for plasmas in a state of quasi-equilibrium between the particles and enhanced Langmuir turbulence. Such a system may be an example of the so-called “turbulent quasi-equilibrium.” In the present paper, it is shown on the basis of electromagnetic weak turbulence theory that an initial thermal equilibrium state (i.e., only electrostatic fluctuations and Maxwellian particle distributions) transitions toward the turbulent quasi-equilibrium state with enhanced electromagnetic radiation spectrum, thus demonstrating that the turbulent quasi-equilibrium discussed in the above paper correctly describes the weakly turbulent plasma dynamically interacting with electromagnetic fluctuations, while maintaining a dynamical steady-state in the average sense.

Immunity by equilibrium.

Science.gov (United States)

Eberl, Gérard

2016-08-01

The classical model of immunity posits that the immune system reacts to pathogens and injury and restores homeostasis. Indeed, a century of research has uncovered the means and mechanisms by which the immune system recognizes danger and regulates its own activity. However, this classical model does not fully explain complex phenomena, such as tolerance, allergy, the increased prevalence of inflammatory pathologies in industrialized nations and immunity to multiple infections. In this Essay, I propose a model of immunity that is based on equilibrium, in which the healthy immune system is always active and in a state of dynamic equilibrium between antagonistic types of response. This equilibrium is regulated both by the internal milieu and by the microbial environment. As a result, alteration of the internal milieu or microbial environment leads to immune disequilibrium, which determines tolerance, protective immunity and inflammatory pathology.

On solutions to equilibrium problems for systems of stiffened gases

OpenAIRE

Flåtten, Tore; Morin, Alexandre; Munkejord, Svend Tollak

2011-01-01

We consider an isolated system of N immiscible fluids, each following a stiffened-gas equation of state. We consider the problem of calculating equilibrium states from the conserved fluid-mechanical properties, i.e., the partial densities and internal energies. We consider two cases; in each case mechanical equilibrium is assumed, but the fluids may or may not be in thermal equilibrium. For both cases, we address the issues of existence, uniqueness, and physical validity of equilibrium soluti...

On the local equilibrium condition

International Nuclear Information System (INIS)

Hessling, H.

1994-11-01

A physical system is in local equilibrium if it cannot be distinguished from a global equilibrium by ''infinitesimally localized measurements''. This should be a natural characterization of local equilibrium, but the problem is to give a precise meaning to the qualitative phrase ''infinitesimally localized measurements''. A solution is suggested in form of a Local Equilibrium Condition (LEC), which can be applied to linear relativistic quantum field theories but not directly to selfinteracting quantum fields. The concept of local temperature resulting from LEC is compared to an old approach to local temperature based on the principle of maximal entropy. It is shown that the principle of maximal entropy does not always lead to physical states if it is applied to relativistic quantum field theories. (orig.)

Educational Lynching: Critical Race Theory and the Suspension of Black Boys

Science.gov (United States)

Payne, Macheo

2010-01-01

Looking at the disproportionate suspension of African American, Black male students through the lens of critical race theory, this presents arguments from a CRT how the disproportionate suspension of Black male students is rooted in white supremacy and racist policy in the United States. Local recommendations are offered for Oakland Unified School…

76 FR 82071 - Suspension of Limitations Under the Jerusalem Embassy Act

Science.gov (United States)

2011-12-29

.... 2012-03 of December 2, 2011--Suspension of Limitations Under the Jerusalem Embassy Act #0; #0; #0.... 2012-03 of December 2, 2011 Suspension of Limitations Under the Jerusalem Embassy Act Memorandum for... laws of the United States, including section 7(a) of the Jerusalem Embassy Act of 1995 (Public Law 104...

77 FR 74551 - Suspension of Limitations Under the Jerusalem Embassy Act

Science.gov (United States)

2012-12-14

.... 2013-2 of December 4, 2012--Suspension of Limitations Under the Jerusalem Embassy Act #0; #0; #0.... 2013-2 of December 4, 2012 Suspension of Limitations Under the Jerusalem Embassy Act Memorandum for the... the United States, including section 7(a) of the Jerusalem Embassy Act of 1995 (Public Law 104-45...

A second perspective on the Amann–Schmiedl–Seifert criterion for non-equilibrium in a three-state system

International Nuclear Information System (INIS)

Jia, Chen; Chen, Yong

2015-01-01

In the work of Amann, Schmiedl and Seifert (2010 J. Chem. Phys. 132 041102), the authors derived a sufficient criterion to identify a non-equilibrium steady state (NESS) in a three-state Markov system based on the coarse-grained information of two-state trajectories. In this paper, we present a mathematical derivation and provide a probabilistic interpretation of the Amann–Schmiedl–Seifert (ASS) criterion. Moreover, the ASS criterion is compared with some other criterions for a NESS. (paper)

Structure and dynamics of soft repulsive colloidal suspensions in the vicinity of the glass transition.

Science.gov (United States)

Crassous, Jérôme J; Casal-Dujat, Lucia; Medebach, Martin; Obiols-Rabasa, Marc; Vincent, Romaric; Reinhold, Frank; Boyko, Volodymyr; Willerich, Immanuel; Menzel, Andreas; Moitzi, Christian; Reck, Bernd; Schurtenberger, Peter

2013-08-20

We use a combination of different scattering techniques and rheology to highlight the link between structure and dynamics of dense aqueous suspensions of soft repulsive colloids in the vicinity of a glass transition. Three different latex formulations with an increasing amount of the hydrophilic component resulting in either purely electrostatically or electrosterically stabilized suspensions are investigated. From the analysis of the static structure factor measured by small-angle X-ray scattering, we derive an effective volume fraction that includes contributions from interparticle interactions. We further investigate the dynamics of the suspensions using 3D cross-correlation dynamic light scattering (3DDLS) and rheology. We analyze the data using an effective hard sphere model and in particular compare the linear viscoelasticity and flow behavior to the predictions of mode coupling theory, which accounts for a purely kinetic glass transition determined by the equilibrium structure factor. We demonstrate that seemingly very different colloidal systems exhibit the same generic behavior when the effects from interparticle interactions are incorporated using an effective volume fraction description.

Equilibrium and off-equilibrium trap-size scaling in one-dimensional ultracold bosonic gases

International Nuclear Information System (INIS)

Campostrini, Massimo; Vicari, Ettore

2010-01-01

We study some aspects of equilibrium and off-equilibrium quantum dynamics of dilute bosonic gases in the presence of a trapping potential. We consider systems with a fixed number of particles and study their scaling behavior with increasing the trap size. We focus on one-dimensional bosonic systems, such as gases described by the Lieb-Liniger model and its Tonks-Girardeau limit of impenetrable bosons, and gases constrained in optical lattices as described by the Bose-Hubbard model. We study their quantum (zero-temperature) behavior at equilibrium and off equilibrium during the unitary time evolution arising from changes of the trapping potential, which may be instantaneous or described by a power-law time dependence, starting from the equilibrium ground state for an initial trap size. Renormalization-group scaling arguments and analytical and numerical calculations show that the trap-size dependence of the equilibrium and off-equilibrium dynamics can be cast in the form of a trap-size scaling in the low-density regime, characterized by universal power laws of the trap size, in dilute gases with repulsive contact interactions and lattice systems described by the Bose-Hubbard model. The scaling functions corresponding to several physically interesting observables are computed. Our results are of experimental relevance for systems of cold atomic gases trapped by tunable confining potentials.

Non-equilibrium thermodynamics, maximum entropy production and Earth-system evolution.

Science.gov (United States)

Kleidon, Axel

2010-01-13

The present-day atmosphere is in a unique state far from thermodynamic equilibrium. This uniqueness is for instance reflected in the high concentration of molecular oxygen and the low relative humidity in the atmosphere. Given that the concentration of atmospheric oxygen has likely increased throughout Earth-system history, we can ask whether this trend can be generalized to a trend of Earth-system evolution that is directed away from thermodynamic equilibrium, why we would expect such a trend to take place and what it would imply for Earth-system evolution as a whole. The justification for such a trend could be found in the proposed general principle of maximum entropy production (MEP), which states that non-equilibrium thermodynamic systems maintain steady states at which entropy production is maximized. Here, I justify and demonstrate this application of MEP to the Earth at the planetary scale. I first describe the non-equilibrium thermodynamic nature of Earth-system processes and distinguish processes that drive the system's state away from equilibrium from those that are directed towards equilibrium. I formulate the interactions among these processes from a thermodynamic perspective and then connect them to a holistic view of the planetary thermodynamic state of the Earth system. In conclusion, non-equilibrium thermodynamics and MEP have the potential to provide a simple and holistic theory of Earth-system functioning. This theory can be used to derive overall evolutionary trends of the Earth's past, identify the role that life plays in driving thermodynamic states far from equilibrium, identify habitability in other planetary environments and evaluate human impacts on Earth-system functioning. This journal is © 2010 The Royal Society

Self-assembled materials and supramolecular chemistry within microfluidic environments: from common thermodynamic states to non-equilibrium structures.

Science.gov (United States)

Sevim, S; Sorrenti, A; Franco, C; Furukawa, S; Pané, S; deMello, A J; Puigmartí-Luis, J

2018-05-01

Self-assembly is a crucial component in the bottom-up fabrication of hierarchical supramolecular structures and advanced functional materials. Control has traditionally relied on the use of encoded building blocks bearing suitable moieties for recognition and interaction, with targeting of the thermodynamic equilibrium state. On the other hand, nature leverages the control of reaction-diffusion processes to create hierarchically organized materials with surprisingly complex biological functions. Indeed, under non-equilibrium conditions (kinetic control), the spatio-temporal command of chemical gradients and reactant mixing during self-assembly (the creation of non-uniform chemical environments for example) can strongly affect the outcome of the self-assembly process. This directly enables a precise control over material properties and functions. In this tutorial review, we show how the unique physical conditions offered by microfluidic technologies can be advantageously used to control the self-assembly of materials and of supramolecular aggregates in solution, making possible the isolation of intermediate states and unprecedented non-equilibrium structures, as well as the emergence of novel functions. Selected examples from the literature will be used to confirm that microfluidic devices are an invaluable toolbox technology for unveiling, understanding and steering self-assembly pathways to desired structures, properties and functions, as well as advanced processing tools for device fabrication and integration.

Mapping Isobaric Aging onto the Equilibrium Phase Diagram

DEFF Research Database (Denmark)

Niss, Kristine

2017-01-01

The linear volume relaxation and the nonlinear volume aging of a glass-forming liquid are measured, directly compared, and used to extract the out-of-equilibrium relaxation time. This opens a window to investigate how the relaxation time depends on temperature, structure, and volume in parts...... of phase space that are not accessed by the equilibrium liquid. It is found that the temperature dependence of relaxation time is non-Arrhenius even in the isostructural case—challenging the Adam-Gibbs entropy model. Based on the presented data and the idea that aging happens through quasiequilibrium...... states, we suggest a mapping of the out-of-equilibrium states during isobaric aging to the equilibrium phase diagram. This mapping implies the existence of isostructural lines in the equilibrium phase diagram. The relaxation time is found to depend on the bath temperature, density, and a just single...

Equilibrium distribution function in collisionless systems

International Nuclear Information System (INIS)

Pergamenshchik, V.M.

1988-01-01

Collisionless systems of a large number of N particles interacting by Coulomb forces are widely spread in cosmic and laboratory plasma. A statistical theory of equilibrium state of collisionless Coulomb systems which evolution obeys Vlasov equation is proposed. The developed formalism permits a sequential consideration of such distributed in one-particle six-dimensional phase space of a system and to obtain a simple result: equilibrium distribution function has the form of Fermi-Dirac distribution and doesn't depend on initial state factors

Stability of allopurinol and of five antineoplastics in suspension.

Science.gov (United States)

Dressman, J B; Poust, R I

1983-04-01

The stability of allopurinol, azathioprine, chlorambucil, melphalan, mercaptopurine, and thioguanine each in an extemporaneously prepared suspension was studied. Tablets of each drug were crushed, mixed with a suspending agent, and brought to a final volume of 10, 15, or 20 ml with a 2:1 mixture of simple syrup and wild cherry syrup. Suspensions were prepared in the following concentrations: allopurinol (20 mg/ml), azathioprine (50 mg/ml), chlorambucil (2 mg/ml), melphalan (2 mg/ml), mercaptopurine (50 mg/ml), and thioguanine (40 mg/ml). Using high-performance liquid chromatography or ultraviolet scans, duplicate assays were performed on each suspension periodically during storage for up to 84 days at ambient room temperature or 5 degrees C. The time required for the suspensions to drop below 90% of labeled strength was used as an indicator of drug stability. Allopurinol and azathioprine were stable for at least 56 days at room temperature and at 5 degrees C. Chlorambucil decomposed rapidly at room temperature but was stable for seven days when stored at 5 degrees C. Melphalan suspensions did not meet the stated criteria for stability even at the time of initial assay. Mercaptopurine and thioguanine were stable for 14 and 84 days, respectively, at room temperature; at 5 degrees C, assay values dropped below those obtained at room temperature. In the suspension formulation tested, allopurinol, azathioprine, mercaptopurine, and thioguanine are stable for at least 14 days at room temperature; chlorambucil suspensions should be refrigerated and discarded after seven days. Melphalan decomposes too rapidly to make this suspension formulation feasible for extemporaneous compounding.

A study on the criticality search of transuranium recycling BWR core by adjusting supplied fuel composition in equilibrium state

International Nuclear Information System (INIS)

Seino, Takeshi; Sekimoto, Hiroshi

1998-01-01

There have been some difficulties in carrying out an extensive evaluation of the equilibrium state of Light Water Reactor (LWR) recycling operations keeping their fixed criticality condition using conventional design codes because of the complexity of their calculation model for practical fuel and core design and because of a large amount of calculation time. This study presents an efficient approach to secure the criticality in an equilibrium cycle by adjusting a supplied fuel composition. The criticality search is performed by the use of fuel importance obtained from the equation adjoint to a continuously fuel supplied core burnup equation. Using this method, some numerical analyses were carried out in order to evaluate the mixed oxide (MOX) fuel composition of equilibrium Boiling Water Reactor (BWR) cores satisfying the criticality requirement. The results showed the comprehensive and quantitative characteristics on the equilibrium cores confining transuraniums for different MOX fuel loading fractions and irradiating conditions

A study on the stability of a motorcycle wheel-swingarm suspension with chain transmission

Science.gov (United States)

Sorrentino, S.; Leonelli, L.

2017-11-01

The present study describes a possible driving mechanism for a self-excited oscillation observed in motorcycle dynamics, often referred to as chatter. This phenomenon, affecting the performance of road racing motorcycles, has been simulated in straight running braking manoeuvres with multibody motorcycle models. It involves rear suspension bounce and driveline oscillation in the frequency range between 17 and 22 Hz. A simplified model of a motorcycle rear suspension with chain transmission is proposed and its stability in equilibrium configurations is studied via eigenvalue analysis. The sensitivity with respect to all its governing parameters is analysed by means of stability maps and the self-excitation mechanism is explained with the aid of energy balance analysis and phase diagrams. It is found that the key role for the instability onset is played by the gradient of the nonlinear characteristic slip function of the tyre.

A cosmic equation of state for the inhomogeneous universe: can a global far-from-equilibrium state explain dark energy?

International Nuclear Information System (INIS)

Buchert, Thomas

2005-01-01

A system of effective Einstein equations for spatially averaged scalar variables of inhomogeneous cosmological models can be solved by providing a 'cosmic equation of state'. Recent efforts to explain dark energy focus on 'backreaction effects' of inhomogeneities on the effective evolution of cosmological parameters in our Hubble volume, avoiding a cosmological constant in the equation of state. In this letter, it is argued that if kinematical backreaction effects are indeed of the order of the averaged density (or larger as needed for an accelerating domain of the universe), then the state of our regional Hubble volume would have to be in the vicinity of a far-from-equilibrium state that balances kinematical backreaction and average density. This property, if interpreted globally, is shared by a stationary cosmos with effective equation of state p eff = -1/3 ρ eff . It is concluded that a confirmed explanation of dark energy by kinematical backreaction may imply a paradigmatic change of cosmology. (letter to the editor)

Existence of equilibrium states of hollow elastic cylinders submerged in a fluid

Directory of Open Access Journals (Sweden)

M. B. M. Elgindi

1992-01-01

Full Text Available This paper is concerned with the existence of equilibrium states of thin-walled elastic, cylindrical shell fully or partially submerged in a fluid. This problem obviously serves as a model for many problems with engineering importance. Previous studies on the deformation of the shell have assumed that the pressure due to the fluid is uniform. This paper takes into consideration the non-uniformity of the pressure by taking into account the effect of gravity. The presence of a pressure gradient brings additional parameters to the problem which in turn lead to the consideration of several boundary value problems.

Identifying apparent local stable isotope equilibrium in a complex non-equilibrium system.

Science.gov (United States)

He, Yuyang; Cao, Xiaobin; Wang, Jianwei; Bao, Huiming

2018-02-28

Although being out of equilibrium, biomolecules in organisms have the potential to approach isotope equilibrium locally because enzymatic reactions are intrinsically reversible. A rigorous approach that can describe isotope distribution among biomolecules and their apparent deviation from equilibrium state is lacking, however. Applying the concept of distance matrix in graph theory, we propose that apparent local isotope equilibrium among a subset of biomolecules can be assessed using an apparent fractionation difference (|Δα|) matrix, in which the differences between the observed isotope composition (δ') and the calculated equilibrium fractionation factor (1000lnβ) can be more rigorously evaluated than by using a previous approach for multiple biomolecules. We tested our |Δα| matrix approach by re-analyzing published data of different amino acids (AAs) in potato and in green alga. Our re-analysis shows that biosynthesis pathways could be the reason for an apparently close-to-equilibrium relationship inside AA families in potato leaves. Different biosynthesis/degradation pathways in tubers may have led to the observed isotope distribution difference between potato leaves and tubers. The analysis of data from green algae does not support the conclusion that AAs are further from equilibrium in glucose-cultured green algae than in the autotrophic ones. Application of the |Δα| matrix can help us to locate potential reversible reactions or reaction networks in a complex system such as a metabolic system. The same approach can be broadly applied to all complex systems that have multiple components, e.g. geochemical or atmospheric systems of early Earth or other planets. Copyright © 2017 John Wiley & Sons, Ltd.

A Strategic-Equilibrium Based

Directory of Open Access Journals (Sweden)

Gabriel J. Turbay

2011-03-01

Full Text Available The strategic equilibrium of an N-person cooperative game with transferable utility is a system composed of a cover collection of subsets of N and a set of extended imputations attainable through such equilibrium cover. The system describes a state of coalitional bargaining stability where every player has a bargaining alternative against any other player to support his corresponding equilibrium claim. Any coalition in the sable system may form and divide the characteristic value function of the coalition as prescribed by the equilibrium payoffs. If syndicates are allowed to form, a formed coalition may become a syndicate using the equilibrium payoffs as disagreement values in bargaining for a part of the complementary coalition incremental value to the grand coalition when formed. The emergent well known-constant sum derived game in partition function is described in terms of parameters that result from incumbent binding agreements. The strategic-equilibrium corresponding to the derived game gives an equal value claim to all players.  This surprising result is alternatively explained in terms of strategic-equilibrium based possible outcomes by a sequence of bargaining stages that when the binding agreements are in the right sequential order, von Neumann and Morgenstern (vN-M non-discriminatory solutions emerge. In these solutions a preferred branch by a sufficient number of players is identified: the weaker players syndicate against the stronger player. This condition is referred to as the stronger player paradox.  A strategic alternative available to the stronger players to overcome the anticipated not desirable results is to voluntarily lower his bargaining equilibrium claim. In doing the original strategic equilibrium is modified and vN-M discriminatory solutions may occur, but also a different stronger player may emerge that has eventually will have to lower his equilibrium claim. A sequence of such measures converges to the equal

Mapping Isobaric Aging onto the Equilibrium Phase Diagram.

Science.gov (United States)

Niss, Kristine

2017-09-15

The linear volume relaxation and the nonlinear volume aging of a glass-forming liquid are measured, directly compared, and used to extract the out-of-equilibrium relaxation time. This opens a window to investigate how the relaxation time depends on temperature, structure, and volume in parts of phase space that are not accessed by the equilibrium liquid. It is found that the temperature dependence of relaxation time is non-Arrhenius even in the isostructural case-challenging the Adam-Gibbs entropy model. Based on the presented data and the idea that aging happens through quasiequilibrium states, we suggest a mapping of the out-of-equilibrium states during isobaric aging to the equilibrium phase diagram. This mapping implies the existence of isostructural lines in the equilibrium phase diagram. The relaxation time is found to depend on the bath temperature, density, and a just single structural parameter, referred to as an effective temperature.

Diffusion in coronas around clinopyroxene: modelling with local equilibrium and steady state, and a non-steady-state modification to account for zoned actinolite-hornblende

Science.gov (United States)

Ashworth, J. R.; Birdi, J. J.; Emmett, T. F.

1992-01-01

Retrograde coronas of Caledonian age, between clinopyroxene and plagioclase in the Jotun Nappe Complex, Norway, illustrate the effects of diffusion kinetics on mineral distributions among layers and on the compositions of hornblende-actinolite. One corona type comprises a symplectite of epidote + quartz adjacent to plagioclase, and a less well-organized intergrowth of amphibole + quartz replacing clinopyroxene. The observed mineral proportions imply an open-system reaction, but the similarity of Al/Si ratios in reactant plagioclase and product symplectite indicates approximate conservation of Al2O3 and SiO2. The largest inferred open-system flux is a loss of CaO, mostly derived from consumption of clinopyroxene. The approximate layer structure, Pl|Ep + Qtz|Hbl + Qtz|Act±Hbl + Qtz|Cpx, is modelled using the theory of steady-state diffusion-controlled growth with local equilibrium. To obtain a solution, it is necessary to use a reactant plagioclase composition which takes into account aluminous (epidote) inclusions. The results indicate that, in terms of Onsager diffusion coefficients L ii , Ca is more mobile than AL ( L CaCa/ L AlAl≳3.) (where ≳ means greater than or approximately equal to). This behaviour of Ca is comparable with that of Mg in previously studied coronas around olivine. Si is non-diffusing in the present modelling, because of silica saturation. Oxidation of some Fe2+ to Fe3+ occurs within the corona. Mg diffuses towards its source (clinopyroxene) to maintain local equilibrium. Other coronas consist of two layers, hornblende adjacent to plagioclase and zoned amphibole + quartz adjacent to clinopyroxene. In the zoned layer, actinolitic hornblende forms relict patches, separated from quartz blebs by more aluminous hornblende. A preliminary steady-state, local-equilibrium model of grain-boundary diffusion explains the formation of low-Al and high-Al layers as due to Al immobility. Zoning and replacement are qualitatively explained in terms of

Hydropneumatic suspension systems

Energy Technology Data Exchange (ETDEWEB)

Bauer, Wolfgang

2011-07-01

Hydropneumatic suspensions systems combine the excellent properties of gas springs with the favourable damping properties of hydraulic fluids. The advantages of these systems are particularly appropriate for automotive applications, such as passenger cars, trucks and agricultural equipment. In this book, Dr. Bauer provides an extensive overview of hydropneumatic suspension systems. Starting with a comparison of different types of suspension systems, the author subsequently describes the theoretical background associated with spring and damping characteristics of hydropneumatic systems and furthermore explains the design of the most important system components. Additionally he gives an overview of level control systems and various special functions. Finally the technology is illustrated by design examples and the outlook for future hydropneumatic suspensions is discussed. (orig.)

A new estimation method for nuclide number densities in equilibrium cycle

International Nuclear Information System (INIS)

Seino, Takeshi; Sekimoto, Hiroshi; Ando, Yoshihira.

1997-01-01

A new method is proposed for estimating nuclide number densities of LWR equilibrium cycle by multi-recycling calculation. Conventionally, it is necessary to spend a large computation time for attaining the ultimate equilibrium state. Hence, the cycle in nearly constant fuel composition has been considered as an equilibrium state which can be achieved by a few of recycling calculations on a simulated cycle operation under a specific fuel core design. The present method uses steady state fuel nuclide number densities as the initial guess for multi-recycling burnup calculation obtained by a continuously fuel supplied core model. The number densities are modified to be the initial number densities for nuclides of a batch supplied fuel. It was found that the calculated number densities could attain to more precise equilibrium state than that of a conventional multi-recycling calculation with a small number of recyclings. In particular, the present method could give the ultimate equilibrium number densities of the nuclides with the higher mass number than 245 Cm and 244 Pu which were not able to attain to the ultimate equilibrium state within a reasonable number of iterations using a conventional method. (author)

Comments on equilibrium, transient equilibrium, and secular equilibrium in serial radioactive decay

International Nuclear Information System (INIS)

Prince, J.R.

1979-01-01

Equations describing serial radioactive decay are reviewed along with published descriptions or transient and secular equilibrium. It is shown that terms describing equilibrium are not used in the same way by various authors. Specific definitions are proposed; they suggest that secular equilibrium is a subset of transient equilibrium

Non-equilibrium dynamics of one-dimensional Bose gases

International Nuclear Information System (INIS)

Langen, T.

2013-01-01

Understanding the non-equilibrium dynamics of isolated quantum many-body systems is an open problem on vastly different energy, length, and time scales. Examples range from the dynamics of the early universe and heavy-ion collisions to the subtle coherence and transport properties in condensed matter physics. However, realizations of such quantum many-body systems, which are both well isolated from the environment and accessible to experimental study are scarce. This thesis presents a series of experiments with ultracold one-dimensional Bose gases. These gases combine a nearly perfect isolation from the environment with many well-established methods to manipulate and probe their quantum states. This makes them an ideal model system to explore the physics of quantum many body systems out of equilibrium. In the experiments, a well-defined non-equilibrium state is created by splitting a single one-dimensional gas coherently into two parts. The relaxation of this state is probed using matter-wave interferometry. The Observations reveal the emergence of a prethermalized steady state which differs strongly from thermal equilibrium. Such thermal-like states had previously been predicted for a large variety of systems, but never been observed directly. Studying the relaxation process in further detail shows that the thermal correlations of the prethermalized state emerge locally in their final form and propagate through the system in a light-cone-like evolution. This provides first experimental evidence for the local relaxation conjecture, which links relaxation processes in quantum many-body systems to the propagation of correlations. Furthermore, engineering the initial state of the evolution demonstrates that the prethermalized state is described by a generalized Gibbs ensemble, an observation which substantiates the importance of this ensemble as an extension of standard statistical mechanics. Finally, an experiment is presented, where pairs of gases with an atom

Particle interactions in concentrated suspensions

International Nuclear Information System (INIS)

Mondy, L.A.; Graham, A.L.; Abbott, J.R.; Brenner, H.

1993-01-01

An overview is presented of research that focuses on slow flows of suspensions in which colloidal and inertial effects are negligibly small. The authors describe nuclear magnetic resonance imaging experiments to quantitatively measure particle migration occurring in concentrated suspensions undergoing a flow with a nonuniform shear rate. These experiments address the issue of how the flow field affects the microstructure of suspensions. In order to understand the local viscosity in a suspension with such a flow-induced, spatially varying concentration, one must know how the viscosity of a homogeneous suspension depends on such variables as solids concentration and particle orientation. The authors suggest the technique of falling ball viscometry, using small balls, as a method to determine the effective viscosity of a suspension without affecting the original microstructure significantly. They also describe data from experiments in which the detailed fluctuations of a falling ball's velocity indicate the noncontinuum nature of the suspension and may lead to more insights into the effects of suspension microstructure on macroscopic properties. Finally, they briefly describe other experiments that can be performed in quiescent suspensions (in contrast to the use of conventional shear rotational viscometers) in order to learn more about boundary effects in concentrated suspensions

Experimental investigation of supercurrent enhancement in S-N-S junctions by non-equilibrium injection into supercurrent-carrying bound Andreev states

DEFF Research Database (Denmark)

Kutchinsky, Jonatan; Taboryski, Rafael Jozef; Sørensen, C B

2001-01-01

We report measurements on three-terminal superconductor-semiconductor-superconductor injection devices demonstrating enhancement of the supercurrent by injection from a superconducting injector electrode. Two other electrodes were used to form the detector junction. Applying a small voltage...... of enhancement of the supercurrent by non-equilibrium injection into bound supercurrent-carrying Andreev states. The effect persists to temperatures where the equilibrium supercurrent has vanished. (C) 2001 Elsevier Science B.V. All rights reserved....

Self-powered suspension criterion and energy regeneration implementation scheme of motor-driven active suspension

Science.gov (United States)

Yan, Shuai; Sun, Weichao

2017-09-01

Active suspension systems have advantages on mitigating the effects of vehicle vibration caused by road roughness, which are one of the most important component parts in influencing the performances of vehicles. However, high amount of energy consumption restricts the application of active suspension systems. From the point of energy saving, this paper presents a self-powered criterion of the active suspension system to judge whether a motor-driven suspension can be self-powered or not, and then a motor parameter condition is developed as a reference to design a self-powered suspension. An energy regeneration implementation scheme is subsequently proposed to make the active suspension which has the potential to be self-powered achieve energy-saving target in the real application. In this implementation scheme, operating electric circuits are designed based on different working status of the actuator and power source and it is realizable to accumulate energy from road vibration and supply energy to the actuator by switching corresponding electric circuits. To apply the self-powered suspension criterion and energy regeneration implementation scheme, an active suspension system is designed with a constrained H∞ controller and calculation results indicate that it has the capability to be self-powered. Simulation results show that the performances of the self-powered active suspension are nearly the same as those of the active suspension with an external energy source and can achieve energy regeneration at the same time.

Relevance of equilibrium in multifragmentation

International Nuclear Information System (INIS)

Furuta, Takuya; Ono, Akira

2009-01-01

The relevance of equilibrium in a multifragmentation reaction of very central 40 Ca + 40 Ca collisions at 35 MeV/nucleon is investigated by using simulations of antisymmetrized molecular dynamics (AMD). Two types of ensembles are compared. One is the reaction ensemble of the states at each reaction time t in collision events simulated by AMD, and the other is the equilibrium ensemble prepared by solving the AMD equation of motion for a many-nucleon system confined in a container for a long time. The comparison of the ensembles is performed for the fragment charge distribution and the excitation energies. Our calculations show that there exists an equilibrium ensemble that well reproduces the reaction ensemble at each reaction time t for the investigated period 80≤t≤300 fm/c. However, there are some other observables that show discrepancies between the reaction and equilibrium ensembles. These may be interpreted as dynamical effects in the reaction. The usual static equilibrium at each instant is not realized since any equilibrium ensemble with the same volume as that of the reaction system cannot reproduce the fragment observables

Dynamic Data-Driven Reduced-Order Models of Macroscale Quantities for the Prediction of Equilibrium System State for Multiphase Porous Medium Systems

Science.gov (United States)

Talbot, C.; McClure, J. E.; Armstrong, R. T.; Mostaghimi, P.; Hu, Y.; Miller, C. T.

2017-12-01

Microscale simulation of multiphase flow in realistic, highly-resolved porous medium systems of a sufficient size to support macroscale evaluation is computationally demanding. Such approaches can, however, reveal the dynamic, steady, and equilibrium states of a system. We evaluate methods to utilize dynamic data to reduce the cost associated with modeling a steady or equilibrium state. We construct data-driven models using extensions to dynamic mode decomposition (DMD) and its connections to Koopman Operator Theory. DMD and its variants comprise a class of equation-free methods for dimensionality reduction of time-dependent nonlinear dynamical systems. DMD furnishes an explicit reduced representation of system states in terms of spatiotemporally varying modes with time-dependent oscillation frequencies and amplitudes. We use DMD to predict the steady and equilibrium macroscale state of a realistic two-fluid porous medium system imaged using micro-computed tomography (µCT) and simulated using the lattice Boltzmann method (LBM). We apply Koopman DMD to direct numerical simulation data resulting from simulations of multiphase fluid flow through a 1440x1440x4320 section of a full 1600x1600x5280 realization of imaged sandstone. We determine a representative set of system observables via dimensionality reduction techniques including linear and kernel principal component analysis. We demonstrate how this subset of macroscale quantities furnishes a representation of the time-evolution of the system in terms of dynamic modes, and discuss the selection of a subset of DMD modes yielding the optimal reduced model, as well as the time-dependence of the error in the predicted equilibrium value of each macroscale quantity. Finally, we describe how the above procedure, modified to incorporate methods from compressed sensing and random projection techniques, may be used in an online fashion to facilitate adaptive time-stepping and parsimonious storage of system states over time.

Numerical Verification Of Equilibrium Chemistry

International Nuclear Information System (INIS)

Piro, Markus; Lewis, Brent; Thompson, William T.; Simunovic, Srdjan; Besmann, Theodore M.

2010-01-01

A numerical tool is in an advanced state of development to compute the equilibrium compositions of phases and their proportions in multi-component systems of importance to the nuclear industry. The resulting software is being conceived for direct integration into large multi-physics fuel performance codes, particularly for providing boundary conditions in heat and mass transport modules. However, any numerical errors produced in equilibrium chemistry computations will be propagated in subsequent heat and mass transport calculations, thus falsely predicting nuclear fuel behaviour. The necessity for a reliable method to numerically verify chemical equilibrium computations is emphasized by the requirement to handle the very large number of elements necessary to capture the entire fission product inventory. A simple, reliable and comprehensive numerical verification method is presented which can be invoked by any equilibrium chemistry solver for quality assurance purposes.

Origins of microstructural transformations in charged vesicle suspensions: the crowding hypothesis.

Science.gov (United States)

Seth, Mansi; Ramachandran, Arun; Murch, Bruce P; Leal, L Gary

2014-09-02

It is observed that charged unilamellar vesicles in a suspension can spontaneously deflate and subsequently transition to form bilamellar vesicles, even in the absence of externally applied triggers such as salt or temperature gradients. We provide strong evidence that the driving force for this deflation-induced transition is the repulsive electrostatic pressure between charged vesicles in concentrated suspensions, above a critical effective volume fraction. We use volume fraction measurements and cryogenic transmission electron microscopy imaging to quantitatively follow both the macroscopic and microstructural time-evolution of cationic diC18:1 DEEDMAC vesicle suspensions at different surfactant and salt concentrations. A simple model is developed to estimate the extent of deflation of unilamellar vesicles caused by electrostatic interactions with neighboring vesicles. It is determined that when the effective volume fraction of the suspension exceeds a critical value, charged vesicles in a suspension can experience "crowding" due to overlap of their electrical double layers, which can result in deflation and subsequent microstructural transformations to reduce the effective volume fraction of the suspension. Ordinarily in polydisperse colloidal suspensions, particles interacting via a repulsive potential transform into a glassy state above a critical volume fraction. The behavior of charged vesicle suspensions reported in this paper thus represents a new mechanism for the relaxation of repulsive interactions in crowded situations.

Non-Equilibrium Properties from Equilibrium Free Energy Calculations

Science.gov (United States)

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.

Large-scale photochemical reactions of nanocrystalline suspensions: a promising green chemistry method.

Science.gov (United States)

Veerman, Marcel; Resendiz, Marino J E; Garcia-Garibay, Miguel A

2006-06-08

Photochemical reactions in the solid state can be scaled up from a few milligrams to 10 grams by using colloidal suspensions of a photoactive molecular crystal prepared by the solvent shift method. Pure products are recovered by filtration, and the use of H(2)O as a suspension medium makes this method a very attractive one from a green chemistry perspective. Using the photodecarbonylation of dicumyl ketone (DCK) as a test system, we show that reaction efficiencies in colloidal suspensions rival those observed in solution. [reaction: see text

Vibration control of an energy regenerative seat suspension with variable external resistance

Science.gov (United States)

Ning, Donghong; Sun, Shuaishuai; Du, Haiping; Li, Weihua; Zhang, Nong

2018-06-01

In this paper, an energy regenerative seat suspension with a variable external resistance is proposed and built, and a semi-active controller for its vibration control is also designed and validated. The energy regenerative seat suspension is built with a three-phase generator and a gear reducer, which are installed in the scissors structure centre of the seat suspension, and the vibration energy is directly harvested from the rotary movement of suspension's scissors structure. The electromagnetic torque of the semi-active seat suspension actuator is controlled by an external variable resistor. An integrated model including the seat suspension's kinematics and the generator is built and proven to match the test result very well. A simplified experimental phenomenon model is also built based on the test results for the controller design. A state feedback H∞ controller is proposed for the regenerative seat suspension's semi-active vibration control. The proposed regenerative seat suspension and its controller are validated with both simulations and experiments. A well-tuned passive seat suspension is applied to evaluate the regenerative seat's performance. Based on ISO 2631-1, the frequency-weighted root mean square (FW-RMS) acceleration of the proposed seat suspension has a 22.84% reduction when compared with the passive one, which indicates the improvement of ride comfort. At the same time, the generated RMS power is 1.21 W. The proposed regenerative seat suspension can greatly improve the driver's ride comfort and has the potential to be developed to a self-powered semi-active system.

Average equilibrium charge state of 278113 ions moving in a helium gas

International Nuclear Information System (INIS)

Kaji, D.; Morita, K.; Morimoto, K.

2005-01-01

Difficulty to identify a new heavy element comes from the small production cross section. For example, the production cross section was about 0.5 pb in the case of searching for the 112th element produced by the cold fusion reaction of 208 Pb( 70 Zn,n) 277 ll2. In order to identify heavier elements than element 112, the experimental apparatus with a sensitivity of sub-pico barn level is essentially needed. A gas-filled recoil separator, in general, has a large collection efficiency compared with other recoil separators as seen from the operation principle of a gas-filled recoil separator. One of the most important parameters for a gas-filled recoil separator is the average equilibrium charge state q ave of ions moving in a used gas. This is because the recoil ion can not be properly transported to the focal plane of the separator, if the q ave of an element of interest in a gas is unknown. We have systematically measured equilibrium charge state distributions of heavy ions ( 169 Tm, 208 Pb, 193,209 Bi, 196 Po, 200 At, 203,204 Fr, 212 Ac, 234 Bk, 245 Fm, 254 No, 255 Lr, and 265 Hs) moving in a helium gas by using the gas-filled recoil separator GARIS at RIKEN. Ana then, the empirical formula on q ave of heavy ions in a helium gas was derived as a function of the velocity and the atomic number of an ion on the basis of the Tomas-Fermi model of the atom. The formula was found to be applicable to search for transactinide nuclides of 271 Ds, 272 Rg, and 277 112 produced by cold fusion reactions. Using the formula on q ave , we searched for a new isotope of element 113 produced by the cold fusion reaction of 209 Bi( 70 Zn,n) 278 113. As a result, a decay chain due to an evaporation residue of 278 113 was observed. Recently, we have successfully observed the 2nd decay chain due to an evaporation residue of 278 113. In this report, we will present experimental results in detail, and will also discuss the average equilibrium charge sate of 278 113 in a helium gas by

Performance Testing of Suspension Plasma Sprayed Thermal Barrier Coatings Produced with Varied Suspension Parameters

Directory of Open Access Journals (Sweden)

Nicholas Curry

2015-07-01

Full Text Available Suspension plasma spraying has become an emerging technology for the production of thermal barrier coatings for the gas turbine industry. Presently, though commercial systems for coating production are available, coatings remain in the development stage. Suitable suspension parameters for coating production remain an outstanding question and the influence of suspension properties on the final coatings is not well known. For this study, a number of suspensions were produced with varied solid loadings, powder size distributions and solvents. Suspensions were sprayed onto superalloy substrates coated with high velocity air fuel (HVAF -sprayed bond coats. Plasma spray parameters were selected to generate columnar structures based on previous experiments and were maintained at constant to discover the influence of the suspension behavior on coating microstructures. Testing of the produced thermal barrier coating (TBC systems has included thermal cyclic fatigue testing and thermal conductivity analysis. Pore size distribution has been characterized by mercury infiltration porosimetry. Results show a strong influence of suspension viscosity and surface tension on the microstructure of the produced coatings.

Investigating high-concentration monoclonal antibody powder suspension in nonaqueous suspension vehicles for subcutaneous injection.

Science.gov (United States)

Bowen, Mayumi; Armstrong, Nick; Maa, Yuh-Fun

2012-12-01

Developing high-concentration monoclonal antibody (mAb) liquid formulations for subcutaneous (s.c.) administration is challenging because increased viscosity makes injection difficult. To overcome this obstacle, we investigated a nonaqueous powder suspension approach. Three IgG1 mAbs were spray dried and suspended at different concentrations in Miglyol® 840, benzyl benzoate, or ethyl lactate. Suspensions were characterized for viscosity, particle size, and syringeability; physical stability was visually inspected. Suspensions generally outperformed liquid solutions for injectability despite higher viscosity at the same mAb concentrations. Powder formulations and properties had little effect on viscosity or injectability. Ethyl lactate suspensions had lowest viscosity (Miglyol® 840 improved overall performance in high mAb concentration suspensions. This study demonstrated the viability of high mAb concentration (>300 mg/mL) in suspension formulations for s.c. administration. Copyright © 2012 Wiley Periodicals, Inc.

Four-Wheel Vehicle Suspension System

Science.gov (United States)

Bickler, Donald B.

1990-01-01

Four-wheel suspension system uses simple system of levers with no compliant components to provide three-point suspension of chassis of vehicle while maintaining four-point contact with uneven terrain. Provides stability against tipping of four-point rectangular base, without rocking contact to which rigid four-wheel frame susceptible. Similar to six-wheel suspension system described in "Articulated Suspension Without Springs" (NPO-17354).

Analysis of radioactive-matter interaction near thermodynamical equilibrium states

International Nuclear Information System (INIS)

Damamme, G.

1993-01-01

We study the absorption/emission process of photon by matter in the framework of a radiativo-collisionnal model of atom, a thermodynamical approach being used. The considered matter description is the atomic sphere one. First we give the expression of the balance equation around an equilibrium state. Then we express the atomic populations in function of the characteristics of the radiation and of the free electrons and of their time history. This permit us to interpret the photon balance as being due to true emission/absorption process of photons as well as fluorescence terms, all these processes being affected by relaxation effects. The total energy balance between matter and radiation can also be analyzed in the same way and conduct to introduce one photon effective interactions terms for each radiative proper mode, terms also affected by retardation effects. Such a taking into account of atom populations has no consequence on the radiative flux equation (i.e. the transfer opacity) but can considerably modify the energy balance between matter and radiation. (author). 11 refs., 3 figs

Suspension trauma; Le traumatisme de suspension

Energy Technology Data Exchange (ETDEWEB)

Trudel, S. [Le Centre de sante et de services sociaux du rocher Perce, Chandler, PQ (Canada)

2010-07-01

This presentation discussed the precautions that should be taken to avoid falls from wind turbines or transmission towers. Suspension trauma was explained by a medical doctor in terms of physiology and the body's normal circulation and the elements that disturb normal physiology when in suspension. The trauma occurs following a fall, which carries the risk of 1or more disorders, such as massive hemorrhage, high cardiac pulse, and constriction of blood vessels. Nausea, vertigo, cardiac arrhythmia and sweating occur 15 to 20 minutes following the fall. The presentation emphasized the importance of having qualified personnel at the site and wearing proper harnesses and equipment that supports the neck. figs.

Charge-changing processes of heavy ions in matter. Non-equilibrium charge state distribution of sulfur ions after carbon foil penetration

International Nuclear Information System (INIS)

Imai, Makoto; Shibata, Hiromi; Sataka, Masao; Sugai, Hiroyuki; Nishio, Katsuhisa; Sugiyama, Koji; Komaki, Ken-ichiro

2005-01-01

Charge state distributions of 2.0 MeV/u (64 MeV) sulfur ions of various initial charge states (6+, 10+, 11+, 13+) after passing through 0.9, 1.1, 1.5, 2.0, 3.0, 4.7, 6.9 and 10 μg/cm 2 carbon foils have been studied experimentally using the heavy ion spectrometer 'ENMA'. Measured charge state distributions do not flat off to establish equilibrium within the measured thickness, proving to be the first systematic measurement of non-equilibrium charge state distribution using solid target at this energy range. The mean charge states and their distribution widths almost saturate to 12.4 and 1.03, respectively, for all initial charge states examined. Calculation with ETACHA code, developed by Rozet et al. [Nucl. Instr. and Meth. B 107 (1996) 67], is employed, although the present impact energy is lower than the assumed energy region for this code. It was also confirmed that a certain portion of 16 O q+ (q=3, 4, 7) beam is included in 32 S q+ (q=6, 8, 14) beam provided from the Tandem Accelerator, which originates in the Negative Ion Source forming O 2 - . (author)

Adaptive magnetorheological seat suspension for the expeditionary fighting vehicle

International Nuclear Information System (INIS)

Hiemenz, G J; Hu, W; Wereley, N M

2009-01-01

The Expeditionary Fighting Vehicle (EFV) is an amphibious vehicle designed to operate through harsh conditions and at much higher speeds than its predecessors. These unique capabilities and broadly varying operational conditions lead to a complex design and human factors scenario for the forward seating positions that cannot be solved using conventional passive seat suspension systems. Injurious shock loads transmitted to the occupants when traversing over water in high sea states and/or at high speeds, as well as harmful shock and vibration transmitted to the occupants when the vehicle is travelling over land, pose a threat to occupant health and significantly limit mission duration. In this study, a semi-active magnetorheological (MR) seat suspension is developed which adapts to broadly varying operational conditions, as well as occupant weight, to provide optimal protection of EFV occupants. It is shown that this MR seat suspension system will reduce the shock and vibration transmitted to the occupant by up to 33% and 65%, respectively, as compared to the existing passive suspension.

Adaptive magnetorheological seat suspension for the expeditionary fighting vehicle

Energy Technology Data Exchange (ETDEWEB)

Hiemenz, G J [Techno-Sciences, Inc., 11750 Beltsville Dr. Ste. 300, Beltsville, MD 20705 (United States); Hu, W; Wereley, N M [Aerospace Engineering, University of Maryland, College Park, MD 20712 (United States)], E-mail: greg@technosci.com, E-mail: wereley@umd.edu

2009-02-01

The Expeditionary Fighting Vehicle (EFV) is an amphibious vehicle designed to operate through harsh conditions and at much higher speeds than its predecessors. These unique capabilities and broadly varying operational conditions lead to a complex design and human factors scenario for the forward seating positions that cannot be solved using conventional passive seat suspension systems. Injurious shock loads transmitted to the occupants when traversing over water in high sea states and/or at high speeds, as well as harmful shock and vibration transmitted to the occupants when the vehicle is travelling over land, pose a threat to occupant health and significantly limit mission duration. In this study, a semi-active magnetorheological (MR) seat suspension is developed which adapts to broadly varying operational conditions, as well as occupant weight, to provide optimal protection of EFV occupants. It is shown that this MR seat suspension system will reduce the shock and vibration transmitted to the occupant by up to 33% and 65%, respectively, as compared to the existing passive suspension.

Equilibrium Constant as Solution to the Open Chemical Systems

OpenAIRE

Zilbergleyt, B.

2008-01-01

According to contemporary views, equilibrium constant is relevant only to true thermodynamic equilibria in isolated systems with one chemical reaction. The paper presents a novel formula that ties-up equilibrium constant and chemical system composition at any state, isolated or open as well. Extending the logarithmic logistic map of the Discrete Thermodynamics of Chemical Equilibria, this formula maps the system population at isolated equilibrium into the population at any open equilibrium at...

Thermodynamic theory of equilibrium fluctuations

International Nuclear Information System (INIS)

Mishin, Y.

2015-01-01

The postulational basis of classical thermodynamics has been expanded to incorporate equilibrium fluctuations. The main additional elements of the proposed thermodynamic theory are the concept of quasi-equilibrium states, a definition of non-equilibrium entropy, a fundamental equation of state in the entropy representation, and a fluctuation postulate describing the probability distribution of macroscopic parameters of an isolated system. Although these elements introduce a statistical component that does not exist in classical thermodynamics, the logical structure of the theory is different from that of statistical mechanics and represents an expanded version of thermodynamics. Based on this theory, we present a regular procedure for calculations of equilibrium fluctuations of extensive parameters, intensive parameters and densities in systems with any number of fluctuating parameters. The proposed fluctuation formalism is demonstrated by four applications: (1) derivation of the complete set of fluctuation relations for a simple fluid in three different ensembles; (2) fluctuations in finite-reservoir systems interpolating between the canonical and micro-canonical ensembles; (3) derivation of fluctuation relations for excess properties of grain boundaries in binary solid solutions, and (4) derivation of the grain boundary width distribution for pre-melted grain boundaries in alloys. The last two applications offer an efficient fluctuation-based approach to calculations of interface excess properties and extraction of the disjoining potential in pre-melted grain boundaries. Possible future extensions of the theory are outlined.

Force-dominated non-equilibrium oxidation kinetics of tantalum

International Nuclear Information System (INIS)

Kar, Prasenjit; Wang, Ke; Liang, Hong

2008-01-01

Using a combined electrochemical and mechanical manipulation technique, we compared the equilibrium and non-equilibrium oxidation processes and states of tantalum. Experimentally, a setup was developed with an electrochemical system attached to a sliding mechanical configuration capable of friction force measurement. The surface chemistry of a sliding surface, i.e., tantalum, was modified through the electrolyte. The mechanically applied force was fixed and the dynamics of the surface was monitored in situ through a force sensor. The formation of non-equilibrium oxidation states of tantalum was found in oxidation limiting environment of acetic acid. An oxidative environment of deionized water saturated with KCl was used as comparison. We proposed a modified Arrhenius-Eyring equation in which the mechanical factor was considered. We found that the mechanical energy induced the non-stable-state reactions leading to metastable oxidation states of tantalum. This equation can be used to predict mechanochemical reactions that are important in many industrial applications

Influence of vibration on structure rheological properties of a highly concentrated suspension

Science.gov (United States)

Ouriev Uriev, Boris N.; Uriev, Naum B.

2005-08-01

The influence of mechanical vibration on the flow properties of a highly concentrated multiphase food system is explored in this work. An experimental set-up was designed and adapted to a conventional rotational rheometer with precise rheological characterization capability. A number of calibration tests were performed prior to fundamental experiments with a highly concentrated chocolate suspension. Also, the prediction of wall slippage in shear flow under vibration was evaluated. Analysis of the boundary conditions shows that no side effects such as wall slippage or the Taylor effect were present during the shear experiment under vibration. It was found that superposition of mechanical vibration and shear flow radically decreases the shear viscosity. Comparison between reference shear viscosities at specified shear rates and those measured under vibration shows considerable differences in flow properties. Conversion of the behaviour of the concentrated suspension from strongly shear-thinning to Newtonian flow is reported. Also, the appearance of vibration-induced dilatancy as a new phenomenon is described. It is suggested to relate such phenomena to the non-equilibrium between structure formation and disintegration under vibration and hydrodynamic forces of shear flow. The influence of vibration on structure formation can be well observed during measurement of the yield value of the chocolate suspension under vibration. Comparison with reference data shows how sensitive the structure of the concentrated suspension is to vibration in general. The effects and observations revealed provide a solid basis for further fundamental investigations of structure formation regularities in the flow of any highly concentrated system. The results also show the technological potential for non-conventional treatment of concentrated, multiphase systems.

Three-body correlations and conditional forces in suspensions of active hard disks

Science.gov (United States)

Härtel, Andreas; Richard, David; Speck, Thomas

2018-01-01

Self-propelled Brownian particles show rich out-of-equilibrium physics, for instance, the motility-induced phase separation (MIPS). While decades of studying the structure of liquids have established a deep understanding of passive systems, not much is known about correlations in active suspensions. In this work we derive an approximate analytic theory for three-body correlations and forces in systems of active Brownian disks starting from the many-body Smoluchowski equation. We use our theory to predict the conditional forces that act on a tagged particle and their dependence on the propulsion speed of self-propelled disks. We identify preferred directions of these forces in relation to the direction of propulsion and the positions of the surrounding particles. We further relate our theory to the effective swimming speed of the active disks, which is relevant for the physics of MIPS. To test and validate our theory, we additionally run particle-resolved computer simulations, for which we explicitly calculate the three-body forces. In this context, we discuss the modeling of active Brownian swimmers with nearly hard interaction potentials. We find very good agreement between our simulations and numerical solutions of our theory, especially for the nonequilibrium pair-distribution function. For our analytical results, we carefully discuss their range of validity in the context of the different levels of approximation we applied. This discussion allows us to study the individual contribution of particles to three-body forces and to the emerging structure. Thus, our work sheds light on the collective behavior, provides the basis for further studies of correlations in active suspensions, and makes a step towards an emerging liquid state theory.

9 CFR 161.4 - Suspension or revocation of veterinary accreditation; criminal and civil penalties.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Suspension or revocation of veterinary... REVOCATION OF SUCH ACCREDITATION § 161.4 Suspension or revocation of veterinary accreditation; criminal and... to practice veterinary medicine in at least one State. (c) Accreditation shall be automatically...

BINARY NEUTRON STARS IN QUASI-EQUILIBRIUM

International Nuclear Information System (INIS)

Taniguchi, Keisuke; Shibata, Masaru

2010-01-01

Quasi-equilibrium sequences of binary neutron stars are constructed for a variety of equations of state in general relativity. Einstein's constraint equations in the Isenberg-Wilson-Mathews approximation are solved together with the relativistic equations of hydrostationary equilibrium under the assumption of irrotational flow. We focus on unequal-mass sequences as well as equal-mass sequences, and compare those results. We investigate the behavior of the binding energy and total angular momentum along a quasi-equilibrium sequence, the endpoint of sequences, and the orbital angular velocity as a function of time, changing the mass ratio, the total mass of the binary system, and the equation of state of a neutron star. It is found that the orbital angular velocity at the mass-shedding limit can be determined by an empirical formula derived from an analytic estimation. We also provide tables for 160 sequences, which will be useful as a guideline of numerical simulations for the inspiral and merger performed in the near future.

Stochastic thermodynamics of quantum maps with and without equilibrium.

Science.gov (United States)

Barra, Felipe; Lledó, Cristóbal

2017-11-01

We study stochastic thermodynamics for a quantum system of interest whose dynamics is described by a completely positive trace-preserving (CPTP) map as a result of its interaction with a thermal bath. We define CPTP maps with equilibrium as CPTP maps with an invariant state such that the entropy production due to the action of the map on the invariant state vanishes. Thermal maps are a subgroup of CPTP maps with equilibrium. In general, for CPTP maps, the thermodynamic quantities, such as the entropy production or work performed on the system, depend on the combined state of the system plus its environment. We show that these quantities can be written in terms of system properties for maps with equilibrium. The relations that we obtain are valid for arbitrary coupling strengths between the system and the thermal bath. The fluctuations of thermodynamic quantities are considered in the framework of a two-point measurement scheme. We derive the entropy production fluctuation theorem for general maps and a fluctuation relation for the stochastic work on a system that starts in the Gibbs state. Some simplifications for the probability distributions in the case of maps with equilibrium are presented. We illustrate our results by considering spin 1/2 systems under thermal maps, nonthermal maps with equilibrium, maps with nonequilibrium steady states, and concatenations of them. Finally, and as an important application, we consider a particular limit in which the concatenation of maps generates a continuous time evolution in Lindblad form for the system of interest, and we show that the concept of maps with and without equilibrium translates into Lindblad equations with and without quantum detailed balance, respectively. The consequences for the thermodynamic quantities in this limit are discussed.

A philosophy of rivers: Equilibrium states, channel evolution, teleomatic change and least action principle

Science.gov (United States)

Nanson, Gerald C.; Huang, He Qing

2018-02-01

Until recently no universal agreement as to a philosophical or scientific methodological framework has been proposed to guide the study of fluvial geomorphology. An understanding of river form and process requires an understanding of the principles that govern the behaviour and evolution of alluvial rivers at the most fundamental level. To date, the investigations of such principles have followed four approaches: develop qualitative unifying theories that are usually untested; collect and examine data visually and statistically to define semi-quantitative relationships among variables; apply Newtonian theoretical and empirical mechanics in a reductionist manner; resolve the primary flow equations theoretically by assuming maximum or minimum outputs. Here we recommend not a fifth but an overarching philosophy to embrace all four: clarifying and formalising an understanding of the evolution of river channels and iterative directional changes in the context of least action principle (LAP), the theoretical basis of variational mechanics. LAP is exemplified in rivers in the form of maximum flow efficiency (MFE). A sophisticated understanding of evolution in its broadest sense is essential to understand how rivers adjust towards an optimum state rather than towards some other. Because rivers, as dynamic contemporary systems, flow in valleys that are commonly historical landforms and often tectonically determined, we propose that most of the world's alluvial rivers are over-powered for the work they must do. To remain stable they commonly evolve to expend surplus energy via a variety of dynamic equilibrium forms that will further adjust, where possible, to maximise their stability as much less common MFE forms in stationary equilibrium. This paper: 1. Shows that the theory of evolution is derived from, and applicable to, both the physical and biological sciences; 2. Focusses the development of theory in geomorphology on the development of equilibrium theory; 3. Proposes

Non-equilibrium spectroscopy of high-Tc superconductors

International Nuclear Information System (INIS)

Krasnov, V M

2009-01-01

In superconductors, recombination of two non-equilibrium quasiparticles into a Cooper pair results in emission of excitation that mediates superconductivity. This is the basis of the proposed new type of 'non-equilibrium' spectroscopy of high T c superconductors, which may open a possibility for direct and unambiguous determination of the coupling mechanism of high T c superconductivity. In case of low T c superconductors, the feasibility of such the non-equilibrium spectroscopy was demonstrated in classical phonon generation-detection experiments almost four decades ago. Recently it was demonstrated that a similar technique can be used for high T c superconductors, using natural intrinsic Josephson junctions both for injection of non-equilibrium quasiparticles and for detection of the non-equilibrium radiation. Here I analyze theoretically non-equilibrium phenomena in intrinsic Josephson junctions. It is shown that extreme non-equilibrium state can be achieved at bias equal to integer number of the gap voltage, which can lead to laser-like emission from the stack. I argue that identification of the boson type, constituting this non-equilibrium radiation would unambiguously reveal the coupling mechanism of high Tc superconductors.

Fluctuation relations in non-equilibrium stationary states of Ising models

Energy Technology Data Exchange (ETDEWEB)

Piscitelli, A; Gonnella, G [Dipartimento di Fisica, Universita di Bari and Istituto Nazionale di Fisica Nucleare, Sezione di Bari, via Amendola 173, 70126 Bari (Italy); Corberi, F [Dipartimento di Matematica ed Informatica, via Ponte don Melillo, Universita di Salerno, 84084 Fisciano (Italy); Pelizzola, A [Dipartimento di Fisica and Istituto Nazionale di Fisica Nucleare, Sezione di Torino, and CNISM, Politecnico di Torino, c. Duca degli Abruzzi 24, 10129 Torino (Italy)

2009-01-15

Fluctuation relations for the entropy production in non-equilibrium stationary states of Ising models are investigated by means of Monte Carlo simulations. Systems in contact with heat baths at two different temperatures or subject to external driving will be studied. In the first case, considering different kinetic rules and couplings with the baths, the behaviors of the probability distributions of the heat exchanged in time {tau} with the thermostats, both in the disordered phase and in the low temperature phase, are discussed. The fluctuation relation is always followed in the large {tau} limit and deviations from linear response theory are observed. Finite {tau} corrections are shown to obey a scaling behavior. In the other case the system is in contact with a single heat bath, but work is done by shearing it. Also for this system, using the statistics collected for the mechanical work we show the validity of the fluctuation relation and the preasymptotic corrections behave analogously to those for the case with two baths.

Design of a suspension system and determining suspension parameters of a medium downforce small Formula type car

Directory of Open Access Journals (Sweden)

Biswal Sadjyot

2017-01-01

Full Text Available The focus of the paper is on designing a suspension system for a medium downforce small Formula type race car. The paper not only focusses on step by step design for a double wishbone type suspension but will also show the use and role of kinematics software in determining the optimized suspension of the car. The paper will also focus on the use of tire data in determining suspension parameters and the design of the double wishbone suspension. Various parameters, their design importance and the process to optimize them according to suspension design goals will be covered. The easiest and best ways to change the suspension parameters to get the best results will also be covered.

Kinetic study of adsorption and degradation of aniline, benzoic acid, phenol, and diuron in soil suspensions

International Nuclear Information System (INIS)

Dao, T.H.; Lavy, T.L.

1987-01-01

Laboratory studies were conducted to investigate the effects of low temperature and accelerated soil-solution contact on soil adsorption of labile organic chemicals. The authors measured the kinetics of adsorption and degradation of 14 C-aniline, 14 C-benzoic acid, 14 C-phenol, and 14 C-diuron in the solution phase at 3 and 22 0 C. In the initial stages of reactions, the adsorption of all four chemicals was instantaneous at both temperatures under accelerated soil and solution mixing. A steady state was observed after the onset of equilibrium for the adsorption reaction for all compounds within 10 to 30 min. Its length varied according to the expected order of susceptibility to microbial degradation, i.e., diuron > aniline > phenol ≥ benzoate. It was apparent that the steady-state period without or in combination with low temperature could be advantageously used to obtain adsorption measurements in microbially active systems. A mechanistic sorption-catalyzed degradation model was evaluated to uncouple mathematically these processes. The model described satisfactorily the disappearance of labile chemicals in soil suspensions. Numerical analysis allowed the concurrent determination of adsorption, desorption, and biodegradation rate coefficients

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

MHD equilibrium identification on ASDEX-Upgrade

International Nuclear Information System (INIS)

McCarthy, P.J.; Schneider, W.; Lakner, K.; Zehrfeld, H.P.; Buechl, K.; Gernhardt, J.; Gruber, O.; Kallenbach, A.; Lieder, G.; Wunderlich, R.

1992-01-01

A central activity accompanying the ASDEX-Upgrade experiment is the analysis of MHD equilibria. There are two different numerical methods available, both using magnetic measurements which reflect equilibrium states of the plasma. The first method proceeds via a function parameterization (FP) technique, which uses in-vessel magnetic measurements to calculate up to 66 equilibrium parameters. The second method applies an interpretative equilibrium code (DIVA) for a best fit to a different set of magnetic measurements. Cross-checks with the measured particle influxes from the inner heat shield and the divertor region and with visible camera images of the scrape-off layer are made. (author) 3 refs., 3 figs

Poisson-Boltzmann theory of charged colloids: limits of the cell model for salty suspensions

International Nuclear Information System (INIS)

Denton, A R

2010-01-01

Thermodynamic properties of charge-stabilized colloidal suspensions and polyelectrolyte solutions are commonly modelled by implementing the mean-field Poisson-Boltzmann (PB) theory within a cell model. This approach models a bulk system by a single macroion, together with counterions and salt ions, confined to a symmetrically shaped, electroneutral cell. While easing numerical solution of the nonlinear PB equation, the cell model neglects microion-induced interactions and correlations between macroions, precluding modelling of macroion ordering phenomena. An alternative approach, which avoids the artificial constraints of cell geometry, exploits the mapping of a macroion-microion mixture onto a one-component model of pseudo-macroions governed by effective interparticle interactions. In practice, effective-interaction models are usually based on linear-screening approximations, which can accurately describe strong nonlinear screening only by incorporating an effective (renormalized) macroion charge. Combining charge renormalization and linearized PB theories, in both the cell model and an effective-interaction (cell-free) model, we compute osmotic pressures of highly charged colloids and monovalent microions, in Donnan equilibrium with a salt reservoir, over a range of concentrations. By comparing predictions with primitive model simulation data for salt-free suspensions, and with predictions from nonlinear PB theory for salty suspensions, we chart the limits of both the cell model and linear-screening approximations in modelling bulk thermodynamic properties. Up to moderately strong electrostatic couplings, the cell model proves accurate for predicting osmotic pressures of deionized (counterion-dominated) suspensions. With increasing salt concentration, however, the relative contribution of macroion interactions to the osmotic pressure grows, leading predictions from the cell and effective-interaction models to deviate. No evidence is found for a liquid

Estimation of radon progeny equilibrium factors and their uncertainty bounds using solid state nuclear track detectors

International Nuclear Information System (INIS)

Eappen, K.P.; Mayya, Y.S.; Patnaik, R.L.; Kushwaha, H.S.

2006-01-01

For the assessment of inhalation doses due to radon and its progeny to uranium mine workers, it is necessary to have information on the time integrated gas concentrations and equilibrium factors. Passive single cup dosimeters using solid state nuclear track detectors (SSNTD) are best suited for this purpose. These generally contain two SSNTDs, one placed inside the cup to measure only the radon gas concentration and other outside the cup for recording tracks due to both radon gas and the progeny species. However, since one obtains only two numbers by this method whereas information on four quantities is required for an unambiguous estimation of dose, there is a need for developing an optimal methodology for extracting information on the equilibrium factors. Several techniques proposed earlier have essentially been based on deterministic approaches, which do not fully take into account all the possible uncertainties in the environmental parameters. Keeping this in view, a simple 'mean of bounds' methodology is proposed to extract equilibrium factors based on their absolute bounds and the associated uncertainties as obtained from general arguments of radon progeny disequilibrium. This may be considered as reasonable estimates of the equilibrium factors in the absence of a knowledge of fluctuation in the environmental variables. The results are compared with those from direct measurements both in the laboratory and in real field situations. In view of the good agreement found between these, it is proposed that the simple mean of bounds estimate may be useful for practical applications in inhalation dosimetry of mine workers

The Rate-Controlled Constrained-Equilibrium Approach to Far-From-Local-Equilibrium Thermodynamics

Directory of Open Access Journals (Sweden)

Hameed Metghalchi

2012-01-01

Full Text Available The Rate-Controlled Constrained-Equilibrium (RCCE method for the description of the time-dependent behavior of dynamical systems in non-equilibrium states is a general, effective, physically based method for model order reduction that was originally developed in the framework of thermodynamics and chemical kinetics. A generalized mathematical formulation is presented here that allows including nonlinear constraints in non-local equilibrium systems characterized by the existence of a non-increasing Lyapunov functional under the system’s internal dynamics. The generalized formulation of RCCE enables to clarify the essentials of the method and the built-in general feature of thermodynamic consistency in the chemical kinetics context. In this paper, we work out the details of the method in a generalized mathematical-physics framework, but for definiteness we detail its well-known implementation in the traditional chemical kinetics framework. We detail proofs and spell out explicit functional dependences so as to bring out and clarify each underlying assumption of the method. In the standard context of chemical kinetics of ideal gas mixtures, we discuss the relations between the validity of the detailed balance condition off-equilibrium and the thermodynamic consistency of the method. We also discuss two examples of RCCE gas-phase combustion calculations to emphasize the constraint-dependent performance of the RCCE method.

Circulation du sang dans des architectures microfluidiques : comportements collectifs de particules déformables en écoulement confiné

OpenAIRE

Shen , Zaiyi

2016-01-01

Dynamics and rheology of a 2D confined suspension of vesicles (a model for RBCs) is studied numerically by using an immersed boundary lattice Boltzmann method (IB-LBM). We pay a special attention to the link between the spatiotemporal organization of the suspension and rheology. We first analyze situations in which vesicles perform tank-treading. The pair of vesicles settles into an equilibrium state with constant relative distance, which is regulated by the confinement. The equilibrium dista...

Non-Equilibrium Turbulence and Two-Equation Modeling

Science.gov (United States)

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.

Equilibrium Droplets on Deformable Substrates: Equilibrium Conditions.

Science.gov (United States)

Koursari, Nektaria; Ahmed, Gulraiz; Starov, Victor M

2018-05-15

Equilibrium conditions of droplets on deformable substrates are investigated, and it is proven using Jacobi's sufficient condition that the obtained solutions really provide equilibrium profiles of both the droplet and the deformed support. At the equilibrium, the excess free energy of the system should have a minimum value, which means that both necessary and sufficient conditions of the minimum should be fulfilled. Only in this case, the obtained profiles provide the minimum of the excess free energy. The necessary condition of the equilibrium means that the first variation of the excess free energy should vanish, and the second variation should be positive. Unfortunately, the mentioned two conditions are not the proof that the obtained profiles correspond to the minimum of the excess free energy and they could not be. It is necessary to check whether the sufficient condition of the equilibrium (Jacobi's condition) is satisfied. To the best of our knowledge Jacobi's condition has never been verified for any already published equilibrium profiles of both the droplet and the deformable substrate. A simple model of the equilibrium droplet on the deformable substrate is considered, and it is shown that the deduced profiles of the equilibrium droplet and deformable substrate satisfy the Jacobi's condition, that is, really provide the minimum to the excess free energy of the system. To simplify calculations, a simplified linear disjoining/conjoining pressure isotherm is adopted for the calculations. It is shown that both necessary and sufficient conditions for equilibrium are satisfied. For the first time, validity of the Jacobi's condition is verified. The latter proves that the developed model really provides (i) the minimum of the excess free energy of the system droplet/deformable substrate and (ii) equilibrium profiles of both the droplet and the deformable substrate.

Simplification of reversible Markov chains by removal of states with low equilibrium occupancy.

Science.gov (United States)

Ullah, Ghanim; Bruno, William J; Pearson, John E

2012-10-21

We present a practical method for simplifying Markov chains on a potentially large state space when detailed balance holds. A simple and transparent technique is introduced to remove states with low equilibrium occupancy. The resulting system has fewer parameters. The resulting effective rates between the remaining nodes give dynamics identical to the original system's except on very fast timescales. This procedure amounts to using separation of timescales to neglect small capacitance nodes in a network of resistors and capacitors. We illustrate the technique by simplifying various reaction networks, including transforming an acyclic four-node network to a three-node cyclic network. For a reaction step in which a ligand binds, the law of mass action implies a forward rate proportional to ligand concentration. The effective rates in the simplified network are found to be rational functions of ligand concentration. Copyright © 2012 Elsevier Ltd. All rights reserved.

Combining the GW formalism with the polarizable continuum model: A state-specific non-equilibrium approach

Energy Technology Data Exchange (ETDEWEB)

Duchemin, Ivan, E-mail: ivan.duchemin@cea.fr [INAC, SP2M/L-Sim, CEA/UJF Cedex 09, 38054 Grenoble (France); Jacquemin, Denis [Laboratoire CEISAM - UMR CNR 6230, Université de Nantes, 2 Rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3 (France); Institut Universitaire de France, 1 rue Descartes, 75005 Paris Cedex 5 (France); Blase, Xavier [CNRS, Inst. NÉEL, F-38000 Grenoble (France); Univ. Grenoble Alpes, Inst. NÉEL, F-38000 Grenoble (France)

2016-04-28

We have implemented the polarizable continuum model within the framework of the many-body Green’s function GW formalism for the calculation of electron addition and removal energies in solution. The present formalism includes both ground-state and non-equilibrium polarization effects. In addition, the polarization energies are state-specific, allowing to obtain the bath-induced renormalisation energy of all occupied and virtual energy levels. Our implementation is validated by comparisons with ΔSCF calculations performed at both the density functional theory and coupled-cluster single and double levels for solvated nucleobases. The present study opens the way to GW and Bethe-Salpeter calculations in disordered condensed phases of interest in organic optoelectronics, wet chemistry, and biology.

Sintering of Fine Particles in Suspension Plasma Sprayed Coatings

Directory of Open Access Journals (Sweden)

Leszek Latka

2010-07-01

Full Text Available Suspension plasma spraying is a process that enables the production of finely grained nanometric or submicrometric coatings. The suspensions are formulated with the use of fine powder particles in water or alcohol with some additives. Subsequently, the suspension is injected into plasma jet and the liquid additives evaporate. The remaining fine solids are molten and subsequently agglomerate or remain solid, depending on their trajectory in the plasma jet. The coating’s microstructure results from these two groups of particles arriving on a substrate or previously deposited coating. Previous experimental studies carried out for plasma sprayed titanium oxide and hydroxyapatite coatings enabled us to observe either a finely grained microstructure or, when a different suspension injection mode was used, to distinguish two zones in the microstructure. These two zones correspond to the dense zone formed from well molten particles, and the agglomerated zone formed from fine solid particles that arrive on the substrate in a solid state. The present paper focuses on the experimental and theoretical analysis of the formation process of the agglomerated zone. The experimental section establishes the heat flux supplied to the coating during deposition. In order to achieve this, calorimetric measurements were made by applying experimental conditions simulating the real coatings’ growth. The heat flux was measured to be in the range from 0.08 to 0.5 MW/m2,depending on the experimental conditions. The theoretical section analyzes the sintering during the coating’s growth, which concerns the fine particles arriving on the substrate in the solid state. The models of volume, grain boundary and surface diffusion were analyzed and adapted to the size and chemistry of the grains, temperature and time scales corresponding to the suspension plasma spraying conditions. The model of surface diffusion was found to best describe the sintering during suspension

Heterogeneity of equilibrium molten globule state of cytochrome c induced by weak salt denaturants under physiological condition.

Directory of Open Access Journals (Sweden)

Hamidur Rahaman

Full Text Available While many proteins are recognized to undergo folding via intermediate(s, the heterogeneity of equilibrium folding intermediate(s along the folding pathway is less understood. In our present study, FTIR spectroscopy, far- and near-UV circular dichroism (CD, ANS and tryptophan fluorescence, near IR absorbance spectroscopy and dynamic light scattering (DLS were used to study the structural and thermodynamic characteristics of the native (N, denatured (D and intermediate state (X of goat cytochorme c (cyt-c induced by weak salt denaturants (LiBr, LiCl and LiClO4 at pH 6.0 and 25°C. The LiBr-induced denaturation of cyt-c measured by Soret absorption (Δε400 and CD ([θ]409, is a three-step process, N ↔ X ↔ D. It is observed that the X state obtained along the denaturation pathway of cyt-c possesses common structural and thermodynamic characteristics of the molten globule (MG state. The MG state of cyt-c induced by LiBr is compared for its structural and thermodynamic parameters with those found in other solvent conditions such as LiCl, LiClO4 and acidic pH. Our observations suggest: (1 that the LiBr-induced MG state of cyt-c retains the native Met80-Fe(III axial bond and Trp59-propionate interactions; (2 that LiBr-induced MG state of cyt-c is more compact retaining the hydrophobic interactions in comparison to the MG states induced by LiCl, LiClO4 and 0.5 M NaCl at pH 2.0; and (3 that there exists heterogeneity of equilibrium intermediates along the unfolding pathway of cyt-c as highly ordered (X1, classical (X2 and disordered (X3, i.e., D ↔ X3 ↔ X2 ↔ X1 ↔ N.

The molecular aggregation of pyronin Y in natural bentonite clay suspension

International Nuclear Information System (INIS)

Meral, Kadem; Yilmaz, Nuray; Kaya, Mehmet; Tabak, Ahmet; Onganer, Yavuz

2011-01-01

The molecular aggregation and spectroscopic properties of Pyronin Y (PyY) in the suspension containing natural bentonite clay were studied using molecular absorption, steady-state and time-resolved fluorescence spectroscopy techniques. Interaction between the clay particles and the cationic dye compounds in aqueous solution resulted in significant changes in spectral properties of PyY compared to its molecular behavior in deionized water at the same concentration. These changes were due to the formation of dimer and aggregate of PyY in the clay suspension as well as the presence of the dye monomer. The H-type aggregates of PyY in the clay suspension were identified by the observation of a blue-shifted absorption band of the dye compared to that of its monomer. In spite of diluted dye concentrations, the H-aggregate of PyY in the clay suspension was formed. The intensive aggregation in the clay suspension attributed to the localized high dye concentration on the negatively charged clay surfaces. Adsorption sites of PyY on the clay particles were discussed by deconvulated absorption and excitation spectra. Fluorescence spectroscopy studies revealed that the fluorescence intensity of PyY in the clay suspension is decreased by H-aggregates drastically. Moreover, the presence of H-aggregates in the clay suspension resulted in the decrease of fluorescence lifetime and quantum yield of PyY compared to those in deionized water. - Highlights: → Molecular behavior of PyY adsorbed on clay surface was followed spectroscopically. → H-aggregates of PyY in the clay suspension were formed at very low dye concentrations. → The intensive H-aggregate structure drastically reduced the fluorescence intensity of PyY. → The fluorescence lifetime and quantum yield of PyY in the clay suspension was discussed.

Brownian Dynamics of a Suspension of Particles with Constrained Voronoi Cell Volumes

KAUST Repository

Singh, John P.; Walsh, Stuart D. C.; Koch, Donald L.

2015-01-01

© 2015 American Chemical Society. Solvent-free polymer-grafted nanoparticle fluids consist of inorganic core particles fluidized by polymers tethered to their surfaces. The attachment of the suspending fluid to the particle surface creates a strong penalty for local variations in the fluid volume surrounding the particles. As a model of such a suspension we perform Brownian dynamics of an equilibrium system consisting of hard spheres which experience a many-particle potential proportional to the variance of the Voronoi volumes surrounding each particle (E = α(Vi-V0)²). The coefficient of proportionality α can be varied such that pure hard sphere dynamics is recovered as α → 0, while an incompressible array of hairy particles is obtained as α →. As α is increased the distribution of Voronoi volumes becomes narrower, the mean coordination number of the particle increases and the variance in the number of nearest neighbors decreases. The nearest neighbor peaks in the pair distribution function are suppressed and shifted to larger radial separations as the constraint acts to maintain relatively uniform interstitial regions. The structure factor of the model suspension satisfies S(k=0) → 0 as α → in accordance with expectation for a single component (particle plus tethered fluid) incompressible system. The tracer diffusivity of the particles is reduced by the volume constraint and goes to zero at φ 0.52, indicating an earlier glass transition than has been observed in hard sphere suspensions. The total pressure of the suspension grows in proportion to (αkBT)^1/2 as the strength of the volume-constraint potential grows. This stress arises primarily from the interparticle potential forces, while the hard-sphere collisional contribution to the stress is suppressed by the volume constraint.

Brownian Dynamics of a Suspension of Particles with Constrained Voronoi Cell Volumes

KAUST Repository

Singh, John P.

2015-06-23

© 2015 American Chemical Society. Solvent-free polymer-grafted nanoparticle fluids consist of inorganic core particles fluidized by polymers tethered to their surfaces. The attachment of the suspending fluid to the particle surface creates a strong penalty for local variations in the fluid volume surrounding the particles. As a model of such a suspension we perform Brownian dynamics of an equilibrium system consisting of hard spheres which experience a many-particle potential proportional to the variance of the Voronoi volumes surrounding each particle (E = α(Vi-V0)²). The coefficient of proportionality α can be varied such that pure hard sphere dynamics is recovered as α → 0, while an incompressible array of hairy particles is obtained as α →. As α is increased the distribution of Voronoi volumes becomes narrower, the mean coordination number of the particle increases and the variance in the number of nearest neighbors decreases. The nearest neighbor peaks in the pair distribution function are suppressed and shifted to larger radial separations as the constraint acts to maintain relatively uniform interstitial regions. The structure factor of the model suspension satisfies S(k=0) → 0 as α → in accordance with expectation for a single component (particle plus tethered fluid) incompressible system. The tracer diffusivity of the particles is reduced by the volume constraint and goes to zero at φ 0.52, indicating an earlier glass transition than has been observed in hard sphere suspensions. The total pressure of the suspension grows in proportion to (αkBT)^1/2 as the strength of the volume-constraint potential grows. This stress arises primarily from the interparticle potential forces, while the hard-sphere collisional contribution to the stress is suppressed by the volume constraint.

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

Quasi-equilibrium interpretation of aging dynamics

International Nuclear Information System (INIS)

Franz, S.; Virasoro, M.A.

2000-04-01

We develop an interpretation of the off-equilibrium dynamical solution of mean-field glassy models in terms of quasi-equilibrium concepts. We show that the relaxation of the 'thermoremanent magnetization' follows a generalized version of the Onsager regression postulate of induced fluctuations. We then find the rationale for the equality between the fluctuation-dissipation ratio and the rate of growth of the configurational entropy close to the asymptotic state, found empirically in mean-field solutions. (author)

Equilibrium gas-oil ratio measurements using a microfluidic technique.

Science.gov (United States)

Fisher, Robert; Shah, Mohammad Khalid; Eskin, Dmitry; Schmidt, Kurt; Singh, Anil; Molla, Shahnawaz; Mostowfi, Farshid

2013-07-07

A method for measuring the equilibrium GOR (gas-oil ratio) of reservoir fluids using microfluidic technology is developed. Live crude oils (crude oil with dissolved gas) are injected into a long serpentine microchannel at reservoir pressure. The fluid forms a segmented flow as it travels through the channel. Gas and liquid phases are produced from the exit port of the channel that is maintained at atmospheric conditions. The process is analogous to the production of crude oil from a formation. By using compositional analysis and thermodynamic principles of hydrocarbon fluids, we show excellent equilibrium between the produced gas and liquid phases is achieved. The GOR of a reservoir fluid is a key parameter in determining the equation of state of a crude oil. Equations of state that are commonly used in petroleum engineering and reservoir simulations describe the phase behaviour of a fluid at equilibrium state. Therefore, to accurately determine the coefficients of an equation of state, the produced gas and liquid phases have to be as close to the thermodynamic equilibrium as possible. In the examples presented here, the GORs measured with the microfluidic technique agreed with GOR values obtained from conventional methods. Furthermore, when compared to conventional methods, the microfluidic technique was simpler to perform, required less equipment, and yielded better repeatability.

The Lewis Chemical Equilibrium Program with parametric study capability

Science.gov (United States)

Sevigny, R.

1981-01-01

The program was developed to determine chemical equilibrium in complex systems. Using a free energy minimization technique, the program permits calculations such as: chemical equilibrium for assigned thermodynamic states; theoretical rocket performance for both equilibrium and frozen compositions during expansion; incident and reflected shock properties; and Chapman-Jouget detonation properties. It is shown that the same program can handle solid coal in an entrained flow coal gasification problem.

Information theory explanation of the fluctuation theorem, maximum entropy production and self-organized criticality in non-equilibrium stationary states

CERN Document Server

Dewar, R

2003-01-01

Jaynes' information theory formalism of statistical mechanics is applied to the stationary states of open, non-equilibrium systems. First, it is shown that the probability distribution p subGAMMA of the underlying microscopic phase space trajectories GAMMA over a time interval of length tau satisfies p subGAMMA propor to exp(tau sigma subGAMMA/2k sub B) where sigma subGAMMA is the time-averaged rate of entropy production of GAMMA. Three consequences of this result are then derived: (1) the fluctuation theorem, which describes the exponentially declining probability of deviations from the second law of thermodynamics as tau -> infinity; (2) the selection principle of maximum entropy production for non-equilibrium stationary states, empirical support for which has been found in studies of phenomena as diverse as the Earth's climate and crystal growth morphology; and (3) the emergence of self-organized criticality for flux-driven systems in the slowly-driven limit. The explanation of these results on general inf...

Thermodynamic chemical energy transfer mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium chemical reactions

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

Conformational stability and self-association equilibrium in biologics.

Science.gov (United States)

Clarkson, Benjamin R; Schön, Arne; Freire, Ernesto

2016-02-01

Biologics exist in equilibrium between native, partially denatured, and denatured conformational states. The population of any of these states is dictated by their Gibbs energy and can be altered by changes in physical and solution conditions. Some conformations have a tendency to self-associate and aggregate, an undesirable phenomenon in protein therapeutics. Conformational equilibrium and self-association are linked thermodynamic functions. Given that any associative reaction is concentration dependent, conformational stability studies performed at different protein concentrations can provide early clues to future aggregation problems. This analysis can be applied to the selection of protein variants or the identification of better formulation solutions. In this review, we discuss three different aggregation situations and their manifestation in the observed conformational equilibrium of a protein. Copyright © 2015 Elsevier Ltd. All rights reserved.

Computation of Phase Equilibrium and Phase Envelopes

DEFF Research Database (Denmark)

Ritschel, Tobias Kasper Skovborg; Jørgensen, John Bagterp

formulate the involved equations in terms of the fugacity coefficients. We present expressions for the first-order derivatives. Such derivatives are necessary in computationally efficient gradient-based methods for solving the vapor-liquid equilibrium equations and for computing phase envelopes. Finally, we......In this technical report, we describe the computation of phase equilibrium and phase envelopes based on expressions for the fugacity coefficients. We derive those expressions from the residual Gibbs energy. We consider 1) ideal gases and liquids modeled with correlations from the DIPPR database...... and 2) nonideal gases and liquids modeled with cubic equations of state. Next, we derive the equilibrium conditions for an isothermal-isobaric (constant temperature, constant pressure) vapor-liquid equilibrium process (PT flash), and we present a method for the computation of phase envelopes. We...

Stochastic approach to equilibrium and nonequilibrium thermodynamics.

Science.gov (United States)

Tomé, Tânia; de Oliveira, Mário J

2015-04-01

We develop the stochastic approach to thermodynamics based on stochastic dynamics, which can be discrete (master equation) and continuous (Fokker-Planck equation), and on two assumptions concerning entropy. The first is the definition of entropy itself and the second the definition of entropy production rate, which is non-negative and vanishes in thermodynamic equilibrium. Based on these assumptions, we study interacting systems with many degrees of freedom in equilibrium or out of thermodynamic equilibrium and how the macroscopic laws are derived from the stochastic dynamics. These studies include the quasiequilibrium processes; the convexity of the equilibrium surface; the monotonic time behavior of thermodynamic potentials, including entropy; the bilinear form of the entropy production rate; the Onsager coefficients and reciprocal relations; and the nonequilibrium steady states of chemical reactions.

Simulation Research on Vehicle Active Suspension Controller Based on G1 Method

Science.gov (United States)

Li, Gen; Li, Hang; Zhang, Shuaiyang; Luo, Qiuhui

2017-09-01

Based on the order relation analysis method (G1 method), the optimal linear controller of vehicle active suspension is designed. The system of the main and passive suspension of the single wheel vehicle is modeled and the system input signal model is determined. Secondly, the system motion state space equation is established by the kinetic knowledge and the optimal linear controller design is completed with the optimal control theory. The weighting coefficient of the performance index coefficients of the main passive suspension is determined by the relational analysis method. Finally, the model is simulated in Simulink. The simulation results show that: the optimal weight value is determined by using the sequence relation analysis method under the condition of given road conditions, and the vehicle acceleration, suspension stroke and tire motion displacement are optimized to improve the comprehensive performance of the vehicle, and the active control is controlled within the requirements.

Morphological instability of a non-equilibrium ice-colloid interface

KAUST Repository

Peppin, S. S. L.

2009-10-02

We assess the morphological stability of a non-equilibrium ice-colloidal suspension interface, and apply the theory to bentonite clay. An experimentally convenient scaling is employed that takes advantage of the vanishing segregation coefficient at low freezing velocities, and when anisotropic kinetic effects are included, the interface is shown to be unstable to travelling waves. The potential for travelling-wave modes reveals a possible mechanism for the polygonal and spiral ice lenses observed in frozen clays. A weakly nonlinear analysis yields a long-wave evolution equation for the interface shape containing a new parameter related to the highly nonlinear liquidus curve in colloidal systems. We discuss the implications of these results for the frost susceptibility of soils and the fabrication of microtailored porous materials. © 2009 The Royal Society.

Non-equilibrium dynamics and floral trait interactions shape extant angiosperm diversity.

Science.gov (United States)

O'Meara, Brian C; Smith, Stacey D; Armbruster, W Scott; Harder, Lawrence D; Hardy, Christopher R; Hileman, Lena C; Hufford, Larry; Litt, Amy; Magallón, Susana; Smith, Stephen A; Stevens, Peter F; Fenster, Charles B; Diggle, Pamela K

2016-05-11

Why are some traits and trait combinations exceptionally common across the tree of life, whereas others are vanishingly rare? The distribution of trait diversity across a clade at any time depends on the ancestral state of the clade, the rate at which new phenotypes evolve, the differences in speciation and extinction rates across lineages, and whether an equilibrium has been reached. Here we examine the role of transition rates, differential diversification (speciation minus extinction) and non-equilibrium dynamics on the evolutionary history of angiosperms, a clade well known for the abundance of some trait combinations and the rarity of others. Our analysis reveals that three character states (corolla present, bilateral symmetry, reduced stamen number) act synergistically as a key innovation, doubling diversification rates for lineages in which this combination occurs. However, this combination is currently less common than predicted at equilibrium because the individual characters evolve infrequently. Simulations suggest that angiosperms will remain far from the equilibrium frequencies of character states well into the future. Such non-equilibrium dynamics may be common when major innovations evolve rarely, allowing lineages with ancestral forms to persist, and even outnumber those with diversification-enhancing states, for tens of millions of years. © 2016 The Author(s).

Equation of state of charged latex suspensions

International Nuclear Information System (INIS)

Reus, Valerie

1995-01-01

We measured the osmotic pressure of charged bromo-polystyrene particles suspensions in the dilute System (0,01-10% in volume fraction). The typical range of differences in water heights varies from one millimeter to a few centimeters. When particles are polydisperse, samples remain always sols but if particles are monodisperse, they can form supramolecular crystals stabilized by electrostatic repulsions. These crystals exist only when the ionic force is very low, about one μmole/l. We determined the structure of these assemblies by light and X-ray scattering as function of the volume fraction. At low volume fractions, crystals adopt a body centered cubic structure; when the concentration increases, they become more compact and we observe face centered cubic structures. After shearing, defects may appear and two dimensional hexagonal structures can be found. This type of study of the osmotic pressure versus distance (in the range 300 nm) is equivalent to a highly precise atomic force measurement, since it allows detection of forces as small as 10 -11 -10 -12 N. (author) [fr

Nanoscale Correlated Disorder in Out-of-Equilibrium Myelin Ultrastructure.

Science.gov (United States)

Campi, Gaetano; Di Gioacchino, Michael; Poccia, Nicola; Ricci, Alessandro; Burghammer, Manfred; Ciasca, Gabriele; Bianconi, Antonio

2018-01-23

Ultrastructural fluctuations at nanoscale are fundamental to assess properties and functionalities of advanced out-of-equilibrium materials. We have taken myelin as a model of supramolecular assembly in out-of-equilibrium living matter. Myelin sheath is a simple stable multilamellar structure of high relevance and impact in biomedicine. Although it is known that myelin has a quasi-crystalline ultrastructure, there is no information on its fluctuations at nanoscale in different states due to limitations of the available standard techniques. To overcome these limitations, we have used scanning micro X-ray diffraction, which is a unique non-invasive probe of both reciprocal and real space to visualize statistical fluctuations of myelin order of the sciatic nerve of Xenopus laevis. The results show that the ultrastructure period of the myelin is stabilized by large anticorrelated fluctuations at nanoscale, between hydrophobic and hydrophilic layers. The ratio between the total thickness of hydrophilic and hydrophobic layers defines the conformational parameter, which describes the different states of myelin. Our key result is that myelin in its out-of-equilibrium functional state fluctuates point-to-point between different conformations showing a correlated disorder described by a Levy distribution. As the system approaches the thermodynamic equilibrium in an aged state, the disorder loses its correlation degree and the structural fluctuation distribution changes to Gaussian. In a denatured state at low pH, it changes to a completely disordered stage. Our results aim to clarify the degradation mechanism in biological systems by associating these states with ultrastructural dynamic fluctuations at nanoscale.

Controlling active cabin suspensions in commercial vehicles

NARCIS (Netherlands)

Evers, W.J.E.; Besselink, I.J.M.; Teerhuis, A.P.; Knaap, van der A.C.M.; Nijmeijer, H.

2009-01-01

The field of automotive suspensions is changing. Semi-active and active suspensions are starting to become viable options for vehicle designers. Suspension design for commercial vehicles is especially interesting given its potential. An active cabin suspension for a heavy-duty truck is considered,

EDITORIAL: Colloidal suspensions Colloidal suspensions

Science.gov (United States)

Petukhov, Andrei; Kegel, Willem; van Duijneveldt, Jeroen

2011-05-01

N W 2002 Nature 416 811 [9] Borsboom M et al 1998 J. Synchrotron Radiat. 5 518 [10] Zernike F and Prins J A 1927 Z. Phys. 41 184 Colloidal suspensions contents How much does the core structure of a three-phase contact line contribute to the line tension near a wetting transition? J O Indekeu, K Koga and B Widom A systematic coarse-graining strategy for semi-dilute copolymer solutions: from monomers to micelles Barbara Capone, Ivan Coluzza and Jean-Pierre Hansen Structural searches using isopointal sets as generators: densest packings for binary hard sphere mixtures Toby S Hudson and Peter Harrowell The theory of delamination during drying of confined colloidal suspensions K J Wallenstein and W B Russel Electrostatics Modeling of equilibrium hollow objects stabilized by electrostatics Ethayaraja Mani, Jan Groenewold and Willem K Kegel The Donnan equilibrium: I. On the thermodynamic foundation of the Donnan equation of state A Philipse and A Vrij Colloidal rods and platelets Cholesteric order in systems of helical Yukawa rods H H Wensink and G Jackson Magnetic-field-induced nematic-nematic phase separation and droplet formation in colloidal goethite E van den Pol, A A Verhoeff, A Lupascu, M A Diaconeasa, P Davidson, I Dozov, B W M Kuipers, D M E Thies-Weesie and G J Vroege Structure of colloidal sphere-plate mixtures N Doshi, G Cinacchi, J S van Duijneveldt, T Cosgrove, S W Prescott, I Grillo, J Phipps and D I Gittins 3D structure of nematic and columnar phases of hard colloidal platelets A B G M Leferink op Reinink, J M Meijer, D Kleshchanok, D V Byelov, G J Vroege, A V Petukhov and H N W Lekkerkerker Phase behaviour of binary mixtures of diamagnetic colloidal platelets in an external magnetic field Jonathan Phillips and Matthias Schmidt Rheo-SAXS investigation of shear-thinning behaviour of very anisometric repulsive disc-like clay suspensions A M Philippe, C Baravian, M Imperor-Clerc, J De Silva, E Paineau, I Bihannic, P Davidson, F Meneau, P Levitz and L J Michot

Electrohydrodynamics of suspension of liquid drops in AC fields

Science.gov (United States)

Abdul Halim, Md.; Esmaeeli, Asghar

2012-11-01

Manipulation of liquid drops by an externally applied electric field is currently the focus of increased attention because of its relevance in a broad range of industrial processes. The effect of a uniform DC electric field on a solitary drop is well studied; however, less is know about the impact of electric field on suspension of liquid drops, and very little information is available on the impact of AC field on a single or a suspension of drops. Here we report the results of Direct Numerical Simulations of electrohydrodynamics of suspension of liquid drops. The governing equations are solved using a front tracking/finite difference technique, in conjunction with Taylor's leaky dielectric model. The imposed electric potential comprises of two parts, a time-independent base and a time-dependent part. The goal is to explore the relative importance of these two components in setting the statistically steady state behavior of the suspension. To this end, we report the results of three sets of simulations, where (i) the time-dependent part act as a perturbation on the base potential, (ii) the two components are of the same order, and (iii) the time-dependent part is much larger than the base potential. The problem is studied as a function of the governing nondimensional parameters.

Suspensions with reduced violin string modes

International Nuclear Information System (INIS)

Lee, B H; Ju, L; Blair, D G

2006-01-01

We discuss the possibility of significantly reducing the number and Q-factor of violin string modes in the mirror suspension. Simulations of a bar-flexure suspension and an orthogonal ribbon have shown a reduction in the number of violin string modes when compared to a normal ribbon suspension. By calculating the expected suspension thermal noise, we find that the orthogonal ribbon provides a promising suspension alternative. A lower number of violin modes oscillating in the direction of the laser and a reduction in violin mode peak values of at least 23dB can be achieved with a slight increase in thermal noise above 40Hz

Suspensions with reduced violin string modes

Energy Technology Data Exchange (ETDEWEB)

Lee, B H; Ju, L; Blair, D G [School of Physics, University of Western Australia, Crawley 6009, WA (Australia)

2006-03-02

We discuss the possibility of significantly reducing the number and Q-factor of violin string modes in the mirror suspension. Simulations of a bar-flexure suspension and an orthogonal ribbon have shown a reduction in the number of violin string modes when compared to a normal ribbon suspension. By calculating the expected suspension thermal noise, we find that the orthogonal ribbon provides a promising suspension alternative. A lower number of violin modes oscillating in the direction of the laser and a reduction in violin mode peak values of at least 23dB can be achieved with a slight increase in thermal noise above 40Hz.

A molecular dynamics study of liquid layering and thermal conductivity enhancement in nanoparticle suspensions

Science.gov (United States)

Paul, J.; Madhu, A. K.; Jayadeep, U. B.; Sobhan, C. B.; Peterson, G. P.

2018-03-01

Liquid layering is considered to be one of the factors contributing to the often anomalous enhancement in thermal conductivity of nanoparticle suspensions. The extent of this layering was found to be significant at lower particle sizes, as reported in an earlier work by the authors. In continuation to that work, an investigation was conducted to better understand the fundamental parameters impacting the reported anomalous enhancement in thermal conductivity of nanoparticle suspensions (nanofluids), utilizing equilibrium molecular dynamics simulations in a copper-argon system. Nanofluids containing nanoparticles of size less than 6 nm were investigated and studied analytically. The heat current auto-correlation function in the Green-Kubo formulation for thermal conductivity was decomposed into self-correlations and cross-correlations of different species and the kinetic, potential, collision and enthalpy terms of the dominant portion of the heat current vector. The presence of liquid layering around the nanoparticle was firmly established through simulations that show the dominant contribution of Ar-Ar self-correlation and the trend displayed by the kinetic-potential cross-correlation within the argon species.

Core-state models for fuel management of equilibrium and transition cycles in pressurized water reactors

International Nuclear Information System (INIS)

Aragones, J.M.; Martinez-Val, J.M.; Corella, M.R.

1977-01-01

Fuel management requires that mass, energy, and reactivity balance be satisfied in each reload cycle. Procedures for selection of alternatives, core-state models, and fuel cost calculations have been developed for both equilibrium and transition cycles. Effective cycle lengths and fuel cycle variables--namely, reload batch size, schedule of incore residence for the fuel, feed enrichments, energy sharing cycle by cycle, and discharge burnup and isotopics--are the variables being considered for fuel management planning with a given energy generation plan, fuel design, recycling strategy, and financial assumptions

Magneto-rheological suspensions for improving ground vehicle's ride comfort, stability, and handling

Science.gov (United States)

Ahmadian, Mehdi

2017-10-01

A state-of-the-art discussion on the applications of magneto-rheological (MR) suspensions for improving ride comfort, handling, and stability in ground vehicles is discussed for both road and rail applications. A historical perspective on the discovery and engineering development of MR fluids is presented, followed by some of the common methods for modelling their non-Newtonian behaviour. The common modes of the MR fluids are discussed, along with the application of the fluid in valve mode for ground vehicles' dampers (or shock absorbers). The applications span across nearly all road vehicles, including automobiles, trains, semi-trucks, motorcycles, and even bicycles. For each type of vehicle, the results of some of the past studies is presented briefly, with reference to the originating study. It is discussed that Past experimental and modelling studies have indicated that MR suspensions provide clear advantages for ground vehicles that far surpasses the performance of passive suspension. For rail vehicles, the primary advantage is in terms of increasing the speed at which the onset of hunting occurs, whereas for road vehicles - mainly automobiles - the performance improvements are in terms of a better balance between vehicle ride, handling, and stability. To further elaborate on this point, a single-suspension model is used to develop an index-based approach for studying the compromise that is offered by vehicle suspensions, using the H2 optimisation approach. Evaluating three indices based on the sprung-mass acceleration, suspension rattlespace, and tyre deflection, it is clearly demonstrated that MR suspensions significantly improve road vehicle's ride comfort, stability, and handling in comparison with passive suspensions. For rail vehicles, the simulation results indicate that using MR suspensions with an on-off switching control can increase the speed at which the on-set of hunting occurs by as much as 50% to more than 300%.

Non-equilibrium steady states: maximization of the Shannon entropy associated with the distribution of dynamical trajectories in the presence of constraints

International Nuclear Information System (INIS)

Monthus, Cécile

2011-01-01

Filyokov and Karpov (1967 Inzh.-Fiz. Zh. 13 624) have proposed a theory of non-equilibrium steady states in direct analogy with the theory of equilibrium states: the principle is to maximize the Shannon entropy associated with the probability distribution of dynamical trajectories in the presence of constraints, including the macroscopic current of interest, via the method of Lagrange multipliers. This maximization leads directly to the generalized Gibbs distribution for the probability distribution of dynamical trajectories, and to some fluctuation relation of the integrated current. The simplest stochastic dynamics where these ideas can be applied are discrete-time Markov chains, defined by transition probabilities W i→j between configurations i and j: instead of choosing the dynamical rules W i→j a priori, one determines the transition probabilities and the associate stationary state that maximize the entropy of dynamical trajectories with the other physical constraints that one wishes to impose. We give a self-contained and unified presentation of this type of approach, both for discrete-time Markov chains and for continuous-time master equations. The obtained results are in full agreement with the Bayesian approach introduced by Evans (2004 Phys. Rev. Lett. 92 150601) under the name 'Non-equilibrium Counterpart to detailed balance', and with the 'invariant quantities' derived by Baule and Evans (2008 Phys. Rev. Lett. 101 240601), but provide a slightly different perspective via the formulation in terms of an eigenvalue problem

Effect of suspension characteristics on in-flight particle properties and coating microstructures achieved by suspension plasma spray

Science.gov (United States)

Aubignat, E.; Planche, M. P.; Allimant, A.; Billières, D.; Girardot, L.; Bailly, Y.; Montavon, G.

2014-11-01

This paper focuses on the influence of suspension properties on the manufacturing of coatings by suspension plasma spraying (SPS). For this purpose, alumina suspensions were formulated with two different liquid phases: water and ethanol. Suspensions were atomized with a twin-fluid nozzle and injected in an atmospheric plasma jet. Suspension injection was optimized thanks to shadowgraphy observations and drop size distribution measurements performed by laser diffraction. In-flight particle velocities were evaluated by particle image velocimetry. In addition, splats were collected on glass substrates, with the same conditions as the ones used during the spray process. Scanning electron microscopy (SEM) and profilometry analyses were then performed to observe the splat morphology and thus to get information on plasma / suspension interactions, such as particle agglomeration. Finally, coatings were manufactured, characterized by SEM and compared to each other.

Quenching of Particle-Gas Combustible Mixtures Using Electric Particulate Suspension (EPS) and Dispersion Methods

Science.gov (United States)

Colver, Gerald M.; Goroshin, Samuel; Lee, John H. S.

2001-01-01

A cooperative study is being carried out between Iowa State University and McGill University. The new study concerns wall and particle quenching effects in particle-gas mixtures. The primary objective is to measure and interpret flame quenching distances, flammability limits, and burning velocities in particulate suspensions. A secondary objective is to measure particle slip velocities and particle velocity distribution as these influence flame propagation. Two suspension techniques will be utilized and compared: (1) electric particle suspension/EPS; and (2) flow dispersion. Microgravity tests will permit testing of larger particles and higher and more uniform dust concentrations than is possible in normal gravity.

Neutron scattering on equilibrium and nonequilibrium phonons, excitons and polaritons

International Nuclear Information System (INIS)

Broude, V.L.; Sheka, E.F.

1978-01-01

A number of problems of solid-state physics representing interest for neutron spectroscopy of future is considered. The development of the neutron inelastic scattering spectroscopy (neutron spectroscopy of equilibrium phonons) is discussed with application to nuclear dynamics of crystals in the thermodynamic equilibrium. The results of high-flux neutron source experiments on molecular crystals are presented. The advantages of neutron inelastic scattering over optical spectroscopy are discussed. The spectroscopy of quasi-equilibrium and non-equilibrium quasi-particles is discussed. In particular, the neutron scattering on polaritons, excitons in thermal equilibrium and production of light-excitons are considered. The problem of the possibility of such experiments is elucidated

Non-equilibrium dynamics from RPMD and CMD.

Science.gov (United States)

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.

Quantum hair of black holes out of equilibrium

Science.gov (United States)

Brustein, Ram; Medved, A. J. M.

2018-02-01

Classically, the black hole (BH) horizon is completely opaque, hiding any clues about the state and very existence of its interior. Quantum mechanically and in equilibrium, the situation is not much different; Hawking radiation will now be emitted, but it comes out at an extremely slow rate, is thermal to a high degree of accuracy, and thus carries a minimal amount of information about the quantum state within the BH. Here, it is shown that the situation is significantly different when a quantum BH is out of equilibrium. We argue that the BH can then emit "supersized" Hawking radiation with a much larger amplitude than that emitted in equilibrium. The result is a new type of quantum hair that can reveal the state and composition of the BH interior to an external observer. Moreover, the frequency and amplitude of the new hair can be explained by the observer without invoking any new physical principles. The new hair decays at a parametrically slow rate in comparison to the Schwarzschild time scale and can be detected through the emission of gravitational waves (and possibly other types of waves) whenever a BH has received a large enough surge in energy to move it far away from its equilibrium state, in particular, during and immediately after a BH-merger event. The current discussion is motivated by a previous analysis, in the context of a recently proposed polymer model for the BH interior, that implies emissions just like those described here. We expect, however, that the new hair is a model-independent property of quantum BHs.

Uranium, thorium and potassium contents and radioactive equilibrium states of the uranium and thorium series nuclides in phosphate rocks and phosphate fertilizers

Energy Technology Data Exchange (ETDEWEB)

Komura, K; Yanagisawa, M; Sakurai, J; Sakanoue, M

1985-10-01

Uranium, thorium and potassium contents and radioactive equilibrium states of the uranium and thorium series nuclides have been studied for 2 phosphate rocks and 7 phosphate fertilizers. Uranium contents were found to be rather high (39-117 ppm) except for phosphate rock from Kola. The uranium series nuclides were found to be in various equilibration states, which can be grouped into following three categories. Almost in the equilibrium state, 238U approximately 230Th greater than 210Pb greater than 226Ra and 238U greater than 230Th greater than 210Pb greater than 226Ra. Thorium contents were found to be, in general, low and appreciable disequilibrium of the thorium series nuclides was not observed except one sample. Potassium contents were also very low (less than 0.3% K2O) except for complex fertilizers. Based on the present data, discussions were made for the radiation exposure due to phosphate fertilizers.

49 CFR 570.8 - Suspension systems.

Science.gov (United States)

2010-10-01

... 49 Transportation 6 2010-10-01 2010-10-01 false Suspension systems. 570.8 Section 570.8 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY... Pounds or Less § 570.8 Suspension systems. (a) Suspension condition. Ball joint seals shall not be cut or...

Soils apart from equilibrium – consequences for soil carbon balance modelling

Directory of Open Access Journals (Sweden)

T. Wutzler

2007-01-01

Full Text Available Many projections of the soil carbon sink or source are based on kinetically defined carbon pool models. Para-meters of these models are often determined in a way that the steady state of the model matches observed carbon stocks. The underlying simplifying assumption is that observed carbon stocks are near equilibrium. This assumption is challenged by observations of very old soils that do still accumulate carbon. In this modelling study we explored the consequences of the case where soils are apart from equilibrium. Calculation of equilibrium states of soils that are currently accumulating small amounts of carbon were performed using the Yasso model. It was found that already very small current accumulation rates cause big changes in theoretical equilibrium stocks, which can virtually approach infinity. We conclude that soils that have been disturbed several centuries ago are not in equilibrium but in a transient state because of the slowly ongoing accumulation of the slowest pool. A first consequence is that model calibrations to current carbon stocks that assume equilibrium state, overestimate the decay rate of the slowest pool. A second consequence is that spin-up runs (simulations until equilibrium overestimate stocks of recently disturbed sites. In order to account for these consequences, we propose a transient correction. This correction prescribes a lower decay rate of the slowest pool and accounts for disturbances in the past by decreasing the spin-up-run predicted stocks to match an independent estimate of current soil carbon stocks. Application of this transient correction at a Central European beech forest site with a typical disturbance history resulted in an additional carbon fixation of 5.7±1.5 tC/ha within 100 years. Carbon storage capacity of disturbed forest soils is potentially much higher than currently assumed. Simulations that do not adequately account for the transient state of soil carbon stocks neglect a considerable

Theoretical investigation of tautomeric equilibrium in ortho-hydroxy phenyl Schiff bases

Science.gov (United States)

Kluba, M.; Lipkowski, P.; Filarowski, A.

2008-10-01

This Letter presents a study of the tautomeric equilibrium in ortho-hydroxy phenyl Schiff bases. The influence of substitution and solvent (simulated by the self-consistent reaction field model, SCRF) on the energy barrier of the transition state and on proton transfer is investigated. Dependencies of the HOMA and HOSE aromaticity indices on the molecular, transition state, and proton transfer forms were obtained. The state of chelate chain and phenyl ring aromaticity depending on the tautomeric equilibrium is studied.

"Non-equilibrium" block copolymer micelles with glassy cores: a predictive approach based on theory of equilibrium micelles.

Science.gov (United States)

Nagarajan, Ramanathan

2015-07-01

Micelles generated in water from most amphiphilic block copolymers are widely recognized to be non-equilibrium structures. Typically, the micelles are prepared by a kinetic process, first allowing molecular scale dissolution of the block copolymer in a common solvent that likes both the blocks and then gradually replacing the common solvent by water to promote the hydrophobic blocks to aggregate and create the micelles. The non-equilibrium nature of the micelle originates from the fact that dynamic exchange between the block copolymer molecules in the micelle and the singly dispersed block copolymer molecules in water is suppressed, because of the glassy nature of the core forming polymer block and/or its very large hydrophobicity. Although most amphiphilic block copolymers generate such non-equilibrium micelles, no theoretical approach to a priori predict the micelle characteristics currently exists. In this work, we propose a predictive approach for non-equilibrium micelles with glassy cores by applying the equilibrium theory of micelles in two steps. In the first, we calculate the properties of micelles formed in the mixed solvent while true equilibrium prevails, until the micelle core becomes glassy. In the second step, we freeze the micelle aggregation number at this glassy state and calculate the corona dimension from the equilibrium theory of micelles. The condition when the micelle core becomes glassy is independently determined from a statistical thermodynamic treatment of diluent effect on polymer glass transition temperature. The predictions based on this "non-equilibrium" model compare reasonably well with experimental data for polystyrene-polyethylene oxide diblock copolymer, which is the most extensively studied system in the literature. In contrast, the application of the equilibrium model to describe such a system significantly overpredicts the micelle core and corona dimensions and the aggregation number. The non-equilibrium model suggests ways to

Design analysis of formula student race car suspension system

Science.gov (United States)

Wirawan, Julian Wisnu; Ubaidillah, Aditra, Rama; Alnursyah, Rafli; Rahman, Rizki Abdul; Cahyono, Sukmaji Indro

2018-02-01

Design analysis of suspension especially for racecar suspension is very crucial to achieve maximum performance and handling. Suspension design may vary depending on the road terrain and the vehicle purpose itself, such as high speed or off-road vehicle. This paper focused on the suspension which used for racecar vehicle. The suspension type used was unequal double wishbone. This model is used because of its stability for high-speed usage compared to another kind of suspension. The suspension parameter was calculated to achieve desired performance. The result is the motion ratio of the designed suspension geometry. The obtained value of motion ratio was 1:2 for front suspension and 1:1 for the rear suspension. These calculation result the front suspension is still too soft, which the optimal motion ratio should be kept around 1:1 for better handling. This problem caused by the lack of space for suspension linkage.

Fixed Points in Grassmannians with Applications to Economic Equilibrium

DEFF Research Database (Denmark)

Keiding, Hans

2017-01-01

In some applications of equilibrium theory, the fixed point involves not only a state and a value of a parameter in the dual of the state space, but also a particular subspace of the state space. Since the set of all subspaces of a finite-dimensional Euclidean space has a structure which does...... not allow immediate application of fixed point theorems, the problem must be reformulated using a suitable parametrization of subspaces. One such parametrization, the Plücker coordinates, is used here to prove a general equilibrium existence theorem. Applications to economic problems involving hierarchies...... of consumers or incomplete markets with real assets are outlined....

Thermodynamics of open, nonisothermal chemical systems far from equilibrium

International Nuclear Information System (INIS)

Yoshida, Nobuo

1992-01-01

The thermodynamic behavior of kinetic models based on a continuously stirred tank reactor (CSTR) is studied in an attempt to seek general trends in the thermodynamic properties of open nonlinear systems. The models consist of two reversible reactions, A + nB rightleftharpoons (n + 1) B (n = 0,1,or 2) and B rightleftharpoons C, taking place in an adiabatic CSTR. The heat of reaction is incorporated, and the rate constants are assumed to follow an Arrhenius temperature dependence. The models give rise to multiple stationary states and sustained oscillations (limit cycles). The entropy difference between stationary or oscillatory states and equilibrium and the rate of entropy production in the these states are calculated as a function of the residence time in the reactor. The entropy difference and entropy production may be taken, to some extent, as indicative of the influence of irreversible processes, which disappears at equilibrium. The results of the calculations reveal the following systematic trends: (I) The entropy difference or entropy production for stable states or both always increase as the residence time is shortened, namely, as the system is displaced further from equilibrium. (II) If stable and unstable states (stationary or oscillatory) coexist under identical conditions, then the stable state invariably has a smaller value of the entropy difference or entropy production or both than the corresponding unstable state. 26 refs., 3 figs

Equilibrium and non-equilibrium phenomena in arcs and torches

NARCIS (Netherlands)

Mullen, van der J.J.A.M.

2000-01-01

A general treatment of non-equilibrium plasma aspects is obtained by relating transport fluxes to equilibrium restoring processes in so-called disturbed Bilateral Relations. The (non) equilibrium stage of a small microwave induced plasma serves as case study.

49 CFR 570.61 - Suspension system.

Science.gov (United States)

2010-10-01

... 49 Transportation 6 2010-10-01 2010-10-01 false Suspension system. 570.61 Section 570.61... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION VEHICLE IN USE INSPECTION STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.61 Suspension system. (a) Suspension condition. Ball joint seals shall not be cut...

Self-organization of dissipative and coherent vortex structures in non-equilibrium magnetized two-dimensional plasmas

International Nuclear Information System (INIS)

Bystrenko, O; Bystrenko, T

2010-01-01

The properties of non-equilibrium magnetized plasmas confined in planar geometry are studied on the basis of first-principle microscopic Langevin dynamics computer simulations. The non-equilibrium state of plasmas is maintained due to the recombination and generation of charges. The intrinsic microscopic structure of non-equilibrium steady-state magnetized plasmas, in particular the inter-particle correlations and self-organization of vortex structures, are examined. The simulations have been performed for a wide range of parameters including strong plasma coupling, high charge recombination and generation rates and intense magnetic field. As is shown in simulations, the non-equilibrium recombination and generation processes trigger the formation of ordered dissipative or coherent drift vortex states in 2D plasmas with distinctly spatially separated components, which are far from thermal equilibrium. This is evident from the unusual properties of binary distributions and behavior of the Coulomb energy of the system, which turn out to be quite different from the ones typical for the equilibrium state of plasmas under the same conditions.

Violations of local equilibrium and linear response in classical lattice systems

International Nuclear Information System (INIS)

Aoki, Kenichiro; Kusnezov, Dimitri

2003-01-01

We quantitatively and systematically analyze how local equilibrium, and linear response in transport are violated as systems move far from equilibrium. This is done by studying heat flow in classical lattice models with and without bulk transport behavior, in 1-3 dimensions, at various temperatures. Equations of motion for the system are integrated numerically to construct the non-equilibrium steady states. Linear response and local equilibrium assumptions are seen to break down in a similar manner. We quantify the breakdown through the analysis of both microscopic and macroscopic observables and examine its transformation properties under general redefinitions of the non-equilibrium temperature

Compressible Fluid Suspension Performance Testing

National Research Council Canada - National Science Library

Hoogterp, Francis

2003-01-01

... compressible fluid suspension system that was designed and installed on the vehicle by DTI. The purpose of the tests was to evaluate the possible performance benefits of the compressible fluid suspension system...

Equilibrium-constant expressions for aqueous plutonium

International Nuclear Information System (INIS)

Silver, G.L.

2010-01-01

Equilibrium-constant expressions for Pu disproportionation reactions traditionally contain three or four terms representing the concentrations or fractions of the oxidation states. The expressions can be rewritten so that one of the oxidation states is replaced by a term containing the oxidation number of the plutonium. Experimental estimations of the numerical values of the constants can then be checked in several ways. (author)

Teaching Chemical Equilibrium with the Jigsaw Technique

Science.gov (United States)

Doymus, Kemal

2008-03-01

This study investigates the effect of cooperative learning (jigsaw) versus individual learning methods on students’ understanding of chemical equilibrium in a first-year general chemistry course. This study was carried out in two different classes in the department of primary science education during the 2005-2006 academic year. One of the classes was randomly assigned as the non-jigsaw group (control) and other as the jigsaw group (cooperative). Students participating in the jigsaw group were divided into four “home groups” since the topic chemical equilibrium is divided into four subtopics (Modules A, B, C and D). Each of these home groups contained four students. The groups were as follows: (1) Home Group A (HGA), representin g the equilibrium state and quantitative aspects of equilibrium (Module A), (2) Home Group B (HGB), representing the equilibrium constant and relationships involving equilibrium constants (Module B), (3) Home Group C (HGC), representing Altering Equilibrium Conditions: Le Chatelier’s principle (Module C), and (4) Home Group D (HGD), representing calculations with equilibrium constants (Module D). The home groups then broke apart, like pieces of a jigsaw puzzle, and the students moved into jigsaw groups consisting of members from the other home groups who were assigned the same portion of the material. The jigsaw groups were then in charge of teaching their specific subtopic to the rest of the students in their learning group. The main data collection tool was a Chemical Equilibrium Achievement Test (CEAT), which was applied to both the jigsaw and non-jigsaw groups The results indicated that the jigsaw group was more successful than the non-jigsaw group (individual learning method).

Phosphate Suspension Chromium (III) radiolabelled with 32P and 90Y

International Nuclear Information System (INIS)

Cruz Arencibia, Jorge; Turiño Pérez, David; Cruz Morales, Amed; Morín Zorrilla, José; Taylor Delgado, Tamara; García Rodríguez, Enrique; Baganet Cobas, Aymara

2016-01-01

Chronic synovitis is a manifestation common joint of rheumatoid arthritis, hemophilia and other systemic diseases. The modalities of treatment of this complication radiosynoviorthesis stands out for its good response, ease of implementation and lower total cost. In the United States, Europe and some countries in Latin America they are used to this different radioactive colloids and suspensions. In Cuba it was developed and is approved suspension Chromic Phosphate 32 P-labeled. At work the consistency of the production process of this suspension is examined. As a result of the evaluation was found that the suspension is characterized by a radiochemical purity of 94 ± 1% and particle size predominantly of 91 ± 3 between 0.2-10 microns. The results achieved in regular production and application to patients with rheumatic diseases and hemophiliacs, with follow-up to one year prove their efficacy and safety, the latter associated with low leakage articular detected and the absence of adverse reactions. Also at work the results achieved in the development of a technology for the production of suspension Phosphate Chromium (III) labeled with 90 Y, similarly to existing 32 P composition is exposed, and properties even more favorable, in particular radiochemical purity of 97%, favoring the registration of a radiopharmaceutical with better technical and economic characteristics, which must ensures the use of this form of treatment in the country. (author)

A universal suspension test rig for electrohydraulic active and passive automotive suspension system

Directory of Open Access Journals (Sweden)

Mahmoud Omar

2017-12-01

Full Text Available A fully active electro-hydraulic and passive automotive quarter car suspensions with their experimental test-rigs are designed and implemented. Investigation of the active performance compared against the passive is performed experimentally and numerically utilizing SIMULINK's Simscape library. Both systems are modeled as single-degree-of-freedom in order to simplify the validation process. Economic considerations were considered during the rig's implementation. The rig consists of two identical platforms fixed side by side allowing testing two independent suspensions simultaneously. Position sensors for sprung and unsprung masses on both platforms are installed. The road input is introduced by a cam and a roller follower mechanism driven by 1.12 kW single phase induction motor with speed reduction assembly. The active hydraulic cylinder was the most viable choice due to its high power-to-weight ratio. The active control is of the proportional-integral-differential (PID type. Though this technique is quite simple and not new, yet the emphasis of this paper is the engineering, design and implementation of the experimental setup and controller. A successful validation process is performed. Ride comfort significantly improved with active suspension, as shown by the results; 24.8% sprung mass vibration attenuation is achieved. The details of the developed system with the analytical and experimental results are presented. Keywords: Active suspension, Passive suspension, Servo, Hydraulic, Control, PID

Steady equilibrium of a cylindrically symmetric plasma sustained by fueling

International Nuclear Information System (INIS)

Tomita, Yukihiro; Momota, Hiromu

1993-01-01

By introducing a novel and natural method to obtain a steady equilibrium, it is shown that a pressure gradient produced by the particle injection or resultant diamagnetic current can sustain only an equilibrium of a diffused linear pinch. For an extremely elongated FRC where magnetic field vanishes at a certain point, a seed current is needed to sustain configuration in a steady state equilibrium. A directed flow of fusion produced protons forms a seed current and consequently it sustains a steady FRC equilibrium by fueling only once D- 3 He burning takes place. Effects of anomalous transports on the sustainment are discussed. (author)

Quasi-particle states of electron systems out of equilibrium

Czech Academy of Sciences Publication Activity Database

Velický, B.; Kalvová, Anděla; Špička, Václav

2007-01-01

Roč. 75, č. 19 (2007), 195125/1-195125/9 ISSN 1098-0121 R&D Projects: GA ČR GA202/04/0585 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z10100521 Keywords : non-equilibrium * Green’s functions * quantum transport equations * quasi-particles Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.172, year: 2007

Decay of non-equilibrium polariton condensate in semiconductors

International Nuclear Information System (INIS)

Beloussov, I.V.; Shvera, Y.M.

1993-08-01

Excitation dynamics of polariton quantum fluctuations arising in direct-gap semi-conductor as a result of parametric decay of non-equilibrium polariton condensate with non-zero wave vector is studied. The predominant mechanism of polariton scattering is supposed to be exciton-exciton interaction. Steady state which corresponds to the case of dynamic equilibrium between the polariton condensate and quantum fluctuations is obtained. Distribution functions of non-condensate polaritons are localized in the resonant regions, corresponding to two-particle excitation of polaritons from the condensate. The spectrum of elementary excitations in steady state coincides with usual polariton energy with the shift proportional to initial density of polariton condensate. (author). 25 refs

The Mystical Suspension

Directory of Open Access Journals (Sweden)

Héctor Santiesteban Oliva

2016-11-01

Full Text Available Mistical suspension, silence, time, absolute, ontology, ineffability, aletheiaIn the mystical ecstasy there is a sensorial and intellectual suspension when contemplating the absolute, the ontological Being. Silence is not only significant: it is revealing. The greatest expression of experience inner silence . The word is insufficient when the ontological reality is revealed. Revelation or truth , the Greek concept of aletheia, takes on greater significance in that transcendental experience. It is also suspended phenomenological time and remains eternity open.

Stability of equilibrium states in finite samples of smectic C* liquid crystals

International Nuclear Information System (INIS)

Stewart, I W

2005-01-01

Equilibrium solutions for a sample of ferroelectric smectic C (SmC*) liquid crystal in the 'bookshelf' geometry under the influence of a tilted electric field will be presented. A linear stability criterion is identified and used to confirm stability for typical materials possessing either positive or negative dielectric anisotropy. The theoretical response times for perturbations to the equilibrium solutions are calculated numerically and found to be consistent with estimates for response times in ferroelectric smectic C liquid crystals reported elsewhere in the literature for non-tilted fields

A comparison of optimal semi-active suspension systems regarding vehicle ride comfort

Science.gov (United States)

Koulocheris, Dimitrios; Papaioannou, Georgios; Chrysos, Emmanouil

2017-10-01

The aim of this work is to present a comparison of the main semi active suspension systems used in a passenger car, after having optimized the suspension systems of the vehicle model in respect with ride comfort and road holding. Thus, a half car model, equipped with controllable dampers, along with a seat and a driver was implemented. Semi-active suspensions have received a lot of attention since they seem to provide the best compromise between cost (energy consumption, actuators/sensors hardware) and performance in comparison with active and passive suspensions. In this work, the semi active suspension systems studied are comfort oriented and consist of (a) the two version of Skyhook control (two states skyhook and skyhook linear approximation damper), (b) the acceleration driven damper (ADD), (c) the power driven damper (PDD), (d) the combination of Skyhook and ADD (Mixed Skyhook-ADD) and (e) the combination of the two with the use of a sensor. The half car model equipped with the above suspension systems was excited by a road bump, and was optimized using genetic algorithms (GA) in respect with ride comfort and road holding. This study aims to highlight how the optimization of the vehicle model could lead to the best compromise between ride comfort and road holding, overcoming their well-known trade-off. The optimum results were compared with important performance metrics regarding the vehicle’s dynamic behaviour in general.

Entropy production in a fluid-solid system far from thermodynamic equilibrium.

Science.gov (United States)

Chung, Bong Jae; Ortega, Blas; Vaidya, Ashwin

2017-11-24

The terminal orientation of a rigid body in a moving fluid is an example of a dissipative system, out of thermodynamic equilibrium and therefore a perfect testing ground for the validity of the maximum entropy production principle (MaxEP). Thus far, dynamical equations alone have been employed in studying the equilibrium states in fluid-solid interactions, but these are far too complex and become analytically intractable when inertial effects come into play. At that stage, our only recourse is to rely on numerical techniques which can be computationally expensive. In our past work, we have shown that the MaxEP is a reliable tool to help predict orientational equilibrium states of highly symmetric bodies such as cylinders, spheroids and toroidal bodies. The MaxEP correctly helps choose the stable equilibrium in these cases when the system is slightly out of thermodynamic equilibrium. In the current paper, we expand our analysis to examine i) bodies with fewer symmetries than previously reported, for instance, a half-ellipse and ii) when the system is far from thermodynamic equilibrium. Using two-dimensional numerical studies at Reynolds numbers ranging between 0 and 14, we examine the validity of the MaxEP. Our analysis of flow past a half-ellipse shows that overall the MaxEP is a good predictor of the equilibrium states but, in the special case of the half-ellipse with aspect ratio much greater than unity, the MaxEP is replaced by the Min-MaxEP, at higher Reynolds numbers when inertial effects come into play. Experiments in sedimentation tanks and with hinged bodies in a flow tank confirm these calculations.

Entropy equilibrium equation and dynamic entropy production in environment liquid

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

The entropy equilibrium equation is the basis of the nonequilibrium state thermodynamics. But the internal energy implies the kinetic energy of the fluid micelle relative to mass center in the classical entropy equilibrium equation at present. This internal energy is not the mean kinetic energy of molecular movement in thermodynamics. Here a modified entropy equilibrium equation is deduced, based on the concept that the internal energy is just the mean kinetic energy of the molecular movement. A dynamic entropy production is introduced into the entropy equilibrium equation to describe the dynamic process distinctly. This modified entropy equilibrium equation can describe not only the entropy variation of the irreversible processes but also the reversible processes in a thermodynamic system. It is more reasonable and suitable for wider applications.

Brownian dynamics simulations of an order-disorder transition in sheared sterically stabilized colloidal suspensions

International Nuclear Information System (INIS)

Rigos, A.A.; Wilemski, G.

1992-01-01

The shear thinning behavior of a sterically stabilized nonaqueous colloidal suspension was investigated using nonequilibrium Brownian dynamics simulations of systems with 108 and 256 particles. At a volume fraction of 0.4, the suspension is thixotropic: it has a reversible shear thinning transition from a disordered state to an ordered, lamellar state with triangularly packed strings of particles. The time scale for the transition is set by the free particle diffusion constant. For the smaller system, the transition occurs gradually with increasing shear rate. For the larger system, the transition is sharp and discontinuous shear thinning is found. 34 refs., 9 figs., 1 tab

Assessment of drug salt release from solutions, suspensions and in situ suspensions using a rotating dialysis cell

DEFF Research Database (Denmark)

Parshad, Henrik; Frydenvang, Karla; Liljefors, Tommy

2003-01-01

buffer is used as release media. Generally, the initial release of the drug salt from in situ suspensions occurred faster as compared to conventional suspensions, probably due to incomplete precipitation of the drug salt, and hence formation of supersaturated solutions where the rate of release......A rotating dialysis cell consisting of a small (10 ml) and a large compartment (1000 ml) was used to study the release of drug salt (bupivacaine 9-anthracene carboxylate) from (i). solutions, (ii). suspensions and (iii). in situ formed suspensions. Initial release experiments from suspensions...... indicated that the release of drug salt in deionized water was predominantly limited by the diffusion across the membrane whereas it is essentially dissolution rate controlled in 0.05 M phosphate buffer (pH 7.40). Thus, the in vitro model appears to have a potential in formulation screening when phosphate...

Non-equilibrium coherence dynamics in one-dimensional Bose gases.

Science.gov (United States)

Hofferberth, S; Lesanovsky, I; Fischer, B; Schumm, T; Schmiedmayer, J

2007-09-20

Low-dimensional systems provide beautiful examples of many-body quantum physics. For one-dimensional (1D) systems, the Luttinger liquid approach provides insight into universal properties. Much is known of the equilibrium state, both in the weakly and strongly interacting regimes. However, it remains a challenge to probe the dynamics by which this equilibrium state is reached. Here we present a direct experimental study of the coherence dynamics in both isolated and coupled degenerate 1D Bose gases. Dynamic splitting is used to create two 1D systems in a phase coherent state. The time evolution of the coherence is revealed through local phase shifts of the subsequently observed interference patterns. Completely isolated 1D Bose gases are observed to exhibit universal sub-exponential coherence decay, in excellent agreement with recent predictions. For two coupled 1D Bose gases, the coherence factor is observed to approach a non-zero equilibrium value, as predicted by a Bogoliubov approach. This coupled-system decay to finite coherence is the matter wave equivalent of phase-locking two lasers by injection. The non-equilibrium dynamics of superfluids has an important role in a wide range of physical systems, such as superconductors, quantum Hall systems, superfluid helium and spin systems. Our experiments studying coherence dynamics show that 1D Bose gases are ideally suited for investigating this class of phenomena.

Modeling of the equilibrium of a tokamak plasma

International Nuclear Information System (INIS)

Grandgirard, V.

1999-12-01

The simulation and the control of a plasma discharge in a tokamak require an efficient and accurate solving of the equilibrium because this equilibrium needs to be calculated again every microsecond to simulate discharges that can last up to 1000 seconds. The purpose of this thesis is to propose numerical methods in order to calculate these equilibrium with acceptable computer time and memory size. Chapter 1 deals with hydrodynamics equation and sets up the problem. Chapter 2 gives a method to take into account the boundary conditions. Chapter 3 is dedicated to the optimization of the inversion of the system matrix. This matrix being quasi-symmetric, the Woodbury method combined with Cholesky method has been used. This direct method has been compared with 2 iterative methods: GMRES (generalized minimal residual) and BCG (bi-conjugate gradient). The 2 last chapters study the control of the plasma equilibrium, this work is presented in the formalism of the optimized control of distributed systems and leads to non-linear equations of state and quadratic functionals that are solved numerically by a quadratic sequential method. This method is based on the replacement of the initial problem with a series of control problems involving linear equations of state. (A.C.)

Molecular equilibrium with condensation

International Nuclear Information System (INIS)

Sharp, C.M.; Huebner, W.F.

1990-01-01

Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated. 18 refs

Stability of equilibrium states in finite samples of smectic C* liquid crystals

Energy Technology Data Exchange (ETDEWEB)

Stewart, I W [Department of Mathematics, University of Strathclyde, Livingstone Tower, 26 Richmond Street, Glasgow G1 1XH (United Kingdom)

2005-03-04

Equilibrium solutions for a sample of ferroelectric smectic C (SmC*) liquid crystal in the 'bookshelf' geometry under the influence of a tilted electric field will be presented. A linear stability criterion is identified and used to confirm stability for typical materials possessing either positive or negative dielectric anisotropy. The theoretical response times for perturbations to the equilibrium solutions are calculated numerically and found to be consistent with estimates for response times in ferroelectric smectic C liquid crystals reported elsewhere in the literature for non-tilted fields.

Explicit integration of extremely stiff reaction networks: partial equilibrium methods

International Nuclear Information System (INIS)

Guidry, M W; Hix, W R; Billings, J J

2013-01-01

In two preceding papers (Guidry et al 2013 Comput. Sci. Disc. 6 015001 and Guidry and Harris 2013 Comput. Sci. Disc. 6 015002), we have shown that when reaction networks are well removed from equilibrium, explicit asymptotic and quasi-steady-state approximations can give algebraically stabilized integration schemes that rival standard implicit methods in accuracy and speed for extremely stiff systems. However, we also showed that these explicit methods remain accurate but are no longer competitive in speed as the network approaches equilibrium. In this paper, we analyze this failure and show that it is associated with the presence of fast equilibration timescales that neither asymptotic nor quasi-steady-state approximations are able to remove efficiently from the numerical integration. Based on this understanding, we develop a partial equilibrium method to deal effectively with the approach to equilibrium and show that explicit asymptotic methods, combined with the new partial equilibrium methods, give an integration scheme that can plausibly deal with the stiffest networks, even in the approach to equilibrium, with accuracy and speed competitive with that of implicit methods. Thus we demonstrate that such explicit methods may offer alternatives to implicit integration of even extremely stiff systems and that these methods may permit integration of much larger networks than have been possible before in a number of fields. (paper)

Chaotic and steady state behaviour of a nonlinear controlled gyro subjected to harmonic disturbances

International Nuclear Information System (INIS)

Perez Polo, Manuel F.; Perez Molina, Manuel

2007-01-01

Chaotic and steady state motions of a nonlinear controlled gimbals suspension gyro used to stabilize an external body are studied in this paper. The equations of the gyro without nonlinear control are deduced from the Euler-Lagrange equations by using the nutation theory. The equations of the system show that a cyclic variable appears. Its elimination allows us to find an auxiliary nonlinear system from which it is possible to deduce a nonlinear control law in order to obtain a desired equilibrium point. From the analysis of the nonlinear control law it is possible to show that due to both harmonic disturbances in the platform of the gyro and in the body to stabilize, regular and chaotic motions can appear. The chaotic motion is researched by means of chaos maps, bifurcation diagrams, sensitivity to initial conditions, Lyapunov exponents and Fourier spectrum density. The transition from chaotic to steady state motion by eliminating the harmonic disturbances from the modification of the initial nonlinear control law is also researched. Next, the paper shows how to use the chaotic motion in order to obtain small input signals so that the desired equilibrium state of the gyro can be reached. The developed methodology and its compared performance are evaluated through analytical methods and numerical simulations

Chaotic and steady state behaviour of a nonlinear controlled gyro subjected to harmonic disturbances

Energy Technology Data Exchange (ETDEWEB)

Perez Polo, Manuel F. [Department of Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, Escuela Politecnica Superior, Campus de San Vicente, 03071 Alicante (Spain)]. E-mail: manolo@dfists.ua.es; Perez Molina, Manuel [Facultad de Ciencias Matematicas, Universidad Nacional de Educacion a Distancia, UNED, C/Boyero 12-1A, Alicante 03007 (Spain)]. E-mail: ma_perez_m@hotmail.com

2007-07-15

Chaotic and steady state motions of a nonlinear controlled gimbals suspension gyro used to stabilize an external body are studied in this paper. The equations of the gyro without nonlinear control are deduced from the Euler-Lagrange equations by using the nutation theory. The equations of the system show that a cyclic variable appears. Its elimination allows us to find an auxiliary nonlinear system from which it is possible to deduce a nonlinear control law in order to obtain a desired equilibrium point. From the analysis of the nonlinear control law it is possible to show that due to both harmonic disturbances in the platform of the gyro and in the body to stabilize, regular and chaotic motions can appear. The chaotic motion is researched by means of chaos maps, bifurcation diagrams, sensitivity to initial conditions, Lyapunov exponents and Fourier spectrum density. The transition from chaotic to steady state motion by eliminating the harmonic disturbances from the modification of the initial nonlinear control law is also researched. Next, the paper shows how to use the chaotic motion in order to obtain small input signals so that the desired equilibrium state of the gyro can be reached. The developed methodology and its compared performance are evaluated through analytical methods and numerical simulations.

Naratriptan hydrochloride in extemporaneosly compounded oral suspensions.

Science.gov (United States)

Zhang, Y P; Trissel, L A; Fox, J L

2000-01-01

The purpose of this study was to determine the pharmaceutical acceptability and chemical stability of naratriptan hydrochloride in three extemporaneously compounded suspension formulations. The naratriptan-hydrochloride oral suspensions were prepared from 2.5-mg commercial tablets yielding a nominal naratriptan concentration of 0.5 mg/mL. The suspension vehicles selected for testing were Syrpalta, an equal-parts mixture of Ora-Plus and Ora-Sweet, and an equal-parts mixture of Ora-Plus and Ora-Sweet SF. The tablets were crushed and thoroughly triturated to a fine powder using a porcelain mortar and pestle. The powder was incorporated into a portion of the Syrpalta or Ora-Plus suspension vehicle and mixed until homogeneous. The mixtures were then brought to volume with Syrpalta, Ora-Sweet or Ora-Sweet SF, as appropriate. The suspensions were packaged in amber, plastic, screw-cap prescription bottles and stored at 23 deg C for seven days and 4 deg C for 90 days. An adequate suspension was never achieved in Syrpalta. The crushed-tablet powder did not produce a uniformly dispersed mixture and exhibited clumping and a high rate of sedimentation. A distinct layer of the solid tablet material settled immediately after shaking. Over the next four hours, a densely packed, yellow, caked layer formed at the bottom of the containers, making resuspension difficult. During storage, the caking became worse. Chemical analysis was not performed. The Ora-Plus and Ora-Sweet or Ora-Sweet SF suspensions had a slight greenish cast and were resuspended without difficulty by shaking for approximately ten seconds, yielding easily poured and homogeneous mixtures throughout the study. Visible settling and layering did not begin for four hours with the Ora-Sweet suspension and 24 hours for the Ora-Sweet SF suspension. High pressure liquid chromatographic analysis found that the naratriptan concentration in both suspension-vehicle combinations exhibited little or no loss for seven days at 23

Sky-Hook Control and Kalman Filtering in Nonlinear Model of Tracked Vehicle Suspension System

Directory of Open Access Journals (Sweden)

Jurkiewicz Andrzej

2017-09-01

Full Text Available The essence of the undertaken topic is application of the continuous sky-hook control strategy and the Extended Kalman Filter as the state observer in the 2S1 tracked vehicle suspension system. The half-car model of this suspension system consists of seven logarithmic spiral springs and two magnetorheological dampers which has been described by the Bingham model. The applied continuous sky-hook control strategy considers nonlinear stiffness characteristic of the logarithmic spiral springs. The control is determined on estimates generated by the Extended Kalman Filter. Improve of ride comfort is verified by comparing simulation results, under the same driving conditions, of controlled and passive vehicle suspension systems.

Adiabatic out-of-equilibrium solutions to the Boltzmann equation in warm inflation

Science.gov (United States)

Bastero-Gil, Mar; Berera, Arjun; Ramos, Rudnei O.; Rosa, João G.

2018-02-01

We show that, in warm inflation, the nearly constant Hubble rate and temperature lead to an adiabatic evolution of the number density of particles interacting with the thermal bath, even if thermal equilibrium cannot be maintained. In this case, the number density is suppressed compared to the equilibrium value but the associated phase-space distribution retains approximately an equilibrium form, with a smaller amplitude and a slightly smaller effective temperature. As an application, we explicitly construct a baryogenesis mechanism during warm inflation based on the out-of-equilibrium decay of particles in such an adiabatically evolving state. We show that this generically leads to small baryon isocurvature perturbations, within the bounds set by the Planck satellite. These are correlated with the main adiabatic curvature perturbations but exhibit a distinct spectral index, which may constitute a smoking gun for baryogenesis during warm inflation. Finally, we discuss the prospects for other applications of adiabatically evolving out-of-equilibrium states.

Local equilibrium in bird flocks

Science.gov (United States)

Mora, Thierry; Walczak, Aleksandra M.; Del Castello, Lorenzo; Ginelli, Francesco; Melillo, Stefania; Parisi, Leonardo; Viale, Massimiliano; Cavagna, Andrea; Giardina, Irene

2016-12-01

The correlated motion of flocks is an example of global order emerging from local interactions. An essential difference with respect to analogous ferromagnetic systems is that flocks are active: animals move relative to each other, dynamically rearranging their interaction network. This non-equilibrium characteristic has been studied theoretically, but its impact on actual animal groups remains to be fully explored experimentally. Here, we introduce a novel dynamical inference technique, based on the principle of maximum entropy, which accommodates network rearrangements and overcomes the problem of slow experimental sampling rates. We use this method to infer the strength and range of alignment forces from data of starling flocks. We find that local bird alignment occurs on a much faster timescale than neighbour rearrangement. Accordingly, equilibrium inference, which assumes a fixed interaction network, gives results consistent with dynamical inference. We conclude that bird orientations are in a state of local quasi-equilibrium over the interaction length scale, providing firm ground for the applicability of statistical physics in certain active systems.

Heavy vehicle pitch dynamics and suspension tuning

OpenAIRE

Cao, Dongpu; Rakheja, Subhash; Su, Chun-Yi

2008-01-01

The influence of suspension tuning of passenger cars on bounce and pitch ride performance has been explored in a number of studies, while only minimal efforts have been made for establishing similar rules for heavy vehicles. This study aims to explore pitch dynamics and suspension tunings of a two-axle heavy vehicle with unconnected suspension, which could also provide valuable information for heavy vehicles with coupled suspensions. Based on a generalised pitch-plane model of a two-axle heav...

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.

Ageing in the trap model as a relaxation further away from equilibrium

International Nuclear Information System (INIS)

Bertin, Eric

2013-01-01

The ageing regime of the trap model, observed for a temperature T below the glass transition temperature T g , is a prototypical example of non-stationary out-of-equilibrium state. We characterize this state by evaluating its ‘distance to equilibrium’, defined as the Shannon entropy difference ΔS (in absolute value) between the non-equilibrium state and the equilibrium state with the same energy. We consider the time evolution of ΔS and show that, rather unexpectedly, ΔS(t) continuously increases in the ageing regime, if the number of traps is infinite, meaning that the ‘distance to equilibrium’ increases instead of decreasing in the relaxation process. For a finite number N of traps, ΔS(t) exhibits a maximum value before eventually converging to zero when equilibrium is reached. The time t* at which the maximum is reached however scales in a non-standard way as t * ∼N T g /2T , while the equilibration time scales as τ eq ∼N T g /T . In addition, the curves ΔS(t) for different N are found to rescale as ln t/ln t*, instead of the more familiar scaling t/t*. (paper)

Dynamical Cooper pairing in non-equilibrium electron-phonon systems

Energy Technology Data Exchange (ETDEWEB)

Knap, Michael [Technical University of Munich (Germany); Harvard University (United States); Babadi, Mehrtash; Refael, Gil [Caltech (United States); Martin, Ivar [Argonne National Laboratory (United States); Demler, Eugene [Harvard University (United States)

2016-07-01

Ultrafast laser pulses have been used to manipulate complex quantum materials and to induce dynamical phase transitions. One of the most striking examples is the transient enhancement of superconductivity in several classes of materials upon irradiating them with high intensity pulses of terahertz light. Motivated by these experiments we analyze the Cooper pairing instabilities in non-equilibrium electron-phonon systems. We demonstrate that the light induced non-equilibrium state of phonons results in a simultaneous increase of the superconducting coupling constant and the electron scattering. We analyze the competition between these effects and show that in a broad range of parameters the dynamic enhancement of Cooper pair formation dominates over the increase in the scattering rate. This opens the possibility of transient light induced superconductivity at temperatures that are considerably higher than the equilibrium transition temperatures. Our results pave new pathways for engineering high-temperature light-induced superconducting states.

Thermal equilibrium control by frequent bang-bang modulation.

Science.gov (United States)

Yang, Cheng-Xi; Wang, Xiang-Bin

2010-05-01

In this paper, we investigate the non-Markovian heat transfer between a weakly damped harmonic oscillator (system) and a thermal bath. When the system is initially in a thermal state and not correlated with the environment, the mean energy of the system always first increases, then oscillates, and finally reaches equilibrium with the bath, no matter what the initial temperature of the system is. Moreover, the heat transfer between the system and the bath can be controlled by fast bang-bang modulation. This modulation does work on the system, and temporarily inverts the direction of heat flow. In this case, the common sense that heat always transfers from hot to cold does not hold any more. At the long time scale, a new dynamic equilibrium is established between the system and the bath. At this equilibrium, the energy of the system can be either higher or lower than its normal equilibrium value. A comprehensive analysis of the relationship between the dynamic equilibrium and the parameters of the modulation as well as the environment is presented.

Non-equilibrium phase transitions in complex plasma

International Nuclear Information System (INIS)

Suetterlin, K R; Raeth, C; Ivlev, A V; Thomas, H M; Khrapak, S; Zhdanov, S; Rubin-Zuzic, M; Morfill, G E; Wysocki, A; Loewen, H; Goedheer, W J; Fortov, V E; Lipaev, A M; Molotkov, V I; Petrov, O F

2010-01-01

Complex plasma being the 'plasma state of soft matter' is especially suitable for investigations of non-equilibrium phase transitions. Non-equilibrium phase transitions can manifest in dissipative structures or self-organization. Two specific examples are lane formation and phase separation. Using the permanent microgravity laboratory PK-3 Plus, operating onboard the International Space Station, we performed unique experiments with binary mixtures of complex plasmas that showed both lane formation and phase separation. These observations have been augmented by comprehensive numerical and theoretical studies. In this paper we present an overview of our most important results. In addition we put our results in context with research of complex plasmas, binary systems and non-equilibrium phase transitions. Necessary and promising future complex plasma experiments on phase separation and lane formation are briefly discussed.

Solution or suspension - Does it matter for lipid based systems? In vivo studies of chase dosing lipid vehicles with aqueous suspensions of a poorly soluble drug.

Science.gov (United States)

Larsen, A T; Holm, R; Müllertz, A

2017-08-01

In this study, the potential of co-administering an aqueous suspension with a placebo lipid vehicle, i.e. chase dosing, was investigated in rats relative to the aqueous suspension alone or a solution of the drug in the lipid vehicle. The lipid investigated in the present study was Labrafil M2125CS and three evaluated poorly soluble model compounds, danazol, cinnarizine and halofantrine. For cinnarizine and danazol the oral bioavailability in rats after chase dosing or dosing the compound dissolved in Labrafil M21515CS was similar and significantly higher than for the aqueous suspension. For halofantrine the chase dosed group had a tendency towards a low bioavailability relative to the Labrafil M2125CS solution, but still a significant higher bioavailability relative to the aqueous suspension. This could be due to factors such as a slower dissolution rate in the intestinal phase of halofantrine or a lower solubility in the colloidal structures formed during digestion, but other mechanisms may also be involved. The study thereby supported the potential of chase dosing as a potential dosing regimen in situations where it is beneficial to have a drug in the solid state, e.g. due to chemical stability issues in the lipid vehicle. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of cell suspensions from solid tumors

International Nuclear Information System (INIS)

Pallavicini, M.

1985-01-01

The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with different degrees of clonogenicity, as well as altered biochemical features, such as loss of cellular proteins, surface antigens, nucleotide pools, etc. The quality of the cell suspension can be judged by the degree of cell clumping and level of cellular debris, both of which impact on flow cytometric measurements and studies in which the number of cells be known accurately. Finally, if the data measured on the cells in suspension are to be extrapolated to phenomena occurring in the tumor in situ, it is desirable that the cells in suspension are representative of those in the solid tumor in vivo. This report compares characteristics of tumor cell suspensions obtained by different types of selected disaggregation methods. 33 refs., 2 figs., 4 tabs

Energy flow in non-equilibrium conformal field theory

Science.gov (United States)

Bernard, Denis; Doyon, Benjamin

2012-09-01

We study the energy current and its fluctuations in quantum gapless 1d systems far from equilibrium modeled by conformal field theory, where two separated halves are prepared at distinct temperatures and glued together at a point contact. We prove that these systems converge towards steady states, and give a general description of such non-equilibrium steady states in terms of quantum field theory data. We compute the large deviation function, also called the full counting statistics, of energy transfer through the contact. These are universal and satisfy fluctuation relations. We provide a simple representation of these quantum fluctuations in terms of classical Poisson processes whose intensities are proportional to Boltzmann weights.

Analysis of plasma equilibrium based on orbit-driven current density profile in steady-state plasma on QUEST

Energy Technology Data Exchange (ETDEWEB)

Nakamura, K., E-mail: nakamura@triam.kyushu-u.ac.jp [RIAM, Kyushu University, Kasuga 816-8580 (Japan); Alam, M.M. [IGSES, Kyushu University, Kasuga 816-8580 (Japan); Jiang, Y.Z. [Tsinghua University, Beijing 100084 (China); Mitarai, O. [Tokai University, Kumamoto 862-8652 (Japan); Kurihara, K.; Kawamata, Y.; Sueoka, M.; Takechi, M. [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Hasegawa, M.; Tokunaga, K.; Araki, K.; Zushi, H.; Hanada, K.; Fujisawa, A.; Idei, H.; Nagashima, Y.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Nagata, T. [RIAM, Kyushu University, Kasuga 816-8580 (Japan); and others

2016-11-01

Highlights: • High energy particle guiding center orbit is calculated as a contour plot of conserved variable. • Current density profile is analyzed based on the orbit-driven current. • Plasma equilibrium is reconstructed by considering the hollow current profile. - Abstract: In the present RF-driven (ECCD) steady-state plasma on QUEST (B{sub t} = 0.25 T, R = 0.68 m, a = 0.40 m), plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to plasma current fitting (PCF) method. We consider that the current in the open magnetic surface is due to orbit-driven current by high-energy particles in RF-driven plasma. So based on the analysis of current density profile based on the orbit-driven current, plasma equilibrium is to be calculated. We calculated high energy particles guiding center orbits as a contour plot of conserved variable in Hamiltonian formulation and considered particles initial position with different levels of energy and pitch angles that satisfy resonance condition. Then the profile of orbit-driven current is estimated by multiplying the particle density on the resonance surface and the velocity on the orbits. This analysis shows negative current near the magnetic axis and hollow current profile is expected even if pressure driven current is considered. Considering the hollow current profile shifted toward the low-field region, the equilibrium is fitted by J-EFIT coded by MATLAB.

Simulations of NMR pulse sequences during equilibrium and non-equilibrium chemical exchange

International Nuclear Information System (INIS)

Helgstrand, Magnus; Haerd, Torleif; Allard, Peter

2000-01-01

The McConnell equations combine the differential equations for a simple two-state chemical exchange process with the Bloch differential equations for a classical description of the behavior of nuclear spins in a magnetic field. This equation system provides a useful starting point for the analysis of slow, intermediate and fast chemical exchange studied using a variety of NMR experiments. The McConnell equations are in the mathematical form of an inhomogeneous system of first-order differential equations. Here we rewrite the McConnell equations in a homogeneous form in order to facilitate fast and simple numerical calculation of the solution to the equation system. The McConnell equations can only treat equilibrium chemical exchange. We therefore also present a homogeneous equation system that can handle both equilibrium and non-equilibrium chemical processes correctly, as long as the kinetics is of first-order. Finally, the same method of rewriting the inhomogeneous form of the McConnell equations into a homogeneous form is applied to a quantum mechanical treatment of a spin system in chemical exchange. In order to illustrate the homogeneous McConnell equations, we have simulated pulse sequences useful for measuring exchange rates in slow, intermediate and fast chemical exchange processes. A stopped-flow NMR experiment was simulated using the equations for non-equilibrium chemical exchange. The quantum mechanical treatment was tested by the simulation of a sensitivity enhanced 15 N-HSQC with pulsed field gradients during slow chemical exchange and by the simulation of the transfer efficiency of a two-dimensional heteronuclear cross-polarization based experiment as a function of both chemical shift difference and exchange rate constants

Low-resolution simulations of vesicle suspensions in 2D

Science.gov (United States)

Kabacaoğlu, Gökberk; Quaife, Bryan; Biros, George

2018-03-01

Vesicle suspensions appear in many biological and industrial applications. These suspensions are characterized by rich and complex dynamics of vesicles due to their interaction with the bulk fluid, and their large deformations and nonlinear elastic properties. Many existing state-of-the-art numerical schemes can resolve such complex vesicle flows. However, even when using provably optimal algorithms, these simulations can be computationally expensive, especially for suspensions with a large number of vesicles. These high computational costs can limit the use of simulations for parameter exploration, optimization, or uncertainty quantification. One way to reduce the cost is to use low-resolution discretizations in space and time. However, it is well-known that simply reducing the resolution results in vesicle collisions, numerical instabilities, and often in erroneous results. In this paper, we investigate the effect of a number of algorithmic empirical fixes (which are commonly used by many groups) in an attempt to make low-resolution simulations more stable and more predictive. Based on our empirical studies for a number of flow configurations, we propose a scheme that attempts to integrate these fixes in a systematic way. This low-resolution scheme is an extension of our previous work [51,53]. Our low-resolution correction algorithms (LRCA) include anti-aliasing and membrane reparametrization for avoiding spurious oscillations in vesicles' membranes, adaptive time stepping and a repulsion force for handling vesicle collisions and, correction of vesicles' area and arc-length for maintaining physical vesicle shapes. We perform a systematic error analysis by comparing the low-resolution simulations of dilute and dense suspensions with their high-fidelity, fully resolved, counterparts. We observe that the LRCA enables both efficient and statistically accurate low-resolution simulations of vesicle suspensions, while it can be 10× to 100× faster.

Note: Local thermal conductivities from boundary driven non-equilibrium molecular dynamics simulations

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

13 CFR 120.660 - Suspension or revocation.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Suspension or revocation. 120.660 Section 120.660 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Suspension Or Revocation of Participant in Secondary Market § 120.660 Suspension or revocation. (a...

Clay-cement suspensions - rheological and functional properties

Science.gov (United States)

Wojcik, L.; Izak, P.; Mastalska-Poplawska, J.; Gajek, M.

2017-01-01

The piping erosion in soil is highly unexpected in civil engineering. Elimination of such damages is difficult, expensive and time-consuming. One of the possibility is the grouting method. This method is still developed into direction of process automation as well as other useful properties of suspensions. Main way of modernization of the grouting method is connected it with rheology of injection and eventuality of fitting them to specific problems conditions. Very popular and useful became binders based on modified clays (clay-cement suspensions). Important principle of efficiency of the grouting method is using of time-dependent pseudothixotropic properties of the clay-cement suspensions. The pseudo-rheounstability aspect of the suspensions properties should be dedicated and fitted to dynamic changes of soil conditions destructions. Whole process of the modification of the suspension rheology is stimulated by the specific agents. This article contains a description of practical aspects of the rheological parameters managing of the clay-cement suspensions, dedicated to the building damages, hydrotechnic constructions etc.

Non-equilibrium plasma kinetics of reacting CO: an improved state to state approach

Science.gov (United States)

Pietanza, L. D.; Colonna, G.; Capitelli, M.

2017-12-01

Non-equilibrium plasma kinetics of reacting CO for conditions typically met in microwave discharges have been developed based on the coupling of excited state kinetics and the Boltzmann equation for the electron energy distribution function (EEDF). Particular attention is given to the insertion in the vibrational kinetics of a complete set of electron molecule resonant processes linking the whole vibrational ladder of the CO molecule, as well as to the role of Boudouard reaction, i.e. the process of forming CO2 by two vibrationally excited CO molecules, in shaping the vibrational distribution of CO and promoting reaction channels assisted by vibrational excitation (pure vibrational mechanisms, PVM). PVM mechanisms can become competitive with electron impact dissociation processes (DEM) in the activation of CO. A case study reproducing the conditions of a microwave discharge has been considered following the coupled kinetics also in the post discharge conditions. Results include the evolution of EEDF in discharge and post discharge conditions highlighting the role of superelastic vibrational and electronic collisions in shaping the EEDF. Moreover, PVM rate coefficients and DEM ones are studied as a function of gas temperature, showing a non-Arrhenius behavior, i.e. the rate coefficients increase with decreasing gas temperature as a result of a vibrational-vibrational (V-V) pumping up mechanism able to form plateaux in the vibrational distribution function. The accuracy of the results is discussed in particular in connection to the present knowledge of the activation energy of the Boudouard process.

Time Varying Behavior of the Loudspeaker Suspension

DEFF Research Database (Denmark)

Pedersen, Bo Rohde; Agerkvist, Finn T.

2007-01-01

The suspension part of the electrodynamic loudspeaker is often modelled as a simple linear spring with viscous damping, however the dynamic behaviour of the suspension is much more complicated than predicted by such a simple model. At higher levels the compliance becomes non-linear and often chan...... changes during excitation at high levels. This paper investigates how the compliance of the suspension depends on the excitation, i.e. level and frequency content. The measurements are compared with other known measurement methods of the suspension....

Study on kinematic and compliance test of suspension

Science.gov (United States)

Jing, Lixin; Wu, Liguang; Li, Xuepeng; Zhang, Yu

2017-09-01

Chassis performance development is a major difficulty in vehicle research and development, which is the main factor restricting the independent development of vehicles in China. These years, through a large number of studies, chassis engineers have found that the suspension K&C characteristics as a quasi-static characteristic of the suspension provides a technical route for the suspension performance R&D, and the suspension K&C test has become an important means of vehicle benchmarking, optimization and verification. However, the research on suspension K&C test is less in china, and the test conditions and setting requirements vary greatly from OEM to OEM. In this paper, the influence of different settings on the characteristics of the suspension is obtained through experiments, and the causes of the differences are analyzed; in order to fully reflect the suspension characteristics, the author recommends the appropriate test case and settings.

Pair-correlations in swimmer suspensions

Science.gov (United States)

Nambiar, Sankalp; Subramanian, Ganesh

2017-11-01

Suspensions of rear-actuated swimming microorganisms, such as E.coli, exhibit several interesting phenomena including spontaneous pattern formation above a critical concentration, novel rheological properties, shear-induced concentration banding etc. Explanations based on mean-field theory are only qualitative, since interactions between swimmers are important for typical experimental concentrations. We analytically characterize the hydrodynamic pair-interactions in a quiescent suspension of slender straight swimmers. The pair-correlation, calculated at leading order by integrating the swimmer velocity disturbances along straight trajectories, decays as 1/r2 for r >> L (L being the swimmer size). This allows us to characterize both polar and nematic correlations in an interacting swimmer suspension. In the absence of correlations, the velocity covariance asymptotes from a constant for r > L, the latter being characteristic of a suspension of non-interacting point force-dipoles. On including correlations, the slow decay of the pair-orientation correlation leads to an additional contribution to the velocity covariance that diverges logarithmically with system size.

Negative velocity fluctuations and non-equilibrium fluctuation relation for a driven high critical current vortex state.

Science.gov (United States)

Bag, Biplab; Shaw, Gorky; Banerjee, S S; Majumdar, Sayantan; Sood, A K; Grover, A K

2017-07-17

Under the influence of a constant drive the moving vortex state in 2H-NbS 2 superconductor exhibits a negative differential resistance (NDR) transition from a steady flow to an immobile state. This state possesses a high depinning current threshold ([Formula: see text]) with unconventional depinning characteristics. At currents well above [Formula: see text], the moving vortex state exhibits a multimodal velocity distribution which is characteristic of vortex flow instabilities in the NDR regime. However at lower currents which are just above [Formula: see text], the velocity distribution is non-Gaussian with a tail extending to significant negative velocity values. These unusual negative velocity events correspond to vortices drifting opposite to the driving force direction. We show that this distribution obeys the Gallavotti-Cohen Non-Equilibrium Fluctuation Relation (GC-NEFR). Just above [Formula: see text], we also find a high vortex density fluctuating driven state not obeying the conventional GC-NEFR. The GC-NEFR analysis provides a measure of an effective energy scale (E eff ) associated with the driven vortex state. The E eff corresponds to the average energy dissipated by the fluctuating vortex state above [Formula: see text]. We propose the high E eff value corresponds to the onset of high energy dynamic instabilities in this driven vortex state just above [Formula: see text].

Equilibrium and pre-equilibrium emissions in proton-induced ...

Indian Academy of Sciences (India)

necessary for the domain of fission-reactor technology for the calculation of nuclear transmutation ... tions occur in three stages: INC, pre-equilibrium and equilibrium (or compound. 344. Pramana ... In the evaporation phase of the reaction, the.

21 CFR 1301.36 - Suspension or revocation of registration; suspension of registration pending final order...

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Suspension or revocation of registration; suspension of registration pending final order; extension of registration pending final order. 1301.36... registration pending final order; extension of registration pending final order. (a) For any registration...

Failure of Local Thermal Equilibrium in Quantum Friction

Science.gov (United States)

Intravaia, F.; Behunin, R. O.; Henkel, C.; Busch, K.; Dalvit, D. A. R.

2016-09-01

Recent progress in manipulating atomic and condensed matter systems has instigated a surge of interest in nonequilibrium physics, including many-body dynamics of trapped ultracold atoms and ions, near-field radiative heat transfer, and quantum friction. Under most circumstances the complexity of such nonequilibrium systems requires a number of approximations to make theoretical descriptions tractable. In particular, it is often assumed that spatially separated components of a system thermalize with their immediate surroundings, although the global state of the system is out of equilibrium. This powerful assumption reduces the complexity of nonequilibrium systems to the local application of well-founded equilibrium concepts. While this technique appears to be consistent for the description of some phenomena, we show that it fails for quantum friction by underestimating by approximately 80% the magnitude of the drag force. Our results show that the correlations among the components of driven, but steady-state, quantum systems invalidate the assumption of local thermal equilibrium, calling for a critical reexamination of this approach for describing the physics of nonequilibrium systems.

Derivation of the chemical-equilibrium rate coefficient using scattering theory

Science.gov (United States)

Mickens, R. E.

1977-01-01

Scattering theory is applied to derive the equilibrium rate coefficient for a general homogeneous chemical reaction involving ideal gases. The reaction rate is expressed in terms of the product of a number of normalized momentum distribution functions, the product of the number of molecules with a given internal energy state, and the spin-averaged T-matrix elements. An expression for momentum distribution at equilibrium for an arbitrary molecule is presented, and the number of molecules with a given internal-energy state is represented by an expression which includes the partition function.

Disturbance observer based Takagi-Sugeno fuzzy control for an active seat suspension

Science.gov (United States)

Ning, Donghong; Sun, Shuaishuai; Zhang, Fei; Du, Haiping; Li, Weihua; Zhang, Bangji

2017-09-01

In this paper, a disturbance observer based Takagi-Sugeno (TS) fuzzy controller is proposed for an active seat suspension; both simulations and experiments have been performed verifying the performance enhancement and stability of the proposed controller. The controller incorporates closed-loop feedback control using the measured acceleration of the seat and deflection of the suspension; these two variables can be easily measured in practical applications, thus allowing the proposed controller to be robust and adaptable. A disturbance observer that can estimate the disturbance caused by friction, model simplification, and controller output error has also been used to compensate a H∞ state feedback controller. The TS fuzzy control method is applied to enhance the controller's performance by considering the variation of driver's weight during operation. The vibration of a heavy duty vehicle seat is largest in the frequency range between 2 Hz and 4 Hz, in the vertical direction; therefore, it is reasonable to focus on controlling low frequency vibration amplitudes and maintain the seat suspensions passivity at high frequency. Moreover, both the simulation and experimental results show that the active seat suspension with the proposed controller can effectively isolate unwanted vibration amplitudes below 4.5 Hz, when compared with a well-tuned passive seat suspension. The active controller has been further validated under bump and random road tests with both a 55 kg and a 70 kg loads. The bump road test demonstrated the controller has good transient response capabilities. The random road test result has been presented both in the time domain and the frequency domain. When with the above two loads, the controlled seat suspensions root-mean-square (RMS) accelerations were reduced by 45.5% and 49.5%, respectively, compared with a well-tuned passive seat suspension. The proposed active seat suspension controller has great potential and is very practical for application

Shape characteristics of equilibrium and non-equilibrium fractal clusters.

Science.gov (United States)

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

39 CFR 3001.114 - Suspension pending review.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Suspension pending review. 3001.114 Section 3001... Suspension pending review. (a) Application. Application for suspension of a determination of the Postal Service to close or consolidate any post office pending the outcome of an appeal to the Postal Regulatory...

21 CFR 520.905a - Fenbendazole suspension.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Fenbendazole suspension. 520.905a Section 520.905a... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.905a Fenbendazole suspension. (a) Specifications. Each milliliter of suspension contains 100 milligrams (mg) fenbendazole. (b...

Research on the quantum multistep theory for pre-equilibrium nuclear reaction

CERN Document Server

Su Zong Di; Abdurixit, A; Wang Shu Nuan; Li Bao Xian; Huang Zhong; Liu Jian Feng; Zhang Benai; Zhu Yao Yin; Li Zhi Wen

2002-01-01

The Feshbach-Kerman-Koonin (FKK) quantum multistep theory of the pre-equilibrium reaction is further improved and perfected. A unified description for the multistep compound (MSC) process of the pre-equilibrium reaction and the compound nucleus (CN) process of full equilibrium reaction can be presented. This formula can integrate MSC and CN theories with the optical model and Hauser-Feshbach formula, and can get self-consistent expression. In multistep direct (MSD) process of the pre-equilibrium reaction, the mu-step cross section can be expressed by the convolution of mu one-step cross section. And the one step cross section for continuum can be written as the product of an averaged DWBA matrix element and the state density. For calculating the multistep direct reaction cross section, two methods, the state densities and full microscopic model, are used and compared. Some typical experiments are analyzed by using the work mentioned above. The calculated results are reasonable and in good agreement with the e...

Kinetic attractor phase diagrams of active nematic suspensions: the dilute regime.

Science.gov (United States)

Forest, M Gregory; Wang, Qi; Zhou, Ruhai

2015-08-28

state, consisting of discrete 1d banded or 2d cellular patterns depending on nanorod volume fraction. Increasing activation strength further induces a sequence of attractor bifurcations, including oscillations superimposed on the 1d and 2d stationary patterns, a uniform translational motion of 1d and 2d oscillating patterns, and periodic switching between 1d and 2d patterns. These results imply that active macromolecular suspensions are capable of long-range spatial and dynamic organization at isotropic equilibrium concentrations, provided particle-scale activation is sufficiently strong.

Gated equilibrium bloodpool scintigraphy

International Nuclear Information System (INIS)

Reinders Folmer, S.C.C.

1981-01-01

This thesis deals with the clinical applications of gated equilibrium bloodpool scintigraphy, performed with either a gamma camera or a portable detector system, the nuclear stethoscope. The main goal has been to define the value and limitations of noninvasive measurements of left ventricular ejection fraction as a parameter of cardiac performance in various disease states, both for diagnostic purposes as well as during follow-up after medical or surgical intervention. Secondly, it was attempted to extend the use of the equilibrium bloodpool techniques beyond the calculation of ejection fraction alone by considering the feasibility to determine ventricular volumes and by including the possibility of quantifying valvular regurgitation. In both cases, it has been tried to broaden the perspective of the observations by comparing them with results of other, invasive and non-invasive, procedures, in particular cardiac catheterization, M-mode echocardiography and myocardial perfusion scintigraphy. (Auth.)

Nonlinear Robust Observer-Based Fault Detection for Networked Suspension Control System of Maglev Train

Directory of Open Access Journals (Sweden)

Yun Li

2013-01-01

Full Text Available A fault detection approach based on nonlinear robust observer is designed for the networked suspension control system of Maglev train with random induced time delay. First, considering random bounded time-delay and external disturbance, the nonlinear model of the networked suspension control system is established. Then, a nonlinear robust observer is designed using the input of the suspension gap. And the estimate error is proved to be bounded with arbitrary precision by adopting an appropriate parameter. When sensor faults happen, the residual between the real states and the observer outputs indicates which kind of sensor failures occurs. Finally, simulation results using the actual parameters of CMS-04 maglev train indicate that the proposed method is effective for maglev train.

22 CFR 126.2 - Temporary suspension or modification of this subchapter.

Science.gov (United States)

2010-04-01

... subchapter. 126.2 Section 126.2 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS GENERAL POLICIES AND PROVISIONS § 126.2 Temporary suspension or modification of this subchapter. The Deputy Assistant Secretary for Defense Trade Controls or the Managing Director, Directorate of...

Diffusion kinetics and spinodal decay of quasi-equilibrium solid solutions

International Nuclear Information System (INIS)

Zakharov, M.A.

2000-01-01

Phenomenological theory for rearrangement of solid solutions with the hierarchy of the component atomic mobilities is elaborated in the approximation of the local equilibrium. The hydrodynamic stage of the evolution of these solutions is studied as a sequence of quasi-equilibrium states characterized by implementation of some conditions of the total equilibrium. On the basis of separation of fast and slow constituents of diffusion and on the basis of the method of reduced description one derived equation for evolution of separations of fast components in quasi-equilibrium solid solutions at the arbitrary stages of rearrangement in terms of the generalized lattice model taking account of the proper volumes of the components. The conditions of the stability of quasi-equilibrium solutions to the spinodal decomposition are determined and the equations of metastability boundaries of such systems are derived [ru

X-ray scattering studies of non-equilibrium ordering processes

International Nuclear Information System (INIS)

Nagler, S.E.

1990-01-01

We report on the progress of our project entitled ''X-ray Scattering of Non-Equilibrium Ordering Processes.'' During the past year we have made the first synchrotron measurements of ordering in Cu 3 Au have revealed the presence of an intermediate, non-equilibrium ordered state. Preliminary work involving x-ray magnetic scattering has been carried out. Work is continuing in these areas as well as on related problems. 5 refs

Non-local thermodynamic equilibrium effects on isentropic coefficient in argon and helium thermal plasmas

International Nuclear Information System (INIS)

Sharma, Rohit; Singh, Kuldip

2014-01-01

In the present work, two cases of thermal plasma have been considered; the ground state plasma in which all the atoms and ions are assumed to be in the ground state and the excited state plasma in which atoms and ions are distributed over various possible excited states. The variation of Zγ, frozen isentropic coefficient and the isentropic coefficient with degree of ionization and non-equilibrium parameter θ(= T e /T h ) has been investigated for the ground and excited state helium and argon plasmas at pressures 1 atm, 10 atm, and 100 atm in the temperature range from 6000 K to 60 000 K. For a given value of non-equilibrium parameter, the relationship of Zγ with degree of ionization does not show any dependence on electronically excited states in helium plasma whereas in case of argon plasma this dependence is not appreciable till degree of ionization approaches 2. The minima of frozen isentropic coefficient shifts toward lower temperature with increase of non-equilibrium parameter for both the helium and argon plasmas. The lowering of non-equilibrium parameter decreases the frozen isentropic coefficient more emphatically in helium plasma at high pressures in comparison to argon plasma. The increase of pressure slightly reduces the ionization range over which isentropic coefficient almost remains constant and it does not affect appreciably the dependence of isentropic coefficient on non-equilibrium parameter

What Can Reinforcement Learning Teach Us About Non-Equilibrium Quantum Dynamics

Science.gov (United States)

Bukov, Marin; Day, Alexandre; Sels, Dries; Weinberg, Phillip; Polkovnikov, Anatoli; Mehta, Pankaj

Equilibrium thermodynamics and statistical physics are the building blocks of modern science and technology. Yet, our understanding of thermodynamic processes away from equilibrium is largely missing. In this talk, I will reveal the potential of what artificial intelligence can teach us about the complex behaviour of non-equilibrium systems. Specifically, I will discuss the problem of finding optimal drive protocols to prepare a desired target state in quantum mechanical systems by applying ideas from Reinforcement Learning [one can think of Reinforcement Learning as the study of how an agent (e.g. a robot) can learn and perfect a given policy through interactions with an environment.]. The driving protocols learnt by our agent suggest that the non-equilibrium world features possibilities easily defying intuition based on equilibrium physics.

The Stability of Tidal Equilibrium for Hierarchical Star-Planet-Moon Systems

Science.gov (United States)

Adams, Fred C.

2018-04-01

Motivated by the current search for exomoons, this talk considers the stability of tidal equilibrium for hierarchical three-body systems containing a star, a planet, and a moon. In this treatment, the energy and angular momentum budgets include contributions from the planetary orbit, lunar orbit, stellar spin, planetary spin, and lunar spin. The goal is to determine the optimized energy state of the system subject to the constraint of constant angular momentum. Due to the lack of a closed form solution for the full three-body problem, however, we must use use an approximate description of the orbits. We first consider the Keplerian limit and find that the critical energy states are saddle points, rather than minima, so that these hierarchical systems have no stable tidal equilibrium states. We then generalize the calculation so that the lunar orbit is described by a time-averaged version of the circular restricted three-body problem. In this latter case, the critical energy state is a shallow minimum, so that a tidal equilibrium state exists. In both cases, however, the lunar orbit for the critical point lies outside the boundary (roughly half the Hill radius) where (previous) numerical simulations indicate dynamical instability.

A Tightly Coupled Non-Equilibrium Magneto-Hydrodynamic Model for Inductively Coupled RF Plasmas

Science.gov (United States)

2016-02-29

development a tightly coupled magneto-hydrodynamic model for Inductively Coupled Radio- Frequency (RF) Plasmas. Non Local Thermodynamic Equilibrium (NLTE...for Inductively Coupled Radio-Frequency (RF) Plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State...Inductively Coupled Plasma (ICP) torches have wide range of possible applications which include deposition of metal coatings, synthesis of ultra-fine powders

On the Benefits of Semi-Active Suspensions with Inerters

Directory of Open Access Journals (Sweden)

Xin-Jie Zhang

2012-01-01

Full Text Available Inerters have become a hot topic in recent years especially in vehicle, train, building suspension systems, etc. Eight different layouts of suspensions were analyzed with a quarter-car model in this paper. Dimensionless root mean square (RMS responses of the sprung mass vertical acceleration, the suspension travel, and the tire deflection are derived which were used to evaluate the performance of the quarter-car model. The behaviour of semi-active suspensions with inerters using Groundhook, Skyhook, and Hybrid control has been evaluated and compared to the performance of passive suspensions with inerters. Sensitivity analysis was applied to the development of a high performance semi-active suspension with an inerter. Numerical simulations indicate that a semi-active suspension with an inerter has much better performance than the passive suspension with an inerter, especially with the Hybrid control method, which has the best compromise between comfort and road holding quality.

Equilibrium and non-equilibrium conformations of peptides in lipid bilayers.

Science.gov (United States)

Boden, N; Cheng, Y; Knowles, P F

1997-04-22

A synthetic, hydrophobic, 27-amino-acid-residue peptide 'K27', modelled on the trans-membrane domain of the slow voltage-gated potassium channel, IsK, has been incorporated into a lipid bilayer and its conformational properties studied using FT-IR spectroscopy. The conformation following reconstitution is found to be dependent on the nature of the solvent employed. When the reconstitution is conducted by solvent evaporation from a methanol solution, aggregates comprised of beta-strands are stabilised and their concentration is essentially invariant with time. By contrast, when trifluoroethanol is used, the initial conformation of the peptide is alpha-helical. This then relaxes to an equilibrium state between alpha-helices and beta-strands. The alpha-helix-to beta-strand conversion rate is relatively slow, and this allows the kinetics to be studied by FT-IR spectroscopy. The reverse process is much slower but again can be demonstrated by FT-IR. Thus, it appears that a true equilibrium structure can only be achieved by starting with peptide in the alpha-helical conformation. We believe this result should be of general validity for hydrophobic peptide reconstitution. The implications for conformational changes in membrane proteins are discussed.

Association between the physical stability of flurbiprofen suspension and the interaction of HPMC/SDS

Directory of Open Access Journals (Sweden)

Hongyu Wang

2018-01-01

Full Text Available The anionic surfactant sodium dodecylsulfate (SDS has improved the physical stability of flurbiprofen (FBP suspension, which was suspended by 0.2% (w/v hydroxypropylmethyl cellulose (HPMC, K4M. Therefore, the physical stability of FBP suspensions and the interaction of HPMC/SDS were studied, and a certain association between them was revealed. The anti-solvent precipitation method was used to prepare suspensions. The apparent drug concentration from different sites was evaluated to get the dispersion of drug actually. The process of flocculation and deflocculation with the addition of SDS was caught by analyzing the morphology of the suspended particles. The physical stability of the FBP suspensions was characterized mainly by measuring the re-dispersion time, the zeta potential and particle size. Meanwhile, conductivity measurements were carried out to obtain the characteristic concentrations of SDS in HPMC/SDS system. The viscosities, the abilities for improving the solubility and wettability of FBP in the separate and mixed HPMC/SDS solutions were also contrasted respectively. The suspensions prepared with HPMC/SDS possessed better physical stability. The suspensions were uniform when the concentration of SDS was between the critical adsorption concentration (CAC and the polymer saturation point (PSP. After PSP, the uniformity became worse and worse until the SDS was enough to form a deflocculation state. Besides, the re-dispersion time of FBP suspensions was longest when the concentration of SDS around CAC and shorter by shorter after the critical micelle concentration (CMC. The article provided a new sight on the relation between the interaction of excipient matrix and pharmaceutical preparations.

Boundary Effects and Shear Thickening of Colloidal Suspensions: A study based on measurement of Suspension Microstructure

Science.gov (United States)

Perera, M. Tharanga D.

Microstructure is key to understanding rheological behaviors of flowing particulate suspensions. During the past decade, Stokesian Dynamics simulations have been the dominant method of determining suspension microstructure. Structure results obtained numerically reveal that an anisotropic structure is formed under high Peclet (Pe) number conditions. Researchers have used various experimental techniques such as small angle neutron scattering (SANS) and light scattering methods to validate microstructure. This work outlines an experimental technique based on confocal microscopy to study microstructure of a colloidal suspension in an index-matched fluid flowing in a microchannel. High resolution scans determining individual particle locations in suspensions 30-50 vol % yield quantitative results of the local microstructure in the form of the pair distribution function, g(r). From these experimentally determined g(r), the effect of shear rate, quantified by the Peclet number as a ratio of shear and Brownian stress, on the suspension viscosity and normal stress follow that seen in macroscopic rheological measurements and simulations. It is generally believed that shear thickening behavior of colloidal suspensions is driven by the formation of hydroclusters. From measurements of particle locations, hydroclusters are identified. The number of hydroclusters grows exponentially with increasing Pe, and the onset of shear thickening is driven by the increase in formation of clusters having 5-8 particles. At higher Pe, we notice the emergence of 12 or more particle clusters. The internal structure of these hydroclusters has been investigated, and there is some evidence that particles internal to hydroclusters preferentially align along the 45° and 135° axis. Beyond observations of bulk suspension behavior, the influence of boundaries on suspension microstructure is also investigated. Experiments were performed for suspensions flowing over smooth walls, made of glass

Introducing Dual Suspension System in Road Vehicles

Directory of Open Access Journals (Sweden)

Imtiaz Hussain

2013-04-01

Full Text Available The main objective of suspension system is to reduce the motions of the vehicle body with respect to road disturbances. The conventional suspension systems in road vehicles use passive elements such as springs and dampers to suppress the vibrations induced by the irregularities in the road. But these conventional suspension systems can suppress vibrations to a certain limit. This paper presents a novel idea to improve the ride quality of roads vehicles without compromising vehicle?s stability. The paper proposes the use of primary and secondary suspension to suppress the vibrations more effectively.

NMR spectroscopic studies of a TAT-derived model peptide in imidazolium-based ILs: influence on chemical shifts and the cis/trans equilibrium state.

Science.gov (United States)

Wiedemann, Christoph; Ohlenschläger, Oliver; Mrestani-Klaus, Carmen; Bordusa, Frank

2017-09-13

NMR spectroscopy was used to study systematically the impact of imidazolium-based ionic liquid (IL) solutions on a TAT-derived model peptide containing Xaa-Pro peptide bonds. The selected IL anions cover a wide range of the Hofmeister series of ions. Based on highly resolved one- and two-dimensional NMR spectra individual 1 H and 13 C peptide chemical shift differences were analysed and a classification of IL anions according to the Hofmeister series was derived. The observed chemical shift changes indicate significant interactions between the peptide and the ILs. In addition, we examined the impact of different ILs towards the cis/trans equilibrium state of the Xaa-Pro peptide bonds. In this context, the IL cations appear to be of exceptional importance for inducing an alteration of the native cis/trans equilibrium state of Xaa-Pro bonds in favour of the trans-isomers.

Algorithm For Hypersonic Flow In Chemical Equilibrium

Science.gov (United States)

Palmer, Grant

1989-01-01

Implicit, finite-difference, shock-capturing algorithm calculates inviscid, hypersonic flows in chemical equilibrium. Implicit formulation chosen because overcomes limitation on mathematical stability encountered in explicit formulations. For dynamical portion of problem, Euler equations written in conservation-law form in Cartesian coordinate system for two-dimensional or axisymmetric flow. For chemical portion of problem, equilibrium state of gas at each point in computational grid determined by minimizing local Gibbs free energy, subject to local conservation of molecules, atoms, ions, and total enthalpy. Major advantage: resulting algorithm naturally stable and captures strong shocks without help of artificial-dissipation terms to damp out spurious numerical oscillations.

A new equation of state Based on Nuclear Statistical Equilibrium for Core-Collapse Simulations

Science.gov (United States)

Furusawa, Shun; Yamada, Shoichi; Sumiyoshi, Kohsuke; Suzuki, Hideyuki

2012-09-01

We calculate a new equation of state for baryons at sub-nuclear densities for the use in core-collapse simulations of massive stars. The formulation is the nuclear statistical equilibrium description and the liquid drop approximation of nuclei. The model free energy to minimize is calculated by relativistic mean field theory for nucleons and the mass formula for nuclei with atomic number up to ~ 1000. We have also taken into account the pasta phase. We find that the free energy and other thermodynamical quantities are not very different from those given in the standard EOSs that adopt the single nucleus approximation. On the other hand, the average mass is systematically different, which may have an important effect on the rates of electron captures and coherent neutrino scatterings on nuclei in supernova cores.

Universality in equilibrium and away from it: A personal perspective

International Nuclear Information System (INIS)

Munoz, Miguel A.

2011-01-01

In this talk/paper I discuss the concept of universality in phase transitions and the question of whether universality classes are more robust in equilibrium than away from it. In both of these situations, the main ingredients determining universality are symmetries, conservation laws, the dimension of the space and of the order-parameter and the presence of long-range interactions or quenched disorder. The existence of detailed-balance and fluctuation-dissipation theorems imposes severe constraints on equilibrium systems, allowing to define universality classes in a very robust way; instead, non-equilibrium allows for more variability. Still, quite robust non-equilibrium universality classes have been identified in the last decades. Here, I discuss some examples in which (i) non-equilibrium phase transitions are simply controlled by equilibrium critical points, i.e. non-equilibrium ingredients turn out to be irrelevant in the renormalization group sense and (ii) non-equilibrium situations in which equilibrium seems to come out of the blue, generating an adequate effective description of intrinsically non-equilibrium problems. Afterwards, I shall describe different genuinely non-equilibrium phase transitions in which introducing small, apparently innocuous changes (namely: presence or absence of an underlying lattice, parity conservation in the overall number of particles, existence of an un-accessible vacuum state, deterministic versus stochastic microscopic rules, presence or absence of a Fermionic constraint), the critical behavior is altered, making the case for lack of robustness. However, it will be argued that in all these examples, there is an underlying good reason (in terms of general principles) for universality to be altered. The final conclusions are that: (i) robust universality classes exist both in equilibrium and non-equilibrium; (ii) symmetry and conservation principles are crucial in both, (iii) non-equilibrium allows for more variability (i

Noise-Induced Modulation of the Relaxation Kinetics around a Non-Equilibrium Steady State of Non-Linear Chemical Reaction Networks

OpenAIRE

Ramaswamy, Rajesh; Sbalzarini, Ivo F; González-Segredo, Nélido

2011-01-01

Stochastic effects from correlated noise non-trivially modulate the kinetics of non-linear chemical reaction networks. This is especially important in systems where reactions are confined to small volumes and reactants are delivered in bursts. We characterise how the two noise sources confinement and burst modulate the relaxation kinetics of a non-linear reaction network around a non-equilibrium steady state. We find that the lifetimes of species change with burst input and confinement. Confi...

Electrostratic stabilization of suspensions in non-aqueous media

NARCIS (Netherlands)

Hoeven, van der P.C.

1991-01-01

Concentrated suspensions of detergent powder solids in a liquid nonionic surfactant are considered for practical application as liquid detergent products. If no precautions are taken, upon storage the viscosity of such suspensions increases and the pourability drops because the suspensions are

Isospin equilibrium and non-equilibrium in heavy-ion collisions at intermediate energies

International Nuclear Information System (INIS)

Chen Liewen; Ge Lingxiao; Zhang Xiaodong; Zhang Fengshou

1997-01-01

The equilibrium and non-equilibrium of the isospin degree of freedom are studied in terms of an isospin-dependent QMD model, which includes isospin-dependent symmetry energy, Coulomb energy, N-N cross sections and Pauli blocking. It is shown that there exists a transition from the isospin equilibrium to non-equilibrium as the incident energy from below to above a threshold energy in central, asymmetric heavy-ion collisions. Meanwhile, it is found that the phenomenon results from the co-existence and competition of different reaction mechanisms, namely, the isospin degree of freedom reaches an equilibrium if the incomplete fusion (ICF) component is dominant and does not reach equilibrium if the fragmentation component is dominant. Moreover, it is also found that the isospin-dependent N-N cross sections and symmetry energy are crucial for the equilibrium of the isospin degree of freedom in heavy-ion collisions around the Fermi energy. (author)

Adaptive suspension strategy for a double wishbone suspension through camber and toe optimization

Directory of Open Access Journals (Sweden)

C. Kavitha

2018-02-01

Full Text Available A suspension system is responsible for the safety of vehicle during its manoeuvre. It serves the dual purpose of providing stability to the vehicle while providing a comfortable ride quality to the occupants. Recent trends in suspension system have focused on improving comfort and handling of vehicles while keeping the cost, space and feasibility of manufacturing in the constraint. This paper proposes a method for improving handling characteristics of a vehicle by controlling camber and toe angle using variable length arms in an adaptive manner. In order to study the effect of dynamic characteristics of the suspension system, a simulation study has been done in this work. A quarter car physical model with double wishbone suspension geometry is modelled in SolidWorks. It is then imported and simulated using SimMechanics platform in MATLAB. The output characteristics of the passive system (without variable length arms were validated on MSC ADAMS software. The adaptive system intends to improve vehicle handling characteristics by controlling the camber and toe angles. This is accomplished by two telescopic arms with an actuator which changes the camber and toe angle of the wheel dynamically to deliver best possible traction and manoeuvrability. Two PID controllers are employed to trigger the actuators based on the camber and toe angle from the sensors for reducing the error existing between the actual and desired value. The arms are driven by actuators in a closed loop feedback manner with help of a separate control system. Comparison between active and passive systems is carried out by analysing graphs of various parameters obtained from MATLAB simulation. From the results, it is observed that there is a reduction of 58% in the camber and 96% in toe gain. Hence, the system provides the scope of considerable adaptive strategy in controlling dynamic characteristics of the suspension system.

14 CFR 399.41 - Zones of limited suspension for international cargo rates.

Science.gov (United States)

2010-01-01

... TRANSPORTATION (AVIATION PROCEEDINGS) POLICY STATEMENTS STATEMENTS OF GENERAL POLICY Policies Relating to Rates and Tariffs § 399.41 Zones of limited suspension for international cargo rates. (a) Applicability. This section states the Board's policy for suspending rate changes for the transportation of property...

Adaptive Equilibrium Regulation: A Balancing Act in Two Timescales

Science.gov (United States)

Boker, Steven M.

2015-01-01

An equilibrium involves a balancing of forces. Just as one maintains upright posture in standing or walking, many self-regulatory and interpersonal behaviors can be framed as a balancing act between an ever changing environment and within-person processes. The emerging balance between person and environment, the equilibria, are dynamic and adaptive in response to development and learning. A distinction is made between equilibrium achieved solely due to a short timescale balancing of forces and a longer timescale preferred equilibrium which we define as a state towards which the system slowly adapts. Together, these are developed into a framework that this article calls Adaptive Equilibrium Regulation (ÆR), which separates a regulatory process into two timescales: a faster regulation that automatically balances forces and a slower timescale adaptation process that reconfigures the fast regulation so as to move the system towards its preferred equilibrium when an environmental force persists over the longer timescale. This way of thinking leads to novel models for the interplay between multiple timescales of behavior, learning, and development. PMID:27066197

Imploding to equilibrium of helically symmetric theta pinches

International Nuclear Information System (INIS)

Sharky, N.N.

1978-01-01

The time-dependent, single-fluid, dissipative magnetohydrodynamic equations are solved in helical coordinates (r,phi), where phi = THETA-kz, k = 2π/L and L is the periodicity length in the z-direction. The two-dimensional numerical calculations simulate theta pinches which have an l = 1 helical field added to them. Given the applied magnetic fields and the initial state of the plasma, we study the time evolution of the system. The plasma is found to experience two kinds of oscillations, occurring on different time scales. These are the radial compression oscillations, and the slower helical oscillations of the plasma column. The plasma motion is followed until these oscillations disappear and an equilibrium is nearly reached. Hence given the amplitude and the rise time of the applied magnetic fields, the calculations allow one to relate the initial state of a cold, homogeneous plasma to its final equilibrium state where it is heated and compressed

System and technique for ultrasonic characterization of settling suspensions

Energy Technology Data Exchange (ETDEWEB)

Greenwood, Margaret S [Richland, WA; Panetta, Paul D [Richland, WA; Bamberger, Judith A [Richland, WA; Pappas, Richard A [Richland, WA

2006-11-28

A system for determining properties of settling suspensions includes a settling container, a mixer, and devices for ultrasonic interrogation transverse to the settling direction. A computer system controls operation of the mixer and the interrogation devices and records the response to the interrogating as a function of settling time, which is then used to determine suspension properties. Attenuation versus settling time for dilute suspensions, such as dilute wood pulp suspension, exhibits a peak at different settling times for suspensions having different properties, and the location of this peak is used as one mechanism for characterizing suspensions. Alternatively or in addition, a plurality of ultrasound receivers are arranged at different angles to a common transmitter to receive scattering responses at a variety of angles during particle settling. Angular differences in scattering as a function of settling time are also used to characterize the suspension.

Coherent application of a contact structure to formulate Classical Non-Equilibrium Thermodynamics

NARCIS (Netherlands)

Knobbe, E; Roekaerts, D.J.E.M.

2017-01-01

This contribution presents an outline of a new mathematical formulation for
Classical Non-Equilibrium Thermodynamics (CNET) based on a contact
structure in differential geometry. First a non-equilibrium state space is introduced as the third key element besides the first and second law of

Hybrid superconducting magnetic suspensions

International Nuclear Information System (INIS)

Tixador, P.; Hiebel, P.; Brunet, Y.; Chaud, X.; Gautier-Picard, P.

1996-01-01

Superconductors, especially high T c ones, are the most attractive materials to design stable and fully passive magnetic suspensions which have to control five degrees of freedom. The hybrid superconducting magnetic suspensions present high performances and a simple cooling mode. They consist of a permanent magnet bearing, stabilized by a suitable magnet-superconductor structure. Several designs are given and compared in terms of forces and stiffnesses. The design of the magnet bearing plays an important part. The superconducting magnetic bearing participates less in levitation but must provide a high stabilizing stiffness. This is achieved by the magnet configuration, a good material in term of critical current density and field cooling. A hybrid superconducting suspension for a flywheel is presented. This system consists of a magnet thrust bearing stabilized by superconductors interacting with an alternating polarity magnet structure. First tests and results are reported. Superconducting materials are magnetically melt-textured YBaCuO

Statistical approach to partial equilibrium analysis

Science.gov (United States)

Wang, Yougui; Stanley, H. E.

2009-04-01

A statistical approach to market equilibrium and efficiency analysis is proposed in this paper. One factor that governs the exchange decisions of traders in a market, named willingness price, is highlighted and constitutes the whole theory. The supply and demand functions are formulated as the distributions of corresponding willing exchange over the willingness price. The laws of supply and demand can be derived directly from these distributions. The characteristics of excess demand function are analyzed and the necessary conditions for the existence and uniqueness of equilibrium point of the market are specified. The rationing rates of buyers and sellers are introduced to describe the ratio of realized exchange to willing exchange, and their dependence on the market price is studied in the cases of shortage and surplus. The realized market surplus, which is the criterion of market efficiency, can be written as a function of the distributions of willing exchange and the rationing rates. With this approach we can strictly prove that a market is efficient in the state of equilibrium.

Stability and spring constant investigation for micromachined inductive suspensions: theoretical analysis vs. experimental results

International Nuclear Information System (INIS)

Poletkin, K; Lu, Z; Wallrabe, U; Badilita, V; Den Hartogh, B

2014-01-01

We present a linear analytical model coupled with experimental analysis to discuss stability of a levitated proof mass (PM) in a micromachined inductive suspension (MIS), which has been previously introduced and characterized. The model is a function of the MIS geometry, describes the dynamics of a levitated disk-shaped PM near the equilibrium point, and predicts conditions for stable levitation. The experimental setup directly measures the lateral component of the Lorentz force, which has a stabilization role in the MIS structure, as well as the vertical levitation force. The experimental setup is further used to derive mechanical parameters such as stiffness values relative to lateral, vertical and angular displacements, proven to be in excellent agreement with the values predicted by the analytical model

Speeding up compositional reservoir simulation through an efficient implementation of phase equilibrium calculation

DEFF Research Database (Denmark)

Belkadi, Abdelkrim; Yan, Wei; Moggia, Elsa

2013-01-01

Compositional reservoir simulations are widely used to simulate reservoir processes with strong compositional effects, such as gas injection. The equations of state (EoS) based phase equilibrium calculation is a time consuming part in this type of simulations. The phase equilibrium problem can....... Application of the shadow region method to skip stability analysis can further cut the phase equilibrium calculation time. Copyright 2013, Society of Petroleum Engineers....

Attractive and repulsive magnetic suspension systems overview

Science.gov (United States)

Cope, David B.; Fontana, Richard R.

1992-01-01

Magnetic suspension systems can be used in a wide variety of applications. The decision of whether to use an attractive or repulsive suspension system for a particular application is a fundamental one which must be made during the design process. As an aid to the designer, we compare and contrast attractive and repulsive magnetic suspension systems and indicate whether and under what conditions one or the other system is preferred.

Ensemble-average versus suspension-scale Cauchy continuum-mechanical definitions of stress in polarized suspensions: Global homogenization of a dilute suspension of dipolar spherical particles

International Nuclear Information System (INIS)

Almog, Y.; Brenner, H.

1999-01-01

The macroscale rheological properties of a dilute suspension exposed to a uniform external field and composed of identical, rigid, inhomogeneous, dipolar, spherical particles dispersed in an incompressible Newtonian fluid and possessing the same mean density as the latter fluid are derived from knowledge of its microscale properties by applying a global ensemble-averaging technique. Each dipole, which is permanently embedded in the particle, is assumed to be generated by the presence of an inhomogeneous external body-force field in the particle interior resulting from the action of the uniform external field on an inhomogeneous distribution of interior matter. It is shown that although the ensemble-average stress tensor is symmetric, the suspension nevertheless behaves macroscopically as if it possessed an asymmetric stress tensor. This seeming contradiction can be traced to the fact that the average body force acting on the contents of any arbitrarily drawn volume lying in the interior of the suspension does not vanish despite the fact that each particle is 'neutrally buoyant'. That this force is not zero stems from the fact that some particles necessarily straddle the closed surface bounding that volume, and that the distribution of external body forces over the interiors of these particles is nonuniform. As such, that portion of the spherical particle lying outside of the surface enclosing the domain exerts a force on the remaining portion of the sphere lying within that domain. We then demonstrate that the natural macroscopic model, which is derived by equating the divergence of the suspension-scale stress appearing in that model to the ensemble-average external body-force field, and which predicts a symmetric stress tensor, is macroscopically deficient with respect to the more intuitive asymmetric stress model usually proposed by continuum mechanicians for such a suspension. It is shown that the latter, continuum-mechanical model recovers all the physically

Steady-State Electrodiffusion from the Nernst-Planck Equation Coupled to Local Equilibrium Monte Carlo Simulations.

Science.gov (United States)

Boda, Dezső; Gillespie, Dirk

2012-03-13

We propose a procedure to compute the steady-state transport of charged particles based on the Nernst-Planck (NP) equation of electrodiffusion. To close the NP equation and to establish a relation between the concentration and electrochemical potential profiles, we introduce the Local Equilibrium Monte Carlo (LEMC) method. In this method, Grand Canonical Monte Carlo simulations are performed using the electrochemical potential specified for the distinct volume elements. An iteration procedure that self-consistently solves the NP and flux continuity equations with LEMC is shown to converge quickly. This NP+LEMC technique can be used in systems with diffusion of charged or uncharged particles in complex three-dimensional geometries, including systems with low concentrations and small applied voltages that are difficult for other particle simulation techniques.

Ventilation rate in equilibrium factor measurements with solid state nuclear track detectors (SSNTD)

International Nuclear Information System (INIS)

Gil, L.R.; Leitao, R.M.S.; Marques, A.; Rivera, A.

1994-08-01

Ventilation rate values are calculated from track density measurements in solid state nuclear track detectors (SSNTD), both when ventilation is the main cause of radioactive disequilibrium in radon progeny and when it shares importance with other agents. The method consists in exposing a SSNTD of high intrinsic efficiency (CR-39) in filtered and unfiltered conditions and, in addition, covered with a thin Aluminium foil, to stop alpha particles from 218 Po and 222 Rn. No calibrations are required but, when necessary, independent measurements of the loss rates of radioactivity to aerosol and to walls have to perform. Ventilation rates depend upon geometry detection efficiencies for alpha particles, here obtained by Monte Carlo simulation, taking into account the space distribution of emission positions. This may lead to sizeable corrections in ventilation and equilibrium factor values. Since geometric detection efficiencies depend upon alpha-particle ranges in air, the influences of barometric variables are also discussed. (author). 7 refs

Continuum model of non-equilibrium solvation and solvent effect on ultra-fast processes

International Nuclear Information System (INIS)

Li Xiangyuan; Fu Kexiang; Zhu Quan

2006-01-01

In the past 50 years, non-equilibrium solvation theory for ultra-fast processes such as electron transfer and light absorption/emission has attracted particular interest. A great deal of research efforts was made in this area and various models which give reasonable qualitative descriptions for such as solvent reorganization energy in electron transfer and spectral shift in solution, were developed within the framework of continuous medium theory. In a series of publications by the authors, we clarified that the expression of the non-equilibrium electrostatic free energy that is at the dominant position of non-equilibrium solvation and serves as the basis of various models, however, was incorrectly formulated. In this work, the authors argue that reversible charging work integration was inappropriately applied in the past to an irreversible path linking the equilibrium or the non-equilibrium state. Because the step from the equilibrium state to the nonequilibrium state is factually thermodynamically irreversible, the conventional expression for non-equilibrium free energy that was deduced in different ways is unreasonable. Here the authors derive the non-equilibrium free energy to a quite different form according to Jackson integral formula. Such a difference throws doubts to the models including the famous Marcus two-sphere model for solvent reorganization energy of electron transfer and the Lippert-Mataga equation for spectral shift. By introducing the concept of 'spring energy' arising from medium polarizations, the energy constitution of the non-equilibrium state is highlighted. For a solute-solvent system, the authors separate the total electrostatic energy into different components: the self-energies of solute charge and polarized charge, the interaction energy between them and the 'spring energy' of the solvent polarization. With detailed reasoning and derivation, our formula for non-equilibrium free energy can be reached through different ways. Based on the

Equilibrium Structure of Manganese Trifluoride (MnF3) Molecule

International Nuclear Information System (INIS)

Caliskan, M.

2004-01-01

The symmetry lowering in manganese trifluoride molecule due to Jahn-Teller distortion was demonstrated in both the experimental and computational results. The molecule does not have D 3 h (or C 3 v) symmetry, rather it has C 2 v symmetry it has been shown from electron-diffraction measurements, that even a molecule of D 3 h symmetry in its equilibrium geometry would appear as having C 3 v symmetry. The manganese trifluoride molecular structures is an example of concerted applications of electron diffraction experiment and computation. It was found two lower energy structures with C 2 v symmetry, one corresponding to the ground state and another corresponding to the transition state. In this work we have calculate the equilibrium structure of the MnF 3 in the C 2 v configuration using the Interionic Force Model. We have compared our results for equilibrium bond lengths and bond angles with measured values from electron diffraction and with the results of quantum chemical calculations. The agreement can be considered as very reasonable

Controlling competing electronic orders via non-equilibrium acoustic phonons

Science.gov (United States)

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.

Fracture in Kaolinite clay suspensions

Science.gov (United States)

Kosgodagan Acharige, Sebastien; Jerolmack, Douglas J.; Arratia, Paulo E.

2017-11-01

Clay minerals are involved in many natural (landslides, river channels) and industrial processes (ceramics, cosmetics, oil recovery). They are plate shaped charged colloids and exhibit different flow properties than simpler colloids when suspended in a liquid such as thixotropy and shear-banding. kaolinite platelets are non-swelling, meaning that the stacks formed by the platelets do not have water layers, and thus the suspension does not have a sol-gel transition. However, it has been shown that kaolinite suspensions possesses a non-zero yield stress even at low concentrations, indicating that the particles arrange themselves in a structure through attractive interactions. Here, we experimentally investigate the sedimentation of kaolinite suspensions in a Hele-Shaw cell. The sedimentation of these dilute suspensions can display solid behavior like fracture, revealed in cross-polarized light, which is linked to the failure of the weakly-bonded structure (typical yield stress 10-2 Pa). By changing the interaction potential of the particles (by sonication or introducing salts), we show through these sedimentation experiments, how the fracture pattern can be avoided. Research was sponsored by the Army Research Laboratory and was accomplished under Grant Number 569074.

Quantum Cournot equilibrium for the Hotelling–Smithies model of product choice

International Nuclear Information System (INIS)

Rahaman, Ramij; Majumdar, Priyadarshi; Basu, B

2012-01-01

This paper demonstrates the quantization of a spatial Cournot duopoly model with product choice, a two stage game focusing on non-cooperation in locations and quantities. With quantization, the players can access a continuous set of strategies, using a continuous variable quantum mechanical approach. The presence of quantum entanglement in the initial state identifies a quantity equilibrium for each location pair choice with any transport cost. Also higher profit is obtained by the firms at Nash equilibrium. Adoption of quantum strategies rewards us by the existence of a larger quantum strategic space at equilibrium. (paper)

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

26 CFR 301.6503(c)-1 - Suspension of running of period of limitation; location of property outside the United States or...

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Suspension of running of period of limitation... Limitations on Assessment and Collection § 301.6503(c)-1 Suspension of running of period of limitation... November 3, 1966. The running of the period of limitations on collection after assessment prescribed in...

A Novel Derivation of the Time Evolution of the Entropy for Macroscopic Systems in Thermal Non-Equilibrium

Directory of Open Access Journals (Sweden)

Enrico Sciubba

2017-11-01

Full Text Available The paper discusses how the two thermodynamic properties, energy (U and exergy (E, can be used to solve the problem of quantifying the entropy of non-equilibrium systems. Both energy and exergy are a priori concepts, and their formal dependence on thermodynamic state variables at equilibrium is known. Exploiting the results of a previous study, we first calculate the non-equilibrium exergy En-eq can be calculated for an arbitrary temperature distributions across a macroscopic body with an accuracy that depends only on the available information about the initial distribution: the analytical results confirm that En-eq exponentially relaxes to its equilibrium value. Using the Gyftopoulos-Beretta formalism, a non-equilibrium entropy Sn-eq(x,t is then derived from En-eq(x,t and U(x,t. It is finally shown that the non-equilibrium entropy generation between two states is always larger than its equilibrium (herein referred to as “classical” counterpart. We conclude that every iso-energetic non-equilibrium state corresponds to an infinite set of non-equivalent states that can be ranked in terms of increasing entropy. Therefore, each point of the Gibbs plane corresponds therefore to a set of possible initial distributions: the non-equilibrium entropy is a multi-valued function that depends on the initial mass and energy distribution within the body. Though the concept cannot be directly extended to microscopic systems, it is argued that the present formulation is compatible with a possible reinterpretation of the existing non-equilibrium formulations, namely those of Tsallis and Grmela, and answers at least in part one of the objections set forth by Lieb and Yngvason. A systematic application of this paradigm is very convenient from a theoretical point of view and may be beneficial for meaningful future applications in the fields of nano-engineering and biological sciences.

36 CFR 296.10 - Suspension and revocation of permits.

Science.gov (United States)

2010-07-01

... AGRICULTURE PROTECTION OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 296.10 Suspension and revocation of... correct the situation which led to suspension of the permit. (b) Suspension or revocation for management...

Linear viscoelastic properties of aging suspensions

NARCIS (Netherlands)

Purnomo, E.H.; Purnomo, E.H; van den Ende, Henricus T.M.; Mellema, J.; Mugele, Friedrich Gunther

2006-01-01

We have examined the linear viscoelastic behavior of poly-N-isopropylacrylamide (PNIPAM) microgel suspensions in order to obtain insight in the aging processes in these densely packed suspensions at various temperatures below the volume transition temperature. The system is found to display a strong

Multiscale measures of equilibrium on finite dynamic systems

International Nuclear Information System (INIS)

Bigerelle, M.; Iost, A.

2004-01-01

This article presents a new method for the study of the evolution of dynamic systems based on the notion of quantity of information. The system is divided into elementary cells and the quantity of information is studied with respect to the cell size. We have introduced an analogy between quantity of information and entropy, and defined the intrinsic entropy as the entropy of the whole system independent of the size of the cells. It is shown that the intrinsic entropy follows a Gaussian probability density function (PDF) and thereafter, the time needed by the system to reach equilibrium is a random variable. For a finite system, statistical analyses show that this entropy converges to a state of equilibrium and an algorithmic method is proposed to quantify the time needed to reach equilibrium for a given confidence interval level. A Monte-Carlo simulation of diffusion of A* atoms in A is then provided to illustrate the proposed simulation. It follows that the time to reach equilibrium for a constant error probability, t e , depends on the number, n, of elementary cells as: t e ∝n 2.22 ±0.06 . For an infinite system size (n infinite), the intrinsic entropy obtained by statistical modelling is a pertinent characteristic number of the system at the equilibrium

Equilibrium fluctuation relations for voltage coupling in membrane proteins.

Science.gov (United States)

Kim, Ilsoo; Warshel, Arieh

2015-11-01

A general theoretical framework is developed to account for the effects of an external potential on the energetics of membrane proteins. The framework is based on the free energy relation between two (forward/backward) probability densities, which was recently generalized to non-equilibrium processes, culminating in the work-fluctuation theorem. Starting from the probability densities of the conformational states along the "voltage coupling" reaction coordinate, we investigate several interconnected free energy relations between these two conformational states, considering voltage activation of ion channels. The free energy difference between the two conformational states at zero (depolarization) membrane potential (i.e., known as the chemical component of free energy change in ion channels) is shown to be equivalent to the free energy difference between the two "equilibrium" (resting and activated) conformational states along the one-dimensional voltage couplin reaction coordinate. Furthermore, the requirement that the application of linear response approximation to the free energy functionals of voltage coupling should satisfy the general free energy relations, yields a novel closed-form expression for the gating charge in terms of other basic properties of ion channels. This connection is familiar in statistical mechanics, known as the equilibrium fluctuation-response relation. The theory is illustrated by considering the coupling of a unit charge to the external voltage in the two sites near the surface of membrane, representing the activated and resting states. This is done using a coarse-graining (CG) model of membrane proteins, which includes the membrane, the electrolytes and the electrodes. The CG model yields Marcus-type voltage dependent free energy parabolas for the response of the electrostatic environment (electrolytes etc.) to the transition from the initial to the final configuratinal states, leading to equilibrium free energy difference and free

39 CFR 320.9 - Revocation or amendment of suspensions.

Science.gov (United States)

2010-07-01

... SUSPENSION OF THE PRIVATE EXPRESS STATUTES § 320.9 Revocation or amendment of suspensions. These suspensions... of operations (in dollar or volume terms, whichever is larger) lower than that antedating the...

Scaling studies of spheromak formation and equilibrium

International Nuclear Information System (INIS)

Geddes, C.G.; Kornack, T.W.; Brown, M.R.

1998-01-01

Formation and equilibrium studies have been performed on the Swarthmore Spheromak Experiment (SSX). Spheromaks are formed with a magnetized coaxial plasma gun and equilibrium is established in both small (d small =0.16 m) and large (d large =3d small =0.50 m) copper flux conservers. Using magnetic probe arrays it has been verified that spheromak formation is governed solely by gun physics (in particular the ratio of gun current to flux, μ 0 I gun /Φ gun ) and is independent of the flux conserver dimensions. It has also been verified that equilibrium is well described by the force free condition ∇xB=λB (λ=constant), particularly early in decay. Departures from the force-free state are due to current profile effects described by a quadratic function λ=λ(ψ). Force-free SSX spheromaks will be merged to study magnetic reconnection in simple magnetofluid structures. copyright 1998 American Institute of Physics

Spectral Quasi-Equilibrium Manifold for Chemical Kinetics.

Science.gov (United States)

Kooshkbaghi, Mahdi; Frouzakis, Christos E; Boulouchos, Konstantinos; Karlin, Iliya V

2016-05-26

The Spectral Quasi-Equilibrium Manifold (SQEM) method is a model reduction technique for chemical kinetics based on entropy maximization under constraints built by the slowest eigenvectors at equilibrium. The method is revisited here and discussed and validated through the Michaelis-Menten kinetic scheme, and the quality of the reduction is related to the temporal evolution and the gap between eigenvalues. SQEM is then applied to detailed reaction mechanisms for the homogeneous combustion of hydrogen, syngas, and methane mixtures with air in adiabatic constant pressure reactors. The system states computed using SQEM are compared with those obtained by direct integration of the detailed mechanism, and good agreement between the reduced and the detailed descriptions is demonstrated. The SQEM reduced model of hydrogen/air combustion is also compared with another similar technique, the Rate-Controlled Constrained-Equilibrium (RCCE). For the same number of representative variables, SQEM is found to provide a more accurate description.

Nonlinear Predictive Sliding Mode Control for Active Suspension System

Directory of Open Access Journals (Sweden)

Dazhuang Wang

2018-01-01

Full Text Available An active suspension system is important in meeting the requirements of the ride comfort and handling stability for vehicles. In this work, a nonlinear model of active suspension system and a corresponding nonlinear robust predictive sliding mode control are established for the control problem of active suspension. Firstly, a seven-degree-of-freedom active suspension model is established considering the nonlinear effects of springs and dampers; and secondly, the dynamic model is expanded in the time domain, and the corresponding predictive sliding mode control is established. The uncertainties in the controller are approximated by the fuzzy logic system, and the adaptive controller reduces the approximation error to increase the robustness of the control system. Finally, the simulation results show that the ride comfort and handling stability performance of the active suspension system is better than that of the passive suspension system and the Skyhook active suspension. Thus, the system can obviously improve the shock absorption performance of vehicles.

Cements and concentrated model suspensions. Flow, jamming and flocculation; Ciments et suspensions concentrees modeles. Ecoulement, encombrement et floculation

Energy Technology Data Exchange (ETDEWEB)

Lootens, D

2004-10-15

Here we report about the rheological behavior of very concentrated dispersions -or pastes- of granular or colloidal particles of cement or of monodisperse spherical silica particles. The model system of silica particles is used in order to control the physical chemistry properties of the suspension. Our research project is centered on two points which are focusing on the slurries properties: (i) the first one is the study of the structuring process by the coagulation at rest and its relation with setting. We use special tools (ultrasonic, confocal) to follow and understand the evolution from coagulation to the setting of cement (ii) the second is the study of the dynamic structuring phenomena, under shear, typical of the concentrated suspensions and named jamming. The flow can enter into a shear-thickening and, possibly jamming regime. The onset of this regime is shown to involve giant fluctuations of stress, assigned to the formation and breakup of direct frictional contact chains. The surface state of the particles is a determining factor in this transition. The studies of the normal stress and microscopic observation give good reasons to believe that solid friction is involved in the jamming transition. (author)

41 CFR 105-74.670 - Suspension.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Suspension. 105-74.670 Section 105-74.670 Public Contracts and Property Management Federal Property Management Regulations System...-GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Definitions § 105-74.670 Suspension...

Behaviour of humic-bentonite aggregates in diluted suspensions ...

African Journals Online (AJOL)

Formation and disaggregation of micron-size aggregates in a diluted suspension made up of HSs and bentonite (B) were studied by tracing distribution of aggregate sizes and their counts in freshly prepared and aged suspensions, and at high (10 000) and low (1.0) [HS]/[B] ratios. Diluted HSB suspensions are unstable ...

Yield stress of alumina-zirconia suspensions

International Nuclear Information System (INIS)

Ramakrishnan, V.; Pradip; Malghan, S.G.

1996-01-01

The yield stress of concentrated suspensions of alumina, zirconia, and mixed alumina-zirconia powders was measured by the vane technique as a function of solids loading, relative amounts of alumina and zirconia, and pH. At the isoelectric point (IEP), the yield stress varied as the fourth power of the solids loading. The relative ratio of alumina and zirconia particles was important in determining the yield stress of the suspension at the IEP. The yield stress of single and mixed suspensions showed a marked variation with pH. The maximum value occurred at or near the IEP of the suspension. The effect of electrical double-layer forces on the yield stress can be described on the basis of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. A normalized yield stress--that is, the ratio of the yield stress at a given pH to the yield stress at the IEP predicted by this model--showed good correlation with experimental data

Vaginal vault suspension during hysterectomy for benign indications

DEFF Research Database (Denmark)

Bonde, Lisbeth; Noer, Mette Calundann; Møller, Lars Alling

2017-01-01

Introduction and hypothesis: Several suspension methods are used to try to prevent pelvic organ prolapse (POP) after hysterectomy. We aimed to evaluate agreement on terminology and surgical procedure of these methods. Methods: We randomly chose 532 medical records of women with a history......: Regarding medical records, agreement on terminology was good among patients undergoing pooled suspension in cases of hysterectomy via the abdominal and vaginal route (agreement 78.7, 92.3%). Regarding videos, agreement on surgical procedure was good among pooled suspension patients in cases of hysterectomy...... via the abdominal, laparoscopic, and vaginal routes (agreement 88.9, 97.8, 100%). Agreement on individual suspension methods differed regarding both medical records (agreement 0–90.1%) and videos (agreement 0–100%). Conclusions: Agreement on terminology and surgical procedure regarding suspension...

Microstructural Dynamics and Rheology of Suspensions of Rigid Fibers

Science.gov (United States)

Butler, Jason E.; Snook, Braden

2018-01-01

The dynamics and rheology of suspensions of rigid, non-Brownian fibers in Newtonian fluids are reviewed. Experiments, theories, and computer simulations are considered, with an emphasis on suspensions at semidilute and concentrated conditions. In these suspensions, interactions between the particles strongly influence the microstructure and rheological properties of the suspension. The interactions can arise from hydrodynamic disturbances, giving multibody interactions at long ranges and pairwise lubrication forces over short distances. For concentrated suspensions, additional interactions due to excluded volume (contacts) and adhesive forces are addressed. The relative importance of the various interactions as a function of fiber concentration is assessed.

Pre-equilibrium assumptions and statistical model parameters effects on reaction cross-section calculations

International Nuclear Information System (INIS)

Avrigeanu, M.; Avrigeanu, V.

1992-02-01

A systematic study on effects of statistical model parameters and semi-classical pre-equilibrium emission models has been carried out for the (n,p) reactions on the 56 Fe and 60 Co target nuclei. The results obtained by using various assumptions within a given pre-equilibrium emission model differ among them more than the ones of different models used under similar conditions. The necessity of using realistic level density formulas is emphasized especially in connection with pre-equilibrium emission models (i.e. with the exciton state density expression), while a basic support could be found only by replacement of the Williams exciton state density formula with a realistic one. (author). 46 refs, 12 figs, 3 tabs

Introducing Dual Suspension System in Road Vehicles

OpenAIRE

Imtiaz Hussain; Jawaid Daudpoto; Ali Asghar Memon

2013-01-01

The main objective of suspension system is to reduce the motions of the vehicle body with respect to road disturbances. The conventional suspension systems in road vehicles use passive elements such as springs and dampers to suppress the vibrations induced by the irregularities in the road. But these conventional suspension systems can suppress vibrations to a certain limit. This paper presents a novel idea to improve the ride quality of roads vehicles without compromising vehicle?s stability...

Non-equilibrium coherence dynamics in one-dimensional Bose gases

DEFF Research Database (Denmark)

Hofferberth, S.; Lesanovsky, Igor; Fischer, B.

2007-01-01

Low-dimensional systems provide beautiful examples of many-body quantum physics. For one-dimensional (1D) systems, the Luttinger liquid approach provides insight into universal properties. Much is known of the equilibrium state, both in the weakly and strongly interacting regimes. However......, the coherence factor is observed to approach a non-zero equilibrium value, as predicted by a Bogoliubov approach. This coupled-system decay to finite coherence is the matter wave equivalent of phase-locking two lasers by injection. The non-equilibrium dynamics of superfluids has an important role in a wide...... range of physical systems, such as superconductors, quantum Hall systems, superfluid helium and spin systems. Our experiments studying coherence dynamics show that 1D Bose gases are ideally suited for investigating this class of phenomena....

Rheology of dense suspensions of non colloidal particles

Science.gov (United States)

Guazzelli, Élisabeth

2017-06-01

Dense suspensions are materials with broad applications both in industrial processes (e.g. waste disposal, concrete, drilling muds, metalworking chip transport, and food processing) and in natural phenomena (e.g. flows of slurries, debris, and lava). Despite its long research history and its practical relevance, the mechanics of dense suspensions remain poorly understood. The major difficulty is that the grains interact both by hydrodynamic interactions through the liquid and by mechanical contact. These systems thus belong to an intermediate regime between pure suspensions and granular flows. We show that we can unify suspension and granular rheology under a common framework by transferring the frictional approach of dry granular media to wet suspensions of spherical particles. We also discuss non-Newtonian behavior such as normal-stress differences and shear-induced migration. Beyond the classical problem of dense suspension of hard spheres which is far from being completely resolved, there are also entirely novel avenues of study concerning more complex mixtures of particles and fluids such as those involving other types of particles (e.g. fibers) or non-Newtonian fluids that we will also address.

Development of A New Automotive Active Suspension System

Science.gov (United States)

Yousef Abdulhammed, Eng.; Eng. Hisham Elsherif, Dr, Prof.

2017-12-01

The main objective was to develop a smart new vehicle suspension system that minimizes the road irregularities impact on the driver, also to increase performance and stability of the vehicle at high speeds. The central idea is based on modifying the normal passive suspension system into a computer controller hydraulic actuated active suspension system simply by adding a new component such as a hydraulic cylinder on a normal passive system. The new suspension system is economical to be wildly used in consumer’s cars with low prices. The new added components was analytically tested and modeled according to different parameters. A new test rig was implemented to simulate a real quarter suspension system. The new suspension model was controlled by feedback controller according to the road conditions; the controller output controls the cylinder actuator to compensate the road oscillations and increases the vehicle stability for the passenger. Finally, to maximize the aerodynamics coefficients of the vehicle during high speeds by controlling the vehicle clearance level from the ground to achieve full stability, steering and fuel economy.

Analysis of Train Suspension System Using MR dampers

Science.gov (United States)

RamaSastry, DVA; Ramana, K. V.; Mohan Rao, N.; Siva Kumar, SVR; Priyanka, T. G. L.

2016-09-01

This paper deals with introducing MR dampers to the Train Suspension System for improving the ride comfort of the passengers. This type of suspension system comes under Semi-active suspension system which utilizes the properties of MR fluid to damp the vibrations. In case of high speed trains, the coach body is subjected to vibrations due to vertical displacement, yaw and pitch movements. When the body receives these disturbances from the ground,the transmission of vibrations to the passenger increases which affect the ride comfort. In this work, the equations of motion of suspension system are developed for both conventional passive system and semi-active system and are modelled in Matlab/Simulink and analysis has been carried out. The passive suspension system analysis shows that it is taking more time to damp the vibrations and at the same time the transmissibility of vibrations is more.Introducing MR dampers,vertical and angular displacements of the body are computed and compared. The results show that the introduction of MR dampers into the train suspension system improves ride comfort.

Equilibrium and generators

International Nuclear Information System (INIS)

Balter, H.S.

1994-01-01

This work studies the behaviour of radionuclides when it produce a desintegration activity,decay and the isotopes stable creation. It gives definitions about the equilibrium between activity of parent and activity of the daughter, radioactive decay,isotope stable and transient equilibrium and maxim activity time. Some considerations had been given to generators that permit a disgregation of two radioisotopes in equilibrium and its good performance. Tabs

Pitched Blade Turbine Efficiency at Particle Suspension

Directory of Open Access Journals (Sweden)

D. Ceres

2010-01-01

Full Text Available Mixing suspensions is a very important hydraulic operation. The pitched six-blade turbine is a widely-used axial-flow impeller. This paper deals with effect relative impeller size and particle content on theefficiency of a pitched six-blade turbine at particle suspension. Two pitched six-blade turbines were used in model measurements of just suspension impeller speed. The ratios of the vessel to agitator diameter D/d were 3 and 4.5. The measurements were carried out in a dish-bottomed vessel 300 mm in diameter. The just suspension impeller speeds were measured using an electrochemical method, and were checked visually. A 2.5 % NaCl water solution was used as the liquid phase, and glass particles with four equivalent diameters between 0.18 and 0.89 mmand volumetric concentration from 2.5 % to 40% were usedasthesolid phase. The criterion values πs=Po√Fr'3(d/D7 were calculated from the particle suspension and power consumption measurements. The dependencies of πs on particle content cv show that larger agitators are more efficient for higher particle content.

Chemical Principles Revisited: Chemical Equilibrium.

Science.gov (United States)

Mickey, Charles D.

1980-01-01

Describes: (1) Law of Mass Action; (2) equilibrium constant and ideal behavior; (3) general form of the equilibrium constant; (4) forward and reverse reactions; (5) factors influencing equilibrium; (6) Le Chatelier's principle; (7) effects of temperature, changing concentration, and pressure on equilibrium; and (8) catalysts and equilibrium. (JN)

Thermodynamics of the multicomponent vapor-liquid equilibrium under capillary pressure difference

DEFF Research Database (Denmark)

Shapiro, Alexander; Stenby, Erling Halfdan

2001-01-01

We discuss the two-phase multicomponent equilibrium, provided that the phase pressures are different due to the action of capillary forces. We prove the two general properties of such an equilibrium, which have previously been known for a single-component case, however, to the best of our knowledge......, not for the multicomponent mixtures. The importance is emphasized on the space of the intensive variables P, T and mu (i), where the laws of capillary equilibrium have a simple geometrical interpretation. We formulate thermodynamic problems specific to such an equilibrium, and outline changes to be introduced to common...... algorithms of flash calculations in order to solve these problems. Sample calculations show large variation of the capillary properties of the mixture in the very neighborhood of the phase envelope and the restrictive role of the spinodal surface as a boundary for possible equilibrium states with different...

Suspension for the low frequency facility

CERN Document Server

Cella, G; Di Virgilio, A; Gaddi, A; Viceré, A

2000-01-01

We introduce the working principles of the VIRGO Low Frequency Facility (LFF), whose main aim is the measurement of the thermal noise in the VIRGO suspension system. We evaluate the displacement thermal noise of a mirror, which is an intermediate element of a double pendulum suspension system. This double pendulum will be suspended to the last stage of a VIRGO Super-Attenuator (SA), the prototype VIRGO suspension system being tested at the Pisa section of INFN. In the proposed configuration, we evaluate the spectrum of the thermal noise for different choices of the parameters: based on this study, we comment on the future directions to be undertaken in the LFF experiment.

Network synthesis and parameter optimization for vehicle suspension with inerter

Directory of Open Access Journals (Sweden)

Long Chen

2016-12-01

Full Text Available In order to design a comfortable-oriented vehicle suspension structure, the network synthesis method was utilized to transfer the problem into solving a timing robust control problem and determine the structure of “inerter–spring–damper” suspension. Bilinear Matrix Inequality was utilized to obtain the timing transfer function. Then, the transfer function of suspension system can be physically implemented by passive elements such as spring, damper, and inerter. By analyzing the sensitivity and quantum genetic algorithm, the optimized parameters of inerter–spring–damper suspension were determined. A quarter-car model was established. The performance of the inerter–spring–damper suspension was verified under random input. The simulation results manifested that the dynamic performance of the proposed suspension was enhanced in contrast with traditional suspension. The root mean square of vehicle body acceleration decreases by 18.9%. The inerter–spring–damper suspension can inhibit the vertical vibration within the frequency of 1–3 Hz effectively and enhance the performance of ride comfort significantly.

Adaptive neural networks control for camera stabilization with active suspension system

Directory of Open Access Journals (Sweden)

Feng Zhao

2015-08-01

Full Text Available The camera always suffers from image instability on the moving vehicle due to unintentional vibrations caused by road roughness. This article presents an adaptive neural network approach mixed with linear quadratic regulator control for a quarter-car active suspension system to stabilize the image captured area of the camera. An active suspension system provides extra force through the actuator which allows it to suppress vertical vibration of sprung mass. First, to deal with the road disturbance and the system uncertainties, radial basis function neural network is proposed to construct the map between the state error and the compensation component, which can correct the optimal state-feedback control law. The weights matrix of radial basis function neural network is adaptively tuned online. Then, the closed-loop stability and asymptotic convergence performance is guaranteed by Lyapunov analysis. Finally, the simulation results demonstrate that the proposed controller effectively suppresses the vibration of the camera and enhances the stabilization of the entire camera, where different excitations are considered to validate the system performance.

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

Non-equilibrium properties of Josephson critical current in Nb-based three terminal superconducting tunnel devices

International Nuclear Information System (INIS)

Ammendola, G.; Parlato, L.; Peluso, G.; Pepe, G.

1998-01-01

Tunnel quasi-particle injection into a superconducting film provides useful information on the non-equilibrium state inside the perturbed superconductor as well as on the potential application to electronic devices. Three terminal injector-detector superconducting devices have a long history in non-equilibrium superconductivity. In the recent past non-equilibrium phenomena have attracted again considerable attention because of many superconducting based detectors involve processes substantially non-equilibrium in nature. The possibility of using a stacked double tunnel junction to study the influence of non-equilibrium superconductivity on the Josephson critical current is now considered. An experimental study of the effect of quasi-particle injection on the Josephson current both in steady-state and pulsed experiments down to T=1.2 K is presented using 3 terminal Nb-based stacked double tunnel devices. The feasibility of a new class of particle detectors based on the direct measurement of the change in the Josephson current following the absorption of a X-ray quantum is also discussed in terms of non-equilibrium theories. (orig.)

Measurement of microbic contamination rate in the dispensing process making suspension of barium sulfate powder

International Nuclear Information System (INIS)

Kim, Young Keun; Lee, Yang Sub; Cho, Cheong Chan; Ryu, Meung Sun; Lee, Kyung Sup

2001-01-01

The purpose of this study is to investigate the contamination rate of barium sulfate suspension made in the exposed state in usual circumstances. This study was performed in four university hospital using the contrast media by barium sulfate powder. The specimen were detected at dispensing water, agitator and mixing tank. We also classified the suspension into general bacteria, mycete and Bacillus coli infection. The tap water were used to dispense water in the all hospitals. Bacillus coli were not detected in the all. General bacteria and mycete were not detected in the one specimen, but detected in two specimen over defined value. In the contamination rate of agitator, mixing tank, and the manufactured. Bacillus coli were not detected in all. However, general bacteria and mycete were detected too numberous to count. In conclusion, the refined water must be used in dispensing water in manufacturing suspension. The disinfectant is also used in washing the agitator and mixing tank for sterilization. Hand washing is indispensable to manufacturing suspension for preventing from infection

Determining Quiescent Colloidal Suspension Viscosities Using the Green-Kubo Relation and Image-Based Stress Measurements

Science.gov (United States)

Lin, Neil Y. C.; Bierbaum, Matthew; Cohen, Itai

2017-09-01

By combining confocal microscopy and stress assessment from local structural anisotropy, we directly measure stresses in 3D quiescent colloidal liquids. Our noninvasive and nonperturbative method allows us to measure forces ≲50 fN with a small and tunable probing volume, enabling us to resolve the stress fluctuations arising from particle thermal motions. We use the Green-Kubo relation to relate these measured stress fluctuations to the bulk Brownian viscosity at different volume fractions, comparing against simulations and conventional rheometry measurements. We find that the Green-Kubo analysis gives excellent agreement with these prior results, suggesting that similar methods could be applied to investigations of local flow properties in many poorly understood far-from-equilibrium systems, including suspensions that are glassy, strongly sheared, or highly confined.

Approach to equilibrium in a pure superconductor. The relaxation of the Cooper pair density

Energy Technology Data Exchange (ETDEWEB)

Schid, A

1968-01-01

Electron-phonon and electron-electron collisions are the processes which determine the relaxation time r/sub R/ of the Cooper pair density. The case is considered for which the deviation of the pair density from equilibrium is small and where the equilibrium state is homogeneous. Starting from the Eliashberg equation one is able to reduce the problem to a quadrature once the equilibrium Green functions are known.

49 CFR 393.207 - Suspension systems.

Science.gov (United States)

2010-10-01

... braking system. The vehicle shall be level (not tilting to the left or right). Air leakage shall not be... 49 Transportation 5 2010-10-01 2010-10-01 false Suspension systems. 393.207 Section 393.207... NECESSARY FOR SAFE OPERATION Frames, Cab and Body Components, Wheels, Steering, and Suspension Systems § 393...

Two-proton correlation functions for equilibrium and non-equilibrium emission

International Nuclear Information System (INIS)

Gong, W.G.; Gelbke, C.K.; Carlin, N.; De Souza, R.T.; Kim, Y.D.; Lynch, W.G.; Murakami, T.; Poggi, G.; Sanderson, D.; Tsang, M.B.; Xu, H.M.; Michigan State Univ., East Lansing; Fields, D.E.; Kwiatkowski, K.; Planeta, R.; Viola, V.E. Jr.; Yennello, S.J.; Indiana Univ., Bloomington; Indiana Univ., Bloomington; Pratt, S.

1990-01-01

Two-proton correlation functions are compared for equilibrium and non-equilibrium emission processes investigated, respectively, in ''reverse kinematics'' for the reactions 129 Xe+ 27 Al and 129 Xe+ 122 Sn at E/A=31 MeV and in ''forward kinematics'' for the reaction 14 N+ 197 Au at E/A=75 MeV. Observed differences in the shapes of the correlation functions are understood in terms of the different time scales for equilibrium and preequilibrium emission. Transverse and longitudinal correlation functions are very similar. (orig.)

Non-equilibrium Dynamics, Thermalization and Entropy Production

International Nuclear Information System (INIS)

Hinrichsen, Haye; Janotta, Peter; Gogolin, Christian

2011-01-01

This paper addresses fundamental aspects of statistical mechanics such as the motivation of a classical state space with spontaneous transitions, the meaning of non-equilibrium in the context of thermalization, and the justification of these concepts from the quantum-mechanical point of view. After an introductory part we focus on the problem of entropy production in non-equilibrium systems. In particular, the generally accepted formula for entropy production in the environment is analyzed from a critical perspective. It is shown that this formula is only valid in the limit of separated time scales of the system's and the environmental degrees of freedom. Finally, we present an alternative simple proof of the fluctuation theorem.

MHD equilibrium with toroidal rotation

International Nuclear Information System (INIS)

Li, J.

1987-03-01

The present work attempts to formulate the equilibrium of axisymmetric plasma with purely toroidal flow within ideal MHD theory. In general, the inertial term Rho(v.Del)v caused by plasma flow is so complicated that the equilibrium equation is completely different from the Grad-Shafranov equation. However, in the case of purely toroidal flow the equilibrium equation can be simplified so that it resembles the Grad-Shafranov equation. Generally one arbitrary two-variable functions and two arbitrary single variable functions, instead of only four single-variable functions, are allowed in the new equilibrium equations. Also, the boundary conditions of the rotating (with purely toroidal fluid flow, static - without any fluid flow) equilibrium are the same as those of the static equilibrium. So numerically one can calculate the rotating equilibrium as a static equilibrium. (author)

36 CFR 25.3 - Supervision; suspensions.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Supervision; suspensions. 25.3 Section 25.3 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL MILITARY PARKS; LICENSED GUIDE SERVICE REGULATIONS § 25.3 Supervision; suspensions. (a) The guide service will operate under the direction...

Rheology of dense suspensions of non colloidal particles

Directory of Open Access Journals (Sweden)

Guazzelli Élisabeth

2017-01-01

Full Text Available Dense suspensions are materials with broad applications both in industrial processes (e.g. waste disposal, concrete, drilling muds, metalworking chip transport, and food processing and in natural phenomena (e.g. flows of slurries, debris, and lava. Despite its long research history and its practical relevance, the mechanics of dense suspensions remain poorly understood. The major difficulty is that the grains interact both by hydrodynamic interactions through the liquid and by mechanical contact. These systems thus belong to an intermediate regime between pure suspensions and granular flows. We show that we can unify suspension and granular rheology under a common framework by transferring the frictional approach of dry granular media to wet suspensions of spherical particles. We also discuss non-Newtonian behavior such as normal-stress differences and shear-induced migration. Beyond the classical problem of dense suspension of hard spheres which is far from being completely resolved, there are also entirely novel avenues of study concerning more complex mixtures of particles and fluids such as those involving other types of particles (e.g. fibers or non-Newtonian fluids that we will also address.

A tightly coupled non-equilibrium model for inductively coupled radio-frequency plasmas

International Nuclear Information System (INIS)

Munafò, A.; Alfuhaid, S. A.; Panesi, M.; Cambier, J.-L.

2015-01-01

The objective of the present work is the development of a tightly coupled magneto-hydrodynamic model for inductively coupled radio-frequency plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State approach. A multi-temperature formulation is used to account for thermal non-equilibrium between translation of heavy-particles and vibration of molecules. Excited electronic states of atoms are instead treated as separate pseudo-species, allowing for non-Boltzmann distributions of their populations. Free-electrons are assumed Maxwellian at their own temperature. The governing equations for the electro-magnetic field and the gas properties (e.g., chemical composition and temperatures) are written as a coupled system of time-dependent conservation laws. Steady-state solutions are obtained by means of an implicit Finite Volume method. The results obtained in both LTE and NLTE conditions over a broad spectrum of operating conditions demonstrate the robustness of the proposed coupled numerical method. The analysis of chemical composition and temperature distributions along the torch radius shows that: (i) the use of the LTE assumption may lead to an inaccurate prediction of the thermo-chemical state of the gas, and (ii) non-equilibrium phenomena play a significant role close the walls, due to the combined effects of Ohmic heating and macroscopic gradients

Rheological Properties of Aqueous Nanometric Alumina Suspensions

Energy Technology Data Exchange (ETDEWEB)

Li, Chuanping [Iowa State Univ., Ames, IA (United States)

2004-01-01

Colloidal processing is an effective and reliable approach in the fabrication of the advanced ceramic products. Successful colloidal processing of fine ceramic powders requires accurate control of the rheological properties. The accurate control relies on the understanding the influences of various colloidal parameters on the rheological properties. Almost all research done on the rheology paid less attention to the interactions of particle and solvent. However, the interactions of the particles are usually built up through the media in which the particles are suspended. Therefore, interactions of the particle with the media, the adsorbed layers on the particle surface, and chemical and physical properties of media themselves must influence the rheology of the suspension, especially for the dense suspensions containing nanosized particles. Relatively little research work has been reported in this area. This thesis addresses the rheological properties of nanometric alumina aqueous suspensions, and paying more attention to the interactions between particle and solvent, which in turn influence the particle-particle interactions. Dense nanometric alumina aqueous suspensions with low viscosity were achieved by environmentally-benign fructose additives. The rheology of nanometric alumina aqueous suspensions and its variation with the particle volume fraction and concentration of fructose were explored by rheometry. The adsorptions of solute (fructose) and solvent (water) on the nanometric alumina particle surfaces were measured and analyzed by TG/DSC, TOC, and NMR techniques. The mobility of water molecules in the suspensions and its variation with particle volume fractions and fructose additive were determined by the ¹⁷O NMR relaxation method. The interactions between the nanometric alumina particles in water and fructose solutions were investigated by AFM. The results indicated that a large number of water layers were physically bound on the particles

Well-dispersed gold nanowire suspension for assembly application

International Nuclear Information System (INIS)

Xu Cailing; Zhang Li; Zhang Haoli; Li Hulin

2005-01-01

A method for fabricating well-dispersed nanowire suspension has been demonstrated in the paper. Thin gold nanowires were prepared by template synthesis, and then functionalized with sulphonate group-terminated thiols before suspended in different solvents. The degree of aggregation of the obtained suspension was evaluated with transmission electron microscopy (TEM) and UV-vis spectroscopy. It was found that the degree of aggregation was predominated by the solvents, and the best degree of dispersion was obtained when isopropyl alcohol (IPA) was used as the solvent. The gold nanowires from the suspension can be selectively assembled onto chemically patterned substrates. This well-dispersed nanowire suspension is potentially useful for fabricating novel nanodevices

Cross sections for charge change in argon and equilibrium charge states of 3.5 MeV/amu uranium ions passing through argon and carbon targets

International Nuclear Information System (INIS)

Perumal, A.N.; Horvat, V.; Watson, R.L.; Peng, Y.; Fruchey, K.S.

2005-01-01

Cross sections for single and multiple electron capture and loss were measured for 3.5 MeV/amu uranium ions, traveling in argon gas, as a function of incident charge state. Multiple electron loss in single collisions was found to contribute significantly to the total loss cross section. The measured cross sections were used to determine the average equilibrium charge in argon by three different methods. The resulting charges were in good agreement with each other and with the effective charge calculated from stopping powers. In order to investigate the gas-solid (density) effect on the average equilibrium charge, the charge distributions of 3.5 MeV/amu uranium ions emerging from carbon foils of different thicknesses were measured. It was found that the average equilibrium charge of the uranium ions emerging from the solid is 41% larger than that of the uranium ions emerging from the gas. The energy dependences of the average equilibrium charges for uranium ions exiting carbon and argon targets were examined by combining the present results with previous results of other investigators and compared with the predictions of a semiempirical formula developed recently by Schiwietz and Grande

Disassembly of Faceted Macrosteps in the Step Droplet Zone in Non-Equilibrium Steady State

Directory of Open Access Journals (Sweden)

Noriko Akutsu

2017-02-01

Full Text Available A Wulff figure—the polar graph of the surface tension of a crystal—with a discontinuity was calculated by applying the density matrix renormalization group method to the p-RSOS model, a restricted solid-on-solid model with a point-contact-type step–step attraction. In the step droplet zone in this model, the surface tension is discontinuous around the (111 surface and continuous around the (001 surface. The vicinal surface of 4H-SiC crystal in a Si–Cr–C solution is thought to be in the step droplet zone. The dependence of the vicinal surface growth rate and the macrostep size 〈 n 〉 on the driving force Δ μ for a typical state in the step droplet zone in non-equilibrium steady state was calculated using the Monte Carlo method. In contrast to the known step bunching phenomenon, the size of the macrostep was found to decrease with increasing driving force. The detachment of elementary steps from a macrostep was investigated, and it was found that 〈 n 〉 satisfies a scaling function. Moreover, kinetic roughening was observed for | Δ μ | > Δ μ R , where Δ μ R is the crossover driving force above which the macrostep disappears.

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.

Rheological properties of purified illite clays in glycerol/water suspensions

Science.gov (United States)

Dusenkova, I.; Malers, J.; Berzina-Cimdina, L.

2015-04-01

There are many studies about rheological properties of clay-water suspensions, but no published investigations about clay-glycerol suspensions. In this work apparent viscosity of previously purified illite containing clay fraction clay minerals were almost totally removed by centrifugation. All obtained suspensions behaved as shear-thinning fluids with multiple times higher viscosity than pure glycerol/water solutions. Reduction of clay fraction concentration by 5% decreased the apparent viscosity of 50% glycerol/water suspensions approximately 5 times. There was basically no difference in apparent viscosity between all four 50% glycerol/water suspensions, but in 90% glycerol/water suspensions samples from Iecava deposit showed slightly higher apparent viscosity, which could be affected by the particle size distribution.

Preview based control of suspension systems for commercial vehicles

NARCIS (Netherlands)

Muijderman, J.H.E.A.; Kok, J.J.; Huisman, R.G.M.; Veldpaus, F.E.; van Heck, J.G.A.M.

1999-01-01

An active suspension with preview is developed for the rear axle of a commercial vehicle. The obtained improvements are promising and justify further investigation of the more feasible semi-active suspensions with preview. The inherent non-linearity of semi-active suspensions with switching shock

Research on Dynamic Optimization for Road-friendly Vehicle Suspension

Directory of Open Access Journals (Sweden)

Lu Yongjie

2014-10-01

Full Text Available The heavy vehicle brings large dynamic loads to the road surface, which would reduce vehicle ride comfort and shorten road service life. The structure characteristic of heavy vehicle suspension has a significant impact on vehicle performance. Based on the D'Alembert principle, the dynamics models of independent and integral balanced suspension are proposed considering mass and inertia of balancing rod. The sprung mass acceleration and the tire dynamic force for two kinds of balanced suspension and the traditional quarter vehicle model are compared in frequency-domain and time-domain respectively. It is concluded that a quarter vehicle model simplified for balanced suspension could be used to evaluate the ride comfort of vehicle well, but it has some limitations in assessing the vehicle road-friendliness. Then, the sprung mass acceleration and the road damage coefficients are also analyzed under different vehicle design and running parameters at detail. Some conclusions are obtained: low suspension stiffness, high suspension damping and low tire stiffness are all favorable to improve vehicle performance; there is a saturation range of suspension damping enhancing vehicle performance; improving the road surface roughness and avoiding the no-load running are two effective methods to accomplish the better ride comfort and road-friendliness. The suspension stiffness and damping parameters are chosen for optimal parameters matching of road friendliness based on the approximation optimization method.

Numerical study of suspensions of deformable particles.

Science.gov (United States)

Brandt, Luca; Rosti, Marco Edoardo

2017-11-01

We consider a model non-Newtonian fluid consisting of a suspension of deformable particles in a Newtonian solvent. Einstein showed in his pioneering work that the relative increase in effective viscosity is a linear function of the particle volume fraction for dilute suspensions of rigid particles. Inertia has been shown to introduce deviations from the behaviour predicted by the different empirical fits, an effect that can be related to an increase of the effective volume fraction. We here focus on the effect of elasticity, i.e. visco-elastic deformable particles. To tackle the problem at hand, we perform three-dimensional Direct Numerical Simulation of a plane Couette flow with a suspension of neutrally buoyant deformable viscous hyper-elastic particles. We show that elasticity produces a shear-thinning effect in elastic suspensions (in comparison to rigid ones) and that it can be understood in terms of a reduction of the effective volume fraction of the suspension. The deformation modifies the particle motion reducing the level of mutual interaction. Normal stress differences will also be considered. European Research Council, Grant No. ERC-2013-CoG- 616186, TRITOS; SNIC (the Swedish National Infrastructure for Computing).

Minimally invasive brow suspension for facial paralysis.

Science.gov (United States)

Costantino, Peter D; Hiltzik, David H; Moche, Jason; Preminger, Aviva

2003-01-01

To report a new technique for unilateral brow suspension for facial paralysis that is minimally invasive, limits supraciliary scar formation, does not require specialized endoscopic equipment or expertise, and has proved to be equal to direct brow suspension in durability and symmetry. Retrospective survey of a case series of 23 patients between January 1997 and December 2000. Metropolitan tertiary care center. Patients with head and neck tumors and brow ptosis caused by facial nerve paralysis. The results of the procedure were determined using the following 3-tier rating system: outstanding (excellent elevation and symmetry); acceptable (good elevation and fair symmetry); and unacceptable (loss of elevation). The results were considered outstanding in 12 patients, acceptable in 9 patients, and unacceptable in only 1 patient. One patient developed a hematoma, and 1 patient required a secondary adjustment. The technique has proved to be superior to standard brow suspension procedures with regard to scar formation and equal with respect to facial symmetry and suspension. These results have caused us to abandon direct brow suspension and to use this minimally invasive method in all cases of brow ptosis due to facial paralysis.

BGK-type models in strong reaction and kinetic chemical equilibrium regimes

International Nuclear Information System (INIS)

Monaco, R; Bianchi, M Pandolfi; Soares, A J

2005-01-01

A BGK-type procedure is applied to multi-component gases undergoing chemical reactions of bimolecular type. The relaxation process towards local Maxwellians, depending on mass and numerical densities of each species as well as common velocity and temperature, is investigated in two different cases with respect to chemical regimes. These cases are related to the strong reaction regime characterized by slow reactions, and to the kinetic chemical equilibrium regime where fast reactions take place. The consistency properties of both models are stated in detail. The trend to equilibrium is numerically tested and comparisons for the two regimes are performed within the hydrogen-air and carbon-oxygen reaction mechanism. In the spatial homogeneous case, it is also shown that the thermodynamical equilibrium of the models recovers satisfactorily the asymptotic equilibrium solutions to the reactive Euler equations

Non-equilibrium Economics

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.

Elements of non-equilibrium (ℎ, k)-dynamics at zero and finite temperatures

International Nuclear Information System (INIS)

Golubeva, O.N.; Sukhanov, A.D.

2011-01-01

We suggest a method which allows developing some elements of non-equilibrium (ℎ, k)-dynamics without use of Schroedinger equation. It is based on the generalization pf Fokker-Planck and Hamilton-Jacobi equations. Sequential considering of stochastic influence of vacuum is realized in the quantum heat bath model. We show that at the presence of quantum-thermal diffusion non-equilibrium wave functions describe the process of nearing to generalized state of thermal equilibrium at zero and finite temperatures. They can be used as a ground for universal description of transport phenomena

Core performance of equilibrium fast reactors for different coolant materials and fuel types

International Nuclear Information System (INIS)

Mizutani, Akihiko; Sekimoto, Hiroshi

1998-01-01

Parametric studies with several coolant and fuel materials in the equilibrium state are performed for fast reactors in which natural uranium is fed and all of the actinides are confined. Sodium, sodium-potassium, lead, lead-bismuth and helium coolant materials, and oxide, nitride and metal fuels are employed to compare the neutronic characteristics in the equilibrium state. As to the criticality performance, sodium-potassium shows the best performance among the liquid metal coolants and the metallic fuel indicates the best performance

Ion exchange equilibrium constants

CERN Document Server

Marcus, Y

2013-01-01

Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and

Colloidal dispersions in external fields: from equilibrium to non-equilibrium

Science.gov (United States)

Lowen, Hartmut

2010-03-01

Dispersions of colloidal particles are excellent model systems of classical statistical mechanics in order to understand the principles of self-organization processes. Using an external field (e.g. electric or magnetic field) the effective interaction between the colloidal particles can be tailored and the system can be brought into non-equilibrium in a controlled way. Glass formation after an ultrafast quench in a two-dimensional superparamagnetic binary colloidal mixture [1,2] will be discussed as well as lane [3,4,5,6,7] and band [8] formation in mixtures of charged suspensions and dusty plasmas driven by an electric field. [4pt] References:[0pt] [1] L. Assoud, F. Ebert, P. Keim, R. Messina, G. Maret, H. Lowen, Phys. Rev. Letters 102, 238301 (2009). [0pt] [2] L. Assoud, F. Ebert, P. Keim, R. Messina, G. Maret, H. Lowen, J. Phys.: Condensed Matter 21, 464114 (2009). [0pt] [3] J. Dzubiella, G. P. Hoffmann, H. Lowen, Phys. Rev. E 65, 021402 (1-8) (2002). [0pt] [4] M. E. Leunissen, C. G. Christova, A. P. Hynninen, C. P. Royall, A. I. Campbell, A. Imhof, M. Dijkstra, R. van Roij, A. van Blaaderen, Nature 437, 235 (2005). [0pt] [5] M. Rex, H. Lowen, Phys. Rev. E 75, 051402 (2007). [0pt] [6] M. Rex, C. P. Royall, A. van Blaaderen, H. Lowen, Lane formation in driven colloidal mixtures: is it continuous or discontinuous?, http://arxiv.org/abs/0812.0908 [0pt] [7] K. R. Sutterlin, A. Wysocki, A. V. Ivlev, C. Rath, H. M. Thomas, M. Rubin-Zuzic, W. J. Goedheer, V. E. Fortov, A. M. Lipaev, V. I. Molotkov, O. F. Petrov, G. E. Morfill, H. Lowen, Phys. Rev. Letters 102, 085003 (2009). [0pt] [8] A. Wysocki, H. Lowen, Phys. Rev. E 79, 041408 (2009).

Forces and energy dissipation in inhomogeneous non-equilibrium superconductors

International Nuclear Information System (INIS)