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Poissonian reducibility and thermal scaling within the lattice gas model and molecular dynamics model  [PDF]
Y. G. Ma
Physics , 2000,
Abstract: The emission of clusters in the nuclear disassembly is investigated within the framework of isospin dependent lattice gas model and classical molecular dynamics model. As observed in the recent experimental data, it is found that the emission of individual cluster is poissonian and thermal scaling is observed in the linear Arrhenius plots made from the average multiplicity of each cluster. The mass, isotope and charge dependent "emission barriers" are extracted from the slopes of the Arrhenius plots and their possible physical implications are investigated.
Z-dependent Barriers in Multifragmentation from Poissonian Reducibility and Thermal Scaling  [PDF]
L. Beaulieu,L. Phair,L. G. Moretto,G. J. Wozniak
Physics , 1998, DOI: 10.1103/PhysRevLett.81.770
Abstract: We explore the natural limit of binomial reducibility in nuclear multifragmentation by constructing excitation functions for intermediate mass fragments (IMF) of a given element Z. The resulting multiplicity distributions for each window of transverse energy are Poissonian. Thermal scaling is observed in the linear Arrhenius plots made from the average multiplicity of each element. ``Emission barriers'' are extracted from the slopes of the Arrhenius plots and their possible origin is discussed.
Statistical Interpretation of Joint Multiplicity Distributions of Neutrons and Charged Particles  [PDF]
J. Toke,D. K. Agnihotri,W. Skulski,W. U. Schroeder
Physics , 1999, DOI: 10.1103/PhysRevC.63.024604
Abstract: Experimental joint multiplicity distributions of neutrons and charged particles emitted in complex nuclear reactions provide an important test of theoretical models. The method is applied to test three different theoretical models of nuclear multi-fragmentation, two of which fail the test. The measurement of neutrons is decisive in distinguishing between the Berlin and Copenhagen models of nuclear multi-fragmentation and challenges the interpretation of pseudo- Arrhenius plots. Statistical-model evaporation calculations with GEMINI give a good reproduction first and second moments of the experimental multiplicity correlations.
Reducibility of Dupin submanifolds  [PDF]
Marcos Dajczer,Luis A. Florit,Ruy Tojeiro
Mathematics , 2004,
Abstract: We introduce the notion of weak reduciblity for Dupin submanifolds with arbitrary codimension. We give a complete characterization of all weakly reducible Dupin submanifolds, as a consequence of a general result on a broader class of Euclidean submanifolds. As a main application, we derive an explicit recursive procedure to generate all holonomic Dupin submanifolds in terms of solutions of completely integrable systems of linear partial differential equations of first order. We obtain several additional results on Dupin submanifolds.
Life time of resonances in transport simulations  [PDF]
Stefan Leupold
Physics , 2000, DOI: 10.1016/S0375-9474(01)01097-1
Abstract: We calculate the life time of a resonance in our recently developed framework for a test-particle description of transport processes for states with continuous mass spectra. The result differs from the expression commonly used in transport simulations but agrees with the one derived by Danielewicz and Pratt relating the life time to the scattering phase shift.
Development of a Novel Method for in vivo Determination of Activation Energy of Glucose Transport Across S. cerevisiae Cellular Membranes. A Biosensor-like Approach  [PDF]
Diego J. Kormes,Eduardo Cortón
Sensors , 2009, DOI: 10.3390/s90301599
Abstract: Whereas biosensors have been usually proposed as analytical tools, used to investigate the surrounding media pursuing an analytical answer, we have used a biosensor-like device to characterize the microbial cells immobilized on it. We have studied the kinetics of transport and degradation of glucose at different concentrations and temperatures. When glucose concentrations of 15 and 1.5 mM were assayed, calculated activation energies were 25.2 and 18.4 kcal mol-1, respectively, in good agreement with previously published data. The opportunity and convenience of using Arrhenius plots to estimate the activation energy in metabolic-related processes is also discussed.
Degradation kinetics of benzyl nicotinate in aqueous solution  [cached]
Mbah C
Indian Journal of Pharmaceutical Sciences , 2010,
Abstract: The degradation of benzyl nicotinate in aqueous solution over a pH range of 2.0-10.0 at 50±0.2 o was studied. The degradation was determined by high performance liquid chromatography. The degradation was observed to follow apparent first-order rate kinetics and the rate constant for the decomposition at 25 o was estimated by extrapolation. The reaction was shown to be hydroxide ion catalyzed and the Arrhenius plots showed the temperature dependence of benzyl nicotinate degradation. A significant increase in the stability of benzyl nicotinate was observed when glycerol or polyethylene glycol 400 was incorporated into the aqueous solution.
Thermo-oxidative stability of waterborne polyurethanes with catalysts of different selectivity evaluated by non-isothermal thermogravimetry
Journal of the Serbian Chemical Society , 2007,
Abstract: Thermogravimetry was used for the evaluation of the thermo-oxidative stability of waterborne polyurethanes (wbPUR) containing catalysts of different selectivity. From Arrhenius plots, activation energies of between 50 and 120 kJ mol-1 for wbPUR were determined, depending on the temperature interval, selectivity of the catalyst and degree of degradation. Waterborne polyurethanes without catalyst showed lower thermal stability than waterborne polyurethanes with catalysts of different selectivity. Non-isothermal thermogravimetry indicated the presence of different degradation processes and enabled the kinetics parameters at higher degrees of degradation to be evaluated.
Monte Carlo simulations of the L10 long-range order relaxation in dimensionally reduced systems  [PDF]
Mohammed Allalen,Tarik Mehaddene,Hamid Bouzar
Physics , 2007, DOI: 10.1088/0953-8984/19/3/036218
Abstract: Monte Carlo simulations have been performed to investigate the relaxation of the L10 long-range order in dimensionally reduced systems. The effect of the number of (001)-type monatomic layers and of the pair interaction energies on these kinetics has been examined. The vacancy migration energies have been deduced from the Arrhenius plots of the relaxation times. A substantial increase in the migration energy for small film thickness is observed. The results agree with previous Monte Carlo simulations and with recent experimental results in L1_0 thin films and multilayers.
An energy landscape model for glass forming liquids in three dimensions  [PDF]
Ulf R. Pedersen,Tina Hecksher,Jeppe C. Dyre,Thomas B. Schr?der
Physics , 2005, DOI: 10.1016/j.jnoncrysol.2006.03.127
Abstract: We present a three-dimensional lattice-gas model with trivial thermodynamics, but nontrivial dynamics. The model is characterized by each particle having its own random energy landscape. The equilibrium dynamics of the model were investigated by continuous time Monte Carlo simulations at two different densities at several temperatures. At high densities and low temperatures the model captures the important characteristics of viscous liquid dynamics. We thus observe non-exponential relaxation in the self part of the density auto-correlation function, and fragility plots of the self-diffusion constant and relaxation times show non-Arrhenius behavior.
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