The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
George T. Detitta - One of the best experts on this subject based on the ideXlab platform.
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Rate of water Equilibration in vapor-diffusion crystallization: dependence on the residual pressure of air in the vapor space.
Acta Crystallographica Section D-biological Crystallography, 1995Co-Authors: George T. Detitta, J. R. LuftAbstract:The kinetics of water Equilibration in vapor-diffusion crystallization experiments are sensitive to the residual pressure of air in the vapor chamber. Experiments with sitting droplets of 10%(w/v) PEG, allowed to equilibrate with reservoirs of 20%(w/v) PEG, were conducted at pressures ranging from 80 to 760 mm Hg. Equilibrations were interrupted after one, four, five and seven days to assess their progress. Even down to the lowest pressures examined it was found that a decrease in pressure leads to an increase in the rate of Equilibration. The residual pressure of air in the vapor chamber can be varied to tailor the time course of Equilibration in macromolecular crystal growth experiments.
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Chaperone salts, polyethylene glycol and rates of Equilibration in vapor-diffusion crystallization.
Acta Crystallographica Section D Biological Crystallography, 1995Co-Authors: Joseph R. Luft, George T. DetittaAbstract:The kinetics of water-vapor Equilibration in macromolecular crystallization were investigated for sitting droplets of aqueous polyethylene glycol (PEG) 8000 as a function of concentration. Equilibrations, set up with initial concentrations of PEG in the droplet at half those in the reservoir, were very slow for concentrations of relevance to the macromolecular crystal growth problem. At 301 K, 24 µl droplets at initial concentrations of 2.5, 5.0 and 7.5%(w/v) PEG require 12, 5, and 3 weeks to reach equilibrium, respectively. On the other hand, the addition of modest quantities of sodium chloride to both droplet and reservoir increases the rate of Equilibration for aqueous PEG sitting droplets significantly. At 293 K, droplets with initial volumes of 24 µl and PEG concentrations of 5%(w/v) require 12 weeks to reach equilibrium, while droplets of the same volume and initial concentrations of 5%(w/v) PEG and 200 mM NaCI require less than two weeks to reach equilibrium. The slow vapor-diffusion Equilibrations of pure PEG solutions, and the subsequent increase in these rates with colligative agents such as salt, are a consequence of the non-ideality of aqueous PEG solutions. These results are of interest both from a practical and a theoretical viewpoint. They underscore the importance of kinetic factors in macromolecular crystal growth, help to explain apparent inconsistencies of outcome in PEG-mediated crystallizations, and yield another methodology for the optimization of crystal growth conditions, namely the control of the kinetics of Equilibration using colligative agents.
Sergey V. Dmitriev - One of the best experts on this subject based on the ideXlab platform.
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Equilibration of sinusoidal modulation of temperature in linear and nonlinear chains
Physical Review E, 2020Co-Authors: Elena A. Korznikova, Vitaly A. Kuzkin, Anton M. Krivtsov, Daxing Xiong, Vakhid A. Gani, Aleksey Kudreyko, Sergey V. DmitrievAbstract:The Equilibration of sinusoidally modulated distribution of the kinetic temperature is analyzed in the $\ensuremath{\beta}$-Fermi-Pasta-Ulam-Tsingou chain with different degrees of nonlinearity and for different wavelengths of temperature modulation. Two different types of initial conditions are used to show that either one gives the same result as the number of realizations increases and that the initial conditions that are closer to the state of thermal equilibrium give faster convergence. The kinetics of temperature Equilibration is monitored and compared to the analytical solution available for the linear chain in the continuum limit. The transition from ballistic to diffusive thermal conductivity with an increase in the degree of anharmonicity is shown. In the ballistic case, the energy Equilibration has an oscillatory character with an amplitude decreasing in time, and in the diffusive case, it is monotonous in time. For smaller wavelength of temperature modulation, the oscillatory character of temperature Equilibration remains for a larger degree of anharmonicity. For a given wavelength of temperature modulation, there is such a value of the anharmonicity parameter at which the temperature Equilibration occurs most rapidly.
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Equilibration of sinusoidal modulation of temperature in linear and nonlinear chains.
Physical review. E, 2020Co-Authors: Elena A. Korznikova, Vitaly A. Kuzkin, Anton M. Krivtsov, Daxing Xiong, Vakhid A. Gani, Aleksey Kudreyko, Sergey V. DmitrievAbstract:The Equilibration of sinusoidally modulated distribution of the kinetic temperature is analyzed in the β-Fermi-Pasta-Ulam-Tsingou chain with different degrees of nonlinearity and for different wavelengths of temperature modulation. Two different types of initial conditions are used to show that either one gives the same result as the number of realizations increases and that the initial conditions that are closer to the state of thermal equilibrium give faster convergence. The kinetics of temperature Equilibration is monitored and compared to the analytical solution available for the linear chain in the continuum limit. The transition from ballistic to diffusive thermal conductivity with an increase in the degree of anharmonicity is shown. In the ballistic case, the energy Equilibration has an oscillatory character with an amplitude decreasing in time, and in the diffusive case, it is monotonous in time. For smaller wavelength of temperature modulation, the oscillatory character of temperature Equilibration remains for a larger degree of anharmonicity. For a given wavelength of temperature modulation, there is such a value of the anharmonicity parameter at which the temperature Equilibration occurs most rapidly.
J. R. Luft - One of the best experts on this subject based on the ideXlab platform.
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Rate of water Equilibration in vapor-diffusion crystallization: dependence on the residual pressure of air in the vapor space.
Acta Crystallographica Section D-biological Crystallography, 1995Co-Authors: George T. Detitta, J. R. LuftAbstract:The kinetics of water Equilibration in vapor-diffusion crystallization experiments are sensitive to the residual pressure of air in the vapor chamber. Experiments with sitting droplets of 10%(w/v) PEG, allowed to equilibrate with reservoirs of 20%(w/v) PEG, were conducted at pressures ranging from 80 to 760 mm Hg. Equilibrations were interrupted after one, four, five and seven days to assess their progress. Even down to the lowest pressures examined it was found that a decrease in pressure leads to an increase in the rate of Equilibration. The residual pressure of air in the vapor chamber can be varied to tailor the time course of Equilibration in macromolecular crystal growth experiments.
Elena A. Korznikova - One of the best experts on this subject based on the ideXlab platform.
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Equilibration of sinusoidal modulation of temperature in linear and nonlinear chains
Physical Review E, 2020Co-Authors: Elena A. Korznikova, Vitaly A. Kuzkin, Anton M. Krivtsov, Daxing Xiong, Vakhid A. Gani, Aleksey Kudreyko, Sergey V. DmitrievAbstract:The Equilibration of sinusoidally modulated distribution of the kinetic temperature is analyzed in the $\ensuremath{\beta}$-Fermi-Pasta-Ulam-Tsingou chain with different degrees of nonlinearity and for different wavelengths of temperature modulation. Two different types of initial conditions are used to show that either one gives the same result as the number of realizations increases and that the initial conditions that are closer to the state of thermal equilibrium give faster convergence. The kinetics of temperature Equilibration is monitored and compared to the analytical solution available for the linear chain in the continuum limit. The transition from ballistic to diffusive thermal conductivity with an increase in the degree of anharmonicity is shown. In the ballistic case, the energy Equilibration has an oscillatory character with an amplitude decreasing in time, and in the diffusive case, it is monotonous in time. For smaller wavelength of temperature modulation, the oscillatory character of temperature Equilibration remains for a larger degree of anharmonicity. For a given wavelength of temperature modulation, there is such a value of the anharmonicity parameter at which the temperature Equilibration occurs most rapidly.
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Equilibration of sinusoidal modulation of temperature in linear and nonlinear chains.
Physical review. E, 2020Co-Authors: Elena A. Korznikova, Vitaly A. Kuzkin, Anton M. Krivtsov, Daxing Xiong, Vakhid A. Gani, Aleksey Kudreyko, Sergey V. DmitrievAbstract:The Equilibration of sinusoidally modulated distribution of the kinetic temperature is analyzed in the β-Fermi-Pasta-Ulam-Tsingou chain with different degrees of nonlinearity and for different wavelengths of temperature modulation. Two different types of initial conditions are used to show that either one gives the same result as the number of realizations increases and that the initial conditions that are closer to the state of thermal equilibrium give faster convergence. The kinetics of temperature Equilibration is monitored and compared to the analytical solution available for the linear chain in the continuum limit. The transition from ballistic to diffusive thermal conductivity with an increase in the degree of anharmonicity is shown. In the ballistic case, the energy Equilibration has an oscillatory character with an amplitude decreasing in time, and in the diffusive case, it is monotonous in time. For smaller wavelength of temperature modulation, the oscillatory character of temperature Equilibration remains for a larger degree of anharmonicity. For a given wavelength of temperature modulation, there is such a value of the anharmonicity parameter at which the temperature Equilibration occurs most rapidly.
Xin-nian Wang - One of the best experts on this subject based on the ideXlab platform.
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Approach to Parton Equilibration
Nuclear Physics, 1995Co-Authors: Xin-nian WangAbstract:Abstract Perturbative QCD-based models of parton production and Equilibration in ultrarelativistic heavy ion collisions are reviewed with an emphasis on the treatment of quantum interference effects. Uncertainties in the initial parton production and their effects on later parton Equilibration are considered. Probes of early parton dynamics are also discussed.
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Parton Equilibration at RHIC and LHC
Nuclear Physics A, 1994Co-Authors: Tamás S. Biró, Berndt Müller, Markus H. Thoma, Xin-nian WangAbstract:Abstract The processes leading to phase space Equilibration of parton distributions in ultrarelativistic heavy ion collisions are investigated. A set of rate equations describing the chemical Equilibration of quarks and gluons based on perturbative QCD including medium effects are derived, and their consequences for parton Equilibration at RHIC and LHC are discussed.
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Parton Equilibration in relativistic heavy ion collisions
Physical review. C Nuclear physics, 1993Co-Authors: Tamás S. Biró, Berndt Müller, Markus H. Thoma, Van Doorn E, Xin-nian WangAbstract:We investigate the processes leading to phase-space Equilibration of parton distributions in nuclear interactions at collider energies. We derive a set of rate equations describing the chemical Equilibration of gluons and quarks including medium effects on the relevant QCD transport coefficients, and discuss their consequences for parton Equilibration in heavy ion collisions.
