We provide a microscopic calculation of neutron-proton and proton-proton cross sections in symmetric nuclear matter at various densities, using the Brueckner Hartree-Fock approximation scheme with the Argonne Va4 pote...We provide a microscopic calculation of neutron-proton and proton-proton cross sections in symmetric nuclear matter at various densities, using the Brueckner Hartree-Fock approximation scheme with the Argonne Va4 potential including the contribution of microscopic three-body force. We investigate separately the effects of three-body force on the effective mass and on the scattering amplitude. In the present calculation, the rearrangement contribution of three-body force is considered, which will reduce the neutron and proton effective mass, and depress the amplitude of cross section. The effect of three body force is shown to be repulsive, especially in high densities and large momenta, which will suppress the cross section markedly.展开更多
The three-body force effects on the equation of state and its iso-spin dependence of asymmetric nuclear matter and on the proton fraction in neutron star matter have been investigated within Brueckner-Hartree-Fock app...The three-body force effects on the equation of state and its iso-spin dependence of asymmetric nuclear matter and on the proton fraction in neutron star matter have been investigated within Brueckner-Hartree-Fock approach by using a microscopic three-body force. It is shown that, even in the presence of the three-body force, the empirical parabolic law of the energy per nucleon vs. isospin asymmetry is fulfilled in the whole asymmetry range and also up to high density. The three-body force provides a strong enhancement of symmetry energy at high density in agreement with relativistic approaches. It also shows that the three-body force leads to a much more rapid increasing of symmetry energy with density in relatively high density region and to a much lower threshold density for the direct URCA process to occur in a neutron star as compared to the predictions adopting only pure two-body force.展开更多
A real-time animation technique for a kind of non-rigid objects, flexible and thin objects, is proposed, which can update with stability the state of n mass points of the mass-spring (MS) modei with time complexity of...A real-time animation technique for a kind of non-rigid objects, flexible and thin objects, is proposed, which can update with stability the state of n mass points of the mass-spring (MS) modei with time complexity of O (n ). The new implicit numerical integration technique of the authors, which is based on a simple approximation of the linear system, has great advantages over the existing implicit integration methods. Moreover, experiment shows that the new technique is highly efficient in animating a kind of non-rigid objects, and suitable for the draping module of the 3D garment CAD system.展开更多
A dynamic experimental set-up was utilized to measure ibuprofen solubility in supercritical CO2 at the pressure range of 8-13 MPa and the temperatures of 308, 313 and 318 K. Mole fraction values varied from 0.015&#21...A dynamic experimental set-up was utilized to measure ibuprofen solubility in supercritical CO2 at the pressure range of 8-13 MPa and the temperatures of 308, 313 and 318 K. Mole fraction values varied from 0.015×10^-3 to 3.261×10^-3 and correlated by using seven different semi empirical equations of state (Bartle, Modi-fied Bartle, Mendez-Teja, Modified Mendez-Teja, Kumar-Johnson, Sung-shim and Gordillo) as well as seven cubic equations of state (van der Waals, Redlich-Kwong, Soave-Redlich-Kwong, Peng-Robinson, Stryjek-Vera, Patel-Teja-Valderana and Pazuki). Single and twin-parametric van der Walls mixing rules (vdW1, vdW2) were ap-plied in order to estimate the supercritical solution properties. The physicochemical properties were also obtained using Joback, Lydersen and Ambrose methods. Absolute average relatives deviation (AARD) were calculated and compared for all the correlating systems. Results showed that among the cubic equations of state (EOSs) the Pazuki equation (AARD=19.85% using vdW1 and AARD=8.79% using vdW2) and SRK equation (AARD=19.20%using vdW1 and AARD=10.03%using vdW2) predicted the ibuprofen solubility in supercritical CO2 with the least error in comparison to the others. Among the semi-empirical EOSs the most desirable deviation (AARD〈10%) was obtained by using Modified Bartle and Modified Mendez-Teja equations in all the studied temperatures.展开更多
基金supported by the Asia-Link project(CN/ASIA-LINK/008(94791))of the European Commissionin part by National Natural Science Foundation of China under Grant Nos.10775061,10505016,10575119,and 10175074+1 种基金the Knowledge Innovative Project of CAS under Grant No.KJCX3-SYW-N2the Major Prophase Research Project of Fundamental Research of the Ministry of Science and Technology of China under Grant No.2007CB815004
文摘We provide a microscopic calculation of neutron-proton and proton-proton cross sections in symmetric nuclear matter at various densities, using the Brueckner Hartree-Fock approximation scheme with the Argonne Va4 potential including the contribution of microscopic three-body force. We investigate separately the effects of three-body force on the effective mass and on the scattering amplitude. In the present calculation, the rearrangement contribution of three-body force is considered, which will reduce the neutron and proton effective mass, and depress the amplitude of cross section. The effect of three body force is shown to be repulsive, especially in high densities and large momenta, which will suppress the cross section markedly.
文摘The three-body force effects on the equation of state and its iso-spin dependence of asymmetric nuclear matter and on the proton fraction in neutron star matter have been investigated within Brueckner-Hartree-Fock approach by using a microscopic three-body force. It is shown that, even in the presence of the three-body force, the empirical parabolic law of the energy per nucleon vs. isospin asymmetry is fulfilled in the whole asymmetry range and also up to high density. The three-body force provides a strong enhancement of symmetry energy at high density in agreement with relativistic approaches. It also shows that the three-body force leads to a much more rapid increasing of symmetry energy with density in relatively high density region and to a much lower threshold density for the direct URCA process to occur in a neutron star as compared to the predictions adopting only pure two-body force.
文摘A real-time animation technique for a kind of non-rigid objects, flexible and thin objects, is proposed, which can update with stability the state of n mass points of the mass-spring (MS) modei with time complexity of O (n ). The new implicit numerical integration technique of the authors, which is based on a simple approximation of the linear system, has great advantages over the existing implicit integration methods. Moreover, experiment shows that the new technique is highly efficient in animating a kind of non-rigid objects, and suitable for the draping module of the 3D garment CAD system.
文摘A dynamic experimental set-up was utilized to measure ibuprofen solubility in supercritical CO2 at the pressure range of 8-13 MPa and the temperatures of 308, 313 and 318 K. Mole fraction values varied from 0.015×10^-3 to 3.261×10^-3 and correlated by using seven different semi empirical equations of state (Bartle, Modi-fied Bartle, Mendez-Teja, Modified Mendez-Teja, Kumar-Johnson, Sung-shim and Gordillo) as well as seven cubic equations of state (van der Waals, Redlich-Kwong, Soave-Redlich-Kwong, Peng-Robinson, Stryjek-Vera, Patel-Teja-Valderana and Pazuki). Single and twin-parametric van der Walls mixing rules (vdW1, vdW2) were ap-plied in order to estimate the supercritical solution properties. The physicochemical properties were also obtained using Joback, Lydersen and Ambrose methods. Absolute average relatives deviation (AARD) were calculated and compared for all the correlating systems. Results showed that among the cubic equations of state (EOSs) the Pazuki equation (AARD=19.85% using vdW1 and AARD=8.79% using vdW2) and SRK equation (AARD=19.20%using vdW1 and AARD=10.03%using vdW2) predicted the ibuprofen solubility in supercritical CO2 with the least error in comparison to the others. Among the semi-empirical EOSs the most desirable deviation (AARD〈10%) was obtained by using Modified Bartle and Modified Mendez-Teja equations in all the studied temperatures.