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Based on both very obvious isospin effect of the neutron–proton number ratio of nucleon emissions (n/p)nucl on symmetry potential and (n/p)nucl's sensitive dependence on symmetry potential in the nuclear reactions induced by halo-neutron projectiles, compared to the same mass stable projectile, probing symmetry potential is investigated within the isospin-dependent quantum molecular dynamics with isospin and momentum-dependent interactions for different symmetry potentials U1sym and U2sym. It is found that the neutron-halo projectile induces very obvious increase of (n/p)nucl and strengthens the dependence of (n/p)nucl on the symmetry potential for all the beam energies and impact parameters, compared to the same mass stable projectile under the same incident channel condition. Therefore (n/p)nucl induced by the neutron-halo projectile is a more favourable probe than the normal neutron-rich and neutron-poor projectiles for extracting the symmetry potential.

We study the average property of the isospin effects of reaction mechanism induced by neutron-halo nuclei within the isospin-dependent quantum molecular dynamics model. We find that the extended neutron density distribution for the neutron-halo projectile brings an important isospin effect into the reaction mechanism, which induces the decrease of nuclear stopping R; however, it induces the obvious increases of the neutron-proton ratio of nucleon emissions (n/p)nucl for all of the beam energies in this work, compared to the same mass stable colliding system.

We investigate the role of isospin momentum-dependent interaction on the isospin fractionation ratio and its dynamical mechanism in the intermediate energy heavy ion collisions, by inserting an isospin degree of freedom into the momentum-dependent interaction to obtain an isospin momentum-dependent interaction given in a form practically usable in the isospin-dependent quantum molecular dynamics model. It is found that the isospin momentum-dependent interaction brings an important isospin effect into the isospin fractionation ratio. In particular, the isospin momentum-dependent interaction reduces obviously the reduction of isospin fractionation ratio. Thus the isospin dependence of momentum-dependent interaction is thus important for studying accurately the equation of state of isospin asymmetry nuclear matter.

We investigate the isospin effect of Coulomb interaction on the momentum dissipation or nuclear stopping in the intermediate energy heavy ion collisions by using the isospin-dependent quantum molecular dynamics model. The calculated results show that the Coulomb interaction induces obviously the reductions of the momentum dissipation. We also find that the variation amplitude of momentum dissipation induced by the Coulomb interaction depends sensitively on the form and strength of symmetry potential. However, the isospin effect of Coulomb interaction on the momentum dissipation is less than that induced by the in-medium nucleon–nucleon cross section. In this case, Coulomb interaction does not change obviously the isospin effect of momentum dissipation induced by the in-medium two-body collision. In particular, the Coulomb interaction is preferable for standing up the isospin effect of in-medium nucleon–nucleon cross section on the momentum dissipation and reducing the isospin effect of symmetry potential on it, which is important for obtaining the feature about the sensitive dependence of momentum dissipation on the in-medium nucleon–nucleon cross section and weakly on the symmetry potential.

Isospin effects of the mean field and two-body collision on the fragmentation as well as their dependences on the momentum-dependent interaction at intermediate energy heavy ion collisions are studied by using an isospin-dependent quantum molecular dynamics model. We find the prominent isospin effects of the multiplicity of the intermediate mass fragments Nimf, where Nimf depends sensitively on the isospin effect of the in-medium nucleon-nucleon cross section and weakly on the variation of symmetry potential in the intermediate energy region. The momentum dependence interaction enhances the sensitivity of Nimf on the isospin effect of two-body collision.

The entrance channel dependence of the isospin effects of nuclear stopping in intermediate energy heavy-ion collisions has been studied by using an isospin-dependent quantum molecular dynamics with three different kinds of symmetry potentials. It is shown that nuclear stopping is sensitive to the beam energy, the impact parameter and the mass of the colliding system, especially very sensitive to the isospin dependence of the in-medium nucleon-nucleon cross section, but insensitive to the symmetry potential and the neutron-to-proton ratio of the colliding system. From this investigation, it is proposed that nuclear stopping can be used as a new probe to extract the information on the isospin dependence of the in-medium nucleon-nucleon cross section in intermediate energy heavy-ion collisions.

The medium effect of nucleon–nucleon cross section σmedNN(αm) on the isoscaling parameter α is investigated for two central nuclear reactions 40Ca+40Ca, 60Ca+60Ca within isospin-dependent quantum molecular dynamics at beam energies from 40 to 50 MeV/nucleon. It is found that there is the very obvious medium effects of nucleon–nucleon cross section σmedNN(αm) on the isoscaling parameters α. In this case the isoscaling parameter α is a possible probe of the medium effect of nucleon–nucleon cross section σmedNN(αm) in the heavy ion collisions. The mechanism of the above-mentioned properties is studied and discussed.

We studied the effect of Coulomb interaction on the isospin fractionation in the intermediate energy heavy ion collisions by using the isospin-dependent quantum molecular dynamics model. The calculated results show that Coulomb interaction induces the reduction of the isospin fractionation process with the evolutions of neutron–proton ratio and mass of system. Because Coulomb interaction is repulsive for the proton, more binding protons become free, which produces the neutron-poor gas phase and neutron-rich liquid phase, compared to the neutron–proton ratio of the system. The isospin fractionation degree is weakened by the Coulomb term. In contrast, the symmetry potential is repulsive for neutrons and attractive for protons in the neutron-rich system, and then the binding neutrons more than the protons become free, which produces a neutron-rich gas phase and neutron-poor liquid phase, so that the isospin fractionation degree is increased. The competition between the effects from the Coulomb interaction and the symmetry potential induces the reduction of the isospin fractionation degree for all the system masses. The properties for the sensitive dependence of isospin fractionation degree on the symmetry potential and weak dependence on the nucleon–nucleon cross section are preserved for all the neutron-rich systems.

In accordance with the recent experimental progress of the controllable spin-spin interactions, the Heisenberg model after an interaction quench is discussed. The Hamiltonian of the system out of equilibrium is introduced and treated by the flow equation method. As a result, the spectrum and zero-point spin deviation are obtained with the help of time-evolved operators. Additionally, other methods are applied to verify the results in mathematics. It is found that the observables show an oscillating behavior. The feasible experimental scheme of the concerned scenario is also mentioned.

ZnO nanorods with different morphologies were fabricated through a simple reaction method. They were characterized by means of powder x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and energy-dispersive x-ray (EDX) spectroscopy. FE-SEM images have shown that the shapes of the ZnO nanorods included straight nanorods, spear-like nanorods with sawtooth-shaped surfaces and lotus root-like nanorods. XRD and EDX indicated that all the nanorods are composed of hexagonal ZnO.

The effect of momentum-dependent interaction on the kinetic energy spectrum of the neutron-proton ratio (n/p)gasb (Ek) for 64Zn + 64Zn is studied. It is found that (n/p)gasb (Ek) sensitively depends on the momentum-dependent interaction and weakly on the in-medium nucleon-nucleon cross section and symmetry potential. Therefore (n/p)gasb(Ek) is a possible probe for extracting information on the momentum-dependent interaction in heavy ion collisions.