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Potential energy surfaces of even-even superheavy nuclei are evaluated within the macroscopic-microscopic approximation. A very rapidly converging analytical Fourier-type shape parametrization is used to describe nuclear shapes throughout the periodic table, including those of fissioning nuclei. The Lublin Strasbourg Drop and another effective liquid-drop type mass formula are used to determine the macroscopic part of nuclear energy. The Yukawa-folded single-particle potential, the Strutinsky shell-correction method, and the BCS approximation for including pairing correlations are used to obtain microscopic energy corrections. The evaluated nuclear binding energies, fission-barrier heights, and Q-alpha energies show a relatively good agreement with the experimental data. A simple one-dimensional WKB model a la Swiatecki is used to estimate spontaneous fission lifetimes, while alpha-decay probabilities are obtained within a Gamow-type model., 13 pages, 19 figures

Fission properties of the actinide nuclei are deduced from theoretical analysis. We investigate potential energy surfaces and fission barriers and predict the fission fragment mass-yields of actinide isotopes. The results are compared with experimental data where available. The calculations were performed in the macroscopic-microscopic approximation with the Lublin-Strasbourg Drop (LSD) for the macroscopic part and the microscopic energy corrections were evaluated in the Yukawa-folded potential. The Fourier nuclear shape parametrization is used to describe the nuclear shape, including the non-axial degree of freedom. The fission fragment mass-yields of considered nuclei are evaluated within a 3D collective model using the Born-Oppenheimer approximation., Comment: 11 pages, 12 figures, submitted to the Chinese Physics C. arXiv admin note: text overlap with arXiv:2001.08652

Potential energy surfaces and fission barriers of superheavy nuclei are analyzed in the macroscopic-microscopic model. The Lublin-Strasbourg Drop (LSD) is used to obtain the macroscopic part of the energy, whereas the shell and pairing energy corrections are evaluated using the Yukawa-folded potential. A standard flooding technique has been used to determine the barrier heights. It was shown the Fourier shape parametrization containing only three deformation parameters reproduces well the nuclear shapes of nuclei on their way to fission. In addition, the non-axial degree of freedom is taken into account to describe better the form of nuclei around the ground state and in the saddles region. Apart from the symmetric fission valley, a new very asymmetric fission mode is predicted in most superheavy nuclei. The fission fragment mass distributions of considered nuclei are obtained by solving the 3D Langevin equations., Comment: 20 pages, 17 figures

In this review article, we first briefly introduce the transport theory and quantum molecular dynamics model applied in the study of the heavy ion collisions from low to intermediate energies. The developments of improved quantum molecular dynamics model (ImQMD) and ultra-relativistic quantum molecular dynamics model (UrQMD), are reviewed. The reaction mechanism and phenomena related to the fusion, multinucleon transfer, fragmentation, collective flow and particle production are reviewed and discussed within the framework of the two models. The constraints on the isospin asymmetric nuclear equation of state and in-medium nucleon-nucleon cross sections by comparing the heavy ion collision data with transport models calculations in last decades are also discussed, and the uncertainties of these constraints are analyzed as well. Finally, we discuss the future direction of the development of the transport models for improving the understanding of the reaction mechanism, the descriptions of various observables, the constraint on the nuclear equation of state, as well as for the constraint on in-medium nucleon-nucleon cross sections., 64 pages, 55 figures. Review article for Frontiers of Physics

A first-principles pseudopotential plane-wave method based on density functional theory has been used to investigate the thermodynamic stability and electronic characteristics of long-period stacking ordered (LPSO) phases in Mg–Zn–Y alloys. The obtained lattice constants of each LPSO phase considered are in good agreement with the experimentally determined values, with relative errors ranging from 0.21% to 2.0%. The calculated enthalpies of formation show that 14H and 18R phases can co-exist in the Mg–Zn–Y system, and the 18R phase is easier to form than the 14H phase while solidifying. But the 14H phase is more stable than the 18R phase by the calculation results of reaction energy. And the calculated results are in accord with the experiments for the thermodynamic stability of the two phases. The density of states of these phases reveals that the discrepancy in the stability of LPSO phases could be attributed to the variation of bonding electron numbers at low-energy region of Fermi level. In addition, the calculation of the charge density shows that the Zn Y bond exhibits covalent feature in both 14H and 18R phases, and the covalent bonding of the 14H phase is stronger than that of the 18R phase, which means the 14H phase is more stable than the 18R phase.

It is necessary that the grid-connected inverter was set up in wind generation system (WGS), in order to convey energy generated in WGS to the electrical grid. There are many sorts of inverters, but only two sorts of inverters suit wind generation system, which are current-source and voltage-source inverter, and only the latter is being widely used. The configuration, principle, control and characteristic of the two inverters were analyzed. Results have shown that, voltage-source grid-connected inverter has been the core of the commutation control configuration of direct-driven WGS, which is decided by the peculiarity of itself.

A scheme is proposed for detection of the topology in the one-dimensional Affleck-Kennedy-Lieb-Tasaki model, based on ultracold spinor atomic gas in an optical lattice. For this purpose, a global operation O(θ) is introduced with respect to the breaking of spinrotational symmetry. Consequently, the topology can be manifested unambiguously by identifying the special values of θ where the expectation value of the global operator with degenerate ground states is vanishing. Furthermore, experimentally θ can be detected readily by the interference of ultracold atomic gases. This scheme can be implemented readily in experiment since it does not need the addressing of individual atoms or the probing of a boundary.

Transport simulations are very valuable for extracting physics information from heavy-ion-collision experiments. With the emergence of many different transport codes in recent years, it becomes important to estimate their robustness in extracting physics information from experiments. We report on the results of a transport-code-comparison project. Eighteen commonly used transport codes were included in this comparison: nine Boltzmann-Uehling-Uhlenbeck-type codes and nine quantum-molecular-dynamics-type codes. These codes have been asked to simulate Au + Au collisions using the same physics input for mean fields and for in-medium nucleon-nucleon cross sections, as well as the same impact parameter, the similar initialization setup, and other calculational parameters at 100 A and 400 A MeV incident energy. Among the codes we compare one-body observables such as rapidity and transverse flow distributions. We also monitor nonobservables such as the initialization of the internal states of colliding nuclei and their stability, the collision rates, and the Pauli blocking. We find that not completely identical initializations may have contributed partly to different evolutions. Different strategies to determine the collision probabilities and to enforce the Pauli blocking also produce considerably different results. There is a substantial spread in the predictions for the observables, which is much smaller at the higher incident energy. We quantify the uncertainties in the collective flow resulting from the simulation alone as about 30% at 100 A MeV and 13% at 400 A MeV, respectively. We propose further steps within the code comparison project to test the different aspects of transport simulations in a box calculation of infinite nuclear matter. This should, in particular, improve the robustness of transport model predictions at lower incident energies, where abundant amounts of data are available.

The second phase nucleation and precipitation around the edge dislocation are studied using phase-field method. A new free energy function is established. The simulation results are in good agreement with that of theory of dislocation and theory of non-uniform nucleation.

A generalization of the geometric measure of quantum discord is introduced in this article, based on Hellinger distance. Our definition has virtues of computability and independence of local measurement. In addition it also does not suffer from the recently raised critiques about quantum discord. The exact result can be obtained for bipartite pure states with arbitrary levels, which is completely determined by the Schmidt decomposition. For bipartite mixed states the exact result can also be found for a special case. Furthermore the generalization into multipartite case is direct. It is shown that it can be evaluated exactly when the measured state is invariant under permutation or translation. In addition the detection of quantum phase transition is also discussed for Lipkin-Meshkov-Glick and Dicke model., 10 pages, 7 figures. references are updated. appeared in Communication in Theoretical Physics, 65 (2016), 154-164

The nucleon-nucleon interaction is investigated by using the ImQMD model with the three sets of parameters IQ1, IQ2 and IQ3 in which the corresponding incompressibility coefficients of nuclear matter are different. The charge distribution of fragments for various reaction systems are calculated at different incident energies. The parameters strongly affect the charge distribution below the threshold energy of nuclear multifragmentation. The fragment multiplicity spectrum for $^{238}$U+$^{197}$Au at 15 AMeV and the charge distribution for $^{129}$Xe+$^{120}$Sn at 32 and 45 AMeV, and $^{197}$Au+$^{197}$Au at 35 AMeV are reproduced by the ImQMD model with the set of parameter IQ3. It is concluded that charge distribution of the fragments and the fragment multiplicity spectrum are good observables for studying N-N interaction, the Fermi energy region is a sensitive energy region to explore the N-N interaction, and IQ3 is a suitable set of parameters for the ImQMD model., 10pages,6figures

The penetration probability across an arbitrary nucleus-nucleus potential barrier is studied by using transfer matrix approach, including continuous variations of effective mass. The calculated penetration probabilities for reaction ${}^{16}$O+${}^{208}$Pb are closed to those of WKB and modified Numerov calculations based on the Bass potential. With the transfer matrix approach, the influence of the effective mass on the penetration probability are simultaneously investigated. The calculations imply that the effective mass is an important quantity for studying the hindrance of fusion cross sections of some reactions at deep sub-barrier energies. The fusion cross sections of heavy-ion fusion reactions and the resonance phenomena due to double-hump barriers are also studied with this approach.

To generate the cancer stem cells (CSCs) specific protein CD133 polyclonal antibody for the study of the biological characteristics of CSCs in tumor tissues and CSCs screening for the mouse model.The extracellular peptide of the human CD133 was injected into rabbits to generate polyclonal antibody which was used for glioblastoma(GBM) Western blot and immunohistochemistry.The CD133 antiserum we made could detect both overexpressed myc-CD133 and endogenous CD133 efficiently by Western blot. Immunohistochemistry indicated that the CD133 polyclonal antibody can label CSCs in GBM sections.High efficient and specific CD133 antibody was generated successfully and could be used to label CSCs in tumor sections and screen CSCs for the mouse model.

A unified formula which describes the (pseudo)rapidity distributions of charged particles produced in high energy collisions is presented. The calculated results are compared and found to be in agreement with the experimental data of ${e}^{+}{e}^{\ensuremath{-}}$, $p\overline{p}$, and $AA$ collisions at high energies.