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In order to improve and solve the capability of small and medium enterprises to design new products, the principle of operation of the three-lobe Roots blower rotor was firstly analyzed, and the characteristics of meshing of the rotor profile were analyzed. The meshing design formula was given. Based on this, the 3L41WD involute Roots blower design was taken as an example to calculate its full line type and to analyze and determine the meshing tolerance. Finally, the field test proved the rationality of the design, and provided guidance for SMEs to rapidly design the involute Roots blower rotor.

The validity of single-fluid model in inertial confinement fusion simulations is studied by comparing the results of the multi- and single-fluid models. The multi-fluid model includes the effects of collision and interpenetration between fluid species. By simulating the collision of fluid species, steady-state shock propagation into the thin DT gas and expansion of hohlraum Au wall heated by lasers, the results show that the validity of single-fluid model is strongly dependent on the ratio of the characteristic length of the simulated system to the particle mean free path. When the characteristic length L is one order larger than the mean free path λ, the single-fluid model's results are found to be in good agreement with the multi-fluid model's simulations, and the modeling of single-fluid remains valid. If the value of L/λ is lower than 10, the interpenetration between fluid species is significant, and the single-fluid simulations show some unphysical results; while the multi-fluid model can describe well the interpenetration and mix phenomena, and give more reasonable results.

Recent years have witnessed intense activity concerning the study of nuclei with equal numbers of neutrons and protons (N = Z). Exotic properties have been exhibited in the N = Z nuclei, especially in those with atomic masses around 80. In the present paper, the projected shell model (PSM) together with a relativistic Hartree–Bogoliubov (RHB) theory is used to study the nuclear structure near the N = Z line in the mass A ≈ 80 region. For three Zr isotopes 80,82,84Zr, the projected potential energy surfaces and ground state bands are calculated. It is shown that shape coexistence occurs in all of these nuclei. Moreover, we find that the residual neutron-proton interaction strongly affects the ground state band of 80Zr; however, it slightly modifies those of 82Zr and 84Zr.

The effects of atomic-level mixing are systemically investigated in a multifluid interpenetration mix model, and results are compared with the single-fluid model's simulations and experimental data. It is shown that increasing the model free parameter α, shock Mach number, and the initial density discontinuity makes the mix length and fraction of mixing particle increase, resulting in the lower shock temperatures compared with the results of single-fluid model without mixing. Recent high-compressibility direct-drive spherical implosions on OMEGA are simulated by the interpenetration mix model. The calculations with atomic mixing between fuel and shell match quite well with the observations. Without considering any mixing, the calculated neutron yields and ion temperatures are overpredicted; while inclusion of the interpenetration mix model with the adjustable parameter α could fit the simulated neutron yields and ion temperatures well with experimental data.

The control and handling of fluids is central to many applications of the lab-on-chip. This paper analyzes the basic theory of manipulating different electrolytes and finds the two-dimensional model. Coulomb force and dielectric force belonging to the body force of different electrolytes in the microchannel were analyzed. The force criterion at the interface was concluded, and testified by the specific example. Three basic equations were analyzed and applied to simulate the phenomenon. The force criterion was proved to be correct based on the simulation results.

Deconfinement phase transition and neutrino trapping in (proto)neutron star matter are investigated in a chiral hadronic model (also referred to as the FST model) for the hadronic phase (HP) and in the color-flavor-locked (CFL) quark model for the deconfined quark phase. We include a perturbative QCD correction parameter αs in the CFL quark matter equation of states. It is shown that the CFL quark core with K0 condensation forms in neutron star matter with the large value of αs. If the small value of αs is taken, hyperons suppress the CFL quark phase and the HP is dominant in the high-density region of (proto)neutron star matter. Neutrino trapping makes the fraction of the CFL quark matter decrease compared with those without neutrino trapping. Moreover, increasing the QCD correction parameter αs or decreasing the bag constant B and the strange quark mass ms can make the fraction of the CFL quark matter increase, simultaneously, the fraction of neutrino in protoneutron star matter increases, too. The maximum masses and the corresponding radii of (proto)neutron stars are not sensitive to the QCD correction parameter αs.

The total energy loss of N+q ions (for v < Bohr velocity) grazing on the Al(111) has been simulated without any 'fit' parameter and compared with the experimental data. The energy loss due to the charge exchange, happening before the N+q hits the Al(111) surface, is studied. The present simulation shows that the energy loss strongly depends on the charge state of the projectile and the lattice orientation of Al(111) surface. The calculated total energy loss agrees with experimental data very well.

The collective Hamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree–Bogoliubov (TDHB) theory. The validity of the collective Hamiltonian is checked in the two special cases of the multi-O(4) model: the case where the number of the shells is equal to one (a single j-shell case), and the case where the Hartree–Bogoliubov equilibrium point is spherical (the spherical case). The collective Hamiltonian constitutes a good starting point to study nuclear shape coexistence.

Based on the Dyson–Schwinger approach, a method for obtaining the small current quark mass effect on the dressed gluon and quark propagator is developed. A comparison with the results of the previous approach is given.

Based on the Dyson–Schwinger approach, we propose a new method for calculating vacuum susceptibilities. As an example, the vector vacuum susceptibility is calculated. A comparison with the results of the previous approaches is presented.

In this letter, we report a novel phenomenon of photoisomerization-induced changes in liquid crystalline azobenzene polymers P12 Langmuir-Blodgette monolayer deposited on gold film by irradiating the monolayer with UV (360 nm) and blue (450 nm) lights, which was investigated by surface plasmon resonance technique. It has been shown that it is possible to switch the refractive indices reversibly by irradiating these films with light of appropriate wavelength.

The energy term corresponding to the first order of the strain in Taylor series expansion of the energy with respect to strain is always ignored when high-pressure elastic constants are calculated. Whether the modus operandi would affect the results of the high-pressure elastic constants is still unsolved. To clarify this query, we calculate the high-pressure elastic constants of tantalum and rhenium when the energy term mentioned above is considered and neglected, respectively. Results show that the neglect of the energy term corresponding to the first order of the strain indeed would influence the veracity of the high-pressure elastic constants, and this influence becomes larger with pressure increasing. Therefore, the energy term corresponding to the first-order of the strain should be considered when the high-pressure elastic constants are calculated.

The single-electron capture cross sections for the impact of rare-earth ions Ce+, Ho+ on H2 are measured in the energy range 3-8 keV by `growth rate' method. The measurement also reveals that the incident ions are predominantly in ground state.

In this study, we illustrate the effective medium theories in the designs of three-dimensional composite metamaterials of both negative permittivity and negative permeability. The proposed metamaterial consists of random coated spheres with sizes smaller compared to the wavelength embedded in a dielectric host. Simple design rules and formulas following the effective medium models are numerically and analytically presented. We demonstrate that the revised Maxwell—Garnett effective medium theory enables us to design three-dimensional composite metamaterials through the assembly of coated spheres which are random and much smaller than the wavelength of the light. The proposed approach allows for the precise control of the permittivity and the permeability and guides a facile, flexible, and versatile way for the fabrication of composite metamaterials.

In the framework of the Hartree—Fock—Bogoliubov (HFB) approach with Skyrme interactions SLy5+T, SLy5+Tw and several sets of TIJ parametrizations, i.e. the Skyrme interaction parametrizations including the tensor terms, the proton density distribution in 34Si and 46Ar nuclei is calculated with and without the tensor force. It is shown that the bubble effect in 34Si does not depend a great deal on the Skyrme parametrization and the proton density distribution in 34Si is hardly influenced by the tensor force. As to 46Ar, the SLy5+Tw parametrization favors the formation of the bubble structure due to the inversion between the 2s1/2 and 1d3/2 orbits (2s1/2−1d3/2 inversion). The inversion mechanism induced by the SLy5+Tw interaction is analyzed based on the proton single-particle spectra obtained from the SLy5 and SLy5+Tw interactions as well as the wave functions of the 2s1/2 and 1d3/2 states.

CoxZn1−x nanorod arrays were fabricated by electrodeposition in porous anodic aluminum oxide templates at different electric potentials. X-ray diffraction and transmission electron microscopy indicate that highly-ordered and uniform nanorods have been fabricated. The amounts of Co and Zn contents are investigated using energy dispersive spectroscopy, which demonstrates that the atom ratio of the alloy nanorods changes with the deposition potential. In addition, magnetic measurements show that the magnetic isotropy Co-rich CoZn nanorods will change to magnetic anisotropy nanorods with the easy axis parallel to the rod long axis with decreasing Co content.

National Natural Science Foundation of China [10605018, 10975116, 10675170]; Program for New Century Excellent Talents in University [NCET-07-0730]; National Basic Research Program of Chin [2007CB815003]

The yrast bands of the even-even dysprosium isotopes 164–174Dy are calculated up to high angular momentum 34ħ based on the projected shell model. Our calculations are in good agreement with the experiments quantitatively. They predict that an energy minimum of the first 2+ state in these isotopes exists around the neutron mid-shell N = 104, implying the maximum collectivity in 66170Dy104, however, the energy ratio R4 = E(4+1)/E(2+1) reaches a saturation at N = 102. Meanwhile, the back-bending plots of these yrast bands are examined carefully. It is found that the sharpness of the back-bending has a gradual shift along the dysprosium isotopic chain, namely, the slope of the back-bending becomes steeper as the neutron number increases except for an irregularity of a decreasing dip angle in the double mid-shell nucleus 170Dy. We suggest that 170Dy undergoes a dual alignment with midshell high-j protons and neutrons aligning simultaneously at spin I ≈ 16ħ, which probably results in the distinctive back-bending behavior.