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The macroscopic deformed potential energy for super-heavy elements Z = 120 is determined within a generalized liquid drop model (GLDM). The shell correction is calculated with the Strutinsky method and the microscopic single particle energies are derived from the shell model in an axially deformed Woods–Saxon potential with the same quasi-molecular shape. The total potential energy of a nucleus is calculated by the macro-microscopic method as the summation of the liquid-drop energy and the Strutinsky shell correction. The theory is adopted to describe the deformed potential energies in a set of cold reactions. The neck in the quasi-molecular shape is responsible to the deep valley of the fusion barrier due to shell corrections. In the cold fusion path, the double-hump fusion barrier is predicted by the shell correction and complete fusion events may occur. The results show that some of projectile–target combinations in the entrance channel, such as 50Ca+252Fm→ 302120* and 58Fe+244Pu→ 302120*, favour the fusion reaction, which can be considered as candidates for the synthesis of super heavy nuclei Z = 120 and the former might be the best cold fusion reaction to produce the nucleus 302120 among them.

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Graphene oxide (GO) sheets were synthesized via a modified Hummers method. GO dispersion with a high concentration of 6 mg ml−1 was chosen to form GO hydrogel, followed by chemical reduction to derive a free–standing reduced GO (rGO) film. According to the x-ray diffraction (XRD) analysis, it has a [0 0 1] crystalline orientation in the film thickness direction. The rGO film has a densely stacked laminated structure and highly anisotropic characteristic of electrical conductivities. The light-weight rGO wire also demonstrates its excellent flexible and fire-retardant characteristics. Stress–strain measurements revealed the mechanical properties of the GO film can got further improved after chemical reduction. Electrical transport measurement indicates that rGO film exhibit semiconducting behavior with negative temperature coefficient characteristic. A temperature dependence of the conductivity from 20 to 297 K reveals that the carrier transport mechanism is thermally activated band conduction above 200 K and three-dimensional (3D) Mott's variable range hopping below 100 K. The parameters such as a density of the localized electron states and a localization length of the wave function have been determined from the plot of conductivity versus (versus) temperature.

The strange hadronic matter with nucleons, h-hyperons and Xi -hyperons is studied by using an effective nuclear model in a mean-field approximation. The density and strangeness fraction dependence of the effective baryon masses as well as the saturation properties and stabilities of the strange hadronic matter are discussed.

The effects of the tensor coupling term on nuclear matter in the Zimanyi-Moszkowki (ZM) model are investigated. It is shown that the tensor coupling term in the ZM model leaves the thermodynamical properties of nuclear matter almost unchanged. The corrections of tensor coupling to the critical point of the liquid-gas phase transition are given.

Within the framework of Brueckner-Hartree-Fock method, the in-medium nucleon-nucleon (NN) cross section is calculated. We base our investigation on a separable Paris potential for the NN interaction and a continuous choice for the single particle spectrum. It is found that the in-medium cross section is strongly modified by medium effect. In particular, with increasing of nuclear density, the cross sections decrease. This indicates a proper treatment of the density dependence of the in-medium NN cross sections is important.

The optimal harvesting problem of a stochastic time delay logistic model with Levy jumps is considered in this article. We first show that the model has a unique global positive solution and discuss the uniform boundedness of its pth moment with harvesting. Then we prove that the system is globally attractive and asymptotically stable in distribution under our assumptions. Furthermore, we obtain the existence of the optimal harvesting effort by the ergodic method, and then we give the explicit expression of the optimal harvesting policy and maximum yield.

The strange hadronic matter with nucleon, Λ-hyperon and Ξ-hyperon is studied by using a chiral symmetry model in a mean-field approximation. The saturation properties and stabilities of the strange hadronic matter are discussed. The result indicates a quite large strangeness fraction (fS) region where the strange hadronic matter is stable against particle emission. In the large fS region, the Ξ component dominates, resulting in a deep minimum in the curve of the binding energy per baryon EB versus the strangeness fraction fS with (EB, fS) (-26.0 MeV, 1.23).

One-pion exchange correction to the conventional two-nucleon mechanism in the nuclear neutrinoless double beta decay is discussed. A numerical calculation is carried out for decay. The results indicate that this correction is absolutely negligible, compared with the conventional two-nucleon mechanism.

The finite temperature real time Green function method with normal pair cut off (NPC) approximation is applied to deriving the equation of state for finite and asymmetric nuclear matter with the Gogny effective interaction. The dependences of the critical temperature for liquid-gas phase transition on nucleon number, asymmetry and Coulomb potential are discussed.

Effects of spike frequency adaptation (SFA) on the synchronous behavior of population neurons are investigated in electrically coupled networks with a scale-free property. By a computational approach, we corroborate that pairwise correlations between neurons would decrease if neurons exhibit the feature of SFA, which is similar to previous experimental observations. However, unlike the case of pairwise correlations, population activities of neurons show a rather complex variation mode: compared with those of non-adapted neurons, neurons in the networks having weak-degrees of SFA will impair population synchronizations; while neurons exhibiting strong-degrees of SFA will enhance population synchronizations. Moreover, a variation of coupling strength between neurons will not alter this phenomenon significantly, unless the coupling strength is too weak. Our results suggest that synchronous activity of electrically coupled population neurons is adaptation-dependent, and this adaptive feature may imply some coding strategies of neuronal populations.

We design and experimentally demonstrate a broadband metamaterial absorber in the terahertz (THz) band based on a periodic array of aluminum (Al) squares with two different sizes. A thin silicon dioxide (SiO2) film rather than a conventional polyimide (PI) layer is used as a dielectric spacer to separate Al squares from the platinum (Pt) ground plane in our design, which significantly improves the design precision and the feasibility of the device fabrication. The combination of different sizes of Al squares gives rise to an absorption bandwidth of over 210 GHz with an absorption of over 90%. Our results also show that our device is almost polarization-insensitive. It works very well for all azimuthal angles with an absorption of beyond 80%.

The capability of a biological neuron to discriminate the intensity of external stimulus is measured in its dynamic range. In previous studies, a few factors have been reported to be able to enhance the dynamic range, e.g., electrical coupling and active dendrites. Here we numerically show that intrinsic channel noise within neurons has a subtle effect in neuronal dynamic range modulation. Our simulation results indicate that for relatively weak noise intensity, the dynamic range of the neuron is enhanced significantly. However, as the noise intensity becomes stronger, the dynamic range of the neuron is weakened. Further investigation suggests that sodium channel noise and potassium channel noise play opposite roles in modulating the dynamic range. Consequently, the model results suggest a new function of channel noise, that is, a proper value of noise intensity could optimize the dynamic range of neurons.

Tungsten oxide (WO3) thin films have shown interesting properties as lithography resist materials. In this study, the scanning tunneling microscope (STM) was used in air for nanometer etching of α-WO3-x thin films, an n-type semiconductor. The current–voltage (I–V) curve was found to be affected by the water layer absorbed on the surface. For low voltage (< 3 V) with long duration (∼ 10 s) or high voltage pulse (> 3 V) with short pulsewidth (∼ 200 ms), holes were formed on the film surface at high humidity (> 70%) by applying a pulse voltage. A threshold voltage existed for hole formation. Higher pulse voltage and negative polarity corresponded to larger modified size. All the structures formed in STM images were topographical in nature by comparison with the AFM images. The hole formation was reasonably attributed to electrochemistry and high dissolution of WO3 in high pH solutions, which was co-manifested by links between the holes and eroded materials on the surface. Alkaline solutions instead of deionized water were chosen to act in the tip-surface gap. Alkaline ions being expelled from the tip due to electric polarity demonstrated the ion movement and their effect on etching. Lines of nanometer width were fabricated.

The growth dynamics of WO3 thin films by laser ablation of a WO3 monoclinic phase target was studied. Space and time-resolved optical spectra indicated the presence of neutral (WI), ionized (WII) and electronically excited molecule (WO) species in the plume. The reaction between W and O2 was manifested in the laser deposition. Raman spectra showed the films deposited over a target-substrate distance longer than 5 cm or (/and) under an ambient oxygen pressure lower than 200 mTorr deviated from the monoclinic phase of the target with shortened and bent bonds. This was due to the insufficient surface or (/and) gas oxidation. The oxygen pressure and the target-substrate distance were found to be important features in the stoichiometric and monoclinic phase formation. Both gas and surface reactions were responsible for the ultimate monoclinic phase formation in the pulse laser deposition. Parameters were optimised for the oxygen pressure and target-substrate distance.

Scanning tunnelling microscope (STM) modifications on α-WO3-x thin films were carried out in air. Holes and bumps were produced. Two mechanisms were clarified with respect to the water layer attached more or less in modifications. By applying voltage pulses, the high humidity (>60%) raised the probability of hole formations. Connection lines were formed between the holes, confirming a dominant electrochemical nature. The low humidity (

The effect of irradiating amorphous WO3-x thin films by an excimer laser and a Nd-YAG (yttrium-aluminum-garnet) laser on the evolution of electronic states was investigated by scanning tunneling spectroscopy (STS) and X-ray photoelectron spectroscopy (XPS). The original films prepared by pulsed-laser deposition (PLD) were first irradiated by a KrF excimer laser at 248 nm in air. The surface was reduced to a quasi-metallic one with oxygen deficiency and the number of W 5d occupied states was increased. A number of surface states appeared on the films. When the films were subsequently irradiated by the Nd-YAG laser at 1.06 µm in air, the number of W 5d occupied states was reduced due to oxygen restoration. The number of surface states was also greatly reduced. A water layer on the surface, which played a key role in photolysis, was monitored by STS by trapping charges in the Schottky barrier. Atomic force microscopy (AFM) and scanning tunneling microscopy (STM) images of the films at three states: original, surface reduced, and surface restored, were compared in terms of average profile roughness and height. Thermal effects (thermochromism) dominated in the Nd-YAG laser irradiation, resulting in a maximum average roughness in the AFM images, whereas photon effects (photochromism) dominated in excimer laser irradiation, which led to the highest conductance. Slight nanocrystallization occurred in the laser-irradiated films.

The effect of orientation and composition on electrically induced strain and relative permittivity of 600-nm-thick Pb(Zr x Ti1-x )O3 (PZT) films was investigated. High permittivity was obtained near the morphotropic phase boundary (MPB) composition, unaffected by orientation. For films with mixed textures of [111] and [100], the electrically induced strain was maximum near the MPB composition. While the electrically induced strain showed a tendency to increase with increasing Zr concentration x in the films with [111] preferred orientation, for the Pb(Zr0.65Ti0.35)O3 film with [111] preferred orientation, an electrically induced strain of 0.54% was obtained under an electric field of 250 kV/cm.

The 800-nm-thick 0.9 Pb(Zr,Ti)O3–0.1 Pb(Mg,Nb)O3 (PZT–PMN) were prepared by metalorganic deposition (MOD) process on Ti/Pt/Ti bottom electrodes. The structure of the films was investigated by scanning electron microscopy and X-ray diffraction. The piezoelectric properties of the films were characterized by measuring the electrically induced strain using the cantilever method to determine the piezoelectric charge constant (d 31) and by measuring the mechanically induced voltage. The films retain the tetragonal perovskite structure with both [100] and [111] preferred orientations and are made up of columnar grains whose size ranges from 100 nm to 200 nm. The plot of strain versus electrical field shows a hysteresis loop, which reveals that the strain depends on the polarity of the top electrode. The unpoled film is virginally polarized toward the bottom electrode. As a result, d 31 at an electrical field of 170 kV/cm is 190 pC/N for positive polarity and 166 pC/N for negative polarity.