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The nanocrystalline-forming element Cu and magnetic element Co are commonly used as additive elements to tune the structure and improve properties of alloys. In this study, four kinds of amorphous alloys, Fe72Nb12B16, Fe72Nb12B15Cu1, Fe36Co36Nb12B16, and Fe36Co36Nb12B15Cu1, were prepared by melt-spinning and annealed at various temperatures to investigate the effects of Cu and Co additions, individually and in combination, on the crystallization and magnetic properties of Fe72Nb12B16 alloy. The four kinds of alloys exhibited different crystallization behaviors with different primary crystallization phases observed. For the Fe72Nb12B16alloy, only the α-Mn-type metastable phase formed after annealing. The addition of 1 at.% Cu and 36 at.% Co led to the observation of the α-Mn-type and β-Mn-type metastable phases, respectively, and a reduction in the crystallization volume fraction in the metastable phase. The Fe36Co36Nb12B15Cu1alloy only exhibited α-Fe(Co) phase as a primary phase, and the addition of both Cu and Co completely inhibited the precipitation of the metastable phase. Cu clusters were found in energy dispersive spectroscopy elemental maps. Compared with other alloys, Fe36Co36Nb12B15Cu1 alloy with both Cu and Co exhibited a lower coercivity (Hc) below 973 K.

Both Nb and Mo additions play a vital role in FeCo-based alloys and it is crucial to understand their roles and contents on thermal behavior, microstructural feature and magnetic property of alloys. Nanocrystalline alloy ribbons Fe40Co40Zr9 – y M y B10Ge1 (y = 0–4; M = Nb, Mo) were prepared by crystallizing the as-quenched amorphous alloys. The effects of Nb and Mo additions on structures and properties of the Fe40Co40Zr9B10Ge1 alloy are investigated systemically and compared. With increasing Nb or Mo content, the primary crystallization temperature, grain size of α-Fe(Co) phase and coercivity H c all decrease. Moreover, the effect of Mo addition on thermal behavior, microstructure and magnetic properties of the FeCoZrBGe alloy is greater compared to Nb addition. The gap between primary and secondary crystallization peaks of Mo-containing alloys is wider than that of Nb-containing alloys. Both grain size and H c of Mo-containing alloys are smaller than those of Nb-containing alloys. For Fe40Co40Zr9B10Ge1 alloy, high Mo addition proportion is better compared to high Nb addition proportion.

Many complex networks in real life are embedded in space and most infrastructure networks are interdependent, such as the power system and the transport network. In this paper, we construct two cascading failure models on the multilayer spatial network. In our research, the distancelbetween nodes within the layer obeys the exponential distributionP(l) ∼ exp(–l/ζ), and the lengthrof dependency link between layers is defined according to node position. An entropy approach is applied to analyze the spatial network structure and reflect the difference degree between nodes. Two metrics, namely dynamic network size and dynamic network entropy, are proposed to evaluate the spatial network robustness and stability. During the cascading failure process, the spatial network evolution is analyzed, and the numbers of failure nodes caused by different reasons are also counted, respectively. Besides, we discuss the factors affecting network robustness. Simulations demonstrate that the larger the values of average degree 〈k〉, the stronger the network robustness. As the lengthrdecreases, the network performs better. When the probabilitypis small, asζdecreases, the network robustness becomes more reliable. Whenpis large, the network robustness manifests better performance asζincreases. These results provide insight into enhancing the robustness, maintaining the stability, and adjusting the difference degree between nodes of the embedded spatiality systems.

A plasma is produced in air by using a high-intensity Q-switch Nd:YAG pulsed laser to irradiate a solid target, and the impulses delivering from the plasma to the target are measured at different laser power densities. Analysing the formation process of laser plasma and the laser supported detonation wave (LSDW) and using fluid mechanics theory and Pirri's methods, an approximately theoretical solution of the impulse delivering from the plasma to the target under our experimental condition is found. Furthermore, according to the formation time of plasma and the variation of pressure in plasma in a non-equilibrium state, a physical model of the interaction between the pulse laser and the solid target is developed. The plasma evolutions with time during and after the laser pulse irradiating the target are simulated numerically by using a three-dimensional difference scheme. And the numerical solutions of the impulse delivering from the plasma to the target are obtained. A comparison among the theoretical, numerical and experimental results and their analyses are performed. The experimental results are explained reasonably. The consistency between numerical results and experimental results implies that the numerical calculation model used in this paper can well describe the mechanical action of the laser on the target.

In this paper, the compositions in a laser absorption region can be determined from the experiment of laser impulse coupling. When the ambient pressure varies from 9325 to 33325Pa, the compositions are vapour and plasma; while from 35325 to 101325Pa, they are ambient air and plasma. By analysing the relation between the degree of compression and the ambient pressure, the compositions can be determined and the variation of plasma can be explained.

We perform micromagnetic simulations on the switching of magnetic vortex core by using spin-polarized currents through a three-nanocontact geometry. Our simulation results show that the current combination with an appropriate current flow direction destroys the symmetry of the total effective energy of the system so that the vortex core can be easier to excite, resulting in less critical current density and a faster switching process. Besides its fundamental significance, our findings provide an additional route to incorporating magnetic vortex phenomena into data storage devices.

Based on the skewed function, the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are investigated, where the climate states are referred to as State I, State II and State III, i.e., the daily minimum temperature records of 1961–1990, 1971–2000, and 1981–2009. The results show that in space the frequency of high temperature events in summer decreases clearly in the lower and middle reaches of the Yellow River in State I and that low temperature events decrease in northern China in State II. In the present state, the frequency of high temperature events increases significantly in most areas over China except the north east, while the frequency of low temperature events decreases mainly in north China and the regions between the Yangtze River and the Yellow River. The distributions of frequencies and strengths of extreme temperature events are consistent in space. The analysis of time evolution of extreme events shows that the occurrence of high temperature events become higher with the change in state, while that of low temperature events decreases. High temperature events are becoming stronger as well and deserve to be paid special attention.

Under the condition of two different cases, the absorption of a pulsed probe field and its slow propagation in a triple semiconductor quantum well are investigated. The result shows that semiconductor medium becomes transparent due to the action of control field. Another result shows that by choosing appropriate physical parameters, the slow propagation of the input field can be achieved. The proposed scheme has some potential applications and may lead to the development of the controlled technique of optical buffers and optical delay lines.

In this paper a new continuous variable called core-ratio is deflned to describe the probability for a residue to be in a binding site, thereby replacing the previous binary description of the interface residue using 0 and 1. So we can use the support vector machine regression method to flt the core-ratio value and predict the protein binding sites. We also design a new group of physical and chemical descriptors to characterize the binding sites. The new descriptors are more efiective, with an averaging procedure used. Our test shows that much better prediction results can be obtained by the support vector regression (SVR) method than by the support vector classiflcation method.

This paper numerically investigates the magnetoelastic instability in the S = 1/2 XXZ rings containing finite spins N with antiferromagnetic nearest-neighbour (NN) and next-nearest neighbour (NNN) coupling. It finds that, as the NN anisotropy Δ1 equals the NNN anisotropy Δ2, there exists a critical NNN coupling strength Jc2 (≈ 0.5), at which the systems always locate in dimerized phase for arbitrary large spring constant. As Δ1 ≠ Δ2, the values of Jc2 are dependent on N and the difference of (Δ1 – Δ2).