[en] A key technology of γ-EMP assorted simulator is the synchronous operating between the γ-simulator and the EMP-simulator. The author analyzes the requirement of the assorted simulator to the synchronous capability of γ-simulator and points out that the time jitter ΔT_γ in γ-simulator should reach to the level less than half width at half maximum of γ-pulse. Then, the difficulties and the methods of improving synchronous capability of Flash-I γ-simulator are analyzed and researched. The synchronous capability and feasibility of Flash-1-A as the γ-simulator in the γ-EMP simulator system are discussed also

[en] The prepulse voltage of the Flash-I and its reduction are analysed. The prepulse voltage between the cathode and the anode has been measured with the capacitive voltage detector, and a new improved equivalent circuit model is proposed. The important effect of direct capacity coupling between the intermediate cylinder and the end of diode is pointed out. The prepulse voltage simulated with this model comes closer to the measured result. The scheme of reducing prepulse voltage further is designed

[en] Focus mechanism and influential factors on the cone cylinder focusing of IREB are discussed. In conventional radiant operation of the Flash-1, 'atmospheric shallow cone cylinder' focus set is used, coarse annular beam of average diameter 16 cm and width 3 cm is compressed to approximately solid beam of diameter 9 cm. Through radiant target, the irradiation rate on the window center has increased from 3.87 x 10⁷ C/(kg·s) (1.5 x 10¹¹ R/s) to 1.29 x 10⁸ C/(kg·s) (5 x 10¹¹ R/s). Radiant simulation environment of the high dose rate is provided to examine hardened components and to demarcate nuclear probes

[en] Three different processing technologies are described for the fabrication of SiC/C functionally graded material (FGM), B₄C/Cu coating FGM and W/Cu FGM. The microstructure and physical properties of the FGMs are evaluated. Some plasma-relevant performances of these three FGMs show their prospect as plasma-facing materials in fusion reactors

[en] Sialon as one of the important structural ceramics is being paid more and more attention due to its unique chemistry, crystal structure and microstructure features. α-Sialon has superior hardness, β-sialon possesses high strength and toughness, and (α+β)-sialon is combination of α-sialon and β-sialon. This paper presents the crystal structure, fabrication and properties of α-sialon, β-sialon and (α+β)-sialon. On the basis of their properties, symmetrically compositional functionally graded material (SCFGM) with the advantage of both α-sialon and β-sialon, has been fabricated, its thermal stress has been calculated with finite element analysis method, and its microstructure has been investigated. (author)

[en] Highlights: • ZnO linear resistors have been studied comprehensively with different contents of La₂O₃. Structural and morphological characteristics of the samples were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. The property of resistivity-frequency reveals that the samples could be applied in high-frequency electric field. The dielectric property indicates Maxwell-Wagner interfacial polarization exists in the matrixes. • La³⁺ can be used as donor doping, to reduce the height of barrier at the grain boundary, further improving linear properties. When the doping amount of La₂O₃ is 1 wt%, The resistance temperature coefficient is -6.63×10^-3/°C, the minimum values of the barrier height and the nonlinear coefficient are 0.0787 eV and 1.09, respectively. -- Abstract: ZnO linear resistors have anticipated application prospect in electrical and electronic industry, but the study of La₂O₃ doping is still poor. In this paper, the ZnO linear resistors doped with Al₂O₃, MgO, SiO₂ and La₂O₃ were prepared by the conventional solid-state sintering method, and the effects of La₂O₃ doping on the microstructure and comprehensive electrical properties were studied. Structural and morphological characteristics of the samples were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. The property of resistivity-frequency reveals that the samples could be applied in high-frequency electric field. The dielectric property indicates Maxwell-Wagner interfacial polarization exists in the matrixes. With La₂O₃ content of 1 wt%, ZnO linear resistors have the best linear performance: the grain size is relatively uniform, the resistance temperature coefficient α_T is − 6.63 × 10⁻³/°C, and the nonlinear coefficient α is 1.09. The comprehensive analysis of the influence of La₂O₃ doping on the electrical properties is of important significance for preparing ZnO linear resistors with excellent electrical properties.

[en] The paper has established an equivalent-circuit model of the four-level-coaxial-circular-cone-like magnetically insulated transmission line of PBFA Z by treating its vacuum section as several pieces of lumped inductance in terms of its magnetic insulation properties. The model has incorporated magnetic insulation theory, space-charge-limited flow theory, Mendel's MITL pressure balance equation, and wire-array implosion dynamic model as well as several critical geometric parameters of the MITL. The comparison of calculated results of a typical PBFA Z test by the model with those by other models and measured results indicates that the model be valid and can be used as a convenient tool to design and estimate similar MITL configurations

[en] The effects of modulations applied to the side air rods of two-dimensional (2D) photonic crystal (PC) microcavities on the quality factor Q and the transmission T have been numerically investigated using the multiple-scattering approach for transverse magnetic modes. The investigated 2D PC microcavity with hexagonal lattice is composed of an array of n x n air rods in Si substrates with three air rods removed from the centre, where n is the number of air rods located at the X- and Y-axes. The modulations are attempted by decreasing the size, displacing the position and both decreasing the size and shifting the positions of the side air rods, respectively. From the work, the simulation results show that the Q can be increased by the modulation by changing the field distribution, while T changes vastly. For all microcavities investigated in this work, as a result of the modulations, both Q and T are strongly correlated with the modulations and T will always decrease with the increase in Q.

[en] Fluorine-doped VO₂(M) nanoparticles have been successfully synthesized using the hydrothermal method at a supercritical temperature of 490 °C. The pristine VO₂(M) has the critical phase transformation temperature of 64 °C. The morphology and homogeneity of the monoclinic structure VO₂(M) were adopted by the fluorine-doped system. The obtained particle size of the samples is smaller at the higher concentration of anion doping. The best reduction of critical temperature was achieved by fluorine doping of 0.13% up to 48 °C. The thin films of the fluorine-doped VO₂(M) showed pronounced thermochromic property and therefore are suitable for smart window applications. (paper)

[en] Highlights: ► First principles calculation were carried out for Mo, N, and (Mo, N) co-doped TiO₂. ► The geometrical, electronic and optical properties of the doped models were evaluated. ► Mo and N co-doping introduce Mo 4d and N 2p states in the band gap. ► (Mo, N) co-doped TiO₂ have best electronic and optical properties among all models. - Abstract: Density functional theory calculations were performed in order to investigate the effect of (Mo, N) co-doping on the electronic and optical properties of anatase TiO₂. Comparative theoretical study is organized using different doping models including single Mo doping, single N doping in anatase TiO₂ and three different models of (Mo, N) co-doped TiO₂ regarding the position of the dopants with respect to each other. Mo doping in anatase TiO₂ reduced the band gap of pure TiO₂ from 2.12 eV to 1.90 eV by introducing Mo 4d state below the conduction band and shifted the Fermi level from the top of the valence band to the bottom of the conduction band which verifies the n-type doping nature of Mo in TiO₂. Isolated N 2p state was created above the top of the valence band due to the N doping and the band gap of N–TiO₂ was effectively reduced to about 0.78 eV; however the unoccupied N 2p states annihilate the electron–hole pairs which will limit the efficiency of N–TiO₂ in visible light photocatalytic activity. (Mo, N) co-doped TiO₂ has narrowed band gap of about 1.50 eV and simultaneous impurity states, one is above the top of the valence band (N 2p) and the other is just below the conduction band (Mo 4d). The introduction of Mo 4d state changes the character of N 2p states from unoccupied to occupied states which will lead to removal of the electron–hole recombination center and enhance the visible light photocatalytic activity. Furthermore, optical absorption coefficient spectra results show that (Mo, N) co-doping in anatase TiO₂ can have enhanced optical absorption in the visible region compared with that of N–TiO₂ and Mo–TiO₂, which is attributed to the reduced recombination centers. It is argued that (Mo, N) co-doped TiO₂ shows enhanced visible light photocatalytic activity due to the effective utilization of electron–hole pairs in the oxidation/reduction process.