[en] Starting from the Vlasov equation in K-space (the Fourier space of velocity v), a new form of gyro-kinetic equation of plasma and its solution are given. In several important cases it is simpler than the old form. (author)

[en] Zirconium is a kind of deuterium absorption material and can be used as a deuterium carrier in the nuclear industry. However, zirconium usually cracks after deuterium absorption and therefore fails in its application. In this paper, the effects of deuterium absorption temperature, deuterium absorption pressure and interrupted cooling on the cracking of deuterium absorption Zircaloy-4 alloys have been investigated. The results show that as the deuterium absorption temperature decreases from 900 °C to 800 °C or 700 °C, the deuterium absorption amounts and their tendency to crack increase. And with the increase of deuterium absorption pressure, the deuteride types change from δ-ZrD_1_._6_6 to ε-ZrD_1_._8, which is believed to be the key factor in the cracking. Furthermore, the interrupted cooling also has a significant effect on the deuterium absorption cracking. Based on the experimental results, an explanation of why Zircaloy-4 alloy cracks after deuterium absorption is proposed. - Highlights: • Decreasing deuterium absorption temperature will increase cracking in Zircaloy-4. • Increasing of deuterium absorption pressure will increase cracking in Zircaloy-4. • Increasing interrupted temperature will increase cracking in Zircaloy-4. • The mechanism on cracking in deuterium absorption Zircaloy-4 is discussed.

[en] The fusion–fission hybrid reactor can produce energy, breed nuclear fuel, and handle the nuclear waste, etc., with the fusion neutron source striking the subcritical blanket. The passive safety system consists of passive residual heat removal system, passive safety injection system and automatic depressurization system was adopted into the fusion–fission hybrid reactor in this paper. Modeling and nodalization of primary loop, partial secondary loop and passive core cooling system for the fusion–fission hybrid reactor using relap5 were conducted and small break LOCA on cold leg was analyzed. The results of key transient parameters indicated that the actuation of passive safety system could mitigate the accidental consequence of the 4-inch cold leg small break LOCA on cold leg in the early time effectively. It is feasible to apply the passive safety system concept to fusion–fission hybrid reactor. The minimum collapsed liquid level had great increase if doubling the volume of CMTs to increase its coolant injection and had no increase if doubling the volume of ACCs

[en] Fe_4_8Mo_1_4Cr_1_5Y_2C_1_5B_6 (at%) thin film metallic glasses (TFMGs) with various thickness (125–745 nm) were deposited on glass and 304 stainless steel (SS) by using single-alloy target magnetron sputtering. X-ray diffraction and transmission electron microscopy verified the fully amorphous structure of the as-deposited films. Results of dry friction and wear tests against Si_3N_4 demonstrated that Fe-based TFMGs had lower friction coefficient and nearly three times higher wear resistance with respective to 304SS. The corrosion properties of the Fe-based TFMGs were evaluated in an artificial sweat solution by various electrochemical analytical techniques, including potentiodynamic, potentiostatic polarization and Mott–Schottky analysis. It was shown that the Fe-based TFMGs exhibited highly stable passivity and pitting resistance, which was significantly higher than that of uncoated 304SS. The good corrosion resistance of Fe-based TFMGs results from the lower defect density and higher thickness of the as-formed passive film as compared to 304SS. The pitting of the Fe-based TFMGs follows three distinct stages, i.e., pitting initiation, metastable pitting and stable pitting, as well as substrate dissolution-induced film rupture due to the adsorption and penetration of chloride ions in the artificial sweat solution. These findings are expected to broaden the application of Fe-based TFMGs as a highly protective film for electronic device applications. - Highlights: • New Fe-based thin film metallic glasses (TFMGs) were prepared by magnetron sputtering. • Fe-based TFMGs with a higher film thickness exhibited better adhesion. • Fe-based TFMGs show superior wear resistance than 304SS substrate. • Fe-based TFMGs show excellent passivity stability and pitting resistance in artificial sweat. • We captured the whole pitting corrosion processes on Fe-based TFMGs.

[en] Laminar coatings comprising a multi-amorphous Fe₄₈Mo₁₄C₁₅Y₂C₁₅B₆ layer and a crystalline NiCrAl layer were prepared by the high-velocity oxygen fuel technique. The structures of the coatings were studied with X-ray diffraction, scanning electron microscopy and cross-sectional transmission electron microscopy, while the various mechanical properties, such as hardness, strength, interfacial toughness, bonding strength and impact resistance, were investigated by micro/nanoindentation, three-point bending and adhesion testing as well as by tup-drop impacting coupled with finite element method simulations. The results show that composite coatings exhibit an almost fully compact structure at interfaces between the amorphous layer and the NiCrAl layer with an attractive combination of high hardness and bonding strength, good interfacial toughness and high impact resistance with respect to the monolithic amorphous coating. The maximum bonding strength and impact resistance obtained in the laminar coatings reached 40 MPa and 21.2 J, respectively, which are respectively a ∼54% and a 10-fold increase over the monolithic coating. The enhancement of the bonding strength results from the formation of the localized metallurgical bonding as well as complete wettability between the NiCrAl layer and the amorphous layer, which is observed by high-temperature contact angle tests. The improvement in the impact resistance of the composite coatings results from hindering crack propagation and mitigation of stress concentration due to the addition of the soft NiCrAl multilayers. The present work may pave a way to the development of durable, tough and highly impact resistant amorphous–matrix composite coatings for applications in severe loading conditions

[en] Current drive is one of the major issue in controlled nuclear fusion research field. For the steady-state operation, a variety of current drive methods are under systematic investigation. Helicity injection current drive is an attractive method. The experiment on Helicity Injected Tokamak (HIT) obtained 150 kA toroidal driven current applying the coaxial helicity injection, which is the most remarkable results. The author reports the results about equilibrium reconstruction in helicity injected current drive experiment. The reconstruction shows that these plasmas have a tokamak q profile, with a hollow toroidal current profile and up to 110 kA of closed field toroidal current in a low-aspect-ratio configuration. Calculation results also indicates that plasma relaxation state is a non-complete relaxation state away from Taylor State

[en] Thick target γγ coincidence techniques are being used to explore the spectroscopy of otherwise hard-to-reach neutron-rich products of deep-inelastic heavy ion reactions. This production method delivers many product nuclei with moderate yields and the data analysis is often formidable, but it can take advantage of the selectivity of modern γ-ray detector arrays. Extensive γγ coincidence measurements were performed at ATLAS using pulsed beams of ⁷⁶Ge, ⁸⁰Se, and ¹³⁶Xe on lead-backed ^122,124Sn targets 10-15% above the Coulomb barrier. Gamma-ray coincidence intensities were used to map out yield distributions with A and Z for even-even product nuclei around the target and around the projectile. The main features of the yield patterns are understandable in terms of N/Z equilibration. The authors have had most success in studying decays of yrast isomers. Thus far, more than thirty new μs isomers in the Z-50 region have been found and characterized; some examples are presented

[en] A novel ferrocene-contained pyrrole, 4-(1H-pyrrol-1-yl) phenyl ferrocenecarboxylate (FcPy) was synthesized by esterification of 4-(1H-pyrrol-1-yl) phenol (PLPY) and ferrocenecarboxylic acid. Then the homopolymer of FcPy (PFcPy), copolymer of FcPy and pyrrole (P(FcPy-co-Py)), polypyrrole (PPy) were prepared by chemical oxidative polymerization. And the structure, morphology, electrochemical properties of prepared polymers were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), cyclic voltammograms (CV) and electrochemical impedance spectra (EIS), respectively. Also, the charge/discharge properties of the prepared polymers were studied by galvanostatic charge–discharge testing. The results demonstrated that the introduction of ferrocene to polypyrrole obviously improved the specific capacity of PPy cathode and gave a well-defined plateau at the potential rang of about 3.5 V. Under our experimental conditions, the discharge capacity of undoped PPy-based electrodes only presented 16.5 mAh g⁻¹ at 20 mA g⁻¹ between 2.5 and 4.2 V, while PFcPy-based electrodes exhibited an initial discharge capacity of up to 43.2 mAh g⁻¹. Specially, the P(FcPy-co-Py)-based electrodes even showed a discharge capacity of 68.1 mAh g⁻¹ and the improved discharge platform, which were ascribed to the resonance doping effect of pendant group, the advanced electrochemical nature of ferrocene moiety and the loose morphology of copolymer

[en] The principle of the minimum energy dissipation rate is applied to toroidal plasmas with a coaxial direct current helicity injection. The relaxed states are analysed based on the analytical solutions of the resulting Euler-Lagrangian equations. Three typical states are found. The relaxed states are close to the Taylor state if the ratio of current density to magnetic field on the boundary is small enough. The states will deviate from the Taylor state when the ratio increases, but when it approaches a critical value the central part of relaxed plasmas may approach a force free state, and above the critical value both current and magnetic field may reverse in the central part

[en] Numerical simulation of the HT-7U tokamak plasma configuration and plasma current is described by solving MHD equations and surface average transport equations using a suitable code. The evolution of plasma parameter via time is shown. The simulation result can play an important role in the design of the HT-7U tokamak and its plasma system