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<jats:p>In order to measure controllability of vertical instability in EAST, the calculation of model-based vertical growth rate, called rt-gamma, has been successfully carried out in real time. The numerical computing method is adapted from rigid plasma response model in TokSys, which is a widely-used analysis tool for tokamak devices in Matlab environment, but the code is rewritten by taking advantage of GPU parallel computing capability to accelerate the computation. The calculation of rt-gamma is validated by comparing it with the corresponding result generated by TokSys for totally 3508 cases. It is shown that the average absolute value of relative errors is about 0.85%. In addition, the calculation program of rt-gamma has been successfully applied during 2019 EAST campaign. The comparison with experimental results is discussed in this paper. The real-time calculation tool is well able to calculate model-based vertical growth rate, which is convenient for fast and continuous evaluations of EAST control system stability performances.</jats:p>

<jats:p>The retention and release of deuterium in W–2%Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> composite materials and commercially pure tungsten after they have been implanted by deuterium plasma (flux ∼ 3.71 × 10<jats:sup>21</jats:sup> D/m<jats:sup>2</jats:sup>⋅s, energy ∼ 25 eV, and fluence up to 1.3 × 10<jats:sup>26</jats:sup> D/m<jats:sup>2</jats:sup>) are studied. The results show that the total amount of deuterium released from W–2%Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> is 5.23 × 10<jats:sup>20</jats:sup> D/m<jats:sup>2</jats:sup>(2.5 K/min), about 2.5 times higher than that from the pure tungsten. Thermal desorption spectra (TDS) at different heating rates (2.5 K/min–20 K/min) reveal that both W and W–2%Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> have two main deuterium trapped sites. For the low temperature trap, the deuterium desorption activation energy is 0.85 eV (grain boundary) in W, while for high temperature trap, the desorption activation energy is 1.57 eV (vacancy) in W and 1.73 eV (vacancy) in W–2%Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>.</jats:p>

<jats:p>We report the measurement of total molybdenum ion density for L-mode and H-mode plasmas on EAST using spectral lines observation and calculation based on an impurity transport code. A flat-filed extreme ultraviolet spectrometer with some spatial resolution is used to obtain the radial profiles of molybdenum spectral line emissions. The absolute calibration for the extreme ultraviolet spectrometer is finished by comparing the calculated bremsstrahlung intensity with the readings of CCD detector. Molybdenum ion transport study is performed using the radial ion density profiles and one-dimensional impurity transport code STRAHL. The total molybdenum density profiles are determined from the transport analysis. The molybdenum density during L-mode and H-mode phases are obtained, which are about 3 and 4 orders of magnitude smaller than the electron density, respectively. An inward pinch is found during the H-mode phase that leads to the peaked profile of molybdenum density.</jats:p>

<jats:p>In the extreme conditions of high altitude, low temperature, low pressure, and high speed, the aircraft engine is prone to flameout and difficult to start secondary ignition, which makes reliable ignition of combustion chamber at high altitude become a worldwide problem. To solve this problem, a kind of multichannel plasma igniter with round cavity is proposed in this paper, the three-channel and five-channel igniters are compared with the traditional ones. The discharge energy of the three igniters was compared based on the electric energy test and the thermal energy test, and ignition experiments was conducted in the simulated high-altitude environment of the component combustion chamber. The results show that the recessed multichannel plasma igniter has higher discharge energy than the conventional spark igniter, which can increase the conversion efficiency of electric energy from 26% to 43%, and the conversion efficiency of thermal energy from 25% to 73%. The recessed multichannel plasma igniter can achieve greater spark penetration depth and excitation area, which both increase with the increase of height. At the same height, the inlet flow helps to increase the penetration depth of the spark. The recessed multichannel plasma igniter can widen the lean ignition boundary, and the maximum enrichment percentage of lean ignition boundary can reach 31%.</jats:p>

<jats:p>The interaction between the supersonic molecular beam (SMB) and the low-temperature plasma is a critical issue for the diagnosis and fueling in the Tokamak device. In this work, the interaction process between the argon SMB and the argon plasma is studied by a high-speed camera based on the Linear Experimental Advanced Device (LEAD) in Southwestern Institute of Physics, China. It is found that the high-density SMB can extinct the plasma temporarily and change the distribution of the plasma density significantly, while the low-density SMB can hardly affect the distribution of plasma density. This can be used as an effective diagnostic technique to study the evolution of plasma density in the interaction between the SMB and plasma. Moreover, the related simulation based on this experiment is carried out to better understand the evolution of electron density and ion density in the interaction. The simulation results can be used to analyze and explain the experimental results well.</jats:p>

<jats:p>The diamond nanothread (DNT), a new one-dimensional (1D) full carbon sp<jats:sup>3</jats:sup> structure that has been successfully synthesized recently, has attracted widespread attention in the carbon community. By using the first-principles calculation method of density functional theory (DFT), we have studied the effects of 3d transition metal (TM) atomic doping on the electronic and magnetic properties of DNT. The results show that the spin-polarized semiconductor characteristics are achieved by doping Sc, V, Cr, Mn, and Co atoms in the DNT system. The magnetic moment ranges from 1.00 <jats:italic>μ</jats:italic> <jats:sub>B</jats:sub> to 3.00 <jats:italic>μ</jats:italic> <jats:sub>B</jats:sub> and the band gap value is from 0.35 eV to 2.54 eV. The Fe-doped DNT system exhibits spin-metallic state with a magnetic moment of 2.58 <jats:italic>μ</jats:italic> <jats:sub>B</jats:sub>, while the Ti and Ni-doped DNT systems are nonmagnetic semiconductors. These results indicate that the 3d TM atoms doping can modulate the electronic and magnetic properties of 1D-DNT effectively, and the TM-doped DNT systems have potential applications in the fields of electronics, optoelectronics, and spintronics.</jats:p>

<jats:p>By employing the spin resolved density functional theory, half-metallic character is investigated in Cs<jats:sub>2</jats:sub>NpBr<jats:sub>6</jats:sub> having a K<jats:sub>2</jats:sub>PtCl<jats:sub>6</jats:sub>-type structure. The results precisely predict the half-metallic behavior of Cs<jats:sub>2</jats:sub>NpBr<jats:sub>6</jats:sub>. In spin-down state it presents an indirect band gap, while in spin-up channel it turns metallic. The structure optimization confirms the half-metallic nature in ferromagnetic configuration. The calculated magnetic moment is 3 <jats:italic>μ</jats:italic> <jats:sub>B</jats:sub> toward which the main contributor is the Np atom. Furthermore, all the computed results are compared with the available experimental and theoretical values. According to the present analysis, we recommend Cs<jats:sub>2</jats:sub>NpBr<jats:sub>6</jats:sub> for spintronic applications.</jats:p>

<jats:p>The interactions of solute atoms with vacancies play a key role in diffusion and precipitation of alloying elements, ultimately influencing the mechanical properties of aluminum alloys. In this study, first-principles calculations are systematically performed to quantify the solute–vacancy interactions for the 3d–4p series and the 4d–5p series. The solute–vacancy interaction gradually transforms from repulsion to attraction from left to right. The solute–vacancy binding energy is sensitive to the supercell size for elements at the beginning. These behaviors of the solute–vacancy binding energy can be understood in terms of the combination and competition between the elastic and electronic interactions. Overall, the electronic binding energy follows a similar trend to the total binding energy and plays a major role in the solute–vacancy interactions.</jats:p>

<jats:p>Irradiation makes structural materials of nuclear reactors degraded and failed. However, the damage process of materials induced by irradiation is not fully elucidated, mostly because the charged particles only bombarded the surface of the materials (within a few microns). In this work, we investigated the effects of surface irradiation on the indirect irradiation region of the (Al<jats:sub>0.3</jats:sub>Cr<jats:sub>0.2</jats:sub>Fe<jats:sub>0.2</jats:sub>Ni<jats:sub>0.3</jats:sub>)<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> high entropy oxide (HEO) films in detail by plasma surface interaction. The results show that the damage induced by surface irradiation significantly extends to the indirect irradiation region of HEO film where the helium bubbles, dislocations, phase transformation, and the nickel oxide segregation were observed.</jats:p>

<jats:p>The dual-phase amorphous/crystalline nanostructured model proves to be an effective method to improve the plasticity of Mg alloys. The purpose of this paper is to explore an approach to improving the ductility and strength of Mg alloys at the same time. Here, the effect of amorphous phase strength, crystalline phase strength, and amorphous boundary (AB) spacing on the mechanical properties of dual-phase Mg alloys (DPMAs) under tensile loading are investigated by the molecular dynamics simulation method. The results confirm that the strength of DPMA can be significantly improved while its excellent plasticity is maintained by adjusting the strength of the amorphous phase or crystalline phase and optimizing the AB spacing. For the DPMA, when the amorphous phase (or crystalline phase) is strengthened to enhance its strength, the AB spacing should be increased (or reduced) to obtain superior plasticity at the same time. The results also indicate that the DPMA containing high strength amorphous phase exhibits three different deformation modes during plastic deformation with the increase of AB spacing. The research results will present a theoretical basis and early guidance for designing and developing the high-performance dual-phase hexagonal close-packed nanostructured metals.</jats:p>