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An innovative divertor concept, the Fish Tail Divertor, is proposed in this paper, aiming at reducing the peak heat load on the tokamak divertor plate as well as that due to the edge localized modes. This new concept has been implemented in experiments to demonstrate its capability of strike point sweeping on the plate at the frequency range from ten to one hundred Hz by using an oscillating magnetic field. The strike point movement of 5-6 cm is achieved by applying a coil current of several percent of plasma current, leading to a significant reduction of heat load on the divertor target plate. The result indicates a possible application in a fusion reactor.

Resistively shunted Nb/Al–AlOx/Nb Josephson junctions have been widely used in large-scale superconducting electronics such as the single-flux quantum circuit. The critical current determines substantially the working margin of the circuit. The distribution of vortices in the niobium film around superconducting devices is also commonly suspected to degrade the performance of devices. Unfortunately, most studies on Nb/Al–AlOx/Nb Josephson junctions only present electric transport measurements. Using a magnetic force microscope, we observed the static distribution of the vortices around the junction after sweeping the current–voltage curves of the junction in-situ. The measurements showed that the distribution density of vortices affected the critical current of the junction. Furthermore, we observed an aggregation of vortices arising from the Joule heat generated by the shunt resistor. It caused an irreversible decrease in the junction’s critical current.

Podophyllotoxin (PPT) is an active natural pharmaceutical component with potent anticancer activity. However, due to its poor water solubility and serious side effects, its medical applications are limited. In this work, we synthesized a series of PPT dimers, which can be self-assembled into stable nanoparticles of 124~152 nm in aqueous solution and can significantly increase the solubility of PPT in aqueous solution. In addition, PPT dimer nanoparticles exhibited high drug loading capacity (>80%) and could store at 4°C in aqueous state with good stability for at least 30 days. In vitro release studies showed that nanoparticles with disulfide bonds (SS NPs) can quickly release (about 96.5% drug released within 24h) the conjugated drug in PBS buffer(pH=7.4) in the presence of DTT. Cell endocytosis experiments showed that SS NPs enhanced cell uptake (18.56 times higher than PPT for Molm-13, 10.29 times for A2780S and 9.81 times for A2780T) and maintained antitumor effect against human ovarian tumor cells (A2780S and resistant A2780T) and human breast cancer cells (MCF-7). In addition, the endocytosis mechanism of SS NPs was revealed that these nanoparticles were mainly up-taken by macropinocytosis-mediated endocytosis. We believe that these PPT dimer-based nanoparticles will become an alternative formula for PPT, moreover the assembly behavior of PPT dimer can be extended to other therapeutic drugs.

Motivated by the recent experimental work, pressure-induced structural transition of well-known 2D 1T-HfTe2 was investigated up to 50 GPa through the advanced CALYPSO structure search technique combined with first principles calculations. Our calculations suggest that the 1T-HfTe2 will first transform to C2/m phase at 3.6 GPa with a volume reduction of 7.6% and then to P62m phase at 9.6 GPa with a volume collapse of 4.6%. The occurrences of 3D C2/m and %. The occurrences of 3 phases were mainly originated from the enhanced Te-Te interlayer coupling and the drastic distortions of Hf-Te polyhedrons in P3 m1 phase under compression. Concomitantly, the coordination number of Hf atom increases from six in P3 m1 to eight in C2/m and eventually to nine in P62m at elevated pressure. The metallic and semimetallic nature of C2/m and P62m phases were characterized, and the evidence of the reinforced covalent interactions of Te-Hf and Te-Te orbitals in these two novel high-pressure phases was manifested by the atom-projected electronic DOS and Bader charge.

Objective. Carbon fiber (CF) is good for chronic neural recording due to the small diameter (7 µm), high Young’s modulus, and low electrical resistance, but most high-density carbon fiber (HDCF) arrays are manually assembled with labor-intensive procedures and limited by the accuracy and repeatability of the operator handling. A machine to automate the assembly is desired. Approach. The HDCF array assembly machine contains: (1) a roller-based CF extruder, (2) a motion system with three linear and one rotary stages, (3) an imaging system with two digital microscope cameras, and (4) a laser cutter. The roller-based extruder automatically feeds single CF as raw material. The motion system aligns the CF with the array backend then places it. The imaging system observes the relative position between the CF and the backend. The laser cutter cuts off the CF. Two image processing algorithms are implemented to align the CF with the support shanks and circuit connection pads. Main results. The machine was capable of precisely handling 6.8 μm carbon fiber electrodes (CFEs). Each electrode was placed into a 12 μm wide trenches in a silicon support shank. Two HDCF arrays with 16 CFEs populated on 3 mm shanks (with 80 μm pitch) were fully assembled. Impedance measurements were found to be in good agreement with manual assembled arrays. One HDCF array was implanted in the motor cortex in an anesthetized rat and was able to detect single unit activity. Significance. This machine can eliminate the manual labor-intensive handling, alignment and placement of single CF during assembly, providing a proof-of-concepts towards fully automated HDCF array assembly and batch production.

Electron-impact single-ionization (EISI) cross sections for W q+ (q = 9, 10) ions have been calculated by using the level-to-level distorted-wave (LLDW) method with emphasis on the contribution of metastable states to the total ionization cross sections. Contributions from direct-ionization (DI) and excitation-autoionization (EA) processes are taken into account. The calculated cross sections include the contributions from both the ground configuration and the long-lived metastable states with lifetimes exceeding 10−6 s. Calculated cross sections are in good agreement with experimental measurements when the influence of metastable states on the total ionization cross section are well considered.

The spindle runout of unit 2 in a hydropower plant seriously exceeded the standard during the startup test, and its main frequency was consistent with the conversion frequency, which did not meet the startup test acceptance specification. Through the analysis of the variable speed test data of the unit, it is judged that the reason for the excessive runout is the mass imbalance of the generator rotor, which affects the vibration of the shafting and the frame. A dynamic balance test analysis method is proposed to determine the counterweight weight and orientation, which is the same centrifugal force with the equivalent in the state. In this method, the weight of the trial counterweight and the total unbalanced mass is calculated by using the trial counterweight empirical formula and dynamic balance equation respectively, and the second counterweight test is carried out after calculation. Through the application in unit 2 of the power plant, the serious problem of excessive runout of the unit can be completely solved. The analysis method of the rotor dynamic unbalance test for large hydropower units proposed in this paper can provide a technical reference for similar problems.

We report the synthesis of transition-metal-doped ferromagnetic elemental single-crystal semiconductors with quantum oscillations using the physical vapor transport method. The 7.7 atom% Cr-doped Te crystals (Cr_Te) show ferromagnetism, butterfly-like negative magnetoresistance in the low temperature (< 3.8 K) and low field (< 0.15 T) region, and high Hall mobility, e.g., 1320 cm2 V-1 s-1 at 30 K and 350 cm2 V-1 s-1 at 300 K, implying that Cr_Te crystals are ferromagnetic elemental semiconductors. When B // c // I, the maximum negative MR is -27% at T = 20 K and B = 8 T. In the low temperature semiconducting region, Cr_Te crystals show strong discrete scale invariance dominated logarithmic quantum oscillations when the direction of the magnetic field B is parallel to the [100] crystallographic direction and show Landau quantization dominated Shubnikov-de Haas (SdH) oscillations for B // [210] direction, which suggests the broken rotation symmetry of the Fermi pockets in the Cr_Te crystals. The findings of coexistence of multiple quantum oscillations and ferromagnetism in such an elemental quantum material may inspire more study of narrow bandgap semiconductors with ferromagnetism and quantum phenomena., 25 pages, 25 figures

In this paper, a multi-structure needle-ring electrode argon plasma jet device was designed to investigate the influence of reactor structure parameters and discharge parameters on the length of atmospheric pressure non-equilibrium plasma jet. Specifically, the effects of the discharge voltage, the electrode gap, the distance between the end of the high-voltage electrode and the ground electrode, and the volume flow of argon on the jet length were explored. The results demonstrate that the maximum length of the plasma jet in the external environment can reach 80 mm when the inner diameter of the tube is 15 mm; the jet length first increases and then tends to be stable with the increase in the discharge voltage; the jet length presents two peaks with the increasing voltage; the end of jet appears the unstable phenomenon of ‘beating’ when the discharge voltage is high. Besides, the longer the distance between the end of the high-voltage electrode and the ground electrode, the longer the jet length. Nevertheless, the relationship between the distance and the jet length is non-linear. The jet length first increases and then decreases with the increase in the electrode gap. The phenomenon of ‘particle countercurrent’ is observed when the electrode gap and discharge voltage are relatively large. With the increase in the argon volume flow, the plasma jet length also exhibits a trend of first increasing and then decreasing. To sum up, the main factors affecting the length of the plasma jet is transport mode during the plasma transport process.

The steady-state criterion for plasma numerical simulations can be determined by the particle balance relation. In this study, we utilized a one-dimensional (1D) particle-in-cell/Monte Carlo model to investigate particle transport in a capacitively coupled plasma discharge, including particle density change, flow, generation, and loss. Our analysis revealed that the generation rate and loss rate are equivalent in both time and space, indicating a fine balance in the steady state of the discharge system. Additionally, we presented the spatio-temporal distribution and time-averaged particle transport term for electrons and ions to demonstrate how particles attain equilibrium at varying pressures. This validation method can be particularly useful in numerical simulations where determining steady state can be challenging. Our findings establish the correctness and reliability of the method.

We extend two adaptive step-size methods for solving two-dimensional or multi-dimensional generalized nonlinear Schrödinger equation (GNLSE): one is the conservation quantity error adaptive step-control method (RK4IP-CQE), and the other is the local error adaptive step-control method (RK4IP-LEM). The methods are developed in the vector form of fourth-order Runge–Kutta iterative scheme in the interaction picture by converting a vector equation in frequency domain. By simulating the supercontinuum generated from the high birefringence photonic crystal fiber, the calculation accuracies and the efficiencies of the two adaptive step-size methods are discussed. The simulation results show that the two methods have the same global average error, while RK4IP-LEM spends more time than RK4IP-CQE. The decrease of huge calculation time is due to the differences in the convergences of the relative photon number error and the approximated local error between these two adaptive step-size algorithms.

A rotorcraft needs to accurately sample the predetermined path at a low flight rate when performing atmospheric sounding tasks; thus, it is particularly critical to obtain accurate positioning and navigation information in real-time. Hence, this paper designs a multi-sensor fusion positioning and navigation algorithm for atmospheric detection of low-speed rotorcraft. The multi-sensor fusion positioning and navigation algorithm for velocity and spatial position are presented based on the Federated Kalman Filter combined with the accelerometer, Global Positioning System (GPS), and barometer. The experimental results show that the fusion algorithm result of the velocity and spatial position is closer to the actual position than a single sensor. In conclusion, this paper’s multi-sensor fusion positioning and navigation algorithm overcomes the problems of low positioning accuracy of a single sensor and cumulative errors and effectively improves positioning accuracy, real-time, and stability.

With the wide access of distributed new energy, how to quickly identify and accurately isolate the fault of distribution network is a key technical problem to be solved in the industry. Due to the numerous branches of the distribution network, the imperfect data acquisition network, and the transmission error of the transformer, there is an urgent need for new means to cope with the synchronization problem of data acquisition in different locations. To solve the above problems, firstly, the characteristics of multi terminal distribution network in case of fault are analyzed, and the automatic synchronization of protection data is realized by detecting the abrupt points of signals at different locations; Secondly, the information of each node in the distribution network is transmitted to the substation in real time through the 5G network, and the decision-making center connects the distribution lines with multiple branches for information synthesis to form a double ended line form that is convenient for calculation and comparison; On this basis, through the tanimoto waveform similarity algorithm, the correlation coefficients of current waveforms at both ends of each line are compared to determine whether they have failed, and finally a new scheme of fast protection for multi terminal distribution network suitable for distributed new energy access is formed. By building the distribution network model in PSCAD/EMTDC, the effectiveness of the proposed protection scheme under various fault scenarios is verified. Compared with the traditional over-current protection scheme, it has faster action speed and higher reliability, and has good practical value.

sCMOS sensor has broken through the technical bottleneck of high noises and low quantum efficiencies of traditional CMOS sensors. It has the advantages of high sensitivity, high dynamic ranges, low dark current, low readout noises, low power consumption, and high integration, and has gradually become the preferred detector for low-noise imaging systems. Therefore, this paper developed an imaging system with high sensitivity, a high frame rate, low noises, and low power consumption based on a sCMOS sensor. The system adopts a sCMOS image sensor GSENSE400BSI which is very suitable for the requirements of low noises and a high dynamic range in the scientific imaging field as the photosensitive element and XILINX SPARtan-6 FPGA as the control core. Two pieces of high-speed DDR3 are configured to realize ping-pong cache of image data. In the thermal vacuum experimental verification, the total power consumption of the imaging system in the imaging mode is less than 2.2W, and the temperature rise of the sensor is less than 0.1°C. During the in-orbit verification, the imaging system runs stably and the imaging status of the system is good. It has achieved effective monitoring of space targets and high-energy ray bursts and other astronomical phenomena. The image indicators meet the application requirements of commercial space-based telescopes.

The existing decoy-state quantum key distribution (QKD) beating photon-number-splitting (PNS) attack provides a more accurate method to estimate the secure key rate, while it still considers that only single-photon pulses can generate secure keys in any case. However, multiphoton pulses can also generate secure keys if we can detect the possibility of PNS attack in the channel. The ultimate goal of this line of research is to confirm the absence of all types of PNS attacks. In particular, the PNS attack mentioned and detected in this paper is only the weaker version of PNS attack which significantly changes the observed values of the legitimate users. In this paper, under the null hypothesis of no weaker version of PNS attack, we first determine whether there is an attack or not by retrieving the missing information of the existing decoy-state protocols, extract a Cauchy distribution statistic, and further provide a detection method and the type I error probability. If the result is judged to be an attack, we can use the existing decoy-state method and the GLLP formula to estimate the secure key rate. Otherwise, the pulses with the same basis received including both single-photon pulses and multiphoton pulses, can be used to generate the keys and we give the secure key rate in this case. Finally, the associated experiments we performed (i.e., the significance level is 5%) show the correctness of our method.

Based on five different constitutive models, the progressive failure process of deep hard rock was simulated, and the plastic zone, shear strain increment high-value zone, horizontal displacement, and maximum principal stress distribution of surrounding rock were obtained. The calculation results show that the plastic zone of surrounding rock calculated by MCSS and HBSS models is mainly concentrated in the floor and vault of the cavern, and the sidewall is not damaged. There is no shear zone in the surrounding rock, and the magnitude of horizontal displacement is 10-4. In the L-CWFS model, the hysteresis cohesion of friction strengthening is weakened, and the initial friction angle is 0. The calculated plastic zone runs through the surrounding rock, and the whole section is destroyed. The order of magnitude of the horizontal displacement extremum is 10-3. The MC-HB model simulates the spalling failure of the side wall, and the strain localization of the side wall is not obvious, and no shear band is formed inside the surrounding rock deeply. The N-CWFS-TSS model simulates the buckling failure process of the straight wall plate crack. A shear band is formed at the bottom of the straight wall and penetrates into the interior of the surrounding rock. The strain localization is obvious and the order of magnitude of the shear strain increment is 10-2. The calculation results are consistent with the results of laboratory tests and field observations, and the failure mechanism of the compression-shear-tensile-shear composite in the progressive failure process of the surrounding rock is clarified.

In the course of maintenance and repair, the railway workshops of the Lan-Qing railway found that the slide plate was prone to injury and damage. In order to study the actual stress state of the slide plate during the running of the train, a finite element model of the slide plate and related components was established based on ANSYS, Hypermesh was used for meshing and mesh quality control, and the Mooney-Rivlin constitutive intrinsic model was selected to simulate the rubber plate. The stress state of the slide plate when passing through the turnout in the straight and lateral directions is analyzed respectively. The results show that there is stress concentration at the root of the tongue depressor of the slide plate, and large deformation exists in the middle of the base plate, the front end of the platform plate and the position of the guide iron when passing through the turnout directly and laterally. The stress state of the slide plate is simulated when the rail brace fails, and the maximum stress is found to be 279.24 MPa, which exceeds the material yield limit. Therefore, we should pay attention to the inspection of the condition of the rail brace during the maintenance and repair. Presenting cracks at the weld seam location, it is found that the crack has a significant effect on the dewelding of the slide plate, and the heel position is the weakness of the slide plate. When the crack length reaches 1.2 mm, there is a tendency to crack at the weld seam position of the slide plate, and when the crack length continues to increase, the crack will further expand and jeopardizing structural safety. The research results can provide a theoretical basis for the improvement, disease prevention and maintenance of the slide plate.

In this work, we present a detailed study of the electrical properties of stacked NbN/(TaN/NbN) N Josephson junctions. Cross-sectional scanning transmission electron microscopy analysis of the 5-stacked junction shows that the multilayer interface is very flat, each barrier has the same thickness, and the sidewalls of the junctions are nearly perpendicular to the substrate. Stacked junctions of different sizes and stacking numbers all have only one transition in their current–voltage curves. This indicates that the critical currents of the junctions in the stacked junctions are almost the same, showing the stability and repeatability of the multilayer fabrication and etching process. At 4.2 K, the 4-stacked junction shows excellent Josephson properties with characteristic voltage V c of 3.54 mV, which is about four times the 0.88 mV of the single junction. The temperature dependence of critical current density J c and V c of the stacked junction with N = 1, 2, 4 were measured, all of which can be fitted with dirty-limit theory. Stacked junctions with larger V c or more stacked layers can be achieved by optimizing electrode and barrier thickness, barrier resistivity, and thermal relaxation rate, etc.

Aiming at the lack of research on quantitative evaluation of satellite on-orbit operation risk, this paper from two aspects: the special features and general quality characteristics analysis and identify factors that influence the satellite provide services, and on the basis build satellite on-orbit operation risk comprehensive evaluation index system. By combining analytic hierarchy process (AHP) and satellite availability evaluation model, this paper complete the research on comprehensive evaluation of satellite on-orbit operation risk. The results of the case show that the satellite is in good operating condition and capable of providing services normally. Thus, this method can realize the comprehensive quantitative evaluation of the actual operational risks of satellites on-orbit, find out the weak points of risks according to the evaluation results, and provide effective support for the operational health management of satellites on-orbit.

High-pressure structure transition of nontoxic all-inorganic MHP CsSnBr3 was fully explored up to 15 GPa using an advanced structure search technique CALYPSO combined with first-principles calculations. Besides the known orthorhombic Pnma ground state phase, two high-pressure semiconducting Cmcm and P21/m phases of CsSnBr3 were firstly uncovered above 2.37 and 6.8 GPa, respectively. Both phase transitions of the Pnma → Cmcm at 2.37 GPa and Cmcm → P21/m at 6.8 GPa were characterized as first order with a volume reduction of 4.7% and 10.8%. The occurrences of high-pressure Cmcm and P21/m phases follow the enhanced distortions of Sn–Br polyhedrons and increased coordination of Sn atoms from 6 to 8 at elevated pressures. Compared to the direct band gap of the ambient-pressure Pnma phase, the Cmcm and P21/m phases exhibit a larger indirect band gap of 2.347 and 3.143 eV, respectively, originating from the movement away from the Fermi level of conduction bands driven by the twisting of Sn–Br polyhedrons under pressure. The light absorption performances of two high-pressure phases in comparison with the Pnma phase were studied by the calculated optical absorption coefficients.

Recently, deep learning has been widely used for intelligent fault diagnosis of rolling bearings due to its no-mankind feature extraction capability. The majority of intelligent diagnosis methods are based on the assumption that the data collected is from constant working conditions. However, rolling bearings often operate under variable working conditions in the real diagnosis scenario, which reduces the generalization capability of the diagnosis model. To solve this problem, a self-adaptive deep residual shrinkage network with a global parametric rectifier linear unit (DRSN-GPReLU) is proposed in this paper. First, the DRSN is used as the basic architecture to improve the anti-noise ability of the proposed method. Then, a novel activation function—the GPReLU—is developed, which can achieve better intra-class compactness for vibration signals, and the inter-class samples are better mapped into remote areas. Finally, a sub-network based on the attention mechanism is designed to automatically infer the slope of the GPReLU. Various experimental results demonstrate that the DRSN-GPReLU can realize better performance compared with traditional methods under variable working conditions, and has better robustness under noise interference.

Storage of a single magnetic flux quantum in a superconducting loop containing a Josephson junction represents a promising unit cell configuration for construction of a cryogenic memory of superconducting digital circuits. However, application of a DC bias current is required for operation of such a memory cell to maintain trapping of the flux quantum in the storage loop. In this work, we present a superconducting memory cell that uses a superconducting-magnetic π junction. The cell characteristics show flux quantum hysteresis centering at the zero-bias current. We develop a fabrication process that combines superconductor–ferromagnet–superconductor (SFS) junctions with superconductor–normal metal–superconductor (SNS) junctions. The critical current density of the SFS junctions shows a 0–π oscillation as a function of the ferromagnetic layer thickness. The formation of the π junction is confirmed further by the flux modulation curves of a superconducting quantum interference device made from SNS junctions with an additional SFS junction.

This study investigates the evolution of superconducting properties as a function of disorder in epitaxial and polycrystalline niobium nitride (NbN) thin films grown on MgO and SiO2/Si substrates, respectively. By reducing the film thickness from 100 to 4 nm, the effective disorder in these two sets of films encompasses a large range, with the Ioffe–Regel parameter in the range of 5.7–9.3 and 1.5–3.0, respectively. Moreover, the density of states at the Fermi level [N(0)] of epitaxial NbN films decreases from 1.91 × 1028 to 1.46 × 1028 states eV−1m−3 with the superconducting transition temperature (Tc ) ranging from 16.0 to 11.8 K. In contrast, the N(0) of polycrystalline NbN films decreases from 2.18 × 1028 to 1.80 × 1028 states eV−1m−3 with Tc ranging from 14.9 to 2.56 K. The experimental results reveal that the Tc of NbN films with different thicknesses is mainly controlled by N(0), and the greater Coulomb pseudopotential (μ*) in the polycrystalline films leads to lower Tc and larger resistivity. The changes in N(0) and μ* should collectively account for the reduction of Tc with disorder in NbN thin films.

The influence of Dzyaloshinskii–Moriya interaction (DMI) on the vortex reversal driven by an out-of-plane spin-polarized current in an off-centered nanocontact structure is investigated. The simulation results show that DMI plays a vital role in vortex core reversal, including reversal current density, reversal velocity and reversal time. Under the influence of DMI, magnetic vortices still reverse polarity through the nucleation and annihilation of vortex and anti-vortex, with some peculiar characteristics. These results open up new possibilities for the application of magnetic vortex-based spin-transfer encryption nano-storage.

A pin-on-disk high temperature wear tests under 50–150 N and 50, 100 r min−1 at 400 °C–600 °C were performed for a typical tungsten-system hot-working die steel (AISI H21). The results demonstrated that H21 steel presented different wear behavior and wear resistance under various sliding conditions at 400 °C–600 °C. In most cases at 400 °C–500 °C, H21 steel possessed good wear resistance. However, regardless of sliding speed, the wear performance of H21 steel started to deteriorate under 150 N at 500 °C, and totally deteriorated at 600 °C, exhibiting extremely poor wear resistance. A particular wear failure mechanism was found to be brittle-induced wear failure.

For the planning problem of Unmanned Aerial Vehicle (UAV) formation configuration transformation, a formation configuration transformation planning method based on the improved Hungarian algorithm is proposed. By selecting a straight-line path as the movement path of UAVs in configuration transformation, the configuration transformation problem is transformed into a multi-UAV position assignment problem with constraint handling in a dynamic environment. For the Hungarian algorithm efficiency matrix power function treatment, the improved algorithm can be simultaneously bivariate integrated optimization; Introduce the time axis in the configuration space to establish the configuration-time space, and analyze the collision constraints during the dynamic transformation process in this space, and finally, the feasibility of the method is verified by simulation.

Etching of the cathodes in magnetron sputtering determines the plasma discharge properties and deposition efficiency. In high-power and high-ionization discharges, etching becomes more complicated, resulting in inaccurate results if the conventional models are still used. This work aims at establishing an accurate dynamic model for high-power and high-ionization discharges by combining the cellular automata (CA) method and particle-in-cell/Monte Carlo collision (PIC/MCC) method, in which all the interactions pertaining to the etching morphology, plasma density, electric field, and magnetic field are considered. In high-power discharges such as continuous high-power magnetron sputtering (C-HPMS), strong self-sputtering and intense gas rarefaction stemming from the high temperature in the vicinity of the target influence the etching behavior. Compared to the experimental results, the morphology simulated by the dynamic etching model shows an error of only 0.8% in C-HPMS, which is much less than that obtained by the traditional test-electron Monte Carlo (MC) method (10.1%) and static PIC/MCC method (4.0%). The dynamic etching model provides more accurate results to aid the development and industrial application of HPMS.

Superconducting circuits based on Josephson junctions have the potential to achieve high speed and ultra-low power consumption, but their integration is limited by the low controllability of Nb-based tunnel junction and the existence of shunt resistors. In this work, we report the fabrication of superconductor/normal metal/superconductor (SNS) Josephson junctions with high reproducibility on oxidized Si substrates. The junctions based on NbN/TaN/NbN trilayers measured at 4.2 K show excellent Josephson properties with a wide range of critical current (I c) from 227 to 2000 μA. The variations of critical current density (J c) and characteristic voltage (V c) are respectively less than 7.1% and 7.5% in the 2 inch region. The standard deviation of I c is calculated to be less than 1.7% for Josephson arrays with the number of junctions up to 10 000 occupying an area of 0.34 mm2. The results provide a guarantee for the applications of NbN-SNS Josephson junctions in superconducting large-scale integrated circuits.

Aluminium-based silicon carbide (SiCp/Al) composites are widely used in spacecraft structures due to their excellent properties. Aiming at the high-precision machining requirements of thin-walled shell components installed in SiCp/Al shafting in aerospace field. The structural characteristics of thin-walled shell components are analysed. Combined with material characteristics and mechanical properties, a single clamping vertical horizontal conversion machining scheme is formulated. Match the right machine tools and PCD tools. Then the metal cutting process is simulated by AdvantEdge, and the tool structure parameters and cutting process parameters are optimized. Finally, the process route suitable for installing housing components is formulated, with dimension accuracy of H6, cylindricity of 0.003mm and coaxiality of 0.006mm, which solves the difficult problem of machining high-precision shaft mounting housing.

Although surround view systems have been widely used in advanced automotive, processing speed is still a bottleneck for the embedded system. This paper presents a 3D surround-view algorithm suitable for embedded platforms. Using methods such as extracting regions of interest (ROI) and HSV color screening to improve the efficiency of image registration, there is no need to manually select feature points, which reduces the difficulty of operation. In addition, we designed a bowl-shaped three-dimensional model to be used as a projection surface. In terms of optimization, methods such as look-up table (LUT) and hardware acceleration significantly reduce computational time.

Smart windows with tunable optical properties that respond to external environments are being developed to reduce energy consumption in buildings. In the present study, we introduce a new type of 3D printed hydrogel with amazing flexibility and stretchability (as large as 1500%), as well as tunable optical performance controlled by surrounding temperatures. The hydrogel on a PDMS substrate shows transparent-opaque transition with high solar modulation (ΔT sol) up to 79.332% around its lower critical solution temperature (LCST) while maintaining a high luminous transmittance (T lum) of 85.847% at 20 °C. In addition, selective transparent-opaque transition above LCST can be achieved by patterned hydrogels which are precisely fabricated via a projection micro-stereolithography based 3D printing technique. Our hydrogel promises great potential applications for the next generation of soft smart windows.

A large amount of radioactive waste liquid is generated in the spent fuel reprocessing process, and high-level waste is stored in a high-level waste tank. During storage, a hydrogen explosion accident may occur, resulting in the leakage of radioactive materials. This article reviewed the basic situation of high-level waste liquid and high-level waste storage system. The safety analysis of the hydrogen explosion accident was conducted, from the source and generation mechanism of hydrogen, the accumulation process of hydrogen in the tank, the possible ignition source and the possibility of explosion in the tank, the pressure generated by the hydrogen explosion, and the probability of tank failure due to hydrogen explosion are discussed. Suggestions were made on the design, operation, and safety analysis of high-level waste tanks in China, which provided a reference for the safe development of high-level waste storage facilities in commercial reprocessing plants.

Steel drums or boxes are used to transport, store, and dispose of low- and intermediate-level waste. According to relevant standards, before the solid waste container design is finalized, a series of type tests should be performed, including leakage test, water spray test, stacking test, penetration test, free-drop test, etc. This article focuses on the acceptance test and test methods for the LID- II b type waste drum finalization test. The tests in accordance with the standard requirements are the first time reported in China. It found the inherent design defects, and had high guiding significance to improve design and test verification operation.

Dry lithography is a promising micro-/nanomanufacturing method owing to its advantages of being solution-free, its absence of undercut and resistance to swelling. However, heat-mode resists suitable for dry lithography are less reported. This work reports on the use of Ag-doped Sb2Te thin film as a heat-mode resist, and its etching selectivity and microstructures are investigated in detail. It is found that Ag1.44Sb2.19Te thin film possesses high etching selectivity in CHF3/O2 mixed gases and can act as a heat-mode resist. In order to elucidate the mechanism of high etching selectivity, the microstructures of the Ag-doped Sb2Te thin films are analyzed using x-ray diffraction, Raman spectra, x-ray photoelectron spectroscopy, and transmission electron microscopy methods. The results show that the etching selectivity is attributed to the phase separation of Ag1.44Sb2.19Te film and the formation of the Sb phase after laser exposure, leading to a reduction in etching resistance in CHF3/O2 mixed gases. In addition, pattern transfers from Ag1.44Sb2.19Te to SiO2 and Si substrates are achieved successfully and the etching selectivities of Si and SiO2 to Ag1.44Sb2.19Te are both higher than 2:1. This work may provide a useful guide for the research of dry lithography without wet development.

We demonstrate enhancing the excitation and transmission efficiency of the propagated surface plasmon (SP) of an Ag nanowire (Ag NW) in hybrid Ag–MoS2 structures by contrasting the SP propagation of the Ag NW on different substrates, including SiO2 and monolayer MoS2, or partially overlapping the Ag NW on MoS2 flakes. The simulation results show that the leaky radiation of the hybrid plasmonic modes H1 and H2 can be prominently suppressed due to the high refractive index dielectric layer of MoS2, which provides an optical barrier for blocking the leaky radiation, resulting in reduced propagation loss. This paper provides a feasible and effective method to improve the SP propagation length.

We investigate theoretically Rabi-like splitting and Fano resonance in absorption spectra of quantum dots (QDs) based on a hybrid QD-semiconducting nanowire/superconductor (SNW/SC) device mediated by Majorana fermions (MFs). Under the condition of pump on-resonance and off-resonance, the absorption spectrum experiences the conversion from Fano resonance to Rabi-like splitting in different parametric regimes. In addition, the Fano resonances are accompanied by the rapid normal phase dispersion, which will indicate the coherent optical propagation. The results indicate that the group velocity index is tunable with controlling the interaction between the QD and MFs, which can reach the conversion between the fast- and slow-light. Fano resonance will be another method to detect MFs and our research may indicate prospective applications in quantum information processing based on the hybrid QD-SNW/SC devices.