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This study reports an efficient electroless plating approach using an amino-alcohol precursor to synthesize the oxidation stable copper@silver (Cu@Ag) core–shell nanowires. The synthesized nanowire...

Copper nanowires and graphene (CuNWs-GNs) composites are of considerable interest for the fabrication of stable and low-cost flexible electrodes for modern electronic devices. However, their current synthetic methods are either complication, requiring special equipment, or using hazardous chemicals. In this work, we proposed a new strategy to synthesize CuNWs-GNs composite using the hydroxylated graphene (GOH) as a reducing agent and protector for the first time. The CuNWs in-situ grew between the GOH interlayers and were completely covered by the latter. This novel structure empowered excellent electrical conductivity of 2.12 × 106 S/m at a sheet resistance (Rs) value of 0.037 Ω sq−1 with extended stability over 60 days at 25 °C, and 80 °C for 7 days in different humidity. The composite also presented applicable optoelectronics properties and excellent bending stability. This approach is expected as an effective way to solve the big issue of CuNWs in terms of instability for its practical application.

The characteristics of shock train in hypersonic inlet/isolator differ from that in directconnect conditions. In order to avoid violent stream-wise and transverse oscillation in isolator, a fluidic control method were proposed. This method combines the boundary suction and the slot injection method together. For the sake of checking out the control effect of the concept, two contrast wind-tunnel experiments were completed in M0=4.92 hypersonic wind tunnel. According to the experiment results, as the shock train moving upstream, the mass flow rate of secondary flow increased and the slip line moving towards to the bottom wall, meanwhile a series of weak shocks generated by injection got stronger that increased the pressure upstream the shock train. The shock train interacted with upstream background shockwaves, and the travelling processes can be divided into 4 stages which were much simpler than that of uncontrolled flow. Although there was one unstable stage, the shock train behaved in a much milder manner with an oscillation frequency of 641Hz and the maximum oscillation power decayed to 20% of that of uncontrolled flow, and the maximum sustainable back pressure almost equal to that of uncontrolled flow.

Violent oscillation caused by unstart in a hypersonic inlet will always bring fatal damages to the flight control and structural safety of the vehicle. A new control method for the hypersonic inlet unstart caused by downstream mass-flow choking based on a movable slotplate is brought forward and investigated by computational method. First, the start and unstart flows of the two-dimensional rectangular hypersonic inlet are studied at a freestream Mach number of 4.92. The results show that the captured mass flow rate is 3.005kg/s at the started mode and the dominant frequency of oscillations is approximately 351Hz at the unstarted mode with TR=58%.Then, the movable slot-plate starts to open to let air flow spill, and when the mass flow rate of spilled reaches 1.447kg/s, the oscillation of the unstard flow vanishes. However the slot-plate has no effect on improving the inlet restart capability.