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Voyager 1 occasionally detected sudden jumps of the local interstellar magnetic field strength since its heliopause crossing in August 2012. These events were believed to be associated with outward propagating solar wind shocks originating in the inner heliosphere. Here we investigate the correlation between interstellar shocks and large‐scale solar wind events by means of numerical MHD simulation. The solar wind is simplified as a symmetric flow near the equatorial plane, and the interstellar neutrals are treated as a constant flow with a fixed density distribution along the upwind direction of the local interstellar medium. The charge exchanges between the solar wind plasma and the interstellar neutrals are taken into account. At a heliocentric distance of 1 AU, the solar wind data from OMNI, STEREO A and B during the period between 2010 and 2017 are used as the inner boundary conditions to drive the simulation. The simulation results showed that the solar wind gradually merges into large‐scale structures as the radial distance increases, consistent with observations by New Horizons. After propagating into the inner heliosheath, the shocks are fully developed and the corresponding pressure pulses roughly agree with the observations by Voyager 2 in the inner heliosheath. The arrival of the shocks beyond the heliopause is estimated and found to be consistent with the observed signatures of interstellar shocks by Voyager 1. The possible origins of interstellar shocks in the inner heliosheath are discussed based on the simulation. The possible linkage was discussed based on the simulation between the pressure pulses observed by Voyager 2 in heliosheath and the shock events detected by Voyager 1 in interstellar space.The solar wind data from OMNI, STEREO A/B were jointly used as the inner inputs at 1 AU for the simulation.The one‐year periodical variation of solar wind was reproduced as a comparison with the observation from New Horizons. The possible linkage was discussed based on the simulation between the pressure pulses observed by Voyager 2 in heliosheath and the shock events detected by Voyager 1 in interstellar space. The solar wind data from OMNI, STEREO A/B were jointly used as the inner inputs at 1 AU for the simulation. The one‐year periodical variation of solar wind was reproduced as a comparison with the observation from New Horizons.

Background: Recently, core-shell typed electrorheological particles have been developed and become a research focus. In this work, monodisperse polystyrene/poly(2-methylaniline) core-shell microspheres were prepared and the shell morphology were adjusted to either smooth or urchin-like. Therefore, the influence of surface morphology on electrorheological effect was studied by comparing the electrorheological properties of the two kinds of core-shell microspheres. Methods: The surface morphology of microspheres was adjusted by using different initiators and the products were observed by scanning electron microscopy. Their electrorheological properties were tested by a rotational rheometer. Results: Sea urchin-like shells can be obtained by using iron (III) nitrate nonahydrate as an initiator. While ammonium persulphate could generate a high density of polymerisation centres, and smooth surfaces can be readily formed. In the shear flow curves, the sea urchin-like particles showed much higher shear stress than the particles with smooth surface. In the dynamic sweep tests, the sea urchinlike particles exhibited broader linear viscoelastic region and higher storage moduli under electric field. Conclusion: The low oxygen potential of the ferric salt leads to the growth of poly(2-methylaniline) nanofibres, while ammonium persulphate with a higher oxygen potential tends to form a smoother surface. The sea urchin-like polystyrene/poly(2-methylaniline) particles showed higher electrorheological properties. This indicates that the sea urchin-like particles can generate larger drag force and interparticle friction due to the rough surface and larger surface area of the sea urchin-like particles.