Hydrogels present significant potential in flexible materials designed for electromagnetic interference (EMI) shielding, attributed to their soft, stretchable mechanical properties and water-rich porous structures. Unfortunately, EMI shielding hydrogels commonly suffer from low mechanical properties, deficient fracture energy, and low strength, which limit the serviceability of these materials in complex mechanical environments. In this study, the double network strategy is successfully utilized along with the Hofmeister effect to create MXene/PAA (polyacrylic acid)-CS (chitosan) hydrogels and further strengthen and toughen the gel with (NH)SO solution.
View Article and Find Full Text PDFMagnetic reconnection, the rearrangement of magnetic field topologies, is a fundamental plasma process throughout the universe, which converts magnetic energy to plasma kinetic energy and results in particle energization. A current sheet is a prerequisite for the occurrence of magnetic reconnection. It has been well documented that reconnecting current sheets are prevalent in turbulent plasmas.
View Article and Find Full Text PDFMagnetic reconnection is a fundamental plasma process by which magnetic field lines on two sides of the current sheet flow inward to yield an X-line topology. It is responsible for producing energetic electrons in explosive phenomena in space, astrophysical, and laboratorial plasmas. The X-line region is supposed to be the important place for generating energetic electrons.
View Article and Find Full Text PDFMagnetotail reconnection plays a crucial role in explosive energy conversion in geospace. Because of the lack of in-situ spacecraft observations, the onset mechanism of magnetotail reconnection, however, has been controversial for decades. The key question is whether magnetotail reconnection is externally driven to occur first on electron scales or spontaneously arising from an unstable configuration on ion scales.
View Article and Find Full Text PDFMagnetic reconnection is a fundamental plasma process, by which magnetic energy is explosively released in the current sheet to energize charged particles and to create bi-directional Alfvénic plasma jets. Numerical simulations predicted that evolution of the reconnecting current sheet is dominated by formation and interaction of magnetic flux ropes, which finally leads to turbulence. Accordingly, most volume of the reconnecting current sheet is occupied by the ropes, and energy dissipation occurs via multiple relevant mechanisms, e.
View Article and Find Full Text PDFLaser-induced fluorescence (LIF) using a pulsed laser is successfully applied in an argon plasma. The laser system consists of a pumping pulse laser fixed at 532 nm and a tunable dye laser. Using a homemade Fabry-Perot interferometer, the large linewidth of the original output is reduced by one order from 4 GHz to 340 MHz.
View Article and Find Full Text PDFA new medium-sized washer gun is developed for a plasma start-up in a fully axisymmetric mirror. The gun is positioned at the east end of the Keda Mirror with AXisymmetricity facility and operated in the pulsed mode with an arc discharging time of 1.2 ms and a typical arc current of 8.
View Article and Find Full Text PDFRev Sci Instrum
September 2017
We describe a field reversed configuration (FRC) experiment featuring in-vessel θ-pinch coils and open-field-line plasmas confined in a tandem mirror. Two FRCs, formed near the west and the east mirror throats of a central cell, are ejected toward the mid-plane for colliding and merging. Each FRC consists of four groups of pulsed power supplies and four groups of coils, having diameters 35, 35, 40, and 45 cm.
View Article and Find Full Text PDFAn in situ measurement at the magnetopause shows that the quadrupole pattern of the Hall magnetic field, which is commonly observed in a symmetric reconnection, is still evident in an asymmetric component reconnection, but the two quadrants adjacent to the magnetosphere are strongly compressed into the electron scale and the widths of the remaining two quadrants are still ion scale. The bipolar Hall electric field pattern generally created in a symmetric reconnection is replaced by a unipolar electric field within the electron-scale quadrants. Furthermore, it is concluded that the spacecraft directly passed through the inner electron diffusion region based on the violation of the electron frozen-in condition, the energy dissipation, and the slippage between the electron flow and the magnetic field.
View Article and Find Full Text PDFReconnection of the self-generated magnetic fields in laser-plasma interaction was first investigated experimentally by Nilson et al. [Phys. Rev.
View Article and Find Full Text PDFNumerical simulations have predicted that an extended current sheet may be unstable to secondary magnetic islands in the vicinity of the X line, and these islands can dramatically influence the reconnection rate. In this Letter, we present the first evidence of such a secondary island near the center of an ion diffusion region, which is consistent with the action of the secondary island instability occurring in the vicinity of the X line. The island is squashed in the z direction with a strong core magnetic field.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
January 2003
It is argued that phase explosion plays an important role during high-power laser ablation. A theoretical model which includes the effect of an expanding mass plasma has been developed to describe the process of phase explosion during the interactions of a high-power nanosecond laser pulse on an aluminum target. For a laser with a 3-ns pulse duration, if the laser intensity is high enough (>or=5 x 10(10) W/cm(2)), phase explosion was found to occur after the completion of the laser pulse, but not during the process of laser energy deposition.
View Article and Find Full Text PDF