AVALIAÇÃO CLÍNICA E TOPOGRÁFICA DOS PACIENTES DIAGNOSTICADOS COM ACIDENTE VASCULAR CEREBRAL NO SERVIÇO DE EMERGÊNCIA

Abstract

A nanoscale core-shell structure of β-SiC P -Ni was prepared at lower temperature by a simple and convenient electroless plating approach. The core-shell nanoparticles were characterized by means of XRD and TEM. The results show that β-SiC nanoparticles (β-SiC P ) are coated by a uniform and continuous nickel shell. The mechanism based on the theory of electroless plating and palladium catalysis was discussed in details about core-shell structure of β-SiC P -Ni. Dielectric permittivities of the original silicon carbide nanoparticles (β-SiC P ) and nickel-coated β-SiC P in paraffin wax were measured respectively in the GHz frequency range from 8 to 12 GHz. The real part and dielectric loss tangent of the nickel-coated β-SiC P were significantly enhanced. The origin of the enhancement was discussed in theory, and also explained by discussing the change of surface electrical conduction behavior of β-SiC P and nickel-coated β-SiC P .