Articles you may be interested inEnhanced dielectric performance of three phase percolative composites based on thermoplastic-ceramic composites and surface modified carbon nanotube Appl. Phys. Lett. 106, 012902 (2015); 10.1063/1.4904937Numerical investigation on the influence factors of the electrical properties of carbon nanotubes-filled composites Effect of filament aspect ratio on the dielectric response of multiwalled carbon nanotube composites Electromagnetic characteristic and microwave absorption properties of carbon nanotubes/epoxy composites in the frequency range from 2 to 6 GHzThe DC electrical conductivity, percolation threshold, and dielectric properties of Graphene Nanoplatelets (GNPs) filled epoxy composites are studied and correlated with microwave absorption. The properties of GNPs filled composites are also compared with multiwalled carbon nanotubes (MWCNTs) composites, and GNPs are observed to have superior conductivity than MWCNTs. In all batches, the nanofillers have 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, and 3.5 wt. %. All composites irrespective of the type of nanofiller and viscosity of the matrix have shown electrical percolation threshold at 3.0 wt. %. The dielectric properties, i.e., complex permittivity, tan loss, and AC conductivity, are studied in 100 Hz-5.5 MHz. The DC and AC electrical conductivities (at and below the percolation) measured in 100 Hz-5.5 MHz are correlated to the GNPs and MWCNTs epoxy composites in the microwave frequency range (11)(12)(13)(14)(15)(16)(17). The maximum return loss of À12 dB and À6 dB was determined for MWCNTs and GNPs, respectively. The effects of nanofiller shape and the viscosity of the matrix on the dispersion and interparticle spacing of the conductive fillers within the polymer matrix have been discussed based on the results of conductivity, dielectric, and absorption properties. V C 2015 AIP Publishing LLC.

Formation of the metal complexes of aspartic acid (Asp) with the chromium metal ion (Cr 3+ ) in solutions using potentiometric titrations is presented within a wide pH range (∼3.5 to ∼10.5) at 25 • C and I = 0.10 M NaNO 3 . Concentration distribution diagrams revealed that the main complex formed within this pH range is the bis Cr 3+ complex. Literature stability constant values for the Cr-Asp complexes were used to construct concentration distribution diagrams. Complexes taken into consideration were the simple one-to-one complex, the bis-complex, and the bis-mono-protonated complex, namely, Cr-Asp, Cr(Asp) 2 , and Cr(Asp) 2 H. The corresponding Log β values of these complexes were 12.46, 21.86, and 24.30, respectively. UV-Vis spectra demonstrate Cr 3+ -Asp binding. The UV-Vis spectra were collected from a system that reached a high level of equilibrium state (50 days' equilibrium time).