Terahertz time-domain spectroscopy has been used to study the dielectric relaxation of pure 4'-n-pentyl-4-cyanobiphenyl (5CB) liquid crystal (LC) and its mixtures with 10 mum SiO2 particles in the frequency range 0.2-2 THz. For the pure sample, we find that spatial inhomogeneities consisting of oriented domains, comparable in size to our probe area (~1 mm(2)), cause a large scatter in the measu...

The prolate-to-oblate shape transition of phospholipid vesicles in response to frequency variation of an AC electric field can be explained by the dielectric anisotropy of a phospholipid bilayer Abstract. The external electric field deforms flaccid phospholipid vesicles into spheroidal bodies, with the rotational axis aligned with its direction. Deformation is frequency dependent: in the low fr...

The prolate-to-oblate shape transition of phospholipid vesicles in response to frequency variation of an AC electric field can be explained by the dielectric anisotropy of a phospholipid bilayer Abstract. The external electric field deforms flaccid phospholipid vesicles into spheroidal bodies, with the rotational axis aligned with its direction. Deformation is frequency dependent: in the low fr...

The effective measuring range of an electromagnetic wave resistivity instrument used in logging while drilling (LWD) is small, and the measurement greatly influenced by dielectric constant, especially high-dielectric-constant formations. In this paper, response characteristics under a high constant are investigated numerical simulation algorithm, conversion method determined. results show that ...

The Gemant-DiMarzio-Bishop model, which connects the frequency-dependent shear modulus to the frequency-dependent dielectric constant, is reviewed and a new consistent macroscopic formulation is derived. It is moreover shown that this version of the model can be tested without fitting parameters. The reformulated version of the model is analyzed and experimentally tested. It is demonstrated tha...

Conventional metallic waveguides have several major advantages, including low propagation losses and high power transmissions in the microwave frequency range. One disadvantage of metallic waveguides is that the propagation frequency band is limited at frequencies above the cutoff frequency fc. The usable frequency range is therefore restricted to fc < f < 2fc, because the TE20 mode can exist i...

In this paper various layered planar periodic structures which provide miniaturization of planar antennas are proposed and discussed. The proposed designs are based on two concepts, reactive impedance surfaces and complementary periodic structures. In the proposed structures, complementary periodic rings and slots are patterned on the intermediate boundaries of the dielectric layers. A patch an...

Material dielectric properties are important for understanding their response to microwaves. Carbonaceous materials are considered good microwave absorbers and can be mixed with dry biomasses, which are otherwise low-loss materials, to improve the heating efficiency of biomass feedstocks. In this study, dielectric properties of pulverized biomass and biochar mixtures are presented from 0.5 GHz ...