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Published in Carl W. Hall, Laws and Models, 2018
Newton-Kelvin Model, Three Element A viscous material represented by a Kelvin model or Voigt-Kelvin model in series with a dashpot. Newton-Kelvin Model, Four Element A material represented by a Kelvin unit (model) in series with a viscous (dashpot) element and a spring (Hookean) model. Burgers Model A material represented by a Voigt model and Maxwell model in series. Keywords: dashpot, element, Hookean, material, spring, viscous BURGERS, Johannes Martinus, twentieth century (b. 1895), Dutch rheologist HOOKE, Robert, 1635-1703, English physicist KELVIN, Lord (William Thomson), 1824-1907, Scottish mathematician and physicist MAXWELL, James Clerk, 1831-1879, Scottish mathematician and physicist NEWTON, Sir Isaac, 1642-1727, English philosopher and mathematician VOIGT, Woldemar, 1850-1919, German physicist Sources: Flugge, W. 1962; NUC; Scott Blair, G. W. 1949; Vernon, J. 1992. See also BINGHAM; HOOKEAN; KELVIN VISCOELASTIC NUMBER, Vis OR NVis A dimensionless group representing dynamic viscoelasticity that relates the elastic force and viscous force: Vis = G/ where G = shear modulus of elasticity = frequency = absolute viscosity Keywords: dynamic, elastic, force, frequency Sources: Land, N. S. 1972; Potter, J. H. 1967. VISCOSITY--SEE MAXWELL; NEWTON VIS VISA CONSERVATION, LAW OF--NOW CALLED LAW OF ENERGY CONSERVATION Source: Guillen, M. 1995 See ENERGY CONSERVATION, LAW OF VOIGT EFFECT OR MAGNETIC DOUBLE REFRACTION (1898) An anisotropic substance placed in a magnetic field becomes birefringent, and its optical properties are similar to a uniaxial crystal. The transverse magneto-optic birefringence is called Voigt effect. Keywords: birefringent, crystal, magneto-optic, optical, uniaxial VOIGT, Woldemar, 1850-1919, German physicist Sources: Parker, S. 1987; Webster's Biographical Dictionary. 1959. VOIT LAW OF METABOLISM The nitrogen in food during metabolism is equivalent to the sum of the nitrogen in the urine and feces. No metabolism nitrogen is in the respiratory gases.
Investigation of photonic band gap properties of one-dimensional magnetized plasma spherical photonic crystals
Published in Waves in Random and Complex Media, 2023
Tian-Qi Zhu, Jia-Tao Zhang, Hai-Feng Zhang
From Figures 5 and 6, it can become conscious that when ωc = 0, apparent PBGs can be observed at ω/ω0=2.02, 2.60, and 2.87. At this stage, the external magnetic field is not available and the magneto-optical Voigt effect is not manifested in the plasma layer. If ωc is 0.8ωp, the position of PBG originally located at ω/ω0= 2.02 does not move significantly, but the bandwidth rises from 0.12ω0 to 0.14ω0. Homoplastically, the frequency range of the PBG initially located at ω/ω0= 2.87 is expanded from 2.87–2.94ω/ω0 to 2.87–2.96ω/ω0. Compared with the PBG located at 2.60ω0 at ωc = 0, the frequency coverage area of the PBG in the case of ωc = 0.8 is lessened. Further enhancing ωc to ωp, it can be noted that the first PBG moves from 2.02ω0 to 2.04ω0, showing a holistic trend toward the high-frequency region. And the bandwidths of the PBGs in this condition acquire elevated and the maximum value enlarges to 0.16ω0. On the side, it is evident from the dispersion curve that when ωc = 0.8ωp, a PBG emerges at ω/ω0= 2.32, which does not appear at ωc = 0. And as ωc ulteriorly increases to ωp, this PBG moves to high frequencies, accompanied by an expansion in bandwidth. Combining the above analysis, it can be concluded that for the PBGs with large bandwidth, the alteration of ωc provides a fire-new idea for the adjustment of the position and frequency range. For the PBGs having narrow bandwidths, the effect of ωc on them is dubious, which presumably gives rise to the expansion of the forbidden bands and the shift of the PBGs positions.