Preparation and characterization of foamed polyurethane/silicone rubber/graphite nanocomposite as radio frequency wave absorbing material: The role of interfacial compatibilization

A radio-frequency wave is normally incident upon an inhomogeneous plasma slab. The plasma slab is composed of partially ionized high-temperature air corresponding to the characteristics of the plasma sheath surrounding hypersonic reentry vehicles. The isotropic part of the electron velocity distribution function is Maxwellian because of electron–electron collisions. The electromagnetic wave is intense enough to heat selectively the electron gas, altering the various electron production and loss processes. The high-frequency limit is considered, and expressions are obtained for the electron number density and effective collision frequency as a function of electron temperature. The effective collision frequency takes into account the effects of electron–neutral and electron–ion collisions for momentum transfer. From an energy balance equation, the electron temperature is found to be a function of both the frequency and field strength of the wave. The electron temperature is found also to exhibit an instability that gives rise to a hysteresis effect.

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Radio-Frequency Wave Application in Esthetic Surgery of Head and Neck

Global Journal of Otolaryngology ◽

10.19080/gjo.2017.08.555741 ◽

2017 ◽

Vol 8 (4) ◽

Author(s):

Novak Vukoje

Keyword(s):

Radio Frequency ◽

Head And Neck ◽

Esthetic Surgery ◽

Frequency Wave ◽

Radio Frequency Wave

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Identification and characterization of aging products in the glyoxal/ammonium sulfate system - implications for light-absorbing material in atmospheric aerosols

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-6235-2012 ◽

2012 ◽

Vol 12 (2) ◽

pp. 6235-6262

Author(s):

C. J. Kampf ◽

R. Jakob ◽

T. Hoffmann

Keyword(s):

Ammonium Sulfate ◽

Atmospheric Aerosols ◽

Molar Absorptivity ◽

Molecular Product ◽

Product Identification ◽

Absorbing Material ◽

Identification And Characterization ◽

Absorbance Band

Abstract. In this study we report the identification of bicyclic imidazoles in aqueous aerosol mimics using HPLC-ESI-MS/MS. 2,2´-Biimidazole was identified to be a major contributor to the 280 nm absorbance band observed in mixtures of glyoxal and ammonium sulfate, despite the fact that its production rate is two orders of magnitude lower than the previously reported production rates of imidazole or imidazole-2-carboxaldehyde. The molar absorptivity of 2,2´-biimidazole was determined to be (36 690&pm;998) M−1 cm−1. This demonstrates the necessity of molecular product identification at trace levels to enable a better understanding of relevant absorbing species. Additionally the formation of lower polarity products including formamides of imidazoles is proposed. The role of imidazoles and other light-absorbing species in the formation of SOA and optical properties of SOA is discussed and potentially interesting fields for future investigations are outlined.

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