Autocorrelation Spectra of Air-Fluidized Granular System by the NMR Spin Echo
نویسندگان
چکیده
NMR technique of modulated gradient spin echo makes possible to measure the power spectra of displacement and velocity autocorrelation functions of the air-fluidized granular beds. The obtained frequency distribution of displacement and velocity spectra at different degrees of fluidization leads to an empiric formula that well-fits to the experimental data and gives negative long-range tail of velocity autocorrelation function with a clear indication of grain caging by its neighbors and grain hopping between cagings.
منابع مشابه
Autocorrelation spectra of an air-fluidized granular system measured by NMR
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