Akademska digitalna zbirka SLovenije - logo
VSE knjižnice (vzajemna bibliografsko-kataložna baza podatkov COBIB.SI)
  • Discontinuities in amplitudes of particles micromotions characterizing phase transitions in liquid state
    Hlaváček, B. ; Shánělová, J. ; Málek, J.
    The behavior of amorphous solids below Vogel's (T_V) or the glass transition (T_g) temperature, as well as the solid-liquid transition, have been analyzed taking into consideration the anharmonicity ... of motion of microparticles forming the amorphous bodies. The T_g transition is explained within the logical association of this transition with the higher-temperature transitions, which can eventually involve the process of particle release into the gas phase through the process of a sudden vibrational amplitude growth. It follows from the mathematical solution of the anharmonicity problems that the pulses and the double amplitudes will always be present in a liquid matrix. The T_g temperature is considered as the boundary point for the liquid state at which the dynamical microcracks of a solid state matrix start to proceed. The processes at T_g are accompanied by appearance of new, highly agitated spots and the first microcracks (vacancies) filled up with the 'semi-evaporated' particles. In the mechanical sense, these vacancies form a new particle species characterized by quite different properties (different thermal expansion coefficient) as compared with the particles of the original matrix. It is assumed that a number of new mechanical units are growing up to the critical temperature when the original liquid frame, bonding the particles to lower amplitudes, is completely destroyed. The approach proposed does not contradict the traditional views reflected in the famous Adam-Gibbs-Di Marzio or WLF approaches, but allows a different approach to these theories.
    Vir: Mechanics of time-dependent materials : an international journal devoted to the time-dependent behaviour of materials and structures. - ISSN 1385-2000 (Vol. 3, no. 4, 1999, 351-370)
    Vrsta gradiva - članek, sestavni del
    Leto - 1999
    Jezik - angleški
    COBISS.SI-ID - 3841307

Vnos na polico