This paper presents a theoretical framework describing the thermodynamics and phase transformations of a three phase component system consisting of ice particles, liquid droplets and water vapour. The instant rates of change of water (q w ), ice (q i ) and vapour (q v ) mixing ratios are described based on the quasi-steady approximation. The local thermodynamic conditions required for the equilibrium of liquid (q w = 0), ice (q i = 0) and vapour (q v = 0) phases are analysed. It is shown that there are four different regimes of the partitioning of water between liquid, ice, and gaseous phases in mixed clouds. The Wegener-Bergeron-Findeisen (WBF) process is identified as being relevant to two of those regimes. The efficiency of the WBF process in characterizing the capability of ice crystals to deplete the water evaporated from liquid droplets is introduced here. It is shown that the WBF process has maximum efficiency at approximately zero vertical velocity. The analysis of the dependences ofq w ,q i andq v on the vertical velocity, temperature, pressure and the integral radii of the cloud particles is presented. It is shown that the maximum rates of ice growth and droplet evaporation do not necessarily occur at T = −12°C where the maximum difference between saturation vapour pressure over ice and that over liquid is observed.

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Crystal structure investigations, electrical resistivity, and magnetic measurements have been performed for polycrystalline samples of intercalated compounds Cr(x)TiTe(2) with a Cr concentration up to x = 0.65. According to the room-temperature x-ray diffraction study of Cr(x)TiTe(2), the initial hexagonal crystal structure transforms to a monoclinic one with increasing Cr content up to x≥0.5 due to the ordering of Cr ions. The intercalation results in the change of the resistivity behavior in Cr(x)TiTe(2) from metal-like at x = 0 to insulator-like above x = 0.33 and leads to ferromagnetic ordering of Cr magnetic moments at x≥0.5. For the compound Cr(0.25)TiTe(2), structural transformations and anomalous resistivity behavior are observed around 230 K, which cannot be explained only by the order-disorder transition within the subsystem of intercalated Cr ions. Structural changes within Te-Ti-Te sandwiches associated with charge density wave instability are suggested to be involved in this phase transition as well.

The temperature dependences of the resistivity, Hall coefficient, and magnetic susceptibility of iron-vanadium-aluminum alloys have been investigated. It has been established that the alloy Fe1.9V1.1Al exhibits semiconductor behavior for the method used to obtain uniform alloys. It is shown that at temperatures below 30K the semiconductor alloy possesses the characteristic low-temperature scale of the dependences observed, which could be responsible for the appearance of a narrow pseudogap in the electron density of states. A simple theoretical description of the effects of a pseudogap is proposed. A consistent fit of the theoretical to the experimental relations made it possible to determine the effective width of the pseudogap (∼1MeV) and its relative depth (∼102).