New method for the synthesis of metal complexes based on PtIV and substituted nicotinamides and isonicotinamides and investigation of their antimetastatic activity

Complexes of platinum tetrachloride with substituted nicotinamides and isonicotinamides were synthesized by the reactions of the corresponding amides with hexachloroplatinic acid. All these complexes are low-toxic. The strong antimetastatic activity of these complexes against Lewis lung carcinoma and B16 melanoma experimental tumors was found in an enzyme system and was then shown in experiments on animals.     

Hydroxamic acids: synthesis and adjuvant activity in combinatorial anticancer therapy

Russian Chemical Bulletin - Monoand disubstituted N-hydroxyamides of dicarboxylic acids were prepared by reaction of dicarboxylic acids or acid anhydrides with hydroxylamine. The use of these...     

Key thermodynamic characteristics of nucleation on charged and neutral cores of molecular sizes in terms of the gradient density functional theory

The gradient density functional theory and the Carnahan–Starling model formulated for describing the contribution of hard spheres have been used to calculate the profiles of condensate density in small critical droplets formed via homogeneous nucleation, as well as in stable and critical droplets formed via heterogeneous nucleation on solid charged and neutral condensation cores of molecular sizes. The calculations performed for water and argon at different values of condensate chemical potential have yielded the heights of the activation barriers for homoand heterogeneous nucleation as functions of vapor supersaturation at preset system temperatures. The interaction of condensate molecules with a solid core has been described by the resultant potential of molecular attractive forces. In the case of a charged core, the long-range Coulomb potential of electric forces has additionally been taken into account. Dielectric permittivities have been calculated as known functions of the local density of the fluid and temperature. The radius of the equimolecular droplet surface has been chosen as a variable describing the droplet size. Dependences of the chemical potential of condensate molecules in a droplet on its size have been plotted for water and argon with allowance for the action of capillary, electrostatic, and molecular forces. It has been shown that the role of the molecular force potential in heterogeneous nucleation increases with the size of condensation cores.     

Structure and the emission and piezoelectric properties of MOCVD-grown ZnS,ZnS-ZnO,and ZnO films

Zinc sulfide and zinc oxide films are produced by the pyrolysis of organometallic compounds (MOCVD technique). The objects of investigation are the phase composition, structure, surface topology, and the optical and piezoelectric properties of the films obtained under different process conditions. The composition of the films depends on the purity level of the precursor, substrate temperature (as the temperature grows, the composition varies from ZnS to ZnO), and evaporation rate (with an increase in this rate, the composition changes from ZnO to ZnS). In addition, ZnS turns into ZnO upon annealing at 600°C. In the most perfect ZnS films, which are obtained with the purest precursor, intense edge luminescence (3.64 eV) is observed for the first time at room temperature. Two-phase ZnS-ZnO films obtained from a cheap precursor are characterized by pronounced piezoelectric properties and can be used in designing different piezoelectric and acoustoelectric devices.     

On the Сhoice of the Equation of State for a System of Hard Spheres in Calculations of Density Profiles and Surface Tension of Droplets and Bubbles

Russian Journal of General Chemistry - The dependences of the pressure, the chemical potential and the free-energy density on the number density of particles for a homogeneous system of hard...     

New approach to defining thermodynamic surface tension of solids

Using either the chemical potential of the immobile component of a solid dissolved in a fluid phase or the corresponding component of the tensor of chemical potential in solid phase, a new concept of the grand thermodynamic potential of solid-fluid two-phase system is proposed. For a planar interfacial surface, this makes it possible to generalize the notion of thermodynamic surface tension σ introduced by Gibbs that has the meaning of the formation work of a unit surface. This tension is determined as the specific surface excess of the grand thermodynamic potential. This definition of the thermodynamic surface tension does not depend on the position of the dividing surface and is common for fluids and solids. It is shown that, at the arbitrary position of dividing surface, the difference between thermodynamic σ and mechanical @[gamma] surface tensions for solid surface is determined by the nonuniformity of the tensor of chemical potential in a solid, as well as by its anisotropy in the bulk of solid phase.     

Three stages of water microdroplet evaporation on hydrophobized surface: Comparison between steady-state theory and experiment

Three consecutive stages of evaporation of a sessile water microdroplet are studied both theoretically and experimentally under the conditions of contact angle hysteresis. The influence of thermal effects on the dynamics of droplet evaporation is quantitatively investigated on the basis of the obtained experimental results. The features of droplet evolution are analyzed at the final stage, when both the contact angle and the radius of the droplet base decrease with time. It is shown that evaporation at this stage also occurs in a steady-state regime, but the average droplet temperature approaches the ambient temperature.     

The line tension and the generalized Young equation: the choice of dividing surface

Using Gibbs method of dividing surfaces, the condition of equilibrium of a sessile drop on a flat non-deformable solid substrate is investigated. The dependence of the line tension on the curvature radius of the dividing three-phase contact line is found. It has been derived a relationship between the partial derivative of the line tension with respect to the curvature radius of the three-phase contact line (which stands in the generalized Young equation) and the total derivative of the line tension with respect to the same radius along the equilibrium states. Various approximated formulas of the generalized Young equation used in the literature are analyzed.