Biological activity and physicochemical properties of thermally activated water types: Mollusk-based bioassay

Physicochemical and bioassay methods are used to carry out a comprehensive study of the properties of two types of activated waters: “thermally activated,” i.e., thermal water, referred to as “white spring” or “cold boiling water” in folk medicine, and “melt” water after quick freeze. The test object for bioassay were apple shell mollusks Pomacea canaliculata from a laboratory culture used to carry out patented and widely tested methods of freshwater quality bioassay. Oxygen and hydrogen peroxide concentrations and pH were determined in water. The integral biological activity of water was evaluated by a method based on the use of absorption spectra to evaluate the rate of redox transformation in the quinone-hydroquinol system. Similar studies were carried out with three types of reference samples: settled original tap water, the same water cooled to the freezing point, and water artificially enriched with hydrogen peroxide. The water activated by thermal impact has been found to have higher biological activity than the original tap water.     

Non-stationarity parameters of open clusters

Estimates of a number of dynamical parameters of 103 open star clusters are presented: the density contrast in the cluster core, stellar velocity dispersion, taking into account the influence of the external field of the Galaxy and non-stationarity of the cluster, oscillation periods of the cluster and the cluster core, etc. Analytical solutions to the gross dynamical equations are obtained for simple cluster models. These solutions are used to estimate a number of quantities characterizing the degree of non-stationarity of the cluster, such as the amplitude of oscillations of the cluster virial coefficient and of the radius of the cluster core, etc. Astrophysical applications of these results are discussed.     

Correlations, spectra, and instability of phase-space density fluctuations in open-cluster models

The dynamical evolution of six open star cluster models is analyzed using the correlation and spectral analysis of phase-space density fluctuations. The two-time and mutual correlation functions are computed for the fluctuations of the phase-space density of cluster models. The data for two-time and two-particle correlations are used to determine the correlation time for phase-space density fluctuations ((0.1–1) τ _v.r., where τ _v.r. is the violent relaxation time of the model) and the average phase velocities of the propagation of such fluctuations in cluster models. These velocities are 2–20 times smaller than the root mean square velocities of the stars in the cluster core. The power spectra and dispersion curves of phase-space density fluctuations are computed using the Fourier transform of mutual correlation functions. The results confirm the presence of known unstable phase-space density fluctuations due to homologous fluctuations of the cluster cores. The models are found to exhibit a number of new unstable phase-space density fluctuations (up to 32–41 pairs of fluctuations with different complex conjugate frequencies in each model; the e-folding time of the amplitude growth of such fluctuations is (0.4–10) τ _v.r. and their phases are distributed rather uniformly). Astrophysical applications of the obtained results (irregular structure of open star clusters, formation and decay of quasi-stationary states in such clusters) are discussed.     

Lake ice simulation using a 3D unstructured grid model

Ocean Dynamics - We develop a single-class ice and snow model embedded inside a 3D hydrodynamic model on unstructured grids and apply it to lake studies using highly variable mesh resolution. The...