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The scope of this expert and analytical review encompasses major achievements in the area of nonlinear geomechanics, geophysics, geomonitoring and advanced information technologies with a view to developing the natural and induced emergency prevention and response technology listed among the “national critical technologies” in the Russian Federation. The topical trends of the related R&D activities are basic research in physics and geomechanics of natural and induced failure source formation and growth in rocks and in mines, and creation of multi-layer geoinformation monitoring system for geomechanical and geodynamic safety in Russia. The authors believe that the described R&D activities may be the basis for an international multidisciplinary mega-project in geosciences: Engineering and Creation of the World’s Multi-Layer Geomechanical, Geodynamic and Environmental Safety Geoinformation Monitoring System.

The experience of engineering a small mobile compression-vacuum machine for seismic prospecting at shallow depths of 100-150 m is described. It is shown that percussion sources are preferable for shallow-depth seismic survey. The article reports laboratory and field testing data. The authors identify ways of further improvement of this class machines.

The determinants are found and the matrix is developed for rate of wear of heading machine cutting tool. Influence of rock strength on active life of heading machines is assessed. The authors describe field studies into the nature and rate of wear of cutters. The design of multiuse tangential revolving cutter of prolonged operating life is engineered and trialed. It is proposed to enhance rock cutting efficiency using a tool with a cutting wheel.

The key mechanisms of selective recovery of manganese ions from mine water by combination of chemical and electrochemical methods are studied. The authors present the efficient parameters of oxidation deposition of ions Mn²⁺ in electrolysis solutions of active chlorine forms generated in chloride-containing solutions under electric treatment and subsequent removal of dispersed phase manganese from the solutions. The mechanism of generation of dispersed phase manganese by electric treatment of acid mine water at copper-sulfide deposits is offered

The article presents studies of slime formation in processing of Vishnevogorsk columbium ore. The slime formation criterion is assumed as the presence of size grades less than 50 and 5 µm estimated from modern laser granulometer data. The optimal methods and equipment for grinding are chosen depending on rate of slime formation in final products. The studies use centrifugal and rod mills. The rod mill assures the lowest rate of slime formation. Based on the experimental results, the columbium ore pretreatment flowsheet and special ore disintegration methods have been selected. The flowsheet uses crushing machines ensuring the highest rate selectivity-inertia cone crusher and the lowest rate slime formation during milling-rod mill.

Water micro-emulsions of dibutyl xanthate as an active compound of commercial manufacture flotation agent are produced and analyzed using the methods of dynamic light scattering and zeta potential measurements. It is found that the typical hydrodynamic diameter of xanthate drops is of the order of 300 nm and their zeta potentials are negative. The effect exerted on properties of hydrophobic (pyrolytic graphite) and hydrophilic (silicon dioxide) surfaces by pretreatment with the micro-emulsions is examined using the atomic-force microscopy method and colloid probe (SiO₂ micro-sphere). The long-range high-amplitude attraction forces, probably of capillary nature, are revealed between the probe and surfaces after the contact with dixanthate for 1 min. It is supposed that these forces are conditioned by the action of gas nano-structures (nano-bubbles, nano-cavities, etc.) initiated on the surface rendered hydrophobic by dixanthate.

The industrial-level tests prove efficiency of Pseudomonas Japonica bacteria in production of copper-molybdenum bulk concentrate. Using scanning electron microscopy, it is found that adsorption of Pseudomonas Japonica bacteria takes place at the points of xanthate attachment. The infrared spectroscopy analysis shows that after treatment with the bacteria, C-O and C=S bonds vanish while valence and deformation vibrations in СН₃- and CH₂ groups become less intensive, which may be reflective of desorption of xanthate from the mineral surface.

In focus of the study are the results obtained in flotation testing of products of X-ray absorption separation that enhances 4-5 times WO₃ content of feed for the next flotation stage. The authors estimate feasibility of reducing yield of original ore screenings (non-gradable size) -6 +0 mm and its gravity concentration.

By means of a structural representation of the chemical reactivity as a condensed graph a model predicting rate constants of the bimolecular elimination reaction is derived for the first time. The model developed enables the prediction of rate constants of reactions proceeding in different solvents or water-organic mixtures at different temperatures. It demonstrates a good predictive performance: a mean square deviation of predicted values from experimental ones is less than 0.7 logarithmic units. An outlier analysis shows that prediction errors are mainly due to the imperfection of the training data containing unique reactions. The model is available for users at arsole.u-strasbg.fr.

A pyridine-diimine compound N,N'-[pyridine-2,6-diyldi( E )methylylidene]bis(4-chloroaniline) is synthesised by a Schiff base condensation of 2,6-diformylpyridine with 4-chloroaniline in methanol and characterised by spectroscopic and analytical techniques. The molecular structure of the compound is determined by the single crystal X-ray diffraction study. The compound crystallizes in the monoclinic crystal system, I 2/ c space group with unit cell parameters a = 7.0843(12) Å, b = 6.1909(11) Å, c = 36.262(6) Å, β = 91.576(3)°, V = 1589.8(5) ų and Z = 4. There is an intermolecular hydrogen bonding in the molecule resulting in a 1D hydrogen bonding chain and these hydrogen bonding chains are linked by Cl…HC(aromatic) interactions forming a 2D network. Crystal packing of the compound is determined by Cl…HC and p-p interactions. In the fluorescence emission spectra in CH₃CN, DMF, DMSO and EtOH, the compound shows only one emission maximum.