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We have studied the composition of aliphatic and aromatic fractions of bitumen of coals and carbonaceous argillites from Permian deposits of north-eastern Pechora coal basin by gas chromatography and chromato-mass-spectrometry. The composition of normal alkanes and distribution of sterane hydrocarbons in bitumen testified to that terrigenous organic matter was the main component of Permian coals from the studied area. The identification of 19-norisopimarane and retene in the bitumen composition of the Upper Permian deposits is the evidence of the contribution of coniferous plants to the initial coal biomass composition, and their irregular distribution in the section indicated a change (changes) of the species composition of conifer fossil vegetation in the Late Permian time. The evaluation of coal rank of the studied deposits by MPI-1 and MPDF values testified the coals are high to medium volatile bituminous.

Keywords: coal, deposits of Permian age, biomarkers, retene, 19-norisopimarane.

DOI: 10.19110/2221-1381-2016-3-10

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The garnet from metaultramafic rocks is considered as an important sign of UHP-HP formation conditions. Garnets were investigated from forsterite-enstatite rock and antigorite serpentinite of the eclogite-glaucophane schists Maksutovo Complex. Garnets was selected from the large samples (150—200 kg.) that were fractioned to 0.25 mm. Further, the fraction was treated to a heavy concentrate with subsequent selection from it the garnets. They have been analyzed by using a scanning electron microscope REMMA-202M with microprobe in the mode of secondary electrons.

The garnets from metaultramac rocks formed a heterogeneous community and they represented different of species pyrope-almandine, almandine, grossular-almandine and almandine-spessartine and are similar to garnets of the eclogites, garnet-clinopyroxenite and glaucophane rocks which spatially and genetically related with them. They contain inclusions of UHP-HP minerals. Low-calcium pyrope-almandine garnet reflects the processes of early metamorphic in conditions of granulite facies of metamorphism for forsterite-enstatite rocks. 
Keywords: Maksutovo Complex, garnet, forsterite-enstatite rock, antigorite serpentinite, eclogite, garnet-clinopyroxene rocks.

DOI: 10.19110/2221-1381-2016-6-11-17

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We have established that when the formation of supramolecular structures of spherical silica particles with a diameter of 220—320 nm is limited by the rate of entering of the particles into the zone of sediment formation (sediment deposition in a tube of constant cross section), the rate of particles deposition, as well as the rate of formation of the supramolecular structure, composed of them, are strictly linear. At the same time, in conditions of an excessive disperse phase in the zone of formation of the supramolecular structure (sediment deposition in a tube with a modified crosssection) the rate of deposition is also linear, but the process of formation of the supramolecular structure is delayed. The smaller the size of the disperse phase particles, the greater this delay. After the end of formation of the supramolecular structure, an area with increased concentration of the dispersed phase remains over it, which height the greater, the smaller is the particle size.

We have showed that the beginning of the formation of a supramolecular structure requires a certain concentration of the disperse phase in the disperseenvironment, below which the formation of supramolecularly ordered structure does notoccur. The value of the concentration of the dispersed phase, required to start formation of a supramolecular structure, is a constant, not changing with time; and it depends only on particle size.
Keywords: asupramolecular structure, supramolecular crystallization kinetics, monodisperse spherical silica particles, a noble opal.

DOI: 10.19110/2221-1381-2016-6-18-23

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We suggest the method to increase the radiodensity resolution of the industrial microtomographes (SkyScan). The method is based on the filter with a narrow transmission spectrum (60—90 keV with 100—130 kV source voltage). The filter is composed of lead-containing glass 2.14 mm thick.

Keywords: X-ray microtomography, spatial resolution, radiodensity, source voltage, filter, core sample.

DOI: 10.19110/2221-1381-2016-6-24-27

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We tested technologies of processing of flotation tailings by using combined flotation reagent on the example of tailings from Zhezkazgan plant and Tishinskoe deposit (Kazakhstan). The combined collector is a mixture of composite aerofloat, TS-1000 and butyl xanthate with reactant ratios 1:1:3. The advantage of the suggested flotation reagent is its composition including two polar groups and a long hydrocarbon radical. We showed that the flotation of Zhezkazgan tailings using smaller consumption of combined reagent in comparison with butyl xanthate resulted in the draft copper concentrate with copper content 13.0 % at recovery 80.22 %. In comparison with the base technology the content of copper in the draft concentrate increases at 5.1 %, and the recovery — increases at 31.4 %. At flotation of Tishinskoe deposit tailings the copper recovery into the collective concentrate increases at 9.63 %, lead — at 8.41 %; zinc — at 9.2 %. 

Keywords: flotation tailings, regrinding, extraction, recovery.

DOI: 10.19110/2221-1381-2016-6-28-32

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Bauxites from the Vezhayu-Vorykvinskoe deposit (Middle Timan, Russia) are characterized by a considerable iron content, which negatively affect the ore proccesing. Using modern instrument base for mineralogical studies the author conducted test experiments proving the changes of phase composition and magnetic properties of bauxites after thermal and radiation-thermal processing. The results will allow reconsidering technologies of bauxite processing.

Keywords: high-ferriferous bauxites, thermal processing, accelerated electron processing, magnetic properties.

DOI: 10.19110/2221-1381-2016-6-33-34

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