Bolobov V.I.,St Petersburg Mining University
Combustion, Explosion and Shock Waves | Year: 2016
Experimental data on the critical pressure of ignition of titanium alloy fragments in gaseous oxygen are analyzed. The fragments are obtained after fracture of alloy samples in the dynamic mode (p2 *) and under natural convection conditions (p1 *). The results are analyzed with allowance for the heat transfer coefficients from material ignition initiators under similar conditions. Based on the shape of the experimental thermograms of plate cooling, the coefficient of heat transfer from microcraters with a juvenile surface formed due to knockout of metal particles from the plate by the high-velocity flow is found: α2 ≈ 11 kW(m2 ·K). The value of α2 is close to the value of this coefficient calculated with the use of the coefficient α1 ≈ 5 kW/(m2 · K) of heat transfer from titanium rod microfragments (with the size of the order of metal grains) formed during titanium rod fracture in oxygen under conditions of natural convection with allowance for the ratio p2 */p1 *. © 2016, Pleiades Publishing, Ltd.
Alekseev V.I.,St Petersburg Mining University |
Marin Y.B.,St Petersburg Mining University
Geology of Ore Deposits | Year: 2012
Wolframoxiolite with a sectorial distribution of components is described from Li-F granite. The ontogenetic features provide evidence for the primary origin of wolframoixiolite and geochemical evolution of the mineral-forming medium. © 2012 Pleiades Publishing, Ltd.
Shklyarskiy Y.E.,St Petersburg Mining University |
Skamyin A.N.,St Petersburg Mining University
Coke and Chemistry | Year: 2016
The capacitive compensation of reactive power in the presence of harmonic distortion in the supply voltage is considered. Such distortion may be introduced both by factors in the external grid and by factors within the enterprise. That must be taken into account in selecting systems for reducing the effect of higher harmonics on compensating capacitor banks and improving the power quality at coke plants. © 2016, Allerton Press, Inc.
Chirkst D.E.,St Petersburg Mining University |
Lobacheva O.L.,St Petersburg Mining University |
Berlinskii I.V.,St Petersburg Mining University |
Dzhevaga N.V.,St Petersburg Mining University
Russian Journal of Inorganic Chemistry | Year: 2012
Gibbs energies of formation have been determined by conductometric titration for hydroxo complexes of cerium, samarium, europium, erbium, ytterbium, and yttrium. All these elements form mono-hydroxo complexes; yttrium, erbium, and terbium also form dihydroxo complexes. The Gibbs energies of formation of lanthanide hydroxo complexes from ions have virtually equal values of -47.3 ± 0.6 kJ/mol mono-hydroxo complexes and -44.5 ± 0.5 kJ/mol for dihydroxo complexes, respectively. These values were used to estimate the Gibbs energies of formation of hydroxo complexes for the entire lanthanide series. © 2012 Pleiades Publishing, Ltd.