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Zhuravleva N.V.,RAS Institute of Coal Chemistry and Chemical Materials Science | Potokina R.R.,OAO Zapadno Sibirskii Ispytatel'nyi Tsentr | Ismagilov Z.R.,RAS Institute of Coal Chemistry and Chemical Materials Science
Solid Fuel Chemistry | Year: 2016

The granulometric composition of the powders of GZhO, OS, and G coals was measured by a laser diffraction method upon the dispersion of samples in an aqueous medium with the addition of a Dusazin 901 surfactant (Fritsch, Germany). The metrological evaluation of the results of determinations by coal-sizing analysis and the laser diffraction method was performed. It was shown that satisfactory results were obtained for the samples of GZhO and G coals in all of the determination ranges. For the samples of OS coal, the limit of reproducibility between the two methods in ranges of 0.074 + 0 and –0.20 + 0.10 mm was exceeded by factors of 1.5 and 1.2, respectively. © 2016, Allerton Press, Inc.


Kalenskii A.V.,Kemerovo State University | Anan'Eva M.V.,Kemerovo State University | Kriger V.G.,Kemerovo State University | Zvekov A.A.,RAS Institute of Coal Chemistry and Chemical Materials Science
Russian Journal of Physical Chemistry B | Year: 2014

The rate constant of capture of electron charge carriers on a screened repulsive center are performed. Approximate expressions for the potential barrier width, the capture cross section, and rate constant are derived. It is shown that the increase in the concentration of free charge carriers in silver azide from 1016 to 1020 cm-3 results in an increase in the capture rate constant by four orders of magnitude. It is also shown that, with increasing concentration of free carriers, the temperature dependence of the rate constant weakens and the effective activation energy of capture in silver azide decreases from 0.18 to 0.01 eV. © 2014 Pleiades Publishing, Ltd.


Aduev B.P.,RAS Institute of Coal Chemistry and Chemical Materials Science | Nurmukhametov D.R.,RAS Institute of Coal Chemistry and Chemical Materials Science | Furega R.I.,RAS Institute of Coal Chemistry and Chemical Materials Science | Zvekov A.A.,RAS Institute of Coal Chemistry and Chemical Materials Science | Kalenskii A.V.,Kemerovo State University
Russian Journal of Physical Chemistry B | Year: 2013

The results of measurements of the threshold of explosive decomposition of PETN with 0.1 wt % additives of aluminum nanoparticles under the action of the first and second harmonics of a YAG:Nd3+ laser with a pulse duration of 12 ns are presented. A comparison of experimental and theoretical results is performed. It is concluded that the absorption of radiation heats the nanoparticles to form chemical decomposition kernels in the vicinity of the hotspot, so that the initiation of explosive decomposition is not associated with optical breakdown of the sample. © 2013 Pleiades Publishing, Ltd.


Kalenskii A.V.,Kemerovo State University | Anan'eva M.V.,Kemerovo State University | Zvekov A.A.,RAS Institute of Coal Chemistry and Chemical Materials Science | Zykov I.Y.,Kemerovo State University
Technical Physics | Year: 2015

The explosive decomposition kinetics of tetranitropentaerythrite aluminum compressed pellets is studied with a high time resolution. Explosive decomposition is initiated by a pulsed 1064-nm laser with a pulse FWHM of 12 ns. Emphasis is on the prethreshold glow mode, which sets in at a pulse energy density below 1 J/cm2. The ascending part of the glow intensity curve is described by a Gaussian function with effective constant k = (1.2 + 0.2) × 108 s−1. The characteristic decay time is about 40 ns. The total glow duration does not exceed 100 ns. Explosive decomposition becomes noticeable immediately during the pulse: the induction period is absent. The initial portion of the glow intensity curve is described by a Gaussian function with effective constant k = (1.4 + 0.1) × 108 s−1. The explosive glow kinetics is biextremal. The first peak is nearly coincident with the maximum of the laser action, and the extension of the second peak is 600 ns. Experimental data are treated in terms of the prethreshold model of thermal explosion. © 2015, Pleiades Publishing, Ltd.


Kalenskii A.V.,Kemerovo State University | Zvekov A.A.,RAS Institute of Coal Chemistry and Chemical Materials Science | Nikitin A.P.,RAS Institute of Coal Chemistry and Chemical Materials Science | Anan'eva M.V.,Kemerovo State University
Russian Physics Journal | Year: 2015

Spectral dependences of the light extinction, absorption, and scattering efficiency factors of copper nanoparticles attendant to variations of their radii are calculated. A plasmon maximum is observed on the spectral dependence of the extinction efficiency factor for nanoparticle radii 10–60 nm. The maximum of the absorption efficiency factor is shifted toward red wavelengths with increasing radius of copper nanoparticles. Results are interpreted based on the special features of the spectral dependence of the complex copper refractive index. It is shown that the copper nanoparticles with radius of 35 nm placed into a transparent matrix with refractive index of 1.54 (secondary explosive pentaerythritol tetranitrate) possess a very high value of the absorption efficiency factor (2.9) of the second harmonic of a neodymium laser. Our investigations suggest that the copper nanoparticles are perspective material for application in compositions for optical detonator capsules. © 2015, Springer Science+Business Media New York.


Kriger V.G.,Kemerovo State University | Kalenskii A.V.,Kemerovo State University | Zvekov A.A.,RAS Institute of Coal Chemistry and Chemical Materials Science | Zykov I.Y.,Kemerovo State University | Nikitin A.P.,Kemerovo State University
Thermophysics and Aeromechanics | Year: 2013

A model to describe the heating of metal inclusions in inert media by a laser radiation pulse with allowance for the heat-transfer and melting processes in the matrix and inclusion materials is proposed. The time regularities of the heating of the matrix and inclusions were examined, and the dependences of the maximum temperature on the particle surface on the laser pulse energy density and on the particle radius were obtained. Approximate formulae for the maximum heating temperature and for the radius of most heated particles are proposed. We show that melting processes result in a reduction of the maximum heating temperature and in an insignificant variation of the radius of most heated particles. © 2013 Pleiades Publishing, Ltd.


Okhlopkova L.B.,RAS Boreskov Institute of Catalysis | Kerzhentsev M.A.,RAS Boreskov Institute of Catalysis | Ismagilov Z.R.,RAS Institute of Coal Chemistry and Chemical Materials Science
Kinetics and Catalysis | Year: 2016

A continuously working capillary microreactor with a catalytic coating based on mesoporous titanium dioxide with embedded Pd nanoparticles was tested in a reaction of the selective hydrogenation of 2-methyl-3-butyn-2-ol (MBI). The catalytic coatings were obtained by the supporting of a carrier sol, which contained colloidal Pd nanoparticles, onto the internal wall of a quartz capillary with a diameter of 250 μm in the dynamic mode. The effects of the concentration of MBI in methanol (0.05–0.2 mol/L), the partial pressure of hydrogen (0.28–1.0 atm), and the reaction temperature (308–333 K) on the catalyst activity and the selectivity of reaction were studied. High selectivity for the formation of the semi-hydrogenated product 2-methyl-3-buten-2-ol was reached at 313 K in an atmosphere of pure hydrogen. At a conversion of 99.9%, the selectivity was 92.3%, which is 15.5% higher than that in a batch reactor. The rate of hydrogenation on the Pd/TiO2 coating was higher by one order of magnitude than that on a commercial Lindlar catalyst. The coating remained stable upon the continuous passage of the flow of a reaction mixture for 500 h. © 2016, Pleiades Publishing, Ltd.


Rokosov Yu.V.,RAS Institute of Coal Chemistry and Chemical Materials Science | Rokosova N.N.,RAS Institute of Coal Chemistry and Chemical Materials Science
Chemistry and Technology of Fuels and Oils | Year: 2015

We have studied the qualitative and quantitative composition of hydrocarbons formed in the hydropyrolysis of sapropelic coals. It was observed that 30-50% of pyrolytic conversions of the organic mass in the studied sapropelic coals at 420°C under hydrogen pressure are associated with the formation of liquid hydrocarbons typical of petroleum kerosene and diesel fractions. It was noted that the hydropyrolysis products contain more alkanes and fewer alkenes and cycloalkanes than the hydrogen-free pyrolysis products. Based on the composition of unbranched, isoprenoid, and cyclic pyrogenic hydrocarbon biomarkers, we draw conclusions concerning the marine origin of the original biomass in the studied coals and the pathways for the formation of hydropyrolysis products from lipid structural components. © 2015 Springer Science+Business Media New York.


Zherebtsov S.I.,RAS Institute of Coal Chemistry and Chemical Materials Science | Ismagilov Z.R.,RAS Institute of Coal Chemistry and Chemical Materials Science
Solid Fuel Chemistry | Year: 2012

The effect of alkylation with alcohols in the presence of a mineral acid on the yield of humic acids from brown coal and peat was studied. A change in the ratio between the phenol and carboxyl groups of humic acids depending on the conditions of brown coal and peat alkylation was shown. An increased biological activity of humates obtained from the alkylated materials was noted. © 2012 Allerton Press, Inc.


Al'tshuler G.N.,RAS Institute of Coal Chemistry and Chemical Materials Science
Solid Fuel Chemistry | Year: 2012

The nanoreactor synthesis of pyridinecarboxylic acids-the precursors of biologically active compounds-was performed by the catalytic oxidation of coal tar components. The composite of Pd or Pd and Ag nanoparticles on a matrix of sulfonated polycalixresorcinarene was used as a nanoreactor. It was found that nicotinic acid can be obtained by the nanoreactor oxidation of βpicoline with cerium(IV) sulfate at 1.013 10 -5 Pa and 25-30°C. © 2012. Allerton Press, Inc.

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