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The concentrations of polycyclic aromatic hydrocarbons (PAHs), their sources and toxic equivalent (TEQ) in soil, suspended matter and bottom sediments in the Fatala River Basin ecosystem were obtained for the first time to our knowledge. Determination of 14 PAHs (ΣPAHs) was carried out using high-performance liquid chromatography. The ΣPAH content in soil ranged from 13 to 50,920 (Me = 820) ng/g. The composition of PAHs (high proportion of low-molecular-weight compounds and values of individual PAHs ratios) reflected the significant oil pollution of soil. Contaminated soil was localated in the central part of the Fatala River Basin. The median benzo(a)pyrene toxic equivalent of soil at the study site was 1.08 (range, 0.05 to 53.16) ngTEQ/g, showing generally low soil toxicity. The ΣPAH content in suspended matter was in the range of 33 to 1316 (Me = 309) ng/L. The ΣPAH content in bottom sediments ranged from 36 to 6943 (Me = 478) ng/L, corresponding to clean and moderately contaminated sediments. The ΣPAH content in bottom sediments depended on the anthropogenic impact on the Fatala River Basin territory and the bottom sediment features. Bottom sediments and suspended matter had a low toxic equivalent. [ABSTRACT FROM AUTHOR]

We review the properties of the strongly interacting quark‐gluon plasma (QGP) at finite temperature T and baryon chemical potential μB as created in heavy‐ion collisions at ultrarelativistic energies. The description of the strongly interacting (non‐perturbative) QGP in equilibrium is based on the effective propagators and couplings from the Dynamical QuasiParticle Model (DQPM) that is matched to reproduce the equation‐of‐state of the partonic system above the deconfinement temperature TC from lattice QCD. Based on a microscopic transport description of heavy‐ion collisions, we discuss which observables are sensitive to the QGP creation and its properties. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Various internal elements in large fluidized bed reactor are considered. • The analysis of the impact of various design elements is carried out. • The influence of catalyst feeder design on reactor heating is educed. • The influence of catalyst fractional composition is studied. Abstract A numerical study of the fluidized bed industrial reactor in the presence of various internal elements is carried out by CFD methods A simple reactor heating efficiency function of chemical reaction with heat absorption is considered. The main emphasis is placed on the circulation flows of the catalyst particles and heating of the reactor. The analysis of the impact of various design elements on the heating efficiency of the reactor is carried out. Particular attention is paid to the possibility of baffles applying, which allows redirecting the flow. This effect may have an especially important value when the rapid heating of the reactor is required for temperature dependent reactions. The influence of heated catalyst feeder design on the efficiency of whole reactor heating is educed. The influence of the fractional composition of the catalyst, namely the presence of fine particles, on the reactor heating efficiency for different reactor design features is also studied. The results are carried out for a specific reactor example, but contribute to the overall branch of fluidized bed engineering. [ABSTRACT FROM AUTHOR]

This paper presents the results of theoretical and experimental studies to determine the optimal thickness of thermal insulation from basalt fiber and aerogel products for pipelines at temperatures of 300 and 600 °C. We carried out a comparison of the key thermophysical characteristics of the claimed heat-insulating materials. We performed a thermal imaging survey of the furnace chimney, insulated with basalt fiber and aerogel, while controlling the temperature of the flue gases by establishing the required ratio of the flow rate of natural gas and oxidizer. The temperature gradient along the thickness of the thermal insulation was obtained using a numerical tool developed in ANSYS. The results show that aerogel surpasses basalt fiber in all key thermophysical characteristics. At the same time, the only barrier to widespread industrial production and use of aerogel in the high-temperature thermal insulation segment is its market cost, which is still several times higher than that of basalt fiber in terms of an equivalent performance. [ABSTRACT FROM AUTHOR]

We extend the parton-hadron string dynamics (PHSD) transport approach in the partonic sector by explicitly calculating the total and differential partonic scattering cross sections as a function of temperature T and baryon chemical potential μB on the basis of the effective propagators and couplings from the dynamical quasiparticle model (DQPM) that is matched to reproduce the equation of state of the partonic system above the deconfinement temperature Tc from lattice QCD. We calculate the collisional widths for the partonic degrees of freedom at finite T and μB in the timelike sector and conclude that the quasiparticle limit holds sufficiently well. Furthermore, the ratio of shear viscosity η over entropy density s, i.e., η/s, is evaluated using the collisional widths and compared to lattice QCD calculations for μB=0 as well. We find that the novel ratio η/s does not differ very much from that calculated within the original DQPM on the basis of the Kubo formalism. Furthermore, there is only a very modest change of η/s with the baryon chemical μB as a function of the scaled temperature T/Tc(μB). This also holds for a variety of hadronic observables from central A+A collisions in the energy range 5 GeV ≤√sNN≤200 GeV when implementing the differential cross sections into the PHSD approach. We only observe small differences in the antibaryon sector (p,Λ+Σ0) at √sNN=17.3GeV and 200 GeV with practically no sensitivity of rapidity and pT distributions to the μB dependence of the partonic cross sections. Small variations in the strangeness sector are obtained in all collisional systems studied (A+A and C + Au); however, it will be very hard to extract a robust signal experimentally. Since we find only small traces of a μB dependence in heavy-ion observables--although the effective partonic masses and widths as well as their partonic cross sections clearly depend on μB--this implies that one needs a sizable partonic density and large space-time QGP volume to explore the dynamics in the partonic phase. These conditions are only fulfilled at high bombarding energies where μB is, however, rather low. On the other hand, when decreasing the bombarding energy and thus increasing μB, the hadronic phase becomes dominant and accordingly it will be difficult to extract signals from the partonic dynamics based on "bulk" observables. [ABSTRACT FROM AUTHOR]

The utilization of solid waste in useful product is becoming a great deal of worth for individuals, organizations, and countries themselves. The powder of waste glass and silica fumes are also considered major waste materials across the globe. In this paper, the physico-chemical, thermal, and morphological properties of both waste powders are investigated in order to determine their suitability for use as a partial replacement for cement in basic concrete. They are suitable for use in concrete due to their pozzolanic and other basic properties. Extensive testing, in terms of the compressive strength test, the slump test, and the flexural strength test, has been carried out to study the replacement of cement in the range of 5–15% by waste glass powder for curing ages of 7 and 28 days. The FTIR analyses of both materials are studied for determining the effect of characteristics of chemical bonding and intense bands with bending vibrations of O–Si–O bonds. Experimental results indicate towards the potential utilization of wastes in concrete in terms of green concrete. [ABSTRACT FROM AUTHOR]

We extend the parton‐hadron‐string dynamics (PHSD) transport approach in the partonic sector by explicitly calculating the total and differential partonic scattering cross sections as a function of temperature T and baryon chemical potential μB on the basis of the effective propagators and couplings from the dynamical quasiparticle model (DQPM) that is matched to reproduce the equation of state of the partonic system above the deconfinement temperature Tc from lattice quantum chromodynamics (QCD). We calculate the collisional widths for the partonic degrees of freedom at finite T and μB in the time‐like sector and conclude that the quasiparticle limit holds sufficiently well. Furthermore, the ratio of shear viscosity η over entropy density s, that is, η/s, is evaluated using the collisional widths and compared to lattice QCD(lQCD) calculations for μB = 0 as well. We find that the ratio η/s does not differ very much from that calculated within the original DQPM on the basis of the Kubo formalism. Furthermore, there is only a very modest change of η/s with the baryon chemical μB as a function of the scaled temperature T/Tc(μB). This also holds for a variety of hadronic observables from central A + A collisions in the energy range 5 GeV ≤sNN≤ 200 GeV when implementing the differential cross sections into the PHSD approach. Accordingly, it will be difficult to extract finite μB signals from the partonic dynamics based on "bulk" observables. [ABSTRACT FROM AUTHOR]