100 research outputs found
Experience in feeding coal into a liquefaction process development unit
A system for preparing coal slurry and feeding it into a high pressure liquefaction plant is described. The system was developed to provide supporting research and development for the Bureau of Mines coal liquefaction pilot plant. Operating experiences are included
: Implications of the rhombohedral k-space texture on the evaluation of the in-plane/out-of-plane conductivity anisotropy
Different computational scheme for calculating surface integrals in
anisotropic Brillouin zones are compared. The example of the transport
distribution function (plasma frequency) of the thermoelectric Material \BiTe
near the band edges will be discussed. The layered structure of the material
together with the rhombohedral symmetry causes a strong anisotropy of the
transport distribution function for the directions in the basal (in-plane) and
perpendicular to the basal plane (out-of-plane). It is shown that a thorough
reciprocal space integration is necessary to reproduce the
in-plane/out-of-plane anisotropy. A quantitative comparison can be made at the
band edges, where the transport anisotropy is given in terms of the anisotropic
mass tensor.Comment: 7 pages, 6 figs., subm. to J. Phys. Cond. Ma
Implementation of a non-equilibrium Green's function method to calculate spin transfer torque
We present an implementation of the steady state Keldysh approach in a
Green's function multiple scattering scheme to calculate the non-equilibrium
spin density. This density is used to obtain the spin transfer torque in
junctions showing the magnetoresistance effect. We use our implementation to
study the spin transfer torque in metallic Co/Cu/Co junctions.Comment: 4 pages, 4 figure
Antimicrobial Resistance: A Risk Factor for the Biosafety System
Scientific relevance. In recent years, antimicrobial resistance in pathogenic microorganisms has become a global problem that threatens the health of humans and animals and poses a risk to the biosafety of Russia.Aim. The study aimed to analyse the prevalence of antimicrobial resistance, consider the risks and medical consequences of this biological phenomenon, and suggest ways to optimise the use of existing antimicrobial agents and search for new ones.Discussion. The emergence of antibiotic resistance in bacteria is a natural biological process; the selection of resistant microorganisms occurs constantly with the use of the entire spectrum of antimicrobial agents in healthcare, agriculture, and other fields. The World Health Organisation (WHO) monitors these processes using the Global Antimicrobial Resistance Surveillance System (GLASS). Russia has adopted the Strategy to prevent the spread of antimicrobial resistance in the Russian Federation to 2030. The country has established a regulatory framework that supports the operation of the national antimicrobial resistance prevention system. The strategy to prevent the spread of antimicrobial resistance is being implemented through making organisational arrangements and developing novel medicines with mechanisms of action based on an understanding of the molecular mechanisms of infection and resistance. This review considers the main approaches to designing exploratory studies and evaluating the antimicrobial activity of the innovative molecules obtained. The rapid development of synthetic biology increases the likelihood of creating synthetic biological pathogens with high virulence and resistance to antimicrobial agents, which might pose risks of artificial epidemics.Conclusions. The antimicrobial resistance prevention system in Russia should be considered a strategically essential medical technology ensuring the biosafety of the country and the people
Lorenz function of BiTe/SbTe superlattices
Combining first principles density functional theory and semi-classical
Boltzmann transport, the anisotropic Lorenz function was studied for
thermoelectric BiTe/SbTe superlattices and their bulk
constituents. It was found that already for the bulk materials BiTe
and SbTe, the Lorenz function is not a pellucid function on charge
carrier concentration and temperature. For electron-doped
BiTe/SbTe superlattices large oscillatory deviations
for the Lorenz function from the metallic limit were found even at high charge
carrier concentrations. The latter can be referred to quantum well effects,
which occur at distinct superlattice periods
Thermoelectric transport in superlattices
The thermoelectric transport properties of
superlattices are analyzed on
the basis of first-principles calculations and semi-classical Boltzmann theory.
The anisotropy of the thermoelectric transport under electron and hole-doping
was studied in detail for different superlattice periods at changing
temperature and charge carrier concentrations. A clear preference for
thermoelectric transport under hole-doping, as well as for the in-plane
transport direction was found for all superlattice periods. At hole-doping the
electrical transport anisotropies remain bulk-like for all investigated
systems, while under electron-doping quantum confinement leads to strong
suppression of the cross-plane thermoelectric transport at several superlattice
periods. In addition, insights on the Lorenz function, the electronic
contribution to the thermal conductivity and the resulting figure of merit are
given
Development of a prototype multichannel communications network maintenance expert system.
http://archive.org/details/developmentofpro00yavoNAN
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