743 research outputs found
Strategic directions of transport and logistics to ensure the implementation of new industrialization processes
Ensuring the processes of industrialization of the modern economy requires the formation of an efficient transport and logistics infrastructure. The solution of this task is carried out using the tools of strategic management, in particular the formation of strategic goals. The article presents the strategic goals and the corresponding strategic measures in the field of ensuring the availability and quality of transport and logistics services in the field of freight traffic at the level of the needs of the development of the economy of the Sverdlovsk region. © Published under licence by IOP Publishing Ltd
Infrared spectra of some sulfides and their analogs of binary composition in the long-wave region
The far infrared spectra (500-60/cm) of some simple sulfides and their analogs were studied. In all, 22 minerals with different structure types were investigated, out of which 14 are sulfides (galena, alabandite, pyrrhotite, sphalerite, wurtzite, cinnabar, realgar, orpiment, getchelite antimonite, molybdenite, pyrite, marcasite and heazlewoodite) 6 arsenides (niccolite, domeykite, arsenopyrite, lollingite, rammelsbergite and skutterudite), one telluride (tetradymite) and native arsenic. The main bands of infrared absorption spectra of the minerals are compared with the relative strength of the interatomic bonds and their interpretation is given
Modification of magnetic and transport properties of manganite layers in Au/La_0.67Sr_0.33MnO_3/SrTiO_3 interfaces
The effect of gold capping on magnetic and transport properties of optimally
doped manganite thin films is studied. An extraordinary suppression of
conductivity and magnetic properties occurs in epitaxial (001)
La_0.67Sr_0.33MnO_3 (LSMO) films grown on SrTiO_3 upon deposition of 2 nm of
Au: in the case of ultrathin films of LSMO (4 nm thick) the resistivity
increases by four orders of magnitude while the Curie temperature decreases by
180 K. Zero-field 55Mn nuclear magnetic resonance reveals a significant
reduction of ferromagnetic double-exchange mechanism in manganite films upon
the gold capping. We find evidence for the formation of a 1.9-nm thick magnetic
"dead-layer" at the Au/LSMO interface, associated with the creation of
interfacial non double-exchange insulating phases.Comment: 4 figure
55Mn NMR and magnetization studies of La0.67Sr0.33MnO3 thin films
55Mn nuclear magnetic resonance and magnetization studies of the series of
La0.67Sr0.33MnO3 thin films have been performed at low temperature. Two
distinct lines were observed, at 322 MHz and 380 MHz, corresponding to two
different phases, the former located at the interface, with localized charges,
and the latter corresponding to the film bulk, with itinerant carriers (as it
was also found in Ca manganite films). The spin-echo amplitude was measured as
a function of a dc magnetic field applied either in the film plane or
perpendicular to it. The field dependence of both the main NMR signal intensity
and frequency shift is quite consistent with that calculated in a simple single
domain model. The best fit to the model shows that magnetization rotation
processes play a dominant role when the applied field exceeds the effective
anisotropy field. Distinctly different magnetic anisotropies are deduced from
the interface NMR signal.Comment: 7 pages, 8 figure
Kondo Insulator to Semimetal Transformation Tuned by Spin-Orbit Coupling
Recent theoretical studies of topologically nontrivial electronic states in
Kondo insulators have pointed to the importance of spin-orbit coupling (SOC)
for stabilizing these states. However, systematic experimental studies that
tune the SOC parameter in Kondo insulators remain elusive.
The main reason is that variations of (chemical) pressure or doping strongly
influence the Kondo coupling and the chemical potential --
both essential parameters determining the ground state of the material -- and
thus possible tuning effects have remained unnoticed. Here
we present the successful growth of the substitution series
CeBi(PtPd) () of the archetypal
(noncentrosymmetric) Kondo insulator CeBiPt. The Pt-Pd substitution
is isostructural, isoelectronic, and isosize, and therefore likely to leave
and essentially unchanged. By contrast, the large mass
difference between the element Pt and the element Pd leads to a large
difference in , which thus is the dominating tuning
parameter in the series. Surprisingly, with increasing (decreasing
), we observe a Kondo insulator to semimetal transition,
demonstrating an unprecedented drastic influence of the SOC. The fully
substituted end compound CeBiPd shows thermodynamic signatures of a
recently predicted Weyl-Kondo semimetal.Comment: 6 pages, 5 figures plus Supplemental Materia
- …