The study of pyrolysis process of different types of oil-containing wastes was conducted in order to evaluate the possibility of extracting liquid products. Proximate and ultimate analysis of the ...feedstock as well as its thermogravimetric study were performed. The data on the yield of pyrolysis products were obtained in the fixed bed retorting system, depending on the process temperature. The resulting products of pyrolysis of oil-containing wastes were investigated to draw up a balance of elements.
The software for determining charged track parameters of the Spin Physics Detector (SPD) experiment on the future Nuclotron based Ion Collider fAcility (NICA) collider (JINR, Dubna) is presented ...along with the results obtained. The use of this program allows prompt simulations of various magnetic field configurations and the tracking system of the SPD experiment to determine the optimal structure for better track reconstruction.
The relaxation times of localized states of antimony donors in unstrained and strained germanium uniaxially compressed along the 111 crystallographic direction are measured at cryogenic temperatures. ...The measurements are carried out in a single-wavelength pump–probe setup using radiation from the Novosibirsk free electron laser (NovoFEL). The relaxation times in unstrained crystals depend on the temperature and excitation photon energy. Measurements in strained crystals are carried out under stress bar
S
> 300, in which case the ground-state wavefunction is formed by states belonging to a single valley in the germanium conduction band. It is shown that the application of uniaxial strain leads to an increase in the relaxation time, which is explained by a decrease in the number of relaxation channels.
The relaxation times of excited states of arsenic dopant in germanium at cryogenic temperatures
T
< 15 K have been experimentally studied by the optical pump-probe method using radiation of a ...free-electron laser. Two variants of the excitation of impurity centers have been used in the experiment: (i) from the 1
s
(
A
1
) ground state of the dopant and (ii) from the 1
s
(
T
2
) first excited state having a finite thermal population. In the former variant, it has been shown that the decay times of the 2
p
0
and 3
p
±
states are about 0.8 and 0.6 ns, respectively. In the latter variant, a single measurement can simultaneously provide the relaxation times of two 2
p
±
and 1
s
(
T
2
) states about 0.6 and no more than 0.16 ns, respectively. The data obtained have indicated the possibility of forming population inversion and the gain of terahertz radiation at the 2
p
±
→ 1
s
(
T
2
) and 2p
0
→ 1
s
(
T
2
) transitions at the optical excitation of the mentioned impurity centers.
The effect of irradiation with soft X-rays produced by a laser plasma source equipped with an X-ray concentrator on the properties of the CdHgTe semiconductor are investigated. For this purpose, the ...mass concentration of atoms in the near-surface layer of the material is measured. It is demonstrated that the action of soft X-ray radiation leads to change in the solid-solution composition at the surface via a nonthermal mechanism and generates surface defects.
In magnetostrictive RFe2 (R – rare earth) materials, magnetic properties such as magnetocrystalline anisotropy and Curie temperature can have a profound impact on the magnetostriction, often reducing ...its value in practically applicable magnetic field at normal conditions. Tuning the atomic structure by Mn alloying is one of the research strategies that allows to improve both elastic and magnetoelastic properties. Here we investigate novel non-stoichiometric TbFe2Mnx (0 ≤ x ≤ 0.25) compounds in which Mn partially replaces both Tb and Fe. Curie temperature and magnetic moment values decrease with manganese alloying. We interpret these effects as a consequence of lowered Fe-Fe exchange interactions which is confirmed within two-sublattice molecular field model. Magnetocrystalline anisotropy estimated by law of approach to magnetic saturation in high pulsed magnetic fields shows trend of decrease with Mn doping. Notably, this cause significant increase of linear magnetostriction (up to 25%) for TbFe2Mnx compounds at liquid nitrogen temperature. Thermal expansion declined due to growth of magnetic contribution in magnetically ordered state, which is linked to volume magnetostriction. These changes make TbFe2Mnx promising material for practical application. Thus, it was shown that manganese alloying opens new way for tuning magnetocrystalline anisotropy and magnetostriction in non-stoichiometric Laves phase compounds.
•Magnetocrystalline anisotropy of TbFe2Mnx lowers with Mn alloying.•Thermal expansion decreases due to rise of magnetic contribution.•Curie temperature decline explained by changing exchange interactions.•Mn addition leads to growth of magnetostriction at 77 K.
We present the optical and magneto-optical spectroscopy and electron paramagnetic resonance (EPR) investigations of CaMoO4 single crystals doped with the erbium ions. Telecom-wavelength resonance ...transition inhomogeneous line width of Er3+ is relatively narrow for oxide crystals which makes this material promising for quantum technologies applications. The hyperfine structure in optical spectra of 167Er3+ isotope is well resolved. Energies and symmetries of wavefunctions of 39 energy levels of Er3+ ions in the crystal-field (CF) of S4 symmetry and g-factors of some CF Kramers doublets were measured and successfully simulated on the basis of CF calculations. The obtained set of CF parameters was used for modeling the hyperfine structure profiles observed in the optical absorption spectra.
•Optical f-f, Zeeman and EPR spectra of Er3+ in CaMoO4 are presented.•Well-resolved hyperfine structure of 167Er3+ spectral lines was registered.•Crystal field energies and g-factors are reproduced by simulations.•Substantial contributions of the forced electric dipole transitions were revealed.
At a certain form of broadband source soft X-ray spectrum is expected to achieve selective radiation exposure to one of the elements of a multi-component material CdXHg1-XTe. In this case we can talk ...about a change of the surface properties of the substance as a result of selective absorption of soft X-rays.
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