An approach to calculating multipole approximations of the gravitational potential of small celestial bodies with an irregular mass distribution is demonstrated for the asteroid (16) Psyche as an ...example.
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•Water disinfection by simultaneous treatment with hydrodynamic cavitation and plasma discharge.•Decomposition of organic pollutants in water under hydrodynamic cavitation and ...plasma.•Easily scalable hybrid technology combining cavitation and plasma.•Intense generation of radicals, UV light, shock waves and charged particles.•Prolonged oxidation takes place in the solution/suspension after the end of the treatment.
Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.
Hyperon II: Properties of excited hyperons Sarantsev, A. V.; Matveev, M.; Nikonov, V. A. ...
The European physical journal. A, Hadrons and nuclei,
10/2019, Letnik:
55, Številka:
10
Journal Article
Recenzirano
Odprti dostop
.
We report properties of
Λ
and
Σ
hyperon resonances formed in
K
-
induced reactions. Special emphasis is laid on the analysis of the three-body final states
2
π
0
Λ
and
2
π
0
Σ
and of the ...quasi-two-body final states
π
Λ
(
1520
)
,
K
¯
Δ
(
1232
)
,
π
Σ
(
1385
)
,
K
¯
*
N
, and
ω
Λ
. We give pole positions of
Λ
and
Σ
hyperon resonances and transition residues from the
K
-
p
initial to various final states as well as Breit-Wigner masses and widths and decay branching ratios. Twenty resonances and “bumps” reported in the Review of Particle Physics are not required in our fits, evidence for five new resonances is reported. The observed mass spectrum is compared to the spectrum calculated in the Bonn quark model. Three spin doublets, six
Λ
hyperons, are tentatively assigned to the
SU
(3) singlet system.
Solid oxide fuel cells (SOFC) are promising, environmentally friendly energy sources. Many works are devoted to the study of materials, individual aspects of SOFC operation, and the development of ...devices based on them. However, there is no work covering the entire spectrum of SOFC concepts and designs. In the present review, an attempt is made to collect and structure all types of SOFC that exist today. Structural features of each type of SOFC have been described, and their advantages and disadvantages have been identified. A comparison of the designs showed that among the well-studied dual-chamber SOFC with oxygen-ion conducting electrolyte, the anode-supported design is the most suitable for operation at temperatures below 800 °C. Other SOFC types that are promising for low-temperature operation are SOFC with proton-conducting electrolyte and electrolyte-free fuel cells. However, these recently developed technologies are still far from commercialization and require further research and development.
The problem of the motion of a heavy point along an inclined plane that rotates uniformly around the vertical is considered. The area filled with non-isolated relative equilibria is determined, its ...dependence on the parameters of the problem – the angular velocity, the angle of inclination of the plane and the angle of friction – is studied. The stability of the studied relative equilibria is discussed.
The inertial characteristics of celestial bodies can be calculated using their triangle partitions based on photometric observations. Such partitions can be refined along with the accumulation of ...necessary information. In this regard, the question arises to what extent the approximations of the inertial characteristics of celestial bodies, in particular, the approximations of the components of the Euler–Poinsot tensor of different orders, are susceptible to the choice of such partitions. Such components enter into the expansion of the gravitational potential in harmonic polynomials. In this paper, for some small celestial bodies, a comparison of such coefficients is carried out as coarse partitions are replaced with finer ones.
For asteroid (433) Eros, a multipole representation of the gravitational potential is determined up to multipoles of the fourth order. The obtained expression for the potential is used in ...constructing the areas of possible motion of the spacecraft in the vicinity of the celestial body under consideration.
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The problem of motion of a point particle on the surface of a homogeneous gravitating ball with a spherical cavity is considered. It is assumed that the body rotates uniformly around its axis of ...symmetry. At the same time, it is assumed that a particle located on the outer or inner (inside the cavity) surface of the body, in addition to the force of gravity, is affected by dry friction. The gravitational properties inside the cavity and outside the ball are described. The dependence of the existence, bifurcations, and stability of the relative equilibria of a point particle on the outer or inner body surface on the parameters of the problem is studied. The results obtained both analytically and numerically are presented in the form of bifurcation diagrams. The research is motivated by the possible existence of cavities or mass concentrations (mascons) in large and small celestial bodies.
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