A
bstract
In this paper we revisit the idea of measuring the magnetic dipole moments of the charm baryons and, in particular, of
Λ
c
+
by studying the spin precession induced by the strong effective ...magnetic field inside the channels of a bent crystal. We present a detailed sensitivity study showing the feasibility of such an experiment at the LHC in the coming years.
The effect of high-temperature radial-shear rolling (RSR) on the strain and stress distributions in the cross-sections of processed rods has been studied using finite element method simulation for ...the industrial 7075 alloy and compared with that for the new Al7Zn2.8Mg0.7Ni0.55Fe0.2Zr alloy. The simulation has revealed a gradient strain distribution along the cross-section of the processed rods for both alloys. The lowest stress has been observed in the central part of the rods, whereas the peripheral zones have had the highest strain with a factor of more than 1.5. For both alloys, the maximum true strain localized in the peripheral zones of the rods (~10) has proven to be substantially higher than the true strain (~2.1) caused by change in the overall (linear) dimensions of the rods. The results of numerical simulation of the stress and strain distributions have been in a good agreement with the as-deformed structure. For example, we have observed the formation of a gradient structure consisting of deformed fibrous grains in the central parts of the rods (in the vicinity of their axes) whereas in the middle of rod diameter and in the surface layers that are exposed to the highest stress and strain the structure contained more equiaxed and finer grains formed during dynamic recrystallization. The results of uniaxial tensile tests have revealed that the mechanical properties of the 7075 alloy (UTS ~ 390 MPa, YS ~ 280 MPa and δ ~ 9.9%) after RSR are comparable to those of the new alloy the microstructure of which additionally contains fine intermetallic particles. Thus, radial-shear rolling can be considered as an efficient industrial technology of high-strength aluminum alloys allowing one to achieve a combination of high strength and ductility in as-processed materials with a gradient grain structure.
Despite the fact that more than 90% of tryptophan is metabolized via the kynurenine pathway, the serotonin pathway is of great importance for the functioning of the central nervous system. The main ...products of this pathway are serotonin and melatonin. They provide maintenance of the sleep–wake mode, modulation of oxidative stress activity, apoptosis of neurons and glial elements, regeneration and neuroinflammation. In the pathogenesis of Alzheimer’s disease, neuroinflammation plays one of the main roles. Melatonin and serotonin, being modulators of its intensity, as well as an important component of neurochemical interactions that provide cognitive functions, can be considered as targets for preventive and therapeutic effects.
The conditions of circumferential fracture during hot radial-shear rolling are simulated using QForm software. The fields of modified Cockroft–Latham criterion and temperature are plotted. The ...results of simulation were validated experimentally by rolling bars made of creep-resistant alloy. Controlled circumferential fracture was created by intensifying the self-heating by increasing the rolling speed. The fracture zone was examined metallographically. The experiment confirmed that the main cause of circumferential fracture of the workpiece during radial-shear rolling is the rapid self-heating in the fracture zone rather than the stress state and ductility of the material. These results were confirmed by examining the fracture zone with a microscope.
The structure and paramagnetic properties of the Dy(H
2
O)
n
(CyDTA)
–
complex are studied by
1
H NMR using the analysis of paramagnetic shifts and spin-spin relaxation rates for an
ab initio
...structural model. It is shown that significant temperature-dependent spectral line broadening is due to the Curie-spin contribution to the paramagnetic spin-spin relaxation rate enhancement. The complex demonstrates conformational, kinetic, and thermodynamic stability in the temperature range from 278 K to 368 K. The maximum temperature sensitivity of chemical shifts
d
(δ
exp
)/
dT
is equal to 0.44 ppm/K. Due to its thermodynamic and conformational stability, this compound may be prospective for the design of thermally sensitive NMR probes in aqueous media.
The work was dedicated to the laser modules for the spectral range of 975 nm based on single laser diodes with fiber output to be designed and manufactured. The installation of an optical system for ...the seven laser diodes radiation input into a silica-silica fiber with a core diameter of 105 μm and a numerical aperture of 0.15 has been carried out while investigating their power and spectral characteristics. The maximum output power of the laser module was 65 W in CW operation at a nominal current of 12 A and a thermal stabilization temperature of 25°C, the total efficiency of the laser module was 43%, and the brightness of the laser module amounted to 10.6 MW/(cm
2
sr).
Mirror matter is considered as a candidate for dark matter. In connection with this an experimental search for neutron–mirror neutron (nn′) transitions has been carried out using storage of ultracold ...neutrons in a trap with different magnetic fields. As a result, a new limit for the neutron–mirror neutron oscillation time
τ
osc has been obtained,
τ
osc≥448
s (90% C.L.), assuming that there is no mirror magnetic field larger than 100
nT. Besides a first attempt to obtain some restriction for mirror magnetic field has been done.
The possibility of creating a self-sustained regime of a running nuclear burning wave in the critical fast reactor with the mixed Th-U fuel is demonstrated. The calculations were performed in the ...deterministic approach based on solving the non-stationary multi-group diffusion equation of neutron transport together with the set of equations of the fuel component burn-up and the nuclear kinetics of precursor nuclei of delayed neutrons. The presence of the constructional material Fe and the coolant (the Pb–Bi eutectic) in the reactor composition is taken into account. The calculation results of the space-time evolution of neutron flux and fuel component concentrations are presented for different values of the Th-U ratio in the fuel. The calculations show the remarkable stability of the nuclear burning wave regime against neutron flux distortions in the reactor, which is a result of the negative feedback on reactivity inherent to this regime. This is one of the most important features of the reactor of this type, which ensures its intrinsic safety.
► Deterministic approach for nuclear burning wave (NBW) phenomenon study is developed. ► Existence of NBW regime in fast reactor (FR) with mixed Th-U fuel is proved. ► Remarkable stability of NBW regime in FR is demonstrated. ► Negative feedback on reactivity ensures intrinsic safety of FR working in NBW regime.
A 581 km vibroseis-source, deep seismic reflection survey was acquired through the Capricorn Orogen of Western Australia and, for the first time, provides an unprecedented view of the deep crustal ...architecture of the West Australian Craton. The survey has imaged three principal suture zones, as well as several other lithospheric-scale faults. The suture zones separate four seismically distinct tectonic blocks, which include the Pilbara Craton, the Bandee Seismic Province (a previously unrecognised tectonic block), the Glenburgh Terrane of the Gascoyne Province and the Narryer Terrane of the Yilgarn Craton. In the upper crust, the survey imaged numerous Proterozoic granite batholiths as well as the architecture of the Mesoproterozoic Edmund and Collier basins. These features were formed during the punctuated reworking of the craton by the reactivation of the major crustal structures. The location and setting of gold, base metal and rare earth element deposits across the orogen are closely linked to the major lithospheric-scale structures, highlighting their importance to fluid flow within mineral systems by the transport of fluid and energy direct from the mantle into the upper crust.
The air flow in the human bronchial tree is simulated in the normal and pathological cases. Analytical formulas are derived to design the full bronchial tree. All surfaces of the bronchial tree are ...matched with the second order of smoothness (there are no acute angles or ribs). The geometric characteristics of the human bronchial tree in the pathological case are modeled by a “starry” shape of the inner structure of the bronchus; the pathology degree is defined by two parameters: bronchus constriction level and degree of distortion of the cylindrical shape of the bronchus. A numerical technique is proposed for stage-by-stage computing of air motion in the human bronchial tree. A laminar air flow in the human bronchial tree is computed from the input bronchus to alveoli). It is demonstrated that the pressure decrease in the case of a laminar air flow in the bronchial tree is twice smaller than that in the turbulent case. Distortions of the cylindrical shape of the bronchi in the pathological case lead to a more significant pressure decrease in the bronchial tree.
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