Using self-assembly of polystyrene spheres, well-ordered templates have been prepared on glass and silicon substrates. Strong guiding of self-assembly is obtained on photolithographically structured ...silicon substrates. Magnetic antidot arrays with three-dimensional architecture have been prepared by electrodeposition in the pores of these templates. The shape anisotropy demonstrates a crucial impact on magnetization reversal processes.
Status of the BAIKAL neutrino experiment Avrorin, A. V.; Aynutdinov, V. M.; Balkanov, V. A. ...
Bulletin of the Russian Academy of Sciences. Physics,
03/2011, Letnik:
75, Številka:
3
Journal Article
Recenzirano
The development of the NT1000 km
3
neutrino telescope at Lake Baikal has been the main goal of the BAIKAL collaboration since 2006. This work presents selected results obtained in the course of ...developing and testing key elements and systems of the future detector.
The problem of echo effects that can originate in graphene and bilayer graphene upon the generation of relativistic Landau levels in a quantizing magnetic field is considered. Graphene (bilayer ...graphene) is considered in a long-wave approximation near the Dirac points. It is proposed that the echo effect be used for the quantum memory of optical states in the far infrared.
The total impedance tensor in a 120
μm-diameter (Co
0.95Fe
0.05)
72.5Si
12.5B
15 amorphous wire subjected to annealing under torsion stress has been measured as a function of a DC axial field
H
ex ...with the DC bias current
I as a parameter. Helical magnetic anisotropy has been induced by heat treatment under torsional stress. The modification to the impedance-field characteristics caused by a DC bias current has been investigated in conjunction with the static magnetisation processes. The combination of the helical anisotropy and the DC bias field induced by a current
I results in asymmetry in the static magnetic configuration. The modifications in the impedance plots due to
I are of the same kind as those for the DC magnetisation loops: with increasing
I the hysteresis loop becomes narrower and asymmetrical. This shows clearly that the asymmetry in the impedance-field (MI) behaviour is related to the static magnetic structure that originates from a combination of the helical anisotropy and DC circumferential field. Introducing asymmetry enhances the MI sensitivity and is also important to realise linear sensing.
Terahertz emission spectra in a longitudinal electric field and lateral photoconductivity spectra under terahertz illumination have been studied in structures with GaAs/AlGaAs quantum wells (QWs). It ...is shown that the spectra contain features associated with electron transitions involving resonant impurity states related to the second quantum-well subband. Calculations of the energy spectrum of impurity states and matrix elements of optical transitions made by taking into account various positions of the impurity relative to the QW center confirm the assumptions made.
•The heat transfer coefficient increases many times upon boiling on a capillary-porous coating.•Heat transfer on a cоating is lower than on a smooth surface during evaporation.•Pressure determines ...the mechanism of crises during evaporation and boiling on a coating.•The CHF increases significantly on the microstructured surface produced by a 3D laser printer.
Heat transfer was experimentally studied under evaporation/boiling conditions in thin horizontal layers of n-dodecane at low relative pressures. A capillary-porous coating from a stainless steel powder with a sinusoidal 2D modulated profile was applied using a 3D laser printer. The selective laser sintering (SLS) additive technique was applied in the study. The dependence of a heat transfer coefficient on the heat flux under different pressures was studied for liquid layers various heights. The resulting experimental data were compared with the values obtained during evaporation/boiling on a smooth surface under the same conditions. A rise in the relative pressure results in an increase of the heat transfer coefficient at bubble boiling. The study demonstrates that the use of a capillary-porous coating leads to a 3.5-fold increase of the heat transfer coefficient in the regimes of bubble boiling. The heat transfer coefficient on the capillary-porous coating was lower compared to a smooth surface in heat transfer regimes with evaporation at low relative pressures. The critical heat fluxes (CHF) on the capillary-porous coating increase with the increasing height of the liquid layer.
Stanley's symmetrized chromatic polynomial is a generalization of the ordinary chromatic polynomial to a graph invariant with values in a ring of polynomials in infinitely many variables. The ...ordinary chromatic polynomial is a specialization of Stanley's one.
To each orientable embedded graph with a single vertex, a simple graph is associated, which is called the intersection graph of the embedded graph. As a result, we can define Stanley's symmetrized chromatic polynomial for any orientable embedded graph with a single vertex. Our goal is to extend Stanley's chromatic polynomial to embedded graphs with arbitrary number of vertices, and not necessarily orientable. In contrast to well-known extensions of, say, the Tutte polynomial from abstract to embedded graphs 4, our extension is based not on the structure of the underlying abstract graph and the additional information about the embedding. Instead, we consider the binary delta-matroid associated to an embedded graph and define the extended Stanley chromatic polynomial as an invariant of binary delta-matroids. We show that, similarly to Stanley's symmetrized chromatic polynomial of graphs, which satisfies 4-term relations for simple graphs, the polynomial that we introduce satisfies the 4-term relations for binary delta-matroids 7.
For graphs, Stanley's chromatic function produces a knot invariant by means of the correspondence between simple graphs and knots. Analogously we may interpret the suggested extension as an invariant of links, using the correspondence between binary delta-matroids and links.
Under the industrial operating conditions of a direct-current arc furnace in a temperature range of 1530–1650°C, the kinetics of cobalt decarburization by CoO additives is investigated. It is shown ...that, when the carbon concentration in the melt is lowered to 0.3–0.5%, the process rate is limited by the diffusion of carbon into the bulk of the liquid metal with activation energy of 58.74 kJ/mol. In the initial period of the process, the controlling stages are the saturation of the surface layer with oxygen and dissolution of CoO. To decrease the diffusion obstacles and shorten the duration of the final treatment of fire cobalt, it is recommended that convective flows in a bath be developed due to the increase in the current load.
Variational quantum algorithms are a promising tool for solving partial differential equations. The standard approach for its numerical solution are finite difference schemes, which can be reduced to ...the linear algebra problem. We consider three approaches to solve the heat equation on a quantum computer. Using the direct variational method we minimize the expectation value of a Hamiltonian with its ground state being the solution of the problem under study. Typically, an exponential number of Pauli products in the Hamiltonian decomposition does not allow for the quantum speed up to be achieved. The Hadamard test based approach solves this problem, however, the performed simulations do not evidently prove that the ansatz circuit has a polynomial depth with respect to the number of qubits. The ansatz tree approach exploits an explicit form of the matrix what makes it possible to achieve an advantage over classical algorithms. In our numerical simulations with up to \(n=11\) qubits, this method reveals the exponential speed up.
For laboratory tests of the operating cycle of the star sensors of orientation, dynamic stands are designed, which include simulators of the starry sky. Recently, to obtain an image of the starry ...sky, raster screens (computer or television) are most often used. However, the images of stars on such screens have significant differences from the real starry sky, which must be taken into account when carrying out dynamic tests of star sensors and processing their results.
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