24 research outputs found
Steady state bifurcations for the Kuramoto-Sivashinsky equation: A computer assisted proof
Reconfigurable atom chip on a transparent ferrite-garnet film
We introduce a new choice of material for the creation of microscopic
magnetic
potentials for the trapping and guiding of ultracold neutral atoms.
The potentials are created above a ferrimagnetic, transparent (BiYTmGd)3(FeGa)5O12
film by patterning the magnetic-domain structure in the film with
a magneto-optical recording method. Patterns with linewidth down to
2 μm have been achieved, enabling trap frequencies of the order
of 100Â kHz for 87Rb atoms in the state .
The main advantages of the material are: 1)Â magnetic-field noise
is suppressed due to the dielectricity of the material and the absence
of electric currents, 2)Â trapped atoms can be addressed optically
through the transparent film, and 3)Â the film can be repatterned,
which enables different experiments with the same component
Attractors of Navier-Stokes systems and of parabolic equations, and estimates for their dimensions
Calculating neutron-flux functionals by the Monte Carlo method in breeder systems with leakage specified by a geometric parameter
Algebraically and analytically solvable local problems in the theory of ordinary differential equations
Structure and Properties of Nano- and Microcomposite Coating Based on Ti-Si-N/WC-Co-Cr
Using the two technologies: plasma-detonation and vacuum-arc deposition, we fabricated two types of coatings: Ti-Si-N/WC-Co-Cr/steel and Ti-Si-N/steel. We found that the top coating of Ti-Si-N was nanostructured one with 12 to 15 nm grain sizes and H = 40 to 38 GPa hardness. A thick coating which was deposited using the pulsed plasma jet, demonstrated 11 to 15.3 GPa hardness, an elastic modulus (E) changing within 176 to 240 GPa, and tungsten carbide grain dimensions varying from 150 to 350 nm to several microns. An X-ray diffraction analysis shows that the coating has the following phase composition: TiN, (Ti,Si)N solid solution, WC, tungsten carbides. An element analysis was performed using energy dispersive spectroscopy (microanalysis) and scanning electron microscopy, as well as the Rutherford backscattering of ion and the Auger electron spectroscopy. Surface morphology and structure were analyzed using scanning electron microscopy and scanning tunnel microscopy. Tests friction and resistance (cylinder-plane) demonstrated essential resistance to abrasive wear and corrosion in the solution. The decrease of grain dimensions ≤ 10 nm occurring in the top Ti-Si-N coating layer increased the sample hardness to 42 ± 2.7 GPa under at.% concentration