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61.
A.?JaakkolaEmail author A.?Shevchenko K.?Lindfors M.?Hautakorpi E.?Il’yashenko T. H.?Johansen M.?Kaivola 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,35(1):81-85
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 100 kHz for 87Rb atoms in the state |F=1, mF=-1〉.
The main advantages of the material are: 1) magnetic-field noise
is suppressed due to the dielectricity of the material and the absence
of electric currents, 2) trapped atoms can be addressed optically
through the transparent film, and 3) the film can be repatterned,
which enables different experiments with the same component. 相似文献
62.
Shevchenko A Carter J Fearick RW Förtsch SV Fujita H Fujita Y Kalmykov Y Lacroix D Lawrie JJ von Neumann-Cosel P Neveling R Ponomarev VY Richter A Sideras-Haddad E Smit FD Wambach J 《Physical review letters》2004,93(12):122501
Fine structure in the energy region of the isoscalar giant quadrupole resonance in nuclei is observed in high-resolution proton scattering experiments at iThemba LABS over a wide mass range. A novel method based on wavelet transforms is introduced for the extraction of scales characterizing the fine structure. A comparison with microscopic model calculations including two-particle two-hole (2p2h) degrees of freedom identifies the coupling to surface vibrations as the main source of the observed scales. A generic pattern is also found for the stochastic coupling to the background of the more complex states. 相似文献
63.
A procedure for numerical investigation of nonaxisymmetric temperature fields and the elastic stress-strain state of laminated rotational bodies of cylindrically and rectilinearly orthotropic materials under nonisothermal loading is proposed. The deformation of orthotropic materials is described by the equations of anisotropic elasticity theory. The equations of state are written in the form of Hookes law for homogeneous materials, with additional terms which take into account the thermal deformation, changes in the mechanical properties of materials in the circumferential direction, and their dependence on temperature. A semianalytic finite-element method in combination with the method of successive approximations is used. An algorithm for numerical solution of the corresponding nonlinear boundary problem is elaborated, which is realized as a package of applied FORTRAN programs. Some numerical results are presented.Translated from Mekhanika Kompozitnykh Materialov, Vol. 40, No. 6, pp. 731–752, November–December, 2004. 相似文献
64.
65.
V. V. Shevchenko A. V. Stryutskii N. S. Klimenko 《Theoretical and Experimental Chemistry》2011,47(2):67-92
Approaches to the production of polymeric organic–inorganic hybrid proton-exchange membranes for fuel cells by the sol–gel
method are summarized, and a classification is proposed for them. Features of the mechanism of conduction in the proton-conducting
membranes are considered. Characteristics of the hybrid membranes and of fuel cells using them are presented. The main directions
of research in this field are discussed. 相似文献
66.
E. P. Levanova T. I. Vakulskaya S. G. Shevchenko V. A. Grabelnykh E. N. Sukhomazova A. I. Albanov N. V. Russavskaya N. A. Korchevin 《Chemistry of Heterocyclic Compounds》2008,44(11):1413-1415
1,2-Ditellurolane is an extremely unstable heterocyclic compound which can be maintained in solution in the presence of nitrosodurene
for several days. It is proposed on the basis of UV spectroscopy and 1H NMR spectroscopy that a complex is formed which determines the stability of 1,2-ditellurolane. It is shown that stabilized
1,2-ditellurolane can be used in organic synthesis.
Presented to Academician of the Russian Academy of Sciences Boris Aleksandrovich Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, 1736–1738, November, 2008. 相似文献
67.
V. V. Shevchenko M. A. Gumennaya A. V. Shevchuk Yu. P. Gomza N. S. Klimenko V. V. Boichuk 《Polymer Science Series B》2009,51(1-2):46-54
The interaction of oligomeric silsesquioxanes, whose organic moieties contain tertiary amino groups and primary and secondary hydroxyl groups, with monoisocyanates and phthalic and acetic anhydrides is employed to synthesize a number of their N-alkyl(aryl)urethane-, carboxyl- and acetyl-terminated derivatives with different degrees of substitution and combinations of the substituents. The obtained derivatives are studied by functional analysis, IR spectroscopy, GPC, DSC, TGA, and wide-angle X-ray scattering. The chemical nature of the incorporated functional groups is found to markedly influence the structure and properties of the synthesized compounds. Depending on the type of substituents and their combination, either the complete amorphization or ordering of the structure of the oligosilsesquioxanes is observed with corresponding changes in their properties. 相似文献
68.
69.
70.
The projective group is represented as a bundle of centroprojective frames. This bundle is endowed with a centroprojective connection and becomes the space of this centroprojective connection. Structure equations of this space are found, which include the affine torsion tensor and the centroprojective curvature tensor containing the affine curvature subtensor. A distribution of planes in projective space and its associated principal bundle (which has two simplest and two simple (in the sense of [1]) quotient principal bundles) are considered. On the associated bundle, a group connection is defined. The object of the centroprojective connection is reduced to the object of the group connection. The object of the group connection contains the objects of the flat and normal linear connections, the centroprojective subconnection, and the affine-group connection as subobjects. The torsion object of the affine-group connection is determined. It is proved that it forms a tensor, which contains the torsion tensor of the normal linear connection as a subtensor. It is shown that the affine torsion tensor of the centroprojective connection reduces to the torsion tensor of the affine-group connection. 相似文献