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141.
In this paper, we establish the invariance of cyclic (co)homology of left Hopf algebroids under the change of Morita equivalent base algebras. The classical result on Morita invariance for cyclic homology of associative algebras appears as a special example of this theory. In our main application we consider the Morita equivalence between the algebra of complex-valued smooth functions on the classical 2-torus and the coordinate algebra of the noncommutative 2-torus with rational parameter. We then construct a Morita base change left Hopf algebroid over this noncommutative 2-torus and show that its cyclic (co)homology can be computed by means of the homology of the Lie algebroid of vector fields on the classical 2-torus. 相似文献
142.
Franco Doro Niels Akeroyd Franc Schiet Anubhav Narula 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(22):7248-7253
The Prins reaction, an acid‐catalyzed condensation of alkenes with aldehydes, is used extensively in the fragrance industry. This year we celebrate the 100th anniversary of the discovery of this reaction. In honor of this occasion we present an overview of the diverse applications of the Prins reaction in the synthesis of flavor and fragrance ingredients. To pay tribute to the inventor of the Prins reaction, Hendrik Jacobus Prins, we also provide some insight into his life, scientific, and entrepreneurial accomplishments. 相似文献
143.
Niels Asger Mortensen Kristinn Johnsen Antti-Pekka Jauho Karsten Flensberg 《Superlattices and Microstructures》1999,26(6):351
We consider the conductance of a quantum tube connected to a metallic contact. The number of angular momentum states that the tube can support depends on the strength of the radial confinement. We calculate the transmission coefficients which yield the conductance via the Landauer formula, and discuss the relation of our results to armchair carbon nanotubes embedded in a metal. For Al and Au contacts and tubes with a realistic radial confinement we find that the transmission can be close to unity corresponding to a contact resistance close to h / 2 e2per band at the Fermi level in the carbon nanotube. 相似文献
144.
We derive a probabilistic expression for the symbol of the generator of a Feller process. 相似文献
145.
J. Matzerath Niels Jörgen Traberg Arthur Wilhelmi G. Wempe Gasmotorenfabrik Deutz F. D. Harger Greiner Friedrichs Hammermann E. J. Goegg H. C. Deming E. Mauguin Otto Johannsen H. N. Gilbert G. A. Burrell E. R. Weaver J. D. Edwards R. Henr Forrières A. H. Elliot G. H. Oberfell G. Frerichs E. Mannheim F. W. Richardson A. Jaffée H. Kaesbohrer H. Droop Richmond E. Hembrough Harold Heath Gray G. Schuhmacher Jens O. Neuberg A. Jacquerod Tourpaïan Contzen G. T. Baxter H. W. Storkweather Société Roubaisienne d'Eclairage 《Analytical and bioanalytical chemistry》1919,58(2):70-78
146.
The helix-disfavoring, versus alanine, propagation values of lysine (0.8) and arginine (1.0) residues placed centrally in an (Ala)(9) unit have been measured by (13)C NMR. 相似文献
147.
Electrokinetic supercharging has been integrated in CZE for the development of a highly sensitive methodology for protein tryptic digest analysis. A careful choice of the experimental conditions led to sensitivity enhancement factors between 1000 and 10,000 whilst maintaining a satisfactory resolution. Peptides in the low nanomolar concentration range have been detected despite the use of the poorly sensitive UV absorbance detection mode. The buffer system used in this study is fully suitable for coupling CE to MS. 相似文献
148.
Niels Benedikter Vojkan Jakšić Marcello Porta Chiara Saffirio Benjamin Schlein 《纯数学与应用数学通讯》2016,69(12):2250-2303
In this paper we study the dynamics of fermionic mixed states in the mean‐field regime. We consider initial states that are close to quasi‐free states and prove that, under suitable assumptions on the initial data and on the many‐body interaction, the quantum evolution of such initial data is well approximated by a suitable quasi‐free state. In particular, we prove that the evolution of the reduced one‐particle density matrix converges, as the number of particles goes to infinity, to the solution of the time‐dependent Hartree‐Fock equation. Our result holds for all times and gives effective estimates on the rate of convergence of the many‐body dynamics towards the Hartree‐Fock evolution.© 2015 Wiley Periodicals, Inc. 相似文献
149.
We propose a scheme for tapered laser cooling of coasting ion beams in storage rings. Tapered cooling has recently been shown to be crucial for attaining crystalline ion beams. The scheme proposed here, based on a relative displacement of a co- and a counterpropagating Gaussian laser beam, gives a radial variation in the equilibrium velocities to which particles are cooled. The variation is approximately linear in a relatively large range transverse to the laser beams. Expressions for the spatially dependent equilibrium velocities and the range of the tapered cooling forces are derived. We discuss the dependence on laser beam parameters as well as the limitations of this cooling scheme. 相似文献
150.
Niels Olhoff 《International Journal of Solids and Structures》1974,10(1):93-109
The thickness function of a simply supported rectangular plate is determined such that the fundamental natural frequency of transverse vibrations attains an optimum value. The volume of the solid plate, its size, and data pertaining to its material properties, are assumed to be given.The problem consists of determining the deflection function corresponding to the optimal plate thickness function from a non-linear, fourth order partial differential eigenvalue problem, derived by variational analysis.Second and higher order normal derivatives of the deflection function are singular along the boundary of the domain. This behaviour is investigated analytically, and taken into account in a finite difference formulation of the problem, which is solved numerically by successive iterations. 相似文献