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71.
We prove that there is a Poincaré type duality in E-theory between higher rank graph algebras associated with a higher rank graph and its opposite correspondent. We obtain an
r-duality, that is the fundamental classes are in Er. The basic tools are a higher rank Fock space and higher rank Toeplitz algebra which has a more interesting ideal structure
than in the rank 1 case. The K-homology fundamental class is given by an r-fold exact sequence whereas the K-theory fundamental class is given by a homomorphism. The E-theoretic products are essentially pull-backs so that the computation is done at the level of exact sequences.
Mathematics Subject Classification (2000): 46L80. 相似文献
72.
73.
T. Badica S. Dima A. Gelberg I. Popescu 《Zeitschrift für Physik A Hadrons and Nuclei》1972,249(4):321-326
Angular correlation measurements of the γ transitions coincident with 35.5 keV in125Te were carried out with Ge(Li)-Si(Li) detectors. Mixing ratios for some of the transitions were determined. 相似文献
74.
E. Drǎgulescu M. Ivaşcu R. Mihu D. Popescu G. Semenescu V. Paar D. Vretenar 《Nuclear Physics A》1984,419(1):148-162
The low-lying states of 143Nd and 154Nd have been studied by means of Coulomb excitation with 16O and α-particles. Angular distribution measurements were carried out for some transitions in 145Nd with 11.2 MeV α-particles. Level energy decay schemes and B(E2)↑ values were measured for two states in 143Nd and for six states in 145Nd. Some spin assignments have been established for the 145Nd nucleus. 143Nd and 145Nd have been theoretically described by coupling one and three particles, respectively, to quadrupole vibrations, and rather good agreement with experiment was achieved. 相似文献
75.
76.
77.
The paper considers the injection of minority carriers into a relaxation semiconductor under uniform illumination. Steady state solutions have been computed, and used to assess the nature of the recovery process after cessation of the light. It is concluded that measurements of photoconductive decay do not in general lead to reliable lifetime estimates because, besides recombination, the movement of space charges is involved in the recovery. 相似文献
78.
Liviu Horia Popescu 《Journal of Differential Equations》2004,203(1):28-37
In the present work, we give necessary and sufficient conditions for linear differential non-autonomous equations on a Banach space, that satisfy exponential dichotomy, to be topologically equivalent. We shall also prove that such equations are structurally stable. 相似文献
79.
T. Bădică C. Ciortea S. Dima A. Petrovici I. Popescu 《Zeitschrift für Physik A Hadrons and Nuclei》1978,284(2):161-163
The properties of some high excited states of171Tm have been studied using Ge(Li) detectors. The directional angular correlation measurements for 277.4-210.5 keV cascade are in agreement with the spins of the 635.4 keV© and 912.8 keV(5/2) levels. The magnetic momentμ=(1.15±0.21)μ N of the 635.4 keV level was determined by integral perturbed angular correlation (IPAC) in external magnetic field. 相似文献
80.