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91.
92.
José A. de la Peña 《Algebras and Representation Theory》2014,17(3):905-930
Let A be a finite dimensional algebra over an algebraically closed field k. Assume A is basic connected with n pairwise non-isomorphic simple modules. We consider the Coxeter transformation ? A as the automorphism of the Grothendieck group K 0(A) induced by the Auslander-Reiten translation τ in the derived category Der(modA) of the module category modA of finite dimensional left A-modules. We say that A is an algebra of cyclotomic type if the characteristic polynomial χ A of ? A is a product of cyclotomic polynomials. There are many examples of algebras of cyclotomic type in the representaton theory literature: hereditary algebras of Dynkin and extended Dynkin types, canonical algebras, some supercanonical and extended canonical algebras. Among other results, we show that: (a) algebras satisfying the fractional Calabi-Yau property have periodic Coxeter transformation and are, therefore, of cyclotomic type, and (b) algebras whose homological form h A is non-negative are of cyclotomic type. For an algebra A of cyclotomic type we describe the shape of the Auslander-Reiten components of Der(modA). 相似文献
93.
Albert Compta Josep Ferrer Marta Peña 《Mathematical Methods in the Applied Sciences》2011,34(3):309-314
Given ?? an (A,B)‐invariant subspace, we prove that the set of friend feedbacks is a linear variety, which can be considered as the direct sum of the feedbacks of the restriction to ?? and the co‐restriction to ??⊥. In particular, when the natural controllability hypothesis hold, both pole assignments are simultaneously possible by means of a convenient friend feedback. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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We provide a generalization of a recent result of Anastassiou related to thewell-known Ostrowski inequality, as well as some related results. Ourresults subsume, extend, and consolidate a number of known results. 相似文献
96.
J. Quispe-Marcatoma C. Rojas-Ayala C. V. Landauro M. A. de Sousa F. Pelegrini M. Taquire V. A. Pe?a Rodriguez E. M. Baggio-Saitovitch 《Hyperfine Interactions》2011,199(1-3):1-8
We have measured several Q values at JYFLTRAP for superallowed ?? decays that contribute to testing the Standard Model and candidate nuclei that one could use for the search of neutrinoless double-?? decay. These results play important roles in the research of fundamental physics that have scopes beyond Standard Model. 相似文献
97.
Hexachloroosmate(IV) effectively catalyzes the photodecomposition of chloroform in aerated solutions. The decomposition products are consistent with a mechanism in which excited state OsCl62− reduces chloroform, rather than one involving photodissociation of chlorine atoms. Trace amounts of ethanol or water in the chloroform lead to photosubstitution to form OsCl5(EtOH)− or OsCl5(H2O)−, neither of which is photocatalytically active. 相似文献
98.
Mayté Paredes Zaldivar Norma Galego Fernández Cristina Gastón Peña Manuel Rapado Paneque Sonia Altanés Valentín 《Journal of Thermal Analysis and Calorimetry》2011,106(3):725-730
A new polyacrylic acid/polyhydroxybutyrate semi-interpenetrating polymer network hydrogel, the s-IPN/PAA-PHB, was prepared
by a gamma radiation-induced polymerization. Thermal behavior was studied by thermogravimetric analysis (TG) and Differential
scanning calorimetry (DSC), while the s-IPNs composition, FTIR spectra, and swelling kinetics were also determined. It was
found that the DSC curve showed a melting point which is attributed to polyhydroxybutyrate. The TG curves showed various stages
of degradation which are in correspondence of the presence of crosslinked polyacrylic acid and confirmed the higher thermal
stability of the polymer network. The s-IPN/PAA-PHB composition was 10% of PHB and 90% of PAA. Moreover, the network reached
approximately 600% of swelling in water, so it behaves like a superabsorbent hydrogel. 相似文献
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The research of the two last authors has been supported by DGICYT (Spain) PS88-0085. 相似文献