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141.
We define and investigate a class of Koszul quasi-hereditary algebras for which there is a natural equivalence between the bounded derived category of graded modules and the bounded derived category of graded modules over (a proper version of) the extension algebra of standard modules. Examples of such algebras include, in particular, the multiplicity free blocks of the BGG category O, and some quasi-hereditary algebras with Cartan decomposition in the sense of König.  相似文献   
142.
This paper presents categorifications of (right) cell modules and induced cell modules for Hecke algebras of finite Weyl groups. In type A we show that these categorifications depend only on the isomorphism class of the cell module, not on the cell itself. Our main application is multiplicity formulas for parabolically induced modules over a reductive Lie algebra of type A, which finally determines the so-called rough structure of generalised Verma modules. On the way we present several categorification results and give a positive answer to Kostant's problem from [A. Joseph, Kostant's problem, Goldie rank and the Gelfand-Kirillov conjecture, Invent. Math. 56 (3) (1980) 191-213] in many cases. We also present a general setup of decategorification, precategorification and categorification.  相似文献   
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The paper studies radiation‐induced modification of energetic spectra of excitons in CdTe quantum dots (QDs) in a (Cd, Mn)Te matrix. Exciton levels in such system are very sensitive to the changes in Mn concentration due to the exchange interaction between magnetic Mn ions and charge carriers (the giant splitting effect). Radiation‐enhanced diffusion causes Mn penetration into the QD that leads to the changes in the exciton level energy. We found the spatial distribution of Mn ions for different durations of the irradiation and performed quantum calculations of the energy of exciton states with the obtained Mn concentration profiles. The dependences of the position of the exciton levels and the splitting between the energy of exciton states with σ+ and σ polarizations on the irradiation parameters and the QD's radius have been investigated. The calculations show that the irradiation causes a large shift of exciton levels. The splitting between levels with σ+ and σ polarizations may be increased in the order of value due to the irradiation. The radiation effects are stronger for QD with smaller radius.  相似文献   
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The optical absorption spectra of the two‐dimensional crystals of n ‐(C3H7NH3)2CdCl4 induced by X‐ray irradiation at 20 K were studied and compared with those for the as‐received sample. It has been found that X‐irradiation causes effects similar to those observed in the related crystals of (Cn H2n +1NH3)2CdCl4 (n = 1, 2). New optical absorption bands (IR bands) were found in the region 10–17 kcm–1, besides the absorption band of the Cl2 molecular center characteristic of this compound. The absorption intensities of these bands decrease at temperatures higher than 40 K accompanying the decrease of the Cl2 concentration in n‐ (C3H7NH3)2CdCl4 crystals. These IR bands are assigned to the electron‐trapped center where an electron is trapped by an alkylammonium head in the neighborhood of a Cl vacancy. Such a model was found to be in good agreement with the results of the X‐ray luminescence and thermoluminescence study. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
148.
It is proved that, for a metric space X and a normed space Z, the diagonals of pointwise Lipschitz mappings f : X 2? →?Z are exactly stable pointwise limits of pointwise Lipschitz mappings. The joint Lipschitz property of separately pointwise Lipschitz mappings f : X?×?Y?→?Z, where X, Y, and Z are metric spaces, is investigated.  相似文献   
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Conventional photodynamic treatment strategies are based on the principle of activating molecular oxygen in situ by light, mediated by a photosensitizer, which leads to the generation of reactive oxygen species and thereby causes cell death. A diarylethene‐derived peptidomimetic is presented that is suitable for photodynamic cancer therapy without any involvement of oxygen. This light‐sensitive molecule is not a mediator but is itself the cytotoxic agent. As a derivative of the cyclic amphiphilic peptide gramicidin S, the peptidomimetic exists in two thermally stable photoforms that are interconvertible by light of different wavelengths. The isomer generated by visible light shows much stronger toxicity against tumor cells than the UV‐generated isomer. First in vivo applications are demonstrated on a tumor animal model to illustrate how the peptidomimetic can be administered in the less toxic form and then activated locally in a solid tumor by visible light.  相似文献   
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