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91.
This work reports on the photoluminescent properties of three new lanthanide complexes with acetoacetanilide (aaa), a β-diketonate ligand. The complexes have the general molecular formulae [RE(aaa)3(H2O)], they are soluble in organic solvents such as ethanol and chloroform and insoluble in water. The energy of the triplet state was determined at about 4,700 cm?1 higher than the 5D4 emitting level of the Tb(III) ion, leading to an absolute quantum yield of 22 % for the [Tb(aaa)3(H2O)] complex. The photoluminescent properties were studied and the luminescence parameters of the [Eu(aaa)3(H2O)] complex were experimentally determined. The photostabilities of the complexes under continuous UV irradiation were measured and the data indicate low stability of the [Tb(aaa)3(H2O)] complex when the system is excited at the band attributed to energy transfer from the ligand to terbium(III) ion. However, its photostability is significantly improved under inert atmosphere. 相似文献
92.
Thallium(III)trinitrate trihydrate (TTN) is known to be a useful and extremely versatile reagent in organic synthesis.1-5 Its use has been exploited mainly in oxidation and oxidative rearrangements of chalcones, aromatic ketones and phenols. In this communication, we report an unusual reaction of polyoxygenated methylbenzoates with TTN. 相似文献
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Luís Antônio Dantas Silva Fernanda Vieira Teixeira Raphael Caixeta Serpa Najla Locatelli Esteves Rayane Ramos dos Santos Eliana Martins Lima Marcílio Sérgio Soares da Cunha-Filho Adriano Antunes de Souza Araújo Stephânia Fleury Taveira Ricardo Neves Marreto 《Journal of Thermal Analysis and Calorimetry》2016,123(3):2337-2344
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J. Silva-Valencia A. M. C. Souza 《The European Physical Journal B - Condensed Matter and Complex Systems》2012,85(1):5
The properties of the wave transmission in the lossy single-negative (SNG) metamaterials
are experimentally investigated. The model structure of lossy epsilon-negative (ENG)
monolayer and SNG bilayer consisting of a lossy ENG material and a mu-negative (MNG) are
considered in this work. Simulation and experimental results show that the transmittance
of the lossy SNG materials can be enhanced by two approaches, increasing dissipation
coefficient and increasing the thickness of the lossy SNG. The lossy ENG material is
physically fabricated by using composite right- and left-handed transmission lines grafted
with radiation unit cell. The experimental results are in very good agreement with the
previous theoretical analysis. 相似文献
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Plínio T. Berardo Maurício S. Abrao Maísa L.S. Souza Daniel E. Machado Luiz-Cláudio F. Silva Luiz E. Nasciutti 《Micron (Oxford, England : 1993)》2009,40(5-6):639-645
The composition of sulfated glycosaminoglycans (GAGs) and the tissue distribution of chondroitin sulfate (CS) were analyzed in deeply infiltrating endometriosis (DIE) of rectosigmoid, using metachromatic staining, and biochemical analysis employing electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against CS. The sulfated GAGs were characterized as dermatan sulfate (DS), heparan sulfate (HS) and CS; and DS strongly predominated compared to HS and CS. Immunostaining procedures showed that CS was concentrated in the endometriosis foci, distributed throughout the stroma around the glands. This is the first report describing the composition of sulfated GAGs and the tissue location of CS in DIE by means of histochemical, biochemical and immunohistochemical analyses. These results confirmed that in DIE of rectosigmoid, as in eutopic endometrium [Nasciutti, L.E., Ferrari, R., Berardo, P.T., Souza, M.L.S., Takiya, C.M., Borojevic, R., Abrao, M.S., Silva, L.C.F., 2006. Distribution of chondroitin sulfate in human endometrium. Micron 37, 544–550], CS was the dominant sulfated GAG in stroma of the lesion foci. 相似文献