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101.
102.
The association and photobehavior of Rose Bengal (RB) in the presence of dipalmitoylphosphatidyl choline (DPPC) small unilamellar liposomes is determined by the temperature. At temperatures above the main phase transition of the bilayer, the incorporation of the dye is ca. 2.5 times more efficient than that taking place when the bilayer is in the gel state. In both temperature ranges, adsorption isotherms show a noticeable anti-cooperativity that can be related to electrostatic repulsion between bound molecules. The photophysics and the photochemistry of the bound dye molecules also depend on the bilayer status. In particular, in the liquid crystalline state the surrounding of the dye is more polar and production of singlet oxygen is less efficient (Φ∼0.1). This reduced singlet oxygen production is partially due to a low triplet yield (ΦT=0.35) and triplet self-quenching due to a high local RB concentration. In spite of these, tryptophan is efficiently photobleached when RB is associated to liposomes in the liquid crystalline state, probably due to a Type I mechanism favored by its high local concentration in the sensitized surroundings. 相似文献
103.
Joaquín Díaz Iñaki López Emilio Nogales Bianchi Méndez Javier Piqueras 《Journal of nanoparticle research》2011,13(5):1833-1839
Silicon-doped gallium oxide nanowires have been synthesized by thermal methods using either a mixture of gallium oxide and
silicon powders or metallic gallium with silicon powder as precursor materials. The growth mechanism has been found to be
a vapour–liquid–solid (VLS) or vapour–solid (VS) process, respectively, depending on the precursor used. In the former case,
silicon oxide droplets at the end of the nanowires have been observed. Their possible role during the growth of the nanostructures
is discussed. Structural and morphological characterization of the doped nanowires has been performed by transmission electron
microscopy (TEM) and scanning electron microscopy (SEM). The results show a high crystalline quality and a uniform distribution
of silicon along the nanowires. Room temperature cathodoluminescence (CL) in the SEM shows that slight variations in the composed
UV–blue emission band appear due to the influence of Si impurities in the oxygen vacancy defect structure. 相似文献
104.
Emilio L. Cano Javier M. Moguerza Tatiana Ermolieva Yuri Ermoliev 《Computational Management Science》2014,11(1-2):25-44
Due to deregulations of the energy sector and the setting of targets such as the 20/20/20 in the EU, operators of public buildings are now more exposed to instantaneous (short-term) market conditions. On the other hand, they have gained the opportunity to play a more active role in securing long-term supply, managing demand, and hedging against risk while improving existing buildings’ infrastructures. Therefore, there are incentives for the operators to develop and use a Decision Support System to manage their energy sub-systems in a more robust energy-efficient and cost-effective manner. In this paper, a two-stage stochastic model is proposed, where some decisions (so-called first-stage decisions) regarding investments in new energy technologies have to be taken before uncertainties are resolved, and some others (so-called second-stage decisions) on how to use the installed technologies will be taken once values for uncertain parameters become known, thereby providing a trade-off between long- and short-term decisions. 相似文献
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106.
Alfredo Burrieza Inmaculada P. de Guzmán Emilio Muñoz‐Velasco 《Mathematical Logic Quarterly》2010,56(1):89-102
In previous works, we presented a modification of the usual possible world semantics by introducing an independent temporal structure in each world and using accessibility functions to represent the relation among them. Different properties ofthe accessibility functions (being injective, surjective, increasing, etc.) have been considered and axiomatic systems (called functional) which define these properties have been given. Only a few ofthese systems have been proved tobe complete. The aim ofthis paper is to make a progress in the study ofcompleteness for functional systems. For this end, we use indexes as names for temporal flows and give new proofs of completeness. Specifically, we focus our attention on the system which defines injectivity, because the system which defines this property without using indexes was proved to be incomplete in previous works. The only system considered which remains incomplete is the one which defines surjectivity, even ifwe consider a sequence ofnatural extensions ofthe previous one (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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108.
Roberta Cavalli Emilio Marengo Otto Caputo Elena Ugazio Maria Rosa Gasco 《Journal of Dispersion Science and Technology》2013,34(7):717-734
The influence of twenty five different alcohols on the formation of warm oil-in-water (O/W) microemulsions was investigated. Selected concentrations of each alcohol were added to fixed amounts of stearic acid, Tween 20 and water at 65 ° C. Fifteen alcohols formed microemulsions, at least at one of the concentrations. A pattern recognition study was performed to elucidate the activities of the alcohols by Principal Component Analysis (PCA). Linear Discriminant Analysis (LDA) was used to classify them. Two classification functions, obtained for alcohols forming / not forming microemulsions, suggest that the formation of warm O/W microemulsion is linked to the nature and the dimension/lipophilicity of the alcohol. 相似文献
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Postsynthetic Improvement of the Physical Properties in a Metal–Organic Framework through a Single Crystal to Single Crystal Transmetallation
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Thais Grancha Dr. Jesús Ferrando‐Soria Prof. Dr. Hong‐Cai Zhou Prof. Dr. Jorge Gascon Dr. Beatriz Seoane Dr. Jorge Pasán Dr. Oscar Fabelo Prof. Dr. Miguel Julve Dr. Emilio Pardo 《Angewandte Chemie (International ed. in English)》2015,54(22):6521-6525
A single crystal to single crystal transmetallation process takes place in the three‐dimensional (3D) metal–organic framework (MOF) of formula MgII2{MgII4[CuII2(Me3mpba)2]3}?45 H2O ( 1 ; Me3mpba4?=N,N′‐2,4,6‐trimethyl‐1,3‐phenylenebis(oxamate)). After complete replacement of the MgII ions within the coordination network and those hosted in the channels by either CoII or NiII ions, 1 is transmetallated to yield two novel MOFs of formulae Co2II{CoII4[CuII2(Me3mpba)2]3}?56 H2O ( 2 ) and Ni2II{NiII4[CuII2(Me3mpba)2]3}? 54 H2O ( 3 ). This unique postsynthetic metal substitution affords materials with higher structural stability leading to enhanced gas sorption and magnetic properties. 相似文献