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181.
182.
Alfonso GonzálezAravind Dasari Berta HerreroEmeric Plancher Julio SantarénAntonio Esteban Szu-Hui Lim 《Polymer Degradation and Stability》2012,97(3):248-256
To understand and improve the fire retardancy behavior of polylactic acid, we have incorporated two structurally different additives, sepiolite and organically modified montmorillonite. A novel approach (combination of electrospinning and extrusion/injection molding) is employed to address critical issues like char enhancement as well as the homogeneity/uniformity of the inorganic barrier during combustion of polymer nanocomposites. Fundamental knowledge is gained on the mechanisms of fire retardancy, particularly with samples of different thicknesses (thermally thin versus thermally intermediate/thick). Volumetric imaging of the residues provided a deeper understanding of the formation or the evolution of the inorganic barrier. Considerable insight on the dependency of biodegradation on the environment (primarily) and on the compromising effect of high aspect ratio nanoparticles is also obtained. This knowledge has a broader scientific impact and is critical to design the new generation of eco-benign flame retardant and biodegradable polymer nanocomposites. 相似文献
183.
Manuel Molina Manuel Mota Alfonso Ramos 《Methodology and Computing in Applied Probability》2012,14(1):35-48
In this paper we introduce a class of two-sex branching models where, in each generation, a random control on the number of
progenitor couples in the population is considered. For such a class, several probabilistic results are established. Also
assuming offspring probability distribution belonging to the bivariate power series family, Bayes estimators for the mean
vector and the covariance matrix of the offspring distribution are proposed. A computational method to determine highest posterior
density credibility sets is stated. As illustration, a simulated example is provided. 相似文献
184.
Alberto Ceccon Annalisa Bisello Laura Crociani Alessandro Gambaro Paolo Ganis Francesco Manoli Saverio Santi Alfonso Venzo 《Journal of organometallic chemistry》2000,600(1-2):94-111
The Rh(COD) and Ir(COD) homobimetallic complexes of s-indacene-diide, 2,6-dimethyl-s-indacene-diide, as-indacene-diide, and 2,7-dimethyl-as-indacene-diide have been synthesized from the di-lithium salts of the dianions and metal dimers [M(μ-Cl)L2]2 (M = Rh, Ir; L2 = COD, NBD, (ethylene)2, (CO)2 as mixtures of syn and anti isomers. The syn/anti ratio depends on the nature of the ancillary ligands at the metal and on the s or as geometry of the bridging ligand. In the reaction of the 2,7-dimethyl-as-indacene-diide-[M(COD)]2 species with CO, the higher reactivity of the syn isomers has been justified on the basis of a greater instability of the ground state due to steric interactions between the COD groups. Bis-η1 metal-bonded intermediates have been identified in the carbonylation of iridium derivatives; on the other hand, the formation of the bis-η5 mixed complexes syn and anti-{2,7-dimethyl-as-indacene-diide-[Rh(COD)][Rh(CO)2]} and their reactivity strongly support the existence of metal---metal interaction in the rhodium derivatives. 相似文献
185.
Eva Garrido Dr. María Alfonso Dr. Borja Díaz de Greñu Beatriz Lozano-Torres Dr. Margarita Parra Dr. Pablo Gaviña Dr. M. Dolores Marcos Prof. Ramón Martínez-Máñez Dr. Félix Sancenón 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(13):2813-2816
This work reports the synthesis, characterization, and sensing behavior of a hybrid nanodevice for the detection of the potent abuse drug 25I-NBOMe. The system is based on mesoporous silica nanoparticles, loaded with a fluorescent dye, functionalized with a serotonin derivative and capped with the 5-HT2A receptor antibody. In the presence of 25I-NBOMe the capping antibody is displaced, leading to pore opening and rhodamine B release. This delivery was ascribed to 5-HT2A receptor antibody detachment from the surface due to its stronger coordination with 25I-NBOMe present in the solution. The prepared nanodevice allowed the sensitive (limit of detection of 0.6 μm ) and selective recognition of the 25I-NBOMe drug (cocaine, heroin, mescaline, lysergic acid diethylamide, MDMA, and morphine were unable to induce pore opening and rhodamine B release). This nanodevice acts as a highly sensitive and selective fluorometric probe for the 25I-NBOMe illicit drug in artificial saliva and in sweets. 相似文献
186.
Adsorption kinetic studies are conducted to investigate the potential to use chiral mesoporous materials nanoporous guanosine monophosphate material-1 (NGM-1) and nanoporous folic acid material-1 (NFM-1) for the enantiomeric separation of l- and d-valine. A pseudo-second-order (PSO) kinetic model is applied to test the experimental adsorption equilibrium isotherms, according to both the Langmuir and Freundlich models and the characteristic parameters for each model are determined. The calcined versions of both NGM-1 and NFM-1 fit the Langmuir model with maximum sorption capacities of 0.36 and 0.26 g/g for the preferred adsorption enantiomers, d-valine and l-valine, respectively. Experimental results and the analysis of adsorption models suggest a strong adsorbate–adsorbent interaction, and the formation of a monolayer of tightly packed amino acid on the internal mesopore surface for the preferred enantiomers. 相似文献
187.
Benigno Macías Isabel García María V. Villa Joaquín Borrs Alfonso Castieiras Francisca Sanz 《无机化学与普通化学杂志》2003,629(2):255-260
Sulfonamides obtained by reaction of 8‐aminoquinoline with benzenesulfonyl, toluene‐4‐sulfonyl and naphthalene‐2‐sulfonyl chlorides have been used to synthetize coordination compounds with ZnII with a ZnL2 composition. Determination of the crystal structures for the resulting complexes by X‐ray diffraction shows a distorted tetrahedral environment for the Zn2+ ions, sulfonamides acting as bidentate ligands through the nitrogen atoms from the sulfonamidate and quinoline groups. FT‐IR, 1H and 13C NMR and mass spectra of these compounds are also discussed. 相似文献
188.
189.
Alfonso Villani 《Rendiconti del Circolo Matematico di Palermo》1984,33(3):331-335
Sia ? una funzione invertibile, continua e quasi ovunque differenziabile, da un aperto di IR n in IR n . Allora ??1soddisfa alla condizione di Lusin (N) se e solo se lo Jacobiano di ? è quasi ovunque diverso da zero. 相似文献
190.
Angel Alberola Celia Andrés Alfonso González Ortega Rafael Pedrosa 《Journal of heterocyclic chemistry》1984,21(5):1575-1576
A new regiospecific synthesis of 1-aryl-substituted pyrazoles by reaction of aryl-hydrazines with β-aminoenones is reported. 相似文献