Publications by authors named "Monica Tirado"

Postharvest fungal diseases are the main cause of economic losses in lemon production. The continued use of synthetic fungicides to control the diseases favors the emergence of resistant strains, which encourages the search for alternatives. The aim of this study was to assess the efficacy of metallic nanoparticles (NPs) as antifungal agents against local isolates of and , each of them in a fungicide-sensitive and -resistant version, and a isolate.

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Heteroleptic ruthenium (II) complexes were used for sensitizing ZnO surfaces in organic solar cells (OSCs) as mediators with photoactive layers. The complexes [Ru(4,4'-X-bpy)(Mebpy-CN)] (with X = -CH, -OCH and -N(CH); bpy = 2,2'-bipyridine; Mebpy-CN = 4-methyl-2,2'-bipyridine-4'-carbonitrile) were synthesized and studied by analytical and spectroscopical techniques. Spectroscopic, photophysical, and electrochemical properties were tuned by changing the electron-donating ability of the -X substituents at the 4,4'-positions of the bpy ring and rationalized by quantum mechanical calculations.

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We report in this work the synthesis and spectroscopic, electrochemical, spectroelectrochemical, and photophysical characterization of a novel series of ruthenium polypyridyl complexes with 4-methyl-2,2'-bipyridine-4'-carbonitrile (Mebpy-CN) as an auxiliary ligand of general formula [Ru(bpy)3-x(Mebpy-CN)x](PF6)2 (x = 1-3) (with bpy = 2,2'-bipyridine). A significant increase in the lifetime and quantum yield of emission of the lowest (3)MLCT excited state is disclosed when going from x = 1 to x = 3, evidencing an improvement of the photosensitizing properties with respect to [Ru(bpy)3](PF6)2. Furthermore, quenching by molecular oxygen of (3)MLCT excited states of the three complexes produced singlet molecular oxygen ((1)O2) with quantum yield values higher than that of [Ru(bpy)3](2+) in CH3CN.

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Dielectric properties of four suspensions of spherical polystyrene particles were measured at 25 degrees C over a broad frequency range extending from 100 Hz to 10 MHz, using a HP 4192 A Impedance Analyzer. The instrument was coupled to a cell with parallel platinum black electrodes and variable spacing, and the quadrupole calibration method was used. The aqueous electrolyte solutions were prepared using equal concentrations of NaCl, KCl, NaAc, or KAc, so that the calculated Debye screening length and Zeta potential remained constant, while the conductivity changed.

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In a previous paper, a new dielectric technique was used to estimate hematocrit (HTC) in extracorporeal blood circulation systems, independently of plasma conductivity or osmolarity. Although many impedance techniques have been formerly proposed in the literature, none has been evaluated against plasma conductivity and osmolarity. Herein, we estimate HTC based on permittivity changes and also with other four techniques found in the literature.

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Based on permittivity changes, a new method to measure hematocrit (HCT) in extracorporeal blood systems is presented. Human blood samples were tested at different HCT levels pairing the values of permittivity change, obtained by means of a commercial impedance analyzer, with traditional centrifugation measurements. Data were correlated using both linear and nonlinear regression.

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