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961.
Amani Atayat Lucia Mergola Nadia Mzoughi Roberta Del Sole 《Journal of separation science》2019,42(18):3023-3032
The aim of this work was to develop an efficient method for the selective extraction and analysis of fenoxycarb, a carbamate pesticide, in mussel samples using a molecularly imprinted solid‐phase extraction device. The optimization of molecularly imprinted polymer synthesis was performed using the experimental design under the response surface methodology approach. A fast rebinding study and Freundlich isotherm adsorption were carried out to calculate binding capacity B, site number n, and affinity constant Kf. The optimum molecularly imprinted polymer was successfully used as sorbent of a solid‐phase extraction cartridge for the determination of fenoxycarb in real mussel samples. The range of linearity was 0.3–30 mg/L with a correlation coefficient of 0.991. The limit of detection was 0.247 mg/kg. The recovery of fenoxycarb extracted from mussel samples of Mediterranean sea was 97% (n = 3) with relative standard deviation between 6 and 7% proving the reliability of the developed method. 相似文献
962.
Roberta Sburlati 《International Journal of Solids and Structures》2013,50(22-23):3649-3658
The aim of this work is to present an analytical solution to reduce the stress concentration factor (SCF) around a circular hole in an isotropic homogeneous plate subjected to far-field uniaxial loading. In this paper the elastic response of an inhomogeneous annular ring made of functionally graded material (FGM), inserted around a hole of a homogeneous plate, is studied. By assuming that Young’s modulus varies in the radial direction with power law and that Poisson’s ratio is constant, the governing differential equations for plane stress conditions are obtained. Using stress function a general solution in explicit closed form is presented and the SCF investigated to highlight the inhomogeneity effects. Furthermore, the explicit solution for an inner homogeneous ring, with different properties with respect to those of the plate, is explicitly obtained and numerical results are compared between homogeneous ring and FGM ring. 相似文献
963.
Rossana Pasquino Fabio Nicodemi Veronica Vanzanella Roberta Alfani Nino Grizzuti 《Rheologica Acta》2013,52(5):395-401
A detailed rheological study of aqueous solutions of methylhydroxyethylcellulose has been carried out in the presence of different acrylate-based graft polymer used as additive contents. Both polymer components are used in cement formulations to improve the flow performances of the concretes, but no physicochemical studies can be easily found in the literature. The content of the graft polymer has been varied between 0.1 and 2.7 wt% in an aqueous solution with a fixed content of 6.5 wt% of methylhydroxyethylcellulose. Creep curves were performed at different stresses in order to build up the flow curves for the various solutions. We found that the addition of the graft polymer triggers a phase transition, which is made more dramatic by the presence of an external flow. A “flow-phase diagram” has been obtained, which could be used as a guide for determining the critical conditions for the onset of the flow-induced instability. 相似文献
964.
Dr. Marta E. Alberto Prof. Nino Russo Prof. Dr. Carlo Adamo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9162-9168
RuII?PtII complexes are a class of bioactive molecules of interest as anticancer agents that combine a light‐absorbing chromophore with a cisplatin‐like unit. The results of a DFT and TDDFT investigation of a RuII complex and its conjugate with a cis‐PtCl2 moiety reveal that a synergistic effect of the metals makes the assembly a promising multitarget anticancer drug. Inspection of type I and type II photoreactions and spin–orbit coupling computations reveals that the cis‐PtCl2 moiety improves the photophysical properties of the RuII chromophore, ensuring efficient singlet oxygen generation and making the assembly suitable for photodynamic therapy. At the same time, the RuII chromophore promotes a new alternative activation mechanism of the PtII ligand via a triplet metal‐to‐ligand charge transfer (3M LCT) state, before reaching the biological target. The importance of the supramolecular architecture is accurately derived, opening interesting new perspectives on the use of bimetallic RuII?PtII assemblies in a combined anticancer approach. 相似文献
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Dr. Federico Bertani Nicolò Riboni Prof. Federica Bianchi Dr. Giovanna Brancatelli Dr. Elizabeth S. Sterner Dr. Roberta Pinalli Prof. Silvano Geremia Prof. Timothy M. Swager Prof. Enrico Dalcanale 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3312-3319
Two novel triptycene quinoxaline cavitands ( DiTriptyQxCav and MonoTriptyQxCav ) have been designed, synthesized, and applied in the supramolecular detection of benzene, toluene, ethylbenzene, and xylenes (BTEX) in air. The complexation properties of the two cavitands towards aromatics in the solid state are strengthened by the presence of the triptycene moieties at the upper rim of the tetraquinoxaline walls, promoting the confinement of the aromatic hydrocarbons within the cavity. The two cavitands were used as fiber coatings for solid‐phase microextraction (SPME) BTEX monitoring in air. The best performances in terms of enrichment factors, selectivity, and LOD (limit of detection) values were obtained by using the DiTriptyQxCav coating. The corresponding SPME fiber was successfully tested under real urban monitoring conditions, outperforming the commercial divinylbenzene–Carboxen–polydimethylsiloxane (DVB–CAR–PDMS) fiber in BTEX adsorption. 相似文献
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