Search results for " Modification"

Development of stir bar sorptive-dispersive microextraction mediated by magnetic nanoparticles and its analytical application to the determination of…

2014

A novel microextraction technique combining the principles of stir bar sorptive extraction (SBSE) and dispersive micro-solid phase extraction (DμSPE) is presented. The main feature of the method is the use of a neodymium-core stirring bar physically coated with a hydrophobic magnetic nanosorbent. Depending on stirring speed, the magnetic sorbent either acts as a coating material to the stir bar, thus affording extraction alike SBSE, or as a dispersed nanosorbent medium for the collection and extraction of the target analytes, in close analogy to DμSPE. Once the stirring process is finished, the strong magnetic field of the stir bar prevails again and rapidly retrieves the dispersed MNPs. Al…

Multifunctional two-photon active silica-coated Au@MnO Janus particles for selective dual functionalization and imaging.

2014

Monodisperse multifunctional and nontoxic Au@MnO Janus particles with different sizes and morphologies were prepared by a seed-mediated nucleation and growth technique with precise control over domain sizes, surface functionalization, and dye labeling. The metal oxide domain could be coated selectively with a thin silica layer, leaving the metal domain untouched. In particular, size and morphology of the individual (metal and metal oxide) domains could be controlled by adjustment of the synthetic parameters. The SiO2 coating of the oxide domain allows biomolecule conjugation (e.g., antibodies, proteins) in a single step for converting the photoluminescent and superparamagnetic Janus nanopar…

Microwave assisted syntheses of solvent-based colloidal sols of tailored ceria nanoparticles

2009

AbstractMicrowave assisted syntheses of stable solvent based colloidal sols of tailored ceria nanoparticles Olivier Poncelet*, Julien Jouhannaud*, Denis Chaumont** *CEA Liten DTNM/L2T , 17 rue des Martyrs F-38054 Grenoble Cedex9, France **Institut Carnot Bourgogne (ICB), UMR5209 CNRS, Facult� des Sciences Mirande, Universit� de Bourgogne, 9 Av. Alain Savary, BP 47870, F-21078 Dijon Cedex The pressure of environmental laws in many advanced countries becoming more restricting year after year, it is asked to automobile companies to strongly control the carburant consumption of cars that they put on the market and also to eliminate toxic chemicals coming from exhaust emission gases. This is par…

Evaluation of 2,3-epoxypropyl groups and functionalization yield in glycidyl methacrylate monoliths using gas chromatography

2014

Abstract Poly(glycidyl methacrylate- co -ethylene dimethacrylate) (poly(GMA- co -EDMA)) is most frequently used as parent monolith to obtain stationary phases with a variety of surface chemistries for liquid chromatography and capillary electrochromatography. Functionalization is performed by opening the accessible 2,3-epoxypropyl groups of the monolith with a suitable reagent. The number of 2,3-epoxypropyl groups which are accessible before and after the functionalization reaction, and the grafting yield, are important parameters, required both to optimize functionalization and to interpret the chromatographic performance of functionalized monoliths. In this work, a method capable of provi…

Heterobimetallic single-source precursors for MOCVD. Synthesis and characterization of volatile mixed ligand complexes of lanthanides, barium and mag…

1999

Several heterobimetallic complexes of general formula [(M 1 Q) m M 2 (dik) n ], where (M 1 Q) is Cu(salen) or Ni(salen) and M 2 (dik) n is a lanthanide tris(β-diketonate) or an alkali-earth element bis(β-diketonate) with more or less fluorinated diketonato(-) ligands, have been prepared and structurally characterized. Some of them were submitted to thermal and mass spectrometry analyses, and to isothermal vacuum sublimation tests, in view of their potential use as MOCVD single-source precursors for the deposition of heterobimetallic materials. The study stresses upon the influence of the nature of the diketone. of the M 2 cation, and of chemical modification of the salen ligand on the therm…

The EPPS16 nuclear PDFs

2017

We report on EPPS16 - the first analysis of NLO nuclear PDFs where LHC p-Pb data (Z, W, dijets) have been directly used as a constraint. In comparison to our previous fit EPS09, also data from neutrino-nucleus deeply-inelastic scattering and pion-nucleus Drell-Yan process are now included. Much of the theory framework has also been updated from EPS09, including a consistent treatment of heavy quarks in deeply-inelastic scattering. However, the most notable change is that we no longer assume flavour-blind nuclear modifications for valence and sea quarks. This significantly reduces the theoretical bias. All the analysed data are well reproduced and the analysis thereby supports the validity o…

Microfibrillar polymeric ocular inserts for triamcinolone acetonide delivery.

2019

Abstract Despite eye drops generally represent the most convenient, simple and patient-friendly formulations to treat ocular diseases, they suffer from poor retention on the ocular surface and low drug bioavailability leading to the necessity of prolonged and continuous treatment over time. Therefore, ocular insert could represent an innovative way to benefit from ocular topical administration while minimizing all the relevant limitation related to this route of administration. Polymeric non-erodible mucoadhesive ocular inserts should be comfortable and should rapidly adhere on the ocular surface, remain in situ for prolonged period, assure a reproducible and controlled drug release as well…

Pectin as Drug-Release Vehicle

2020

Pectin as a natural biopolymer is extensively used for pharmaceutical and biomedical applications, essentially due to its gelling properties that could be influenced by pectin sources and extraction methods. This chapter focuses on an overview of pectin drug delivery systems classified by their administration routes. Oral drug delivery systems have been mainly developed, as pectin could be used in tablets as binder or matrix excipients and in microparticles/beads obtained by ionotropic gelation. The main objective is to target the colon, as pectin is resistant in acidic pH and sensitive to pectinolytic enzymes in the colon. To obtain suitable properties, pectin could be used in its native s…

Asphalt mixtures improved with plastic additives: mix design and case study in an airport

La crescente domanda di prestazioni e le esigenze di salvaguardia dell’ecosistema spingono a sviluppare nuove tecnologie di lavorazione, a sperimentare l’impiego di nuovi materiali, a migliorare i metodi di progetto delle miscele. Il criterio seguito è quello di un impiego più razionale delle risorse e dell’utilizzo di tecniche a basso impatto ambientale. Per ragioni tecniche ed economiche stiamo assistendo al fenomeno di espansione nel mercato degli additivi, impiegati nella produzione di miscele bituminose per migliorarne le prestazioni e ridurre i costi. In generale, però riuscire a soddisfare tutti gli obiettivi con un unico prodotto è difficile, perché l’alta qualità richiede costi più…

Long-term analysis (1863–2002) of environmental change in the Capo Feto area (Mediterranean sea)

2004

The area of Capo Feto represents one of the few remaining salt-marshy zones in Sicily. It lies within a site of importance for the Community (defined as a “sito di importanza comunitaria” (SIC)), which also includes Margi Spanò and Margi Milo. The Capo Feto and Margi Spanò marshlands have also been identified by the Ministry for the Environment as an area deserving special protection (“zona a protezione speciale” (ZPS)). Moreover, in 1999, 150 ha of the Capo Feto area were included in a project for environmental rehabilitation as part of the European Union “Life-Nature 2000” programme (Comitato Tecnico-Scientifico Area di Capo Feto, 1997). Prior to this, the area had become somewhat degrade…