Cyano-bridged coordination polymer nanoparticles with high nuclear relaxivity: toward new contrast agents for MRI

New water-soluble paramagnetic Gd-containing cyano-bridged metallic coordination polymer nanoparticles with a chitosan shell show high nuclear relaxivity in acidic water which is up to six times higher than that of the actually used Gd-chelates.     

A parameter-free unconstrained reformulation for nonsmooth problems with convex constraints

Computational Optimization and Applications - In the present paper we propose to rewrite a nonsmooth problem subjected to convex constraints as an unconstrained problem. We show that this novel...     

High-order Levi curvatures and classification results

In this paper we write some differential formulas involving the high-order Levi curvatures of a real hypersurface in a complex space form. As application we get a classification result under suitable assumptions.     

High-resolution inelastic x-ray scattering to study the high-frequency atomic dynamics of disordered systems

The use of momentum-resolved inelastic x-ray scattering with meV energy resolution to study the high-frequency atomic dynamics in disordered systems is here reviewed. The typical realization of this experiment is described together with some common models used to interpret the measured spectra and to extract parameters of interest for the investigation of disordered systems. With the help of some selected examples, the present status of the field is discussed. Particular attention is given to those results which are still open for discussion or controversial, and which will require further development of the technique to be fully solved. Such an instrumental development seems nowadays possible at the light of recently proposed schemes for advanced inelastic x-ray scattering spectrometers. To cite this article: G. Monaco, C. R. Physique 9 (2008).     

Visible-Light Assisted Covalent Surface Functionalization of Reduced Graphene Oxide Nanosheets with Arylazo Sulfones

We present an environmentally benign methodology for the covalent functionalization (arylation) of reduced graphene oxide (rGO) nanosheets with arylazo sulfones. A variety of tagged aryl units were conveniently accommodated at the rGO surface via visible-light irradiation of suspensions of carbon nanostructured materials in aqueous media. Mild reaction conditions, absence of photosensitizers, functional group tolerance and high atomic fractions (XPS analysis) represent some of the salient features characterizing the present methodology. Control experiments for the mechanistic elucidation (Raman analysis) and chemical nanomanipulation of the tagged rGO surfaces are also reported.     

EPR STUDIES ON SINGLET OXYGEN PRODUCTION BY PORPHYRINS

Abstract— EPR studies of the porphyrin-sensitized photooxidation of 2, 2, 6,6-tetramethyl-piperidine to the nitroxide demonstrate that all the porphyrins examined are able to generate ¹O₂, although the efficiency of the photoprocess is dependent on the nature of the side chains. Incorporation of metal ions into the porphyrin molecule depresses or even inhibits the formation of ¹O₂. Comparison of these results with previously obtained kinetic data points out that the efficiency of porphyrins as photosensitizes is controlled by the lifetime of their lowest triplet state.     

Preparation of coatings via cationic photopolymerisation: influence of alcoholic additives

Coatings obtained through photopolymerisation of vinylethers, propenyl ethers and epoxy resins are described. The influence of alcohols and of comonomers bearing OH groups on the cationic mechanism of the curing process is discussed. The final properties of the coatings are evaluated and correlated to the structures of the additives.     

New Vistas in Frontal Polymerization

Frontal Polymerization is a technique for the synthesis of polymers that, by exploiting the heat liberated by the self-same reaction, generates a hot front that can sustain and propagate itself from one end of the reactor to the other converting monomer into polymer. After the activation and following formation of the front, it is not necessary to provide any other form of energy in order to carry out polymerization. In this article we will summarize some of the recent results we have obtained in the application of Frontal Polymerization to the preparation of polyurethanes, unsaturated polyester resins, and polyacrylates.