New strategies to identify molecular markers predicting chemotherapy activity and toxicity in breast cancer

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A general strategy for the synthesis of conjugated polymers based upon the palladium-catalysed cross-coupling of Grignard reagents with unsaturated halides

Palladium-catalysed cross-coupling between aromatic bisorganomagnesium reagents and aromatic dihalides has been experimentally evaluated as a general methodology for the synthesis of soluble conjugated polymers such as poly(p-phenylene)s 6 and 7, poly(p-terphenylenevinylene) 8, poly(phenylenethiophene) 9 and poly(phenylenepyridine) 10. Appropriate experimental conditions were first found in model reactions and then applied to the synthesis of polymers. Molecular mass values were determined both by GPC and by MALDI-TOF spectrometry. The latter technique also permitted accurate determination of the terminal groups of the polymeric chains. (C) Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002

A non destructive testing method for masonry by using UPV and cross validation procedure

The paper presents a new procedure to assess the compressive strength of regular masonry starting from results of non-destructive ultrasonic pulse velocity tests (UPV) on the constituent materials. The procedure has been calibrated on a soft calcarenitic stone used in the heritage masonry of Southern Italy, and starts from the knowledge of the regression between UPV and the compressive strength (UCS) of the material, determined by means of a wide experimental campaign on different varieties of quarry samples. Through an improved cross validation technique, the proposed method allows to estimate the compressive strength of new samples by making only non-destructive measurements without the need to conduct compression tests. The quality of the procedure was assessed both at the block scale and at the wall scale by comparing the estimated results with those obtained experimentally. In particular, the experiments were performed using new quarry stone blocks and blocks taken from existing walls of two ancient buildings during restoration works. The proposed method has proven to be reliable for the investigated material and it is easy to apply also for other materials as soon as it is possible to carry out a preliminary calibration in the laboratory, which allows knowing the UPV–UCS relationship over a wide range of strengths

Synthesis of poly(aryleneethynylene)s bearing glucose units as substituents

A series of poly(aryleneethynylene)s functionalized with acetylated glucopyranosyl units were synthesized by the Pd-catalyzed reaction of trimethylsilylethynyl derivatives with aromatic halides in the presence of silver oxide

Thin film construction and characterization and gas-sensing performances of a tailored phenylene-thienylene copolymer

An alternating copolymer, poly(2,5-dioctyloxy-1,4-phenylene-alt-2,5-thienylene), has been synthesized and used in this research. The behavior of the floating film at the air-water interface has been investigated by measuring surface pressure versus area Langmuir isotherms and contemporaneously by reflection spectroscopy and Brewster angle microscopy. The floating films were transferred by the Langmuir-Schafer (horizontal lifting) method onto various substrates. It is apparent from these analyses that the effective conjugation length is larger than those in other electroactive polymers and that a strong coplanarity and interchain association takes place above all in the floating film on the water surface and in the transferred multilayers. Such films were used as the active layers in resistive chemical gas sensor devices, thus revealing excellent sensitivity toward NO2, reversibility, and time stability of the response

Synthesis and Chiroptical Characterization of an Amino Acid Functionalized Dialkoxypoly(p-phenyleneethynylene)

2,5-Dialkoxypoly(p-phenyleneethynylene) (3) functionalized with N-t-BOC-L-phenylalanine molecules was synthesized by Pd-catalyzed reaction of dioctyloxybis[(trimethylsilyl) ethynyl] benzene (1) with aromatic diiodide 2 linked to two amino acid units by six carbon atoms alkoxy chains. Optical properties were investigated both in solution and in the solid state (as thin films) by absorption, fluorescence and chiroptical spectroscopies (CD and CPL). Polymer 3, that represents one of few fully characterized dialkoxy-substituted PAEs, is also the first example of a poly(aryleneethynylene) (PAE) with amino acidic chiral pendants

Spectroscopic ellipsometry for characterization of organic semiconductor polymeric thin films

The correlation between the optical properties and microstructural parameters of organic semiconductor polymeric thin films is investigated by spectroscopic ellipsometry. Different poly(arylenephenylene)-based films have been deposited by spincoating. The effect of deposition conditions on the microstructure and, hence, optical constants of the polymeric thin films and the dependence of the optical properties and pi-pi* transition on the structure of the chain backbone are studied. (C) 2003 Elsevier Science B.V. All rights reserved

Study of anisotropic optical properties of poly(arylenephenylene) thin films: Dependence on polymer backbone

The correlation between the optical properties and microstructural parameters of different poly(arylenephenylene) thin films, deposited by spin-coating, is investigated by spectroscopic ellipsometry. Conjugated polymer films are found to be anisotropic. They are birefringent, with a higher refractive index in the plane of the film than perpendicular to it. This anisotropy is due to a preferential in-plane orientation of the polymer chains. The dependence of both the in-plane and out-of-plane optical constants of the polymeric thin films and of the fundamental pi-pi* transition on the structure of the chain backbone are studied. The change of the pi-pi* transition energy of the polymers from solution to thin film and its correlation with the molecular structure are investigated as indicative of interchain interactions