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In this work, the introduction of small variations in the electrical impedance ofHF (High Frequency) RFID (Radio Frequency Identification) tags has been exploited in the proximity sensing of temperature by applying Polyvinylidene Fluoride (PVDF) interdigital capacitive sensors as a modification of the transponder’s circuitry. The adopted electrical parasitic sensing load introduces a shift in the primary resonance peakof the tag. Theimpedance spectra have been acquired by a dedicated laboratory setup allowing to apply simultaneously thermal forcing and RF signals to the transponder itself. Thesensitivity of the modified taghas been assessed after taking into account the thermal response of the transponder chipwhich is relevant in the formulation of thermal-sensing transponders.

POC polymer is an oxadiazole-carbazole copolymer we have previously synthetized and established as light emitting material in Organic Light Emitting Devices (OLEDs), although POC quantum yield emission efficiency and color purity still need to be enhanced. On the other hand, tris[2-phenylpyridinato-C2,N]iridium(III) (Ir(ppy)3) complexes, namely Ir(ppy)3 are among the brightest luminophores employed in green light emitting devices. Our aim, in this work, is to take advantage of Ir(ppy)3 bright emission by combining the Ir complex with blue emitting POC to obtain tunable light emitting composites over a wide range of the visible spectrum. Here we have investigated the optical proprieties POC based nanocomposites with different concentrations of Ir(ppy)3, ranging from 1 to 10 wt%. Both spectral and time resolved fluorescence measurements show an efficient energy transfer from the polymer to the dopants, resulting in white-emitting composites. The most intense and stable emission has been found when POC was doped with about 5 wt% concentration of Ir(ppy)3. © 2016 Elsevier B.V.

Two red emitters InP/ZnS quantum dots (QDs) (absorption 570 nm/emission 605 nm and absorption 597/emission 624) were inserted at different concentrations in the blue emitting polymer poly(9,9'- dioctylfluorene) (PFO). Nanocomposites were obtained by mixing the QDs as purchased and the polymer dissolved in the appropriate solvent and deposited by spin coating to give homogeneous films. The morphological properties were characterized by scanning electron microscopy (SEM), that showed a good level of dispersion of the QDs within the polymer. The study of the optical and electrooptical properties of the nanocomposites layer inserted in OLED devices (glass/ITO/PEDOT:PSS/PFO-QD/Ca/Al) is reported and compared to pure polymer based device. Photoluminescence and electroluminescence spectra show an energy transfer from the polymer to QDs in presence of the nanocomposites containing InP/ZnS quantum dots that absorb at 570 nm. © 2013 American Scientific Publishers.

In this work, we studied energetic and optical proprieties of a polyester-containing oxadiazole and carbazole units that we will indicate as POC. This polymer is characterized by high photoluminescence activity in the blue region of the visible spectrum, making it suitable for the development of efficient white-emitting organic light emission devices. Moreover, POC polymer has been combined with two red emitters InP/ZnS quantum dots (QDs) to obtain nanocomposites with wide emission spectra. The two types of QDs have different absorption wavelengths: 570 nm [InP/ZnS(570)] and 627 nm [InP/ZnS(627)] and were inserted in the polymer at different concentrations. The optical properties of the nanocomposites have been investigated and compared to the ones of the pure polymer. Both spectral and time resolved fluorescence measurements show an efficient energy transfer from the polymer to QDs, resulting in white-emitting nanocomposites. © Springer Science+Business Media Dordrecht 2013.

In the present study we investigated a combination of quantum dots with multi-walled carbon nanotubes as a possible future additive to the active layer of polymer solar cells. In this case the quantum dots should serve to enhance the long wavelength response of the solar cell, while the nanotubes enhance the charge carrier collection efficiency by favoring charge carrier separation and enhancement of the lateral conduction of the films. In order to clarify the interplay of the nanoparticles only, we deposited them into a non-conducting and transparent polymethyl-methalacrylate (PMMA) matrix. InP/ZnS quantum dots with an emission peak wavelength of 660 nm have been chosen in this study, because their addition can enhance the long wavelength response of conventional poly(3-hexylthiophene) (P3HT): phenyl-C61-butyric acid methyl ester (PCBM) bulk heterostructure polymer solar cells. In our study we kept the quantum dot concentration constant and varied the concentration of the carbon nanotubes (CNTs) in the deposited films. The characterization of the film morphology by scanning electron microscopy (SEM) imaging and of the optical properties by photoluminescence and transmittance revealed a rather complex interplay between nanotubes and quantum dots. In particular we found a strong quenching of the photoluminescence and an inhomogeneous CNT distribution for carbon nanotube concentrations exceeding 1%. The decrease in optical transmittance of the films with increasing CNT concentration is less pronounced, when quantum dots (QDs) are added. The optical transmittance in a wavelength range between 380 nm and 800 nm of the composites could be expressed empirically as a simple second order polynomial function. © 2013 Elsevier B.V. All rights reserved.

From December 2008 the Italian region of Lombardy started offering the vaccine against HPV to all schoolgirls aged 12. Many topics like knowledge, organization and acceptability should be addressed. This study investigated the compliance to the first vaccination campaign in two suburbs of Milan and assessed the knowledge about HPV and cervical cancer among the mothers of the recipients and the opinions of the healthcare professionals about the campaign by using anonymous multiple choice questionnaires. Knowledge about HPV among mothers went from 63% to 76% after vaccination. Healthcare professionals gave an average grading of 5.7 (scale 1–10) about organization and management of the campaign. Coverage of the immunization campaign was quite poor: after the first round only 55.3% got vaccinated with the first dose. Knowledge of mothers of the recipients is still to improve, particularly among immigrants and less educated. It is necessary to implement information campaigns to improve knowledge about HPV and the acceptability of the new vaccine.