Biosensing platform combining label-free and labelled analysis using Bloch surface waves

Bloch surface waves (BSW) propagating at the boundary of truncated photonic crystals (1D-PC) have emerged as an attractive approach for label-free sensing in plasmon-like sensor configurations. Due to the very low losses in such dielectric thin film stacks, BSW feature very low angular resonance widths compared to the surface plasmon resonance (SPR) case. Besides label-free operation, the large field enhancement and the absence of quenching allow utilizing BSW coupled fluorescence detection to additionally sense the presence of fluorescent labels. This approach can be adapted to the case of angularly resolved resonance detection, thus giving rise to a combined label-free / labelled biosensor platform. It features a parallel analysis of multiple spots arranged as a one-dimensional array inside a microfluidic channel of a disposable chip. Application of such a combined biosensing approach to the detection of the Angiopoietin-2 cancer biomarker in buffer solutions is reported

Torbidimetri di processo per il controllo di qualità nella cristallizzazione industriale

Nei prodotti cristallini uno dei principali parametri di qualità è rappresentato dalla distribuzione dimensionale e per esso la specifica di prodotto consiste, generalmente, nel contenuto massimo di cristalli al di sotto di una dimensione assegnata. Il presente lavoro riporta i risultati del lavoro di sviluppo di una linea di turbidimetri specificamente concepiti per l'applicazione di processo ed in grado di misurare, in linea o fuori linea, la concentrazione di cristalli fini nello slurry contenente il prodotto basata su un modulo di misura in linea della torbidità associato ad un sistema di separazione della torbida contenente i soli cristalli fini

Laser Welding Head Tailored to Tube-Sheet Joint Requirements for Heat Exchangers Manufacturing

Tube to tube-sheet joints in heat exchangers are currently welded by the orbital TIG process characterized by very high quality of the weld beads and good repeatability. However, due to high number of welds, a reduction in the welding cycle time would have an interesting impact on manufacturing costs and delays and laser welding technology is aimed to improve this factor. The main disadvantage is the positioning accuracy required by the laser welding process since beam deviations from real joint cause lack of penetration. It is expected that the Orbital laser welding head developed under the European project ORBITAL will avoid this drawback

Stationary self-confined beams at 633 nm in B12SiO20 crystals

Self-confinement of light beams at the wavelength of 633 nm is presented for the first time in B12SiO20 (BSO) photorefractive crystals. The 633 nm wavelength is slightly absorbed in BSO, not enough for efficient photorefractive nonlinearity. However, superposing on the 633 nm beam a second beam at 514.5 nm, two-step absorption processes can generate a hot free-carrier population in the conduction band. If a bias voltage is applied, the conducting electric field, responsible for the current flowing inside the crystal, is spatially modulated according to the red-beam profile and a spatial modulation of the material dielectric constant occurs. Efficient self-trapping is demonstrated both from the theoretical and experimental points of view

Light polarization dynamics in self-confined beams and solitons propagating in photorefractive media

Soliton formation in photorefractive crystals with strong optical activity in analysed. We shall demonstrate that self-confinement of the laser beam is not enough to define such a beam "a soliton": in fact this state is completely define by both intensity and polarization soliton dynamics. We report here the characterization of the soliton state for CW and pulsed beams

Carbon nanotube based cold cathodes for a new generation of X-ray systems

Summary. — We present here a new device capable of generating X-rays based on a novel concept of electron source: carbon nanotube-based cold cathodes. In particular, we developed lithographic-based synthesis protocols for obtaining aligned and vertically oriented carbon nanotubes (CNTs) grown by CVD. We report some results obtained in our lab on the characterizations of field emission properties of CNT-based cold cathodes in order to demonstrate that these emitters have the capability to produce self-focused electron beams. Finally we report the results carried out by developing a reliable proof-of-concept of X-ray tube with CNT cold cathodes in the framework of the FP7-SME project NANORAY

Portable nano X-ray diagnostic systems for advanced innovative materials

We present the realization of an innovative device capable of generating X-rays based on a novel concept of cold cathode: carbon nanotube-based electron sources. Taking advantage of the expertise in fabricating CNT-based emitting systems with tailored features, a series of customized cathodes have been produced and tested in our labs. The compact and robust X-ray source designed and tested by the Nanoray Consortium, in the frame of a FP7-SME project, is characterized by fast response time, reduced size-weight, long working life and better definition of the generated images. The increasing use of nanomaterials and nanostructures is demanding new tools with higher spatial resolving power for the investigation of objects and their properties in a fast and non-destructive manner. The proposed NANORAY technology can easily find applications in fluorescence spectrometry, aerospace, micro/nano mechanics, medical and archaeometric diagnostics, quality control in electronics and in the security field

Nanotechnology and textiles engineered by carbon nanotubes for the realization of advanced personal protective equipments

Carbon nanotubes (CNT) and CNT-based active materials have been used to assemble the gas sensing unit of innovative platforms able to detect toxic atmospheres developing in confined workplaces. The main goal of the project was to realize a full-featured, operator-friendly safety detection and monitoring system based on multifunctional textiles nanotechnologies. The fabricated sensing platform consists of a multiple gas detector coupled with a specifically designed telecommunication infrastructure. The portable device, totally integrated in the workwear, offers several advantages over the conventional safety tools employed in industrial work activities