NDEC: A NEA platform for nuclear data testing, verification and benchmarking

The selection, testing, verification and benchmarking of evaluated nuclear data consists, in practice, in putting an evaluated file through a number of checking steps where different computational codes verify that the file and the data it contains complies with different requirements. These requirements range from format compliance to good performance in application cases, while at the same time physical constraints and the agreement with experimental data are verified. At NEA, the NDEC (Nuclear Data Evaluation Cycle) platform aims at providing, in a user friendly interface, a thorough diagnose of the quality of a submitted evaluated nuclear data file. Such diagnose is based on the results of different computational codes and routines which carry out the mentioned verifications, tests and checks. NDEC also searches synergies with other existing NEA tools and databases, such as JANIS, DICE or NDaST, including them into its working scheme. Hence, this paper presents NDEC, its current development status and its usage in the JEFF nuclear data project

Achieving saturation in vertical organic transistors for organic light-emitting diode driving by nanorod channel geometric control

When conventional field-effect transistors with short channel length suffer from non-saturated output characteristics, this work proposed a vertical channel transistor to operate like a solid-state vacuum tube and exhibit good saturated curves. We utilized deep ultra-violet interference lithography to produce ordered grid-like metal to control the potential profile in vertical channel. We compared experimental and simulated characteristics to investigate the keys to achieve saturation. Finally, with an optimized design, a vertical organic transistor is used to drive a solution-processed white-light organic light-emitting diode to perform a luminescence control (0-260 cd/m(2)) with a 3.3-V base potential swing. (C) 2013 AIP Publishing LLC. [10.1063/1.4802999

Rapid Prototyping of Polymeric Nanopillars by 3D Direct Laser Writing for Controlling Cell Behavior

Mammalian cells have been widely shown to respond to nano-and microtopography that mimics the extracellular matrix. Synthetic nano-and micron-sized structures are therefore of great interest in the field of tissue engineering, where polymers are particularly attractive due to excellent biocompatibility and versatile fabrication methods. Ordered arrays of polymeric pillars provide a controlled topographical environment to study and manipulate cells, but processing methods are typically either optimized for the nano-or microscale. Here, we demonstrate polymeric nanopillar (NP) fabrication using 3D direct laser writing (3D DLW), which offers a rapid prototyping across both size regimes. The NPs are interfaced with NIH3T3 cells and the effect of tuning geometrical parameters of the NP array is investigated. Cells are found to adhere on a wide range of geometries, but the interface depends on NP density and length. The Cell Interface with Nanostructure Arrays (CINA) model is successfully extended to predict the type of interface formed on different NP geometries, which is found to correlate with the efficiency of cell alignment along the NPs. The combination of the CINA model with the highly versatile 3D DLW fabrication thus holds the promise of improved design of polymeric NP arrays for controlling cell growth

Towards a More Complete and Accurate Experimental Nuclear Reaction Data Library (EXFOR): International Collaboration Between Nuclear Reaction Data Centres (NRDC)

The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear Data Section (NDS) is successfully collaborating in the maintenance and development of the EXFOR library. As the scope of published data expands (e.g., to higher energy, to heavier projectile) to meet the needs from the frontier of sciences and applications, it becomes nowadays a hard and challenging task to maintain both completeness and accuracy of the whole EXFOR library. The paper describes evolution of the library with highlights on recent developments.Comment: 4 pages, 2 figure

Polarization-dependent fluorescence from an anisotropic gold/polymer hybrid nano-emitter

Based on nanoscale photopolymerization triggered by the dipolar surface plasmon mode, we developed a light-emitting gold nanoparticle/Eosin Y-doped polymer hybrid nanostructure. Due to the anisotropic spatial distribution of the dipolar surface plasmon mode during photopolymerization, this nano-emitter is anisotropic in both geometry and emission. The trapped dye molecules in the hybrid nanostructure display fluorescence intensity that is dependent upon the polarization of the incident excitation light. This nano-emitter further allows the photo-selection of fluorescence configuration (i.e., molecule concentration and refractive index of active medium) by controlling the incident polarization. (C) 2014 AIP Publishing LLC

Deep ultraviolet laser direct write for patterning sol-gel InGaZnO semiconducting micro/nanowires and improving field-effect mobility

Deep-UV (DUV) laser was used to directly write indium-gallium-zinc-oxide (IGZO) precursor solution and form micro and nanoscale patterns. The directional DUV laser beam avoids the substrate heating and suppresses the diffraction effect. A IGZO precursor solution was also developed to fulfill the requirements for direct photopatterning and for achieving semi-conducting properties with thermal annealing at moderate temperature. The DUV-induced crosslinking of the starting material allows direct write of semi-conducting channels in thin-film transistors but also it improves the field-effect mobility and surface roughness. Material analysis has been carried out by XPS, FTIR, spectroscopic ellipsometry and AFM and the effect of DUV on the final material structure is discussed. The DUV irradiation step results in photolysis and a partial condensation of the inorganic network that freezes the sol-gel layer in a homogeneous distribution, lowering possibilities of thermally induced reorganization at the atomic scale. Laser irradiation allows high-resolution photopatterning and high-enough field-effect mobility, which enables the easy fabrication of oxide nanowires for applications in solar cell, display, flexible electronics, and biomedical sensors

An electrochromic ionic liquid: design, characterisation and performance in a solid state platform

This work describes the synthesis and characteristics of a novel electrochromic ionic liquid (IL) based on a phosphonium core tethered to a viologen moiety. When integrated into a solid-state electrochromic platform, the viologen modified IL behaved as both the electrolyte and the electrochromic material. Platform fabrication was achieved through in situ photo-polymerisation and encapsulation of this novel IL within a hybrid sol-gel. Important parameters of the platform performance, including its coloration efficiency, switching kinetics and optical properties were characterised using UV/Vis spectroscopy and cyclic voltammetry in tandem. The electrochromic platform exhibits a coloration efficiency of 10.72 cm2C-1, and a varied optical output as a function of the incident current. Despite the rather viscous nature of the material, the platform exhibited approximately two orders of magnitude faster switching kinetics (221 seconds to reach 95 % absorbance) when compared to previously reported electrochromic ILs (18,000 seconds)

Fabrication of refractive microlens arrays by visible irradiation of acrylic monomers: influence of photonic parameters

The fabrication of refractive microlenses with self-developing photopolymers is reported. A spatially controlled illumination of the photosensitive layer induced an inhomogeneous photopolymerization involving formation of 3-D polymer network, mass-transport process of reactive species and bending of the surface. The process exhibited a completely self-processing character without any chemical post-treatment to reveal the relief. The lens arrays displayed diameters ranging from less than 100 μm to 1 mm and focal lengths from 100 μm to a few millimeters, depending on photonic, optical and physico-chemical parameters. The paper focuses on the importance of photonic parameters in the generation of microlens arrays and discusses the flexibility of this technique in the visible range

Flexible and Ultra-thin Metal-Oxide films for multi resonance-based Sensors in Plastic Optical Fibers

International audienceWe have exploited a laser-based integration process of ultra-thin Metal-Oxide (MO) films in order to improve the plasmonic effect in sensors based on D-shaped Plastic Optical Fibers (POFs). More specifically, by using ultra-thin MO films, the performances of the Surface Plasmon Resonance (SPR) phenomenon improve and a Lossy Mode Resonance (LMR) can occur. Although the role of this kind of materials has been already presented, when they are deposited as overlayer (upside the thin metal film), we have used a different approach by depositing MOs, specially Zirconium Oxide (ZrO 2) and Titanium Oxide (TiO 2), as flexible intermediate layers between the exposed core of POFs and the gold film. The MO layer is prepared from sol-gel solution and Deep-UV laser curing allows to densify the thin film and tune the refractive index, with a room temperature process fully compatible with the flexible polymer substrates. In a preliminary step, we have carried out numerical results, based on transfer matrix formalism, in order to predict the SPR response. Subsequently, we have experimentally characterized the developed sensor configurations. Numerical and experimental results have shown above all an enhancement of the sensor performances, in terms of SPR sensitivity, with respect to a reference sensor based on a polymer instead of MOs. Moreover, in some proposed sensor configurations, together with the SPR phenomenon, an LMR phenomenon was observed. It occured in a different wavelength range, for a typical refractive index range present when considering receptors for biochemical sensing applications. Therefore, both resonances (SPR and LMR) could be used in several application fields

Flexible and Ultra-thin Metal-Oxide films for multi resonance-based Sensors in Plastic Optical Fibers

International audienceWe have exploited a laser-based integration process of ultra-thin Metal-Oxide (MO) films in order to improve the plasmonic effect in sensors based on D-shaped Plastic Optical Fibers (POFs). More specifically, by using ultra-thin MO films, the performances of the Surface Plasmon Resonance (SPR) phenomenon improve and a Lossy Mode Resonance (LMR) can occur. Although the role of this kind of materials has been already presented, when they are deposited as overlayer (upside the thin metal film), we have used a different approach by depositing MOs, specially Zirconium Oxide (ZrO 2) and Titanium Oxide (TiO 2), as flexible intermediate layers between the exposed core of POFs and the gold film. The MO layer is prepared from sol-gel solution and Deep-UV laser curing allows to densify the thin film and tune the refractive index, with a room temperature process fully compatible with the flexible polymer substrates. In a preliminary step, we have carried out numerical results, based on transfer matrix formalism, in order to predict the SPR response. Subsequently, we have experimentally characterized the developed sensor configurations. Numerical and experimental results have shown above all an enhancement of the sensor performances, in terms of SPR sensitivity, with respect to a reference sensor based on a polymer instead of MOs. Moreover, in some proposed sensor configurations, together with the SPR phenomenon, an LMR phenomenon was observed. It occured in a different wavelength range, for a typical refractive index range present when considering receptors for biochemical sensing applications. Therefore, both resonances (SPR and LMR) could be used in several application fields