A simple and versatile method for statistical analysis of the electrical properties of individual double walled carbon nanotubes

Double-walled carbon nanotubes (DWNTs) are potential candidates for new generation of on chip interconnections due to their nearly metallic behaviour. For such large scale integration purpose it is mandatory to characterize their electrical properties in a statistical way. We thus propose a new methodology for characterizing in one step, the electrical properties of a large population of nanotubes. The method enables to obtain histograms of the conductance and maximum current density of individual nanoobjects

A simple and versatile micro contact printing method for generating carbon nanotubes patterns on various substrates

We present an optimized process for generating at low cost, patterns of carbon nanotubes (CNTs) on a large variety of substrates through a simple micro contact printing method. This method meets the requirements for the integration of CNTs into microdevices, for applications in microelectronics (interconnects), flexible electronics (printed conductive electrodes) and biodevices (biosensors and biosystems for regenerative medicine). We have optimized a new method for inking PolyDiMethylSiloxane (PDMS) stamps with CNTs that turned out to improve significantly the quality of the printed features over large surfaces. This inking step is performed by adapting a spray-coating process leading to a dense and homogeneous coating of the stamp with a thin layer of CNTs. The printing step is performed using a solvent mediation, allowing us to pattern this thin layer of CNTs onto various substrates by contact through a thin film of liquid. We demonstrate that this soft and rapid methodology can lead to the realization of CNTs patterns with versatile geometries onto various substrates at the micron scale. Examples of applications for CNTs interconnects and flexible electronics are rapidly shown

Multi-scale engineering for neuronal cell growth and differentiation

In this paper we investigate the role of micropatterning and molecular coating for cell culture and differentiation of neuronal cells (Neuro2a cell line) on a polydimethylsiloxane substrate. We investigate arrays of micrometric grooves (line and space) capable to guide neurite along their axis. We demonstrate that pattern dimensions play a major role due to the deformation of the cell occasioned by grooves narrower than typical cell dimension. A technological compromise for optimizing cell density, differentiation rate and neurite alignment has been obtained for 20 lm wide grooves which is a dimension comparable with the average cell dimension. This topographical engineered pattern combined with double-wall carbon nanotubes coating enabled us to obtain adherent cell densities in the order of 104 cells/cm2 and a differentiation rate close to 100%

Schéma de niveaux de 223Ra II. Spectre d'électrons de conversion interne émis dans la désintégration 227Th → 223Ra

Cet article expose l'ensemble de nos études sur les quelques 300 raies de conversion du spectre d'électrons émis dans la désintégration 227 Th → 223Ra : étude par spectrométrie à focalisation semi-circulaire et à double focalisation, ce qui a permis de fixer toutes les intensités en valeur absolue par désintégration α et de fournir un grand nombre de multipolarités

Part-of relations, functionality and dependence

International audienceThat language hosts a multiplicity of part-whole relations is largely accepted, but no complete formal account is currently available. We first show how most distinctions between part-whole relations can be explained by considering the ontological categories of the arguments. We then focus on "component-integral whole" (CIW), a most important but formally little-studied relation. The analysis of the functional concepts involved leads us to introduce lexical categories and to characterize a notion of functional dependence. On this basis, four cases of CIW are distinguished and formally defined. The contrastive acceptability of determinative compound nouns shows the linguistic relevance of these distinctions. Lastly, we show how the definitions provide a simple solution to the elusive issue of variable transitivity patterns

A three-level approach to the semantics of space

This paper proposes some formal tools for representing the semantic content of French expressions referring to space. These tools consist of first, a relational –or qualitative– geometry encompassing topology, distance notions and projective geometry, as well as temporal notions, thus constituting a rather complete theory of naive space-time; and second, several formalisms to deal with functional aspects of entities such as intrinsic orientation, internal structure and categorizing; more generally, it is claimed that a representation in three levels (geometric, functional and pragmatic) is required to account for spatial expressions' semantics. To analyze the semantics of some of these expressions, this work systematically looks for valid reasoning schemata involving them; this approach also enables the testing of the proposed formal system as well as the evaluation of the definitions obtained for the studied lexemes

Distributional analysis of copredication: towards distinguishing systematic polysemy from coercion

National audienceIn this paper we argue that the account of the notion of complex type based on copredication tests is problematic,because copredication is possible,albeit less frequent, also with expressions which exhibit polysemy due to coercion.We show through a distributional and lexico-syntactic pattern-based corpus analysis that the variability of copredication contexts is the key to distinguish complex types nouns from nouns subject to coercion

DESCRIPTIONS VIBRATIONNELLES DE 193Au ET 195Au

Vingt-deux niveaux analogues de 193Au et 195Au sont décrits de façon satisfaisante par le modèle de Kisslinger-Sorensen et, avec plus de précision, par le modèle d'Alaga. L'accord entre les spectres de niveaux expérimentaux et les spectres théoriques prévus par ces modèles vibrationnels à couplage intermédiaire est meilleur que dans le modèle particule-rotor asymétrique développé par Meyer-ter-Vehn