SMOS-NEXT: A New Concept for Soil Moisture Retrieval from Passive Interferometric Observations

This book is a collection of 19 articles which reflect the courses given at the Collège de France/Summer school “Reconstruction d'images − Applications astrophysiques“ held in Nice and Fréjus, France, from June 18 to 22, 2012. The articles presented in this volume address emerging concepts and methods that are useful in the complex process of improving our knowledge of the celestial objects, including Earth

Plasma etching of organic material: Combined effects of charged and neutral species

A model organic material, namely the 36-n-alkane hexatriacontane, was etched in a dissymmetrical parallel plate RF plasma reactor and a dual distributed electron cyclotron resonance (DECR) plasma reactor, in different O2-Ar mixtures. A specific attention was paid to the role of the ion bombardment, especially when its effect is combined with the chemically active species created in an oxygen discharge. The discharge was monitored by optical emission spectroscopy (OES). The modifications induced by plasma treatment on the structure of the material were analysed by Fourier transform infrared spectroscopy (FTIR), steric exclusion chromatography (SEC) and composition analysis. We found that the ion bombardment has not only a sputtering effect but also enhances the reaction rate of the chemical species on the layer surface. It appears that plasma treatment leads to cross-linking and recombination with molecules from the room atmosphere

Characterization of polypropylene surface treated in a CO2 plasma

The polypropylene modification in CO2 plasma mainly contributes to degradation, functionalization, and cross-linking. The degradation, whose rate is depending on CO2 dissociation and oxygen atom formation, is a quite slow reaction and it is associated with surface topography alteration, especially of the amorphous phase of the polypropylene. The surface roughness increases with the treatment duration and the amorphous phase is more degraded than the crystallized part. The functionalization, corresponding to an increase of the surface energy (57.3 mJ.m(-2) in 30 s), and to an oxidation (23 oxygen at.%) with the appearance of alcohol, ketone, and acid functions is a much faster phenomenon. Cross-linking takes also place during this type of treatment and will reinforce the stability of the modified surface

New surfaces with hydrophilic/hydrophobic characteristics in relation to (no)bioadhesion

The possibility of biosurfaces with high or low adhesiveness for protein, bacteria or eukaryotic cells is discussed. At the interface surface object/biological milieu, biocompatibility, (no) bioadhesion and (no) biocontamination are shown to be correlated with physico-chemical surface characteristics. First consequence is the (no) possibility of biofilm formation. Substrates with low surface energy could interact only with hydrophobic biomolecules. On substrates with high surface energy, a water monolayer spontaneously formed. Modification of a surface by plasma techniques is a way for engineering biomaterials. Plasma techniques are dry processes and more suitable for biomedical applications. In the field of biomaterial medical devices, in hygienic prevention of nosocomial diseases, in food packaging, the use of substrates with a very hydrophilic character may help to prevent the proliferation of cells and bacteria. Such a technique is so efficient that antibiotic molecules are not necessary. Therefore, surface engineering is a tool for modifying and adapting materials to specific biological applications

PANI/ZnO/Quartz structure for Love wave gas sensor

Everyone knows the importance of sensors in our society and the huge attempt to improve their properties in order to obtain better sensitivity and selectivity. In this paper, we are more particularly focused on gas sensors based on surface acoustic waves (SAW) device. In a previous work, we have developed and studied a structure composed of a 90° rotated ST quartz crystal covered with a ZnO layer. By developing inter-digital transducers (IDT) on this structure, we can generate different types of acoustic waves. Love waves which are confined near the surface are known to be very sensitives to fluids (liquids or gases). The aim of this work is to present the way we have developed this optimal structure and to test it with a specific polymer. This polymer is polyaniline (PANI). Its main advantage is that it should be deposited by cold pulsed plasma process

Azobenzene-Containing Monolayer with Photoswitchable Wettability

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