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The concept of terroir is widely used in the wine industry, and many studies are undertaken to better understand the influence of local terrain features on produced wines. In this context, this study monitored nine Chardonnay plots in the Fruili wine region of Italy to gather information on grapevine growth and berry ripening. The study objective was to define viticulture potentialities allowing to identify future strategies for the production of a “single vineyard” Chardonnay wine at the Vie di Romans estate, Italy. During the growing season of 2017, relations were studied between terrain features and field observations on vine phenology and grape ripening. Stem water potential and gas exchange measurements were also effectuated. Results show that there are significant differences between the studied plots. Earliness of the grapevine cycle between the plots has been less evident to determine than the variation in berry characteristics. The latter were linked with identified pedoclimatic units, but the effect of the cultural practices should not be overlooked. The study should be perceived as a first monitoring campaign, highlighting the important differences between study plots. Further investigation in the following seasons should give a more accurate perception of individual plot characteristics and their impacts.

In this paper, we present selected results to discuss the 1D Mott localization observed in organic conductors and its influence on the nature of the low temperature magnetic ground state. The approach is essentially experimental and gives an occasion to summarize the work made in Bordeaux during the last twenty years. We first briefly describe the main results concerning the TMTTF salts. Then, we focus the discussion on materials presenting uniform organic stacks to emphasize the relevance of 1/4-Umklapp scattering. Results concerning DMtTTF salts are first described, next the example of the recently studied (EDT-TTF-CONMe 2 ) 2 AsF 6 is developed. In both cases, a low T antiferromagnetic ground state is observed, which suggests that the unified phase diagram proposed for the TMTXF series should be generalized, taking into account a progressive loss of centro-symmetry. We finally show how these arguments may rationalize older results found in the TMTTF series.

A systematic study of pseudoternary systems made of salted water, pentanol and SDS is presented for salt concentrations ranging from 20 to 80 g/l of NaCl. In the dilute part of the phase diagram, the system with the lowest salt concentration is known to present a continuous phase transition between phases of randomly interbonnected membranes, namely a sponge (symmetric) and an asymmetric phase. The same topology is found as the salt concentration is increased and the evolution of the characteristics of teh symmetric-asymmetric phase transition is studied. Light scattering experiments are first described. We show that the scattered intensity should be analysed in terms of a product of a structure and a form factor. The latter contribution gives directly the geometrical size of the phase (the mean distance between the membranes) without using any thermodynamical model and therefore gives an unambiguous location of the symmetric-asymmetric phase transition. The structure factor gives the critical behaviour at the phase transition. Electrical conductivity as a function of the frequency (in the range 100 Hz-15 MHz) has also been measured for the first time in this kind of systems. These phases can be considered as composites of a conducting solvent and a dielectric membrane and the data are analysed in terms of a low frequency (DC) conductivity leading to an «obstruction» factor and a dielectric constant strongly dependent on the frequency. Far from the S/A phase transition, the obstruction factor is constant and the dielectric constant shows a single Debye-like relaxation. Simple scaling laws are found for the variation of the intensity and of the frequency as a function of dilution. This indicates that the mode probes the «local structure» of the sponge phase. Near the S/A phase transition, in addition to this mode, another dielectric relaxation is observed at lower frequencies. At the same time, a departure from the scaling laws of the Debye mode and an increase of the obstruction factor can be interpreted as evidence for defects (holes?) on the membrane. We show that the role of these defects increases as the salt concentration decreases

The conductivity of ternary composites (carbon fibers, carbon spheres and polymer) is presented. A transition from an insultating to a conducting regime is observed above a critical volume fraction of conducting particles. Near the threshold a power law dependence of the conductivity is found. Both results are analysed in the frame of the percolation theory. In particular the influence of the relative amount of fibers and spheres on the percolation threshold and on the critical exponent is discussed and quantitatively explained using simple geometrical arguments Nous presentons la conductivite de composites ternaires (fibres de carbone, spheres de carbone, polymere). Une transition metal-isolant est observee au-dessus d'une concentration critique en particules conductrices. Pres du seuil nous observons une dependance en loi de puissance de la conductivite. Ces deux resultats sont analyses dans le cadre de la theorie de la percolation. En particulier nous discutons l'influence de la proportion fibres-spheres sur le seuil de percolation et sur l'exposant critique observe a l'aide d'arguments geometriques simples

Description des interactions dans les phases liquide isotrope et cristal liquide des microemulsions. Un modele est utilise pour tenir compte des termes d'energie entropique, de courbure et d'interaction et on discute la stabilite relative des phases isotropes (microemulsion), lamellaire et hexagonale

The study of the frustrated SA free energy allows the theoretical understanding of the recently discovered SA antiphase, as two dimensional escape to incommensurate phases. The picture obtained agrees with X-ray experimental evidence. We further give the phase diagram between bilayer SA', incommensurate S Ai , and antiphase SA.

[(TMTSeF)1-x(TMTTF)x]2ClO4 alloys have been studied under pressure for pressures up to 18 kbar through resistivity measurements. On substitution of TMTSeF in the superconducting compound (TMTSeF)2ClO4 with TMTTF a low temperature metal-insulator (M-I) transition is found at ambient pressure; above some critical pressure, P c, the M-I transition is suppressed giving rise to a metallic state to the lowest temperatures considered in this study. The phase diagrams of the various alloys are of the same form although Pc increases with increasing TMTTF concentration. Superconductivity was not observed in any of these materials in the metallic high pressure regime.

The conducting and magnetic properties of three salts of the DMTTF series are described. Low temperature antiferromagnetic ground states are found for the three compounds. Depending on the anions the crystal organisation is either triclinic (as for the TMTTF salts) or monoclinic. As expected, the position of the magnetic axis is correlated to the crystal symmetry. Finally the origin of the magnetic phase is discussed using the same theoretical framework as for the related TMTTF salts Etude de la conductivite electrique et de la resonance antiferromagnetique de trois sels (ClO 4 , ReO 4 , AsF 6 ): observation d'un etat antiferromagnetique a basse temperature. Etude par diffraction de rayons X: selon l'anion, la maille cristalline est triclinique ou monoclinique. Position des axes magnetiques, fonction de la symetrie cristalline. Discussion de l'origine de la phase magnetique

From the comparison of the physical properties of the (TMTTF)2X salts (mainly X = BF4, ClO4, PF6 and Br), the role of the counterion ordering is discussed and the intrinsic behaviour of the TMTTF chains is evidenced. Then, a parallel is drawn with the properties of the selenium analogs of these salts.

The structural and electrical properties of different (TMTTF) 2 MF 6 compounds are described and the role of the anion size is investigated through the behaviour of the SbF 6 salt for which a critical increase of the resistivity occurs below 154 K. The effects of alloying (TMTTF) 2 SbF 6 with AsF 6 or PF 6 is also studied and we show that this electrical anomaly still exists for small amount of doping. Finally the existence of structural instabilities involving centrosymmetrical anions is briefly discussed Etude des proprietes structurales et electriques de ces sels ou l'on etudie le role de la taille de l'anion, a partir du comportement du sel de SbF 6 pour lequel un accroissement critique de resistivite est observe a 154 K. Effet du dopage de (TMTTF) 2 SbF 6 par AsF 6 ou PF 6 : l'anomalie de resistivite persiste aux faibles taux de dopage. Discussion de l'existence d'instabilites structurales impliquant des anions centrosymetriques