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Intrahepatic cholangiocarcinoma is a rare disease with a poor prognosis. In patients where surgical resection is possible, outcome is influenced by perioperative morbidity and lymph node status. Laparoscopic liver resection is associated with improved clinical and oncological outcomes in primary and metastatic liver cancer compared with open liver resection, but evidence on intrahepatic cholangiocarcinoma is still insufficient. The primary aim of this study was to compare overall survival for a large series of patients treated for intrahepatic cholangiocarcinoma by open or laparoscopic approach. Secondary objectives were to compare disease-free survival, predictors of death, and recurrence.Patients treated with laparoscopic or open liver resection for intrahepatic cholangiocarcinoma from 2000 to 2018 from 3 large international databases were analyzed retrospectively. Each patient in the laparoscopic resection group (case) was matched with 1 open resection control (1:1 ratio), through a propensity score calculated on clinically relevant preoperative covariates. Overall and disease-free survival were compared between the matched groups. Predictors of mortality and recurrence were analyzed with Cox regression, and the Textbook Outcomes were described.During the study period, 855 patients met the inclusion criteria (open liver resection = 709, 82.9%; laparoscopic liver resection = 146, 17.1%). Two groups of 89 patients each were analyzed after propensity score matching, with no significant difference regarding pre- and postoperative variables. Overall survival at 1, 3, and 5 years was 92%, 75%, and 63% in the laparoscopic liver resection group versus 92%, 58%, and 49% in the open liver resection group (P = .0043). Adjusted Cox regression revealed severe postoperative complications (hazard ratio: 10.5, 95% confidence interval [1.01-109] P = .049) and steatosis (hazard ratio: 13.8, 95% confidence interval [1.23-154] P = .033) as predictors of death, and transfusion (hazard ratio: 19.2, 95% confidence interval [4.04-91.4] P.001) and severe postoperative complications (hazard ratio: 4.07, 95% confidence interval [1.15-14.4] P = .030) as predictors of recurrence.The survival advantage of laparoscopic liver resection over open liver resection for intrahepatic cholangiocarcinoma is equivocal, given historical bias and missing data.

International audience; Imiter, the silver mine of the Moroccan Anti-Atlas still in operation today, displays archaeological evidence of ancient mining and metallurgical works. Written sources and the study of artefacts has already allowed to suggest that the site of Imiter was the ancient Todgha, a locality mentioned during the medieval period (El Ajlaoui 1994). Between 2011 and 2014, a multidisciplinary team (historian, metallogenic geologist, geochemist, archaeologists) undertook surface and underground prospection, the excavation of three ore enrichment tanks as well as the mineralogical and geochemical characterization of ancient ores and metallurgical wastes. The radiocarbon dates obtained on the tanks place their final use between the 2nd century cal BC and the 5th century cal AD, i.e. before the Islamic period. This article reports on results of this research, which documents for the first time an ancient silver mining site in the southern regions of Morocco, which continued in medieval times.; Imiter, mine d’argent de l’Anti-Atlas marocain encore en activité, possède des vestiges archéologiques de travaux miniers et métallurgiques. L’étude de textes anciens et d’artefacts a permis de la rapprocher de la mine d’argent de Todgha connue à l’époque médiévale (El Ajlaoui 1994). Entre 2011 et 2014, une équipe pluridisciplinaire (historien, géologue métallogéniste, géochimiste, archéologues) a entrepris des prospections en surface et en souterrain, la fouille de trois cuves de traitement du minerai ainsi que la caractérisation minéralogique et géochimique de minerais et déchets métallurgiques anciens. Les résultats des datations des cuves placent le dépôt après utilisation entre le IIe siècle cal BC et le Ve siècle cal AD, soit avant la période islamique. Cet article fait état des résultats de ces recherches, qui documentent pour la première fois une exploitation antique de l’argent dans les régions méridionales du Maroc, exploitation qui s’est poursuivie à l’époque médiévale.

Dans le cadre du programme ANR Archeostraits, une cartographie de l'habitat du site archeologique de la Silla del Papa (sud de l'Espagne) a ete entreprise. Elle est rendue complexe par la topographie combinant de forts deniveles et une vegetation persistante. De plus, les bâtiments de la fin de l'âge du fer sont ancres a plusieurs niveaux dans les parois de barres rocheuses, ce qui rend inoperante une analyse architecturale traditionnelle a partir de planimetries en 2D. L'analyse 3D a plusieurs echelles, de l'environnement au sondage, demande une adaptation des outils d'acquisition 3D a cet espace. Trois technologies presentes au sein du laboratoire Traces generant des nuages de points denses ont ete utilisees.

International audience

International audience; Ce livre fait suite à Martys 1, paru en 1993 (référence 8761, épuisé). Il concerne les débuts (Ier s. a.C.) du grand centre sidérurgique romain situé dans le domaine des Forges (Les Martys, Aude), au cœur de la Montagne Noire. La première partie présente les résultats des dernières fouilles archéologiques (1988-1995) exécutées dans deux sites majeurs du domaine : d'une part, Monrouch, un secteur en grande partie conservé intact depuis l'Antiquité, et dont la fouille a mis au jour une batterie de six bas fourneaux de réduction du type classique des Martys, encore pourvus, au moins partiellement, de leur système de ventilation, ainsi qu'une construction annexe, en bois et en terre ; d'autre part, le Grand Ferrier, qui, progressivement détruit par l'exploitation moderne des scories, n'offrait plus à la fouille que de rares lambeaux de terrain encore en place : on y a découvert, outre plusieurs foyers d'épuration, un ensemble désordonné de bas fourneaux, parmi lesquels un unique exemplaire de petit module, dont on a essayé de comprendre la signification face à plusieurs autres du type classique. L'étude des mobiliers (céramiques, amphores, monnaies) a permis de distinguer les phases successives de ces premiers moments du site et montré l'enracinement de la communauté des sidérurgistes dans la culture italique. Enfin les prospections effectuées autour des Martys ont révélé une forte densité d'ateliers sidérurgiques, dont l'organisation et la production font l'objet d'hypothèses. La deuxième partie est consacrée à l'archéométrie. Recueillis au cours des fouilles, quelques objets en fer et de nombreux échantillons (minerais, scories, déchets divers, éléments de bas fourneaux, sols d'ateliers, etc.) ont été examinés en laboratoire, à l'aide de techniques souvent de pointe. En particulier la caractérisation chimique du fer des Martys a conduit les archéomètres à identifier la présence de ce fer dans les cargaisons de plusieurs épaves (Ier s. a.C. et Ier s. p.C.) au large des Saintes-Maries-de-la-Mer, apportant ainsi de solides arguments à la réalité de sa diffusion. La troisième partie constitue le compte rendu des expérimentations, dont l'objectif était de comprendre par la pratique comment fonctionnaient ateliers et bas fourneaux, afin de pouvoir un jour fabriquer du fer dans les conditions d'il y a 2 000 ans, et justifier ainsi une production évaluée à 110 000 tonnes pendant trois siècles.

Las investigaciones en curso en el yacimiento de la Silla del Papa (Tarifa, Cádiz) han revelado la existencia de un núcleo urbano de gran entidad, ubicado en la cima de la Sierra de la Plata. Esta ciudad, la primera Baelo, se trasladó hacia la costa a principios del reinado de Augusto. Las excavaciones realizadas en 2014-2016 han permitido fijar con más precisión la fecha de su abandono, entre 40 y 20 a. C., estudiar el urbanismo de la ciudad de época republicana, que está caracterizado por casas de varios pisos adosadas a paredes de roca, y descubrir una necrópolis de incineración utilizada entre finales del siglo III a. C. y finales del i a. C., sin paralelos en la Bética, con dos tipos de monumentos: tumulares y turriformes. Les recherches en cours sur le site de la Silla del Papa (Tarifa) ont révélé l’existence d’une agglomération urbaine de grande ampleur située au sommet de la Sierra de la Plata. Cette ville, la première Baelo, fut transférée sur la côte au début du règne d’Auguste. Les fouilles en cours depuis 2014 ont permis de fixer plus précisément la date de l’abandon du site de hauteur, entre 40 et 20 av. J.-C. Dans le siècle qui précède cet abandon, la Silla del Papa présente un urbanisme dense avec des maisons à plusieurs étages adossées aux parois rocheuses. A également été mise au jour une nécropole à incinération utilisée entre la fin du IIIe siècle et la fin du ier siècle av. J.-C, sans parallèles connus en Andalousie, avec deux types de monuments: tumulaires et turriformes. La Silla del Papa: hábitat y necrópolis https://journals.openedition.org/mcv/7333 2/23 The ongoing investigations at the Silla del Papa site (Tarifa, Cádiz) have uncovered a large urban nucleus, located at the summit of Sierra de la Plata. This town, the original Baelo, was transferred to the coast early in the reign of Augustus. The excavations carried out in 2014-2016 have made it possible to fix the date of its abandonment more precisely, at between 40 and 20 BCE, to examine the layout of the town from the Republican era, which is characterised by multi-storeyed houses backing onto rock, and to uncover a crematorium used between the end of the 3rd century BCE until the end of the 1st century BCE, unique in Baetia, with two types of monuments: tumular and turriform.

The synthesis of functionalized unsymmetrically substituted tetrathiafulvalenes 1, 2 and 3, 4 (see scheme in the introduction) was described. Two routes were used. A cross-coupling preparation from appropriate 1,3-dithiolium salts which offered poor yields and a WITTIG-HORNER type reaction which was studied in details. A solvent modification in the later reaction, allowed us to improve the yield of 1 and 2 obtained selectively.

Different methylated tetrathiafulvalenecarboxylic acids are synthesized by a two or three steps procedure. The methylated tetrathiafulvalene species is lithiated using an equimolar amount of n-BuLi at −80°C. The lithiated compound is then either carbonated producing new acids 2 to 4, or treated with methylchloroformiate. The monoesters 9, 11 and 13 obtained are easily characterized by mass spectroscopy and then converted into acids 2 to 4 by saponification. New diesters 10 and 12 are also synthetized and characterized.

We propose an improved general method for the synthesis of tetrathiafulvalene and its methylated derivatives. TTF is obtained in a five steps preparation offering a high Overall yield. Concerning the unsymmetrically methylated tetrathiafulvalenes, four different procedures are analysed. It is shown the best routes to prepare trimethyltetrathiafulvalene are a WITTIG type reaction, and a selective synthesis based on a WITTIG-HORNER reaction. The monomethyltetrathiafulvalene has been isolated in a 96% state of purity.

L’article reunit les contributions de quatorze chercheurs, specialistes de secteurs les plus divers de l’archeologie africaine (industries paleolithiques, neolithisation, histoire de l’elevage, art rupestre, emergence des societes complexes, metallurgie du Fer, amenagements des terroirs …), autour de sujets concernant des regions tres contrastees et dispersees sur l’ensemble du continent (Afrique du sud, Afrique de l’est, Afrique de l’ouest, Sahara, Maghreb). Le parti pris d’axer la reflexion generale sur l’etude de la variabilite des conditions socio-economiques rencontrees dans le temps et dans l’espace en assurent la coherence. Au travers de la prise en compte des elements constituant cette etonnante mosaique, il s’agit de s’interroger sur la nature des reponses apportees par les groupes humains confrontes aux diverses sollicitations de leurs environnements (pression des milieux naturels, relations socio-economiques, cadres culturels et historiques …). L’Afrique consideree au travers de ces diverses facettes devient donc, pour les auteurs, le laboratoire de reflexion majeur pour l’etablissement d’une documentation fiable relative au probleme crucial de la complexite des relations entre l’Homme et son environnement.

A new bis-TTF donor (TTF is tetrathiafulvalene) containing a pyridine diester spacer, namely bis{2-[(6,7-tetramethylene-3-methylsulfanyltetrathiafulvalen-2-yl)sulfanyl]ethyl} pyridine-2,6-dicarboxylate-tetracyanoquinodimethane-dichloromethane (2/1/2), 2C(33)H(33)NO(4)S(12) x C(12)H(4)N(4) x 2 CH(2)Cl(2), has been synthesized and its electron-donating ability determined by cyclic voltammetry. The electrical conductivity and crystal structure of this donor-acceptor (DA) complex with TCNQ (tetracyanoquinodimethane) as the acceptor are presented. The TCNQ moiety lies across a crystallographic inversion centre. In the crystal structure, TTF and TCNQ entities are arranged in alternate stacks; this feature, together with the bond lengths of the TCNQ molecule, suggest that the expected charge transfer has not occurred and that the D and A entities are in the neutral state, in agreement with the poor conductivity of the material (sigma(RT) = 2 x 10(-6) S cm(-1)).

Les recherches engagees depuis 2007 sur le site de la Silla del Papa (Tarifa, province de Cadix, Espagne) ont mis au jour une importante agglomeration perchee, probable berceau de la communaute d'origine bastulo-punique qui fonda, sous Auguste, la ville de Baelo. Ce site de hauteur, occupe du Xe au Ier siecle av. J.-C., a livre de nombreux vestiges d'un urbanisme singulier, conditionne en partie par des contraintes topographiques.

Haut lieu de l’industrie minière et métallurgique espagnole à la fin du xixe siècle et pendant une partie du xxe, la Sierra de Carthagène n’est plus aujourd’hui qu’une gigantesque friche, éventrée par de grandes carrières à ciel ouvert, jalonnée d’imposantes haldes de déblais résultant de l’extraction, d’épais dépôts de stériles provenant du lavage du minerai, de vestiges d’installations minières et métallurgiques – puits et chevalets, fours de grillage –, et de bien d’autres bâtiments – lave...

Les fouilles de la Casa de Velazquez a Baelo Claudia ont fait connaitre une des villes romaines les mieux conservees d’Espagne, devenue une reference obligee pour tout ce qui concerne l’urbanisme et l’architecture des municipes du Haut Empire en Hispanie. Completees ces dernieres annees par les travaux du Conjunto Arqueologico de Baelo Claudia et de l’universite de Cadix, ces fouilles ont cependant laisse sans reponse la question des origines preromaines de la ville. La fondation de Baelo dat...

International audience; The paper presents a single-crystal ESR study of a series of pristine and X-ray irradiated (TMTTF)2X salts, where TMTTF is tetramethyltetrathiafulvalene and X is either a centro-symmetrical (SbF6 and Br) or a non-centro-symmetrical (ReO4, ClO4, BF4, SCN and NO3) monovalent anion. Besides standard line-width and spin-susceptibility measurements, the analysis of the asymmetry of the ESR line shape allows to obtain simultaneous information on the electrical conductivity. This whole set of data is used to determine the charge and spin gaps related to the charge ordering (CO) and anion ordering (AO) ground states and their evolution as a function of X-ray irradiation damages. We show in particular that the sensibility of (TMTTF)2X salts to irradiation depends upon the nature of the anion X and that the CO ground state is drastically affected by irradiation damages at the difference of the AO ground state. We also present evidence of a CO transition and of a decoupling between the AO transition and the opening of a spin gap in (TMTTF)2NO3.

The syntheses of seven new tetrathiafulvalene (TTF) derivatives substituted by two pyridine groups and their characterization by the usual methods are described. Cyclic voltammetry of all the compounds showed two one-electron reversible waves with redox potentials comparable to other pyridine-substituted TTF molecules. X-ray crystal structures were solved for five compounds. In all the molecular structures the pyridine groups lie out of the central TTF plane but are located on the same side of that plane.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

International audience; A sharp maximum in the temperature dependence of the relaxation time obtained from low-frequency permittivity measurements is found in the quasi-one-dimensional conductor at a temperature of 101. This maximum is associated with the second-order phase transition into a charge-ordered state of Wigner type. The character of relaxation processes above and below this phase transition is discussed.

We have measured the temperature dependences of the conductance G and the dielectric permittivity e ′ of the (TMTTF) 2 SbF 6 compound under a moderate pressure. The maximum of G ( T ) associated with the Mott–Hubbard localization disappears under pressure. With increasing pressure the peak in e ′( T ), corresponding to the charge ordering (CO) phase transition, shifts to lower temperatures and broadens. At pressures above 0.24 GPa, e ′( T ) becomes strongly frequency dependent. These modifications are explained in the frame of the extended Hubbard model and a slowing down behavior.

CETBz-TTF (4,5-bis(cyanoethylthio)benzo-tetrathiafulvalene) and CESBz-TTF (4,5-bis(cyanoethylseleno)benzo-tetrathiafulvalene) 5 have been synthesized from cyano precursor via a cross-coupling reaction. Radical salts with paramagnetic Cu(II) complex anions, such as (CETBz-TTF)2CuCl4 6 and (CESBz-TTF)2CuCl4 7 have been prepared. X-ray crystal structure and physical properties of these new compounds are presented.

We report the first extensive study of longitudinal (ρ a ) and transverse (ρ c ) transport properties versus temperature of the organic quasi one dimensional conductor TMTTF2PF6 over the pressure domain extending from ambient up to 26 kbar. The dimensional cross over observed around 14 kbar separates a 1D region dominated by the Mott-Hubbard gap with activated transport at low pressure from a 3D domain where the temperature range of the metallic behavior, extends up to room temperature along the chains and is progressively increased towards high temperatures in the c direction. In the 1D regime, the different activations obtained from ρ a (T) and ρ c (T) data suggest two different modes of conduction in the longitudinal and transverse directions.

The charge ordering observed in the (TMTTF) 2 X family has been studied by X-ray absorption spectroscopy. XANES measurements at the Sulfur K-edge show no evidence of charge disproportionation larger than 0.5 e, and EXAFS at the Phosphorus K-edge indicate no displacements of the PF 6 anion larger than 0.05 A. The difficulty to observe a structural signature of this charge ordering is due to the triclinic symmetry of these salts. By contrast, in the monoclinic charge transfer salt (DMtTTF) 2 ClO 4 , a screw axis symmetry constrains the molecular stacks to be uniform. In this real 1/4-filled system, charge localization is observed at about 150 K. We show that around this temperature an incommensurate modulation of reduced wave vector (0.58,0,-0.275) is stabilized. The transition is strongly hysteretic, but no long range order is established. We suggest that this modulation, which has the 4kF periodicity in the chain direction, stabilizes a local antiferroelectric state similar to the one previously observed in (TMTTF) 2 SCN.

Five new substituted tetrathiafulvalene derivatives containing the acetoxyphenyl group as a side-chain have been synthesized using a Wittig-type condensation. Four of them contain peripheral selenium atoms. From cyclic voltammetry data, the electron donor abilities of the obtained compounds have been found to be similar to that of BEDT-TTF. The crystal structures of three of these new donors have been determined. A series of radical cation salts derived from these donors has been obtained by electrocrystallization; the electrical conductivity of these phases measured on compressed powder pellets range from 5 × 10−4 to 4 × 10−5 S cm−1. Charge transfer complexes have also been chemically prepared by using TCNQ as an electron acceptor; the electrical conductivity of their compressed powders range from 0.3 to 0.5 S cm−1. The crystal structure of one of these charge transfer complexes has been determined and shows that the donor and the acceptor entities form regular segregated stacks; its rather high conductivity, actually measured on powder, is in agreement with this structural feature.

New TTF precursors for the construction of conducting and magnetic materials have been synthesized by using the palladium-catalyzed cross-coupling reaction between a mono- or a bis(trialkylstannyl)tetrathiafulvalene and a series of heteroaryl halides. The redox potential and some crystallographic data of these new building blocks are presented and discussed.

Within the generic (pressure, temperature) phase diagram of (TM) 2 X compounds, we have investigated the crossover between the spin density wave and superconducting ground states by transport measurements under pressure. Superconductivity is reported for the first time in (TMTTF) 2 BF 4 below 1.38 K, in the pressure range 33.5–37.5 kbar, and coexists with the spin density wave phase, present alone at lower pressure. Differential resistance measurements support the idea of a phase segregation with the proportion of the superconducting phase (related to the measured critical current) increasing with pressure.

The synthesis of singly and doubly bridged bis-TTF containing a 2,6-bis(methylthio)pyridine group as a linker and potentially usable as a ligand for paramagnetic transition metal complexes is reported. Cyclisation leading to doubly bridged bis-TTF has been achieved without using the high dilution technique generally employed in such cases. The redox behaviour of such precursors has been studied by cyclic voltammetry and square wave techniques. The crystal structure of one of these electron donors has been determined by X-ray diffraction showing a stacking arrangement of the TTF units.

The synthesis of series of tris- and tetrakis-tetrathiafulvalene (TTF) has been carried out by using complementary routes involving deprotection-alkylation methods of mono or dithiolates. The electron donor ability of these new compounds has been measured by cyclic voltammetry (CV) and the square wave (SQW) technique. All the products exhibit a donating power similar to those found for TTF derivatives such as TMTTF and BEDT-TTF known to lead to conducting salts. Most of these donors have been converted by galvanostatic electrosynthesis into perchlorate and hexafluorophosphate salts. These salts have been found semi-conducting.

A detailed thermodynamical investigation of the quasi-one-dimensional sulphur-based organic salts (TMTTF)2PF6 and (TMTTF)2Br is presented in the temperature range from 30 mK to 7 K. In this part (part I), we consider the general aspects of the low-temperature specific heat of these materials in relationship with their ground states and we compare them with those previously measured for selenium members of the same family. All these compounds exhibit very similar thermodynamical behaviour, despite a variety of electronic ground states: spin-Peierls for (TMTTF)2PF6, commensurate antiferromagnetic spin modulation for (TMTTF)2Br, incommensurate spin-density wave for (TMTSF)2PF6 (TMTSF≡tetramethyltetraselenafulvalene). We show that the low-energy excitations which are predominant below 1 K have a similar character to that observed in glassy systems, at least on short timescales of measurements. The dynamical aspects of the non-equilibrium thermodynamics will be presented separately in the following part (part II).

Les etudes recentes sur les carrieres de marbre des Pyrenees se sont orientees dans trois directions : un travail de terrain (prospection et sondages) a des fins d'inventaire et d'etablissement d'une chronologie fiable fondee sur des donnees assurees ; une recherche scientifique de criteres d'identification des materiaux ; une analyse de la diffusion a partir de lots de mobilier issus de grands sites regionaux. Les travaux recents sur les objets en marbre typiques des vallees pyreneennes (autels votifs et auges cineraires) permettent de mesurer l'impact de l'economie du marbre sur la vie et la culture des populations montagnardes de l'Antiquite.

Conductivity and permittivity of the quasi-one-dimensionsional organic transfer salt $(\mathrm{TMTTF}{)}_{2}{\mathrm{PF}}_{6}$ have been measured at low frequencies ${(10}^{3}\char21{}{10}^{7}\mathrm{Hz})$ between room temperature down to below the temperature of transition into the spin-Peierls state. We interpret the huge real part of the dielectric permittivity (up to ${10}^{6})$ in the localized state as the realization in this compound of a charge ordered state of Wigner crystal type due to long-range Coulomb interaction.

Direct evidence of a new phase transition at TCO = 100.6 K in the organic quasi-one-dimensional (TMTTF)2AsF6 salt has been obtained from conductivity and dielectric permittivity measurements. This phase transition is assigned to a charge-ordered state (4kF charge density wave of Wigner type) due to charge-induced electron-electron interactions.

By using a chalcogenolate (thiolate or selenolate) protection–deprotection strategy, a series of singly bridged bis-TTFs, 3a–c, 4a, have been prepared in high yield (84–96%) through two different routes. Route 2, involving the reaction between a monochalcogenolate TTF derivative with a previously prepared monoiodinated TTF species, appears to be a very useful and general strategy to selectively prepare bis-TTFs in high yields (84–90%). The bis-TTFs, 3a–c, 4a, are easily converted into the corresponding dimethylated derivatives 3a′–c′, 4a′ in a basic (2 equiv.) IMe medium. The electron-donating ability of this series of bis-TTFs has been determined by cyclic voltammetry. Several salts, mainly perchlorates, of the donors 3a, 4a, 3a′–c′ have been obtained as black powders by galvanic electrosynthesis. Their room temperature electrical conductivity as compressed powder pellets has been measured, together with the temperature dependence of the ESR signal.

Les ferriers romains du domaine des Forges (Les Martys, Aude) sont aujourd'hui assez bien connus : chronologie (de 60/50 avant J.-C. a 260 environ apres J.-C.), volume de scories, production minimale de fer assuree (37 000 t), bas fourneaux et ateliers du Ier s. avant J.-C., etc. En 1998, une prospection menee au voisinage du domaine, dans le bassin superieur de la Dure, a eu pour but de situer ces vestiges dans leur contexte siderurgique. Elle a permis de reperer 33 ferriers, qui s'ajoutent aux 11 deja connus. La plupart d'entre eux sont surement d'epoque romaine, comme le montre le materiel qu'ils renferment (amphores Dressel 1 principalement et/ou sigillee). On remarque que l'activite du secteur s'est concentree, sans doute a partir de la fin du Ier s. avant J.-C., sur deux sites principaux, le Grand Ferrier des Forges et le ferrier de Laprade-Basse. Enfin, une estimation calculee du volume de tous ces ferriers represente un total de pres de 300 000 m3, ce qui correspond a une production d'environ 80 000 t de fer pendant un peu plus de trois siecles. Il est difficile d'interpreter historiquement ces donnees archeologiques. Peut-etre au Ier s. avant J.-C. le secteur etait-il aux mains d'une societe de publicains, comme invite a le penser une comparaison avec les mines de la haute vallee de l'Orb (Herault). Par la suite, cette concentration s'est maintenue, mais on ignore tout de son organisation.

Quatre annees de prospections et de sondages d'evaluation archeologique ont permis de dresser une carte des vestiges miniers et metallurgiques des Hautes Baronnies (Hautes-Pyrenees) et de demontrer l'existence d'une phase antique de l'exploitation du fer. L'analyse de la carte offre une image de l'organisation de l'exploitation. L'examen des donnees epigraphiques existantes prouve que ce secteur est bien le pagus ferrariensis de l'inscription d'Asque et ouvre des perspectives sur la condition des exploitants.

Unsymmetrically substituted tetrathiafulvalene derivatives containing hydroxy group(s) on side-chain(s) have been synthesized from cyano precursors via either a cross-coupling reaction or a Wittig-type condensation. As deduced from cyclic voltammetry data, the electron donor properties of the obtained compounds have been found to be similar to those of BEDTTTF. A series of radical cation salts derived from these donors has been obtained by electrocrystallization and charge transfer complexes have been prepared chemically by using TCNQ as an electron acceptor. The electrical conductivity of these phases ranges from 3 × 10−2 to 7 × 10−7 S cm−1 which is consistent with their structural features. X-Ray structural analysis of three of the radical cation salts with monovalent closed-shell anions (Br−, ClO4−) indicates a 1 ∶ 1 stoichiometry which implies that, in each case, the donor has been oxidized to the D+ state. In the same way, a crystal structure made of stacks where the donor and the acceptor molecules alternate has been found for a charge transfer complex between TCNQ and a donor derived from EDTTTF. The crystal structure of one of the donors indicates that the flexibility of the hydroxylated side chains appears as a favourable feature for the formation of hydrogen bonds.

We present a study, of the slow dynamics in the heat relaxation at very low temperature (T < 1 K) in the nominally commensurate SDW compound (TMTTF) 2 Br, that we compare to the incommensurate SDW-(TMTSF) 2 PF 6 . Instead of a broad distribution of relaxation times g(log τ) in the PF 6 salt, the dynamics in the Br salt reveals almost discrete bands in the relaxation spectrum. A saturation towards equilibrium is reached very rapidly (within ∼ 20 mn) at T ∼ 100 mK in comparison with PF 6 (more than 10 hr for the same temperature).

The scope and limitations of the synthesis of unsymmetrically substituted TTF derivatives via the “phosphonate way” was investigated using as precursors 1,3-dithiol-2-yl-phosphonates and 1,3-dithiol-2-yliden iminium salts with various substitutents on the dithiole cycles. Except for the un- or monosubstituted phosphonates, the one-pot procedure proves to be general and affords in all cases a significant improvement in the overall yields in TTF derivatives. The study has shown also that the formation of the intermediate adducts occurs in high yield, but their transformation into TTF derivatives, in presence of anhydrous acetic acid, is strongly sensitive to the nature of the various substituents, particularly on the iminium part.

The poor results in the syntheses of unsymmetrically substituted TTF derivatives carried out with mono or unsubstituted diethyl 1,3-dithiol-2-yl-phosphonates is here explained by the existence of an equilibrium between the cyclic and open forms of their corresponding carbanionic salt, with possible dimerisation of the open form. The monomeric cyclic form can react with a high reactive iminium salt, affording then the corresponding TTF derivative in moderate yield.

Preparation, crystal structures, EHT band calculations and physical properties of a semi-conducting κ-(EDS-EDT-TTF) 2 [Ag 2 (CN) 3 ] (1) and a new metallic-like species α-(BETS) 2 Ag(CN) 2 (2) are reported. κ-(EDS-EDT-TTF) 2 [Ag 2 (CN) 3 ] 1: M r =625.3, monoclinic space group P2 1 /c, a=15.157(9), b=8.732(2), c=13.51(2) A,β=90.94(3)°, V=1788 A 3 , Z=2, D c =2.324 g cm –3 , R=0.055 for 2572 reflections with F 2 ≥2σ(F 2 ). In this compound the organic molecules adopt the so-called κ type of packing. In the inorganic sublattice the [Ag 2 (CN) 3 ] – units form an infinite two-dimensional polymeric sheet. This compound shows a semi conducting behaviour, withσ 300 K =3.0×10 –4 S cm –1 and E a =120 meV. α-(BETS) 2 Ag(CN) 2 2: M r =1304.4, orthorhombic space group P2 1 2 1 2, a=9.5839(8), b=4.983(3), c=34.645(6), V=1654 A 3 , Z=2, D c =2.618 g cm –3 , R=0.057 for 1136 reflections with F 2 ≥2 σ(F 2 ). Its crystal structure consists of two-dimensional organic sheets separated by linear Ag(CN) 2 – anions. The organic molecules adopt the so-called α type of packing with a dihedral angle between two molecules belonging to two adjacent chains of ca. 78°. This compound shows metallic behaviour in the range 300-2 K, with σ 300 K =100 S cm –1 .

The synthesis is described of a series of conjugated donor-π-acceptor molecules where 1,3-diselenoles are the electron donor moieties and dicyanomethylene or N-cyanoimine groups function as the acceptor moieties. Alkenes and aryl groups act as the conjugated spacers. The UV-VIS absorption spectra of these molecules in solution possess a low energy band resulting from intramolecular charge transfer; the wavelength of this band varies significantly with the structure of the spacer group. The solution redox properties, studied by cyclic voltammetry, reveal a reversible one-electron oxidation wave, attributed to the formation of the radical cation of the 1,3-diselenol-2-ylidene moiety, and an irreversible one-electron reduction to form the radical anion located on the dicyanomethylene or N-cyanoimine groups. The X-ray crystal structure of 9 9-(1,1-dicyanomethylene)-10-(4,5-dimethyl-1,3-diselenol-2-ylidene)-9,10-dihydroanthracene 14 is reported. The molecule is strained and adopts a “butterfly conformation” in the ground state due to unfavourable peri-interactions between the 1,3-diselenole selenium atoms and the peri hydrogens.

Radical polymerizations of methyl methacrylate were carried out in the presence of photoiniferters (RDC) containing a piperidino-dithiocarbamate group. The effects of the structure of the RDC on the photopolymerization in the presence or absence of a transfer agent such as tetraethylthiuram disulfide (TD) were investigated. The influence of the presence of a transfer agent (TD) on the living character and the control of the polymerization were also discussed.

We present c-axis resistivity measurements performed on the organic conductors and under pressure. The aim is to probe the density of states of quasi-one dimensional compounds the high temperature properties of which are those of a Luttinger liquid. It is found that the 1-D Luttinger description breaks down below a specific pressure-dependent temperature, giving rise to a transient regime. The Fermi liquid behaviour is however restored at low temperature i.e. around 10 K, as evidenced by NMR measurements. Accordingly, two different energy scales 100 K and 10 K are required to get a fair understanding of all observed physical phenomena. Our interpretation supports the picture of a power law exponent for the correlation functions of the order of 0.25–0.30.