Search

Recoil spectrometry using heavy ions proposed in 1976 by L’Ecuyer has evolved into a universal IBA technique. Few years later an experimental setup for simultaneous light and medium heavy element detection including a compact ΔE(gas)–E r (solid) telescope, was developed at the Tandem accelerator of IFIN-HH. To increase the resolution, an integrated preamplifier was mounted close to the ionization chamber. The calibration procedure for the telescope and the software for the quantitative evaluation of the data are briefly presented. Recently, a 3 MV Tandetron accelerator has been installed and commissioned at the IFIN-HH. Among several ion-beam techniques for detection and depth profiling of hydrogen isotopes, Elastic Recoil Detection Analysis (ERDA) technique using a low energy 4 He beam, proposed by Doyle and Peercy, is particularly advantageous. By measuring simultaneously both the H or D recoiling at a forward angle and backscattered 4 He ions, a rather complete characterization of the sample can be achieved. Selected results from our investigations, obtained using these facilities, are presented.

When dealing with cultural heritage artifacts, the use of non-invasive and non-destructive analyses techniques is a must . Determination of the surface corrosion layers and coin composition is important both for identifying compounds that form different alloys (which can be considered support material for important objects, such as numismatic artifacts), and also for their conservation. The selection of analytical techniques is of great importance, as it is a strict condition that the structure of the artifacts should not be affected. The paper presents the archaeometallurgical study of seven silver coins, using several nuclear techniques (X-ray fluorescence – XRF, X-ray diffraction – XRD, Particle induced X-ray emission – PIXE) and optical microscopy. The study was performed using bulk methods and micro-area measurements in order to establish their composition, as well as the presence of corrosion products. This could, in turn, provide information in support of the categorization in genuine/possible forgery. From the analyzed set of samples, six can be surely categorized as genuine, while one raises some questions. A decisive conclusion cannot be drawn for one of the analyzed samples, but the scientific evidences suggest either a misstruck or a forgery approximately contemporary with the original issue of these coins.

In this work we present the deposition of amorphous SiC thin films by radiofrequency dual magnetron sputtering. The dependence of the deposited films properties over the discharges electrical power and the effect of hydrogenous species (H 2 and/or D 2 ) addition to main discharge gas (Ar) were investigated. Accurate elemental analysis of the samples, including detection of hydrogen and deuterium, was performed by ion beam analysis (IBA) techniques: RBS (Rutherford Backscattering Spectrometry) and ERDA (Elastic Recoil Detection Analysis). SiC x thin films with thicknesses between 1700 and 4500 A and C/Si ratio between 0.2/1 and 1.25/1 were obtained in different deposition conditions. The results prove that thin films of amorphous SiC with well controlled properties can be produced using radiofrequency dual magnetron sputtering.

We present the QENS measurements result obtained at LLB using the MIBEMOL-TOF neutron spectrometer devoted to the study of sodium alginate–heavy water molecular dynamics behaviour, in an observation time range of 15 ns–1 ps. The data analysis allowed us to reveal the molecular motion manner of the two components of the system, as well as the dynamical parameters associated with various types of diffusion performed by water molecules constrained to move in the confined spaces created by the biopolymer chains. The various molecular groups belonging to these chains perform, at their turn, rotational diffusion motions in restricted spaces that can be described in terms of jump diffusion in a spherical potential model. From the elastic intensity we have calculated the elastic incoherent structure factor, EISF which reveals a molecular diffusion motion in spherical potential. At the same time we have obtained the mean square displacement (MSD), which is an increasing function of temperature presenting two slope changes at 145 and 185 K, respectively. These transition temperatures were associated with the molecular rotations release and translation outset, respectively.

The paper presents the last of our QENS and INS measurements on triglycine sulphate DTGS (ND3) at NEAT – BENSC neutron spectrometer. Using an energy window of 0.093 meV we have completed the information obtained in our previous measurements that were carried on non-deuterated TGS. By replacing the protons from amino groups of TGS with deuterons we have been able to observe the dynamical changes in the QENS pattern. The quasielastic line broadening in this case is mainly due to the flip jump diffusion motion of the protons which belong to CH2 group of the GI glycine molecule in DTGS. The residence time associated to this motion is about 4.2 ps. The second part of the paper is devoted to lattice phonons and internal molecular normal modes. The peaks observed in the generalized density of states were compared with optical spectroscopy data. The agreement is good.

Molecular dynamics of the ammonium dihydrogen phosphate, ADP, was studied by neutron scattering spectroscopy using an energy window of 100 μeV. This compound exhibits an order–disorder phase transition at T c = 148 K from antiferroelectic phase to paraelectric phase. The entire ADP lattice dynamics is dominated by a network of different N–H⋯O and O–H⋯O hydrogen bonds that are broken above critical temperature T c . In the ordered phase the molecular electric dipoles appear as a result of hydrogen ordering lateral configuration around PO 4 groups. The dynamics of ammonium group NH 4 plays also an important role in the phase transition. The quasielastic lines give information about ammonium reorientational diffusion above T c while the inelastic part of the spectrum provides useful information about ordered proton modes coupled with acoustic ADP lattice modes. At the same time the low energy transfer domain between 2 meV and 8 meV is very sensitive to phase transition. In the disordered phase the number of states increases compared with ordered phase, in a way similar with the solid–glass phase transition.

Introduction L’hypothermie peroperatoire (HPT°) est un facteur d’inconfort au reveil et de morbidite perioperatoire. C’est aussi un indicateur qualitatif. L’objectif de cette etude etait d’evaluer la frequence et les facteurs de risque de survenue d’une hypothermie au decours de la cesarienne. Materiel et methodes Etude observationnelle retrospective, monocentrique. Notre base de donnees anonyme renseignee prospectivement nous a permis d’extraire les informations concernant toutes les cesariennes realisees dans notre etablissement de 2010 a 2013 inclus. Ont ete releves pour chaque annee, le nombre de cesariennes realisees ; la presence ou non d’une HPT° definie par une T° centrale ≤ 35,5 °c (mesure tympanique) a l’arrivee en SSPI ; la valeur de la temperature en cas d’hypothermie. Les facteurs de risque potentiels suivant ont ete analyses en analyse univariee : l’âge ; la classe ASA ; Urgence/Programmee ; type d’anesthesie (Peridurale, APD/Rachianesthesie, Rachi/Anesthesie Generale, AG) ; duree d’intervention ; l’horaire : jour (08h30–18 h)/Garde (18h–22h30)/Nuit Profonde (NP) (22h30–08h30). Resultats Les donnees concernant les 2620 cesariennes sont precisees dans le Tableau 1 . Discussion Ces resultats suggerent une rupture de la « chaine du chaud » dans la prise en charge de la parturiente pour cesarienne en nuit profonde. Une analyse prospective qualitative est en cours afin d’identifier les causes.

Introduction La fracture de l’extremite superieure du femur (FExSuP) est un des motifs les plus frequents d’admission en traumatologie. Le retard au traitement chirurgical augmente la morbi-mortalite. L’objectif de cette etude est de decrire et comparer les delais et les facteurs de retard au traitement chirurgical dans deux etablissements publics de sante presentant des caracteristiques et conditions d’accueil differentes. Materiel et methodes Etude observationnelle retrospective, bicentrique. Nous avons analyse les dossiers des patients admis pour FexSuP sur la periode 2012 et 2013 dans un centre hospitalo-universitaire (CHU) et non universitaire (CHG) tres proches geographiquement de Seine Saint-Denis. Ont ete exclues les fractures pathologiques et sur materiel prothetique. Le CHU est un des 3 centres du departement participant a la Permanence des Soins en Etablissements de Sante (PDSES) accueillant les urgences toutes disciplines confondues. Il dispose d’une salle d’urgence H24. Le CHG, accueil les urgences hors nuit profonde (8h30–22h30), il ne participe pas a la PDSES. Une revue des dossiers a la recherche des facteurs de retard d’acces a la chirurgie a ete realisee lorsque celle-ci etait > 3 jours. Apres analyse initiale de 5 dossiers par centre par un binome anesthesio-chirurgical, 2 facteurs de retard ont ete identifies: Organisationel: disponibilite/priorisation du bloc operatoire (ORG) et Medical (MED). Les causes MED comprenaient: demande d’avis ou d’examen(s) complementaire(s) inutile(s) (MED-I); (3): medical justifie (MED-J); (4) Gestion des anti-agregants plaquettaires (AAP); (5) Gestion des anticoagulants (ATC). Resultats Six cent soixante-dix-neuf patients ont ete admis pour FexSuP sur la periode 2012–2013 (394 au CHU). La repartition (en %) des patients selon les delais d’acces a la chirurgie dans les deux hopitaux sont exprimes dans la figure. Un retard d’acces a la chirurgie etait encore observe apres 3 jours chez 128 (32 %) et 48 (17 %) des patients dans le CHU et le CHG respectivement, p Fig. 1 ). Discussion L’acces au traitement chirurgical des FexSuP est retarde dans le CHU compare au CHG notamment en raison de contraintes organisationnelles liees a la PDSES. Une reflexion doit etre menee pour apporter des mesures correctrices comme par exemple une meilleure disponibilite du bloc operatoire pour les urgences. Les protocoles medicaux concernant notamment la gestion des AAP et des ATC doivent aussi etre discutes et harmonises afin de limiter les retards inutiles de prise en charge.