3,411 research outputs found
Theoretical investigation of topological ferrimagnetic intertwining double chain
In this paper, a novel trimeric chain approach to organometallic ferrimagnetics is proposed. The inter and intratrimer exchange interaction has been determined to be antiferromagnetic from a theoretical model magnetic susceptibility. The Curie law observed at very low temperature (q = 5.764 K l0) contrasts with significant ferromagnetic behaviour. The magnetic data were fitted with the IDC model. The compounds interestingly exhibit ferrimagnetic interactions with gCu1 =1.81, gCu2 =2.04 and gCu3 =2.43; J1 =-89.93K and J2= -2.68 KIn this paper, a novel trimeric chain approach to organometallic ferrimagnetics is proposed. The inter and intratrimer exchange interaction has been determined to be antiferromagnetic from a theoretical model magnetic susceptibility. The Curie law observed at very low temperature (q = 5.764 K l0) contrasts with significant ferromagnetic behaviour. The magnetic data were fitted with the IDC model. The compounds interestingly exhibit ferrimagnetic interactions with gCu1 =1.81, gCu2 =2.04 and gCu3 =2.43; J1 =-89.93K and J2= -2.68
Maladie de kimura: À propos d’un cas
Introduction :  Mots-clés : Maladie de Kimura, parotide, chirurgie.La maladie de Kimura ou lymphogranulome éosinophile est une pathologie inflammatoire chronique très rare, d’étiologie inconnue. Nous rapportons un cas de maladie de Kimura à localisation parotidienne et à travers une revue de la littérature, rappelons les principales caractéristiques cliniques, paracliniques, thérapeutiques et évolutives de cette pathologie. Matériel et méthodes : Patient de 17 ans qui a consulté devant l’apparition d’une tuméfaction de la région parotidienne gauche évoluant depuis un an et sans paralysie faciale. Résultats : L’échographie cervico-parotidienne a révélé une parotide gauche hypertrophiée siège de multiples nodules hypoéchogènes. La tomodensitométrie cervico-faciale a mis en évidence une glande parotide gauche augmentée de taille et de structure hétérogène nodulaire sans adénopathies cervicales. La cytopontion était non concluante. Le patient a bénéficié d’une parotidectomie exofaciale gauche et l’étude anatomopathologique de la pièce opératoire revenue en faveur de la maladie de Kimura. Les suites opératoires étaient simples. Le recul est d’un an sans récidive. Discussion : La Maladie de Kimura se caractérise cliniquement par des nodules sous cutanés de localisation cervicofaciale, une augmentation du volume des glandes salivaires et des adénopathies satellites. Son diagnostic est histologique reposant sur l’identification d’une hyperplasie follicullaire avec des abcès à polynucléaires éosinophiles. Le traitement est chirurgical le plus souvent mais dans certains cas la corticothérapie est proposée. Ce diagnostic doit cependant rester à l’esprit devant toute masse cervico-faciale
The Detection of Ionizing Radiation by Plasma Panel Sensors: Cosmic Muons, Ion Beams and Cancer Therapy
The plasma panel sensor is an ionizing photon and particle radiation detector
derived from PDP technology with high gain and nanosecond response.
Experimental results in detecting cosmic ray muons and beta particles from
radioactive sources are described along with applications including high energy
and nuclear physics, homeland security and cancer therapeuticsComment: Presented at SID Symposium, June 201
Effects of Phenol Addition on Oil Extraction from Moroccan Oil Shale by Supercritical Toluene
In the present work, the effect of phenol on the supercritical extraction of the organic matter from Tarfaya's oil shale with toluene was evaluated. The experimental results showed clearly that phenol had a significant effect on the yield and the composition of the oils obtained. Moreover, it was shown that phenol was a very efficient modifier for oil shale, giving a good yield of recovery and a suitable maturation of the organic matter. The pitches prepared by mixing phenol and toluene contain more aromatics and have a high char yield at 950 °C compared to those obtained by extraction with supercritical toluene alone
The Certification of ATLAS Thin Gap Chambers Produced in Israel and China
Thin gap chambers (TGCs) are used for the muon trigger system in the forward
region of the LHC experiment ATLAS. A TGC consists of a plane of closely spaced
wires maintained at positive high voltage, sandwiched between resistive
grounded cathode planes with an anode wire to cathode plane gap distance
smaller than the wire-to-wire spacing. The TGCs are expected to provide a
trigger signal within 25 ns of the bunch spacing of the LHC accelerator, with
an efficiency exceeding 95%, while exposed to an effective photon and neutron
background ranging from 30 to 500 Hz/cm2. About 2,500 out of the 3,600 ATLAS
TGCs are being produced at the Weizmann institute in Israel, and in Shandong
University in China. Once installed in the ATLAS detector the TGCs will be
inaccessible. A vigorous production quality control program is therefore
implemented at the production sites. Furthermore, after chamber completion, a
thorough program of quality assurance is implemented to ensure the efficient
performance of the chambers during more than ten years of operation in the LHC
high rate environment. This program consists of a detailed mapping of the
detectors response using cosmic rays, as well as checking the chambers behavior
using a high rate radiation source. An aging test performed on five chambers in
a serial gas connection is presented. Finally the results of the chambers
certification tests performed at CERN before the installation in ATLAS are
described.Comment: Presented at 2004 IEEE Nuclear Science Symposium 2004, Rome, Oct 200
Measurement of shower development and its Moli\`ere radius with a four-plane LumiCal test set-up
A prototype of a luminometer, designed for a future e+e- collider detector,
and consisting at present of a four-plane module, was tested in the CERN PS
accelerator T9 beam. The objective of this beam test was to demonstrate a
multi-plane tungsten/silicon operation, to study the development of the
electromagnetic shower and to compare it with MC simulations. The Moli\`ere
radius has been determined to be 24.0 +/- 0.6 (stat.) +/- 1.5 (syst.) mm using
a parametrization of the shower shape. Very good agreement was found between
data and a detailed Geant4 simulation.Comment: Paper published in Eur. Phys. J., includes 25 figures and 3 Table
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