Search results for "taz"

Electron paramagnetic resonance line shape investigation of the Si-29 hyperfine doublet of the E'γ center in a-SiO2

2007

We report an experimental study by electron paramagnetic resonance (EPR) spectroscopy of the E′γ center and of its hyperfine structure, consisting in a pair of lines split by 42 mT. Our results show that two types of E′γ centers can be distinguished on the basis of the EPR line shapes of their main resonance line and hyperfine structure. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Electron paramagnetic resonance investigation on the hyperfine structure of the center in amorphous silicon dioxide

2007

Abstract We report an experimental investigation by electron paramagnetic resonance (EPR) spectroscopy on the hyperfine structure of the E δ ′ center in γ-ray irradiated amorphous silicon dioxide materials. This study has driven us to the determination of the intensity ratio between the hyperfine doublet and the main resonance line of this point defect. This ratio was obtained for a variety of silica samples and compared with the analogous ratio obtained for the E γ ′ defect. The comparison definitively confirms that the electronic wave function involved in the E δ ′ center is actually delocalized over four nearly equivalent Si atoms.

L'elemento soggettivo e la didattica della progettazione architettonica

2008

Ogni anno, con una certa quantità di ripetizioni e di innovazioni, si procede alla stesura di un programma didattico che, articolato in più voci (collocazione nel progetto formativo, obiettivi, contenuti, modalità d’esame, bibliografia essenziale), struttura le tappe di un percorso nei mesi in cui si sviluppa l’insegnamento. Nella presente riflessione, senza svalutare in alcun modo le conoscenze oggettive che possono concretizzarsi in una interpretazione dei punti della teoria della progettazione di Rossi, si vuole individuare un percorso didattico che parta dalla componente autobiografica dello studente. Per affrontare tale questione si dovrebbe spostare l’attenzione sul modo in cui gli…

Percepire, desiderare, rappresentare

2013

EGTA treatment causes the synthesis of heat shock proteins in sea urchin embryos.

2000

Paracentrotus lividus embryos, at post-blastular stage, when subjected to a rise in temperature from physiologic (20 degrees C) to 31 degrees C, synthesize a large group of heat shock proteins (hsps), and show a severe inhibition of bulk protein synthesis. We show, by mono- and two-dimensional electrophoresis, that also EGTA (ethylene glycol-bis[beta-aminoethyl ether] tetraacetic acid) treatment induces in sea urchin embryos both marked inhibition of bulk protein synthesis and the synthesis of the entire set of hsps. Furthermore, EGTA-treated sea urchin embryos are able to survive at a temperature otherwise lethal (35 degrees C) becoming thermotolerant. Because incubation with a different c…

Emozioni in movimento

2013

Protease inhibitor atazanavir induces leukocyte-endothelial cell interactions in the microvasculature

2008

Conformable eddy current array delivery

2016

The external surface of stainless steel containers used for the interim storage of nuclear material may be subject to Atmospherically Induced Stress Corrosion Cracking (AISCC). The inspection of such containers poses a significant challenge due to the large quantities involved; therefore, automating the inspection process is of considerable interest. This paper reports upon a proof-of-concept project concerning the automated NDT of a set of test containers containing artificially generated AISCCs. An Eddy current array probe with a conformable padded surface from Eddyfi was used as the NDT sensor and end effector on a KUKA KR5 arc HW robot. A kinematically valid cylindrical raster scan path…

KNOWN RESIDUAL STRESS SPECIMENS USING OPPOSED INDENTATION

2009

In order to test new theories for residual stress measurement or to test the effects of residual stress on fatigue, fracture, and stress corrosion cracking, a known stress test specimen was designed and then fabricated, modeled, and experimentally validated. To provide a unique biaxial stress state, a 60 mm diameter 10 mm thick disk of 316L stainless steel was plastically compressed through the thickness with an opposing 15 mm diameter hard steel indenters in the center of the disk. For validation, the stresses in the specimen were first mapped using time-of-flight neutron diffraction and Rietveld full pattern analysis. Next, the hoop stresses were mapped on a cross section of two disks usi…

Robotic path planning for non-destructive testing of complex shaped surfaces

2015

The requirement to increase inspection speeds for non-destructive testing (NDT) of composite aerospace parts is common to many manufacturers. The prevalence of complex curved surfaces in the industry provides significant motivation for the use of 6 axis robots for deployment of NDT probes in these inspections. A new system for robot deployed ultrasonic inspection of composite aerospace components is presented. The key novelty of the approach is through the accommodation of flexible robotic trajectory planning, coordinated with the NDT data acquisition. Using a flexible approach in MATLAB, the authors have developed a high level custom toolbox that utilizes external control of an industrial …