Search results for " Metalli"
showing 10 items of 50 documents
Lead in the Bones of Cows from a Medieval Pb-Ag Metallurgical Settlement: Bone Mineralization by Metalliferous Minerals
2021
Pb contents (13-53 mg kg−1) and pathological changes in almost complete cow skeletonsdiscovered in graves adjacent to Pb and Ag smelting furnaces active in the Silesian-Cracovian region, in the mid-12th century are reported in the article. In addition to Pb,elements such as Zn, Cd, Fe, Mn, Cd, and Ba characteristic of Zn-Pb-Ag ores in the regionwere identified. Bone fragments and the soil in which they had lain for almost 800 yearswere examined by SEM, EDS. XRD was used to identify minerals present in soils. Theenrichment of the bones with Zn, Pb, Fe, Mn, and Cd is associated with the remobilisationof elements from soil contaminated with primary and synthetic phase-rich metals. In bioticmat…
Stent-assisted detachable coil embolization of wide-necked renal artery aneurysms
2017
Renal artery aneurysms (RAAs) are rare with an estimated incidence of 0.1% in the general population, and they represent approximately 25% of all visceral aneurysms. The gold standard of treatment is open surgery, but it is associated with a high risk of nephrectomy, mortality, and morbidity. Less invasive endovascular therapies are becoming increasingly common for the treatment of RAAs. Here, we aimed to report three cases of wide-necked complex renal artery aneurysms treated endovascularly using stent-assisted coil embolization with self-expandable stent nitinol Solitaire AB and Concerto Axium coils. In addition, we describe the use of the waffle-cone technique in a case of wide-necked sa…
BioMet14 XIV PharmacoBioMetallics Pisa, 24-25 ottobre 2014
2014
Properties Augmentation of Cast Hypereutectic Al–Si Alloy Through Friction Stir Processing
2022
AbstractThe present endeavour is to augment mechanical attributes via friction stir processing (FSP) in hypereutectic aluminium–silicon castings by the means of microstructural modifications and defects reduction. Wherein, the study proceeds with mainly two approaches namely, alteration in tool revolution (TR) and the number of FSP passes. The prepared specimens were evaluated investigating volume fraction of porosities, microstructural characterizations and microhardness. Therefrom, the specimen with highest number of passes delivered most uniform properties resulting from the reduction in casting porosities and refined silicon particle uniform distribution throughout friction stir process…
Il Progetto ATENA: Applicazione di metodologie innovative per la conservazione di manufatti metallici e ceramici da scavo archeologico e per il recup…
2007
Qui di seguito viene illustrato il progetto scientifico ATENA, svolto presso l'Istituto per lo Studio dei Materiali Nanostrutturati (ISMN) del Consiglio Nazionale delle Ricerche (CNR) e co-finanziato dal MIUR con Decreto Direttoriale 9-10-2002, n. 1105/2002. Il progetto si propone di applicare avanzate tecniche diagnostiche strumentali al fine di acquisire la dettagliata conoscenza microchimica e microstrutturale di manufatti metallici e ceramici antichi, di definirne il meccanismo di alterazione e/o degrado e di progettare, sintetizzare e validare opportuni prodotti e formulazioni per il restauro conservativo di tali manufatti. Le conoscenze acquisite sono utilizzabili anche per il recuper…
Theory of heterogeneous viscoelasticity
2015
We review a new theory of viscoelasticity of a glass-forming viscous liquid near and below the glass transition. In our model we assume that each point in the material has a specific viscosity, which varies randomly in space according to a fluctuating activation free energy. We include a Maxwellian elastic term and assume that the corresponding shear modulus fluctuates as well with the same distribution as that of the activation barriers. The model is solved in coherent-potential approximation (CPA), for which a derivation is given. The theory predicts an Arrhenius-type temperature dependence of the viscosity in the vanishing-frequency limit, independent of the distribution of the activatio…
Efficacy of lumen-apposing metal stents or self-expandable metal stents for endoscopic ultrasound-guided choledochoduodenostomy: a systematic review …
2020
Abstract Background Endoscopic ultrasound (EUS)-guided biliary drainage is becoming an option for palliation of malignant biliary obstruction. Lumen-apposing metal stents (LAMS) are replacing self-expandable metal stents (SEMS). The aim of this meta-analysis was to evaluate the efficacy and safety of LAMS and SEMS for EUS-guided choledochoduodenostomy (EUS-CDS). Methods A meta-analysis was performed using PRISMA protocols. Electronic databases were searched for studies on EUS-CDS. The primary outcome was clinical success. Secondary outcomes were technical success, reintervention, and adverse events. We used the random effects model with the DerSimonian–Laird estimation, and the results were…
Study of the reactive dynamics of nanometric metallic multilayers using Molecular Dynamics: the Al−Ni system
2012
A molecular dynamics study of a layered Ni-Al-Ni system is developed using an embedded atom method potential. The specific geometry is designed to model a Ni-Al nanometric metallic multilayer. The system is initially thermalized at the fixed temperature of 600 K. We first observe the interdiffusion of Ni and Al at the interfaces, which is followed by the spontaneous phase formation of B2-NiAl in the Al layer. The solid-state reaction is associated with a rapid system's heating which further enhances the diffusion processes. NiAl phase is organized in small regions separated by grain boundaries. This study confirms the hypothesis of a layer-by-layer development of the new phase. For longer t…