123 research outputs found
Pulizia in linea del filo metallico su impianti di trafilatura ad alta velocità: Innovazione, ecologia e performance
No full textNei processi di trafilatura il filo metallico subisce una sequenza di passaggi forzati attraverso matrici (filiere), di diametro decrescente,
che ne riducono progressivamente la sezione fino al valore desiderato. Per assicurare il passaggio attraverso le filiere, riducendo
quanto più possibile l’attrito, è necessaria una lubrificazione, ottenuta tramite l’utilizzo di diverse sostanze chimiche: si passa da
emulsioni acqua/olio per lubrificazione liquida, a stearati di sodio e/o calcio o polimeri per lubrificazione solida. Tali lubrificanti
devono formare un film sottile, omogeneo e ben adeso al filo, ma devono poter essere rimossi al termine dei processi di riduzione
di sezione se si desidera ottenere un filo superficialmente pulito e pronto per eventuali successivi trattamenti galvanici, termici o
di rivestimento superficiale di vario genere. In questo articolo verrà analizzata una tecnica innovativa per la pulizia del filo, in linea
con l’impianto di trafilatura, applicabile sia a monte del processo (pulizia/decapaggio della vergella) sia a valle (pulizia finale prebobinatura).
La tecnica in esame, basata su un processo elettrochimico, può essere integrata su linee già esistenti e va a sostituire le vasche
chimiche o ad ultrasuoni di pulizia post-trafilatura, facendo uso di elettroliti a minor impatto ambientale rispetto ai tradizionali
liquidi per sgrassaggio acido e alcalino
Metodo di preparazione del composto magnetocalorico AlFe2B2
No full textÈ descritto un metodo di preparazione del composto magnetocalorico AlFe2B2, del tipo che
prevede una reazione di combustione di una miscela di reagenti comprendenti polveri elementali di
ferro, alluminio e boro, o pre-alligate ferroalluminio, ferro-boro, detta combustione essendo
innescata per mezzo di una esposizione di detta miscela a microonde e detto composto
magnetocalorico AlFe2B2 essendo poi separato dai sottoprodotti di detta reazione di combustione,
caratterizzato dal fatto che dette microonde, sono utilizzate prevalentemente in campo elettrico (E
mode) o in campo magnetico (H mode), in modo tale che dette microonde, in campo prevalentemente
elettrico, tendano a surriscaldare le polveri di alluminio e boro, mentre dette microonde, in campo
prevalentemente magnetico, tendano a surriscaldare le polveri di ferro. È parte integrante della
presente invenzione anche una procedura di separazione del composto magnetocalorico AlFe2B2
dai sottoprodotti di detta reazione di combustione
Microwave-assisted preparation of multi principal element alloys by powder metallurgy approach
No full textAccording to literature, the synthetic route to produce High entropy alloys (HEAs) should guarantee short alloying time, efficient cooling and capability to operate in controlled atmosphere. Such conditions can be achieved using high frequency electromagnetic fields, like microwave heating. In this work FeCoNiCrAl and FeCoNiCuAl, both equiatomic and reinforced by the 10% wt. of SiC were prepared by microwave assisted techniques. Results show that direct microwave heating of the powder precursors occurs, until the ignition conditions are reached. The temperature and duration of the microwave-assisted process result much lower than other conventional powder metallurgy routes, but at the cost of a higher residual porosity. Sample characterization confirmed that the powder metallurgy approach is suitable to retain the shape of the load imparted during forming by uniaxial pressing. The homogeneity of the samples resulted in being good in all cases, without the dendritic segregation typically occurring by liquid phase processing. © 2017 European Powder Metallurgy Association (EPMA
A micro/nanoscale surface mechanical study on morpho-functional changes in multilineage-differentiated human mesenchymal stem cells.
No full textIn recent years MSCs have become a very attractive tool in tissue engineering and regenerative medicine because of their ability to be committed along several lineages through chemical or physical stimuli. Nevertheless their therapeutic potential and plasticity are not yet totally understood. This report describes the use of AFM together with conventional microscopies to obtain mechanical information on cell surfaces and deposited extra cellular matrix molecules, after inducing the differentiation of human MSCs towards three typical mesoderm phenotypes. The aim is to correlate morphological, functional, and mechanical aspects of human MSCs to obtain a deeper understanding of their great potential
EFFECTS OF REPEATED EXPOSURE TO HIGH-VOLTAGE ELECTRIC-DISCHARGES AND LOW-FREQUENCY ELECTROMAGNETIC-FIELDS ON CULTURED MOUSE P3X63AG8 PLASMACYTOMA CELLS
No full textMicrowave energy application to combustion synthesis: A comprehensive review of recent advancements and most promising perspectives
No full textMicrowave heating fundamentally differs from other heating techniques as the consequence of its unique characteristic of being based on the electromagnetic energy transfer from the microwaves source to the interacting material, which according to its electric, dielectric, and magnetic properties can convert the absorbed energy into heat. This peculiar heating mechanism is at the basis of plenty of unquestionable advantages that were reported during the last three decades in most of the different branches of chemistry as well as materials science, thus including also combustion synthesis. After a brief overview of the microwave heating fundamentals as well as of the different components constituting the scientific microwave applicators, all the most significant and recent advancements in the use of microwaves as energy source in both solid-state as well as solution combustion synthesis processes will be comprehensively reviewed, highlighting the unique opportunities arising from the coupling of these two energy efficient techniques. Moreover the possible employment of less conventional frequencies as well as the use of new-generation solid state generators will be critically discussed also in the framework of scaling-up and microwave reactor design considerations
A Micro-nanoscale surface mechanical study on morpho-functional changes in multilineage differentiateted human mesenchymal stem cells
No full textIn recent years MSCs have become a very attractive tool in tissue engineering and regenerative medicine because of their ability to be committed along several lineages through chemical or physical stimuli. Nevertheless their therapeutic potential and plasticity are not yet totally understood. This report describes the use of AFM together with conventional microscopies to obtain mechanical information on cell surfaces and deposited extra cellular matrix molecules, after inducing the differentiation of human MSCs towards three typical mesoderm phenotypes. The aim is to correlate morphological, functional, and mechanical aspects of human MSCs to obtain a deeper understanding of their great potential
Case Study of Physiotherapy Treatment of a Patient after Total Knee Replacement
No full textTitle of the Thesis: Case Study of Physiotherapy Treatment of a Patient after Total Knee Replacement. Author: Osama Ali Trombi Work Placement: Rehabilitační Nemocnice Beroun Summary I divided the bachelor's thesis, which I wrote myself, into two parts. The first is the general part, which describes the overall anatomy of the knee joint (bones, muscles, ligaments, nerves and blood supply), as well as surgical and non-surgical approaches to the treatment of the knee joint. Furthermore, information on the kinesiological and biomechanical properties of the knee joint. In the second part, the practical part, I analyzed the procedures I performed with the patient. All clinical examinations including their results, subsequent therapeutic sessions, final assessment and results of conclusions are also included in the practical part of the bachelor thesis. The final part contains a list of used literature, tables, abbreviations, patient consent and the consent of the ethics committee. Key Words: knee joint, physiotherapy treatment, Knee replacement, knee exercises, Osteoarthritis
Případová studie pacienta po totální náhradě kolene
No full textTitle of the Thesis: Case Study of Physiotherapy Treatment of a Patient after Total Knee Replacement. Author: Osama Ali Trombi Work Placement: Rehabilitační Nemocnice Beroun Summary I divided the bachelor's thesis, which I wrote myself, into two parts. The first is the general part, which describes the overall anatomy of the knee joint (bones, muscles, ligaments, nerves and blood supply), as well as surgical and non-surgical approaches to the treatment of the knee joint. Furthermore, information on the kinesiological and biomechanical properties of the knee joint. In the second part, the practical part, I analyzed the procedures I performed with the patient. All clinical examinations including their results, subsequent therapeutic sessions, final assessment and results of conclusions are also included in the practical part of the bachelor thesis. The final part contains a list of used literature, tables, abbreviations, patient consent and the consent of the ethics committee. Key Words: knee joint, physiotherapy treatment, Knee replacement, knee exercises, Osteoarthritis.Název: Případová studie pacienta po totální nahrade kolene Autor: Osama Ali Trombi Pracoviště: Rehabilitační Nemocnice Beroun Souhrn: Bakalářskou práci, kterou jsem napsal sám, jsem rozdělil na dvě části. První je obecná část, která popisuje celkovou anatomii kolenního kloubu (kosti, svaly, vazy, nervy a krevní zásobení), zároveň i chirurgické a nechirurgické přístupy k léčbě kolenního kloubu. Dále informace o kineziologických a biomechanických vlastnostech kolenního kloubu. V druhé části, praktické části, jsem analyzoval postupy, které jsem s pacientem provedl. Všechna klinická vyšetření zahrnující jejich výsledky, následující terapeutická sezení, závěrečné posouzení a výsledky závěrů jsou také obsaženy v praktické části bakalářské práce. Závěrečná část obsahuje seznam použité literatury, tabulky, zkratky, souhlas pacienta a souhlas etické komise. Klíčová slova: kolenní kloub, fyzioterapeutická léčba, náhrada kolena, cvičení kolena, osteoartrozaFyzioterapieFakulta tělesné výchovy a sportuFaculty of Physical Education and Spor
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