83 research outputs found
The inelastic Takahashi hard-rod gas
We study a one-dimensional fluid of hard-rods interacting each other via
binary inelastic collisions and a short ranged square-well potential. Upon
tuning the depth and the sign of the well, we investigate the interplay between
dissipation and cohesive or repulsive forces. Molecular dynamics simulations of
the cooling regime indicate that the presence of this simple interparticle
interaction is sufficient to significantly modify the energy dissipation rates
expected by the Haff's law for the free cooling. The simplicity of the model
makes it amenable to an analytical approach based on the Boltzmann-Enskog
transport equation which allows deriving the behaviour of the granular
temperature. Furthermore, in the elastic limit, the model can be solved exactly
to provide a full thermodynamic description. A meaningful theoretical
approximation explaining the properties of the inelastic system in interaction
with a thermal bath can be directly extrapolated from the properties of the
corresponding elastic system, upon a proper re-definition of the relevant
observables. Simulation results both in the cooling and driven regime can be
fairly interpreted according to our theoretical approach and compare rather
well to our predictions.Comment: 14 pages RevTex, 9 eps figure
Preparation and properties of adhesives based on phenolic resin containing lignin micro and nanoparticles: A comparative study
This work investigated, for the first time, the role of nanosized lignin (LNP), in comparison with microlignin (LMP), when introduced at two different weight amounts (5% and 10 wt%) in bulk phenol–formaldehyde resol as adhesive. Morphological analysis was performed to check out the dispersion and interfacial bonding of lignin in the phenolic resin. The curing process has been examined by differential scanning calorimetry (DSC), while the thermal stability of the composites has been evaluated by using thermogravimetric (TGA) and thermo-mechanical (TMA) analysis. Results exhibited that small amount of lignin could both favor the thermal cure reaction, due to its abundance of phenylpropane units, and the initial thermal resistance could be consequently improved, especially when the nano-sized lignin was used. Meanwhile, the effect of micro- and nano-modification on tensile shear strength of wood lap joints based on lignin-phenol–formaldehyde resol adhesives was also analyzed. Results showed that 5 wt% of LNP could positively increase the shear strength from 8.7 to 10.9 MPa, opening the possibility of using environmental friendly nanoscale lignin in cross linked traditional phenol wood adhesives with enhanced adhesion performance, strongly related to nanoparticles higher specific surface area and reactivity. Keywords: A. Resol resin, A. Lignin micro/nanoparticles, B. Thermal properties, D. Shear tes
Erratum to nodal management and upstaging of disease. Initial results from the Italian VATS Lobectomy Registry
[This corrects the article DOI: 10.21037/jtd.2017.06.12.]
Evaluation of the Thermal Diffusivity of Carbon/Phenolic Composites (CPCs) through Oxy-Acetylene Torch (OAT) Test—Part 1: Experimental Characterization and Preliminary Validation
Carbon/Phenolic Composites (CPCs) are essential to manufacture many portions of the nozzle assembly of Solid Rocket Motors (SRMs) which are essential both to preserve the independent access to space as well as for the homeland security. In our research, a feasible approach aimed at preliminary retrieving the in-plane and out-plane thermal diffusivity of CPCs through the Oxy-Acetylene Torch (OAT) tests was validated. The proposed approach showed to be effective and able to bypass some limitations of common protocols, especially in terms of capability to determine the thermal diffusivity of CPCs at high heating rates. A comprehensive work of comparison of the obtained data with state-of-the-art CPCs such as MX-4926 and FM-5014 has also been carried out, evidencing the effectiveness of the proposed method
OT equator biologic abutment. Un nuovo concetto di protesi fissa e rimovibile su impianti
In questo testo si propongono una serie di linee guida per ridurre il numero di sedute operative ed i costi nei casi complessi. La terapia \ue8 supportata scientificamente, ma anche arricchita dall\u2019arte di curare, partendo dalla prima visita del paziente edentulo e passando per le procedure operative dell\u2019implantoprotesi. L\u2019obiettivo \ue8 il completo recupero delle funzioni orali facendo dimenticare al paziente la mutilazione dell\u2019edentulismo.Il nostro obiettivo non \ue8 la trattazione sistematico-enciclopedica delle problematiche dell\u2019implantologia, ma gallerie di casi clinici che presentino alcune idee innovative con la formula del testo atlante.Alcuni dei casi presentati in questo eBook sono stati realizzati da dentisti generici fra cui alcuni nostri ex studenti, dimostrando come la procedura sia agevole ed alla portata di tutti.L\u2019auspicio degli Autori \ue8 che un sempre maggior numero di pazienti, grazie alla applicazione della implantoprotesi, recuperi un nuovo stato di benessere fisico, psichico e sociale ritrovando la gioia di vivere
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