Search results for " Phases"
showing 10 items of 74 documents
New trends in nonequilibrium statistical mechanics: classical and quantum systems
2020
The main aim of this special issue is to report recent advances and new trends in nonequilibrium statistical mechanics of classical and quantum systems, from both theoretical and experimental points of view, within an interdisciplinary context. In particular, the nonlinear relaxation processes in the dynamics of out-of-equilibrium systems and the role of the metastability and environmental noise will be overviewed. Three main areas of nonequilibrium statistical mechanics will be covered: slow relaxation phenomena and dissipative dynamics; long-range interactions and classical systems; quantum systems. New trends such as quantum thermodynamics and novel types of quantum phase transitions occ…
On critical properties of the Berry curvature in the Kitaev honeycomb model
2019
We analyse the Kitaev honeycomb model, by means of the Berry curvature with respect to Hamiltonian parameters. We concentrate on the ground-state vortex-free sector, which allows us to exploit an appropriate Fermionisation technique. The parameter space includes a time-reversal breaking term which provides an analytical headway to study the curvature in phases in which it would otherwise vanish. The curvature is then analysed in the limit in which the time-reversal-symmetry-breaking perturbation vanishes. This provides remarkable information about the topological phase transitions of the model. The Berry curvature in itself exhibits no singularities at criticality, nevertheless it distingui…
Consideration of the formation of solids and gases in steady state modelling of crevice corrosion propagation
2007
Abstract One of the challenges in the simulation of crevice corrosion propagation is the rigorous treatment of non-aqueous species (gas or solids), since the appearance of a new phase in a crevice will automatically have an impact on its geometry. This paper presents a simple approach, where heterogeneous reactions are considered in a post-processing step, by determining the conditions of potential, external chemistry (pH, chloride, …) or geometry under which gas or solid phases could appear in the crevice. Thus, as function of these conditions, stability diagrams for the different phases that are liable to appear in an actively propagating crevice can be constructed. Such diagrams (e.g. di…
On the use of ionic liquids as mobile phase additives in high-performance liquid chromatography. A review.
2015
The popularity of ionic liquids (ILs) has grown during the last decades in several analytical separation techniques. Consequently, the number of reports devoted to the applications of ILs is still increasing. This review is focused on the use of ILs (mainly imidazolium-based associated to chloride and tetrafluoroborate) as mobile phase additives in high-performance liquid chromatography (HPLC). In this approach, ILs just function as salts, but keep several kinds of intermolecular interactions, which are useful for chromatographic separations. Both cation and anion can be adsorbed on the stationary phase, creating a bilayer. This gives rise to hydrophobic, electrostatic and other specific in…
Enantioseparations with polysaccharide-based chiral stationary phases in HPLC. Application to the enantioselective evaluation of the biodegradability…
2023
The chiral nature of living systems has obvious implications for the biologically active compounds that interact with them. At the molecular level, chirality represents an intrinsic property of the essential building blocks of life, such as amino acids and sugars, and therefore, of peptides, proteins, enzymes, carbohydrates, nucleosides and a number of alkaloids and hormones. As a consequence, processes mediated by biological systems are stereochemistry-sensitive, and a pair of enantiomers can have different effects on living organisms. The scientific community has been studying the implications of chirality for life for more than a century. Today, it is still a topic of active research and…
Characterization of ATPase from maize shoot plasma membrane prepared by partition in an aqueous polymer two phase system
1986
41 ref.; International audience
Solid Phases as Protective Environments for Biomimetic Catalysts
2014
THE PERFORATED BUILDING’S ENVELOPE: GUIDING THE EARLY DESIGN PHASES
In passato gli involucri edilizi perforati sono stati talvolta ricondotti ad alcuni elementi architettonici tradizionali (come, ad esempio, la ‘Mashrabiyya’), in cui gli elementi forati acquisiscono quasi significati archetipici, nell’assumere ruoli tecnologici e ambientali che rispecchiano i valori della comunità, le condizioni socio-economiche e le esigenze ambientali degli occupanti. Oggi, invece, l’involucro edilizio perforato costituisce una tendenza architettonica che ha iniziato a manifestarsi a livello globale all’inizio del nuovo millennio, alla quale ha contribuito l’emergere della tecnologia digitale con i suoi effetti sull’innovazione di tecniche, materiali, realizzazioni, prest…
Reliability of measurements during countermovement jump assessments: Analysis of performance across subphases
2020
The aim of this study was to examine the reliability of performance measures in the different phases and sub-phases of the countermovement jump (CMJ). Seventeen male athletes competing at a regional level completed 204 valid trails consisting of the execution of maximal hands-on-waist CMJs performed on a force platform. The vertical ground reaction force (VGRF) data obtained at a sampling frequency of 1000 Hz were used to calculate performance-derived variables and determine key points and jump sub-phases. The relative reliability of 92 variables was assessed using the intraclass correlation coefficient (ICC) from a two-way mixed effects model analyzing the time, force, power, velocity, and…
Personalizzazione e orientamento per una didattica inclusiva. Il processo di ricerca, le azioni di ricerca.
2017
Sono presentati gli obiettivi, le ipotesi e le modalità di verifica delle nove azioni in cui si è articolato il progetto di rilevante interesse nazionale realizzato dall’unità di ricerca dell’Università di Palermo tra il 2013 e il 2016. Il contributo evidenzia in che modo le nove azioni di ricerca hanno contribuito a realizzare una didattica inclusiva partendo dal presupposto della personalizzazione dell’insegnamento. L’autore, in qualità di coordinatore dell’unità locale di ricerca, mostra il filo rosso che unisce tra loro le diverse azioni di ricerca che si sono svolte parallelamente in Sicilia e le collega con le finalità dell’intero progetto nazionale. The objectives, hypotheses and pro…