Search results for "Pere"

Plant colonization of a bare peat surface: population changes and spatial patterns

1992

. Changes in size and spatial arrangement of plant populations established on an initially bare peat surface were described over a period of 5 yr by following plant individuals on a 1-cm grid in an area of 10 m x 25 m. The spatial pattern of populations and association between species was analyzed statistically. The study site was very slowly colonized by 14 perennial plant species. The early successional stage was dominated by Carex rostrata, with a clumped spatial distribution, and the homogeneously distributed Eriophorum vaginatum and Pinus sylvestris. Both the growth in size of populations and changes in their spatial distribution were interpreted as a result of species dispersal abilit…

Prípiat o el Sol: en diálogo con la propuesta ecosicialista de Joaquim Sempere

2019

G. Herglotz’ Behandlung von Beschleunigungswellen in seiner Vorlesung «Mechanik der Kontinua» angewandt auf die Stosswellen von Christoffel

1981

Following a lecture delivered by Herglotz in 1925/26 we briefly treat acceleration waves in hyperelastic materials. Our main result is a divergence equation for the squared Euclidean norm of the so-called ‘wave vector’. We then apply Herglotz’ method (devised for acceleration waves) to the propagation of such first order discontinuities in elastic bodies as were treated by Christoffel in [1].

Unveiling the Intramolecular Ionic Diels–Alder Reactions within Molecular Electron Density Theory

2021

The intramolecular ionic Diels–Alder (IIDA) reactions of two dieniminiums were studied within the Molecular Electron Density Theory (MEDT) at the ωB97XD/6-311G(d,p) computational level. Topological analysis of the electron localization function (ELF) of dieniminiums showed that their electronic structures can been seen as the sum of those of butadiene and ethaniminium. The superelectrophilic character of dieniminiums accounts for the high intramolecular global electron density transfer taking place from the diene framework to the iminium one at the transition state structures (TSs) of these IIDA reactions, which are classified as the forward electro density flux. The activation enthalpy ass…

Orbital Rotations induced by Charges of Polarons and Defects in Doped Vanadates

2020

We explore the competiton of doped holes and defects that leads to the loss of orbital order in vanadate perovskites. In compounds such as La$_{1-{\sf x}}$Ca$_{\,\sf x}$VO$_3$ spin and orbital order result from super-exchange interactions described by an extended three-orbital degenerate Hubbard-Hund model for the vanadium $t_{2g}$ electrons. Long-range Coulomb potentials of charged Ca$^{2+}$ defects and $e$-$e$ interactions control the emergence of defect states inside the Mott gap. The quadrupolar components of the Coulomb fields of doped holes induce anisotropic orbital rotations of degenerate orbitals. These rotations modify the spin-orbital polaron clouds and compete with orbital rotat…

Architettura e funzionalità dei manufatti stradali: Analisi di un caso studio.

2008

Sistematica del Falco pellegrino (Falco peregrinus) in Italia

2021

Validated data and published studies indicate that four subspecies are present in continental Italy and its surrounding islands. Two of these subspecies (F. p. peregrinus and F. p. brookei) represent breeding populations, while the other two (F. p. calidus and F. p. pelegrinoides) winter and migrate in the country. Indeed, the European subspecies (F. p. peregrinus) has the most intriguing status, as it can both breed and winter. The exact range of the breeding population is not well-defined - it probably occurs in alpine and pre-alpine areas, perhaps reaching the Apennines of central Italy. Individuals originating from northern European countries in autumn and winter certainly implement thi…

IL FALCO PELLEGRINO (Falco peregrinus) IN SICILIA

2021

having doubled in number during the period 1978-2006, the population of the Peregrine Falcon Falco peregrinus living in Sicily currently seems to be stable, and has very probably reached the carrying capacity at the current ecological conditions of the insular ecosystems. A continuous standardized census (2010-2019) estimated at least 257 pairs scattered across the main island, plus some 13-15 pairs living on the small islands around Sicily. The population is not randomly distributed, but rather it is concentrated in all the suitable habitats of the island, nesting in either small crags or large cliffs from sea level to 1,424 m asl; it is rarer in the north-eastern corner (Peloritani, Nebro…

Falcó pelegrí, Halcón peregrino (VER0000164)

Altres noms vulgars: Peregrine Falcon (Anglès), Faucon pèlerin (Francès), Wanderfalke-peregrinus (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 5-2 Hembra Adulto

Falcó pelegrí, Halcón peregrino (VER0000165)

Altres noms vulgars: Peregrine Falcon (Anglès), Faucon pèlerin (Francès), Wanderfalke-peregrinus (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 5-2 Macho Adulto