2,760 research outputs found
Preface : Why Do Emotions History?
L'ampliació del camp de la història de les emocions per tenir una major participació dels acadèmics espanyols i una major atenció a la seva aplicació a la història espanyola -que aquest volum reflecteix i promou- és un fet que mereix ser celebrat. Un dels diversos senyals de l'èxit d'aquest vibrant sotscamp és l'ampliació del seu abast geogràfic, i Espanya apareix aquí com un exemple clau. Agraeixo la invitació per realitzar algunes aportacions sobre aquest camp a tall d'introducció.La ampliación del campo de la historia de las emociones para tener una mayor participación de los académicos españoles y una mayor atención a su aplicación a la historia española - que este volumen refleja y promueve - es un hecho que merece ser celebrado. Una de las diversas señales del éxito de este vibrante subcampo es la ampliación de su alcance geográfico, y España aparece ahí como un ejemplo clave. Agradezco la invitación para realizar algunas aportaciones sobre este campo a modo de introducción.Expansion of the field of emotions history to include greater participation by Spanish scholars and greater attention to applications of the approach to Spanish history - which this volume reflects and promotes - is a truly welcome development. It's clear that one of the several signs of success in this vibrant subfield is extending the geographical range, and Spain is emerging as a key case in point. I welcome the invitation to contribute a few comments about the field by way of introduction
Burner rig corrosion of SiC at 1000 deg C
Sintered alpha-SiC was examined in both oxidation and hot corrosion with a burner rig at 400 kPa (4 atm) and 1000 C with a flow velocity of 310 ft/sec. Oxidation tests for times to 46 hr produced virtually no attack, whereas tests with 4 ppm Na produced extensive corrosion in 13-1/2 hr. Thick glassy layers composed primarily of sodium silicate formed in the salt corrosion tests. This corrosion attack caused severe pitting of the silicon carbide substrate which led to a 32 percent strength decrease below the as-received material. Parallel furnace tests of Na2SO4/air induced attacked yielded basically similar results with some slight product composition differences. The differences are explained in terms of the continuous sulfate deposition which occurs in a burner rig
Geology and ground-water resources of the island of Oahu, Hawaii
Prepared in cooperation with the U.S. Geological survey.Bibliographical footnotes
Magnetic friction in Ising spin systems
A new contribution to friction is predicted to occur in systems with magnetic
correlations: Tangential relative motion of two Ising spin systems pumps energy
into the magnetic degrees of freedom. This leads to a friction force
proportional to the area of contact. The velocity and temperature dependence of
this force are investigated. Magnetic friction is strongest near the critical
temperature, below which the spin systems order spontaneously.
Antiferromagnetic coupling leads to stronger friction than ferromagnetic
coupling with the same exchange constant. The basic dissipation mechanism is
explained. If the coupling of the spin system to the heat bath is weak, a
surprising effect is observed in the ordered phase: The relative motion acts
like a heat pump cooling the spins in the vicinity of the friction surface.Comment: 4 pages, 4 figure
Giant Magnetoelectric Effect via Strain-Induced Spin-Reorientation Transitions in Ferromagnetic Films
It is shown theoretically that a giant magnetoelectric susceptibility
exceeding 10^-6 s/m may be achieved in the ferromagnetic/ferroelectric
epitaxial systems via the magnetization rotation induced by an electric field
applied to the substrate. The predicted magnetoelectric anomaly results from
the strain-driven spin-reorientation transitions in ferromagnetic films, which
take place at experimentally accessible misfit strains in CoFe2O4 and Ni films.Comment: 7 pages, 3 figure
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