La mineralización de Baritina de Purroy (Zaragoza, España)

The barite mineralization of Purroy (Zaragoza) is located in the Ordovician slates and sandstones, in the Structural Zone of Morata, the northern part of Unidad de Herrera (Eastern Iberian Chain). It is mainly composed of barite, quartz, goethite and hematite; fluorite and pirite with quartz and some Co-ore alteration minerals have also been recognized nearby. Although there is some filling-cavities barite, it occurs mainly in  NllOE veins, with an evident structural control; they present features of  contemporaneous mechanical deformation, related to prealpine distensive events. Barite occurs in a wide variety of aspects, very likely depending on the deposit conditions, and they bring out that at least some veins were filled in several stages, related with deformation events. Sr analysis in a cm scale shows an increase of Sr-content during the course of deposition; in a vein scale this pattern is alterated by mecanic deformations, disolutions and reprecipitations, related with a polyphasic deposit process. Analysis of trace elements suggest a geochemical influence of the environment on the formation of the barite deposit. Fe, Co & Mn are the most characteristic trace elements in this barite mineralization, and their patterns are partialy linked to barite precipitation conditions

Programa de cálculo de las constantes ópticas de materiales opacos en Fortran IV

Cuando se desea calcular las constantes ópticas n, k a partir de las medidas de reflectancia en aire y aceite de inmersión, es necesario manejar gran cantidad de datos experimentales, sobre todo si se pretende construir las curvas de dispersión de estas constantes desde los 400 nm a los 1.100 nm, efectuando series de 100 lecturas cada 10 nm. Para manejar esta gran cantidad de datos se propone el programa denominadaIRCA escrito en FORTRAN IV para utilizar con computadoras IBM modelos 1130 o 360

Los basaltos alcalinos subvolcánicos espilitizados de Arándiga (provincia de Zaragoza): estudio mineralógico y geoquímico

Diversos sills subvolcanicos. aflorantes en el área de Arándig-a (Zaragoza) se emplazan en sedimentos pertenecientes al transito del Keuper al Rhetiense-Hettangiense. Corresponden a basaltos alcalinos cuyos minerales primarios (olivino, piroxeno, plagioclasa) se han transformado en albita-oligoclasa, ortosa, clorita, clorita-esmectita, carbonatos, etc. Es característica de los sills una zonación petrográfica reconocible en sus propiedades texturales y asociaciones minerales. La composici6n química de estas rocas ha experimentado asimismo importantes modificaciones. Las pautas de variación de los elementos incompatibles indican una pequeiia diferenciación magmiítica. Tiene notable afinidad con rocas, de an6loga composici6n y edad, aflorantes en..otros sectores de la Cadena Ibérica. Según ha sido expuesto por diversos autores, representa una provincia alcalina que, con edad Trias-Lias, esta asociado a un rifting intracontinental que afecta al borde occidental del Tethys

Universal imprinting of chirality with chiral light by employing plasmonic metastructures

Chirality, either of light or matter, has proved to be very practical in biosensing and nanophotonics. However, the fundamental understanding of its temporal dynamics still needs to be discovered. A realistic setup for this are the so-called metastructures, since they are optically active and are built massively, hence rendering an immediate potential candidate. Here we propose and study the electromagnetic-optical mechanism leading to chiral optical imprinting on metastructures. Induced photothermal responses create anisotropic permittivity modulations, different for left or right circularly polarized light, leading to temporal-dependent chiral imprinting of hot-spots, namely imprinting of chirality. The above effect has not been observed yet, but it is within reach of modern experimental approaches. The proposed nonlinear chiroptical effect is general and should appear in any anisotropic material; however, we need to design a particular geometry for this effect to be strong. These new chiral time-dependent metastructures may lead to a plethora of applications.Comment: Main (29 pages, 6 figures) and supplemental (46 pages, 35 figures

Plasmonic nanocrystals with complex shapes for photocatalysis and growth: Contrasting anisotropic hot-electron generation with the photothermal effect

In plasmonics, and particularly in plasmonic photochemistry, the effect of hot-electron generation is an exciting phenomenon driving new fundamental and applied research. However, obtaining a microscopic description of the hot-electron states represents a challenging problem, limiting our capability to design efficient nanoantennas exploiting these excited carriers. This paper addresses this limitation and studies the spatial distributions of the photophysical dynamic parameters controlling the local surface photochemistry on a plasmonic nanocrystal. We found that the generation of energetic electrons and holes in small plasmonic nanocrystals with complex shapes is strongly position-dependent and anisotropic, whereas the phototemperature across the nanocrystal surface is nearly uniform. Our formalism includes three mechanisms for the generation of excited carriers: the Drude process, the surface-assisted generation of hot-electrons in the sp-band, and the excitation of interband d-holes. Our computations show that the hot-carrier generation originating from these mechanisms reflects the internal structure of hot spots in nanocrystals with complex shapes. The injection of energetic carriers and increased surface phototemperature are driving forces for photocatalytic and photo-growth processes on the surface of plasmonic nanostructures. Therefore, developing a consistent microscopic theory of such processes is necessary for designing efficient nanoantennas for photocatalytic applications

Extreme weather events and the energy sector in 2021

In 2021, the energy sector was put at risk by extreme weather in many different ways: North America and Spain suffered heavy winter storms that led to the collapse of the electricity network; California specifically experienced heavy droughts and heatwave conditions, causing the operations of hydropower stations to halt; floods caused substantial damage to energy infrastructure in central Europe, Australia and China throughout the year, and unusual wind drought conditions decreased wind power production in the United Kingdom by almost 40% during summer. The total economic impacts of these extreme weather events are estimated at billions of USD. Here we review and assess in some detail the main extreme weather events that impacted the energy sector in 2021 worldwide, discussing some of the most relevant case studies and the meteorological conditions that led to them. We provide a perspective on their impacts on electricity generation, transmission and consumption, and summarize estimations of economic losses

Hot electrons and electromagnetic effects in the broadband Au, Ag, and Ag-Au nanocrystals: The UV, visible, and NIR plasmons

Energetic and optical properties of plasmonic nanocrystals strongly depend on their sizes, shapes, and composition. Whereas using plasmonic nanoparticles in biotesting has become routine, applications of plasmonics in energy are still early in development. Here, we investigate hot electron (HE) generation and related electromagnetic effects in both mono- and bi-metallic nanorods (NRs) and focus on one promising type of bi-metallic nanocrystals - core-shell Au-Ag nanorods. The spectra of the NRs are broadband, highly tunable with their geometry, and have few plasmon resonances. In this work, we provide a new quantum formalism describing the HE generation in bi-metallic nanostructures. Interestingly, we observe that the HE generation rate at the UV plasmon resonance of Au-Ag NRs appears to be very high. These HEs are highly energetic and suitable for carbon-fuel reactions. Simultaneously, the HE generation at the longitudinal plasmon (L-plasmon) peaks, which can be tuned from the yellow to near-IR, depends on the near-field and electromagnetic Mie effects, limiting the HE efficiencies for the long and large NRs. These properties of the L-plasmon relate to all kinds of NRs (Au, Ag, and Au-Ag). We also consider the generation of the interband d-holes in Au and Ag, since the involvement of the d-band is crucial for the energetic properties of UV plasmons. The proposed formalism is an important development for the description of bi-metallic (or tri-metallic, or more complex) nanostructures, and it paves the way to the efficient application of the plasmonic HEs and hot holes in sensing, nanotechnology, photocatalysis, and electrophotochemistry