Practical applications of the likelihood, time transcendence and metadata in virtual models of heritage elements

Contributed to: III Bienal de Restauración Monumental: "Sobre la des-restauración" (Sevilla, Spain, Nov 23-25, 2006)

Time transcendence, metadata and future utilization in 3D models of point clouds for heritage elements

Contributed to: Virtual Retrospect 2007 (Pessac, France, Nov 14-16, 2007)

Methodological keys for the acquisition and long-term use of photographic collections representing elements of Heritage

Contributed to: Fusion of Cultures. XXXVIII Annual Conference on Computer Applications and Quantitative Methods in Archaeology – CAA2010 (Granada, Spain, Apr 6-9, 2010)

The Metabolic Core and Catalytic Switches Are Fundamental Elements in the Self-Regulation of the Systemic Metabolic Structure of Cells

19 p.

Elements of Decision under Uncertainty with Applications

This work presents the basic elements for the analysis of decision under uncertainty: Expected Utility Theory and its citicisms and risk aversion and its measurement. The concepts of certainty equivalent, risk premium, absolute risk aversion and relative risk aversion, and the "more risk averse than" relation are discussed. The work is completed with several applications of decision making under uncertainty to different economic problems: investment in risky assets and portfolio selection, risk sharing, investment to reduce risk, insurance, taxes and income underreporting, deposit insurance and the value of information.

Studying the influence of substitutional elements on mechanical behavior of Alloy 718

In nickel-based superalloys, substitutional solute species have a strong impact on in service mechanical properties as well as on oxidation and corrosion resistances. In alloy 718, recent studies carried out by tensile tests highlighted the fact that refractory solute species are able to interact strongly with mobile dislocations during plastic deformation, generating dynamic strain ageing, and, in wide ranges of tests temperatures and strain rates, Portevin-Le Chatelier effect. The precise nature of the substitutional element responsible for such a dynamic interaction is still subject to debate. We addressed this question by means of mechanical spectroscopy studies of alloy 718 and various related alloys corresponding to monitored changes in the chemical composition. Only a single internal friction relaxation peak has been observed for all the studied alloys. By analyzing the damping behavior of these alloys at different imposed solicitation frequencies by sweeping a large temperatures range, the activation energies of the relaxation process and the type of mechanism involved have been determined. The process is a "Zener relaxation" in the alloys, i.e. a substitutional atoms dipole reorientation under applied stress. The results tend to prove that Niobium is not involved in the relaxation process whereas Molybdenum content seems to play an important role in the relaxation intensity.

From Gods to men: A historical overview of the discovery of the chemical elements

To achieve the apparently simple Periodic Table of the Elements has implied tremendous efforts over thousands of years. In this paper we present a brief history of the discovery of the chemical elements from prehistory to the present day, revealing the controversies that arose on the way and claiming the important work performed by alchemists in the advancement of knowledge. This is especially important if we consider that alchemy had a period of existence of many thousands of years, while the "Chemistry", officially established as a science in the eighteenth century, has operated as such for only a few hundred years. Even so, if we consider the progress of discovery and isolation of chemical elements throughout history, it can be observed that the number of elements identified is achieved mainly in the nineteenth and twentieth centuries, reflecting the development of instrumental techniques, that facilitated this task.

Geochemical characterization of the fire-fountain fed deposits of Las Herrerias volcano (Campo de Calatrava Volcanic Field, Ciudad Real)

The Las Herrerias volcano (Bolanos de Calatrava, Campo de Calatrava Volcanic Field) is characterized by the great amount and variety of fire-fountain fed deposits. All these deposits are compositionally similar, being constituted by magnesium-rich (MgO = 11.58-4.19%), aluminium-poor (Al2O3 = 9.64-10.99%) highly sodic (Na2O = 2.24-3.81%) melanephelinites, with high contents in rare earth-elements (10x-200x chondrite), particularly in light-rare earth elements with respect to the heavy ones [(La/Lu)(N) = 32-35]. Contrary to the equivalent melanephelinites of this volcanic field, the relatively low contents in Ni (233-286 ppm), Cr (393-520 ppm) and magnesium number (Mg* = 45-54) indicate that these rocks do not correspond with primary melts. On the other hand, the variable distribution of clinopyroxene in the magma during eruption would be responsible for the slight compositional differences observed in the studied samples. Finally, we argue that these fire fountains were developed in a continental intraplate setting.

Optimizing the Curie temperature of pseudo-binary RxR2-x ' Fe-17 (R, R ' = rare earth) for magnetic refrigeration

Several pseudo-binary RxR2-x'Fe-17 alloys (with R = Y, Ce, Pr, Gd and Dy) were synthesized with rhombohedral Th2Zn17-type crystal structure determined from x-ray and neutron powder diffraction. The choice of compositions was done with the aim of tuning the Curie temperature (T-C) in the 270 +/- 20 K temperature range, in order to obtain the maximum magneto-caloric effect around room temperature. The investigated compounds exhibit broad isothermal magnetic entropy changes, Delta S-M(T), with moderate values of the refrigerant capacity, even though the values of Delta S-M(Peak) are relatively low compared with those of the R2Fe17 compounds with R = Pr or Nd. The reduction on the Delta S-M(Peak) is explained in terms of the diminution in the saturation magnetization value. Furthermore, the Delta S-M(T) curves exhibit a similar caret-like behavior, suggesting that the magneto-caloric effect is mainly governed by the Fe-sublattice. A single master curve for Delta S-M/Delta S-M(Peak)(T) under different values of the magnetic field change are obtained for each compound by rescaling of the temperature axis.