Separador de fragmentos (F.R.S.) como herramienta para el análisis de reacciones nucleares a FAIR (FAcility for Antiproton and Ion Research in Europe)

Cada día la ciencia ha tenido que recurrir a la construcción de grandes instalaciones e instrumentos para realizar experimentos que permitan obtener información para que posteriormente sea analizada. En la física nuclear la creación de nuevas instalaciones ha venido creciendo a enormes pasos ya que para estudiar esta área de la física ha sido necesario construir aceleradores, espectrómetros magnéticos y detectores con el objetivo de obtener información experimental de sucesos a escala microscópica. En el presente artículo se hace una revisión acerca del proceso del diseño y construcción del espectrómetro de alta resolución magnética SUPER-FRS (Super-Fragment Separator) es resultado de una gran colaboración llamada FAIR en (Darmstadt) Alemania en las instalaciones del GSI con el fin de conocer la motivación científica que llevó a construirlo, su diseño técnico y trabajos que se han de realizar en él.Everyday science has had to resort to the construction of large facilities and instruments to carry out experiments that allow obtaining information so that it can be analyzed later. In nuclear physics, the creation of new facilities has been growing enormously since to study this area of physics it has been necessary to build accelerators, magnetic spectrometers and detectors in order to obtain experimental information of events on a microscopic scale. This article reviews the design and construction process of the SUPER-FRS (Super-Fragment Separator) magnetic high resolution spectrometer resulting from a great collaboration called FAIR in (Darmstadt) Germany in the GSI facilities with the In order to know the scientific motivation that led to build it, its technical design and work that has been done on it

Hydrogen Production by Steam Reforming of Ethanol on Rh-Pt Catalysts: Influence of CeO2, ZrO2, and La2O3 as Supports

CeO2-, ZrO2-, and La2O3-supported Rh-Pt catalysts were tested to assess their ability to catalyze the steam reforming of ethanol (SRE) for H2 production. SRE activity tests were performed using EtOH:H2O:N2 (molar ratio 1:3:51) at a gaseous space velocity of 70,600 h−1 between 400 and 700 °C at atmospheric pressure. The SRE stability of the catalysts was tested at 700 °C for 27 h time on stream under the same conditions. RhPt/CeO2, which showed the best performance in the stability test, also produced the highest H2 yield above 600 °C, followed by RhPt/La2O3 and RhPt/ZrO2. The fresh and aged catalysts were characterized by TEM, XPS, and TGA. The higher H2 selectivity of RhPt/CeO2 was ascribed to the formation of small (~5 nm) and stable particles probably consistent of Rh-Pt alloys with a Pt surface enrichment. Both metals were oxidized and acted as an almost constant active phase during the stability test owing to strong metal-support interactions, as well as the superior oxygen mobility of the support. The TGA results confirmed the absence of carbonaceous residues in all the aged catalysts.The authors are grateful to the Universidad de La Sabana and Universidad de Alicante for the financial support of this work

Design of a compact objective for SWIR applications

Lately the short-wave infrared (SWIR) has become very important due to the recent appearance on the market of the small detectors with a large focal plane array. Military applications for SWIR cameras include handheld and airborne systems with long range detection requirements, but where volume and weight restrictions must be considered. In this paper we present three different designs of telephoto objectives that have been designed according to three different methods. Firstly the conventional method where the starting point of the design is an existing design. Secondly we will face design starting from the design of an aplanatic system. And finally the simultaneous multiple surfaces (SMS) method, where the starting point is the input wavefronts that we choose. The designs are compared in terms of optical performance, volume, weight and manufacturability. Because the objectives have been designed for the SWIR waveband, the color correction has important implications in the choice of glass that will be discussed in detai

Stochastic optimal generation bid to electricity markets with emissions risk constraints

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/There are many factors that influence the day-ahead market bidding strategies of a generation company (GenCo) within the framework of the current energy market. Environmental policy issues are giving rise to emission limitation that are becoming more and more important for fossil-fueled power plants, and these must be considered in their management. This work investigates the influence of the emissions reduction plan and the incorporation of the medium-term derivative commitments in the optimal generation bidding strategy for the day-ahead electricity market. Two different technologies have been considered: the high-emission technology of thermal coal units and the low-emission technology of combined cycle gas turbine units. The Iberian Electricity Market (MIBEL) and the Spanish National Emissions Reduction Plan (NERP) defines the environmental framework for dealing with the day-ahead market bidding strategies. To address emission limitations, we have extended some of the standard risk management methodologies developed for financial markets, such as Value-at-Risk (VaR) and Conditional Value-at-Risk (CVaR), thus leading to the new concept of Conditional Emission at Risk (CEaR). This study offers electricity generation utilities a mathematical model for determining the unit's optimal generation bid to the wholesale electricity market such that it maximizes the long-term profits of the utility while allowing it to abide by the Iberian Electricity Market rules as well as the environmental restrictions set by the Spanish National Emissions Reduction Plan. We analyze the economic implications for a GenCo that includes the environmental restrictions of this National Plan as well as the NERP's effects on the expected profits and the optimal generation bid.Peer ReviewedPostprint (author's final draft

Stochastic optimal generation bid to electricity markets with emission risk constraints

There are many factors that influence the day-ahead market bidding strategies of a generation company (GenCo) in the current energy market framework. Environmental policy issues have become more and more important for fossil-fuelled power plants and they have to be considered in their management, giving rise to emission limitations. This work allows investigating the influence of the emission reduction plan, and the incorporation of the derivatives medium-term commitments in the optimal generation bidding strategy to the day-ahead electricity market. Two different technologies have been considered: the coal thermal units, high-emission technology, and the combined cycle gas turbine units, low-emission technology. The Iberian Electricity Market (MIBEL) and the Spanish National Emission Reduction Plan (NERP) defines the environmental framework to deal with by the day-ahead market bidding strategies. To address emission limitations, some of the standard risk management methodologies developed for financial markets, such as Value-at-Risk (VaR) and Conditional Valueat- Risk (CVaR), have been extended giving rise to the new concept of Conditional Emission at Risk (CEaR). This study offers to electricity generation utilities a mathematical model to determinate the individual optimal generation bid to the wholesale electricity market, for each one of their generation units that maximizes the long-run profits of the utility abiding by the Iberian Electricity Market rules, as well as the environmental restrictions set by the Spanish National Emissions Reduction Plan. The economic implications for a GenCo of including the environmental restrictions of this National Plan are analyzed, and the effect of the NERP in the expected profits and optimal generation bid are analyzed.Postprint (author’s final draft

Ventilator-associated Pneumonia After Elective Cardiac Surgery Caused by Pneumocystis Jirovecii

Ventilator-associated pneumonia is a severe complication among patients undergoing cardiac surgery. Although hospital-acquired bacterial pathogens, often multidrug resistant, are the most frequent cause, non-bacterial atypical and opportunistic agents traditionally associated with immunocompromise are increasingly recognized. We describe ventilator-associated pneumonia due to Pneumocystis jirovecii in the absence of traditional risk factors for Pneumocystis pneumonia in a patient after cardiac surgery

Los majos de Cádiz

El fenómeno del majismo tuvo en Cádiz singular efervescencia. Tanto durante el siglo XVIII como en el XIX, los personajes que encamaban aquellos rasgos y actitudes encontraron en la ciudad una atmósfera acorde para desenvolverse. No es sorprendente, por tanto, que cuando Armando Palacio Valdés decide darle voz narrativa al mundo popular gaditano centrase en esas figuras y en sus costumbres el argumento de una de sus novelas más difundidas. A pesar de los logros que la obra encierra, con su evocación del Cádiz decimonónico y sus ambientes más tradicionales, Los majos de Cádiz apenas había sido estudiada de manera aislada, resaltando su carácter testimonial y su valor como documento de la vida de determinados hombres y mujeres de la parte más meridional de la Baja Andalucía. Esta rigurosa edición preparada por Luis Fernández Cifuentes, profesor de la Universidad de Harvard, viene a colmar ese vacío, saldándose a sí mismo parte de la deuda contraída por la ciudad con el novelista asturiano