804 research outputs found
Paisaje, cultura territorial y vivencia de la Geografía. Libro homenaje al profesor Alfredo Morales Gil
Tribute to Nieves López Martínez : Nieves López Martínez, passion for science
Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu
Compact Accelerator Design for a Compton Light Source
A compact electron accelerator suitable for Compton source applications is in design at the Center for Accelerator Science at Old Dominion University and Jefferson Lab. The design includes a KE=1.55 MeV low-emittance, optimized superconducting electron gun; a 23.45 MeV linac with multi-spoke 4.2 K superconducting cavities; and transport that combines magnetic longitudinal bunch compressor and transverse final focus. We report on the initial designs of each element, including end to end simulations with ASTRA and elegant, and expected beam parameters
New Results at JLab Describing Operating Lifetime of GaAs Photo-Guns
Polarized electrons from GaAs photocathodes have been key to some of the highest-impact results of the Jefferson Lab science program over the past 30 years. During this time, various studies have given insight into improving the operational lifetime of these photocathodes in DC high-voltage photo-guns while using lasers with spatial Gaussian profiles of typically 0.5 mm to 1 mm FWHM, cathode voltages of 100 kV to 130 kV, and a wide range of beam currents up to multiple mA. In this contribution, we show recent experimental data from a 100 kV to 180 kV setup and describe our progress at predicting the lifetime based on the calculable dynamics of ionized gas molecules inside the gun. These new experimental studies at Jefferson Lab are specifically aimed at exploring the ion damage of higher-voltage guns being built for injectors
Manual de diseño bioclimático urbano. Recomendaciones para la elaboración de normativas urbanísticas
O presente documento é o resultado de uma colaboração técnica em matéria de análise e desenho bioclimático dos espaços libres, realizada para o Instituto Politécnico de Bragança, dentro do Projeto BIOURB, no contexto do Programa de Cooperação Transfronteiriço Espanha – Portugal, desenvolvido como o apoio do Fundo Europeu de Desenvolvimento Regional (FEDER) e do Programa de Cooperação Portugal – Espanha (POCTEP). O trabalho foi desenvolvido entre 2012 e 2013 por investigadores do grupo GIAU+S de la UPM através do Instituto Juan de Herrera da ETSAM. Para a definição dos conteúdos, preparação de dados e tradução contribuíram também diversos investigadores do Centro de Investigação da Montanha (CIMO) do Instituto Politécnico de Bragança.El presente trabajo es el resultado de una asistencia técnica en materia de análisis y diseño bioclimático de los espacios libres realizada por encargo del del Instituto Politécnico de Bragança dentro del proyecto BIOURB, en el marco del Programa de Cooperación Transfronteriza España - Portugal que se desarrolla con el apoyo de la UE y la cofinanciación comunitaria de Fondo Europeo de Desarrollo Regional (FEDER) y el Programa de Cooperación Transfronteriza Portugal España (POCTEP). El trabajo fue realizado entre 2012 y 2013 por investigadores del GIAU+S de la UPM a través del Instituto Juan de Herrera de la ETSAM. Para la definición de los contenidos, aporte de datos y traducción contribuyeron además distintos investigadores del Centro de Investigação da Montanha (CIMO) del Instituto Politécnico de Bragança.POCTEP – Diversidad bioconstructiva transfronteriza, edificación bioclimática y su adaptación a la arquitectura y urbanismos moderno
Arsenolite: a quasi-hydrostatic solid pressure transmitting medium
This study reports the experimental characterization of the hydrostatic properties of arsenolite
(As4O6), a molecular solid which is one of the softest minerals in the absence of hydrogen
bonding. The high compressibility of arsenolite and its stability up to 15GPa have been
proved by x-ray diffraction measurements, and the progressive loss of hydrostaticity with
increasing pressure up to 20GPa has been monitored by ruby photoluminescence. Arsenolite
has been found to exhibit hydrostatic behavior up to 2.5GPa and a quasi-hydrostatic behavior
up to 10GPa at room temperature. This result opens the way to explore other molecular solids
as possible quasi-hydrostatic pressure-transmitting media. The validity of arsenolite as an
insulating, stable, non-penetrating and quasi-hydrostatic medium is explored by the study of
the x-ray diffraction of zeolite ITQ-29 at high pressure.This work has been performed with financial support from Spanish MINECO under projects MAT2013-46649-C4-2/3-P and MAT2015-71070-REDC. JAS acknowledges the 'Ramon y Cajal' fellowship program for financial support. We also thank D Calatayud, J J Garcia, T M Godoy, A Zapata, and A Cuenca for fruitful discussions. The authors thank ALBA light source for beam allocation at beamline MSPD. JLJ and FR acknowledge financial support through the SEV-2012-0267, Consolider Ingenio 2010-Multicat (CSD-2009-0050) and MAT2015-71842-P (MINECO/FEDER) projects.Sans-Tresserras, JÁ.; Manjón, FJ.; Popescu, C.; Muñoz, A.; Rodríguez-Hernández, P.; Jordá, JL.; Rey Garcia, F. (2016). Arsenolite: a quasi-hydrostatic solid pressure transmitting medium. Journal of Physics: Condensed Matter. 28(47):475403-1-475403-7. doi:10.1088/0953-8984/28/47/475403S475403-1475403-7284
Comparison of corneal morphologic parameters and high order aberrations in keratoconus and normal eyes
The aim of this study is evaluating the influence of corneal geometry in the optical system’s aberrations, and its usefulness as diagnostic criterion for keratoconus.159 normal eyes (normal group, mean age 37.8 ± 11.6 years) and 292 eyes with the diagnosis of keratoconus (keratoconus group, mean age 42.2 ± 17.6 years) were included in this study. All eyes received a comprehensive ophthalmologic examination. A virtual 3D model of each eye was made using CAD software and different anatomical parameters related with surface and volume were measured. Statistically significant differences were found for all anatomical parameters (all p < 0.001). AUROC analysis showed that all parameters reached values above 0.7, with the exception of the total corneal surface area (TCSAA-S). In conclusion, the methodology explained in this research, that bases in anatomical parameters obtained from a virtual corneal model, allow to analyze the diagnostic value of corneal geometry correlation with optical aberrations in keratoconus pathology.This publication has been carried out in the framework of the Thematic Network for Co-Operative Research in Health (RETICS), reference number RD16/0008/0012, financed by the Carlos III Health Institute–General Subdirection of Networks and
Cooperative Investigation Centers (R&D&I National Plan 2013–2016) and the European Regional Development Fund (FEDER)
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