5 research outputs found
Neandertales en el valle del Lozoya: los yacimientos paleolíticos del Calvero de la Higuera (Pinilla del Valle, Madrid)
Se presenta el estudio de un conjunto de yacimientos del Pleistoceno superior situados en un complejo kárstico en el valle alto del Lozoya (Pinilla del Valle, Madrid). El abrigo de Navalmaíllo conserva restos de industria lítica, hogares, y fauna altamente antropizada, común en lugares de habitación. La cueva de la Buena Pinta, se utilizó preferentemente como cubil de hienas, aunque la presencia esporádica de industria lítica de entidad, como núcleos y percutores, apunta a una cierta actividad humana. La cueva del Camino y el abrigo del Ocelado funcionaron como cubiles de hiena. Por último, la cueva Des-cubierta, presenta evidentes indicios de actividad humana pero aún se encuentra en una fase preliminar de estudio
EP-1349: Acute skin toxicity of hypofractionated whole breast radiotherapy in large-breasted patients
Evaluation of encapsulation and passivation of InGaAs/InP DHBT devices for long-term reliability
Dry-etch fabrication of reduced area InGaAs/InP DHBT devices for high speed circuit applications
Vanadium characterization in BTO: V sillenite crystals
Visible and Infrared Optical Absorption and Electron Paramagnetic Resonance (EPR) techniques have been used to characterize the intrinsic defects in sillenite type crystals: nominally pure Bi12TiO20 (BTO) and doped with vanadium (BTO:V). Optical quality crystals, with the composition Bi12.04±0.08Ti0.76±0.07V0.16±0.02O20, have been grown. Results obtained by these different techniques have shown unambiguously the 5+ valence state of the vanadium ion in BTO:V crystals. In pure BTO samples, the EPR and optical spectra show strong evidence of the presence of the intrinsic defect BiM3+ + ho+, which consists of a hole h+, mainly located on the oxygen neighbors of the tetrahedrally coordinated Bi3+ ion. After doping with vanadium, results have shown that the characteristic bands, associated to this hole defect center, disappear, suggesting its transformation in single Bi3+. Anisotropy of the EPR spectra , at 20 K, is related to Fe3+ impurities