Passivity Breakdown of Titanium in LiBr solutions

The passive behavior of titanium and its susceptibility to undergo localized attack in different LiBr solutions at 25 degrees C have been investigated using different electrochemical techniques: potentiodynamic polarization curves, potentiostatic passivation tests, EIS measurements and Mott-Schottky analysis. In low and moderately concentrated LiBr solutions, the breakdown potential E-b decreased with increasing bromide concentrations, while in highly concentrated LiBr solutions, E-b increased with increasing LiBr concentration. In the most concentrated LiBr solution (11.42M) Ti did not undergo passivity breakdown even at 9 V-Ag/AgCl. This observation can be explained by a a decrease in the activity of water in highly concentrated LiBr solutions. (C) 2013 The Electrochemical Society.We wish express our gratitude to the Ministerio de Ciencia e Innovacion (Project CTQ2009-07518), and to Dr. M. Asuncion Jaime. for her translation assistance.Fernández Domene, RM.; Blasco-Tamarit, E.; García-García, D.; García Antón, J. (2014). Passivity Breakdown of Titanium in LiBr solutions. Journal of The Electrochemical Society. 161(1):25-35. https://doi.org/10.1149/2.035401jesS25351611Been J. Grauman J. S. , in: Uhlig's Corrosion Handbook, 2nd ed., Winston Revie R. (ed.), 863-885, Wiley Interscience, New York (2000).Blasco-Tamarit, E., Igual-Muñoz, A., García Antón, J., & García-García, D. (2007). Corrosion behaviour and galvanic coupling of titanium and welded titanium in LiBr solutions. Corrosion Science, 49(3), 1000-1026. doi:10.1016/j.corsci.2006.07.007Huang, Y. Z., & Blackwood, D. J. (2005). Characterisation of titanium oxide film grown in 0.9% NaCl at different sweep rates. Electrochimica Acta, 51(6), 1099-1107. doi:10.1016/j.electacta.2005.05.051Pan, J., Thierry, D., & Leygraf, C. (1996). 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High radon levels in subterranean environments: monitoring and technical criteria to ensure human safety (case of Castañar cave, Spain)

Castañar cave contains the highest radon gas (222Rn) concentration in Spain with an annual average of 31.9 kBq m−3. Seasonal variations with summer minimums and maximum values in fall were recorded. The reduction of air-filled porosity of soil and rock by condensation or rainfalls hides the radon exchange by gas diffusion, determining this seasonal stair-step pattern of the radon activity concentration in underground air. The effective total dose and the maximum hours permitted have been evaluated for the guides and public safety with a highly detailed radon measurement along 2011 and 2012. A network of 12 passive detectors (kodalphas) has been installed, as well as, two radon continuous monitoring in the most interesting geological sites of the subterranean environment.A follow up of the recommended time (max. 50 min) inside the underground environment has been analysed since the reopen to public visitors for not surpassing the legal maximum effective dose for tourists and guides. Results shown that public visitors would receive in fall a 12.1% of the total effective dose permitted per visit, whereas in summer it is reduced to 8.6%, while the cave guide received a total effective dose of 6.41 mSv in four months.The spatial radon maps allow defining the most suitable touristic paths according to the radon concentration distribution and therefore, appropriate fall and summer touristic paths are recommended.This research was funded by the Regional Government of Extremadura (Spain) through EAFRD Axis 2 “Improving the environment and the countryside” and the Spanish Ministry of Economy and Competitiveness through project CGL2013-43324R and the programme Torres Quevedo (PTQ 13-06296 and PTQ 12-05601).A.F-C is funded by an IEF Marie Curie Action (FP7/2007–2013) under REA grant agreement n° 624204Peer reviewe

Inverse Opal CuCrO2 Photocathodes for H2 Production Using Organic Dyes and a Molecular Ni Catalyst.

Dye-sensitized photoelectrochemical (DSPEC) cells are an emerging approach to producing solar fuels. The recent development of delafossite CuCrO2 as a p-type semiconductor has enabled H2 generation through the coassembly of catalyst and dye components. Here, we present a CuCrO2 electrode based on a high-surface-area inverse opal (IO) architecture with benchmark performance in DSPEC H2 generation. Coimmobilization of a phosphonated diketopyrrolopyrrole (DPP-P) or perylene monoimide (PMI-P) dye with a phosphonated molecular Ni catalyst (NiP) demonstrates the ability of IO-CuCrO2 to photogenerate H2. A positive photocurrent onset potential of approximately +0.8 V vs RHE was achieved with these photocathodes. The DPP-P-based photoelectrodes delivered photocurrents of -18 μA cm-2 and generated 160 ± 24 nmol of H2 cm-2, whereas the PMI-P-based photocathodes displayed higher photocurrents of -25 μA cm-2 and produced 215 ± 10 nmol of H2 cm-2 at 0.0 V vs RHE over the course of 2 h under visible light illumination (100 mW cm-2, AM 1.5G, λ > 420 nm, 25 °C). The high performance of the PMI-constructed system is attributed to the well-suited molecular structure and photophysical properties for p-type sensitization. These precious-metal-free photocathodes highlight the benefits of using bespoke IO-CuCrO2 electrodes as well as the important role of the molecular dye structure in DSPEC fuel synthesis

Marine GIS Applications: GIS Spanish Institute of Oceanography

Poster presentado en el SIEBM XVIII Simposio Ibérico de Biología MarinaSince 1998 in the IEO is developing a MARINE GIS with the objective of organize, harmonize, standardize, integrated the geo-information of IEO. GIS tools are used in several projects carried out in the IEO related to study of living resources, natural resources, studies of evolution of natural phenomena, collecting data, marine spatial planning, etc

The prevalence of depression, anxiety and stress and their associated factors in college students

Aim: To estimate the prevalence of symptoms of depression, anxiety, stress and associated factors in a population of college students. Method: Cross-sectional study of psychological distress measured through the Depression, Anxiety and Stress Scale (DASS-21) in a sample of 1074 college students. Results: We found a moderate prevalence of depression (18, 4%), anxiety (23, 6%) and stress (34, 5%) symptoms in our study population. Being <21, having problematic Internet use behavior, smoking, presenting insomnia and having a low self-esteem were independently associated with symptoms of depression, anxiety and stress. Being a woman, living with their family, having a stable partner, consuming alcohol frequently and having poor nutritional habits were significantly associated with symptoms of stress; lacking a stable partner was significantly associated with depressive symptoms; and frequent consumption of alcohol was significantly associated with symptoms of anxiety. Conclusion: We found a moderate prevalence of depression, anxiety and stress symptoms in our population. Interventions aimed at promoting mental health among college students should be implemented

Iberian pig efficiency peeling acorns

A functional character of Iberian pigs is their efficiency peeling acorns. This is analized with Iberian pigs on a sample of 40 evergreen oaks. The result is showed as percentage of pulp DM refuse and pulp weigh refuse (18.94±1.19% versus 0.53±0.04 g) with a high variation likely influenced by morphology and weight differences between acorns.Una de las características funcionales del cerdo Ibérico es su eficiencia al pelar las bellotas. Ésta se analiza a partir de cerdos Ibéricos y sobre muestras de 40 encinas. El resultado obtenido, porcentaje de desperdicio de MS de pulpa y peso de la MS de pulpa desperdiciada por bellota (18,94±1,19% versus 0,53±0,04 g) presenta una alta variación previsiblemente influenciada por las diferencias de la morfología y peso de las bellotas

Ultrasonography detection of pregnancy in outdoor iberian sows

In a flock of pure Iberian sows, with outdoor breeding and total freedom, ultrasonography detection of pregnancy length is studied (11.1±0.6 seconds), according to pregnancy or not pregnancy (9.7 vs 20.4 seconds). Also, possible influence of cycle number is analysed. By other side permanence of ear tags after a year is valued (99.5%). Results show that indoor and intensive production is not justified in order to attain more reproductive control.En un rebaño de cerdas Ibéricas puras, criadas en régimen de total libertad (sin empleo de jaulas), se estudia el tiempo empleado en el diagnóstico de gestación con ecógrafo (11,1±0,6 segundos por cerda), se analiza la duración del diagnóstico dependiendo de si hay preñez o no (9,7 vs 20,4 segundos) y la posible influencia del número de ciclo. Por otra parte se valora la permanencia de los crotales de identificación individual tras un año (99,5%). Los resultados indican que la intensificación de la producción en esta raza no está justificada por la consecución de un mayor control reproductivo

Habitat selection in terrestrial snails and its applications to heliciculture

Snails are employed as experimental animals in different scientific fields and their growth is a good biological indicator. Growth is mainly determined at a genetic level, although many factors biotic and abiotic may alter growth rates. One of these factors is habitat selection. Nevertheless the knowledge about the cha-racteristics that determines habitat selection are not considered in the design of installations, management of farms or raising snails. In this way, the aim of this paper is synthesize the different components of habitat that influence habitat choice of terrestrial snails. On the other hand, it proposes premises that would be considered in design of installations.El crecimiento de los caracoles terrestres que, además de como animales productivos, se utilizan como animales de experimentación es considerado un buen indicador biológico. Aunque el crecimiento está genéticamente determinado, muchos factores pueden modificarlo, uno de ellos es la selección de hábitat. Sin embargo, los conocimientos sobre las condiciones que la determinan no se suelen incorporar al diseño de instalaciones, manejo de los criaderos o la producción helicícola. En este trabajo se revisan aquellas condiciones que determinan la selección de microhábitat en caracoles terrestres y se proponen medidas que deberían ser consideradas en el diseño de instalaciones

Carcass and meat quality in light lambs in the segureña breed

Meat and carcass quality were studied in 124 Segureña breed lambs, 62 males and 62 females, slaughtered at the market weight, of 19-25 kg. Carcasses, with a yield between 48 percent (CCW/SW) and 55 percent (HCW/EW), were qualified for the most part in the 2 class of conformation as a fairly fatty, of 2/3 covered kidney and pink color muscle. There were differences among sexes for the fatness scores. The pelvic limb represents the 33.6 percent of the carcass, the shoulder 19.5 percent, the ribs+loin 17.7 percent, the breast 11.1 percent, the neck 7.3 percent, and the anterior ribs 6.7 percent; for commercial categories 58.1 percent pertained to the first category, 19.5 percent to the second and 19.8 percent to the third. Carcass were formed by 19.9 percent of fat, 52.7 percent muscle and 19.2 percent bone; these values show an ideal degree of fatness, in the local market. The sex had a significant effect on the percentage of fat and bone of the carcass. The average pH values, 6.6 and 6.5, following the preparation of the carcass for m. longissimus dorsi and m. triceps, decreased to 5.8 and 5.9, respectively, at 24 hours post mortem. These muscles presented a water holding capacity of 16.4 and 9.9 percent, and a tenderness of 3866 and 3945 g/cm2. The haem pigments and the color of m. longissimus dorsi and m. rectus abdominis confirm the results of its subjective evaluation.Se estudiaron características de calidad de la canal y de la carne en 124 corderos, 62 machos y 62 hembras, de raza Segureña sacrificados a peso de mercado, 19-25 kg. Las canales, con rendimientos entre el 48 p.100 (PCF/PVS) y el 55 p.100 (PCC/PVV), son de conformación normal (nota 2), medianamente grasas, de riñón cubierto 2/3 y músculo de color rosa; registrándose diferencias entre sexos para las calificaciones de engrasamiento. Al despiece, la pierna representó el 33,6 p.100 de la canal, la espalda el 19,5 p.100, el costillar el 17,7 p.100, los bajos el 11,1 p.100, el cuello el 7,3 p.100 y el badal el 6,7 p.100; lo que por categorías comerciales supone el 58,1 p.100 para las de 1ª, el 19,5 p.100 y 19,8 p.100 para las de 2ª y 3ª, respectivamente. La canal contenía 19,9 p.100 de grasa, 52,7 p.100 de músculo y 19,2 p.100 de hueso lo que muestra su buen grado de acabado. El sexo afectó significativamente al porcentaje de grasa y hueso de la canal. Los valores iniciales de pH, 6,6 y 6,3 para m. longissimus dorsi y m. triceps brachii, descienden a 5,8 y 5,9 a las 24 horas post mortem, respectivamente. La capacidad de retención de agua de estos músculos fue de 16,4 y 9,9 p.100 y su dureza media 3866 y 3945 g/cm2. El pigmento hemínico y el color de m. longissimus dorsi y m. rectus abdominis confirman la valoración subjetiva del color de la carne