Search results for "alum"
showing 10 items of 1303 documents
Physico-Chemical Characterization of Ta2O5 Thin Films/Electrolyte Junctions
2007
An analysis of the electronic properties of Ta2O5 / electrolyte junction is reported for thin film (≤ 14 nm) grown on tantalum in acidic electrolyte. The investigation is carried out by the synergetic use of three techniques: Photocurrent Spectroscopy (PCS), Electrochemical Impedance Spectroscopy (EIS) and Differential Admittance (DA) measurements. PCS is a non destructive optical technique based on the analysis of the electrochemical response (photocurrent or photopotential) of the electrode/electrolyte interface under irradiation with photons of suitable energy. PCS can provide information on the energetic of metal/oxide/electrolyte interfaces (flat band potential determination, conductio…
Representative major element compositions of clinopyroxenes and phlogopites from ultrapotassic rocks from Nangqian basin (Eastern Tibet)
2020
Representative major element compositions (in wt%) of clinopyroxenes and phlogopites from Nangqian ultrapotassic rocks. In-situ major-element compositions of mineral phases were obtained using the JEOL JXA-8230 Electron Microprobe at ISTerre, University Grenoble Alpes. Analytical conditions were 15 kV accelerating voltage and 12 nA beam current. The ZAF procedure was applied to reduce the raw data. The microprobe was calibrated using natural and synthetic standards. An X-ray element map of a calcite-bearing aggregate was acquired using 15 kV accelerating voltage and 10 nA beam current.
La transición española : ¿qué sabe el alumnado de 1º de bachillerato?
2020
El presente artículo es el resultado del análisis de una encuesta realizada a 79 estudiantes de 1º de Bachillerato sobre la transición española. Mediante esta investigación se quiere acreditar, con metodología cuantitativa, los conocimientos e ideas que el alumnado encuestado tiene acerca de ese periodo histórico tras la realización de la Educación Secundaria. Para ello se ha realizado una encuesta con variedad de preguntas entre las cuales se han incluido algunas relacionadas entre sí para comprobar posibles contradicciones en las respuestas. La encuesta abarca diferentes cuestiones: desde personajes históricos hasta actores más globales como diferentes organizaciones o movilizaciones soci…
Noncontact Air-Coupled Guided Wave Ultrasonics for Detection of Thinning Defects in Aluminum Plates
2001
Ultrasonic guided waves are gaining increasing attention for the inspection of platelike and rodlike structures. At the same time, inspection methods that do not require contact with the test piece are being developed for advanced applications. This paper capitalizes on recent advances in the areas of guided wave ultrasonics and noncontact ultrasonics to demonstrate a superior method for the nondestructive detection of thinning defects simulating hidden corrosion in thin aluminum plates. The proposed approach uses micromachined gas (air)-coupled capacitive transducers for the noncontact generation and detection of guided plate waves. Interesting features in the dispersive behavior of select…
Energy and CO2 life cycle inventory issues for aluminum based components: The case study of a high speed train window panel
2016
Abstract As materials production and transport are two relevant sectors in terms of global environmental impact, over the last years environmental impact analyses (mainly life cycle based analyses) of material replacing strategies in means of transportation were developed. Life cycle approach allows to consider the light-weighing benefit without neglecting the environmental impact of material production. In the present research energy and CO2 emissions life cycle analysis of a real case study is presented. Industrial data, experimental measurements and literature analysis were used to develop the life cycle analysis of an aluminum window panel to be assembled on an Italian high speed train.…
Self-piercing riveting for aluminium alloys-composites hybrid joints
2008
In the paper, the growing interest on hybrid joints developed between composite panels and aluminium alloys blanks is focused. The self-piercing riveting operation is considered and its feasibility for the proposed joints verified. The most relevant process parameters were investigated in order to determine a suitable process window and, what is more, the mechanical performances of the developed joints were investigated in order to determine process parameters aimed to maximise them. Finally, the failure mechanics of the obtained joints were considered in order to highlight the mechanisms which occur and determine the lost of the load carrying capability of the joints. The developed experim…
On the FSW of AA2024-T4 and AA7075-T6 T-joints: an industrial case study
2009
In this paper, the authors present the results of a wide experimental campaign on aeronautical T-shaped parts of industrial interest characterized by dissimilar materials for the skin and stringer. The friction stir welding process engineering was developed with the aim to determine the specific process parameters determining the soundness on the obtained T-parts both from the metallurgical and mechanical point of view. Furthermore, the performance of the obtained T-joints was investigated.
Magister : revista de formación del profesorado e investigación educativa
2016
La competencia colaborativa es una herramienta muy útil para el alumnado universitario. La diversidad de ámbitos profesionales que existen hoy en día demanda unos trabajadores competentes que se adapten a una realidad laboral compleja y cambiante. En este sentido, las relaciones interpersonales cobran gran importancia al requerir la colaboración entre profesionales para conseguir un objetivo final. El presente artículo describe una propuesta de trabajo colaborativo que se llevó a cabo con el alumnado universitario del cuarto curso de Magisterio de la Universitat de València que cursaban el itinerario de especialización en Educación Musical. Collaborative competition is a very useful tool fo…
2020
The reaction of the copper(I) β-diketiminate copper complex {(Cu(BDIMes))2(μ-C6H6)} (BDIMes = N,N'-bis(2,4,6-trimethylphenyl)pentane-2,4-diiminate) with the low-valent group 13 metal β-diketiminates M(BDIDip) (M = Al or Ga; BDIDip = N,N'-bis(2,6-diisopropylphenyl)pentane-2,4-diiminate) in toluene afforded the complexes {(BDIMes)CuAl(BDIDip)} and {(BDIMes)CuGa(BDIDip)}. These feature unsupported copper-aluminum or copper-gallium bonds with short metal-metal distances, Cu-Al = 2.3010(6) A and Cu-Ga = 2.2916(5) A. Density functional theory (DFT) calculations showed that approximately half of the calculated association enthalpies can be attributed to London dispersion forces.
Comparing analytical methods to detect SARS-CoV-2 in wastewater
2021
Wastewater based epidemiology (WBE) has emerged as a reliable strategy to assess the coronavirus disease 2019 (COVID-19) pandemic. Recent publications suggest that SARS-CoV-2 detection in wastewater is technically feasible; however, many different protocols are available and most of the methods applied have not been properly validated. To this end, different procedures to concentrate and extract inactivated SARS-CoV-2 and surrogates were initially evaluated. Urban wastewater seeded with gamma-irradiated SARS-CoV-2, porcine epidemic diarrhea virus (PEDV), and mengovirus (MgV) was used to test the concentration efficiency of an aluminum-based adsorption-precipitation method and a polyethylene…