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A radiative transfer model for the determination of UV radiation on arbitrarily oriented surfaces is validated by spectral measurements taken directly on the inner surface of a cockpit window of an Airbus A321-231 during a flight from Frankfurt, Germany to Málaga, Spain on 23 August, 2018. The simulations consider the UV spectral range from 290 nm to 400 nm and take into account both the measured spectral transmittance of a cockpit window as well as its construction-related orientation. Comparisons are performed for selected route segments with largely cloud-free conditions. The cruising level of the Airbus on these segments was nearly constant between 11.27 km and 11.29 km. UV irradiance measurements at the cockpit window give values within a range of 19 W/m2 and 26 W/m2. The comparison of modelled and measured irradiances show a very good agreement, i.e. the relative differences between simulated and measured values range from -2.1 % to +4.3 %. In addition, horizontally and vertically oriented sensors are simulated for the same flight. The validation results generally underpin the application potential of the model. As an example of this, UV irradiances incident on differently oriented surfaces, as could occur inside and outside of a future flying taxi on a short-haul flight between Munich and Augsburg at low cruising level, are shown.

A device is proposed for the measurement of diffuse solar irradiance on tilted surfaces pointing-to as well as fixed on the equatorial direction. Most commercial devices are not designed for this purpose. Here, we present a specific design for a system based on a single multi-lobe shadow-ring that allows us to measure diffuse irradiance with several tilted pyranometers – from 60 to 90 degrees from the horizontal plane – and on different azimuth angles. This first prototype allows us to measure in the four cardinal directions. The ring is designed to minimize the covered celestial dome observed by each sensor. Moreover, the complete device needs a very small installation area and its simplicity means it is inexpensive and easy to operate. The measurements have subsequently to be corrected with a geometrical correction factor that takes into account the portion of the sky vault blocked by the shadow-ring. These measurements are essential for estimating solar potential on tilted surfaces – such as building façades – and for improving current anisotropic solar models, among many other applications., Spanish Government (grant ENE2011-27511)

The electrochemical behavior of ethylene electrooxidation on preferentially oriented Au surfaces is investigated in 1 M H2 SO4 aqueous solution at 25°C. A symmetric square wave periodic potential signal is applied to polycrystalline Au electrodes to obtain (111)-, (110)-, and (100)-type oriented surfaces, which are characterized by cyclic voltammograms and SEM micrographs. It is found that ethylene adsorbs at potentials just below the potential of zero charge of the Au/1 M H2 SO4 interface, and two residues are detected in an anodic stripping experiment. The adsorbed ethylene voltammetric electrooxidation, and the bulk ethylene anodic polarization curves are measured at the differently oriented Au surfaces. O comportamento eletroquímico na oxidação do etileno em superfícies de Au preferencialmente orientado é investigado em solução aquosa 1 M H2SO4 a 25°C. Uma onda quadrada de potencial simétrica e periódica é aplicada a eletrodos policristalinos de Au para obter superfícies orientadas dos tipos (111), (110) e (100), as quais são caracterizadas por voltamogramas cíclicos e micrografias SEM. É comprovado que o etileno se adsorve em potenciais ligeiramente inferiores ao potencial de carga zero da interface Au/1 M H2SO4, e dois resíduos são detectados num experimento de "stripping" anódico. A eletro-oxidação voltamétrica do etileno adsorvido e as curvas de polarização anódicas do etileno no meio da solução são medidas nas diferentes superfícies orientadas do Au.