A series of low loading gold supported ceria/alumina catalysts have been prepared by the deposition-precipitation method, varying the pH of the synthesis. The catalysts were characterised by means of XRD, TEM, S BET , XRF and UV-Vis techniques, and their catalytic activity towards CO oxidation in the absence and in presence of water in the stream, were tested. It has been found that in this low loading gold catalysts, where the metallic particles are far away one from another and the oxygen transportation is not the limiting step of the reaction, the electronic properties of the ceria phase and the structure of the metal-support perimeter more than the diameter of the gold nanoparticles is the determinant factor in the catalytic performances of the solid.
Science, Technology, Engineering, and Mathematics (STEM) are key disciplines towards tackling the challenges related to the Sustainable Development Goals. However, evidence shows that women are enrolling in these disciplines in a smaller percentage than men, especially in Engineering related fields. As stated by the United Nations Women section, increasing the number of women studying and working in STEM fields is fundamental towards achieving better solutions to the global challenges, since the potential for innovation is larger. In this paper, we present the Girls4STEM project, which started in 2019 at the Escola Tècnica Superior d’Enginyeria de la Universitat de València, Spain. This project works towards breaking the stereotypes linked to STEM fields, addressing both boys and girls aged from 6 to 18, but especially trying to open the range of career options for young girls through interaction with female STEM experts. The goal is to spark girls’ interest in STEM disciplines from childhood, so that they become more self-confident in these areas. To achieve this goal, the project is built over three main actions: the Girls4STEM Family Talks, where students, families, and teachers participate; the Girls4STEM Professional Talks, where the target is a general audience; and the Initial Training Seminars for teachers. Short-term results are here presented, showing that aspects related to self-perception and perception from others (family, teachers) play a significant role. Moreover, these results also indicate that there may not be a general understanding of which disciplines are included in STEM.
Virtual modelling and 3D reconstruction are common tools used in the field of cultural heritage to recreate, analyse and visualise large objects (for example, archaeological sites and architectural buildings) and small objects such as sculptures, ceramic tiles or silver, marble and wooden artefacts. At present, it is possible to apply different technologies to achieve accurate photo-realistic 3D models. On the one hand, the precise modelling of existing 3D data is usually difficult and expensive as ''reality'' is complex per se; the more complex the object, the more complex the model. On the other hand, models are often achieved with the purpose of visualising the past state of monuments that nowadays are no longer fully conserved. In this sense, ''augmented reality'' (AR) technology can play an important role in cultural heritage. First, it permits the simultaneous viewing of both virtual and real 3D data. Second, the modelling of the entire object is no longer necessary. Third, it is possible to have full ''immersion'' of the viewer. This paper overviews the new technology of AR, as used in the world of cultural heritage to display past (now partially or totally lost) and present scenes together. It goes on to describe some practical experience of applying AR to the re-creation of two features, a Baroque vault and a Renaissance reredos, formerly present above the high altar of Valencia Cathedral in Spain.
Augmented Reality Technology
Definition and BenefitsThe terms 3D models and virtual reality (VR) are well known. In a virtual environment senses, such as sight, hearing and touch, are controlled by a computer, while actions influence the stimuli produced. In contrast to traditional VR systems, in AR the real environment is not completely suppressed, playing instead an important role (Bimber and Raskar, 2005). Its basic concept is to place computer-generated multimedia into the user's perception (usually field of The Photogrammetric Record
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.