87,467 research outputs found
Efficienza energetica degli edifici scolastici pugliesi: un’indagine basata sulla rilevazione dei consumi reali
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Sviluppo di una piattaforma computazionale interattiva per la simulazione di involucri responsivi ad alte prestazioni in diversi scenari climatici tipici e futuri
No full textMany researchers have recently developed new responsive technologies to improve the interaction between the mutable external environment and the building. These systems can react to external stimuli – e.g., outdoor temperature, solar radiation, etc. – changing their properties – solar,
thermal, geometrical, etc. – to reduce the energy demand and the users’ discomfort. Despite a
large number of studies propose new responsive technologies, these devices are still not widespread and the reason of this mismatch between theoretical technological studies and practical
applications is probably due to a lack of simple and easy-to-use energy analysis tools. The intrinsic complexity of many of these systems requires a specific knowledge and – depending on the
specific technology – could require also additional external algorithms to run energy analyses.
The aim of this work is to provide an interactive tool that allows to simplify the modelling and
simulation phase, giving as final output a reliable comparison between traditional and responsive
technologies. From a technical point of view, the platform is based on EnergyPlus as simulation
engine, Python as simulation and file manager, and Grasshopper as graphical interface. The file
management, the modelling and the simulation are completely automated; hence, the users work
only on Grasshopper simply inputting through pop-up menus the key information (context, technology, control strategy). The users can select between different responsive technologies and,
considering their dependance on the weather conditions, the users can test them in 25 different
European cities. Similarly, three different climate scenarios (current, 2050, 2080) can be selected
to evaluate if the responsiveness of these systems can be helpful also in future scenarios to improve the building resilience to climate change. This paper describes the structure of the platform
developed and tests its reliability and potential on an electrochromic applicatio
Silica shelling of Quantum Dots and gold film development
No full textColloidal Quantum Dots (QDs) are an established class of optoelectronic materials thanks to their tunable and highly efficient emission. The encapsulation of QDs in silica shells is a well-known procedure to protect them from the external environment and obtain dispersibility in polar solvents. Here, we have coated different types of QDs (CdSe@CdS [1] and InP@ZnS [2]) with silica shells of controlled thickness. The silica shells were obtained exploiting the Reverse Microemulsion reaction combined with an experimental design approach [3,4]. In addition to this, we deposited a uniform gold film over the silica shell. The combination of the QDs emission with the gold plasmon resonance enables an improvement in the optical properties, as already demonstrated [5]. As a first step to achieve this goal, the functionalization of the silica shell for further gold seeds attachment is required. With such aim, we employed (3-Aminopropyl)trimethoxysilane (APTMS), with an amino group binding to the gold seed, helping in the development of the film. Instead, the silicon of the APTMS binds strongly to the silica surface through a covalent bond. Thanks to the 1H and two-dimensional NOESY (Nuclear Overhauser Effect Spectroscopy) NMR analyses, we assessed the bonding of the APTMS to the silica surface and determined the best ratio of injected molecules to the surface area of the nanoparticle to obtain complete coverage. Then, we attached gold seeds to the silica surface, and we merged them by adding gold precursor through a slow injection, employing a syringe pump. In this way, we avoided self-nucleation of gold nanoparticles in the chemical environment, achieving uniform gold coverage. As a further development, by exploiting the variable thickness of the silica shell, the gold film could also be employed to build an optical microcavity around the QD (increasing the QD-gold film distance through a thicker silica shell). In general, silica shells around QDs can be used as a template to colloidally grow more sophisticated optical structures able to impart additional effects to tune the emitter properties.
Bibliography
(1) Carbone, L.; Nobile, C.; De Giorgi, M.; Sala, F. D.; Morello, G.; Pompa, P.; Hytch, M.; Snoeck, E.; Fiore, A.; Franchini, I. R.; Nadasan, M.; Silvestre, A. F.; Chiodo, L.; Kudera, S.; Cingolani, R.; Krahne, R.; Manna, L. Nano Lett. 2007, 7 (10), 2942–2950.
(2) Tessier, M. D.; Dupont, D.; De Nolf, K.; De Roo, J.; Hens, Z. Chem. Mater. 2015, 27 (13), 4893–4898.
(3) Fiorito, S.; Silvestri, M.; Cirignano, M.; Marini, A.; Di Stasio, F. ACS Appl. Nano Mater. 2024, 7 (4), 3724–3733
(4) Leardi, R. Analytica Chimica Acta 2009, 652 (1), 161–172.
(5) Ji, B.; Giovanelli, E.; Habert, B.; Spinicelli, P.; Nasilowski, M.; Xu, X.; Lequeux, N.; Hugonin, J.-P.; Marquier, F.; Greffet, J.-J.; Dubertret, B. Nature Nanotech 2015, 10 (2), 170–175
On the Influence of Input Variables on the Building Energy Modelling Process: A Sensitivity Analysis
No full textOn the impact of modified urban albedo on ambient temperature and heat related mortality
No full textUrban heat island and regional climate change raise the ambient temperature in cities and increase the levels of heat related mortality. Higher albedo values lower the ambient temperature and reduce the impact of excess urban heat on health. The present work reviews and analyses fourteen detailed studies investigating the impact of increased urban albedo on the ambient temperature and heat related mortality. It is found that the real magnitude of the afternoon temperature drop caused by the albedo increase is close to 0.09C per 0.1 rise of the albedo, and it is highly determined by the specific climatic, landscape and layout characteristic of cities. A statistically significant association of the temperature drop with the albedo increase, the greenery and street ratio in cities is found. It is observed that the levels of heat related mortality increase significantly as a function of the population size of the cities and the local poverty levels, Increased urban albedo is found to reduce heat related mortality between 0.1 and 4 deaths per day, corresponding to an average decrease of deaths close to 19.8% per degree of temperature drop, or 1.8% per 0.1 increase of the albedo. Mortality drop is found to be in statistically significant association with the initial heat related mortality levels, albedo increase and socioeconomic parameters like the local poverty levels. Accurate parametric functions to predict the magnitude of the temperature drop and heat mortality reduction are developed
On john maynard keynes's anti-semitism once again: A documentary note
Full text linkThis note presents new archival evidence about John Maynard Keynes' attitudes toward Jews. The relevant material is composed of two letters sent by Robert G. Wertheimer to Bertrand Russell and Richard F. Kahn along with their replies. Between 1963 and 1964, Wertheimer - An Austrian-born Jewish immigrant then professor of economics at Babson College - wrote to Russell and Kahn asking for their personal reminiscences concerning Keynes' anti-Semitic utterances. In their brief but still significant responses, both Russell and Kahn firmly denied any hint of anti-Semitism in Keynes, thereby providing significant first-hand testimonies from two of his closest acquaintances
L’attività brevettuale del settore CEAR-08/A. Analisi dei dati dell’ultimo decennio e riflessioni strategiche per il futuro
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