Search results for "rfa"
showing 10 items of 11106 documents
Protected but Accessible: Oxygen Activation by a Calixarene-Stabilized Undecagold Cluster
2013
DFT computations show that calixarenes stabilize subnanometer Au11 clusters allowing access of small molecules like O2 to reactive metal sites in the core. Maximum of three dioxygen molecules can bind to the cluster, and they are activated to a superoxo O2(-) state. This study predicts that gold clusters could act as viable oxidation catalysts at ambient conditions based on similar principles as the metal centers in enzymes.
Diastereomeric control of enantioselectivity: evidence for metal cluster catalysis
2014
Enantioselective hydrogenation of tiglic acid effected by diastereomers of the general formula [(μ-H)2Ru3(μ3-S)(CO)7(μ-P–P*)] (P–P* = chiral Walphos diphosphine ligand) strongly supports catalysis by intact Ru3 clusters. A catalytic mechanism involving Ru3 clusters has been established by DFT calculations. peerReviewed
Results on performance and ageing of solar modules based on Elkem Solar Silicon (ESS™) from installations at various locations
2014
Abstract The present study aims to present the current status of the results obtained using Elkem Solar Silicon (ESS™) as feedstock basis for solar cell and modules. It is shown that solar cells based on ESS™ are able to follow the development of the solar industry obtaining comparable efficiencies to standard polysilicon based cells. The characteristics of ESS™ based solar cells, having normally higher V oc and FF and lower I sc , seem to give clear advantages in the field for solar modules located at high irradiance areas. Results from several locations show enhanced electricity production of ESS™ based solar modules compared to polysilicon at increasing solar irradiance. This is explaine…
Melanin type and concentration determination using inverse model
2011
Abnormality of melanin production causes skin pigmentation disorders. Currently, assessment of treatment efficacy (under Physician's Global Assessment framework) only refers to visual conditions of skin surface and not the condition of the underlying skin layers and pigments. Albeit researches on models and simulations of light interaction with human skin have been reported, none has been specifically developed for pigmentation analysis of melanin types - eumelanin and pheomelanin. Therefore, our research objectives are to develop image analysis of skin pigmentation for classification and quantification of eumelanin and pheomelanin pigment types in human skin. In this research, the model is…
Measurement of the Fluctuations in the Number of Muons in Extensive Air Showers with the Pierre Auger Observatory
2021
The successful installation, commissioning, and operation of the Pierre Auger Observatory would not have been possible without the strong commitment and effort from the technical and administrative staff in Malargue. We are very grateful to the following agencies and organizations for financial support: Argentina-Comision Nacional de Energia Atomica, Agencia Nacional de Promocion Cientifica y Tecnologica (ANPCyT), Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Gobierno de la Provincia de Mendoza, Municipalidad de Malargue, NDM Holdings and Valle Las Lenas; in gratitude for their continuing cooperation over land access; Australia-the Australian Research Council; Brazil…
A Lightweight, User-Controlled System for the Home
2006
This paper explores how we designed, with input from some elderly persons, a multi-agent user-controlled network for the home. The system was designed to support the elderly in living longer at home with minimal support. We describe how our work attempts to tackle issues such as privacy, control of personal space, and enjoyment within the home. As the number of elderly individuals’ increases, a certain amount of information gathering or support may be required to assist the elderly in their homes. However, we strongly believe that we should preserve people’s privacy in their homes and ensure that any artifact we propose is seen as enjoyable, aesthetically pleasing and, most importantly, not…
Simulation of Fatigue Delamination Growth in Composites with Different Mode Mixtures
2007
A numerical model, obtained by implementing a cyclic damage model in the framework of an interface element, is here proposed to reproduce the crack growth in laminated composites subjected to cyclically repeated loads. This model, which differs from the few studies in the literature on the topic, applies not only to single fracture modes but also to mixed modes, and to constant or variable crack growth rates. The applied load (in terms of force or displacement) is assumed to oscillate between a minimum and a maximum constant value. The Paris curve can be reproduced with accuracy once some parameters in the numerical model are tuned with experiments. These parameters are preliminarily found…
Vers une assistance informatisée au diagnostic de la qualité ergonomique d'interfaces
2000
International audience; Notre objectif ici est d'encourager les concepteurs à s'intéresser aux usages de leur produit en prenant davantage en compte les facteurs humains dans la phase de test qui est souvent focalisée sur les aspects techniques. L'idée dans cette étude est donc de faciliter le recours aux utilisateurs comme source d'évaluation lors des tests de conception en apportant aux concepteurs un environnement logiciel de test pratique à mettre en œuvre pour faire évaluer leurs propres produits par des utilisateurs. Nous avons mené deux expériences de nature à explorer la faisabilité de ce projet.
Il calcestruzzo poroso per il miglioramento delle condizioni di stabilità dei pendii sede di falda idrica
2022
Reduction of pore water pressures is a useful strate-gy to improve the stability conditions of slopes. Deep draining trenches can be used for this scope. For the realisation of deep trenches, the usual con-ventional construction techniques are not adequate and the use of adjacent vertical panels, built by means of the methods well established for dia-phragm walls, is necessary. However, unbonded ma-terials (i.e. gravels) cannot be used, since the excava-tion of a panel adjacent to already built ones will cause instability. For this scope a bonded material such as the pervious concrete can be used. It must have high permeability, filtering capacity in order to prevent the internal erosion of…
La resistenza di interfaccia calcestruzzo poroso-terreni a grana fina per il consolidamento di pendii mediante trincee drenanti profonde
2022
Le trincee drenanti profonde rappresentano uno dei metodi più efficaci per la mitigazione del rischio da frana, in pendii con falda idrica. Esse sono realizzate mediante pannelli o pali secanti. Il riempimento è costituito di calcestruzzo poroso o materiale granulare. Se le trincee sono adeguatamente “innestate” nel terreno stabile e il materiale di riempimento ha sufficiente resistenza e rigidezza come il calcestruzzo poroso, si ha ulteriore in-cremento di resistenza a taglio per effetto shear keys, oltre a quello derivante dalla riduzione delle pressioni in-terstiziali. L’incremento di resistenza è dovuto sia alla resistenza all’interfaccia calcestruzzo–terreni sia a quella intrinseca del…