Search results for " technology and society"
showing 10 items of 38 documents
Insights into Intrinsic Defects and the Incorporation of Na and K in the Cu2ZnSnSe4 Thin-Film Solar Cell Material from Hybrid-Functional Calculations
2016
We have performed density functional theory calculations using the HSE06 hybrid functional to investigate the energetics, atomic, and electronic structure of intrinsic defects as well as Na and K impurities in the kesterite structure of the Cu2ZnSnSe4 (CZTSe) solar cell material. We found that both Na and K atoms prefer to be incorporated into this material as substitutional defects in the Cu sublattice. At this site highly stable (Na–Na), (K–K), and (Na–K) dumbbells can form. While Na interstitial defects are stable in CZTSe, the formation of K interstitial defects is unlikely. In general, the calculated formation energies for Na-related defects are always lower compared to their K-related…
BIAM: a new bio-inspired analysis methodology for digital ecosystems based on a scale-free architecture
2017
Today we live in a world of digital objects and digital technology; industry and humanities as well as technologies are truly in the midst of a digital environment driven by ICT and cyber informatics. A digital ecosystem can be defined as a digital environment populated by interacting and competing digital species. Digital species have autonomous, proactive and adaptive behaviors, regulated by peer-to-peer interactions without central control point. An interconnecting architecture with few highly connected nodes (hubs) and many low connected nodes has a scale- free architecture. A new bio-inspired analysis methodology (BIAM) environment, an investigation strategy for information flow, fault…
Direct gravimetric sensing of GBL by a molecular recognition process in organic cage compounds.
2013
Organic cages were identified as highly potent affinity materials for the tracing of γ-butyrolactone. The selectivity over ethanol and water is based on the interior functional groups which allow preferential hydrogen bonding to the target analyte.
MINISAT-01: Hybrid satellite for science and technology
2003
Abstract The MINISAT-01 is a good example of a small hybrid space mission for science and technology. The MINISAT-01 main goal was to prove the Spanish industrial capability to develop a space mission including flight hardware, ground segment support, launch and operations. MINISAT-01 science was addressed to perform astronomical observations and microgravity experiments. The Payload has also a hybrid character. It is a combination of a previously flown experiment on fluid mechanics in microgravity (CPLM), a fully developed astronomical far-ultraviolet spectroscope (EURD) and a demonstrator of technology for a gamma-ray imagers (LEGRI). A small experiment to deploy systems in space was also…
Demixing time and temperature influence on porosity and interconnection of PLLA scaffolds prepared via TIPS
2009
Scaffolds suitable for tissue engineering applications were prepared by Thermally Induced Phase Separation (TIPS) starting from a ternary solution PLLA/ dioxane/water. The experimental protocol consisted of three consecutive steps, a first quench from the homogeneous solution to an appropriate demixing temperature (within the binodal region), a liquid-liquid demixing stage for a given time and a final quench from the demixing temperature to a low temperature (within the spinodal region). A large variety of morphologies, in terms of average pore size and interconnection were obtained upon modifying the demixing time and temperature, owing to the interplay of nucleation and growth processes d…
Comparison of thermal‐ and photo‐polymerization of lauryl methacrylate monolithic columns for CEC
2009
Lauryl methacrylate-based (LMA) monolithic columns for CEC, prepared using either thermal initiation or by UV-irradiation in the presence of AIBN have been compared. Thermal polymerization was carried out at 70 degrees C for 20 h. For UV initiation, the effects of the time exposure to UV light and irradiation energy were investigated. For each initiation process, the influence of composition of porogenic solvent (1,4-butanediol/1-propanol ratio) on the physical and electrochromatographic properties of the resulting monoliths was also evaluated. Photochemically lauryl methacrylate stationary phases initiated showed higher permeabilities and better efficiencies than those prepared by thermal …
Atomically Precise Alkynyl-Protected Metal Nanoclusters as a Model Catalyst: Observation of Promoting Effect of Surface Ligands on Catalysis by Metal…
2016
Metal nanoclusters whose surface ligands are removable while keeping their metal framework structures intact are an ideal system for investigating the influence of surface ligands on catalysis of metal nanoparticles. We report in this work an intermetallic nanocluster containing 62 metal atoms, Au34Ag28(PhC≡C)34, and its use as a model catalyst to explore the importance of surface ligands in promoting catalysis. As revealed by single-crystal diffraction, the 62 metal atoms in the cluster are arranged as a four-concentric-shell Ag@Au17@Ag27@Au17 structure. All phenylalkynyl (PA) ligands are linearly coordinated to the surface Au atoms with staple "PhC≡C-Au-C≡CPh" motif. Compared with reporte…
Enhanced chemosensing of ammonia based on the novel molecular semiconductor-doped insulator (MSDI) heterojunctions
2011
Abstract A series of new molecular semiconductor-doped insulator (MSDI) heterojunctions as conductimetric transducers to NH3 sensing were fabricated based on a novel semiconducting molecular material, an amphiphilic tris(phthalocyaninato) rare earth triple-decker complex, Eu2[Pc(15C5)4]2[Pc(OC10H21)8], quasi-Langmuir–Shafer (QLS) film, as a top-layer, and vacuum-deposited and cast film of CuPc as well as copper tetra-tert-butyl phthalocyanine (CuTTBPc) QLS film as a sub-layer, named as MSDIs 1, 2 and 3, respectively. MSDIs 1–3 and respective sub-layers prepared from three different methods were characterized by X-ray diffraction, electronic absorption spectra and current–voltage (I–V) measu…
Nanotechnology for Photovoltaic Cells and Energy Efficiency
2015
Abstract. The intent of this paper is to connect science and technology in order to demonstrate how, in the field of on photovoltaic technologies, thin film solar cells have been the focus of many research facilities in recent years that are working to decrease manufacturing costs and increase cell efficiency. New research suggests that it might be possible to add a nanoscopic relief pattern to the surface of solar cells that makes them non-reflective significantly boosting efficiency and at the same time making them highly non-stick and self-cleaning. The paper presents the challenges and approaches to engineer the active layer of the cell, in order to obtain cells made up of components as…
A heuristic fuzzy algorithm for assessing and managing tourism sustainability
2019
“Smartness” and “sustainability” are gaining growing attention from both practitioners and policy makers. “Smartness” and “sustainability” assessments are of crucial importance for directing, in a systemic perspective, the decision-making process toward sustainability and smart growth objectives. Sustainability assessment is a major challenge due to the multidisciplinary aspects involved that make the evaluation process complex and hinder the effectiveness of available monitoring tools. To achieve the assessment objective, we introduce an enhanced fuzzy logic-based framework for handling the inherent uncertainty and vagueness of the involved variables: we apply our approach to Italy, and we…