Search results for "Technology"
showing 10 items of 30343 documents
Oxidation-responsive and "clickable" poly(ethylene glycol) via copolymerization of 2-(methylthio)ethyl glycidyl ether
2016
Poly(ethylene glycol) (PEG) is a widely used biocompatible polymer. We describe a novel epoxide monomer with methyl-thioether moiety, 2-(methylthio)ethyl glycidyl ether (MTEGE), which enables the synthesis of well-defined thioether-functional poly(ethylene glycol). Random and block mPEG-b-PMTEGE copolymers (Mw/Mn = 1.05-1.17) were obtained via anionic ring opening polymerization (AROP) with molecular weights ranging from 5 600 to 12 000 g·mol-1. The statistical copolymerization of MTEGE with ethylene oxide results in a random microstructure (rEO = 0.92 ± 0.02 and rMTEG E = 1.06 ± 0.02), which was confirmed by in situ 1H NMR kinetic studies. The random copolymers are thermorespon…
The new face of university–business cooperation in Finland
2016
This paper analyses the development of university-business cooperation (UBC) in Finland in the context of the University Reform Act of 2009, drawing on the experience of four universities: Aalto University, University of Jyvaskyla, University of Turku, and Lappeenranta University of Technology. Six UBC dimensions are examined: institutional context, stakeholders, motivations, facilitators/inhibitors, benefits, and drawbacks. We find that UBC, while a relatively recent process, is growing fast in dynamic local innovation and entrepreneurship ecosystems. The University Act of 2009 had an uneven effect on the six UBC dimensions, with the most visible impact being manifested on motivations. Aal…
Overview of Power Electronic Switches: A Summary of the Past, State-of-the-Art and Illumination of the Future.
2020
As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progr…
A Study on the Assessment of Introductory Computational Thinking via Scratch Programming in Primary Schools
2018
Computational thinking (CT), a transversal intellectual foundation integral to computer science, is making its way into compulsory comprehensive education worldwide. Students are expected to attain skills and knowledge in such interdisciplinary CT principles as Algorithmic thinking, Data representation, and Debugging. Problem-solving by designing and manipulating interactive media with Scratch, a graphical programming tool, is popular especially at the primary school level. However, there has been confusion regarding how introductory CT can be operationalized for educational practice. Teachers and students need research-based knowledge for setting appropriate learning goals in addition to i…
Measuring and Supporting Pre-Service Teachers’ Self-Efficacy Towards Computers, Teaching, and Technology Integration
2016
This paper reports on two studies designed to examine pre-service teachers’ self-efficacy beliefs. Study I investigated the measurement properties of a self-efficacy beliefs questionnaire comprising scales for computer self-efficacy, teacher self-efficacy, and self-efficacy towards technology integration. In Study I, 200 pre-service teachers completed the self-efficacy questionnaire. Confirmatory factor analyses resulted in a modified measurement model consisting of the three hypothesized self-efficacy scales. Study II reports on an intervention to clarify the effects of digital video composition experiences on these same three self-efficacy variables. Participants were 22 pre-service teach…
Timber framed with masonry infill: a historical anti-seismic device. The Portuguese Pombaline gaiola.
2017
La ricostruzione postsismica e la prevenzione sismica sono stati da sempre un fondamento costruttivo.Questo studio analizza la tipologia costruttiva della gaiola pombalina, un sitema costruttivo e strutturale molto diffuso in Portogallo ma non solo, adottato a Lisbona a seguito del terremoto del 1755. Si analizzano i materiali e le tecniche costruttive, gli elementi utili al rinforzo e consolidamento della struttura muraria, ampiamente diffuso in area mediterranea a partire dal XVIII secolo.Questo sistema costruttivo può e deve anche oggi essere considerato un utile presidio antisismico da riconoscere e preservare da interventi incolti, se non addirittura da incongrue demolizioni. Post-seis…
Progress in HAXPES performance combining full-field k-imaging with time-of-flight recording
2019
Journal of synchrotron radiation 26(6), 1996-2012 (2019). doi:10.1107/S1600577519012773
Unlocking mixed oxides with unprecedented stoichiometries from heterometallic metalorganic frameworks for the catalytic hydrogenation of CO 2
2021
[EN] Their complex surface chemistry and high oxygen lattice mobilities place mixed-metal oxides among the most important families of materials. Modulation of stoichiometry in mixed-metal oxides has been shown to be a very powerful tool for tuning optical and catalytic properties. However, accessing different stoichiometries is not always synthetically possible. Here, we show that the thermal decomposition of the recently reported metal-organic framework MUV-101(Fe, Ti) results in the formation of carbon-supported titanomaghemite nanoparticles with an unprecedented Fe/Ti ratio close to 2, not achievable by soft-chemistry routes. The resulting titanomaghemite phase displays outstanding catal…
Calcium mediated polyelectrolyte adsorption on like-charged surfaces.
2011
International audience; Monte Carlo simulations within the primitive model of calcium-mediated adsorption of linear and comb polyelectrolytes onto like-charged surfaces are described, focusing on the effect of calcium and polyion concentrations as well as on the ion pairing between polymers and calcium ions. We use a combination of Monte Carlo simulations and experimental data from titration and calcium binding to quantify the ion pairing. The polymer adsorption is shown to occur as a result of surface overcharging by Ca2+ and ion pairing between charged monomers and Ca2+. In agreement with experimental observations, the simulations predict that the polymer adsorption isotherm goes through …
Voltammetric Detection of Lead(II) Using Amide-Cyclam- Functionalized Silica-Modified Carbon Paste Electrodes
2009
2-(4,8,11-Triscarbamoylmethyl-1,4,8,11-tetraazacyclotetradec-1-yl)acetamide (TETAM) derivatives bearing 1, 2, or 4 silylated arms have been synthesized and grafted to the surface of silica gel and ordered mesoporous silica samples. The resulting organic-inorganic hybrids have been incorporated into carbon paste electrodes and applied to the preconcentration electroanalysis of Pb(II). The attractive recognition properties of these cyclam derivatives functionalized with amide pendent groups toward Pb(II) species and the highly porous structure of the adsorbents can be exploited for the selective and sensitive detection of the target analyte. Various parameters affecting the preconcentration a…