372 research outputs found
Behaviour of Li-ion on the surface of Ti3C2-T Mxene
No full textK. A. Papadopoulou, A. Chroneos and S.-R. G. Christopoulos, “Behaviour of Li-ion on the surface of Ti3C2-T Mxene”, World Sustainable Energy Days 2022, Wels, Austria, 5-8 April 202
An application of the coherent noise model for the prediction of aftershock magnitude time series
No full textRecently, the study of the coherent noise model has led to a simple (binary) prediction algorithm for the forthcoming earthquake magnitude in aftershock sequences. This algorithmis based on the concept of natural time and exploits the complexity exhibited by the coherent noise model. Here, using the relocated catalogue from Southern California Seismic Network for 1981 to June 2011, we evaluate the application of this algorithmfor the aftershocks of strong earthquakes of magnitudeM ≥ 6. The study is also extended by using the Global CentroidMoment Tensor Project catalogue to the case of the six strongest earthquakes in the Earth during the last almost forty years. The predictor time series exhibits the ubiquitous 1/f noise behavior. © 2017 Stavros-Richard G. Christopoulos and Nicholas V. Sarlis
Li–ion diffusion on the surface of Ti3C2-T (T=O, S, F, Cl, Br) MXene
No full textK. A. Papadopoulou, D. Parfitt, A. Chroneos and S.-R. G. Christopoulos, “Li–ion diffusion on the surface of Ti3C2-T (T=O, S, F, Cl, Br) MXene”, European Materials Research Society Spring 2022 meeting, 30 May-3 June 2022, onlin
An Introduction to Design Commons
No full textThe reasons for a dedicated edition on “design and commoning” are twofold. First, the recent surge of renewed interest in the social conditions of design remains atheoretical. A deeper theoretical and philosophical foundation will help problematize the link between commoning and design, and in doing so define the operative theories, concepts and frameworks that influence design thinking across a series of design contexts and conditions. And secondly, design has become more ubiquitous, expanding both its domain of influence and conditions of praxis. With this expansion, design touches a variety of contested areas. Designers are continuously challenged by conflicts and edge conditions, having to mitigate between both scales of conflict and the vested interests of individuals. In the global climate of population increase and the prevalent reduction of financial resources the question and theorization of shared capacities will remain part and parcel of future of design thinking. The four thematic clusters contained here exploit the theoretical and philosophical themes related to the large commoning “problematique,” providing designers better grounding in the networked context of the twenty-first century. The explicit theorization of design and the commons will explore the implicit relations through each of the collected contributions to show how this philosophical construct can be explicated in the context of network collectives and transdisciplinary approaches that currently inform design practices.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Theory, Territories & Transition
Pings and Hups
No full textEtymologically unattested yet artistically long praised, there is a profound relation between life and light; next to both, the almost self-evident (and scientifically undisputed) relation between light and flow, lux and flux. Would it be correct then to understand life as an issue of perception and manipulation of flows? Surprisingly, this is a question that can only be answered by addressing death. As any lensmaker would claim (and philosophy has always had an affinity with this profession), perception is not a synthesis but an ascesis: it does not connect, it disconnects; or, better said, in order to connect, it needs to disconnect. However, following the radical empiricist dictum, one should never speak of perception alone; ever since William James, perception equals action. In other words, perception is not something that happens to us, it is something we do.5 Strange as it may seem therefore, to live one needs to practice death. This book will examine how styling life means styling death and how architecture (in the broadest possible sense) is involved in this continuous process of stylisation. To do so, architecture and perception, duration and individuation, will all converge in practising how one can die without dying in order to enunciate a life.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Theory, Territories & Transition
Un nouveau manuscrit grec illustré du Physiologus : au sujet d'une récente étude sur ce texte
No full textThe author draws the attention on a Physiologus' manuscript actually in the Ivan Dujčev Center, Sofia, which has not been taken into account in a recent study.REB 58 2000 France p. 277-281
St. Lazaris, Un nouveau manuscrit grec illustré du Physiologus : au sujet d'une étude récente sur ce texte. — L'auteur signale la présence d'un manuscrit du Physiologus conservé au Centre Ivan Dujčev à Sofia et qui n'a pas été pris en considération dans une récente étude de ce texte.Lazaris Stavros. Un nouveau manuscrit grec illustré du Physiologus : au sujet d'une récente étude sur ce texte. In: Revue des études byzantines, tome 58, 2000. pp. 279-281
The chemistry of nonasilane
No full textObwohl Hydrosilan-Oligomere SinHm (n > 3) mit linearen, verzweigten oder zykli-schen Strukturen schon seit über 40 Jahren bekannt sind, verblieb diese Chemie seither dennoch nahezu unerforscht, was hauptsächlich auf ihre limitierten Zu-gänglichkeit und ihre ungünstigen Eigenschaften zurückzuführen ist. Seit neu-estem wurde herausgefunden, dass Cyclopolysilane SinH2n (n = 5,6) als Grund-stoffe für die Flüssigabscheidung von Siliziumschichten verwendet werden kön-nen, was eine beträchtliche Reduktion an Herstellungskosten im Vergleich zur üblichen Gasphasenabscheidung (CVD) bedeutet. Diese Grundstoffe bringen jedoch auch ungünstige Eigenschaften wie Leichtflüchtigkeit und Pyrophorizität mit sich. Ziel dieser Arbeit war es daher aus diesem Grund, mögliche Synthese-routen zu Nonasilan (Si9H18) zu untersuchen, welches überlegene Eigenschaf-ten bezüglich der Flüssigphasenabscheidung aufweisen könnte.Although hydrosilane oligomers SinHm (n > 3) with linear, branched or cyclic structures are known for more than 40 years, their chemistry still remained nearly unexplored since then, which is mainly due to their limited accessibility and their disadvantageous properties. Just recently it has been found that cyclopolysilanes SinH2n (n = 5,6) and neopentasilane (NPS) can be used as precursors for the so-lution-based deposition of silicon layers allowing significant reduction of pro-cessing costs in photovoltaic applications as compared to standard vacuum-based (CVD) approaches. However, these precursors entail some unfavourable properties like their unsuitable volatility and their undesirable pyrophoric charac-ter on contact with air. Thus, this work aims to investigate a possible synthetic route to nonasilane (Si9H18) and its various functionalized variations, which could display improved characteristics for liquid phase silicon deposition (LPD).vorgelegt von BSc. Viktor-Stavros ChristopoulosMasterarbeit Karl-Franzens-Universität Graz 2017 747
Hydrogen and nitrogen codoping of anatase TiO<sub>2</sub> for efficiency enhancement in organic solar cells
Get PDFTiO2 has high chemical stability, strong catalytic activity and is an electron transport material in organic solar cells. However, the presence of trap states near the band edges of TiO2 arising from defects at grain boundaries significantly affects the efficiency of organic solar cells. To become an efficient electron transport material for organic photovoltaics and related devices, such as perovskite solar cells and photocatalytic devices, it is important to tailor its band edges via doping. Nitrogen p-type doping has attracted considerable attention in enhancing the photocatalytic efficiency of TiO2 under visible light irradiation while hydrogen n-type doping increases its electron conductivity. DFT calculations in TiO2 provide evidence that nitrogen and hydrogen can be incorporated in interstitial sites and possibly form NiHi, NiHO and NTiHi defects. The experimental results indicate that NiHi defects are most likely formed and these defects do not introduce deep level states. Furthermore, we show that the efficiency of P3HT:IC60BA-based organic photovoltaic devices is enhanced when using hydrogen-doping and nitrogen/hydrogen codoping of TiO2, both boosting the material n-type conductivity, with maximum power conversion efficiency reaching values of 6.51% and 6.58%, respectively, which are much higher than those of the cells with the as-deposited (4.87%) and nitrogen-doped TiO2 (4.46%).</p
Topics in minimax shrinkage estimation
No full textThe dissertation considers three different topics which pertain to minimax shrinkage estimation:
1) Minimax estimation of a mean vector with variable selection for classes of spherically symmetric distributions: The results of Zhou and Hwang [31] and Maruyama [22] are extended from the normal case with known scale, to scale mixtures of normals and more generally to spherically symmetric distributions with a residual vector. Slight extensions to the class of estimators to which the results pertain are also given.
2) Minimax shrinkage estimators of a location vector under concave loss: In particular it is shown for a wide class of concave loss functions, James-Stein and Baranchik-type estimators which dominate the usual" estimator for quadratic loss also dominate for these concave losses. The distributions studied include multivariate normal distributions with covariance equal to a known multiple of the identity, normal distributions with an unknown scale times the identity, and general scale mixtures of multivariate normal distributions with an unknown scale.
3) Combining unbiased and possibly biased correlated estimators of a mean vector under general quadratic loss: The general approach is to use a shrinkage-type estimator which shrinks an unbiased estimator toward a biased estimator. Conditions under which the combined estimator dominates the original unbiased estimator are given. Models studied include normal models with a known covariance structure, scale mixtures of normals, and more generally elliptically symmetric models with a known covariance structure. Elliptically symmetric models with a covariance structure known up to a multiple are also considered.Ph.D.Includes bibliographical referencesby Stavros Zinono
A Diagrammatic Cartography of Discourses on Architectures of Life and/or Death
No full textThe built environment exerts an essential effect on life. Over the past decades, it has been greatly reconceptualised through various posthuman, ecosystemic, new materialist, material-discursive approaches, which explored the socio-spatial, technological, cognitive, relational, and affective relations that material arrangements, such as architectural ones, shape. As technē, architecture is intricately intertwined not only with processes of easing and facilitating (human) life, but also the management of dynamic processes involving both living and non-living matters. In view of the latter, architecture is ‘life by means other than life’ (Stiegler), shaping living matters by means of non-living matters. The chapter respectively surveys several streams of recent theoretical discourse that developed from Deleuze and Guattari’s as well as Foucault’s thoroughgoing reframing of the agency of matter on life-constituting processes. In the aim of reconsidering and repositioning architecture as a posthuman technique of existence, this cartography charts – with the help of a central navigational diagram – these co-evolving discursive streams in their differing topical-conceptual starting points, and their various converging and bifurcating lines of thinking, in the aim to elaborate on the novel conceptions they have helped distil in the pursuit of a fuller understanding of those material-discursive practices within the relational ecologies of architecture.Accepted Author ManuscriptSituated Architectur
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