Search results for "Kite"

TIO2 brookite: Properties, synthesis and applications

2017

Brookite is one of the less studied polymorphic phases of titanium dioxide. Indeed, synthetic procedures affording brookite as a pure phase were not straightforward and have been only recently optimized. For this reason, brookite has received particular attention in the last years, especially as a promising photocatalytic material for environmental remediation and for the synthesis of valuable organic products. The present chapter will review the main synthetic methods reported in literature to produce brookite as a pure phase or mixed with rutile and/or anatase. Morphological, structural and electronic properties both of pure or variously modified brookite will be presented. The particular…

STEAM Practices to Explore Ancient Architectures Using Augmented Reality and 3D Printing with GeoGebra

2021

Abstract In this study, we develop mathematical educational practices for students to explore ancient buildings using GeoGebra, Augmented Reality and 3D printing. It is an interdisciplinary approach, intertwining history, culture, mathematics, and engineering. For example, the 3D modelling of Cheomseongdae in Korea and the Temple of Dendera in Egypt can enable students to practice a multimodal set of traditional and innovative learning approaches. Students might use their mathematical knowledge to reflect on architectural and cultural history in a modeling task.

Enterprise JavaBeans -komponenttimalli ja sen vaikutus ohjelmistonkehitykseen

2001

EJB:n eri käyttötapojen tehokkuus tiedonsiirrossa tietokantaan käyttäen OC4J palvelinta

2002

Management Structure Based Government Enterprise Architecture Framework Adaption in Situ

2017

Part 1: Regular Papers; International audience; The fragmentation of the public sector makes it difficult to manage strategically and architecturally as a whole. Enterprise Architecture (EA) is considered as an improvement to that. Architectural modeling and visualization of the general management strategy plans along with parallel database development in a local government forms the primary data in the longitudinal case study using Action Design Research Method. To find a proper organizational fit for the EA framework in public sector, we reflect on how the current state architectural descriptions got organized in situ in a deep corporate hierarchy, and what were the emerging management ne…

Business architecture development at public administration - Insights from government EA method engineering project in Finland

2008

Governments worldwide are concerned for efficient production of services to customers. To improve quality of services and to make service production more efficient, information and communication technology (ICT) is largely exploited in public administration (PA). Succeeding in this exploitation calls for large-scale planning which embraces issues from strategic to technological level. In this planning the notion of enterprise architecture (EA) is commonly applied. One of the sub-architectures of EA is business architecture (BA). BA planning is challenging in PA due to a large number of stakeholders, a wide set of customers, and solid and hierarchical structures of organizations. To support …

Pressure Impact on the Stability and Distortion of the Crystal Structure of CeScO3

2017

[EN] The effects of high pressure on the crystal structure of orthorhombic (Pnma) perovskite-type cerium scandate were studied in situ under high pressure by means of synchrotron X-ray powder diffraction, using a diamond-anvil cell. We found that the perovskite-type crystal structure remains stable up to 40 GPa, the highest pressure reached in the experiments. The evolution of unit-cell parameters with pressure indicated an anisotropic compression. The room-temperature pressure¿volume equation of state (EOS) obtained from the experiments indicated the EOS parameters V0 = 262.5(3) Å3 , B0 = 165(7) GPa, and B0¿ = 6.3(5). From the evolution of microscopic structural parameters like bond distan…

Perovskite Solar Cells: Stable under Space Conditions

2020

Metal halide perovskite solar cells (PSCs) are of interest for high altitude and space applications due to their lightweight and versatile form factor. However, their resilience toward the particle spectrum encountered in space is still of concern. For space cells, the effect of these particles is condensed into an equivalent 1 MeV electron fluence. The effect of high doses of 1 MeV e-beam radiation up to an accumulated fluence to 10^16 e-cm-2 on methylammonium lead iodide perovskite thin films and solar cells is probed. By using substrate and encapsulation materials that are stable under the high energy e-beam radiation, its net effect on the perovskite film and solar cells can be studied.…

Quantum mechanics-molecular dynamics approach to the interpretation of x-ray absorption spectra.

2009

The quantum mechanics-molecular dynamics approach to the simulation of configuration-averaged EXAFS spectra is proposed, and its application is discussed for the example of the Ti K-edge EXAFS spectrum in cubic perovskite SrTiO(3). Proper use of ab initio quantum mechanics allows a number of empirical parameters, used in the molecular dynamics simulation, to be reduced, whereas the molecular dynamics allows us to account for temperature effects. All together, the approach provides a way of accounting for static and dynamic disorder in EXAFS signals from the coordination shells above the first one, where many-atom (multiple-scattering) effects are often important.

Toward tailorable surfaces: a combined theoretical and experimental study of lanthanum niobate layered perovskites.

2014

A comprehensive theoretical investigation of the MLaNb2O7 (M = H, Li, Na, K, Rb, and Cs) series of ion-exchangeable layered perovskite is presented. These perovskites are in particular interesting in view of their potential applications as inorganic supports for the design of new hybrid inorganic-organic proton conductors. In particular, their structural and electronic properties have been investigated by periodic calculations in the framework of Density Functional Theory, using different exchange-correlation functionals. A general very good agreement with the available experimental (XRD, NPD, and EXAFS) data has been found. The structure of the protonated HLaNb2O7 form has also been furthe…