Herramientas para generar sobre Web ejercicios de ajedrez interactivos para principiantes

Este proyecto consiste en la realización de una herramienta para generar ejercicios de ajedrez para principiantes. Con dicha herramienta se permiten crear varios tipos de ejercicios con la finalidad de que un alumno con un nivel básico de conocimientos ajedrecísticos pueda practicar lo aprendido. El resultado final de estos ejercicios se visualiza en un Applet lo que permite su integración en una página Web. A tal efecto y para facilitar el aprendizaje se ha creado un sitio Web, donde se explican las nociones básicas del ajedrez en la que se incluyen ejemplos de ejercicios tipos generados con la herramienta desarrollada. [ABSTRACT] This project consists on the realization of a tool to generate exercises of ches s for beginners . This tool allows creating several types of exercis es with the goal that a s tudent with a basic level of chess knowledge can practice his skill. The final result of these exercises is visualized in an Applet that allows it integration on the Web. To facilitate the learning, a Web s ite has been created. This Web site includes basic knowledge of chess with examples of exercises types generated with the developed tool

Role of dendritic cell subsets in hyperlipidemia and atherosclerosis

Dendritic cells (DCs) are essential to ensuring adequate immune response, but are also involved in several chronic conditions, such as atherosclerosis. This dissertation examines how DCs influence atherosclerosis. It found that certain DCs involved in cellular immune response have very little influence on disease progression. This study also demonstrated that elevated cholesterol levels are an important indicator for atherosclerosis and can impair DC functioning and the immune system. Finally, it was discovered that deactivating DC quaking slows disease progression. This finding makes quaking an interesting target protein for treating atherosclerosis

Op zoek naar de kern van leeszwakte : analyse van het leesproces van dyslectische kinderen

In search of the core of dyslexia. Analysis of the reading process of dyslectic children This anicle gives an overall picture of research into reading processes for dyslectic children who in other respects develop normally. The research was aimed at finding a defect in one of the basic functions of the normal reading process. By means of a block diagram of mainly visual word recognition, an attempt is made to analyse the core of dyslexia. The weak link is presumed to be in the translation from an internat visual word image to an internal speech image of the same word. The visual analysis itself, as well as the speech ability, is supposed completely norma

Co-designing innovative cropping systems through long-term on-farm experiments (DiverIMPACTS Practice Abstract)

This participatory research design that mixes scientific knowledge with actors’ points of view allows for these groups to deal with a complex systemic transition where there is often a shared long-term vision but the concrete form it will take remains largely unknown. It avoids the reproduction of errors, reduces the social, technical and financial risks inherent to change and combines the acquisition of social, technical and scientific knowledge into a coherent corpus while fostering the adoption and propagation of innovation

Détermination et calcul premiers principes, par la méthode PAW/GIPAW, de paramètres RMN de fluorures inorganiques

Cette thèse porte sur la détermination et la modélisation, par la méthode PAW/GIPAW (Gauge Including Projector Augmented Waves), de paramètres RMN de fluorures inorganiques. Dans la première partie, une corrélation entre valeurs expérimentales de déplacements chimiques isotropes (diso) de 19F et de constantes d'écran isotropes (iso) de F calculées de fluorures binaires, dont les attributions sont triviales, est établie. Elle permet de prédire les spectres RMN de 19F avec une bonne précision. Les paramètres quadripolaires de ces fluorures sont aussi déterminés et calculés. Dans la seconde partie, la linéarité entre valeurs expérimentales de diso de 19F et valeurs calculées de iso de 19F permet une attribution non ambigüe des raies RMN de 19F de NbF5 et TaF5. Par contre, pour trois des quatre composés MF4 étudiés (b-ZrF4, HfF4, CeF4, ThF4), caractérisés par des gammes de valeurs de diso de 19F plus petites, les corrélations médiocres entre valeurs de diso et de siso de 19F ne le permettent pas. Enfin, NaAsF6 et KPF6 qui présentent des valeurs élevées de couplage 1J 19F-X et des transitions de phase à des températures proches de l'ambiante sont étudiés par DTA ou DSC et diffraction des rayons X sur poudre et RMN du solide multinucléaire à température variable. Les structures de a- et b-NaAsF6 sont déterminées. KPF6 adopte une structure de haute symétrie désordonnée à température ambiante mais les tentatives de détermination des positions atomiques des deux premières phases basse température sont restées vaines. Ce travail souligne les potentialités et quelques limites de cette méthode ainsi que l'attention qui doit être prêtée aux effets des optimisations.This thesis focuses on the determination and the modeling, by the PAW/GIPAW (Gauge Including Projector Augmented Waves) method, of NMR parameters in inorganic fluorides. In the first part, a correlation between experimental 19F isotropic chemical shift (diso) and calculated 19F isotropic shieldings (siso) of binary fluorides with obvious assignments is established that allows to predict 19F NMR spectra with a good accuracy. The quadrupolar parameters of these fluorides are also determined and calculated. In the second part, a complete and unambiguous assignment of the 19F NMR lines of NbF5 and TaF5 is obtained, ensured by the linearity between experimental 19F diso values and calculated 19F siso values. On the other hand, for the studied MF4 (b-ZrF4, HfF4, CeF4, ThF4) compounds, characterized by smaller 19F diso ranges, except for ThF4, the poor correlations between experimental 19F diso and calculated 19F siso values prevent us to propose an assignment of the 19F NMR lines. In the last part, NaAsF6 and KPF6, exhibiting large 19F-X 1J-coupling and phase transitions at temperatures close to room temperature (RT) are investigated by DTA or DSC and variable temperature X-ray powder diffraction and multinuclear solid-state NMR. The structures of a- and b-NaAsF6 are determined. KPF6 adopts a disordered high symmetry structure at RT. Unfortunately, attempts to determine the atomic positions of the two first low temperature phases remain unsuccessful. This work highlights the potentialities and some limitations of this method as well as the care that must be taken when dealing with optimized structures.LE MANS-BU Sciences (721812109) / SudocSudocFranceF

Exploiting Cationic Vacancies for Increased Energy Densities in Dual-Ion Batteries

© 2019 Elsevier B.V. Dual-ion Li–Mg batteries offer a potential route to cells that combine desirable properties of both single-ion species. To maximize the energy density of a dual-ion battery, we propose a strategy for achieving simultaneous intercalation of both ionic species, by chemically modifying the intercalation host material to produce a second, complementary, class of insertion sites. We show that donor-doping of anatase TiO2 to form large numbers of cationic vacancies allows the complementary insertion of Li+ and Mg2+ in a dual-ion cell with a net increase in cell energy density, due to a combination of an increased reversible capacity, an increased operating voltage, and a reduced polarization. By tuning the lithium concentration in the electrolyte, we achieve full utilization of the Ti4+/Ti3+ redox couple with excellent cyclability and rate capability. We conclude that native interstitial sites preferentially accommodate Li+ ions, while Mg2+ ions occupy single-vacancy sites. We also predict a narrow range of electrochemical conditions where adjacent vacancy pairs preferentially accommodate one ion of each species, i.e., a [LiTi ​+ ​MgTi] configuration. These results demonstrate the implementation of additional host sites such as cationic sites as an effective approach to increase the energy density in dual-ion batteries

Correlated Anion Disorder in Heteroanionic Cubic TiOF 2

Resolving anion configurations in heteroanionic materials is crucial for understanding and controlling their properties. For anion-disordered oxyfluorides, conventional Bragg diffraction cannot fully resolve the anionic structure, necessitating alternative structure determination methods. We have investigated the anionic structure of anion-disordered cubic (ReO3-type) TiOF2 using X-ray pair distribution function (PDF), 19F MAS NMR analysis, density functional theory (DFT), cluster expansion modeling, and genetic-algorithm structure prediction. Our computational data predict short-range anion ordering in TiOF2, characterized by predominant cis-[O2F4] titanium coordination, resulting in correlated anion disorder at longer ranges. To validate our predictions, we generated partially disordered supercells using genetic-algorithm structure prediction and computed simulated X-ray PDF data and 19F MAS NMR spectra, which we compared directly to experimental data. To construct our simulated 19F NMR spectra, we derived new transformation functions for mapping calculated magnetic shieldings to predicted magnetic chemical shifts in titanium (oxy)­fluorides, obtained by fitting DFT-calculated magnetic shieldings to previously published experimental chemical shift data for TiF4. We find good agreement between our simulated and experimental data, which supports our computationally predicted structural model and demonstrates the effectiveness of complementary experimental and computational techniques in resolving anionic structure in anion-disordered oxyfluorides. From additional DFT calculations, we predict that increasing anion disorder makes lithium intercalation more favorable by, on average, up to 2 eV, highlighting the significant effect of variations in short-range order on the intercalation properties of anion-disordered materials

Controlled hydroxy-Fluorination Reaction of Anatase to Promote Mg²⁺ Mobility in Rechargeable Magnesium Batteries

International audienceIn anatase TiO2, substituting oxide anions with singly charged (F,OH) anions allows the controlled formation of cation vacancies, which act as reversible intercalation sites for Mg2+. We show that ion-transport (diffusion coefficients) and intercalation (reversible capacity) properties are controlled by two critical parameters: the vacancy concentration and the local anionic environment. Our results emphasise the complexity of this behaviour, and highlight the potential benefits of chemically controlling cationic-defects in electrode materials for rechargeable multivalent-ion batteries