Neutral atoms in ionic lattices: Excited states of KCl:Ag(0)

The optical-absorption spectrum of a cationic Ag0 atom in a KCl crystal has been studied theoretically by means of a series of cluster models of increasing size. Excitation energies have been determined by means of a multiconfigurational self-consistent field procedure followed by a second-order perturbation correlation treatment. Moreover results obtained within the density-functional framework are also reported. The calculations confirm the assignment of bands I and IV to transitions of the Ag-5s electron into delocalized states with mainly K-4s,4p character. Bands II and III have been assigned to internal transitions on the Ag atom, which correspond to the atomic Ag-4d to Ag-5s transition. We also determine the lowest charge transfer (CT) excitation energy and confirm the assignment of band VI to such a transition. The study of the variation of the CT excitation energy with the Ag-Cl distance R gives additional support to a large displacement of the Cl ions due to the presence of the Ag0 impurity. Moreover, from the present results, it is predicted that on passing to NaCl:Ag0 the CT onset would be out of the optical range while the 5s-5p transition would undergo a redshift of 0.3 eV. These conclusions, which underline the different character of involved orbitals, are consistent with experimental findings. The existence of a CT transition in the optical range for an atom inside an ionic host is explained by a simple model, which also accounts for the differences with the more common 3d systems. The present study sheds also some light on the R dependence of the s2-sp transitions due to s2 ions like Tl+.

Managing Scholarly Communication in the Web 2.0 Environment: The Role of University Libraries

Scholarly communication over the past 10 to 15 years has gained a tremendous momentum with the advent of Internet and the World Wide Web. The web has transformed the ways by which people search, find, use and communicate information. Innovations in web technology since 2005 have brought out an array of new services and facilities and an enhanced version of the web named Web 2.0. Web 2.0 facilitates a collaborative environment in which the information users can interact with the information. Web 2.0 enables its users to create, annotate, review, share re-use and represent the information in new ways thereby optimizing the information dissemination

Web 2.0 Technologies for Education

Page 1. Web 2.0 Technologies for Education G. Santhosh Kumar Dept. Of Computer Science Cochin University Page 2. What is Internet? CUSAT is linked to this Web through 10 Mbps leased line connectivity Page 3. Size of the Web? GYWA = Sorted on Google, Yahoo!, Windows Live Search (Msn Search) and Ask YGWA = Sorted on Yahoo!, Google, Windows Live Search (Msn Search) and Ask www.worldwidewebsize.com Page 4. The Machine is Us/ing Us ■ http://in.youtube.com/watch?v=NLlGopyXT_g&feature=channel Page 5. ..

Towards Web 3.0

Page 1. Towards Web 3.0... • Web 1.0 • Web 2.0 • Web 3.0 • Technology hype? • Internet as seen by our kids? Page 2. Random Trivia: Brazil has more Orkut users than citizens Page 3. The war is over. Platforms have won. Applications have lost Page 4. Page 5. Blogosphere • The blogosphere is made up of all blogs and their interconnections Page 6. Social bookmarking Page 7. Page 8. Page 9. Page 10. Page 11. Page 12. Page 13. Page 14. Towards Web 3.0 Page 15. Page 16. Wolfram Alpha Page 17. Page 18. Page 19. Page 20. Page 21. Page 22

Theoretical study of magnetism, structure and chemical order in transition-metal alloy clusters

Research on transition-metal nanoalloy clusters composed of a few atoms is fascinating by their unusual properties due to the interplay among the structure, chemical order and magnetism. Such nanoalloy clusters, can be used to construct nanometer devices for technological applications by manipulating their remarkable magnetic, chemical and optical properties. Determining the nanoscopic features exhibited by the magnetic alloy clusters signifies the need for a systematic global and local exploration of their potential-energy surface in order to identify all the relevant energetically low-lying magnetic isomers. In this thesis the sampling of the potential-energy surface has been performed by employing the state-of-the-art spin-polarized density-functional theory in combination with graph theory and the basin-hopping global optimization techniques. This combination is vital for a quantitative analysis of the quantum mechanical energetics. The first approach, i.e., spin-polarized density-functional theory together with the graph theory method, is applied to study the Fe$_m$Rh$_n$ and Co$_m$Pd$_n$ clusters having $N = m+n \leq 8$ atoms. We carried out a thorough and systematic sampling of the potential-energy surface by taking into account all possible initial cluster topologies, all different distributions of the two kinds of atoms within the cluster, the entire concentration range between the pure limits, and different initial magnetic configurations such as ferro- and anti-ferromagnetic coupling. The remarkable magnetic properties shown by FeRh and CoPd nanoclusters are attributed to the extremely reduced coordination number together with the charge transfer from 3$d$ to 4$d$ elements. The second approach, i.e., spin-polarized density-functional theory together with the basin-hopping method is applied to study the small Fe$_6$, Fe$_3$Rh$_3$ and Rh$_6$ and the larger Fe$_{13}$, Fe$_6$Rh$_7$ and Rh$_{13}$ clusters as illustrative benchmark systems. This method is able to identify the true ground-state structures of Fe$_6$ and Fe$_3$Rh$_3$ which were not obtained by using the first approach. However, both approaches predict a similar cluster for the ground-state of Rh$_6$. Moreover, the computational time taken by this approach is found to be significantly lower than the first approach. The ground-state structure of Fe$_{13}$ cluster is found to be an icosahedral structure, whereas Rh$_{13}$ and Fe$_6$Rh$_7$ isomers relax into cage-like and layered-like structures, respectively. All the clusters display a remarkable variety of structural and magnetic behaviors. It is observed that the isomers having similar shape with small distortion with respect to each other can exhibit quite different magnetic moments. This has been interpreted as a probable artifact of spin-rotational symmetry breaking introduced by the spin-polarized GGA. The possibility of combining the spin-polarized density-functional theory with some other global optimization techniques such as minima-hopping method could be the next step in this direction. This combination is expected to be an ideal sampling approach having the advantage of avoiding efficiently the search over irrelevant regions of the potential energy surface.

Escuela TIC 2.0.

Resumen tomado de la publicación

Come bien, mastica bien : educación bucodental en el niño de 0-3 años.

Guía que pretende informar y sensibilizar sobre la importancia de promocionar la salud bucodental desde edades tempranas, dirigida a profesionales, cuidadores y padres. A través de pequeñas informaciones teóricas ilustradas con fotografías se ofrece una relación de las patologías más frecuentes a estas edades y las pautas para la correcta higiene bucodental que las previene, evitando los malos hábitos en alimentación e higiene.

Guía regional de atención temprana : prevención de deficiencias en la población infantil de 0 a 6 años.

El objetivo de esta guía es fomentar la prevención de deficiencias, permitir un diagnóstico temprano y ofrecer la atención integral a menores que tienen deficiencias o riesgo de padecerlas. La guía se estructura en torno a los siguientes bloques de contenidos: la atención temprana en niños de alto riesgo, desarrollo del niño de 0 a 4 años, signos de alarma en el niño, factores de riesgo socioambiental. En la misma se realiza una exhaustiva relación de los centros de Servicios Sociales y de los centros de Atención Temprana en la Región de Murcia. Los destinatarios de esta Guía de recursos de Atención Temprana son los distintos profesionales (pedagogos, psicólogos, médicos) de este área.

Módulo 0 : primer curso de Educación Infantil (Grupo B) : año académico 2008-09.

Publicación realizada al amparo de los Proyectos de Innovación Educativa tipo A-2, en el contexto de la Convergencia Europea (R-232/2008, de 22 de abril de la Universidad de Murcia), financiados por la Universidad de Murcia y por la Comunidad Autónoma de la Región de Murcia.