The photoemission optogalvanic effect in a Ne-Nd hollow cathode

Laser-induced photoelectric and photoemission optogalvanic effects in a Ne-Nd hollow cathode discharge have been studied using a continuous wave laser source. The potential barrier for photoinduced electron emission from the cathode decreases as the applied voltage is increased. Owing to secondary electron emission in the plasma, the photocurrent is greater than that without discharge. The multiplication of secondary electrons and the quantum efficiency are also investigated.

Subcritical Hopf bifurcation in Ne-Nd hollow cathode discharge

We report the experimental observation of subcritical Hopf bifurcation and the existence of non-oscillating “windows” in the dynamics of a Ne-Nd hollow cathode discharge current as the control parameter.

On the magnetic properties of ultra-Þne zinc ferrites

Zinc ferrite belongs to the class of normal spinels where it is assumed to have a cation distribution of Zn2`(Fe3`)2(O2~)4, and it is purported to be showing zero net magnetisation. However, there have been recent reports suggesting that zinc ferrite exhibits anomaly in its magnetisation. Zinc ferrite samples have been prepared by two di¤erent routes and have been analysed using low energy ion scattering, Mo¬ ssbauer spectroscopy and magnetic measurements. The results indicate that zinc occupies octahedral sites, contrary to the earlier belief that zinc occupies only the tetrahedral sites in a normal spinel. The amount of zinc on the B site increases with decrease in particle size. The LEIS results together with the Mo¬ ssbauer results and the magnetic measurements lead to the conclusion that zinc occupies the B site and the magnetisation exhibited by ultraÞne particles of zinc is due to short range ordering

Threshold scan of the Ne 2s-electron photoionization cross edition

The photoionization of the Ne 2s-electrons was studied from threshold to 1 eV above threshold. The technique of photon-induced fluorescence spectroscopy was applied. Pronounced structures were observed resulting from autoionization of doubly excited atomic states. A threshold cross section of 0.17 Mb was determined.

State-selective study of the direct double photoionization of the Ne valence shell

Cross sections for double photoionization of the Ne L shell into the 2s2p{^5 3}P^0} and ^1P^0 and the 2s^02p^6 ^1S^e states were measured for energies from threshold up to 150 eV, using photon induced fluorescence spectroscopy. Both 2s2p^5 channels were observed with comparable magnitude in contradiction to a propensity rule based on the Wannier-Peterkop-Rau theory. A comparison of the summed ^3P^0 and ^1P^0 cross sections with MBPT calculations results in a deviation of 50%.

Influence of occupation number of single particle levels on K - K charge transfer in collisions of 90 keV - Ne{^9+} on Ne

The influence of the occupation of the single particle levels on the impact parameter dependent K - K charge transfer occuring in collisions of 90 keV Ne{^9+} on Ne was studied using coupled channel calculations. The energy eigenvalues and matrixelements for the single particle levels were taken from ab initio self consistent MO-LCAO-DIRAC-FOCK-SLATER calculations with occupation numbers corresponding to the single particle amplitudes given by the coupled channel calculations.

The Li-like KLL-Auger spectrum of foil excitation Ne-projectiles

KLL-Auger transitions of the three electron system in Ne have been recorded in a coincidence experiment frec of contaminants from other systems. Energies as well as intensities are compared with calculated values.

Many electron coupled channel calculations for the system F{^8+} - Ne

To describe the time dependence of an atomic collision system the Dirac equation usually is rewritten in a coupled channel equation. We first discuss part of the approximation used in this approach and the connection of the many particle with the one particle interpretation. The coupled channel equations are solved for the system F{^8+} - Ne using static selfconsistent many electron Dirac-Fock-Slater wavefunctions as basis. The resulting P(b) curves for the creation of a Ne K-hole are in reasonable agreement with the experimental results.

Compostatge : algunes formes de fer-ne. 'Compostaje : algunas formas de hacerlo'.

Resumen tomado de la revista

Aprofitem els nostres parcs : Traguem-ne suc!. 'Aprovechemos nuestros parques : Saquémosle jugo'.

Se presentan las aplicaciones educativas que puede ofrecer un parque. A partir del estudio del Parque Güell y el Laberinto de Horta se pueden realizar actividades en el aula que sirvan como ejemplo para el uso de otros entornos urbanos.

L'esforç reflexiu de fer-ne, de la vida, una història. 'El esfuerzo reflexivo de hacer, de la vida, una historia'.

Se expone la importancia de las historias de vida como constructoras de la identidad individual. Se intenta descubrir e inventar el yo, como potenciador de un proyecto personal de vida. La identidad se muestra como un concepto esencial en la naturaleza del trabajo de la persona, incluyendo aspectos como las motivaciones, la satisfacción y las competencias.

Lire pour écrire. Je ne suis pas d'acord!. Je cherche, je trouve!. 'Leer para escribir.No estoy de acuerdo!. ­Busco, encuentro!'.

Crédito de lengua francesa para alumnos de ESO. Los objetivos son: acercarse a la realidad francesa mediante contactos directos; describir una situación; dar la opinión y justificarla; escribir correctamente; autoorganizarse colectivamente; expresar los sentimientos propios y los deseos; identificar las funciones de un texto y encontrar las principales informaciones; dirigirse al grupo-clase en lengua francesa y escribir una carta. Se divide en 2 dosieres: estados de ánimo y sentimientos e introducción a una lectura activa, cada uno con sus correspondientes actividades.

De la infecció pel VIH-Sida parlem-ne amb Bristol-Myers. 'Hablemos de la infección por VIH-Sida con Bristol-Myers'.

Resumen del autor en catalán

Reflexionem sobre la llengua per millorar-ne l'??s

Resumen basado en el de la publicaci??n

Per saber-ne m??s sobre narracions visuals

Resumen basado en el de la publicaci??n