Search results for "Toe"

Magnetic Domain Imaging with a Photoemission Microscope

1997

ABSTRACTPhotoelectron emission microscopy (PEEM) has proven to be a versatile analytical technique in surface science. When operated with circularly polarized light in the soft x-ray regime, however, photoemission microscopy offers a unique combination of magnetic and chemical information. Exploiting the high brilliance and circular polarization available at a helical undulator beamline, the lateral resolution in the imaging of magnetic domain structures may be pushed well into the sub-micrometer range. Using a newly designed photoemission microscope we show that under these circumstances not only domains, but also domain walls can be selectively investigated. The high sensitivity of the te…

Optical and structural studies of GaN 3D structures selectively grown by MOCVD

2004

Abstract This paper presents preliminary results on the selective growth of three-dimensional (3D) micrometric metallic structures by the MOCVD technique. The 3D structure growth occurs by simply feeding the reactor gas phase with a conventional flow of metal-organic (MO), trimethyl-gallium (TMGa) molecules. Selectivity occurs at the substrate surface in which MO species travel tens of micrometers in order to build up the 3D structure. After the growth, these structures are nitrided in order to give GaN-related optical visible emission. Optical emission results are presented and discussed in this paper. Both 3D structures deposition and annealing experiments can be extended to other III–V m…

Watching Ions Move: Scanning Probe Microscopy on Perovskite Solar Cells

2018

Electron Angular Distribution in Laser-Assisted X-ray Photoeffect

1981

Calculations are reported of the differential cross section of the laser-assisted X-ray photoeffect from K shells showing that drastic changes occur in the shape of the ejected-electron angular distribution when laser photons are exchanged during the ionisation. This process appears well suited to the study of laser effects and multiphoton exchanges in laser-assisted atomic collisions.

Experimental demonstration of an ultrafast all-optical bit-error indicating scheme

2010

International audience; We experimentally demonstrate an all-optical bit error monitoring scheme based on the self-phase modulation occurring during the propagation in a highly nonlinear fiber followed by an optical bandpass filter. Numerical simulations are confirmed by experimental observations performed at a repetition rate of 40 Gb/s.

Logic gates scheme based on Coulomb blockade in metallic nanoclusters with organic ligands

2010

We propose a logic gates scheme based on the electron transfer through metallic nanoclusters linked to organic ligands and discuss theoretically the characteristics needed for practical implementation. As a proof-of-the-concept, we demonstrate the OR, AND and NOT gates and study the performance in terms of temperature, applied voltage, and noise.

The Influence of School Climate and Family Climate among Adolescents Victims of Cyberbullying

2016

El ciberacoso es un fenómeno de creciente preocupación social que afecta cada vez más a niños y adolescentes de todos los paí- ses desarrollados. A diferencia de la considerable literatura que hay sobre las relaciones entre el acoso escolar y el contexto familiar y escolar, todavía hay pocos trabajos sobre la influencia de estos entornos sociales en el problema del ciberacoso. Mediante una metodología cuantitativa, el objetivo principal del presente estudio fue analizar la influencia del contexto escolar y familiar en víctimas de ciberacoso. La muestra estuvo formada por 1.062 adolescentes (51,5% chicos y 48,5% chicas), de edades comprendidas entre los 12 y los 18 años (M=14,5; DT=1,62). Se…

Diversity and composition of the microbiome associated with eggs of the Southern green stinkbug, Nezara viridula (Hemiptera: Pentatomidae).

2022

Although microbial communities of insects from larval to adult stage have been increasingly investigated in recent years, little is still known about the diversity and composition of egg-associated microbiomes. In this study, we used high-throughput amplicon sequencing and quantitative PCR to get a better understanding of the microbiome of insect eggs and how they are established using the Southern green stinkbug Nezara viridula (L.) (Hemiptera: Pentatomidae) as a study object. First, to determine the bacterial community composition, egg masses from two natural populations in Belgium and Italy were examined. Subsequently, microbial community establishment was assessed by studying stinkbug e…

Sensitivity of SHG-FROG for the characterization of ultrahigh-repetition-rate telecommunication laser sources

2004

International audience; We analyze experimentally the sensitivity of second-harmonic generation frequency-resolved optical gating (SHG-FROG) for the complete intensity and phase characterization of both a sinusoidal beat signal and a train of 1.3 ps pulses at a repetition rate of 160 GHz at 1550 nm. Using a commercially-available optical spectrum analyzer in the SHG-FROG set-up, incident pulses with energies of only 125 and 190 fJ, which correspond to the beat signal and the 1.3 ps pulse train, respectively, have been accurately characterized.

Influence on self-efficacy of the degree of authenticity of the inquiry carried out in two secondary school science projects

2021

Las creencias sobre la propia capacidad para llevar a cabo con exito una tarea concreta (autoeficacia) influyen en la implicacion y la motivacion hacia dicha tarea. En las ultimas decadas se ha incrementado el foco de atencion hacia estas creencias en el area de ciencias no solo como uno de los predictores mas consistentes del desempeno real del alumnado, sino por la existencia de desigualdades sistematicas en la autoeficacia de chicos y chicas. Aunque el Aprendizaje Basado en Proyectos (ABP) en el aula de ciencias posee diversas caracteristicas que potencialmente pueden contribuir a la mejoria de la autoeficacia en ciencias del alumnado, las evidencias entre la relacion de los elementos de…