Angular distributions of ions emitted from laser plasma produced at various irradiation angles and laser intensities

AbstractAngular distributions of currents and velocities (energies) of ions produced at various target irradiation angles and laser intensities ranged from 1010 W/cm2 to 1017 W/cm2 were analyzed. It was confirmed that for low laser intensities the ion current distributions are always peaked along the target normal. However, at laser intensities comparable to or higher than 1014 W/cm2, the preferred direction of ion emission strongly depends on the irradiation geometry (laser focus setting, the irradiation angle), and can be off the target normal. This is very likely caused by the non-linear interaction of the laser beam with produced plasma, in particular, by the action of ponderomotive forces and the laser beam self-focusing

The influence of an intense laser beam interaction with preformed plasma on the characteristics of emitted ion streams

AbstractIntense laser-beam interactions with preformed plasma, preceding the laser-target interactions, significantly influence both the ion and X-ray generation. It is due to the laser pulse (its total length, the shape of the front edge, its background, the contrast, the radial homogeneity) as well as plasma (density, temperature) properties. Generation of the super fast (FF) ion groups is connected with a presence of non-linear processes. Saturated maximum of the charge states (independently on the laser intensity) is ascribed to the constant limit radius of the self-focused laser beam. Its longitudinal structure is considered as a possible explanation for the course of some experimental dependencies obtained

An evaluation of family physicians' educational needs and experiences in health promotion and disease prevention in Poland and Lithuania - a qualitative study

Reikšminiai žodžiai: Ligų prevencija; Sveikatos stiprinimas; Šeimos gydytojai; Šeimos gydytojų rengimas; Šeimos gydytojų švietimo poreikiai; Disease prevention; Family physicians; Family physicians educational needs; Health promotion; Training of family physician

Top-down and bottom-up approach to competence management implementation: A case of two central banks

The primary aim of this paper is to evaluate the contribution that competence based approaches to staff management can and ought to make to the overall effectiveness of organisations. The importance of competencies and their proper management is broadly acknowledged in the literature, and the first part of the paper is a literature review. This is followed with a comparison of the design and implementation of two competence management projects that were introduced in two central banks, one of a western European nation, and the other of a central European nation. There is a brief presentation of two fundamental approaches to competence management implementation in organization (top-down (directive) and bottom-up (participative)), and this is juxtaposed with the actual implementation of competence management model that took place in two central banks. What ensues from the comparison is the identification of potential threats to the implementation of competence management models in organizations, accompanied by suggestions on how to counteract them.O objetivo principal deste trabalho é avaliar o contributo que as abordagens baseadas nas competências na gestão do pessoal pode e deve dar para a eficácia global das organizações. A primeira parte do artigo faz uma revisão da literatura, na qual a importância das competências e da sua correta gestão é amplamente reconhecida. Segue-se uma comparação entre o desenho e implementação de dois projetos de gestão de competências que foram introduzidas em dois bancos centrais, um de um país da Europa Ocidental e outro de um país da Europa Central. Há uma breve apresentação de duas abordagens fundamentais para a implementação da gestão de competências numa organização (top-down (diretiva) e bottom-up (participativa)), sendo isto justaposto com a implementação do modelo de gestão de competências que ocorreu em dois bancos centrais. O que resulta da comparação é a identificação de ameaças potenciais à implementação de modelos de gestão de competências nas organizações, acompanhada de sugestões sobre a forma de neutralizá-las

Implantation and sputtering of ge and si ions into SiO2 substrates using electric fields for acceleration and optimisation of laser-produced Ion streams used for modification of semiconductor materials

Laser plasma has been proved to be a potential source of multiply charged ions which could support the growing demands for high-current ion beams. To optimize efficiency of the ion implantation technology selection of proper laser beam characteristics is very important and should be investigated. With LIS, several variables can and must be controlled. The properties of ions (current densities, the ion charge state, angular and energy distributions) depend on target material and the laser energy, pulse duration and intensity on the target surface. So, the characteristics of laser-produced ion streams should be determined with the use of precise ion diagnostic methods. Based on the preliminary results for acceleration of ions produced with the use of a repetitive laser system at IPPLM the special electrostatic-acceleration system has been designed and prepared. This device permits to accelerate ions having charge states of 1+ to energies up to ∼40 keV. The movable target holder was located inside the cylindrical box connected with a high-voltage source (up to 50 kV at 50 mA). The accelerated Ge and Si ions was implanted to SiO2/Si substrates and analyzed. This contribution is concerned mainly on the analysis and optimization of laser-produced Ge and Si ion streams as well as on investigation of the direct implantation of these ions into SiO2 substrates. Targets were irradiated with the use of repetitive (up to 10 Hz) laser with energy up to 700 mJ in one pulse, at radiation intensities of ∼1011 W/cm2. The ion stream parameters were measured using the time-of-fight method. The depth of ion implantation was determined by X-Ray Photoelectron Spectroscope (XPS). After the implantation the samples were annealed in different temperatures in range of to create nanocrystal structures and then analyzed by means of Raman Spectroscopy, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The work has been performed within SEMINANO project supported by EC (within 6FP)