No abstract available

[en] The applications of X-ray photoelectron spectroscopy in biochemistry, organic and inorganic chemistry, elemental and trace analysis are indicated, as well as in polymer chemistry and quantitative analysis, after a short introduction to the basics of the technique has been given

[en] Auger first experiences in 1923 and thesis in 1926 on photoelectrons with a Wilson chamber are shortly presented. The two related techniques, Siegbahn XPS (X-ray Photoelectron Analysis) and Auger AES (Auger Electron Spectroscopy), are compared for surfaces analysis with advantages and disadvantages. (A.B.). 13 refs., 3 figs

[en] This paper presents Auger electron spectroscopy with a retarding field analyser designed for an advanced physics experiment carried out in 'Physics Laboratory II' at the Institute of Experimental Physics, University of Wroclaw, Poland. The authors discuss the process of setting up the experiment and the results of the measurement of Auger spectra. The advantages and disadvantages of the apparatus are discussed along with its implementation in the teaching process

[en] A background correction method based on wavelet transform was devised and applied to inductively coupled plasma atomic emission spectrometry (ICP-AES). The proposed approach separated background from analyte signal according to their different frequencies. Compared with the analyte signal, the background has a low frequency. By removal of the components attributed to the signal, the background over the spectral window of the analyte line can be fitted through wavelet reconstruction. The results showed that the wavelet transform technique could handle all kinds of background and low signal-to-background ratio spectra, and required no prior knowledge about the sample composition, no selection of suitable background correction points, and no mathematical assumption of the background distribution. This technique performed as well as the conventional three-point background correction method for linear backgrounds, and provided better results than the latter for curved backgrounds. The proposed procedure was illustrated, by processing real spectra, to be an effective and practical tool for background correction in ICP-AES

No abstract available

[en] We report Akebono observations of anisotropic electron velocity distributions in the sunlit polar wind, in which the averaged energy (temperature) of the thermal energy electrons is higher in the upward magnetic field direction than in the downward and perpendicular directions. In the 1500-4000 km altitude region, the observed upward to downward temperature ratio, T_eu/T_ed, was in the range of 1.5 to 2. The observed downward and perpendicular temperatures were similar; T_ed/T(e perpendicular)≅1. The heat flux associated with the observed thermal energy electron velocity distribution was upward and on the order of ∼10^-2 erg cm^-2s^-1, and was a factor of 5 larger than that of the atmospheric photoelectrons above 10 eV. In this altitude region, the higher-energy (> a few eV) photoelectrons are essentially collisionless. In contrast, the ambient and lower-energy photoelectrons remain collisional because of their larger Coulomb collision cross sections. In the steady state, an ambipolar electric field is required to maintain quasi-neutrality along the field line. It is suggested that the ambipolar electric field and the Coulomb collisions modify the velocity distributions of the thermal energy electrons and the photoelectrons, resulting in the observed temperature anisotropy. The upward heat flux associated with the observed temperature anisotropy dominates any downward heat flux due to electron temperature gradients that may be present in the polar wind plasma and demonstrates the important role of the photoelectrons in the dynamics of the polar wind. 49 refs., 6 figs

[en] After recalling the general principles, experimental techniques are described: analyzers, detection methods, techniques of imaging and practical problems. In conclusion applications are reviewed including qualitative and quantitative analysis, concentration profiles and industrial applications

[en] Beginning with a chapter on symmetry and invariance, the theory of the Auger process is developed by considering the progressive breaking of symmetry as one goes from the simple hydrogenic model to a more realistic description of the many-electron atom. The calculation of Auger intensities and energies using different coupling schemes is also discussed from this angle, the results of important calculations are compared with experiment, and recent work on Auger satellites and correlation effects is reviewed. With a conscious departure from the emphasis on theory, the last chapter deals with surface Auger phenomena: after a brief survey of analytical methods, it described the features of Auger spectra in solids and gives a critical account of the principal aspects of surface Auger spectroscopy

[en] Variation trends across the AnO₂ series of An5f-electron covalent bonding and An5f→O3s, O2p→An5f charge transfer energies, are studied using DV-Xα relativistic spin-polarised computation of electronic structures applied to 11 'AnO₈' clusters, from ThO₈ to FmO₈. It is found that the binding energies of 5f orbitals, therefore the An5f-O2p hybridisation, are increasing though the 5f orbitals are localising across the An series. In our calculations, the 3s and 3p ionic-like orbitals of O^2- ions are included for the first time as LCAO-MO bases. Then, the conduction band is a mixing of O3s and An6d and its lower edge corresponds to an O3s-dominated state. Moreover, the calculated charge transfer (CT) energies of An5f→O3s and O2p→An5f transitions show the so-called tetrad effect when CT energies, respectively increasing and decreasing across the AnO₂ series. It is pointed out that the tetrad effect here comes mainly from the special spin-polarised pattern of 5f levels and the increasing general trend of 5f binding energies. (orig.)