References of "Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms"
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See detailThe recognition of biological cells utilizing quantitative phase microscopy system
Veselov, O.; Lekki, J.; Polak, W. et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2005), 231

Single ion bombardment of biological cells using an ion microprobe is a promising technique. However, for microprobe investigations of biological processes at a cellular level the precise recognition of a ... [more ▼]

Single ion bombardment of biological cells using an ion microprobe is a promising technique. However, for microprobe investigations of biological processes at a cellular level the precise recognition of a single cell and particularly of its nucleus is required. Moreover, cells must be examined in their natural state and environment (i.e. without previously being killed, preferentially not fixed nor stained) and, also, the use of ultraviolet light for cells observation should be avoided. Additionally, in order to obtain statistically significant results of irradiation, the possibility of fast automatic recognition of thousands of objects must be provided. Because computer recognition strongly depends on the quality of an image, the optical imaging system is of crucial importance. For this purpose one of the best solutions could be the Quantitative Phase microscopy (QPm) technique. QPm is the recent digital technique of phase contrast microscopy, providing quantitative phase and intensity data obtained from a series of defocused images. The following phase contrast modalities may be generated digitally from the computed QPm phase data with a greater degree of flexibility: Pure phase images (intensity-free), standard phase contrast (e.g. Zernike phase contrast), differential interference contrast (DIC), Hoffman modulation contrast, and simulated darkfield. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailRoughness evolution of some X-UV reflective materials induced by low energy (< 1 keV) ion beam milling
Gailly, Patrick ULg; Jamar, Claude ULg; Fleury-Frenette, Karl ULg et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2004), 216

Ion beam figuring (IBF) is an advanced technique that is been used for more than 10 years as a final step in the manufacturing of optical elements. It makes use of ion sputtering to correct shape defects ... [more ▼]

Ion beam figuring (IBF) is an advanced technique that is been used for more than 10 years as a final step in the manufacturing of optical elements. It makes use of ion sputtering to correct shape defects but this process may eventually lead to the degradation of the surface roughness. In this study, the evolution of roughness for some optical materials subjected to the ion beam figuring process has been investigated by using optical profilometry and scanning electron microscopy. Emphasis has been made on electroplated nickel, PVD gold and CVD silicon carbide. These materials are often used for X-ray and UV applications but only limited data on their behavior under ion milling is currently available. Roughness measurements have been performed at different etching depths down to 5 mum which is representative of typical IBF treatments. The effects of using different inert gases (Ar, Kr and Xe) with ion energies ranging from 200 to 900 eV have been studied. The observed trends are an important increase of the roughness for electroplated nickel, a slight decrease for PVD gold and a slight increase for CVD silicon carbide. Results are discussed in relation to previous related works and within sputtering considerations. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailReal time RBS study of Cu-Sn alloy thermal oxidation by means of a 4He2+ external micro-beam
Mathis, François ULg; Salomon, Joseph; Moignard, Brice et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2004), 226

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See detailStudy of color centers induced by PIXE irradiation
Absil, J.; Garnir, Henri-Pierre ULg; Strivay, David ULg et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2002), 198(1-2), 90-97

The particle induced X-ray emission method is perfectly adapted to the study, by external beam, of art objects (like paintings) and allows non-destructive analysis of the atomic composition of the target ... [more ▼]

The particle induced X-ray emission method is perfectly adapted to the study, by external beam, of art objects (like paintings) and allows non-destructive analysis of the atomic composition of the target. However, a strange phenomenon occurs during irradiation on some pigments: dark brownish stains appear, and this could be due to the formation of color centers. In fact, these darkening spots progressively fade out and disappear after a few weeks. Heat and UV light accelerate the decreasing process. The aim of this study is to understand the physical processes of the stain creation and to find a way to make stains disappear, avoiding any damage for the painting. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailAn empirical formula for L line X-ray production cross-section of elements from Ag to U for protons below 3.5 MeV
Strivay, David ULg; Weber, Georges ULg

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2002), 190

When computing element concentration from proton induced X-ray emission analysis, an important parameter is the X-ray production cross-section. There have been numerous experimental and theoretical works ... [more ▼]

When computing element concentration from proton induced X-ray emission analysis, an important parameter is the X-ray production cross-section. There have been numerous experimental and theoretical works in this field. Nonetheless, although there is a simple analytical formula to compute K X-ray cross-sections, there is no such ones for the L lines. We present here analytical formulas for the cross-section of the three main X-ray lines L-alpha L-beta and L-gamma based on experimental data. So far, nearly 3000 values of cross-sections for elements from Ag to U and proton energy ranging from 0.5 to 3.5 MeV have been collected from various references. This experimental data set has been fitted for each Xray line with an exponential function depending on the proton energy and on the element atomic number. These fitted values have then been compared to the experimental data and with theoretical values obtained by the ECPSSR theory and Coster-Kronig fluorescence yields. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailUse of PIXE-PIGE under variable incident angle for ancient glass corrosion measurements
Weber, Georges ULg; Strivay, David ULg; Martinot, Lucien et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2002), 189

Although glass is usually considered as a very stable archaeological material, it can undergo severe degradation. Soda-lime glass, the most common glass throughout ancient times, is particularly sensitive ... [more ▼]

Although glass is usually considered as a very stable archaeological material, it can undergo severe degradation. Soda-lime glass, the most common glass throughout ancient times, is particularly sensitive to this problem. The glass surface absorbs moisture from its environment and the contact with CO2 causes Na2O and NaOH to convert to Na2CO3, which is extremely hygroscopic. The subsequent unstable glass layer can be leached out and causes decomposition of the glass. The non-destructive PIGE-PIXE method of investigation allows detection of this phenomenon even if no visible effect appears. The variable incident angle method is able to discern the depth of the degradation. One aim of such studies is the possible dating or at least fake detecting of archaeological materials, Furthermore, even objects of large size can be investigated with the atmospheric PIGE-PIXE Set-LIP, Some examples of measurements on ancient glass are given. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailIn situ dynamic analysis of solid or aqueous solutions undergoing chemical reactions by RBS or PIXE with external beam
Bouquillon, A.; Dran, J*-C; Lagarde, G. et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2002), 188

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See detailEquilibrium charge-state distributions of sodium ions in carbon foil
Tordoir, Xavier ULg; Bastin, Thierry ULg; Dumont, Paul-Dominique ULg et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2001), 173

The equilibrium charge-state distributions have been measured for sodium ions at the exit of a carbon foil for energies ranging from 0.43 to 1.66 Me V. A comparison of our results with available models is ... [more ▼]

The equilibrium charge-state distributions have been measured for sodium ions at the exit of a carbon foil for energies ranging from 0.43 to 1.66 Me V. A comparison of our results with available models is performed and an empirical formula for calculating the charge-state fractions of sodium ions is deduced. [less ▲]

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See detailUse of a variable incidence angle PIXE arrangement for studying pigment multilayers
Weber, Georges ULg; Delbrouck, J. M.; Strivay, David ULg et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (1998), 139(1-4), 196-201

Particle induced X-ray emission (PIXE) method is used in the field of archeometry and specially to investigate pigment colored multilayers. The tilting of the sample with respect to the incident proton ... [more ▼]

Particle induced X-ray emission (PIXE) method is used in the field of archeometry and specially to investigate pigment colored multilayers. The tilting of the sample with respect to the incident proton beam direction allows to modify the relative contribution of each layer to the fluorescence signal. The experimental results coupled to computer simulations lead to semi-quantitative information about the thickness, the position and the composition of the successive layers. (C) 1998 Elsevier Science B.V. [less ▲]

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See detailAutomatic external filling for the ion source gas bottle of a Van de Graaff accelerator
Bastin, Thierry ULg; Dehove, C.; Dumont, Paul-Dominique ULg et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (1997), 129

We describe a fully automatic system we developed to fill, from an external gas bottle, the ion sourer terminal gas storage bottle of a 2 MV Van de Graaff accelerator without depressing the 25 bar ... [more ▼]

We describe a fully automatic system we developed to fill, from an external gas bottle, the ion sourer terminal gas storage bottle of a 2 MV Van de Graaff accelerator without depressing the 25 bar insulating gas. The system is based on a programmable automate ordering electropneumatical valves. The only manual operation is the connection of the external gas cylinder. The time needed for a gas change is reduced to typically 15 min (depending on the residual pressure wished for the gas removed from the terminal bottle). To check this system we study the ionic composition of the ion beam delivered by our accelerator after different gas changes. The switching magnet of our accelerator was used to analyse the ionic composition of the accelerated beams in order to verify the degree of elimination of the previous gases in the system. (C) 1997 Elsevier Science B.V. [less ▲]

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See detailUse of PIXE to measure serum copper, zinc, selenium, and bromine in patients with hematologic malignancies
Beguin, Yves ULg; Bours, Vincent ULg; Delbrouck, J.-M. et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (1990), B49

The use of PIXE allowed for a simultaneous determination of serum copper (Cu), zinc (Zn), selenium (Se) and bromine (Br), in various groups of patients with hematologic malignancies. In 78 patients with ... [more ▼]

The use of PIXE allowed for a simultaneous determination of serum copper (Cu), zinc (Zn), selenium (Se) and bromine (Br), in various groups of patients with hematologic malignancies. In 78 patients with acute nonlymphocytic leukemia, it was observed that (1) serum Se was significantly lower than in healthy controls and correlated inversely with the tumor burden; (2) serum bromine was normal at diagnosis but dropped dramatically after intensive chemotherapy, before recovering progressively over a period of months; and (3) pretreatment serum copper and zinc were significant prognotic factors of the chance to achieve a complete remission. In 50 patients with chronic lymphocytic leukemia, it was observed that (1) serum Cu and Cu/Zn ratio were useful indices of the disease activity, which were independent of a nonspecific acute phase reaction; and (2) Zn deficiency could contribute to immune dysfunction. In 119 patients with myeloproliferative disorders or myelodysplasic syndromes, serum Cu and Zn levels were mostly dependent on nonspecific factors, such as age and inflammation. [less ▲]

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See detailTrace element analysis by PIXE in several biomedical fields
Weber, G.; Robaye, G.; Bartsch, P. et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (1984), B3

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