4,101 research outputs found
A primer on innovation and growth
No full textPhilippe Aghion emphasises that for Europe to stimulate innovation and growth, it is not enough to increase spending on research and development and the protection of intellectual property.
Initial steps towards lithium quantification by electron probe microanalysis
No full textInternational audienceElectron probe microanalysis (EPMA) has established itself as a reliable and widely used technique for non-destructive and precise material characterization in diverse scientific and industrial applications. Despite the growing interest in lithium (Li) and the need for accurate non-destructive analysis at a micron scale, the quantification of Li using EPMA faces persistent challenges. Although recently developed periodic multilayers allow spectroscopy in the energy range around the characteristic Li K emission (~50 eV) [1,2], the detection and quantification of Li using a commercialized microprobe equipped with a bent crystal spectrometer without diffraction gratings has not been successfully performed yet.The complexity of Li detection is due to several factors: the fluorescence yield of Li is low, i.e., few characteristic photons are produced by the decays of the Li 1s core hole, favoring the emission of Auger electrons. Further, the energy of the emitted photons is extremely low, causing strong absorption and weak photon intensity detection. Moreover, the emission undergoes chemical shift and peak-shape changes as the Li K emission band (2p – 1s transition) involves valence electrons, which introduces a dependency on the density of states (DOS) in the valence band [3,4]. This makes the technique highly sensitive to the chemical state of lithium atoms, complicating quantitative analysis further. This work presents promising results of quantitative EPMA of Li in different materials, including battery compounds, metal alloys and ceramics with Li concentrations down to 4 %. The advances were facilitated by the integration of a new detection system, combined with improvements on the quantification procedure using real standards and correction programs adapted to low-voltage EPMA.While additional investigation is required, these first results are promising for researchers focusing on lithium characterization. We demonstrate that EPMA emerges as a potential candidate for quantitative Li analysis, even if the Li is contained in heavy matrices with elements showing emission bands in the same spectral range as Li. This novel Li quantification method can be more accessible than techniques employing synchrotron radiation and is a cost-effective alternative to detection using a scanning electron microscope or an electron microprobe equipped with diffraction gratings.[1] Polkonikov, V., Chkhalo, N., Pleshkov, R., Giglia, A., Rividi, N., Brackx, E., Le Guen, K., Ismail, I., Jonnard, P., Periodic Multilayer for X-ray Spectroscopy in the Li K Range. Appl. Sci. 2021, 11, 6385. https://doi.org/10.3390/app11146385[2] Hassebi, K.; Meltchakov, E.; Delmotte, F.; Giglia, A.; Jonnard, P. Sc/SiC/Al Multilayer Optimization for Li K Spectroscopy. Appl. Sci. 2024, 14, 956. https://doi.org/10.3390/app14030956[3] Schweizer, P., Brackx, E., Jonnard, P., X-Ray Spectrom. 2022, 51 (4), 403. https://doi.org/10.1002/xrs.3290 [4] Hassebi, K., Le Guen, K., Rividi, N., Verlaguet, A., Jonnard, P., X-Ray Spectrom 2023, 52(6), 330. https://doi.org/10.1002/xrs.332
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Letter to Philippe-Antoine Merlin, 1802 November 12.
No full textLetter to Philippe-Antoine Merlin, concerning a conflict involving charges of plagarism between the author and C. Laucuouque, dated "21 brumaire, an 11." The author's signature is not entirely legible. Accompanying enveloped shows traces of red wax seal
Histoire de la Deuxième Guerre Mondiale (1992-1997) (09). Philippe Burrin (1) - face B
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin
Histoire de la Deuxième Guerre Mondiale (1992-1997) (09). Philippe Burrin (1) - face A
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin
Histoire de la Deuxième Guerre Mondiale (1992-1997) (10). Philippe Burrin (2) - face B
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin (suite)
Histoire de la Deuxième Guerre Mondiale (1992-1997) (10). Philippe Burrin (2) - face A
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin (suite)
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Episode #7: Philippe Sands, From Genocide to Ecocide
No full textThis special episode of Borderlines features influential educator, commentator, and litigator Philippe Sands discussing ground-breaking efforts to introduce ecocide – the crime of environmental destruction – into international legal arenas. Philippe Sands QC is Professor of Law at University College London, Pisar Visiting Professor of Law at Harvard, and a barrister at Matrix Chambers. He practises as Counsel before international courts and tribunals. His teaching areas include public international law, the settlement of international disputes including arbitration, and environmental and natural resources law. Philippe is the author of many books, including East West Street: On the Origins of Crimes Against Humanity and Genocide (2016) and The Last Colony, forthcoming in September 2022. Philippe recently co-chaired an independent expert panel which proposed in June 2021 that a new, fifth crime of ecocide be adopted into the Rome Statute of the International Criminal Court. In Episode Seven of Borderlines, listeners will learn about the relationship between ecocide and existing crimes, historic legal and political definitions of genocide being played out today, and the role of courts in enforcing awards and judgments against even Goliath polluters and aggressors. Borderlines from Berkeley Law is a podcast about global problems in a world fragmented by national borders. Our host is Katerina Linos, Tragen Professor of International Law and co-director of the Miller Institute for Global Challenges and the Law. </p
A Primer on Innovation and Growth. Bruegel policy brief 2006/06, October 2006
No full textSummary. In sharp contrast with the post-war period, over the last 10 years income per head in the EU has begun to decline in comparison to that of the US. Against this background, the revival of growth and productivity has become an overriding priority of European policymakers. While fostering innovation has become a necessity in Europe, R&D investments alone will not do the job
Spectroscopy, electronic structure and quantification attempt in the spectral range of the Li Kα emission band
No full textIn this work, we present the way we perform high-resolution wavelength-dispersive X-ray spectrometry in the ultra-soft X-ray range. For this purpose, we use a reflection zone plate spectrometer working, as a variable line spacing grating spectrometer, in the 40 - 110 eV spectral range. We show that the shape of the emission bands can be reproduced by simulation of spectra obtained from the local and partial density of states calculated with the density functional theory. The knowledge of the electronic structure of the material under consideration is important to properly interpret the spectra, which can be complicated when many elements are present in the sample, such as the amblygonite phosphate. We also show the first attempt of elemental quantification of an AlCuLi alloy from intensities measured with the reflection zone plate spectrometer. The obtained mass fractions are in good agreement with those obtained in a standard way from measurements performed in the soft X-ray range with crystal spectrometers
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