Search results for "Ph. D."
showing 10 items of 180 documents
Doubly Magic NucleusHs162108270
2006
Theoretical calculations predict $^{270}\mathrm{Hs}$ ($Z=108$, $N=162$) to be a doubly magic deformed nucleus, decaying mainly by $\ensuremath{\alpha}$-particle emission. In this work, based on a rapid chemical isolation of Hs isotopes produced in the $^{26}\mathrm{Mg}+^{248}\mathrm{Cm}$ reaction, we observed 15 genetically linked nuclear decay chains. Four chains were attributed to the new nuclide $^{270}\mathrm{Hs}$, which decays by $\ensuremath{\alpha}$-particle emission with ${Q}_{\ensuremath{\alpha}}=9.02\ifmmode\pm\else\textpm\fi{}0.03\text{ }\text{ }\mathrm{MeV}$ to $^{266}\mathrm{Sg}$ which undergoes spontaneous fission with a half-life of ${444}_{\ensuremath{-}148}^{+444}\text{ }\t…
Resonant laser ionization of polonium at rilis-isolde for the study of ground- and isomer-state properties
2008
Three new ionization schemes for polonium have been tested with the resonant ionization laser ion source (RILIS) during the on-line production of 196Po in a UCx target at ISOLDE. The saturation of the atomic transitions has been observed and the yields of the isotope chain 193–198,200,202,204Po have been measured. This development provides the necessary groundwork for performing in-source resonant ionization spectroscopy on the neutron-deficient polonium isotopes (Z = 84). ispartof: Nuclear Instruments & Methods in Physics Research B vol:266 issue:19 pages:4403-4406 ispartof: location:FRANCE, Deauville status: published
Les évolutions du système d'innovation et le marché du travail des jeunes scientifiques
2004
In France, as in many other OECD countries, a sharp increase in the number of Ph.D. graduates in S&E fields from the mid-1980s to the mid-1990s was followed by a decrease in the enrolments in Ph.D. studies. Important transformations in the innovation processes were also observed on the same period. Our hypothesis is that we assist to the emergence of an intermediate scientific labour market between the traditional academic sector and the private research sector. A detailed analysis of the production processes of scientists and of the scientific careers of young scientists is first carried out in the perspective of labour economics. Then, in the perspective of the economics of innovation and…
Precision electroweak measurements on the Z resonance
2005
We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLD experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, $\MZ$ and $\GZ$, and its couplings to fermions, for example the $\rho$ parameter and the effective electroweak mixing angle, are precisely measured. The number of light neutrino species is determined to be 2.9840…
Electroweak measurements in electron-positron collisions at W-boson-pair energies at LEP
2013
The ALEPH, DELPHI, L3, OPAL collaborations and LEP Electroweak Working Group.-- arXiv:1302.3415
Dichrorampha dinarica, new species, a century of confusion in European lepidopterology (Lepidoptera: Tortricidae) resolved by combining morphology an…
2012
Dichrorampha dinarica, new species, is described from the Dinaric mountains (Macedonia, Bosnia and Herzegovina). The newspecies was formerly confused with D. ligulana (Herrich-Schäffer, 1851) from the Alps and D. rilana Drenowsky, 1909 fromthe Rila mountains (Bulgaria). Therefore, a re-description of D. rilana is provided based on topotypical specimens. The diag-nostic morphological characters of the involved species, supported by significant divergence of the mtDNA barcode (COI fragment of 658 bp), are discussed in detail.
New biostratigraphic data from the Ladinian pelagic limestones of Pizzo di Sant’Otiero - Madonie Mountains, Sicily
2014
New biostratigraphic data, based on conodont investigations, were collected from the Ladinian limestones recently described at Sant’Otiero, a locality near the Village of Petralia Sottana in the Madonie Mountains (Central-Northern Sicily). At this locality a new calcareous succession lying at the base of a major tectonic unit of the Maghrebian chain is described. This succession consists of a lower massive part formed by a carbonate megabreccia, the elements of which are shallow water extraclasts with dasycladalean algae (Diplopora annulatissima Pia), benthic foraminifers, “Tubiphytes” and problematic organisms commonly described from Anisian carbonate platforms. Upward a well-bedded succes…
Fragmentation and Coverage Variation in Viral Metagenome Assemblies, and Their Effect in Diversity Calculations
2015
Metagenomic libraries consist of DNA fragments from diverse species, with varying genome size and abundance. High-throughput sequencing platforms produce large volumes of reads from these libraries, which may be assembled into contigs, ideally resembling the original larger genomic sequences. The uneven species distribution, along with the stochasticity in sample processing and sequencing bias, impacts the success of accurate sequence assembly. Several assemblers enable the processing of viral metagenomic data de novo, generally using overlap layout consensus or de Bruijn graph approaches for contig assembly. The success of viral genomic reconstruction in these datasets is limited by the de…
«Bella mia fiamma, addio / Resta, o cara» tra Jommelli e Mozart: osservazioni e ipotesi sull’aria K. 528
2012
Mozart wrote the scena and aria K. 528 in Prague in 1787 for the singer Josepha Duschek. As previously known, this wonderful page is based on a text taken from “Cerere placata”, a “festa teatrale” created in Naples in 1772 by the man of letters and scientist Michele Sarcone and the renowned “maestro di cappella” Niccolò Jommelli to celebrate the birth of the first daughter of king Ferdinand IV of Bourbon. The article reconstructs in detail the circumstances of the Neapolitan performance, and shows that Jommelli’s setting of Titano’s recitative and aria “Bella mia fiamma, addio” / “Resta, o cara; acerba morte” enjoyed a large success and circulated as an autonomous piece. A comparison betwee…
Studies of 225,226U alpha decay chains
2001
Studies of 225,226U α -decay chains produced via heavy ion induced fusion reactions of 22Ne + 208Pb → 230U and of 18O + 208Pb → 226Th were carried out using the JYFL gas-filled magnetic recoil separator RITU. The data obtained for α -decays of 225,226U, 221,222Th, 218Ra and 213Rn concerning their α -particle energies, half-lives and α -decay fine structures are compared to previous investigations. peerReviewed