Search results for "Penn"
showing 10 items of 568 documents
Comparative high-resolution chemostratigraphy of the Bonarelli Level from the reference Bottaccione section (Umbria-Marche Apennines) and from an equ…
2006
The Bonarelli Level (BL) from the upper Cenomanian portion of the reference Bottaccione section (central Italy) is characterized by the presence of black shales containing high TOC concentrations (up to 17%) and amounts of CaCO3 near to zero. In the absence of carbonate and, consequently, of relative carbon- and oxygen-isotopic data, the elemental geochemistry revealed to be a very useful tool to obtain information about the palaeoclimatic and palaeoceanographic evolution of the Tethys Ocean during the OAE2. Based on several geochemical proxies (Rb, V, Ni, Cr, Si, Ba), the BL is interpreted as a high-productivity event driven by increasingly warm and humid climatic conditions promoting an a…
Low-energy decay pathways of doubly charged silver clusters $Ag_{n}^{2+}$ (n = 9 - 24)
1997
The low-energy dissociation channels of mass selected silver cluster ions Ag n 2+ (n = 9–24) are determined by collision induced dissociation (CID) in a Penning trap. While all clusters of the size n ≥ 17 evaporate neutral monomers, most smaller clusters undergo asymmetric fission of the form Ag n 2+ → Ag −3 + + Ag {3} + . However, Ag 15 2+ and Ag 11 2+ emit monomers which indicates shell or odd-even effects. The observed fragmentation pathways are different from previous reports of measurements with sputtered Ag n 2+ .
Absolute cross-sections for the nonresonant multi-photon ionization of toluene and xylene in the gas phase
2001
Abstract The absolute multi-photon ionization cross-section of the phenyl ring was determined by laser-ionization of toluene and xylene molecules in the gas phase. Excitation was achieved using nonresonant four-photon absorption of the frequency doubled light of a 10 ns pulsed Nd:YAG laser (532 nm). The resulting ions were stored in a Penning trap and detected by time-of-flight mass spectrometry. The values of the cross-sections are 1.4(3)×10 −42 cm 8 W −4 s −1 and 1.3(3)×10 −42 cm 8 W −4 s −1 for toluene and xylene, respectively.
DELAYED ELECTRON EMISSION OF NEGATIVELY CHARGED TUNGSTEN CLUSTERS
1996
The delayed electron emission of negatively charged tungsten clusters has been investigated on a time scale from 1 to 500 ms. After being stored in a Penning trap clusters ions [Formula: see text] were heated via multiphoton absorption (hν=1.81 eV). In contrast to alkali and coinage metals no photofragmentation could be detected. Instead, for all cluster sizes studied so far only a decrease in the initial ion intensity as a function of time after excitation was observed. This decrease is not caused by ion loss from the trap, but has to be attributed to neutralization via delayed electron emission. The presented results strongly suggest that this process can be viewed as “thermionic emissio…
Extended valence theory perspective on consumers' e-waste recycling intentions in Japan
2021
The gravity of the electronic waste (e-waste) crisis can be attributed to consumers' low participation in ensuring the proper disposal of such materials. Motivating consumers to recycle e-waste requires a deeper understanding of the dimensions that underlie behavioral intentions. Accordingly, the present study uses the novel framework of Valence Theory (VT) to examine how consumers evaluate their decision to recycle e-waste. The authors propose an extended VT model incorporating consumer values (value compatibility, openness to change, and environmental concerns), which is validated using cross-sectional survey data from 774 Japanese consumers. We also examine the role of different moderato…
Il viandante senz'ombra
2018
La formazione letteraria di Sandro Penna
β Decay of 127Cd and Excited States in 127In
2019
A dedicated spectroscopic study of the β decay of 127Cd was conducted at the IGISOL facility at the University of Jyväskylä. Following high-resolution mass separation in a Penning trap, β−γ−γcoincidences were used to considerably extend the decay scheme of 127In. The β-decaying 3/2+ and 11/2− states in 127Cd have been identified with the 127Cd ground state and the 283-keV isomer. Their respective half-lives have been measured to 0.45(128)s and 0.36(4) s. The experimentally observed βfeeding to excited states of 127In and the decay scheme of 127In are discussed in conjunction with large-scale shell-model calculations. peerReviewed
The TRAPSENSOR facility: an open-ring 7 tesla Penning trap for laserbased precision experiments
2019
APenning-trap facility for high-precision mass spectrometry based on a novel detection method has been built. This method consists in measuring motional frequencies of singly-charged ions trapped in strong magnetic fields through the fluorescence photons from laser-cooled 40Ca+ ions, to overcome limitations faced in electronic single-ion detection techniques. The key element of this facility is an open-ring Penning trap coupled upstream to a preparation Penning trap similar to those used at Radioactive Ion Beam facilities. Here we present a full characterization of the trap and demonstrate motional frequency measurements of trapped ions stored by applying external radiofrequency fields in r…
Hieracium hypochoeroides subsp. peracutisquamum (Asteraceae), a new taxon from Basilicata, (southern Italy)
2015
Hieracium hypochoeroides subsp. peracutisquamum, a new taxon endemic to Basilicata (southern Italy), is described and illustrated. It is confined to the carbonate rocks of Monte della Madonna di Viggiano (Lucanian Apennine, SW Basilicata). Information on its ecology and taxonomic relationships is provided.
Język(i) w przestrzeni publicznej w świetle teorii socjologicznej i badań empirycznych. Casus młodzieży Śląska Opolskiego
2020
opennessThe article is devoted to the social dimension of linguistic phenomena occurring in Opole region. The Signum specificum of this region consists of: the dialect as a criterion for delimiting the Silesian group and the German language with the related issue of bilingualism. The aim of the article is to present the scope of research conducted by sociologists from Opole on the subject of the diverse linguistic phenomena occurring in the region. The article GWI2DZstates the theoretical and methodological assumptions of the new project of sociological research on bilingualism and multilingualism in the region, and presents the results of a pilot study conducted in 2019 among high school s…