Search results for "trap"
showing 10 items of 2144 documents
High-accuracy mass measurements on neutron deficient neon isotopes
2005
International audience; The atomic masses of the short-lived nuclides 17Ne and 19Ne have been measured with the triple-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The obtained mass excess for both nuclides deviates significantly from the literature value, in the case of 17Ne about 40 keV. The mass value of 17Ne can be applied for a test of the isobaric multiplet mass equation with respect to an isospin T = 3/2 quartet. In addition, both masses can contribute to the data analysis of collinear laser-spectroscopy experiments where mean-square nuclear-charge radii are determined.
Breakdown of the Isobaric Multiplet Mass Equation atA=33,T=3/2
2001
Mass measurements on ${}^{33,34,42,43}\mathrm{Ar}$ were performed using the Penning trap mass spectrometer ISOLTRAP and a newly constructed linear Paul trap. This arrangement allowed us, for the first time, to extend Penning trap mass measurements to nuclides with half-lives below one second ( ${}^{33}\mathrm{Ar}$: ${T}_{1/2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}174\mathrm{ms}$). A mass accuracy of about ${10}^{\ensuremath{-}7}$ $(\ensuremath{\delta}m\ensuremath{\approx}4\mathrm{keV})$ was achieved for all investigated nuclides. The isobaric multiplet mass equation was checked for the $A\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}33$, $T\phantom{\rule{0ex}{0ex}}=\phantom…
Precision Measurements of Atomic Masses Using Highly Charged Ions and Atomic Clusters
1992
A high precision Penning trap will be connected to the beam of highly charged ions from the electron beam ion source CRYSIS at the Manne Siegbahn Institute for Physics (MSI) in Stockholm. The first series of experiments aim at accurate mass measurements by exploiting the increase of the cyclotron frequency with the charge state of the trapped ion. Using charged states of about 50 it should be possible to achieve relative mass accuracies for mass doublets better than 10-9. For this high accuracy a Penning trap with low imperfections is needed, as well as a sophisticated beam handling and retardation system for controlled injection of the ions into the trap. In order to minimize the effect of…
Detection of changes in mitochondrial hydrogen sulfide i n vivo in the fish model Poecilia mexicana (Poeciliidae)
2019
ABSTRACT In this paper, we outline the use of a mitochondria-targeted ratiometric mass spectrometry probe, MitoA, to detect in vivo changes in mitochondrial hydrogen sulfide (H2S) in Poecilia mexicana (family Poeciliidae). MitoA is introduced via intraperitoneal injection into the animal and is taken up by mitochondria, where it reacts with H2S to form the product MitoN. The MitoN/MitoA ratio can be used to assess relative changes in the amounts of mitochondrial H2S produced over time. We describe the use of MitoA in the fish species P. mexicana to illustrate the steps for adopting the use of MitoA in a new organism, including extraction and purification of MitoA and MitoN from tissues foll…
Maestri e cantieri nella Sicilia interna tra XV e XVI secolo: le chiese Madri di Pietraperzia e Assoro
2014
The essay focuses on two yards of the interior of Sicily between the end of the fifteenth century and the first half of the sixteenth century: the mother church of Pietraperzia and that of Assoro. New documentary investigations allowed to set out the master builders involved in the construction process and to deduce some construction methods in use for churches basilica. These data, together with the direct observation of the buildings have allowed to hypothesize, in both cases, the original configuration of the churches. The hypotheses were supported by a comparison with contemporary building, similar to typological characteristics, and a re-reading of the archival documents referring to t…
Charge injection and trapping at perovskite interfaces with organic hole transporting materials of different ionization energies
2019
The extraction of photogenerated holes from CH3NH3PbI3 is crucial in perovskite solar cells. Understanding the main parameters that influence this process is essential to design materials and devices with improved efficiency. A series of vacuum deposited hole transporting materials (HTMs) of different ionization energies, used in efficient photovoltaic devices, are studied here by means of femtosecond transient absorption spectroscopy. We find that ultrafast charge injection from the perovskite into the different HTMs (<100 fs) competes with carrier thermalization and occurs independently of their ionization energy. Our results prove that injection takes place from hot states in the valence…
Diarylethenes in Optically Switchable Organic Light-Emitting Diodes: Direct Investigation of the Reversible Charge Carrier Trapping Process
2021
Advanced optical materials 10, (2021). doi:10.1002/adom.202101116
A single-atom heat engine
2015
Making a teeny tiny engine Steam locomotives, cars, and the drinking bird toy all convert heat into useful work as it cycles between two reservoirs at different temperatures. Usually, the working substance where the heat-work conversion occurs is a liquid or a gas, consisting of many molecules. Roβnagel et al. have made a working substance of a single calcium ion in a tapered ion trap. A laser-cooling beam plays the part of a cold reservoir for the calcium ion, and in turn, electric field noise acts as a hot reservoir. Science , this issue p. 325
Suppression of electron trapping by quantum dot emitters using a grafted polystyrene shell
2019
A fundamental problem of adding chromophores to an organic host is that their smaller band gap leads to severe trapping of either electrons or holes, resulting in strongly unbalanced transport. We demonstrate that electron trapping by an inorganic quantum dot (QD) in a conjugated polymer host can be suppressed by functionalizing its shell with a thin insulating polystyrene layer. The polystyrene shell not only reduces trapping, but also suppresses detrapping of captured electrons, resulting in increased charging of the QDs with subsequent voltage scans, after initial charging, a red-emitting hybrid polymer:QD light-emitting diode is obtained with voltage independent electroluminescence spec…
Detection and monitoring of carbon monoxide using cobalt corroles film on Love wave devices with delay line configuration
2011
Among specific sensitive materials synthesized for chemical sensor development, cobalt corrole have shown attractive capabilities for CO detection [1, 2]. In this paper, we investigate the possibility to exploit such materials to develop surface acoustic wave (SAW)-based sensors. We actually demonstrate that SAW devices using delay line configuration allow investigating the molecular recognition occurring in non-conductive sensing layers of cobalt corroles. We have monitored phase variations of SAW devices versus various CO concentrations. Moreover, a specific testing setup has been developed to precisely dose CO at low concentrations, to avoid any CO leakage in the environment, to systemat…