Search results for "heavy [meson]"

An increased sensitivity of hydrocarbons-degrading bacteria to heavy metals in the presence of diesel oil

2015

The EPPS16 nuclear PDFs

2017

We report on EPPS16 - the first analysis of NLO nuclear PDFs where LHC p-Pb data (Z, W, dijets) have been directly used as a constraint. In comparison to our previous fit EPS09, also data from neutrino-nucleus deeply-inelastic scattering and pion-nucleus Drell-Yan process are now included. Much of the theory framework has also been updated from EPS09, including a consistent treatment of heavy quarks in deeply-inelastic scattering. However, the most notable change is that we no longer assume flavour-blind nuclear modifications for valence and sea quarks. This significantly reduces the theoretical bias. All the analysed data are well reproduced and the analysis thereby supports the validity o…

Hexafluoro complex of rutherfordium in mixed HF/HNO3 solutions

2008

Formation of anionic fluoride-complexes of element 104, rutherfordium, produced in the 248 Cm( 18 O, 5n) 261 Rf reaction was studied by anion-exchange on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF 6 ] 2- , was formed in the studied fluoride ion concentrations of 0.0005-0.013 M. Formation of [RfF 6 ] 2- was significantly different from that of the homologues Zr and Hf, [ZrF 6 ] 2- and [HfF 6 ] 2- ; the evaluated formation constant of [RfF 6 ] 2- is at least one-order of magnitude smaller than those of [ZrF 6 ] 2- and [HfF 6 ] 2- .

Liquid-Phase Chemistry of Superheavy Elements

2013

An overview over the chemical separation and characterization experiments of the four transactinide elements so far studied in liquid phases, rutherfordium (Rf), dubnium (Db), seaborgium (Sg), and hassium (Hs), is presented. Results are discussed in view of the position of these elements in the Periodic Table and of their relation to theoretical predictions. Short introductions on experimental techniques in liquid-phase chemistry, specifically automated rapid chemical separation systems, are also given. Studies of nuclear properties of transactinide nuclei by chemical isolation will be mentioned. Some perspectives for further liquid-phase chemistry on heavier elements are briefly discussed.

Precision Measurement of the First Ionization Potential of Nobelium

2018

One of the most important atomic properties governing an element's chemical behavior is the energy required to remove its least-bound electron, referred to as the first ionization potential. For the heaviest elements, this fundamental quantity is strongly influenced by relativistic effects which lead to unique chemical properties. Laser spectroscopy on an atom-at-a-time scale was developed and applied to probe the optical spectrum of neutral nobelium near the ionization threshold. The first ionization potential of nobelium is determined here with a very high precision from the convergence of measured Rydberg series to be 6.626 21±0.000 05  eV. This work provides a stringent benchmark for st…

Atmospheric Lead Deposition into Guarapina Lagoon, Rio de Janeiro State, Brazil

1988

The rate of anthropogenic mobilization of heavy metals is higher than the natural supply to the sedimentary environments. I n rivers, lakes and various other terrestrial areas, the drastic increase of heavy metals has been accredited to human activity (Tyler 1972). Erlenkeuser et al. (1974) suggest that Cd, Pb, Zn and Cu in the upper sediment sequence of sediment cores collected from Kiel Bight in the Baltic Sea, are the result of fossil fuel use in industries. Such assemblages have been identified in North America by Goldberg et al. (1977, 1979) from both coastal regions. Sediment cores taken from the deepest part of lakes and lagoons have been analysed to study the historical development …

Response of benthic foraminifera to heavy metal contamination in marine sediments (Sicilian coasts, Mediterranean sea)

2011

To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By c…

Electric control of the spin Hall effect by intervalley transitions

2013

Controlling spin-related material properties by electronic means is a key step towards future spintronic technologies. The spin Hall effect (SHE) has become increasingly important for generating, detecting and using spin currents, but its strength-quantified in terms of the SHE angle-is ultimately fixed by the magnitude of the spin-orbit coupling (SOC) present for any given material system. However, if the electrons generating the SHE can be controlled by populating different areas (valleys) of the electronic structure with different SOC characteristic the SHE angle can be tuned directly within a single sample. Here we report the manipulation of the SHE in bulk GaAs at room temperature by m…

Heavy metal remediation technologies in Latvia: possible applications and preliminary case study results / Technologie remediacji obszarów zanieczysz…

2012

Abstract Environmental contamination with heavy metals as a result of anthropogenic activities is not a recent phenomenon. Contaminated sites with heavy metals can be found in functioning as well as abandoned industrial (brownfield) territories, landfills, residential areas with historical contamination, road sides and rarely in polluted sites by natural activities. Pollution data on its amount and concentrations is known from historical studies and monitoring nowadays, but it should be periodically updated for the use of territorial planning or in case of a change of the land use. A special attention should be paid to heavy metal contamination, because in many cases this contamination is m…

Biomonitoring of Atmospheric Aerosol with the use of Apis mellifera and Pleurozium schreberi

2019

Abstract The aim of the carried out research was to assess atmospheric aerosol pollution levels in the area of three apiaries located in the Opole Province and to analyse heavy metals pollution in bee honey and western honey bees. Pleurozium schreberi moss was used in analysing atmospheric aerosol pollution with the active biomonitoring method, whereas heavy metals levels were determined with flame atomic absorption spectrometry method (F-AAS). Relative Accumulation Factors (RAF) were used in determining increases of analytes concentrations in the moss samples. As a result of the carried out study, the following conclusions have been reached: mosses are good bioindicators of environment pol…