Search results for "mass [baryon]"
showing 10 items of 262 documents
Modelling the optical properties of fresh biomass burning aerosol produced in a smoke chamber: results from the EFEU campaign
2007
A better characterisation of the optical properties of biomass burning aerosol as a function of the burning conditions is required in order to quantify their effects on climate and atmospheric chemistry. Controlled laboratory combustion experiments with different fuel types were carried out at the combustion facility of the Max Planck Institute for Chemistry (Mainz, Germany) as part of the "Impact of Vegetation Fires on the Composition and Circulation of the Atmosphere" (EFEU) project. The combustion conditions were monitored with concomitant CO<sub>2</sub> and CO measurements. The mass scattering efficiencies of 8.9&plusmn;0.2 m<sup>2</sup> g<sup>…
A multivariate approach of the factors impacting a small arctic glacier, Austre Lovén-Spitsberg
2015
International audience; Arctic glaciers are good indicators of the ongoing climate change as their dynamics are strongly linked to it. This study is focused on the Austre Lovén glacier, on the Brøgger peninsula in Spitsbergen (Svalbard, 79°N). The aim is to understand how contrasted climate and snow conditions over the course of a year can lead to multiple consequences, sometimes unexpected, on mass balance. In 2014, a negative budget was expected, but data analysis has shown the first positive mass balance in 7 years. The objective here is to (i) identify and qualify the combination of factors affecting an arctic glacier mass balance. Three primary indicators seem to display the greatest i…
Évaluation de l'influence des facteurs climatiques sur le bilan de masse du glacier Austre Loven (Spitsberg, 79°N) par une approche multivariée
2016
Arctic is a region where a quick warming is ongoing. Effects are particularly visible on glaciers of which dynamics is very sensitive to climate change. The goal of this study is to identify and rank the main climatological and nivological factors influencing the mass balance of a small arctic glacier in Svalbard using a statistical approach. To highlight spatial differences, cartography were then used. Results show that positive degree-days play an important role in explaining mass balance contrary to liquid precipitations that had a marginal effect over the studied period (2007-2014). Moreover, years with very different climatic conditions can lead to a similar mass balance.
Towards high-accuracy mass spectrometry of highly charged short-lived ions at ISOLTRAP
2006
Dedicated to H.-J. Kluge on the occasion of his 65th birthday anniversary - Jürgen Kluge Special Issue; Multiply charged ions of stable xenon isotopes from a plasma ion source have been mass-selected by the on-line mass separator ISOLDE/CERN and delivered to the triple-trap mass spectrometer ISOLTRAP. The doubly charged ions that survived the charge-exchange processes during bunching and ion preparation were transferred to a precision Penning trap for mass determination. Mass values were obtained for the isotopes with mass numbers A=126,129,130,136. They are consistent with previous results except for the case of $^{126}Xe$ where a significant deviation from the literature value was found. …
Search for intermediate mass black hole binaries in the first and second observing runs of the Advanced LIGO and Virgo network
2019
Gravitational wave astronomy has been firmly established with the detection of gravitational waves from the merger of ten stellar mass binary black holes and a neutron star binary. This paper reports on the all-sky search for gravitational waves from intermediate mass black hole binaries in the first and second observing runs of the Advanced LIGO and Virgo network. The search uses three independent algorithms: two based on matched filtering of the data with waveform templates of gravitational wave signals from compact binaries, and a third, model-independent algorithm that employs no signal model for the incoming signal. No intermediate mass black hole binary event was detected in this sear…
Precise branching ratios to unbound 12C states from 12N and 12B β-decays
2009
6 pages, 2 tables, 4 figures.--PACS nrs.: 21.45.-v; 23.40.-s; 27.20.+n; 21.60.De.--Printed version published Aug 3, 2009
Sorption of high pressure fluid mixtures into semi-crystalline polymers: investigation of the system carbon dioxide/vinylidenefluoride/poly(vinyliden…
2008
A novel experimental apparatus for measuring gas absorption has been adopted to study sorption of carbon dioxide CO2 and vinylidenefluoride (VDF) in a semi crystalline polymer, namely poly(vinylidenefluoride) (PVDF). The experimental technique allows to calculate simultaneous absorption of different components in the polymer phase, through a gas chromatographic determination of the composition of the fluid phase. To take into account indirectly the polymer swelling, a suitable not-absorbable probe, namely argon, has been added to the fluid phase. Concentrations of molecules absorbed in the polymer phase were simply calculated through mass balance equations written for each component in the …
The influence of weathering processes on labile and stable organic matter in Mediterranean volcanic soils
2008
The relationship and mechanisms among weathering processes, cation fluxes, clay mineralogy, organic matter composition and stability were studied in soils developing on basaltic material in southern Italy (Sicily). The soils were transitions between Phaeozems and Vertisols. Intense losses of the elements Na, Ca and Mg were measured indicating that weathering has occurred over a long period of time. The main weathering processes followed the sequence: amphibole, mica, volcanic glass or if ash was the primary source→smectite→interstratified smectite–kaolinite→kaolinite. Kaolinite formation was strongly related to high Al, Mg and Na losses. The good correlation between oxyhydroxides and kaolin…
The Influence of Biomass Ash on the Migration of Heavy Metals in the Flooded Soil Profile - Model Experiment
2014
Soils that have been exposed to fl ood waters can be heavily polluted by inorganic and organic compounds. They are mainly compounds which appear in dissolved or suspended form fl owing together with heavily laden fl oodwater, as well as compounds created as a result of reactions in the soil profi le, mostly due to anaerobic transformation of organic matter. Heavy metals brought with fl ood waters are absorbed by the soil and also washed out from fl ood sediments by precipitation when the fl ood recedes. This paper presents the results of research on the effects of fertilization with ash from incineration or pyrolysis of biomass on the migration process of heavy metals (Zn, Cu, Cr, Ni, Pb, C…
Validation of Methylmercury Determinations in Aquatic Systems by Alkyl Derivatization Methods for GC Analysis Using ICP-IDMS
2001
Isotope dilution mass spectrometry (IDMS), using an inductively coupled plasma quadrupole mass spectrometer (ICPMS) and a species-specific methylmercury spike was applied to validate the commonly used GC method for methylmercury (MeHg+) determination, which is based on the formation of volatile methylethylmercury by derivatization with NaBEt4. The spike compound, Me201Hg+, was synthesized by reaction of 201Hg-enriched mercury chloride with methylcobalamin. By analyzing different environmental aquatic samples, it was found that in most cases, transformation of MeHg+ into elemental mercury (Hg0) took place. From investigations of synthetic solutions, it could be followed that halide ions are …