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See detailHeavy elements abundances in metal-poor stars
Magain, Pierre ULiege; Jehin, Emmanuel ULiege; Neuforge, Corinne et al

in American Institute of Physics Conference Series (1998, February 01)

A sample of 21 metal-poor stars have been analysed on the basis of high resolution and high signal-to-noise spectra. Correlations between relative abundances of 16 elements have been studied, with a ... [more ▼]

A sample of 21 metal-poor stars have been analysed on the basis of high resolution and high signal-to-noise spectra. Correlations between relative abundances of 16 elements have been studied, with a special emphasis on the neutron-capture ones. This analysis reveals the existence of two sub-populations of field halo stars, namely Pop IIa and Pop IIb. They differ by the behaviour of the s-process elements versus the alpha and r-process elements. We suggest a scenario of formation of these stars, which closely relates the field halo stars to the evolution of globular clusters. The two sub-populations would have evaporated the clusters during two different stages of their chemical evolution. [less ▲]

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See detailHeavy elements in halo stars: the r/s-process controversy.
Magain, Pierre ULiege

in Astronomy and Astrophysics (1995), 297

It has been suggested by Truran (1981) that rapid neutron captures (the r-process) dominate the production of heavy elements in very metal-poor stars. Several spectroscopic works analyzing that hypothesis ... [more ▼]

It has been suggested by Truran (1981) that rapid neutron captures (the r-process) dominate the production of heavy elements in very metal-poor stars. Several spectroscopic works analyzing that hypothesis are reviewed and rediscussed and it is shown that there is, in fact, no secure observational evidence in support of Truran's suggestion. A method to determine the odd-to-even isotopic ratio of barium, and thus to estimate the relative contributions of the r and s-processes, is presented. It takes advantage of the hyperfine structure affecting the spectral lines of the odd isotopes to distinguish them from the even isotopes. This method, applied to the classical metal-poor subgiant HD 140283, shows that the barium isotopic ratio in that star is in agreement with a pure s-process production, and excludes any significant enhancement of the r-process contribution, in disagreement with previous works based on elemental abundances. [less ▲]

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See detailHeavy fermion behavior of U2T2X compounds
Havela, Ladislav; Sechovsky, Vladimir; Svoboda, P. et al

in Journal of Applied Physics (1994), 76(10), 6214-6215

Magnetic and specific-heat studies of U2T2X compounds show a frequent occurrence of the gamma enhancement in conjunction with the onset of antiferromagnetic ordering. The largest value of 830 mJ/mol K**2 ... [more ▼]

Magnetic and specific-heat studies of U2T2X compounds show a frequent occurrence of the gamma enhancement in conjunction with the onset of antiferromagnetic ordering. The largest value of 830 mJ/mol K**2 was observed in U2Pt2In, which is nonmagnetic down to 1.2 K. Variations of electronic structure are documented by optimized relativistic LCAO calculation. [less ▲]

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See detailHeavy fermion behavior of U2T2X compounds
Havela, Ladislav; Sechovsky, Vladimir; Svoboda, P. et al

Poster (1994, August)

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See detailHeavy fermion behavior of U2T2X compounds
Havela, Ladislav; Sechovsky, Vladimir; Svoboda, P. et al

Poster (1994, June)

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See detailHeavy Ion Collisions and Equation of State. An Overview
Cugnon, Joseph ULiege

in La Physique avec Mimas, Quatrièmes journées d'études Saturne (1987)

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See detailHeavy meatal dynamics in the Calvi Bay seagrass bed.
Nélissen, Jean-Pierre; Gobert, Sylvie ULiege; Bouquegneau, Jean-Marie ULiege et al

Conference (1994, January)

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See detailHeavy metal and endocrine disrupter impact on marine mammals
Das, Krishna ULiege; Siebert, Ursula

in Cielikiewicz, Witold; Connolly, Niamh; Ollier, Gilles (Eds.) et al Proceedings of the EurOCEAN 2004. European Conference on Marine Science and Ocean Technology (2007)

Due to their top position in the trophic network, their long life span and their low rate of pollutant elimination, marine mammals can accumulate high levels of chemicals, such as organic compounds and ... [more ▼]

Due to their top position in the trophic network, their long life span and their low rate of pollutant elimination, marine mammals can accumulate high levels of chemicals, such as organic compounds and heavy metals. In the North Sea, high levels of mercury, PCBs, methyl sulfonyl PCBs, perfluorinated organochemicals, DDT and toxaphene have been found in the liver and blubber of the harbour porpoise Phocoena phocoena and the harbour seal Phoca vitulina. Such compounds may affect the immune and the endocrine systems of these species leading to e.g. an increase susceptibility to infectious diseases, cancers, reproductive and other endocrine dysfunctions. [less ▲]

Detailed reference viewed: 64 (6 ULiège)
See detailHeavy metal hypersensitive mutants in Chlamydomonas reinhardtii.
Hanikenne, Marc ULiege

Scientific conference (2002, December 16)

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See detailHeavy Metals Concentration in Adenodolichos rhomboideus (O. Hoffm.) Harms.
Tshibangu, M.; Nsahlai, V.; Kiatoko, M. et al

in International Journal of Current Research in Biosciences and Plant Biology (2014), 1(5), 16-27

A study was carried out in the mining zone, south east of the DRC, characterized by high soil concentrations of Cu, Co, Zn and Pb. This study aimed to (1) evaluate the contamination of leaves of ... [more ▼]

A study was carried out in the mining zone, south east of the DRC, characterized by high soil concentrations of Cu, Co, Zn and Pb. This study aimed to (1) evaluate the contamination of leaves of Adenodolichos rhomboideus by some trace metals (Cu, Co, Zn and Pb) as a function of pH and total concentrations in the soil; and (2) determine the phytoremediation and phytostabilisation potential of this species. Samples of leaves were either washed or left unwashed. Transfer and accumulation of metals were evaluated as a biological concentration factor (BCF), translocation factor (TF) and bio-accumulation coefficient (BAC). Soil pH values varied from 6.2 to 6.5. Soil heavy metals concentrations varied highly. Those in washed leaves minerals concentrations were largely reduced. All soil values differed (p<0.05) except Cu concentration. For unwashed leaves concentrations, sites differed (p<0.05) and Zn concentration differed (p<0.05) between topographies. For washed leaves, only Zn concentration was affected by sites. A. rhomboideus supported soil contaminated with Cu, Co, Zn and Pb; fodder contained potentially toxic Cu concentrations for sheep. It can be used in phytoremediation, in phytostabilisation and in phytoextraction of soil contaminated by Zn, Pb and Co and Zn. [less ▲]

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See detailHeavy Metals Contamination and Body Condition of Wintering Guillemots (Uria Aalge) at the Belgian Coast from 1993 to 1998
Debacker, Virginie ULiege; Jauniaux, Thierry ULiege; Coignoul, Freddy ULiege et al

in Environmental Research (2000), A84(3), 310-317

A sample of 166 common guillemots (Uria aalge) recovered from Belgian beaches during five wintering seasons, from 1993-1994 to 1997-1998, were examined. At necropsy, postmortem examination including body ... [more ▼]

A sample of 166 common guillemots (Uria aalge) recovered from Belgian beaches during five wintering seasons, from 1993-1994 to 1997-1998, were examined. At necropsy, postmortem examination including body mass, fat reserves, presence or not of intestinal contents, eventual status of oiling, and pathological changes (cachexia, acute hemorrhagic gastroenteropathy (GEAH)) was attributed to each individual. Mild to severe cachexia, a pathology characterized by moderate to severe atrophy of the pectoral muscle as well as reduced amounts or absence of subcutaneous and/or abdominal fat, was observed for most specimens (85.8%). Heavy metal analyses (Cu, Zn, Fe, Cd, Ni, Cr, and Pb) of the tissues (typically liver, kidney, and pectoral muscle) were performed, and total lipids were determined (liver and pectoral muscle). The guillemots collected at the Belgian coast exhibited higher Cu and Zn concentrations compared to individuals collected in more preserved areas of the North Sea such as the northern colonies. A general decrease of their total body mass as well as liver, kidney, and pectoral muscle mass was associated to increasing cachexia severity. Moreover, significantly increasing heavy metal levels (Cu and Zn) in the tissues as well as depleted muscle lipid contents were observed parallel to increasing cachexia severity. On the contrary the organs' total metal burden barely correlates to this status. These observations tend to indicate a general redistribution of heavy metals within the organs as a result of prolonged starvation and protein catabolism (cachectic status). Such a redistribution could well be an additional stress to birds already experiencing stressfull conditions (starvation, oiling). [less ▲]

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See detailHeavy metals in marine mammals
Das, Krishna ULiege; Debacker, Virginie ULiege; Pillet, Stéphane et al

in Vos, Joseph G.; Bossart, Gregory D.; Fournier, Michel (Eds.) et al Toxicology of marine mammals (2003)

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See detailHeavy metals resisting gravity in white dwarfs ?
Rauch, T.; Gamrath, S.; Quinet, Pascal ULiege et al

Poster (2016, July)

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See detailHeavy metals resisting gravity in white dwarfs ?
Rauch, T.; Gamrath, S.; Quinet, Pascal ULiege et al

in Astronomical Society of the Pacific Conference Series (2017), 509

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See detailHeavy metals, organochlorines and polycyclic aromatic hydrocarbons in sperm whales stranded in Southern North sea during the 1994/1995 winter,
Hoolsbeek, L.; Joiris, C. R.; Debacker, Virginie ULiege et al

in Marine Pollution Bulletin (1999), 38

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See detailHeavy methane to explain the unexplained recent methane growth ?
Bader, Whitney ULiege; Strong, Kim; Walker, Kaley

Poster (2016, July)

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more ... [more ▼]

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more potent greenhouse gas. Approximately one fifth of the changes in the Earth’s balance energy caused by human-linked greenhouse gases since the beginning of industrialization (~1750) is due to methane. Methane is emitted by both natural sources and human activities. Indeed, methane can be emitted to the atmosphere through coal mining, oil and gas exploitation, rice cultures, domestic ruminant animals, biomass burning, waste management, wetlands, termites, methane hydrates and ocean. In the atmosphere, methane is mainly destroyed by the radical hydroxyl, also called the detergent of the atmosphere, and therefore plays a major role on the oxidizing capacity of the atmosphere. Since the beginning of the industrialization, atmospheric methane concentrations have increased by 260% to reach 1824 pbb in 2013. From the 1980s until the beginning of the 1990s, atmospheric methane was significantly on the rise, then stabilized during 1999-2006 to rise again afterwards. To this day, the source or sink responsible of this latter increase remains unexplained. Through each emission process, heavy molecules of methane (with one additional neutron either on a carbon or on one hydrogen atom) are emitted along methane (12CH4). The main heavy molecules of methane, called isotopologues (13CH4 and CH3D), are respectively ~110 and ~60 000 times less abundant than methane. Despite their small abundances, they give crucial information on the concentration of methane in the atmosphere and its evolution. Indeed, both isotopologues are emitted with specific emission ratio depending on the emission sources. Determining isotopic ratio of atmospheric methane is therefore a unique tracer of its budget. While the non-monotonous trend of methane is subject of an extensive number of studies, to our knowledge, no study of the isotopic ratio of methane derived from ground-based solar observations has been published to date. Measurements of heavy methane from Fourier Transform InfraRed spectra recorded with state of the art spectrometers installed at Eureka [Arctic, Canada] and Toronto [Ontario, Canada] along with analysis of observations collected by a portable instrument [Portable Atmospheric Research Interferometric Spectrometer for the Infrared, PARIS-IR], installed at Eureka will help fill this gap. Indeed, the produced time series, compared with the corresponding satellite observations (ACE-FTS) products will ease data interpretation and contribute to a global view of the question of isotopologues. [less ▲]

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See detailHeavy n-type doping of SiGe for SIMS calibration
Nguyen, Ngoc Duy ULiege

Report (2007)

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See detailHeavy or not ? Analysing drum placements in hard rock music
Pirenne, Christophe ULiege

Conference (2017, June 09)

The aim of this study is to verify—thanks to computer musical analysis—if downbeats and backbeats placements are different when a drummer plays in a hard rock or in a funk style. In other words, does beat ... [more ▼]

The aim of this study is to verify—thanks to computer musical analysis—if downbeats and backbeats placements are different when a drummer plays in a hard rock or in a funk style. In other words, does beat placements contribute to the heaviness of hard rock? In the field of popular music, many authors admit that there are three ways of placing the bass drum and snare drum beats with respect to metronomic time: either an anticipation, a perfect coincidence, or a slight delay. While the repertoires where the notes coincide with the metronomic time are often described as mechanical and a little cold, the anticipated notes would have a more propitious character to the dance and the delayed notes, would produce a music with a heavy character. These impressions were very often mentioned by those working on heavy metal (Waltzer, Brennan), but they have not been scientifically proven to the extent that these variations are counted in milliseconds. Two new IRCAM software, Audiosculpt and OpenMusic, now make it possible to measure very precisely these smallest variations. Thanks to this software, I will analyze the snare and bass drum hits in a few funk and hard rock songs released in 1970: James Brown's Get Up (I Feel Like Being A) Sex Machine and Super Bad (with "Jabo" Starks on drums) (which were already analyzed in Danielsen’s Presence and Pleasure, 2006). These songs will be compared with Black Night by Deep Purple (Ian Paice on drums), Uriah Heep's Gypsy (Alex Napier on drums) and Led Zepplin's Immigrant Song (John Bonham on drums). With this small sample, I will of course not be able to draw conclusions for hard rock as a whole, but if differences appear, it will be necessary to work on metadata to know if delaying the beats is a representative practice or simply a clean playing style for some drummers. [less ▲]

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