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See detailAtolls et récifs du Frasnien du Synclinorium de Dinant (Belgique, France): sédimentologie et implications paléocéanographiques
Boulvain, Frédéric ULg

in Géologie de la France = Geology of France and Surrounding Areas (2006), (1-2), 53-57

The facies architecture, sedimentary dynamics and palaeogeographical evolution were reconstructed for a number of Middle to Late Frasnian buildups developed on a carbonate platform on the south side of ... [more ▼]

The facies architecture, sedimentary dynamics and palaeogeographical evolution were reconstructed for a number of Middle to Late Frasnian buildups developed on a carbonate platform on the south side of the Dinant Synclinorium (Belgium, France). Nine facies were documented in the buildups, each characterized by a specific range of textures and assemblage of organisms. Sedimentological evidence suggests that facies (1) and (2) correspond to iron bacteria-sponge-dominated communities, developing in a quiet aphotic and hypoxic environment. (3) developed between the storm wave base and the fairweather wavebase, in a oligophotic environment. (5), with stromatolitic coatings and thrombolitic bushes developed close to the fairweather wave base. (6) and the fenestral limestone. (7) correspond to an environment with slightly restricted water circulation. (8) developed at subtidal depths in a quiet, lagoonal environment. The main differences between the Middle and Late Frasnian mounds concerns facies architecture and are a consequence of different palaeoceanographic setting. The large flattened Middle Frasnian Arche and Lion buildups show limited vertical differentiation, large-scale progradation features, extensive exportation of material towards off-reef environment and development of inner lagoonal facies. They grew offshore from a well-developed carbonate platform with a healthy carbonate factory. Middle Frasnian sea level fluctuations were relatively mild, and sedimentation was able to counterpart sea-level rise. At the opposite, during Late Frasnian, severe eustatic rises, together with rising oceanic hypoxic conditions were responsible for frequent collapses of the carbonate factory, drowning of the Middle Frasnian carbonate platform and development of buildups with relatively limited lateral extension, high vertical facies differentiation, low potential for material exportation and high content in microaerophilic iron bacteria. [less ▲]

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See detailAtom Transfer Radical Polymerisation (ATRP) and Kharasch addition mediated by titanium-ruthenium bimetallic systems
Richel, Aurore ULg; Delfosse, Sébastien; Demonceau, Albert ULg et al

Poster (2003)

Numerous studies have been directed towards the synthesis of early-late heterobimetallic complexes. Surprisingly, only few reports have been reported about their catalytic behaviour. However, their ... [more ▼]

Numerous studies have been directed towards the synthesis of early-late heterobimetallic complexes. Surprisingly, only few reports have been reported about their catalytic behaviour. However, their potential in homogeneous catalysis is enormous. Indeed, a co-operative work by the two metal centres in the complex may lead to new catalytic systems with unique reactivity. <br /> <br />The Dijon’s team has concentrated their efforts on the synthesis and study of heterobimetallic complexes in which both metal fragments are known for their catalytic activity. Titanocenes are of considerable interest as catalysts for the polymerisation of a-olefins. The catalytic performance of RuCl2(arene) complexes (1) has been demonstrated in different reactions, including olefin metathesis and atom transfer radical polymerisation (ATRP). In attempts to examine such type of catalytic systems, complexation of bent titanocene metallo-ligands by the [RuCl2(p-cymene)]2 dimer is currently investigated. [less ▲]

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See detailAtom transfer radical polymerisation (ATRP) and Kharasch addition mediated by titanium-ruthenium bimetallic systems
Richel, Aurore ULg; Delfosse, Sébastien; Demonceau, Albert ULg et al

Poster (2002, May)

Numerous studies have been directed towards the synthesis of early-Iate heterobimetallic complexes. Surprisingly, only few reports have been reported about their catalytic behaviour. However, their ... [more ▼]

Numerous studies have been directed towards the synthesis of early-Iate heterobimetallic complexes. Surprisingly, only few reports have been reported about their catalytic behaviour. However, their potential in homogeneous catalysis remains fantastic. Indeed, a cooperative work by the two metal centres in the complex would lead to new catalytic systems with unique reactivity. [less ▲]

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See detailAtom transfer radical polymerization of MMA with a macromolecular ligand in a fluorinated solvent and in supercritical carbon dioxide
Grignard, Bruno ULg; Jérôme, Christine ULg; Calberg, Cédric ULg et al

in European Polymer Journal (2008), 44(3), 861-871

Macromolecular fluorinated ligands were prepared according to a three-step strategy that consists of the random copolymerization of heptadecafluorodecyl acrylate and 2-hydroxyethylacrylate, followed by ... [more ▼]

Macromolecular fluorinated ligands were prepared according to a three-step strategy that consists of the random copolymerization of heptadecafluorodecyl acrylate and 2-hydroxyethylacrylate, followed by the esterification of the pendant hydroxyl groups with acryloyl chloride and the Michael-type addition of tetraethyldiethylenetriamine onto the acrylic double bonds of the polymeric chains. These fluorinated macroligands were successfully used in the atom transfer radical polymerization of MMA catalyzed by a copper salt in a fluorinated solvent. The polymerization control was analyzed in relation to the copper salt, the initiator and the molecular weight and composition of the macroligand before being extended to the heterogeneous ATRP of MMA in scCO2. [less ▲]

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See detailAtom-transfer radical polymerization of vinyl monomers mediated by stable ruthenium-carbene complexes.
Demonceau, Albert ULg; Simal, François; Delaude, Lionel ULg et al

in Abstracts of Papers - American Chemical Society, National Meeting (1999), 218(Part 2), 289-

We reported on the exceptional efficacy of new catalytic systems based on well-defined and fully characterized [RuCl2(p-cymene)(PR3)] complexes (p-cymene = 4-isopropyltoluene) to promote the controlled ... [more ▼]

We reported on the exceptional efficacy of new catalytic systems based on well-defined and fully characterized [RuCl2(p-cymene)(PR3)] complexes (p-cymene = 4-isopropyltoluene) to promote the controlled free-radical polymerization of vinyl monomers without cocatalyst activation. It appeared that only phosphines which are both strongly basic and which possess a well-defined steric bulk presented both high catalytic activity and high control of the polymerization process. The most suitable phosphines were triisopropylphosphine and tricyclohexylphosphine (PCy3, Cy = cyclohexyl). Surprisingly, the best catalyst systems for ATRP were also the most active ones for the ring-opening metathesis polymerization (ROMP) of cycloolefins. With this in mind, [RuCl2(=CHPh)(PCy3)2], the Grubbs' ruthenium-carbene complex commonly used for olefin metathesis, was tested and found to be also highly efficient for ATRP. In this paper, we present some studies on the scope and limitations of stable ruthenium-carbene complexes as potential catalysts for the ATRP of vinyl monomers. [less ▲]

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See detailAtomic data and spectral model for Fe III
Bautista, M A; Ballance, C; Quinet, Pascal ULg

in Astrophysical Journal (2010), 718

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See detailAtomic data and the spectrum of the solar photosphere.
Grevesse, Nicolas ULg; Noels-Grötsch, Arlette ULg

in Physica Scripta (1993), 47

Even though the solar photospheric abundances are now on the whole in very good agreement with the meteoritic values, some problems remain which will only be solved with a higher level of accuracy in the ... [more ▼]

Even though the solar photospheric abundances are now on the whole in very good agreement with the meteoritic values, some problems remain which will only be solved with a higher level of accuracy in the atomic data, especially the transition probabilities for faint lines. The authors justify this request for many more very accurate gf-values through a few particularly striking points. [less ▲]

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See detailAtomic data for radioactive elements RaI, RaII, AcI and AcII and application to their detection in HD 101065 and HR 465
Quinet, Pascal ULg; Argante, C.; Fivet, V. et al

in Astronomy and Astrophysics (2007), 474(1), 307-314

Radiative data for transitions of astrophysical interest in radioactive elements Ra I, Ra II, Ac I and Ac II have been computed using a semi- empirical relativistic Hartree- Fock approach including core ... [more ▼]

Radiative data for transitions of astrophysical interest in radioactive elements Ra I, Ra II, Ac I and Ac II have been computed using a semi- empirical relativistic Hartree- Fock approach including core polarization effects. Most of the oscillator strengths reported in the present paper are new. A possible detection of radium ( Ra II) and actinium ( Ac II) in the spectrum of the stars HD 101065 and HR 465 is examined and discussed. [less ▲]

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See detailAtomic data for VUV lines of astrophysical interest in singly ionized rhodium
Quinet, Pascal ULg; Biémont, Emile ULg; Palmeri, P et al

in Journal of Electron Spectroscopy & Related Phenomena (2011), 184

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See detailAtomic data from the IRON Project. XIX. Radiative transition probabilities for forbidden lines in Fe II
Quinet, Pascal ULg; Le Dourneuf, M; Zeippen, C J

in Astronomy and Astrophysics. Supplement Series (1996), 120

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See detailAtomic decay data for modeling K lines of iron peak and light odd-Z elements
Palmeri, P; Quinet, Pascal ULg; Mendoza, C et al

in Astronomy and Astrophysics (2012), 543

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See detailAtomic decay data for modeling the Al K-lines
Palmeri, P; Quinet, Pascal ULg; Mendoza, C et al

in Astronomy and Astrophysics (2011), 525

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See detailAtomic force microscopy investigation of the morphology and the biological activity of protein-modified surfaces for bio- and immunosensors
Cecchet, Francesca; Duwez, Anne-Sophie ULg; Gabriel, Sabine ULg et al

in Analytical Chemistry (2007), 79(17), 6488-6495

With the purpose of developing biosensors, the reliable proof of the biological activity of two new sensor systems was obtained by atomic force microscopy (AFM) in both the imaging and the single-molecule ... [more ▼]

With the purpose of developing biosensors, the reliable proof of the biological activity of two new sensor systems was obtained by atomic force microscopy (AFM) in both the imaging and the single-molecule force spectroscopy modes. Antigens or antibodies of pharmacological interest were grafted onto self-assembled monolayers of thiols on gold, and AFM imaging demonstrated that the grafting process produced homogeneous submonolayers of isolated proteins. The analysis of the morphology of the surfaces at the different functionalization steps allowed evaluating the protein grafting density and showed that the recognition of complementary species present in the surrounding solution occurred. Single-molecule force spectroscopy experiments between the sensing surfaces and AFM probes, onto which the complementary species were grafted, enabled a direct and rapid test of the biological activity of the sensors by investigating the interaction occurring at the level of one single ligand-receptor bond. Ellipsometry and surface plasmon resonance allowed further characterization of the sensor surfaces and confirmed that the biological recognition took place. [less ▲]

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See detailAtomic force microscopy of supported lipid bilayers.
Mingeot-Leclercq, Marie*-Paule; Deleu, Magali ULg; Brasseur, Robert ULg et al

in Nature Protocols (2008), 3(10), 1654-9

Supported lipid bilayers (SLBs) are widely used in biophysical research to investigate the properties of biological membranes and offer exciting prospects in nanobiotechnology. Atomic force microscopy ... [more ▼]

Supported lipid bilayers (SLBs) are widely used in biophysical research to investigate the properties of biological membranes and offer exciting prospects in nanobiotechnology. Atomic force microscopy (AFM) has become a well-established technique for imaging SLBs at nanometer resolution. A unique feature of AFM is its ability to monitor dynamic processes, such as the interaction of bilayers with proteins and drugs. Here, we present protocols for preparing dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DOPC/DPPC) bilayers supported on mica using small unilamellar vesicles and for imaging their nanoscale interaction with the antibiotic azithromycin using AFM. The entire protocol can be completed in 10 h. [less ▲]

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See detailAtomic layer doping of phosphorus and arsenic: experimental and atomistic modeling
Takeuchi, Shotaro; Yang, Lijun; Nguyen, Ngoc Duy ULg et al

Poster (2008)

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See detailAtomic Lifetimes and Transition Probabilities in Boron-like (Na VII) and Beryllium-like (Na VIII) Sodium Ions
Tordoir, Xavier ULg; Biémont, Emile ULg; Garnir, Henri-Pierre ULg et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (1999), 6

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See detailAtomic Lifetimes of n=2 Levels of Boron-like Na
Tordoir, Xavier ULg; Biémont, Emile ULg; Garnir, Henri-Pierre ULg et al

Conference (1998, August)

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See detailAtomic oxygen distribution in the Venus mesosphere from observations of O[SUB]2[/SUB] infrared airglow by VIRTIS-Venus Express
Gérard, Jean-Claude ULg; Saglam, Adem ULg; Piccioni, Giuseppe et al

in Icarus (2009), 199

This VIRTIS instrument on board Venus Express has collected spectrally resolved images of the Venus nightside limb that show the presence of the (0,0) band of the Deltag1-->Sigmag3 infrared atmospheric ... [more ▼]

This VIRTIS instrument on board Venus Express has collected spectrally resolved images of the Venus nightside limb that show the presence of the (0,0) band of the Deltag1-->Sigmag3 infrared atmospheric system of O[SUB]2[/SUB] at 1.27 mum. The emission is produced by three-body recombination of oxygen atoms created by photodissociation of CO[SUB]2[/SUB] on the dayside. It is consistently bright so that emission limb profiles can be extracted from the images. The vertical distribution of O[SUB]2[/SUB](Deltag1) may be derived following Abel inversion of the radiance limb profiles. Assuming photochemical equilibrium, it is combined with the CO[SUB]2[/SUB] vertical distribution to determine the atomic oxygen density. The uncertainties on the O density caused by the Abel inversion reach a few percent at the peak, increasing to about 50% near 120 km. We first analyze a case when the CO[SUB]2[/SUB] density was derived from a stellar occultation observed with the SPICAV spectrometer simultaneously with an image of the O[SUB]2[/SUB] limb airglow. In other cases, an average CO[SUB]2[/SUB] profile deduced from a series of ultraviolet stellar occultations is used to derive the O profile, leading to uncertainties on the O density less than 30%. It is found that the maximum O density is generally located between 94 and 115 km with a mean value of 104 km. It ranges from less than 1×10[SUP][/SUP] to about 5×10[SUP][/SUP] cm[SUP][/SUP] with a global mean of 2.2×10[SUP][/SUP] cm[SUP][/SUP]. These values are in reasonable agreement with the VIRA midnight oxygen profile. The vertical O distribution is generally in good agreement with the oxygen profile calculated with a one-dimensional chemical-diffusive model. No statistical latitudinal dependence of the altitude of the oxygen peak is observed, but the maximum O density tends to decrease with increasing northern latitudes. The latitudinal distribution at a given time exhibits large variations in the O density profile and its vertical structure. The vertical oxygen distribution frequently shows multiple peaks possibly caused by waves or variations in the structure of turbulent transport. It is concluded that the O[SUB]2[/SUB] infrared night airglow is a powerful tool to map the distribution of atomic oxygen in the mesosphere between 90 and 115 km and improve future Venus reference atmosphere models. [less ▲]

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