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Peer Reviewed
See detailOrgano-mineral imprints in fossil cyanobacterial mats of an Antarctic lake
Javaux, Emmanuelle ULg; Lepot, Kevin ULg; Deremiens, Leo et al

Poster (2010, December)

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See detailOrgano-mineral imprints in fossil cyanobacterial mats of an Antarctic lake
Lepot, Kevin ULg; Deremiens; Namsaraev, Zorigto ULg et al

Poster (2011, April 07)

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See detailOrganocatalytic promoted coupling of carbon dioxide with epoxides: a rational investigation of the cocatalytic activity of various hydrogen bond donors
Alves, Margot ULg; Grignard, Bruno ULg; Gennen, Sandro ULg et al

in Catalysis Science & Technology (2015), 5(9), 4636-4643

A catalytic platform based on an onium salt used in combination with organic cocatalysts of various structures was developed for the efficient CO2/epoxide coupling under mild conditions. Through detailed ... [more ▼]

A catalytic platform based on an onium salt used in combination with organic cocatalysts of various structures was developed for the efficient CO2/epoxide coupling under mild conditions. Through detailed kinetic studies by in-situ FT-IR spectroscopy, a rational investigation of the efficiency of a series of commercially available hydrogen bond donors co-catalysts was realized and the influence of different parameters such as the pressure, the temperature, the catalyst loading, and the nature of the epoxide on the reaction kinetics was evaluated. Fluorinated alcohols were found to be more efficient than other hydrogen bond donor activators proposed previously in the literature under similar conditions. [less ▲]

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See detailOrganocatalytic synthesis of bio-based cyclic carbonates from CO2 and vegetable oils
Alves, Margot ULg; Grignard, Bruno ULg; Gennen, Sandro ULg et al

in RSC Advances (2015), 5

Bio-based cyclic carbonates were synthesized by coupling CO2 with epoxidized linseed oil using a catalytic platform composed of a bicomponent organocatalyst. A screening of the catalytic activity of a ... [more ▼]

Bio-based cyclic carbonates were synthesized by coupling CO2 with epoxidized linseed oil using a catalytic platform composed of a bicomponent organocatalyst. A screening of the catalytic activity of a series of organic salts and ionic liquids used in combination with (multi)phenolic or fluorinated hydrogen bond donors was realized before highlighting the synergistic effect between the organocatalyst and the most efficient cocatalysts. These kinetics studies, followed by IR spectroscopy under pressure, enabled to optimize the reaction conditions and to provide quantitative formation of the cyclocarbonated vegetable oil in short reaction time without using any organic solvent. [less ▲]

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See detailOrganocatalyzed ring-opening polymerization of cyclic phosphate monomers
Clement, Benoît ULg; Vanslambrouck, Stéphanie ULg; Koole, Leo H. et al

Conference (2013, November 19)

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See detailOrganocatalyzed synthesis of cyclic carbonates from epoxidized vegetable oils and carbon dioxide
Alves, Margot ULg; Méreau, Raphaël; Grignard, Bruno ULg et al

Conference (2014, March)

The present project relies on the chemical fixation of CO2 and the utilization of vegetable oils as a substitute for basic petroleum derivatives for the production of new monomers and new bio-based ... [more ▼]

The present project relies on the chemical fixation of CO2 and the utilization of vegetable oils as a substitute for basic petroleum derivatives for the production of new monomers and new bio-based organic polymers. In this context, a “greener” approach has been developed to produce bio-sourced polyurethanes by reaction of bio-based cyclic carbonates and amines. Bio-based cyclic carbonates can be synthesised with a total atom economy by chemical fixation of carbon dioxide onto an epoxidized vegetable oil using an appropriate catalyst. However, the conventional catalysts exhibit high catalytic activity only at high temperature and/or pressure or are sensitive to moistures water and/or oxygen. The aim of the present study is to investigate new organocatalytic platforms enabling the cycloaddition of CO2 onto epoxidized oils in the most efficient way under mild conditions. For such task, in situ kinetic follow-up of the cycloaddition of model epoxides and epoxidized oils onto CO2 has been performed by FT-IR spectroscopy in order to to determine the catalytic activity of new binary organocatalytic systems and to evaluate the influence of various parameters (pressure, temperature, catalyst concentration, nature of the epoxide) on the yields and the reaction kinetics. Then, few catalytic systems have been investigated by molecular modeling in order to understand the reaction mechanism. [less ▲]

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See detailOrganochloride pesticides in Macedonian girls with premature sexual development
Krstevska-Konstantinova, M.; Kocova, M.; Charlier, Corinne ULg et al

in Balkan Journal of Medical Genetics [=BJMG] (2007), 10(1), 43-48

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See detailOrganochlorine pesticides, polychlorinated biphenyls and trace elements in wild European sea bass (Dicentrarchus labrax) off European estuaries
Schnitzler, Joseph ULg; Thomé, Jean-Pierre ULg; Lepage, Mario et al

in Science of the Total Environment (2011), 409(19), 3680-3686

Polychlorinated biphenyls (PCBs) and organochlorine pesticides like dichloro-diphenyl-trichloroethane (DDTs), hexachlorocyclohexanes (HCHs), aldrin, dieldrin and trace elements (Cd, Cu, Se, Pb, Zn and Hg ... [more ▼]

Polychlorinated biphenyls (PCBs) and organochlorine pesticides like dichloro-diphenyl-trichloroethane (DDTs), hexachlorocyclohexanes (HCHs), aldrin, dieldrin and trace elements (Cd, Cu, Se, Pb, Zn and Hg) were analysed in the muscle of European sea bass (Dicentrarchus labrax) sampled in Atlantic coastal regions near several important European river mouths (Gironde, Charente, Loire, Seine and Scheldt). High contamination levels were measured in the muscles of European sea bass sampled in the coastal regions near those river mouths (e.g. Σ ICES PCB=133–10,478 μg kg−1 lw and Hg=250–2000 μg kg−1 dw). The Scheldt and the Seine are still among the most contaminated estuaries in Europe. Each region presented their specific contamination patterns reflecting different sources due to the input of the respective rivers. As fish and fishery products are the main contributors of the total dietary intake of organochlorinated pollutants, regular consumption of European sea bass with the reported contamination levels may represent a significant exposure route for the general human population. [less ▲]

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See detailOrganochlorine pollutants in sea turtles and their association with vitamin A
Dyc, Christelle ULg; Debier, Cathy; Thomé, Jean-Pierre ULg et al

Poster (2010, May)

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See detailOrganochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation
Coat, Sophie; Monti, Dominique; Legendre, Pierre et al

in Environmental Pollution (2011), 159

Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the ... [more ▼]

Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a general and heavy contamination of the entire food web. They revealed the strong accumulation of pollutants by juveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in the bioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone and monohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of b-HCH was only influenced by animal lipid content. The biomagnification potential of chlordecone through the food chain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulation process. In contrast, bioconcentration by passive diffusion from water seemed to be the main exposure route of biota to b-HCH. [less ▲]

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See detailOrganochlorines and lactation : mobilization and transfer to offspring in northern elephant seals
Debier, Cathy; Crocker, D.; Xhonneux, V. et al

in Organohalogen Compounds (2007), 69

The transfer of PCBs and DDTs from mother to pup was studied in 20 Northern elephant seal Mirounga angustirostris mother-pup pairs. Organochlorine concentrations in milk increased from 127.3 ± 25.0 ng/g ... [more ▼]

The transfer of PCBs and DDTs from mother to pup was studied in 20 Northern elephant seal Mirounga angustirostris mother-pup pairs. Organochlorine concentrations in milk increased from 127.3 ± 25.0 ng/g to 200.9 ± 39.6 ng/g for PCBs and from 278.2 ± 92.4 ng/g to 494.9 ± 163.4 ng/g for DDTs between day 4 and day 21 of lactation. A similar longitudinal rise was observed in the serum of mothers (5.4 ± 0.8 to 7.7 ± 1.4 ng/ml for PCBs and 7.8 ± 2.4 to 11.9 ± 4.1 ng/ml for DDTs) and, to a lesser extend, in the serum of their pups (5.8 ± 1.4 to 6.1 ± 2.5 ng/ml for PCBs and 8.3 ± 2.5 to 9.9 ± 4.3 ng/ml for DDTs) between early and late lactation. The rise of contaminants in serum and milk might originate from the changes observed in maternal inner blubber in which PCB and DDT levels increased significantly throughout lactation (604.2 ± 142.8 to 1292.5 ± 421.6 ng/g lipids for PCBs and 1223.9 ± 460.0 to 2395.9 ± 737.3 ng/g lipids for DDTs). By contrast, contaminant levels remained constant in outer blubber (933.2 ± 271.8 to 999.7 ± 223.5 ng/g lipids for PCBs and 2010.7 ± 698.3 to 2061.9 ± 603.5 ng/g lipids for DDTs). [less ▲]

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See detailOrganochlorines in harbour porpoises (Phocoena phocoena) stranded along the southern North Sea between 2010 and 2013.
Mahfouz, Celine; Henry, Francoise; Jauniaux, Thierry ULg et al

in Environmental Science. Processes & Impacts (2014), 16(12), 2774-81

7 polychlorinated biphenyls (PCBs), 6 dichlorodiphenyltrichloroethanes (DDXs) and 8 polybrominated diphenyl ethers (PBDEs) were measured in the blubber of 20 harbour porpoises stranded on the coasts of ... [more ▼]

7 polychlorinated biphenyls (PCBs), 6 dichlorodiphenyltrichloroethanes (DDXs) and 8 polybrominated diphenyl ethers (PBDEs) were measured in the blubber of 20 harbour porpoises stranded on the coasts of the southern North Sea between 2010 and 2013. The results showed that porpoises that died from infectious diseases displayed significantly higher levels of PCBs in their blubber compared to healthy porpoises that died from physical trauma. summation operator7CBs and summation operatorDDXs were higher in juvenile porpoises compared to adult females. Except for three individuals, PBDE concentrations were below the limit of quantification in the blubber samples treated. In general, levels of PCBs and DDXs obtained in the blubber of porpoises from this study were in the same order of magnitude or even lower than those obtained in the blubber of porpoises stranded along the North East Atlantic Ocean and the Black Sea over the period 1987 and 2013. The results of the present study suggest that even if the status of marine pollution has been improved, a continuous long-term contamination by toxic organochlorines over many generations may be observed. [less ▲]

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See detailOrganoclays prepared in supercritical CO2: implication of onium stability on the properties of PA6 nanocomposites
Naveau, Elodie ULg; Calberg, Cédric ULg; Detrembleur, Christophe ULg et al

Conference (2009, June 23)

The organomodification of layered silicates via our patented supercritical CO2 ion-exchange process, enables the use of a large variety of surfactants, among which phosphonium and ammonium ions of the ... [more ▼]

The organomodification of layered silicates via our patented supercritical CO2 ion-exchange process, enables the use of a large variety of surfactants, among which phosphonium and ammonium ions of the very same structure. The as-obtained organoclays were melt blended with PA6 and the morphology as well as the fire properties of the nanocomposites were studied. With the same degree of nanodispersion, longer ignition times were observed with phosphonium-modified clays compared to ammonium-modified clays. [less ▲]

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See detailOrganometallic-mediated radical polymerization of vinyl amides: Effect of metal coordination
Kermagoret, Anthony ULg; Morin, A.; Hurtgen, Marie ULg et al

Poster (2012, September 04)

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See detailOrganometallic-mediated radical polymerization of vinyl amides: Effect of metal coordination
Kermagoret, Anthony ULg; Morin, A.; Hurtgen, Marie ULg et al

Conference (2012, September 04)

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See detailOrganometallic-mediated radical polymerization: unusual route toward (quasi-) diblock graft copolymers starting from a mixture of monomers of opposed reactivity
Hurtgen, Marie ULg; Debuigne, Antoine ULg; Fustin, Charles-André et al

in Macromolecules (2011), 44(12), 4623-4631

Graft copolymers have been prepared by one-step organometallic-mediated radical polymerization (OMRP) for the first time. Poly(ethylene glycol) acrylate (PEGA) was copolymerized with vinyl acetate (VAc ... [more ▼]

Graft copolymers have been prepared by one-step organometallic-mediated radical polymerization (OMRP) for the first time. Poly(ethylene glycol) acrylate (PEGA) was copolymerized with vinyl acetate (VAc) to yield well-defined P(PEGA-grad-VAc) gradient graft copolymers using bis(acetylacetonato)cobalt(II) as the control agent. The influence of experimental parameters such as the PEGA/VAc molar ratio, the nature of the initiator, and the temperature on the control of the copolymerization was discussed. The use of an excess of cobalt complex appeared as a key parameter to maintain a good level of control when higher contents of acrylate were used in the comonomer feed. The reactivity ratios were estimated and revealed that PEGA was added around 30 times faster than VAc, which gave access to a gradient P(PEGA-grad-VAc) copolymer or to a P(PEGA-grad-VAc)-b-PVAc diblock copolymer when the VAc polymerization was pursued after the full consumption of PEGA. The amphiphilic character of the copolymers makes them prone to self-assemble into micelles in water, as evidenced by dynamic light scattering. [less ▲]

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See detailOrganometallic-mediated radical synthesis of well-defined ethylene-vinyl acetate statistical and block copolymers
Demarteau, Jérémy ULg; Kermagoret, Anthony; Jérôme, Christine ULg et al

Poster (2015, May 18)

The copolymerization of ethylene (E) and vinyl acetate (VAc) is of high interest for polymer industry. Nevertheless, the control of the macromolecular parameters of ethylene-vinyl acetate copolymers (EVAs ... [more ▼]

The copolymerization of ethylene (E) and vinyl acetate (VAc) is of high interest for polymer industry. Nevertheless, the control of the macromolecular parameters of ethylene-vinyl acetate copolymers (EVAs) is difficult to achieve. Herein, we report the controlled radical copolymerization of these monomers by organometallic-mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent. The ethylene pressure is varied from 10 to 100 bar and we discuss the effect of this parameter on kinetics, level of control and copolymer composition. EVAs are synthetized accordingly with low dispersities and ethylene content reaches up to 57 mol%. The precision design of EVA-containing block copolymers, i.e. PVAc-block-EVA, is also addressed. [less ▲]

Detailed reference viewed: 21 (4 ULg)