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See detailFermentative biohydrogen production in a novel biodisc bioreactor: Principle and Improvement
Beckers, Laurent ULg; Hiligsmann, Serge ULg; Masset, Julien ULg et al

in Bozhou, Li (Ed.) Low Carbon Earth Summit 2011 Proceeding (2011, October 23)

In order to produce hydrogen at high yields and production rates, the biotechnological process needs to be further optimized and efficient bioreactors must be designed. A biodisc bioreactor has been ... [more ▼]

In order to produce hydrogen at high yields and production rates, the biotechnological process needs to be further optimized and efficient bioreactors must be designed. A biodisc bioreactor has been design and investigated to produce biohydrogen from glucose by the Clostridium butyricum CWBI1009 strain at a high yield and production rate. This reactor, working continuously, has an internal volume of 2.3l but a working volume (liquid phase) of 300ml. Firstly, it enhances the hydrogen production rate (by about 3 times more than a completely stirred bioreactor) by partially fixing the bacteria on the porous support and thus increasing the cell concentration in the bioreactor (decoupling of HRT and SRT). Secondly, the rotating biodisc design enables efficient gas transfer (hydrogen and carbon dioxyde) from the liquid phase where it is produced by the bacteria to the headspace. Indeed, this is an important way to increase hydrogen production yields (by about 25% compared to a completely stirred bioreactor) by allowing the bacteria to focus on the metabolites pathways that produce more hydrogen. Other reactors designs have shown such good results by increasing the interfacial surface. [less ▲]

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See detailFermentative hydrogen production by Clostridium butyricum CWBI1009 and Citrobacter freundii CWBI952 in pure and mixed cultures
Beckers, Laurent ULg; Hiligsmann, Serge ULg; Hamilton, Christopher ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14(S2), 541-548

This paper investigates the biohydrogen production by two mesophilic strains, a strict anaerobe (Clostridium butyricum CWBI1009) and a facultative anaerobe (Citrobacter freundii CWBI952). They were ... [more ▼]

This paper investigates the biohydrogen production by two mesophilic strains, a strict anaerobe (Clostridium butyricum CWBI1009) and a facultative anaerobe (Citrobacter freundii CWBI952). They were cultured in pure and mixed cultures in serum bottles with five different carbon sources. The hydrogen yields of pure C. freundii cultures ranged from 0.09 molH2.molhexose-1 (with sucrose) to 0.24 molH2.molhexose-1 (with glucose). Higher yields were obtained by the pure cultures of Cl. butyricum ranging from 0.44 molH2.molhexose-1 (with sucrose) to 0.69 molH2.molhexose-1 (with lactose). This strain also fermented starch whereas C. freundii did not. However, it consumed the other substrates faster and produced hydrogen earlier than Cl. butyricum. This ability has been used to promote the growth conditions of Cl. butyricum in co-culture with C. freundii, since Cl. butyricum is extremely sensitive to the presence of oxygen which strongly inhibits H2 production. This approach could avoid the addition of any expensive reducing agents in the culture media such as L-cysteine since C. freundii consumes the residual oxygen. Thereafter, co-cultures with glucose and starch were investigated: hydrogen yields decreased from 0.53 molH2.molhexose-1 for pure Cl. butyricum cultures to 0.38 molH2.molhexose -1 for mixed culture with glucose but slightly increased with starch (respectively 0.69 and 0.73 molH2.molhexose-1). After 48 h of fermentation, metabolites analysis confirmed with microbial observation, revealed that the cell concentration of C. freundii dramatically decreased or was strongly inhibited by the development of Cl. butyricum. [less ▲]

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See detailFermentative hydrogen production from glucose and starch using pure strains and artificial co-cultures ofClostridium spp.
Masset, Julien; Calusinska, Magdalena ULg; Hamilton, Christopher et al

in Biotechnology for biofuels (2012), 5(1), 35

ABSTRACT: BACKGROUND: Pure bacterial strains give better yields when producing H2 than mixed, natural communities. However the main drawback with the pure cultures is the need to perform the fermentations ... [more ▼]

ABSTRACT: BACKGROUND: Pure bacterial strains give better yields when producing H2 than mixed, natural communities. However the main drawback with the pure cultures is the need to perform the fermentations under sterile conditions. Therefore, H2 production using artificial co-cultures, composed of well characterized strains, is one of the directions currently undertaken in the field of biohydrogen research. RESULTS: Four pure Clostridium cultures, including C. butyricum CWBI1009, C. pasteurianum DSM525, C. beijerinckii DSM1820 and C. felsineum DSM749, and three different co-cultures composed of (1) C. pasteurianum and C. felsineum, (2) C. butyricum and C. felsineum, (3) C. butyricum and C. pasteurianum, were grown in 20 L batch bioreactors. In the first part of the study a strategy composed of three-culture sequences was developed to determine the optimal pH for H2 production (sequence 1); and the H2-producing potential of each pure strain and co-culture, during glucose (sequence 2) and starch (sequence 3) fermentations at the optimal pH. The best H2 yields were obtained for starch fermentations, and the highest yield of 2.91 mol H2/ mol hexose was reported for C. butyricum. By contrast, the biogas production rates were higher for glucose fermentations and the highest value of 1.5 L biogas/ h was observed for the co-culture (1). In general co-cultures produced H2 at higher rates than the pure Clostridium cultures, without negatively affecting the H2 yields. Interestingly, all the Clostridium strains and co-cultures were shown to utilize lactate (present in a starch-containing medium), and C. beijerinckii was able to re-consume formate producing additional H2. In the second part of the study the co-culture (3) was used to produce H2 during 13 days of glucose fermentation in a sequencing batch reactor (SBR). In addition, the species dynamics, as monitored by qPCR (quantitative real-time PCR), showed a stable coexistence of C. pasteurianum and C. butyricum during this fermentation. CONCLUSIONS: The four pure Clostridium strains and the artificial co-cultures tested in this study were shown to efficiently produce H2 using glucose and starch as carbon sources. The artificial co-cultures produced H2 at higher rates than the pure strains, while the H2 yields were only slightly affected. [less ▲]

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See detailFermi motion and quark off-shellness in elastic vector- meson production
Royen, Isabelle; Cudell, Jean-René ULg

in Nuclear Physics B (1999), B545

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See detailFernand De Visscher als Archäologe - die Elefanten aus Alba Fucens
Gerkens, Jean-François ULg

Scientific conference (2013, March 27)

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See detailFernand De Visscher et la Société Internationale d'Histoire des Droits de l'Antiquité
Gerkens, Jean-François ULg

in Revue Historique de Droit Français et Etranger (in press)

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See detailFernand Graindorge. Cris et chuchotements d’un collectionneur
Bawin, Julie ULg

in catalogue de l’exposition "Fernand Graindorge. Mécène et collectionneur" (2009)

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See detailFERNEST & THE THUNDERS _ FROM LOUISIANA TO BELGIUM
Sacré, Robert ULg

in LIVING BLUES (1980), (45-46), 63-64

a) The discovery of zydeco accordeonist FERNEST ARCENEAUX in Lafayette, LA in 1978 b) Review of a concert at De Warande, Turnhout in Belgium , September 1979 with, a.o., HENRY GRAY ( ex-piano player for ... [more ▼]

a) The discovery of zydeco accordeonist FERNEST ARCENEAUX in Lafayette, LA in 1978 b) Review of a concert at De Warande, Turnhout in Belgium , September 1979 with, a.o., HENRY GRAY ( ex-piano player for Howling Wolf in Chicago) [less ▲]

See detailFERNEST ARCENEAUX & the Thunders - Louisiana Blues & zydeco ; LP sleeve notes
Sacré, Robert ULg

Learning material (1980)

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See detailFerney : une période pour les contes
Tilkin, Françoise ULg

Conference (2002, May 25)

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See detailFerrante Palla : un poète à la cour de Parme
Denis, Benoît ULg

in Tangence (1998, May), (57), 87-94

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See detailLa ferritine érythrocytaire
Guillemin, Ch; Revenant, M. C.; Vernet, V. et al

in Annales de Biologie Clinique (1993), 51

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See detailFerro-potassic a-type granites and related rocks in NE Poland and S Lithuania: West of the East European Craton
Skridlaite, Grazina; Wiszniewska, Janina; Duchesne, Jean-Clair ULg

in Precambrian Research (2003), 124(2-4), 305-326

The present study of monzodiorite, quartz monzodiorite, monzonite, quartz syenite, granodiorite, and rapakivi-like granite surrounding the Suwalki, Ketrzyn and Sejny anorthosite, norite and gabbro plutons ... [more ▼]

The present study of monzodiorite, quartz monzodiorite, monzonite, quartz syenite, granodiorite, and rapakivi-like granite surrounding the Suwalki, Ketrzyn and Sejny anorthosite, norite and gabbro plutons or forming separate bodies in northern Poland and southern Lithuania, has resulted in the recognition of a specific suite with AMCG affinity. The bodies belonging to the Mazury and Veisiejai complexes are aligned to E-W trending lineaments in southern Lithuania and northern Poland with a continuation through the Baltic Sea into south-central Sweden in the west and into NW Belarus in the east. The rocks of the suite form a continuous series ranging from 45 to 75% SiO2 with no indication of the classical Daly gap between mafic and felsic rocks. The Mazury and Veisiejai complexes chemically belong to the ferro-potassic alkali-calcic type of rocks and are comparable with the AMCG suite, e.g. in Rogaland, southern Norway. The most acidic varieties of the granitoids approach the classic rapakivi granites in their petrogenetic characteristics, elevated contents of incompatible elements and REE, and hence have A-type affinities. The granitoids are assigned to the 'Post-collisional Granite' field. The overall evolution from mafic to acidic rocks is characterized by well-defined trends which most probably represent a liquid line of descent. Fractional crystallization with or without assimilation and hybridization can account for the continuous evolution from mafic to acidic members. The formation of the suite is concentrated in the timespan covering almost 50 Myr from 1.55 to 1.5 Ga. The most felsic rocks yield ages of ca. 1.5 Ga, which are very similar to the Kabehai granites further east in southeastern Lithuania. Cooling and local mylonitization proceeded until 1.4 Ga (hornblende and biotite Ar-40/Ar-39 ages). The Mazury and Veisiejai complexes are new evidence that anorthosites and related rocks can be linked to large lithospheric discontinuities. A thick crust and a Moho offset on the recent EUROBRIDGE geophysical profiles could indicate that a slab of lower crustal rock has been melted under the Suwalki massif to produce the AMCG rocks. Recent structural and kinematic observations indicate predominating transpressional/compressional regimes. (C) 2003 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailFerroelectricity and tetragonality in ultrathin PbTiO3 films
Lichtensteiger, C.; Triscone, J. M.; Junquera, J. et al

in Physical Review Letters (2005), 94

The evolution of tetragonality with thickness has been probed in epitaxial c-axis oriented PbTiO3 films with thicknesses ranging from 500 down to 24 Angstrom. High resolution x ray pointed out a ... [more ▼]

The evolution of tetragonality with thickness has been probed in epitaxial c-axis oriented PbTiO3 films with thicknesses ranging from 500 down to 24 Angstrom. High resolution x ray pointed out a systematic decrease of the c-axis lattice parameter with decreasing film thickness below 200 Angstrom. Using a first-principles model Hamiltonian approach, the decrease in tetragonality is related to a reduction of the polarization attributed to the presence of a residual unscreened depolarizing field. It is shown that films below 50 Angstrom display a significantly reduced polarization but still remain ferroelectric. [less ▲]

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See detailFerroelectricity in PbTiO3 thin films: A first principles approach
Rabe, K. M.; Ghosez, Philippe ULg

in Journal of Electroceramics (2000), 4(2-3), 379-383

The ground-state ferroelectric distortion of PbTiO3 thin films is studied using a first-principles effective Hamiltonian to describe the structural energetics at a microscopic level. Under short-circuit ... [more ▼]

The ground-state ferroelectric distortion of PbTiO3 thin films is studied using a first-principles effective Hamiltonian to describe the structural energetics at a microscopic level. Under short-circuit electrical and zero-stress mechanical boundary conditions, (0 0 1) films as thin as one unit cell are found to support a stable perpendicular polarization. Size effects in the layer-by-layer ferroelectric distortion are discussed. The continuum limit of the first-principles effective Hamiltonian has the same form as the widely-used Landau-Ginzburg expression for the free energy near T-c, so that the present results can be directly related to those of previous phenomenological studies. In particular, a microscopic interpretation of the extrapolation length delta is proposed. [less ▲]

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