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See detailOrganic C, N, del 13C and del 15N of suspended particulate matter in the Biscay Shelf Break area
Dauby, Patrick ULg; Frankignoulle, Michel; Elskens, Marc

Conference (1995, February)

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See detailOrganic carbon metabolism and carbonate dynamics in a Mediterranean seagrass (Posidonia oceanica) meadow
Barrón, Cristina; Duarte, Carlos M.; Frankignoulle, Michel et al

in Estuaries and Coasts (2006), 29(3), 417-426

in a Posidonia oceanica meadow and unvegetated sediments of Magalluf Bay (Mallorca Island, Spain) to determine gross primary production (GPP), community respiration (R), and net community production (NCP ... [more ▼]

in a Posidonia oceanica meadow and unvegetated sediments of Magalluf Bay (Mallorca Island, Spain) to determine gross primary production (GPP), community respiration (R), and net community production (NCP). From June 2001 to October 2002, we also measured fluxes of dissolved inorganic carbon (DIC) and total alkalinity (TAlk). The yearly integrated metabolic rates based on DO changes show that the P. oceanica communities are net autotrophic while the metabolic rates in the unvegetated benthic communities are nearly balanced. Higher calcium carbonate (CaCO3) cycling, both in terms of production and dissolution, was observed in P. oceanica communities than in unvegetated benthic communities. In the P. oceanica meadow, the annual release of CO2 from net CaCO3 production corresponds to almost half of the CO2 uptake by NCP based on DIC incubations. In unvegetated benthic communities, the annual uptake of CO2 from net CaCO3 dissolution almost fully compensates the CO2 release by NCP based on DIC incubations. CaCO3 dynamics is potentially a major factor in CO2 benthic fluxes in seagrass and carbonate-rich temperate coastal ecosystems. [less ▲]

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See detailOrganic compositions for repeatedly adjustable optical elements and such elements
Jérôme, Christine ULg; Alexandre, Michaël ULg; Jellali, Rachid ULg

Patent (2011)

The invention relates to an organic transparent liquid composition comprising preformed polymeric chains having some photoactive groups per chain that can reversibly couple, being capable in this way to ... [more ▼]

The invention relates to an organic transparent liquid composition comprising preformed polymeric chains having some photoactive groups per chain that can reversibly couple, being capable in this way to form a transparent solid polymer network with a shape that can be repeatedly and reversibly adjusted by at least local irradiation of the network with electromagnetic waves of different wave lengths whereby the liquid composition is cross-linked at at least one wave length L1 on the one hand and is liquid again by cleaving the cross-link nodes by irradiating the material at at least one other wavelength L2 on the other hand in order to repeatedly adjust the optical properties of said composition in its photo-cross linked state. The composition is applicable as a starting material for intraocular lenses and for other lenses and optical elements. [less ▲]

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See detailOrganic farming - A business perspective
Burny, Philippe ULg; Debode, Frédéric

in Bran, Florina; Cesaretti, Gin Paolo; Ioan, Ildiko (Eds.) et al Advanced study school "The emergence of green businesses by the activation of economic competitiveness' innovative potential within the matrix of sustainable development (2013)

Organic farming is more and more considered as a credible alternative to conventional agriculture, being able to solve current problesm, notably with respect to environment, employment and food safety. In ... [more ▼]

Organic farming is more and more considered as a credible alternative to conventional agriculture, being able to solve current problesm, notably with respect to environment, employment and food safety. In the South of Belgium, Wallonia, organic farming represents today a significant part of agriculture. The goal of this paper is to show the growth of organic farming in Wallonia, to examine the present situation and to analyse the public support granted to organic farming, through direct payments but also through a new regional development plan including research, extension, promotion and the definition of quantified targets concerning economic activity and consumption. The results are based on statistical data collection and on a Survey among organic cereals producers, in order to contribute to the assessment of the economic relevance of organic farming. [less ▲]

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See detailOrganic farming in Wallonia : situation and perspectives
Burny, Philippe ULg

Conference (2010)

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See detailOrganic farming in Wallonia : situation and perspectives
Burny, Philippe ULg

in Petrescu-Mag, Ruxandra-Malina; Petrescu, Dacinia Crina; Burny, Philippe (Eds.) Environmental issues in the context of sustainable development (2011)

The paper describes the recent evolution of organic farming in Wallonia. The share of organic farmers in the total number of farms in Wallonia now reaches 5%, which is also the proportion of organic ... [more ▼]

The paper describes the recent evolution of organic farming in Wallonia. The share of organic farmers in the total number of farms in Wallonia now reaches 5%, which is also the proportion of organic agricultural land in the total agricultural area. The financial support of public authorities, through direct payments or services like research, extension, advertisement, is essential for the maintenance or development of the Wallonian organic sector. This support is not granted for the future, but can be expected. [less ▲]

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See detailOrganic Geo- and Cosmochemistry, Topics in Current Chemistry, Vol. 139
Manfroid, Jean ULg

in Ciel et Terre (1988), 104

Not Available

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See detailOrganic matter sources, fluxes and greenhouse gas exchange in the Oubangui River (Congo River basin)
Bouillon, S.; Yambélé, A.; Spencer, R.G.M. et al

in Biogeosciences (2012), 9

The Oubangui is a major tributary of the Congo River, draining an area of 500 000 km2 mainly consisting of wooded savannahs. Here, we report results of a one year long, 2-weekly sampling campaign in ... [more ▼]

The Oubangui is a major tributary of the Congo River, draining an area of 500 000 km2 mainly consisting of wooded savannahs. Here, we report results of a one year long, 2-weekly sampling campaign in Bangui (Central African Republic) since March 2010 for a suite of physicochemical and biogeochemical characteristics, including total suspended matter (TSM), bulk concentration and stable isotope composition of particulate organic carbon (POC and 13CPOC), particulate nitrogen (PN and 15NPN), dissolved organic carbon (DOC and 13CDOC), dissolved inorganic carbon (DIC and 13CDIC), dissolved greenhouse gases (CO2, CH4 and N2O), and dissolved ignin composition. 13C signatures of both POC and DOC showed strong seasonal variations −30.6 to −25.8 ‰, and −31.8 to −27.1 ‰, respectively), but their different timing indicates that the origins of POC and DOC may vary strongly over the hydrograph and are largely ncoupled, differing up to 6‰ in 13C signatures. Dissolved lignin characteristics (carbon- ormalised yields, cinnamyl:vanillyl phenol ratios, and vanillic acid to vanillin ratios) showed arked differences between high and low discharge conditions, consistent with major seasonal ariations in the sources of dissolved organic matter. We observed a strong seasonality in pCO2, ranging between 470 ± 203 ppm for Q<1000m3 s−1 (n = 10) to a maximum of 3750 pm during the first stage of the rising discharge. The low POC/PN ratios, high %POCand low and variable 13CPOC signatures during low flow conditions suggest that the majority of the POC pool during this period consists of in situ produced phytoplankton, consistent with oncurrent pCO2 (partial pressure of CO2) values only slightly above and, occasionally, below atmospheric equilibrium. Water-atmosphere CO2 fluxes estimated using two independent pproaches averaged 105 and 204 gCm−2 yr−1, i.e. more than an order of magnitude lower than current estimates for large tropical rivers globally. Although tropical rivers are often ssumed to show much higher CO2 effluxes compared to temperate systems, we show that in situ production may be high enough to dominate the particulate organic carbon pool, and lower CO2 values to near equilibrium values during low discharge conditions. The total annual flux of TSM, POC, PN, DOC and DIC are 2.33 Tg yr−1, 0.14 TgC yr−1, 0.014 TgNyr−1, 0.70 TgC yr−1, and 0.49 Tg Cyr−1, respectively. While our TSM and POC fluxes are similar to previous stimates for the Oubangui, DOC fluxes were 30% higher and bicarbonate fluxes were 35% ower than previous reports. DIC represented 58% of the total annual C flux, and under the ssumptions that carbonate weathering represents 25% of the DIC flux and that CO2 from espiration drives chemical weathering, this flux is equivalent to 50% of terrestrial-derived riverine C transport. [less ▲]

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See detailOrganic Rankine Cycle Systems: A Techno-Economic Overview
van den Broeck, Martijn; Quoilin, Sylvain ULg; Declaye, Sébastien ULg et al

in Proceedings of EMC 2013 (2013)

The potential of organic Rankine cycle (ORC) technology for waste heat recovery in industry is discussed. This survey includes a market overview, a discussion of the key differences with steam turbine ... [more ▼]

The potential of organic Rankine cycle (ORC) technology for waste heat recovery in industry is discussed. This survey includes a market overview, a discussion of the key differences with steam turbine technology, some main selection issues (components and working fluid) and an outlook on the future of the technology. [less ▲]

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See detailThe Organic Rankine Cycle: Thermodynamics, Applications and Optimization
Quoilin, Sylvain ULg; Lemort, Vincent ULg

in Exergy, Energy system analysis, and Optimization (2011)

New energy conversion technologies are required in order to ensure the production of electricity without generating environmental pollution. Among them, low-grade heat sources or low power heat sources ... [more ▼]

New energy conversion technologies are required in order to ensure the production of electricity without generating environmental pollution. Among them, low-grade heat sources or low power heat sources present an important potential of development. The Organic Rankine Cycle (ORC) is a well known technology since the early 80’s. A large amount of ORC power plants have been built, mainly for geothermal, waste heat recovery and combined heat and power applications. This technology shows a number of advantages over the traditional steam Rankine cycle that make it more profitable for power plants with a limited electrical output power (typically lower than 1 MWe), despite a lower efficiency. The optimization of the ORC is quite different from that of the steam cycle, mainly because of the heat source temperature limitation, and because there is usually no constraint regarding the vapour quality at the end of the expansion. This chapter presents an overview of the current state of the art in the ORC technology and exposes the main target applications. The modelling of such a cycle is described and issues such as fluid selection, optimization or control of the cycle are thoroughly reviewed. [less ▲]

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See detailOrganic Rankine Cycles including fluid selection
Lemort, Vincent ULg; Declaye, Sébastien ULg; Quoilin, Sylvain ULg

in Handbook of Clean Energy Systems (in press)

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ... [more ▼]

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ebullition temperature than that of water. Hence lower temperature heat sources can be exploited such as solar energy, geothermal energy and waste heat recovery from many different processes. During the design phase of an ORC system, the selection of the working fluid must be conducted in parallel with the selection and the sizing of the components (mainly the expansion machine, the pump and the heat exchangers) and with the definition of the cycle architecture. This approach allows taking into consideration all technical constraints. Relevant properties of working fluids that should be considered during their selection are listed. Major characteristics of available displacement and turbo-expander technologies are described. The impact of the pump performance on the overall performance is discussed and strategies to increase the available NPSH are proposed. Finally, improved cycle architectures are introduced. Major applications of ORC systems are described: geothermal power plants, biomass CHP plants, waste heat recovery in industry, waste heat recovery on internal combustion engines and solar power plants. All these applications differ by the nature of the heat source and heat sink, the integration of the ORC with these sources and sinks, and the range of installed capacities. These differences yield specific designs, which are described. Performance achieved by systems in operation or prototypes are presented. [less ▲]

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See detailOrganic selenium providing by selenized fertilisation in grazed grass, grass and maize silage for beef and dairy cows
Cabaraux, Jean-François ULg; Hornick, Jean-Luc ULg; Dotreppe, Olivier ULg et al

in Biodiversity and animal feed. Future challenges for grassland production. Book of abstracts. 22nd General Meeting of the European Grassland Federation (2008)

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See detailOrganic selenium providing by selenized fertilisation in grazed grass, grass and maize silage for beef and dairy cows.
Cabaraux, Jean-François ULg; Hornick, Jean-Luc ULg; Dotreppe, Olivier ULg et al

in Biodiversity and animal feed. Future challenges for grassland production. Proceedings of the 22nd General Meeting of the European Grassland Federation (2008)

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See detailOrganic silicon decreases interleukine-6 but not leukemia inhibitory factor in human osteoblast-like cells in vitro
Franchimont, Nathalie; Franchimont, Paul; Weekers, Laurent ULg et al

Poster (1995)

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See detailOrganic surface coating on Coccolithophores - Emiliania huxleyi: Its determination and implication in the marine carbon cycle
Godoi, R. H. M.; Aerts, K.; Harlay, Jérôme ULg et al

in Microchemical Journal (2009), 91(2), 266-271

Most of the marine precipitation of CaCO3 is due to the biological activities of planktonic and benthic organisms in waters largely oversaturated with respect to calcium carbonates. This saturation state ... [more ▼]

Most of the marine precipitation of CaCO3 is due to the biological activities of planktonic and benthic organisms in waters largely oversaturated with respect to calcium carbonates. This saturation state is expected to decrease as CO2 increases in seawater. A conventional view in oceanography suggests that calcium carbonates organisms are preserved in oversaturated waters and dissolve only below the lysocline. However. it has be postulated that a fraction of the CaCO3 precipitated biogenically could dissolve in oversaturated waters due to the formation of microenvironments in which respired CO2 decreases the saturation state of seawater (Omega) in the vicinity of CaCO3 crystals. In the present study, cells of the coccolithophore Emiliania huxleyi obtained from laboratory cultures and field samples collected in the Gulf of Biscay, were examined using "variable-energy" electron-probe microanalysis. to determine the presence and thickness of their organic coating. In addition, a new approach for transferring micrometer-sized particles from a filter onto transmission electron microscope grids using manipulators was used to investigate individual coccolithophores. The dry thickness of an organic coating over the coccolithophore surface was found to range between 280 and 350 nm. The resemblance of this coating to the carbohydrates produced and released by the cell is discussed as well as their potential for constituting a microenvironment that hosts bacteria. The properties of this organic coating and its role in the preservation/dissolution and export of biogenic carbonates in the water column are one of the major issues of carbonate geochemistry. (C) 2009 Elsevier B.V. All rights reserved. [less ▲]

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See detailOrganic-walled microfossils in 3.2-billion-year-old shallow-marine siliciclastic deposits
Javaux, Emmanuelle ULg; Marshall, Craig P.; Bekker, Andrey

in Nature (2010), doi:10.1038/nature08793(463), 934-938

Although the notion of an early origin and diversification of life on Earth during the Archaean eon has received increasing support in geochemical, sedimentological and palaeontological evidence ... [more ▼]

Although the notion of an early origin and diversification of life on Earth during the Archaean eon has received increasing support in geochemical, sedimentological and palaeontological evidence, ambiguities and controversies persist regarding the biogenicity and syngeneity of the record older than Late Archaean1–3. Nonbiological processes are known to produce morphologies similar to some microfossils4,5, and hydrothermal fluids have the potential to produce abiotic organic compounds with depleted carbon isotope values6, making it difficult to establish unambiguous traces of life. Here we report the discovery of a population of large (up to about 300 mmin diameter) carbonaceous spheroidal microstructures in Mesoarchaean shales and siltstones of the Moodies Group, South Africa, the Earth’s oldest siliciclastic alluvial to tidalestuarine deposits7. These microstructures are interpreted as organic-walled microfossils on the basis of petrographic and geochemical evidence for their endogenicity and syngeneity, their carbonaceous composition, cellular morphology and ultrastructure, occurrence in populations, taphonomic features of soft wall deformation, and the geological context plausible for life, as well as a lack of abiotic explanation falsifying a biological origin. These are the oldest and largest Archaean organic-walled spheroidal microfossils reported so far. Our observations suggest that relatively large microorganisms cohabited with earlier reported benthic microbial mats8 in the photic zone of marginal marine siliciclastic environments 3.2 billion years ago. [less ▲]

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See detailOrganic-walled microfossils in Mesoarchean shallow-water siliciclastic deposits.
Javaux, Emmanuelle ULg; Marshall, Craig; Bekker, Andrey

Conference (2008)

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See detailOrganigramme général des dispositifs expérimentaux
Claustriaux, Jean-Jacques ULg

Learning material (1983)

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See detailOrganisatie van de ziekteverzekering in Europese context : recente ontwikkelingen en vooruitzihten
Matagne, Geoffroy ULg

in Coninckx, Daniël; Eelen, Kristof; Matagne, Geoffroy (Eds.) et al 50 jaar HZIV (2005)

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See detailL'organisation anatomo-fonctionnelle de la sensibilité douloureuse
Delwaide, P. J.; Schoenen, Jean ULg

in La Douleur en Rhumatologie (1987)

Detailed reference viewed: 8 (0 ULg)