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See detailMicrodureté de scorie Thomas LD et LD enrichies
Bastin, David ULg

Report (1998)

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See detailMicrodynamics of reverse micelles of ω- and α,ω-metal sulfonato polystyrene in toluene
Vanhoorne, Pierre ULg; Grandjean, Jean ULg; Jérôme, Robert ULg

in Macromolecules (1995), 28(10), 3553-3561

Reverse micelles of omega- and alpha,omega-metal sulfonato polystyrenes in toluene have been investigated by Li-6, Li-7, and pulsed field gradient NMR. Micelles are found to be of a narrow size ... [more ▼]

Reverse micelles of omega- and alpha,omega-metal sulfonato polystyrenes in toluene have been investigated by Li-6, Li-7, and pulsed field gradient NMR. Micelles are found to be of a narrow size distribution and to consist of roughly spherical ionic cores shielded from the solvent by a polystyrene shell. The nature of the ion pair is found to influence significantly the micellar size. The correlation time characteristic of lithium relaxation is faster than the reorientational correlation time of the aggregates, which means that lithium relaxation essentially takes place within the ionic cores. The effective relaxation mechanism is consistent with a fast exchange of lithium ions between different coordination sites within the aggregates. In concentrated solutions, the equilibrium between aggregated polymer chains and unassociated chains is essentially shifted toward the aggregated species. This tendency is reversed upon dilution. Below a critical micellar concentration of ca. 0.01 g/dL, only ''free'' chains persist in solution. Temperature has no significant effect on the position of the aggregation equilibrium. The aggregates are dissociated by the addition of a polar cosolvent, such as methanol, which solvates the ion pairs. The MeOH/Li+ molar ratio must, however, be higher than 100 to perturb significantly the ion pair aggregation. Up to a MeOH/Li+ ratio of 10 000, part of the chains remain aggregated, and the lithium spin-lattice relaxation is dominated by the aggregates. Above a MeOH/Li+ ratio of 10 000, the aggregates are almost completely disrupted. Self-diffusion coefficients of the difunctional chains are not dramatically smaller compared to the monofunctional counterparts, even when solutions of difunctional compounds form a gel. This behavior might be explained by the percolation model applied to the aggregation process, with the pulsed field NMR experiment probing only the selfdiffusion of the clusters in the sol phase of the gel. [less ▲]

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See detailMicroeconometric Evidence of Financing Friction and Innovative Activity
Tiwari, Amaresh Kumar ULg

Conference (2012, August)

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See detailMicroeconomic co-evolution model for financial technical analysis signals
Rotundo, G.; Ausloos, Marcel ULg

in Physica A-Statistical Mechanics and its Applications (2007), 373

Technical analysis (TA) has been used for a long time before the availability of more sophisticated instruments for financial forecasting in order to suggest decisions on the basis of the occurrence of ... [more ▼]

Technical analysis (TA) has been used for a long time before the availability of more sophisticated instruments for financial forecasting in order to suggest decisions on the basis of the occurrence of data patterns. Many mathematical and statistical tools for quantitative analysis of financial markets have experienced a fast and wide growth and have the power for overcoming classical TA methods. This paper aims to give a measure of the reliability of some information used in TA by exploring the probability of their occurrence within a particular microeconomic agent-based model of markets, i.e., the co-evolution Bak-Sneppen model originally invented for describing species population evolutions. After having proved the practical interest of such a model in describing financial index so-called avalanches, in the prebursting bubble time rise, the attention focuses on the occurrence of trend line detection crossing of meaningful barriers, those that give rise to some usual TA strategies. The case of the NASDAQ crash of April 2000 serves as an illustration. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailMicroencapsulation by Coacervation of Poly(lactide-co-glycolide)-II:Encapsulation of a Dispersed Aqueous Phase
Nihant, Nicole; Stassen, S; Grandfils, Christian ULg et al

in polymer International (1993), 32

This paper is related to the phase separation of different copolyesters of lactides and glycolide solutions induced by the addition of silicone oil in order to promote microencapsulation of proteins. This ... [more ▼]

This paper is related to the phase separation of different copolyesters of lactides and glycolide solutions induced by the addition of silicone oil in order to promote microencapsulation of proteins. This coating process can be divided in three successive steps: phase separation of the coating polymer; adsorption of the coacervate droplets around the drugs phase, and microcapsule solidification. This paper focuses on the physico-chemical analysis of the second step. The knowledge of the interfacial tensions between the three liquid phases allows understanding of the microscopic evolution of the phase separation medium. [less ▲]

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See detailMicroencapsulation by Coacervation of Poly(lactide-co-glycolide). III. Characterization of the Final Microspheres
Nihant, Nicole; Stassen, Sophie; Grandfils, Christian ULg et al

in Polymer International (1994), 34

This paper deals with protein microencapsulation by coacervation of poly(lactide-co-glycolide) solutions in CH2Cl2 induced by the addition of silicone oils of various viscosities. This coating technique ... [more ▼]

This paper deals with protein microencapsulation by coacervation of poly(lactide-co-glycolide) solutions in CH2Cl2 induced by the addition of silicone oils of various viscosities. This coating technique proceeds along three steps: phase separation of the coating polyester, adsorption of the coacervate droplets around the protein phase, and hardening of microparticules. Size distribution, surface morphology and internal porosity of the final microspheres clearly depend on the main characteristics of the coacervate, particularly the viscosity, in a direct connection with the CH2Cl2 content. Indeed, the whole porosity (which may be as high as 80%), average pore size and broadness of pore size distribution decrease as the coacervate is more viscous. Hardening of the coacervate droplets is thus so fast that the organic solvent is entrapped within the polymer matrix and predetermines the internal porosity. Finally, size distribution of microspheres is bimodal in a clear relation with the coacervate viscosity. A less viscous coacervate favours smaller microspheres (within the 7-90 µm range), contaminated with a minor population of microparticles below 4 µm. [less ▲]

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See detailMicroencapsulation by coacervation of poly(lactide-co-glycolide). IV. Effect of the processing parameters on coacervation and encapsulation
Nihant, N.; Grandfils, Christian ULg; Jérôme, Robert ULg et al

in Journal of Controlled Release (1995), 35(2-3), 117-125

Attention has been paid to phase separation of poly (lactide-co-glycolide) solutions in CH2Cl2 induced by the addition of a silicone oil in order to promote protein microencapsulation. Since the process ... [more ▼]

Attention has been paid to phase separation of poly (lactide-co-glycolide) solutions in CH2Cl2 induced by the addition of a silicone oil in order to promote protein microencapsulation. Since the process is very fast, the system is anytime out of equilibrium. The effect of the main processing parameters on the microencapsulation process has been analyzed and has highlighted that kinetics of the main encapsulation steps has a great effect on the characteristics of the final microspheres. These results have been discussed on the basis of a physico-chemical study of coacervation reported in previous papers of this series. [less ▲]

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See detailMicroencapsulation by coacervation of poly(lactide-co-glycolide): Physico-chemical characteristics of the phase separation process
Stassen, S; Nihant, Nicole; Martin, Véronique et al

in Polymer (1994), 35(4), 777-785

This paper describes the phase separation of different lactide and glycolide copolyester solutions, induced by the addition of silicone oil in order to promote protein microencapsulation. The phase ... [more ▼]

This paper describes the phase separation of different lactide and glycolide copolyester solutions, induced by the addition of silicone oil in order to promote protein microencapsulation. The phase diagrams of the ternary CH2Cl2-copolyester-silicone oil systems were established in relation to the composition of the copolyester and the viscosity, i.e. the molecular weight, of the silicone oil. The phase-separated systems were characterized in terms of weight, volume, composition and viscosity of the coacervation agent (silicone oil) on the characteristics of the phase-separated system is discussed. [less ▲]

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See detailMicroencapsulation Of Erythromycin And Clarithromycin Using A Spray-Drying Technique
Zgoulli, S.; Grek, V.; Barre, G. et al

in Journal of Microencapsulation (1999), 16(5), 565-71

Previous methods of microencapsulation are unable to process particles smaller than 100 microm without organic solvents or the use of multistep processes. The present study investigates the feasiblity of ... [more ▼]

Previous methods of microencapsulation are unable to process particles smaller than 100 microm without organic solvents or the use of multistep processes. The present study investigates the feasiblity of a one-step spray-drying process to microencapsulate erythromycin and clarithromycin, antibiotics known to have an unpleasant, bitter taste. Mixtures of clarithromycin (5% by weight) or erythromycin (30% by weight) with a biodegradable polymer were prepared and spray-dried under specific conditions of temperature and turbine speed. This process resulted in the microencapsulation of 80% of each drug as determined by high pressure liquid chromatography. Particle size ranged from 1 to 80 microm as determined by electron microscopy. These data show that microencapsulation of macrolides using a spray-drying technique is feasible. Spray-drying microencapsulation might be useful in the formulation of palatable oral suspensions of bitter tasting drugs. [less ▲]

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See detailMicroencapsulation of erythromycin and clarithromycin using a spray-drying technique.
Grek, V.; Zgoulli, S.; Delcour, M. A. et al

Poster (1994, January)

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See detailMicroencapsulation of HIV antigen: Potential application of the spray-drying technique.
Grek, V.; Zgoulli, S.; Goffinet, Gerhard ULg et al

Poster (1993, December)

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See detailMicroencapsulation par atomisation d'une souche de Lactobacillus acidophilus.
Sabri, Ahmed ULg

Master of advanced studies dissertation (1993)

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See detailMicroencapsulation, principes et applications
Grandfils, Christian ULg

Conference (2002, May 16)

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See detailMicroenvironment and cell fate determination in MCF10A is mediated by ionizing radiation, TGF beta and the extracellular matrix
Fernandez-Garcia, Ignacio; Paupert, Jenny ULg; Barcellos-Hoff, Mary-Helen

Poster (2010)

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See detailMicroenvironmental Regulation of Vascular Homeostasis and Leakage
Sounni, Nor Eddine ULg

Conference (2007, May 22)

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See detailMicroenvironments during antigen stimulation
Heinen, Ernst ULg; Bosseloir, A.; Cormann, N. et al

in Molecular biology of B cells developements (1990)

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See detailMicroenvironments for B cell production and stimulation
Heinen, Ernst ULg; Tsunoda, R.

in Immunology Today (1987), 8

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See detailMicroexplant cultures of the cerebellum
Rogister, Bernard ULg; Moonen, Gustave ULg

in Feoroff, Serguei; Richardson, Arleen (Eds.) Protocols for neural cell cultures (2001)

Detailed reference viewed: 6 (3 ULg)