Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
See detailPreparation method of (co)oligomer or (co)polymer by in-situ polymerization of monoethylenically unsaturated monomer and oligomer or polymer secondary amine to control molecular weight and molecular structure
Detrembleur, Christophe ULg; Rüdiger, Claus; Meyer, Rolf-Volker

Patent (2004)

PURPOSE: Provided is a method for preparing a (co)oligomer or a (co)polymer having a controlled molecular weight, a controlled molecular weight and a narrow polydispersity at a relatively low temperature ... [more ▼]

PURPOSE: Provided is a method for preparing a (co)oligomer or a (co)polymer having a controlled molecular weight, a controlled molecular weight and a narrow polydispersity at a relatively low temperature and for a short time. CONSTITUTION: The method comprises the steps of mixing at least one monoethylenically unsaturated monomer represented by HR1C=CR2R3, at least one oxidant, at least one polymer or oligomer represented by the formula 1, and optionally a free radical initiator; and heating the mixture at a temperature of 0-220 deg.C, wherein R1, R2 and R3 are independently H, a C1-C20 alkyl group, a C1-C20 cycloalkyl group, a C6-C24 aryl group, a halogen atom, a cyano group, a C1-C20 alkyl ester group, a C1-C20 cycloalkyl ester group, a C1-C20 alkylamide group, a C1-C20 cycloalkylamide group, a C6-C24 aryl ester group or a C6-C24 arylamide group; Y is an organic residue based on the monomer corresponding to HR1C=CR2R3; m is an integer of 1-50; n is an integer of 1-300; I1 is an initiator; and R4 and X are a secondary or tertiary carbon atom and are independently selected from the group consisting of a C1-C18 alkyl group, a C2-C18 alkenyl group, a C2-C18 alkynyl group, a C3-C12 cycloalkyl group, a C3-C12 hetero cycloalkyl group or a C6-C24 aryl group unsubstituted or substituted with NO2, a halogen atom, an amino group, a hydroxyl group, a cyano group, a carboxyl group, a ketone group, a C1-C4 alkoxy group, a C1-C4 alkylthio group or a C1-C4 alkylamino group. [less ▲]

Detailed reference viewed: 34 (2 ULg)
Full Text
Peer Reviewed
See detailUne préparation multimédias à affronter les conflits professeur-élèves en classe
Leclercq, Dieudonné ULg; Rommes, O.; Georges, François ULg et al

in Education-Formation (1998), 36130

Detailed reference viewed: 48 (9 ULg)
Full Text
Peer Reviewed
See detailPreparation of a Macroporous Biodegradable Polylactide Implant for Neuronal Transplantation
Schugens, C.; Grandfils, Christian ULg; Jérôme, Robert ULg et al

in Journal of Biomedical Materials Research (1995), 29(11), 1349-62

This article reports the production of a surgical implant meeting several specific requirements such as biocompatibility, biodegradability, macroporosity, and flexibility. Porosity was controlled by an ... [more ▼]

This article reports the production of a surgical implant meeting several specific requirements such as biocompatibility, biodegradability, macroporosity, and flexibility. Porosity was controlled by an original method consisting of the aggregation of calibrated poly-D,L-lactide microparticles. The size of the interstices between the aggregated microspheres was in a direct relationship to the microsphere diameter. A first approach was based on coating the microspheres with poly(vinyl alcohol) followed by chemically crosslinking the coating layers that were in mutual contact. This method was disregarded because of the acute cytotoxicity of glutaraldehyde used as the crosslinking agent, the absence of macroporosity, and the complete lack of flexibility. A physical technique of aggregation was then tested, which relied on the plasticization of poly-D,L-lactide microspheres with triethylcitrate to the point where microspheres strongly adhered to each other when they were in contact. This method has proved to be straightforward and definitely superior to the chemical approach, particularly with respect to cytotoxicity, control of macroporosity, and flexibility. A polymer support was thus successfully which was biodegradable, macroporous( interconnected pores of 10-100 microns in diameter), and flexible. This potential medical device is presently being used for neuronal transplantation in the central nervous system. [less ▲]

Detailed reference viewed: 25 (5 ULg)
Full Text
See detailPreparation of A Rapeseed Sample With A Certified Content In Total Glucosinolates (CRM 190)
Wathelet, Jean-Paul ULg; Marlier, M.; Severin, M. et al

in Revue Française des Corps Gras (1989), 36(7-8),

The preparatton af one rapeseed with known content tn total glucosinolates (CRM 190) and the steps taken to confirm their homogeneity and stabtlity are described. Details are presented of the ... [more ▼]

The preparatton af one rapeseed with known content tn total glucosinolates (CRM 190) and the steps taken to confirm their homogeneity and stabtlity are described. Details are presented of the collaborative exercice which led to the certification. lndicative values are given for the content of individual glucosinolates, amino acids, and fatty acids. [less ▲]

Detailed reference viewed: 10 (1 ULg)
Full Text
Peer Reviewed
See detailPreparation of BaZrO3 powders by a spray-drying process
Robertz, B.; Boschini, Frédéric ULg; Rulmont, André ULg et al

in Journal of Materials Research (2003), 18(6), 1325-1332

The potential use of barium zirconate for the manufacture of corrosion-resistant substrates emphasizes the need for a simple, inexpensive, and easily scalable process to produce high-quality powders with ... [more ▼]

The potential use of barium zirconate for the manufacture of corrosion-resistant substrates emphasizes the need for a simple, inexpensive, and easily scalable process to produce high-quality powders with well-controlled composition and properties. However, the classical solid-state preparation of barium zirconate leads to an inhomogeneous powder unsuitable for applications in highly corrosive environment. For this paper, the possibility to use the spray-drying technique for the preparation of BaZrO3 powders with a controlled size distribution and morphology was investigated. The influence of the nature and concentration of the precursor solution and the influence of the spray-drying step are discussed on the basis of x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and dilatometric measurements. [less ▲]

Detailed reference viewed: 54 (4 ULg)
Full Text
See detailPreparation of chitosan-based nanofibers with multilayered structure
Croisier, Florence ULg; Duwez, Anne-Sophie ULg; Dijkstra, P. J. et al

Conference (2011, May 12)

Detailed reference viewed: 36 (4 ULg)
Full Text
Peer Reviewed
See detailPreparation of CMI-1 supported H3+xPMo12-xVxO40 for the selective oxidation of propylene
Benadji, S.; Eloy, P.; Léonard, Alexandre ULg et al

in Studies in Surface Science and Catalysis (2010), 175

Catalysts, comprising 30 wt.% of heteropolyacids (HPAs) H 3+xPMo 12-xV xO 40 (x = 0-3) supported on a mesoporous material CMI-1 by dry impregnation were characterized by several techniques. Their ... [more ▼]

Catalysts, comprising 30 wt.% of heteropolyacids (HPAs) H 3+xPMo 12-xV xO 40 (x = 0-3) supported on a mesoporous material CMI-1 by dry impregnation were characterized by several techniques. Their catalytic performances were compared to those of bulk HPAs in the propylene oxidation by molecular oxygen at 350°C. The supported HPAs exhibit higher catalytic activity in propylene oxidation than the bulk ones and favoured the formation of acrolein, acetaldehyde and acetic acid, compared to the mother catalysts which lead only to the formation of COx. The enhanced oxidation catalytic activity of supported systems was attributed to the fine dispersion of H 3+xPMo 12-xVxO 40 species on the CMI-1 mesoporous material via physical adsorption, together with the fact that the structure of both CMI-1 and HPAs remained intact during the impregnation. © 2010 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 21 (0 ULg)
See detailPreparation of cross-linked chitosan-based nanofibers as wound dressing
Aqil, Abdelhafid ULg; Ziani, K.; Tchemtchoua Tateu, Victor ULg et al

Poster (2009, November 18)

Detailed reference viewed: 51 (19 ULg)
See detailPreparation of drug-loaded scaffolds for biomedical applications using supercritical carbon dioxide technology
Champeau, Mathilde; Jérôme, Christine ULg; Tassaing, Thierry

Conference (2012, March 25)

Detailed reference viewed: 9 (1 ULg)
See detailPreparation of drug-loaded scaffolds for biomedical applications using supercritical fluid technology
Champeau, Mathilde; Jérôme, Christine ULg; Tassaing, Thierry

Conference (2013, March 17)

Detailed reference viewed: 10 (3 ULg)
Full Text
Peer Reviewed
See detailPreparation of fire-resistant poly(styrene-co-acrylonitrile) foams using supercritical CO2 technology
Urbanczyk, Laetitia ULg; Bourbigot, Serge; Calberg, Cédric ULg et al

in Journal of Materials Chemistry (2010), 20

This work deals with the preparation and characterization of fire-resistant poly(styrene coacrylonitrile) (SAN) foams containing (organo)clays and/or melamine polyphosphate (MPP) as fire retardants using ... [more ▼]

This work deals with the preparation and characterization of fire-resistant poly(styrene coacrylonitrile) (SAN) foams containing (organo)clays and/or melamine polyphosphate (MPP) as fire retardants using supercritical CO2 as the foaming agent. The additives dispersion was first characterized with X-ray and transmission electron microscopy (TEM) analyses. Their presence clearly affected the cellular morphology, as observed by scanning electron microscopy (SEM). Then, the peak of heat release rate (PHRR) and total heat evolved (THE) were determined with a cone calorimetry test, performed on each foamed sample as a function of the foam density. Incorporation of clay (3 and 5 wt%) in the exfoliated state into the SAN foam clearly led to a significant decrease of PHRR, while intercalated and aggregated clay had a lower effect. Similar results were obtained with 10 and 20 wt% of MPP. The best results were obtained when exfoliated clay and MPP were combined, with a PHRR drop as large as 75%, thanks to the synergistic action of both additives. The magnitude of PHRR drop, related to the fire resistance, was found to be in direct relationship with the cohesiveness of the protective carbonaceous layer formed at the sample surface during combustion. Clay and MPP, when added together, are thus believed to favour the formation of a highly cohesive protective layer able to act as an efficient shield against the flame, despite the fact that the sample is originally composed of ~90% of voids. [less ▲]

Detailed reference viewed: 73 (22 ULg)
Full Text
See detailPreparation of functionalized alkoxyamine initiator and its use
Detrembleur, Christophe ULg; Gross, Thomas; Meyer, Rolf-Volker

Patent (2003)

A one-pot process for the preparation of functional alkoxyamines of the general formula (I), is disclosed. The process entails (1) reacting an oxidizing agent with a sterically hindered secondary amine to ... [more ▼]

A one-pot process for the preparation of functional alkoxyamines of the general formula (I), is disclosed. The process entails (1) reacting an oxidizing agent with a sterically hindered secondary amine to produce an aqueous phase and a nitroxyl radical (2) removing the aqueous phase and adding to the nitroxyl radical one or more vinyl monomer(s) conforming to a formula and a system which produces free radicals. Also disclosed is a process of polymerizing monomers using the functional alkoxyamine. [less ▲]

Detailed reference viewed: 14 (1 ULg)