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See detailControlled full adder or subtractor by vibrational quantum computing
Bomble, L.; Lauvergnat, D.; Remacle, Françoise ULg et al

in Physical Review. A (2009), 80(2),

A controlled full addition or subtraction can be realized by a unitary transformation on a register of four qubits. The fourth qubit is then used as a control qubit to enforce the addition or the ... [more ▼]

A controlled full addition or subtraction can be realized by a unitary transformation on a register of four qubits. The fourth qubit is then used as a control qubit to enforce the addition or the subtraction of two binary digits and a carry or a borrow. The transformation can be decomposed into six elementary gates. The network differs from the adder network of four elementary gates by including two new controlled-NOT gates. The scheme is general and its implementation using vibrational computing has the advantage that the single global transformation that connects the inputs to the outputs can be driven in one step by a single laser shot. This decreases the time of operation and allows for a better use of the optical resources and for an improvement of the fidelity. The laser pulses are optimized by optimal control theory. [less ▲]

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See detailControlled full adder-subtractor by vibrational computing
Bomble, L.; Lauvergnat, D.; Remacle, Françoise ULg et al

in Physical Chemistry Chemical Physics [=PCCP] (2010), 12(48), 15628-15635

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See detailControlled Memory Processes in Questionable Alzheimer's Disease: A View from Neuroimaging Research
Bastin, Christine ULg; Kerrouche N; Lekeu, Françoise ULg et al

in Journal of Alzheimer's Disease [=JAD] (2010), 20(2), 547-560

Alzheimer's disease (AD) is characterized by a progressive loss of controlled cognitive processes, and neuroimaging studies at early stages of AD provide an opportunity to tease out the neural correlates ... [more ▼]

Alzheimer's disease (AD) is characterized by a progressive loss of controlled cognitive processes, and neuroimaging studies at early stages of AD provide an opportunity to tease out the neural correlates of controlled processes. Accordingly, controlled and automatic memory performance was assessed with the Process Dissociation Procedure in 50 patients diagnosed with questionable Alzheimer's disease (QAD). The patients' brain glucose metabolism was measured using FDG-PET. After a follow-up period of 36 months, 27 patients had converted to AD, while 23 remained stable. Both groups showed a similar decrease in controlled memory processes but preserved automatic processes at entry into the study. Voxel-based cognitive and metabolic correlations showed that a decrease in controlled memory processes was preferentially correlated with lower activity in the dorsomedial prefrontal and posterior cingulate cortices in very early AD patients. In stable QAD patients, reduced controlled performance in verbal memory correlated with impaired activity in the left anterior hippocampal structure. The results demonstrated the central role of a medial frontal-posterior cingulate network for controlled processing of episodic memory in the early stages of AD. [less ▲]

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See detailControlled nitroxide-mediated radical polymerization of styrene, styrene/acrylonitrile mixtures, and dienes using a nitrone
Detrembleur, Christophe ULg; Sciannamea, Valérie; Koulic, Christian et al

in Macromolecules (2002), 35(19), 7214-7223

Radical polymerization of styrene and copolymerization of styrene and acrylonitrile (60/40) are controlled when conducted in the presence of N-tert-butyl-alpha-isopropylnitrone, which is easily ... [more ▼]

Radical polymerization of styrene and copolymerization of styrene and acrylonitrile (60/40) are controlled when conducted in the presence of N-tert-butyl-alpha-isopropylnitrone, which is easily synthesized from cheap reagents. However, for the control to be effective, the nitrone has to be prereacted with the radical initiator. Nitroxides are then formed "in situ", such that this nitrone system is an attractive alternative for the classical nitroxide-mediated polymerization (NMP), which may require a multistep synthesis of nitroxides or alkoxyamines. The choice of the radical initiator is important because it dictates the structure of the nitroxide and thus its capacity to control the radical polymerization. Well-defined poly(styrene)-b-poly(styrene-co-acrylonitrile), poly(styrene)-b-poly(n-butyl acrylate), and poly(styrene)-b-poly(isoprene) copolymers have been successfully synthesized by this process. [less ▲]

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See detailControlled processes account for age-related decrease in episodic memory
Vanderaspoilden, Valérie; Adam, Stéphane ULg; Van der Linden, Martial ULg et al

in Acta Psychologica (2007), 125(1), 20-36

A decrease in controlled processes has been proposed to be responsible for age-related episodic memory decline. We used the Process Dissociation Procedure, a method that attempts to estimate the ... [more ▼]

A decrease in controlled processes has been proposed to be responsible for age-related episodic memory decline. We used the Process Dissociation Procedure, a method that attempts to estimate the contribution of controlled and automatic processes to cognitive performance, and entered both estimates in regression analyses. Results indicate that only controlled processes explained a great part of the age-related variance in a word recall task, especially when little environmental support was offered. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailControlled Production of Exopolysaccharides from Enterobacter A47 as a Function of Carbon Source w ith Demonstration of Their Film and Emulsifying Abilities
Freitas, F; Alves, V.D.; Gouveia, A.R. et al

in Applied Biochemistry and Biotechnology (2013)

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See detailControlled radical (co)polymerization of vinyl monomers using nitrones as precursors of nitroxides
Sciannamea, Valérie; Detrembleur, Christophe ULg; Catala, Jean-Marie et al

Conference (2004, May 27)

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See detailControlled Radical Polymerisation catalysed by rutehnium complexes. Variations on Ru-Cp#
Demonceau, Albert ULg; Delfosse, Sébastien; Guillaume, Bernard et al

in ACS Symposium Series (2002, August)

series of isoelectronic ruthenium-based complexes of the general formula [RuX(Cp#)L2] (Cp# = cyclopentadienyl or cyclopentadienyl derivatives) were synthesized, and their relative catalytic activities ... [more ▼]

series of isoelectronic ruthenium-based complexes of the general formula [RuX(Cp#)L2] (Cp# = cyclopentadienyl or cyclopentadienyl derivatives) were synthesized, and their relative catalytic activities were determined by monitoring the atom transfer radical polymerization of methyl methacrylate, n-butyl acrylate, and styrene. [RuCl(Cp*)(PPh3)2] and [RuCl(Ind)(PPh3)2] were found to be highly efficient catalysts for ATRP, producing polymers with narrow molecular weight distribution (Mw/Mn < 1.2). the following order of increasing efficiency was determined: [RuCl(Cp)(PPh3)2] << [RuCl(ind)(PPh3)2] < [RuCl(Cp*)(PPh3)2]. In sharp contrast, ruthena-carboranes were inefficient for ATRP, demonstrating therefore the prominent role of the Cp# ligand. The effect of the phosphine ligands was also investigated, and additional studies indicated that the release of a phosphine ligand occured prior to the activation of the carbon-halogen bond of both the initiator and polymer growing chain end by the unsaturated ruthenium center. [less ▲]

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See detailControlled radical polymerisation catalysed by ruthenium complexes: Variations on Ru-Cp#
Delfosse, Sébastien; Guillaume, Bernard; Richel, Aurore ULg et al

in Polymer Preprints (2002)

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See detailControlled radical polymerisation of vinyl monomers catalysed by ruthenium N-heterocyclic carbene complexes
Delfosse, Sebastien; Richel, Aurore ULg; Borguet, Yannick ULg et al

in Matyjaszewski, Krzysztof (Ed.) Controlled/living radical polymerization. From synthesis to materials (2005)

N-heterocyclic carbene (NHC)-modified ruthenium catalysts of type [RuCl2(p-cymene)(NHC)] (NHC = substituted 2,3-dihydro-1H-imidazol-2-ylidenes: 1,3-Mes2-4,5-Me2, 1,3-Mes2-4,5-H2, 1,3-Mes2-4,5-Cl2, 1,3-Cy2 ... [more ▼]

N-heterocyclic carbene (NHC)-modified ruthenium catalysts of type [RuCl2(p-cymene)(NHC)] (NHC = substituted 2,3-dihydro-1H-imidazol-2-ylidenes: 1,3-Mes2-4,5-Me2, 1,3-Mes2-4,5-H2, 1,3-Mes2-4,5-Cl2, 1,3-Cy2-4,5-Me2, and 1,3-Cy2-4,5-H2; Mes = mesityl, Cy = cyclohexyl) were prepd. beforehand or in situ by combining the [RuCl2(p-cymene)] dimer with the imidazolium salt in presence of a base (e.g., t-BuOK, Cs2CO3, or Al(OiPr)3). The catalysts were then used in homogeneous atom transfer radical polymns. of Me methacrylate and styrene. The polymn. outcome was studied in dependence of catalyst (substitution pattern) and base. [less ▲]

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See detailControlled radical polymerization catalysed by ruthenium complexes: Variations on Ru-Cp#
Delfosse, Sébastien; Richel, Aurore ULg; Simal, Francois et al

in Matyjaszewski, K. (Ed.) Advances in Controlled/Living Radical Polymerization / ACS Symposium Series 854 (2003)

A series of isoelectronic ruthenium-based complexes of the general formula [RuX(Cp#)L2] (Cp# = cyclopentadienyl or cyclopentadienyl derivatives) were synthesized, and their relative catalytic activities ... [more ▼]

A series of isoelectronic ruthenium-based complexes of the general formula [RuX(Cp#)L2] (Cp# = cyclopentadienyl or cyclopentadienyl derivatives) were synthesized, and their relative catalytic activities were determined by monitoring the atom transfer radical polymerization of methyl methacrylate, n-butyl acrylate, and styrene. [RuCl(Cp*)(PPh3)2] and [RuCl(Ind)(PPh3)2] were found to be highly efficient catalysts for ATRP, producing polymers with narrow molecular weight distribution (Mw/Mn < 1.2). the following order of increasing efficiency was determined: [RuCl(Cp)(PPh3)2] << [RuCl(ind)(PPh3)2] < [RuCl(Cp*)(PPh3)2]. In sharp contrast, ruthena-carboranes were inefficient for ATRP, demonstrating therefore the prominent role of the Cp# ligand. The effect of the phosphine ligands was also investigated, and additional studies indicated that the release of a phosphine ligand occured prior to the activation of the carbon-halogen bond of both the initiator and polymer growing chain end by the unsaturated ruthenium center. [less ▲]

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See detailControlled radical polymerization catalyzed by ruthenium complexes: Variations on Ru-Cp#
Delfosse, Sébastien; Richel, Aurore ULg; Simal, François et al

in Matyjaszewski, Krzysztof (Ed.) ADVANCES IN CONTROLLED/LIVING RADICAL POLYMERIZATION (2003)

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See detailControlled radical polymerization of (meth)acrylates by ATRP with NiBr2(PPh3)2 as catalyst
Moineau, Georges; Minet, Michaël; Dubois, Philippe ULg et al

in Macromolecules (1999), 32(1), 27-35

NiBr2(PPh3)2 has been found to be an efficient catalyst for the ATRP of methyl methacrylate (MMA) and n-butyl acrylate (n-BuA) initiated by an alkyl halide in the absence of any activator (e.g., Lewis ... [more ▼]

NiBr2(PPh3)2 has been found to be an efficient catalyst for the ATRP of methyl methacrylate (MMA) and n-butyl acrylate (n-BuA) initiated by an alkyl halide in the absence of any activator (e.g., Lewis acid) at 85 °C. The molecular weight distribution of the poly(meth)acrylates is narrow (Mw/Mn = 1.1−1.4). However, some side reactions (more likely coupling reactions) are observed at high monomer conversions in the case of n-BuA. An excess of PPh3 has proved to increase the polymerization rate of MMA while preserving the control of the molecular parameters. When the catalyst/initiator molar ratio is too small (e.g., 0.05), the polymerization rate decreases, the polydispersity increases, and the initiation is less efficient. α-Acid and α-hydroxyl end groups have been successfully attached to the chains by using functional initiators, such as 2-bromo-2-methylpropionic acid and 2,2‘,2‘ ‘-tribromoethanol. Reactivity ratios for the MMA/n-BuA comonomer pair have been measured and found to be close to the values observed for a conventional free-radical polymerization. Diethyl meso-2,5-dibromoadipate has been used as a difunctional initiator for the n-BuA polymerization, leading to α,ω-bromo-poly(n-BuA) of narrow molecular weight distribution. Finally, the thermal stability of PMMA is consistent with the lack of termination reactions, while Tg is as high as 125 °C. [less ▲]

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See detailControlled radical polymerization of alkyl methacrylates in the presence of NO/NO2 mixtures
Detrembleur, Christophe ULg; Claes, Michaël; Jérôme, Robert ULg

in Matyjaszewski, Krzysztof (Ed.) Advances in controlled/living radical polymerization (2003)

Radical polymerization of alkyl methacrylates initiated by AIBN is controlled when conducted in the presence of a mixture of NO/NO2. Reaction of alkyl methacrylates with NO/NO2 leads indeed to the monomer ... [more ▼]

Radical polymerization of alkyl methacrylates initiated by AIBN is controlled when conducted in the presence of a mixture of NO/NO2. Reaction of alkyl methacrylates with NO/NO2 leads indeed to the monomer adduct and parent α-nitro, ω-nitroso oligomers, which are precursors of nitroxides, known to control the radical polymerization of alkyl methacrylates, according to a "Nitroxide-Mediated Polymerization" (NMP) mechanism. Although some side reactions may occur with time (increasing polydispersity), polymerization of MMA initiated by AIBN at low temperature (60°C) after bubbling of NO/NO2 is relatively fast, and the molecular weight is dictated by the amount of NO/NO2. Finally, for the first time, copolymerization of MMA with HEMA (10/1; v/v) has been controlled by this mixture of NO and NO2 although the reaction remains very fast (ca. 65% monomer conversion after 5 h at 60°C), which is of prime importance for coating applications. [less ▲]

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See detailControlled radical polymerization of halogenated monomers
Bodart, Vincent; Piette, Yasmine; Detrembleur, Christophe ULg et al

Patent (2012)

Process for the preparation of a halogenated polymer comprising a controlled radical polymerization step of at least one monomer containing at least one halogen-carbon bond performed in the presence of an ... [more ▼]

Process for the preparation of a halogenated polymer comprising a controlled radical polymerization step of at least one monomer containing at least one halogen-carbon bond performed in the presence of an organo-cobalt complex, said polymerization step being further carried out in the presence of at least one ligand. [less ▲]

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See detailControlled radical polymerization of halogenated monomers
Bodart, Vincent; Piette, Yasmine; Detrembleur, Christophe ULg et al

Patent (2012)

Process for the preparation of a halogenated polymer comprising a controlled radical polymerization step of at least one monomer containing at least one halogen-carbon bond, performed in the presence of ... [more ▼]

Process for the preparation of a halogenated polymer comprising a controlled radical polymerization step of at least one monomer containing at least one halogen-carbon bond, performed in the presence of an organo-cobalt complex, said polymerization step being further carried out in non-isotherm conditions. [less ▲]

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