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See detailFLOWCV - AN OPEN-SOURCE TOOLBOX FOR COMPUTER VISION APPLICATIONS IN TURBULENT FLOWS
Bung, Daniel B.; Valero Huerta, Daniel ULiege

in Proceedings of the 37th IAHR World Congress (2017, August)

Despite the continuous advances in numerical modeling methods and the continuous increase of computer power and storage capacities in the last decades, physical modeling remains a common technique for ... [more ▼]

Despite the continuous advances in numerical modeling methods and the continuous increase of computer power and storage capacities in the last decades, physical modeling remains a common technique for evaluation of flow processes. One major advantage of this classical approach is given by the transparency of experiments as the flow can be easily observed in the laboratory and effects of changing boundary conditions may be better understood. Nowadays, the flow is commonly captured in most experiments with means of digital cameras or high-speed cameras to get a better insight and for further analyses after the model test. Besides some well-known techniques, such Particle Image Velocimetry, some new methods can be found in Computer Vision disciplines allowing for more detailed investigation of the images. This paper presents two modules of the new open-source toolbox FlowCV which has been developed to be applied in hydraulic laboratories. The first module is given by a synthetic particle image generator which provides the user with particle images of a predefined motion and turbulence. The second module implements different Optical Flow methods for determination of obstacle movement (here: particle movement). The Farnebäck method, which is presented in this paper, gives dense velocity fields, i.e. velocity data for every image pixel. The Optical Flow results based on the synthetic images are then benchmarked against their predefined particle velocity. It will be shown that even smallest turbulent flow structures are adequately detected. [less ▲]

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See detailCrossoads ( août 2017) - chaque mercredi de 18h à20h - rediffusion: samedis de 22h à minuit
Sacré, Robert ULiege

Diverse speeche and writing (2017)

Programme radio hebdomadaire consacré aux musiques africaines-américaines ; streaming : www.equinoxefm.be ; podcasts www.mixcloud.com/robertsacre9

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See detailPrevalence of voice disorders among teachers at the beginning of their career
Schiller, Isabel ULiege

Poster (2017, August)

Due to the high vocal demands associated with their profession, teachers face an increased risk of developing voice disorders. Research suggests that up to 50 % of experienced teachers are affected. Even ... [more ▼]

Due to the high vocal demands associated with their profession, teachers face an increased risk of developing voice disorders. Research suggests that up to 50 % of experienced teachers are affected. Even student teachers, whose vocal load is still relatively low, report voice problems with a frequency of 20 % (Simberg, Laine, Sala, & Rönnemaa, 2000). Little is known about the prevalence of voice disorders among teachers at the very beginning of their career. In Germany, teachers must complete a two-year teaching practice as part of their professional training after they graduate from university, consisting of attending specialized courses and giving lessons. The aim of this symptom-based study was to determine the prevalence of voice problems among this population. A self-administered questionnaire was answered by 73 German teachers in teaching practice. The prevalence of a voice problem was defined based on the presence of two symptoms that persisted for a minimum of two weeks. Results revealed that 37 % of teachers had voice problems during their teaching practice. Among the most frequent symptoms were hoarseness, an urge to clear one’s throat and problems speaking at a loud voice. Considering that the participants had not even begun teaching full-time, the prevalence of reported voice problems is worrisome. It could be associated with their lacking experience in how to use their voice effectively. The findings highlight the necessity of early intervention programs focusing on vocal hygiene and effective voice use in classroom situations. [less ▲]

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See detailAssessment of Continuous Pain in Newborns admitted to NICUs in 18 European Countries
Anand, Kanwaljeet; Eriksson, Mats; Boyle, Elaine et al

in Acta Paediatrica (2017), 106(8), 1248-59

Aim: Continuous pain occurs routinely, even after invasive procedures, or inflammation and surgery, but clinical practices associated with assessments of continuous pain remain unknown. Methods: A ... [more ▼]

Aim: Continuous pain occurs routinely, even after invasive procedures, or inflammation and surgery, but clinical practices associated with assessments of continuous pain remain unknown. Methods: A prospective cohort study in 243 Neonatal Intensive Care Units (NICUs) from 18 European countries recorded frequency of pain assessments, use of mechanical ventilation, sedation, analgesia, or neuromuscular blockade for each neonate upto 28 days after NICU admission. Results: Only 2113/6648 (31·8%) of neonates received assessments of continuous pain, occurring variably among tracheal ventilation (TrV, 46·0%), noninvasive ventilation (NiV, 35· 0%), and no ventilation (NoV, 20· 1%) groups (p<0· 001). Daily assessments for continuous pain occurred in only 10·4% of all neonates (TrV: 14· 0%, NiV: 10· 7%, NoV: 7· 6%; p<0· 001). More frequent assessments of continuous pain occurred in NICUs with pain guidelines, nursing champions, and surgical admissions prompted (all p<0·01), and for newborns <32 weeks gestational age, those requiring ventilation, or opioids, sedatives-hypnotics, general anesthetics (O-SH-GA) (all p<0·001), or surgery (p=0· 028). Use of O-SH-GA drugs increased the odds for pain assessment in the TrV (OR:1· 60, p<0·001) and NiV groups (OR:1·40, p<0· 001). Conclusion: Assessments of continuous pain occurred in less than one-third of NICU admissions, and daily in only 10% of neonates. NICU clinical practices should consider including routine assessments of continuous pain in newborns. [less ▲]

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See detailResponders to platelet-rich plasma (PRP) in osteoarthritis: A technical analysis
MILANTS, Christophe ULiege; Bruyère, Olivier ULiege; Kaux, Jean-François ULiege

in BioMed Research International (2017)

Purpose. To evaluate the similarities and differences between the variety of platelet-rich plasma (PRP) formulations, preparation, and uses to try to determine the best responses for the treatment of knee ... [more ▼]

Purpose. To evaluate the similarities and differences between the variety of platelet-rich plasma (PRP) formulations, preparation, and uses to try to determine the best responses for the treatment of knee osteoarthritis. Materials and Methods. A comparison of the outcomes of randomized controlled trials (RCTs) included in the 3 most recent and high-quality meta-analyses to classify the different studies in 2 groups (bad responders group (BRG) and very good responders group (VGRG)). Results and Discussion. From the 19 RCTs analyzed, 7 trials were included in the VGRG and 4 in the BRG. In VGRG, 1 or 2 injections were performed in 4/7 trials, time between injections was 2 to 3 weeks in 4/5 studies with many injections, volume injected varied from 2.5 to 8 mL, and single spinning technique was used in 5/7 studies. PRP classification was Mishra 4B and PAWP2B𝛽 in 5/7 studies. The use of PRP with leukocytes is only found in the BRG. Conclusion. There is a lack of standardization in PRP preparation technique for knee osteoarthritis. However it appears that the use of a single spinning technique, a platelet concentration lower than 5 times the baseline, and avoidance of leukocytes should be preferred. [less ▲]

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See detailLa place des savoirs grammaticaux et lexicaux dans les référentiels de compétences (1999-2016) et dans certains manuels de langues modernes
Simons, Germain ULiege; Delbrassine, Daniel ULiege; Van Hoof, Florence ULiege et al

in Didactiques en pratique (2017), 3

Cet article propose d'abord une lecture critique des référentiels de langues modernes qui ont été en vigueur en Communauté française de Belgique entre 1999 et 2016. Y sont principalement analysés les ... [more ▼]

Cet article propose d'abord une lecture critique des référentiels de langues modernes qui ont été en vigueur en Communauté française de Belgique entre 1999 et 2016. Y sont principalement analysés les référentiels "Socles de compétences en langues modernes" et "Compétences terminales et savoirs requis en langues modernes". La deuxième partie de l'article porte sur l'analyse partielle de deux manuels, le "Nieuwe Tandem 2" et le "New Headway". Une des thèses des auteurs de l'article est que ces référentiels de compétences et ces supports didactiques peuvent accroître l'hétérogénéité des niveaux de maîtrise en langue et générer des inégalités dans l'apprentissage. L'article se termine en évoquant différentes pistes qui peuvent contribuer à limiter les risques identifiés. [less ▲]

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See detailForeseeing New Control Challenges in Electricity Prosumer Communities
Olivier, Frédéric ULiege; Marulli, Daniele; Ernst, Damien ULiege et al

in Proc. of the 10th Bulk Power Systems Dynamics and Control Symposium – IREP’2017 (2017, August)

This paper is dedicated to electricity prosumer communities, which are groups of people producing, sharing and consuming electricity locally. This paper focuses on building a rigorous mathematical ... [more ▼]

This paper is dedicated to electricity prosumer communities, which are groups of people producing, sharing and consuming electricity locally. This paper focuses on building a rigorous mathematical framework in order to formalise sequen- tial decision making problems that may soon be encountered within electricity prosumer communities. After introducing our formalism, we propose a set of optimisation problems reflecting several types of theoretically optimal behaviours for energy exchanges between prosumers. We then discuss the advantages and disadvantages of centralised and decentralised schemes and provide illustrations of decision making strategies, allowing a prosumer community to generate more distributed electricity (compared to commonly applied strategies) by mitigating over- voltages over a low-voltage feeder. We finally investigate how to design distributed control schemes that may contribute reaching (at least partially) the objectives of the community, by resort in to machine learning techniques to extract, from centralised solution(s), decision making patterns to be applied locally. First empirical results show that, even after a post-processing phase so that it satisfies physical constraints, the learning approach still performs better than predetermined strategies targeting safety first, then cost minimisation. [less ▲]

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See detailDesign and Synthesis of [18F]BPAM121, a PET-Probe Targeting AMPA-subtype Glutamatergic Receptors.
Manos-Turvey, Alexandra ULiege; Lemaire, Christian ULiege; Becker, Guillaume ULiege et al

Poster (2017, August)

AMPA receptors (AMPARs), one of three sub-groups of ionotropic glutamate receptors present in the central nervous system, are recognised for their involvement in long-term potentiation (LTP), and learning ... [more ▼]

AMPA receptors (AMPARs), one of three sub-groups of ionotropic glutamate receptors present in the central nervous system, are recognised for their involvement in long-term potentiation (LTP), and learning and memory processes. [1] They represent a valid cognitive enhancer target, particularly in the fight against Alzheimer’s disease (AD). [2,3] Benzothiadiazine 1,1-dioxides, such as BPAM121, have emerged as important allosteric modulators of AMPARs, working solely in the presence of the endogenous transmitter. [4] Synthesis of BPAM121 labelled with fluorine-18 was proposed, to investigate the utility of this molecule as a PET probe in vivo, and evaluate its potential as an AD diagnostic tool (Figure 1). [Figure 1. a) Structure of BPAM121, b) Established radiochemical synthesis of [18F]BPAM121.] This work documents the successful optimization of synthesis, purification and formulation of [18F]BPAM121 using an automated FASTlab (GE Healthcare) synthesizer. In particular, the influence of higher-level [18F]fluoride ion starting concentrations on final product formulation requirements is discussed. Initial results revealed [18F]BPAM121 successfully passes the blood brain barrier, and further biological studies are currently underway. References [1] S. F. Traynelis et al. Pharmacol. Rev. 2010, 62, 405-496. 
 [2] J. Keifer, Z. Zheng, Eur. J. Neurosci. 2010, 32, 269-277. 
 [3] L. Gao et al. J. Neurochem. 2016, 136, 620-636. 
 [4] P. Francotte et al. J. Med. Chem. 2010, 53, 1700-1711. 
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See detailEvaluation of two intravaginal implants for the synchronization of estrus in Criollo cattle in Peru
Ordonez, Cesar; Ampuero, Enrique; Huanca, Nancy et al

Poster (2017, August)

The objective of this study was to compare the effect of two vaginal implants protocols on the follicular characteristics, the vaginal electrical resistance and the pregnancy rate of criollo cattle reared ... [more ▼]

The objective of this study was to compare the effect of two vaginal implants protocols on the follicular characteristics, the vaginal electrical resistance and the pregnancy rate of criollo cattle reared in altitude (3100 meters). All the cows (n=53) were selected after manual palpation and ultrasound examinations of their genital tract. All the cows had a body condition between 2.5 and 3.5 (range 1 to 5). On day 1 et for 7 days the first group of cows (n=23) was treated with 1,38 g of progesterone (Easi-breedTM CIDR® Zoetis) and the second group (n=30) with 1 g of progesterone (DIB system Agrihealth New Zealand). All the cows were treated at day 1 with 2 mg of estradiol benzoate (im), at day 9 with 2 ml of prostaglandin (im) and at day 10 with 1 mg of estradiol benzoate. A timed artificial insemination was realized 54 hours after the CIDR® or DIB removal. The pregnancy diagnosis was made by ultrasound 45 days later. Vaginal conductivity, diameter and perimeter of the follicle were measured at the time of insemination. There were no significant differences (p> 0.05) between both treatments in the electrical resistance of the vaginal mucus, diameter and perimeter of the preovulatory follicule. The averages of these variables respectively were 233 ± 36 ohms, 9.1 ± 1.9 mm and 24.6 ± 4.7 mm. Pregnancy rates of cows treated with DIB and CIDR respectively were 63.3 % and 69.6%. No significant statistical differences (p> 0.05) have been seen. In conclusion, both treatments showed similar ovarian response, electrical resistance and pregnancy rate in criollo cattle reared in altitude. [less ▲]

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See detailLa difficile jointure des directives EU anti-BEPS et des traités fiscaux
Docclo, Caroline ULiege

in Fiscologue International = Fiscoloog internationaal (2017)

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See detailHigh School Sport in Belgium (Wallonia)
Cloes, Marc ULiege

Conference (2017, July 31)

In Belgium, since 1969, sport is a competence under the control of public authorities defined according to the linguistic regime. As in most Western European countries, sport has been compartmentalised by ... [more ▼]

In Belgium, since 1969, sport is a competence under the control of public authorities defined according to the linguistic regime. As in most Western European countries, sport has been compartmentalised by giving rise to three main types of practice: "professional", "traditional" and "alternative" sports (Diegel, 1995). Clubs linked to sports federations constitute the local setting up of the sports organization, which is largely a majority (Zintz, 2014). Other operators from the public domain and the private sphere coexist (Cloes, 2012). In the school environment, sport can be found in three contexts: within the compulsory curriculum (physical education), integrated to extracurricular activities (activities organized during recess or free periods), and peripheral activities (use of school sports facilities by organizers who are not belonging to the school actors). If inter-school competitions are organized by several school sports federations (depending to the educational network), they are far from reaching the interest and involvement reached by the competitions managed by the traditional sports federations. So there is hardly any systematic sports training in French-speaking Belgian schools. Some PE teachers propose voluntary training sessions but there are less and less connections between their actions and sport clubs. On the other hand, young sportsmen appointed by the Minister of Sports have a special status enabling them to benefit facilities to pursue their double career. They are sometimes gathered in special organizations - sport-studies or development centers - which have been the subject of several studies (Cloes et al., 2002, Lacrosse et al., 2014, Theunissen et al., 2016) but PE teachers are very few involved in these development opportunities. In many situations of partnership between the school and sports structures, their role is often limited to a simple accompanying action (sports days, projects "My club-My school." Cloes (2017) insisted however on the need to make them a priority in the coordination of the preparation of physically educated citizens. References Cloes, M. (2012). La Wallonie en mouvement : vers une culture sportive et de l’activité physique ? In, M. Germain et R. Robaye (Eds.), L'état de la Wallonie. Portrait d'un pays et de ses habitants – 2011. (pp. 70-80). Namur : Les éditions namuroises. Available on Internet : http://hdl.handle.net/2268/117294 Cloes, M. (2017). Preparing physically educated citizens in physical education. Expectations and practices. Retos, 31, 245-251. Available on Internet : http://recyt.fecyt.es/index.php/retos/article/view/53497/32304 Cloes, M., Schelings, V., Ledent, M, & Piéron, M. (2002). Sport-études : comparaison des caractéristiques motivationnelles et des relations sociales des élèves sportifs et de leurs condisciples. eJRIEPS (e Journal de la Recherche sur l'Intervention en Éducation Physique et Sport), 1, 57-72. Available on Internet: http://hdl.handle.net/2268/10187 Diegel, H. (1995). Sport in changing society – Sociological essays. Schorndorf: Verlag Karl Haufmann. Lacrosse, Z., Martin, V., & Cloes, M. (2014, July). Analyse qualitative du fonctionnement du centre de formation d’une fédération sportive. Paper presented at the 8ème biennale de l’ARIS ‘Temps, temporalités et intervention en EPS et en sport’, Genève, Suisse. Available on Internet: http://hdl.handle.net/2268/170020 Theunissen, C., Meys, G., & Cloes, M. (2016). Encadrement du staff autour du double projet des sportifs dans un centre de formation en handball. Revue de l’Éducation physique, 56, 1/2, 20. Disponible sur Internet: http://yessport.be/educationphysique/file/REVUE_1_ET_2_2016_-2eme_COLLOQUE_GUY_NAMUROIS.pdf ou http://orbi.ulg.ac.be/handle/2268/199016 Zintz, T. (2014). Module 3 - Le paysage sportif : du pratiquant aux fédérations. Thématique 1 - Cadre institutionnel et législatif. Cours généraux de la formation ‘Moniteur Sportif Initiateur’. Brussels, Belgium : Administration des sports, Fédération Wallonie-Bruxelles. Internet : http://www.sport.cfwb.be/index.php?id=7370 [less ▲]

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See detailDynamicized semantic maps of content words. Comparing long-term lexical changes in Ancient Egyptian and Greek
Georgakopoulos, Athanasios ULiege; Polis, Stéphane ULiege

Conference (2017, July 31)

This paper aims at demonstrating how information on the paths of semantic extensions undergone by content words may be incorporated into semantic maps. For this purpose, particular changes that affected ... [more ▼]

This paper aims at demonstrating how information on the paths of semantic extensions undergone by content words may be incorporated into semantic maps. For this purpose, particular changes that affected the meanings of words in the course of the Ancient Egyptian and of the Ancient Greek language history are investigated. [less ▲]

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See detailThermoelectric properties of heavily-doped Fe2YZ full-Heusler compounds
Lemal, Sébastien ULiege; Ricci, Fabio ULiege; Verstraete, Matthieu ULiege et al

Poster (2017, July 31)

Fe2YZ full-Heusler compounds were recently predicted to exhibit very large thermoelectric power factors [Phys. Rev. Lett. 114, 136601 (2015)]. Combining first-principles density functional theory ... [more ▼]

Fe2YZ full-Heusler compounds were recently predicted to exhibit very large thermoelectric power factors [Phys. Rev. Lett. 114, 136601 (2015)]. Combining first-principles density functional theory calculations within a hybrid functional approach and Boltzmann semi-classical transport theory, we investigate the limits of the rigid band doping approximation, and the properties of heavily n-type doped full-Heusler Fe2YZ1-xAx compounds. Using a supercell approach and including explicit dopant impurities, we recover in some cases giant thermoelectric power factors, as previously predicted within the rigid band approximation. In others the effect on the electronic structure is very different from rigid shifts. Interestingly, we find that some systems present a magnetic instability consistent with the Stoner model, and evolve towards a ferromagnetic half-metallic ground state, with a strongly modified power factor. Our results show the promise of the heavily-doped phases of the studied Fe2YZ1-xAx compounds for Seebeck and spin-dependent Seebeck applications. [less ▲]

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See detailLegal, official, academic and "trading" norms in higher DRC's education
Poncelet, Marc ULiege

Conference (2017, July 31)

Rule of legal, official, practical norms in DRC university

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See detailCation Distribution Dependent Magnetic Properties in CoCr 2-x Fe x O 4 (x= 0.1 to 0.5): EXAFS, Mӧssbauer and Magnetic Measurements
Kumar, Durgesh; Banerjee, Alok; Mahmoud, Abdelfattah ULiege et al

in Dalton Transactions (2017), 46

In this report, we have examined the evolution of the structure and rich magnetic transitions such as a paramagnetic to ferrimagnetic phase transition at the Curie temperature (TC), spiral ordering ... [more ▼]

In this report, we have examined the evolution of the structure and rich magnetic transitions such as a paramagnetic to ferrimagnetic phase transition at the Curie temperature (TC), spiral ordering temperature (TS) and lock-in temperature (TL) observed in the CoCr2O4 spinel multiferroic after substituting Fe. The crystal structure, microstructure and cation distribution among the tetrahedral (A) and octahedral (B) sites in the spinel lattice are characterised by X-ray diffraction, transmission electron microscopy, Extended X-ray Absorption Fine Structure (EXAFS) and Mössbauer spectroscopy. Due to the same radial distances of the first coordination shell in both tetrahedral and octahedral environments observed in EXAFS spectra, the position of the second coordination shell specifies the preference of more Fe ions towards the A site at x = 0.1. At x = 0.5, more Fe ions favour the B site. The cation distribution quantitatively obtained from the Mössbauer spectral analysis shows that while 60% of Fe ions occupy the A site in x = 0.1, 40% occupy it in x = 0.5. Surprisingly at x = 0.3, Fe ions are distributed equally among the A and B sites. dc magnetization reveals an increase in TC from 102 K to 200 K and in TS from 26 to 40 K with an increase in Fe concentration, indicating an enhancement in A–B exchange interaction at the expense of B–B. No report has until now demonstrated such an enhancement in TS either in pure or in doped CoCr2O4. Furthermore, frequency-dependent ac susceptibility (χ) data fitted with different phenomenological models such as the Néel–Arrhenius, Vogel–Fulcher and power law confirm a spin-glass and/or cluster-glass behaviour in nanoparticles of CoCr2−xFexO4. [less ▲]

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See detailLe maraîchage périurbain à Libreville et Owendo (Gabon) : pratiques culturales et durabilité
Bayendi-Loudit, Sandrine ULiege; Ndoutoume Ndong, Auguste; Francis, Frédéric ULiege

in Cahiers Agricultures (2017)

In Gabon, peri-urban gardening is an opportunity to provide vegetables to the main cities, such as Libreville and Owendo. Following a survey conducted in three market gardening areas, an inventory was ... [more ▼]

In Gabon, peri-urban gardening is an opportunity to provide vegetables to the main cities, such as Libreville and Owendo. Following a survey conducted in three market gardening areas, an inventory was conducted on the socio-economic characteristics, the diversity of crops, and pesticide uses. The cropped areas range from 0.08 ha to 0.4 ha per farmer, according to the site. National operators represent 51%, while people from Burkina Faso manage 40% of vegetable production. The most cultivated species throughout the year are amaranth (Amaranthus hybridus L.), lettuce (Lactuca sativa L.), Guinea sorrel (Hibiscus sabdariffa L.) and black nightshade (Solanum nigrum L.). The most important pests are Aphididae and some beetles. The most commonly used plant protection products are insecticides, mainly conventional neurotoxic. Best crop monitoring, pest control including pesticide application reduction, and the possibility to offer microcredit systems to small producers would help increasing peri-urban healthy vegetable production and increase local food autonomy [less ▲]

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See detailEl impacto del fin del “giro al la izquierda” sobre las relaciones entre China y América Latina
Wintgens, Sophie ULiege

Conference (2017, July 28)

La llegada de China en América Latina a finales de los años 2000 se ha presentado como una nueva opción en el contexto histórico de un “movimiento pendular” que siempre ha visto los países latino ... [more ▼]

La llegada de China en América Latina a finales de los años 2000 se ha presentado como una nueva opción en el contexto histórico de un “movimiento pendular” que siempre ha visto los países latino-americanos girar principalmente en torno a Europa y sus antiguas potencias coloniales o en torno a los Estados Unidos. En el marco de esa dinámica del “triángulo Atlántico” en la que se encuentra encerrada América Latina, China ha también beneficiado de un entorno regional propicio como consecuencia de factores tanto estructurales (las debilidades del regionalismo latinoamericano), como coyunturales (la escalada de la “nueva” izquierda sudamericana). El inicio de la década de 2010, sin embargo, parece marcar el final del “giro à la izquierda” y los límites del modelo de desarrollo extractivo adoptado por la mayoría de los gobiernos progresistas latino-americanos. Al mismo tiempo, las autoridades chinas han también iniciado un cambio de modelo de desarrollo económico con el undécimo Plan Quinquenal (2006-2010) para que sea más autocentrado y basado en la producción de productos de alta calidad. Basándose en estas observaciones, este ponencia interroga el impacto de este contexto sobre las relaciones entre China y América Latina. [less ▲]

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See detailSpray-drying as a tool to disperse conductive carbon inside Na2FePO4F particles by addition of carbon black or carbon nanotubes to the precursor solution
Mahmoud, Abdelfattah ULiege; Caes, Sebastien; Brisbois, Magali et al

in Journal of Solid State Electrochemistry (2017)

In this work, Na2FePO4F-carbon composite powders were prepared by spray-drying a solution of inorganic precursors with 10 and 20 wt% added carbon black (CB) or carbon nanotubes (CNTs). In order to compare ... [more ▼]

In this work, Na2FePO4F-carbon composite powders were prepared by spray-drying a solution of inorganic precursors with 10 and 20 wt% added carbon black (CB) or carbon nanotubes (CNTs). In order to compare the effect of CB and CNTwhen added to the precursor solutions, the structural, electrochemical, and morphological properties of the synthesized Na2FePO4F-xCB and Na2FePO4F-xCNT samples were systematically investigated. In both cases, X-ray diffraction shows that calcination at 600 °C in argon leads to the formation of Na2FePO4F as the major inorganic phase. 57Fe Mössbauer spectroscopy was used as complementary technique to probe the oxidation states, local environment, and identify the composition of the iron-containing phases. The electrochemical performance is markedly better in the case of Na2FePO4F-CNT (20 wt%), with specific capacities of about 100 mAh/g (Na2FePO4F-CNT) at C/4 rate vs. 50 mAh/g for Na2FePO4F-CB (20 wt%). SEM characterization of Na2FePO4F-CB particles revealed different particle morphologies for the Na2FePO4F-CNT and Na2FePO4F-CB powders. The carbon-poor surface observed for Na2FePO4FCB could be due to a slow diffusion of carbon in the droplets during drying. On the contrary, Na2FePO4F-CNT shows a better CNT dispersion inside and at the surface of the NFPF particles that improves the electrochemical performance. [less ▲]

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