bluuebunny/crossref_metadata_2025 huggingface dataset:
Manly Games, Athletic Sports and the Commodification of Scottish Identity: Caledonian Gatherings in New Zealand to 1915
Authors: Bueltmann Tanja
Published: October 2010

This article explores the development of Caledonian Gatherings in New Zealand from their first emergence in the 1860s until 1915. As one of the defining features of Scottish immigrant community life in the Diaspora, the Gatherings are a global phenomenon. In New Zealand, their development is intrinsically bound to that of Scottish associations, with Caledonian Games being, in fact, the crucial motor for the associations’ rise. The assessment of Caledonian Gatherings hence provides the key to understandig the Scots’ associational culture in New Zealand. At the same time, however, the Gatherings were not an exclusive Scottish event, the article documenting their wider community relevance. Outside of the tighter circle of Scots intent on the promotion of Caledonian sports, the Gatherings soon became a favourite holiday pastime throughout New Zealand. From the late 1880s, greater emphasis was placed on the athletic components of the programme. This is suggestive of the the tensions between Scottish traditionalists keen on maintaining the Games’ authentic character, and those seeking to promote them as amateur or professional athletic gatherings. By scrutinising the ways in which ‘Caledonia’ was commodified, and developed as a successful brand, the article explores the Gatherings’ dual purpose. Though born out of an ethnic tradition – hence serving as a site of memory – the article argues that Caledonian Gatherings were a central means for the Scots involved in their organisation to claim respectability in civic life.
Active Sport Tourists: Sport Event Image Considerations
Authors: Kaplanidou Kiki
Published: October 2010

Sport events can be used as tourist attractions by destinations that seek to attract large numbers of tourists in their locale. This study examines the event image perceptions of active sport tourists (participants) of an international marathon event following the destination image
measurement paradigm. The census of active sport tourists (N = 2,000) who traveled from abroad to participate in the event was used to elicit image associations about the event. Respondents were asked to indicate the three words that come to mind when they think of the event after they
returned to their homes (posttrip phase). Both qualitative and quantitative approaches were utilized. For the qualitative approach, the acquired words (n = 1,015) were classified into six image themes (historical, emotional, organizational, physical, environmental, and social). The
quantitative approach included a frequency analysis of prespecified key words associated with each dimension and revealed that the emotional theme was more frequently mentioned. These results suggest active sport tourists' event image perceptions are related to the themes above with emotional
aspects being more dominant during the postevent recall of the event. More research is needed with different types of active sport tourists to be able to generalize these results.
Le discours cinématographique de Clint Eastwood : individualisme et humanisme
Authors: Szlamowicz Jean
Published: October 2010

Résumé L' uvre de Clint Eastwood développe un discours politique concernant les rapports de l'individu et de la cité. Ce discours est à apprécier dans le cadre de l'individualisme comme valeur politique américaine et de l'individualisme méthodologique. Parmi ses thématiques principales, Eastwood s'intéresse aux conflits et la légitimité de la violence, à la solitude des faibles et à la question de la liberté individuelle. Dans les rapports horizontaux, il montre la spécificité individuelle face à la pression du communautarisme, de l'appartenance sociale ou sexuelle. Dans les rapports verticaux, c'est leur fragilité face aux pressions de toutes sortes, institutionnelles, religieuses ou criminelles qui souligne une lutte de l'individu face aux pouvoirs. Certains héros ou figures allégoriques interviennent alors pour souligner la violence inhérente à ces rapports. Son discours est parfois considéré comme sécuritaire, voire « fascisant » par certains critiques, ce qui pose la question des tensions idéologiques qui entourent son cinéma. Face à l'idéologie gramscienne des critiques, Eastwood affirme une position individualiste tocquevillienne originale qui impose une certaine vision du processus démocratique américain.
Sur Le tombeau d'Alexandre (1992) de Chris Marker. Réflexion sur la dissolution révolutionnaire d'une personnalité artistique
Authors: Granik Anton , Rozin Philippe
Published: October 2010

Résumé Nous proposons dans cet article d'étudier Le tombeau d'Alexandre de Chris Marker. Dans ce film, le cinéaste français met en scène la relation très particulière qu'il a entretenue avec le cinéaste russe Alexandre Medvedkine (particulièrement actif pendant la guerre civile de 1918-1921 et inventeur d'un nouveau format documentaire, le ciné-train). Le film de Chris Marker prend pour objet le cheminement intellectuel de son ami Medvedkine et mène une investigation sur les relations entre propagande politique et intégrité artistique. Il étudie tout particulièrement le parallélisme de destin et d'engagement politique entre Medvedkine et Vertov et aborde la question des conditions esthétiques de fabrication des images animées en insistant sur le rôle cardinal joué par la propagande, une propagande appréhendée comme une matrice indissociablement politique, biographique et esthétique.
Les triangulations précoces
Authors: Gérard Christian
Published: October 2010

Résumé Les triangulations précoces sont considérées comme des pré-requis préalables à l’élaboration du fantasme de scène primitive, les identifications primaires à chaque parent y tenant une place de premier plan. La prise en compte des parents dans leur réalité corporelle est soulignée, y compris celle du père : un « père primaire ». L’attention portée aux aléas de ces articulations de la réalité des parents, tant psychique que physique, permet une meilleure compréhension des éventuels dysfonctionnements de l’élaboration du fantasme de scène primitive et des pathologies actuelles.
Autoréférence et exploitation opportuniste d'un environnement hypermédia « ouvert » : étude de l'activité d'utilisateurs
Authors: Leblanc Serge , Saury Jacques , Sève Carole
Published: October 2010

Résumé Cet article propose une présentation de quelques résultats concernant les « situations problématiques » et les usages « prometteurs » d’un environnement hypermédia « ouvert ». L’analyse de l’activité des utilisateurs de cet environnement en situation réelle de formation a été menée à partir du cadre théorique et méthodologique du cours d’action. La description des cours d’action des utilisateurs fait apparaître une errance interprétée comme une perte de sens et une désorientation mais également une capacité des utilisateurs à « s’autoréférencer » et à exploiter de manière opportuniste les offres de cet environnement « ouvert ».
L'expérience des apprenants en e-formation : revue de littérature
Authors: Dieumegard Gilles , Durand Marc
Published: October 2010

Résumé Cet article présente une revue de littérature internationale portant sur l’expérience des apprenants dans des dispositifs d’e-formation. 43 publications ont été étudiées. Leurs résultats ont été organisés selon cinq thèmes : a) l’usage des technologies ; b) l’organisation de l’activité d’étude ; c) la médiatisation des interactions ; d) la collaboration dans des e-communautés, e) le lien entre interactions en ligne et apprentissage. Ils montrent l’importance d’aspects peu pris en compte dans les dispositifs d’e-formation : l’autonomie réelle des apprenants, la dimension temporelle dans leur activité d’étude et les interactions, les limites des interactions asynchrones.
Lorsque le développement des TIC et l'évolution des théories de l'apprentissage se croisent
Authors: Marquet Pascal
Published: October 2010

Résumé Dans cet article, nous proposons d’analyser rétrospectivement ce que les possibilités offertes par les TIC et les doctrines éducatives dominantes ont produit comme dispositifs d’enseignement par système technique interposé. Nous évoquons un certain nombre de triplets comme EAO/béhaviorisme/micro-informatique, EIAO/constructivisme/hypermédia, EIAH/cognitivisme/ multimédia, EAD/socio-constructivisme/Internet. Nous montrons que chaque génération de dispositifs est intégrative au sens où elle contient la précédente et la dépasse. Sous cet éclairage, nous dessinons les contours de l’un des triplets émergents que sont les ENTAP, leur genèse instrumentale, à l’ère du tout-numérique. Nous avançons l’idée que les plates-formes les plus récentes consacrent la fusion des pratiques d’enseignement présentiel et à distance et nécessitent un nouveau cadre théorique, que nous esquissons, pour rendre compte de leurs usages.
« L'autodidacte » : un Robinson Crusoé de la formation ?
Authors: Cyrot Pascal
Published: October 2010

Résumé L’autodidacte est souvent perçu par le sens commun comme un auto-apprenant solitaire, autarcique, donnant ainsi envie de le comparer au modèle de Robinson Crusoé. Cependant, si les spécialistes affirment l’écart entre les deux modèles, rares sont les études qui travaillent de façon systématique les relations sociales de l’autodidacte. L’article s’emploie alors à montrer cet écart, affirmant ainsi le niveau de sociabilité de l’autodidacte et la nature des relations sociales d’apprentissage, ou plus largement « de soutien », qu’il vit durant son autodidaxie. En outre, si l’article refuse de voir une équivalence entre l’autodidacte et le mythe de Robinson, il considère que le personnage originel de D. Defoe est un guide intéressant pour comprendre l’autodidaxie contemporaine.
L'information pour le développement des savoirs en soutien à la résilience des proches soignants
Authors: Lefebvre Hélène , Pelchat Diane , Levert Marie-Josée , David Claire
Published: October 2010

Résumé Cette étude préliminaire avait pour but de documenter les besoins d’information des proches soignants, les sources d’information et les stratégies utilisées pour obtenir de l’information. Deux groupes de discussion ont été réalisés : l’un auprès de proches soignants de personnes ayant subi un traumatisme craniocérébral, un accident vasculaire cérébral ou une blessure médullaire, et l’autre auprès de professionnels de la santé de différentes disciplines impliqués auprès de ces patients. Les résultats montrent que les proches ont besoin d’information sur l’impact des incapacités dans leur vie quotidienne et sur les moyens pour la repérer. Du point de vue des professionnels, le besoin d’information des proches concerne notamment les incapacités consécutives au problème de santé et les stratégies pour y faire face. Selon les professionnels, les proches comblent leurs besoins d’information par la consultation de l’Internet, des médias, de la documentation écrite et d’échanges avec les professionnels de la santé et les pairs.
Savoir poser une problématique, un levier du développement professionnel
Authors: Floro Michel , Lespinat Céline
Published: October 2010

Résumé Cette recherche a pour finalité de mieux comprendre la genèse des compétences professionnelles des professeurs des écoles. Nous questionnons les origines de leur formation, pour élucider comment, elles se forment. Pour cela nous étudions les pratiques des stagiaires en situation, dans le but d’identifier les repères de la réussite et les obstacles à leurs évolutions professionnelles. Dans cet article, nous étudions en particulier comment se construisent et se développent des savoirs de métier chez un enseignant confronté à des événements de classe imprévus. L’interprétation des observations utilise un modèle de prise de risque qui fait se dégager des jeux stratégiques de brouillage comme un moyen pour limiter ceux que produit la situation. Il ressort de cette étude qu’une compétence indispensable au développement professionnel est la capacité à problématiser et clarifier la question problématique qui organise et donne sens aux savoirs à transmettre. Notre démarche utilise le dispositif de formation initiale comme dispositif expérimental.
Valeur, espérance de réussite, et formation d'adultes : pertinence du modèle d'expectancy-value en contexte de formation universitaire pour adultes
Authors: Bourgeois Étienne , de Viron Françoise , Nils Frédéric , Traversa Jacqueline , Vertongen Gil
Published: October 2010

Résumé À ce jour, de plus en plus d’adultes, âgés de plus de 25 ans, retournent à l’université pour satisfaire un besoin de formation continue, voire pour entamer un cycle d’études complet. La présente étude vise à valider un questionnaire mesurant les concepts d’ expectancy et de valeur perçue de la formation (Eccles & Wigfield, 2000, 2002) auprès d’un public d’adultes en reprise d’études. Les données ont été collectées par questionnaire, auprès de 300 d’entre eux. Les analyses factorielles exploratoires révèlent que ces étudiants non-traditionnels distinguent clairement les items évaluant, d’une part, leur attente de réussite dans la formation et, d’autre part, les quatre dimensions constitutives de la valeur subjective des activités académiques, à savoir la valeur intrinsèque, l’utilité perçue, l’importance, et le coût. Après avoir été maintes fois éprouvé auprès de populations d’enfants et d’adolescents, ce paradigme révèle, pour la première fois, sa pertinence pour appréhender la motivation d’une population d’adultes en reprise d’études.
Recherches en didactique et développement professionnel de formateurs d'enseignants
Authors: Brau-Antony Stéphane
Published: October 2010

Résumé L’article présente un dispositif de formation qui s’inscrit dans la perspective d’un développement professionnel de formateurs d’enseignants d’éducation physique et sportive. Il part de l’hypothèse selon laquelle les recherches en éducation peuvent constituer un levier permettant de professionnaliser les formateurs à condition que la formation ait un rapport de proximité avec leur activité professionnelle habituelle. La première partie décrit le dispositif de formation en montrant comment il est possible d’utiliser les connaissances produites par les recherches en didactique à des fins professionnelles, notamment à travers l’observation d’enseignants en train de faire la classe. La seconde partie tente d’évaluer les retombées de ce type de formation sur les pratiques professionnelles des formateurs.
Construire l'auto-efficacité par l'analyse de l'activité en formation des cadres et dirigeants de la santé publique
Authors: Nagels Marc
Published: October 2010

Résumé L’objet de cette recherche était de mesurer la contribution de l’analyse de l’activité au développement de l’auto-efficacité au travail en référence à la théorie sociocognitive et à la théorie de la conceptualisation dans l’action. Notre population est constituée de cadres et de dirigeants de la santé publique en formation à l’École des hautes études en santé publique. Un dispositif d’autoconfrontations a été organisé pour évaluer la corrélation entre l’analyse réflexive de son activité et le niveau d’auto-efficacité. L’auto-efficacité des élèves a été mesurée prétest et posttest. Après vérification statistique, nous observons que l’analyse de l’activité a eu un effet sur le groupe test et, plus précisément, sur les personnes de faible niveau initial d’auto-efficacité. Nous en concluons que l’analyse de l’activité et l’agentivité contribuent explicitement à la formation des compétences.
L'intérêt clinique du concept d'efficacité personnelle
Authors: de Almeida Carapato Elodia , Petot Jean-Michel
Published: October 2010

Résumé La notion de sentiment d’efficacité personnelle se ramène à une idée très simple mais très éclairante, issue de la réflexion sur la pratique des thérapies comportementales : la capacité d’une personne à entreprendre certaines actions dépend largement de sa croyance dans cette capacité. Cette théorie éclaire les premières contributions de Bandura : la notion d’apprentissage vicariant, et donc la technique psychothérapeutique du modeling , qui est interprétée, comme le sont finalement tous les procédés des thérapies cognitivo-comportementales, comme autant de moyens d’augmenter le sentiment d’efficacité du patient et donc son efficacité réelle. La croyance dans sa propre efficacité apparaît dès lors comme un phénomène fondamental dans l’ensemble des processus qui assurent l’adaptation, la santé et le bien-être psychiques. Cette théorie rend également compte des troubles psychopathologiques les plus courants -anxiété, dépressions, troubles du comportement alimentaire et addictions - en termes de défaillances spécifiques de la croyance dans sa propre efficacité.
Orientation des adultes et formation tout au long de la vie
Authors: Aubret Jacques , Demouge Nicole
Published: October 2010

Résumé À partir d’un recueil d’entretiens biographiques réalisés sur un public d’adultes engagés dans un stage de formation dans une période de mobilité professionnelle, nous analysons les rapports que l’on peut établir entre l’orientation des adultes et les injonctions à la formation tout au long de la vie. Deux variables (genre et statut professionnel), particulièrement influentes sur la carrière professionnelle, sont prises en compte. Les résultats montrent que les récits manifestent, mais de manière différenciée dans les groupes constitués sur la base du croisement des variables, un certain réalisme des sujets en ce qui concerne l’expression de leurs aspirations : ouverture pour les uns, adaptation aux environnements du travail et de la famille pour d’autres, résignation pour d’autres encore. Ils valident l’idée que l’entrée en formation n’est qu’un moment dans un processus d’orientation et que les pratiques d’accompagnement des adultes, telles que le bilan de compétences, trouvent leur justification dans la nécessité de proposer aux étapes cruciales de leur parcours de vie des activités de réflexion sur soi, d’analyse de l’expérience, d’aide à l’évaluation, susceptibles de développer de nouvelles motivations à s’investir, lorsque les contraintes du travail et de l’environnement tendent à enfermer les personnes sur elles-mêmes.
La décision de la personne adulte à entrer en formation dans le secteur social
Authors: Prestini Mireille
Published: October 2010

Résumé Ce qui apparaît spécifique à la situation de la personne adulte à l’entrée en formation, c’est bien la décision qu’elle a prise, de s’engager dans une formation. Pour celle-ci, vivre une formation ne va pas de soi et signifie un véritable engagement qui remet en cause sa situation actuelle et l’oblige à réfléchir à la mise en œuvre de cette formation en articulation avec l’ensemble de ses préoccupations, responsabilités et activités. L’étude à partir de 32 entretiens d’adultes à l’entrée en formation dans le secteur social met en évidence que le processus de décision imbrique des facteurs contextuels mais aussi un environnement vocationnel (rapport à des valeurs pour une cohérence de soi) dans un rapport au temps. La décision se construit à partir d’un fait-déclencheur. La prise en compte de celui-ci apparaît être un axe intéressant dans la question de la mobilité de la personne et de l’orientation tout au long de la vie.
ROLE OF NÉEL AND BROWNIAN RELAXATION MECHANISMS FOR WATER-BASED Fe3O4 NANOPARTICLE FERROFLUIDS IN HYPERTHERMIA
Authors: Zhang Xuefeng , Chen Shihwei , Wang Huay-Min , Hsieh Shu-Ling , Wu Chun-Hsin , Chou Hsuan-Hung , Hsieh Shuchen
Published: October 2010

Hydrophilic Fe3O4 nanoparticles with a mean diameter size of 15 nm were synthesized by means of the direct reduction of FeCl3 and FeCl2 in an aqueous solution. The heating properties of Fe3O4 nanoparticles under an alternating magnetic field were investigated in a frequency range of 50–500 kHz and a magnitude range of 3.1–5.0 kA/m. To distinguish the roles of Néel and Brownian relaxation mechanisms, polydimethylsiloxane (PDMS) and water were employed as a medium, in which PDMS plays a significant role of eliminating the effect of Brownian relaxation. It is experimentally and theoretically confirmed that, for the Fe3O4 /water system, high-specific absorption rates are due to a combination of both mechanisms, with an enhanced contribution due to Néel relaxation with increasing frequency and magnitude of the alternating electromagnetic field. The contribution efficiency of Néel relaxation increases from 36–56% by increasing the electromagnetic field frequency from 50–300 kHz, and then retains a saturated value of ~ 56% at 300–500 kHz. Moreover, a linear increase of the contribution efficiency of Néel relaxation at 300 kHz was observed from 55–65% by increasing the magnitude of electromagnetic field at 3.1–5.0 kA/m. The current research can be widely-expanded to explain the electromagnetic heating effect of other ferrofluid systems.
Preparation and Characterization of New Oxyfluoride Phases (Ba,Na)(Ti,Mg)(O,F)
Authors: Talantikite-Touati Djahida , Benzïada Laldja
Published: October 2010

Oxyfluoride phases have been synthesized in free atmosphere, using the initially synthesized perovskite BaTiO3 and the fluorides NaF and MgF2. The purity of BaTiO3 and oxyfluorides has been checked by X–Ray diffraction (XRD).The microstructures of these phases are observed by scanning electron microscopy. The phase transitions have been investigated by dielectric measurements and differential scanning calorimetry (DSC).
Theoretical and Experimental Analyses of Colloidal Processing of Nanoparticles
Authors: Hirata Yoshihiro , Matsushima Koichiro , Baba Shinichi , Matsunaga Naoki , Sameshima Soichiro
Published: October 2010

The stability of dispersed and flocculated colloidal particles under 1 atm and applied pressure was discussed thermodynamically with the activity and chemical potential defined by Henry’s law and Raoult’s law. The calculated result under 1 atm is represented by a colloidal phase diagram as functions of surface potential and solid content of particles. Application of pressure accelerates the phase transition from dispersed to flocculated suspension. The phase transition pressure, which is observed in the applied pressure-suspension height relation during pressure filtration at a constant crosshead speed of piston, is affected by (1) particle concentration, (2) particle size, (3) surface potential, (4) degree of dissociation of polyelectrolyte dispersant and (5) applied electric field (DC and AC). The influence of above factors was discussed theoretically and experimentally.
Improving the Porosity Features Control of Ceramic Cellular Components through a Modified Gelcasting Process
Authors: Lombardi Mariangela , Meille Sylvain , Chevalier Jérôme , Montanaro Laura
Published: October 2010

An innovative gelcasting procedure was successfully developed to produce cellular ceramic materials, having controlled porosity features, tailored for a specific application. This process combines a conventional gelcasting based on in situ polymerization of a natural gelling agent to a sacrificial template method, in which polyethylene (PE) spheres having a controlled size distribution are used as pore former. By a suitable selection of the PE spheres fraction and volume percentage, it is possible to modify some important porosity characteristics of the final component, such as the mean pore size, the total pore volume, the pore geometry as well as the pore interconnection number and size. The effectiveness and versatility of this procedure was demonstrated by exploiting it in the preparation of porous components made of several ceramic powders (alumina, zirconia, hydroxyapatite) different in terms of composition and size.
The Rapid Automated Materials Synthesis Instrument (RAMSI): A High Throughput Combinatorial Robot for Nanoceramics Discovery
Authors: Lin Tian , Kellici Suela , Gong Ke Nan , Thompson Kathryn , Darr Jawwad A.
Published: October 2010

A high throughput combinatorial robot RAMSI (Rapid Automated Materials Synthesis
Instrument) has been developed for nanoceramics synthesis. It can rapidly produce nanoparticle
libraries that can be used for new materials discovery. The RAMSI robot has 3 motor-driven axes
moving in X-Y-Z space and linking the synthesis, cleanup and printing sections. A High Throughput
Continuous Hydrothermal (HiTCH) flow synthesis reactor is contained within RAMSI, and reaches
significant production capability of 48 tubes of 50mL samples in 8 hours. Supported by the high
throughput hardware design, the control system adopts parallel operations and multi-task assignments.
Key strategies include intelligent supernatant detection, dot printing protocols and robot arm route
schedule etc. The commissioning of RAMSI showed its high efficiency by producing samples of
yttrium hydroxide doped with europium. In a 6-hour experiment, 8 unique 100mL samples were
synthesized then cleaned and printed into 96 dots (100 minutes only for synthesis time). The ceramic
dots were heat-treated at different temperatures up to 1200°C and affixed into a well-plate library. The
brightest phosphors could be readily identified by illumination under UV light.
A New Powder Filler, Obtained by Applying a New Technology for Fly Ash Inertisation Procedure
Authors: Bontempi Elza , Zacco Annalisa , Borgese Laura , Gianoncelli Alessandra , Ardesi Rosario , Depero Laura E.
Published: October 2010

In the last years several projects have been developed for treatment of fly ash with the aim of their reuse. A final target of these researches is to evaluate the real performance of the new materials obtained by the treatment and the actual and, if the case, potential markets for the foreseen products. Indeed, the use of a recycled inert would reduce the consumption of natural resources and this is one of the main environmental EU target. Examples are clinkering, road asphaltation and some construction work where specific performances are requested. Moreover, the reuse of inerted fly ash will obtain a reduction of carbon dioxide produced by the necessary treatments of primary materials, as limestone in concrete production.
At the University of Brescia (Italy) a new process, based on colloidal silica medium, has been developed to inertise fly ashes, containing heavy metals. This approach appears to be quite promising for industrial application in view of the easiness that can be foreseen in applying it to existing plants treating industrial fly ash. The obtained inert product is a powder, that can be employed as a filler in several application.
In this work we present first results about characterization of this new powder material, that can be applied as a filler.
Solvothermal Synthesis of ITO Nanoparticles Precisely Controlled in Size and Shape
Authors: Muramatsu Atsushi , Sasaki Takafumi , Endo Yosuke , Doi Yuka , Kanie Kiyoshi
Published: October 2010

Highly crystalline cubic indium tin oxide (ITO) nanoparticles with narrow size distribution were successfully prepared directly in one step from the mixed solution of indium and tin salts by the solvothermal method with lean ethylene glycol as a solvent. The addition of water must inhibit the formation of ITO crystals, but can strongly promote the formation of In(OH)3 and InOOH, including tin hydroxide. Since In(OH)3 and InOOH was not found in water-free EG system, the transformation of In(OH)3 and InOOH into In2O3 phase must be remarkably slow so that once formed indium hydroxides become final product in water-containing system. The as-prepared particles in BuOH as a solvent consist of irregular shaped nanoparticles of ITO and InOOH. In the solvothermal system with glycol as solvents, direct formation of ITO solid particles was observed starting from amorphous indium hydroxides, In(OH)3 and InOOH phases are not detected as intermediates. In addition, their size with the range from 15 to 40 nm was easily operated with changing conditions, such as aging period and sodium hydroxide concentration. X-ray diffraction measurement and high resolution transmission electron microscopic observation revealed that basically single-crystalline ITO nanoparticles were successfully obtained, and doped tin atoms were uniformly distributed in the nanoparticles.
Microemulsion Synthesis Strategies for ZrW2O8 Precursors
Authors: Vural İrem , Khazeni Nasser , Mavis Bora , Gündüz Güngör , Çolak Üner
Published: October 2010

A zirconium tungstate (ZrW2O8) precursor was synthesized by a novel sol-gel method
with zirconium oxychloride and tungstic acid as the zirconium and tungsten sources, respectively.
Heat treatment at 600oC for 10 hours was adequate to crystallize the precursor. Use of excess
zirconium source and the concentration of hydrochloric acid were found to affect the phase purity
and crystallization temperature of ZrW2O8. Sizes of particles obtained were in submicron range in
the absence of a microemulsion system. On the other hand, using water/oleylamine/hexane reverse
micelle microemulsion technique monodispersed particles with sizes between 10 to 100nm were
obtained. Nanoparticles were then successfully dispersed in a solvent with a carrier polymer to
produce ZrW2O8 nanofibers with electrospinning technique.
Synthesis and Luminescence Properties of Rare-Earth Doped Gadolinium Silicon Oxynitride with Cuspidine Structure
Authors: Mihara S. , Yamaguchi K. , Hintzen H.T. , Delsing A.C.A. , Koda S. , Itatani K.
Published: October 2010

The luminescence properties of rare-earth doped Gd4Si2O7N2 with cuspidine structure were examined. The Gd4Si2O7N2 powder, i.e., a host material, was prepared by mechanically mixing α-Si3N4, SiO2, Gd2O3 and rare-earth oxide (activator) powders (in the stoichiometric ratio Si3N4 : SiO2 : Gd2O3 = 1 : 1: 4) by heating the mixtures at 1700°C for 2 h in N2 atmosphere. When Ce3+ was doped to Gd4Si2O7N2, the emission peak of (Gd0.98Ce0.02)4Si2O7N2 appeared at 457 nm (excitation wavelength: 393 nm) where the blue light was emitted (the relative emission intensity = 0.11 against the standard substance: YAG: Ce3+ (P46-Y3)). When Tb3+ was doped to Gd4Si2O7N2, the emission peak of (Gd0.98Tb0.02)4Si2O7N2 appeared at 545 nm (excitation wavelength: 266 nm) where the green light was emitted (the relative emission intensity = 1.01 against the standard substance: YAG: Ce3+ (P46-Y3)). When both Ce3+ and Tb3+ were co-doped to Gd4Si2O7N2, the emission peak of (Gd0.79Ce0.01Tb0.20)4Si2O7N2 appeared at 545 nm (excitation wavelength: 393 nm) where the greenish yellow light was emitted (the relative emission intensity = 0.95). Such emitting behavior was discussed based upon the energy transfer from Ce3+ and Tb3+.
Panoscopic Assembling of Ceramic Materials for High Performance UV-Ray Shielding Application
Authors: Sato Tsugio , Liu Xiang Wen , Yin Shu
Published: October 2010

The hybrid materials consisting of plate-like potassium lithium titanate (K0.81Li0.27Ti1.73O4)
micro particles coated with calcia-doped ceria (Ce0.8Ca0.2O1.8) nano particles were prepared by the
co-precipitation method and sol-gel method. Broad-spectrum UV-shielding composite materials with
good comfort and low oxidation catalytic activity were successfully synthesized. The comfort when
applied on skin and UV-shielding ability of the composites prepared by the sol-gel method were
superior to those by the co-precipitation method.
Ceramic/Polymeric Hybrids with Reduced Coefficients of Thermal Expansion
Authors: Chen Cheng Gang , Hoos Kevin H. , Chen Ming Yung
Published: October 2010

The mismatch of the coefficient of the thermal expansion (CTE) is one of the main
causes of crack initiation and delamination for carbon fiber-reinforced polymer hybrids and
metal/polymer hybrid materials. In this research, a negative CTE ceramic material (zirconium
tungstate) was incorporated with a thermoset polymer (bismaleimide) resulting in a ~40%
reduction in CTE and a significant improvement in thermal stability. The morphology showed
good dispersion of the zirconium tungstate particles within the bismaleimide. Comparisons of
the experimental CTE values with the rule-of-mixture and the analytical micromechanical
models will be discussed.
Dimension- and Direction-Controlled Gold Nanorods Deposited in Ordered Mesoporous Silica
Authors: Kawamura G. , Hayashi Ikuo , Fitrah Rahmat Ali , Muto Hiroyuki , Hamagami Junichi , Matsuda Atsunori
Published: October 2010

Gold nanorods (GNRs) were deposited in ordered mesoporous silica SBA-15 by a liquid-phase synthesis. The X-ray diffraction pattern of GNRs-deposited SBA-15 (GNRs/SBA-15) confirmed that the mesoporous structure of the SBA-15 was maintained even after depositing GNRs in the SBA-15 pores. Laser irradiation and heat treatment for GNRs/SBA-15 were carried out to check the effect on the GNRs morphology alteration. These treatments were found to shorten the length of the GNRs in SBA-15, leading to a blue shift of the surface plasmon resonance wavelength of the GNRs. Especially, heat treatment at high temperatures, e.g. at 500 °C, showed unique result that the inner wall of SBA-15 was collapsed by the overgrowth of gold nanoparticles.
Simulation of Gasless Combustion of Mechanically Activated Solid Powder Mixtures
Authors: Rashkovskiy Sergey
Published: October 2010

The direct 3D method of numerical simulation of gasless combustion of mechanically
activated solid powder mixtures is developed. The method under consideration falls into three
stages. On the first stage, a simulation of mixture structure is performed. An analysis of the structure
obtained in simulations is carried out. On the second stage, the thermal conductivity of solid powder
mixture is calculated. On the third stage of simulation, the ignition and combustion of each particle
of the mixture is considered with taking into account of heat exchange between contacting particles.
The results of numerical simulations are represented dynamically and compared with the
experimental data, obtained by high-speed digital recording of mechanically activated SHS systems
combustion.
Macrokinetics for Macrostructure Forming of a Product in Self-Propagating High-Temperature Synthesis
Authors: Prokofiev Vadim , Smolyakov Victor
Published: October 2010

A heterogeneous model for ignition and combustion of cylindrical free-gas samples with a gas-permeable and impermeable surface, including the description of structural and phase transformations is formulated. The effective method for numerical model research, taking into account a zonal structure of combustion wave is offered. Dynamics of porous structure forming of products from a stage of ignition up to the steady mode of exothermal reaction front propagation is considered. The calculated stationary combustion rate and elongation of a burned specimen versus its diameter, particle size of a fusible component, initial porosity and pressure of inert gas are received. Experimental data are qualitatively compared with calculated ones. The change in characteristics of combustion wave in a non-stationary mode is analyzed. The structural oscillations resulting in lamination of a porous specimen in a zone of synthesis products in a self-oscillatory combustion mode are found out. The factors, which are the reason for structural oscillations occurrence are determined. Modeling for mechanical compression of a sample shows that a stabilizing effect on the process of combustion consists of additional compensation of loosening forces.
Carbon Combustion Synthesis of Ceramic Oxide Nanopowders
Authors: Martirosyan Karen S.
Published: October 2010

The rapidly growing market demand for nanoparticles calls for cost-effective and environmentally friendly technologies for their large-scale production. We developed a new, simple, economical and energy efficient synthesis of nanostructured complex oxides from inexpensive reactant mixtures, referred to as Carbon Combustion Synthesis of Oxides (CCSO). In CCSO the exothermic oxidation of carbon nanoparticles generates a steep thermal reaction wave that propagates through the solid reactant mixture converting it to the desired complex oxide product. CCSO is a modified form of SHS that maintains the advantages of SHS and circumvents some of its disadvantages. Specifically, it enables a more economical synthesis of complex oxides. The carbon used in CCSO is not incorporated in the product and is emitted from the sample as a CO2. A large gas emission provides a convective cooling mechanism trough the sample that significant reduces local temperature and prevents product partial melting and particles growth. CCSO does not require use of expensive fuel reactants and complex equipment and can be scaled up for continuous mass production. This paper reviewed the recent progress in the synthesis of advanced complex oxides nanoparticles by using carbon combustion process.
Composites Produced by SHS Method – Current Development and Future Trends
Authors: Lis Jerzy , Kata Dariusz , Bućko Mirosław M. , Chlubny Leszek , Zientara Dariusz
Published: October 2010

Basic stages of progress in composite materials, prepared by SHS method, from a scientific approach to a promising and rapidly developing applications are discussed in this paper. The systematic review of different forms of composites prepared directly by SHS or by SHS-origin precursors is presented. Powders are usually the starting material for manufacturing of ceramic and a lot of attention has been paid to find new routes for synthesis powders in form of nano or micro particles. The present work is aimed at efficient and convenient powder processing by SHS as an important target for future composites technology. The use of SHS may bring a considerable development in ceramic technology, by enabling a manufacturing of sinterable, high-purity nano or micro powders. It can be demonstrated in different ceramic systems explored by the authors and coworkers using SHS e.g. (a) Si-C-N, (b) Al-O-N as well as (c) Ti-Si-C-N. Rapid combustion conditions were successfully used to manufacturing composite powders and nanopowders suitable for preparing multiphase composite materials having controlled properties.
Fabrication of Functionally Graded ZTA Ceramics Using a Novel Combination of Freeze Casting and Electrophoretic Deposition
Authors: Preiss Annemarie , Su Bo , Collins Simon , Ellison Peter
Published: October 2010

Functionally graded zirconia toughened alumina (ZTA) ceramics have been fabricated from aqueous
suspension with an open porous and aligned lamellae structure on one side and a dense layer on the
other side. A novel combination of two processes has been merged to achieve such graded structures,
i.e. unidirectional freeze casting and electrophoretic deposition (EPD). A custom-designed apparatus
has been built in which a controlled double side cooling has been realized in conjunction with the
possibility to introduce an electric field over the ceramic slurry prior to the freezing process. A square
wave pulsed DC voltage has been used in the EPD process in order to avoid electrolysis of water.
Suitable duty cycle of applied pulse voltage could gain bubble-free deposition. The thickness of the
dense layer is controlled by tuning voltage, duty of cycle, pulse width and deposition time. It was
shown that thicknesses up to 500μm could be achieved. The microstructure of the porous part is
controlled by adjusting the temperature during the freezing process. Using temperatures between -1 and
-25°C the channel width changed from 220 to 40μm, respectively.
Fabrication of Porous Intermetallic Thick Films by Metallic Powder-Liquid Reaction
Authors: Ohmi Tatsuya , Iguchi Manabu
Published: October 2010

We introduce the concept of functional microchannel lining. As an example, we describe
the composition and structure of a Ni-Al intermetallic layer lining the inner wall of the microchannel
produced by a powder-metallurgical process utilizing microscopic reactive infiltration and/or
diffusion. The Ni-Al lining layer is a thick film consists of multiple sub-layers and has a peculiar
porous structure, in which long and thin micropores had grown along the thickness direction of the
film. In our experiment, a nickel-powder compact containing shaped aluminum wire was sintered at
temperatures between the melting points of nickel and aluminum. Molten aluminum migrated into the
surrounding nickel powder and reacted with nickel, and thus a microchannel and a Ni-Al
intermetallic lining layer were produced. In this process, nickel powder composed the device body,
and the aluminum wire gave the shape of the microchannel and act as the aluminum source for the
lining layer. Metallographical examinations revealed that both aluminum concentration and voidage
in the Ni-Al lining layer show a graded distribution along the thickness direction of the layer. Such a
porous structure is appropriate for a catalyst support used for high-temperature reactions.
Highly Porous Hydroxyapatite Ceramics for Engineering Applicatios
Authors: Ivankovic Hrvoje , Orlic Sebastijan , Kranzelic Dajana , Tkalcec Emilija
Published: October 2010

Highly porous hydroxyapatite (Ca10(PO4)6(OH)2, HA) was prepared through
hydrothermal (HT) transformation of aragonitic cuttlefish bones (Seppia Officinalis L. Adriatic Sea)
in the temperature range from 140°C to 220°C for 20 minutes to 48 hours. Mechanism of
hydrothermal transformation of bones was investigated by DTA/TG analyzer coupled online with
FTIR spectrometric gas cell equipment (DTA-TG-EGA-FTIR analysis), X-ray diffraction analysis
(XRD) and scanning electron microscopy (SEM). DTA-TG-EGA-FTIR analysis have shown the
release of CO2 at about 400°C, 680°C and 990°C. The first release could be attributed to organics
not completely removed from the heat treated bones, and the second release to decomposition of
unconverted aragonite, whereas, the third one could be attributed to CO3
2– groups incorporated in
the structure of HA. The interconnecting porous morphology of the starting material (aragonite)
was maintained during the HT treatment. The formation of dandelion-like HA spheres with
diameter from 3 to 8 μm were observed, which further transformed into nanoplates and nanorods
with an average diameter of about 200-300 nm and an average length of about 8-10 μm.
Spark Plasma Sintering of Boron Carbide and Effects of Various Additives on Sintering and Material Properties
Authors: Çelik Yusuf , Göller G. , Onüralp Yücel , Şahin Filiz Çinar
Published: October 2010

The aim of this study was to produce dense and mechanically strong boron carbide ceramics with the help of different oxide additives. Physical properties of two different grades of pure boron carbide powders were analysed and sintered by Spark Plasma Sintering method. Starting powders were prepared by ball milling with the addition of 5 wt. % Y2O3, Al2O3, SiO2 and Y2O3 + Al2O3. In the sintering step, powder mixtures were sintered by SPS method in round-shaped graphite dies under 50 MPa for 5 minutes in the range of 1700-1800oC. In the characterization step, sintered sample compositions and microstructures were characterized by XRD and SEM analysis respectively. The hardness values were measured under 1000 g load and the density values were measured with Archimedes' principle. The fracture toughness analysis were also carried out.
Finite Element Modeling of Thermal Stress in ITER Prototype Optical Windows and its Influencing Parameters
Authors: Jacobs Marijke , Van Oost Guido , Degrieck Joris , De Baere Ives , Goussarov Andrei , Massaut Vincent
Published: October 2010

Glass-metal joints are needed for the optical windows in ITER to perform diagnostics. These joints must be leak tight for the safety (presence of tritium in ITER) and to preserve the vacuum. They must also withstand the ITER environment: temperatures around 250 °C and neutron fluxes of 109 n/cm2.s. At the moment, little information is available about glass-metal joints suitable for ITER. Therefore, we set-up a 2D elastic model of prototype Al diffusion bonded optical windows using Abaqus code to model temperature effects on the windows. With this model we analyzed the influence of different parameters like the joint area and the braze thickness on the mechanical properties of the joint. Calculations of the thermal stress created by a temperature field of 150 °C (normal ITER temperature) showed that the Al-bond is the weakest part of the window. To find a way of reducing the thermal stress, the influence of some parameters has been studied. In particular, a specific thickness of the Al layer can result in a minimum of stress in the Al bond while the joint area and the thickness of the glass have only a small influence on the stress in the windows. The calculations allowed to propose an optimized design for the windows prototypes.
Study on the Development of Resource-Saving High Performance Slurry - Polishing/CMP for Glass Substrates in a Radical Polishing Environment, Using Manganese Oxide Slurry as an Alternative for Ceria Slurry
Authors: Doi Toshiro K. , Yamazaki Tsutomu , Kurokawa Syuhei , Umezaki Yoji , Ohnishi Osamu , Akagami Yoichi , Yamaguchi Yasuhide , Kishii Sadahiro
Published: October 2010

While investigating polishing mechanism of glass substrates with ceria abrasives (CeO2), we found its oxidizing properties worked effectively for the polishing. This finding has inspired us to speculate about the possibility of the manganese oxide abrasives as an alternative for ceria as they also have oxidizing properties. Therefore, focusing on the valence of the manganese, we have experimentally manufactured MnO, MnO2, Mn2O3 and Mn3O4 abrasives, and conducted a comparison study of the characteristics obtained with ceria slurry and manganese oxide slurries. As a result, the surface roughness of below Ra 0.8nm obtained with Mn2O3 slurry was found better than that with the conventional ceria slurry, on top of which, its removal rate was as good as or equal to that of ceria. Using a novel, closed type CMP (Chemical Mechanical Polishing) machine, we conducted another glass polishing experiment with ceria and manganese oxide slurries. The inside of the CMP machine was filled with high-pressure gases such as oxygen, air and nitrogen and kept at 500kPa to make the polishing environment radical. Through this experiment, we found an effective polishing method for high-quality surface. The removal rates were several times better than that of the conventional polishing performed in an open CMP machine.
Influence of Hydrofluoric Acid Concentration and pH on Corrosion of Porous Multi-Oxide Engineering Ceramics
Authors: Mannila Marju , Häkkinen Antti
Published: October 2010

The object of the research was to compare the corrosion resistance of three types of multioxide
technical ceramics in hydrofluoric acid containing aqueous media according to a full factorial
experimental plan with pH and fluoride ion concentration as variables. The samples were a silicon
carbide doped aluminum silicate material, and two membrane coated aluminum silicates with one
containing a membrane on both sides of the ceramic plate. The substrates contained more additives
on alumina, while the membrane coats were of higher grade aluminum oxide. The samples were
shaken in containers for up to two weeks, and their remaining hardness and weight losses were
measured. Daily samples drawn from the liquid phase were analyzed for dissolved components.
With respect to all measured properties, fluoride concentration affected the materials more
detrimentally than alterations in pH.