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1	Materiálový efekt při interakcích jaderné palivo - chladící médium: Strukturní analýza úlomků parní exploze a mechanismus solidifikace / Material effect in nuclear Fuel - Coolant interaction: Structural characterization of the steam explosion debris and solidification mechanism Tyrpekl, Václav January 2012 (has links) Thesis Abstract This thesis has been performed under co-tutelle supervision between Charles University in Prague (Czech Republic) and Strasbourg University (France). It also profited from the background and cooperation of Institute of Inorganic Chemistry Academy of Science of the Czech Republic and French Commission for Atomic and Alternative energies (CEA Cadarache, France). Results of the work contribute to the OECD/NEA project Serena 2 (Program on Steam Explosion Resolution for Nuclear Applications). Presented thesis can be classed in the scientific field of nuclear safety and material science. It is aimed on the so-called "molten nuclear Fuel - Coolant Interaction" (FCI) that belongs among the recent issues of the nuclear reactor severe accident R&D. During the nuclear reactor melt down accident the melted reactor load can interact with the coolant (light water). This interaction can be located inside the vessel or outside in the case of vessel break-up. These two scenarios are commonly called in- and ex-vessel FCI and they differ in the conditions such as initial pressure of the system, water sub-cooling etc. The Molten fuel - coolant interaction can progress into thermal detonation called also "steam explosion" that can challenge the reactor or containment integrity. Recent experiments have shown that...
2	A Theory Of Dropwise Condensation Tekin, Hasan Fehmi 01 December 2005 (has links) (PDF) A Theory of Dropwise Condensation TJ Energy Conservation 163.26-163.5
3	Effet matériaux lors de l'interaction corium-eau : analyse structurale des débris d'une explosition vapeur et mécanismes de solidification / Material effect in the fuel – coolant interaction : structural characterization of the steam explosion debris and solidification mechanism Tyrpekl, Vaclav 26 June 2012 (has links) Ce travail a été réalisé en cotutelle entre l’Université Charles à Prague (République Tchèque) et l'Université de Strasbourg (France). Il a également profité d’une coopération entre l'Institut de Chimie Inorganique de l'Académie des Sciences de République Tchèque et le Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA, Cadarache, France). Les résultats des travaux ont contribué au projet OCDE / AEN Serena 2 (Programme portant sur l’étude des effets d'une explosion de vapeur dans un réacteur nucléaire à eau). La thèse présentée se situe dans le domaine de la sûreté nucléaire et de la science des matériaux. Elle traite de l’Interaction Combustible-Réfrigérant (ICR, ou FCI en anglais pour Fuel-Coolant Interaction) susceptible d’intervenir lors d’un accident grave de réacteur nucléaire et actuellement à l’étude dans les programme de R&D. Au cours d’un accident de fusion d’un coeur de réacteur, les matériaux fondus peuvent interagir avec le liquide de refroidissement (eau légère), aussi appelé réfrigérant. Cette interaction peut se produire à l'intérieur de la cuve ou, en cas de rupture de celle-ci, à l'extérieur. Ces deux scénarios sont couramment appelés Interaction Combustible-Réfrigérant en- et hors- cuve et se distinguent de par les conditions du réacteur lors de l’accident : pression du système, degré de sous refroidissement de l’eau, etc. L'interaction entre le combustible fondu et le liquide de refroidissement peut évoluer vers une détonation thermique appelée «explosion de vapeur» qui peut endommager le réacteur, voire compromettre l'intégrité du confinement. Des expériences récentes ont montré que la composition du combustible a un effet majeur sur l’apparition et le rendement d’une telle explosion. En particulier, des comportements différents ont été observés entre un matériau simulant, l'alumine, qui explose très facilement, et diverses compositions de corium prototypique (80 m. % UO2, 20% m.% ZrO2). Cet «effet matériau» a suscité un intérêt nouveau pour les analyses post-expériences des débris issus de l’ICR afin de déterminer les mécanismes qui interviennent au cours de ces phénomènes extrêmement rapides. La thèse est organisée en neuf chapitres. Le chapitre 1 constitue une introduction générale et présente le contexte d’un accident grave d’un réacteur nucléaire. Quelques exemples d’accidents graves (Three Miles Island 1979, Tchernobyl 1986 et Fukushima 2011) sont brièvement abordés. Le chapitre 2 résume les aspects théoriques de l'interaction combustible-réfrigérant. Il est divisé en quatre parties correspondant aux quatre étapes généralement rencontrées lors du mécanisme d’ICR i) Prémélange - le combustible fondu, versé dans l'eau, se fragmente en gouttelettes grossières qui s’isolent d’un film de vapeur. ii) Déclenchement – le film de vapeur entourant les gouttes de combustible est déstabilisé, permettant ainsi la fragmentation fine du combustible. iii) Propagation - la fragmentation du combustible se propage à l’ensemble du prémélange, augmentant ainsi la surface de contact entre le combustible fondu et l’eau. Ceci conduit à une production intense de vapeur à grande échelle. iv) Expansion (explosion) - l'énergie thermique transférée du combustible à l'eau est transformée en travail mécanique de la vapeur.[...] / This work has been performed under co-tutelle supervision between Charles University in Prague (Czech Republic) and Strasbourg University (France). It also profited from the background and cooperation of Institute of Inorganic Chemistry Academy of Science of the Czech Republic and French Commission for Atomic and Alternative energies (CEA Cadarache). Results of the work contribute to the OECD/NEA project Serena 2 (Program on Steam Explosion Resolution for Nuclear Applications).Presented thesis can be classed in the scientific field of nuclear safety and material science. It is aimed on the socalled “molten nuclear Fuel – Coolant Interaction” (FCI) that belongs among the recent issues of the nuclear reactorsevere accident R&D. During the nuclear reactor melt down accident the melted reactor load can interact with the coolant (light water). This interaction can be located inside the vessel or outside in the case of vessel break-up. These two scenarios are commonly called in- and ex-vessel FCI and they differ in the conditions such as initial pressure of the system, water sub-cooling etc. The Molten fuel – coolant interaction can progress into thermal detonation called “steam explosion” that can challenge the reactor or containment integrity.Recent experiments have shown that the melt composition has a major effect on the occurrence and yield of such explosion. In particular, different behaviors have been observed between simulant material (alumina), which has important explosion efficiency, and some prototypic corium compositions (80 w. % UO2, 20% w. % ZrO2). This “material effect” has launched a new interest in the post-test analyses of FCI debris in order to estimate the processes occurring during these extremely rapid phenomena. The thesis is organized in nine chapters. The chapter 1 gives the general introduction and context of the nuclear reactor accident. Major nuclear accidents (Three Miles Island 1979, Chernobyl 1986 and Fukushima 2011) are briefly described. The chapter 2 summarizes the theoretical aspects of the fuel – coolant interaction. It is divided in four thematic fields according to the FCI progression. In general, FCI has four stages: i) Premixing – hot melt is poured in water and fragmented in coarse droplets surrounded by steam filmii) Triggering – steam film around melt droplets is destabilized allowing fine fragmentation iii) Propagation – the fine fragmentation propagate through the premixture increasing the melt – water interface area, which leads to large steam production iv) Expansion (explosion) – Thermal energy transferred from the melt to water is changed into mechanical workof the steam.The chapter 3 summarizes the research conducted in different experimental facilities using nonradioactive simulant or radioactive prototypic materials. The chapter 4 shows the results of thermodynamic calculations, by which thepossible chemici reactions between melts and water/steam at high temperatures were modeled. Second part presentsthe results of 1D calculations of radiation heat transfer from FCI materials to water/steam. The chapter 5 describes the material analyses of non-radioactive simulant debris coming from MISTEE experimental research program (KTH, Sweden) and PREMIX, ECO facilities (FZK, Germany). The chapters 6 to 8 describe the material analyses of radioactive prototypic debris coming from KROTOS research program (CEA, France). The KROTOS KS2 test used melt composition 70 w. % UO2 and 30 w. % ZrO2, the KS4 test 80 w. % UO2 and 20 w. % ZrO2, the last KS5 test used suboxidized melt 80.1 w. % UO2 and 11.4 w. % ZrO2 and 8.5 w. % metallic Zr. The chapter 9 concludes the work and presents future perspectives. Interaction combustible – refrigerant Effet des matériaux Calcul thermodynamique, Analyse de l'état solide Nuclear Reactor Severe Accident Fuel – Coolant Interaction Material effect Thermodynamic modeling Solid-state characterization 539.7
4	From the "rising tide" to solidarity: disrupting dominant crisis discourses in dementia social policy in neoliberal times MacLeod, Suzanne 26 March 2014 (has links) As a social worker practising in long-term residential care for people living with dementia, I am alarmed by discourses in the media and health policy that construct persons living with dementia and their health care needs as a threatening “rising tide” or crisis. I am particularly concerned about the material effects such dominant discourses, and the values they uphold, might have on the collective provision of care and support for our elderly citizens in the present neoliberal economic and political context of health care. To better understand how dominant discourses about dementia work at this time when Canada’s population is aging and the number of persons living with dementia is anticipated to increase, I have rooted my thesis in poststructural methodology. My research method is a discourse analysis, which draws on Foucault’s archaeological and genealogical concepts, to examine two contemporary health policy documents related to dementia care – one national and one provincial. I also incorporate some poetic representation – or found poetry – to write up my findings. While deconstructing and disrupting taken for granted dominant crisis discourses on dementia in health policy, my research also makes space for alternative constructions to support discursive and health policy possibilities in solidarity with persons living with dementia so that they may thrive. / Graduate / 0452 / 0680 / 0351 / macsuz@shaw.ca social determinants of health social exclusion crisis discourse Alzheimer's Alzheimer Society of Canada Suzanne MacLeod Susan Strega Donna Jeffery poststructural poststructuralism admission to long-term care funding for long-term care acute care aging demographic BC Psychogeriatric Association biomedical British Columbia Canada Health Act collective social responsibility competition corporate profit corporatization deresponsibilization elder friendly elderly citizens family caregivers Foucault found poetry genealogy of power knowledge incompetent Ministry of Health moral economics pharmaceutical bed blocker stigmatized tsunami absent-person action plan aging population alternative discourse apocalyptic demography appropriate archaeology archaeology of knowledge archaeological British Columbia burden Canada caregiver charity charitable collective collective car community community care condition of possibility conditions of possibility corporate counter-discourse dementia dementia care dementia policy dementia social policy dependent depoliticize discourse discourse analysis disruptive discourse economic burden economics economy elder emergency epidemic exclusion fear-monger Foucauldian found poem genealogy genealogical health authority health care health care staff health care system health policy document healthy lifestyle home and community care homogenization homogenize hospital imaginaries imaginary incapable individual responsibility individualism knowledge long-term care material effect materiality of discourse media moral panic national strategy neoliberal neoliberalism neoliberal rationality not prepared object objectification other person-centered people living with dementia person living with dementia persons living with dementia person with dementia poem poetic representation poetry policy policies political politics power power knowledge power relations private privatize privatization productivity of dominant discourse public health care residential care resistance responsibility responsibilization rising tide safety net shift costs to caregivers responsibility social policy imaginary social well-being social work social worker solidarity specialized stakeholder state stigma subject matter expert taxpayer threat unprepared unproductive voluntary volunteer wait time wave social policy
5	From the "rising tide" to solidarity: disrupting dominant crisis discourses in dementia social policy in neoliberal times MacLeod, Suzanne 26 March 2014 (has links) As a social worker practising in long-term residential care for people living with dementia, I am alarmed by discourses in the media and health policy that construct persons living with dementia and their health care needs as a threatening “rising tide” or crisis. I am particularly concerned about the material effects such dominant discourses, and the values they uphold, might have on the collective provision of care and support for our elderly citizens in the present neoliberal economic and political context of health care. To better understand how dominant discourses about dementia work at this time when Canada’s population is aging and the number of persons living with dementia is anticipated to increase, I have rooted my thesis in poststructural methodology. My research method is a discourse analysis, which draws on Foucault’s archaeological and genealogical concepts, to examine two contemporary health policy documents related to dementia care – one national and one provincial. I also incorporate some poetic representation – or found poetry – to write up my findings. While deconstructing and disrupting taken for granted dominant crisis discourses on dementia in health policy, my research also makes space for alternative constructions to support discursive and health policy possibilities in solidarity with persons living with dementia so that they may thrive. / Graduate / 0452 / 0680 / 0351 / macsuz@shaw.ca social determinants of health social exclusion crisis discourse Alzheimer's Alzheimer Society of Canada Suzanne MacLeod Susan Strega Donna Jeffery poststructural poststructuralism admission to long-term care funding for long-term care acute care aging demographic BC Psychogeriatric Association biomedical British Columbia Canada Health Act collective social responsibility competition corporate profit corporatization deresponsibilization elder friendly elderly citizens family caregivers Foucault found poetry genealogy of power knowledge incompetent Ministry of Health moral economics pharmaceutical bed blocker stigmatized tsunami absent-person action plan aging population alternative discourse apocalyptic demography appropriate archaeology archaeology of knowledge archaeological British Columbia burden Canada caregiver charity charitable collective collective car community community care condition of possibility conditions of possibility corporate counter-discourse dementia dementia care dementia policy dementia social policy dependent depoliticize discourse discourse analysis disruptive discourse economic burden economics economy elder emergency epidemic exclusion fear-monger Foucauldian found poem genealogy genealogical health authority health care health care staff health care system health policy document healthy lifestyle home and community care homogenization homogenize hospital imaginaries imaginary incapable individual responsibility individualism knowledge long-term care material effect materiality of discourse media moral panic national strategy neoliberal neoliberalism neoliberal rationality not prepared object objectification other person-centered people living with dementia person living with dementia persons living with dementia person with dementia poem poetic representation poetry policy policies political politics power power knowledge power relations private privatize privatization productivity of dominant discourse public health care residential care resistance responsibility responsibilization rising tide safety net shift costs to caregivers responsibility social policy imaginary social well-being social work social worker solidarity specialized stakeholder state stigma subject matter expert taxpayer threat unprepared unproductive voluntary volunteer wait time wave social policy

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