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Investigation of fracture porosity as the basis for developing a concrete recycling process using microwave heating
No full textL objet de cette thèse porte sur le développement de technologies efficaces pour le recyclage du béton. Le béton est le plus utilisé des matériaux conçus par l homme, et par voie de conséquence, sa fabrication consomme plus de ressources naturelles que n importe quelle autre industrie. Le béton est responsable de 7% des émissions anthropiques de CO2, la moitié provenant de la décarbonatation du calcaire. Compte-tenu des quantités de matières utilisées et de déchets produits, le recyclage du béton est un enjeu environnemental majeur et une priorité grandissante. Le principal défi au développement et à la mise en oeuvre d un procédé de recyclage du béton concerne la difficulté à séparer ses constituants, les graviers et la pâte de ciment. Le chauffage microonde est un candidat idéal pour parvenir à ce résultat, de par sa capacité à chauffer sélectivement les différentes phases d un matériau multiphasique, induisant ainsi des fractures aux interfaces entre phases et conduisant à leur libération. Les effets du chauffage microonde sur le béton ont donc été étudiés dans cette thèse avec l objectif de conclure quant au bien-fondé de développer un procédé de recyclage qui intègre les microondes. Les effets ont été mesurés par des analyses classiques d échelle macroscopique qui ont mis en évidence une corrélation significative entre le chauffage, l augmentation de porosité et la diminution des propriétés mécaniques du béton. Pour mieux comprendre les changements mesurés à une échelle macroscopique, une technique d analyse locale d images de la texture du béton, basé sur la microscopie électronique, a été développée. L analyse locale des changes induits par le chauffage du béton a révélé la présence d une porosité de fractures, qui a permis d expliquer les changements observés des propriétés du béton les plus pertinentes vis-à-vis du recyclage. L analyse de la texture du béton soumis au chauffage par microondes a mis en évidence la formation de deux réseaux de fractures dans la pâte de ciment, dont le développement est dicté par les conditions du chauffage microonde. Les propriétés texturales de ces réseaux de fractures ont été corrélées directement aux variations des propriétés macroscopiques du béton, ainsi qu à la libération des agrégats. L analyse texturale a montré que la croissance de la fracture à l interface entre les agrégats et la pâte de ciment survient durant les premiers instants du chauffage, et que la libération des agrégats dans le béton, appelée libération texturale, est significativement plus grande que la libération mesurée après fracture du béton par impact. Cette observation a démontré l importance de choisir un mode de fragmentation capable de tirer parti de la fracture sélective des interfaces agrégat-ciment. De plus, le travail réalisé a établi qu il existe des relations de causalité entre les variations de la porosité de fractures présente dans le béton et les propriétés du béton les plus significatives pour son recyclage, révelant ainsi la possibilité de concevoir un procédé de valorisation des déchets de béton en manipulant la texture du béton. En établissant que le chauffage microonde permet de modifier la porosité de fractures du béton, ce travail conclut que le chauffage du béton par microondes est une technologie prometteuse pour concevoir un procédé de recyclage du béton. Au-delà du seul objectif du recyclage du béton, la démonstration de l existence de relations de causalité entre les propriétés de texture du béton et les critères de performance associés à sa fragmentation ouvre des perspectives nouvelles pour analyser et concevoir des procédés de broyage des minerais.This thesis is concerned with the development of efficient concrete recycling technology. Concrete is the most used manufactured material on the planet and as a consequence uses more natural resources than any other industry and is responsible for 7% of the world s carbon dioxide production, 50% of that originating from the decarbonisation of limestone. Given the magnitude of materials used and the waste produced the recycling of concrete would be a major environmental boon and should be made a priority. The main obstacle to the development and implementation of a concrete recycling process is the necessity of separating concrete components, aggregate and cement paste before recycling. Microwave heating stands as an ideal candidate due to its capacity to selectively heat different phases in a multiphase material, thus producing phase boundary fracture and increasing the liberation of the component phases. The effects of microwave heating on concrete samples were investigated with the intent of concluding on the possibility of deriving a microwave-based recycling process for concrete. The effects were measured using standard macroscopic techniques and found a strong correlation between heating, increased porosity and decreased mechanical strength for concrete. In order to better understand the changes measured at the macroscopic scale, a dedicated image analysis technique was developed using electron microscopy to investigate local microscopic changes in concrete texture. Local investigation of the changes of heat treated concrete identified the presence of fracture porosity, which has significant explanatory power for observed changes in concrete properties most relevant to recycling. Textural analysis of concrete subjected to microwave heating showed the growth of two different networks of fractures throughout the cement paste matrix, whose development is associated with the microwave settings. These textural fracture properties correspond directly to the observed changes in mechanical properties as well as the observed liberation of aggregate particles. Textural analysis shows that phase boundary fracture growth occurs rapidly in the early stages of microwave treatment and that the absolute value of textural liberation is significantly higher than that of physical liberation. This highlights the importance of choosing an appropriate comminution method to make efficient use of phase boundary fracture. Moreover, the work established causal relationships between variations in fracture porosity and changes in properties of concrete most relevant to recycling, revealing the possibility of designing a concrete waste beneficiation process through manipulating concrete texture. Since microwave heating was found to be able to manipulate the form taken by the fracture porosity, this work concludes that microwave heating of concrete is a promising technology for designing a concrete recycling scheme. Moreover, through demonstration of causal links between textural properties and processing performance criteria, this work opens the possibility of an alternative approach for analysing and designing comminution process for minerals.TOULOUSE-INP (315552154) / SudocSudocFranceF
„Gold Value“ Offer to Science and Research in Slovakia – is presented by the NISPEZ project and related activities
No full text„Data is the new gold“, Neelie Kroes, Vice-President of the European Commission responsible for the Digital Agenda
The national project activities are aimed at direct support to research and development (R and D) in Slovakia at national level and in long-term horizon. To provide access to a wide offer of world electronic information resources (EIR) is the most important activity. Access to EIR creates a part of a model of completely centralized providing of access to EIR as well as other activities serving to their effective usage. Creating a system for centralized access, search, use and administration of EIR for R and D is the second important project activity.
The third and the same important part of the offer to science and research in Slovakia is represented by building of SciDAP – a central bibliographic database and portal access to the Slovak EIR for research and development. The Slovak scientific and professional journals including open access journals and grey literature documents are concerned. The SciDAP represents a tool to process documents which would be kept for a long time in the institutional repository of SC STI digital documents.
These three activities create a part of the NISPEZ (National Information System to Promote Research and Development in Slovakia – Access to Electronic Information Resources and the Slovak Centre of Scientific and Technical Information is the NISPEZ project solver.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
Federal GL System Input Flow Analysis
No full textThe procedures of collecting, processing and disseminating information on research and development (RandD) reports and theses in Russia are specified by the federal-level grey literature (GL) information system introduced into production use at the Centre of Information Technologies and Systems of Executive State Authorities (abbreviated in Russian as CITIS). The continuity of input document flow is secured by the federal law “On the obligatory copy of documents”. The quantity of arriving documents is important from both theoretical and practical points of view: it reflects the scientific activity of academic community and an executive discipline of scientists; it determines the distribution of workload over time and the completeness of the federal collection. In the paper the system’s input flow analysis is presented based on statistical records of many years. Numerical data in relative and absolute values are given.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
Industrial Philology: Problems and techniques of data and archives preservation for future generations
No full textInstitute of Computational Linguistics in its fifty-year history has accumulated a wide variety of texts and corpora that have been stored in various formats and record layouts. Today, the memory of the procedures and codes of the past is still documented and the people who worked there are in service, we must thus plan a recovery strategy that maintains digital preservation and reuse. For example, one can cite texts in Latin and ancient Greek, which required a complicated system of encoding if we think that in the 60s-70s punch cards with a limited set of characters available were used. This part of the work has already been addressed and equivalence tables were created, so that a full performance can be obtained, even in a non-Latin alphabet, using Unicode encoding. The problems related to text handling are mainly character encodings, based on different operating systems used over the years, the formats of the documents and the indexing system. Differences in the handling of text at different times, and content problems are among the most common. It often happens that textual materials produced in or recovered from a project of the past do not have a standard format, but are the expression both of technology and of the research needs at that time.
For this reason it was decided to study of a system for the realization of procedures for transcoding the characters (from EBCDIC, passing by ASCII, to arrive at Unicode) and for indexing and treatment of any type of texts.
Consequently, for a correct operation of materials recovery was made a standardization procedure of the format of the texts. This allows the disclosure and consultation with any system, open source or proprietary, while fully respecting the rights of the texts that are taken into consideration. It remains to be seen what course to take to preserve the ancient procedures in programming languages for which printouts of processing still exist: can they be preserved or should they be dropped? Can they be considered a form of "industrial archeology"?
The answer to these questions may result from a comparison of opinions that the people of Grey is perhaps the most qualified to do.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
BDSP: a unique initiative to archive and disseminate French grey literature on public health
No full textBDSP (Public Health Databank) is a network of institutions initiated 20 years ago by the French ministry of health. Its aim is to collect and provide access to documents on public health topics, with specific attention to grey literature published in French.
40 organizations participate in this open and collaborative network, including the stakeholders of the French health system and from other French-speaking countries. It is managed by a team of 4 members of the EHESP School of Public Health.
The network produces a multiservice portal which includes a bibliographic database with more than 470,000 records and 64,000 fulltext documents online. It also offers a multilingual glossary and a thesaurus in public health. The website receives about 3000 visits per day.
BDSP is a unique product by its “construction”, its contents and its scope. Its flexible organization has allowed for many adaptations and extensions over the past 20 years, aiming to cover all fields on public health.
The bibliographic database offers access to an important number of grey documents published by the main French organizations involved in public health, research units or government agencies, at both a national and regional level. The documents include expert’s reports, summary reports, policies, theses and dissertations.
Participation in the BDSP network allows its members to archive their grey publications and data, to increase their visibility, to share current awareness tasks and exchange bibliographic records or documents as well as best practices. Working in a network further helps to deal with obstacles in managing grey literature such as insufficient recognition of the documents compared to journal articles, difficulties to obtain authorizations for the dissemination (in particular for government agencies) and to keep up with the rapid evolution of knowledge.
At present the network explores ways to extend its cooperation with other French speaking countries and to share grey literature in French.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
Internet et information santé (enquête auprès des propriétaires d'animaux de compagnie)
No full textLYON1-BU Santé (693882101) / SudocSudocFranceF
Le rôle de l'acide rétinoïque dans le traitement de la leucémie promyélocttaire aigüe
No full textSTRASBOURG ILLKIRCH-Pharmacie (672182101) / SudocSudocFranceF
Le poids influence-t-il la posologie du Doripenem? (Une étude de pharmacocinétique chez le patient obèse en choc septique)
No full textObjectif: Une antibiothérapie précoce et adaptée est indispensable au traitement des épisodes septiques. Le Doripenem a peu été étudié chez l'obèse en situation critique alors que l'obésité el la sévérité sont toutes deux des situations modifiant les paramètres phannacocinétiques. Les objectifs de celte étude sont 1) de comparer la phannacocinétique du Doripenem chez l'obèse et le non obèse en sepsis sévère ou choc septique et 2) de détenniner une posologie optimale pour ces deux populations. Méthodes: Les patients obèses (indice de masse corporelle>35kg/m2) et non obèses (indice de masse corporelle =40% de la durée du traitement avec une concentration sérique en Doripenem supérieure à une concentration minimale inhibitrice de 4mg/mL. Résultats: Onze patients obèses et 13 non obèses ont été inclus, pour un total de 261 prélèvements sanguins. Aucune différence n'a été trouvée entre les groupes concemant la durée de traitement passée avec une concentration sérique en Doripenem supérieure à 4mg/mL (les durées médianes étaient de 85% et 60% chez les obèses et les non obèses (p=0,7)). Le volume de distribution à l'équilibre et la clairance n'étaient pas influencés par le poids. Les simulations de Monte Carlo démontraient une exposition insuffisante au Doripenem avec une posologie de 0,5g par 8h si une concentration minimale inhibitrice de 4mg/mL était visée, et suggéraient comme adéquate la posologie de 1g par 8h. Conclusion: Il n'a été trouvé aucun effet du poids sur la pharmacocinétique du Doripenem dans les situations de sepsis sévère et choc sept ique chez le patient obèse. Doubler la posologie de 0,5g à 1g par 8h pourrait diminuer le taux d 'exposition insuflisante au Doripenem chez les patients obèses et non obèsesObjective: Sepsis needs early and adequate antibacterial drug exposure to ensure trealment success. Obesity and critical illness modify pharmacokinetics (PK) of drugs but doripenem PKs is poorly studied in obese critically ill patients. The aims of the present study were 1) to compare PKs of Doripenem in obese and non obese patients wilh severe sepsis or septic shock and 2) to determine optimal dosing. Methods: Critically ill severe obese (body mass index >=35kg/m2) and non obese patients (body mass index =40% of the dosing interval with a doripenem serun concentration over a 4mg/mL minimum inhibitory concentration. Results: Eleven severe obese and 13 non obese patients were enrolled, for a total of 261 blood samples. We found no difference betweell groups in fractional time with a doripenem serum concentration above 4mg/mL (median time was 85% and 60% in obese and non obese (p=0.7)) There was no effect of weight on volume of distribution or doripenem clearance. Monte Carlo simulations showed insuflicient drug exposure with 0.5g q8h if the targeted minimum inhibitory concentration was 4mg/mL, but suggested 1g q8h was an adequate dosing. Conclusion: There was no evidence of the effect of weight on Doripenem pharmcokinetics when used for severe sepsis or septic shock. Doubling the rccommended dose from 0.5g to 1g q8h could lower insufficient drug exposure in both obese and non obese patientsMONTPELLIER-BU Médecine UPM (341722108) / SudocSudocFranceF
Les problèmes dus aux piqûres d'hyménoptères en officine
No full textLes hyménoptères tels que les abeilles, guêpes, ou frelons sont souvent sources de dangers lorsqu'ils se sentent agressés. Les piqûres d'hyménoptères sont responsables de plusieurs décès par an (10 à 20 morts par an) en France et plusieurs centaines en Europe. Ces réactions peuvent être bénignes, avec une réaction locale ou plus étendue, mais peuvent aussi être mortelle lorsqu'elles impliquent, une toxicité massive du venin ou encore le système immunitaire, entrainant ainsi un choc anaphylactique. Pour cela de nouvelles méthodes sont mises en place pour guérir mais surtout prévenir ces accidents potentiellement mortels ; entre autre via l'immunothérapie au venin. Cette thèse constitue un réel support pour notre rôle en officine, afin de savoir détecter les situations à risque, et de pouvoir conseiller et traiter de façon adéquate.CHATENAY M.-PARIS 11-BU Pharma. (920192101) / SudocSudocFranceF
Dysfonctions sexuelles et médicaments de substitution aux opiacés
No full textBESANCON-BU Médecine pharmacie (250562102) / SudocSudocFranceF