Dissertations / Theses: '4IR'

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Wessels, Carina Helena. "To IOT or not IOT : a critical analysis of the key legal considerations applicable in internet of things of implementations in the mining industry." Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60113.

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The research introduces the fourth industrial revolution philosophically, exploring the application of innovation and automation in broad terms and the Internet of Things (IoT) specifically within the mining industry. It explains the business and societal motivation for such interventions, highlighting some of the key benefits. It further explores the inadvertent risks, some of which have already manifested in mining applications and others which can be inferred from other industrial and social applications. A critical analysis is conducted of the application of the South African Mine Health and Safety Act and Regulations on such applications in the mining environment, as well as considering key other pieces of South African legislation. A comparative analysis with Australian legislation confirms that Western Australia has recognised the need for regulation and have started regulating, primarily mining automation, at least. Through these analyses it is established that a legislative vacuum exists, despite the general application of many requirements in relation to safety considerations during the utilisation of IoT applications. The paper concludes by recommending collaboration between the Department of Mineral Resources and the Chamber of Mines to seek ways to lead legislative and regulatory developments in this space in order to enable the sustainability of the South African mining industry. In particular, the research suggests the emphasis should be to legally encourage and permit the implementation of IoT solutions in the mining industry in as many instances as reasonably possible, whilst consecutively addressing the new and emerging risks created through such.
Mini Dissertation (LLM)--University of Pretoria, 2016.
Public Law
LLM
Unrestricted

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Bin, Nasir Muhammad Akash, and Abubakar Ismail Sada. "Stimulating Internationalization through digitalization : Digital competence in Swedish manufacturing SMEs." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387820.

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Digital competence used to be a confusing concept, until recently when some researchers coined a comprehensive definition of digital competence and formulated a conceptual framework in an SME context. However, the framework was only at a conceptual level and required to be tested with the empirics of a qualitative or quantitative study. By an abductive qualitative approach, this research explored existing theories on digital competence and formulated a new digital competence framework in Swedish manufacturing SME perspective. Moreover, with cross-sectional study design, this research explored the role of digital competence in the internationalization process of six Swedish manufacturing firms, which is unprecedented in academic literature. Our findings indicate that digital competence is an evolving concept which develops gradually with technological advancements and requires a combination of three integral components: i) Digital technologies (basic and advanced level digitalization), ii) Automation of organizational processes, iii) Human resources who have the latest digital skills and are duly motivated to use these skills. This research affirms that after attaining digital competence Swedish manufacturing SMEs can sustain a competitive advantage in their international markets and it successfully facilitates in the firm’s internationalization process.
Digital kompetens brukade vara ett förvirrande koncept fram till nyligen när vissa forskare utarbetade en omfattande definition av digital kompetens och formulerade en konceptuell ram i ett små och medelstora sammanhang. Ramverket var dock endast på en konceptuell nivå och krävdes att testas med empiriken i en kvalitativ eller kvantitativ studie. Genom ett abduktivt kvalitativt tillvägagångssätt undersökte denna forskning befintliga teorier om digital kompetens och formulerade en ny digital kompetensram inom svenskt tillverkningspolitiskt perspektiv. Vidare undersökte denna undersökning rollen som digital kompetens i internationaliseringsprocessen av sex svenska tillverkningsföretag, vilket är enastående i den akademiska litteraturen. Våra resultat tyder på att digital kompetens är ett utvecklande koncept som utvecklas gradvis med tekniska framsteg och kräver en kombination av tre integrerade komponenter: i) Digital teknik (grundläggande och avancerad digitalisering), ii) Automatisering av organisationsprocesser, iii) Personal som har de senaste digitala färdigheterna och är vederbörligen motiverade att använda dessa färdigheter. Den här forskningen bekräftar att svenska tillverkare små och medelstora företag efter att ha uppnått digital kompetens kan upprätthålla en konkurrensfördel på sina internationella marknader och framgångsrikt underlättar företagets internationaliseringsprocess.

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Qhola, Lipolelo. "The medicinal chemistry of Cyclo (D-PHE-4I-PRO) and Cyclo (L-PHE-4I-PRO)." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1011619.

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Cyclic dipeptides have been widely used as pharmaceutical agents due to their favourable properties and the fact that they are more stable and membrane permeable than their linear analogues. These characteristics make cyclic dipeptides attractive to protein-based drug developers (Martins & Carvalho, 2007). In this research study, the method of Milne et al. (1992) was used to synthesize the protected linear dipeptide esters. This was followed by boiling the unprotected, linear dipeptide esters under reflux in an oil bath (Sec-butanol: toluene (4:1)). This method gave good yields and pure cyclic dipeptides. Scanning electron microscopy, thermal analysis, X-ray powder diffraction and differential scanning calorimetry were used for evaluation of the physiochemical properties of the cyclic dipeptides. High-performance liquid chromatography and thin layer chromatography were used to determine the purity of the cyclic dipeptides. The structures of the cyclic dipeptides were elucidated using infrared spectroscopy, mass spectrometry, nuclear magnetic resonance spectroscopy and molecular modeling and computational chemistry. The aim of the study was to determine the possible therapeutic activity of cyclo(D-Phe-4I-Pro) and cyclo(L-Phe-4I-Pro) with regard to antimicrobial, anticancer, antidiabetes and haematological effects. Both cyclic dipeptides showed a significant growth inhibition of Gram-positive, Gram-negative and fungal microorganisms in the antimicrobial study. Anticancer studies showed that both cyclic dipeptides caused growth inhibition of the MCF-7, HT-29 and HeLa cancer cell lines. Both cyclic dipeptides showed no antidiabetic activity. Haematological studies revealed that both cyclic dipeptides caused a significant effect on the clotting time and platelet aggregation. They caused an increase in clotting time and also inhibited platelet aggregation.

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McGillvray, Patrick J. "Integration of Systems Management Departments 0TR, 4TR, and 8TR token ring local area networks." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA304520.

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Solomon, Daniel Maurice. "Effects of Mission Overloads on Fatigue Crack Growth in Ti-6Al-2Sn-4Zr-2Mo." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1532083676103601.

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Neumann, Ulf Peter. "Untersuchungen zur Effizienz einer CTLA-4Ig Therapie in Kombination mit adoptivem Zelltransfer zur Vermeidung von Abstoßungsreaktionen im Modell der orthotopen Rattenlebertransplantation." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2003. http://dx.doi.org/10.18452/13865.

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Einleitung: CTLA-4Ig blockiert CD28-vermittelte co-stimulatorische Signale und inhibiert kompetitiv in vitro und in vivo immunologische Reaktionen. Der signifikante immunsuppressive Effekt von CTLA4-IG konnte in verschiedenen tierexperimentellen Untersuchungen zur Entwicklung von Toleranz nach Organtransplantation aufgezeigt werden. Allerdings waren die Ergebnisse nach CTLA-4Ig Therapie in den nachfolgenden Untersuchungen variable und ein Großteil der transplantierten Organe wurde letztendlich abgestoßen. Neuere Studien zeigen das die Effizienz der CTLA-4Ig Therapie von dem Zeitpunkt der Gabe abhängen. Weiterhin gibt es Anhalte dafür, daß dieser Effekt durch spenderabgeleitete Transfusionen noch verstärkt werden kann. Für uns stellte sich daher die Frage ob durch die Kombination von CTLA-4IG und Applikation spenderabgeleiteter Splenozyten ein additiver immunsuppressiver Effekt zu erreichen ist und untersuchten dies im Modell der Rattenlebertransplantation (ORLT). Methodik: Wir führten Rattenlebertransplantationen (ORLT) im arterialisierten, voll allogenen Modell Da (RT1a) auf Lew (RT1l) in Standardtechnik durch. Die Ratten erhielten in verschiedenen Gruppen vor/nach der Transplantation CTLA-4Ig oder die Kombination von CTLA-4Ig mit spenderabgeleiteten oder unspezifischen Milzzellen. Ergebnisse: Bei der Vorbehandlung der Empfänger, entweder mit spenderabgeleiteten Zellen oder CTLA-4Ig, ließ sich eine Verbesserung des Transplantatüberlebens, aber keine Langzeitakzeptanz des Transplantates erreichen. Erst die Kombinationstherapie vor der Transplantation gewährleistete ein langfristiges Organüberleben ohne Zeichen für chronische Rejektionen nach mehr als 150 Tagen. Die Therapie mit spenderabgeleiteten Zellen am Tag der Transplantation oder verzögert nach 4 Tagen nach Transplantation veränderte die Überlebenszahlen nicht. Die verzögerte postoperative Therapie mit CTLA-4Ig, wie sie auch von anderen Gruppen durchgeführt wurde, resultierte in unseren Versuchen in einem verlängertem Überleben, führte aber nur bei 2/7 Tieren zur langfristigen Transplantatakzeptanz. Die zusätzliche Applikation nicht abgeleiteter Milzzellen verbesserte die Ergebnisse nicht signifikant. Transplantatakzeptanz bei allen Tieren ließ sich wiederum nur durch die Kombination spenderabgeleiteter Zellen und CTLA-4Ig erreichen. Spenderabgeleiteter Mikrochimärismus trat bei allen Tieren, also auch bei Kontrolltieren trotz ablaufender Abstoßung am 6. POD nach ORLT auf. Am 12. POD zeigten tolerante Gruppen noch spenderabgeleitete Zellen, wohingegen diese bei abstoßenden Gruppen nicht mehr nachweisbar waren. Im Langzeitverlauf waren diese spenderabgeleiteten Zellen auch in toleranten Tieren nur noch vereinzelt nachzuweisen. Eine Verschiebung der Zytokinantwort von TH1- Richtung TH2-Zytokinen konnte bei langfristig überlebenden Tieren nicht aufgezeigt werden. Im Gegenteil, die TH1-Antwort mit INF-g und IL-12b war bei toleranten, kombiniert mit CTLA-4Ig und adoptivem Zelltransfer behandelten Ratten früher und stärker ausgeprägt, aber schneller wieder rückläufig als bei unbehandelten Kontrollen. Dies galt nicht für IL-2, das in allen Gruppen, die mit CTLA-4Ig behandelt wurden, stark unterdrückt war. Langfristig überlebende Tiere zeigten mehr als 150 Tage nach ORLT nahezu keine Expression dieser TH1-Zytokine mehr, wohingegen IL-4 deutlich exprimiert wurde. Dies spricht gegen eine ausschließliche Verschiebung der Zytokinantwort nach TH2 und betont die Bedeutung von TH1-Zytokinen in der initialen Phase der Toleranzentwicklung. In toleranten Tieren mit adoptivem Zelltransfer zeigte sich im Vergleich zu abstoßenden Tieren eine stärkere Ausprägung von Apoptose in den Transplantaten, die zeitlich parallel zu der mRNA-Expression der TH1-Zytokine verlief. Dies läßt darauf schließen, daß Apoptose aktivierter T-Zellen der Mechanismus ist, der die additiven Effekte der CTLA-4Ig-Behandlung und des adoptiven Zelltransfers vermittelt. Die CTLA4-Ig Behandlung verhindert effektiv Abstoßungsepisoden nach ORLT. Die Effizienz der Behandlung kann durch die Applikation von spenderabgeleiteten Zellen noch signifikant verbessert werden. Hierbei spielt die Herunterregulation von IL-2 und Hochregulierung von INF-g eine maßgebliche Rolle, wohingegen der spenderabgeleitete Chimärismus von nachgeordneter Rolle zu sein scheint. Parallel zu dem Nachweis von IFN-g finden sich mehr apoptotische Zellen am Tag 6 in den Transplantaten der später toleranten Ratten, verglichen mit den abstoßenden Kontrolltieren. Dies weist in diesem Modell, im Gegensatz zu anderen Theorien, auf einen immunaktivierten Mechanismus mit nachfolgender Apoptose aktivierter Lymphozyten hin
Blockage of co-stimulatory CD28-mediated signals by CTLA4-Ig inhibits in vitro and in vivo immune responses. However, in recent trials monotherapy with CTLA4-Ig failed to introduce long-term survival in several animal transplant models. The study was conducted to investigate the effectiveness of CTLA-4Ig treatment with additional application of donor splenocytes in preventing rejection and improving graft function in rat liver allografts. DA rats (RT1a) were used as donors and Lew (RT1l) rats as recipients in an orthotopic liver transplantation model (ORLT). Recipients were divided in 3 groups depending on the start of treatment: The first group was treated prior to transplantation with CTLA-4Ig (0.5 mg i.p.) alone or in combination with donor derived or donor unspecific 2.5 x 108 splenocytes. The second group was treated simultaneously at transplantation with CTLA-4Ig or received no further treatment and served as controls. The third group received an ORLT and was treated postoperatively on day 3 and 4 with CTLA4-Ig alone or in combination with donor derived or unspecific spleen cells. Only the combination of CTLA-4Ig and donor derived cells pre- or postoperatively led to a 100% graft survival in the long-term. The treatment with CTLA-4Ig alone at each time point led to prolonged graft survival but not to a long-term graft survival. The additional administration of donor unspecific cells could improve these results, however, the differences were not significantly different between these groups. All rats without any treatment died within 12 days after ORLT. When treating the rats with donor derived spleen cells prior to transplantation the survival was significantly prolonged. The application of donor unspecific cells alone pre- and postoperatively had no effect on the survival rates. Microscopic and macroscopic studies of the liver demonstrated no signs of ongoing rejection after 150 days in rats treated with the combination of CTLA4-Ig and donor derived cells. All other long term survivors demonstrated signs of chronic rejection with bile duct loss. Immunohistological staining for DA specific surface antigen demonstrated donor specific chimerism with no predominance in any group. In the early postoperative course, the expression of IL-2 in liver specimen was significantly reduced in all groups receiving CTLA-4Ig. In contrast to this the tolerant rats surviving long-term showed a marked expression of IFN-g in the early course after ORLT. Additionally, these rats showed on day 6 after ORLT more apoptosis in the liver graft specimens compared to rejecting controls. CTLA4-Ig treatment is highly effective in rat liver transplantation and ensure long term survival. Pretransplant or delayed treatment with CTLA4-Ig alone prolongs survival but does not introduce long term tolerance. The effectiveness of the treatment can be markedly improved by the additional application of donor derived cells. The downregulation of IL-2 is mainly involved in the development of tolerance whereas detection of donor specific chimerism is not correlated to the development of tolerance in our study. Additionally an activation induced cell death via IFN-g may be involved in the tolerance induction. Although the mechanisms are still not completely understood immunomodulation by adaptive cell transfer and costimulatory blockage is an interesting and promising option for the future of clinical liver transplantation.

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Mindak, Mary. "An analysis of firms impacted by FASB Interpretation No. 46R — Consolidation of variable interest entities." Cincinnati, Ohio : University of Cincinnati, 2009. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1241117373.

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Thesis (Ph.D.)--University of Cincinnati, 2009.
Advisor: P.K. Sen. Title from electronic thesis title page (viewed July 27, 2009). Keywords: Fin 46R; consolidation; disclosure; variable interest entities. Includes abstract. Includes bibliographical references.

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Robayna, Matthew S. "When incentives aren't enough : challenges in Chapter 40R Massachusetts Smart Growth Zoning Overlay District Act implementation." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118237.

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Thesis: M.C.P., Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 59-61).
The Greater Boston area has some of the highest housing costs in the country, a trend which has only intensified through the nation's recovery from the recent global financial crisis. Greater Boston has a fragmented municipal system, with individual cities and towns controlling their own land use regulations. This fragmentation has led to a system where cities and towns regulate land use in an uncoordinated manner, leaving the entire region with a shortage of housing and raising housing costs. In 2004, the Commonwealth of Massachusetts enacted Chapter 40R, the Smart Growth Overly District Act, to incentivize communities to implement zoning districts that allow dense housing by right. To date, very few communities in Greater Boston have enacted Chapter 40R districts, and once those districts are enacted, very few of the newly-zoned units are built. This thesis seeks to explore the causes behind these phenomena. Communities in the region are loath to implement 40R districts because of an aversion to growth, in particular multifamily development. Misconceptions about program requirements may also prevent town planners from using 40R as a planning tool for their communities. Developers don't often utilize 40R as a permitting mechanism because it is riskier to implement than Chapter 40B permitting. Even when 40R districts are established, units are not always built because of market conditions or land availability. While 40R has produced successful developments across the state, this report calls into question whether an incentive-based development policy is sufficient to deal with the region's current housing shortage.
by Matthew S. Robayna.
M.C.P.

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Guo, Yina. "Microstructure and texture characterisation of linear friction welding of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-6Mo." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4386/.

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Linear friction welding (LFW) of two α - β titanium alloys, Ti-6Al-4V (Ti64) and Ti-6Al-2Sn-4Zr-6Mo (Ti6246) was studied, focusing on micro-hardness measurement, microstructure and texture characterisation. It has been found that in the as-welded condition Ti6246 has lower micro-hardness values in the weld region than in the base material, while for Ti64 the weld region is harder. The change in hardness is greatly related to the microstructures formed after welding. In cnetre weld zone (CWZ), in the autogenous Ti6246 weld, the microstructure consists of fine β grains with needle shape orthorhombic α″. In the autogenous Ti64 weld, relatively large acicular martensitic α′ phase was found. A very strong texture component, where the basal pole is concentrated in the sample normal direction and one of the {11 20}α poles is concentrated in the oscillation direction, is identified in both the CWZ and thermo-mechanically affected zone. Comparison between the α texture and the β texture suggests that the strong texture component T is the consequence of the deformation β texture developed at high temperature and the preferred variant selection during the β→α transformation. The texture was found to have significant influence on the fracture toughness of the weld region.

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Wang, Yuqi M. C. P. Massachusetts Institute of Technology. "State zoning legislation and local adaptation : an evaluation on the implementation of Massachusetts Chapter 40R Smart Growth Legislation." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90113.

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Thesis: M.C.P., Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 85-88).
The Smart Growth Zoning Overlay District Act (M.G.L. Chapter 40R, the Legislation) was issued in March 2005 with the mission to substantially increase the supply of housing, especially for low- and moderate-income households, and to incentivize Smart Growth land development patterns. Municipalities participate in this program by voluntarily adopting a Smart Growth zoning district in their local zoning ordinance/by-laws which allows dense housing development as-of-right. Participating municipalities will receive a Zoning Incentive Payment upon creating the district, based on the additional number of housing units allowed as-of-right under 40R compared with base zoning, and a Density Bonus Payment for each new unit built in the district. They will also have priority when competing for other state discretionary subsidies. As of December 2013, thirty-three 40R Smart Growth Overlay Districts (40R District) have been approved in thirty-two Massachusetts communities, with an aggregate area of 1,436 acres, and a total number of 12,350 Future Zoned Units; another three 40R districts are pending or under review. Ten 40R Districts have projects (or project phases) that have been built and put into use. This study aims to give a diagnostic evaluation on the current and potential effectiveness of the Legislation in achieving the goals of facilitating quality housing production and promoting Smart Growth. The evaluation is set in the context of housing development and land planning in Massachusetts, which is also the background of the Legislation, and based on four 40R cases from four different municipalities, each of which has adopted local zoning ordinance/by-laws, created a 40R district, and completed development under 40R. In each case, the Smart Growth qualities of the development are evaluated against a set of qualitative criteria developed from the Smart Growth principles outlined in the Legislation, with reference to prevailing Smart Growth standards used in the profession and feedback from 40R's implementers. The role of 40R in leading to these development results are then analyzed, which highlights the prospect of 40R's application and impact in the future. The main conclusions are: Generally speaking, 40R plays an important role in helping communities achieve their own vision of Smart Growth and housing production by resolving the site, financial, or other development obstacles that are imbedded in the local development context and base zoning. This success is achieved through incentive-based stakeholder cooperation, an indispensable part of the entire 40R zoning and (project) permitting process. Also, the Legislation provides a very general and broad description of Smart Growth principles, and therefore each community may interpret and define Smart Growth standards according to local needs. Being flexible, adaptable and context-sensitive is key to creating opportunities where various stakeholders find common interests in establishing partnerships around 40R. Moreover, when used appropriately, 40R as a zoning tool, could potentially have larger impacts in facilitating Smart Growth and housing production over a longer period than other policies that are based on a single project. However, in some cases, being flexible and sensitive to local context seems to have gone too far, and as a result, offset some of the benefits promised by 40R, such as housing being in close proximity to jobs and amenities, streamlining the permitting process, etc. The reasons for this drawback come from both 40R itself and the context in which 40R operates. Some requirements of 40R are too vague and allow a zoning district or project to gain 40R status and incentive payments even though it fails to meet most of the Smart Growth principles outlined in the Legislation. The recent amendment to the 40R Regulations tries to solve this problem by setting more straightforward and explicit requirements; the results of these changes remain to be seen. In terms of barriers, there are general concerns about and oppositions to Smart Growth from the neighborhood, local government, and development community, who tend to use their power as stakeholders to resist Smart Growth policies. They are particularly resistant to a zoning policy like 40R for fear that it will allow Smart Growth types of development as-of-right. The home-rule tradition and a lack of regional planning for Smart Growth land use further weaken the legislative and regulatory foundations of 40R. 40R has limited leverage to overcome these context barriers; its effectiveness in facilitating Smart Growth will remain confined by the development context at least in the near future. Key words: Smart Growth, Zoning, Chapter 40R, Massachusetts.
by Yuqi Wang.
M.C.P.

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Viana, Felipe Albernaz. "Estudo diastereosseletivo da reação de Ugi (U-5C-4CR), mediadas por sais metálicos ambientalmente amigáveis, CuBr e LiClO4." reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/16519.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, 2014.
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As reações multicomponentes (RMCs) são reações de grande importância em Síntese Orgânica onde várias ligações C-C e C-X são formadas de forma eficiente, a partir da mistura de 3 ou mais reagentes, gerando um produto complexo contendo a maioria dos átomos dos reagentes. Dentre os diferentes tipos de RMCs, as reações multicomponentes com isocianetos (RMCIs) têm se destacado bastante nos últimos anos, especialmente as reações de Ugi e Passerini. Nesse sentido, esse trabalho traz um estudo metodológico e diastereosseletivo da reação de Ugi do tipo U-5C-4CR utilizando os aminoácidos naturais: (L)-valina, (L)-isoleucina e (L)-fenilalanina; dois isocianetos aquirais: terc-butilisocianeto e isocianoacetato de etila; um isocianeto quiral: o (S)-metil-benzil isocianeto; e vários aldeídos aromáticos e alifáticos, em metanol, na presença de dois ácidos de Lewis ambientalmente amigáveis, o LiClO4 e CuBr. Os 33 amino ésteres secundários sintetizados foram obtidos em rendimentos que variaram de 16-95% com diastereosseletividades de até 14,9:1, em favor do diastereoisômero (S,S). Os estudos mostraram que, na maioria dos casos , o LiClO4 apresentou melhores rendimentos e diastereosseletividades que o CuBr. Foi observado ainda que o isocianeto contendo uma carbonila  ao grupo isonitrila, o isocianoacetato de etila, aumenta significativamente a diastereosseletividade dos produtos de Ugi. Isso acontece devido a uma possível coordenação do grupo carbonila (C=O) com o complexo metálico da imina, gerado in situ, o que favorece o ataque preferencial do isocianeto à face Si no estado de transição, levando a uma boa seletividade. A reação de hidrólise de um dos produtos de Ugi (amino éster) foi realizada levando à formação de um possível aminoácido não natural com grande potencial para aplicação como organocatalisador em reações orgânicas. ______________________________________________________________________________ ABSTRACT
Multicomponent reactions (MCR’s) are reactions of great importance in Organic Synthesis where several C-C and C-X bonds are efficiently created, from the mixture of 3 or more reagents, furnishing a complex compound containing most of the reagents atoms. Among the different kinds of MCR’s, multicomponent reactions with isocyanides (IMCR’s) have excelled in recent years, particularly Ugi and Passerini reactions. In this context, this work brings a methodological and diastereoseletive study of a Ugi reaction type, U-5C-4CR, using natural amino acids: (L)-valine, (L)-isoleucine and (L)-phenylalanine; two achiral isocianydes: tert-butyl isocyanide and ethyl isocyanoacetate; a chiral isocyanide: (S)-methylbenzyl isocyanide; and several aromatic and aliphatic aldehydes, dissolved in methanol, in the presence of two environment-friendly Lewis acid, LiClO4 and CuBr. Those 33 secondary aminoesters synthesized were obtained in yelds ranging from 16% to 95% with diastereoselectivities up to 14,9:1, in favor of diastereoisomer (S,S). The studies present that, in most cases, LiClO4 showed better yields and diastereoseletivities tha CuBr. It was noted that the isocyanide containing an α carbonyl to the isonitrile group, the ethyl isocyanoacetate, increases significantly the diastereoselectivity of the Ugi results. This happens due to a possible coordination of the carbonyl group (C=O) with the metal complex of the imine, created in situ, which favors the preferencial attack of the isocyanide at Si face in the transition state, leading to a good selectivity. The hydrolysis reaction of one of the Ugi products (amino ester) was carried out leading to the formation of a possible unnatural amino acid with grat potential for application as organocatalyst in organic reactions.

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Edström, Rickard, and Oscar Elkan. "En filmmarknad i förändring." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-234055.

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Den pågående processen mot en ökad användning av digitala tjänster har inte minst påverkat filmmarknaden. Digitala tjänster för filmkonsumtion, både illegal och lagliga, utmanar filmmarkadens arbetssätt och struktur, och skapar därmed ett behov av förändring. De illegala tjänsterna har etablerats tidigt och påverkar i hög grad marknaden. Särskilt tydligt är detta för den svenska filmmarknaden, där dessa tjänster används i hög utsträckning. Användningen av digitala tjänster, såväl illegala som lagliga, påverkar inte minst filmkonsumenters attityder och förväntningar på hur tjänster för filmkonsumtion bör fungera. Vanor kring nyttjande av teknik, och kring filmkonsumtion mer generellt är också intressanta att studera för att se vilka framtida förändringar i aktörernas arbetssätt som är motiverade. Studien belyser hur de olika typer av aktörer som utgör filmmarknaden idag arbetar med hänsyn till den rådande situationen, samt de förändringar i detta arbete som betingas av förändrade konsumentattityder. Studien identifierar två tydliga hot mot filmmarknadens rådande affärsmodell: minskade intäkter generellt och ett skift mot minskad konsumtion av ny film. Motiverade arbetssätt för filmmarknaden i stort som identifieras är bland annat att förbättra utbudet i de digitala lagliga tjänsterna, göra dessa tjänster smidigare samt lobba för strängare upphovsrättslagstiftning. Studien tyder vidare på att den filmrelaterade verksamheten inom vissa typer av aktörer kommer att minska och är utdömd på sikt. Dessa typer av aktörer är traditionella filmbutiker samt filmfokuserade logistikbolag. Filmbutikerna kan på lång sikt övergå till att fokusera helt på dagens kringprodukter, medan logistikbolagen kan nyttja sin existerande logistikkompetens för att erbjuda logistiktjänster för andra typer av produkter än film.
The ongoing process towards an increased usage of digital services has affected the movie market. Digital providers for movie consumption, both illegal and legal ones, challenge the functioning and structure of the movie market, and thus create a need for change. The illegal providers have been established a long time ago, and affect the market to a large degree. This is especially significant in the movie market of Sweden, where the usage of the illegal services is high. The usage of digital services, both illegal and legal ones, affects the attitudes and expectations of consumers of movies, with regards to how services for movie consumption ought to function. Consumer habits regarding usage of technology, and regarding movie consumption in general, are also interesting to study, in order to see which future changes in the work of the actors of the movie market are reasonable with regards to changed habits. This study investigates how the different kinds of actors that constitute the movie market are working in relation to the current situation. It also presents the possible future changes in this work that reasonably follow from the changed consumer attitudes and expectations. The study identifies two clear threats to the current business model of the movie market: generally decreased revenues, and a shift towards a decreased consumption of new movies. A few changes in the overall work of the movie market are identified as motivated. These are e.g. providing an increased offering of diversity of content in the new legal providers, making these services more convenient to use, and lobbying for stronger copyright laws. The study also indicates that the movie-related business within certain kinds of actors will lessen in importance, and is doomed in the longer term. These kinds of actors are traditional movie rental stores, as well as movie-focused logistics companies. The rental stores can make a long-term transition of their business towards focusing completely on products that are currently defined as complementary. The logistics companies can use their existing logistics expertise to offer logistics services for other kinds of products.

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Pederson, Robert. "The microstructures of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-6Mo and their relationship to processing and properties /." Luleå, 2004. http://epubl.luth.se/1402-1544/2004/19.

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Kirilova, Kremena [Verfasser]. "Effizienz einer Vorbehandlung mit CTLA-4Ig und adoptivem Zelltransfer zur Vermeidung akuter Abstoßungen nach Lebertransplantation im Rattenmodell / Kremena Kirilova." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2012. http://d-nb.info/106409807X/34.

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15

Martins, André Fernandes [UNESP]. "Caracterização do aço inoxidável ASTM A743 CA6NM e do seu revestimento de WC-10Co-4Cr aspergido termicamente por HVOF." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/127963.

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A tecnologia de aplicação de revestimento por aspersão térmica de chama oxicombustível de alta velocidade, mais conhecida pelo seu termo em inglês HVOF (high velocity oxigen fuel), apresenta o melhor custo benefício entre as técnicas de aspersão térmica, além de permitir uma ampla gama de revestimentos possíveis de serem aspergidos. Por essas razões, esse é o processo mais utilizado no recobrimento de pás de turbinas fabricadas para usinas hidrelétricas, como é o caso das do projeto Santo Antônio localizado no Rio Madeira em Rondônia/Brasil. Este trabalho buscou caracterizar o aço inoxidável martensítico ASTM A743 CA6NM, assim como o revestimento de WC-10Co-4Cr durante as etapas do processo de aspersão térmica por HVOF. Foram feitas medidas de rugosidade, coeficiente de atrito, dureza, molhabilidade, porosidade e espessura de camada do revestimento, além da analise da microestrutura do aço inoxidável. Estas caracterizações foram feitas sobre o substrato usinado, jateado e sobre os revestimentos aspergidos, com espessura de 0,1 e 0,2 mm. Os resultados obtidos apresentam alteração significativa de dureza, com o valor médio elevando de 318 HV, no aço inox, para 1100 HV no revestimento. O coeficiente de atrito inicial foi de 0,2, passando para 0,4 em menos de 500 voltas no aço e 0,8 no revestimento. O caráter hidrofílico foi mantido na superfície do aço e no revestimento. O revestimento apresentou porosidade abaixo de 2% e a rugosidade Ra, em torno, de 4,6 Qm
The high velocity oxygen fuel (HVOF) coating technology, have shown the best results comparing with the related cost and it is able to be spray several coating composition. Due to all these reasons, this is the most used coating process on hydro power plants blades, as it is the case of Santo Antonio project settled in the Madeira river, Rondônia/Brazil. In This research was carried out the martensitic stainless steel characterization ASTM A743 CA6NM, as well as the characterization of the WC-10Co-4Cr coating during the HVOF process. Measurements of roughness, coefficient of friction, hardness, wettability, porosity, coating thickness and microstructure of base metal and coating, by optical microscope, were carried out. These analysis was done on machined stainless steel surface, on blasted surface and on 0,1 and 0,2 mm coating surfaces. The results demonstrate an increase in hardness from 318HV in the stainless steel to 1100HV in the coating. The initial coefficient of friction was 0,2 and raised up to 0,4 after 500 laps on the stainless steel and 0,8 on the coating. The hydrophilic behavior was kept on stainless steel and coating. The coating porosity was below 2% and the Ra roughness around 4,6 Qm

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Diniz, Celso. "Caracterização microestrutural e análise eletroquímica do revestimento de WC-10Co-4Cr, aspergido termicamente por HVOF, em aço inoxidável martensítico." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/153504.

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Aços inoxidáveis martensíticos, contendo 12-13% de cromo, 2-5% de níquel e menos de 0,06% de carbono, vem sendo utilizados desde a década de 60, por exemplo, na fabricação de equipamentos hidráulicos, tais como turbinas, bombas e propulsores. Aços como o ASTM A743 CA-6NM, temperados e revenidos, passam por processos de tratamento de superfície, visando aumentar a resistência à erosão e corrosão, pois devem, operar sob condições de alta agressividade. Dentre as técnicas utilizadas para revestimento de superfície, a aspersão térmica, HVOF (Hight Velocity Oxigen Fuel), é um processo altamente utilizado, por sua viabilidade técnica e econômica. Atualmente, o aço ASTM A743 CA-6NM com revestimento do tipo WC-10Co-4Cr, com espessura em torno de 100 e 200 µm, é o material mais empregado nos diversos equipamentos hidráulicos, tais como: rotores de bombas, pás de turbinas e hélices navais. O conhecimento das características microestruturais do revestimento e de seu comportamento com relação à corrosão são de grande importância na definição dos parâmetros para a realização da aspersão térmica, gerando economia e qualidade do revestimento. Neste trabalho são realizadas análises por microscopia óptica e microscopia eletrônica de varredura com EDS sobre os revestimento aspergido com WC-10Co-4Cr, visando estudar os parâmetros relacionados à porosidade e composição da microestrutura. Além disso, foram realizadas análises da dureza, ao longo de todo o revestimento, visando estabelecer correlação com as análises obtidas por microscopia, e análise eletroquímica com o intuito de compreender o comportamento do revestimento em meio salino NaCl 3,5% ( mm); todas as imagens adquiridas, passaram por processamento digital. Os resultados demonstraram que os revestimentos obtidos com 6 passes (W6) ou 8 passes (W8) apresentaram baixa porosidade, menor que 2%, sendo que os poros medidos no revestimento W6 apresentaram menor diâmetro de Feret e maior circularidade. A análise com durômetro revelou um comportamento similar dos revestimentos, com valores de dureza praticamente idênticos ao longo da espessura das camadas aspergidas. Os ensaios eletroquímicos, mostraram que o substrato apresentou corrosão puntiforme (pite) após imersão por 5, 20 e 30 h, em solução de NaCl 3,5% (mm), resultado típico para este material. Enquanto os revestimentos W6 e W8, que dentro das especificações dos ensaios, apresentaram comportamentos idênticos, nas análises com circuito aberto e curva de polarização, se mostraram revestimentos com proteção contra a corrosão.
Martensitic stainless steels, containing 12-13% chromium, 2-5% nickel and less than 0.06% carbon, have been used since the 1960s, for example, in the manufacture of hydraulic equipment such as turbines, pumps and propellers. The steels ASTM A 743 CA-6NM, in quenched and tempered conditions, undergo surface treatment processes to increase resistance to erosion and corrosion, once they do operate under conditions of high aggressiveness. Among techniques used for surface coating, thermal spraying, HVOF (Hight Velocity Oxigen Fuel), is a highly utilized process, due to its technical and economical viability. Currently, ASTM A743 CA-6NM steel with WC-10Co-4Cr type coating, with a thickness of 100 m and 200 m, is the most used material in the various pieces of equipment, such as: pump rotors, naval blades and propellers. The knowledge of the microstructural characteristics of the coating and its behavior in relation to corrosion are of great importance, in the definition of the parameters for the realization of the thermal spray, generating economy and quality of the coating. In this paper, optical microscopy and scanning electron microscopy with EDS, on WC-10Co-4Cr sputtering coatings were carried out to study the parameters related to the porosity and microstructure composition. In addition, hardness analyses were performed throughout the coating, to establish correlation with microscopic analysis and electrochemical analysis in order to understand the behavior of the coating in saline solution NaCl 3.5% (wt/wt); all images acquired, passed by digital processing images. The results showed that the coatings obtained with 6 passes (W6) or 8 passes (W8) presented low porosity, less than 2%, and the pores measured in the W6 coating presented smaller Feret diameter and greater circularity. Dilution analysis revealed a similar behavior of the coatings, with hardness values practically identical across the thickness of the sprayed layers. The electrochemical tests showed that the substrate presented punctiform corrosion (pite) after 5, 20 and 30h immersion in NaCl solution 3.5% (wt/wt); result for this material. While the W6 and W8 coatings, which presented identical behavior in the open circuit analysis and polarization curve, within the test specifications, corrosion resistant coatings were found.

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Martins, André Fernandes. "Caracterização do aço inoxidável ASTM A743 CA6NM e do seu revestimento de WC-10Co-4Cr aspergido termicamente por HVOF /." Guaratinguetá, 2015. http://hdl.handle.net/11449/127963.

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Orientador: Rogério Pinto Mota
Banca: Konstantin Georgiev Koslov
Banca: Tessie Gouvea da Cruz
Resumo: A tecnologia de aplicação de revestimento por aspersão térmica de chama oxicombustível de alta velocidade, mais conhecida pelo seu termo em inglês HVOF (high velocity oxigen fuel), apresenta o melhor custo benefício entre as técnicas de aspersão térmica, além de permitir uma ampla gama de revestimentos possíveis de serem aspergidos. Por essas razões, esse é o processo mais utilizado no recobrimento de pás de turbinas fabricadas para usinas hidrelétricas, como é o caso das do projeto Santo Antônio localizado no Rio Madeira em Rondônia/Brasil. Este trabalho buscou caracterizar o aço inoxidável martensítico ASTM A743 CA6NM, assim como o revestimento de WC-10Co-4Cr durante as etapas do processo de aspersão térmica por HVOF. Foram feitas medidas de rugosidade, coeficiente de atrito, dureza, molhabilidade, porosidade e espessura de camada do revestimento, além da analise da microestrutura do aço inoxidável. Estas caracterizações foram feitas sobre o substrato usinado, jateado e sobre os revestimentos aspergidos, com espessura de 0,1 e 0,2 mm. Os resultados obtidos apresentam alteração significativa de dureza, com o valor médio elevando de 318 HV, no aço inox, para 1100 HV no revestimento. O coeficiente de atrito inicial foi de 0,2, passando para 0,4 em menos de 500 voltas no aço e 0,8 no revestimento. O caráter hidrofílico foi mantido na superfície do aço e no revestimento. O revestimento apresentou porosidade abaixo de 2% e a rugosidade Ra, em torno, de 4,6 Qm
Abstract: The high velocity oxygen fuel (HVOF) coating technology, have shown the best results comparing with the related cost and it is able to be spray several coating composition. Due to all these reasons, this is the most used coating process on hydro power plants blades, as it is the case of Santo Antonio project settled in the Madeira river, Rondônia/Brazil. In This research was carried out the martensitic stainless steel characterization ASTM A743 CA6NM, as well as the characterization of the WC-10Co-4Cr coating during the HVOF process. Measurements of roughness, coefficient of friction, hardness, wettability, porosity, coating thickness and microstructure of base metal and coating, by optical microscope, were carried out. These analysis was done on machined stainless steel surface, on blasted surface and on 0,1 and 0,2 mm coating surfaces. The results demonstrate an increase in hardness from 318HV in the stainless steel to 1100HV in the coating. The initial coefficient of friction was 0,2 and raised up to 0,4 after 500 laps on the stainless steel and 0,8 on the coating. The hydrophilic behavior was kept on stainless steel and coating. The coating porosity was below 2% and the Ra roughness around 4,6 Qm
Mestre

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Yang, Yang. "Etude de la transformation martensitique et des mécanismes de déformation se produisant dans l’alliage superélastique Ti-24Nb-4Zr-8Sn." Thesis, Rennes, INSA, 2015. http://www.theses.fr/2015ISAR0002/document.

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Les alliages de titane sont actuellement très utilisés comme implants orthopédiques de part leurs bonnes propriétés mécaniques, leur bonne résistance à la corrosion ainsi que leur excellente biocompatibilité. Cependant, l’alliage Ti-6Al-4V qui est le plus utilisé présente un module d'élasticité élevé (110GPa), ce qui peut provoquer le phénomène de « stress shielding » et finalement causer l’échec de l’implantation. De plus, l’utilisation à long terme de ce type d’alliage est remise en question à cause de la présence de certains éléments (Al et V) considérés comme cytotoxiques et/ou allergènes. Les alliages -métastables à base de titane peuvent être des candidats de remplacement intéressants grâce à l’addition d'éléments biocompatibles tel que Nb, Zr et Sn.L'alliage superélastique biocompatible de composition Ti-24Nb-4Zr-8Sn (% massique) a été étudié dans le cadre de cette thèse. Cet alliage montre des propriétés intéressantes telles qu’un bas module d’élasticité, une résistance mécanique élevée et une ductilité relativement importante.Dans ce travail de thèse, différents traitements thermomécaniques ont été réalisés afin d’obtenir des textures cristallographiques différentes. Les influences de changement de texture sur les propriétés mécaniques et la superélasticité ont été ainsi préalablement étudiées. La transformation martensitique a été caractérisée par des essais in situ de diffraction des rayons X sous rayonnement synchrotron (SXRD) pendant une sollicitation mécanique et par analyse mécanique dynamique (DMA) sous différentes contraintes statiques. De plus, les microstructures de déformation ont été observées par EBSD et MET pour caractériser précisément les mécanismes de déformation plastique, en particulier le maclage
Titanium alloys have already been extensively used as orthopedic implants due to the good mechanical properties, corrosion resistance and excellent biocompability. However, the most widely used Ti-6Al-4V alloy exhibits high elastic modulus (110GPa) which would cause the stress shield effect and eventually lead to the implantation failure. Furthermore, elements of Al and V are proved to be toxic for long-term application. Low modulus metastable  titanium alloy can be a suitable candidate through proper addition of non-toxic alloying element such as Nb, Zr and Sn.The present investigated Ti-24Nb-4Zr-8Sn alloy is a new -type metastable alloy potentially interesting for biomedical applications. This alloy displays high strength, low elastic modulus, high ductility, superelastic property and good biocompatibility according to previous investigations.In this work, the as-cold rolled Ti-24Nb-4Zr-8Sn alloy was subjected to different thermo-mechanical treatments in order to introduce different crystallographic texture. Influences of texture change on mechanical properties and superelasticity have been preliminarily studied. Martensitic transformation which is responsible for the superelasticity has been characterized by both in situ synchrotron X-ray diffraction and dynamic mechanical analysis. Moreover, deformed microstructures have been observed by EBSD and TEM to characterize precisely the plastic deformation mechanisms, and particularly the twinning

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Ovadia, Reuben. "Réaction multicomposants pour la synthèse de dimères de PNA ciblant la replication du virus de l'hépatite C." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4098/document.

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Avec plus de 170 millions de personnes infectées, l'infection par le virus de l'hépatite C (VHC) représente une des premières infections virales dans le monde. La recherche et la mise au point de nouvelles molécules, capables de traiter de cette maladie sont donc d'une grande importance. Dans ce contexte et sur la base de résultats préliminaires obtenus avec des dinucléotides phosphoramidates GpC inhibant l'initiation de la réplication par la polymerase NS5B, nous avons conçu des inhibiteurs de seconde génération de type dimère de PNA (Peptide nucleic Acid). Nous présentons dans ce manuscrit la mise au point d'une méthode de synthèse originale de monomères et dimères de PNA, basée sur l'utilisation d'une réaction de Ugi à quatre composants (U-4CR). Cette méthode par U-4CR offre une grande variabilité de structures et séquences (G, A, C, T, U) en un nombre limité d'étapes, de plus la combinaison avec une activation micro-ondes permet d'augmenter l'efficacité et de réduire considérablement les temps de réaction. Cette stratégie a été appliquée en série dimère de PNA et en série chimère PNA-ARN
With more than 170 millions people chronically infected, hepatitis C virus represents one of the major viral infections in the world. The research and development of novel antiviral is hence of great importance. In this context and on the basis of preliminary results obtained with dinucleotide phosphoramidates GpC inhibiting the initiation of replication of the NS5B polymerase, we designed a second generation of inhibitors type PNA dimers (Peptides Nucleic Acid). We describe in this manuscript the development of an original strategy to synthesize PNA monomers and dimers based on the use of the well-known Ugi four component reactions (U-4CR). This method allows a great structural variability in a limited number of steps. More, combining this efficient tool with microwaves irradiations allows an increase of the efficiency and a dramatic acceleration of the reaction time. This strategy was applied in PNA dimers series and PNA-RNA chimera series

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Nagasima, Denis Marcel Pires. "Efeito de remoção eletrolítica para reparo do revestimento de WC-10Co-4Cr aplicado por HVOF em aplicação de desgaste erosivo." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3151/tde-13122018-074434/.

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A operação de uma turbina hidráulica para hidrogeração alocada em um rio com sedimentos pode levar ao desgaste erosivo e, consequentemente, manutenção prematura do componente. Visando mitigar esse problema, em geral, aplicam-se revestimentos que aumentam a vida útil das turbinas, mas não eliminam o desgaste erosivo ocorrido, o que leva à necessidade de reparo do componente. O reparo se inicia com a remoção do revestimento remanescente e reconstituição da geometria por solda, para então, reaplicação de um novo revestimento. Nem sempre as regiões afetadas são grandes, o que possibilitaria a aplicação de um reparo por soldagem e também reparo de revestimento localizado na turbina. O reparo sobre o revestimento pode ser aplicado tanto na recuperação de componentes que sofrem desgaste erosivo, bem como, para consertar problemas ocorridos durante o processo de revestimento anterior. O presente trabalho visa compreender e verificar a possibilidade de reparo em um revestimento de WC-10Co-4Cr executado pelo processo de aspersão térmica HVOF (high velocity oxy fuel), bem como, suas limitações em desgaste erosivo. O estudo foca na preparação sobre um revestimento existente (remoção eletroquímica) e aplicação de uma nova camada. Como avaliação inicial o trabalho considerou o ensaio de desgaste erosivo, onde foi encontrado aumento de 22% na quantidade de material erodido nos corpos de prova com reparo. A observação e comparação dos corpos de prova com e sem reparo, utilizando microscopia eletrônica de varredura (MEV), mostra que a diferença em desgaste está na delaminação entre camadas devido à falha coesiva, a qual pôde ser observada através do ensaio de adesão. A falha coesiva pode ser explicada com base em análise por EDS dos corpos de prova, por intermédio da qual foi verificado um aumento na quantidade de oxigênio e, consequentemente, presença de óxido na preparação superficial por remoção eletroquímica.
The operation of a hydraulic turbine for hydropower generation located in a river with sediments can lead to erosive wear, and, as a consequence, premature maintenance of the component. In order to minimize such problem, coatings are applied to increase turbine lifetime, but they do not eliminate erosive wear, which leads to the necessity of component repair. The repair starts with the removal of the remaining coating and reconstitution of the geometry by welding, and then reapplication of a new coating. The affected regions are not necessarily large, which would allow the application of a localized repair by welding and localized repair by coating. The coating repair can be applied in two situations: recovery of components with erosive wear and to fix problems during coating manufacturing. The present work aims to understand and verify the possibility of repair in a WC-10Co-4Cr coating performed by the thermal spraying HVOF process (high velocity oxy fuel), as well as, its limitations in erosive wear. This study focuses in the preparation of an existing coating (electrochemical removal) and application of new coating layers. The start point was an evaluation using an erosion test rig, which indicated an increase of 22% in material removal for the test samples with repair. Using scanning electron microscope (SEM), the test samples with and without repair were compared and showed a wear difference related to delamination between layers due to cohesive failure, which was also observed in the adhesion test. The cohesive failure can be explained by EDS, where it was found a high content of oxygen in the repaired zones, and, as a consequence, presence of oxide in the surface preparation by electrochemical removal.

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Neumann, Ulf Peter. "Untersuchungen zur Effizienz einer CTLA-4Ig-Therapie in Kombination mit adoptivem Zelltransfer zur Vermeidung von Abstossungsreaktionen im Modell der orthotopen Rattenlebertransplantation." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968763901.

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Ramakrishnan, Gokulakrishnan. "A Study of Thermal Stability of Residual Stresses and Fatigue life of Laser Shock Peened Ti-6Al-2Sn-4Zr-2Mo alloy." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353099593.

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Paninho, Helena Isabel Ferreira. "Discovery IQ 4R: otimização da imagem PET-CT em ambiente clínico." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/18794.

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Mestrado em Tecnologias da Imagem Médica
O recente equipamento da GE Healthcare, o PET/CT Discovery IQ 4R, fornece a maior sensibilidade, o maior campo de visão da indústria e tecnologia de aquisição de duplo canal. Ainda, o algoritmo de reconstrução Q.Clear controla o ruído através de um fator de penalização (β), permite uma convergência efetiva e providencia valores de Standardized Uptake Vaues (SUV) mais precisos. O objetivo deste projeto foi determinar qual o fator de penalização ótimo e parâmetros de aquisição ideais em estudos clínicos. Foram adquiridas imagens com o fantoma de qualidade NEMA IEC, preenchido com uma concentração radioativa de fundo de 5,40 kBq/mL e as esferas com 24,66 kBq/mL. Foram calculados coeficientes de recuperação (CR) e variabilidade de fundo (VF) nas imagens reconstruídas com o algoritmo Q.Clear (β variável entre 150 e 500). Sessenta doentes realizaram estudos PET/CT com 18F-FDG e foram divididos de acordo com a atividade administrada (2, 3 e 4 MBq/kg). As imagens foram adquiridas em list mode e reconstruídas com 30, 60, 90 e 120 segundos, usando um algoritmo standard (VUE Point HD) e o algoritmo Q.Clear. Foram avaliados SUV máximos das lesões, rácios lesão/fundo e as imagens foram revistas visualmente por 2 observadores. Observou-se que os valores de CR e VF diminuem à medida que o fator β aumenta, especialmente em pequenas estruturas. Os valores de SUV máximo diminuem à medida que o fator β aumenta. Os rácios lesão/fundo são mais elevados com o Q.Clear em relação ao algoritmo standard, sem diferenças estatísticas significativas em todos os conjuntos. A avaliação qualitativa mostrou uma concordância reduzida entre os observadores. Os resultados obtidos demonstram que o algoritmo Q.Clear tem um impacto significativo no contraste e quantificação das lesões. O valor ótimo para o fator de penalização β necessita de ser ajustado de acordo com o tipo de estrutura a ser estudada. xii
The up-to-date GE Healthcare scanner, PET-CT Discovery IQ 4R, provides the highest sensitivity, the largest field of view of the industry and dual energy acquisition channel technology. In addition, the algorithm Q.Clear, controls the noise through the use of a penalization factor (β), that allows an effective convergence and provides more consistent measurements of Standardized Uptake Values (SUV). The aim of this project was to determine the optimum penalization factor β of Q.Clear and ideal acquisition parameters in clinical settings. A NEMA IEC Body Phantom, filled with a background activity of 5,40 kBq/mL and spheres with 24,66 kBq/mL was acquired on a PET-CT Discovery IQ 4R and recovery coefficient (RC) and background variability (BV) were determined for images reconstructed with Q.Clear (β 150-500). Sixty patients performing 18F-FDG PET-CT were divided per administered dose (2, 3 and 4 MBq/Kg). The images were acquired in list mode and reconstructed with 30, 60, 90 and 120 seconds using a standard algorithm (VUE Point HD) and Q.Clear. These were evaluated for lesions SUVmax and lesion/background ratios and qualitatively by 2 observers. It has been observed that RC and BV values decrease as the β value increases, especially for smaller structures. SUVmax values decrease as the β value increases. Lesion contrast ratios are higher with Q. Clear when compared with standard algorithm, but with no statistical significant difference for all image reconstruction sets. Qualitative evaluation shows a small agreement between the scores. Results obtained show that Q.Clear has a significant impact in lesion contrast and quantification. The optimum penalization factor of Q. Clear needs to adjusted according to the type of structure being studied. xiv

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Salazar, González Ricardo Andrés. "Preparación, caracterización electroquímica y reactividad de nuevas 1,4-dihidropiridinas-4R-sustituidas." Tesis, Universidad de Chile, 2008. http://www.repositorio.uchile.cl/handle/2250/105160.

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Chaia, Nabil. "Mise au point de revêtements protecteurs pour le gainage du combustible en alliage de vanadium V-4Cr-4Ti destiné aux RNR-Na." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0149/document.

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L’usage de l’alliage de vanadium V-4Cr-4Ti comme matériau de gainage du combustible dans les réacteurs nucléaires à neutrons rapides refroidis au sodium (RNR-Na) représente un intérêt tout à fait particulier de par ses propriétés physico-chimiques attractives à savoir : une bonne compatibilité avec le sodium liquide, une transparence neutronique élevée et de bonnes propriétés mécaniques sous irradiation. Toutefois, la dissolution de l’oxygène dans le vanadium conduit à son durcissement de manière considérable et rend, par conséquence, son utilisation conditionnée par l’utilisation de protection externe moyennant des revêtements faisant office de barrière de diffusion à l’oxygène présent dans le sodium liquide à hauteur de quelques ppm. Au cours de ce travail, des revêtements diffusionnels à base siliciures binaires et ternaires sont élaborés essentiellement par cémentation activée en caisse. Leur capacité à protéger le substrat dans des milieux simulant les conditions d’un RNR-Na, caractérisés par un faible potentiel oxydant de O2, est avérée suite à des tests d’oxydation sous hélium impur à 650°C et de corrosion dans le sodium liquide à 550°C (test CorroNa au CEA de Saclay). D’autres tests d’oxydation sous air (cycliques, isothermes et fluage-flexion 3 points) ont montré la bonne résistance des revêtements à des températures au-delà de 900°C grâce à la formation d’une couche protectrice de SiO2, adhérente et compacte. Un autre volet de ce travail a permis d’aborder la stabilité microstructural du système gaine/revêtement dans les conditions accidentelles. Ceci a nécessité le calcul des coefficients d’interdiffusion en s’appuyant parallèlement sur les modèles de croissance multicouche de Wagner et de consommation mutuelle de Buscaglia. En dernier lieu, la coupe isotherme à 1200°C et la projection liquidus du système V-Cr-Si sont étudiés. Cette étape, préliminaire à l’étude du système quaternaire V-Cr-Ti-Si, doit permettre en perspective l’optimisation de l’architecture du revêtement et aider à la compréhension des mécanismes d’oxydation
The use of vanadium alloy V-4Cr-4Ti as fuel cladding in the generation IV sodium cooled fast reactor (SFR) is considered with a great interest thanks to its attractive physico-chimicals properties namely: a good compatibility with liquid sodium, a high neutronic transparency,a good mechanical properties even under irradiation. However, the dissolution of oxygen in vanadium leads to its hardening. This behavior imposes, consequently, the use of on external protection as coatings that can be considered as a barrier against oxygen diffusion contained in liquid sodium at very low concentrations (a few ppm). In this work, binary and ternary diffusional silicides coatings are produced mainly by halide activated pack cementation. Their ability to protect the substrate in media simulating a SFR’s conditions, with a low oxidation potential of O2, is proved according to the results of oxidation tests in impure helium at 650 ° C and corrosion in sodium liquid at 550 ° C (CorroNa test at CEA de Saclay). Other air oxidation tests (cyclic, isothermal and creep-bending 3 points) showed good resistance of coatings at temperatures above 900°C due to the formation of a protective layer of SiO2, adherent and compact. In another part of this work, the microstructural stability of the cladding/coating system in accidental conditions is studied. This required the calculation of interdiffusion coefficients using models of multilayer growth as proposed by Wagner and mutual consumption as proposed by Buscaglia. Finally, the isothermal section at 1200 ° C and the liquidus projection of V-Cr-Si system are studied. This step, preliminary to the study of quaternary V-Cr-Ti-Si system, should allow as a perspective the optimization of the architecture of the coating and help to understand the oxidation mechanisms

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Bigot, Laurent. "Structure homogène et inhomogène de la transition 4I 13/2 ↔ 4I 15/2 de l'amplificateur à fibre dopée erbium dans des verres d'oxydes, de fluorures et de sulfures." Lyon 1, 2002. http://www.theses.fr/2002LYO10035.

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La fin des années 90 a été marquée par le développement des transmissions par fibres optiques. Pour les transmissions longues distances, l'amplificateur à fibre dopée erbium (EDFA) s'est imposé pour régénérer les signaux à 1. 55 æm. Bien que son utilisation se soit généralisée, un grand nombre d'aspects restent à approfondir, comme, par exemple, le lien existant entre la forme de la bande de gain de l'erbium et la structure du verre. Nous avons donc analysé cet aspect du problème en utilisant la spectroscopie de haute résolution. Ainsi, des études par spectroscopie de sélection de sites, affinement de raie résonante (RFLN) et spectroscopie de saturation (SHB) ont été menées sur cinq matrices vitreuses très différentes. Les expériences de RFLN nous ont permis d'analyser la position des niveaux d'énergie ou encore l'élargissement des transitions optiques en fonction de la composition du matériau. Nous avons mis en évidence de grosses différences de distribution de sites ou de champ cristallin entre les matériaux. L'étude de la largeur homogène nous a permis d'isoler les mécanismes responsables de l'élargissement des transitions optiques dans nos verres. Les résultats obtenus ont été reliés au fonctionnement de l'amplificateur et à des problèmes encore mal compris tels que la saturation locale du gain en régime d'amplification. Une étude plus fondamentale basée sur la spectroscopie de saturation a également été menée. Nous avons ainsi pu mettre en évidence l'existence du phénomène de hole burning spectral pour l'ion erbium dans le cas d'un verre de fluorures. La dépendance en température de la largeur homogène aux très basses températures a été analysée et reliée à la théorie des systèmes à deux niveaux (TLS). Une étude de la dynamique de formation du trou caractéristique du hole burning nous a permis de proposer une hypothèse quant au mécanisme à l'origine de la saturation

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Aguiar, Bruno Moreira de. "Desenvolvimento dos Processos de Cominuição, Passivação e Investigação da Cinética de Hidretação Massiva da Liga U-4Zr-2Nb Pelo Processo de Hidretação-Desidretação." CNEN - Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, 2008. http://www.bdtd.cdtn.br//tde_busca/arquivo.php?codArquivo=138.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Neste trabalho foram realizadas a cominuição e passivação da liga metálica U-4Zr-2Nb pelo processo de hidretação-desidretação, bem como o estudo da sua cinética. A obtenção deste material pulverizado através das técnicas da metalurgia do pó é uma etapa necessária e chave na fabricação da pastilha, que será empregada na laminação da placa combustível. Foi escolhida a liga com composição U-4Zr-2Nb devido à sua elevada densidade e baixo teor de elementos de liga, além de suas pequenas seções de choque para nêutrons térmicos. Previamente, foi projetado e construído o equipamento tipo Sievert volumétrico para a cominuição da liga metálica de urânio pelo processo de hidretação-desidretação, operacionalizando-o no modo automático, através da aquisição de dados por intermédio de softwares também desenvolvidos neste trabalho. Juntamente com o desenvolvimento deste equipamento, outro software foi desenvolvido para calcular a cinética de hidretração e a porcentagem hidretada. A seguir, com a utilização deste equipamento, amostras da liga U-4Zr-2Nb foram tratadas termicamente, hidretadas, passivadas, moídas e desidretadas. O processo de cominuição desenvolvido foi realizado nas condições de temperaturas de hidretação variando entre 108C e 295C e a pressão variando entre 2,0 bar e 1,5 bar. Todas as amostras foram hidretadas por completo, independentemente da temperatura de processamento. O tempo de hidretação variou entre 550 a 16176 segundos, de acordo com a temperatura utilizada, sendo mais rápido para temperaturas mais altas. Independentemente dos tratamentos térmicos feitos previamente nas amostras, todas apresentaram somente a fase α e, conseqüentemente, todas as hidretações realizadas foram massivas. Foi desenvolvido também um processo de passivação dos pós obtidos, tendo-se conseguido amostras cominuídas estáveis, ou seja, não apresentaram reações pirofóricas quando expostas ao ar, nem uma excessiva oxidação das mesmas. Para isto, foi utilizada uma mistura de gases contendo 90% de argônio e 10% de oxigênio. Após a passivação, os hidretos foram moídos e passivados novamente para obtenção final do pó metálico. A granulometria final dos pós metálicos obtidos não depende dos tratamentos térmicos da amostra nem da temperatura de hidretação. As partículas maiores se revelaram um aglomerado de partículas menores e, portanto, foi utilizado um processo de moagem para desaglomeração parcial destas partículas, tendo-se obtidos partículas com tamanhos na faixa entre 11,2 e 22,4 μm.
In this work the comminution and passivation of U-4Zr-2Nb alloys by hydrading-dehydrading process was carried out and the kinetics of hydride formation was studied. The obtaining of the powdered material through the techniques of powder metallurgy is a key and necessary step in the manufacture of the pellet useful for providing the fabrication of the fuel plate. An alloy with composition U-4Zr-2Nb was chosen due to their high density and low alloying elements, in addition to its low thermal neutrons cross section. A volumetric Sievert equipment for comminuition of uranium alloys by the process of hydriding-dehydriding was designed and constructed. This equipment operates in an automatic mode through the data acquisition software also developed in this work. Along with the development of this equipment, other software was developed to calculate the kinetic of hydriding and the hydriding amount. Then, using this equipment, samples of the U-4Zr-2Nb alloy were heat treated, hydrided, passivated, milled and dehydrided. The developed comminution process was obtained in the temperature range of 108oC to 295oC and in the pressure range of 1.5 Bar to 2 Bar. All samples were completely hydrided, regardless of the hydriding temperature. The hydriding time ranged from 540 to 16176 seconds, according to the temperature used, being faster at higher temperature. Regardless of the previously heat treatments, all samples showed only the α phase and, consequently, all hydridings were massive performed. It was also developed a passivation process of the obtained powder, and the powdered samples were stable, not pyrophoric and no kind of reaction was observed when exposed to air, without an excessive oxidation. In this case, it was used a gas mixture of 90% argon and 10% oxygen. After passivation, the hydride were milled and passivated again to obtain the metallic powder. The final size of the powdered metal did not depend on the heat treatment of the sample or on the hydriding temperature. The larger particles revealed to be an agglomerate of particles and therefore the milling process partially dismantle these agglomerates into primary particles. The particles size ranged from 11.2 up to 22.4 μm.

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Thomasson, Lübeck Therese. "Jämställdhet, demokrati och metoder för jämställdhet i arbetslivet." Thesis, Växjö University, School of Management and Economics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-224.

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Ly, Sandra, and Helena Sundin. "Tillväxt av solceller i fastighetsbranschen : Investeringar i småskaliga solcellsanläggningar ur ett nätverksperspektiv." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-226903.

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Användningen av solceller har haft global exponentiell tillväxt sedan 2000-talet och många experter menar att solceller har stor potential att utvecklas. På den svenska elmarknaden bidrar solceller dock med en försumbar andel på endast 0,01 %. En av fördelarna med solceller är att de kan nyttja ytor effektivt genom att appliceras på eller integreras i byggnader, vilket har skapat ett intresse hos fastighetsägare. Denna studie avser att studera samspelet mellan aktörerna i processen bakom solcellsinvesteringar samt hur interaktionen skapar värde för involverade aktörer. Detta studeras för att utreda vilka faktorer som kan påverka tillväxten av solceller på den svenska elmarknaden. För att undersöka detta har två fallstudier utförts för fastighetsbolagen Uppsalahem och Specialfastigheter som båda har befintliga solcellsanläggningar. Studiens teoretiska ramverk utgår ifrån en övergripande nätverksteori samt en resursanalys med hjälp av 4R-modellen där interaktionerna mellan aktörernas resurser analyseras. Genom att studera interaktionerna kan värden identifieras. Vår studie visar att på grund av höga initialkostnader och låg ersättning för producerad el kan solcellsinvesteringar vara ekonomiskt olönsamma beroende på solcellsteknik och installationsteknik. Dessutom har verkningsgraden potential att utvecklas och priset för solcellsgenererad el är högt i förhållande till det låga elpriset. Ytterligare en utmaning är att bibehålla balansen vid ökad anslutning av solceller, vilket kan kräva stora satsningar och investering i elnätet. Dessa skapar utmaningar för solcellernas tillväxt på elmarknaden. Dock visar resultaten att solcellsinvesteringar bidrar till både sociala och miljömässiga aspekter, såsom långsiktig hållbarhet, stärkt varumärket och kunskapsutbyte. Dessutom bidrar det till att företaget skapar affärsrelationer med andra aktörer samt ligger i framkant vad gäller tekniken, och detta är i sig viktigt i omställning mot ett hållbart samhälle. Investeringar i solcellsanläggningar har därmed inte alltid en direkt ekonomisk lönsamhet men indirekta effekter skapar värde som gör att det finns incitament att investera.

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Apricò, Karina 1977. "[3H](2S,4R)-4-methylglutamate as a novel radioligand for brain glutamate transporters." Monash University, Dept. of Pharmacology, 2003. http://arrow.monash.edu.au/hdl/1959.1/5497.

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Stenhols, Marcus. "Dolls 4R: Ett mått på kunskapsutveckling? : En studie om bedömning av studentens kunskapsutveckling." Thesis, Södertörns högskola, Lärarutbildningen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-23468.

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Aim: The aim of this study was to examine a way to measure students’ knowledge development by using a self-made measure instrument based on William Doll’s postmodern curriculum. Question: Is it suitable to use an self-made measure instrument based on William Doll’s post-modern curriculum theory to measure development of knowledge? Methods: The study was based on process-hermeneutics and was focused on analysingcollege students’ written and oral reflective thoughts. The data was collected over three lessons, where six students’ written reflective thoughts were handed in. An observation was carried out each lesson for an extra control of validity. A group of nine students was taken as a control of the measure instrument’s reliability. The measure instrument was built from Doll’s categories: Richness, Recursion, Relations and Rigor. Each category was divided by three levels of thinking. Each reflective task was judged by two judges. An extra text analysing was done to control whether there was a knowledge development outside the measure instrument. Results: The results of the judged reflective tasks was tested with both Cohen’s Kappa and Cronbach’s alpha. Cohen’s Kappa revealed the accordance of k= -0.047 n=9 for the control group and k= 0.364 n=14 (reflective tasks) for the test group. Cronbach’s alpha revealed a consistency of 0.645 n=9 (students) in the control group and 0.351 n=6 in the test group. After three lessons, judge one considered 66%, judge two 33% of the students demonstrated acquired development of knowledge. One criteria, Rigor, showed a low rate of acquired knowledge development. The reason behind that could be in the nature of the theory behind Rigor itself, and the students’ understandings of it. Conclusion: The results does not support the premises of this study. The tests of reliability fail to support the claim that the measure instrument should be reliable enoughto be used to measure knowledge. The instrument needs to be altered to be able toserve as a reliable tool for measurement. Further research is needed in order to reveal if the instrument and Doll’s 4R theory are useful as curriculum and measuring tool for knowledge development.

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Skog, Emma. "Betydelsen av interleukin 4 receptorn (IL-4R) i stimulering av lymfom- och leukemiceller." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-24758.

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Cytokiner eller interleukiner är signalpeptider med låg molekylär vikt somreglerar många viktiga funktioner. De kan delas in i två grupper beroende på deraseffekt på celler. Interleukin 4 (IL-4) till exempel kan tillhöra gruppentillväxtfaktorer medan interleukin 6 (IL-6) kan tillhöra gruppen aktiverings- ellerdifferentieringsfaktorer. IgM-receptorn eller B-cellsreceptorn, BCR, finns på Bcelleroch är membranbundna immunoglobuliner (mIg) som har tvåhuvuduppgifter; att förmedla signaler som styr B-cellens utveckling samt att bindain antigen som sedan ska presenteras för T-celler. I studien aktiverades B-cellermed antikropp mot IgM (anti-IgM) samt rekombinant IL-4. Efter stimuleringanalyserades IL-6 produktionen med enzyme-linked immunosorbent assay(ELISA). Syftet med studien var att karakterisera uttrycket av IL-4 receptorn pålymfom- och leukemiceller med flödescytometri och polymeras chain reaction(PCR) samt produktion av IL-6 med ELISA. ELISA-analysen visade att tvåcellinjer, stimulerade Sp53 och stimulerade samt kontroller av WaC3CD5+, gaven ökning av IL-6 produktionen. Vid jämförelse med ELISA-resultaten ochflödescytometri-analyserna ser man att WaC3CD5+ som producerat storamängder IL-6, har en liten andel IL-4 receptorer på cellytan. Resultatet av PCRanalysenvisar att det var framförallt Sp53 som fick höga mängder IL-4R mRNA,men även I83, U2932 och WaC3CD5+ fick positiva resultat. Resultaten i dennastudie är preliminära och för att få mer säkerställda resultat krävs att alla analysergörs om ett antal gånger för att få ett mer tillförlitligt resultat.
Cytokines or interleukins are signal peptides of low molecular weight, whichregulates many important functions. They can roughly be divided into two groupsor divisions due to their effect on cells. Interleukin 4 (IL-4), for example, belongsto the group growth factors while interleukin-6 (IL-6) belongs to the groupactivation or differentiation factors. IgM receptors or B cell receptors, BCR, areexpressed on B cells and are membrane-bound immunoglobulins (mIg) and havetwo main functions: to convey signals that control B cell activation and to bindantigen which will then be presented to T cells. In the study B cells were activatedwith antibodies against IgM (anti-IgM) and recombinant IL-4. After stimulationthe IL-6 production was analysed by enzyme-linked immunosorbent assay(ELISA). The purpose of this study was to characterize the expression of IL-4receptor in lymphoma and leukemia cells by flow cytometry and polymerasechain reaction (PCR) and furthermore the production of IL-6 by ELISA. ELISAanalysis showed that two cell lines, stimulated Sp53 and stimulated and control ofWaC3CD5+, resulted in an increased IL-6 production. When comparing ELISAresults and flow cytometry assays, it can be seen that WaC3CD5+, whichproduced large amounts of IL-6, has a small percentage of IL-4 receptors on thecell surface. The results of the PCR analysis shows that particularly Sp53displayed high amounts of IL-4 mRNA, but also I83, U2932 and WaC3CD5+were positive for IL-4 mRNA. The results of this study are preliminary, and to getmore trustworthy results, all analyses have to be repeated to get more reliableresults.

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Souza, Vanessa Moura de. "Avaliação do atrito e do comportamento do desgaste de um aço ABNT H13 revestido com Cr3C2-25(NiCr) e WC-10Co-4Cr através do processo de aspersão térmica oxicombustível de alta velocidade (HVOF)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/169306.

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O desgaste é um dos fatores que causam a maior parte das falhas e redução na vida útil de ferramentas, além de resultar em produtos com condições superficiais inadequadas. A crescente demanda da indústria por menores custos, maior produtividade e melhor qualidade estão entre as justificativas para que se busquem maneiras de incrementar o desempenho dessas ferramentas. Neste contexto, o trabalho tem como objetivo avaliar e caracterizar superfícies projetadas para resistência ao desgaste utilizando o processo de aspersão térmica oxicombustível de alta velocidade (HVOF). Fez-se um estudo comparativo de caracterização e comportamento tribológico de um aço ferramenta com deposição por aspersão térmica de dois diferentes revestimentos. O estudo abrange o aço ABNT H13, utilizando o tratamento superficial de aspersão térmica HVOF com revestimentos de Cr3C2-25(NiCr) e WC-10Co-4Cr. A avaliação da superfície e do comportamento tribológico envolveu perfis de microdureza, análise de fases por difração de raios X, metalografias, obtenção da composição química, caracterização da rugosidade, ensaio de abrasão e adesão, pino-disco e ensaio do anel. O objetivo de conseguir aumentar a resistência ao desgaste utilizando um aço ferramenta com deposição via processo de HVOF, bem como o de caracterizar este processo foi alcançado. A utilização do aço ABNT H13 com deposição via aspersão térmica HVOF e revestimentos à base de carboneto de cromo e tungstênio demonstrou-se recomendável para proteção de substratos, fornecendo alta dureza e boa resistência ao desgaste. O revestimento de WC-10Co-4Cr obteve o melhor desempenho geral, apresentando uma microdureza 192% maior frente ao aço sem revestimento, uma redução de 315% do coeficiente de atrito, além de uma adesão maior ao substrato quando comparado com o revestimento Cr3C2-25(NiCr).
Wear is one of the factors that cause most of the failures and reduction of lifespan for tools, it also results in products with no quality in the surface conditions. The increasing demand of the industry for lower costs, higher productivity and better quality are among the justifications for finding ways to increase the performance of these tools. In this context, the objective of this work is to evaluate and characterize surfaces designed for wear resistance using the high velocity oxyfuel (HVOF) thermal spray process. A comparative study of characterization and tribological behavior of a tool steel with thermal spray deposition was performed for two different coatings. The study covers the ABNT H13 steel, using the surface treatment of HVOF thermal spray with coatings of Cr3C2-25(NiCr) and WC-10Co-4Cr. The surface and the tribological behavior evaluation involved microhardness profiles, phase analysis by x-ray diffraction, metallography, chemical composition, roughness characterization, abrasion and adhesion test, pin-on-disk and ring test. The objective of increasing the wear resistance using a tool steel with deposition through HVOF process, as well as to characterize this process was achieved. The use of ABNT H13 steel with chrome and tungsten carbide coatings deposited by thermal spray HVOF has proved to be recommended for substrates protection, providing high hardness and good wear resistance. The WC-10Co-4Crcoating had the best overall performance, presenting a microhardness 192% higher than the steel with no coating, a reduction of 315% of the coefficient of friction, and a higher adhesion to the substrate compared to the Cr3C2-25(NiCr) coating.

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Weiß, Norman. "Dieter Blumenwitz/Gilbert H. Gomig/Dietrich Murswick (Hrsg.): Minderheitenschutz und Demokratie (Staats- und völkerrechtliche Abhandlungen 4er Studiengruppe für Politikund Völkerrecht ; Bd. 20) / [rezensiert von] Norman Weiß." Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2011/5607/.

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rezensiertes Werk: Blumenwitz, Dieter ; Gomig, Gilbert H. ; Murswick, Dietrich (Hrsg.): Minderheitenschutz und Demokratie (Staats- und völkerrechtliche Abhandlungen 4er Studiengruppe für Politikund Völkerrecht ; Bd. 20.) - 2004, 204 S. ISBN 3-428-11572-4

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Hlaka, Lerato. "Investigation of minor groove binders (MGB), non-ionic surfactant vesicles (NIV) delivery systems and IL-4i1 as novel pathogen- and host-directed drug therapy for tuberculosis." Doctoral thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/31054.

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Tuberculosis (TB), caused by Mycobacterium tuberculosis is the leading infectious disease epidemic that claims over 1.6 million lives, while 10 million fell ill in 2017. South Africa is burdened with the third highest global incidences following India and China with high rates of co-infections with HIV and highest numbers of multi-drug resistant (MDR) and extremely resistant (XDR) TB per capita. The current treatment regimen is decades old and requires a prolonged period of 6 months. The lack of efficient TB therapy and the emergence of MDR and XDR TB, there is an urgent need to find new drug targets for TB therapy through understanding the complex host-pathogen interactions. This may then lead to pathogen, host-directed therapies (HDT) or adjunct therapies as well as the development of effective drugs and drug formulations for the treatment of TB. Here we aimed to investigate potential targets for pathogen-and host-directed therapies for TB. We screened the anti-mycobacterial activity of 172 minor groove binder (MGB) compounds that selectively bind to AT-rich regions of the minor groove of bacterial DNA with the helical structure matching that of DNA in Mtb culture. Of the 172 total compounds screened 17 hits were identified, of which 2, MGB 362 and MGB 364 displayed intracellular mycobactericidal activity against Mtb HN878 at an MIC50 of 4.09 and 4.19 μM, respectively, whilst being non-toxic. Encapsulation of MGBs into non- ionic surfactant vesicles (NIVs) demonstrated a 1.6- and 2.1-fold increased intracellular mycobacterial activity, similar to that of rifampicin when compared with MGB alone. Treatment with MGB 364 or MGB 364 formulation did not cause DNA damage in murine infected macrophages as displayed by low expression of γ-H2Ax compared to H2O2 and DMSO. Intranasal administration of MGB 364 and MGB-NIV 364 formulation showed one log reduction in bacterial burden with improved pathology and immune cytokine production when in formulation. However, intranasal administration of 10 mg/kg MGB 362 together with rifampicin had no effect on bacterial loads. In summary, the data demonstrate the potential of MGB as a novel class of drug/chemical entity in anti-TB therapy and NIVs as an effective delivery system in a novel anti-TB formulation. Using deep CAGE and small RNA (CHIP-seq) technologies, International Center for Genetic Engineering and Biotechnology’s Cytokines and Diseases lab in collaboration with the RIKEN Center for Integrative Medical Sciences (Yokohama, Japan) performed a novel transcriptomics study approach by conducting a genome-wide transcriptional analyses of RNA transcripts from classically activated macrophages (caMph) and alternatively activated macrophages (aaMph) during Mtb infection. We identified host target genes that may play a role in host immune subverting mechanism by Mtb to hide away from host effector functions providing a possible target for host-directed therapy for tuberculosis. It is postulated that Mtb modulates the transcriptional landscape of IL-4/IL13 alternatively activated macrophages (aaMph) to escape killing by reactive nitrogen intermediates (NO) and reactive oxygen species (ROS) functions by IFN-γ stimulated classically activated macrophages (caMph). Here we report on the immunoregulatory role of IL-4i1, a candidate gene that was upregulated in aaMph during Mtb infection. IL-4i1 is a secreted L-amino oxidase with antibacterial properties. The enzyme converts Phenylalanine (Phe) into phenylpyruvate releasing toxic products ammonia and hydrogen peroxide (H2O2) which in-turn cause immunosuppression of effector T-cells by directly inhibiting polarization, proliferation and function or by promoting the generation of Foxp3 T-regulatory cells. Thus suggesting that IL-4i1 is involved in immune-regulatory mechanisms and may be implicated in immune evasion mechanisms by the pathogen. Here we report on the role of IL-4i1 on tissue localized T-cell activation and proliferative status thus maintaining immune local immune homeostasis. Thus showing that the absence of IL-4i1 could cause autoimmunity. To determine the functional role of IL-4i1 during Mtb infection, IL-4i1 deficient mice and wild-type littermate controls were infected with H37Rv and hypervirulent HN878 Mtb strain. IL-4i1 deficient mice were highly resistant to both strains of Mtb at 12- and 21-days post-infection as denoted by significant reduction in bacterial loads, reduced inflammation, reduced tissue iNOS expression reduced recruitment of interstitial macrophages, pro-inflammatory cytokines showed a trend for reduction. Interestingly there was a significant increase in NO production in infected tissues. There was an increase in M1-like macrophages that correlated with increased pro-inflammatory cytokines and chemokines. These data suggested that IL-4i1 regulates macrophage-mediated inflammatory responses during acute Mtb infection thus showing potential as an immunomodulatory target for TB HDT therapy. The study thus provides a framework for new drug targets for the development of new effective drugs and vaccines for TB therapy.

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Ramallo, Ribera Ruben. "Forças motrizes da transferência de vermelho 40 e vermelho ponceau 4R em sistemas aquosos bifásicos." Universidade Federal de Viçosa, 2017. http://www.locus.ufv.br/handle/123456789/14028.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Os sistemas aquosos bifásicos (SABs) são uma ferramenta útil quando se pensam na extração, purificação e concentração de espécies químicas. No entanto, a termodinâmica de partição de solutos nesses sistemas ainda é pouco compreendida e desperta o interesse de vários pesquisadores. Há poucos estudos que trazem um enfoque termodinâmico que contribua para compreensão das forças motrizes que regem o processo de transferência de solutos em SABs. Para um melhor entendimento do processo de partição e para saber quais são as forças motrizes que determinam este processo utilizou-se dois corantes com estruturas químicas parecidas como sondas moleculares para que através delas compreender o processo de partição. Neste trabalho a termodinâmica de partição dos corantes azoicos Vermelho 40 (V-40) e Vermelho Ponceau 4R (VP-4R) nos SABs formados por poli (óxido de etileno) + sal + água foi estudada. Para uma melhor compreensão do processo de partição distintos efeitos como a dependência de K com a concentração do corante, a massa molar, o efeito do ânion, cátion e hidrofobicidade do polímero foram estudados. Em todos os SABs estudados neste trabalho os valores de K foram maiores que a unidade alcançando valores máximos de 2400 e 9000 para V-40 e VP-4R respectivamente em sistemas formados por sais orgânicos e valores máximos de 55000 e 22500 para V-40 e VP-4R respectivamente em sistemas formados por sais inorgânicos. Á mudança do ânion do sal formador do SAB mostra que o processo de partição é pouco influenciado pelo aníon. O estudo do efeito da hidrofobicidade do polímero mostra que as interações hidrofóbicas não dominam o processo de partição dos corantes V-40 e VP-4R. Avaliaram-se os parâmetros termodinâmicos de transferência como a variação da energia livre de Gibbs (∆trGΘ) , a variação da entalpia de transferência (∆trHΘ) e da entalpia de transfência (∆trSΘ), os valores de ∆trGΘ mostram um diminuição lineal para ambos corante -12,73 kJ/mol < ∆tr GV-40 < -24,93 kJ/mol e -11,776 kJ/mol < ∆trGVP-4R< -22,830 kJ/mol, os valores negativos de HΘ) mostram que a entalpia é a força motriz que contribui ao processo de partição dos corantes, com valores de -194,55 kJ/mol < kJ/mol, -70,78 kJ/mol <∆trHV-40 < -80,36 kJ/mol< -188,00 kJ/mol. Estes dados mostram a existência da interação corantes-polímero. Esta afirmação é confirmada com o resultado da massa molar do polímero, onde o valor K aumenta com a massa molar do polímero para ambos dos corantes, reforçando a ideia que o corante interage mais favoravelmente com o polímero do que com o sal.
Aqueous biphasic systems (ATPSs) are a useful tool when thinking about the extraction, purification and concentration of chemical species. However, the solute partitioning thermodynamics in these systems are still poorly understood and arouse the interest of several researchers. There are few studies that bring a thermodynamic approach that contributes to the understanding of the driving forces that govern the process of transfer of solutes in ATPSs. For a better understanding of the partitioning process and to know the driving forces that determine this process we used two dyes with similar chemical structures as molecular probes. In this experiment the thermodynamics of partitioning of dyes Allura red (AR) and Red Ponceau 4R (RP-4R) in ATPSs formed by poly (ethylene oxide) + salt + water was studied. For a better understanding of the partitioning process distinct effects such as the dependence of K on the dye concentration, molar mass, anion effect, cation and hydrophobicity of the polymer were studied. In all ATPS studied in this work K values were higher than the unit, reaching maximum values of 2400 and 9000 for AR and RP-4R respectively in systems formed by organic salts and maximum values of 55000 and 22500 for AR and RP-4R respectively in systems formed by inorganic salts. The change in the anion of the salt forming ATPS shows that the partitioning process is little influenced by the anion. The study of the hydrophobicity effect of the polymer shows that hydrophobic interactions do not dominate the partitioning process of AR and RP-4R dyes. The thermodynamic transfer parameters such as the Gibbs free energy variation (∆trGΘ) , the transfer enthalpy change (∆trHΘ) and the transfer entropy (∆trSΘ) , The values (∆trGΘ) of show a linear decrease for both dyes, with values of -12,73 kJ/mol < kJ/mol < ∆tr GV-40 < -24,93 kJ/mol and -11,776 kJ/mol < ∆trGVP-4R∆trGVP-4R <- 22,830 kJ/mol, The negative values of (∆trHΘ) show that the enthalpy is the driving force that contributes to the dye partitioning process, with values of -194,55 kJ/mol < ∆trHV-40 < -80,36 kJ/mol, -70,78 kJ/mol < ∆trGVP-4R< -188,00 kJ/mol. These data show the existence of the dye-polymer interaction. This assertion is confirmed by the result of the molar mass of the polymer, where the K value increases with the molar mass of the polymer in both of the dyes, reinforcing the idea that the dye interacts more favorably with the polymer than with the salt.

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Persson, Carina. "Lärande om idrottsevenemang vid ideellt arbete : - om överföring och utveckling av kunskaper mellan föräldrar i ett föreningssammanhang." Thesis, Linköpings universitet, Institutionen för beteendevetenskap och lärande, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-88414.

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Idrotten engagerar och berör människor. Lägg därtill att ideellt arbete sysselsätter många föräldrar. Detta är bakgrunden till uppsatsen. Uppsatsen handlar om föräldrars lärande. Studiens syfte är att beskriva och analysera överföring och utveckling av kunskaper och erfarenheter mellan föräldrar i ett föreningssammanhang om att planera och genomföra idrottsevenemang. Studien baseras på intervjuer med föräldrar och personal inom en förening i lagidrottens värld. Det empiriska materialet analyseras främst utifrån 4I-processen, en modell av Crossan, Lane och White (1999). Resultatet visar på inslag av insikts-, interpretation- och integreringsprocesser, samt avsaknad av institutionaliseringsprocessen. Föräldrar kan lära, de lär sig från andra föräldrar och genom eget arbete. Men föräldrarna får inte stöd av organisationen i lärandet, inte heller tas föräldrars lärande omhand av organisationen. Mönstret är lika över åren. Föräldrarna hanterar merparten av evenemangsarbetet, med flest arbetstimmar innan evenemanget. Tillvaratagande av föräldrars lärande ger förutsättningar för att göra evenemangsarbetet effektivare för alla involverade parter.

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Sunebäck, Emma, and Caroline Lindblom. "Intern resursallokering inom franchiseföretag." Thesis, Högskolan i Gävle, Avdelningen för ekonomi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-15456.

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Titel: Intern resursallokering inom franchiseföretag Nivå: C-uppsats i företagsekonomi Författare: Caroline Lindblom & Emma Sunebäck Handledare: Lars-Johan Åge Biträdande handledare: Jens Eklinder Frick Datum: 2013-08 Syfte: Syftet med vår studie är att analysera hur franchiseföretag kombinerar sina resurser internt. Detta gör vi utifrån det teoretiska ramverket 4R. Vi kommer att genomföra studien ur franchiseföretags synvinkel då vi tror att de samarbetar mer kring resurser än företag från olika koncerner. Det gör att en studie av franchiseföretag och deras sätt att kombinera resurser blir intressant. Genom studien vill vi belysa hur resursallokering inom franchiseorganisationen kan påverka resursvärdet som uppnås. Metod: För att genomföra studien har vi samlat information från artiklar och litteratur samt genomfört intervjuer på två franchiseföretag inom fastighetsmäklarbranschen. Vi har genomfört en komparativ studie genom att intervjua tre franchisetagare samt huvudkontoret på respektive företag. Slutsats: Vår studie visar att franchiseorganisationens storlek påverkar behovet av ett välutvecklat internt affärssystem. Detta för att på bästa sätt kunna nyttja resurser gemensamt och utbyta erfarenheter. Tidigare forskning visar att det ger ett ökat värde att kombinera resurser gemensamt inom organisationen, något som vår studie stödjer. Förslag till fortsatt forskning: Framtida studier kan utföras genom en liknande empirisk undersökning. Dock med en studie av andra franchiseorganisationer än fastighetsmäklarföretag. Vidare forskning kan baseras på slutsatsen att organisationens storlek påverkar behovet av ett internt affärssystem genom att studera denna skillnad djupare. Uppsatsens bidrag: Vi har konstaterat att företagen upplever ett större värde av att kombinera sina resurser gemensamt inom franchiseorganisationen. Möjligheten till detta samarbete minskar om företaget inte är del av ett franchisekoncept. Nyckelord: Franchise, interna nätverk, 4R, resurser, integration, samarbete och resursvärde.
Title: Internal allocation of resources within franchises Level: Bachelor thesis in Business Author: Caroline Lindblom & Emma Sunebäck Supervisor: Lars-Johan Åge Assistant supervisor: Jens Eklinder Frick Examiner: Aihie Osarenkhoe Date: 2013-08 Purpose: The purpose of our study is to analyze how franchises combine their resources internally. We do this based on the theoretical framework 4R. We have conducted the study from the point of view of franchise companies based on the hypothesis that they are collaborating more on resources than companies from different concerns. The study aims to increase the knowledge of how the allocation of resources within the franchise organization can affect the resource value achieved. Method: To conduct the study, we have collected information from articles and literature, and conducted interviews on two franchises in the real estate brokerage industry. We conducted a comparative study by interviewing three franchisees and head office of the respective companies. Conclusion: The size of the franchise organization affect the need of a well developed internal business system. This is due to the best possible use of collective resources and the exchange of experiences. Previous research shows that combining resources within the organization gives a greater value, which our study supports. Suggestions for future research: Future studies can research through a similar empirical study. However, a study of other franchise organizations, other than real estate brokerage firms. Further research can be based on the conclusion that the size of the organization affects the need for an internal business system by studying this difference. Essay submissions: We have found that companies are experiencing a greater value in combining their resources jointly within the franchise organization. The opportunity for this collaboration is reduced if the company is not a part of a franchise concept. Keywords: Franchise, internal networks, 4R, resources, integration, collaboration and resource value.

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Wang, Jie. "The Study of the Effects of (1S,2E,4R,6R,-7E,11E)-2,7,11-cembratriene-4,6-diol on Microglia Polarization Using an Ischemia in Vitro Model." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491559717910191.

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Flodin, Elin, and Johanna Samuelson. "Jobbigt med job-hopping? : En kvalitativ studie om hur hög personalomsättning påverkar förutsättningarna för organisatoriskt lärande." Thesis, Uppsala universitet, Institutionen för pedagogik, didaktik och utbildningsstudier, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-433792.

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Denna studie syftar till att bidra med kunskap om hur hög personalomsättning påverkar förutsättningarna för organisatoriskt lärande genom att undersöka hur det informella lärandet på individ- och gruppnivå påverkas av att medarbetare ofta byts ut. För att uppnå syfte och frågeställningar har vi genomfört kvalitativa intervjuer av semistrukturerad karaktär med sex medarbetare från en statlig myndighet. Empirin har analyserats utifrån Crossan, Lane och Whites (1999) teori om organisatoriskt lärande genom 4I-processen. Resultatet visar på att hög personalomsättning på individnivå bidrar till nya insikter och ny kunskap bland medarbetare genom att nyanställda ifrågasätter befintliga arbetssätt. Det visar sig även att nyanställda kan tillföra praktisk kunskap men att arbetsuppgifterna oftast är för specifika för att de ska ha möjlighet att förse medarbetarna med ny kunskap. Hög personalomsättning orsakar också merarbete för de befintliga medarbetarna, vilket kan begränsa lärandet. På gruppnivå visar det sig vara av vikt att dela med sig av kunskap till nyanställda för att integrera dem i arbetet. Däremot orsakar hög personalomsättning svårigheter vad gäller gruppens utveckling, vilket medför en begränsning av det informella lärandet eftersom förtroendet mellan kollegor försvinner samt att kunskap går förlorad när medarbetare säger upp sig.

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Schwegler, Friederike [Verfasser]. "Synthese und Testung von (4R,5S)/(4S,5R)-2,4,5-Triaryl-4,5-dihydro-1H-Imidazolen / Friederike Schwegler." Berlin : Freie Universität Berlin, 2010. http://d-nb.info/1024105121/34.

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Sefer, Birhan. "Environment related surface phenomena and their influence on properties of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo : oxidation at elevated temperature and corrosion during chemical treatment." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/403884.

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This thesis covers investigation of the surface phenomena of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo alloys related with oxidation at elevated temperature and corrosion during chemical treatment in hydrofluoric-nitric acid (HF/HNO3) solutions. The explored phenomena are related to manufacturing and service conditions of aero-engine components. During manufacturing and operation, the alloys are sunjected to elevated temperatures in oxygen environment. In such conditions an oxide on the surface and an oxygen enriched layer below the oxide, commonly referred as alpha-case is formed. Alpha-case is a hard and brittle layer that is detrimental to the mechanical properties and must therefore be completely eliminated. A conventional method for elimination of alpha-case is chemical processing in HF/HNO3 solutions, i.e. chemical milling. Isothermal oxidation treatments in air at 500, 593 and 700 ºC for up to 500 hours were carried out in this thesis. Both alloys developed rutile type of oxide structure and Ti-6Al-2Sn-4Zr-2Mo exhibited stronger oxidation resistance than Ti-6Al-4V. Transition from parabolic to linear oxidation rate was observed at 700 ºC and = 200 hours for both alloys. The difference in the oxidation kinetics of the two alloys is suggested to be related with the chemical composition of the alloys. The oxygen enriched layer, i.e. alpha-case layer, was characterised and its thickness was measured using conventional metallographic and microscopic techniques. The parabolic rate constants, the oxygen diffusion parameters and activation energies were estimated in the temperature range of 500-700 ºC for both alloys. Moreover, the oxidation for 500 hours at 700 ºC resulted in microstructural changes and element re-distribution. The bulk and alpha-case layer hardness at micro- and nano-scale were measured using microhardness and nanoindentation techniques. The alpha-case layer had higher hardness due to the solid solution strengthening effect of the diffused oxygen. The effect of chemical milling in 1:11 HF/HNO3 solution on the surface integrity, and the influence on low cycle fatigue (LCF) strength of cast Ti-6Al-2Sn-4Zr-2Mo alloy was investigated. Five and sixty minutes chemical processing times and three imposed total strain ranges in fatigue tests were evaluated. Significant drop in fatigue life was observed for the samples etched before LCF testing, as compared to the non-etched samples. The influence from etching was found to be most detrimental for fatigue samples tested at the lowest strain ranges. The fatigue life reduction was correlated with the number of crack initiation sites. Multiple crack initiation sites were observed for the etched samples, whereas only one crack initiation site was discerned in the non-etched samples. Inspection of the surface of the etched samples revealed selective and severely etched prior ß grain boundaries and pit formation at the triple joints of the prior ß grain boundaries. These surface defects were considered as stress raisers promoting an earlier fatigue crack initiation. The influence of two molar concentration ratios of HF and HNO3 acids (1:3 and 1:11) on the corrosion behaviour of cast Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo were investigated by electrochemical and atomic force microscopy (AFM) techniques. The corrosion of the two alloys was a function of the concentration ratio of the acids and also of the alloys¿ chemical compositions. The AFM measurements showed faster dissolution rate of the a-phase than the ß-phase in the Widmanstätten microstructure. It was considered that the reason for this is formation of local micro-galvanic cells between the phases. Moreover, the Volta-potential was measured using scanning Kelvin probe force microscopy (SKPFM) and the obtained maps revealed difference in the Volta-potential between the a- and the ß-laths in both alloys. This observation strengthened the likelihood for formation and operation of micro-galvanic cells between the phases.
En esta tesis doctoral se estudian los fenómenos superficiales relacionados con la oxidación a alta temperatura y la corrosión producidos durante el tratamiento químico en soluciones de ácido fluorhídrico-nítrico (HF-HNO3) en las aleaciones Ti-6Al-4V y Ti-6Al-2Sn-4Zr-2Mo. Estos fenómenos se producen durante la fabricación y el servicio de componentes para motores aeronáuticos, pues se dan condiciones de elevada temperatura en un ambiente rico en oxígeno, las cuales favorecen la formación de óxido en la superficie y también de una capa enriquecida en oxígeno debajo del óxido, comúnmente conocida como alpha-case o capa alfa. La alpha-case es una capa dura y frágil, perjudicial para las propiedades mecánicas, por lo que debe ser minimizada o totalmente eliminada. Un método convencional para eliminar la capa alfa es el procesado químico en soluciones de ácido fluorhídrico-nítrico, conocido como chemical milling. En este estudio se han efectuado tratamientos isotérmicos en aire a 500, 593 y 700 °C, con duración máxima de 500 horas. Ambas aleaciones desarrollaron óxido tipo rutilo, en tanto que la Ti-6Al-2Sn-4Zr-2Mo mostró mejor resistencia a la oxidación que la Ti-6Al-4V. Se observó una transición de la velocidad de oxidación de parabólica a lineal a 700 °C y tiempos = 200 horas, para ambas aleaciones. Las diferencias en la cinética de oxidación entre ambas aleaciones se han relacionado con su composición química. La capa rica en oxígeno, i.e. alpha-case, fue caracterizada y su espesor medido mediante técnicas metalográficas. Se observó que la velocidad de crecimiento de la capa alfa seguía una relación parabólica con el tiempo para ambas aleaciones. La difusión del oxígeno y la energía de activación se estimaron en el rango de temperaturas de 500-700 °C. Adicionalmente, se comprobé que el tratamiento isotérmico a 700 °C durante 500 horas dio lugar a cambios microestructurales y a la redistribución de elementos. Las durezas del interior y de la capa alfa se midieron a escalas micro- y nano- mediante técnicas de microdureza y nanoindentación. La capa alfa mostró mayor dureza debido al efecto de endurecimiento por solución sólida debido al oxígeno difundido. El efecto de la solución 1:11 HF-HNO3 en la integridad superficial y en la resistencia a fatiga en el régimen de oligofatiga (LCF = Low Cycle Fatigue) de la aleación Ti-6Al-2Sn-4Zr-2Mo fue investigado. Se evaluaron tiempos de procesado químico cortos y largos (5 y 60 minutos) y tres valores de amplitud de deformación total. Se observó una significativa disminución de la vida a fatiga para las muestras atacadas antes de los ensayos LCF, en comparación con las muestras no atacadas. La influencia del ataque se mostró más perjudicial a bajos valores de deformación impuesta. La reducción en la vida a fatiga se correlacionó con el número de zonas de iniciación de grietas. Múltiples zonas se observaron para las muestras atacadas, mientras que solo un lugar de nucleación de grieta se detectó para las no atacadas. La inspección de las superficies de las muestras atacadas reveló un ataque selectivo y severo en los bordes de grano prior beta y la formación de picaduras en los puntos triples de los bordes de grano prior beta. Estos defectos superficiales fueron considerados como exaltadores de tensiones que promueven la temprana nucleación de las grietas de fatiga. Se investigó la influencia en el comportamiento a corrosión de Ti-6Al-4V y Ti-6Al-2Sn-4Zr-2Mo de dos diferentes relaciones de concentración (1:3 y 1:11) de los ácidos HF y HNO3. Se emplearon para ello técnicas electroquímicas y microscopía de fuerza atómica (AFM). La corrosión de las dos aleaciones depende de la concentración de HF-HNO3 y posiblemente también de sus composiciones químicas. Las medidas de AFM revelaron una velocidad de disolución mayor de la fase alfa que de la beta en la microestructura tipo Widmanstätten. Se considera que la razón de esta disolución selectiva es la formación de celdas micro-galvánicas.

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Panayotov, Dobromir, Sören Kliem, Siegfried Mittag, Ulrich Rohde, Bonka Ilieva, Andre Seidel, and Ulrich Grundmann. "Adaption, Validierung und Anwendung fortgeschrittener Störfallanalysecodes mit 3D Neutronenkinetik - WTZ mit Bulgarien." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29641.

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Im Rahmen eines vom BMBF/BMWi geförderten WTZ-Vorhabens wurde dem Institute for Nuclear Research and Nuclear Energy (INRNE) in Sofia der Programmcode DYN3D sowie der gekoppelte Programmkomplex ATHLET-DYN3D verfügbar gemacht. Dabei stellt dieser Programmkomplex eine Anbindung des im FZR entwickelten 3D Kernmodells DYN3D an den thermohydraulischen Systemcode ATHLET der GRS dar. Zur Validierung dieser Programmcodes wurde eine Messdatensammlung zu einem Inbetriebnahmeexperiment am Block 6 des KKW Kozloduj (WWER-1000/320) erstellt. Die Ergebnisse der durchgeführten Validierungsrechnungen wurden mit den Messwerten aus der Datensammlung verglichen. In den Programmcode DYN3D wurde von den bulgarischen Experten ein vereinfachtes Modell zur Simulation von Querströmungen zwischen den Brennelementen integriert. Dieses Querströmungsmodell ermöglicht es, Prozesse mit asymmetrischen Randbedingungen realistischer zu betrachten. Eine erste Bewertung des implementierten Strömungsmodells erfolgt durch Vergleichsrechnungen zwischen dem modifizierten DYN3D Code und dem Unterkanalanalyse-Code COBRA-4I sowie auf der Grundlage von verfügbaren Messdaten aus dem KKW Kozloduj.

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Panayotov, Dobromir, Sören Kliem, Siegfried Mittag, Ulrich Rohde, Bonka Ilieva, Andre Seidel, and Ulrich Grundmann. "Adaption, Validierung und Anwendung fortgeschrittener Störfallanalysecodes mit 3D Neutronenkinetik - WTZ mit Bulgarien." Forschungszentrum Rossendorf, 2001. https://hzdr.qucosa.de/id/qucosa%3A21791.

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Im Rahmen eines vom BMBF/BMWi geförderten WTZ-Vorhabens wurde dem Institute for Nuclear Research and Nuclear Energy (INRNE) in Sofia der Programmcode DYN3D sowie der gekoppelte Programmkomplex ATHLET-DYN3D verfügbar gemacht. Dabei stellt dieser Programmkomplex eine Anbindung des im FZR entwickelten 3D Kernmodells DYN3D an den thermohydraulischen Systemcode ATHLET der GRS dar. Zur Validierung dieser Programmcodes wurde eine Messdatensammlung zu einem Inbetriebnahmeexperiment am Block 6 des KKW Kozloduj (WWER-1000/320) erstellt. Die Ergebnisse der durchgeführten Validierungsrechnungen wurden mit den Messwerten aus der Datensammlung verglichen. In den Programmcode DYN3D wurde von den bulgarischen Experten ein vereinfachtes Modell zur Simulation von Querströmungen zwischen den Brennelementen integriert. Dieses Querströmungsmodell ermöglicht es, Prozesse mit asymmetrischen Randbedingungen realistischer zu betrachten. Eine erste Bewertung des implementierten Strömungsmodells erfolgt durch Vergleichsrechnungen zwischen dem modifizierten DYN3D Code und dem Unterkanalanalyse-Code COBRA-4I sowie auf der Grundlage von verfügbaren Messdaten aus dem KKW Kozloduj.

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MOREIRA, Thiago Camargo. "Avaliação da viabilidade técnica do uso do Aço Inoxidável Martensítico 11.3/4Cr-3/4Mo-V em substituição ao Revestimento Duro de CoCr na fabricação de componentes de Turbinas à Vapor." reponame:Repositório Institucional da UNIFEI, 2017. http://repositorio.unifei.edu.br:8080/xmlui/handle/123456789/733.

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O Brasil apresenta uma demanda de energia elétrica crescente nas últimas décadas e uma das alternativas para suprir a elevada demanda é o sistema de cogeração de energia, que utiliza em seus ciclos turbinas a vapor. A obtenção de maior eficiência energética depende do aumento da temperatura e pressão de trabalho. As condições de operação de uma turbina a vapor levam a transformações de fases e constituintes do material e que por sua vez alteram as propriedades mecânicas do material. A alta velocidade do vapor na admissão impõe grande desgaste abrasivo e os próprios mecanismos de operação dos componentes levam a necessidade do material em ter uma elevada tenacidade e alta resistência mecânica. Em hastes e cones de válvulas, o material deve possuir elevada resistência ao desgaste abrasivo, além de alta tenacidade, bem como boa resistência à corrosão e à erosão. O aço inoxidável martensítico 11.3/4Cr-3/4Mo-V é empregado nestes componentes e para atender a relação entre elevada resistência a abrasão, elevada tenacidade e alta resistência mecânica, lança-se mão da aplicação dos revestimentos duros de CoCr, aplicado pelo processo de plasma por arco transferido. O revestimento duro de CoCr é importado, o que eleva o custo do componente e consequentemente torna o produto final menos competitivo. Neste sentido, há necessidade de estudos e pesquisas visando à redução de custos sem perda de funcionalidade dos componentes. Foi avaliada a viabilidade técnica de endurecimento do aço inoxidável martensítico 11 3/4Cr-3/4Mo-V por têmpera e revenido em substituição ao recobrimento duro de CoCr. O aço inoxidável martensítico 11 3/4Cr-3/4Mo-V foi caracterizado nas seguintes condições: conforme recebido, com revestimento duro de CoCr e termicamente tratado e simulado sob condição de operação na temperatura de 550 °C por 1000h. A resistência a abrasão do aço inoxidável martensítico 11.3/4Cr-3/4Mo-V termicamente tratado é superior a do aço revestido com revestimento duro de CoCr. A tenacidade e a dureza do aço inoxidável martensítico 11.3/4Cr-3/4Mo-V termicamente tratado e simulado sob condição de operação, é inferior quando comparado com o aço inoxidável martensítico 11.3/4Cr-3/4Mo-V conforme recebido (laminado a quente e recozido).

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Lelis, Carini Aparecida. "Caracterização físico-química da interação intermolecular entre Vermelho 40 ou Vermelho Ponceau 4R e albumina do soro bovino." Universidade Federal de Viçosa, 2015. http://www.locus.ufv.br/handle/123456789/6700.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Corantes alimentícios são aditivos utilizados em alimentos com importância para a aparência e aceitabilidade do produto. A distribuição uniforme dos corantes nos sistemas alimentícios pode ser uma indicação de interações e formação de complexos entre os corantes e um ou mais ligantes existente na matriz alimentícia. O presente trabalho teve como objetivo estudar a nível molecular os mecanismos envolvidos na interação entre os corantes alimentícios (vermelho 40 (V40) e vermelho ponceau 4R (VP 4R)) e a proteína (albumina do soro bovino (BSA)) em diferentes condições de força iônica, pH e temperatura. Os mecanismos envolvidos na interação entre os corantes e a proteína foram investigados utilizando técnicas altamente sensíveis e eficazes como fluorescência, nanocalorimetria de titulação isotérmica, tensão interfacial e coeficiente de difusão. Resultados de fluorescência mostraram que a intensidade de fluorescência da BSA diminuiu à medida que as concentrações de V40 e VP 4R aumentaram. O mecanismo de extinção da fluorescência foi classificado como estático, havendo portanto, a formação de complexos entre a proteína e os corantes em todas as condições termodinâmicas estudadas. Além disso, a variação de energia livre de Gibbs de complexação foi negativa, sendo regida entalpica ou entropicamente dependendo das condições termodinâmicas. A análise do coeficiente de difusão (CD) dos corantes na presença de concentrações crescentes do biopolímero também demonstrou a formação de complexo entre os corantes e a BSA, visto que os CDs de ambos os corantes diminuíram na presença da proteína. Adicionalmente, a porcentagem de moléculas de corantes ligadas à BSA foi maior na presença de eletrólitos nos pHs 5,0 e 7,4. Medidas de tensão interfacial mostraram que os complexos BSA%corante possuem atividade superficial uma vez que houve redução na tensão interfacial água/ar à medida que a concentração de corante aumentou. A partir da inflexão das curvas de tensão interfacial no equilíbrio termodinâmico versus a concentração de corante foi possível determinar a estequiometria da complexação com valores semelhantes aos obtidos nos experimentos de fluorescência. Experimentos de nanocalorimetria de titulação isotérmica permitiram a determinação da variação da entalpia aparente de interação (∆H int%apar)entre corante e proteína. Os valores obtidos foram diferentes daqueles calculados pela aproximação de van’t Hoff a partir dos experimentos fluorimétricos e demonstraram complexação regida pela entalpia ou pela entropia dependendo das condições termodinâmicas do sistema. Além disso, a conformação da BSA influenciou nas energias obtidas pela análise de calorimetria. Apesar dos corantes apresentarem estruturas químicas similares, a presença de um anel benzênico e um grupo sulfito a mais no VP4R levou a diferenças consideráveis nos parâmetros termodinâmicos de interação com a BSA comparado com o V40, uma vez que o V40 interage na região hidrofóbica da proteína e o VP4R na superfície. Este estudo contribui para o conhecimento em nível molecular da interação entre a BSA e corantes sintéticos em condições de pH, força iônica e temperatura encontradas em matrizes alimentícias e no sangue.
Food dyes are often used to improve food acceptance and appearance. Uniform food dye distribution in food can be an indication intermolecular interactions and formation of complexes between colorants and other molecules. The present work aimed to study in molecular level the mechanisms involved in bovine serum albumin (BSA) and food dyes, allura red (AR) and ponceau 4R (P4R) at different pH, temperature and ionic force. Fluorimetric spectra analyses showed that BSA fluorescence reduced as AR or P4R concentrations increased. Quenching mechanism of complexation was classified as static quenching, indicating formation BSA%colorant complex in all thermodynamic studied conditions. In addition, the Gibbs free energy change was negative, being complexation driven by enthalpy or entropy depending on thermodynamic conditions. The analyses of colorant diffusion coefficient (DC) in the presence of increasing concentrations of biopolymer also demonstrated BSA%colorant interaction since DCs reduced in the presence of protein. Addionally, the percentage of food dye molecules bound to BSA was higher in the presence of electrolyte at pH 5.0 and 7.4. Interfacial tension (IT) measurements showed that BSA%colorant complexes have surface activity because IT values of water%air interface reduced as colorant concentration increased. Also, by inflexion in the curves of IT at thermodynamic equilibrium versus food dye concentration, complexation stoichiometry was determined with similar values to those obtained by fluorimetric measurements. Isothermal titration calorimetry (ITC) experiments provided the apparent interaction enthalpy change (∆app%intH) for BSA%colorant interaction. Values determined by calorimetry were different from those calculated by van’t Hoff approximation from fluorescence data, and demonstrating that complexation was driven by enthalpy or entropy depending on thermodynamic conditions of the systems. In addition, BSA conformation influenced energy found in calorimetric analyses. Despite of both colorants show similar chemical structures, the presence of one more benzenic ring and sulphide group in P4R leaded to considerable differences on thermodynamic parameters of interaction with BSA compared to AR. This work contributes to knowledge at molecular level of interaction between BSA and synthetic food dyes in food and blood conditions.

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47

Garbergs, Hanna. "Hinder vid kommersialisering av teknologier : En fallstudie kring förflyttning av teknologi från universitetsmiljö till företagsmiljö." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-155477.

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Det som är unikt i en akademisk miljö passar inte alltid in i en företagsmiljö. Därför kan det uppstå hinder då teknologier ska kommersialiseras. Syftet med den här uppsatsen är att undersöka hur dessa hinder kan se ut. Med hjälp av en tillämpad 4R-modell har de olika produkter, faciliteter och utrustning, affärsrelationer och organisatoriska enheter som påverkar kommersialiseringen av en teknologi kunnat kartläggas och utifrån detta har hinder identifierats. En fallstudie har genomförts där en teknologi har förflyttats från universitets- till företagsmiljö. Några av de hinder som har identifierats är att då en teknologi ska börja användas i stor skala kan ny utrustning få lov att utformas och göras tillgänglig och nya logistiska nät kan behöva sättas upp för att säkerställa försörjningen av kritiska råvaror. För att kunna dra generella slutsatser behöver vidare forskning genomföras.

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48

Karlsson, Emil. "Ambulanspersonals lärprocesser i hanteringen av hot- och våldssituationer : Riskfaktorer, lärprocesser och utvecklingsbehov inom prehospital vård i två svenska län." Thesis, Linköpings universitet, Institutionen för beteendevetenskap och lärande, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177998.

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Zobel, Lydia [Verfasser]. "Die Funktion von intrazerebralen Makrophagen beim Staphylococcus aureus-induzierten Hirnabszess im Kontext der IL-4R-abhängigen Aktivierung / Lydia Zobel." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2017. http://d-nb.info/1133074359/34.

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Stupfel, Marine. "Reconnaissance de surfaces de protéines par des foldamères aromatiques." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14189/document.

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Les interactions protéine-protéine jouent un rôle primordial dans de nombreux processus biologiques. L’importance de ces interactions a suscité le développement de nouvelles approches thérapeutiques qui ciblent ces complexes protéiques. Nous nous proposons d’inhiber ces interactions en élaborant une stratégie de reconnaissance de surfaces de protéines par des molécules synthétiques de taille intermédiaire, les foldamères d’oligoquinoline. Ces composés se replient en des structures hélicoïdales stables dont chaque élément constitutif peut être fonctionnalisé pour permettre des propriétés de reconnaissance de surface de protéine.Afin de valider ce concept, l’interaction entre l’anhydrase carbonique humaine de type II (HCAII) et son inhibiteur N-benzyl-4-sulphamoylbenzamide (SBB) a été sélectionnée comme système modèle. Plusieurs étapes de synthèse ont permis de concevoir de nouveaux foldamères capables de former un complexe avec l’enzyme par l’intermédiaire de l’inhibiteur SBB et d’un espaceur approprié. Chaque complexe protéine-foldamère a été co-cristallisé et l’affinité des interactions a été caractérisée par dichroïsme circulaire induit et par résonance plasmonique de surface. Ce concept a ensuite été appliqué à une interaction protéine-protéine d’intérêt thérapeutique, le complexe IL-4/IL-4R, dans le cadre du programme européenFOLDAPPI (FP7-PEOPLE-IAPP-2008)
Protein-protein interactions play key roles in many biological processes as well as in many diseases. The importance of these interactions has led to the development of new therapeutic approaches that target protein interfaces. We have developed a protein surface recognition strategy to inhibit protein-protein interactions by using intermediate size organicmolecules called oligoquino line foldamers, that result in very stable and well defined helical structures. These helical backbones are used as templates within each building block can be modulated to allow protein surface recognition.In order to validate this concept, the well-characterized interaction between the enzyme human carbonic anhydrase II (HCAII) and its N-benzyl-4-sulphamoylbenzamide (SBB) inhibitor was selected as a model system. Multi-steps synthesis allowed functionalization of new foldamers able to bind to the enzyme through the SBB inhibitor attached by a spacer.Each foldamer–protein complex was cocrystallized and the affinity of the interactions was assayed using both induced circular dichroïsm and surface plasmon resonance. The concept of using a foldamer against protein-protein interaction was then applied to a protein complex of therapeutic interest, IL-4/IL-4R, within the European FOLDAPPI program (FP7-PEOPLEIAPP- 2008)

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