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Berggren, Mirja. "OPAC på Internet : möjligheter för sökning på skönlitteratur. En jämförelse mellan en bokhandel på Internet och fem OPACs." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20741.
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The aim of this master thesis is to investigate how the OPACs Online Public Access Catalogue used by public libraries have adapted the features and possibilities offered by online catalogues, for the purpose of searching for fiction. This is done by comparing five OPACs to Amazon.com, an online bookstore. The questions investigated are: Have the OPACs developed from the principles of the card catalogue and adapted to the features and possibilities offered by online catalogues, when searching for fiction? Can the library catalogue provide the same features as Amazon.com, when searching for fiction? How do the OPACs use the resources that online catalogues provide when searching for fiction, compared with Amazon.com? The thesis is based on two qualitative studies. The first study presents five OPACs from different library systems and examines which features they have in common with Amazon.com. The second study examines how five public libraries use the potential features of their OPACs. The OPACs have started to develop features and possibilities that online catalogues provide but they have not completely abandoned the principles of the card catalogues. Most OPACs still only allow keyword searches and do not support browsing through genres and subjects. They do not offer a designated area for fictional search only. So far the libraries have not developed the OPACs potential to include additional information such as covers and reviews. The users have some possibilities to interact with the OPACs to make them more useful for their personal needs. Nr 63 Maria Broman: Ungdomar och nättidningsläsning En kvalitativ studie av nio gymnasieungdomars förhållande till dagstidningar på Internet Adolescents and Net Newspaper Reading A Qualitative Study of Nine High School Students' Relations to Newspapers on the Internet This Master Thesis deals with nine high school students' relations to, and reading of, newspapers on the Internet. In the context of the Internet and net newspapers, adolescents represent a group that is particularly interesting to study. For instance, they have a positive attitude towards Net newspapers and they are the first generation to grow up with the Internet and thereby associated technology. Moreover, mass media is an important part of young peoples' daily lives. A qualitative approach was used, resulting in interviews with four girls and five boys. The study reveals that the adolescents visit a newspaper site primarily to read the news and not to utilise the interactive services available. Highly valued aspects of Net newspapers are that they are free of charge and easily accessible from home. Nevertheless, the informants almost exclusively read Aftonbladet, the singularly most popular alternative on the Net. Furthermore, it was found that Internet newspaper reading has a natural place in the adolescents' lives for the time being, a habit connected to other activities such as surfing the Net and practising sports and music. However, traditional print newspapers remain the basis for newspaper reading, as the Internet is still seen as a complement. No clear evidence of continued long-term Net newspaper reading emerged, and the development will likely depend on the adolescents' personal future situations as well as the technological progress in general.Uppsatsnivå: D
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Greifeneder, Elke. "Effektivität und Effizienz von Online-Hilfesystemen in deutschen Universitäts-OPACs." kostenfrei, 2007. http://edoc.hu-berlin.de/oa/books/reUIxmZgrpGw/PDF/27K5h8XoLOcfo.pdf.
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Merget, Iris. "Die Gestaltung von Benutzerschnittstellen mittels Online-Hilfefunktionen in OPACs : Stand, Trends, Perspektiven /." Saarbrücken : Univ. des Saarlandes, 1993. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=018907728&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Slack, Frances Elisabeth. "OPACs : using enhanced transaction logs to achieve more effective online help for subject searching." Thesis, Manchester Metropolitan University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293574.
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Tinker, Amanda Jayne. "Deriving and applying facet views of the Dewey Decimal Classification Scheme to enhance subject searching in library OPACs." Thesis, University of Huddersfield, 2005. http://eprints.hud.ac.uk/id/eprint/7482/.
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Classification is a fundamental tool in the organisation of any library collection for effective information retrieval. Several classifications exist, yet the pioneering Dewey Decimal Classification (DDC) still constitutes the most widely used scheme and international de facto standard. Although once used for the dual purpose of physical organisation and subject retrieval in the printed library catalogue, library classification is now relegated to a singular role of shelf location. Numerous studies have highlighted the problem of subject access in library online public access catalogues (OPACs). The library OPAC has changed relatively little since its inception, designed to find what is already known, not discover and explore. This research aims to enhance OPAC subject searching by deriving facets of the DDC and populating these with a library collection for display at a View-based searching OPAC interface. A novel method is devised that enables the automatic deconstruction of complex DDC notations into their component facets. Identifying facets based upon embedded notational components reveals alternative, multidimensional subject arrangements of a library collection and resolves the problem of disciplinary scatter. The extent to which the derived facets enhance users' subject searching perceptions and activities at the OPAC interface is evaluated in a small-scale usability study. The results demonstrate the successful derivation of four fundamental facets (Reference Type, Person Type, Time and Geographic Place). Such facet derivation and deconstruction of Dewey notations is recognised as a complex process, owing to the lack of a uniform notation, notational re-use and the need for distinct facet indicators to delineate facet boundaries. The results of the preliminary usability study indicate that users are receptive to facet-based searching and that the View-based searching system performs equally as well as a current form fill-in interface and, in some cases, provides enhanced benefits. It is concluded that further exploration of facet-based searching is clearly warranted and suggestions for future research are made.
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La, Barre Kathryn. "Faceted navigation and browsing features in new OPACs: A more robust solution to problems of information seekers? (extended abstract)." dLIST, 2007. http://hdl.handle.net/10150/106157.
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In November, 2005, James Billington, the Librarian of Congress, proposed the creation of a “World Digital Library” of manuscripts and multimedia materials in order to “bring together online, rare and unique cultural materials.” Google became the first private sector partner for this project with a pledge of 3 million dollars (http://www.loc.gov/today/pr/2005/05- 250.html). One month later, the Bibliographic Services Task Force of the University of California Libraries released a report: Rethinking how we provide bibliographic services for the University of California. (Bibliographic Services Task Force, 2005). Key proposals included the necessity of enhancing search and retrieval, redesigning the library catalog or OPAC (Online Public Access Catalog), encouraging the adoption of new cataloguing practices, and supporting continuous improvements to digital access. By mid-January, 2006, the tenor of discussion reached fever pitch. On January 12, 2006, the North Carolina State University (NCSU) Library announced the deployment of a revolutionary implementation for their OPAC of Endeca’s ProFind™, which until now had only been used in commercial e-commerce or other business applications. NCSU made the bold claim that “the speed and flexibility of popular online search engines” had now entered the world of the online catalog through the use of faceted navigation and browsing (NCSU, online). A few days later, Indiana University posted A White Paper on the Future of Cataloging at Indiana University which served to identify current trends with direct impact on cataloging operations and defined possible new roles for the online catalog and cataloging staff at Indiana University (Byrd et. al, 2006). The Indiana report was a response to an earlier discussion regarding The Future of Cataloging put forth by Deanna Marcum, Director of Public Service and Collection Management at the Library of Congress (Marcum, 2005). Marcum posed a provocative series of questions and assertions based in part on the Pew Internet and American Life Project study: Counting on the Internet (Horrigan and Rainey, 2005). “[D]o we need to provide detailed cataloging information for digitized materials? Or can we think of Google as the catalog?” Following Marcum’s comments, and the announcement of the “World Digital Library”, the Library of Congress released a commissioned report in March 2006, The changing nature of the catalog and its integration with other discovery tools” (Calhoun, 2006). This report contained blueprints for change to Library of Congress cataloguing processes, advocated integration of the catalog with other discovery tools, included suggestions that the Library of Congress Subject Headings LCSH, long used to support subject access to a variety of cultural objects, be dismantled, and argued that fast access to materials should replace the current standard of full bibliographic records for materials. These arguments were supported by assertions that users seem to prefer the ease of Google over the catalog, and that the proposed changes would place the Library of Congress in a better market position to provide users with the services they want most (Fast and Campbell, 2004; OCLC, 2002). The ensuing debates served to crystallize the intersection and convergence of the traditional missions of the Libraries, Archives and Museum (LAM) communities to provide description, control and access to informational and cultural objects. One consistent theme emerged: What competencies and roles can each community bring to bear upon discussions of digitization, access and discovery, and provide solutions for user needs? The library community had a ready answer. Originally designed to provide inventory, acquisitions and circulation support for library staff, the modern library catalog was designed according to a set of principles and objectives as described by Charles Ammi Cutter in 1876. These principles and objectives underpin the core competency of the library community to create bibliographic records designed to assist users in the following tasks: to find (by author, title and subject), and to identify, select and obtain material that is of interest to them. Discussions about the aims of the catalog are not new and have been ongoing since the early 1970s when the earliest forays of the catalog into the digital age began (Cochrane, 1978). The role played by metadata (i.e. bibliographic records assembled in catalogs), as well as the central importance of search and retrieval mechanisms have long been central players in proposed solutions to providing better services to users. Thus, the suggestions of staff at the Library of Congress, that digitization is tantamount to access, and that search engines, like Google, may supplant the catalog as the chief means of access to cultural and informational materials, have galvanized action throughout the library and information science community. It is critical that any discussions and recommended solutions maintain a holistic view of the principles and objectives of the catalog. The actions and continuing discussions that resulted from these developments drew heavily from several sources, including the experiences of the LAM community with the creation of metadata standards, Web 2.0 applications that make data work harder, more accessible and consolidated, the appeal of folksonomy and social classification, and the importance of leveraging rather than abandoning legacy access systems in a time of spiraling costs and decreasing budgets. For archived discussions of these issues see: lNGC4LIB listserv (Next Generation Catalogs for Libraries http://listserv.nd.edu/archives/ngc4lib.html) and Web4LIB discussion list (http://lists.webjunction.org/web4lib/). Another valuable source is Lorcan Dempsey’s blog, Of libraries, services and networks (http://orweblog.oclc.org/). To leverage some legacy subject access systems it is proposed that more (not less) should be done to process these data, and corresponding authority files (e.g. thesaurus files) in order to use the faceted navigation and browsing features of new online search engines to best advantage. An ongoing research proposal will be described in brief, concentrating on the second goal of a project which plans to develop an integrated conceptual framework which could serve all designers working on information access and discovery systems. A framework for critical analysis of needed and missing features that is grounded in traditional principles, borne out by practice (Cutter, 1976; La Barre, 2006; Ranganathan, 1962) and which builds on feature analysis protocols for early OPACs is urgently needed (Cochrane, 1978; Hildreth, 1995). Further, another analysis of the sufficiency of current data preparation is long overdue (Anderson and Peréz-Carballo, 2005). This position paper builds on La Barre (2006, unpublished dissertation) which studied faceted browsing and navigation in websites, using wireframe analysis. This research uncovered features needed for digital library OPAC design. Building on JISC and Sparks work, a future study will focus on the information seeking research academics and the information seekers, rather than the general public, or the overstudied undergraduate user, thus rounding out the work of others cited by Marcum, Kuhlthau, etc.
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Afonso, Maria Gorete Barroso. "Para uma biblioteca do conhecimento: Aplicações da Web semântica à organização da informação em catálogos de acesso público." Doctoral thesis, Universidade Portucalense, 2015. http://hdl.handle.net/11328/1373.
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Tese de Doutoramento em Educação na Área de Especialização em Educação e Bibliotecas.A recuperação da informação contida nos Web OPAC (Online public access catalog) das bibliotecas enfrenta sérias limitações provocadas pelas características próprias dos instrumentos de organização e recuperação utilizados. Índices, thesauri e classificações tradicionalmente aplicados aos registos catalográficos apenas permitem recuperar o conteúdo bibliográfico ou documental existente, alheando-se da possibilidade de que essa recuperação possibilite, desde logo, um acesso a conhecimento expandido através das mesmas palavras-chave escolhidas para a pesquisa num dado catálogo. No entanto, a Web semântica permite a transformação destes modelos de acesso ao conhecimento em modelos de ontologias de nível superior. Surge assim a questão que leva ao desenvolvimento da presente tese de doutoramento, e que procura, em primeiro lugar, indagar sobre os mecanismos de representação do conhecimento mais adequados às bibliotecas públicas e, subsequentemente, sobre a possibilidade de desenvolver um produto específico aplicável a uma biblioteca pública em concreto. Apresentando como objetivo final o desenvolvimento de um produto tecnológico com as caraterísticas acima apontadas, a investigação aplicou uma metodologia de design science que levou à concretização de um protótipo aplicado e testado preliminarmente no catálogo do Fundo Local da Biblioteca Municipal de Montalegre. A metodologia adotada, cíclica e interativa, envolveu a cooperação interdisciplinar entre os campos da Ciência da Informação, da Informática e Computação e da Educação. O desenvolvimento do protótipo permitiu, numa primeira fase, transformar a informação encerrada no catálogo em linha da Rede Concelhia de Bibliotecas de Montalegre (RCBM) e cruzar devidamente essa informação com outras fontes, como por exemplo a DBpedia, num formato adequado à Web semântica, representado por triplos RDF (Resource Description Framework) que estabelecem relações definidas em ontologias, entre os recursos oriundos de diferentes fontes. Numa segunda fase, esses dados abertos e ligados, com identificadores únicos e universais (URIs), ficaram disponíveis para exploração a partir de uma plataforma de código aberto CKAN (Comprehensive Knowledge Archive Network) usada para o efeito; esta plataforma permite que um fluxo de Título: Para uma biblioteca do conhecimento: Apl icações da Web semânt ica à organização da informação em catálogos de acesso públ ico transformação em conhecimento fique disponível para ser explorado e apropriado por terceiros. Os resultados demonstraram as potencialidades do protótipo, tendo sido comprovada uma representação adequada através de um pequeno conjunto de pesquisas SPARQL (Protocol and RDF Query Language) que cruzam os dados do catálogo (em RDF) com os dados da DBpedia. Assim, uma pesquisa no OPAC sobre um determinado autor, permite aceder, não só às obras desse mesmo autor detidas ou acessíveis através da biblioteca, mas também a um conjunto de informação biobibliográfica, estudos, representações de imagens, etc., disponível na Internet e que concretiza o objetivo de expandir o conhecimento do utilizador através de uma simples pesquisa num catálogo. Todo o trabalho está documentado e é facilmente replicável por qualquer outra biblioteca que tenha um catálogo num formato da família MARC (Machine Readable Cataloging). Conclui-se pois que, não só a Web semântica permite tornar mais eficazes os serviços de recuperação da informação das bibliotecas, como essa possibilidade é replicável e possibilita uma maior cooperação em rede entre bibliotecas de uma mesma região, ou até nacionais e internacionais.
The retrieval of information contained in web OPACs (Online public access catalog) libraries face serious limitations caused by the characteristics of the organization and retrieval tools used. Indexes, thesauri and classifications traditionally applied to cataloging registers only enable to recover the existing bibliographic or documentary content, alienating the possibility that this recovery enable, firstly, access to expanded knowledge through the same keywords chosen for research in a given catalog. However, the semantic web allows the transformation of these access models to knowledge in models of top-level ontologies. This raises the question that leads to the development of this PhD thesis, and seeking, first, to inquire into the knowledge representation mechanisms best suited to public libraries and, subsequently, on the possibility of developing a specific product applicable to a public library in concrete. Featuring the ultimate goal the development of a technological product with the features outlined above, research applied a design science methodology that led to the realization of a prototype tested preliminarily on Local Fund catalog of Montalegre Municipal Library. The methodology adopted, cyclical and interactive, involved the interdisciplinary cooperation between the fields of Information, Informatics and Computer Science and Education. The development of the prototype allowed, initially, the transformation of the information contained in the OPAC Web of District Council Library Network of Montalegre and properly cross with other sources, such as DBpedia, in an appropriate format to the semantic web, represented by triples RDF (Resource Description Framework) establishing relationships defined in ontologies, between resources from different sources. Therefore, these open and linked data with unique and universal identifiers (Uniform Resource Identifier - URIs), would be available for exploitation from an open-source platform CKAN (Comprehensive Knowledge Archive Network) used for this purpose; this platform enable that a flow of transformation into knowledge became available to be explored and appropriated by others. The results demonstrated the potential of the prototype, with adequate representation been proven through a small set of SPARQL (Protocol and RDF Query Language) research that intersect catalog data (RDF) with data from DBpedia. Thus, a search on OPAC about a particular author, allows access not only to the works of the same author detained or accessible by the library, but also to a set of biobibliographic information, studies, image representations, etc., available on the Internet and concretize the objective of expanding the knowledge of the user through a simple search in a catalog. All work is documented and is easily replicable in any other library that has a catalog in a MARC (Machine Readable Cataloging) family format. It is therefore concluded that, not only the semantic web allows increase the effectiveness of information retrieval services of libraries, as this possibility is replicable and enables greater network cooperation between libraries in the same region, or even national and international.
Orientação: Prof. Doutora Manuela Barreto Nunes e Prof. Doutor António Manuel Andrade.
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Barret, Beverley, and n/a. "Users and an online catalogue : an evaluation of the OPAC at the Dixson Library, University of New England." University of Canberra. Information, Language & Culture Studies, 1989. http://erl.canberra.edu.au./public/adt-AUC20060607.162838.
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This thesis reports on a study undertaken at the Dixson Library, University of New
England. The purpose of the study was to develop an understanding of users of online
public access catalogues (OPACs). The understanding gained from the study will assist
in the development of improvements to the Library's OPAC, and increase user ability to
access information from the OPAC. The study replicated the user questionnaire of the
Online Patron Access Project, sponsored by the Council on Library Resources (CLR) in
1981/83. The questionnaire was modified slightly to suit conditions at the Dixson
Library.
The study addressed nine research questions relating to the users, their reactions,
attitudes, experiences and problems. The user task and their suggestions for
improvement were also addressed. The study formally tested three propositions between
the variables user task, success and attitudes in relation to OPAC users.
The findings show the analysis of the responses for the population as a whole, and,
where relevant, for eight groups of student respondents based on their academic
affiliation. The student population was of particular importance because of the
preponderance of external students at the University of New England. The differences in
the findings between the groups of students were discussed, and where possible,
explained. The three formal propositions were tested by carrying out Chi square tests for
the values of each variable. Nine significant relationships were found.
Comparisons were made between the Dixson Library findings and those of the CLR
study. Recommendations and conclusions were drawn from the study, including areas
for further research.
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Weimar, Alexander. "Inhaltserschließung und OPAC-Retrieval am Beispiel des OPAC der Universitätsbibliothek Heidelberg." [S.l. : s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11611965.
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Zhao, Qibin. "Oscillatory shearing in polymer opals." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709151.
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Lindmark, Åke. "OPAC - på Märsta folkbibliotek." Thesis, Uppsala universitet, Institutionen för ABM, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-224625.
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The purpose of this Bachelor thesis is to examine how user-friendly the OPAC of the Märsta public library is considered to be.Theoretical basis are HCI and Allwoods definition of usability. Issues are: Is the OPAC suited to its task? Is the OPAC user-friendly? How well does a user accept the OPAC? and What degree of competence is shown by users of the OPAC? The source material consists of six interviews in the form of .avi files. The method I have chosen is qualitative semi-structured interview form. The result is that, based on Carl Martin Allwood’s defini-tion and with exception for the using of help-resources, the usability of Märsta’s library OPAC can be considered less good.
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Campos, A. Patricio. "Opas norteamericanas en Chile." Tesis, Universidad de Chile, 2003. http://repositorio.uchile.cl/handle/2250/108210.
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Este seminario de título nació con el objetivo de investigar el “por qué las
compañías norteamericanas, cuando lanzan una oferta pública de adquisición sobre
alguna compañía chilena, la hacen por el 100% de ésta, o casi el 100%, sin embargo, los
españoles o chilenos, cuando lanzan una oferta pública de adquisición, solo desean
obtener el 51 % de la propiedad, es decir, tener el control de la compañía”
Esta interrogante es difícil de responder, debido a que no se encuentra argumento
teórico a esta cuestión, además, ¿por qué solo los norteamericanos lo hacen? ¿qué tienen de
espaciales sus compañías o su legislación?
Se llegó a la conclusión, de que la regulación norteamericana protege al accionista
minoritario de las compañías que están siendo objeto de la oferta, pero no solo a las
compañías objetivo en EEUU, sino en cualquier país. Si la compañía norteamericana no
respeta su propia normativa porque esta comprado una compañía chilena en suelo chileno,
los minoritarios chilenos pueden demandarlos en sus propios tribunales. La legislación
española solo rige en dicho país, pero si sus compañías salen al extranjero, estas se rigen
por las leyes locales.
Como el mercado de valores chileno es altamente atomizado, si los 2 accionistas
mayoritarios de una compañía deciden no participar de la oferta, la probabilidad de fracaso
de ésta bordea el 100%, y si tan solo el mayoritario no quiere participar, la probabilidad de
fracaso sigue siendo muy alta.
Los españoles y chilenos, antes de lanzar una oferta pública de adquisición, tranzan
paquetes accionarios con los controladores y luego lanzan una oferta por el porcentaje
faltante para el 51%, como los norteamericanos no pueden comprar paquetes accionarios,
éstos deben ofrecer comprar a todos los accionistas que estén dispuestos a vender, por ello
es que lanzan ofertas por prácticamente la totalidad de la propiedad, en los casos analizados
en este seminario, llagan a poseer más del 98% de la propiedad.
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Fuentes, Vega Marcela Alejandra. "OPAS. Teoría y evidencia." Tesis, Universidad de Chile, 2007. http://repositorio.uchile.cl/handle/2250/108442.
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El Problema de Agencia se define como una divergencia de intereses entre el
Agente (insiders) y el Principal (outsiders) (*), es decir, el agente como maximizador,
buscará el beneficio propio antes que el de la compañía. El Gobierno Corporativo es un
concepto que tiene relación con la forma en que las empresas son dirigidas y
controladas, en el que se incluye el conflicto mencionado.
La necesidad de contar con un mercado de capitales que proteja
adecuadamente a los accionistas minoritarios y permita aumentar la liquidez y
transparencia del mercado junto con disminuir el costo de financiamiento de las
empresas, han llevado al gobierno de Chile a la elaboración de la nueva Ley de OPAS,
promulgada en Diciembre del año 2000.
Dicha ley permite crear mejores Gobiernos Corporativos, estableciendo una
mejor calidad de información entregada por las empresas, conformar comités de
auditoría al interior de las sociedades anónimas abiertas, regular las relaciones entre
partes relacionadas, mejorar los derechos de los tenedores de ADRs, entre otros.
En Chile, se tiene que la mayoría de las sociedades anónimas son controladas
por un solo accionista, familia o grupo económico. El problema, por lo tanto, se da entre
los intereses del accionista controlador y los inversionistas (accionistas minoritarios,
acreedores). Los conflictos respecto a la asignación de valor corporativo se pueden
resumir como sigue: Extracción de valor de la Compañía y Premio por control.
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Aromaa, Henri. "UA OPAC OK? En kvalitativ undersökning av Uppsala stadsbiblioteks OPAC ur ett användarperspektiv." Thesis, Uppsala University, Department of ALM, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-101747.
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Ladeira, Isabel Cristina Gomes dos Santos. "Desenvolvimento de um vidrado opaco brilhante." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/2269.
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Mestrado em Engenharia de MateriaisCom o presente trabalho, pretendeu-se avaliar a viabilidade técnica e económica da produção dum vidrado cerâmico opaco brilhante, que permitisse substituir o actualmente utilizado na produção de revestimento por bicozedura rápida. A formulação do vidrado teve em vista não só uma melhoria significativa de qualidade mas também, a obtenção de um produto cerâmico para revestimento, economicamente vantajoso. O estudo foi realizado em particular para o caso de revestimentos conformados por prensagem, com ciclos de bicozedura rápidos. As características de suporte e os ciclos de cozedura, quer do suporte quer do vidrado, mantiveram-se constantes. A formulação do novo vidrado obedeceu aos seguintes requisitos: 1. Características reológicas adequadas para aplicação do vidrado por cortina; 2. Vidrado adaptado ao ciclo de bicozedura rápida com uma temperatura máxima entre 980ºC e1000ºC durante 25min a 30min; 3. Coeficiente de dilatação adaptado ao suporte cerâmico; 4. Grau de brancura com L=90, no espaço de cores Lab; 5. Superfície com boas características em termos de textura. Os resultados obtidos permitiram formular uma composição de vidrado tecnicamente aprovada em ensaio industrial, que substituiu o vidrado de referência na unidade de produção, com vantagens ao nível da qualidade final do produto e financeiras para a empresa. ABSTRACT: The scope of the present work was to evaluate the feasibility of the production of a new opaque ceramic glaze to be used in two steps fast firing tile ceramic production. With the use of the new glaze composition an improved technical quality and an economic benefit of the final product should be achieved. The glaze should fulfill the following requirements: 1. Rheological properties of the glaze suspensions appropriate for their application on tiles surface; 2. Be suitable to be used in two steps fast firing at 980ºC-1000ºC during 25 - 30 min; 3. Dilatometric compatibility with the ceramic tile; 4. Colour degree L = 90 in the (Lab) space; 5. Good superficial texture. The obtained results allowed to formulate a glaze composition industrially approved. Such composition improved the final quality of the glazed tile and the economic profits to the industry.
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Phillips, Katherine Reece. "Sol-Gel Chemistry of Inverse Opals." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493452.
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Controlling nano to microscale structuration enables one to alter a material’s optical, wetting, mechanical, and chemical properties. Structuration on this scale can be formed from spherical building blocks; in particular, monodisperse, spherical colloids assemble into crystals that can be used to template an ordered, porous structure known as an inverse opal. The structure’s porosity and periodicity provide control over both light (photonic effects) and fluid flow (wetting effects). Controlling the composition allows chemical functionality to be added to the ordered, porous structure. Inverse opals are widely used in many applications that take advantage of these properties, including optical, wetting, sensing, catalytic, and electrode applications; however, high quality structures are necessary to maintain consistent properties. Many of their properties stem from the structure itself, so controlling inverse opals’ structure (including the local composition) provides the ability to control their properties, with the potential to improve some applications and potentially enable additional ones.
This thesis explores how molecular precursors can be used to control colloidal assembly and therefore alter the optical and wetting properties of high quality inverse opals. Using a bio-inspired approach, highly ordered, crack-free, silica inverse opals can be grown by co-assembling the colloidal template with a sol-gel matrix precursor using evaporation-induced self-assembly. Using sol-gel chemistry, the size, shape, and charge of the precursor can be controlled, which can be used to tune the colloidal assembly process. Here, we use the sol-gel chemistry of the precursors to control both the morphology and composition of these photonic structures.
In particular, temperature-induced condensation of the silica sol-gel matrix alters the shape of an inverse opal’s pores (Chapter 2), and silica and titania precursors can be mixed to make hybrid oxide structures (Chapter 3). Additionally, rationally designed precursors enable the fabrication of crack-free inverse opals in materials beyond silica, which we show for titania as a proof-of-concept (Chapter 4). By controlling the structure and composition with sol-gel chemistry, we can tailor both the optical and wetting properties, as discussed in the second part of each chapter; these properties have important effects for the various applications. In this way, sol-gel chemistry can be used to assemble inverse opals with complex functionality.Chemistry and Chemical Biology
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Aryal, Durga Prasad. "Theory and modelling of functional photonic opals." Thesis, University of Surrey, 2007. http://epubs.surrey.ac.uk/843026/.
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In this dissertation, we explore the optical properties of various opal-based photonic crystal structures. Particular attention is paid to the tunability of the optical properties, especially the photonic band gaps (PBG), with the motivation to apply these opal-based photonic crystals (PCs) to the design of functional surfaces and switchable windows. After reviewing the basic optical properties of inverse opals, two different types of opal-based photonic crystals, namely the Double-Shell Photonic Crystal (DSPC) and the Double-Inverse-Opal Photonic Crystal (DIOPC) are successively introduced and throroughly studied. In the DSPC structure, each sphere in the periodic photonic crystal structure is made of a hollow core, along with an accompanying shell of a different dielectric material; the resulting spherical structure is embedded in a high-index dielectric background. By contrast, the DIOPC is designed with an inverse opal backbone, in which the air pores are partially filled with a dielectric core sphere. In our work, two types of photonic bandgap tuning are examined, namely geometrical/positional, and tailoring of the materials' properties. A comparison of the proposed structures regarding their potential for experimental realization is also performed. Considering that the air shells in the DIOPC structure allow for relative movement of the dielectric cores inside them, we propose and study a completely novel approach to obtain a switchable complete band gap achieved, by shifting the spheres inside the air shells. After demonstrating that the complete photonic band gap is open for certain core sphere positions and is closed for others, we propose ways to optimise this new switching process. This optimisation leads to a maximum switching of the complete photonic band gap of 3.5%.Taking into account that in real-world situations, all photonic crystals possess a certain amount of structural imperfections, the last step of the study concerns the effects of disorder on the optical properties of opal-based photonic crystals. After discussing different types of disorder, in both the backbone and the core spheres, we conclude that to retain a complete PEG in the DIOPC structure, and thus the switching process, a maximum backbone disorder of 1 % should be reached experimentally, whereas the disorder on the core sphere does not affect the PEG as much. These investigations have been performed using both a plane-wave expansion method and a finite-difference time-domain method.
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Råde, Trulsa. "En usabilityutvärdering av Umeå Universitetsbiblioteks OPAC." Thesis, Umeå universitet, Sociologiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-102680.
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This is a heuristic evaluation of Umeå university library’s Online Public Access Catalog (OPAC). It makes use of four of Nielsen’s ten heuristics, flexibility and efficiency to use, match between the system and real world, visibility of system status, and aesthetic and minimalist design. The evaluation was done by having 3 evaluators inspect the interface individually, as per Nielsen’s (1990) recommendation of 3-5 evaluators. Then a list of all identified usability problems was compiled and the evaluators rated the severity of these on a scale of 0 - 4. The heuristic method is a well-established evaluation method, developed by Jakob Nielsen. It has been used in evaluations such as Yushiana and Rani’s Heuristic evaluation of interface usability for a web‐based OPAC (2007), and has been compared to other methods in studies such as Ahmed’s A comparison of usability techniques for evaluating information retrieval system interfaces (2008). 21 usability problems were identified and rated. This evaluation found that Umeå university library’s OPAC has the most usability problems relating to the heuristic flexibility and efficiency to use. The parts of the OPAC interface with the most usability problems were the advanced and regular search functions. The most pressing issues were the order in which the results of a search were presented, and the lack of information on how to use the advanced search, including how many words that go in each “box” and that Boolean operators could be used. The OPAC did not conform to the two heuristics flexibility and efficiency to use, and match between the system and the real world. It just about fails when it comes to aesthetic and minimalist design. The OPAC does comply with the heuristic visibility of system status.
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Payet, Puccio José Antonio. "OPAs hostiles y medidas de protección." IUS ET VERITAS, 2016. http://repositorio.pucp.edu.pe/index/handle/123456789/123268.
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Rauti, Silvia <1969>. "Gli opac delle biblioteche pubbliche vicentine." Master's Degree Thesis, Università Ca' Foscari Venezia, 2012. http://hdl.handle.net/10579/2029.
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McCarthy, Laura Anne. "South Australian sedimentary opals : evidence for syngenetic deposition /." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09SB/09sbm1234.pdf.
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Sütterlin, Martin. "New inverse hydogel opals as protein responsive sensors." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2014/7017/.
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In this work, the development of temperature- and protein-responsive sensor materials based on biocompatible, inverse hydrogel opals (IHOs) is presented. With these materials, large biomolecules can be specifically recognised and the binding event visualised. The preparation of the IHOs was performed with a template process, for which monodisperse silica particles were vertically deposited onto glass slides as the first step. The obtained colloidal crystals with a thickness of 5 μm displayed opalescent reflections because of the uniform alignment of the colloids.
As a second step, the template was embedded in a matrix consisting of biocompatible, thermoresponsive hydrogels. The comonomers were selected from the family of oligo(ethylene glycol)methacrylates. The monomer solution was injected into a polymerisation mould, which contained the colloidal crystals as a template. The space in-between the template particles was filled with the monomer solution and the hydrogel was cured via UV-polymerisation. The particles were chemically etched, which resulted in a porous inner structure. The uniform alignment of the pores and therefore the opalescent reflection were maintained, so these system were denoted as inverse hydrogel opals. A pore diameter of several hundred nanometres as well as interconnections between the pores should facilitate a diffusion of bigger (bio)molecules, which was always a challenge in the presented systems until now. The copolymer composition was chosen to result in a hydrogel collapse over 35 °C. All hydrogels showed pronounced swelling in water below the critical temperature. The incorporation of a reactive monomer with hydroxyl groups ensured a potential coupling group for the introduction of recognition units for analytes, e.g. proteins.
As a test system, biotin as a recognition unit for avidin was coupled to the IHO via polymer-analogous Steglich esterification. The amount of accessible biotin was quantified with a colorimetric binding assay. When avidin was added to the biotinylated IHO, the wavelength of the opalescent reflection was significantly shifted and therefore the binding event was visualised. This effect is based on the change in swelling behaviour of the hydrogel after binding of the hydrophilic avidin, which is amplified by the thermoresponsive nature of the hydrogel. A swelling or shrinking of the pores induces a change in distance of the crystal planes, which are responsible for the colour of the reflection. With these findings, the possibility of creating sensor materials or additional biomolecules in the size range of avidin is given.In dieser Arbeit wird die Entwicklung von temperatur- und proteinresponsiven Sensormaterialien auf Basis von biokompatiblen, inversen Hydrogelopalen (IHO) vorgestellt, mit welchen die spezifische Erkennung größerer Biomoleküle visuell ausgelesen werden kann. Die Darstellung der IHOs erfolgte mittels Templatverfahren, bei dem im ersten Schritt monodisperse Silicapartikel vertikal auf Objektträger abgeschieden wurden. Die so erhaltenen Kolloidkristalle mit einer Dicke von 5 μm zeigten opaleszente Reflexionen aufgrund der gleichförmigen Anordnung der Partikel. Im zweiten Schritt wurde das Templat in eine Matrix aus biokompatiblen, thermoresponsiven Hydrogelen eingebettet. Die Comonomere wurden aus der Familie der Oligo(ethylenglykol)methacrylate ausgewählt. Zur Synthese des Hydrogels wurde die Monomerlösung in eine Polymerisationsform injiziert, welche die Kolloidkristalle als Templat beinhaltete. Die Zwischenräume der Templatpartikel wurden mit der Monomerlösung gefüllt und das Hydrogelnetzwerk per UV-Polymerisation erhalten. Die Templatpartikel wurden anschließend nasschemisch heraus gelöst, so dass eine poröse innere Struktur erhalten wurde. Die regelmäßige Anordnung der Poren und damit die opaleszenten Reflexionen wurden dabei beibehalten, so dass diese Systeme als inverse Hydorgelopale bezeichnet werden. Ein Porendurchmesser von mehreren hundert Nanometer, sowie durchgängige Verbindungskanäle zwischen den einzelnen Poren sollten eine Diffusion von großen (Bio)molekülen erleichtern, was bei bisherigen Systemen ein Problem darstellte. Die Copolymerzusammensetzung wurde dabei so gewählt, dass ein Kollaps des Hydrogels über 35 °C stattfand. Alle Hydrogele zeigten ausgeprägte Quellung in Wasser unterhalb der kritischen Temperatur. Der Einbau von reaktiven Comonomeren mit Hydroxylgruppen gewährleistete dabei die Funktionalisierbarkeit des Hydrogels mit Erkennungsgruppen für entsprechende Analytmoleküle, wie z.B. Proteine. Als Testsystem wurde Biotin als Erkennungseinheit für Avidin in das Hydrogel mittels polymeranaloger Steglich Veresterung eingebaut. Die Menge an zugänglichem Biotin wurde dabei per colorimetrischem Bindungsassay quantifiziert. Dabei zeigte sich, dass sich die Wellenlänge der Reflexion nach Zugabe von Avidin zum biotinylierten inversen Hydrogelopal signifikant verschob und damit das Bindungsereignis visuell auslesbar ist. Dieser Effekt beruht auf dem veränderten Quellungsverhalten des Hydrogels nach Bindung des hydrophilen Proteins Avidin in Wasser, welches durch den thermosresponsiven Charakter des Hydrogels verstärkt ist. Ein Aufweiten oder Schrumpfen der Poren ändert die Abstände der gleichmäßig angeordneten Poren, welche für die Farbe des inversen Opals verantwortlich sind. Auf Basis dieser Erkenntnisse lassen sich möglicherweise Sensormaterialen für die Erkennung weiterer Biomoleküle in der Größenordnung von Avidin erstellen.
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Whitehead, Debra Elayne. "Photonic band gap systems based on synthetic opals." Thesis, University of Salford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402126.
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ABBUD, JEAN DA SILVA. "BIOCAPTATION OF HG (II) BY BACTERIUM RHODOCCOCUS OPACUS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=16964@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROOs efluentes líquidos contaminados com metais pesados é uma ameaça ambiental, os íons metálicos tóxicos encontram-se dissolvidos, atingindo eventualmente o topo da cadeia alimentar e assim, tornando-se um fator de risco para a saúde humana e ambiente. Diversos métodos de tratamento de efluentes como precipitação química, coagulação, floculação, flotação, troca iônica e filtração são empregados para remoção dos metais pesados. Entretanto, estes possuem algumas desvantagens quando empregados para tratamento de grandes volumes de efluentes líquidos com baixas concentrações de metais. Neste trabalho foi avaliada a cepa bacteriana Rhodococcus opacus como um potencial biossorvente para a remoção de mercúrio de soluções aquosas através de biossorção. O valor de pH adequado para a biossorção foi em torno de 5 para o metal. Os dados correspondentes à capacidade de captação do Rhodococcus opacus em função da concentração do mercúrio foi bem ajustada ao modelo de Freundlich. A capacidade de captação máxima obtida foi de 37,9 mg.g-1 para o mercúrio, equivalente a uma remoção de 73,42 %. A cinética de biossorção para o mercúrio foi modelada pela equação de pseudo-segunda ordem. Foram avaliadas também as propriedades superficiais dos microorganismos antes e após a interação dos metais para poder determinar os possíveis mecanismos implicados na biossorção mediante medições de espectroscopia de infravermelho. Os resultados apresentados mostram que o Rhodococcus opacus apresenta características adequadas no que tange a flotação biossortiva para remoção de metais.
Heavy metals presence in wastewaters is a common environmental threat, since these toxic metal ions are dissolved, eventually reaching the top of the food chain and thus become a risk factor to human health and the environment. Mercury is considered a pollutant of high risk been regulated by USEPA (United States Environmental Protection Agency). The concern regarding pollution by mercury emerges of the problems to health caused for exposition to methyl mercury found in the aquatic water and foods in normal conditions. Several methods of effluent treatment like chemical precipitation, coagulation, flocculation, flotation, ion exchange, filtration are used to remove heavy metals. These methods have some drawbacks when used for treating large volumes of wastewater with low concentration of the metal. In this study we evaluated the bacterial strain Rhodococcus opacus as a potential biosorbent for mercury removal from aqueous solutions through biosorption. The pH value suitable for the biosorption of the metal was around 5. The data corresponding to the uptake capacity of Rhodococcus opacus depending on the concentration of mercury was well adjusted to the Freundlich model. The maximum uptake capacity was about: 37.9 mg.g-1 for mercury equivalent to a removal of 73.42%. The kinetics of mercury biosorption was representated by a equation of pseudo-second order. We also evaluated the surface characteristics of the microorganism before and after the interaction of metals in order to determine the possible mechanisms involved in biosorption by measurements of infrared spectroscopy. The results demonstrated that Rhodococcus opacus shows good performance as biosorbent for bioaccumulation of Hg (II).
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Foster, Alexander. "The heterogeneity of amine oxidase with Rhodoccus opacus." Thesis, Heriot-Watt University, 2013. http://hdl.handle.net/10399/2703.
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Four native amine oxidases have been identified from Rhodococcus opacus to reveal phenotypic plasticity and catalytic activity with respect to structurally diverse natural and synthetic amines. Altering the amine growth substrate enabled tailored and targeted oxidase upregulation, facilitating catalytic differentiation and isolation. Each enzyme was purified over 80 fold by chromatography, allowing subsequent characterisation. Two oxidases possessed a copper dependent redox co-factor with broad specificity towards monoamines. Michaelis constants (KM) ranged from 0.1 to 0.9 mM for common C1–C5 aliphatic monoamines and <0.2 mM for a range of aromatic amines. The remaining two oxidases by contrast were highly specific for aliphatic diamines, with a Michaelis constants (KM) = 60 μM for putrescine by a third copper oxidase and a (KM) = 190 μM by a flavin dependent oxidase. MALDI-TOF and genomic analysis has indicated metabolic gene clusters, multiple gene activation, and complex biodegradation pathways. With a consideration of the diamine acting oxidase, a putrescine degradation pathway is confirmed that utilises oxidases in tandem with a 4-aminobutyraldehyde dehydrogenase. The taxonomic distribution of this pathway is further examined utilising phylogenetic analysis. Oxidase regulation and integration into the nitrogen cycle is then considered, with implications in bioremediation and biocatalysis discussed.
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Dang, Phuong-Nga. "Determining the functions of transcriptional regulatory genes of the npd gene cluster encoding 2,4,6-trinitrophenol degradation in Rhodococcus opacus HL PM-1." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972630740.
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He, Zhiwei. "OPAC 2000, a new pavement design system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21354.pdf.
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Lebrun, Delphine Misao. "Photonic crystals and photocatalysis : Study of titania inverse opals." Doctoral thesis, Uppsala universitet, Fasta tillståndets fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-300408.
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Due to an increase of human activity, an increase health risk has emerged from the presence of pollutants in the environment. In the transition to renewable and sustainable life style, treatment of pollutants could support the shifting societies. A motivation behind material research for environmental applications is to maximize the efficiency of the materials to alleviate environmental pollution. In the case of titania, an increase of ultra-violet light absorption is needed to overcome its bandgap to produce reactive radicals, which is the basis for photocatalysis. It has been hypothesized that photonic crystal can enhance titania photocatalysis. They are structures made of at least two dielectrics with a high refractive index contrast, ordered in a periodic fashion. For a strong contrast, photonic band gaps emerge. The effect of the photonic band gap is to force complete reflection of the incoming light within its range and multiple internal reflections at its edges. By combining photonic and electronic band gap positions, it is possible to increase the absorption at the photonic band gap edges. In this thesis, fabrication method and structural analysis of titania and alumina/titania photonic structures were presented. A thorough optical analysis was performed at all steps of fabrication – beyond what previously has been reported. The photocatalytic activity was measured with two setups. Fourier Transform Infrared spectroscopy combined with arc lamps and bandpass filters was used to monitor the degradation of stearic acid in ambient air. A home-built setup was used to degrade methylene blue in solution with ultra-violet illumination. The results in this thesis show in general no correlation of the photocatalytic activity to the photonic band gap position, even though absorbance data displayed an increase absorption in this energy range. A more controlled environment might show the effect of the structure, as seen in some of the experiments.
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Schallier, Wouter. "Subject retrieval in OPAC's: a study of three interfaces." Departament de Biblioteconomia i Documentació de la Universitat de Barcelona, 2005. http://hdl.handle.net/10150/105277.
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In this paper we study three OPAC interfaces of K.U.Leuven University Library. All three interfaces have been on-line between 2002 and 2005. The characteristics of these OPACs (search fields, labeling of the fields, search facilities, searching vs. browsing, basic vs. advanced search) are
systematically examined. Special attention is given to subject search and display, and more specifically to Universal Decimal Classification (UDC) and Medical Subject
Headings (MeSH). This comparison is particularly interesting because the indexing and classification tools (UDC, Library of Congress Subject Headings, MeSH)
remain the same in all three OPACs. However, the way these tools are presented for subject retrieval in the respective OPACs undergoes an interesting evolution. It is demonstrated that subject search and display in library catalogs can be largely improved by investing in optimal use of existing tools. We also stress the importance
of user-oriented OPAC design.
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Brito, Elisa Maria da Silva. "A OPAS, um ator político : análise do modelo tecno-assistencial proposto pelo documento "Formulación de Políticas de Salud", OPAS, 1975." Universidade do Estado do Rio de Janeiro, 1993. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=1929.
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O presente trabalho visa analisar a metodologia de planejamento contida no documento "Formulación de Politicas de SaLud", elaborado pela OPAS em 1975. Ele procura identificar as condições de sua emergência em uma determinada conjuntura econômica e política da América Latina e em um panorama de discussão do desenvolvimentismo e do planejamento social as categorias e conceitos que constituem o texto; a proposta política veiculada pelo documento, enquanto uma metodologia de planejamento de um ator político, no caso a OPAS. 0 interesse por este tipo de estudo surge em consequência da observação do conjunto das práticas do campo do planejamento nos serviços de saúde, diferentemente orientadas de acordo com os diversos tipos de propostas que incorporam. O que se observa destas práticas é que elas estão longe de romper com a concepção biologicista e normatizadora na abordagem do processo saúde/doença, mesmo que em algumas vezes se orientem por propostas que apontam concepções diferentes. O reflexo das propostas de planejamento, enquanto práticas, na organização dos serviços, acontece, geralmente, através de normatizações sobre como desenvolver as ações de saúde, e/ou através da utilização de indicadores de produção que visam medir a produtividade e rendimento. O caráter político do
planejamento é esvaziado, entendendo-se, muitas vezes, a gestão como uma mera atividade de administrar a máquina burocrática. A seleção do documento "Formulacion" ocorre porque ele foi elaborado em uma conjuntura de crise econômico-social, na qual o planejamento na América Latina passava por um momento de inflexão, caracterizado pela crítica e revisão das propostas elaboradas nas décadas de 50 e 60, e pelo debate em torno da importância da incorporação de critérios políticos nos métodos de planificação. Na área da saúde também estava presente uma discussão sobre as técnicas de planejamento, sendo apontados alguns limites do CENDES-OPAS, que era a única proposta de planejamento em saúde existente até então. O surgimento do documento "Formulacion" considerado um marco, em função dele conter uma nova proposta metodológica que se caracteriza, segundo alguns autores, por assumir a incorporação dos aspectos políticos na técnica da planificação. A fim de desenvolver as perspectivas até aqui apontadas, este trabalho está dividido em quatro capítulos: No primeiro, é discutida a metodologia de análise que será utilizada pela investigação, sendo feita, ainda, uma revisão bibliográfica da produção na área de planejamento em saúde, que aborda especificamente a década de 70; No segundo, é realizada uma análise das condições da conjuntura econômica, social e política da América Latina, no momento do surgimento do documento "Formulacion", e resgatado - o debate existente, na época, sobre o desenvolvimentismo e o planejamento; no terceiro, é discutida a emergência do documento no contexto da OPAS, e analisado o modelo tecno-assistencial veiculado pela metodologia; Já no quarto capítulo são sistematizadas as conclusões do trabalho
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GONCALVES, PRISCILA DOS SANTOS. "BIOSORPTION OF TOLUENE IN THE PRESENCE OF RHODOCOCCUS OPACUS STRAIN." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=26296@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Neste estudo foi avaliada a capacidade de adsorção do poluente orgânico tolueno em contato com a cepa Rhodococcus opacus. O tolueno foi selecionando por fazer parte do grupo de compostos BTEX (Benzeno, Tolueno, Etilbenzeno e Xileno), que possui elevada toxicidade, causando impacto ambiental em corpos hídricos, solo e ar, além de possuir características mutagênica e carcinogênica em humanos. A determinação e quantificação do tolueno na solução aquosa foram realizadas em um cromatógrafo a gás, acoplado ao espectrômetro de massas com amostrador automático headspace. A cepa Rhodococcus opacus foi caracterizada por análise de espectrometria no infravermelho e medição de potencial zeta, sendo a última realizada antes e após o contato com o tolueno. Os modelos de isotermas lineares de Langmuir, Freundlich e Temkin foram aplicados aos dados experimentais para descrever o processo de adsorção. Tendo o modelo de Langmuir se adaptado melhor ao processo em análise. As variáveis estudadas para otimizar as condições máximas de adsorção foram: tempo de contato, variação do pH, variação da biomassa. Este estudo mostrou que a cepa bacteriana R. opacus apresentou uma boa capacidade de biossorção, principalmente para concentrações baixas, onde removeu 95,99 porcento e 85,69 porcento das respectivas concentrações de 0,6 e 0,8 mg/L de tolueno, atendendo a resolução do CONAMA 357/2005 para águas salobras de Classe I.
In this study was evaluated the adsorption capacity of the organic pollutant toluene by the Rhodococcus opacus strain. Toluene was chosen by being part of the group of BTEX compounds (benzene, toluene, ethylbenzene and xylene), which has high toxicity, causing environmental impact on water bodies, soil and air, and also are mutagenic and carcinogenic to humans. The determination and quantification of toluene in aqueous solution were performed on a gas chromatograph, coupled with a mass spectrometer with headspace autosampler. The strain Rhodococcus opacus was characterized by infrared spectrometry analysis and zeta potential measurement, the last done before and after the sorption. The isotherm linear models of Langmuir, Freundlich and Temkin were applied to the experimental data to describe the adsorption process. Having the Langmuir model better adapted to process analysed. The variables studied to optimize the maximum adsorption conditions were: contact time, pH variation, biomass variation. This study showed that the bacterial strain R. opacus has good biosorption capabilities, particularly at low concentrations, where it removed 95.99 percent and 85.69 percent of the respective concentrations of 0.6 and 0.8 mg/L of toluene, attending the CONAMA resolution 357/2005 for salt waters of Class I.
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PUELLES, JHONATAN GERARDO SOTO. "HEMATITE FLOTATION USING A CRUDE BIOSURFACTANT EXTRACTED FROM RHODOCOCCUS OPACUS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29688@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
BOLSA NOTA 10
A bioflotação é definida como um processo de separação, através do qual o mineral de interesse é flotado ou deprimido seletivamente, utilizando os reagentes de origem biológica, também conhecidos como bioreagentes. Estas substâncias são caracterizadas por possuírem uma química verde, seletividade e potencial para tratar a partículas finas. Neste sentido, o objetivo principal da pesquisa é a avaliação de um biosurfactante não refinado extraído da bactéria Rhodococcus opacus na flotação de hematita. Na primeira fase, foi desenvolvido um protocolo para a extração dos biosurfactantes intracelulares e aqueles associados a parede celular da bactéria. Mediante extração com etanol a 121 graus celsius e 2 atm, as substâncias anfifílicas foram liberadas e solubilizadas. A recuperação média de biosurfactante não refinado foi de 0,3 g por dm cubico. A caracterização por FTIR identificou grupos álcool (menos OH), cetona (C igual O) e cadeias de carbono saturadas e insaturadas. Que podem compor os mycolatas e trehalolipideos que são encontrados na parede celular da bacteria. Por estudos eletroforéticos encontrou-se umPIE de 7,5 e um PZC em torno de 7,6. Aplicando o modelo Gouy-Chapman e o modelo misto de Gouy Chapman e o capacitor de placas, foi possível estudar o efeito do biosurfactante no comportamento eletrostático das partículas de hematita. Predizendo como elas foram se tornando hidrofóbicas em valores de pH ácido e como sua flotabilidade diminuía em pH básicos, após interação com o biosurfactante. Finalmente, foi testado o biosurfactante e a própria bactéria em ensaios de microflotação de hematita, resultando o primeiro na melhora na flotabilidade de hematita. Os resultados mostraram uma boa afinidade e baixo consumo de reagente.
Bioflotation is defined as a separation process by which the mineral of interest is floated or depressed selectively, using reagents of biologic origin also known as bioreagents. These substances are characterized by their green chemistry, selectivity and potential to treat fine particles. Currently they are been studied with the expectative of substitute the synthetic reagents used in the mineral flotation processes. Between the diverse microorganisms, the hydrophobic bacteria Rhodococcus opacus has been studied as biofrother and biocollector in hematite flotation. In that sense, the research s principal objective is the assessment of the hematite floatability using a crude biosurfactant extracted from the bacteria Rhodococcus opacus and consequently determine its potential as an alternative against synthetic reagents or the bacteria itself. In a first stage, it was developed a protocol for the extraction of cell associated and intracellular biosurfactants from the bacteria. Throughout ethanol extraction at 121 degrees centigrade and 2 atm, the cell associated substances where released and solubilized. The average crude biosurfactant recovery was around 0.3 g per L of broth. Characterization by FTIR identified alcohol (minus OH) and ketone (C equal O) groups as well as saturated and unsaturated carbon chains. Which may compose the mycolates and trehalolopids that are found in the cellular wall of the genera Rhodococci. Electrophoretic studies of the hematite sample, before BS interaction, found an IEP around a pH of 7.5 and a PZC at pH 7.6. Applying the Guoy-Chapman model and the mixed model of Guoy Chapman and the plate capacitor, it was possible to study the effect of the biosurfactant onto the electrostatic behavior of the hematite particles. The model predicted the hydrophobicity of the modified hematite at acid pH. Finally it was tested the crude biosurfactant against the bacteria itself in microflotation tests, resulting the first one in an improved hematite floatability. The results showed a high affinity of the crude biosurfactant for hematite particles and relatively low reagent consumption.
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Jankūnas, Vytautas. "Odos persodinimo operacijos veiksmingumas gydant lėtines venines kojų opas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050630_213621-87507.
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Abbreviations
ADP – autodermoplastics.
CUL – chronic ulcers of legs.
CVUL – chronic venous ulcers of legs.
DGP – a doctor of general practice.
KMU – Kaunas Medicine University.
KMUH –Kaunas Medicine University Hospital.
CSVD – Clinic of Skin and Venereal diseases.
1. Introduction
The pathology of chronic ulcers of legs is quite often and it makes a huge influence on the daily life of a patient. According to the literature, ulcers open to 1,5 from 1000 people who are under the age of 65, and if we take into account healed up ulcers of legs, there are 36 people from 1000 to whom ulcers of legs have ever been opened. The reason of ulcers up to 80% of all cases is chronic insufficiency of veins. In Lithuania there are about 150 000 patients suffering from the chronic insufficiency of leg vein blood circulation, and about 30 000 of which are venous ulcers of legs. As in Lithuania in some of the medical institutions the treatment and the prophylaxis of chronic venous blood circulation and ulcers is insufficient, the above mentioned numbers of patients may be even higher.
All the authors have noted that the oftenest reason of CUL is the insufficiency of venous blood circulation. In this case, CUL open due to the increased pressure in leg veins. The main reason for that is the insufficiency of surface and deep veins and the perforating vein valves. The good functioning of mentioned veins and their valves is necessary so that the blood could come back to the heart during each... [to full text]
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Karlsson-Broström, Ingela. "”Det funkar för mig” : Användbarhetsfaktorer i ett OPAC-system." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20211.
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The object of this study is to examine the effective functionality of an OPAC-system while a few participants interacted with the catalogue. I’ve used Carl Martin Allwood’s (1998) four designed usability factors to be able to estimate the effective functionality of the online catalogue. Theoretic basis is Human Computer Interaction together with Allwood’s four defined usability factors. They are: adjustment, ease of use, user acceptance and user competence. This study is conducted with a verbal protocol method which encourages the seven participators to “think aloud” while performing tasks. The study shows that the participants interact most effective in those functions they’re accustomed with. Which indicate that the OPAC-system have a high grade of user acceptance. The end users with more experience of using Internet search engines requested similar search capabilities and settings in the online catalogue. They tend to lack a little bit of understanding to the limitations of the OPAC which therefore indicate their lack of user competence. Some task problems occurred while the participators interacted in steps and functions they weren’t familiar with. They also spoke of the difficulties with subject searching and that they would like to know the best way to make search queries. I estimate some need of more user friendly functions and services, especially in the help section. The study shows that it is essential to educate users in ways to interact with the OPAC-system in a more effective manner.
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Videke, Ola. "En undersökning av Libra IIIs OPAC utifrån två perspektiv." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20614.
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This master thesis is an attempt to study the interface in itself, where the human meets the machine and the problems that can arise. I study a particular interface, namely the OPAC of Libra III. In 1999 IFLA presented recommendations for what an OPAC shall contain, and in one part of my master thesis I compare Libra III with these recommendations from my opinion. In another part of my master thesis I make an investigation where I let five by me chosen persons answer some questions from me, both by doing and verbally. I draw the conclusion that Libra III follows most of the recommendations of IFLA in a sufficient way. There are deficiencies in how plain you can see what is happening in the system when your search for example doesn't give any hits. Really important the simplicity seems to be to make a search successful, and this IFLA recommends at the same time as my subjects of the experiment look for it. From my point of view failures depend on a combination of the fact that the constructors of the system haven't taken enough consideration to the end-users of the system and that the education of the users hasn't been good enough. Taken altogether my judgement of Libra III after all is that it is a good system both seen from IFLA and from my subjects of the experiment, but that this is a field where more can be done.Uppsatsnivå: D
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COURTEL, KARL. "Etude et developpement d'un coprocesseur de calcul matriciel : opac." Rennes 1, 1991. http://www.theses.fr/1991REN10019.
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Opac est un prototype d'operateur optimise pour le traitement d'algorithmes compute-bounds autour desquels sont frequemment articulees les bibliotheques de calcul numerique ou de traitement du signal. Opac est programmable et peut etre utilise comme unique coprocesseur numerique d'un microprocesseur. Cet operateur, qui a fait l'objet d'une realisation, est destine a seconder une unite entiere de type risc dans les calculs flottants. Opac peut approcher des performances d'une multiplication-accumulation flottante sur un grand nombre d'applications malgre la faiblesse de la bande passante effective de la memoire d'un microprocesseur. Nous montrons ainsi une solution possible pour augmenter les performances effectives des microprocesseurs et les faire approcher des performances theoriques. Opac est muni de mecanismes originaux qui permettent: 1) de gerer efficacement les boucles courtes; 2) d'utiliser un faible volume de microcode; 3) d'acceder rapidement et simplement une memoire interne geree en fifo. Dans le contexte des nouvelles habitudes de programmation, basees sur l'utilisation de bibliotheques de calcul, opac permet d'augmenter notablement les performances de nombreuses applications
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BOTERO, ANA ELISA CASAS. "BIOFLOTATION OF MAGNESITE, CALCITE AND BARITE USING RHODOCOCCUS OPACUS AS BIOREAGENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10515@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORA bactéria Rhodococcus opacus foi avaliada como biorreagente para a flotação dos minerais da magnesita calcita e barita. As análises para determinar a conformação de parede o R. opacus estabelecem que é constituída por macromoléculas com características anfipáticas. O balanço entre grupos catiônicos e aniônicos da parede atribui um ponto isoelétrico equivalente de 3,2. Os resultados dos testes de aderência indicam que a bactéria R. opacus tem uma forte afinidade por superfícies de características ácido - base. Medidas dos minerais antes e após da interação com o R. opacus revelaram que embora fossem observadas modificações sobre todas as superfícies dos minerais, a bactéria R. opacus apresentou uma melhor afinidade pela superfície da magnesita. A capacidade de adsorção das células sobre as superfícies foi fortemente dependente dos valores de pH e a velocidade de adsorção atingiu a máxima concentração de células nos primeiros 5 minutos. As isotermas para a adsorção da bactéria sobre os minerais poderiam ser categorizadas do tipo Lagmuir (L) , II. A melhor flotabilidade foi observada em pH 7. Para a magnesita, a porcentagem foi de 92% usando uma concentração de R. opacus de 100 ppm. Para calcita os melhores resultados apresentaram flotabilidade de 55% para uma concentração de 250 ppm. Em relação à barita, os melhores valores de flotabilidade (60%) foram obtidos para uma concentração de R. opacus de 350 ppm. A aproximação termodinâmica determinou que a energia de adesão era negativa para todos os sistemas, sugerindo assim uma adsorção espontânea da bactéria sobre as superfícies minerais. Para magnesita e calcita as teorias DLVO confirmam os resultados experimentais, as atrações eletrostáticas entre as partículas determinaram as forças de interação. Já para barita, a teoria de XDLVO poderia predizer o comportamento das células sobre o mineral. Neste caso as interações ácido-base seriam as responsáveis pela adesão.
Rhodococcus opacus micro-organism was evaluated as a biocollector for flotation of calcite and magnesite and barite. Analyses of R. opacus cell wall indicated the macromolecules configurationl. The IEP value of R. opacus was around 3.2,. The acidic IEP value of R. opacus could be due to the presence of anionic groups on the wall that dominate over the cationic groups. The adherence test showed the R. opacus affinity for acid-base surfaces.The behavior of the minerals, before and after R. opacus interaction, was evaluated and showed that the cells adhesion shifted both the minerals zeta potential curves and the reversal charges in comparison to their original isoelectric points. Adhesion tests suggested a higher affinity of the bacteria for magnesite than calcite and barite. The experiments of the adsorption rate of the R. opacus on the minerals surfaces showed fast behavior, achieving a maximum of cell adsorption after 5 minutes. Adsorption isotherm curves for the minerals could be categorized as Lagmuir (L) type II. The best bioflotability results for the minerals were achieved for pH 7. Magnesite reached values around 93% for a R. opacus concentration of 100 ppm. For calcite the best flotability was of 55% for a R. opacus concentration of 220 ppm. For barite, the best flotability achieved 70% for a bacterial concentration of 350 ppm. Using the thermodynamic approach of the minerals systems, the adhesion energy of R. opacus on the surfaces was negative. The result suggested a spontaneous adsorption of R. opacus on to the all minerals. For magnesite and calcite, the DLVO theory can predict the cell behavior on the minerals surfaces. The electrostatic attractions determine the interaction forces. For barite and pH 7, the X- DLVO theory predicted the R. opacus adhesion on the surface by acid base interactions.
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CAYLLAHUA, JAVIER ENRIQUE BASURCO. "BIOSORPTIVE FLOTATION OF NICKEL AND ALUMINUM USING A RHODOCOCCUS OPACUS STRAIN." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12114@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORFUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
A contaminação dos efluentes líquidos com metais pesados é uma ameaça ambiental comum, já que estes íons metálicos tóxicos encontram-se dissolvidos, atingindo eventualmente o topo da cadeia alimentar e assim se tornar um fator de risco para a saúde humana e ambiente. Diversos métodos de tratamento de efluentes como precipitação química, coagulação, floculação, flotação, troca iônica, filtração são empregadas para remoção dos metais pesados; estas possuem algumas desvantagens, quando empregados para tratamento de grandes volumes de efluentes líquidos com concentrações mínimas. Neste trabalho foi avaliada a cepa bacteriana Rhodococcus opacus como um potencial sorvente para a remoção de Ni(II) e Al(III) de soluções aquosas por flotação biossortiva, através de ensaios em batelada. O valor de pH adequado para a biossorção e flotação foi entorno de 5 para ambos metais. Os dados correspondentes à capacidade de captação do Rhodococcus opacus em função da concentração do níquel e do alumínio foram bem ajustados ao modelo de Redlich- Peterson e ao modelo de Temkin, respectivamente. As capacidades de captação máxima obtidas foram: 7,63 e 41,59 mg.g-1 para o níquel e alumínio, nesta ordem. A cinética de biossorção para o níquel e alumínio foi modelada pela equação de pseudosegunda ordem. Foram avaliadas também as propriedades superficiais do microorganismo antes e após a interação dos metais para poder determinar os possíveis mecanismos implicados na biossorção mediante medições eletrocinéticas e espectroscopia de infravermelho. Na flotação biossortiva, verificou-se que o microorganismo apresenta propriedades muito promissoras como coletor e espumante, obtendo-se porcentagens de remoção de 90% e 95% para o níquel e alumínio, respectivamente. Os resultados apresentados mostram que o Rhodococcus opacus apresenta características adequadas no que tange a flotação biossortiva para remoção de metais.
Heavy metal pollution of wastewater is a common environmental threat, since the toxic metal ions dissolved can eventually reach the top of the food chain and thus, become a risk factor for people`s health. Various methods of effluent treatment such as chemical precipitation, coagulation, flocculation, flotation, ionic exchange and filtration are commonly used for heavy metals removal from liquid streams; these techniques possess some disadvantages, particularly, inadequate metals removal when applied to dilute effluents on a large scale basis. In this work, a Rhodococcus opacus strain was evaluated as a potential biosorbent for Ni(II) and Al(III) removal from aqueous solution for biosorptive flotation process, trough experimental batch experiments. The pH value suitable for biosorption and flotation was around 5 for both metals. The data pertaining to the uptake capacity of the Rhodococcus opacus as a function of the nickel and aluminum ion concentration had been fitted to the Redlich- Peterson and Temkin isotherm model, respectively; where the maximum uptake capacities obtained were: 7,63 and 41,59 mg.g-1 for nickel and aluminum, respectively. The nickel and aluminum kinetics biosorption were modeled using a pseudo second order rate equation. The superficial properties of the microorganism had also been evaluated before and after the interaction with the metals, to be able to find out the possible mechanism implied in the biosorption; by means of the electro kinetic measurements (Zeta Potential) and Infrared spectroscopy (FTIR). In the biossorptive flotation, it was verified that the microorganism presents excellent properties a collector and foaming agent, reaching 90% and 95% removal of nickel and aluminum. The results of this work showed that the Rhodococcus opacus has a strong and feasible engineering potential for heavy metals removal by biossorptive flotation.
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Gehde, Annette. "Konzeption eines OPAC's für die wissenschaftliche Dokumentation des Europäischen Dokumentationszentrums Heidelberg." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11675639.
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Santos, Elisiane Iza dos. "Comparação de métodos pata medição de absortância solar em elementos opacos." reponame:Repositório Institucional da UFSC, 2012. https://repositorio.ufsc.br/handle/123456789/106773.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Civil, Florianópolis, 2012Made available in DSpace on 2013-12-05T22:19:13Z (GMT). No. of bitstreams: 1 320198.pdf: 9520176 bytes, checksum: 832300335d27b28ab4879f313f35bcf8 (MD5) Previous issue date: 2012
A radiação solar é um dos fatores que mais contribui para o ganho térmico em edificações, principalmente em regiões tropicais e de baixas latitudes, como é o caso do Brasil. As trocas de energia (luz e calor) entre os meios exterior e interior das edificações dependerão, fundamentalmente, da envoltória construtiva e de suas propriedades termo-físicas, em especial a propriedade de absortância para os componentes opacos. A absortância dos componentes opacos da envoltória construtiva determinam parte do impacto da radiação solar na edificação, pois indicam qual fração da energia solar que chega à edificação será absorvida por seu envelope, afetando seu ganho de calor e as temperaturas internas. A falta de dados atualizados de absortância solar para superfícies opacas faz com que pesquisadores e especialistas utilizem a percepção visual ou valores estimados de absortância, acarretando em uma escolha muitas vezes equivocada sobre a cor da envoltória, que pode causar uma cor com alta absortância e baixa eficiência energética por parte da envoltória. Neste sentido, o valor da absortância das superfícies externas do edifício deve ser o mais preciso possível e quando feita a análise da absortância desses materiais na própria edificação é de suma importância que seja usado o instrumento correto para as características da envoltória. Este trabalho apresenta uma proposta para obtenção de dados de absortância solar de superfícies opacas, verificando métodos utilizados para análise absortiva de materiais opacos, avaliando a viabilidade de cada um desses métodos em função das diferentes texturas de materiais rugosos. Para comprovar a aplicabilidade dos métodos propostos serão realizados estudos com quatro instrumentos de medição para diferentes níveis de texturas de superfícies opacas, verificando os efeitos da rugosidade sobre a absortância dessas superfícies. Os métodos baseiam-se em medições realizadas com uma bancada (com monocromador e uma esfera integradora), um espectrômetro portátil Alta II, um Luxímetro digital e um Luminancímetro. O trabalho também contribui com valores de absortâncias solares de tintas para a construção de um banco de dados referente às tintas disponíveis comercialmente no Brasil
Abstract: Solar radiation is one of many factors that contribute in gain heat of buildings, mainly in tropical regions and low latitudes, which is the case of Brazil. The changes of energy (heat and light) between outer and internal buildings depend mainly on the envelope constructive and thermo physical properties, specially the absorbance for opaque components. The absorbance of opaque components of constructive envelope determine a portion of the impact of solar radiation in the building, they indicate what fraction of solar energy that reaches the construction will be absorbed by the envelope, affecting your heat gain and internal temperatures. The lack of update data of solar absorbance for opaque surfaces makes researchers and specialists use visual perception or estimated values of absorbance, resulting in a choice often mistaken about the color of the envelope, which can cause a color with high absorbance and law energy efficiency on the part of the envelope. In this sense, the absorbance value of the building´s external surfaces has to be as accurate as possible, and when doing the absorbance analysis of these materials in the building itself it is very important that the right instrument is utilized given the characteristics of the envelope.This paper presents a proposal for obtaining data from solar absorbance of opaque surfaces, checking absorptive methods used for analysis of opaque materials, assessing the viability of each of these methods according to the different textures of rough materials. To prove the applicability of the proposed methods, studies with four measuring instruments for different levels of textures on opaque surfaces will be conducted, verifying the effects of roughness on the absorbance of these surfaces. These methods are based on measurements made by the bank (monochromator and a sphere of integration), one portable spectrometer high II, a digital Luximeter and a luminancemeter. This work also contributes with the values of solar absorbance for paints with the proposed of building a database concerning paints commercially available in Brazil.
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Gu, Jing. "The dissolution rates of amorphous silica and opal-CT." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-09052009-041033/.
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Prado, Ulisses Soares do. "Nova alternativa para reaproveitamento do resíduo perigoso gerado na produção de alumínio primário (SPL): obtenção de vidros opacos e fritas." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-09092009-183635/.
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O resíduo gerado na demolição do revestimento de cubas eletrolíticas de produção de alumínio é classificado, segundo normas internacionais e a ABNT, como resíduo perigoso devido à presença de fluoretos e cianetos. Este trabalho apresenta uma nova alternativa para eliminação desse resíduo, conhecido como spent pot lining ou simplesmente, SPL, segundo a qual os cianetos são destruídos termicamente e parte do flúor fixada em vidros entrando em sua composição. Foi realizado estudo inédito para a aplicação da fração mais carbonosa desse resíduo, que corresponde à metade do todo, como matéria-prima para obtenção de vidros opacos e fritas aplicáveis em vidrados para revestimentos cerâmicos. Para tal, foi estudado o tratamento térmico prévio do o SPL com adição de calcário, para eliminação de carbono e cianetos e minimização da volatilização dos fluoretos durante o aquecimento, tendo sido determinados os parâmetros ideais para esse tratamento. Após tratamento, o resíduo foi utilizado como parte da composição de vidros opacos tendo uma das formulações sido analisada quanto a sua composição química, resistência química e análise microestrutural. O resíduo tratado também foi utilizado na formulação de fritas usadas nos vidrados de revestimentos cerâmicos e em algumas composições obteve-se fritas similares às comerciais. Estas foram comparadas às comerciais segundo critérios específicos, com resultados bastante promissores. Os teores de fluoretos e cianetos foram analisados nas várias fases do processo de obtenção dos vidros opacos e das fritas.The solid waste from deteriorated linings of cells in the aluminum metal production is called spent pot lining or SPL. Because of the presence of leachable cyanide and fluoride compounds the SPL is classified by internationals standards and the Brazilian Association of Technical Standard (ABNT) as hazardous waste. The purpose of the present work is to evaluate the use of this carbonaceous fraction as a raw material to obtain glasses. This fraction or first cut is half of the total waste. Its a new alternative way for disposing this waste by thermally decomposing the cyanides and fixing part of the fluorides into the glass structure. This work also evaluates the use of SPL to obtain opal glasses and glass frits which could be further used as glazes in the ceramic industry. The SPL was previously heat treated and mixed to lime to eliminate carbon and to minimize the fluoride volatilization, respectively. The heat treatment conditions were optimized. The treated waste was mixed with other inorganic compounds to obtain opal glasses. The materials were analyzed to determine the final composition, corrosion resistance and microstructural characteristics. The treated SPL was also used to obtain glass frits with similar characteristics of commercial materials. These materials were compared to commercial materials considering specific criteria and the results were promising. In both cases the fluorine and cyanide contents were analyzed during the entire glass production process.
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Geueke, Birgit. "Neue Aminosäureoxidasen aus Rhodococcus opacus und Arthrobacter protophormiae: Untersuchungen zur biochemischen Charakterisierung, Klonierung und Expression." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965472159.
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Steiner, Esther Susanne. "OPAC 2.0 mit Web 2.0-Technologie zum Bibliothekskatalog der Zukunft? /." Stuttgart : Hochschule der Medien, 2007. http://opus.bsz-bw.de/hdms/volltexte/2007/624/pdf/steiner_bachelorarbeit.pdf.
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Schöllhorn, Katharina. "Benutzer am OPAC – werden sie bedient oder sind sie es?" Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-64752.
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Onlinekataloge erlauben den Nutzern den Zugang zum Bestand einer Bibliothek; Normdaten bilden darin die Grundlage für zwei wesentliche Sucheinstiege: Die Recherche nach Personen und die inhaltliche Suche mit Schlagwörtern. Benutzeranalysen zeigen erwartungsgemäß, dass dies nach den Titelstichwörtern die am häufigsten gestellten Suchanfragen sind. Es wird aber auch deutlich, dass in beiden Fällen die Wahrscheinlichkeit eines Nulltreffer-Ergebnisses, d.h. das Scheitern der Suche, sehr hoch ist. Normdaten sollen eine effektive Recherche ermöglichen – aber wie effektiv gestaltet sich diese Recherche für den Benutzer tatsächlich?
Als bibliothekarische Dienstleistung richtet sich der Onlinekatalog an den Nutzer, er sollte sich demnach an dessen Bedürfnissen und Kenntnissen orientieren. Viele Suchanfragen bei Recherchen mit Normdaten führen ins Leere, weil dem Benutzer die formalen Eingabevoraussetzungen ebenso fremd sind wie die der Erschließung zugrunde liegenden bibliothekarischen Regeln. Es zeigt sich auch, dass die Umsetzung neuer Recherchemöglichkeiten mit Normdaten alleine nicht genügt, auch die Darstellung im OPAC muss beim Vorwissen der Nutzer ansetzen. Diese erwerben ihre Recherchekompetenz vor allem bei Suchmaschinen wie Google, so dass Fachterminologie oder Unübersichtlichkeit im Onlinekatalog nur zusätzlich verwirren.
Anhand verschiedener Anwendungsbeispiele soll der Vortrag zeigen, welche Probleme sich dem Benutzer bei der Recherche mit Normdaten stellen, aber auch, wie das Potential der Normdaten in Onlinekatalogen noch besser genutzt werden kann.
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Eriksson-Åhl, Camilla. "PennTags : En kvantitativ empirisk studie av en read/write OPAC." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18530.
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The aim of this thesis is to study the phenomenon of read/write OPAC by looking at how students at Pennsylvania University use PennTags in order to influence document descriptions in the library catalogue. The main questions to be answered are to what extent PennTags is being used in different subject areas and what users contribute to document descriptions through tagging in different subject areas. Studying the posts created by a sample of PennTags users from a quantitative approach I try to find out if there is reason to believe that the activity of users and users’ possibility to make meaningful contributions are dependent of the subject matter being dealt with in documents described, as anticipated by the theory of pace layering. I find that user interest in influencing the library catalogue through PennTags appears to be low in general, with exception for in the subject areas of the main classes Language and literature and Social sciences in Library of Congress Classification. Users do however make meaningful contributions to the document descriptions through tagging in 59 % of the cases. The results support only vague evidence of the connection anticipated by the theory of pace layering and I suggest that other explanatory models must be sought in order to understand user behaviour in systems like PennTags.Uppsatsnivå: D
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Mattos, Ruben Araujo de. "A teoria da programação de saúde no método CENDES/OPAS." Universidade do Estado do Rio de Janeiro, 1989. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=6501.
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Este trabalho é uma análise de um método de Programação de saúde o método GENDES/OPAS tal como apresentado no informe Problemas Conceptuales y Metodológicos de Programación de la Salud. Discute-se a teoria da programação de saúde proposta neste documento. Envolve a discussão dos objetivos do governo que o adota e a sua organização, mas também envolve a análise da coerência dessa proposta com a teoria que a fundamenta. O primeiro capítulo apresenta as diversas acepções do termo planejamento procurando elaborar o esqueleto conceitual com o qual analisou-se o método CENDES/OPAS. No segundo capítulo, analisou-se o contexto teórico do método CENDES/OPAS, o debate sobre desenvolvimento e sua relação com a saúde. Analisou-se também a Carta de Punta del Este, comparando-se com a definição de programação de saúde adotada pelo documento do CENDES/OPAS. No terceiro capítulo, discutiu-se a incorporação dos conceitos econômicos e dos princípios gerais da programação pelo método CENDES/OPAS. O quarto capítulo é dedicado a descrição e ao exame do processo de elaboração dos planos nacionais de saúde tal como proposto naquele documento. No quinto capítulo, fizeram-se algumas considerações críticas ao método. No sexto capítulo procurou-se, a título de síntese, sistematizar as conclusões deste trabalho.This work is an analysis of a method of programming of health - GENDES / PAHO method as presented in the report " Problemas Conceptuales y Metodológicos de Programación de la Salud" . It discusses the theory of health programming proposed in this document. Involves discussion of the objectives that the government and organization adopt, but also involves the analysis of the proposal consistency with the theory underlying it . The first chapter ntroduces the various meanings of the term conceptual planning elaborate looking skeleton with which analyzed the CENDES / PAHO method. In the second chapter , we analyzed the theoretical context of CENDES / PAHO method, the debate on development and its relationship to health . Also analyzed the Charter of Punta del Este , comparing with the definition of health programming adopted by the CENDES / PAHO document. The third chapter discussed the incorporation of economic concepts and general principles of programming by CENDES / PAHO method. The fourth chapter is devoted to the description and examination of the process of national health plans process as proposed in that document . In the fifth chapter , there have been some critical considerations to the method . In the sixth chapter we tried to , by way of summary, the findings of this systematic work.
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MORAN, JOSE JONATHAN VALLEJOS. "FUNDAMENTAL ASPECTS OF THE ADHESION OF RHODOCOCCUS OPACUS STRAIN ONTO APATITE SURFACE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2012. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=21077@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORPROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
A bactéria Rhodococcus opacus apresenta a capacidade de tornar hidrofóbica a superfície do mineral de apatita, devido aos compostos presentes na sua parede celular. Para avaliar esta característica da bactéria, foi estudada no presente trabalho a influencia de diferentes parâmetros para tentar entender a interação entre bactéria e o mineral. Os resultados de mobilidade eletroforética da bactéria e mineral mostram um ponto isoelétrico em torno a 2,8 e de 2,5 respectivamente. Após a interação da bactéria com o mineral pode se observar uma variação na curva de potencial zeta do mineral. Os resultados mostram que existe uma maior afinidade da parede celular da bactéria pela superfície mineral de apatita em um pH igual à 7. Foi observado que um aumento na concentração inicial de bactéria é favorável para a captação (mg bactéria/g mineral). Os dados experimentais de adesão foram ajustados aos modelos de Langmuir e Freundlich, apresentando o ultimo um melhor ajuste. As constantes de Freundlich obtidas foram 1.111, 1.154, 1.198 para 293 K, 303 K, 313 K respectivamente. Os resultados mostram uma influencia positiva na captação quando existe um incremento na temperatura e no tempo de interação. Foi avaliado o modelo cinético de pseudo-primeira ordem obtendo-se constantes de taxa de 0.0228, 0.0353, 0.449 min-1 para 293 K, 303 K, 313 K respectivamente. Os resultados mostram uma energia de ativação de 25,91 KJ/mol, sugerindo-se a predominância de interações químicas entre a parede celular da bactéria e a superfície mineral. As imagens do microscópio eletrônico de varredura evidenciaram a adesão em multicamadas da bactéria sobre o mineral de apatita. O presente trabalho provê um pouco de conhecimento para o uso potencial da bactéria como biorreagente na flotação.
Bacteria Rhodococcus opacus has the ability of turn hydrophobic the surface of apatite mineral due compounds present in their cell wall, then for evaluate this particular characteristic of the bacteria, was studied the influence of different parameters to try to understand the interaction between bacteria and mineral. The results of electrophoretic mobility of the bacteria and mineral showed an isoelectric point around 2.8 and 2.5 respectively; after of the bacteria and mineral interaction was observed a change in the zeta potential curve of the apatite mineral. The results showed that there is a greater affinity between the bacterial cell wall and the surface of apatite mineral at pH around 7. It was observed that an increasing in the initial concentration of bacteria is favorable to uptake (mg bacteria/ g mineral). The experimental data of adhesion were fitted of the Langmuir and Freundlich models. Freundlich model showed a suitable adjustment and was obtained constants n equal 1.111, 1.154, 1.198 to 293 K, 303 K, 313 K respectively. The results showed the positive influence in the uptake when there is an increase of temperature and interaction time. Was evaluated the pseudo-first order kinetic model and were obtained rate constants of 0.0228, 0.0353, 0.449 min-1 to 293 K, 303 K, 313 K respectively. The results showed an activation energy of 25.91 kJ / mol, suggesting the predominance of chemical interactions between the bacterial cell wall and mineral surface. The images of scanning electron microscope revealed the multilayer adhesion of bacteria onto apatite mineral. This study provides some understanding for the potential use of bacterial as bioreagent in flotation.
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Miranda, Sueli de Melo. "A comunhão do opaco:: arte, poesia e transmissão em Amilcar de Castro." Universidade Federal de Minas Gerais, 2008. http://hdl.handle.net/1843/ECAP-7MCH5P.
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A tese A comunhão do opaco: arte, poesia e transmissão em Amilcar de Castro investiga a arte e o ensino do escultor Amilcar de Castro a partir da forma do silêncio, nome que o escultor dá a sua escultura, e de seus textos poéticos, no litoral entre os campos do significante e o real insondável da substância-ferro e do artista, investigação esta apoiada nos três movimentos básicos de sua arte: corte, dobra e deslocamento.
No encontro do finito com o infinito, o princípio econômico deixou sua marca para cortar sentido, dobrar em exuberância, e testemunhar que o lápis duro sem rascunho e marcado pela singularidade da rasura converteu-se em poética. Para ensinar, Amilcar escreve poemas e permite que a poesia transmita ao aluno a possibilidade da própria invenção. A presente pesquisa deixa-se levar pela poética do artista, para emprestar consequências à comparação com a psicanálise através do ensino do psicanalista Jacques-Alain Miller e de Jacques Lacan, uma vez que também a transmissão da psicanálise se faz através da poética
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Newberry, Tundi Lee. "Weathering geochemistry and geochronology of the Australian sedimentary-hosted opal deposits /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18612.pdf.
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