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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Dietary fish and haemostasis indications of anti-thrombotic properties /

Thorngren, Margareta. January 1983 (has links)
Thesis (Ph. D.)--University of Lund, 1983. / Includes bibliographical references.
42

Modeling of radiative transfer through a spherical planetary atmosphere application to atmospheric trace gases retrieval from occultation- and limb-measurements in UV-Vis-NIR /

Rozanov, Alexei. Unknown Date (has links) (PDF)
University, Diss., 2001--Bremen.
43

Atmospheric parameter retrieval from UV-vis-NIR limb scattering measurements

Kaiser, Johannes W. Unknown Date (has links) (PDF)
University, Diss., 2001--Bremen.
44

Polarisationsabhängige optische Eigenschaften und die photoschaltbare Doppelbrechung zeolithischer Wirt-Gast-Kompositkristalle

Hoffmann, Kathrin. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2002--Berlin.
45

Bildgebende Spektroskopie an Pflanzenblättern

Smolyar, Nadiya. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2003--Heidelberg.
46

High temperature UV-vis-NIR spectroscopy of glasses doped with polyvalent elements

Kido, Ladislav. Unknown Date (has links) (PDF)
University, Diss., 2005--Jena.
47

The role of epistemic communities in the formulation of foreign economic policy in Latin America: a literature review / El papel de las comunidades de conocimiento en la formación de la política económica exterior en Latinoamérica: Una revisión de literatura

Jiménez Peña, Gabriel 25 September 2017 (has links)
This paper is organized as follows. The introduction determines what Foreign Economic Policy is. Then, it builds a theoretical framework about Foreign Economic Policy formulation in developing countries, with a focus in Lain America. This discusses three different approaches: system-centered, society-centered and state-centered. Then, it explores literature about epistemic communities in Latin America in order to determine to what extent this has focus on Foreign Economic Policy formulation. Finally, it explores the importance of studying the role of epistemic communities in public agencies in charge of foreign economic relations in the region. / Este escrito está organizado de la siguiente manera. En la introducción se discutirá en quéconsiste la política económica exterior (en adelante PEE). Luego, en primer lugar, se construye un marco teórico en torno de la formación de la PEE en los países en vías de desarrollo y, en particular, en América Latina. Ello a través de tres enfoques diferentes: centrado en el sistema, en la sociedad y en el Estado. En segundo lugar, se busca mostrar de qué manera este marco teórico podría informarse del constructivismo. Asimismo, se aborda la literatura sobre las comunidades de conocimiento latinoamericanas para determinar hasta qué punto ha sido tratada la formación de PEE. Finalmente, se arriba a una conclusión sobre la necesidad de explicar el papel de las comunidades de conocimiento en los organismos o agencias públicas encargadas de las relacioneseconómicas exteriores latinoamericanas.
48

Propriedades estruturais de géis obtidos a partir de sono-hidrólise de TEOS e troca de fase líquida por acetona

Maceti, Huemerson [UNESP] 18 December 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-12-18Bitstream added on 2014-06-13T19:12:22Z : No. of bitstreams: 1 maceti_h_me_rcla.pdf: 484546 bytes, checksum: 6d093c2c96c1a1dba6ae5a651183c6b5 (MD5) / Sonogéis de sílica foram preparados a partir da sonohidrólise de tetraetilortosilicato (TEOS) e, após o envelhecimento, a fase líquida do gel foi trocada por acetona, durante a fase saturada do processo. A evolução estrutural durante a secagem do sonogel úmido com a fase líquida trocada por acetona foi estudada por espalhamento de raio-x a baixo ângulo (SAXS). A evolução estrutural do xerogel derivado do sonogel com fase líquida trocada por acetona, foi estudada em função da temperatura, por meio de espectroscopia de absorção UV-visível, medidas de densidade real e aparente, medidas de contração linear, e análises térmicas (DTA, TG e DL). Os períodos associados à evolução estrutural determinados por SAXS estão de acordo com os períodos clássicos determinados a partir das características da taxa de evaporação da fase líquida, na obtenção de xerogéis. O gel úmido pode ser descrito como formado por partículas primárias (microclusters), com densidade de cerca de 1,8 g/cm3, tamanho característico a ~ 0,67 nm e superfície fractal, que se juntam para formar uma estrutura fractal de massa, com dimensão fractal de massa D ~ 2,2 e comprimento característico ? ~ 6,7 nm. À medida que a rede colapsa durante o período de taxa de evaporação constante, no qual o gel se mantém saturado com a frente de evaporação na superfície externa do gel, a estrutura fractal de massa vai se compactando, aumentando D e diminuindo ?, com alisamento da superfície fractal dos microclusters. O xerogel obtido ao término do processo de secagem apresenta características de um sistema com poros vazios e partículas não fractais, com superfície de interface lisa e área de superfície de cerca de 385 m2/g. Os resultados das medidas de densidade aparente, de DTA e TG, mostram que os géis perdem resíduos... . / Silica sonogels were prepared from the sonohydrolysis of tetraetilortosilicate (TEOS) and the liquid phase of the gel was exchanged by acetone during the saturated stage of the process. The structural evolution of the drying of the wet exchanged sonogel was studied by small-angle x-ray scattering (SAXS). The structural evolution of the xerogel derived from the exchanged sonogel was studied as a function of the temperature by means of UV-visible absorption spectroscopy, bulk and skeletal density measurements, linear contraction measurements, and thermal analysis (DTA, TG and DL). The periods associated to the structural evolution as determined by SAXS are in agreement with those classical ones as determined from the features of the evaporation rate of the liquid phase in the obtaining of xerogels. The wet gel can be described as formed by primary particles (or microclusters) with density of about 1.8 g/cm3, characteristic length a ~ 0.76 nm e surface fractal, linking together to form mass fractal structures with mass fractal dimension D ~ 2.2 in a length scale ? ~ 6.7 nm. As the network collapses, while the liquid/vapor meniscus is kept at the external evaporation surface of the gel, the mass fractal structure becomes more compacted by increasing D and decreasing ?, with smoothing of the fractal surface of the microclusters. The xerogel obtained at the end of the drying process presents characteristics of a system with empty pores and non-fractal particles, with smooth interface surface and surface area of about 385 m2/g. The results of bulk density measurements and of DTA and TG thermal analysis show that the gels lose organic residuals and more strongly bonded water at temperatures up to 200-250 oC. This event is related with the increase of the absorption in the UV region, which was found at temperatures up... (Complete abstract, click electronic address below).
49

Interpretations of Data in Ethical vs. Unethical Data Visualizations

January 2017 (has links)
abstract: This paper presents the results of an empirical analysis of deceptive data visualizations paired with explanatory text. Data visualizations are used to communicate information about important social issues to large audiences and are found in the news, social media, and the Internet (Kirk, 2012). Modern technology and software allow people and organizations to easily produce and publish data visualizations, contributing to data visualizations becoming more prevalent as a means of communicating important information (Sue & Griffin, 2016). Ethical transgressions in data visualizations are the intentional or unintentional use of deceptive techniques with the potential of altering the audience’s understanding of the information being presented (Pandey et al., 2015). While many have discussed the importance of ethics in data visualization, scientists have only recently started to look at how deceptive data visualizations affect the reader. This study was administered as an on-line user survey and was designed to test the deceptive potential of data visualizations when they are accompanied by a paragraph of text. The study consisted of a demographic questionnaire, chart familiarity assessment, and data visualization survey. A total of 256 participants completed the survey and were evenly distributed between a control (non-deceptive) survey or a test (deceptive) survey in which participant were asked to observe a paragraph of text and data visualization paired together. Participants then answered a question relevant to the observed information to measure how they perceived the information to be. The individual differences between demographic groups and their responses were analyzed to understand how these groups reacted to deceptive data visualizations compared to the control group. The results of the study confirmed that deceptive techniques in data visualizations caused participants to misinterpret the information in the deceptive data visualizations even when they were accompanied by a paragraph of explanatory text. Furthermore, certain demographics and comfort levels with chart types were more susceptible to certain types of deceptive techniques. These results highlight the importance of education and practice in the area of data visualizations to ensure deceptive practices are not utilized and to avoid potential misinformation, especially when information can be called into question. / Dissertation/Thesis / Masters Thesis Technical Communication 2017
50

Blendas de PVC/PCL foto/termo e biotratadas com fungos de solo (Phanerochaete chrysosporium e Aspergillus fumigatus)

Campos, Adriana de [UNESP] 26 April 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-04-26Bitstream added on 2014-06-13T18:56:11Z : No. of bitstreams: 1 campos_a_me_rcla.pdf: 4152569 bytes, checksum: 41a529d2c0be5a0a79eb44e0ec1448ea (MD5) / Os plasticos constituem um dos materiais mais utilizados em nosso cotidiano. Assim, os residuos plasticos tem aumentado bastante e hoje representam 20% do total do volume de residuos, em lixoes municipais. O PVC (policloreto de vinila) e um polimero sintetico, instavel em relacao ao calor e luz, que degrada a temperatura relativamente baixa (aproximadamente 130oC), e libera HCl. A desidrocloracao gera novas especies na cadeia polimerica, ou seja, sequencias de polienos que podem ser verificadas atraves da espectroscopia de absorcao na faixa do UV-Visivel. A reciclagem do PVC apresenta algumas dificuldades intrinsecas ao comportamento do polimero, durante o processo tecnologico e, alem disso, sua biodegradacao e dificil. O PCL (poli α-caprolactona), um poliester sintetico, e sensivel a acao de enzimas microbianas, e pode sofrer hidrolise e degradacao. A mistura desses polimeros, isto e, a blenda de PVC e PCL pode constituir um meio para facilitar o ataque microbiano ao PVC, alem de melhorar ou manter as propriedades mecanicas da blenda. Processos termo e fotodegradativos podem facilitar o ataque microbiano a matriz polimerica do PVC. O presente trabalho pretende investigar a termo, foto e biotransformacao de filmes de blendas de PVC/PCL 1:1 e 3:1 com fungos de solo (Phanerochaete chrysosporium e Aspergillus fumigatus). As mudancas estruturais foram analisadas atraves da espectroscopia de absorcao no infravermelho (FTIR) e no UV-Visivel e as mudancas morfologicas, atraves de Microscopia Eletronica de Varredura (MEV) / The plastics are one of used the most materials daily. Thus, the plastics wastes have increased considerably and today represent 20% of the waste total volume in the municipal landfills. PVC (poly vinyl chloride) is a synthetic polymer, unstable in the presence of heat and light, that degrades on relative low temperature (approximately 130ºC), and releases HCl. The dehydrochlorination produces new species on polymeric chain, thus, polyenes sequences, that can be checked by the UV-Visible absorption spectroscopy. The recycling of PVC presents some difficulties due its behaviour during the technological processing and its biodegradation is difficult. PCL (polycaprolactone), a synthetic polyester is susceptible to enzymes action, and undergo hydrolysis and degradation. The blend of PVC and PCL can be one way to facilitate the microorganisms attack to the PVC polymer and to improve the mechanical properties of the blend. Thermal and photodegradation process can to facilite the microorganisms attack on PVC polymeric chain. The present work intends to investigate the thermal, photo and biotransformation of polymer films and blends of PVC/PCL 1:1 and 3:1 blends, with soil fungi (Phanerochaete chrysosporium and Aspergillus fumigatus). The structural changes were analysed by infrared absorption spectroscopy (FTIR) and the UV-Visible. The morphologics changes were investigated by scanning electron microscopy (SEM)

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