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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.
131

Actual and ideal role of vocational educators in increasing the employment rate of Puerto Ricans /

Perez Gomez, Jose M. January 1980 (has links)
No description available.
132

GRINGA-RICAN

Ruiz-Robles, Ashley M 01 January 2024 (has links) (PDF)
Gringa-Rican is a collection of short stories told through the lens of various female, Puerto Rican protagonists. They highlight the duality of one’s existence, when one is from neither here nor there. The stories explore ideas of dislocation, assimilation and identity, through a Puerto Rican family that moves from their home island to the United States. I was inspired to write these stories because of my own family’s pursuit of the American Dream. This thesis is, in part, a labor of love. Growing up, there were not many stories with families like mine. For this reason, when I decided I wanted to be a writer, I found myself trying to depict someone I wasn’t. I did not feel like I could truly write about my experience in the diaspora, because it did not matter. Eventually, this changed when I read books like We the Animals by Justin Torres, When I Was Puerto Rican by Esmeralda Santiago, and The House on Mango Street by Sandra Cisneros. For the first time, I saw myself as someone with a story worthy of being written and read. This collection is the product of years of writing, drafting and editing. I have laughed and cried, worried and dreamed. Now, I send it off to the world hoping that my work inspires others. I hope that these stories serve as both mirrors and windows. I hope that these characters, these lives I’ve created, feel as real to the reader as they do to me.
133

Revolving Scenarios

Rosales, Jorge Enrique 14 June 2010 (has links)
Revolving Scenarios is an arts-performing center located in San Juan, Puerto Rico, intended to hold different cultural / theatrical and social events. The project is presented as a sequence of acts or events that directs the observer through its different spaces. Revolving scenarios becomes a performing piece which tries to recreate a monumental and dramatic architectural spectacle in itself. It is a play performing in the landscape where the visitors / spectators become the leading actor. Due to the nature of the building's geometry and location (inspired by the site's curvilinear lines and the nautilus shell), the project continuously provides multiple opportunities for scenic tropes from the indoor / outdoors. Therefore, views revolve around the landscape, different theatre halls which continuously change and revolve around the theatrical spectacles. As humans, we constantly move and live among scenarios that continuously change, evolve and revolve around ordinary life. The performing arts center becomes a microcosm of the macrocosmic everyday performances occurring in Puerto Rico. The performing piece allows us to expand our vision, vision of the worldâ ¦our worldviews. The thesis allowed discovering poetic architectural views revolving around the theatre, the arts and culture which are constantly changing and evolving along time. / Master of Architecture
134

Estudo do comportamento térmico de asfaltenos de um petróleo brasileiro / Study of the thermal behavior of brazilian petroleum asphaltenes

Gonçalves, Maria Luisa Aleixo 27 February 2002 (has links)
A decomposição térmica dos asfaltenos é a principal responsável pela formação de coque no processamento de petróleos. O fenômeno não é claramente entendido, pelas dificuldades ainda existentes na caracterização de tais componentes pesados do óleo. Este trabalho apresenta informações sobre os produtos da decomposição térmica dos asfaltenos isolados de um petróleo da Bacia de Campos, maior bacia produtora de petróleo no Brasil. A abordagem envolveu: 1) estudos da decomposição térmica dos asfaltenos por termogravimetria (TG) em condições controladas; 2) caracterização dos produtos voláteis dessa decomposição por termogravimetria acoplada à cromatografia gasosa e espectrometria de massas (TG/DTA-CG-EM) e 3) caracterização dos produtos sólidos obtidos em diferentes temperaturas pela reação de oxidação catalisada pelo íon rutênio (RICO) que converte seletivamente alquil aromáticos em ácidos alcanóicos. A decomposição térmica dos asfaltenos foi estudada por termogravimetria. Os asfaltenos se decompõem drasticamente entre 320 e 650ºC produzindo 54% de produtos voláteis e 46% de coque. O material volátil liberado dos asfaltenos a 700°C foi analisado por TG/DTA acoplado a CG-EM. Foi identificada uma série de alcanos contendo de C3 a C10. Esse resultado causou grande surpresa, pois na análise da pirólise de diferentes asfaltenos são observados alcanos com maior número de átomos de carbono. Outro experimento foi realizado, agora em duas etapas: coleta do material volátil e injeção desta no sistema GC-EM. Desta vez foi possível identificar a série homóloga de alcanos de C11 até C33. Para o maior conhecimento da decomposição térmica dos asfaltenos, foram obtidos, em escala preparativa, produtos sólidos de decomposição térmica destes nas temperaturas de 320, 380, 400, 440, 480, 550 e 580°C. As análises realizadas nesses produtos - elementar, espectroscopia na região do infravermelho, ressonância magnética nuclear de carbono 13 no estado sólido - indicaram que quanto maior a temperatura de obtenção dos produtos sólidos, menor é o conteúdo de hidrogênio e carbono alifático. Os asfaltenos e os seus produtos de pirólise foram submetidos a reação de oxidação seletiva. Os ácidos gerados foram metilados para análise por CG-EM. Nos asfaltenos e nos produtos obtidos a 320, 380, 400 e 440°C foram identificados ésteres metílicos lineares que indicaram a presença de hidrocarbonetos alifáticos contendo de 5 a 25 átomos de carbono, ésteres metílicos de ácidos dicarboxílicos que indicaram a presença de pontes alquilicas entre os grupamentos aromáticos contendo de 3 a 15 átomos de carbono e alguns ésteres metílicos de ácidos benzenodicarboxílicos. Comparando-se o teor total desses ésteres metílicos presentes em cada produto de reação, foi verificado que a concentração dos ésteres metílicos lineares diminui lentamente a 320, 380, 400ºC, e drasticamente a partir de 400ºC. O mesmo ocorrendo com os ésteres dos ácidos dicarboxílicos e benzeno dicarboxílicos, em menor concentração que os ésteres metílicos lineares. / The thermal decomposition of asphaltenes is mainly responsible for the formation of coke in petroleum processing. The phenomena involved are not clearly understood, due to the difficulties in characterizing such heavy components. This research reports the application of thermal analysis techniques to study the thermal behavior of asphaltenes from Brazilian oil (Campos Basin). The approach involves: 1) studies of the thermal decomposition of asphaltenes under controlled conditions by thermogravimetry (TG); 2) characterization of volatile fractions by thermogravimetry and differential thermal analysis coupled with gas chromatography and mass spectrometry (TG/DT-GC-MS); 3) solid products from the thermal decomposition of asfaltenes where subjected to ruthenium (VIII) ion catalyzed oxidation reaction (RICO) that converts selectively and efficiently, alkyl aromatics to alkanoic acids. Thermogravimetry was used to study the asphaltenes thermal decomposition. The asphaltenes drastically decomposes from 320 to 650ºC to produce 54% of volatile products and 46% of coke. The volatile products of the asphaltenes at 700ºC were done by TG/DTA coupled to GC-MS. The volatile material was identified as a series of straight chain of normal alkyl ranging from C3 to C10. This result indicated limitations of the apparatus employed n-alkyl chains longer than these were expected. However, it worked well for lighter components. Another experiment, in which gaseous products from pyrolysis procedure were recovered by bubbling in CH2Cl2, accounted for the heavier components. The solution obtained this time can be analyzed by syringe injection in a CG-MS. The majority of the volatile material is constituted of straight chain alkanes ranging from C13 to C33. Knowing more about the thermal decomposition conversion of asphaltenes, the solid pyrolysis products of them were obtained in larger quantities at 320, 380, 400, 440, 480, 550 e 580ºC. They were characterized by elemental analysis and solid state 13C nuclear magnetic resonance. It was observed that at higher pyrolysis temperatures, lower the hydrogen and aliphatic carbon contents were obtained for the solid products. So, to improve knowledge on these systems, asphaltenes and their solid products from thermal decomposition were oxidized with ruthenium (VIII) ion. The acids formed were mixed with excess of ethereal diazomethane and submitted to GC-MS in order to identify the correspondent methyl esters. It was observed three homologous series: methyl esters of linear carboxylic acids ranging from C6 to C27, corresponding to chain alkyl length from C5 to C26 substituent on aromatic carbon; small amounts of dimethyl esters were also present in a homologous series, ranging from C5 to C17 indicating bridge polymethylenes between aromatics from C3 to C15 and benzene dicarboxilic acids from C10 to C12. The total content of methyl ester of each reaction products was compared. It was observed that the linear esters content decreased slowly at a 320, 380, 400°C and drastically up to 400ºC. The same occurred with the dimethyl aliphatic esters and dimethyl benzyl esters.
135

Valoración de la regeneración ósea en un modelo animal: Utilización del plasma rico en plaquetas en la curación de los defectos óseos. Estudio preliminar para un diseño experimental en conejos.

Bonete Lluch, Daniel José 03 May 2007 (has links)
INTRODUCCIÓN: Los factores de crecimiento y otras moléculas con capacidad osteoinductora pueden considerarse biomateriales que poseen actividad importante en los procesos de reparación y regeneración de los seres vivos. Esta capacidad puede utilizarse para favorecer, asegurar y aumentar lo procesos de reparación del tejido óseo. En esta tesis doctoral se realiza el estudio de la aplicación aislada en un defecto óseo, de un compuesto rico en plaquetas y factores de crecimiento, el plasma rico en plaquetas (PRP).MATERIAL Y MÉTODO: Hemos realizado un estudio experimental prospectivo, comparativo bilateral y controlado, interviniendo quirúrgicamente 30 conejos raza Nueva Zelanda, a los que se practicó defectos cavitarios de 6mm de diámetro en la metáfisis proximal de tibia y defecto un diafisarios de 6mm en el peroné. Los animales fueron divididos en 2 grupos de 15 individuos que recibieron como ttº plasma rico en plaquetas (PRP) o plasma pobre en plaquetas (ppp) en sus tibias y peroné derechos. La tibia y peroné izquierdo se utilizó como grupo control sin recibir ningún tipo de tratamiento. Los resultados se obtuvieron por medio de estudios radiológicos, TAC e histológico a las 8, 12 y 16 semanas.RESULTADOS: El estudio de las imágenes de reconstrucción de TAC, densidad mineral ósea y el análisis cualitativo de la histología reveló una mejoría del grupo tratado con plasma pobre en plaquetas (ppp) sin ser las diferencias estadísticamente significativas. Los procesos de reparación se realizaron fundamentalmente por una osificación membranosa sin observarse focos de osificación endocondral. El estudio estadístico de las diferentes variables en función del tiempo de evolución y tipo de tratamiento empleado no presentó ninguna diferencia significativa. (P < 0.05).CONCLUSIÓN: El plasma rico en plaquetas, sustancia o compuesto autólogo, seguro y fácil de obtener, en nuestro modelo experimental de defectos óseos en el animal de experimentación no se comporta como un sustitutivo óseos con capacidad osteoinductora ni osteopromotora. / INTRODUCTION: Growth factors and others molecules with osteoinductive capacity could be considered biomaterials with an important role in the biological prossess of healing in the human body. These properties could be potentially employed to enhance bone healing. Platelet rich plasma and growth factors alone were studied in an experimental bone defect model in this PhD Thesis.MATERIAL AND METHOD: A prospective, comparative bilateral and controlled experimental study was performed. A bone cavitary defect of diameter 6 mm. in the proximal tibial methaphyses and a 6 mm diaphysal fibula defect was made on 30 New Zealand white rabbits. The animals were divided in two groups of 15 rabbits that received, as treatment of the defect, platelet rich plasma (PRP) or platelet poor plasma (ppp) in the right tibia and fibula. The left tibia and fibula were untreated as a control group. The results were evaluated with a radiological, CTScan and histological studies at 8, 12 and 16 weeks.RESULTS: The 3D images from CTscan reconstruction, bone mineral density (BMD) and cualitative histological studies demonstrated an improvement in the platelet poor plasma group (ppp) without statistically significant differences. The bone regeneration was obtained from a membranous process without encondral reaction. The statistical study of different variables in relation to time and type of treatment revealed no significant differences (P < 0.05).CONCLUSION: Platelet rich plasma, easy to obtain, safe and autologous compound does not work as bone substitute with an osteoinduction capability in our bone defect experimental animal model.
136

Más cal que arena contra el posmodernismo en Mañana en la batalla piensa en mi (1994) de Javier Marias y El otoño aleman (2006) de Eugenia Rico

Tokarski, Przemyslaw. January 2010 (has links)
Title from first page of PDF document. Includes bibliographical references (p. 58).
137

The introduction of American law in the Philippines and Puerto Rico, 1898-1905

Thompson, Winfred Lee, January 1989 (has links)
Thesis (Ph. D.)--University of Chicago, 1987. / Includes index. Bibliography: p. [251]-258.
138

Estudo do comportamento térmico de asfaltenos de um petróleo brasileiro / Study of the thermal behavior of brazilian petroleum asphaltenes

Maria Luisa Aleixo Gonçalves 27 February 2002 (has links)
A decomposição térmica dos asfaltenos é a principal responsável pela formação de coque no processamento de petróleos. O fenômeno não é claramente entendido, pelas dificuldades ainda existentes na caracterização de tais componentes pesados do óleo. Este trabalho apresenta informações sobre os produtos da decomposição térmica dos asfaltenos isolados de um petróleo da Bacia de Campos, maior bacia produtora de petróleo no Brasil. A abordagem envolveu: 1) estudos da decomposição térmica dos asfaltenos por termogravimetria (TG) em condições controladas; 2) caracterização dos produtos voláteis dessa decomposição por termogravimetria acoplada à cromatografia gasosa e espectrometria de massas (TG/DTA-CG-EM) e 3) caracterização dos produtos sólidos obtidos em diferentes temperaturas pela reação de oxidação catalisada pelo íon rutênio (RICO) que converte seletivamente alquil aromáticos em ácidos alcanóicos. A decomposição térmica dos asfaltenos foi estudada por termogravimetria. Os asfaltenos se decompõem drasticamente entre 320 e 650ºC produzindo 54% de produtos voláteis e 46% de coque. O material volátil liberado dos asfaltenos a 700°C foi analisado por TG/DTA acoplado a CG-EM. Foi identificada uma série de alcanos contendo de C3 a C10. Esse resultado causou grande surpresa, pois na análise da pirólise de diferentes asfaltenos são observados alcanos com maior número de átomos de carbono. Outro experimento foi realizado, agora em duas etapas: coleta do material volátil e injeção desta no sistema GC-EM. Desta vez foi possível identificar a série homóloga de alcanos de C11 até C33. Para o maior conhecimento da decomposição térmica dos asfaltenos, foram obtidos, em escala preparativa, produtos sólidos de decomposição térmica destes nas temperaturas de 320, 380, 400, 440, 480, 550 e 580°C. As análises realizadas nesses produtos - elementar, espectroscopia na região do infravermelho, ressonância magnética nuclear de carbono 13 no estado sólido - indicaram que quanto maior a temperatura de obtenção dos produtos sólidos, menor é o conteúdo de hidrogênio e carbono alifático. Os asfaltenos e os seus produtos de pirólise foram submetidos a reação de oxidação seletiva. Os ácidos gerados foram metilados para análise por CG-EM. Nos asfaltenos e nos produtos obtidos a 320, 380, 400 e 440°C foram identificados ésteres metílicos lineares que indicaram a presença de hidrocarbonetos alifáticos contendo de 5 a 25 átomos de carbono, ésteres metílicos de ácidos dicarboxílicos que indicaram a presença de pontes alquilicas entre os grupamentos aromáticos contendo de 3 a 15 átomos de carbono e alguns ésteres metílicos de ácidos benzenodicarboxílicos. Comparando-se o teor total desses ésteres metílicos presentes em cada produto de reação, foi verificado que a concentração dos ésteres metílicos lineares diminui lentamente a 320, 380, 400ºC, e drasticamente a partir de 400ºC. O mesmo ocorrendo com os ésteres dos ácidos dicarboxílicos e benzeno dicarboxílicos, em menor concentração que os ésteres metílicos lineares. / The thermal decomposition of asphaltenes is mainly responsible for the formation of coke in petroleum processing. The phenomena involved are not clearly understood, due to the difficulties in characterizing such heavy components. This research reports the application of thermal analysis techniques to study the thermal behavior of asphaltenes from Brazilian oil (Campos Basin). The approach involves: 1) studies of the thermal decomposition of asphaltenes under controlled conditions by thermogravimetry (TG); 2) characterization of volatile fractions by thermogravimetry and differential thermal analysis coupled with gas chromatography and mass spectrometry (TG/DT-GC-MS); 3) solid products from the thermal decomposition of asfaltenes where subjected to ruthenium (VIII) ion catalyzed oxidation reaction (RICO) that converts selectively and efficiently, alkyl aromatics to alkanoic acids. Thermogravimetry was used to study the asphaltenes thermal decomposition. The asphaltenes drastically decomposes from 320 to 650ºC to produce 54% of volatile products and 46% of coke. The volatile products of the asphaltenes at 700ºC were done by TG/DTA coupled to GC-MS. The volatile material was identified as a series of straight chain of normal alkyl ranging from C3 to C10. This result indicated limitations of the apparatus employed n-alkyl chains longer than these were expected. However, it worked well for lighter components. Another experiment, in which gaseous products from pyrolysis procedure were recovered by bubbling in CH2Cl2, accounted for the heavier components. The solution obtained this time can be analyzed by syringe injection in a CG-MS. The majority of the volatile material is constituted of straight chain alkanes ranging from C13 to C33. Knowing more about the thermal decomposition conversion of asphaltenes, the solid pyrolysis products of them were obtained in larger quantities at 320, 380, 400, 440, 480, 550 e 580ºC. They were characterized by elemental analysis and solid state 13C nuclear magnetic resonance. It was observed that at higher pyrolysis temperatures, lower the hydrogen and aliphatic carbon contents were obtained for the solid products. So, to improve knowledge on these systems, asphaltenes and their solid products from thermal decomposition were oxidized with ruthenium (VIII) ion. The acids formed were mixed with excess of ethereal diazomethane and submitted to GC-MS in order to identify the correspondent methyl esters. It was observed three homologous series: methyl esters of linear carboxylic acids ranging from C6 to C27, corresponding to chain alkyl length from C5 to C26 substituent on aromatic carbon; small amounts of dimethyl esters were also present in a homologous series, ranging from C5 to C17 indicating bridge polymethylenes between aromatics from C3 to C15 and benzene dicarboxilic acids from C10 to C12. The total content of methyl ester of each reaction products was compared. It was observed that the linear esters content decreased slowly at a 320, 380, 400°C and drastically up to 400ºC. The same occurred with the dimethyl aliphatic esters and dimethyl benzyl esters.
139

De camaleão cultural a dragão transcultural: uma leitura de Silent dancing de Judith Ortiz Cofer

Schmitz, Virna Lúcia Coutinho 09 June 2008 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-02-22T14:56:20Z No. of bitstreams: 1 virnaluciacoutinhoschmitz.pdf: 922255 bytes, checksum: ba45c63ba22cbe1a566839a0513f85c0 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-02-22T15:13:51Z (GMT) No. of bitstreams: 1 virnaluciacoutinhoschmitz.pdf: 922255 bytes, checksum: ba45c63ba22cbe1a566839a0513f85c0 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-02-22T15:14:09Z (GMT) No. of bitstreams: 1 virnaluciacoutinhoschmitz.pdf: 922255 bytes, checksum: ba45c63ba22cbe1a566839a0513f85c0 (MD5) / Made available in DSpace on 2017-02-22T15:14:09Z (GMT). No. of bitstreams: 1 virnaluciacoutinhoschmitz.pdf: 922255 bytes, checksum: ba45c63ba22cbe1a566839a0513f85c0 (MD5) Previous issue date: 2008-06-09 / Este trabalho propõe uma leitura de Silent dancing: a partial remembrance of a Puerto Rican childhood, de Judith Ortiz Cofer, e investiga, principalmente, o percurso de formação identitária da narradora: de uma subjetividade em trânsito entre duas culturas, a porto-riquenha e a estadunidense, ao desenvolvimento de uma identidade transcultural. Ele tematiza a transformação da escritora de “camaleão cultural” em “dragão transcultural”. O estudo inclui, ainda, considerações sobre o gênero memorialístico e o imbricamento das línguas inglesa e espanhola presente no livro, além de realizar uma análise da pertinência da mistura de textos narrativos e poemas que se constata no livro. / This thesis proposes a reading of Silent dancing:a partial remembrance of a Puerto Rican childhood, by Judith Ortiz Cofer, and aims at investigating the process of its narrator’s identity, a bicultural subject shuttling between Puerto Rico and the United States of America, which develops into a transcultural identity. Besides examining the narrator’s transformation from a “cultural chameleon” into a “transcultural dragon”, the research analyzes its autobiographical aspect, the overlapping of the English and Spanish languages and also the mixture of narratives and poems present in the book.
140

Reassessing Consensus: Alejandro O’Reilly’s 1765 Visita and Puerto Rican History

Unknown Date (has links)
King Charles III of Spain implemented a series of Enlightenment reforms throughout his domain following the 1763 defeat of the Seven Years War Among the royal officials sent to enact these reforms in the Caribbean, the Crown dispatched Field Marshal Alejandro O’Reilly to the colony of Puerto Rico Historians have attributed to his 1765 inspection, or visita, and subsequent report, or memoria, the foundations for a turning point in the island’s history Despite the historical consensus that has lauded O’Reilly’s recommendations, this inspector-general does not merit the credit that historians consistently have given him Agrarian and economic patterns such as population growth, smuggling, and the hato economy persisted decades after his visita into the nineteenth century Other events helped drive immigration and investment into Puerto Rico more than O’Reilly’s memoria Ultimately, O’Reilly did not trigger enduring change in the colony’s history, and Puerto Rican historiography awaits the corresponding revision / Includes bibliography / Thesis (MA)--Florida Atlantic University, 2016 / FAU Electronic Theses and Dissertations Collection

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