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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.
31

Hwant wij binne it nijs ûnder en boppe de sinne

Gezelle Meerburg, Babs, January 1997 (has links)
Thesis (doctoral)--Rijksuniversiteit te Leiden, 1997. / Includes bibliographical references (p. 253-266).
32

The orthodoxy of the heart faith, fryslân, and feminism in novels of Ypk fan der Fear /

Hoekstra, Wiepk Johanna, January 1900 (has links)
Thesis (doctoral)--Rijksuniversiteit te Groningen, 1998. / Includes bibliographical references (p. 189-201).
33

Taal fan klerken en klanten undersyk nei it Frysk en it Nederlânsk yn it ferkear tusken siktary-amtners en ynwenners fan de gemeente Hearrenfean /

Gorter, D. January 1900 (has links)
Thesis (doctoral)--Universiteit Amsterdam, 1993. / "Stellingen" laid in. Includes bibliographical references (p. 312-330).
34

Frisian as first and second language sociolinguistic and socio-psychological aspects of the acquisition of Frisian among Frisian and Dutch primary school children /

Ytsma, Jehannes. January 1995 (has links)
Thesis (doctoral)--Katholieke Universiteit Brabant, 1995. / "Stellingen" laid in. Summaries in Dutch and Frisian. Includes bibliographical references (p. 195-208).
35

Fotoquímica de carbamatos aromáticos e derivados por métodos de estrutura eletrônica : do rearranjo foto-fries à fotodegradação de pesticidas

Toldo, Josene Maria January 2017 (has links)
A fotodegradação de pesticidas, como os derivados de carbamatos orgânicos, possui um papel importante do ponto de vista ambiental, pois estes são extensivamente utilizados e comumente encontrados como contaminantes da água e do solo. O Rearranjo Foto-Fries (PFR) - a conversão fotoquímica de aril ésteres para orto- e para-hidroxifenonas - desempenha um importante papel na fotodegradação de drogas e pesticidas carbamatos, além de ser um passo chave para a síntese de um grande número de compostos e polímeros funcionais. Embora exista um grande número de estudos experimentais a respeito desse rearranjo, alguns pontos dessa reação ainda estão sob debate. O objetivo deste trabalho é estudar o processo de fotodissociação em carbamatos aromáticos e derivados e, particularmente, fornecer uma visão geral do mecanismo do Rearranjo Foto-Fries, utilizando metodologias computacionais. Entre essas metodologias estão TDDFT, cálculos multiconfiguracionais e Surface Hopping. A superfície de energia potencial para o PFR foi estudada no vácuo gasosa e utilizando solvatação implícita e explícita. Nessa última, a distribuição do solvente foi obtida por simulações de Monte Carlo. Um modelo envolvendo três estados é proposto para o PFR, baseado em cálculos CASSCF(14,12)/CASPT2(14,12). Este modelo fornece uma visão global de todos os passos envolvidos na reação, da fotodissociação até a tautomerização final. O papel do solvente ainda não foi esclarecido, pois a sua adição (implícita ou explícita) não alterou significativamente o comportamento do caminho dissociativo. / The photodegradation of pesticides, such as carbamate derivatives, has an environmentally important role, since they are extensively used and commonly found as contaminants in water and soils. The Photo-Fries rearrangement (PFR) - a photochemical conversion of aryl esters to ortho- and para-hydroxyphenones - plays an important role in the photodegradation of drugs and carbamate pesticides, besides being a key step in the synthesis of a large number of compounds and functional polymers. Although there is a large number of experimental studies about the mechanism of PFR, some points of this reaction are still under debate. The goal of this work is to study the photodissociation process in aromatic carbamates and derivatives and, particularly, is to provide a comprehensive picture of PFR, based on computational methods. Several methodologies were used, such as TDDFT, multiconfigurational methods and Trajectory Surface Hopping simulations. Comprehensive explorations of the potential energy surfaces were done in the gas phase and with implicit and explicit solvent, whose distribution was obtained from sequential Monte Carlo sampling. A three-state model for the Photo-Fries Rearrangement is proposed based on CASSCF(14,12)/CASPT2(14,12) calculations. It provides a comprehensive mechanistic picture of all steps of the reaction, from the photoabsorption to the final tautomerization. The role of the solvent is still not understood since the addition of solvent (implicit or explicit) do not change the dissociative pathway significantly.
36

Fotoquímica de carbamatos aromáticos e derivados por métodos de estrutura eletrônica : do rearranjo foto-fries à fotodegradação de pesticidas

Toldo, Josene Maria January 2017 (has links)
A fotodegradação de pesticidas, como os derivados de carbamatos orgânicos, possui um papel importante do ponto de vista ambiental, pois estes são extensivamente utilizados e comumente encontrados como contaminantes da água e do solo. O Rearranjo Foto-Fries (PFR) - a conversão fotoquímica de aril ésteres para orto- e para-hidroxifenonas - desempenha um importante papel na fotodegradação de drogas e pesticidas carbamatos, além de ser um passo chave para a síntese de um grande número de compostos e polímeros funcionais. Embora exista um grande número de estudos experimentais a respeito desse rearranjo, alguns pontos dessa reação ainda estão sob debate. O objetivo deste trabalho é estudar o processo de fotodissociação em carbamatos aromáticos e derivados e, particularmente, fornecer uma visão geral do mecanismo do Rearranjo Foto-Fries, utilizando metodologias computacionais. Entre essas metodologias estão TDDFT, cálculos multiconfiguracionais e Surface Hopping. A superfície de energia potencial para o PFR foi estudada no vácuo gasosa e utilizando solvatação implícita e explícita. Nessa última, a distribuição do solvente foi obtida por simulações de Monte Carlo. Um modelo envolvendo três estados é proposto para o PFR, baseado em cálculos CASSCF(14,12)/CASPT2(14,12). Este modelo fornece uma visão global de todos os passos envolvidos na reação, da fotodissociação até a tautomerização final. O papel do solvente ainda não foi esclarecido, pois a sua adição (implícita ou explícita) não alterou significativamente o comportamento do caminho dissociativo. / The photodegradation of pesticides, such as carbamate derivatives, has an environmentally important role, since they are extensively used and commonly found as contaminants in water and soils. The Photo-Fries rearrangement (PFR) - a photochemical conversion of aryl esters to ortho- and para-hydroxyphenones - plays an important role in the photodegradation of drugs and carbamate pesticides, besides being a key step in the synthesis of a large number of compounds and functional polymers. Although there is a large number of experimental studies about the mechanism of PFR, some points of this reaction are still under debate. The goal of this work is to study the photodissociation process in aromatic carbamates and derivatives and, particularly, is to provide a comprehensive picture of PFR, based on computational methods. Several methodologies were used, such as TDDFT, multiconfigurational methods and Trajectory Surface Hopping simulations. Comprehensive explorations of the potential energy surfaces were done in the gas phase and with implicit and explicit solvent, whose distribution was obtained from sequential Monte Carlo sampling. A three-state model for the Photo-Fries Rearrangement is proposed based on CASSCF(14,12)/CASPT2(14,12) calculations. It provides a comprehensive mechanistic picture of all steps of the reaction, from the photoabsorption to the final tautomerization. The role of the solvent is still not understood since the addition of solvent (implicit or explicit) do not change the dissociative pathway significantly.
37

Proteïnes com a microreactors en fotoquímica supramolecular

Marín Melchor, Mireia 20 February 2013 (has links)
La fotoquímica supramolecular es una herramienta muy utilizada para controlar la selectividad, la reactividad y el avance de las reacciones químicas. Con ella se aprovecha la estructura tridimensional del anfitrión para canalizar la conformación de los estados excitados de los sustratos que intervienen en la reacción. En la literatura se encuentran numerosos casos de fotorreacciones catalizadas por supramoléculas abióticas, pero los ejemplos con biomoléculas son escasos. En este contexto, el objetivo de la presente tesis ha sido estudiar reacciones fotoquímicas clásicas en el seno de biomoléculas ya que éstas pueden presentar ventajas respecto a las supramoléculas abióticas. Se han escogido las albúminas séricas como anfitriones bióticos, en base a dos propiedades claves: (i) son proteínas transportadoras que actúan como vehículo de una amplia variedad de sustancias; (ii) poseen dos sitios de unión diferenciados: el sitio I y el sitio II. La reorganización de foto-Fries fue la primera reacción abordada. Para ello se diseñaron varios sustratos que interaccionaban en los sitios de unión I y II de distintas albúminas. Distintos estudios cinéticos demostraron que los rendimientos de formación de los fotoproductos dependían del sitio de interacción y de la clase de albúmina utilizada. Se seleccionaron también derivados de avobenzona (AB) sustituídos en la posición ? de los carbonilos. Se demostró que éstos sólo existen bajo su forma ?-dicetónica, la cual puede desencadenar procesos de fototoxicidad. Se estudió mediante fotólisis de destello láser el efecto de la interacción de los tres derivados con HSA y los resultados mostraron el efecto protector de ésta frente al ataque por oxígeno y la auto-desactivación y reflejaron el entorno confinado proporcionado por la albúmina. Además, se investigó la fragmentación de Norrish tipo II de uno de los derivados, que resultó ser más lenta en presencia de albúmina. Por último, se consideró la fotoelectrociclación [6?] de la N- / Marín Melchor, M. (2013). Proteïnes com a microreactors en fotoquímica supramolecular [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/27204 / Palancia
38

Minns du Herr Kantarell? : En innehållsanalys av historiekulturen kring Elias Magnus Fries i svenska tidningsartiklar mellan 1970–2019 / Do you remember Mr. Chanterelle? : A content analysis of the cultural memory of Elias Magnus Fries in Swedish newspapers between 1970–2019

Knutsson, Sebastian January 2019 (has links)
The aim of this study is to analyze the botanist Elias Magnus Fries legacy between 1970 until today. The focus is on the Swedish medias interest in Fries, as well as how he and his name has been utilized during this period. Departing from theories on history culture and uses of history, the Swedish national newspapers Aftonbladet, Dagens Nyheter, Expressen and Svenska Dagbladet are analyzed. The study shows when and how the memory of Elias Magnus Fries has been activated and portrayed in Swedish media, as well as if they used Fries as a kind of national symbol. During the 1970’s the interest was at its peak but dwindled after the 90’s probable due to the lack of jubilee celebration. Indeed, the interest of Fries peaked during the 70’s and 90’s because of celebrating the 100-year celebration of his death in 1878 and the 200 anniversary of his birth in 1794. Although, the general view of Fries persona always has been positive, rather scant attention har been devoted to Fries during the entire period and he was often only mentioned briefly. The interest was in general primarily on mushrooms rather than Fries, and it was always the mushrooms that spurred an interest in Fries rather than the other way around. This might indicate a rather weak position in the history of science within Swedish media. Nevertheless, the newspapers also depicted Fries as a kind of national educator, scientist and a person with a great an evolutionistic mind for his great interest in mushrooms and its introduction in the Swedish cuisine.
39

Structural framework of the Fries fault zone south of Riner, Virginia

Whitmarsh, Richard Sawyer 12 September 2009 (has links)
The Fries fault zone south of Riner, Virginia is marked by a ductile, greenschist-facies thrust that places Middle Proterozoic gneiss over deformed Late Proterozoic(?)—Early Paleozoic rocks of the western Blue Ridge province. This work presents an analysis of the field relationships and finite strain patterns within the fault zone, and further relates these features to an interpretation of its structural framework. A geologic map of the fault zone is provided, in addition to more detailed lithologic descriptions within the text. Noteworthy aspects of the field geology include: (1) the discovery of a reasonable protolith to the mylonitic Little River Gneiss, which could previously only be inferred; and (2) the recognition of a varied lithologic assemblage that is considered to be correlative with the Pilot Gneiss, which is exposed along strike within the Brush Creek anticlinorium. Kinematic analysis of tectonic fabrics within the Little River Gneiss, Pilot Gneiss, and Chilhowee Group suggest that the fault zone developed in response to southeast—northwest shortening, accommodated by general noncoaxial flow, which produced a top-to-the-northwest sense of shear at all scales of observation. However, it is evident that the original stratigraphic anisotropy within the Chilhowee Group effectively partitioned the coaxial and noncoaxial components of strain. Additional finite strain analyses within the Chilhowee Group, including the correlation of R<sub>f</sub>/Ø data with quartz c-axis fabrics, indicate that there is considerable variation in the geometry of finite strain along the fault zone. Whereas flattening strains appear to predominate, it is evident that domains of constructional strain and plane strain are localized near the nose of the Brush Creek anticlinorium. These data are considered to support an interpretation in which the Pilot Gneiss and Chilhowee Group were metamorphosed and folded into a doubly-plunging antiform during the Taconic orogeny (ca. 480-435 Ma), and that progressive shortening of the Laurentian continental margin during this interval caused the Little River Gneiss to be uplifted along the Fries fault. The present structural framework of the Fries fault zone south of Riner, Virginia is thus considered to represent a northwest-vergent fold composed of Late Proterozoic—early Paleozoic strata, which is transected by the base of the Little River Gneiss. / Master of Science
40

Características químicas e fisiológicas de frutos de crambe cultivados com aplicação de reguladores vegetais / Chemical and physiological characteristics of crambe fruits cultivated with plant growth regulators

Boiago, Nayara Parisoto 19 June 2017 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-05-29T14:50:49Z No. of bitstreams: 2 NAYARA PARISOTO BOIAGO.pdf: 1163745 bytes, checksum: 6ae0a0dea2680203a2663f070879ddcb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-05-29T14:50:49Z (GMT). No. of bitstreams: 2 NAYARA PARISOTO BOIAGO.pdf: 1163745 bytes, checksum: 6ae0a0dea2680203a2663f070879ddcb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Plant growth regulators (PGRs) can be applied in agricultural crops improving their development and, consequently, improves the quality of grains and seeds produced. This work aimed to evaluate the effect of foliar application of PGRs on crambe fruits quality grown in 2014 and 2015 harvests.When crambe plants were in transition from vegetative stage to flowering, indole-3-acetic 100 mg L-1 (IAA), 3-gibberellic acid P.A. 100 mg L-1 (GA3); commercial PGR Stimulate® 6 mL L-1 and a control treatment with distilled water were applicated in two 15-day intervals. Fruits produced by treated plants were harvested and prepared for further analyzes. For the post-harvest chemical quality analyzes, grains of each treatment with PGRs were stored at ambient conditions for 180 days and the parameters were analyzed at the beginning and at the end of storage. Water content, lipids by cold extraction (CE), lipids by heated extraction (HE), protein, acidity and antioxidant activity (AA) of crambe grains were determined and the significant difference between averages in three-way ANOVA (harvest year x PGR x storage) were compared by the Tukey test (p<0.05). A cluster analyzes was also performed to identify similarities between the chemical parameters studied. In the experimental stage regarding the physiological quality of crambe, seeds produced with PGR were analyzed by their percentage and germination speed index (GSI), moisture content, electrical conductivity (EC) and quantification of K, Ca and Mg leached. Treatments were compared with each other Tukey test and with control by Dunnett test (p<0,05). Grains stored for 180 days showed lower lipid CE and HE content. However, under the application of PGR, lipids content and AA did not change with storage, and grains acidity reduced. There was difference in each PGR effects between the harvests studied. In 2014, the application of IAA promoted improved results regarding grains quality, while in 2015, GA3 and Stimulate® stood out. PGR application also influenced the physiological quality of crambe seeds. The application of Stimulate® increased germination percentage and GSI, while IAA reduced germination, GSI and increased EC of crambe seeds. Seeds produced with IAA showed lower leaching of Ca and all the applied PGR reduced K leaching of crambe seeds. It is concluded that the foliar application of PGR culminates in effects on crambe quality and may be used as a management technique in order to improve post harvest quality of this crop. / Os reguladores vegetais (RV) podem agir nas culturas agrícolas melhorando seu desenvolvimento vegetal e, consequentemente, a qualidade dos grãos/sementes produzidos. Assim, este trabalho teve como objetivo avaliar o efeito da aplicação foliar de RV na qualidade de frutos de crambe cultivados em 2014 e 2015. Quando as plantas de crambe estavam em transição do estádio vegetativo para floração, realizou-se duas aplicações espaçadas por 15 dias de ácido indol-3-acético 100 mg L-1 (AIA), ácido 3-giberélico P.A. 100 mg L-1 (GA3); regulador vegetal comercial Stimulate® 6 mL L-1 e um tratamento controle com aplicação de água destilada. Os frutos produzidos pelas plantas tratadas foram colhidos e separados para demais análises. Para as análises de qualidade química na pós-colheita, os grãos referentes a cada tratamento com reguladores foram armazenados em condições ambientes por 180 dias e os parâmetros avaliados no início e no final do armazenamento. Os teores de água, lipídios por extração a quente (EQ), lipídios por extração a frio (EF), proteína, acidez e atividade antioxidante (AA) dos grãos foram determinados, e as diferenças significativas entre as médias na ANOVA trifatorial (safra x RV x armazenamento) foram comparadas pelo teste Tukey (p<0,05). Uma análise de agrupamento também foi realizada para identificar as similaridades entre os parâmetros químicos estudados. Na etapa experimental, que diz respeito à qualidade fisiológica de crambe, as sementes produzidas com RV foram analisadas no teste de porcentagem e índice de velocidade de germinação (IVG), teor de umidade, condutividade elétrica (CE) e quantificação de K, Ca e Mg lixiviados. Os tratamentos foram comparados entre si pelo teste Tukey e com o controle pelo teste Dunnett (p<0,05). Os grãos armazenados por 180 dias apresentaram menor teor de lipídeos EF e EQ. Entretanto, perante a aplicação de RV, o teor de lipídeos e a AA não se alterou com a armazenagem, e a acidez nos grãos reduziu. Houve diferença entre as safras no que diz respeito ao desempenho de cada RV. Em 2014, a aplicação de AIA promoveu resultados vantajosos em relação à qualidade dos grãos, enquanto que em 2015 destaca-se GA3 e o Stimulate®. A aplicação de reguladores também influenciou a qualidade fisiológica de sementes de crambe. Perante aplicação de Stimulate® houve aumento da porcentagem de germinação e do IVG, já o AIA reduziu a germinação, o IVG e aumentou a CE das sementes. As sementes produzidas com aplicação de AIA apresentaram menor lixiviação de Ca e todos os reguladores aplicados reduziram a lixiviação de K de sementes de crambe. Conclui-se que a aplicação de RV culmina em efeitos na qualidade do crambe e pode ser utilizada como técnica de manejo a fim melhorar a qualidade pós-colheita dessa cultura.

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