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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.
101

Preparation of Pd-Ag/PSS composite membranes for hydrogen separation

Akis, B. Ceylan. January 2004 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Hydrogen Permeation; Pd-Ag Membranes; Electroless Plating. Includes bibliographical references (p. 114-118).
102

Theory and practice in the coining and transmission of place-names : a study of the Norse and Gaelic anthropo-toponyms of Lewis

Evemalm, Sofia January 2018 (has links)
The study of place-names containing personal names is a neglected field in onomastics, despite being of great significance in various areas of name-studies. At its core, this thesis will begin to bridge the gap between the study of place-names and personal names, both practically and theoretically. The first step is to introduce a formally accepted terminology for the study of these names. Here, the term used to describe a place-name containing a personal name is anthropo-toponym. The acknowledgement of such a term would aid and indeed encourage future studies of anthropo-toponyms, both in Scotland and elsewhere. The study is approached through a close investigation of name material from the Isle of Lewis. The toponyms in question are characterised by two main linguistic layers, Old Norse and Scottish Gaelic, both of which have been included here. Although this material is partially an exercise in investigating the characteristics and properties of anthropo-toponyms, it also sheds considerable light on the social and linguistic history of Lewis place-names. Additionally, the study draws on a considerable amount of comparative evidence. This is primarily collected from the comprehensive survey of The Place-Names of Fife by Simon Taylor with Gilbert Márkus (2006-12). However, when studying the Norse dimension further, material from Landnámabók, one of the key sources for the medieval settlement of Iceland, has also been included. One of the most significant proposals made in this thesis is the concept of using a variant of the name-semantic approach, previously discussed by Peder Gammeltoft (2001a) in a Scottish context. At its core, this means that rather than emphasising the etymology of individual place-name elements, the motivation for coining is emphasised. It will become evident that using this approach makes it possible to view anthropo-toponyms in a different light. Through this method, we find that there is considerable variety to be found within the name-material, particularly when we look at the social and cognitive factors at play when place-names are coined and transmitted. Place-names that, on the surface appear to be relatively homogenous, can prove to be the opposite. For example, names such as Creagan Iain Ruaidh, Geodha Bean, Mhurchaidh, Stac Dhomhnuill Chaim and Tigh Mhaoldònuich, which are all coined in a comparable social Gaelic setting in the early modern period, appear to represent motivations relating to a birth, a drowning, the abode of a notorious outlaw, and the temporary hideout of a sheep thief respectively. By emphasising these micro-narratives, it is possible to shed light on the name material from a new perspective and to provide a greater understanding of the process of coining place-names.
103

The written rune : alphabets and rune-rows in medieval manuscripts from the Continent and the British Isles

Van Renterghem, A. M. S. January 2018 (has links)
This thesis aims to create a fundamental historical and geographical framework for the study of runes written in medieval manuscripts. It does so by examining the transmission of Anglo-Saxon and Scandinavian rune-rows and runic alphabets within the wider context of contemporary medieval scholarship. The focal points of this study are the questions of the origin of the phenomenon, and how it developed between the eighth and the twelfth centuries, as evidenced by manuscripts currently held by continental and English libraries. In order to contextualise this study, a brief introduction is dedicated to the concept of runic manuscripts and to an overview of the scholarship which has been carried out on this material thus far. The observations from this discussion are then used to define the limitations of this work. Finally, a number of the issues currently faced by scholars with regard to defining the field of manuscript runology are examined, and the comparison with its epigraphical counterpart is made. The study includes thirty-nine manuscripts with alphabets or rune-rows; these are listed and described in a catalogue which comprises the main body of the thesis. Each manuscript receives a description of its history and contents, an analysis of the runic material it contains, and an examination of the immediate and wider contexts in which the runes appear. The information gathered in the catalogue is collectively analysed in the final chapter, which focuses on determining the origin and development of the phenomenon of runes in manuscripts. The examination of origin uses commonalities between the contexts of the runes to achieve insight into the medieval perception of manuscript runes, and to construct a possible point of origin. The development section then follows the evolution of the tradition and compares and contrasts its execution on the Continent and in the British Isles. Finally, these results are used to indicate the place of written runes within medieval learning, and to construct a general framework which can be used to build upon for future research.
104

Potencialidades biológicas e aspectos estruturais de compostos contendo paládio(II) e isonicotinamida

Souza, Rodrigo Alves de [UNESP] 15 August 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-15Bitstream added on 2014-06-13T19:38:13Z : No. of bitstreams: 1 souza_ra_me_araiq.pdf: 2538432 bytes, checksum: 3b82e3741e1179ffc530cdc631ba9c10 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho trata da síntese, caracterização estrutural e aplicações biológicas de quatro complexos de paládio(II), de fórmula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3) e NCO (4), isn= isonicotinamida. Os compostos foram preparados em mistura de CHCl3/ CH3OH (1:1), partindo-se do precursor [PdCl2(CH3CN)2] que reagiu com a isn e sais de pseudohaletos: NaN3, KNCO e NaSCN. A caracterização destes complexos, no estado sólido, se deu pelas técnicas de análise elementar, espectroscopia de absorção no infravermelho, análise térmica e difração de raios X de monocristal do composto 2, possibilitando sugerir estruturas monoméricas, com a isn coordenada ao Pd pelo nitrogênio piridínico. Cloro e os pseudohaletos acham-se coordenados de modo terminal, via nitrogênio em 2 e em 4 e pelo átomo de enxofre em 3. As curvas TG substanciaram as propostas estequiométricas e permitiram estabelecer, com base na temperatura inicial de decomposição, a seguinte ordem de estabilidade térmica para esta série: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. A estrutura do complexo 2 foi resolvida por difração de raios X de monocristal, e apresenta uma geometria quadrado-planar ao redor do Pd e estereoquímica trans. Nota-se ainda, que a estrutura se estende por ligações intermoleculares de hidrogênios, formando arranjos supramoleculares bidimensionais via N– H...O e arranjos tridimensionais, decorrentes de interações C–H...Nazida. Os dados de RMN em solução confirmam a formação dos complexos, constatando-se, além disso, a presença de outras espécies químicas em solução. A ação antiproliferativa dos compostos contra células tumorais de mama, LM3, e pulmão, LP07, foi investigada. A atividade da isn foi desprezível e os valores de IC50 dos complexos foram maiores que os apresentados pela cisplatina... / The present work deals with the synthesis, structural characterization and biological applications of four palladium(II) complexes, of formula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3), and NCO (4), isn = isonicotinamide. The compounds were prepared in mixture of CHCl3/ CH3OH (1:1), from precursor [PdCl2(CH3CN)2] that reacted with isn and pseudohalide salts: NaN3, KNCO e NaSCN. The characterization of these complexes, in solid state, occurred by techniques of elemental analysis, infrared spectroscopy absorption, thermal analysis, and X-rays diffraction of single crystal of the compound 2, making possible to suggest monomeric structures containing the isn coordinated to Pd by pyridinic nitrogen. Chlorine and pseudohalides are coordinated of terminal way, by nitrogen in 2 and 4, and by sulphur atom in 3. The TG curves substantiated the stoichiometric proposals and made possible to establish, based on initial temperature of decomposition, the following order of thermal stability to this series: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. The structure of the complex 2 was solved by Xrays diffraction of single crystal, and shows a square-planar geometry around Pd and trans stereochemistry. It is even noticed that the structure is prolonged to hydrogen intermolecular bonds, forming bidimensional supramolecular arrays by N–H...O and tridimensional arrays, resulting from C–H...Nazide interactions. NMR data in solution confirm the formation of the complexes, noticing as well as the presence of other chemical species. It was investigated the antiproliferactive action of compounds against breast tumor cells, LM3, and lung tumor cells, LP07. The activity of isn was irrelevant and IC50 values of the complexes were higher than the ones showed by cisplatin. However, the complexes showed to be more selective than cisplatin when tested... (Complete abstract click electronic access below)
105

Investigação das potencialidades de complexos pirazólicos de Pd (II) no desenvolvimento de novas metalo-drogas /

Barra, Carolina Valério. January 2010 (has links)
Resumo: A quimioterapia é uma das principais formas de combate ao câncer. Sendo assim, muitas pesquisas vêm sendo feitas com o objetivo de desenvolver compostos que solucionem, ou minimizem, os problemas decorrentes deste tipo de tratamento, como os efeitos colaterais e a resistência que as células desenvolvem aos medicamentos. Os pirazóis e seus complexos são conhecidos por possuírem atividade antitumoral, antiinflamatória, antibacteriana e antipirética. Tendo em vista estas propriedades, ligantes pirazólicos foram utilizados na síntese de complexos de paládio(II) com a finalidade de obter compostos com atividade antitumoral. A escolha deste metal foi baseada na similaridade entre sua química de coordenação e a da platina(II), cujos complexos, como a cisplatina e a carboplatina, são amplamente utilizados como agentes antitumorais. Neste contexto, o presente trabalho descreve a síntese, caracterização e avaliação da atividade antitumoral de duas séries de compostos paládio(II) de fórmula geral [PdX2(HdmIPz)2] {HdmIPz = 3,5-dimetil-4-iodopirazol; X = Cl (1), Br (2), I (3), SCN (4)} e [PdX2(HmPz)2] {HmPz =4-metilpirazol; X = Cl (5), Br (6), I (7), SCN (8)}. Os compostos foram caracterizados por análise elementar, espectroscopia vibracional na região do infravermelho, ressonância magnética nuclear de 1 H e 13 C{ 1 H}, termogravimetria e análise térmica diferencial. Os complexos sintetizados e os ligantes livres foram submetidos a testes de atividade citotóxica frente a células tumorais murinas. A cisplatina foi usada como droga padrão, sendo submetida às mesmas condições. A citotoxicidade dos compostos 1-4 também foi avaliada frente a macrófagos peritoneais de camundongos / Abstract: Chemotherapy is one of the main methods of treating cancer. Thus, much research has been undertaken with the aim of developing compounds that can solve or minimize the problems caused by this type of treatment, as the side effects and cell resistance. Pyrazoles and their complexes are known to possess antitumor, anti-inflammatory, antiamoebic, antibacterial, antipyretic activities. Considering these properties, pyrazole ligands were used in the synthesis of palladium(II) complexes with the aim to obtain compounds displaying antitumor activity. The choice for using this metal was based on the similarity of its coordination chemistry to that of platinum(II) whose compounds, such as cisplatin and carboplatin, are widely used as antitumor agents. In this context, this work describes the synthesis, characterization and investigation of the antitumor activity of two series of palladium(II) complexes of general formulae [PdX2(HdmIPz)2] {HdmIPz = 3,5-dimethyl-4-iodopyrazole; X = Cl (1), Br (2), I (3), SCN (4)} e [PdX2(HmPz)2] {HmPz =4-methylpyrazole; X = Cl (5), Br (6), I (7), SCN (8)}. The compounds were characterized by elemental analysis, infrared vibrational spectroscopy, 1 H and 13 C{ 1 H} nuclear magnetic resonance, thermogravimetry and differential thermal analysis. The complexes and the free ligands were tested for cytotoxic activity against murine tumor cells. Cisplatin was used as standard drug, being subject to the same conditions. The cytotoxicity of compounds 1-4 was also evaluated towards peritoneal macrophages of mice / Orientador: Adelino Vieira de Godoy Netto / Coorientador: Antonio Eduardo Mauro / Banca: Pedro Paulo Corbi / Banca: Wagner Ferraresi de Giovani / Mestre
106

Potencialidades biológicas e aspectos estruturais de compostos contendo paládio(II) e isonicotinamida /

Souza, Rodrigo Alves de. January 2008 (has links)
Resumo: O presente trabalho trata da síntese, caracterização estrutural e aplicações biológicas de quatro complexos de paládio(II), de fórmula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3) e NCO (4), isn= isonicotinamida. Os compostos foram preparados em mistura de CHCl3/ CH3OH (1:1), partindo-se do precursor [PdCl2(CH3CN)2] que reagiu com a isn e sais de pseudohaletos: NaN3, KNCO e NaSCN. A caracterização destes complexos, no estado sólido, se deu pelas técnicas de análise elementar, espectroscopia de absorção no infravermelho, análise térmica e difração de raios X de monocristal do composto 2, possibilitando sugerir estruturas monoméricas, com a isn coordenada ao Pd pelo nitrogênio piridínico. Cloro e os pseudohaletos acham-se coordenados de modo terminal, via nitrogênio em 2 e em 4 e pelo átomo de enxofre em 3. As curvas TG substanciaram as propostas estequiométricas e permitiram estabelecer, com base na temperatura inicial de decomposição, a seguinte ordem de estabilidade térmica para esta série: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. A estrutura do complexo 2 foi resolvida por difração de raios X de monocristal, e apresenta uma geometria quadrado-planar ao redor do Pd e estereoquímica trans. Nota-se ainda, que a estrutura se estende por ligações intermoleculares de hidrogênios, formando arranjos supramoleculares bidimensionais via N- H...O e arranjos tridimensionais, decorrentes de interações C-H...Nazida. Os dados de RMN em solução confirmam a formação dos complexos, constatando-se, além disso, a presença de outras espécies químicas em solução. A ação antiproliferativa dos compostos contra células tumorais de mama, LM3, e pulmão, LP07, foi investigada. A atividade da isn foi desprezível e os valores de IC50 dos complexos foram maiores que os apresentados pela cisplatina... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work deals with the synthesis, structural characterization and biological applications of four palladium(II) complexes, of formula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3), and NCO (4), isn = isonicotinamide. The compounds were prepared in mixture of CHCl3/ CH3OH (1:1), from precursor [PdCl2(CH3CN)2] that reacted with isn and pseudohalide salts: NaN3, KNCO e NaSCN. The characterization of these complexes, in solid state, occurred by techniques of elemental analysis, infrared spectroscopy absorption, thermal analysis, and X-rays diffraction of single crystal of the compound 2, making possible to suggest monomeric structures containing the isn coordinated to Pd by pyridinic nitrogen. Chlorine and pseudohalides are coordinated of terminal way, by nitrogen in 2 and 4, and by sulphur atom in 3. The TG curves substantiated the stoichiometric proposals and made possible to establish, based on initial temperature of decomposition, the following order of thermal stability to this series: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. The structure of the complex 2 was solved by Xrays diffraction of single crystal, and shows a square-planar geometry around Pd and trans stereochemistry. It is even noticed that the structure is prolonged to hydrogen intermolecular bonds, forming bidimensional supramolecular arrays by N-H...O and tridimensional arrays, resulting from C-H...Nazide interactions. NMR data in solution confirm the formation of the complexes, noticing as well as the presence of other chemical species. It was investigated the antiproliferactive action of compounds against breast tumor cells, LM3, and lung tumor cells, LP07. The activity of isn was irrelevant and IC50 values of the complexes were higher than the ones showed by cisplatin. However, the complexes showed to be more selective than cisplatin when tested... (Complete abstract click electronic access below) / Orientador: Antonio Eduardo Mauro / Coorientador: Adelino Vieira de Godoy Netto / Banca: Luiz Antonio Andrade de Oliveira / Banca: Denise de Oliveira Silva / Mestre
107

Det virtuella ärendet : en storbildsvision för arbete på ett samhällsbyggnadskontor / The virtual errand : a large-screen vision för work in a planning department

Winter, Jeff January 2003 (has links)
Denna rapport handlar om arbetet med detaljplaner på ett Samhällsbyggnadskontor. Den försöker svara på två frågor. Hur kan man designa integration av olika applikationer, medier och work practices? Är metoder från Participatory Design (PD), Etnografi och CSCW lämpliga för att utforma en sådan designprocess? I min studie har jag använt mig av dessa metoder för att studera arbetet i sin kontext på kontoret, genom situerade intervjuer och observationer. Jag höll även en designworkshop tillsammans med några medarbetare på kontoret. För att klargöra bakgrunden till mina frågor presen-terar jag teorier om PD, CSCW och e-government, och jag försöker relatera mina forskningsfrågor till dessa teorier. Jag presenterar också mitt empiriska material, för att visa bakgrunden till mina slutsatser. Jag har spelat en aktiv roll i projektet, både som ”Action Researcher” och som designer. Action Research är en reflexiv process, där reflektioner över materialet och processen under arbetets gång påverkar själva arbetet. Jag upptäckte vissa svårigheter att arbeta på det sättet, eftersom arbetet uppdelades på två olika nivåer, och det var svårt att hålla isär mina olika roller i projektet, som ”Action Researcher” och som designer. Jag kom fram till att integrationen inte är en fråga om tekniska möjligheter, utan är en fråga om att få teknologin att passa in i själva arbetet, för att stödja work practice. Mitt arbete resulterade i en vision för ett system för detaljplanering som jag presenterar i scenario-form. Visionen innehåller många punkter som bör beaktas i systemdesign i ett sådant fall. Jag kom också fram till att metoder från PD, CSCW och Etnografi är väl lämpade för att informera designprocessen i en miljö som kännetecknas av kooperation, kommunikation, distribuerat arbete, mobilitet, och en kombination av många olika medier.
108

Mindstorm

Jiang, Chun hui, Mao, Yu jiao January 2011 (has links)
Since the mindstorm kit is widely used by students and beginners, demand of a commercial-free integrated embedded working environment turns up. With its help the limitation on working place and complexity of programming can be reduced.  The aim of this project is to use a combination of commercial-free softwares as an embedded working environment. The environment can deal with the mindstorm kit applications directly. In order to show the successful generation of the commercial-freesoftware's project an inverted pendulum is set up. Open source firmware of NXT-G is used to provide basic interface for invoking the functions in NXT master brick. Accelerometer is working as the sensor. The main dynamic controller falls on the PD controller to keep inverted pendulum in vertical and static state. As a result the inverted pendulum programmed in this working environment can keep balance for a couple of seconds.
109

Vernacular psychologies in Old Norse-Icelandic and Old English

Mackenzie, Colin Peter January 2014 (has links)
This thesis examines the vernacular psychology presented in Old Norse-Icelandic texts. It focuses on the concept 'hugr', generally rendered in English as ‘mind, soul, spirit’, and explores the conceptual relationships between emotion, cognition and the body. It argues that despite broad similarities, Old Norse-Icelandic and Old English vernacular psychology differ more than has previously been acknowledged. Furthermore, it shows that the psychology of Old Norse-Icelandic has less in common with its circumpolar neighbours than proposed by advocates of Old Norse-Icelandic shamanism. The thesis offers a fresh interpretation of Old Norse-Icelandic psychology which does not rely on cross-cultural evidence from other Germanic or circumpolar traditions. In particular, I demonstrate that emotion and cognition were not conceived of ‘hydraulically’ as was the case in Old English, and that 'hugr' was not thought to leave the body either in animal form or as a person’s breath. I show that Old Norse-Icelandic psychology differs from the Old English tradition, and argue that the Old English psychological model is a specific elaboration of the shared psychological inheritance of Germanic whose origins require further study. These differences between the two languages have implications for the study of psychological concepts in Proto-Germanic, as I argue that there are fewer semantic components which can be reliably reconstructed for the common ancestor of the North and West Germanic languages. As a whole, the thesis applies insights from cross-cultural linguistics and psychology in order to show how Old Norse-Icelandic psychological concepts differ not only from contemporary Germanic and circumpolar traditions but also from the Present Day English concepts used to describe them. The thesis comprises four chapters and conclusion. Chapter 1 introduces the field of study and presents the methodologies and sources used. It introduces the range of cross-cultural variety in psychological concepts, and places Old Norse-Icelandic 'hugr' and its Old English analogue 'mōd' in a typological perspective. Chapter 2 reviews previous approaches to early Germanic psychology and introduces the major strand of research that forms the background to this study: Lockett’s (2011) proposal that Old English vernacular psychology operated in terms of a ‘hydraulic model’, where the 'mōd' would literally boil and seethe within a person’s chest in response to strong emotions. Chapter 3 outlines the native Old Norse-Icelandic psychological model by examining indigenously produced vernacular texts. It looks first at the claims that 'hugr' could leave the body in animal form or as a person’s breath. It then describes the relationship between emotion, cognition and the body in Old Norse-Icelandic texts and contrasts this with the Old English system. Chapter 4 examines the foreign influences which could potentially account for the differences between the Old English and Old Norse-Icelandic systems. It looks first at the imported medical traditions which were known in medieval Scandinavia at the time Old Norse-Icelandic texts were being committed to writing. Next it considers the psychology of Christian tradition from the early Old Icelandic Homily Book to late-fourteenth-century devotional poetry. Finally, it examines the representation of emotion and the body in the translated Anglo-Norman and Old French texts produced at the court of Hákon Hákonarson and explores how this was transposed to native romances composed in Old Norse-Icelandic. The conclusion summarises the findings of the thesis and presents a proposal for the methodology of studying medieval psychological concepts with directions for further research.
110

Preparation, Characterization and Testing for Photocatalytic Activities of Bi2WO6-based Materials

Qin, Hanna January 2012 (has links)
PdCl2/Bi2WO6 and Pd/Bi2WO6 composite photocatalysts were synthesized via a template free hydrothermal process and the respective photocatalytic activities were investigated by degradation of Rhodamine B. The new catalyst composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and ultraviolet visible (UV-vis) light diffuse reflectance spectra, respectively. By XRD, it was found that the loaded Pd species did not alter the crystal lattice of Bi2WO6 photocatalyst. Through the XPS spectra, it was found that the PdCl2/Bi2WO6 was successfully reduced by chemical reducing agents CH2O and N2H4, respectively, and palladium was present in the form of both metallic Pd and Pd ion spe-cies (Pd0 and Pd2+), while the Pd species in a NaBH4-reduced composite exhibited only metallic Pd species (Pd0). For the SEM images, it was observed that both classes of composites were constructed from plenty of nanoplates, which were closed packed with hierarchical structures. Furthermore, the removal efficiency of Rhodamine B was found to be influenced by parameters such as catalyst dosage, pollutant concentration and solution pH.

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