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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.
71

Li Shangyin : the poetry of allusion

Yu, Teresa Yee-Wah January 1990 (has links)
A major poet of the Tang period, Li Shangyin is highly regarded yet criticized because his work is densely allusive. Dazzling and rich in meaning, it is also difficult and obscure because of its pervasive allusiveness. Chapter I reviews critical opinion of Li's use of allusion. Many traditional critics see allusion as an ornamental rhetorical device and consider Li's profuse allusiveness an idiosyncrasy to be tolerated in an esteemed poet. Chapter II studies allusion broadly and precisely as a literary concept: generally, allusion is a "connector" of texts, a link between a poet's work and his literary heritage; specifically, it is a linguistic device serving metaphorical functions. Allusion viewed as extended metaphor generates multiple meanings. An approach to reading allusion is here developed, to interpret allusive texts on literal, allegorical, and symbolic levels. The chapter concludes that it is a misconception to say that the heavy use of allusion necessarily leads to inferior poetry. Chapter III relates Li's allusions to major motifs in his work, finding that his historical and mythological allusions fall into clusters and patterns. The profusion of mythological allusions yields symbolic meanings, both in individual poems and in the larger context of his collected works. Examining Li's characteristic use of allusion, the chapter shows how it functions as a major stylistic signature and is the principal reason for the plurisignation and ambiguity in his poetry. Chapter IV interprets several typical poems by Li Shangyin in the context of the theoretical and historical framework of the foregoing chapters. It highlights some of the major functions of allusion in these poems. A positive response to the plurisignation of Li's allusive mode allows for an inclusive critical approach to diverse interpretations and discards those readings failing the standards of consistency, coherence, and completeness . Chapter V concludes that Li's presumed vice is his virtue: his allusive texture makes his work difficult but gives it a rewarding richness. His unique use of allusion is organic. Far from being a mere ornamental device, allusion is the very poetry itself. He creates his own poetic mode, the Poetry of Allusion. / Arts, Faculty of / Asian Studies, Department of / Graduate
72

A Performance Guide to Zili Li's Viola Concerto No. 1 (2010)

Chen, Fang 12 1900 (has links)
The Viola Concerto No. 1 was commissioned in 2010 by Xidi Shen, a viola professor at the Shanghai Conservatory of Music, and composed the same year by Zili Li (b. 1938), a Chinese composer and violinist. For musical, cultural, and technical reasons, this little-known Chinese viola concerto strongly aroused my interest, leading me to use it as the research subject for my doctoral dissertation and to also introduce this work to Western violists. This dissertation provides a performance guide to Zili Li's Viola Concerto No. 1. By analyzing the Mongolian music topics used in the work as well as addressing its typical Mongolian-style string performance techniques, the dissertation should provide a foundation for viola players who wish to play the work but are not familiar with this specific style. In addition, I hope that it can serve as an inspiration to other string players who are playing works based on Mongolian music.
73

NMR Study on Mn(II) Contaminants on Lithium-Ion Batteries

Zheng, Runze 11 1900 (has links)
Nickel-manganese-cobalt oxide (NMC) cathode materials have been applied in most Li-ion batteries, but there are nevertheless some concerns regarding the stability of this material. High voltage and high temperature during charging have been shown to accelerate the dissolution of NMC due to the release of more acidic components because of rapid electrolyte decomposition. Mn-contaminants (Mn2+) are hypothesized to diminish the diffusion coefficient of Li+ in the electrolyte attributed to the competitive interaction between Mn2+ ions and Li+ ions. With characterizations including 7Li and 1H pulsed field-gradient nuclear magnetic resonance (PFG-NMR) spectroscopy, we demonstrated the Mn (II)-contaminants effect on diffusion coefficient on Li+ dynamics. Under the influence of deliberate manganese salt-additive to the electrolyte, the coin cell shows a capacity fading and unstable charging behavior. The PFG-NMR measurements also validated our hypotheses, as the results showing that Mn-containment causes decrease ~15% in the diffusion coefficient on Li-self diffusion. The activation energy for lithium-ion transport over the temperature range of (273 K - 303 K), was not changed by the presence of the Mn-contaminant electrolyte, which indicates the Mn (II) does not affect the Li-ion transport mechanism. The relative test also includes comparisons with other contamination, such as iron contamination from stain-less steels spacers and copper contamination from the current collector. Additionally, the lithium self-diffusion coefficient was tested before and after charging using a full battery configuration. In electrolytes containing manganese contaminants, a more significant decrease in the diffusion coefficient was observed after charging. Ideally, operando experiments can be used to observe the impact of manganese ions on the SEI. By combining both types of experiments, a closer approximation to the actual application conditions of market-used batteries can be achieved. / Thesis / Master of Science (MSc) / The increasing maturity of lithium battery technology has also promoted the advancement of the electric vehicle manufacturing industry. As an excellent new energy material, the application and development of lithium batteries will be the main trend in the future. However, while improving battery capacity and energy density, lithium batteries also face many challenges. The entire thesis work discusses how electrolyte degradation at high temperatures and high voltages accelerates the dissolution of transition metal manganese ions in NMC materials. The dissolution of manganese ions into the electrolyte creates a competitive effect with lithium ions, thereby reducing the performance of lithium batteries. Here, NMR technology was used to measure the negative effect of manganese ions on the self-diffusion coefficient of lithium ions in the electrolyte. Additionally, a set of operando experiments conducted at different discharge rates demonstrated the changes in mossy lithium and the solid electrolyte interface during the charge and discharge phases caused by pulse discharge. This also proved that such experimental designs can track the impact of manganese ions on the solid electrolyte interface and test the dissolution behavior and impact of manganese ions under different charge and discharge rates.
74

Atuação da mutação R337H em TP53 em pacientes de Li-Fraumeni em autofagia, senescência e função mitocondrial

Hütten, Michele Oliveira January 2016 (has links)
Introdução: As síndromes de Li-Fraumeni (LFS) e Li-Fraumeni Like (LFL) são síndromes hereditárias de predisposição a câncer frequentemente associadas à mutações germinativas no gene TP53. Devido à importância de p53 e diversidade de processos celulares que ela regula, várias vias de sinalização podem ser afetadas pela doença. Nesse estudo discutimos o impacto da mutação p.R337H na proliferação, senescência, autofagia, população e funcionalidade mitocondrial. Métodos: As taxas de proliferação foram avaliadas pelo ensaio de Population Doubling. Os experimentos de senescência, autofagia, massa total e funcionalidade mitocondrial foram realizados por citometria de fluxo. Resultados: As células contendo a mutação proliferaram mais do que as células controle. Além disso, as células mutadas não ativaram autofagia sob tratamento de Rapamicina nem senescência sob tratamento de Doxorubicina ou Cisplatina e exibiram maior população mitocondrial, mas com funcionalidade inalterada após os tratamentos. Conclusão: os dados sugerem que a mutação p.R337H em TP53 afeta a indução de senescência realizada por p53 e suas funções pró-autofágicas, bem como seu controle. As células mutadas proliferam mais do que células sem mutação em TP53 e exibiram maior massa mitocondrial sem perda de funcionalidade após o tratamento com Doxorubicina. / Background: Li-Fraumeni (LFS) and Li-Fraumeni Like (LFL) syndromes are hereditary cancer predisposition syndromes frequently associated with germline mutation in TP53. Due to the importance of the protein p53 and its regulation of several important cellular processes, impairment in some pathways can be implicated. Here we discuss the impact of p.R337H TP53 mutation on proliferation, senescence, autophagy, mitochondrial population and functionality. Methods: Growth rates were assayed with Population Doubling assay. Senescence and autophagy were assessed through flow cytometry and functionality and total population of mitochondria were also analyzed through flow cytometry. Results: mutated cells proliferated more than control cells. TP53 mutated cells didn’t build up autophagy under Rapamycin treatmend nor senescence under Doxorubicin or Cisplatin treatments and showed more mitochondrial mass, but no alterations in mitochondrial functionality after Doxorubicin treatment. Conclusion:data suggests that p.R337H TP53 mutation affect senescence induction by p53 and pro-autophagic actions of p53. Mutated cells proliferate more than control cells and exhibited larger mitochondrial mass without effects in their functionality in response to Doxorubicin treatment.
75

Atuação da mutação R337H em TP53 em pacientes de Li-Fraumeni em autofagia, senescência e função mitocondrial

Hütten, Michele Oliveira January 2016 (has links)
Introdução: As síndromes de Li-Fraumeni (LFS) e Li-Fraumeni Like (LFL) são síndromes hereditárias de predisposição a câncer frequentemente associadas à mutações germinativas no gene TP53. Devido à importância de p53 e diversidade de processos celulares que ela regula, várias vias de sinalização podem ser afetadas pela doença. Nesse estudo discutimos o impacto da mutação p.R337H na proliferação, senescência, autofagia, população e funcionalidade mitocondrial. Métodos: As taxas de proliferação foram avaliadas pelo ensaio de Population Doubling. Os experimentos de senescência, autofagia, massa total e funcionalidade mitocondrial foram realizados por citometria de fluxo. Resultados: As células contendo a mutação proliferaram mais do que as células controle. Além disso, as células mutadas não ativaram autofagia sob tratamento de Rapamicina nem senescência sob tratamento de Doxorubicina ou Cisplatina e exibiram maior população mitocondrial, mas com funcionalidade inalterada após os tratamentos. Conclusão: os dados sugerem que a mutação p.R337H em TP53 afeta a indução de senescência realizada por p53 e suas funções pró-autofágicas, bem como seu controle. As células mutadas proliferam mais do que células sem mutação em TP53 e exibiram maior massa mitocondrial sem perda de funcionalidade após o tratamento com Doxorubicina. / Background: Li-Fraumeni (LFS) and Li-Fraumeni Like (LFL) syndromes are hereditary cancer predisposition syndromes frequently associated with germline mutation in TP53. Due to the importance of the protein p53 and its regulation of several important cellular processes, impairment in some pathways can be implicated. Here we discuss the impact of p.R337H TP53 mutation on proliferation, senescence, autophagy, mitochondrial population and functionality. Methods: Growth rates were assayed with Population Doubling assay. Senescence and autophagy were assessed through flow cytometry and functionality and total population of mitochondria were also analyzed through flow cytometry. Results: mutated cells proliferated more than control cells. TP53 mutated cells didn’t build up autophagy under Rapamycin treatmend nor senescence under Doxorubicin or Cisplatin treatments and showed more mitochondrial mass, but no alterations in mitochondrial functionality after Doxorubicin treatment. Conclusion:data suggests that p.R337H TP53 mutation affect senescence induction by p53 and pro-autophagic actions of p53. Mutated cells proliferate more than control cells and exhibited larger mitochondrial mass without effects in their functionality in response to Doxorubicin treatment.
76

Atuação da mutação R337H em TP53 em pacientes de Li-Fraumeni em autofagia, senescência e função mitocondrial

Hütten, Michele Oliveira January 2016 (has links)
Introdução: As síndromes de Li-Fraumeni (LFS) e Li-Fraumeni Like (LFL) são síndromes hereditárias de predisposição a câncer frequentemente associadas à mutações germinativas no gene TP53. Devido à importância de p53 e diversidade de processos celulares que ela regula, várias vias de sinalização podem ser afetadas pela doença. Nesse estudo discutimos o impacto da mutação p.R337H na proliferação, senescência, autofagia, população e funcionalidade mitocondrial. Métodos: As taxas de proliferação foram avaliadas pelo ensaio de Population Doubling. Os experimentos de senescência, autofagia, massa total e funcionalidade mitocondrial foram realizados por citometria de fluxo. Resultados: As células contendo a mutação proliferaram mais do que as células controle. Além disso, as células mutadas não ativaram autofagia sob tratamento de Rapamicina nem senescência sob tratamento de Doxorubicina ou Cisplatina e exibiram maior população mitocondrial, mas com funcionalidade inalterada após os tratamentos. Conclusão: os dados sugerem que a mutação p.R337H em TP53 afeta a indução de senescência realizada por p53 e suas funções pró-autofágicas, bem como seu controle. As células mutadas proliferam mais do que células sem mutação em TP53 e exibiram maior massa mitocondrial sem perda de funcionalidade após o tratamento com Doxorubicina. / Background: Li-Fraumeni (LFS) and Li-Fraumeni Like (LFL) syndromes are hereditary cancer predisposition syndromes frequently associated with germline mutation in TP53. Due to the importance of the protein p53 and its regulation of several important cellular processes, impairment in some pathways can be implicated. Here we discuss the impact of p.R337H TP53 mutation on proliferation, senescence, autophagy, mitochondrial population and functionality. Methods: Growth rates were assayed with Population Doubling assay. Senescence and autophagy were assessed through flow cytometry and functionality and total population of mitochondria were also analyzed through flow cytometry. Results: mutated cells proliferated more than control cells. TP53 mutated cells didn’t build up autophagy under Rapamycin treatmend nor senescence under Doxorubicin or Cisplatin treatments and showed more mitochondrial mass, but no alterations in mitochondrial functionality after Doxorubicin treatment. Conclusion:data suggests that p.R337H TP53 mutation affect senescence induction by p53 and pro-autophagic actions of p53. Mutated cells proliferate more than control cells and exhibited larger mitochondrial mass without effects in their functionality in response to Doxorubicin treatment.
77

Testování a nabíjení akumulátorových článků / Testing and charging of accumulator cells

Sršeň, Jan January 2009 (has links)
Direction of the master's thesis is design and construct electronic device for testing available accumulators. Than there are in detail subscribe some metods of charging cells and their right usage to select type of cells. Also eventually problems that can become if the choice is false. Next part contains description of principles as several type accumulator works and their loading characteristic witch are important know for choose the best testing way. The most important knowledge is detection of stop point charging when accumulators are charged and following charging can be dangerous. Because there are more methods to detect this point so in thesis are overwrite. The most important part is design of tester. That is mapped to more segments witch communicating together. Controller part of intelligent tester contains ATmega128 microcontroller so there is present a passage of program code. Last section of master's thesis describe a physical consruction and explain division for smaller parts and hole process of tester function.
78

Relaxation Analysis of Cathode Materials for Lithium-Ion Secondary Battery / リチウムイオン二次電池正極材料の緩和解析

Seo, Imsul 24 September 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(エネルギー科学) / 甲第17912号 / エネ博第284号 / 新制||エネ||59(附属図書館) / 30732 / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 八尾 健, 教授 森井 孝, 教授 佐川 尚 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DGAM
79

Matériaux de cathode et électrolytes solides en sulfures pour batteries au lithium / Cathode materials and sulfide solid electrolytes for lithium battery

Xu, Yanghai 20 November 2017 (has links)
Les batteries lithium-air et Li-S sont des techniques prometteuses pour un stockage efficace d’énergie électrochimique. Les principaux défis sont de développer un électrolyte solide à haute conductivité ionique et des cathodes efficaces. Dans ce travail, des aérogels de carbone conducteurs avec une double porosité ont été synthétisés en utilisant la méthode de sol-gel. Ils ont été utilisés comme cathode dans des batteries lithium-air. Ces cathodes peuvent fournir deux types de canaux pour le stockage de produits de décharge, facilitant la diffusion gaz-liquide et réduisant ainsi le risque de colmatage. Presque 100 cycles été obtenus avec une capacité de 0,4 mAh et une densité de courant de 0,1 mA/cm². Pour le développement d'électrolyte solide stable et conducteur, les sulfures, en particulier Li4SnS4 et son dérivé Li10SnP2S12 ont été particulièrement étudiés. Ces composés ont été synthétisés en utilisant une technique en deux étapes comprenant la mécanosynthèse et un traitement thermique à température relativement basse qui a été optimisé afin d'améliorer la conductivité ionique. La meilleure conductivité obtenue est de 8,27×10-4 S / cm à 25°C et ces électrolytes présentent une grande stabilité électrochimique sur une large gamme de voltage de 0,5 à 7V. Les couches minces ont également été déposées en utilisant la technique de pulvérisation cathodique, avec en général une conductivité ionique améliorée. La performance des batteries Li-S assemblées avec ces électrolytes massifs doit être améliorée, en particulier en améliorant la conductivité ionique de l'électrolyte. / Lithium-air and Li-S batteries are promising techniques for high power density storage. The main challenges are to develop solid electrolyte with high ionic conductivity and highly efficient catalyzed cathode. In this work, highly conductive carbon aerogels with dual-pore structure have been synthesized by using sol-gel method, and have been used as air cathode in Lithium-air batteries. This dual- pore structure can provide two types of channels for storing discharge products and for gas-liquid diffusion, thus reducing the risk of clogging. Nearly 100 cycles with a capacity of 0.4mAh at a current density of 0.1 mA cm-2 have been obtained. For developing stable and highly conductive solid electrolyte, sulfides, especially Li4SnS4 and its phosphorous derivative Li10SnP2S12 have been particularly investigated. These compounds have been synthesized by using a two-step technique including ball milling and a relatively low temperature heat treatment. The heat treatment has been carefully optimized in order to enhance the ionic conductivity. The best-obtained conductivity is 8.27×10-4 S/cm at 25°C and the electrolytes show high electrochemical stability over a wide working range of 0.5 – 7V. Thin films have also been deposited by using the sputtering technique, with generally improved ionic conductivity. The performance of the Li-S batteries assembled with these bulk electrolytes is still to be improved, particularly by improving the ionic conductivity of the electrolyte.
80

The Fabrication of Advanced Electrochemical Energy Storage Devices With the integration of Ordered Nanomaterial Electrodes

Chen, Yu-Ming 17 July 2017 (has links)
No description available.

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