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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.
21

Molecular resists for advanced lithography - design, synthesis, characterization, and simulation

Lawson, Richard A. 04 April 2011 (has links)
Many problems exist in current photoresist designs that will limit their ability to obtain the performance required for future generations of integrated circuit devices. In order to overcome these challenges, novel resist designs are required, along with advancement in the fundamental understanding of the source of these problems. A mesoscale kinetic Monte Carlo simulation of resists was developed to probe the effects of changes in resist formulation and processing. A detailed SEM simulator was developed in order to better understand the effect of metrology on the characterization of the final resist relief image. Several important structure-property relations were developed for the prediction of glass transition temperature in molecular resists and the prediction of the solubility of molecular resists in developer. Five new families of molecular resists were developed that provide solutions to some of the limitations in current resist designs. Single component molecular resists have all of the functional groups required to act as a chemically amplified resist contained in a single molecule. This eliminates inhomogeneities in the resist and provides improved line edge roughness. Non-chemically amplified molecular resists were developed that have very good sensitivity due to the unique dissolution properties of molecular resists. Negative tone molecular resists were developed that have an excellent combination of resolution, sensitivity, and line edge roughness with better resolution than has been previously seen in negative tone resists. Control methods were also developed to improve the resolution of these types of negative tone resists even further.
22

Estudo de concretos de diferentes resist?ncias ? compress?o submetidos a altas temperaturas sem e com incorpora??o de fibras de politereftalato de etileno (PET) / Study of different resistance of concrete when applied to high temperatures no and with addition fiber polyethylene terephthalate (PET)

Silva, Janaina Salustio da 22 April 2013 (has links)
Made available in DSpace on 2014-12-17T14:48:14Z (GMT). No. of bitstreams: 1 JanainaSS_DISSERT.pdf: 4645317 bytes, checksum: 1f500f6eaf05e8ac34d38ba500240ab2 (MD5) Previous issue date: 2013-04-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The reinforced concrete structures are largely used in buildings worldwide. Upon the occurrence of fire in buildings, there is a consensus among researchers that the concrete has a high resistance to fire, due mainly to its low thermal conductivity. However, this does not mean that this material is not affected by exposure to high temperatures. Reduction of the compressive strength, modulus of elasticity, discoloration and cracking, are some of the effects caused by thermal exposure. In the case of concretes with higher resistance occurs even desplacamentos explosives, exposing the reinforcement to fire and contributing to reducing the support capacity of the structural element. Considering the above, this study aims to examine how the compressive strength and porosity of concrete are affected when subjected to high temperatures. Were evaluated concrete of different resistances, and even was the verified if addition fibers of polyethylene terephthalate (PET) in concrete can be used as an alternative to preventing spalling. The results indicated that explosive spalling affect not only high strength concrete whose values of this study ranged from 70 to 88 MPa, as well as conventional concrete of medium strength (52 MPa) and the temperature range to which the concrete begins to suffer significant changes in their resistance is between 400 ? C and 600 ? C, showing to 600 ? C a porosity up to 188% greater than the room temperature / As estruturas de concreto armado s?o largamente utilizadas nas edifica??es em todo o mundo. Quando da ocorr?ncia de inc?ndio em edifica??es, ? consenso entre os estudiosos, que o concreto apresenta uma elevada resist?ncia ao fogo, devido principalmente a sua baixa condutividade t?rmica. No entanto, isto n?o significa que esse material n?o seja afetado pela exposi??o a elevadas temperaturas. Redu??o de resist?ncia ? compress?o e no m?dulo de elasticidade, altera??o na colora??o e aparecimento de fissuras, s?o alguns dos efeitos causados pela exposi??o t?rmica. No caso de concretos com resist?ncia mais elevada, ocorre ainda desplacamentos explosivos, expondo as armaduras ao fogo, e contribuindo assim para a redu??o da capacidade suporte do elemento estrutural. Diante do exposto, o presente trabalho tem por objetivo analisar como a resist?ncia ? compress?o e a porosidade do concreto s?o afetadas quando submetido a elevadas temperaturas. Foram avaliados concretos de diferentes resist?ncias, e ainda foi verificado se a incorpora??o de fibras de politereftalato de etileno (PET), em matriz de concreto, pode ser usada como alternativa a preven??o do lascamento. Os resultados indicaram que lascamentos explosivos acometem n?o somente os concretos de alta resist?ncia, cujos valores desta pesquisa variaram de 70 a 88 MPa, como tamb?m o concreto convencional de m?dia resist?ncia (52 MPa), e que a faixa de temperatura para o qual o concreto come?a a sofrer altera??es expressivas em sua resist?ncia fica entre 400 ?C e 600 ?C, apresentando aos 600 ?C uma porosidade at? 188% maior que a apresentada a temperatura ambiente
23

Frequ?ncia e significado cl?nico da express?o da glicoprote?na P e da prote?na relacionada a resist?ncia a m?ltiplas drogas na leucemia miel?ide aguda

Cunha, Andr?a Luciana Ara?jo da 30 August 2013 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-04T19:56:36Z No. of bitstreams: 1 AndreaLucianaAraujoDaCunha_TESE.pdf: 62271689 bytes, checksum: f3e505d6758068c74606405cf05b2b9c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-05T19:52:34Z (GMT) No. of bitstreams: 1 AndreaLucianaAraujoDaCunha_TESE.pdf: 62271689 bytes, checksum: f3e505d6758068c74606405cf05b2b9c (MD5) / Made available in DSpace on 2016-01-05T19:52:34Z (GMT). No. of bitstreams: 1 AndreaLucianaAraujoDaCunha_TESE.pdf: 62271689 bytes, checksum: f3e505d6758068c74606405cf05b2b9c (MD5) Previous issue date: 2013-08-30 / Despite the advances in the cure rate for acute myeloid leukemia, a considerable number of patients die from their disease due to the occurrence of multidrug resistance (MDR). Overexpression of the transporter proteins P-glycoprotein (Pgp) and multidrug resistance-associated protein (MRP) confer resistance to the treatment these leukemias. OBJECTIVE: To analyze the expression of the Gpp and MRP1 in patients with AML by flow cytometry (FC) and to determine the correlation between expression and demographic and also clinical and laboratorial variables. METHODS: Bone marrow and peripheral blood samples from 346 patients with a diagnosis of AML were assessed for the expression of Pgp and MRP1 by FC. RESULTS: The expression of Pgp and MRP1 was found in 111 (32.1%) and 133 (38.4%) patients, respectively, with greater prevalence in older patients and lower in adolescents, observing also a high incidence in patients with refractory disease, recurrence and secondary in comparison with the cases of de novo AML. Regarding the laboratory findings, we observed a higher correlation statistically significant between the expression of Pgp and MRP1 in AML CD34+ and FAB AML M7, M5A and M2 and lower the M3 subtype, not observed statistically significant correlation between the phenotype MDR and other laboratory data such with hemoglobin, leukocyte count, platelet count, aberrant expression of lymphoid antigens (CD2, CD7 and CD19) and clinical signs related to the disease. CONCLUSIONS: The results showed that the detection of MDR phenotype by flow cytometry can be a molecular marker for prognosis independent patients diagnosed with AML.
24

Influ?ncia da forma??o de pozolanas com adi??o de metacaulim em concreto de alta resist?ncia

Soares, Faisy Paulino Pereira 15 March 2013 (has links)
Made available in DSpace on 2014-12-17T14:58:21Z (GMT). No. of bitstreams: 1 FaisyPPS_DISSERT_Capa_ate _pag30.pdf: 3190627 bytes, checksum: 6b8c39ddf6fc3949b555ea3b2beef8a3 (MD5) Previous issue date: 2013-03-15 / The need to build durable structures and resistant to harsh environments enabled the development of high strength concrete, these activities generate a high cement consumption, which implies factor in CO2 emissions. Often the desired strength is not achieved using only the cement composition. This study aims to evaluate the influence of pozzolans with the addition of metakaolin on the physical mechanics of high strength concrete comparing them with the standard formulation. Assays were performed to characterize the aggregates according to NBR 7211, evaluation of cement and coarse aggregate through the trials of petrography (NBR 15577-3/08) and alkali-aggregate reaction (NBR 15577-05/08). Specimens were fabricated according to NBR 5738-1/04 with additions of 0%, 4%, 6%, 8% and 10% of metakaolin for cement mortars CP V in the formulations. For evaluation of the concrete hardened in fresh state and scattering assays were performed and compressive strength in accordance with the NBR 7223/1992 and NBR 5739-8/94 respectively. The results of the characterization of aggregates showed good characteristics regarding size analysis and petrography, as well as potentially innocuous as the alkali-aggregate reaction. As to the test of resistance to compression, all the formulations with the addition of metakaolin showed higher value at 28 days of disruption compared with the standard formulation. These results present an alternative to reduce CO2 emissions, and improvements in the quality and durability of concrete, because the fine particle size of metakaolin provides an optimal compression of the mass directly influencing the strength and rheology of the dough / A necessidade de construir estruturas dur?veis e resistentes a ambientes agressivos proporcionou o desenvolvimento do concreto de alta resist?ncia, tais atividades geram um alto consumo de cimento, fator que implica na emiss?o CO2. Muitas vezes a resist?ncia desejada n?o ? atingida utilizando apenas o cimento na composi??o. Este trabalho tem como objetivo avaliar a influ?ncia das pozolanas com a adi??o de metacaulim nas caracter?sticas f?sico mec?nicas do concreto de alta resist?ncia comparando-as com a formula??o padr?o. Foram realizados ensaios de caracteriza??o dos agregados de acordo com a norma NBR 7211, avalia??o do cimento e agregado gra?do atrav?s dos ensaios de petrografia (NBR 15577 - 3/08) e rea??o alcali-agregado (NBR 15577-05/08). Foram confeccionados corpos de prova de acordo com a norma NBR 5738-1/04 com adi??es de 0%, 4%, 6%, 8% e 10% de metacaulim em substitui??o ao cimento CP V nas formula??es. Para avalia??o do concreto no estado fresco e endurecido foram realizados ensaios de espalhamento e resist?ncia ? compress?o de acordo com as normas NBR 7223/1992 e NBR 5739-8/94 respectivamente. Os resultados da caracteriza??o dos agregados apresentaram boas caracter?sticas quanto ? an?lise granulom?trica e petrografia, bem como potencialmente in?cuos quanto ? rea??o alcali-agregado. Quanto ao ensaio de resist?ncia ? compress?o, todas as formula??es com adi??o de metacaulim apresentaram valor superior aos 28 dias de ruptura quando comparadas com a formula??o padr?o. Estes resultados apresentam uma alternativa de redu??o da emiss?o de CO2, al?m de melhorias na qualidade e durabilidade do concreto, pois a fina granulometria do metacaulim proporciona uma ?tima compacta??o da massa influenciando diretamente na resist?ncia mec?nica e reologia da massa
25

Estudo de Litografia por Feixe de Elétrons para a Produção de Padrões Sobre Substratos de Eletroestruturas / Study of electron beam lithografhy for patterns production on semiconductor heterostructrucres substrata.

Marcelo de Assumpcao Pereira da Silva 17 December 1996 (has links)
Este trabalho trata do estudo das condições para a produção de padrões em escala nano e micrométricas, utilizando o processo de litografia eletrônica. A parte inicial refere-se ao estudo do elétron-resiste de PMMA incluindo a preparação da solução, o recobrimento do substrato e a secagem. Em seguida, são apresentados estudos sobre o funcionamento do sistema de litografia por feixe de elétrons em detalhe. São tratados problemas com o resiste, o substrato e a interação com a amostra. São apresentados os aspectos mais importantes dos substratos utilizados, sendo dado um enfoque a heteroestruturas semicondutoras com gás de elétrons bidimensionais. As condições para revelação do resiste e das etapas de processamento para que seja feita a replicação para o substrato do padrão gerado no resiste são também abordadas. Diversos estudos foram realizados para mostrar a influência de alguns efeitos comuns na litografia como a influência da espessura do filme de resiste e os efeitos de proximidade. Também trata da produção de padrões sobre substratos diversos como GaAs, VIDRO, ALUMINA e PRATA. A última etapa estuda a utilização de um resiste híbrido PMMA-Sílica como um método de conformação cerâmica. Finalmente é apresentado um estudo relativo a produção de diversos padrões diferentes sobre heteroestruturas semicondutoras de AlGaAs/GaAs. / The work describe the conditions for pattern production at nano and micrometric scale using the electronic lithographic process. In the first part many types of lithographic technics are compared and the aim why the electron beam lithographic nanostructured production was chosen. Detailed results about operation with the lithographic system and some problems related to electron resist, substrate and interaction between electron beam and sample are presented. The most important substrate aspects are shown. The two dimensional electron gas (2DEG) semiconductors heterostrutures and the M B E process to grow samples are discussed too. The conditions to develop electron resist and steps for pattern transfer over the substrate are discussed. Many experimental studies were realized to show the influence and some effects, common to the lithographic process, such as electron resist thickness and the proximity effect. A production of pattern on some kind of substrate like GaAs, Glass, Aluminum, Silver can also be observed. In the last part of this work some discussion about utilisation of hybrid electron resist composite PMMA-Silica was done, as well as very important technics for ceramic conformation. Finally, the main goal of this work is presented: the production of different nanostructure samples using AlGaAs/GaAs substrates.
26

Vysoce legované litiny Ni-resist a jejich vlastnosti / High-alloyed cast irons Ni-resist and treir properties

Matulová, Anna January 2019 (has links)
This master’s thesis deals with high-alloyed Ni-Resist cast irons and their properties. The theoretical part describes their chemical composition and individual elements from which are these cast irons composed, their characteristic properties and examples of use in practice. Furthermore, the work focuses on the wear of materials, especially on abrasive wear, because Ni-Resist casts iron exhibit a number of specific properties, such as corrosion resistance, refractoriness and heat resistance and also abrasion resistance, on which is this thesis focused. Attention is also paid to other abrasion resistant materials, because specimens from different materials are compared in the practical part in order to find a more suitable material for the production of plate castings into the shakeouts.
27

身體的規訓、儀態化與抵抗- 一個幼兒園班級的民族誌研究 / The Study of Discipline, Hexis and Resistance in Body: An Ethnographic method in One Kindergarten.

陳述綸 Unknown Date (has links)
身體是一個媒介,使整個社會文化藉由身體的接觸刻印到身體裡,並透過身 體再體現文化。幼兒亦同,但相較於其他年齡層的個體,幼兒的身體更容易受成人期待或學校規範形塑。例如幼兒的扮家家酒遊戲、排隊、睡覺、吃飯等,藉由與自身以外的人、事、物接觸,有意或無意地學習社會文化。本研究旨趣於幼兒的身體如何被學校裡各種規訓機制所改造,進而看見幼兒在儀態化身體所體現的文化意識形態。因此將研究焦點關注在三個焦點,分別為(一)幼兒園課程的身體規訓;與(二)儀態化身體所體現的文化意識形態;(三)幼兒的身體如何抵抗與挑戰大人的規則。藉由一個幼兒園班級的民族誌研究,記錄幼兒園的生活的四面向:靜態教學(團討、角落、課程)、動態教學(排隊、運動)、用餐、睡覺。 本研究以Foucault 的觀點,從上述四個面向整理幼兒園課程對幼兒身體的 規訓手段,並配合Bourdieu 的分析歸納幼兒的身上所體現的四種儀態化身體(團結、受命、被管控、僵固),以瞭解規訓的策略在幼兒身上所體現的樣貌。此外,本研究也發現幼兒身體所出現四種型態身體的抵抗(挑釁、隱蔽、愉悅、溢出框架)。藉著被策略控制與抵抗之間來呈現幼兒園中教師與幼兒互動的立體樣貌。 / This is a research about early childhood education, culture and everyday lives in the kindergarten. The main points in this study is the body plays as a mediation with social culture and ideology. Social culture manifested through the body. The children’s bodies learn social culture by imitating what their observation, complying with rules in the kindergarten, etc. Researcher gets in one kindergarten in Taiwan with an ethnographic method, and pays attention to how children’s bodies were disciplined and shaped. Thus, this research focuses on three questions: 1. What are disciplinary strategies in the kindergarten? 2. What kinds of cultural values reveal through the children’s hexis bodies? 3. How children's bodies challenge and resist adult`s rules? According to these three questions, this study recorded four aspects of everyday life in kindergarten from curriculum, sleeping, table manners and queuing. The role of researcher is to fieldnotes and to analyze these data, In order to know how school disciplines children’s body. The research field is one kindergarten in Yonghe District, New Taipei,City,Taiwan. There are thirty children in this kindergarten (twenty-nine children are five years old and just one child is three years old) and two teachers, Ms. Ann and Mrs. De. This is a typical public kindergarten in Taiwan, and the curriculum model adopts Project Approach. The researcher analyzes observations with the theoretical framework about the body and society. To examine discipline curriculum in kindergarten from Foucauldian perspective and to see cultural values reflected in the children`s bodies in Bourdieuan perspective. The findings of research are as follows: 1. Teachers use four oriented (dynamic teaching, static teaching,eating and sleeping) strategies to discipline children in kindergarden. 2. Children's bodies was molded into four kinds of hexis bodies(mutually beneficial, inflexible, ordered and managed). 3. Children also resist the rules of adults by four kinds of resistance of the body (pleasure, hidden, provocation and overflow). The everyday lives in kindergarten is multiple meanings constructed by teachers and students. Thus, bodies carry with multiple meanings with discipline, hexis and resistance.
28

Nanofabrication Using Electron Beam Lithography: Novel Resist and Applications

Abbas, Arwa 12 August 2013 (has links)
This thesis addresses nanostructure fabrication techniques based on electron beam lithography, which is the most widely employed nanofabrication techniques for R&D and for the prototyping or production of photo-mask or imprint mold. The focus is on the study of novel resist and development process, as well as pattern transfer procedure after lithography. Specifically, this thesis investigates the following topics that are related to either electron beam resists, their development, or pattern transfer process after electron beam lithography: (1) The dry thermal development (contrary to conventional solvent development) of negative electron beam resists polystyrene (PS) to achieve reasonably high contrast and resolution. (2) The solvent development for polycarbonate electron beam resist, which is more desirable than the usual hot aqueous solution of NaOH developer, to achieve a low contrast that is ideal for grayscale lithography. (3) The fabrication of metal nanostructure by electron beam lithography and dry liftoff (contrary to the conventional liftoff using a strong solvent or aqueous solution), to achieved down to ~50 nm resolution. (4) The study a novel electron beam resist poly(sodium 4-styrenesulfonate) (sodium PSS) that is water soluble and water developable, to fabricate the feature size down to ~ 40 nm. And finally, (5) The fabrication of gold nanostructure on a thin membrane, which will be used as an object for novel x-ray imaging, where we developed the fabrication process for silicon nitride membrane, electroplating of gold, and pattern transfer after electron beam lithography using single layer resist and tri-layer resist stack.
29

Slow design in Chinese Su Xiu embroidery for apparel: applying silk, cotton, and wool flosses to silk and cotton fabrics with physical resist dyeing techniques using natural dye

Sun, Lushan January 1900 (has links)
Master of Science / Department of Apparel, Textiles, and Interior Design / Sherry J. Haar / This study was based on the concept of slow design, proposed after the slow food movement. The idea of slowing down production processes and increasing product quality and value suggests an antidote to the fast cycle of the fashion industry. Slow design supports two principals, inheriting tradition and maintaining eco-efficiency, which guided this project. Inheriting tradition is an expression that explores ways to sustain lost art and traditional heritage in our daily lives, as well as develop products that establish personal meaning for the consumer. Maintaining eco-efficiency of product production involves utilization of eco-friendly materials and sustainable approaches to aid in developing a healthier and cleaner ecosystem. The overall goal of this design research was to celebrate and sustain the spiritual and material civilization of the Chinese culture by creating a modern artistic interpretation of Chinese traditional arts using an environmentally conscious approach that was applicable to apparel design. This research created modern surface design on a group of garments from traditional Chinese Su Xiu embroidery, physical resist techniques, and natural dyes. This practice-based research utilized the paradigm of naturalistic inquiry to guide the stages of this project. A progressive design process was adopted in response to the unexpected events in the final artifact development. In the design exploration stage, a color library was created to provide the color story for the final artifacts. Basic Su Xiu embroidery stitches and traditional physical resist techniques were sampled with selected flosses and fabrics. Various samples were critiqued and analyzed to develop three unique techniques from characteristics of traditional Chinese Su Xiu embroidery, physical resist techniques (Zha Jiao, Feng Jiao, pole- wrapping, and Jia Xie), using natural dyeing techniques with woad and madder. Natural dye findings included using madder to overdye woad to adjust or reverse colors and that woad overpowered the effects of iron and acid premordants. The outcome resulted in a water-inspired series of three garments that showed evidence of simplified traditional techniques with reduced production time, energy, and dyeing material while encompassing elements of traditional art using a modern aesthetic. The designs and process were presented in a public exposition.
30

Desenvolvimento do processo de secagem em rama na produ??o de palmilhas para cal?ados

Ceron, Luciano Peske 28 March 2008 (has links)
Made available in DSpace on 2015-04-14T13:58:26Z (GMT). No. of bitstreams: 1 401118.pdf: 5442692 bytes, checksum: 0c3e9f42f5d3973f12f6e4af2dbe4ef5 (MD5) Previous issue date: 2008-03-28 / A palmilha ? um dos componentes mais importantes da ind?stria cal?adista, sendo considerada o chassi do cal?ado, pois, ? sobre ela que o cal?ado ? montado. Este estudo do processo de secagem em Rama constitui-se uma tentativa de reduzir os custos com GLP na produ??o de palmilhas, realizado em uma ind?stria de componentes para cal?ados. Inicia com a origem e evolu??o da hist?ria do cal?ado, levando a um dos componentes atuais da fabrica??o de palmilhas, o n?o-tecido de poli?ster. Aborda-se a impregna??o de n?o-tecidos e os recursos t?cnicos do secador Rama, no processo de fabrica??o. Foi desenvolvida uma metodologia de controle da umidade em palmilha e estudo das curvas de secagem, velocidade versus umidade, para os n?o-tecidos com gramaturas de 110, 150 e 200 g/m2. Nestas curvas, foram desenvolvidos perfis t?rmicos de produ??o, sendo relevante um econ?mico, lento e de baixa temperatura, e outro avan?ado, r?pido e de alta temperatura. Utilizou-se o m?todo Simplex Modificado para corrigir pontos nestes perfis, buscando a minimiza??o e maximiza??o da velocidade no secador. As curvas de secagem foram usadas como modelos para produ??o, levando a conclus?o que o perfil t?rmico econ?mico minimiza em 19,4% o consumo de GLP, uma economia de R$ 80.588,00/ano. O perfil t?rmico avan?ado, por sua vez, encarece em 31,1% o consumo de GLP, representando um incremento de R$ 128.941,00/ano. A certifica??o das curvas foi realizada no laborat?rio credenciado do Centro Tecnol?gico do Cal?ado SENAI - Novo Hamburgo, que identificou como melhor quantitativamente o perfil t?rmico econ?mico em zonas de baixa velocidade. Este trabalho mostrou que o controle de processos ? uma alternativa eficaz para o controle dos custos.

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