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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.
11

Preparation, characterization, and activity of mono-dispersed supported catalylsts [sic]

Hicks, Tanya Temaca. January 2004 (has links) (PDF)
Thesis (M.S.)--Chemical Engineering, Georgia Institute of Technology, 2005. / Agrawal, Pradeep K., Committee Chair ; Bommarius, Andreas S., Committee Member ; Schork, F. Joseph, Committee Member. Includes bibliographical references.
12

Long-term preservation of planar cell polarity in reversed tracheal epithelium / 反転気管上皮における平面内細胞極性の長期保存

Tsuji, Takuya 23 May 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21262号 / 医博第4380号 / 新制||医||1029(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 平井 豊博, 教授 伊達 洋至, 教授 渡邊 直樹 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
13

The Production of Vacancies During Reversed Plastic Flow

Jaffrey, Donald 05 1900 (has links)
The Portevin-le Chatelier effect in a copper-3.2 at.% tin alloy has been used to investigate the rate of vacancy production during reversed plastic flow. The production rate per unit strain has been shown to be approximately half the value found for straight tensile deformation. It was inferred from this that fatigue is not a highly efficient method for producing vacancies. The relationship between the dislocation density and the tensile plastic strain for this alloy has been determined by transmission electron microscopy. It was found to obey the law, p = const. E^1.17±0.13. It was also found that during reversed plastic flow this law was no longer valid. / Thesis / Master of Science (MSc)
14

Lap splice in glass fiber reinforced polymer‐reinforced concrete rectangular columns subjected to cyclic‐reversed loads

Naqvi, Syed 27 October 2016 (has links)
This study presents the experimental results of nine full-scale lap spliced glass-fiber reinforced polymer (GFRP) reinforced concrete (RC) columns, and one additional reference steel-RC column with lap splices, under axial and cyclic-reversed loads. The test parameters included type of reinforcement, lap splice length of longitudinal reinforcement, transverse reinforcement spacing, and the effect of using steel fiber-reinforced concrete (SFRC). Test results indicated that a splice length of 60 times the diameter of the longitudinal column bar was adequate in transferring the full bond forces along the splice length and were able to maintain the lateral load carrying capacity when subjected to higher levels of axial loads and drift ratios. In addition, lap spliced GFRP-RC columns with closely spaced transverse reinforcement achieved high levels of deformability. Furthermore, the use of SFRC in columns with inadequate splice increased the peak lateral strength and the energy dissipation of the specimens. / February 2017
15

Optimizing Peptide Fractionation to Maximize Content in Cancer Proteomics

Izumi, Victoria 01 November 2018 (has links)
The purpose of the studies included in this thesis is to develop an effective an efficient method to study the proteome using separation and detection of peptides, when only a limited amount of sample, 10 micrograms of total protein or less, is available. The analysis will be applied to multiple myeloma cancer cells using ultra high-performance liquid chromatography-mass spectrometry for expression proteomics to illustrate utility. To detect low abundance peptides in a complex proteome, we use different strategies, including basic pH reversed-phase liquid chromatography (bRPLC), mass-to-charge fractionation in the mass spectrometer, and various liquid chromatography gradients to increase peptide separation to improve opportunities for detection and quantification. The different methods are optimized and compared by the number of peptides detected. Step-wise elution of bRP spin columns proved to yield more than 36,000 peptides using only 10 μg of protein. Mass-to-charge (m/z) fractionation was tested in mass analyzer Q-Exactive Plus (Thermo Scientific). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) of an unfractionated sample was analyzed 4 times at different mass ranges, each mass range width of 150 m/z, resulting from 4 spectra combined, 31,732 peptides representing 3,967 proteins. Showingcomparable results to those form high pH reversed phase fractionation spin columns 5 fractions. Establishing a benchmark where the LC-MS/MS analysis of 600 μg of 10plex TMT-labeled peptides fractionated with bRPLC into 24 fractions yielded over 74,000 peptides from 7,700 proteins, we compared those results with analysis of 10 μg of total TMT-labeled peptides fractionated by bRP spin columns into 5 fractions, which produced 14,019 peptides from 3,538 proteins. These experiments were used to relatively quantify protein expression in naïve and drug resistant multiple myeloma cells lines as an example application in cancer research.
16

Experimental studies of confinement in the EXTRAP T2 and T2R reversed field pinches

Cecconello, Marco January 2003 (has links)
The confinement properties of fusion plasmas are affected bymagnetic and electrostatic fluctuations. The determination ofthe plasma confinement properties requires the measurement ofseveral global and local quantities such as the ion andelectron temperatures, the electron and neutral densityprofiles, the radiation emissivity profiles, the ohmic inputpower and the particle and heat diffusivities. The focus ofthis thesis is the study of the plasma confinement propertiesbased on measurements of these quantities under differentexperimental conditions. The studies have been carried out on the reversed fieldpinch experiments EXTRAP T2 and T2R at the AlfvénLaboratory, Royal Institute of Technology (KTH) in Stockholm.Studies carried out in EXTRAP T2 were focused on dynamoactivity and on the effect of phase alignment and locking tothe wall of magnetic instabilities. These were observed with adedicated imaging system. The experimental studies in EXTRAPT2R were focused on the measurement of the confinementproperties of different configurations. To this aim, a set ofdiagnostics were used some of which were upgraded, such as theinterferometer, while others were newly installed, such as aneutral particle energy analyser and a bolometer array. The dynamo, which is responsible for the plasma sustainment,involves resistive magnetohydrodynamic instabilities thatenhance stochastic transport. Furthermore, the plasmaconfinement properties are in general improved in the presenceof mode rotation. The possibility of reducing the stochastictransport and thereby further improving the confinement hasbeen demonstrated in a current profile control experiment.These results indicate that long pulse operations with aresisitive shell and current profile control are indeedfeasible. KeywordsEXTRAP T2, T2R, reversed field pinch, dynamo,energy confinement time, transport, CCD, bolometer,interferometer, neutral particle energy analyser, PPCD, MonteCarlo / QC 20100524
17

Chromatographic Behavior of Peptides Containing Oxidized Methionine in Reversed-phase Chromatography: Application to Cyclolinopeptides in Flaxseed Oil and Linear Tryptic Peptides

Lao, Ying January 2014 (has links)
The thesis consists of two parts targeting the characterization of chromatographic behavior of linear tryptic and cyclic peptides containing oxidized methionine (Met) in reversed-phased chromatography. The retention order of methionine-containing peptide analogues was observed to be the same in both studies: Met oxide < Met dioxide < Met. For linear tryptic peptides, the magnitude of the retention time shift may vary dramatically: from –9 % to +0.36 % acetonitrile. Particularly, large negative retention time shifts are found mostly associated with methionine being in the hydrophobic face of an amphipathic helix. Contrary to previously reported observations, I demonstrate for the first time that methionine oxidation may increase peptide hydrophobicity, this occurs only when methionine is in the N3 position of the N-capping stabilization motif preceding an amphipathic helix. In the second study, the effect of peak splitting was observed for some Met oxide-containing cyclolinopeptides, which most likely appear due to diastereomerization.
18

InfluÃncia do Resfriamento sub-zero apÃs o Envelhecimento na FormaÃÃo de Austenita Revertida em um AÃo Maraging 350 / Influence of sub-zero cooling after the formation of austenite on Aging Reversed in a maraging steel 350

Henrique Thiago Freire de Menezes 29 September 2008 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Os aÃos maraging sÃo materiais de ultra-alta resistÃncia sendo composto principalmente por uma base quaternÃria Ni-Co-Mo-Ti que possuem excelente tenacidade aliada com alta resistÃncia mecÃnica sendo utilizadas na indÃstria bÃlica, nuclear, componentes aeronÃuticos, vasos de pressÃo atà indÃstria esportiva. Uma de suas importantes aplicaÃÃes à na utilizaÃÃo nos motores de histerese os quais necessitam de materiais com caracterÃsticas de materiais magneticamente macios e elevada resistÃncia mecÃnica. Foram realizados ensaios de microdueza para determinar propriedades mecÃnicas nas diversas condiÃÃes de tratamento de envelhecimento e meios de resfriamento. Com o objetivo de descobrir as fases presentes no material nas diversas condiÃÃes de tratamento foram realizadas ensaios por difraÃÃo de raios-X bem como analisar a macrotextura atravÃs de FDOC`s. A microtextura foi analisada atravÃs da tÃcnica de EBSD (Electron Backscatterig Diffraction) com o intuito de estudar a influÃncia da textura da austenita na martensita nas determinadas condiÃÃes de envelhecimento e meios de resfriamento. Esta dissertaÃÃo à de grande relevÃncia para o desenvolvimento de novos produtos utilizando aÃos maraging, pois determina as condiÃÃes que oferecem as propriedades mecÃnicas, bem como as fases e textura presentes no material nas condiÃÃes de tratamento requeridas. / Maraging steels are materials of ultra high strength mainly composed of a base quaternary Ni-Co-Mo-Ti which have excellent toughness combined with high mechanical strength being used in war industry, nuclear, aircraft components, pressure vessels up to the sports industry . One of its important applications is in use in hysteresis motors which require materials with characteristics of magnetically soft materials and high mechanical strength. Microdueza tests were performed to determine mechanical properties in different treatment conditions of aging and cooling media. In order to discover the phases present in the material conditions in the various treatment trials were performed by X-ray diffraction as well as analyze the macrotexture through FDOC `s. The microtexture was examined using the technique of EBSD (Electron Diffraction Backscatterig) in order to study the influence of the texture of the austenite in the martensite aging in certain conditions and means of cooling. This thesis is of great importance for the development of new products using maraging steel, because it determines the conditions that provide the mechanical properties as well as the phases and texture present in the material conditions of treatment required.
19

The Biomechanics of Reverse Shoulder Arthroplasty

Gutiérrez, Sergio 01 July 2009 (has links)
Rotator cuff deficiency with glenohumeral arthritis presents a unique challenge to the orthopaedic surgeon. Under these conditions, total shoulder replacement has yielded poor results as a result of eccentric loading of the glenoid leading to loosening and early failure. Multiple procedures have been recommended to resolve this problem including total shoulder arthroplasty, shoulder arthrodesis, and hemiarthroplasty. Hemiarthroplasty, the current standard of care for this condition, offers only limited goals for functional improvement and only a modest improvement in pain. Recently, there has been renewed interest in reverse shoulder arthroplasty. The main concept behind the reverse shoulder implant is the stabilization of the joint by replacing the head of the arm with a socket and placing a ball on the shoulder side. This "reverse" configuration creates a fixed fulcrum through which the deltoid can act more efficiently at raising the arm and thus increasing range of motion and returning the patient to a more normal level of function. This dissertation attempts to fill in some of the gaps in reverse basic science with six published studies. The important results found in these studies were: Implantation of the glenosphere with an inferior tilt reduces the incidence of mechanical failure of the baseplate. A positive linear correlation is present between abduction range of motion (ROM) and center of rotation offset (CORO). When comparing several factors affecting ROM and scapular impingement, CORO had the largest effect on ROM, followed by glenosphere position. Neck-shaft angle had the largest effect on inferior scapular impingement, followed by glenosphere position. Stability is determined primarily by increasing joint compressive forces and, to a lesser extent, by increasing humerosocket depth. There are three distinct classes of arc of motion relative to the articular constraint: I - arc of motion decreased with increased constraint, II - arc of motion with a complex relationship to constraint, and III - arc of motion increased with increased constraint. The information presented in this dissertation may be useful to the orthopaedic surgeon when deciding on an appropriate reverse implant and improving surgical technique, as well as aiding engineers in improving reverse implant design.
20

Macrolide and Ketolide Antibiotic Separation by Reversed Phase High Performance Liquid Chromatography

Lingerfelt, Brian, Champney, W. Scott 01 July 1999 (has links)
Twenty different macrolide and ketolide antibiotics were analyzed by reversed phase high performance liquid chromatography on an ODS-2 cartridge column. Each of these compounds was uniquely separated and purified by varying the flow rate. Retention times of the individual drugs were proportional to the flow rate of the mobile phase. Recovery of antimicrobial activity for most of the drugs was greater than 90% based on a microbiological assay of material recovered from the column. Retention times were related to structural differences between these antimicrobial agents.

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