Dissertations / Theses on the topic 'Separation science'
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Hoettges, Kai F. "Miniaturisation in separation science : liquid-liquid separation on a chip." Thesis, University of Surrey, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252454.
Full textClark, Jonathan Edward. "Unique Applications of Nanomaterials in Separation Science." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1282335513.
Full textNordborg, Anna. "Synthesis and modifications of materials for separation science." Doctoral thesis, Umeå : Department of Chemistry, Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1572.
Full textZewe, Joseph William. "The Development of Novel Nanomaterials for Separation Science." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345485921.
Full textHoule, Michael E. "Weak separation of sets." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74229.
Full textMuch attention has been given to this problem, for many classes of objects and separating surfaces. However, very few satisfactory alternatives exist when the objects are not separable by any of the surfaces of the chosen class. In this thesis, a new combinatorial measure of separability is proposed, based on the largest subset of the objects in $R cup G$ that may be separated using surfaces drawn from a certain class. The combinatorial and algorithmic questions arising from this weak separation measure are the main focus of the thesis. The strong relationship between the separable subsets of point sets and faces of hyperplane arrangements is investigated, and a variety of algorithms are presented for finding linear and spherical separators for point sets and sets of hyperspheres.
Coughlin, Devin. "Type-Intertwined Separation Logic." Thesis, University of Colorado at Boulder, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3704668.
Full textStatic program analysis can improve programmer productivity and software reliability by definitively ruling out entire classes of programmer mistakes. For mainstream imperative languages such as C, C++, and Java, static analysis about the heap---memory that is dynamically allocated at run time---is particularly challenging because heap memory acts as global, mutable state. This dissertation describes how to soundly combine two static analyses that each take vastly different approaches to reasoning about the heap: type systems and separation logic. Traditional type systems take an alias-agnostic, global view of the heap that affords both fast verification and light-weight annotation of invariants holding over the entire program. Separation logic, in contrast, provides an alias-aware, local view of the heap in which invariants can vary at each program point. In this work, I show how type systems and separation logic can be safely and efficiently combined. The result is type-intertwined separation logic, an analysis that applies traditional type-based reasoning to some regions of the program and separation logic to others---converting between analysis representations at region boundaries---and summarizes some portions of the heap with coarse type invariants and others with precise separation logic invariants. The key challenge that this dissertation addresses is the communication and preservation of heap invariants between analyses. I tackle this challenge with two core contributions. The first is type-consistent summarization and materialization, which enables type-intertwined separation logic to both leverage and selectively violate the global type invariant. This mechanism allows the analysis to efficiently and precisely verify invariants that hold almost everywhere. Second, I describe gated separating conjunction, a non-commutative strengthening of standard separating conjunction that expresses local dis-pointing relationships between sub-heaps. Gated separation enables local heap reasoning by permitting the separation logic to frame out portions of memory and prevent the type system from interfering with its contents---an operation that would be unsound in type-intertwined analysis with only standard separating conjunction. With these two contributions, type-intertwined separation logic combines the benefits of both type-like global reasoning and separation-logic-style local reasoning in a single analysis.
Li, Yipeng. "Monaural Musical Sound Separation." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1211994188.
Full textSagar, Ambuj Daya. "Materials separation by dielectrophoresis." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14215.
Full textNewsome, Toni Elwell. "Development of Electrospun Nanomaterials and Their Applications in Separation Science." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1394798760.
Full textBeilke, Michael C. "The Development of Nanomaterials and "Green" Methods for Separation Science." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1448475540.
Full textEmmott, John David. "Chromatographic separation of metals." Thesis, University of Central Lancashire, 2016. http://clok.uclan.ac.uk/16599/.
Full textLong, Byron L. "Validity in a variant of separation logic." [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3378369.
Full textTitle from PDF t.p. (viewed on Jul 9, 2010). Source: Dissertation Abstracts International, Volume: 70-10, Section: B, page: 6348. Adviser: Daniel Leivant.
Zhou, Yi. "Membrane-Based Gas Separation For Carbon Capture." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595254659184073.
Full textPaull, Brett. "Advancing the separation sciences through the delivery of new materials, technology and methodology." Thesis, University of Plymouth, 2013. http://hdl.handle.net/10026.1/1600.
Full textChiu, William. "Processing of Supported Silica Membranes for Gas Separation." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1349815421.
Full textRatsameepakai, Waraporn. "Application of separation science and mass spectrometry to the analysis of fuels." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/392927/.
Full textYunus, Md Nurul Amziah. "Continuous dielectrophoretic separation of colloidal particles." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/79370/.
Full textHan, Yushen. "Score-informed musical source separation and reconstruction." Thesis, Indiana University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3609061.
Full textA systematic approach to retrieve individual parts in a monaural music recording with its score is introduced. We are interested in isolating the accompaniment part by removing the solo part from a recording of concerto music in which a solo instrument is accompanied by an orchestra. We require the music audio, the score, and optionally a sample library of individual notes played in isolation. Our approach is based on explicit knowledge of the musical audio at the semantic level (notes or chords) from an audio-score alignment. Such knowledge allows the spectrogram energy to be decomposed into note-based models that could be trained with the sample library. Our approach can be divided into: (1) "masking" to estimate a solo mask to remove the solo and (2) "reconstruction" to impute the missing harmonics of the orchestra notes that have been inevitably damaged in masking.
In "masking," we estimate a 2-dimensional binary mask to classify each time-frequency cell of the short-time Fourier Transform (STFT) spectrogram as either solo or accompaniment in STFT domain. We mainly employ an Expectation Maximization (EM) algorithm to decompose spectrogram magnitude into note-based models. In this process of "erasing" the soloist’s contribution to the mixture by applying the mask, the remaining orchestra is degraded. In "reconstruction," we propose a novel technique to repair such degradation. We use a state-space model for each note partial which is represented by a slowing-changing amplitude envelope and an "unwrapped" phase sequence. Such amplitude-phase representation can be computed by Kalman smoothing. It allows us to "transpose" intact partials of the orchestra part onto the degraded time-frequency region. Objective metrics and subjective listening are used on real and synthesized musical audio data for evaluation and parameter optimization.
Sims, Elodie-Jane. "Pointer analysis and separation logic." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/506.
Full textWang, Peidong. "Robust Automatic Speech Recognition By Integrating Speech Separation." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1619099401042668.
Full textPatel, Krina. "Analysis of internal diesel injector deposit formation by separation science and mass spectrometry." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/411867/.
Full textMaiko, Khumo Gwendoline. "Multidimensional separation of complex polymers according to microstructure." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86227.
Full textENGLISH ABSTRACT: Complex polymer systems have multiple distributions with regard to molecular parameters such as molar mass, functionality, chemical composition, molecular architecture and microstructure. These distributions affect the properties of the polymers making it necessary to develop separation methods to be able to correlate structure to property. A single onedimensional chromatographic method is usually not sufficient to separate these complex polymers with respect to all the distributions. Hence, multidimensional liquid chromatography is necessary for the complete analysis of complex polymers using two or more chromatographic techniques before detection. In this work, two novel liquid chromatographic methods were developed to separate complex polymers according to microstructure. Comprehensive two-dimensional liquid chromatography (LC x LC) was carried out to observe the correlation between microstructure and molar mass. The separation according to microstructure was coupled to NMR (LC-NMR) to observe, identify and quantify the different microstructural components during chromatographic elution. The first chromatographic method separated hydrogenated and deuterated polystyrene homopolymers with respect to the isotope effect. For the LC x LC experiments, liquid chromatography at critical conditions (LCCC) was employed as the first dimension separating according to the isotope effect and size exclusion chromatography (SEC) as the second dimension separating according to molar mass. The LC x LC results of the blends showed that there was an improvement in isotopic separation with an increase in molar mass. The LCNMR coupling using both 1H and 2H NMR detection allowed for the identification of low molar mass blend components which were not sufficiently separated by liquid chromatography. The second chromatographic method separated stereoregular poly(methyl methacrylate)s (PMMAs) with respect to tacticity. The LC x LC experiments of stereoregular PMMAs utilised solvent gradient liquid chromatography as the first dimension to separate according to tacticity and size exclusion chromatography (SEC) as the second dimension to separate according to molar mass. The LC x LC results showed a change in the triad composition with elution of the stereoregular PMMAs with a slight influence of molar mass. The LC-NMR coupling allowed the observation of the triad composition during chromatographic elution.
AFRIKAANSE OPSOMMING: Komplekse polimeriese sisteme het meervoudige verspreidings ten opsigte van molekulêre parameters, soos byvoorbeeld, molêre massa, funksionaliteit, chemiese samestelling, molekulêre argitektuur en mikrostruktuur. Hierdie verspreidings beïnvloed die eienskappe van die polimere en dus is dit nodig om skeidingsmetodes te ontwikkel ten einde polimeerstruktuur met polimeereienskappe te kan korreleer. ‘n Enkele een-dimensionele chromatografiese metode is gewoonlik nie voldoende om hierdie komplekse polimere te skei met betrekking tot al die verspreidings nie. Multidimensionele vloeistofchromatografie, met die insluiting van twee of meer chromatografiese tegnieke, is dus nodig om polimere te skei voor waarneming kan plaasvind. Twee nuwe chromatografiese metodes is ontwikkel om komplekse polimere volgens mikrostruktuur te skei. Twee-dimensionele vloeistofchromatografie (LC x LC) is uitgevoer ten einde die korrelasie tussen mikrostruktuur en molêre massa te ondersoek. Daarna is die skeiding wat op mikrostruktuur gebasseer is, gekoppel aan KMR (LC-KMR) om die verskillende mikrostrukturele komponente gedurende chromatografiese eluering waar te neem, te identifiseer en te kwantifiseer. Die eerste chromatografiese metode het die gehidrogeneerde en gedeutereerde polistireen geskei met betrekking tot die isotoopeffek. Hier het die LC x LC skeiding bestaan uit vloeistofchromatografie onder kritiese kondisies (LCCC) as die eerste dimensie, wat skeiding bewerkstellig het gebasseer op die isotoopeffek, en grootte-uitsluitingschromatografie (SEC) as die tweede dimensie, wat skeiding bewerkstellig het gebasseer op die molêre massa. Die LC x LC resultate van die vermengings het ‘n verbetering in isotopiese skeiding met ‘n toename in molêre massa getoon. Deur gebruik te maak van die LC-KMR koppeling, waar beide 1H en 2H KMR waarneming gebruik is, was dit moontlik om die lae-molêre-massakomponente van vermengings wat nie volledig d.m.v. LC geskei kon word nie, te identifiseer. Die tweede chromatografiese metode het stereoreëlmatige polimetielmetakrilate (PMMAs) m.b.t. taktisiteit geskei. Die LC x LC skeiding van stereoreëlmatige PMMAs het bestaan uit oplosmiddel -gradiënt-LC as eerste dimensie om volgens taktisiteit te skei, en SEC as tweede dimensie om volgens molêre massa te skei. Die LC x LC resultate het ‘n molêre massa afhanklikheid van stereoreëlmatige PMMAs op taktisiteit getoon. Die LC-KMR koppeling het dit moontlik gemaak om die triade-samestelling gedurende chromatografiese eluering waar te neem.
Joakim, Valberg. "Document Separation in Digital Mailrooms." Thesis, Linköpings universitet, Artificiell intelligens och integrerad datorsystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122406.
Full textBow, Hansen Chang. "Characterization of nanofilter arrays for small molecule separation." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37934.
Full textIncludes bibliographical references (p. 59-60).
Experimental studies were performed to evaluate methods of improving separation resolution and speed in microfabricated nanofilter arrays. Experiment parameters investigated include electric field strength, nanofilter geometry, and buffer concentration. DNA polymers of size 25-1000 base pairs were the subject of our study. We concluded that increasing electric field strength resulted in inferior separation for larger DNA polymers (400-1000 bp). Additionally, we quantified the improvement in resolution of smaller nanofilter pores and lower buffer concentration. A theoretical model based on Macrotransport Theory was developed to estimate average species velocity and peak dispersion.
by Hansen Chang Bow.
S.M.
Bronson, James. "An exploration of complex matrix factorization as a tool for single-channel musical source separation." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121548.
Full textDepuis l'introduction de la factorisation en matrices non-négatives (NMF) en tant qu'outil pour la séparation de sources musicales monophoniques (SC-MSS) au début du 21e siècle, son utilité et sa popularité ont augmenté de façon régulière et elle continue d'être un grand domaine d'intérêt au sein de la communauté de traitement du signal. Cependant, il est reconnu dans la littérature sur le sujet que l'hypothèse fondamentale du modèle de mélange pour la représentation spectrale de la source acoustique, à laquelle la NMF est appliquée, enfreint la véritable nature de la superposition des signaux acoustiques en ignorant la combinaison de phase entre sources superposées. Il est aussi reconnu que les procédures de type NMF pour la séparation de sources nécessitent des procédures de post-traitement additionnelles pour réintégrer l'information de phase à la représentation spectrale des sources une fois la factorisation complétée. Cette thèse explore la factorisation de matrices complexes (CMF), une variante de la NMF récemment proposée qui intègre l'information de phase des sources acoustiques dans le cadre de la factorisation de matrices. Ceci permet le développement de procédures de séparation de sources fondées sur un modèle de mixage ancré dans le domaine des spectres complexes (dans lequel le mélange de sources qui se superposent est préservée). La CMF apporte aussi l'avantage d'intégrer l'estimation de la phase des sources constituantes directement à l'algorithme de factorisation, ce qui élimine le besoin d'estimation de phase a posteriori. Trois expériences ont été réalisées afin d'étudier le comportement de la CMF comparé à la NMF lorsqu'appliqué à des mélanges simples fait à partir d'instruments acoustiques qui se superposent. La principale contribution de cette thèse est la formalisation d'une contrainte de phase, fondée sur des propriétés physiques, qui impose des liens entre ses estimations au court du temps. Nous montrons que l'algorithme de la CMF, armée de cette nouvelle contrainte de phase, donne des résultats prometteurs lorsqu'il est utilisé sur des signaux acoustiques simples dans le cadre de la SC-MSS.
Lee, Chia-Hua. "Development of biomimetic microfluidic adhesive substrates for cell separation." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/88374.
Full textCataloged from PDF version of thesis.
Includes bibliographical references.
Cell separation is important in medical, biological research, clinical therapy, diagnostics and many other areas. The conventional methods of cell sorting have limited applications due to sophisticated equipment settings, high costs, or time-intensive and labor-intensive processing steps. Inspired from natural cell sorting system-cell rolling, a novel microfluidic device design was proposed for point-of-care and point-of-use applications. It relies on interaction of cells with biomimetic adhesive substrates comprising multiple inclined, asymmetric bands of weak adhesive molecules. Such device design allows continuous sorting of cells without irreversible capture of cells. To realize such device, comprehensive studies of how cells settle onto the substrate, how cells capture by the substrate, the effect of substrate parameters on separation potential, and selection of adhesion molecules are needed to optimize device performance. In this thesis, first, how the cells settle and how they are captured by the receptors were studied using HL60 cells as a model leukocyte cell line and P-selectin as a model receptor. Settling distance of HL60 cells under different shear stresses inside microfluidic channels was identified from the study of convection velocity of cells at different position along the channel. The results show that settling distance increases with increasing shear stress. Cell capture was then quantified by characterizing how far settled HL60 cells travelled before they were captured by P-selectin molecules, defined as the attachment distance. Cumulative probabilities of attachment distance of cells at different shear stresses revealed that increasing shear stress results in exponential increase of the attachment distance of cells by receptor molecules. An empirical model was developed to predict capture probability by an inclined receptor band and the prediction value was verified by experimental data from a device. Second, a patterning method involving microcontact printing was developed to create biomimetic adhesive substrates comprising multiple inclined receptor bands of P-selectin molecules. The patterned substrates were then used to study how transport of HL60 cells can be controlled by the substrate parameters including pattern inclination angle with respect to shear flow direction, shear stress magnitude, and P-selectin incubation concentration. The effects of substrate parameters were quantified in terms of the edge tracking length, lateral displacement, and the rolling velocity. The edge inclination angle was identified as the strongest modulator of edge tracking length on a single band for captured cells. To study optimization of the device design, experimental data of cell settling, cell attachment, and edge tracking length were integrated into a model to predict device performance including device capture efficiency and total lateral displacement. General guidelines for microfluidic device design were established based on the results from the model: smaller band width, edge angle of 15-20°, and lower shear stress. Finally, to develop new specific receptor-ligand systems, M13 pVIII and pIll phage libraries were used for selecting peptides with affinity to CD4 proteins. Screened phage from pVIII library was immobilized on the gold surface and capture efficiency of CD4+ cells were characterized. The interaction between selectin phage and CD4+ cells were demonstrated to be CD4-dependent. Moreover, the selected phage from pIII library and the corresponding synthetic peptides were demonstrated to exhibit specificity to CD4 proteins. In summary, this thesis focuses on development of biomimetic adhesive substrates for microfluidic devices involving transient interactions between the cells and the receptor-patterned substrates. How cells flow and get captured by patterned biomimetic substrates inside the microfluidic channels, how substrates parameters affect cell rolling trajectories and device performance, and how to identify new receptor-ligand systems were discussed in this thesis. This study has led to realization of a microfluidic device for separating neutrophils from blood. This microfluidic system provides continuous sorting without irreversible capture of cells, and is believed to be an effective method that can potentially be used in many point-of-care applications. Keywords: microfluidics, cell separation, cell rolling, selectin, biopanning, M13
by Chia-Hua Lee.
Ph. D.
Osborne, Zoe Ann. "Nucleation kinetics of phase separation in a sodium silicate glass." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/284320.
Full textKULKARNI, AMIT S. "REACTION INDUCED PHASE-SEPARATION CONTROLLED BY MOLECULAR TOPOLOGY." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1108001435.
Full textMueller, Amy 1980. "Iterative blind separation of Gaussian data of unknown order." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/28457.
Full textIncludes bibliographical references (p. 125-126).
A method for blind separation of noisy jointly Gaussian multivariate signals X is presented, where X = AP + N, X is an observed set of vectors, A is the mixing matrix, P is the unknown signal matrix, and N is white noise. The objective is to estimate all matrices on the right-hand side when even their dimensions (the system order) are unknown. The algorithms developed are extensions of the Iterative Order and Noise (ION) estimation algorithm [10]. Improvements made within the iterative structure of ION to better estimate the order and noise yield ION'. The addition of a second-order blind identification algorithm (SOBI, [4]) subsequently yields ONA, which fully characterizes a data set by estimating the (O)rder, (N)oise, and mixing matrix (A). Metrics are developed to evaluate the performance of these algorithms, and their applicability is discussed. Optimum algorithm constants for ION' and ONA are derived, and their range of applicability is outlined. The algorithms are evaluated through application to three types of data: (1) simulated Gaussian data which spans the problem space, (2) a set of non-Gaussian factory data with 577 variables, and (3) a hyperspectral image with 224 channels. The ONA algorithm is extended to 2D (spatial) hyperspectral problems by exploiting spatial rather than time correlation. ONA produces a full characterization of the data with high signal-to-noise ratios for most unknown parameters in the Gaussian case, though the jointly Gaussian P is shown to be most difficult to retrieve. In all three cases, ONA reduces the noise in the data, identifies small sets of highly correlated variables, and unmixes latent signals. The spatial ONA identifies surface features in the hyperspectral image and retrieves sources
(cont.) significantly more independent than those retrieved by PCA. Further exploration of the applicability of these algorithms to other types of data and further algorithmic improvement is recommended.
by Amy Mueller.
M.Eng.
Zhao, Yan. "Droplet microfluidics for biomolecule separation and detection." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/379292/.
Full textPark, Edward S. 1974. "Microfabricated magnetophoretic focusing systems for the separation of submicrometer particles." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32268.
Full textIncludes bibliographical references.
Magnetic separation is an actively researched field due to its broad applicability to the mineral, chemical, and biological industries. The objective of this work was to design, fabricate, and test systems to study magnetophoresis of particles in suspension. To achieve this goal, two system concepts were developed: an Alternating Field System and a Flow System. Both systems consisted of permanent magnets and miniaturized devices (separation chips), which integrated microfluidic channels with ferromagnetic core elements. The systems produced "sawtooth" magnetic fields that were combined with a long-range magnetic field or pressure- driven flow to bring about migration, focusing and trapping of nonmagnetic particles suspended in ferrofluid. A potential application of such systems is high-resolution, size-based separation of DNA, cellular organelles, viruses, and other like-sized biological entities. The systems were designed using finite element analysis and fabricated using IC/MEMS microfabrication techniques. The fabrication process for the separation chips realized a microfluidic channel and electroplating molds in a single layer of SU-8 photoresist on a glass substrate. Nickel core elements were electroplated into the molds, and a PDMS cover substrate was attached using a novel technique involving contact bond and heat cycling. The systems were tested via experiments using optical fluorescence methods to observe the concentration profiles of polydisperse suspensions of polystyrene beads.
(cont.) Alternating Field System involved simple migration under a long-range magnetic field, focusing under a sawtooth magnetic field, and attempted separation by combining the long-range and sawtooth fields. The most significant findings of the trials were the significant effect of particle- particle interactions and high sensitivity to the core design of the chip. The Flow System trials combined a sawtooth field with flow. The trials demonstrated size-based trapping of particles, where 840 nm beads were trapped earlier along a separation channel, while 510 nm beads were trapped further along. Moreover, the location along the channel at which particles of a given size were trapped was shown to be a function of flow rate. Size-based trapping in magnetic potential wells, as well as flow rate tuning, could form the basis of a high-resolution particle separation system.
by Edward S. Park.
S.M.
Jacob, Silva Paulo H. "Curvature driven phase separation in mixed ligand coated gold nanoparticles." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35065.
Full textIncludes bibliographical references (leaves 31-33).
Monolayer-coated gold nanoparticles have been the subject of extensive studies in fields ranging from physics to medicine. The properties of these nanomaterials such as solubility and surface energy are often attributed solely to the chemical functionalities of the ligand head-groups. However, the morphology of these monomolecular layers on gold nanoparticles plays as important of a role as the surface chemistry. Intriguing phase-separation phenomena have been observed for mixed self-assembled monolayers (SAM) of octanethiol (OT) and mercaptopropionic acid (MPA) on the surface of gold nanoparticles. These ordered structures are studied here through scanning tunneling microscope (STM) images, as a function of the gold core diameter, which is a measure of the particle's curvature. The packing of OT homoligand nanoparticles is found to have a head-group spacing of 0.54 nm, which differs from that on flat gold (111) surfaces, 0.5 nm. The OT:MPA heteroligand nanoparticles are observed to phase-separate into ordered ribbon-like domains, with spacings that depend on the nanoparticle diameter. A geometric framework that includes a continuous and crystallographic description is established to best describe the observed behaviors.
by Paulo H. Jacob Silva.
S.B.
Ransom, Sara L. (Sara Louise) 1976. "Investigation of phase separation in GaInAsSb using transmission electron microscopy." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50484.
Full textRomero, Macias Cristina. "Image understanding for automatic human and machine separation." Thesis, Queen Mary, University of London, 2013. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8640.
Full textChokalingam, Kumar. "Poly (Allylamine Hydrochloride) and Poly (Acrylic Acid) Multilayers for Gas Separation." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1187019230.
Full textHan, Kun. "Supervised Speech Separation And Processing." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407865723.
Full textKringle, Amy. "Separation and Characterization of Reconstituted Skim Milk Powder Treated with Mineral Chelators." DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1556.
Full textCiucci, Sara, Yan Ge, Claudio Durán, Alessandra Palladini, Víctor Jiménez-Jiménez, Luisa María Martínez-Sánchez, Yutin Wang, et al. "Enlightening discriminative network functional modules behind Principal Component Analysis separation in differential-omic science studies." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-226961.
Full textHoffman, Elizabeth N. Barsoum M. W. "Carbide derived carbon from MAX-phases and their separation applications /." Philadelphia, Pa. : Drexel University, 2006. http://hdl.handle.net/1860/1120.
Full textHussain, Abid. "Dielectric properties and microwave assisted separation of eggshell and membrane." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=67033.
Full textGénéralement rejetées, les coquilles et membranes d'œuf représentent une importante réserve de composés bioactifs ayant une grande valeur économique et pécuniare, cette étude se concentre donc sur le problème de trower une méthode appropriée pour séparer la coquille de la membrane. Premièrement, notre étude évalua l'effet d'un traitement aux micro-ondes sur l'aise de séparation de la membrane de la coquille. Comme la réaction d'un matériel aux rayonnements électromagnétiques dépend de ses propriétés diélectriques, les propriétés diélectriques de coquilles et membranes furent donc indépendamment évaluées dans une gamme de frequencies de 200 MHz à 20GHz, en combinaison avec des températures variant de 25°C à 100°C. De plus, la possibilité d'utiliser cette technique pour détecter la dénaturation des protéines membranaires fut évaluée. En second lieu, l'efficacité du traitement aux micro-ondes à faciliter la séparation de la membrane de la coquille fut éprouvée en fonction de la réduction en énergie necessaire à cette séparation, soit l'énergie de liaison. Pour l'ensemble des traitements aux micro-ondes, trois facteurs à trois niveaux chacun furent évalués. Le traitement aux micro-ondes réduisit de façon significative l'énergie de liaison entre la membrane et la coquille. Un modèle fut développé permettant le calcul de l'énergie de liaison entre membrane et coquille, sous les divers traitements aux micro-ondes et selon les différents facteurs.
Reyes, González Noel I. (Noel Iván). "Pulsed field separation of biomolecules in a nanofluidic filter array." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37076.
Full text"February 3, 2006."
Includes bibliographical references (leaf 42).
In this work, pulsed electric fields are introduced as a means to enhance separation efficiency of biomolecules in a nanofluidic filter array channel. Separation under pulsed fields was tested using PBR322 DNA, Lambda Hind III DNA, and a sample containing three SDS denatured proteins. Pulsed fields are divided into long pulse and short pulse regimes, depending on how long the duration of the higher electric field pulse is compared to the average trapping time of a molecule in a single nanofluidic filter. It was found that under long pulse fields, the separation selectivity cannot be enhanced since the difference in velocity between two different molecules will always be a weighted average of the velocity at the high and low field levels of the pulsed field. On the other hand, application of pulsed fields in the short pulse regime yielded more promising results. After the pulse duration became comparable to the average trapping time of migrating molecules, the average velocity of molecules decreased with a reduction in the pulse duration. Certain bands within a sample were slowed down more than others by appropriately choosing the pulse duration, therefore resulting in increased selectivity and higher separation efficiency.
(cont.) For PBR322 DNA, separation resolution of up to 2.54 was obtained in under 15 minutes when the pulse duration was decreased down to 5ms. Novel experiments are proposed to achieve separation through band selective elution and bidirectional transport. A probabilistic model based on the binomial distribution is also proposed as a method to estimate the average velocity of molecules in the short pulse regime.
by Noel I. Reyes González.
M.Eng.and S.B.
Herring, Keith 1981. "Blind separation of noisy multivariate data using second-order statistics." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/30173.
Full textIncludes bibliographical references (leaves 81-83).
A second-order method for blind source separation of noisy instantaneous linear mixtures is presented and analyzed for the case where the signal order k and noise covariance GG-H are unknown. Only a data set X of dimension n > k and of sample size m is observed, where X = AP + GW. The quality of separation depends on source-observation ratio k/n, the degree of spectral diversity, and the second-order non-stationarity of the underlying sources. The algorithm estimates the Second-Order separation transform A, the signal Order, and Noise, and is therefore referred to as SOON. SOON iteratively estimates: 1) k using a scree metric, and 2) the values of AP, G, and W using the Expectation-Maximization (EM) algorithm, where W is white noise and G is diagonal. The final step estimates A and the set of k underlying sources P using a variant of the joint diagonalization method, where P has k independent unit-variance elements. Tests using simulated Auto Regressive (AR) gaussian data show that SOON improves the quality of source separation in comparison to the standard second-order separation algorithms, i.e., Second-Order Blind Identification (SOBI) [3] and Second-Order Non-Stationary (SONS) blind identification [4]. The sensitivity in performance of SONS and SOON to several algorithmic parameters is also displayed in these experiments. To reduce sensitivities in the pre-whitening step of these algorithms, a heuristic is proposed by this thesis for whitening the data set; it is shown to improve separation performance. Additionally the application of blind source separation techniques to remote sensing data is discussed.
(cont.) Analysis of remote sensing data collected by the AVIRIS multichannel visible/infrared imaging instrument shows that SOON reveals physically significant dynamics within the data not found by the traditional methods of Principal Component Analysis (PCA) and Noise Adjusted Principal Component Analysis (NAPCA).
by Keith Herring.
S.M.
Huang, Ying-zong. "Model-code separation architectures for compression based on message-passing." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97802.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 133-142) and index.
Data is compressible by presuming a priori knowledge known as a data model, and applying an appropriate encoding to produce a shorter description. The two aspects of compression data modeling and coding - however are not always conceived as distinct, nor implemented as such in compression systems, leading to difficulties of an architectural nature. For example, how would one make improvements upon a data model whose specific form has been standardized into the encoding and decoding processes? How would one design coding for new types of data such as in biology and finance, without creating a new system in each case? How would one compress data that has been encrypted when the conventional encoder requires data-in-the-clear to extract redundancy? And how would mobile acquisition devices obtain good compression with lightweight encoders? These and many other challenges can be tackled by an alternative compression architecture. This work contributes a complete "model-code separation" system architecture for compression, based on a core set of iterative message-passing algorithms over graphical models representing the modeling and coding aspects of compression. Systems following this architecture resolve the challenges posed by current systems, and stand to benefit further from future advances in the understanding of data and the algorithms that process them. In the main portion of this thesis, the lossless compression of binary sources is examined. Examples are compressed under the proposed architecture and compared against some of the best systems today and to theoretical limits. They show that the flexibility of model-code separation does not incur a performance penalty. Indeed, the compression performance of such systems is competitive with and sometimes superior to existing solutions. The architecture is further extended to diverse situations of practical interest, such as mismatched and partially known models, different data and code alphabets, and lossy compression. In the process, insights into model uncertainty and universality, data representation and alphabet translation, and model-quantizer separation and low-complexity quantizer design are revealed. In many ways, the proposed architecture is uniquely suitable for understanding and tackling these problems. Throughout, a discourse is maintained over architectural and complexity issues, with a view toward practical implementability. Of interest to system designers, issues such as rate selection, doping, and code selection are addressed, and a method similar to EXIT-chart analysis is developed for evaluating when compression is possible. Suggestions for system interfaces and algorithmic factorization are distilled, and examples showing compression with realistic data and tasks are given to complete the description of a system architecture accessible to broader adoption. Ultimately, this work develops one architecturally principled approach toward flexible, modular, and extensible compression system design, with practical benefits. More broadly, it represents the beginning of many directions for promising research at the intersection of data compression, information theory, machine learning, coding, and random algorithms.
by Ying-zong Huang.
Ph. D.
McCleese, Christopher. "Femtosecond Time-Resolved Spectroscopy Studies of Interfacial Charge Separation Processes." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case149182204612303.
Full textPark, Mansoo Ph D. Massachusetts Institute of Technology. "Design of bulk nanocrystalline tungsten alloys via nano-phase separation sintering." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98166.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 96-100).
An accelerated sintering method called 'nano-phase separation sintering' is developed, with specific applicability to nanostructured tungsten alloys. Nanocrystalline tungsten alloys containing minority additions of chromium are produced by high-energy ball milling and then consolidated. Such alloys exhibit the onset of sintering at a very low temperature around 950 °C and a very rapid rate of densification. The mechanism of this accelerated sintering is established through understanding the role of nano-scale, solid second phase precipitation during the sintering cycle, as analyzed by thermomechanical analysis, electron microscopy and x-ray diffraction. In addition, control experiments are used to establish that the accelerated sintering is apparently accomplished from the combination of two features of the powders: (i) nanocrystallinity and (ii) alloy supersaturation. In addition to accelerating sintering, the incorporation of alloying elements and second phases are also beneficial for mitigating grain growth during a thermal cycle, so nanophase separation sintering is thus naturally appropriate to the production of fine-grained bulk materials. Sintered compacts achieved through nano-phase separation sintering display 10~30 times smaller grain sizes at comparable densities than those produced by conventional accelerated sintering methods such as solid-state activated sintering and liquid phase sintering. The thermodynamic features and conditions for nano-phase separation sintering are further explored based on the binary phase diagram in order to generalize the concept to other alloy systems. After presenting a series of proposed alloy design rules, the consolidation of chromium with an addition of nickel is accelerated. Prospects of the technique for the development of full density bulk products in more complex alloy systems are also discussed.
by Mansoo Park.
Ph. D.
Kharechko, Andriy. "Linear and ellipsoidal pattern separation : theoretical aspects and experimental analysis." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/195011/.
Full textMears, Paula Faye. "Managing Access during Employee Separation using Blockchain Technology." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703324/.
Full textBock, Christopher Paul. "Particle separation through Taylor-Couette flow and dielectrophoretic trapping." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4625.
Full textID: 028916599; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.M.E.)--University of Central Florida, 2010.; Includes bibliographical references (p. 108-109).
M.S.M.E.
Masters
Department of Mechanical, Materials and Aerospace Engineering
Engineering and Computer Science
Miniature Engineering Systems
Kewley, Adam. "The synthesis and separation properties of organic cage compounds." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2010659/.
Full textMorin, Sandrine. "A combined numerical and experimental study of aerofoil separation bubbles." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/47094/.
Full text