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1
Bellosi, Giuditta. "Il Cyclic Sieving Phenomenon." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19258/.
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Questa tesi si ripropone di presentare il cyclic sieving phenomenon (CSP). Tale fenomeno si verifica nell’azione di un gruppo ciclico G su un insieme finito: esso consiste nel fatto che il numero di elementi dell’insieme fissati da ogni sottogruppo di G corrisponde alla valutazione di un polinomio a coefficienti interi in una radice primitiva dell’unità di ordine corrispondente a quello del sottogruppo considerato. Il nostro obbiettivo è quindi di studiare il CSP in determinati contesti algebrici. Nel primo capitolo richiameremo le nozioni necessarie alla definizione del CSP e ne evidenzieremo le caratteristiche fondamentali. Analizzeremo poi il CSP nel contesto dei multinsiemi, soffermandoci sull'azione del gruppo simmetrico su di essi e sull'utilizzo del polinomio gaussiano. Nel quarto capitolo ci occupiamo di studiare il fenomeno del setaccio ciclico nel contesto della Teoria della Rappresentazione, mostrando come il fenomeno possa essere visto come il cambiamento di base all’interno di un G-modulo. Attraverso alcuni risultati della Teoria della Rappresentazione, enunciamo il teorema che garantisce la presenza del CSP in una terna generica sfruttando esclusivamente l’isomorfismo tra G-moduli. Nell’ultima sezione definiremo i tensori simmetrici e li utilizzeremo per fornire un’ulteriore dimostrazione del CSP enunciato nel caso dei multinsiemi.
Nel quinto capitolo ci focalizzeremo sullo studio del fenomeno nel contesto dei gruppi generati da riflessioni complesse, sfruttando l’azione libera e semi libera dei gruppi ciclici. Definiremo due importanti algebre, l’algebra gruppo e l’algebra dei coinvarianti, necessarie per enunciare un importante teorema sul CSP che mette in relazione gli elementi precedentemente citati. Quest'ultimo, applicato ai gruppi di Coxeter, nello specifico al gruppo simmetrico, fornisce un'ulteriore dimostrazione del CSP sui multinsiemi.
2
Haynes, Nicholas. "The sieving electrostatic precipitator." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1176404052.
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Gottipati, Pranitha. "The dry sieving electrostatic precipitator." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1176320016.
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4
Gunenc, Mehmet V. "Enhanced Charging Sieving Electrostatic Precipitator." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1195594122.
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Kalivoda, Julie. "Effect of sieving methodolgy on determining particle size of ground corn, sorghum, and wheat by sieving." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32156.
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Master of ScienceDepartment of Grain Science and Industry
Charles Stark
Experiments were conducted to evaluate particle size methodology and flow-ability of fractionated corn. The first experiment compared five variations of the current approved method to determine geometric mean diameter (d[subscript]gw) and geometric standard deviation (S[subscript]gw) described by ANSI/ASAE S319.4 “Method of determining and expressing fineness of feed materials by sieving”. This method controls many variables, including the suggested sample size and the type, number, and size of sieves. However, the method allows for variations in sieving time, sieve agitator inclusion, and the use of dispersing agent. The variations were tested with three grains (corn, wheat, and sorghum). There was no method × grain (P>0.05) interaction for d[subscript]gw, so it was removed. Ten minute sieving time with sieve agitators and dispersing agent resulted in the lowest d[subscript]gw and greatest S[subscript]gw (P<0.05). The second experiment evaluated particle size analysis on ground corn using a 3-sieve method with varying sieving time (30, 60, and 90 s) with the addition of dispersing agent. The sieving time for the 3-sieve method referred to the time sieves were hand shaken side to side. Ninety seconds sieving time with dispersing agent (0.25 g) resulted in the lowest d[subscript]gw (P<0.05). The 3-sieve method was not developed to calculate the S[subscript]gw, so means and main effects were not determined. Experiment three evaluated particle size and flow-ability by grinding corn at two moisture (10 and 12%) with three screenings levels (0, 2.5, and 5%). Results suggested cleaning corn prior to grinding with a roller mill does not change particle size or flow-ability. Experiment four continued the evaluation of flow-ability with corn ground to three target particle sizes (400, 500, and 600 µm) and fractionated into fine, medium, and coarse segments. Target particle size impacted d[subscript]gw, S[subscript]gw, and bulk density (P<0.05), prior to fractionation. Based on the results of this experiment, flow-ability can be improved if fine particles (<282 µm) are removed. Results of these experiments indicated that particle size analysis should use sieve agitators, dispersing agent, and 10 or 15 min sieving time for the standard 13-sieve method and 90 s sieving time with dispersing agent for the 3-sieve method.
6
Uhlin, Joakim. "Combinatorics of Macdonald polynomials and cyclic sieving." Thesis, KTH, Matematik (Avd.), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-241919.
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In this thesis, we study the non-symmetric Macdonald polynomials E_λ (x;q,t) at t=0 from a combinatorial point of view, using the combinatorial formula found by J. Haglund, M. Haiman, and N. Loehr. Our primary focus is when λ is a partition. We summarize the known theory about this specialization and prove some new results related to this combinatorial formula. We also define the cyclic sieving phenomenon (CSP). For rectangular λ, we present an instance of cyclic sieving with E_λ (1,q,q^2,...,q^(k-1);1,0) as CSP-polynomial. We also conjecture another instance of CSP with E_λ (1,1,...,1;q,0) as CSP-polynomial. This conjecture generalizes a previously known CSP-triple. Furthermore, we prove this conjecture in the case when is λ an m×2 diagram.I denna uppsats studerar vi de icke-symmetriska Macdonaldpolynomen E_λ (x;q,t) när t=0 från en kombinatorisk synvinkel genom att använda den kombinatoriska formeln som visats av J. Haglund, M. Haiman och N. Loehr. Vårt huvudsakliga fokus är specialfallet då λ är en partition. Vi summerar teorin om denna specialisering och visar några nya resultat som är relaterade till den kombinatoriska formeln.Vi definierar även det cykliska sållningsfenomenet (CSF). För rektangulära λ visar vi en förekomst av cyklisk sållning med E_λ (1,q,q^2,...,q^(k-1);1,0) som CSF-polynom. Vi presenterar också en förmodan om ytterligare en förekomst av CSF med E_λ (1,1,...,1;q,0) som CSF-polynom. Denna förmodan generaliserar en tidigare förekomst av CSF. Vidare visar vi att denna förmodan är sann i fallet då λ är ett m×2 diagram.
7
Kuraoka, Koji. "Preparation and properties of molecular sieving membranes." Kyoto University, 2000. http://hdl.handle.net/2433/151539.
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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものであるKyoto University (京都大学)
0048
新制・論文博士
博士(工学)
乙第10506号
論工博第3543号
新制||工||1192(附属図書館)
UT51-2000-P673
(主査)教授 中條 善樹, 教授 田門 肇, 教授 平尾 一之
学位規則第4条第2項該当
8
Khan, Zahirul Hasan. "Bench- and Pilot-Testing of Sieving Electrostatic Precipitator." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1177721692.
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Clarkson, Gavin. "Extracting gold from gravity concentrates using grinding and sieving." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/56272.
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This thesis presents a novel, chemical-free method of extracting Yukon placer gold from various secondary and tertiary gravity middlings. This method exploits the differences in relative malleability rather than density. At a certain point in gravity gold processing, the middling material contains too many high density minerals to be amenable to further gold extraction through gravity separation. Yukon miners only use gravity extraction methods and low grade gold concentrates are stockpiled for later processing through tedious hand picking, which is rarely completed. An 8-inch diameter batch rod mill was field tested throughout the Yukon placer fields to demonstrate a chemical-free extraction alternative which exploits the resistance of gold to grinding and allows the separation of free gold particles from the finer grind products with sieving. Physical assays often indicated recoveries greater than 90% of the contained gold particles on the oversize portion of the screens, while losses reported to the undersize. The gold remaining in the fine and evenly classified loss material is now amenable to gravity processing. Furthermore, this paper reviews the importance of maximizing gold extraction in the modern Yukon placer environment, followed by reviews of gravity based upgrading equipment, the high malleability of gold, the justification for rod mill use over other comminution methods, and finally field testing methodology and preliminary results.Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
10
Ruthven, Douglas M. "Diffusion through porous media: ultrafiltration, membrane permeation and molecular sieving." Diffusion fundamentals 11 (2009) 13, S. 1-20, 2009. https://ul.qucosa.de/id/qucosa%3A13933.
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This paper considers permeation through microporous or nanoporous inorganic membranes under the influence of an applied pressure gradient. In general membrane permeation may be considered as a diffusive process, driven by the gradient of chemical potential (which depends on both composition and pressure). The relative importance of these two factors varies greatly for different types of system. The general features of such processes are reviewed and the diffusional behavior of selected systems is examined.
(membrane permeation, osmosis, diffusion, zeolite membrane, DDR-3, SAPO-34)
11
Telenta, Marijo. "AEROSOL CALCULATION AND PRESSURE DROP SIMULATION FOR SIEVING ELECTROSTATIC PRECIPITATORS." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1172857667.
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Nevins, Stacey. "The Analysis of Plasmid Conformers using Dynamic Size-Sieving Capillary Electrophoresis." W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539626169.
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Guo, Hong L. "Sieving of spherical particles during gel electrophoresis: A new computer simulation algorithm." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/6741.
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A new computer simulation algorithm is developed to study the behavior of a hard sphere during gel electrophoresis. The electrophoresis mobility and the diffusion coefficients are presented to show the effects of the field intensity, of the gel concentration, and of the randomness of the gel. The results indicate that previous models are not applicable for either the periodic or the random gel, and that the Einstein relation does not hold because the gel molecules affect the dynamics of the hard sphere. Moreover, the randomness of sieving gels lead to a trapping effect where the longitudinal diffusion coefficient is much larger than expected when the gel is dense and the field intensity is non-negligible. This trapping effect predicts a limit to both the field intensity and the gel concentration that one can use for the separation of particles during gel electrophoresis. Our new algorithm thus opens a door to a detailed study of the process of electrophoretic sieving with potential applications in biology and biotechnology.
14
Lazzara, Matthew J. "Effects of plasma proteins on the sieving of macromolecular tracers in the kidney." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/38443.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2003.Includes bibliographical references (leaves 191-202).
The ultrafiltration of plasma in the mammalian glomerulus is the first step in the processing of blood by the kidney. Proper functioning of this process is critical to the kidney's ability to effectively eliminate waste and retain desirable substances. The glomerular barrier has long been regarded as both a size and charge selective screen for plasma solutes. The origin of this selectivity is found in the unique three-layered structure of the glomerular capillary wall (GCW), consisting of a fenestrated endothelium, the interdigitating foot processes of the glomerular epithelium, and the shared glomerular basement membrane (GBM). The selectivity properties of the GCW have commonly been probed by measuring the sieving coefficients of a variety of tracers, both proteins and exogenous polymers, across the intact glomerular barrier and across isolated components of the GCW. It was found previously that the sieving coefficients of the tracers Ficoll and Ficoll sulfate across isolated GBM were greatly elevated when BSA was present at physiological levels (Bolton et al. 1998). It was suggested that most of this increase was the result of steric interactions between BSA and the tracers which increased tracer partitioning from the bulk into the GBM. Such an effect, if present, would have important implications for the interpretation of macromolecular sieving studies, both in vivo and in vitro. The goals of this thesis research were to model the effect of an abundant protein on the partitioning of a dissimilar tracer molecule, to incorporate that effect into models for glomerular sieving, and to test the partitioning model by measuring the effect of protein concentration on the partitioning of protein and Ficoll in agarose gels. The theoretical effects of solute size on partition coefficients in straight pores or randomly oriented fiber matrices have been investigated previously for very dilute solutions, where solute-solute interactions are negligible, and also for more concentrated solutions consisting of spherical solutes of uniform size. For concentrated solutions it has been found that steric and other repulsive interactions among solutes increase the partition coefficient above the dilute limit. To extend the results for porous or fibrous media to include concentrated mixtures of solutes with different sizes or shapes, we used an excluded volume approach. In this formulation, which describes steric interactions only, partition coefficients were computed by summing all volumes excluded to a solute molecule by virtue of its finite size, the finite size of other solutes, and the presence of fixed obstacles (pore walls or fibers). For a mixture of two spherical solutes, the addition of any second solute at finite concentration increased the partition coefficient of the first solute. That increase was sensitive to the size of the second solute; for a given volume fraction of the second solute, the smaller its radius, the larger the effect. When the total volume fraction of solutes was fixed, an increase in the amount of a second, smaller solute increased the partition coefficient of the first solute, whereas an increase in the amount of a second, larger solute had the opposite effect. Results were obtained also for oblate or prolate spheroidal solutes and for fibrous media with multiple fiber radii. For constant total fiber volume fraction, an increase in the amount of a second, smaller fiber decreased the partition coefficient of a spherical solute, whereas an increase in the amount of a second, larger fiber had the opposite effect. Overall, the theory suggests that the introduction of heterogeneity, whether as mixtures of solute sizes or mixtures of fiber sizes, may cause partition coefficients to differ markedly from those of uniform systems. Using the excluded volume partitioning model, the theory for the sieving of macromolecular tracers was extended to account for the presence of a second, abundant solute. Using that theory, we returned to the experimental data of Bolton et al. (1998) and attempted to model the effect of protein concentration on Ficoll sieving. The osmotic reduction in filtrate velocity caused by an abundant, mostly retained solute will also tend to elevate the tracer sieving coefficient. The osmotic effect alone explained only about one third of the observed increase in the sieving coefficients of Ficoll and Ficoll sulfate, whereas the effect of BSA on tracer partitioning was sufficient to account for the remainder. At physiological concentrations, predictions for tracer sieving in the presence of BSA were found to be insensitive to the assumed shape of the protein (sphere or prolate spheroid). The effect of plasma proteins on tracer partitioning is expected to influence sieving not only in isolated GBM, but also in intact glomerular capillaries in vivo. To test the predicted effects of solute concentration on the equilibrium partitioning of single macromolecules and macromolecule mixtures, measurements of the equilibrium partition coefficients of BSA and four narrow fractions of Ficoll were made in agarose. Solutions of each test macromolecule were equilibrated with a known volume of gel, final liquid concentrations measured, and partition coefficients calculated by applying a material balance. The partition coefficient of each molecule was measured under dilute conditions and under conditions where BSA was present at concentrated levels. All measurements were made for two different gel solid volume fractions (4 and 6%). As expected, the partition coefficients decreased with increasing gel solid volume fraction and with increasing molecular size. Increasing BSA concentration caused an increase in the partitioning of BSA itself and that of all four sizes of Ficoll. This effect was most significant for the largest molecules. A subset of the measurements repeated at a higher ionic strength demonstrated that electrostatic interactions were unimportant. The experimental results were compared with predictions generated from the excluded volume partitioning theory. Agarose was represented as a randomly oriented array of cylindrical fibers, BSA was modeled as a prolate spheroid, and Ficoll was treated as a sphere. Comparisons of the theoretical predictions with the experimental data produced generally good agreement, indicating that steric interactions among solute molecules and between solute molecules and gel fibers could explain the partitioning behavior.
by Matthew Jordan Lazzara.
Ph.D.
15
Armanios, Carim. "Molecular sieving, analysis and geochemistry of some pentacyclic triterpanes in sedimentary organic matter." Thesis, Curtin University, 1995. http://hdl.handle.net/20.500.11937/187.
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A liquid chromatographic technique using ultrastable-Y (US-Y) molecular sieve as the stationary phase and n-pentane as the mobile phase has been developed to fractionate and enrich pentacyclic triterpanes from petroleum. The sieve provides a shape-selective window which distinguishes between the various pentacyclic components, thus fractionating them on the basis of molecular shape differences. This sieving technique has been applied to isolate various pentacyclic triterpanes from sedimentary organic matter to enable better analysis of these biomarkers to be carried out.Biodegraded crude oils from three Australian basins were analysed to assess the geochemistry of their rearranged hopanes. Enhanced abundances of 25-norhopanes, 18(alpha)-30-norneohopane and diahopanes relative to the regular hopanes were observed in the most severely biodegraded samples. Geochemical interpretation of these results suggests that the enhanced abundances are due to the greater resistance of rearranged hopanes to biodegradation compared to regular hopanes. These studies also indicate that enhanced relative abundances of 25-norhopanes in these samples is most likely due to selective bacterial demethylation of (alpha beta)-hopane precursors.A branched and cyclic alkane fraction from a higher plant-derived crude oil was subjected to the US-Y chromatography procedure and the fractions eluted from the column were analysed using GC-MS. The compositions of the first two eluted fractions were markedly different from the initial branched and cyclic alkane mixture in that they were enriched in higher plant-derived triterpanes, such as bicadinanes, spirotriterpane and the oleananes and other, previously unreported, C(subscript)29 and C(subscript)30 triterpanes. A comparison of mass spectral data, GC retention and molecular sieve sorption characteristics of these compounds with those of known triterpanes of known molecular structure was used to suggest structures for the unknown compounds.Isolation of crude oil fractions enriched in pentacyclic alkanes using the sieving procedure enabled lower concentrations of bicadinanes to be detected than was previously possible by applying selective ion detection GC-MS to branched and cyclic alkane fractions. Application of this technique to a higher-plant derived Jurassic crude oil and two Jurassic sediments from the Eromanga Basin, Australia has revealed the presence of bicadinanes. The occurrence of the cis-cis-trans and trans-trans-trans bicadinane biomarkers that have previously only been reported from angiosperms may indicate an early evolution of flowering plant like species in this basin.The molecular sieving technique has also been used to isolate three pentacyclic triterpanes from low rank coals in order to obtain unambiguous structural identification and to determine their geochemical significance. A major hopanoid component isolated from a Victorian brown coal was characterised by single crystal X-ray diffraction and (subscript)13C NMR spectroscopy as 22R 17(alpha),21(beta)(H)-homohopane. This compound was shown to correspond to the later eluting 17(alpha),21(beta)(H)-homohopane and hence, for the first time, confirmed the common practice of assigning the higher retention time peak in gas chromatograms of (alpha beta) homohopanes as the 22R diastereomer. Heating of the isolated 22R (alpha beta)-homohopane on anthracite produced a mixture of the 22S and 22R diastereomers which implied a product-reactant relationship between the two epimers. Furthermore, a C(subscript)29 and a C(subscript)30 triterpane present in the hydrous pyrolysate of a Bremer Basin coal were also isolated using the molecular sieving procedure. 28 Nor-18(alpha)-oleanane was characterised by single crystal X-ray analysis while lupane was characterised by (subscript)13C NMR spectroscopy and by co-chromatography with an authentic standard on four different GC phase columns. The unusual occurrence of these triterpanes was attributed to the high sulphur content of the coal.Finally, laboratory isomerisation and reduction of an isomeric mixture of oleanenes was carried out to investigate the origin of oleanane (18(beta)-oleanane) and 18(alpha)-oleanane. Laboratory results indicated that oleanane was mainly derived from olean-18-ene, while 18(alpha)-oleanane was derived from 18(alpha)-olean-12-ene. Analysis of oleanene/oleanane abundances in a sedimentary sequence from Indonesia provided results consistent with laboratory evidence showing that 18(alpha)- olean-12-ene, rather than oleanane, is the main sedimentary precursor of 18(alpha)- oleanane.
16
Armanios, Carim. "Molecular sieving, analysis and geochemistry of some pentacyclic triterpanes in sedimentary organic matter." Curtin University of Technology, School of Applied Chemistry, 1995. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=11421.
Full textAbstract:
A liquid chromatographic technique using ultrastable-Y (US-Y) molecular sieve as the stationary phase and n-pentane as the mobile phase has been developed to fractionate and enrich pentacyclic triterpanes from petroleum. The sieve provides a shape-selective window which distinguishes between the various pentacyclic components, thus fractionating them on the basis of molecular shape differences. This sieving technique has been applied to isolate various pentacyclic triterpanes from sedimentary organic matter to enable better analysis of these biomarkers to be carried out.Biodegraded crude oils from three Australian basins were analysed to assess the geochemistry of their rearranged hopanes. Enhanced abundances of 25-norhopanes, 18(alpha)-30-norneohopane and diahopanes relative to the regular hopanes were observed in the most severely biodegraded samples. Geochemical interpretation of these results suggests that the enhanced abundances are due to the greater resistance of rearranged hopanes to biodegradation compared to regular hopanes. These studies also indicate that enhanced relative abundances of 25-norhopanes in these samples is most likely due to selective bacterial demethylation of (alpha beta)-hopane precursors.A branched and cyclic alkane fraction from a higher plant-derived crude oil was subjected to the US-Y chromatography procedure and the fractions eluted from the column were analysed using GC-MS. The compositions of the first two eluted fractions were markedly different from the initial branched and cyclic alkane mixture in that they were enriched in higher plant-derived triterpanes, such as bicadinanes, spirotriterpane and the oleananes and other, previously unreported, C(subscript)29 and C(subscript)30 triterpanes. A comparison of mass spectral data, GC retention and molecular sieve sorption characteristics of these compounds with those of known ++triterpanes of known molecular structure was used to suggest structures for the unknown compounds.Isolation of crude oil fractions enriched in pentacyclic alkanes using the sieving procedure enabled lower concentrations of bicadinanes to be detected than was previously possible by applying selective ion detection GC-MS to branched and cyclic alkane fractions. Application of this technique to a higher-plant derived Jurassic crude oil and two Jurassic sediments from the Eromanga Basin, Australia has revealed the presence of bicadinanes. The occurrence of the cis-cis-trans and trans-trans-trans bicadinane biomarkers that have previously only been reported from angiosperms may indicate an early evolution of flowering plant like species in this basin.The molecular sieving technique has also been used to isolate three pentacyclic triterpanes from low rank coals in order to obtain unambiguous structural identification and to determine their geochemical significance. A major hopanoid component isolated from a Victorian brown coal was characterised by single crystal X-ray diffraction and (subscript)13C NMR spectroscopy as 22R 17(alpha),21(beta)(H)-homohopane. This compound was shown to correspond to the later eluting 17(alpha),21(beta)(H)-homohopane and hence, for the first time, confirmed the common practice of assigning the higher retention time peak in gas chromatograms of (alpha beta) homohopanes as the 22R diastereomer. Heating of the isolated 22R (alpha beta)-homohopane on anthracite produced a mixture of the 22S and 22R diastereomers which implied a product-reactant relationship between the two epimers. Furthermore, a C(subscript)29 and a C(subscript)30 triterpane present in the hydrous pyrolysate of a Bremer Basin coal were also isolated using the molecular sieving procedure. 28 Nor-18(alpha)-oleanane was characterised by single crystal X-ray analysis while lupane was ++
characterised by (subscript)13C NMR spectroscopy and by co-chromatography with an authentic standard on four different GC phase columns. The unusual occurrence of these triterpanes was attributed to the high sulphur content of the coal.Finally, laboratory isomerisation and reduction of an isomeric mixture of oleanenes was carried out to investigate the origin of oleanane (18(beta)-oleanane) and 18(alpha)-oleanane. Laboratory results indicated that oleanane was mainly derived from olean-18-ene, while 18(alpha)-oleanane was derived from 18(alpha)-olean-12-ene. Analysis of oleanene/oleanane abundances in a sedimentary sequence from Indonesia provided results consistent with laboratory evidence showing that 18(alpha)- olean-12-ene, rather than oleanane, is the main sedimentary precursor of 18(alpha)- oleanane.
17
Roberts, Mark. "Assessment of glomerular dynamics in human pregnancy using theoretical analysis and dextran sieving coefficients." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336811.
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Riström, Emilia. "Siktning som saneringsmetod för metallförorenad mark." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-105103.
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Toxic metals contaminate soil worldwide and thus serve as sever environmental threat. Therefore the purposes of this study were to investigate in which soil fractions that different heavy metals (Fe, As, Cu, Zn and Pb) could be found in contaminated soils and if it is possible to use sieving as a method for decontamination. Soil samples were collected from three different locations, the Nasa silver mine, the Blaiken-mine and Svalget environmental station. The samples were oven dried and later on sieved into six different fractions 8mm, 4 mm, 0.5 mm, 0.250mm, 0.063 mm and <0.063 mm. The fractions 4 mm, 0.5 mm and <0.063 mm from each location were analyzed in an x-ray fluorescence detector. The results showed that in general the smallest fractions contained the highest concentration of heavy metals which was very clear for Pb where 5 out of 6 samples had the highest concentration in the smallest fraction. The highest concentration of Cu (1147 ppm) and Zn (1117 ppm) were found in the smallest fraction in samples from the location Svalget. The highest concentration of Pb (10042 ppm) was also found in the smallest fraction in samples from Blaiken. In similarity the highest concentration of As (13305 ppm) was found in the smallest fraction in samples from the Nasa mine. However, in most samples the difference between the smallest fractions and the coarser material was small. Sieving may therefore not be the best way to decontaminate soil because even the larger fractions contained high concentrations of heavy metals.
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Xing, Yang. "Asymptotic behavior of Bayesian nonparametric procedures /." Umeå : Dept. of Forest Economics, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200935.pdf.
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Challa, Ravi Kumar. "FRACTIONATION OF SOYBEAN MEAL, COTTONSEED MEAL AND WHEAT MIDDLINGS USING COMBINATION OF SIEVING AND AIR CLASSIFICATION." MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-10022009-105240/.
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Fiber separation from these animal feeds could increase the protein and hence increase the value of the animal feed. The objective of the study was to evaluate the combination of sieving and air classification for fiber separation from soybean meal (SBM), cottonseed meal (CSM) and wheat middlings (WM). The effect of yields of lighter fractions on fiber separation from size fractions was also investigated. At low yields of lighter fraction (5%), the quantity of fiber product separated was 3.7, 1.3 and 4.8% by weight of SBM, CSM and WM respectively. At high yields of lighter fractions (15%), the quantity of fiber product separated was 8.9, 3.5 and 11% by weight of SBM, CSM and WM respectively. For CSM and SBM, the enhanced product contained 0.6 to 2.0% higher protein content than unprocessed feed. For WM, the enhanced product contained 0.2 to 0.7% higher protein content than unprocessed feed.
21
Lin, Xi [Verfasser], and Mathias [Akademischer Betreuer] Ulbricht. "Novel magneto-responsive ultrafiltration membranes for remote controlled switchable molecular sieving / Xi Lin ; Betreuer: Mathias Ulbricht." Duisburg, 2017. http://d-nb.info/1127527681/34.
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Mace, Amber. "Multiscale Modeling of Molecular Sieving in LTA-type Zeolites : From the Quantum Level to the Macroscopic." Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-113024.
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LTA-type zeolites with narrow window apertures coinciding with the approximate size of small gaseous molecules such as CO2 and N2 are interesting candidates for adsorbents with swing adsorption technologies due to their molecular sieving capabilities and otherwise attractive properties. These sieving capabilities are dependent on the energy barriers of diffusion between the zeolite pores, which can be fine-tuned by altering the framework composition. An ab initio level of theory is necessary to accurately describe specific gas-zeolite interaction and diffusion properties, while it is desirable to predict the macroscopic scale diffusion for industrial applications. Hence, a multiscale modeling approach is necessary to describe the molecular sieving phenomena exhaustively. In this thesis, we use several different modeling methods on different length and time scales to describe the diffusion driven uptake and separation of CO2 and N2 in Zeolite NaKA. A combination of classical force field based modeling methods are used to show the importance of taking into account both thermodynamic, as well as, kinetic effects when modeling gas uptake in narrow pore zeolites where the gas diffusion is to some extent hindered. For a more detailed investigation of the gas molecules’ pore-to-pore dynamics in the material, we present a procedure to compute the free energy barriers of diffusion using spatially constrained ab initio Molecular Dynamics. With this procedure, we seek to identify diffusion rate determining local properties of the Zeolite NaKA pores, including the Na+-to-K+ exchange at different ion sites and the presence of additional CO2 molecules in the pores. This energy barrier information is then used as input for the Kinetic Monte Carlo method, allowing us to simulate and compare these and other effects on the diffusion driven uptake using a realistic powder particle model on macroscopic timescales.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.
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Mori, Keita. "Increase of Total Nephron Albumin Filtration and Reabsorption in Diabetic Nephropathy." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225488.
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Aboud, Maurice J. "The Development of Direct Ultra-Fast PCR for Forensic Genotyping Using Short Channel Microfluidic Systems With Enhanced Sieving Matrices." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/715.
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There are situations in which it is very important to quickly and positively identify an individual. Examples include suspects detained in the neighborhood of a bombing or terrorist incident, individuals detained attempting to enter or leave the country, and victims of mass disasters. Systems utilized for these purposes must be fast, portable, and easy to maintain. The goal of this project was to develop an ultra fast, direct PCR method for forensic genotyping of oral swabs.
The procedure developed eliminates the need for cellular digestion and extraction of the sample by performing those steps in the PCR tube itself. Then, special high-speed polymerases are added which are capable of amplifying a newly developed 7 loci multiplex in under 16 minutes. Following the amplification, a postage stamp sized microfluidic device equipped with specially designed entangled polymer separation matrix, yields a complete genotype in 80 seconds. The entire process is rapid and reliable, reducing the time from sample to genotype from 1-2 days to under 20 minutes. Operation requires minimal equipment and can be easily performed with a small high-speed thermal-cycler, reagents, and a microfluidic device with a laptop. The system was optimized and validated using a number of test parameters and a small test population. The overall precision was better than 0.17 bp and provided a power of discrimination greater than 1 in 106.
The small footprint, and ease of use will permit this system to be an effective tool to quickly screen and identify individuals detained at ports of entry, police stations and remote locations. The system is robust, portable and demonstrates to the forensic community a simple solution to the problem of rapid determination of genetic identity.
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Milne, Jane E. C. "Renal reserve in human pregnancy in health and disease : elucidation of mechanisms using neutral dextran sieving coefficients and biomathematical modelling." Thesis, University of Newcastle upon Tyne, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405071.
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Kirshanova, Elena [Verfasser], Alexander [Gutachter] May, and Nils-Gregor [Gutachter] Leander. "Complexity of the learning with errors problem and memory-efficient lattice sieving / Elena Kirshanova ; Gutachter: Alexander May, Nils-Gregor Leander." Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1123283508/34.
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El, Khatib Wael. "Boundary Conditions for Granular Flows at Penetrable Vibrating Surfaces: Applications to Inclined Flows of Monosized Assemblies and to Sieving of Binary Mixtures." Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-dissertations/186.
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The purpose of this work is to study the effects of boundaries on granular flows down vibrating inclines, on segregation in granular mixtures induced by boundary vibrations, and on flows of granular mixtures through vibrating sieves. In each case, we employ techniques borrowed from the kinetic theory to derive an appropriate set of boundary conditions, and combine them with existing flow theories to calculate the profiles of solid volume fraction, mean velocity, and granular temperature throughout the flows. The boundaries vibrate with full three-dimensional anisotropy in a manner that can be related to their amplitudes, frequencies, and phase angles in three independent directions. At impenetrable surfaces (such as those on the inclines), the conditions derived ensure that momentum and energy are each balanced at the boundary. At penetrable surfaces (such as sieves), the conditions also ensure that mass is balanced at the boundary. In these cases, the momentum and energy balances also are modified to account for particle transport through the boundary. Particular interest in all the applications considered here is in how the details of the boundary geometry and the nature of its vibratory motion affect the resulting flows. In one case, we derive conditions that apply to a monosized granular material that interacts with a bumpy, vibrating, impenetrable boundary, and predict how such boundaries affect steady, fully developed unconfined inclined flows. Results indicate that the flows can be significantly enhanced by increasing the total energy of vibration and are more effectively enhanced by normal vibration than by tangential vibration. Regardless of the direction of vibration, the bumpiness of the boundary has a profound effect on the flows. In a second case, we derive conditions that apply to a binary granular mixture that interacts with a flat, vibrating, penetrable sieve-like boundary, and predict how such boundaries affect the process in which the particles pass through the sieve. In the special case in which the particles are all the same size, the results make clear that energy is more effectively transmitted to the assemblies when either the total vibrational energy or the normal component of the vibrational energy is increased, but that an increase in the energy transferred to the material can sometimes actually decrease the flow rates through the sieve. Consequently, at any instant of time in the sieving process, there is an optimum level of vibrational energy that will maximize the flow rate. For the sieving of binary granular assemblies, the physics associated with the effects of energy transfer on the flow rates still applies. However, in these cases, the flows through the sieve are also profoundly affected by segregation that occurs while the particles reside on sieve before the pass through. For this reason, we also isolate the segregation process from the sieving process by considering the special case in which the holes in the vibrating sieve are too small to allow any particles to pass through. In this case, the results show that under most circumstances the region immediately adjacent to the vibrating surface will be populated almost entirely by the smaller particles or by the more dissipative particles if there is no size disparity, and that the reverse is true in a second region above the first.
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Ramamoorthy, Thiagarajan. "Mechanical Behavior of Membranes in Electrostatic Precipitators." Ohio University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1125868299.
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Elskamp, Frederik [Verfasser], Harald [Akademischer Betreuer] Kruggel-Emden, Harald [Gutachter] Kruggel-Emden, and Alfred P. [Gutachter] Weber. "A framework for the derivation of dynamic process models for sieving / Frederik Elskamp ; Gutachter: Harald Kruggel-Emden, Alfred P. Weber ; Betreuer: Harald Kruggel-Emden." Berlin : Technische Universität Berlin, 2019. http://d-nb.info/1176623443/34.
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Moran, Paul. "The renal effects of atrial natriuretic peptide in normal and preeclamptic pregnancy including the renal handling of macromolecules using Dextran sieving data and biomathematical modelling." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324862.
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Peter, Prince Chinedu. "Implication of tillage, texture and mineralogy on the sieving efficiency, physical-based soil organic matter and aggregate stability of some soils in the Eastern Cape." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/2710.
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Soil structure and its associated physical properties are essential soil components. Soil texture and mineralogy are inherent soil properties that influence soil management. This study assessed the implication of tillage, texture and mineralogy on soil sieving, aggregate stability indices and physical fractions of organic matter in soils of Eastern Cape Province of South Africa. An Iris FTLVH – 0200 digital electromagnetic sieve shaker (Filtra Vibraciόn SL Spain), was used to determine settings for sieving efficiency. Mean weight diameter (MWD), water stable aggregate (WSA), state of aggregation (SA), dispersion ratio (DR), water dispersible clay (WDC), clay dispersion ratio (CDR), clay flocculation index (CFI), and potential structural deformation index (PSDI) were aggregate stability indices evaluated to check for sensitivity in evaluating aggregate stability of soils under two tillage systems and physical fractions of carbon and nitrogen in soils of Eastern Cape Province. The T4I3P2 and T4I4P3 settings were sensitive under tillage and T4I1P4, T3I4P3 and T4I4P3 were sensitive under mineralogical considerations for sieving efficiency. The total carbon in soils under conventional tillage (CT) was 17.7 g/kg and in soils under no tillage (NT) it was 15.8 g/kg. The total carbon content in the clay fraction of soils under CT was 24.1 percent higher than the total carbon content in the clay fraction of soils under NT. The total nitrogen content in the clay fraction of soils under CT was 5.4 percent higher than the total nitrogen content in the soils under NT. The total carbon in the sandy loam (SL) textured soils was 17.4 g/kg and in the sandy clay loam (SCL) textured soils it was 17.1 g/kg. The total nitrogen in SL soils was 3.7 g/kg and in SCL soils it was 3.7 g/kg. The clay fraction had higher total carbon than other fractions in Sl and SCL soils. The higher values of nitrogen were observed in the silt fraction for SL soils and clay fraction for SCL soils. The total carbon in the soils dominated with kaolinite was 17.3 g/kg and in quartz dominated soils the value was 16.9 g/kg. The total nitrogen in the soils dominated with kaolinite was 3.7 g/kg and in the soils dominated with quartz the value was 3.7 g/kg. For soils under NT the WDC was 135.8 g/kg and for soils under CT it was 139.7 g/kg. The ASC was 72.5 for soils under NT and 92.0for soils under CT. The DR was 0.9 for soils under NT and 0.8 for soils under CT. The CFI was 0.5 for soils under NT and 0.5 for soils under CT. The CDR was 0.5 for soils under NT and 0.5 for soils under CT. The MWDw was 1.6 mm for soils under NT and 1.4 mm for soils under CT. The MWDd was 4.0 mm for soils under NT and 4.0 for soils under CT. The percent WSA > 0.25 mm was 61.7 percent for soils under NT and 56.2 percent for soils under CT. The PSDI was 55.2 percent for soils under NT and 61.15 percent for soils under CT. The SA was 43.2 percent for soils under NT and 37.89 percent for soils under CT. The WDC was 125.7 g/kg for SCL soils and 151.4 g/kg for SL soils. The CDR was 0.5 for both SCL and SL soils. The DR was 0.9 for SCL soils and 0.8 for SL soils. The CFI was 0.5 for both SCL and SL soils. The ASC was 56.2 g/kg for SCL soils and 115 g/kg for SL soils. The MWDw was 1.5 mm for SCL soils and 1.4 mm for SL soils. The MWDd was 3.6 mm for SCL soils and 3.6 mm for SL soils. The percent WSA > 0.25 mm was 53.0 percent for SCL soils and 62.5 percent for SL soils. The PSDI was 59.2 percent for SCL soils and 59.7 percent for SL soils. The SA was 33.6 percent for SCL soils and 45.2 percent for SL soils. The WDC was 313.3 g/kg for kaolinitic soils and 120.7 g/kg for quartz dominated soils. The CDR was 0.5 for kaolinitic soils and 0.5 for quartz dominated soils. The DR was 0.9 for kaolinitic soils and 0.8 for quartz dominated soils. The CFI was 0.5 for kaolinitic soils and 0.5 for quartz dominated soils. The ASC was 110.0 g/kg for kaolinitic soils and 101.7 g/kg for quartz dominated soils. The WSA > 0.25 mm was 57.3 percent for quartz dominated soils and 68.4 percent for kaolinitic soils. The MWDw was 1.6 mm for quartz dominated soils and 0.8 mm for kaolinitic soils. The MWDd was 3.6 mm for quartz dominated soils and 3.4 mm for kaolinitic soils. The PSDI was 56.3 for quartz dominated soils and 76.0 for kaolinitic soils.
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Supronowicz, Barbara [Verfasser], Thomas [Akademischer Betreuer] Heine, Ulrich [Akademischer Betreuer] Kleinekathöfer, and Petko [Akademischer Betreuer] Petkov. "Computational Studies on Selective Adsorption and Molecular Sieving in HKUST-1 Metal – Organic Framework / Barbara Supronowicz. Betreuer: Thomas Heine. Gutachter: Thomas Heine ; Ulrich Kleinekathöfer ; Petko Petkov." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2014. http://d-nb.info/1087292174/34.
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Cai, Yue. "New Perspectives of Quantum Analogues." UKnowledge, 2016. http://uknowledge.uky.edu/math_etds/34.
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In this dissertation we discuss three problems. We first show the classical q-Stirling numbers of the second kind can be expressed more compactly as a pair of statistics on a subset of restricted growth words. We extend this enumerative result via a decomposition of a new poset which we call the Stirling poset of the second kind. The Stirling poset of the second kind supports an algebraic complex and a basis for integer homology is determined. A parallel enumerative, poset theoretic and homological study for the q-Stirling numbers of the first kind is done. We also give a bijective argument showing the (q, t)-Stirling numbers of the first and second kind are orthogonal. In the second part we give combinatorial proofs of q-Stirling identities via restricted growth words. This includes new proofs of the generating function of q-Stirling numbers of the second kind, the q-Vandermonde convolution for Stirling numbers and the q-Frobenius identity. A poset theoretic proof of Carlitz’s identity is also included. In the last part we discuss a new expression for q-binomial coefficients based on the weighting of certain 01-permutations via a new bistatistic related to the major index. We also show that the bistatistics between the inversion number and major index are equidistributed. We generalize this idea to q-multinomial coefficients evaluated at negative q values. An instance of the cyclic sieving phenomenon related to flags of unitary spaces is also studied.
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Elfverson, Cajsa. "Analysis of physical and chemical properties of fractionated grains and seeds with an emphasis on barley /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5708-4.pdf.
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Miodrag, Milutinov. "Modelovanje, simulacija i merenje snage gubitaka u feritnim jezgrima u frekvencijskom opsegu do 1 GHz." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2017. https://www.cris.uns.ac.rs/record.jsf?recordId=104000&source=NDLTD&language=en.
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U radu je predložena modifikovana vatmetarska metoda za merenje snage gubitaka u toroidnim feritnim jezgrima koja je prilagođena osciloskopima male ulazne impedanse. Metoda je verifikovana na komercijalnim uzorcima od Mn-Zn i Ni-Zn feritnih materijala. Metoda je upotrebljena za merenje kompleksne permeabilnosti i gustine snage gubitaka dodatno obrađenih komercijalnih Mn-Zn feritnih prahova. Utvrđeno je da se dodatnim tehnološkim procesima (mlevenjem i prosejavanjem) početnog komercijanog praha mogu napraviti feritna jezgra manje gustine snage gubitaka i veće permeabilnosti.The thesis proposes a modified Watt-meter method for measuring core loss of ferrite cores, which is adjusted to oscilloscopes with the small input impedance. The method is verified on comercial Mn-Zn and Ni-Zn ring cores. The method is used to measure the influence of starting powder sieving and milling on the core loss density and permeability of Mn-Zn ferrite. The experimental results and calculations show the significance of the additional milling and sieving process on magnetic properties of Mn-Zn ferrite in the frequency range from 0.1MHz to 10MHz. These processes increase the relative permeability about 3 times and decrease the core loss 4 times by milling of the starting powder.
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Zhang, Naiyuan. "Hydrogen Isotope Separation in Metal-Organic Frameworks." Oberlin College Honors Theses / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1532013686771173.
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Lambert, Anne. "La protéolyse par les bactéries du rumen : étude dynamique de la libération et de l'utilisation des peptides caractérisés par leur poids moléculaire." Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL085N.
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L’ensemble de ce travail vise à améliorer la compréhension des mécanismes conduisant à la libération, l'accumulation et l'utilisation des peptides par les bactéries. Afin d'étudier l'effet de la taille des peptides sur leur dégradation et leur prélèvement, nous avons réalisé différentes mesures cinétiques, in vitro puis in vivo. Pour les études in vitro, en ajoutant à un hydrolysat protéique total non marqué différentes fractions marquées extraites d'un hydrolysat similaire, et caractérisées par leur poids moléculaire, nous avons pu suivre le devenir successivement le devenir de chacune de ces fractions au sein d'un mélange complexe de peptides. In vitro, les peptides de faibles poids moléculaires (1 000 à 2 000 Da) sont assimilables beaucoup plus rapidement que les peptides les plus longs (5 000 à 10 000 Da). Les taux de disparition du marquage diffèrent aussi pour chaque fraction. Les peptides les plus longs disparaissent plus rapidement que les moyens, eux-mêmes hydrolysés plus rapidement que les petits. Le prélèvement des petits peptides semble être l'étape limitant l'utilisation de l'ensemble des peptides par les bactéries. Grâce à une cinétique d'hydrolyse de poids marqué au ¹⁵N in vivo, il a été possible de compléter le travail réalisé in vitro. La vitesse d'hydrolyse des protéines en peptides est un peu plus influencée par une diminution de l'accessibilité des protéines aux enzymes que par un apport plus élevé d'azote soluble. Le prélèvement des peptides de moins de 1 000 Da se révèle à nouveau être l'étape limitant de l'utilisation des peptides pris dans leur ensemble. La dégradation in sacco du poids montre que l'essentiel de l'azote contenu dans celui-ci disparait en 2 heures. 65% de l'azote total est constitué d'azote rapidement soluble et/ou fermentescible. Sa disparition est aussi observée sur les profils électrophorétiques réalisés à partir des protéines résiduelles et se répercute sur les quantités de peptides obtenues après hydrolyse enzymatique. In sacco, la majeure partie des peptides libérables par hydrolyse d'une source protéique donnée semble donc l'être dans les deux heures suivant l'ingestion de cette source, à partir d'azote rapidement fermentescible. L’originalite de notre travail est d'avoir cherche à déterminer à quel niveau de la chaine d'hydrolyse se produit l'accumulation et donc à mieux cerner les facteurs limitant de l'utilisation de l'azote protéique par les bactéries. Ceci a été permis grâce à l'utilisation combinée de deux techniques souvent employées séparément : marquage des peptides et séparation par tamisage moléculaire.
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Shinbrough, Kai. "Infrared and Thermal-Desorption Spectroscopy of H2 and D2 in Metal Organic Frameworks." Oberlin College Honors Theses / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1495632169708899.
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Pereira, Monique Cristina Viana. "Modelagem Fenomenológica do Escoamento de Fluido de Perfuração em Peneiras Vibratórias." Universidade Federal de Uberlândia, 2017. http://dx.doi.org/10.14393/ufu.di.2018.219.
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FAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisPetrobrás - Petróleo Brasileiro S.A
Os fluidos de perfuração são substâncias injetadas no poço cuja principal função é trazer à superfície os cascalhos de rocha produzidos durante a perfuração. A separação e a reutilização do fluido de perfuração são de suma importância para que se atenda às exigências da legislação ambiental em relação ao descarte de resíduos. Além disso, é imprescindível a recuperação do fluido utilizado por questões de redução de custos da etapa de perfuração. O objetivo do presente estudo foi desenvolver um modelo matemático para a separação entre cascalho e fluido de perfuração por peneiras vibratórias com base nos princípios da dinâmica newtoniana e da lei de conservação de massa. Para tanto a tela da peneira foi considerada um leito empacotado de espessura muito fina e com inclinação ascendente. Correlações para a queda de pressão foram analisadas e uma nova correlação foi proposta com base em metodologias indicadas na literatura. O comportamento do fluido foi avaliado para a variação nos seguintes parâmetros: viscosidade plástica, tensão limite de escoamento, coeficiente de escoamento, inclinação da tela e força-g. O modelo não se mostrou sensível a variações na tensão limite de escoamento do fluido. Os demais parâmetros mostraram significativa influência sobre o comprimento de tela molhada. Os resultados obtidos estão de acordo com o relatado pela literatura e mostram que o modelo desenvolvido é adequado para a descrição do processo de peneiramento vibratório.
Drilling fluids are substances injected into the well whose main function is to suspend drilled solids, remove them from the well bore and release them at the surface. Separation and reuse of drilling fluids is of great importance to fulfill the requirements of environmental legislation regarding waste disposal. In addition, it is essential to recover the drilling fluid in order to reduce costs of the drilling process. The objective of the present study was to develop a mathematical model based on the principles of Newtonian dynamics and the law of mass conservation for the process of removal of drilled cuttings from drilling fluid using vibrating screens. For this purpose, the sieve screen was considered to be a very thin packed bed and tilted upward. Pressure drop correlations were analyzed and a new correlation was proposed based on methodologies indicated in the literature. The behavior of the fluid was evaluated for the variation in the following parameters: plastic viscosity, yield stress, flow coefficient, tilt of the screen and g factor. The model was not sensitive to variations in the yield stress of the fluid while other parameters showed a significant influence on wet screen length. Obtained results are in agreement with the reported ones in the literature and show that the developed model is suitable for the description of the process of vibrating screening.
Dissertação (Mestrado)
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Smelík, Lukáš. "Návrh metodiky stanovení součinitele drsnosti otevřených koryt." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-234558.
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Determination of immeasurable parameter, the Manning’s roughness coefficient, is a complex problem of open channel hydraulics for more than 200 years. Now it doesn’t exists a method for determining an exact value of 1D roughness coefficient for computation water levels in watercourses. Doctoral thesis is focused for comparing different approaches to determine a roughness coefficient, especially for empirical equations. It were sought empirical equations, which are suitable for wide spectrum of water stages, types of bed material, channel shapes and channel dimensions. Selected equations were sorted on the base of two methods by the best values of medians and standard deviations of measured and computed values of roughness coefficients. Furthermore, it were compared qualities of roughness coefficient determination by tables, by photographic catalogs, CES software and by Cowan’s method, which has been extended and recalibrated. The computed values of roughness coefficients by those four methods were compared with values from own measurements in 27 locations in watercourses near of Brno and Frýdek-Místek. Also it were compared the grain size curves determined by sieving, by Wolman’s method and by Subjective estimation. Doctoral thesis is marginally focused for beginning of sediment movement, roughness coefficient of bedforms (dunes), grass and trees.
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Sievi, Eeva. "Fate of mammalian golgi sialyltransferases in yeast." Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/eri/biote/vk/sievi/.
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Contardo, Martínez Santiago. "Tres tristes tigres: mecanismos para el descentramiento de un cuerpo: de Alejandro Sieveking a Raúl Ruiz." Tesis, Universidad de Chile, 2013. http://www.repositorio.uchile.cl/handle/2250/116191.
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Informe de Seminario para optar al grado de Licenciado en Lengua y Literatura Hispánica mención LiteraturaEn 1967 se estrena en Chile la obra dramática Tres tristes tigres de Alejandro Sieveking. Tan solo un año después es filmada en el mismo país una película homónima por Raúl Ruiz. Una mera coincidencia de títulos queda descartada de plano cuando vemos aparecer en la pantalla personajes con los mismos nombres que en la obra dramática, ¿Por qué recurrir a tales asociaciones? Digamos enseguida que la película, si bien, parece buscar en algunos momentos apegarse lo más posible a la obra parasitada, en otros (cuantitativamente más numerosos) se aparta aparentemente de todo nexo tanto en el plano del contenido como de la forma. Se ve, por ello, anulada la suspicacia de advertir en el desarrollo de la cinta una sequía creativa en la que se busca el éxito comercial a través de una “adaptación” exitosa (en todo caso, no son las motivaciones genésicas las que aquí nos convocan). Por otro lado, queda descartada también la hipótesis ingenua de la interpretación. Lo cual supondría entender la película de Ruiz como una intermediación que busca desentrañar significados contenidos con anterioridad (de allí la etimología monetaria de la palabra). De ningún modo. La apertura retórica que acusa este dispositivo aparece –si se ha leído la película- como una textualidad desviada de cualquier concentración semántica eventualmente recolectada de los signos dispuestos en/por la obra de Sieveking. De modo tal, que nos encontramos ante la aparición de nuevos signos divergentes, ciertas reminiscencias acompañadas de inmediatos desvíos. Pero decir que no se trata de una interpretación no quiere decir que no hay un proceso de lectura en juego. Por el contrario –y aquí se esboza una de las conjeturas obtenidas- es ella la naturaleza de la película filmada: filmar como leer o leer como filmar,no olvidando, así, la naturaleza verbal del proceso (movedizo y no substancial). Lo siguiente quiere ser un análisis anatómico. Una mirada a la mirada y una lectura a la lectura.
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Vlk, Radomír. "Návrh asfaltových směsí typu SAL určených pro opravu cementobetonových krytů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227301.
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This master's thesis describes how to use the asphalt layer called Stress Absorbing Layer (SAL) and comparises it with other types of SAL with different types of asphalt binders. In the first theoretical part is SAL generally described. In the second part is SAL practically tested and described.
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CARUSO, MATTEO FRANCESCO. "Ottimizzazione del processo produttivo degli acari della specie Dermatophagoides e dei loro allergeni." Doctoral thesis, Università Cattolica del Sacro Cuore, 2020. http://hdl.handle.net/10280/72219.
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Questa tesi è frutto della collaborazione tra l'Università e Lofarma S.p.A., un’azienda farmaceutica italiana leader nel settore che produce preparati per pazienti allergici come kit diagnostici e immunoterapie. A tale scopo nel reparto di Acarologia ogni anno vengono allevati e raccolti decine di chilogrammi di acari adulti e, dopo alcune manipolazioni, utilizzati nel reparto produttivo come materia prima per la maggior parte delle formulazioni. Lo scopo di questo progetto è analizzare l'attuale metodo di produzione e studiare se alcuni passaggi potrebbero essere ottimizzati per migliorare la resa, il tasso di produzione e la qualità della materia prima, cercando nel contempo di ridurre costi e tempi di lavorazione.
La ricerca è stata suddivisa in 2 aree principali: 1) Procedure di Allevamento (valutazione della qualità della dieta e del ceppo allevato) e 2) Manipolazioni della Materia Prima (ottimizzazione del processo di pulizia e valorizzazione della materia prima). Tra questi, i risultati più significativi sono stati raggiunti nella sezione Manipolazione delle Materie Prime, dove viene descritto un nuovo processo di rifinitura in grado di ottenere rese finali più elevate in tempistiche più brevi.
Dopo aver analizzato l'intero ciclo produttivo, è possibile concludere che, nel contesto del Reparto di Acarologia, è più conveniente procedere con una migliore manipolazione della materia prima piuttosto che modificare le attuali metodiche di allevamento, che sembrano già adatte per le esigenze di Lofarma.This thesis is based on collaboration between University and Lofarma S.p.A., a leading Italian pharmaceutical company which produce preparation for allergic patients like diagnostic kits and immunotherapies. To this purpose every year dozens of kilograms of adult mites are reared and collected in the Acarology department and, after manipulations, used in the Production Department as raw material for most of the preparation. The aim of this project is to analyze the current production methodology of Acarology department and investigate if some steps could be optimized to improve the yield, the production rate and the quality of the raw material while trying to reduce costs and processing times. The research has been divided in 2 main areas: 1) Rearing Procedures (quality assessment about the diet and the strain enacted) and 2) Raw Material Manipulations (optimization of the refining process and valorization of the Raw Material). Between those, most significant results have been achieved in the Raw Material Manipulation section, where is described a novel refining process capable of obtaining higher final yields in a shorter working time. After analyzing the whole manufacturing cycle, is possible to conclude that, within the context of the Acarology Department, is more convenient to proceed with a better manipulation of the raw material in the refining process rather than modifying the actual rearing procedure, which is already suitable for Lofarma needs.
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Sieveking, Dirk [Verfasser], and Reinhard [Akademischer Betreuer] Lindner. "Studie zur Gewinnung psychoanalytischer Parameter für die empathiebasierte Beurteilung des Gelingens psychotherapeutischer Beziehungen / Dirk Sieveking ; Betreuer: Reinhard Lindner." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1164593552/34.
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Sievi, Gabriel [Verfasser], Peter [Akademischer Betreuer] Wasserscheid, and Peter [Gutachter] Wasserscheid. "Elektrochemische Oxidation von 2-Propanol in einer Direkt-Brennstoffzelle / Gabriel Sievi ; Gutachter: Peter Wasserscheid ; Betreuer: Peter Wasserscheid." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/122050596X/34.
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Sieven, Ramon [Verfasser]. "Kommunale Energieerzeugung in der Energiewende : Kommunalrechtliche Problemstellungen und Gestaltungsoptionen am Beispiel der Elektrizitätserzeugung durch Erneuerbare Energien im Vergleich zur Privatwirtschaft / Ramon Sieven." Göttingen : Universitätsverlag Göttingen, 2019. http://d-nb.info/1177795876/34.
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Poltorak, Lukasz. "Modification électrochimique de l'interface liquide - liquide avec de la silice mésoporeuse." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0105/document.
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Ce travail combine l'électrochimie à l'interface liquide - liquide avec le procédé sol - gel pour la modification interfaciale avec de la silice mésoporeuse. Dans la première partie de ce travail, l’interface liquide – liquide macroscopique a été utilisée pour séparer la solution aqueuse de l'espèce de précurseur de silice hydrolysées (tétraéthoxysilane (TEOS)) de l'agent tensioactif cationique (cethyltrimethylammonium (CTA+) qui a agi comme un template et a été dissous dans le dichloroéthane. Le dépôt de matériau de silice a été déclenchée par le transfert du CTA+ à partir de la phase organique vers la phase aqueuse. CTA+ qui a transféré à la phase aqueuse a catalysé la réaction de condensation de la silice sur l’interface liquide – liquide. Le dépôt de silice à des interfaces liquide – liquide miniaturisées était la deuxième partie de ce travail. Les dépôts stables sur le côté de l'interface ont été synthétisés in situ par voie électrochimique. La stabilité mécanique des dépôts de silice permis un traitement thermique de la silice. Basé sur les techniques d’imagerie (par exemple SEM) il a été constaté que les dépôts forment des hémisphères pour des temps plus long. La réaction interfaciale a également été suivie in situ par spectroscopie Raman confocale. Caractéristiques moléculaires de l'interface ont été modifiées de manière spectaculaire une fois les espèces CTA+ ont été transférés à la phase aqueuse. Les interfaces liquide – liquide miniaturisés et modifiés ont également été évaluée avec le transfert voltampérométriqueThis work combines the electrochemistry at the interface between two immiscible electrolyte solutions (ITIES) with the Sol – Gel process of silica leading to an interfacial modification with mesoporous silica using soft template. In the first part of this work the macroscopic liquid – liquid interface was employed to separate the aqueous solution of the hydrolyzed silica precursor species (tetraethoxysilane (TEOS)) from the cationic surfactant (cethyltrimethylammonium (CTA+)) dissolved in the dichloroethane. The silica material deposition was controlled by the electrochemical CTA+ transfer from the organic to the aqueous phase. Template transferred to the aqueous phase catalyzed the condensation reaction and self-assembly resulting in silica deposition at the interface. Silica deposition at the miniaturized ITIES (membranes supporting array of micrometer in diameter pores were used in this regard) was the second part of this work. Silica interfacial synthesis performed in situ resulted in stable deposits growing on the aqueous side of the interface. Mechanical stability of the supported silica deposits allowed further processing – silica material was cured. Based on imaginary techniques (e.g. SEM) it was found that deposits forms hemispheres for longer experimental time scales. Interfacial reaction was also followed with in situ confocal Raman spectroscopy. Molecular characteristics of the interface were changed dramatically once CTA+ species were transferred to the aqueous phase. Array of microITIES modified with silica was also assessed by ion transfer voltammetry
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Yen-ChuanChang and 張延全. "A Virtual Sample Sieving Mechanism." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/61245682450609259631.
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碩士國立成功大學
高階管理碩士在職專班(EMBA)
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Past small sample learning methods, utilizing virtual sample generation (VSG) methods has been shown to effectively enhance the outcomes of machine learning algorithms. However, most of the VSG methods do not have a clear definition on how to control the quality of the generated virtual samples; such as the diffusion neural network (DNN) proposed by Huang and Moraga (2004). Although the considerations are related to the sample generation process, DNN is limited in the correlation between attributes which must be greater than 0.9. In addition, the mega-trend-diffusion (MTD) technique proposed by LI et al. (2007) assumes the relationship between attributes is independent, i.e. the correlations are not considered in the sample generation process. This assumption would thus lead the generated samples to excess scopes of the populations. Although the information abstracted from small datasets is not convincible, the small datasets are parts of the populations. As well as the characters of the small datasets are reserved in the virtual samples, the rationality of them still can be ensured. Therefore, this study proposes a virtual sample sieving mechanism, with a small sample correlation between attributes for sample selection. The experimental results show that the characters of small datasets can be reserved when the virtual samples created by MTD are sieved by the proposed mechanism. In addition, the prediction accuracy of the multiple linear regressions and the back-propagation neural networks can further be improved.
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Rhee, Donguk. "Cyclic Sieving Phenomenon of Promotion on Rectangular Tableaux." Thesis, 2012. http://hdl.handle.net/10012/7071.
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Cyclic sieving phenomenon (CSP) is a generalization by Reiner, Stanton, White of Stembridge's q=-1 phenomenon. When CSP is exhibited, orbits of a cyclic action on combinatorial objects show a nice structure and their sizes can be encoded by one polynomial.
In this thesis we study various proofs of a very interesting cyclic sieving phenomenon, that jeu-de-taquin promotion on rectangular Young tableaux exhibits CSP. The first proof was obtained by Rhoades, who used Kazhdan-Lusztig representation. Purbhoo's proof uses Wronski map to equate tableaux with points in the fibre of the map. Finally, we consider Petersen, Pylyavskyy, Rhoades's proof on 2 and 3 row tableaux by bijecting the promotion of tableaux to rotation of webs.
This thesis also propose a combinatorial approach to prove the CSP for square tableaux. A variation of jeu-de-taquin move yields a way to count square tableaux which has minimal orbit under promotion. These tableaux are then in bijection to permutations. We consider how this can be generalized.