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1
Zheng, Feng. "Thermophoretic force measurements of spherical and non-spherical particles /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/9874.
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Rydefalk, Staffan. "Particle Measurements Using Fluctuations in the Regular Transmittance of Light Through a Particle Dispersion : Concentration and Particles size - Theory, Measurement Principles and Applications for Pulp and Paper Production." Doctoral thesis, KTH, Industriell produktion, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10639.
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The regular transmittance of light or similar radiation through a flowing suspension of particles fluctuates because of the random occurrence of particles in the beam.In the work presented here, a theory for this fluctuating behaviour with the emphasison dispersions of mm-length slender cylindrical particles having circular crosssections is given. The particles in question are wood pulp fibres, which as a first approximation are considered to have a cylinder shape. Four possible measurementprinciples are described theoretically and experimentally. The four principles are for the measurement of concentration, length distribution characterized as lengthclasses, mean length, and mean width. The usefulness in industrial process monitoring of two of these principles is exemplified with pulp measurements. In order to estimate model errors, numerical simulations were used. Although other techniques such as image analysis may compete, the technique presented here is attractive because of the simplicity of the measurement device used.<br>QC 20100806
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Mills, E. "Transputer instrumentation for particle flow measurements." Thesis, Nottingham Trent University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328227.
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Wardoyo, Arinto Yudi. "Biomass burning : particle emissions, characteristics, and airborne measurements." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16492/1/Arinto_Wardoyo_Thesis.pdf.
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Biomass burning started to attract attention since the last decade because of its impacts on the atmosphere and the environmental air quality, as well as significant potential effects on human health and global climate change. Knowledge of particle emission characteristics from biomass burning is crucially important for the quantitative assessment of the potential impacts. This thesis presents the results of study aimed towards comprehensive characterization of particle emissions from biomass burning. The study was conducted both under controlled laboratory conditions, to quantify the particle size distribution and emission factors by taking into account various factors which may affect the particle characteristics, and in the field, to investigate biomass burning processes in the real life situations and to examine vertical profile of particles in the atmosphere.
To simulate different environmental conditions, a new technique has been developed for investigating particle emissions from biomass burning in the laboratory. As biomass burning may occur in a field at various wind speeds and burning rates, the technique was designed to allow adjustment of the flow rates of the air introduced into the chamber, in order to control burning under different conditions. In addition, the technique design has enabled alteration of the high particle concentrations, allowing conducting measurements with the instrumentations that had the upper concentration limits exciding the concentrations characteristic to the biomass burning.
The technique was applied to characterize particle emissions from burning of several tree species common to Australian forests. The aerosol particles were characterized in terms of size distribution and emission factors, such as PM2.5 particle mass emission factor and particle number emission factor, under various burning conditions. The characteristics of particles over a range of burning phases (e.g., ignition, flaming, and smoldering) were also investigated. The results showed that particle characteristics depend on the type of tree, part of tree, and the burning rate.
In particular, fast burning of the wood samples produced particles with the CMD of 60 nm during the ignition phase and 30 nm for the rest of the burning process. Slow burning of the wood samples produced large particles with the CMD of 120 nm, 60 nm and 40 nm for the ignition, flaming and smoldering phases, respectively. The CMD of particles emitted by burning the leaves and branches was found to be 50 nm for the flaming phase and 30 nm for the smoldering phase, under fast burning conditions. Under slow burning conditions, the CMD of particles was found to be between 100 to 200 nm for the ignition and flaming phase, and 50 nm for the smoldering phase.
For fast burning, the average particle number emission factors were between 3.3 to 5.7 x 1015 particles/kg for wood and 0.5 to 6.9 x 1015 particles/kg for leaves and branches. The PM2.5 emission factors were between 140 to 210 mg/kg for wood and 450 to 4700 mg/kg for leaves and branches. For slow burning conditions, the average particle number emission factors were between 2.8 to 44.8 x 1013 particles/kg for wood and 0.5 to 9.3 x 1013 particles/kg for leaves and branches, and the PM2.5 emissions factors were between 120 to 480 mg/kg for wood and 3300 to 4900 mg/kg for leaves and branches.
The field measurements were conducted to investigate particle emissions from biomass burning in the Northern Territory of Australia over dry seasons. The results of field studies revealed that diameters of particles in ambient air emissions were within the size range observed during laboratory investigations. The laboratory measurements found that the particles released during the controlled burning were of a diameter between 30 and 210 nm, depending on the burning conditions. Under fast burning conditions, smaller particles were produced with a diameter in the range of 30 to 60 nm, whilst larger particles, with a diameter between 60 nm and 210 nm, were produced during slow burning. The airborne field measurements of biomass particles found that most of the particles measured under the boundary layer had a CMD of (83 ± 13) nm during the early dry season (EDS), and (127 ± 6) nm during the late dry season (LDS). The characteristics of ambient particles were found to be significantly different at the EDS and the LDS due to several factors including moisture content of vegetation, location of fires related to the flight paths, intensity of fires, and burned areas. Specifically, the investigations of the vertical profiles of particles in the atmosphere have revealed significant differences in the particle properties during early dry season and late dry season. The characteristics of particle size distribution played a significant role in these differences.
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Wardoyo, Arinto Yudi. "Biomass burning : particle emissions, characteristics, and airborne measurements." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16492/.
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Biomass burning started to attract attention since the last decade because of its impacts on the atmosphere and the environmental air quality, as well as significant potential effects on human health and global climate change. Knowledge of particle emission characteristics from biomass burning is crucially important for the quantitative assessment of the potential impacts. This thesis presents the results of study aimed towards comprehensive characterization of particle emissions from biomass burning. The study was conducted both under controlled laboratory conditions, to quantify the particle size distribution and emission factors by taking into account various factors which may affect the particle characteristics, and in the field, to investigate biomass burning processes in the real life situations and to examine vertical profile of particles in the atmosphere. To simulate different environmental conditions, a new technique has been developed for investigating particle emissions from biomass burning in the laboratory. As biomass burning may occur in a field at various wind speeds and burning rates, the technique was designed to allow adjustment of the flow rates of the air introduced into the chamber, in order to control burning under different conditions. In addition, the technique design has enabled alteration of the high particle concentrations, allowing conducting measurements with the instrumentations that had the upper concentration limits exciding the concentrations characteristic to the biomass burning. The technique was applied to characterize particle emissions from burning of several tree species common to Australian forests. The aerosol particles were characterized in terms of size distribution and emission factors, such as PM2.5 particle mass emission factor and particle number emission factor, under various burning conditions. The characteristics of particles over a range of burning phases (e.g., ignition, flaming, and smoldering) were also investigated. The results showed that particle characteristics depend on the type of tree, part of tree, and the burning rate. In particular, fast burning of the wood samples produced particles with the CMD of 60 nm during the ignition phase and 30 nm for the rest of the burning process. Slow burning of the wood samples produced large particles with the CMD of 120 nm, 60 nm and 40 nm for the ignition, flaming and smoldering phases, respectively. The CMD of particles emitted by burning the leaves and branches was found to be 50 nm for the flaming phase and 30 nm for the smoldering phase, under fast burning conditions. Under slow burning conditions, the CMD of particles was found to be between 100 to 200 nm for the ignition and flaming phase, and 50 nm for the smoldering phase. For fast burning, the average particle number emission factors were between 3.3 to 5.7 x 1015 particles/kg for wood and 0.5 to 6.9 x 1015 particles/kg for leaves and branches. The PM2.5 emission factors were between 140 to 210 mg/kg for wood and 450 to 4700 mg/kg for leaves and branches. For slow burning conditions, the average particle number emission factors were between 2.8 to 44.8 x 1013 particles/kg for wood and 0.5 to 9.3 x 1013 particles/kg for leaves and branches, and the PM2.5 emissions factors were between 120 to 480 mg/kg for wood and 3300 to 4900 mg/kg for leaves and branches. The field measurements were conducted to investigate particle emissions from biomass burning in the Northern Territory of Australia over dry seasons. The results of field studies revealed that diameters of particles in ambient air emissions were within the size range observed during laboratory investigations. The laboratory measurements found that the particles released during the controlled burning were of a diameter between 30 and 210 nm, depending on the burning conditions. Under fast burning conditions, smaller particles were produced with a diameter in the range of 30 to 60 nm, whilst larger particles, with a diameter between 60 nm and 210 nm, were produced during slow burning. The airborne field measurements of biomass particles found that most of the particles measured under the boundary layer had a CMD of (83 ± 13) nm during the early dry season (EDS), and (127 ± 6) nm during the late dry season (LDS). The characteristics of ambient particles were found to be significantly different at the EDS and the LDS due to several factors including moisture content of vegetation, location of fires related to the flight paths, intensity of fires, and burned areas. Specifically, the investigations of the vertical profiles of particles in the atmosphere have revealed significant differences in the particle properties during early dry season and late dry season. The characteristics of particle size distribution played a significant role in these differences.
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Zhang, Zheng. "RESISTIVE PULSE SENSORS FOR POLLEN PARTICLE MEASUREMENTS." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1145070142.
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Raghuvanshi, Anurag. "Particle filter with Hyperbolic Measurements and Geometry Constraints." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1366724596.
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Jessen, Wilhelm. "Particle image velocimetry measurements of film cooling flows /." Aachen : Mainz, 2008. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=017075640&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Thornton, Jenna Louise. "Ice particle size and roughness from novel techniques : in situ measurements and validation." Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/17644.
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The roughness of ice crystals, defined by small-scale surface roughness and large scale complexity, in high-altitude cloud, has been studied due to its important influence on the radiative properties of ice cloud. The Small Ice Detector 3 (SID-3) created at the University of Hertfordshire was used to measure the characteristics of individual ice crystals in situ. These are supplemented by a range of meteorological in situ measurements, including temperature, relative humidity, and wind velocity to investigate the influence of atmospheric conditions on ice crystal roughness/complexity. Since the method of roughness retrieval was novel, for atmospheric ice particles, laboratory experiments were setup to test and improve the characterization techniques. Criteria were set as a result of the laboratory experiments which data was expected to meet for it to be deemed reliable. These criteria and techniques were applied to data collected in situ on research aircraft. A range of degrees of ice crystal roughness were observed over five flights from two campaigns based out of Scotland in 2012 and 2015 (PIKNMIX and CIRCCREX). When all the flights were combined the majority of particles (51%) were categorised as lightly rough; the second most common roughness type was moderately rough (39%). Smooth particles made up 10% of the total particles, and < 0.02% were classed as severely rough. When considering a wave-cloud case separately, a similar range of roughness values were seen, however, smooth particles were only observed at the cloud leading-edge where nucleation was expected to occur during the only straight level run of the aircraft to probe this region. During the same wave-cloud flight smooth particles were more common in supersaturated regions and moderately rough crystals were more common in subsaturated regions, suggesting that crystals are more likely to tend towards rougher values when observed in subsaturated environments (a statistical T-test showed this hypothesis to be statistically significant). It was found that due to limitations associated with instantaneous measurements, it was challenging to observe how ice particle roughness evolved in situ, since the history of the individual crystals was unknown in most cases. Orographic cloud, however, was found to provide a more robust estimation of crystal evolution as a consequence of having sharp-leading edges where nucleation events were expected to occur, and since crystals then follow streamlines, the distance from the sharp-leading edge can act as a proxy for time since nucleation.
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Kemalli, Onur. "Measurements Of Velocity Profiles By Using Particle Image Velocimeter." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611068/index.pdf.
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Particle Image Velocimetry (PIV) is an optical technique used to display and evaluate the motion of fine particles in a flow. In this experimental study, velocity profiles are examined by PIV system and basic analysis methods are compared.
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Funes-Gallanzi, Marcelo. "Unsteady flow measurements in air using particle image velocimetry." Thesis, University of Warwick, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307299.
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Sanaye, Sepehr. "Computational aspects of particle image size and velocity measurements." Case Western Reserve University School of Graduate Studies / OhioLINK, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=case1058207972.
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Arellanes, Chuautemoc. "Measurements of reactive oxygen species in the particle phase." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1679290751&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Daniel, Tamar Lynn. "High resolution scattering measurements for stationary particles." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/83787.
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Particle characterization is important to the aerospace field because particle ingestion in propulsion engines can lead to catastrophic failures. It has been shown laser based methodologies can determine size and concentration of spherical particles by using light extinction. However, when one moves to increasingly complex shapes one must take into consideration not only light extinction but multi angle light scattering. Cylindrical particles scatter light in a way that can be quantified by electromagnetic wave theory. This scattering distribution is directly related to the cylinders diameter and material properties, as well as the wavelength of the incident light. This project designed and implemented a rig that measures the scattering distribution of single static cylindrical particles. It was shown that the scattering distribution for cylinders can be measured and compared to computational expected values, especially in the forward scattering region. Future work in measuring the scattering distribution of increasingly complex geometries and in flow conditions is proposed.<br>Master of Engineering
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Brigljević, Vuko. "Measurements of particle - antiparticle oscillations in the Bdo⁻B̄do system /." Zürich, 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13118.
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Meneguz, Elena. "Measurements of the properties of particle segregation in turbulent flows." Thesis, University of Newcastle Upon Tyne, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577190.
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This PhD thesis is devoted to the study of the motion of particles/droplets in turbulent flows with relevance to many industrial and environmental applica- tions. A mathematical model has been built to quantify the clustering or prefer- ential concentration of inertial particles into regions of strain and to gain an insight into the mechanism behind such an inertial process in incompressible turbulent flows. The model uses a powerful technique which is referred to here as the Full Lagrangian Method (FLM). This technique is based upon the calcu- lation of the fractional size of an elemental volume of the particle phase along the trajectory of one single particle from which a second order deformation ten- sor or 'Jacobian' is evaluated: Jij = 8Xi(XO, t)/8xO,j with Xo being the particle position at time t = O. By definition, the instantaneous particle concentration is n(t) = n(O)/IJ(t)1 where J(t) = det(Jij) (Osiptsov 2000). In particular, the study quantifies the maximum amount of preferential con- centration of inertial particles via calculation of the compressibility of the parti- cle suspension and its statistical properties. By exploiting the FLM, it has been possible to identify the existence of singularities in the particle concentration field which would be impossible to detect by conventional box counting tech- niques due to spatial resolution limits. The statistical distribution of these sin- gularities and their frequency is evaluated and clearly has an impact on droplet coalescence and the onset of rain. Lastly, this study is able to capture and estimate the role played by the Random Uncorrelated Motion (RUM) at zero separation and to investigate its relation to the onset of singularities: both effects together with preferential concentration are ultimately responsible for particle collisions.
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Baldi, Sandro. "Energy dissipation measurements in stirred vessels with particle image velocimetry." Thesis, King's College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409634.
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Day, Hugo Alistair. "Measurements and simulations of impedance reduction techniques in particle accelerators." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/measurements-and-simulations-of-impedance-reduction-techniques-in-particle-accelerators(35666138-5941-4c8b-95b3-7beeb3bdfb24).html.
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Wakefields and the corresponding frequency-domain phenomenon beam coupling impedance have been well studied for a number of years as a source of beam instabilities within particle accelerators. With the development of the Large Hadron Collider (LHC) and the large beam currents stored in the LHC during fills for physics production, wakefield driven instabilities and strong beam induced heating have become a limiting factors in luminosity production due to both instantaneous luminousity and the available time for collisions.In this thesis is presented an in depth study of the beam coupling impedance of two important (from an impedance and operational point of view) devices in the LHC; the collimation system and the injection kicker magnets (MKIs). These systems have both been sources of concern for the beam impedance of the LHC, the collimators due to their large transverse impedance and the MKIs due to the strong heating observed during the increased of beam current during operation in 2011 and 2012. The source of the heating for the MKIs is studied in depth, found to be power lost by the beam to wakefields in the MKIs. Simulations and measurements are used to characterise the impedance and localise the areas responsible for the high impedance, here the beam screen and ferrite yoke of the magnet; improvements are proposed to better screen the ferrite yoke and verified. A new RF damping system using ferrite for the collimation system is studied and compared to the existing RF damping system, focusing on the heating of the damping system. Highlights include a new method for measuring the quadrupolar and constant transverse impedances of an asymmetric structure using a coaxial wire technique is proposed and verified using computational simulations, and a study of the heat loss in a ferrite damped cavity, focusing on the location of the power loss for cavities being damped to varying degrees.
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Kail, Norbert. "Quantitative in-situ particle characterization using focused beam reflectance measurements." Düsseldorf VDI-Verl, 2009. http://d-nb.info/993097561/04.
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Hopper, Richard. "Accurate temperature measurements on semiconductor devices." Thesis, De Montfort University, 2010. http://hdl.handle.net/2086/3315.
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Self-heating can have a detrimental effect on the performance and reliability of high power microwave devices. In this work, the thermal performance of the gallium arsenide (GaAs) Gunn diode was studied. Infrared (IR) thermal microscopy was used to measure the peak operating temperature of the graded-gap structured device. Temperature measurements were experimentally validated using micro-thermocouple probing and compared to values obtained from a standard 1D thermal resistance model. Thermal analysis of the conventionally structured Gunn diode was also undertaken using high resolution micro-Raman temperature profiling, IR thermal microscopy and electro/thermal finite element modeling. The accuracy of conventional IR temperature measurements, made on semiconductor devices, was investigated in detail. Significant temperature errors were shown to occur in IR temperature measurements made on IR transparent semiconductors layers and low emissivity/highly reflective metals. A new technique, employing spherical carbon microparticles, was developed to improve the measurement accuracy on such surfaces. The new ‘IR microparticle’ technique can be used with existing IR microscopes and potentially removes the need to coat a device with a high emissivity layer, which causes damage and heat spreading.
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Genc, Ayse Merve. "Power draw measurements as a method of characterization of particle aggregation." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/12672.
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Power consumption is one of the critical parameters in optimization of industrial operations. In the present work, the power draw measurements were used as a method of characterizing and optimizing particle aggregation. A series of agglomerate flotation and oil agglomeration tests were carried out to find a correlation between power draw, particle aggregation and flotation performance.
The experimental program included the agglomerate flotation of a complex nickel sulfide ore with fibrous gangue minerals, oil agglomeration of a fine suspension of bituminous coal used as model systems and oil agglomeration tests on a mixed mineral system with various types of gangue minerals. The effect of the gangue properties on oil agglomeration were studied by changing the coal-to-gangue ratio and the type of the gangue. Power draw measurements were conducted with either a turn-table or an electrical method to characterize and optimize agglomeration.
The results indicate that the system behavior was strongly dependent on the mineralogical composition of the ore. The presence of fibrous gangue minerals in the flotation feed produced by grinding the nickel sulfide ore had a dominating effect on the performance of the flotation process.
Power draw measurements were found to be much more useful in system optimization when compared to the characterization of particle agglomeration. The small portion of nickel sulfide particles in the ore and the complex entangled structure resulting from the presence of large amounts of fibrous gangue minerals probably made the agglomeration process difficult to be followed by power draw measurements. In the case of a simple coal-oil agglomeration system, the power draw measurements were sensitive enough to follow the oil agglomeration process. Concentration (valuable-to-gangue particle ratio), size and shape of these gangue minerals were the factors which affected the system significantly.
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DiSciacca, Jack Michael. "First Single Particle Measurements of the Proton and Antiproton Magnetic Moments." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10951.
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We report a new comparison of the proton (p) and antiproton \((\bar{p})\) magnetic moments. In nuclear magnetons, \(\mu_p/\mu_N\) = 2.792 846 (7) [2.5 ppm], while \(\mu_{\bar{p}}/\mu_N\) = 2.792 845 (12) [4.4 ppm]. The unprecedented accuracy of the antiproton measurement is 680 times more precise than previous work. These first single-particle measurements provide a stringent test of CPT invariance. Our comparison, \(\mu_{\bar{p}}/\mu_p\) = -1.000 000 (5) [5.0 ppm], is consistent with the prediction of the CPT theorem. We also report the observation of a single proton spin flip, opening a path to improved precision by an additional factor of \(10^3\) or \(10^4\).<br>Physics
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Owens, Stephanie Anne. "Advances in measurements of particle cycling and fluxes in the ocean." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79284.
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Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 2013.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>The sinking flux of particles is an important removal mechanism of carbon from the surface ocean as part of the biological pump and can play a role in cycling of other chemical species. This work dealt with improving methods of measuring particle export and measuring export on different scales to assess its spatial variability. First, the assumption of ²³⁸U linearity with salinity, used in the ²³⁸U-²³⁴Th method, was reevaluated using a large sample set over a wide salinity range. Next, neutrally buoyant and surface-tethered sediment traps were compared during a three-year time series in the subtropical Atlantic. This study suggested that previously observed imbalances between carbon stocks and fluxes in this region are not due to undersampling by traps. To assess regional variability of particle export, surface and water-column measurements of ²³⁴Th were combined for the first time to measure fluxes on ~20 km scales. Attempts to relate surface properties to particle export were complicated by the temporal decoupling of production and export. Finally, particle export from ²³⁴Th was measured on transects of the Atlantic Ocean to evaluate basin-scale export variability. High-resolution sampling through the water-column allowed for the identification of unique ²³⁴Th features in the intermediate water column.<br>by Stephanie Anne Owens.<br>Ph.D.
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Mason, Bernard James. "Aerosol cavity ring down spectroscopy : from ensemble to single particle measurements." Thesis, University of Bristol, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.658637.
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Aerosol particles are prevalent in the atmosphere and impact the Earth's energy balance through scattering and absorption of incoming and outgoing radiation. Such particles represent one of the largest uncertainties when trying to characterise the anthropogenic causes in the Earth's changing radiation balance. This thesis describes the development of laboratory based techniques for measuring aerosol optical and microphysical properties that are atmospherically relevant. A single particle trapping technique that uses a Bessel-beam propagating counter to a' gas flow (Bessel-beam/gas-flow) is presented. The changing radius of the trapping particle is determined from the collected elastically scattered light. The fluctuating position of a particle trapped along the Bessel beam length is shown to be directly related to the particle radiation pressure efficiency and thus to its radius and refractive index counter to what is expected from , liquid phase optical chromatography measurements. It is shown that ensemble aerosol particle fractionation using a Bessel-beam/gas-flow instrument is not possible. An aerosol ensemble cavity ring down spectrometer (AE-CRDS) was used to determine the refractive index of hygroscopic sodium nitrate aerosols at different relative humidities, A comparison is made between the refractive index retrieved using AE-CRDS and the refractive index retrieved using a single particle, optical tweezers instrument. The accuracy of the optical tweezers refractive index measurement is found to be significantly higher due to the poorly defined size distribution of the aerosol ensemble in the cavity ring down technique. The development of the single particle cavity ring down spectroscopy (SP-CRDS) technique for highly accurate measurements of aerosol extinction efficiencies is presented. The SP-CRDS instrument uses a Bessel-beam/gas-flow optical trap to control the position of a particle within a cavity ring down spectrometer. A new method of accurately obtaining the real part of the refractive index using this technique is described. Measured extinction efficiencies are compared to Mie simulated extinction efficiencies to obtain the refractive index of single component aerosol particles to an accuracy of better than ± 0.1%.
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Doucet, Daniel Joseph. "Measurements of Air Flow Velocities in Microchannels Using Particle Image Velocimetry." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1333675768.
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Olson, Michael A. "Signal-to-Noise Measurements and Particle Focusing in Liquid-Core Waveguides." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4071.
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This thesis presents an analysis of the signal-to-noise ratio in liquid core anti-resonant reflecting optical waveguides (ARROWs) and the application of hydrodynamic focusing to the waveguides. These concepts are presented as a method to improve the detection capabilities of the ARROW platform. The improvements are specifically targeted at achieving single molecule detection (SMD) with the devices. To analyze the SNR of the waveguides a test platform was designed and fabricated. This test platform was then used to examine relationship between the SNR and the location of the excitation region. It was determined that the excitation region should be moved closer to the solid-core. By moving the excitation region closer to the solid-core the distance the signal was required to travel in the hollow-core was reduced. This reduction led to a decrease in optical signal loss and resulted in a more than 2x increase in the SNR. Hydrodynamic focusing in the waveguides was developed as a method to increase the consistency of detection of the devices. In hydrodynamic focusing particles in the sample are forced towards the center of the waveguide with a buffer solution. With the particles focused to the center of the channel the percentage that passed through the excitation region can be increased improving the detection consistency of the device. ARROW chips designed for hydrodynamic focusing were simulated, fabricated, and preliminary testing was performed. Initial results have shown a more than 30% increase in particle focusing.
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Wright, Matthew Darren. "Submicron particle size distribution and charge state in urban areas using mobility particle sizers : measurements and instrumentation considerations." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544324.
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Yin, Chung-Yuan. "Soot particle size measurements in laminar premixed ethylene flames with laser-induced incandescence and scanning mobility particle sizer." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p1460029.
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Thesis (M.S.)--University of California, San Diego, 2009.<br>Title from first page of PDF file (viewed January 9, 2009). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 46-48).
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Zhu, Weijia. "A new instrumentation for particle velocity and velocity related measurements under water /." View online ; access limited to URI, 2006. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/fullcit/3239913.
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Eidhammer, Trude. "Determining particle index of refraction with measurements of scattering at two angles." Laramie, Wyo. : University of Wyoming, 2006. http://proquest.umi.com/pqdweb?did=1296094721&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Meyer, Jessica [Verfasser]. "Ice Crystal Measurements with the New Particle Spectrometer NIXE-CAPS / Jessica Meyer." Wuppertal : Universitätsbibliothek Wuppertal, 2013. http://d-nb.info/1033621218/34.
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Patchigolla, Kumar. "Particle process measurements : shape and size with crystal growth and nucleation kinetics." Thesis, Heriot-Watt University, 2007. http://hdl.handle.net/10399/2088.
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To deduce particle size information, the majority of particle sizing techniques assume that the particles are spheres. For industrial materials, particles are rarely spherical. Non-sphericity causes discrepancies in different measurement technologies so results vary from the real characteristics of the sample. Applications like crystallisation require .shape information in addition to the size of the particles. The majority of this thesis describes results that have demonstrated that particle shape has a strong influence on particle size distribution measured by different techniques. The effect of shape on measured particle size distribution was investigated by ultrasonic attenuation spectroscopy (VAS) compared with other widely used techniques such as laser diffraction spectroscopy (LDS), microscopic image analysis (MIA) and focused beam reflectance measurement (FBRM). A strategy was applied using different chemical systems to monitor the importance of shape to measured size distribution using different techniques; fragile and non-fragile, .sp-pericaC'crystalline and irregular materials were tested. The measurements were successfully applied to laboratory crystallisation processes of different organic and inorganic chemicals In-situ monitoring of particle size evolution during crystallisation using FBRM has aroused much interest. Therefore it was important to demonstrate the dependence of measured particle size on different operating conditions and more particularly on the hydrodynamic conditions, solvent, temperature and other physical and chemical , properties of the system. In-situ measurement of maximum supersaturation during batch crystallisation and dissolution processes of different chemical systems is presented, through which nucleation kinetics of the crystallisation was retrieved. This was clemonstrated for different organic and inorganic chemical systems using FBRM as a process analytical technique (PAT). Based on crystallisation behaviour and with process analytical techniques, notably FBRM to retrieve the nucleation kinetics, the growth kinetics of different chemical systems are presented based on seeded batch cooling crystallisation. Finally future developments within this area of research are presented.
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Udrea, Doina Daciana. "High accuracy flow velocity measurements using particle image velocimetry : development and applications." Thesis, University of Warwick, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300743.
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Shapley, Nina C. "Laser Doppler velocimetry measurements of particle velocity fluctuations in a concentrated suspension." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/32699.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, February 2000.<br>Includes bibliographical references (p. 246-251).<br>Recent statistical constitutive models of suspensions of neutrally buoyant, non-Brownian, non-colloidal, solid spheres in Newtonian fluids suggest that the particles nijgrate in response to gradients in "suspension temperature," defined as the average kinetic energy contained in the particle velocity fluctuations. These models have not yet been compared systematically with experimental data. In addition, the "temperature" models assume isotropic particle velocity fluctuations, since the "suspension temperature" is given as a scalar, in analogy to molecular systems. However, highly anisotropic particle velocity fluctuations have been observed in settling suspensions, which suggests that a "suspension temperature" tensor would be more realistic. We used laser Doppler velocimetry (LDV) to make a set of experimental observations of particle velocity fluctuations arising from inter-particle collisions in a concentrated non-colloidal suspension under nearly homogeneous shear flow in a narrow-gap concentric cylinder Couette device. We compared the relative sizes of the fluctuating velocity components and observed the variation of each component with particle volume fraction, shear rate, and radial position. In addition, we assessed the implications of these observations for suspension temperature models. The data indicate that the suspension temperature is anisotropic. The flow direction component is overwhelmingly the largest at every concentration and shear rate, followed by the neutral and then the gradient components. Meanwhile, each fluctuating velocity component demonstrates a distinct variation with the shear rate and with the particle volume fraction, but only slight variation with radial position, over the region of the flow accessible to measurement. Comparison between model predictions and measured shear rate and particle volume fraction profiles shows that several models capture the measured profiles qualitatively but not quantitatively, with better agreement for moderately concentrated suspensions than for highly concentrated suspensions. Also, comparison between predicted scalar suspension temperature profiles and the sum of the measured velocity fluctuation components demonstrates that most of the models underpredict the sum of the temperature components by a large factor. Finally, comparison among the models shows that the models are quite sensitive to the choice of transport coefficients that are functions of the particle volume fraction.<br>by Nina Claire Shapley.<br>Ph.D.
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Moon, Chi Young. "Particle Sensing in Gas Turbine Inlets Using Optical Measurements and Machine Learning." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/101969.
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Propulsion systems are exposed to a variety of foreign objects that can significantly damage or
impact their performance. These threats can range from severe dangers such as sandstorms and volcanic eruptions, which can induce engine failure in minutes, to condensation and moisture during ground tests that can negatively impact the engine's fuel efficiency. While numerous computational and experimental studies have investigated the effects of particle ingestion on the component level, an accurate in-situ measurement technique is needed for a systematic understanding of the effects and real-time engine health monitoring.
Optical measurement techniques are attractive for this application due to their non-intrusive
nature. However, conventional optical particle measurement methods assume the particle to be
spherical, which introduces large errors for measuring particles with complex and irregular shapes, such as sand, volcanic ash, and ice crystals. The light-particle interaction contains information on the desired parameters, such as particle shape and size.
The research presented in this dissertation uses this idea for a novel particle sensor concept.
Scattering and extinction of light by particles are chosen as crucial features that can identify the
particle as its unique signature. Numerical tools are used to simulate the scattering and extinction
for particles the sensor is expected to encounter. Machine learning models are trained using the
data to use scattering and extinction as inputs and estimate the particle parameters. Different types and applications of supervised machine learning models were investigated, including a layered approach with numerous models and a generalized approach with a single neural network. The particle sensor is first demonstrated using data found in the literature. This study confirmed the importance of non-spherical particles in the library to guide the machine learning models. Further demonstrations are made at a full engine and wind tunnel scale to measure injected condensation and sand sprays, respectively. The mass flow rates of the ingested material were calculated using the model outputs and validated.<br>Doctor of Philosophy<br>Foreign objects ingested into gas turbines can cause serious damage and degrade their performance. Threats can range from sand, dust, and volcanic ash to condensation on ground and high altitude ice crystals. On the component level, experiments and simulations have been performed to establish the performance decrease and risks to continued operations. However, there is a need for a real-time and non-intrusive measurement technique for the ingested mass. While there are established optical methods applicable for this use, these existing methods assume the particle shape to be spherical. The light-particle interaction contains information on the desired parameters, such as particle shape and size. Optical measurements of these interactions, such as scattering and extinction, can serve as "fingerprints" that can be used to estimate particle parameters.
A novel particle measurement technique utilizing supervised machine learning models is presented. The models are trained using a library containing numerically calculated scattering and extinction data. Laser scattering and extinction measurements are used as inputs for the models. This new technique is first demonstrated by sizing particles found in a particle scattering database in the literature. The method's versatility and ruggedness are then demonstrated by accurately estimating the volume flow rate of a spray nozzle spraying water into a research engine. Additionally, the mass flow of sand particles is measured using this technique in a high-speed wind tunnel, in a similar environment to an engine inlet.
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Bilgen, Suheyla. "Dynamic pressure in particle accelerators : experimental measurements and simulation for the LHC." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASP020.
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L’obtention de très faible pression (UHV) est une condition essentielle pour les accélérateurs de particules de haute énergie et de hautes performances. Par conséquent, la compréhension de l'évolution de la pression dynamique pendant le fonctionnement des accélérateurs est fondamentale afin de trouver des solutions qui permettent de minimiser les hausses de pression induites par de multiples phénomènes présents dans les lignes faisceaux. Pour le LHC, l'apparition d'instabilités peut être due à la succession de plusieurs processus. Tout d’abord, le faisceau de protons de haute intensité ionise le gaz résiduel, produisant des ions positifs (principalement H₂⁺ et CO⁺) ainsi que des électrons qui sont accélérés et qui impactent la paroi en cuivre des tubes de faisceaux. Ensuite, ces interactions induisent : (i) une désorption des gaz absorbés sur les parois, conduisant à des élévations de pression ; (ii) la création de particules secondaires (ions et électrons). Dans ce dernier cas, la production d'électrons secondaires entraîne, par effet d’avalanche, la formation de nuages d’électrons, dont la limitation est l'un des enjeux majeurs de l'anneau de stockage du LHC. Ces nuages génèrent des montées de pression et des dépôts de chaleur sur les parois du collisionneur pouvant conduire à des « quench » d’aimants supraconducteurs. Tous ces phénomènes limitent l'intensité maximale et augmentent l’émittance des faisceaux et donc la luminosité ultime atteignable dans un accélérateur de protons. Ce travail de thèse a pour but d’étudier certains phénomènes fondamentaux qui contrôlent la pression dynamique dans le LHC, à savoir les effets induits par les électrons et les ions, d’une part, et l'influence de la chimie de surface du cuivre constituant les écrans faisceaux, d’autre part. Dans un premier temps, les courants d’électrons et d’ions ainsi que la pression ont été mesurés in situ dans le Secteur Pilote Vide (VPS) situé sur l'anneau du LHC pendant la deuxième période d’exploitation du collisionneur. En analysant ces résultats, une quantité d’ion plus importante que prévu a été détectée et la relation entre les électrons, les ions et les variations de pression a été étudiée. D’autre part, la désorption stimulée par les ions a été mesurée au laboratoire au CERN en utilisant un bâti expérimental dédié. L'influence de la nature, de la masse et de l'énergie des ions incidents interagissant avec les surfaces sur les rendements de désorption ionique a été discutée. De plus, des analyses approfondies de la surface de cuivre constituant l'écran faisceau ont été réalisées dans le laboratoire IJCLab pour identifier le rôle joué par la chimie de surface du cuivre sur le rendement d’émission électronique, les processus de conditionnement de surface et la désorption de gaz stimulée. Le rôle fondamental de composés chimiques sur la surface (contaminants, présence de carbone et d'oxydes natifs) sur le rendement de production des électrons secondaires a été mis en évidence. Enfin, nous avons proposé un code de simulation permettant de prédire les profils de pression dans les chambres à vide des accélérateurs de particules ainsi que leur évolution temporelle. Ce nouveau code de simulation appelé DYVACS (DYnamic VACuum Simulation) est une amélioration du code VASCO développé par le CERN. Il a été appliqué pour simuler la pression dynamique dans le VPS. L'évolution du nuage d'électrons a été implémentée dans le code via des « maps » permettant de calculer l'évolution de la densité des nuages d'électrons. L'ionisation du gaz résiduel par les électrons a également été prise en compte. Finalement, les résultats obtenus avec DYVACS ont été comparés aux mesures de pression enregistrées dans le LHC. Les résultats obtenus à l’issu de ces travaux de thèse, ainsi que les développements expérimentaux et de simulation réalisés, pourront permettre l’étude de la stabilité du vide de futurs accélérateurs de particules tels que HL-LHC ou FCC(ee et hh)<br>Ultra-High Vacuum is an essential requirement to achieve design performances and high luminosities in high-energy particle colliders. Consequently, the understanding of the dynamic pressure evolution during accelerator operation is fundamental to provide solutions to mitigate pressure rises induced by multiple-effects occurring in the vacuum chambers and leading to beam instabilities. For the LHC, the appearance of instabilities may be due to the succession of several phenomena. First, the high intensity proton beams ionize the residual gas producing positive ions (mainly H₂⁺ or CO⁺) as well as accelerated electrons which impinge the copper wall of the beam pipe. Then, these interactions induce: (i) the desorption of gases adsorbed on the surfaces leading to pressure rises; (ii) the creation of secondary particles (ions, electrons). In this latter case, the production of secondary electrons leads to the so-called “Electron Cloud” build-up by multipacting effect, the mitigation of which being one of the major challenges of the LHC storage ring. Electron clouds generate beam instabilities, pressure rises and heat loads on the walls of beam pipe and can lead to “quench” of the superconducting magnets. All these phenomena limit the maximum intensity of the beams and thus the ultimate luminosity achievable in a proton accelerator. This work aims to investigate some fundamental phenomena which drive the dynamic pressure in the LHC, namely the effects induced by electrons and ions interacting with the copper surface of the beam screens on the one hand and the influence of the surface chemistry of copper on the other hand. First, in-situ measurements were performed. Electron and ion currents as well as pressure were recorded in situ in the Vacuum Pilot Sector (VPS) located on the LHC ring during the RUN II. By analyzing the results, more ions than expected were detected and the interplay between electrons, ions and pressure changes was investigated. Then, the ion-stimulated desorption was studied, using a devoted experimental set-up at the CERN vacuum Lab. The influence of the nature, mass, and energy of the incident ions interacting with the copper surface on the ion-desorption yields was discussed. In addition, extensive surface analyses were performed in the IJCLab laboratory to identify the role played by the surface chemistry on the electron emission yield, surface conditioning processes and the stimulated gas desorption. The fundamental role of the surface chemical components (contaminants, presence of carbon and native oxide layers) on the secondary electron yield was evidenced. Finally, we proposed a simulation code allowing to predict the pressure profiles in the vacuum chambers of particle accelerators as well as their evolution under dynamic conditions (i.e. as a function of time). This new simulation code called DYVACS (DYnamic VACuum Simulation) is an upgrade of the VASCO code developed at CERN. It was applied to simulate the dynamic pressure in the VPS when proton beams circulate into the ring. The electron cloud build-up was implemented in the code via electron cloud maps. The ionization of the residual gas by electrons was also considered. Results obtained with the DYVACS code are compared to pressure measurements recorded during typical fills for physics and a good agreement is obtained. This PhD study has provided interesting results and has allowed the development of new experimental and simulation tools that will be useful for further investigations on the vacuum stability of future particle accelerators such as HL-LHC or FCC (ee and hh)
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Shimoda, Tadahiro. "Studies on the Improvement of In-Situ Plasma Particle Measurements in Space." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120666.
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Norris, Sarah Joan. "Sea spray : eddy covariance and near surface measurements of sea spray particles using a novel high-temporal resolution particle spectrometer." Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444043.
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O'Rourke, Abigail. "Measurements of top quark pair production cross-sections with the ATLAS experiment." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/measurements-of-top-quark-pair-production-crosssections-with-the-atlas-experiment(0ffdf00c-7fe4-4b70-bb9a-3106d8dc6aeb).html.
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This thesis presents measurements of inclusive and differential cross-sections for top quark pair-production in fiducial and full phase-space regions, as well as an analysis of gas compositions in the ATLAS inner detector cooling systems. The inclusive top-anti-top quark production cross-section was measured using a sample of 0.085 1/fb of proton--proton collisions recorded by the ATLAS experiment at centre-of-mass energy of 13 TeV, using dilepton top-anti-top quark events with an opposite-sign ee or ÂμÂμ pair in the final state. The numbers of events with exactly one and exactly two jets originating from b-quarks were counted to determine the top-anti-top quark production cross-section . The efficiency to reconstruct and identify a jet as originating from a b-quark from a top quark decay was extracted simultaneously, minimising the associated systematics. The cross-section was measured to be 749 ± 57 (stat.) ± 79 (syst.) ± 74 (lumi.) pb, giving a total relative uncertainty of 16%. The differential top-anti-top quark production production cross-sections were measured using top-anti-top quark events with one electron and one muon of opposite sign electric charge, and at least two jets, one of which was required to be tagged as containing a b-hadron. Initially, the differential cross-sections were measured in a fiducial phase-space region, using an integrated luminosity of 3.2 1/fb of proton--proton data at a centre-of-mass energy of 13 TeV, recorded by the ATLAS experiment in 2015. Subsequently, the single and double differential cross-sections were measured in both a fiducial phase-space region and the full phase-space, using 36.1 1/fb of proton--proton data at 13 TeV, recorded by the ATLAS experiment in 2015 and 2016. The measured differential cross-sections are compared to predictions of next-to-leading order generators matched to parton showers. Custom ultrasonic instruments have been developed for simultaneous monitoring of binary gas mixture and flow in the ATLAS inner detector. These instruments are sensitive to leaks in the cooling systems of the ATLAS inner detector. Software for on- and off-line analysis of these instruments has been developed and proven with the analysis of the cool-down to operation temperature in January 2016.
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Smith, Mark. "Measurements of indirect CP violation in charm at LHCb." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/measurements-of-indirect-cp-violation-in-charm-at-lhcb(aaeb5435-6310-46fa-81b1-6e45fa1af1c0).html.
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This thesis describes two pieces of work. The first is a study of the resolution of the LHCb vertex locator throughout Run 1. The second comprises analyses to measure the charm mixing and CP violation observables A_{Gamma} and y_{CP}.An estimate of the resolution of the LHCb vertex locator is required for use in the track fits. A method to measure the resolution with collision data has been developed and tested. The performance of the sub-detector throughout Run 1 of the LHC has been assessed. A significant degrading of the resolution has been seen. The effects of this on the track reconstruction has been examined with little change in the measured quantities being observed. The measurement of indirect CP violation in neutral D meson transitions has been measured through the observables A_{Gamma} and y_{CP}, using 1fb^{-1} of pp collisions with a centre of mass energy 7TeV, collected by the LHCb detector in 2011.A_{Gamma} describes the CP asymmetry of the lifetime of the D^0 decaying to a CP eigenstate (KK or pipi). The analysis documented here yields A_{Gamma} = (-0.17+-0.54)x10^{-3} when the measurements are combined. This is the world's best measurement and represented a factor of four improvement over the previous best result. The observable y_{CP} compares the effective lifetimes of the Cabibbo favoured decay D^0→Kpi and the transition to a CP eigenstate (KK or pipi). The unblinded result obtained in this document, averaged over both final states is y_{CP} = (5.61+-1.56)x10^{-3}. This result is commensurate with the world average central value within 1.25 standard deviations and has significance of 3.6 standard deviations relative to zero.
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Koch, Bernd. "Angular resolved measurements of particle and energy fluxes to surfaces in magnetized plasmas." Doctoral thesis, [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973051116.
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Wu, Hung-Jen. "Direct measurements of ensemble particle and surface interactions on homogeneous and patterned substrates." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3747.
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In this dissertation, we describe a novel method that we call Diffusing Colloidal
Probe Microscopy (DCPM), which integrates Total Internal Reflection Microscopy
(TIRM) and Video Microscopy (VM) methods to monitor three dimensional trajectories
in colloidal ensembles levitated above macroscopic surfaces. TIRM and VM are well
established optical microscopy techniques for measuring normal and lateral colloidal
excursions near macroscopic planar surfaces. The interactions between particle-particle
and particle-substrate in colloidal interfacial systems are interpreted by statistical
analyses from distributions of colloidal particles; dynamic properties of colloidal
assembly are also determined from particle trajectories.
Our studies show that DCPM is able to detect many particle-surface interactions
simultaneously and provides an ensemble average measurement of particle-surface
interactions on a homogeneous surface to allow direct comparison of distributed and
average properties. A benefit of ensemble averaging of many particles is the diminished
need for time averaging, which can produce orders of magnitude faster measurement
times at higher interfacial particle concentrations. The statistical analyses (Ornstein-
Zernike and three dimensional Monte Carlo analyses) are used to obtain particle-particle
interactions from lateral distribution functions and to understand the role of nonuniformities
in interfacial colloidal systems. An inconsistent finding is the observation of
an anomalous long range particle-particle attraction and recovery of the expected DLVO
particle-wall interactions for all concentrations examined. The possible influence of
charge heterogeneity and particle size polydispersity on measured distribution functions
is discussed in regard to inconsistent particle-wall and particle-particle potentials. In the final part of this research, the ability of DCPM is demonstrated to map potential energy
landscapes on patterned surfaces by monitoring interactions between diffusing colloidal
probes with Au pattern features. Absolute separation is obtained from theoretical fits to
measured potential energy profiles and direct measurement by sticking silica colloids to
Au surfaces via electrophoretic deposition. Initial results indicate that, as colloidal probe
and pattern feature dimensions become comparable, measured potential energy profiles
suffer some distortion due to the increased probability of probes interacting with
surfaces at the edges of adjacent pattern features. Measurements of lateral diffusion via
analysis of mean square displacements also indicated lateral diffusion coefficients in
excellent agreement with rigorous theoretical predictions.
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Chopski, Steven. "PARTICLE IMAGE VELOCIMETRY MEASUREMENTS OF THE TOTAL CAVOPULMONARY CONNECTION WITH CIRCULATORY FLOW AUGMENTATION." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/2096.
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This thesis project examined the interactive fluid dynamics between a blood pump and the univentricular Fontan circulation. 2-D particle image velocimetry (PIV) measurements were conducted on an idealized total cavopulmonary connection (TCPC) with an axial pump prototype in the inferior vena cava (IVC). Fluid velocity profiles were examined under various physiologic conditions for Fontan patients. The velocity profiles for all cases demonstrated the shunting of flow from the IVC toward the right pulmonary artery. A rotational component in the pump outflow was observed forcing flow to the periphery as compared to the flow profile without a pump present in the IVC. The inclusion of the pump provides a pressure rise of 3 to 9 mmHg. These results demonstrate the ability of the intravascular blood pump to support a Fontan circulation and support the continued optimization and development of the pump.
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Bhave, Prakash Viththal Seinfeld John H. "Air pollution at the single-particle level : integrating atmospheric measurements with mathematical models /." Diss., Pasadena, Calif. : California Institute of Technology, 2003. http://resolver.caltech.edu/CaltechETD:etd-05252003-091827.
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Sarra, Angela M. "Particle-wall shear stress measurements within the standpipe of a circulating fluidized bed." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2078.
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Thesis (M.S.)--West Virginia University, 2001.<br>Title from document title page. Document formatted into pages; contains xi, 137 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 136-137).
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Flay, David. "Measurements of the Neutron Longitudinal Spin Asymmetry A1 and Flavor Decomposition in the Valence Quark Region." Diss., Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/286478.
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Physics<br>Ph.D.<br>The current data for the nucleon-virtual photon longitudinal spin asymmetry A1 on the proton and neutron have shown that the ratio of the polarized-to-unpolarized down-quark parton distribution functions, Δ d/d, tends towards -1/2 at large x, in disagreement with the perturbative QCD prediction that Δ d/d approaches 1 but more in line with constituent quark models. As a part of experiment E06-014 in Hall A of Jefferson Lab, double-spin asymmetries were measured in the scattering of a longitudinally polarized electron beam of energies 4.74 and 5.89 GeV from a longitudinally and transversely polarized 3He target in the deep inelastic scattering and resonance region, allowing for the extraction of the neutron asymmetry A1n and the ratios Δ d/d and Δ u/u. We will discuss our analysis of the data and present results for A1 and g1/F1 on both 3He and the neutron, and the resulting quark ratios for the up and down quarks in the kinematic range of 0.2 2 2 for our deep inelastic scattering data. Invoking duality, we also extract A1n and g1n/F1n in the resonance region, characterized by 0.6 2 2. Our measurements are compared to the world data and various theoretical models and more recent predictions using the Dyson-Schwinger Equation approach. We also present analysis of the unpolarized cross section data, which contributes to the g1 spin structure function and eventually the a2 matrix element, an x2-weighted moment of g1. The extracted a2 data are compared to a Lattice QCD calculation.<br>Temple University--Theses
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Meißner, Marco [Verfasser], and Ulrich [Akademischer Betreuer] Uwer. "Measurements of particle production and particle correlations in proton-proton and proton-ion collisions with LHCb / Marco Meißner ; Betreuer: Ulrich Uwer." Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180395409/34.
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Nes, Elena. "Derivation of photon energy spectra from transmission measurements using large fields : a dissertation /." San Antonio : UTHSC, 2006. http://proquest.umi.com/pqdweb?did=1324388751&sid=1&Fmt=2&clientId=70986&RQT=309&VName=PQD.
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Glen, Andrew. "A new optical particle counter for in situ measurements of stratospheric aerosol size distributions." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1400968731&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Manser, John R. "Solid rocket motor plume particle size measurements using multiple optical techniques in a probe." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA296046.
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