Relevant bibliographies by topics / Particles

Academic literature on the topic 'Particles'

Author: Grafiati
Published: 4 June 2021
Last updated: 29 July 2024

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Journal articles on the topic "Particles"

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Zhang, Shangjia, Zhaohuan Zhu, Takahiro Ueda, Akimasa Kataoka, Anibal Sierra, Carlos Carrasco-González, and Enrique Macías. "Porous Dust Particles in Protoplanetary Disks: Application to the HL Tau Disk." Astrophysical Journal 953, no. 1 (August 1, 2023): 96. http://dx.doi.org/10.3847/1538-4357/acdb4e.

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Abstract Dust particle sizes constrained from dust continuum and polarization observations by radio interferometry are inconsistent by at least an order of magnitude. Motivated by porous dust observed in small solar system bodies (e.g., from the Rosetta mission), we explore how the dust particle’s porosity affects the estimated particle sizes from these two methods. Porous particles have lower refractive indices, which affect both opacity and polarization fraction. With weaker Mie interference patterns, the porous particles have lower opacity at millimeter wavelengths than the compact particles if the particle size exceeds several hundred microns. Consequently, the inferred dust mass using porous particles can be up to a factor of six higher. The most significant difference between compact and porous particles is their scattering properties. The porous particles have a wider range of particle sizes with high linear polarization from dust self-scattering, allowing millimeter- to centimeter-sized particles to explain polarization observations. With a Bayesian approach, we use porous particles to fit HL Tau disk’s multiwavelength continuum and millimeter-polarization observations from the Atacama Large Millimeter/submillimeter Array (ALMA) and the Very Large Array (VLA). The moderately porous particles with sizes from 1 mm–1 m can explain both continuum and polarization observations, especially in the region between 20 and 60 au. If the particles in HL Tau are porous, the porosity should be from 70%–97% from current polarization observations. We also predict that future observations of the self-scattering linear polarization at longer wavelengths (e.g., ALMA B1 and ngVLA) have the potential to further constrain the particle’s porosity and size.
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Zhao, Zhen Kai, Yan Pei Song, and Zhi Ming Feng. "Study on the Migration Law of Unmelted WC Particles during the Process of Centrifugal Casting." Advanced Materials Research 320 (August 2011): 394–98. http://dx.doi.org/10.4028/www.scientific.net/amr.320.394.

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A model of the movement of WC reinforcing particles with the effect of centrifugal force during the process of centrifugal casting was established. The motion equations of the WC particles were solved in this model. The motion curve of the WC particles WC particle was drawn according to the motion equation, and the influential factors of WC particle's movement are analyzed. The conclusions show that: the radical movement speed of the WC particles increases with the increase of time, and the movement distance increases by exponentially at the same time. The particle movement distance at the same time increases due to the larger diameter, the quicker centrifugal speed and the higher the casting temperature. The radial pitch of the particle with different initial position becomes lager with the increase of time. Centrifugal Casting formed the final particle reinforced composites, in which the volume fraction of WC particles gradient increased from the inner surface to the outer surface.
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Li, Xiang, and Ying Lin. "Fluid-Structure Interaction Approach to Single Particle in a Square Microchannel." Journal of Physics: Conference Series 2097, no. 1 (November 1, 2021): 012002. http://dx.doi.org/10.1088/1742-6596/2097/1/012002.

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Abstract Inertial microfluidic technique has been widely applied on particle/cell manipulation and detection. To understand the physical principle of this technique more detailed, the interaction of fluid and particle was studied through the Fluid-Structure Interaction (FSI) method. The equilibrium positions of finite-size particles with different diameters were simulated at moderate Reynolds numbers. The flow structure around two typical particles was analysed. The vortex in the front of the particle retards particle’s translation leading to the lag velocity increasing. Finally, the rotation velocity and the rotational-induced force analysed quantitatively to demonstrate that particle’s self-rotation significantly promotes its inertial migration.
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Ohshima, Hiroyuki. "Diffusiophoresis of a Soft Particle as a Model for Biological Cells." Colloids and Interfaces 6, no. 2 (April 14, 2022): 24. http://dx.doi.org/10.3390/colloids6020024.

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We derive the general expression for the diffusiophoretic mobility of a soft particle (i.e., polyelectrolyte-coated hard particle) in a concentration gradient of electrolytes for the case in which the particle’s core size is large enough compared with the Debye length. Therefore, the particle surface can be regarded as planar, and the electrolyte concentration gradient is parallel to the core surface. The obtained expression can be applied for arbitrary values of the fixed charge density of the polyelectrolyte layer and the surface charge density of the particle core. We derive approximate analytic mobility expressions for soft particles of three types, i.e., (i) weakly charged soft particles, (ii) soft particles with a thick polyelectrolyte layer, in which the equilibrium electric potential deep inside the polyelectrolyte layer is equal to the Donnan potential, and (iii) soft particles with an uncharged polymer layer of finite thickness.
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DiBenedetto, Michelle H., Nicholas T. Ouellette, and Jeffrey R. Koseff. "Transport of anisotropic particles under waves." Journal of Fluid Mechanics 837 (December 21, 2017): 320–40. http://dx.doi.org/10.1017/jfm.2017.853.

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Using a numerical model, we analyse the effects of shape on both the orientation and transport of anisotropic particles in wavy flows. The particles are idealized as prolate and oblate spheroids, and we consider the regime of small Stokes and particle Reynolds numbers. We find that the particles preferentially align into the shear plane with a mean orientation that is solely a function of their aspect ratio. This alignment, however, differs from the Jeffery orbits that occur in the residual shear flow (that is, the Stokes drift velocity field) in the absence of waves. Since the drag on an anisotropic particle depends on its alignment with the flow, this preferred orientation determines the effective drag on the particles, which in turn impacts their net downstream transport. We also find that the rate of alignment of the particles is not constant and depends strongly on their initial orientation; thus, variations in initial particle orientation result in dispersion of anisotropic-particle plumes. We show that this dispersion is a function of the particle’s eccentricity and the ratio of the settling and wave time scales. Due to this preferential alignment, we find that a plume of anisotropic particles in waves is on average transported farther but dispersed less than it would be if the particles were randomly oriented. Our results demonstrate that accurate prediction of the transport of anisotropic particles in wavy environments, such as microplastic particles in the ocean, requires the consideration of these preferential alignment effects.
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Yu, Chengcheng, and Laijun Zhao. "Multi-Objective Particle Swarm Optimization Algorithm based on Position Vector Offset." International Journal of Mechanical and Electrical Engineering 2, no. 2 (April 15, 2024): 131–35. http://dx.doi.org/10.62051/ijmee.v2n2.15.

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In response to the issue that particle swarm optimization algorithms tend to fall into local optima when dealing with multi-objective optimization tasks, a multi-objective optimization algorithm based on particle swarm is proposed. This algorithm is based on the relationship between the position vectors of particles, changing the selection and movement strategies of particles to find the true Pareto front. Firstly, two additional position vectors are added around the iterating particles to enhance their search capability; then, a non-dominated vector archive is established to record the non-dominated solutions of the iterating particles and the additional position vectors, increasing particle diversity. Finally, additional position vectors with high fitness are selected to produce a shift in the iterating particle's position, accelerating particle convergence. Comparing this algorithm with dMOPSO, SMPSO, NMPSO, and MOPSOCD algorithms, simulation experiments show that the proposed PVSPSO algorithm has stronger optimization ability.
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Crutcher, Russ. "Scotch® Magic Tape™ and the Analysis of Settled Dust." Microscope 70, no. 4 (2023): 177–83. http://dx.doi.org/10.59082/akyo4067.

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An environmental “sticky” tape lift contains hundreds to tens of thousands of individual particles. Each particle is unique, and its optical properties indicate the particle’s identity and history. Environmental particles are not isolated and by association occur with other particles, which may provide information on the source of an individual particle. The physical placement of particles on a surface carries information about the individual particles as well as the microenvironment associated with the surface at that location. Sampling is a destructive process because information is lost no matter how the surface is sampled. Therefore, the chosen sampling procedure must retain the data required for the analysis. Tape lifts can retain data on particle concentrations, particle identification, particle sources, transport mechanisms active at the sample location, and more. The type and quality of tape, how it is processed, and how it is analyzed will affect the extent to which the environment has been characterized. 3M Scotch® Magic™ Tape (Magic Tape) and the light microscope have been used to make tape lifts by the author since 1970 for characterizing environments. The advantages and disadvantages of using this sampling method are briefly discussed.
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Liu, Yanmin, and Ben Niu. "A Novel PSO Model Based on Simulating Human Social Communication Behavior." Discrete Dynamics in Nature and Society 2012 (2012): 1–21. http://dx.doi.org/10.1155/2012/791373.

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In order to solve the complicated multimodal problems, this paper presents a variant of particle swarm optimizer (PSO) based on the simulation of the human social communication behavior (HSCPSO). In HSCPSO, each particle initially joins a default number of social circles (SC) that consist of some particles, and its learning exemplars include three parts, namely, its own best experience, the experience of the best performing particle in all SCs, and the experiences of the particles of all SCs it is a member of. The learning strategy takes full advantage of the excellent information of each particle to improve the diversity of the swarm to discourage premature convergence. To weight the effects of the particles on the SCs, the worst performing particles will join more SCs to learn from other particles and the best performing particles will leave SCs to reduce their strong influence on other members. Additionally, to insure the effectiveness of solving multimodal problems, the novel parallel hybrid mutation is proposed to improve the particle’s ability to escape from the local optima. Experiments were conducted on a set of classical benchmark functions, and the results demonstrate the good performance of HSCPSO in escaping from the local optima and solving the complex multimodal problems compared with the other PSO variants.
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Yu, Chi, Runhui Geng, and Xinwen Wang. "A Numerical Study of Separation Performance of Vibrating Flip-Flow Screens for Cohesive Particles." Minerals 11, no. 6 (June 14, 2021): 631. http://dx.doi.org/10.3390/min11060631.

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Vibrating flip-flow screens (VFFS) are widely used to separate high-viscosity and fine materials. The most remarkable characteristic is that the vibration intensity of the screen frame is only 2–3 g (g represents the gravitational acceleration), while the vibration intensity of the screen surface can reach 30–50 g. This effectively solves the problem of the blocking screen aperture in the screening process of moist particles. In this paper, the approximate state of motion of the sieve mat is realized by setting the discrete rigid motion at multiple points on the elastic sieve mat of the VFFS. The effects of surface energy levels between particles separated via screening performance were compared and analyzed. The results show that the flow characteristics of particles have a great influence on the separation performance. For 8 mm particle screening, the particle’s velocity dominates its movement and screening behavior in the range of 0–8 J/m2 surface energy. In the feeding end region (Sections 1 and 2), with the increase in the surface energy, the particle’s velocity decreases, and the contact time between the particles and the screen surface increases, and so the passage increases. When the surface energy level continues to increase, the particles agglomerate together due to the effect of the cohesive force, and the effect of the particle’s agglomeration is greater than the particle velocity. Due to the agglomeration of particles, the difficulty of particles passing through the screen increases, and the yields of various size fractions in the feeding end decrease to some extent. In the transporting process, the agglomerated particles need to travel a certain distance before depolymerization, and the stronger the adhesive force between particles, the larger the depolymerization distance. Therefore, for the case of higher surface energy, the screening percentage near the discharging end (Sections 3 and 4) is greater. The above research is helpful to better understand and optimize the screening process of VFFS.
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Tiwari, Aishwarya. "Calculations of the Average Number of Radicals per Particle in Emulsion Polymerization." International Journal for Research in Applied Science and Engineering Technology 9, no. VI (June 15, 2021): 1056–59. http://dx.doi.org/10.22214/ijraset.2021.35189.

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In emulsion polymerization, the free radicals enter the particles intermittently from the aqueous phase. The number of radicals per particleis given by the Smith-Ewart recursion relation which balances the rate of radical entry into, the rate of radical exit from and the rate of radical termination inside the particle. Models for emulsion polymerisation are based on the 0-1 kinetics or the pseudo-bulk kinetics. Small particles, low initiator concentrations and large number of particles favour the 0–1 kinetics, whereas the large particles, high initiator concentrations and small number of particles will favour pseudo-bulk kinetics. A given polymerization system may exhibit both these kinetic behaviours, initially following the 0-1 kinetics and during the later stages of polymerization following the pseudo-bulk kinetics. The aim of this work is to calculate the time dependent values of the average number of radicals per particle in emulsion polymerization for the pseudo-bulk kinetics.
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Dissertations / Theses on the topic "Particles"

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Mönckedieck, Mathias [Verfasser]. "Particle-particle interactions between tailored mannitol carrier particles and drug particles for inhalation / Mathias Mönckedieck." Kiel : Universitätsbibliothek Kiel, 2016. http://d-nb.info/1118500180/34.

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Ko, Lawrence Ching Leung. "Particle stimulated nucleation : deformation around particles." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/particle-stimulated-nucleation-deformation-around-particles(723ed7d0-21ea-43d5-bba7-22dab5226668).html.

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Second phase particles play an important role in the recrystallization of aluminium alloys. They give rise to high level of local lattice misorientation around the particle, in particle deformation zone (PDZ) during processing. These can act as potent nucleation sites for new recrystallized grains in a process known as particle stimulated nucleation (PSN). This mechanism is essential to produce material with a more random texture and small grain size, which helps e.g. ductility and formability. A new HRDIC technique is used here in combination with EBSD to investigate the evolution of deformation structures by linking the local deformation (by Digital Image Correlation, DIC) to the lattice orientation before and after deformation by EBSD measurements and compared with the CPFEM predictions. The results show that strain is very heterogeneous during deformation and concentrates mainly in slip bands. The spacing between these bands is affected by several factors: applied strain, crystallographic orientation and the existence of small dispersoids. Thus, the relationship between the strain, particle size and rotation in the deformation zone is much more complex than predicted by existing models.
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Petrosky, Brian Joseph. "Particle Image Velocimetry Applications of Fluorescent Dye-Doped Particles." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52983.

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Laser flare can often be a major issue in particle image velocimetry (PIV) involving solid boundaries in a flow or a gas-liquid interface. The use of fluorescent light from dye-doped particles has been demonstrated in water applications, but reproducing the technique in an airflow is more difficult due to particle size constraints and safety concerns. The following thesis is formatted in a hybrid manuscript style, including a full paper presenting the applications of fluorescent Kiton Red 620 (KR620)-doped polystyrene latex microspheres in PIV. These particles used are small and monodisperse, with a mean diameter of 0.87 μm. The KR620 dye exhibits much lower toxicity than other common fluorescent dyes, and would be safe to use in large flow facilities. The first sections present a general introduction followed by a validation experiment using a standard PIV setup in a free jet. This work was the first to demonstrate PIV using fluorescent KR620-doped microspheres in an airflow, and results from the experiment were compared to similar data taken using standard PIV techniques. For the free jet results, Mie-scattered and fluorescent PIV were compared and showed average velocities within 3% of each other at the nozzle exit. Based on the PIV validation requirements used, this was deemed to be more of an indication of nozzle unsteadiness rather than an error or bias in the data. Furthermore, fluorescent PIV data obtained vector validation rates over 98%, well above the standard threshold of 95%. The journal article expands on the introductory work and analyzes testing scenarios where fluorescent PIV allows for velocity measurements much closer to a solid surface than standard, Mie-scattered PIV. The fluorescent signal from the particles is measured on average to be 320 ± 10 times weaker than the Mie scattering signal from the particles. This fluorescence-to-Mie ratio was found to be nonuniform, with the typical signal ratio for a single particle expected to fall between 120 and 870. This reduction in signal is counterbalanced by greatly enhanced contrast via optical rejection of the incident laser wavelength. Fluorescent PIV with these particles is shown to eliminate laser flare near surfaces, in one case leading to 63 times fewer spurious velocity vectors than an optimized Mie scattering implementation in a region more than 5 mm from an angled surface. In the appendix, a brief summary of an experiment to characterize the temperature sensitivity of the KR620 dye is included. This experiment concluded that the KR620 particles did not exhibit sufficient temperature sensitivity to warrant further investigation at the time.
Master of Science
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Boskovic, Lucija. "Influence of Submicron Particle Shape on Behaviour during Filtration and Separation Processes." Thesis, Griffith University, 2008. http://hdl.handle.net/10072/366111.

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Filtration is the most efficient method of aerosol monitoring and control. A number of theories (Bradley, 1932); (Hamaker, 1937); (Johnson et al., 1971); (Wang and Kasper, 1991); (Dahneke, 1995); (Wall et al., 1990) have been developed to describe the particle interaction with surface of a filter and to estimate the probability of the particle adhesion onto a surface. A range of the particle, filter and process parameters could contribute to the strength of the adhesion. Some of them are: hardness and cross-sectional shape of the fiber, smoothness of either the fiber or particle, air humidity, the effect of particle shape and many others. Obviously, the particle size (and correspondingly the surface area) also plays a crucial role in the bouncing processes. However, despite its importance in the research field the detailed mechanisms of the particle-fiber collision and possibility for the particle to bounce or to be re-entrained have not been fully explored. Therefore, there is a need for a theoretical and experimental knowledge concerning the influence of particle bouncing on filtration and separation processes. Although, some work on the effect of particle shape on filtration process has been done, there is still need for further research regarding the influence of motion of the particles of different shape along a fiber...
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Engineering
Science, Environment, Engineering and Technology
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Deng, Mao [Verfasser]. "Micro-Structure of Functional Particles and Particle Systems / Mao Deng." Kiel : Universitätsbibliothek Kiel, 2015. http://d-nb.info/1073868400/34.

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Zawadowicz, Maria Anna. "Understanding the chemistry of atmospheric particles using single particle mass spectrometry." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113793.

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Thesis: Ph. D. in Atmospheric Chemistry, Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 197-219).
This thesis explores ways in which single particle mass spectrometry can be extended, whether through hardware improvements, or through the use of advanced data processing techniques to provide new kinds of aerosol chemistry measurements. Most of this work has been carried out using the Particle Analysis by Laser Mass Spectrometry (PALMS) instrument, an aircraft deployable mass spectrometer that uses intense (~10 9 Wcm -2 ) UV laser pulses to vaporize and ionize single particles and measures their mass spectra using a time-of-flight mass spectrometer. Near-term and long-term hardware improvements as well as advanced data analysis techniques are explored in order to extract new chemical information from the thus obtained single particle mass spectra. Hardware improvements to PALMS are explored, such as the use of a high-powered femtosecond laser to obtain single particle mass spectra and a new high resolution compact mass analyzer. Also, a new commercial mass spectrometer LAAPToF is characterized and compared to PALMS. In addition to hardware improvements, novel data analysis techniques for analysis of single particle mass spectra were developed as a part of this work. In particular, a new method to identify biologically-derived particles is presented and used to derive vertical profiles of bioaerosol from near-surface to the upper troposphere.
by Maria Anna Zawadowicz.
Ph. D. in Atmospheric Chemistry
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Dikken, Marcel den. "Particles : on the syntax of verb-particle, triadic, and causative constructions /." New York : Oxford university press, 1995. http://catalogue.bnf.fr/ark:/12148/cb412247666.

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Swartzel, Jeffrey M. "Rolling of an Elliptic-Shaped Particle in Two Dimensions: A Mathematical Model." Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1240522472.

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Thesis (M.S.)--University of Akron, Dept. of Mathematics, 2009.
"May, 2009." Title from electronic thesis title page (viewed 7/28/2009) Advisor, Dmitry Golovaty; Faculty Readers, Gerald Young, Patrick Wilber; Department Chair, Joseph Wilder; Dean of the College, Chand Midha; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
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Elhimer, Medhi. "The dynamics of neutrally buoyant particles in isotropic turbulence : an experimental study." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0049/document.

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Le but de cette étude expérimentale est de caractériser la dynamique de particules solides, à flottabilité nulle, incluse dans un écoulement turbulent isotrope en décroissance libre. Les particules utilisées sont de forme sphérique et ont un diamètre de 4 à 5 fois plus grand que l'échelle spatial de Kolmogorov de l'écoulement. De part leur taille, les particules ont également un nombre de Stokes proche de l'unité. On s'attend alors à ce que ces particules aient une dynamique différente de celle du fluide environnant. Dans cette étude, ont se propose de quantifier les différences de vitesses entre les deux phases à l'aide d'une technique de vélocimétrie simultanée
In this experimental study, the focus is made on the characterization of the dynamics of solid neutrally buoyant particles embedded in a freely decaying, nearly isotropic turbulence, with a weak mean flow. The particles are spherical with diameters several times larger than the Kolmogorov scale. The study of this flow configuration is still challenging both theoretically and numerically. Due to large particle sizes, the local flow around particles can not be considered as uniform and due to fluid-particle density ratio of around unity, the history and Basset forces cannot be neglected in comparison with the viscous drag force. Particle equation of motion is then fully non-linear, in contrast to the equation for heavy particles with diameters smaller then the Kolmogorov scale, for which only the Stokes drag is considered. In several experimental and numerical studies, the effect of particle size on velocity and acceleration statistics has been investigated (Homann and Bec 2010 ; Qureshi et al. 2008 ; Ouellette et al. 2008 ; Xu and Bodenschatz 2008). In the case of isotropic turbulence, Homann and Bec (2010) show that while the PDF of the particle velocity normalized by the square root of its variance does not vary with particle size, the variance itself is size dependent. A scaling relation for particle velocity variance has been proposed by using the Faxen correction (Gatignol 1983) which takes into account the non uniformity of the fluid flow at the scale of the particle. The aim of our research is to further study the dependence of particle dynamics on particle size. To that purpose, a turbulence generator has been set-up and the resulting turbulence is characterized. Then the flow was seeded with millimeter sized, neutrally-buoyant particles and the velocity of the two phases have been measured simultaneously. Simultaneous measurements of particle and surrounding fluid velocities show that although the global velocity statistics of the two phases have comparable values, the particles may have different local velocity from the velocity of the neighboring fluid
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Dupont, Frédéric. "Mesure de durées de vie des hadrons beaux neutres et chargés avec le canal B-J/(psi)X, et J/(psi)-(mu)+(mu)- dans l'expérience DELPHI (LEP)." Université Joseph Fourier (Grenoble ; 1971-2015), 1994. http://www.theses.fr/1994GRE10057.

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Afin de mesurer les durees de vie separees des hadrons beaux neutres et charges, les donnees enregistrees en 1991 et 1992 par le detecteur delphi du lep ont ete analysees. Les hadrons b sont identifies par leur desintegration en j psi, suivi de la desintegration de celui-ci en une paire de muons. Les performances du detecteur permettent de reconstruire avec precision les longueurs de vol des b dans le plan r phi, de meme que leur impulsion par une technique de regroupement de particules en jet, dont le j psi constitue le noyau. Le temps propre est ainsi determine evenement par evenement. L'estimation de la charge des hadrons b repose sur une methode de discrimination entre les particules qu'ils ont generees et celles provenant du processus de fragmentation. Apres selection, 80 evenements permettent de mesurer une duree de vie de 1,20 ps pour les hadrons b neutres et de 1,80 ps pour les b charges, avec une erreur de 0,40 ps dans les deux cas
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Books on the topic "Particles"

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Perez, Rolando. Particles. Alexandria, VA: Alexander Street Press, 2005.

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Borne, Emmanuelle. Particules élémentaires: Françoise Raynaud, Loci Anima = Elementary particles. Paris: Archipress & associés, 2020.

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library, Wiley online, ed. Elementary particle physics: Quantum field theory and particles. Weinheim: Wiley-VCH, 2010.

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Weinberg, Steven. The discovery of subatomic particles. London: Penguin, 1993.

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A, Mehlhorn Thomas, and Sweeney Mary Ann 1945-, eds. BEAMS 2002: 14th International Conference on High-Power Particle Beams, Albuquerque, New Mexico, 23-28 June 2002. Melville, N.Y: American Institute of Physics, 2002.

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Okubo, Masayoshi. Polymer particles. Berlin: Springer, 2011.

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Masayoshi, Okubo, ed. Polymer particles. Berlin: Springer, 2005.

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Bayer, Josef, and Volker Struckmeier, eds. Discourse Particles. Berlin, Boston: De Gruyter, 2016. http://dx.doi.org/10.1515/9783110497151.

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Hancil, Sylvie, Alexander Haselow, and Margje Post, eds. Final Particles. Berlin, München, Boston: DE GRUYTER, 2015. http://dx.doi.org/10.1515/9783110375572.

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Abraham, Werner, ed. Discourse Particles. Amsterdam: John Benjamins Publishing Company, 1991. http://dx.doi.org/10.1075/pbns.12.

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Book chapters on the topic "Particles"

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Koskinen, Hannu E. J., and Emilia K. J. Kilpua. "From Charged Particles to Plasma Physics." In Astronomy and Astrophysics Library, 63–83. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-82167-8_3.

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AbstractIn this chapter we move from single particle motion to the statistical description of a large number of charged particles, the plasma. This discussion provides the basis for the rich flora of plasma waves that are essential for understanding the sources and losses of radiation belt particles through wave–particle interactions.
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Schröder, Christina, Xingwen Wei, Undine Fischer, Gert Schmidt, Olena Volkova, and Christos G. Aneziris. "In Situ Observation of Collision Between Exogenous and Endogenous Inclusions on Steel Melts for Active Steel Filtration." In Multifunctional Ceramic Filter Systems for Metal Melt Filtration, 27–55. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-40930-1_2.

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AbstractInvestigations at the high-temperature confocal laser scanning microscope (HT-CLSM) allow observing the interaction of non-metallic particles in terms of potential filter material with endogenous particles of molten steel in the high-temperature range. The respective particle velocities are determined from the particle movements and conclusions are drawn about the attractive forces of the particles. The interactions of exogenous Al2O3 particles, MgO and MgAl2O4 spinel particles, and CA6 calcium aluminate particles with endogenous constituents of molten steel X15CrNiSi25-20 are analyzed in the present work. Accompanying experiments were performed in a heating microscope on the interaction between steel and MgO and steel and CA6. Scanning electron microscopy SEM/EDX/EBSD studies reveal not only the interactions of the non-metallic inclusions with each other, but also reactions of the molten steel with the exogenous particles that affect the agglomeration behavior. While exogenous and endogenous Al2O3 particles exhibit high attractive forces and almost no react with the molten steel, a liquid reaction layer forms around the magnesia particles, which leads to a reduction of the attractive forces. After dissolution of the reaction layer, the attractive forces increase. Spinel particles are surrounded by a strong meniscus in the observed steel melt. Endogenous particles moving toward the spinel do not adhere to the particle. Reactions were also observed when CA6 particles came into contact with molten steel. In this process, the calcium aluminate is depleted of calcium. Only loose connections of the exogenous Ca-depleted CA6 with endogenous Al2O3 particles have been detected.
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Capellman, Jarred, and Louis Salin. "Particles." In MonoGame Mastery, 147–90. Berkeley, CA: Apress, 2020. http://dx.doi.org/10.1007/978-1-4842-6309-9_8.

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Nomura, Yasunori, Bill Poirier, and John Terning. "Particles." In Quantum Physics, Mini Black Holes, and the Multiverse, 81–93. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-41709-7_7.

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Horvath, Helmuth. "Particles." In Urban Air Pollution — European Aspects, 161–73. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-015-9080-8_9.

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Ben, Rogers. "Particles." In The Big Ideas in Physics and How to Teach Them, 87–105. Abingdon, Oxon: Routledge, 2018.: Routledge, 2018. http://dx.doi.org/10.4324/9781315305431-6.

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Broekman, Jan M. "Particles." In Meaning, Narrativity, and the Real, 151–201. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-28175-9_4.

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Allday, Jonathan. "Particles." In Quantum Reality, 23–34. 2nd ed. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003225997-4.

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Kahn, Lily, and Riitta-Liisa Valijärvi. "Particles." In West Greenlandic, 293–96. London: Routledge, 2021. http://dx.doi.org/10.4324/9781315160863-12.

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Roda, Chris. "Particles." In Real Time Visual Effects for the Technical Artist, 325–72. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003009795-8.

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Conference papers on the topic "Particles"

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Zhou, Zeyu, and Bruce Hajek. "Particle Thompson Sampling with Static Particles." In 2023 57th Annual Conference on Information Sciences and Systems (CISS). IEEE, 2023. http://dx.doi.org/10.1109/ciss56502.2023.10089653.

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Aubry, Nadine, and Pushpendra Singh. "Electrostatic Forces on Particles Floating Within the Interface Between Two Immiscible Fluids." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-44095.

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The objective of this paper is to study the dependence of the electrostatic force that act on a particle within the interface between two immiscible fluids on the parameters such as the dielectric properties of the fluids and particles, the particle’s position within the interface, and the electric field strength. It is shown that the component of electrostatic force normal to the interface varies as a2, where a is the particle radius, and since in equilibrium it is balanced by the vertical capillary force, the interfacial deformation caused by the particle changes when an external electric field is applied. In addition, there are lateral electrostatic forces among the particles due to the dipole-dipole interactions which, when the distance between two particles is O(a), vary as a2, and remain significant for submicron sized particles.
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Fischbach, Fritz A. "Oriented and disoriented microparticle radii of gyration in the Fraunhofer-dominated regime." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.fp5.

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A radius of gyration is a particle parameter obtainable through light- or x-ray scattering in the Rayleigh-Gans-Debye regime. Radii of gyration can also be theoretically defined and experimentally obtained for scattering in the Fraunhofer diffraction dominated regime. It is shown how this applies to both oriented and disoriented scattering for particles of general shape. For oriented particles, the parameter is the root-mean-square distance from a line passing through the particle's center of mass, along the direction of intensity scanned in the plane perpendicular to the incident radiation beam direction. For disoriented particles, any scanning direction in this plane will give a root-mean-square distance from the particle's center of mass. In both cases the particle is represented as a flat mask outline. Experimental procedures and particle properties necessary for obtaining the parameters are outlined. A simple laser procedure applicable at least to many particles in the 10-μm to 100-μm size range is described.
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Jubery, Talukder Z., Shiv G. Kapoor, and John E. Wentz. "Effect of Inter-Particle Interaction on Particle Deposition in a Cross-Flow Microfilter." In ASME 2013 International Manufacturing Science and Engineering Conference collocated with the 41st North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/msec2013-1211.

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Recent studies show that inter-particle interaction can affect particle trajectories and particle deposition causing fouling in the microfilters used for metal working fluids (MWFs). Inter-particle interaction depends on various factors: particle geometry and surface properties, membrane pore geometry and surface properties, MWF’s properties and system operating conditions, etc. A mathematical model with a Langevin equation for particle trajectory and a hard sphere model for particle deposition has been used to study the effect of particle’s size, particle’s surface zeta potential, inter-particle distance, and shape of membrane pore wall surface on particle trajectory and its deposition on membrane pore wall. The study reveals that bigger particles have a lesser tendency to be deposited on membrane pore walls than smaller particles. The shape of the membrane pore wall surface can also affect the particle deposition behavior.
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Closas, Pau, and Carles Fernandez-Prades. "Particle filtering with adaptive number of particles." In 2011 IEEE Aerospace Conference. IEEE, 2011. http://dx.doi.org/10.1109/aero.2011.5747439.

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Zhou, Zeyu, and Bruce Hajek. "Improving Particle Thompson Sampling through Regenerative Particles." In 2023 57th Annual Conference on Information Sciences and Systems (CISS). IEEE, 2023. http://dx.doi.org/10.1109/ciss56502.2023.10089647.

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Quintana, Boris. "Particle identification of neutral particles at LHCb." In Sixth Annual Conference on Large Hadron Collider Physics. Trieste, Italy: Sissa Medialab, 2018. http://dx.doi.org/10.22323/1.321.0046.

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Coates, M., and G. Ing. "Sensor network particle filters: motes as particles." In 2005 Microwave Electronics: Measurements, Identification, Applications. IEEE, 2005. http://dx.doi.org/10.1109/ssp.2005.1628769.

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Barone, Dominic L., Jane Hawkins, Eric Loth, and Philip H. Snyder. "Inertial Particle Separator Efficiency Using Spherical Particles." In 49th AIAA/ASME/SAE/ASEE Joint Propulsion Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2013. http://dx.doi.org/10.2514/6.2013-3666.

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Keith, David W., and Herbert J. Bernstein. "Two-particle correlation experiments with massive particles." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.fh2.

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Since the first observation of two-point correlation effects in optical fields (Hanbury, Brown, and Twiss, 1957) there has been continuous theoretical and experimental interest in photon correlation. In this paper we examine the possibility of measuring similar effects involving massive particles. We first discuss the theory of correlations between noninteracting massive particles by using the formalism of second quantization. This theory is considerably simpler than that for light because we can treat particles in the strictly nonrelativistic limit. However, the theory provides a particularly interesting contrast with the photon case because we may choose particles that are either fermions or bosons. We then apply the theory to the case of beams of atoms and neutrons and consider the experimental parameters of existing beams. In particular, we consider the case of experiments with laser-cooled metastable helium.
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Reports on the topic "Particles"

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Bigl, Matthew, Samuel Beal, and Charles Ramsey. Determination of residual low-order detonation particle characteristics from Composition B mortar rounds. Engineer Research and Development Center (U.S.), August 2022. http://dx.doi.org/10.21079/11681/45260.

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Empirical measurements of the spatial distribution, particle-size distribution, mass, morphology, and energetic composition of particles from low-order (LO) detonations are critical to accurately characterizing environ-mental impacts on military training ranges. This study demonstrated a method of generating and characterizing LO-detonation particles, previously applied to insensitive munitions, to 81 mm mortar rounds containing the conventional explosive formulation Composition B. The three sampled rounds had estimated detonation efficiencies ranging from 64% to 82% as measured by sampled residual energetic material. For all sampled rounds, energetic deposition rates were highest closer to the point of detonation; however, the mass per radial meter varied. The majority of particles (>60%), by mass, were <2 mm in size. However, the spatial distribution of the <2 mm particles from the point of detonation varied be-tween the three sampled rounds. In addition to the particle-size-distribution results, several method performance observations were made, including command-detonation configurations, sampling quality control, particle-shape influence on laser-diffraction particle-size analysis (LD-PSA), and energetic purity trends. Overall, this study demonstrated the successful characterization of Composition B LO-detonation particles from command detonation through combined analysis by LD-PSA and sieving.
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Ali, Usman, Mamoru Kikumoto, Matteo Ciantia, and Ying Cui. Direct observation of particle kinematics in biaxial shearing test. University of Dundee, December 2021. http://dx.doi.org/10.20933/100001233.

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Biaxial shearing tests on dual-sized, 2d particle assemblies are conducted at several confining pressures. The effect of particle angularity, an important mesoscale shape descriptor, is investigated at the macro and micro levels. Macroscopically, it is observed that assemblies composed of angular particles exhibit higher strengths and dilations. The difference observed in bulk behavior due to particle angularity can be explained reasonably by considering particle-level mechanisms. A novel 2D image analysis technique is employed to estimate particle kinematics. Particle rotation results to be a key mechanism strongly influenced by particle shape determining the overall granular behavior. Unlike circular particles, angular ones are more resistant to rotations due to stronger interlocking and consequently exhibit higher strengths.
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Bigl, Matthew, Samuel Beal, and Charles Ramsey. Determination of residual low-order detonation particle characteristics from IMX-104 mortar rounds. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42163.

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The environmental fate and transport of energetic compounds on military training ranges are largely controlled by the particle characteristics of low-order detonations. This study demonstrated a method of command detonation, field sampling, laboratory processing, and analysis techniques for characterizing low-order detonation particles from 60 mm and 81 mm mortar rounds containing the insensitive munition formulation IMX-104. Particles deposited from three rounds of each caliber were comprehensively sampled and characterized for particle size, energetic purity, and morphology. The 60 mm rounds were command-detonated low order consistently (seven low-order detonations of seven tested rounds), with con-sumption efficiencies of 62%–80% (n = 3). The 81 mm rounds detonated low order inconsistently (three low-order detonations of ten tested rounds), possibly because the rounds were sourced from manufacturing test runs. These rounds had lower consumption efficiencies of 39%–64% (n = 3). Particle-size distributions showed significant variability between munition calibers, between rounds of the same caliber, and with distance from the detonation point. The study reviewed command-detonation configurations, particle transfer losses during sampling and particle-size analysis, and variations in the energetic purity of recovered particles. Overall, this study demonstrated the successful characterization of IMX-104 low-order detonation particles from command detonation to analysis.
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Asenath-Smith, Emily, Ross Lieblappen, Susan Taylor, Reed Winter, Terry Melendy, Robert Moser, and Robert Haehnel. Observation of crack arrest in ice by high aspect ratio particles during uniaxial compression. Engineer Research and Development Center (U.S.), February 2022. http://dx.doi.org/10.21079/11681/43145.

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In nature, ice frequently contains dissolved solutes or entrapped particles, which modify the microstructure and mechanical properties of ice. Seeking to understand the effect of particle shape and geometry on the mechanical properties of ice, we performed experiments on ice containing 15 wt% silica spheres or rods. Unique to this work was the use of 3-D microstructural imaging in a -10ºC cold room during compressive loading of the sample. The silica particles were present in the ice microstructure as randomly dispersed aggregates within grains and at grain boundaries. While cracks originated in particle-free regions in both sphere- and rod-containing samples, the propagation of cracks was quite different in each type of sample. Cracks propagated uninhibited through aggregates of spherical particles but were observed to arrest at and propagate around aggregates of rods. These results imply that spherical particles do not inhibit grain boundary sliding or increase viscous drag. On the other hand, silica rods were found to span grains, thereby pinning together the microstructure of ice during loading. These results provide insights into mechanisms that can be leveraged to strengthen ice.
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Thurston, Alison, Karen Foley, Shelby Rosten, Susan Taylor, Robert Haehnel, and Robyn Barbato. Microbial activity in dust-contaminated Antarctic snow. Engineer Research and Development Center (U.S.), September 2023. http://dx.doi.org/10.21079/11681/47681.

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During weather events, particles can accumulate on the snow near the Pegasus ice and Phoenix compacted-snow Runways at the US McMurdo Station in Antarctica. The deposited particles melt into the surface, initially forming steep-sided holes, which can widen into patches of weak and rotten snow and ice. These changes negatively impact the ice and snow runways and snow roads trafficked by vehicles. To understand the importance of microbes on this process, we examined deposited dust particles and their microbial communities in snow samples collected near the runways. Snow samples were analyzed at the Cold Regions Research and Engineering Laboratory where we performed a respiration study to measure the microbial activity during a simulated melt, isolated microorganisms, examined particle-size distribution, and performed 16S rRNA gene sequencing. We measured higher levels of carbon dioxide production from a sample containing more dust than from a sample containing less dust, a finding consistent with viable dust-associated microbial communities. Additionally, eleven microorganisms were isolated and cultured from snow samples containing dust particles. While wind patterns and satellite images suggest that the deposited particles originate from nearby Black Island, comparisons of the particle size and chemical composition were inconclusive.
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Trahan, Corey, Jing-Ru Cheng, and Amanda Hines. ERDC-PT : a multidimensional particle tracking model. Engineer Research and Development Center (U.S.), January 2023. http://dx.doi.org/10.21079/11681/48057.

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This report describes the technical engine details of the particle- and species-tracking software ERDC-PT. The development of ERDC-PT leveraged a legacy ERDC tracking model, “PT123,” developed by a civil works basic research project titled “Efficient Resolution of Complex Transport Phenomena Using Eulerian-Lagrangian Techniques” and in part by the System-Wide Water Resources Program. Given hydrodynamic velocities, ERDC-PT can track thousands of massless particles on 2D and 3D unstructured or converted structured meshes through distributed processing. At the time of this report, ERDC-PT supports triangular elements in 2D and tetrahedral elements in 3D. First-, second-, and fourth-order Runge-Kutta time integration methods are included in ERDC-PT to solve the ordinary differential equations describing the motion of particles. An element-by-element tracking algorithm is used for efficient particle tracking over the mesh. ERDC-PT tracks particles along the closed and free surface boundaries by velocity projection and stops tracking when a particle encounters the open boundary. In addition to passive particles, ERDC-PT can transport behavioral species, such as oyster larvae. This report is the first report of the series describing the technical details of the tracking engine. It details the governing equation and numerical approaching associated with ERDC-PT Version 1.0 contents.
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Taylor, S., J. Lever, K. Burgess, R. Stroud, D. Brownlee, L. Nittler, A. Bardyn, et al. Sampling interplanetary dust from Antarctic air. Engineer Research and Development Center (U.S.), February 2022. http://dx.doi.org/10.21079/11681/43345.

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We built a collector to filter interplanetary dust particles (IDPs) larger than 5 µm from the clean air at the Amundsen Scott South Pole station. Our sampling strategy used long duration, continuous dry filtering of near-surface air in place of short duration, high-speed impact collection on flags flown in the stratosphere. We filtered ~107 m³ of clean Antarctic air through 20 cm diameter, 3 µm filters coupled to a suction blower of modest power consumption (5–6 kW). Our collector ran continuously for 2 years and yielded 41 filters for analyses. Based on stratospheric concentrations, we predicted that each month’s collection would provide 300–900 IDPs for analysis. We identified 19 extraterrestrial (ET) particles on the 66 cm² of filter examined, which represented ~0.5% of the exposed filter surfaces. The 11 ET particles larger than 5 µm yield about a fifth of the expected flux based on >5 µm stratospheric ET particle flux. Of the 19 ET particles identified, four were chondritic porous IDPs, seven were FeNiS beads, two were FeNi grains, and six were chondritic material with FeNiS components. Most were <10 µm in diameter and none were cluster particles. Additionally, a carbon-rich candidate particle was found to have a small ¹⁵N isotopic enrichment, supporting an ET origin. Many other candidate grains, including chondritic glasses and C-rich particles with Mg and Si and FeS grains, require further analysis to determine if they are ET. The vast majority of exposed filter surfaces remain to be examined.
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Ham, V. Fracture of tellurium powder particles during particle size analysis. Office of Scientific and Technical Information (OSTI), June 1990. http://dx.doi.org/10.2172/6838339.

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Levchuk, Georgiy, Darby Grande, Webb Stacy, and Nathan Schurr. Cognitive Particles. Fort Belvoir, VA: Defense Technical Information Center, June 2008. http://dx.doi.org/10.21236/ada501058.

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Prescott, G. H., and B. R. Steele. Particle curtain generator for optical property measurements of solid particles. Office of Scientific and Technical Information (OSTI), January 1985. http://dx.doi.org/10.2172/6184172.

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