Dual-sheet interferometric particle imaging for opaque particle size and 2D location measurement

2020 ◽  
Author(s):  
Zhiming Lin ◽  
Yingchun Wu ◽  
Zhu Zhuo ◽  
Xuecheng Wu
Keyword(s):  
Particle Size ◽  
Particle Imaging ◽  
Location Measurement

Real-Space Reconstructions of Non-Ideal Helical Models

1985 ◽  
Vol 43 ◽  
pp. 308-309
Author(s):  
David A. Bluemke ◽  
Bridget Carragher ◽  
Michael J. Potel
Keyword(s):  
Particle Size ◽  
Large Particle ◽  
Real Space ◽  
Two Dimensional ◽  
Large Particle Size ◽  
Variable Pitch ◽  
Negative Stain ◽  
The Fourier Transform ◽  
Particle Imaging

We have studied the effects of variable pitch, particle flattening, particle curvature, imaging noise and variable negative stain on two dimensional (2D) real-space reconstructions using electron density models of the sickle cell hemoglobin (HbS) macrofiber. The HbS macrofiber, a 500 A diameter helical particle with a pitch of about 10,000 A, is formed in vitro at pH < 7.1. The Fourier transform of the particle is extremely complex due to disorder, large particle size, and variable pitch, making the indexing required for Fourier-Bessel reconstructions very difficult. However, real-space techniques require fewer assumptions about the particle order. Preliminary particle reconstructions have led us to consider the effect of non-ideal particle imaging on the reconstruction result.

scholarly journals Stability analysis of ferrofluids

2015 ◽  
Vol 1 (1) ◽  
pp. 10-13
Author(s):  
Duda Katharina ◽  
Lüdtke-Buzug Kerstin
Keyword(s):  
Particle Size ◽  
Magnetic Particle ◽  
Imaging Technique ◽  
Medical Application ◽  
Iron Core ◽  
Shell Material ◽  
Superparamagnetic Iron Oxides ◽  
Magnetic Particle Imaging ◽  
The Stability ◽  
Particle Imaging

AbstractSuperparamagnetic iron oxides (SPIOs) are used as tracer for the new imaging technique Magnetic Particle Imaging. The stability of ferrofluids for medical application has a great importance, in addition to the particle size. The shell material, which protects the iron core prior from agglomeration and sedimentation, can be degraded by various processes. Another important aspect of stability is the constant performance of magnetisation. Therefore, the measurement of the magnetisation of the particles must be controlled in order to ensure the stability of the samples.

scholarly journals Measurement of Two Phase Flow

10.14311/716 ◽  
2005 ◽  
Vol 45 (3) ◽  
Author(s):  
J. Novotný ◽  
J. Nožička ◽  
J. Adamec ◽  
L. Nováková
Keyword(s):  
Particle Size ◽  
Spherical Particles ◽  
Experimental Setup ◽  
Wet Steam ◽  
Two Phase ◽  
Piv Method ◽  
Ccd Array ◽  
Lowered Pressure ◽  
Optical Configuration ◽  
Particle Imaging

This paper presents the results of experiments with moist wet steam. The aim of the experiment was to measure the velocity of the growth of a condensing nucleus in wet steam dependent on the velocity of condensation. For the experiments in wet steam an experimental setup was designed and constructed, which generated superheated steam at lowered pressure and a temperature of 50 °C. Low pressure and temperature of the hot vapour was chosen in order to minimize the risk of accidental disruption of the wall. The size of the condensing nucleus was measured by the method of Interferometric Particle Imaging (IPI). The IPI method is a technique for determining the particle size of transparent and spherical particles based on calculating the fringes captured on a CCD array. The number of fringes depends on the particle size and on the optical configuration. The experimental setup used is identical with the setup for measuring flow by the stereo PIV method. The only difference is the use of a special camera mount comprising a transparent mirror and enabling both cameras to be focused to one point. We present the results of the development of the growth of a condensing nucleus and histograms of the sizes of all measured particles depending on position and condensation velocity. 

Microstructural characterization of laser-melted/roller-quenched dicalcium silicate

1988 ◽  
Vol 46 ◽  
pp. 582-583
Author(s):  
C. J. Chan ◽  
K. R. Venkatachari ◽  
W. M. Kriven ◽  
J. F. Young
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Shape Change ◽  
Microstructural Characterization ◽  
Particle Size Effect ◽  
Dicalcium Silicate ◽  
Laser Melting ◽  
Uniform Size ◽  
Cell Shape Change ◽  
Wide Range

Dicalcium silicate (Ca2SiO4) is a major component of Portland cement. It has also been investigated as a potential transformation toughener alternative to zirconia. It has five polymorphs: α, α'H, α'L, β and γ. Of interest is the β-to-γ transformation on cooling at about 490°C. This transformation, accompanied by a 12% volume increase and a 4.6° unit cell shape change, is analogous to the tetragonal-to-monoclinic transformation in zirconia. Due to the processing methods used, previous studies into the particle size effect were limited by a wide range of particle size distribution. In an attempt to obtain a more uniform size, a fast quench rate involving a laser-melting/roller-quenching technique was investigated.The laser-melting/roller-quenching experiment used precompacted bars of stoichiometric γ-Ca2SiO4 powder, which were synthesized from AR grade CaCO3 and SiO2xH2O. The raw materials were mixed by conventional ceramic processing techniques, and sintered at 1450°C. The dusted γ-Ca2SiO4 powder was uniaxially pressed into 0.4 cm x 0.4 cm x 4 cm bars under 34 MPa and cold isostatically pressed under 172 MPa. The γ-Ca2SiO4 bars were melted by a 10 KW-CO2 laser.

Analytical Electron Microscopy study of two vehicle-aged automotive exhaust catalysts having dissimilar activities

1989 ◽  
Vol 47 ◽  
pp. 272-273
Author(s):  
Sooho Kim ◽  
M. J. D’Aniello
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Noble Metal ◽  
Catalyst Deactivation ◽  
Analytical Electron Microscopy ◽  
Microscopy Study ◽  
Metal Particles ◽  
Automotive Exhaust ◽  
Exhaust Catalysts ◽  
Analytical Electron

Automotive catalysts generally lose-agtivity during vehicle operation due to several well-known deactivation mechanisms. To gain a more fundamental understanding of catalyst deactivation, the microscopic details of fresh and vehicle-aged commercial pelleted automotive exhaust catalysts containing Pt, Pd and Rh were studied by employing Analytical Electron Microscopy (AEM). Two different vehicle-aged samples containing similar poison levels but having different catalytic activities (denoted better and poorer) were selected for this study.The general microstructure of the supports and the noble metal particles of the two catalysts looks similar; the noble metal particles were generally found to be spherical and often faceted. However, the average noble metal particle size on the poorer catalyst (21 nm) was larger than that on the better catalyst (16 nm). These sizes represent a significant increase over that found on the fresh catalyst (8 nm). The activity of these catalysts decreases as the observed particle size increases.

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