Particle & Particle Systems Characterization

Cover image for Particle & Particle Systems Characterization

June, 2005

Volume 22, Issue 1

Pages 1–73

    1. Shape and Size Determination by Laser Diffraction: Average Aspect Ratio and Size Distributions by Volume; Feasibility of Data Analysis by Neural Networks (pages 5–13)

      Luc Deriemaeker and Robert Finsy

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400960

      A new strategy for the recovery of the average shape factor and the volume weighted size distribution from laser diffraction data using neural networks is presented. The method yields reliable estimates for both, the shape factor and the volume weighted size distribution.

    2. Transmission Fluctuation Spectrometry in Concentrated Suspensions. Part Three: Measurements (pages 14–23)

      Jianqi Shen and Ulrich Riebel

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400887

      Transmission fluctuation spectrometry (TFS) has proved to be a valuable tool for particle size analysis in flowing particle suspensions. Following theoretical considerations in the previous parts of this publication series an experimental study in concentrated suspensions is presented here. By introducing an empirical correction in the inversion algorithm, it is possible to obtain the particle size distribution and particle concentration over broad ranges of particle sizes and concentrations.

    3. Transmission Fluctuation Spectrometry with Spatial Correlation (pages 24–37)

      Jianqi Shen, Ulrich Riebel and Xiaoai Guo

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400896

      This paper presents a new way to realize transmission fluctuation spectrometry (TFS) by using two narrow parallel beams. While changing the beam separation, the transmission fluctuations of these two beams are recorded. Analytical expressions for the signal to be expected from monolayers as well as three-dimensional suspensions are derived. The applicability of this new set-up to estimate particle size distributions and concentrations is discussed in detail.

    4. Expansions in Free Space of Arbitrary Quantum Wavepackets, Quantum Laser Beams, and Gaussian Quantum (On-axis and Off-axis) Laser Beams in Terms of Free Spherical Waves (pages 38–44)

      Gérard Gouesbet

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400959

      This paper investigates the scattering of quantum wave packets, quantum laser beams and quantum Gaussian laser beams by homogeneous spheres. In order to establish an electromagnetic quantum generalized Lorenz-Mie theory the description of the incident quantum state is performed by using spherical partial waves.

    5. Numerical Calculation of London-van der Waals Adhesion Force Distributions for Different Superquadric Shaped Particles (pages 45–51)

      Jost-Peter Sonnenberg and Eberhard Schmidt

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400904

      This paper uses a numerical algorithm to predict adhesion force distributions of different kinds of superquadric shaped particles. Furthermore the adhesion force distributions of corresponding 2D-projections are calculated and compared. Using a correlation of both distributions promises to reduce the computational time and effort for bigger particles and particle collectives.

    6. The Wall Stresses and Insert Load in a Two-Dimensional Flat-bottomed Bin with an Equilateral Triangle Insert (pages 52–62)

      Chuen-Shii Chou and Chun-Yuan Tseng

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400958

      Powder flow in a 2D flat-bottomed bin with a triangle insert is tested experimentally. The wall stresses and the insert load are investigated and compared to theoretical predictions. It is shown how the insert acts to disrupt the contact network above. This may help to improve understanding of pulsation phenomena.

    7. Statistical Analysis of Pellet Size Variation in Commercial Catalysts (pages 63–68)

      Dongfang Wu, Jiancheng Zhou and Yongdan Li

      Version of Record online: 2 JUN 2005 | DOI: 10.1002/ppsc.200400907

      Different statistical test methods are compared to fit measured diameter and length distributions of spherical pellets and cylindrical tablets, respectively. It is shown, how the most appropriate type of distribution can be chosen. Furthermore, the shape of the distributions is explained by the respective production method.