Particle & Particle Systems Characterization

Cover image for Particle & Particle Systems Characterization

September, 2007

Volume 24, Issue 3

Pages 155–245

  1. Contents

    1. Top of page
    2. Contents
    3. Research Articles
    4. Calendar
    5. Instructions for Authors
  2. Research Articles

    1. Top of page
    2. Contents
    3. Research Articles
    4. Calendar
    5. Instructions for Authors
    1. Resolving Concentrated Particle Size Mixtures Using Dynamic Light Scattering (pages 159–162)

      Michael Kaszuba, Malcolm T. Connah, Fraser K. McNeil-Watson and Ulf Nobbmann

      Version of Record online: 21 JUN 2007 | DOI: 10.1002/ppsc.200601035

      Conventional dynamic light scattering measurements are limited to low concentrations due to the onset of multiple scattering. A device using non-invasive backscatter optics is tested measuring a series of latex mixtures at volume concentrations up to 1 %. It is shown that the device accurately determines particle size and has a very good resolution of different size populations.

    2. Particle Systems Characterization Using a Flat Cell Static Light Scattering Apparatus (pages 163–172)

      Guillermo E. Eliçabe, Walter F. Schroeder, Gloria L. Frontini and Valeria Pettarin

      Version of Record online: 11 JUL 2007 | DOI: 10.1002/ppsc.200600995

      In this work a light scattering apparatus for the study of a polymerization induced phase separation is presented. A Fraunhofer configuration is used consisting of a linear array of photodiodes to detect the light scattered by thin samples illuminated by a He-Ne laser. The ability of the setup is quantitatively analyzed using microspherical polystyrene standards. The system was then successfully applied to the evolving particle system and the results agree well with previous knowledge of the system.

    3. Improving the Robustness of Particle Size Analysis by Multivariate Statistical Process Control (pages 173–183)

      Marko Mattila, Kari Saloheimo and Kari Koskinen

      Version of Record online: 11 JUL 2007 | DOI: 10.1002/ppsc.200701094

      The robustness of online particle size analysis in wet processes is improved by applying data based modeling methods. It is shown that the proposed method works with two very different slurry types at two mineral processing plants. The main advantage of the adapted approach is that there are no adjustable parameters that have to be set by the user.

    4. Advanced Geometrical Modeling of Focused Beam Reflectance Measurements (FBRM) (pages 184–192)

      Norbert Kail, Heiko Briesen and Wolfgang Marquardt

      Version of Record online: 19 JUL 2007 | DOI: 10.1002/ppsc.200601036

      FBRM has been established as versatile particle characterization technique. This paper addresses several assumptions usually made in order to convert measured chord length distributions to particle size distributions. It is shown that these assumptions often do not hold even for rather ideal cases and two more refined modeling approaches are proposed and verified.

    5. Impact Fragmentation of Metal Nanoparticle Agglomerates (pages 193–200)

      Martin Seipenbusch, Petya Toneva, Wolfgang Peukert and Alfred P. Weber

      Version of Record online: 11 JUL 2007 | DOI: 10.1002/ppsc.200601089

      Fragmentation of gas-borne nanoscaled aggregates is studied in this paper interpreted in terms of interparticle forces. It is shown that van der Waals forces are dominant for Pt and Ag but much stronger forces are active in case of Ni particles which can be attributed to magnetic dipole moments. The method promises to be very valuable in studying bond strength and cohesiveness of industrial nanoparticle powders.

    6. Measurement of Slug Length and Slug Velocity in Pneumatic Conveying Using Capacitive Sensing (pages 201–209)

      Anton Fuchs and Hubert Zangl

      Version of Record online: 11 JUL 2007 | DOI: 10.1002/ppsc.200600998

      This paper describes a newly designed capacitive sensor to determine the slug length and the slug velocity in pneumatic dense phase conveying. The novel evaluation algorithm is shown to enable a robust operation and to feature sub-sample resolution for the flow parameters obtained. A number of experiments are conducted demonstrating the applicability of the set-up in pneumatic dense phase conveying.

    7. Gas-Solid Flow in a Two-Dimensional Cross-Flow Moving Granular Filter Bed with a Symmetric Boundary (pages 210–222)

      Chuen-Shii Chou, Ang-Fen Lee and Chun-Hung Yeh

      Version of Record online: 21 JUN 2007 | DOI: 10.1002/ppsc.200500968

      This study investigates how the inlet gas velocity and the louver angle affect the granular flow in moving granular filter beds. Simulations were performed using a discrete element method (DEM) coupled with the flow field simulation. In addition, experiments show reasonable agreement.

    8. Fractal Aspects of Powder Flow and Densification (pages 223–228)

      Albert Mihranyan and Maria Strømme

      Version of Record online: 11 JUL 2007 | DOI: 10.1002/ppsc.200601085

      Powder flowability is strongly affected by surface structure. In this work, a relationship is presented between the reactive fractal dimension and the density of a powder bed during densification. The new concept is tested for a model system of microcrystalline cellulose particles and it is suggested that this concept can be used for describing powder flow behavior and the sensitivity of powder flowability to particle size.

    9. Effect of Grinding Media Shapes on Breakage Parameters (pages 229–235)

      Halil Ipek

      Version of Record online: 11 JUL 2007 | DOI: 10.1002/ppsc.200601095

      In the present study, the effect of grinding media shape on breakage parameters is studied. It is demonstrated that the grinding of quartz obeys first-order breakage kinetics in all cases but that higher breakage rates were obtained with cylpebs than with balls. Furthermore, the primary breakage distribution function is independent of the grinding media shape.

    10. Dry Grinding of Mefenamic Acid Particles for Enhancement of its Water Dissolution Rate (pages 236–241)

      Tomohiro Iwasaki, Maiko Takahara, Ryoichi Sonoda and Satoru Watano

      Version of Record online: 21 JUN 2007 | DOI: 10.1002/ppsc.200601091

      This paper studies the physico-chemical changes of mefenamic acid upon dry grinding. These changes are studied by specific surface area, X-ray diffraction, differential scanning calorimetry and infrared spectroscopy, as well as the resulting dissolution rates that the amorphization. It is shown that amorphization level increases with progressing grinding leading to an improved dissolution rate even after attaining the grinding limit.

  3. Calendar

    1. Top of page
    2. Contents
    3. Research Articles
    4. Calendar
    5. Instructions for Authors
  4. Instructions for Authors

    1. Top of page
    2. Contents
    3. Research Articles
    4. Calendar
    5. Instructions for Authors