An air monitoring network using continuous particle size distribution monitors: Connecting pollutant properties to visibility via Mie scattering calculations

Polydisperse suspensions with particles of a finite number N of size classes have been widely studied in laboratory experiments. However, in most real-world applications the particle sizes are distributed continuously. In this paper, a well-studied one-dimensional kinematic model for batch sedimentation of polydisperse suspensions of small equal-density spheres is extended to suspensions with a continuous particle size distribution. For this purpose, the phase density function Φ = Φ(t, x, ξ), where ξ ∈ [0, 1] is the normalized squared size of the particles, is introduced, whose integral with respect to ξ on an interval [ξ1, ξ2] is equivalent to the volume fraction at (t, x) occupied by particles of that size range. Combining the Masliyah–Lockett–Bassoon (MLB) model for the solid-fluid relative velocity for each solids species with the concept of phase density function yields a scalar, first-order equation for Φ, namely the equation of the generalized kinetic theory. Three numerical schemes for the solution of this equation are introduced, and a numerical example and an L1 error study show that one of these schemes introduces less numerical diffusion and less spurious oscillations near discontinuities than the others. Several numerical examples illustrate the simulated behavior of this kind of suspensions. Numerical results also illustrate the solution of an eigenvalue problem associated with the equation of the generalized kinetic theory.

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Online Continuous Particle Size Distribution Analysis for Grinding Process in a Jet Mill

Journal of the Society of Powder Technology Japan ◽

10.4164/sptj.54.483 ◽

2017 ◽

Vol 54 (7) ◽

pp. 483-486

Author(s):

Fumiaki Sato ◽

Hideyuki Ikeda ◽

Michio Osumi ◽

Yasuyuki Fujita ◽

Isamu Minami ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Grinding Process ◽

Distribution Analysis ◽

Continuous Particle

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Influence of Cement Particle Size Distribution on Strength of Hardened Cement Paste

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.477.118 ◽

2011 ◽

Vol 477 ◽

pp. 118-124

Author(s):

Bao Lin Zhu ◽

Xin Huang ◽

Ye Guo

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Cement Paste ◽

Solid Phase ◽

Hardened Cement ◽

Cement Particle ◽

Hardened Cement Paste ◽

Effect Of Particle Size ◽

Continuous Particle

On the basis of the principle for the highest filling degree of cement hydrates, it is synthetically considered that a matching connection between hydration of cement, volume increment of solid phase and packing density of cement paste, a calculation method for a connection between cement continuous particle size distribution and strength of hardened cement paste is developed and tested by experiment. Based on above-mentioned analysis, a tentative research on the effect of particle size distribution of cement on strength is carried out.

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Prediction of Aerosol Particle Size Distribution Based on Neural Network

Advances in Meteorology ◽

10.1155/2020/5074192 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Yali Ren ◽

Jiandong Mao ◽

Hu Zhao ◽

Chunyan Zhou ◽

Xin Gong ◽

...

Keyword(s):

Neural Network ◽

Integral Equation ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Bp Neural Network ◽

Scattering Theory ◽

Mie Scattering ◽

Aerosol Particle Size ◽

Mie Scattering Theory

Aerosol plays a very important role in affecting the earth-atmosphere radiation budget, and particle size distribution is an important aerosol property parameter. Therefore, it is necessary to determine the particle size distribution. However, the particle size distribution determined by the particle extinction efficiency factor according to the Mie scattering theory is an ill-conditioned integral equation, namely, the Fredholm integral equation of the first kind, which is very difficult to solve. To avoid solving such an integral equation, the BP neural network prediction model was established. In the model, the aerosol optical depth obtained by sun photometer CE-318 and kernel functions obtained by Mie scattering theory were used as the inputs of the neural network, particle size distributions collected by the aerodynamic particle sizer APS 3321 were used as the output, and the Levenberg–Marquardt algorithm with the fastest descending speed was adopted to train the model. For verifying the feasibility of the prediction model, some experiments were carried out. The results show that BP neural network has a better prediction effect than that of the RBF neural network and is an effective method to obtain the aerosol particle size distribution of the whole atmosphere column using the data of CE-318 and APS 3321.

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Particle Packing Application for Improvement in the Properties of Compressed Stabilized Earth Blocks with Reduced Clay and Silt

Engineering, Technology & Applied Science Research ◽

10.48084/etasr.3002 ◽

2019 ◽

Vol 9 (4) ◽

pp. 4538-4542

Author(s):

S. N. Malkanthi ◽

A. A. D. A. J. Perera

Keyword(s):

Particle Size ◽

Compressive Strength ◽

Particle Size Distribution ◽

Size Distribution ◽

Particle Packing ◽

Correct Selection ◽

Soil Mixture ◽

Silt Content ◽

Earth Blocks ◽

Continuous Particle

Soil as a building material has been used in different forms such as mud, adobe, rammed earth and bricks. The present study focuses on producing Compressed Stabilized Earth Blocks (CSEBs) giving attention to the particle size distribution in the soil mixture. The literature established that compressive strength significantly depends on clay and silt content and 25% of clay and silt produce optimum results while no attention has been given to the amount of other, larger particles. Soil grading refers to the combination of different-size particles in a soil mixture. The correct selection of sizes in the correct proportion may cause improvements in CSEB properties. This paper explains the application of particle packing technology for the improvement of CSEB properties. The theoretical concepts provide a continuous particle size distribution, and the soil used for the experiments also has a continuous particle size distribution. The soil used in the experiments was subjected to washing to reduce the clay and silt content. Separated clay and silt and large particles of different sizes were added to the mixture to match particle size distribution to the optimization curves as explained in particle packing theories. The experimental results show that the CSEB properties can be significantly improved by modifying particle size distribution to fit the suggested optimization curves. According to the results, the compressive strength improved by more than 50% with different amounts of cement stabilization. Significant improvements in the dry densities and water absorption ratios of blocks were observed with this particle size modification.

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Influence of Cement Particle Size Distribution on Strength of Cement Paste

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.1007 ◽

2011 ◽

Vol 194-196 ◽

pp. 1007-1011

Author(s):

Bao Lin Zhu ◽

Xin Huang ◽

Ye Guo

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Cement Paste ◽

Solid Phase ◽

Cement Particle ◽

Filling Degree ◽

Volume Increment ◽

Effect Of Particle Size ◽

Continuous Particle

On the basis of the principle for the highest filling degree of cement hydrates, it is synthetically considered that a matching connection between hydration of cement, volume increment of solid phase and packing density of cement paste, a calculation method for a connection between cement continuous particle size distribution and strength of cement paste is developed and tested by experiment. Based on above-mentioned analysis, a tentative research on the effect of particle size distribution of cement on strength is carried out.

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