Search

In order to confirm reliable particle size measurement technique and to prepare standard reference particles for calibrating particle size measurement devices, uncertainty region of count and mass based size distribution have been theoretically examined. The uncertainty region of count base cumulative size distribution is smaller than that of the mass base cumulative distribution. The uncertainty region of count base cumulative size distribution is nearly constant over wide range of particle diameter and the region is nearly constant for sample size greater than about 20,000. On the other hand, the uncertainty region of mass base cumulative distribution increases with the increase of particle diameter. The reliability of theoretical uncertainty region is confirmed by the experimental data of particle size measurement. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simulation was carried out for a picket fence distribution composed of two kinds of nearly mono-disperse particles. [•] The uncertainty region increases around the intermediate particle diameter regions. [•] The uncertainty regions of vertical and horizontal directions were calculated. [•] The uncertainty region decreases with the increase of sample size. [•] Necessary sample size to obtain reliable size distribution was determined. [Copyright &y& Elsevier]

Abstract: In order to confirm the reliability of particle size measurement technique and to prepare standard reference particles for calibrating particle size measurement devices, experimental and theoretical studies have been conducted about the uncertainty region of particle size measurement for the general particle size distribution. A new theoretical equation to calculate fundamental uncertainty region in the case that the maximum and minimum particle sizes are known, is derived based on Tschebyscheff theory. The uncertainty regions calculated based on the proposed method are applied to poly-disperse particles and a picket-fence distribution composed of two kinds of nearly mono-disperse particles. For the poly-disperse particles, the uncertainty region increases with the increase in particle diameter. For the picket-fence distribution composed of two kinds of nearly mono-disperse particles, the uncertainty region increases around the intermediate particle diameters between the two kinds of particles. Numerical simulation of uncertainty region for the picket-fence distribution has also been carried out. The uncertainty region decreases with the increase in sample size or the decrease in geometric standard deviation. [Copyright &y& Elsevier]

Abstract: In order to confirm the reliability of particle size measurement technique and to prepare standard reference particles for calibrating particle size measurement devices, experimental and theoretical studies have been conducted through particle size measurement of silica particles having a size range of 0.1–1μm. A new theoretical equation to calculate fundamental uncertainty region in the case that the maximum and/or the minimum particle size is known, is derived based on a log-normal distribution truncated by the maximum and/or the minimum. Fundamental uncertainty regions calculated based on these truncated size distributions are compared with that calculated based on the perfect log-normal distribution. The relationship between the parameter u to determine the reliability of size distribution and the truncate-parameter g is obtained to get 95% reliability of the measurement. Value of the parameter u is fairly reduced as the truncate-parameter g becomes smaller. Numerical simulation of uncertainty region agreed with the results calculated by the new theoretical equation. Calculations on the silica particles having a size range of 0.1–1μm have been conducted showing that the uncertainty region based on the known maximum size is slightly smaller compared to that given in the previous paper. [Copyright &y& Elsevier]

Abstract: In order to confirm reliable particle size measurement technique and to prepare standard reference particles for calibrating particle size measurement devices, experimental and theoretical studies have been conducted about particle size measurement of 0.1–1μm silica particles. The microscopic method with sample size greater than 90,000 particles was conducted for the size measurement. Theoretical equation of uncertainty region over all particle diameter range is newly proposed and compared with computer simulation. Previous paper [H. Masuda, K. Iinoya, Theoretical study of the scatter of experimental data due to particle size distribution, J. Chem. Eng. 4(1) (1971) 60–67] reported the uncertainty region only for mass median diameter, but this paper presents the uncertainty region for all particle size range. The uncertainty region increases with the increase in particle diameter and also increases as the sample size decreases. Theoretical uncertainty region agreed with the results of computer simulation. [Copyright &y& Elsevier]

In order to prepare standard reference particles, experimental and theoretical studies have been conducted on particle size measurement of two kinds of spherical glass beads. The sheath flow-type electrical sensing zone method and the revised sedimentation balance method were used for the measurement. The data were compared with those obtained by the microscopic method with a sample size greater than 10 000. The particle size distributions obtained by use of the sheath flow-type electrical sensing zone method and microscopic method are nearly equal for the two kinds of glass beads. However, deviations of less than 5% were observed between the improved sedimentation balance and microscopic methods. The experimental data of the microscopic method are within the 95% reliability region of the sheath flow-type electrical sensing zone method. [ABSTRACT FROM AUTHOR]