Page 82 - Practical Technology 2025

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Clinical Pharmacy-Pharm D Level Three 2 Semester 2024/2025 Pharmaceutical Technology (PT 607)

Lab (10): Sieving (Part 1)
Purpose
A technique used to determine the particle size distribution of a powder.
Method
This method is performed by sifting a powder sample through a stack of wire
mesh sieves where each lower sieve has a smaller aperture size than that of the
sieve above it, separating it into discrete size ranges.
A sieve shaker is used to vibrate the sieve stack for a specific period of time.
Sieves
Referred to either by their mesh size (or sieve number).
The mesh size is the number of openings per linear inch.
Approx. size range
5µm - ~3mm

Aim:

1. Determine Maximum size of aggregates.
2. Determine Nominal maximum size of aggregates

3. Determine Fineness modulus.
4. Determine Mean particle diameter.

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