Page 83 - Practical Technology 2025

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

Advantages Disadvantages
1. Easy to perform 1. Known problems of reproducibility
2. Wide size range 2. Wear/damage in use or cleaning
3. Inexpensive 3. Irregular/agglomerated particles
4. Rod-like particles : overestimate of
under-size
5. Labour
6. Intensive

a. Maximum Size of Aggregate:
The smallest size of sieve through which the entire amount of aggregate can

pass.

Example:

Take 400g sample of 20 mm aggregate. This 20 mm aggregate can easily pass
through the sieve of 25 mm, 30 mm, 40 mm, 50 mm. because the size of 20
mm is lesser than above sieves.

In this scenario, the smallest size of sieve through which 20 mm aggregate can
pass is 25 mm.
Therefore, the maximum size of aggregate is 25 mm.
Determine Maximum size of aggregates in the following particles:

Med point of size Frequency
range (n)

3.7 0
3.2 0
2.7 17
2.2 54
1.7 22

1.2 10
0.7 2
The Maximum size of aggregates is (3.2)

b. Nominal Maximum Size of Aggregate:

The smallest size of sieve through which the entire amount of aggregate can pass.
But it may retain 10% of total weight of aggregate.

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