what is aquaculture????
Answers
Aquaculture is the controlled process of cultivating aquatic organisms, especially for human consumption. It’s a similar concept to agriculture, but with fish instead of plants or livestock. Aquaculture is also referred to as fish farming. The seafood that you find at your local grocery store is likely labeled as farmed fish. Aquaculture can happen all over the world, and it does: in coastal ocean waters, freshwater ponds and rivers, and even on land in tanks.
Water absorption test on bricks are conducted to determine durability property of bricks such as degree of burning, quality and behavior of bricks in weathering.
A brick with water absorption of less than 7% provides better resistance to damage by freezing. The degree of compactness of bricks can be obtained by water absorption test, as water is absorbed by pores in bricks.
The water absorption by bricks increase with increase in pores. So, the bricks, which have water absorption less than 3 percent can be called as vitrified.
This test�provides� the percentage of water absorption of bricks and procedure of the same is discussed below.
�Apparatus
A sensitive balance capable of weighing within 0.1% of the mass of the specimen and ventilated oven
Specimen
Three numbers of whole bricks from samples collected for testing should be taken.
Procedure of Water Absorption Test
Dry the specimen in a ventilated oven at a temperature of 105 �C to 115�C till it attains substantially constant mass.
Cool the specimen to room temperature and obtain its weight (M1) specimen too warm to touch shall not be used for this purpose.
Immerse completely dried specimen in clean water at a temperature of 27+2�C for 24 hours.
Remove the specimen and wipe out any traces of water with damp cloth and weigh the specimen after it has been removed from water (M2).
Calculation of Water Absorption of Bricks
Water absorption, % by mass, after 24 hours immersion in cold water in given by the formula,
w = \frac{m2 - m1}{m1}w=
m1
m2−m1
The average of result shall be reported.
Result
Water absorption of the given bricks = ………….%
Water Absorption Values for Bricks
When tested as above, the average water absorption shall not be more than 20% by weight up to class 12.5 and 15% by weight for higher class.