The weak acid cation-exchange resins are not styrenics. They are acrylic or methacrylic esters or nitriles copolymerized with DVB and then hydrolyzed to give the free carboxylic acids. The weal acid group is effective as a base adsorbed for strongly basic materials.

Structural analyses include the set of physical laws and mathematics required to study and predict the behavior of structures. The subjects of structural analysis are engineering artifacts whose integrity is judged largely based upon their ability to withstand loads. It includes buildings, bridges, aircraft, and ships. Structural analysis incorporates the fields of mechanics and dynamics.

Structural angles have L-shaped sections. Both legs of an angle have the same thickness. These angles are identified by the letter L, followed by the dimensions of the legs and its thickness. These angles are used singly or in pairs as tension or compression members in trusses and brackets. These angles are used in a wide range of applications including manufacturing construction of low-rise buildings, agricultural machinery and barge-building.