Permanent 2-17 structure

At temperatures in the range of 850 to 950 °F (454—510 °C), permanent structural changes, such as spheroidization, take place in the boiler steel. In this process, the pearlite phase component disappears as the laminar cementite gradually changes into spherical grains. 

Malformations—Permanent structural changes that may adversely affect survival, development, or function. 

Type 2 gels are essentially infinite molecular weight molecules Their three-dimensional macroscopic networks comprise structural components that are covalently linked through multifunctional units. This is a very broad class that includes linear polymers that have been chemically or radiochemically cross-linked into a permanent structure as well as networks that have been built up by the step or chain polymerization of difunctional and multifunctional monomers. 

Since cations are adsorbed electrostatically not only due to the permanent structural charge, a0, (caused by isomorphic substitution) but also due to the proton charge, oh, (the charge established because of binding or dissociating protons -see Chapter 3.2) the ion exchange capacity is pH-dependent (it increases with pH). Furthermore, the experimentally determined capacity may include inner-spherically bound cations. 

Foliage and flowers While trees and shrubs form the permanent structure of most garden plantings, herbaceous plants bring a wealth of seasonal variety. 

Process of progressive, localized, permanent, structural change occurring in a material subjected to fluctuating external stimuli. 

---