Changes in pH induced by temperature

The reaction is reversible on cooling after heating to moderate temperatures but becomes only partially reversible following more severe heating. The shifts in calcium phosphate equilibrium and pH increase when milk is concentrated. 

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The strength of wood can be altered by environmental agents. The changes in pH, moisture, and temperature the influence of decay, fire, and UV radiation and the adsorption of chemicals from the environment can have a significant effect on strength properties. Environmentally induced changes must be considered in any discussion on the strength of treated or untreated wood. 

Some chemical substances have been used in the past as switches to control ion transport. Several new molecular sensory devices, which are responsive crown ethers used for the dynamic control of cation and anion binding induced by changes in pH, redox potential, temperature, light, and magnetic and electrical field, have been developed. These new ligands possess chromophores or fluorophores linked to the macrocycle, and display drastic variations in their photochemical and/or luminescent properties upon cation complexation. 

That which we call a rose, by any other name would smell as sweet. The essence of the denatured state, in contrast, is rather more elusive. The difficulty stems, at least in part, from the wide variety of methods of inducing a protein to unfold. Some proteins appear to be natively unfolded that is, they remain unfolded in the cell under conditions in which they retain their biological activity (Plaxco and Gross, 1997 Wright and Dyson 1999 Dunker, 2002). Other proteins unfold only under the influence of changes in pH, high or low temperatures, or... 

Emulsilication through phase inversion is based on a change in the surfactant spontaneous curvature induced by temperature. This concept can be generalized considering any parameter influencing the spontaneous curvature of a surfactant, for example, salinity, pH, presence of a cosurfactant, and nature of the oil. The concept of inversion has often been reported in the literature by means of a formulation-composition map. In the following, we shall sum up this empirical approach which can be useful for formulators. 

The introduction in the early 1980s of the concept of in situ gel systems demonstrated that a considerable prolongation in duration of action could be obtained. In situ gelling systems have unique properties, which can make a liquid change phase to a gel or sohd phase in the culde-sac upon its instillation into the eye. Three methods have been employed to induce phase transition on the eye surface change in pH and temperature as well as activation by ions. 

Petrovic AG, Polavarapu PL (2005) Structural transitions in polyriboadenylic acid induced by the changes in pH and temperature vibrational circular dichroism study in solution and film states. J Phys Chem B 109 23698-23705... 

An elastic network can be formed both in bulk, induced by a heating cycle causing denaturation of the protein, and at an interface, induced by adsorption, which likely caused changes in the conformation. The network formed at the air-protein solution interface can be considered as a kind of two dimensional gel. At low pH, a gel is more readily formed in bulk (lower heating temperature required)30,31 as well as at the air-protein solution surface. Likely, both phenomena are related to a lower stability of the molecule against conformational changes caused by external factors. 

Gel-liquid crystalline transitions can also be induced isothermally by changes in pH, Ca and ionic strength [109=111] in negatively charged phospholipids. Especially the effect of Ca " can be dramatic. Ca " can increase the transition temperature of phosphatidylglycerol and phosphatidylserine by more than 50 °C, thereby forming a so-called cylindrical [110] or cochleated structure [112], Recently it has... 

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