Associated with Weight Change

Isobaric Weight-change Determination. A technique of obtaining a record of the equilibrium weight of a substance as a function of temperature (71 at a constant partial pressure of the volatile product or products. 

The record is the isobaric weight-change curve it is normal to plot weight on the ordinate with weight decreasing downward, and T on the abscissa increasing from left to right. 

Thermogravimetry (TG). A technique whereby the weight of a substance, in an environment heated or cooled at a controlled rate, is recorded as a function of time or temperature. 

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DSC, DTA, TMA, and TBA analyses are all interrelated, all signaling changes in thermal behavior as a function of heating rate or time. TGA is related to the other analyses in the assignment of phase changes associated with weight changes. 

Williams et al. (37) found that the decrease in body weight due to exercise was associated with an Increase in plasma HDL cholesterol concentration in middle-aged men. They suggested that processes associated with weight change may produce many, but not all, of the changes in HDL cholesterol that had been previously associated with exercise. 

Calsequestrin is a calcium-storage protein found in the sacroplasmic reticulum, which binds about 50 calcium ions per monomer (molecular weight 40 000) with binding constants in the range 103-105 dm3 mol. Release and uptake of Ca2+ during muscle contradion and relaxation involve this store. Calsequestrin from rabbit skeletal muscle has a random coil conformation in the absence of calcium. Binding of Ca2+ is associated with a change to a more compact structure.267... 

In other studies with rats, intermediate and chronic oral exposure to barium chloride and barium acetate in drinking water have not been associated with any changes in heart weight or with any gross or microscopic lesions of the heart (Schroeder and Mitchener 1975a Tardiff et al. 1980). 

These reactions would be expected to cause a permanent volume expansion inasmuch as nephelite has a lower true specific gravity than the weighted mixture of the original corundum, silica, and mullite. The bulk volume increase of about 14% was associated with the change in mineralogy. This fact, coupled with the increase in thermal expansion of the outer layer, which contained alkalies, results in slabbing or shelling of the surface. 

The losses of weight have been associated with valence changes of the molybdenum with time as shown in Fig. 4. As can be seen, it would take extremely long times to reduce the molybdena to M0O2. 

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