Stress-controlled applications

Evageliou, V, Alevisopolous, S., and Kasapis, S. 1997. Application of stress-controlled analysis to the development of low-fat spreads, y. Texture Stud. 28 319-335. 

Controlled application of different kinds of stress, in particular, thermal, mechanical, and (bio)chemical impacts, supplies information about the response capabilities of solvent/polysaccharide systems and provides data on phase transitions, disintegration or reorganization phenomena, gel qualities, and degree of resistance or stability. But even there, any of the obtained characteristics may occur as distributions, illustrating that heterogeneity is a generic quality of polysaccharides. 

Low stress decreases the attentiveness because uninteresting and little exacting tasks cause a decrease of attention. Low stress is applicable, for example, to routine control walks. 

We have stressed the application of this new method to the geosciences however, it is also suggested for use in medicine, food control and nutrition. Whereas in the n-alkanes the deviation from normal was very small, in branched and alicyclic biomarkers the diversity is from ca — 21%o to — 73.4%o ( C). Because of the low concentration of the... 

Loading can be either load (or stress) controlled, displacement (or strain) controlled, or something in between. Examples include aerodynamic loads on an aircraft (see Aerospace applications), which tend to be load controlled, and the displacement of a sealant between relatively stiff adherends, which is displacement controlled. Because average adhesive strain, in its simplest form, is defined as displacement divided by bond thickness, strains and resulting stresses are higher in thin bondlines subjected to displacement-controlled loading scenarios. Joints loaded in such a manner often perform better with thicker bondlines. Displacement-controlled situations include thermal expansion/shrinkage of adherends, mismatched adherend expansion, and attachments bonded to pressure vessels or other adherends that are stressed. 

Since most DMA experiments are run at very low strains ( 0.5% maximum) to stay well within a polymer s linear region, it has been reported that both the analyzers give the same results. However, when one gets to the nonlinear region, the difference becomes significant, as stress and strain are no longer linearly related. Stress control can be said to duplicate real-life conditions more accurately since most applications of polymers involve resisting a load. 

The Institute has many-year experience of investigations and developments in the field of NDT. These are, mainly, developments which allowed creation of a series of eddy current flaw detectors for various applications. The Institute has traditionally studied the physico-mechanical properties of materials, their stressed-strained state, fracture mechanics and developed on this basis the procedures and instruments which measure the properties and predict the behaviour of materials. Quite important are also developments of technologies and equipment for control of thickness and adhesion of thin protective coatings on various bases, corrosion control of underground pipelines by indirect method, acoustic emission control of hydrogen and corrosion cracking in structural materials, etc. 

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