Deformation structure

Jonasson, I.R. Goodfellow, W.D. 1986. Sedimentary and diagenetic textures, and deformation structures within sulfide zone of Howards Pass (XY) Zn-Pb deposit, Yukon and Northwest Territories. In Mineral Deposits of Northern Cordillera, Special Volume 37, Canadian Institute of Mining and Metallurgy, 51-70. 

One of plausible candidates for the entropy source is a dynamic structural disorder in the HS phase, which should be settled down in the LS phase. The crystallographic data for [Mn(taa)] [11] provide a clue, i.e., the presence of C3 axis in the HS molecule. An Mn(III) ion in the 5E state is a well-known Jahn-Teller ion [19]. Since the C3 site-symmetry cannot lift the orbital degeneracy of the 5E term (Fig. 1(b)), it is likely that the Mn ion is subjected to the E e Jahn-Teller effect, which gives rise to three energetically equivalent deformation structures. The apparent C3 symmetry should be observed in a time-averaged structure over three deformed structures. 

In uniformly strained materials, deformation structures can be readily observed using transmission electron microscopy. However, it is much more difficult to prepare a similar sample where the deformation is more localized, as is the case of nanoindentation. Recently this situation has been revolutionized by the development of focused ion beam techniques for semiconductor processing, so that it is possible to select the region to be thinned to within 100 nm (Overwijk et al., 1993 Saka, 1998). 

Fig. (a) Representation of the aromatic ring (b) deformed structure resulting from fixed bonds. 

To understand the capability of this technique to produce deformed structures, it is useful to compare the strain induced by ECAE with equivalent strains produced during conventional metal-forming processes. A reduction in area during an ideal extrusion, Re, produces a strain 8re that is equal to the ratio of the areas, Aq/Aj. Table 7.5 compares the strain for N ECAE passes with the equivalent reduction in area needed to produce the same strain in an ideal extrusion. After eight... 

Did you know that if you extracted all the DNA from your cells and put them end to end, they would stretch to the sun and back 600 times This is because we have approximately 10 trillion cells in our body and each cell contains thousands of DNA molecules. These cell molecules are under constant chemical and environmental attack and so there is a similar number of repair events to restore these structures. There are approximately 1020 harmful attacks on the cells of our bodies each day from chemicals, oxidizing free radicals, uv light, cigarette smoke, etc. Unless repair is done quickly, these cells can form deformed structures and cause many molecular-based diseases, including cancers. This is why a constant supply of food in a balanced diet is essential for healthy living. Snack food and slimming diets sometimes lack essential proteins and minerals. 

Geometry of cyclopropene and its deliberately deformed structure, s-characters (in %) of hybrid orbitals and Lowdin 7r-bond orders. 

Figure 19.14 TEM images of the deformation structure in sPS, rubber modified with 15% Kraton and 20% S//BA particles produced in microsuspension (a) injection moulded sample (b) annealed sample...

Figure 19.15 TEM images of the deformation structure in sPS modified with S//BA core-shell (35 %) after deformation at 110 °C (a) image taken from the region near the surface of the specimen (b) image taken from the inner part of the specimen...

The structure of a foam, which deforms in a specific manner also influences physical properties. Upon initial compression there is a deformation of the structure that requires an increase in the amount of force applied. Once the foam has been deformed significantly the sides of the cell walls buckle leading to cell collapse and the production of elliptically deformed structures. A picture of such cells deformed under extreme compression is shown in Figure 14. During this phase of the compression the rate of increase in the force applied is significantly decreased. 

Side-chains could be added much more easily to structure I by permitting certain small deformations of the backbone structure, so allowed side-chains for a deformed structure I are also listed. 

Fleming P. D. (1996) Inherited deformation structures in metasedimentary enclaves in granites as windows into deeper levels of the crust. Tectonophysics 267, 177-185. 

Carson, B., von Huene, R. and Arthur, M. 1982. Small-scale deformation structures and physical properties related to convergence in Japan Trench slope sediments. Tectonics, 1 277-302. 

Sverdrup, E. and Prestholm, E. 1990. Synsedimentary deformation structures and their implications for stylolitization during deeper burial. Sedimentary Geol., 68 201-210. 

The structure of Immiscible blends Is seldom at equilibrium. In principle, the coarser the dispersion the less stable It Is. There are two aspects of stability Involved the coalescence In a static system and deformability due to flow. As discussed above the critical parameter for blend deformability Is the total strain In shear y = ty, or In extension, e = te. Provided t Is large enough In steady state the strains and deformations can be quite substantial one starts a test with one material and ends with another. This means that neither the steady state shearing nor elongatlonal flow can be used for characterization of materials with deformable structure. For these systems the only suitable method Is a low strain dynamic oscillatory test. The test Is simple and rapid, and a method of data evaluation leading to unambiguous determination of the state of miscibility is discussed in a later chapter. 

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