scholarly journals Three Dimensional Analytical Separation of Grain Boundary and Surface Scatterings in Polycrystalline Metal Films in the Case of Non Cubic Grains

1981 ◽  
Vol 9 (2) ◽  
pp. 125-130 ◽  
Author(s):  
C. R. Tellier ◽  
C. R. Pichard ◽  
A. J. Tosser
Keyword(s):  
Grain Boundaries ◽  
Three Dimensional ◽  
Approximate Model ◽  
Metal Films ◽  
Three Dimensional Model ◽  
Polycrystalline Metal ◽  
Fine Grained ◽  
Thin Polycrystalline ◽  
Analytical Separation ◽  
Approximate Expressions

Analytical approximate expressions for the resistivity and its temperature coefficient of thin polycrystalline metal films have been derived by considering separately the contributions of the grain-boundaries perpendicular to thex-,y- andz-axes. Provided that the grain-boundaries act as moderately efficient scatterers reasonable deviations from the three-dimensional model are obtained; an approximate model then seems convenient with which to perform the calculations of the strain coefficients of such fine-grained films.

Three-dimensional strain coefficients of resistivity of thin polycrystalline metal films

1981 ◽  
Vol 16 (8) ◽  
pp. 2281-2286 ◽  
Author(s):  
C. R. Tellier ◽  
C. R. Pichard ◽  
A. J. Tosser
Keyword(s):  
Three Dimensional ◽  
Metal Films ◽  
Polycrystalline Metal ◽  
Thin Polycrystalline

Experimental Test of a Three-Dimensional Model for Electrophysical Properties of Metal Films

2000 ◽  
Vol 39 (Part 2, No. 12B) ◽  
pp. L1320-L1323 ◽  
Author(s):  
Anatoly M. Chornous ◽  
Nadia M. Opanasyuk ◽  
Alexander D. Pogrebnjak ◽  
Ivan Yu. Protsenko
Keyword(s):  
Experimental Test ◽  
Three Dimensional ◽  
Metal Films ◽  
Electrophysical Properties ◽  
Dimensional Model ◽  
Three Dimensional Model

Morphology of escherichia coli ribosomes as obtained by high resolution shadow cast

1978 ◽  
Vol 36 (2) ◽  
pp. 240-241 ◽  
Author(s):  
B. Tesche ◽  
G.W. Tischendorf ◽  
G. Stöffler
Keyword(s):  
Freeze Drying ◽  
Three Dimensional ◽  
Optical Resolution ◽  
Single Particles ◽  
Three Dimensional Model ◽  
Rna Molecules ◽  
E Coli ◽  
Fine Grained ◽  
Shadow Casting ◽  
Shadow Cast

All components (54 proteins and 3 RNA molecules) of the E. coli ribosome have been identified and characterized by biochemical and biophysical means. The morphology of the ribosome and the structural arrangement of its components, however, is not yet unequivocally known. The reasons for this are that crystal arrangements could not be obtained and that the different preparations of single particles remain invariant; and that holds for different laboratories as well.We applied a preparation which has been demonstrated to be most gentle and hence most structure-preserving; that is, freeze-drying with shadow casting at -150°C. Furthermore, the evaporator is of such design that it produces very little heat and renders a thin, fine-grained tungsten layer. An electron optical resolution of 6 Å can be achieved. Fig. 1 shows a micrograph of a typical shadowgraph obtained with 70S ribosomes from which we attempt to derive a three-dimensional model of the ribosome.

Constrained minimal-interface structures in polycrystalline copper with extremely fine grains

Science ◽  
2020 ◽  
Vol 370 (6518) ◽  
pp. 831-836
Author(s):  
X. Y. Li ◽  
Z. H. Jin ◽  
X. Zhou ◽  
K. Lu
Keyword(s):  
Grain Boundaries ◽  
Pure Copper ◽  
Three Dimensional ◽  
Fine Grained ◽  
Grain Sizes ◽  
Equilibrium Melting Point ◽  
Polycrystalline Solids ◽  
Dynamics Simulations ◽  
Amorphous States ◽  
Interface Structures

Metals usually exist in the form of polycrystalline solids, which are thermodynamically unstable because of the presence of disordered grain boundaries. Grain boundaries tend to be eliminated through coarsening when heated or by transforming into metastable amorphous states when the grains are small enough. Through experiments and molecular dynamics simulations, we discovered a different type of metastable state for extremely fine-grained polycrystalline pure copper. After we reduced grain sizes to a few nanometers with straining, the grain boundaries in the polycrystals evolved into three-dimensional minimal-interface structures constrained by twin boundary networks. This polycrystalline structure that underlies what we call a Schwarz crystal is stable against grain coarsening, even when close to the equilibrium melting point. The polycrystalline samples also exhibit a strength in the vicinity of the theoretical value.

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