Specific coherent length

The important reasons for recent developments of this type of simulation are the following. First, the specific coherent length ( ,), represented as... 

London Bullion Market Association, silver specifications by, 22 649 London coherence length, 23 806 London equations, 23 806 London-Norris equations, 23 845 London penetration depth, 23 805, 806 London s forces, 12 4 15 213 21 602-604 ... 

To be specific, discussing T finite system of a large spherical size R , with having the meaning of the coherence length, we obtain... 

Graphite foam (product of Union Carbide) is uncompressed exfoliated graphite obtained at an intermediate stage of the production of Grafoil. The specific area is about 22 m /g. It can be regarded as a uniform powder with a coherence length of 900 100 A [39]. The density of foam is low, about 0.2 g/cm, and thus relatively large sample cells for adsorption studies are necessary. 

Substrate Specific Area (m"/g) Percentage of Isotropic Powder Percentage with Preferred Orientation Mosaic Spread FWHM (Degrees) Coherence Length (A) Density (g/cm )... 

This aspect of polymer-dopant interaction has been the subject of a more detailed study by Chen et al. [104]. PPV-Cs has been compared with rubidium-doped polyacetylene, for which the guest/host size ratio is very nearly the same (Table 1.7). Whereas poly-acetylene-Rb has an intrachannel coherence length of 25 A for the ion sublattice, the coiresponding value is 70 A in the case of PPV-Cs the ion siiblattices are incommensurate for both at the compositions studied. Such intriguing differences can only be understood by considering, in a more polymer-specific manner, the character of the chain and the guest-host interactions. 

The elastic moduli of an extruded PLC are largely determined by its molecular orientation, so we first consider the orientation parameters calculated from the observed meridional X-ray reflections. For liquid crystalline copolyesters and copolyesteramides, the sharpness of these reflections gives an indication of the coherence length, a value corresponding to 10 monomers being typical. Therefore, the orientation parameter obtained from the meridional reflection is not specific to the crystalline regions but instead reflects the average orientation of all the chains in the polymer. 

Mesoscopic materials form the subset of nanostructured materials for which the nanoscopic scale is large compared with the elementary constituents of the material, i. e. atoms, molecules, or the crystal lattice. For the specific property under consideration, these materials can be described in terms of continuous, homogeneous media on scales less than that of the nanostructure. The term mesoscopic is often reserved for electronic transport phenomena in systems structured on scales below the phase-coherence length A0 of the carriers. 

Boanini et al. [211] obtained Asp/HAp and L-glutamic acid/HAp composite nanocrystals, with an amino acid content up to 7.8 and 4.3 wt%, respectively, prepared by direct synthesis in aqueous medium. They found that incorporation of the amino acids (which occurs through a specific interaction with the HAp structure) affects the degree of crystallinity of the apatitic phase, which decreases as the amino acid content increases. The presence of amino acids controls the crystal dimensions and favours osteoblast proliferation, activation of their metabolism and differentiation, which is of high importance for potential biomedical applications. Direct synthesis of PAsp/HAp nanocrystals was performed and it was found that PAsp is quantitatively incorporated into HAp crystals, provoking a reduction of the coherent length of crystalline domains, as evidenced by WAXS and TEM observations [208]. 

From this framework, Werthamer and coworkers [70] developed a theoretical model in which the coherence length in the normal layer can be evaluated by replacing the bulk product vn /n with the bulk resistivity p and the coefficient of normal electronic specific heat y. Moreover, the theory was rearranged so that all the temperature-dependent terms were combined into a single term. Here, A is the temperature-independent coherence length wherein Tc is replaced by 7cs the transition temperature of the bulk superconductor. In the dirty limit, is replaced with n, and this model yields the expression... 

The coherence length is an important parameter that characterizes the behavior of superconductors. This is the length scale over which the paired carriers interact, or more specifically the size of the Cooper pair. One can make a rough estimate of this length from the uncertainty principle. If the binding energy of the Cooper pair is AE, we know the energy to this precision. Since... 

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