Disorder, measurement

Suhara T, Nakayama K, Inoue O Dj dopamine receptor binding in mood disorders measured by positron emission tomography. Psychopharmacology 106 14-18, 1992... 

Benkert O. Decreased benzodiazepine receptor binding in panic disorder measured by lOMAZENIL-SPECT. A preliminary report. Eur. Arch. Psychiatry Clin. Neurosci. 1994 244 49-51. 113. 

Kaschka W, Eeistel H, Ebert D. Reduced benzodiazepine receptor binding in panic disorders measured by iomazenil SPECT. J. Psychiatr. Res. 1995 29 427-434. 

In Fig. 11.5, the hydraulic permeability calculated with the correlation proposed in Sobera and Kleijn (2006) for two different values of disorder measure a as a function of solid volume fraction is presented. 

Hydraulic permeability f as a function of fibre volume fraction. Results of micro-scale model at two values of disorder measure (a) are verified against the literature and present numerical data. 

Helium diffraction is especially sensitive to surface order on an atomic scale. On scattering from a well-ordered single crystal surface nearly 15% of the scattered helium atoms appear in the specular helium beam whereas this fraction can drop to 1% when the surface is disordered. Measurements of the fraction of specularly scattered helium can therefore provide information on the degree of atomic disorder in the solid surface. 

In general, it is diflfieult to quantify stnietural properties of disordered matter via experimental probes as with x-ray or neutron seattering. Sueh probes measure statistieally averaged properties like the pair-correlation function, also ealled the radial distribution function. The pair-eorrelation fiinetion measures the average distribution of atoms from a partieular site. 

Unlike the solid state, the liquid state cannot be characterized by a static description. In a liquid, bonds break and refomi continuously as a fiinction of time. The quantum states in the liquid are similar to those in amorphous solids in the sense that the system is also disordered. The liquid state can be quantified only by considering some ensemble averaging and using statistical measures. For example, consider an elemental liquid. Just as for amorphous solids, one can ask what is the distribution of atoms at a given distance from a reference atom on average, i.e. the radial distribution function or the pair correlation function can also be defined for a liquid. In scattering experiments on liquids, a structure factor is measured. The radial distribution fiinction, g r), is related to the stnicture factor, S q), by... 

Free energy is related to two other energy quantities, the enthalpy (the heat of reaction measured at constant pressure) and the entropy. S. an energy term most simply visualised as a measure of the disorder of the system, the relationship for a reaction taking place under standard conditions being... 

Most chemistry students acquire a much better feel for entropy by considering it a measure of the amount of disorder in a system. For example, the fact that AS, is positive immediately makes sense, since the vapor phase is more disordered than the liquid. 

Global AMI.5 sun illumination of intensity 100 mW/cm ). The DOS (or defect) is found to be low with a dangling bond (DB) density, as measured by electron spin resonance (esr) of - 10 cm . The inherent disorder possessed by these materials manifests itself as band tails which emanate from the conduction and valence bands and are characterized by exponential tails with an energy of 25 and 45 meV, respectively the broader tail from the valence band provides for dispersive transport (shallow defect controlled) for holes with alow drift mobiUty of 10 cm /(s-V), whereas electrons exhibit nondispersive transport behavior with a higher mobiUty of - 1 cm /(s-V). Hence the material exhibits poor minority (hole) carrier transport with a diffusion length <0.5 //m, which puts a design limitation on electronic devices such as solar cells. 

Step 11. At this point a computer program refines the atomic parameters of the atoms that were assigned labels. The atomic parameters consist of the three position parameters x,j, and for each atom. Also one or six atomic displacement parameters that describe how the atom is "smeared" (due to thermal motion or disorder) are refined for each atom. The atomic parameters are varied so that the calculated reflection intensities are made to be as nearly equal as possible to the observed intensities. During this process, estimated phase angles are obtained for all of the reflections whose intensities were measured. A new three-dimensional electron density map is calculated using these calculated phase angles and the observed intensities. There is less false detail in this map than in the first map. 

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