What is b factor analysis?
B-factors, also known as temperature factors or atomic displacement parameters, are calculated parameters in X-ray crystal structures that reflect disorder of atoms from their ideal equilibrium positions due to both thermal motion and positional disorder.
What is isotropic B factor?
The “temperature factor” field in the ATOM records of PDB files normally contains the isotropic B-factor ( Figure 1) or B e q , the value that represents isotropic displacement of atoms that were described by anisotropic ADPs during refinement.
What does B Factor mean?
The temperature factor (also called the temperature value, B factor, B value, or Debye-Waller factor) is. “a factor that can be applied to the X-ray scattering term for each atom (or for groups of atoms) that describes the degree to which the electron density is spread out.
What is a good B factor?
In the 3 to 5 angstrom resolution range, isotropic atomic B-factors can be 100, 200 or greater. At higher resolution, B-factors from 20-100 are reasonable.
What is b factor in protein structure?
The term B-factor, sometimes called the Debye-Waller factor, temperature factor, or atomic displacement parameter, is used in protein crystallography to describe the attenuation of X-ray or neutron scattering caused by thermal motion.
What is average B factor?
In the highest resolution range (0.0–1.5 Å) and when all the atom types are considered together, the average B-factor at pcVol = 100% is only 25 Å2, while it is 80 Å2, in the lowest resolution range (3.3–4.0 Å).
What is B Factor oil and gas?
b-factor is the derivative of 1/D (D=Nominal Decline) with respect to time and has no dimension. In early times, one could fit a set of production data with almost any value of b, and every one seemed to be a good fit.
What is DI in Arps equation?
Di = Decline constant defined by Eq.
What is hyperbolic decline?
In hyperbolic decline as opposed to exponential decline (where the decline rate stays constant with time), the decline rate decreases as a function of the hyperbolic exponent with time.
What is b factor in decline curve?
b is the hyperbolic decline exponent and K is the proportionality constant. In Eq. (17.1) d is called decline factor that is a slope of the natural log of production rate versus time. The decline curve equations assume that production decline is proportional to reservoir pressure decline.