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  2. R-factor (crystallography) - Wikipedia

    en.wikipedia.org/wiki/R-factor_(crystallography)

    In the Cambridge Structural Database of small-molecule structures, more than 95% of the 500,000+ crystals have an R-factor lower than 0.15, and 9.5% have an R-factor lower than 0.03. Crystallographers also use the Free R-Factor ( R F r e e {\displaystyle R_{Free}} ) [ 3 ] to assess possible overmodeling of the data.

  3. Retardation factor - Wikipedia

    en.wikipedia.org/wiki/Retardation_factor

    An R F value will always be in the range 0 to 1; if the substance moves, it can only move in the direction of the solvent flow, and cannot move faster than the solvent. For example, if particular substance in an unknown mixture travels 2.5 cm and the solvent front travels 5.0 cm, the retardation factor would be 0.50.

  4. Reflectance - Wikipedia

    en.wikipedia.org/wiki/Reflectance

    m −1: Spectral radiant flux absorbed and scattered by a volume per unit length, divided by that received by that volume. Directional attenuation coefficient: μ Ω: m −1: Radiance absorbed and scattered by a volume per unit length, divided by that received by that volume. Spectral directional attenuation coefficient: μ Ω,ν μ Ω,λ: m −1

  5. Reflection coefficient - Wikipedia

    en.wikipedia.org/wiki/Reflection_coefficient

    In telecommunications and transmission line theory, the reflection coefficient is the ratio of the complex amplitude of the reflected wave to that of the incident wave. The voltage and current at any point along a transmission line can always be resolved into forward and reflected traveling waves given a specified reference impedance Z 0.

  6. Effective radiated power - Wikipedia

    en.wikipedia.org/wiki/Effective_radiated_power

    ERP < 22.77 dB W and EIRP < 24.92 dB W, both less than ideal by η in dB. Assuming that the receiver is in the first side-lobe of the transmitting antenna, and each value is further reduced by 7.2 dB, which is the decrease in directivity from the main to side-lobe of a Yagi–Uda.

  7. Permeability (electromagnetism) - Wikipedia

    en.wikipedia.org/wiki/Permeability...

    For example, 4% electrical steel has an initial relative permeability (at or near 0 T) of 2,000 and a maximum of 38,000 at T = 1 [5] [6] and different range of values at different percent of Si and manufacturing process, and, indeed, the relative permeability of any material at a sufficiently high field strength trends toward 1 (at magnetic ...

  8. X-ray fluorescence - Wikipedia

    en.wikipedia.org/wiki/X-ray_fluorescence

    In scientific methods that use X-ray/neutron or electron diffraction the before mentioned planes of a diffraction can be doubled to display higher order reflections. The given planes, resulting from Miller indices, can be calculated for a single crystal. The resulting values for h, k and l are then called Laue indices. So a single crystal can ...

  9. Extremely low frequency - Wikipedia

    en.wikipedia.org/wiki/Extremely_low_frequency

    For example, a 3 Hz signal has a wavelength equal to the distance electromagnetic waves travel through a given medium in one third of a second. When the refractive index of the medium is greater than one, ELF waves propagate slower than the speed of light in vacuum. As used in military applications, the wavelength is 299,792 km (186,282 mi) per ...