Angular measurement

The name degree centigrade was dropped in 1948 in favor of the degree Celsius because in some countries the grade has been used as a unit of angular measure. 

To begin with, we must specify the spectral window we are referring to and then use the appropriate detector telescope, radiotelescope or space-borne observatory. The next characteristic is the accuracy of the energy, frequency or wavelength measurement, followed by the accuracy of the angular measurement (resolving power), and the temporal resolution and sensitivity of the measurement. Finally, we note the direction, date and duration of the observation for each particular celestial object we choose to investigate. 

Anisotropic proton hyperfine couplings are measured by rotating the crystals in the external magnetic field. From hundreds of angular measurements various proton hyperfine couplings are obtained as follows. EPR data are analyzed using the spin Hamiltonian (A in MHz)... 

A unit of angular measurement such that there are 2 pi radians in a complete circle. One radian = 180/pi degrees. One radian is approximately 57.3°. radical axis... 

The term eentigrade should not be used beeause of possible eonfusion with the Freneh unit of angular measurement, the grade. 

Phase differences may be expressed in angular measure as well as in wavelength two rays, differing in path length by one whole wavelength, are said to differ in phase by 360°, or In radians. If the path difference is d, then the phase difference 0 in radians is given by... 

The use of angular measure is convenient because it makes the expression of phase differences independent of wavelength, whereas the use of a path difference to describe a phase difference is meaningless unless the wavelength is specified. 

Bodycomb J, Hara M. Light scattering study of ionomers in solution. 4. Angular measurements of sulfonated polystyrene ionomers in a polar solvent (dimethylformamide). Macromolecules 1994 27 7369-7377. 

Figure 6. The coordinate system applicable to angular measurements on self-supporting phyllo-sihcate films as used for micas (Cibin et al.

The repeated angular measurements on crystals of various forms had filled volumes. However, contrary to the views of Haiy concerning a close correspondence between crystalline form and chemical composition, these measurements brought no useful contribution to systematic mineralogy except for the possibility of verifying the existence of polymorphs and the presence of isomorphic series. 

One of the important attributes of synchrotron X-ray beams is that the radiation is horizontally polarized in the plane of the electron orbit (Koningsberger and Prins 1988 Hazemann et al. 1992). This property can be used to enhance the sensitivity of EXAFS to the various metal species tied up to layered minerals in performing angular measurements on textured samples. In P-EXAFS, the amplitude of the EXAFS contribution of an atomic shell S coordinated to an element E can be written in the plane wave approximation and at the E K-edge... 

All commercially available CD instruments measure AA = Al - Ar which is readily converted to Ae by Eq. (3). However, most instruments are calibrated in terms of molar ellipticity, an alternative measure of CD which is mainly of historical interest. The ellipticity is an angular measure which is related to AA as follows ... 

Stars exhibit the same phenomenon. As the earth orbits the sun nearby stars appear to move back and forth against the background of more distant stars. The parallax of the star is the half angle p which defines the shift of the star s apparent position viewed from opposite sides of the earth s orbit around the sun. To derive the distance d from the angular measurement it is necessary to know the distance between planet Earth and the sun, which defines the astronomical unit (All) of distance. If the angle p is measured in seconds of arc, the distance d, defined as... 

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