Angle drop-off

Angle drop-off Rate of change (°/100 ft) of the inclination angle in the section of the wellbore that is decreasing toward vertical. 

As shown in Fig. 12.17, the deadtime transfer function has a flat L at 0 dB curve for all frequencies, but the phase angle drops off to minus infinity. The phase angle is down to —180° when the frequency is n/D. So the bigger the deadtime, the lower the frequency at which the phase angle drops off rapidly. 

Each pixel in an array sees the cold-shield aperture from a slightly different distance and angle. This introduces nonuniformity in the irradiance across the array even if the scene or target is perfectly uniform. This effect is often called the cosine-to-the-fourth effectbecmse the projected solid angle drops off approximately as cos" , where is... 

Wells may be drilled at a constant angle to the target or dropped off to a lower angle through the reservoir section. To build, maintain or drop the deviation angle stabilisers are run in the bottom hole assembly (Fig. 3.15). A change in deviation used to require a round trip to change the position of those stabilisers in the bottom hole assembly. In recent years, adjustable, hydraulically activated stabilisers have been developed. The... 

We have seen that partial reflection of an X-ray beam occurs from a surface at angles of incidence above (j> with the intensity dropping off rapidly with (j>. In fact partial or total reflection occurs at the interface between any two materials with different re-... 

The technique of Rietveld profile analysis has already been mentioned in the context of X-ray powder diffraction, but it was with neutron powder diffraction that this technique originated. The fact that the neutron scattering factors are almost invariant with smOA means that the intensity of the data does not drop off at high angles of 6 as is the case with X-ray patterns, and so a neutron powder pattern tends to yield up considerably more data. 

Fig. 2.7. Drop off of doubled extinction angle 2"/ during stress-relaxation after cessation of steady shear flow according to Wales (59). Measurements on the melt of a high-density polyethylene (Marlex 6002) at a measurement temperature of 147° C. Shear rate of the steady shear flow q = 0.06 sec-1...

If the number of residues per turn is not integral, then the diffraction pattern is much more complex. For example, a protein alpha helix has 3.6 residues per turn, which means 18 residues in five turns. The diffraction pattern for a discrete helix of simple objects (say, points) with these dimensions has layer lines at all spacings Z = (18m + 5a)/5P, where m and a are integers, and the diffraction pattern will repeat every 18 layer lines. But of course, protein alpha helix does not contain 3.6 simple points per turn, but instead 3.6 complex groups of atoms per turn. Combined with the rapid drop-off of diffraction intensity at higher diffraction angles, this makes for diffraction patterns that are too complex for detailed analysis. 

The decline in the performance of a 122-cm-long water heat pipe with the tilt angle from the horizontal is shown in Fig. 10-37 for heat pipes willi coarse, medium, and fine wicks. Note that for the horizontal case, the heat pipe with a coarse wick performs best, but the performance drops off sharply as the evaporator end is raised from the horizontal. The heat pipe with a fine wick does not perform as well in the horizontal position but maintains its level of performance greatly at tilted positions. It is clear from this figure that heat pipes that work against gravity must be equipped with fine wicks. Tlie heat removal capacities of various heat pipes are given in Table 10-6. 

As one moves in either direction from fhis angle, fhe noise level, in some cases, can drop off significanfly. For example, the overall SPL created by gas jet mixing can be reduced as much as 25 dB when one moves from an angle of maximum noise level to an angle directly behind the nozzle (180°). 

KeV, where tuning with respect to the critical angle is done for a Fe edge experiment, we see a large drop off in reflectivity with increasing incidence angle. This is due to the air/film and film/air interfaces (the close densities of polypropylene and water yield similar reflectivity functions for both interfaces) until beam penetration and reflectivity from the water/quartz interface takes effect. Finite thickness oscillations are... 

Allowable torque also limits screws to a maximum of 500-600 mm in diameter. Screw conveyors are used for nearly horizontal transport. While they are able to lift solids at an angle, the particles begin to fall back along the flights of the screw, and efficiency drops off rapidly as the slope increases. At an inclination of 15-20°, the capacity of a screw can be cut by 50%. Specially designed units can operate vertically. These can replace short elevators in small plants. 

If we plot, on the vertical axis, the values of force in the form Fjlnro cos S (Fig. IV.7) and plot, on the horizontal axis, the values of the angle a (see Fig. IV.6.a), we find that as the angle a is increased, the values calculated for the capillary forces will drop off (for given values of r, a, and 6). This also is in accord with Eq. (IV.37). 

It will be seen from these results that, as the wetting angle is increased, i.e., as the surface becomes more hydrophobic, the forces of adhesion drop off the particle diameter under these conditions determines how much the adhesive force drops off since these forces are calculated not for a single particle, but for 1 cm of dust-covered surface. 

Thus, both in the case of direct contact between surfaces and in the case of a water interlayer between the contiguous bodies, the forces of adhesion drop off as the wettability of the solids is reduced, i.e., as the contact angle is increased. 

The deposition and adhesion of dust particles oii cyHndrical and spherical surfaces takes place in a nonuniform manner. The number of deposited particles of loess dust and the particle diameter are shown as functions of the angle of incidence on a cylindrical surface in Fig. IX.5, for various flow velocities [254]. The number and the maximum size of the deposited particles both fall off as the angle is increased from 0 to 90. For an angle near zero, the flow velocity will be minimal, and hence particle detachment due to aerodynamic drag will be negligible. With an angle p close to 90°, the number of adherent particles will drop off appreciably since the obUque impact gives a rotary motion to the particles. 

The calculated and experimental results are very close to each other these results show, that as the angle between the surface and the flow axis is reduced, the limiting size of the area saturated with adherent particles will drop off. This trend provides confirmation for Eqs. (IX.46)-(IX.48). 

Dynamic stress relaxometer n. An instrument that measures the relaxation response of an elastomeric material to a prescribed shear deformation over a range of temperature. Basic elements of the instrument are a cone-shaped stator cavity and a conical rotor, both electrically heated. The sample is placed in the stator, which rises to a position to form a constant specimen thickness, forcing out the excess material. After heating to the desired temperature, the rotor is rotated quickly through a small angle, to a known shear deformation. The subsequent drop-off torque, which results from the relaxation of stress within the sample, is recorded over the time it takes for it to decay. 

Indeed, the neutralization of atomic ions in close proximity to a solid s surface as noted in LIES and INS does exhibit a velocity dependence (see for example Tully and Tolk 1977, Rabalais 1994 for further discussions). In accordance with theoretical studies, the neutralization rate appears to drop off in an exponential manner with increasing velocity. This is realized through measurements of ion yield variations as a function of the ion beam s energy and/or angle relative to the surface. Note The angle influences the emission velocity normal to the surface (Vj ) and hence the interaction time. 

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