Geometry effects

Geometry effects. The term geometry refers to size and shape of source (point, parallel beam, disk, rectangular), size and shape of detector aperture (cylindrical, rectangular, etc.), and distance between source and detector. 

Source effects. The size and, in particular, the way the source is made may have an effect on the measurement. Whether the source is a solid material or a thin deposit evaporated on a metal foil may make a difference. The effect of source thickness is different on charged particles, gammas, and neutrons. 

Detector effects. The detector may affect the measurement in two ways. First, the size and thickness of the detector window (Fig. 8.1) determine how many particles enter the detector and how much energy they lose, as they traverse the window. Second, particles entering the detector will not necessarily be counted. The fraction of particles that is recorded depends on the efficiency of the detector (see Sec. 8.4.2). 

The geometry may affect the measurement in two ways. First, the medium between the source and the detector may scatter and may also absorb some particles. Second, the size and shape of the source and the detector and the distance between them determine what fraction of particles will enter the detector and have a chance to be counted. 

As the various geometric parameters are interrelated, unexpected correlations with the chemical shift can emerge. In PIB, the chemical shifts of the 

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The above procedure produces blast parameters applicable to a completely symmetrical blast wave, such as would result from the explosion of a hemispherical vessel placed directly on the ground. In practice, vessels are either spherical or cylindrical, and placed at some height above the ground. This influences blast parameters. To adjust for these geometry effects, and 7 are multiplied by some adjustment factors derived from experiments with high-explosive charges of various shapes. 

Step 2 Adjust Nondimensional Ps for Geometry Effects of Vessel Orientation. First calculate dimensionless overpressures, Ps for endpoint conditions, ps, without geometry adjustment using Equation 6.3.17 from Reference 5. 

Using Table 6.11 a in Reference 5, divide Ps by an estimated (assume 0.03 adjustment factor to get equivalent Ps since the geometry effects cause longer distances to the ps endpoint overpressure conditions. 

C NMR chemical shifts of a series of higher substituted a-vinyl substituted vinyl cations 24-27 were calculated to explore the sensitivity of the predicted isotropic shifts to electron correlation, basis set and geometry effects in differently substituted l,3-dienyl-2-cations.51... 

Hasemi, Y. and Tokunaga, T., Flame geometry effects on the buoyant plumes from turbulent diffusion flames, Combust. Sci. Technol., 1984, 40, 1-17. 

Coefficient of variation for dust (dry assay) and dust (wet assay) was 8.5 and 8.7%, respectively. The range of trash contents is about 50 compared to about four for dust content. As explained by Montalvo (12). differences in dust content by the dry and wet assay methods are a result of a geometry effect associated with the former technique and the variation of adhesion force of dust on cotton with environment. Only one airborne dust measurement was taken on five of the six cottons. 

The raw data from a tensile test are the load versus elongation measurements made by the load cell and the extensometer, respectively. To eliminate sample geometry effects, the extension is divided by the initial length to obtain the dimensionless strain (which is occasionally multiplied by 100 and reported as % elongation for samples... 

Ga(CH3)3 + AsH3 —> GaAs 195, 198 Two-dimensional, axisymmetric flow, mass- and heat-transfer analysis, reactor geometry effects, flow transitions, and mass-transport-limited growth. 

Fine Geometry Effects on Shielding, NMR Refinement of Diffraction Results. 

PH3 The standard PH3 molecule provides a simple example of molecular geometry effects on the CSA tensor. If PH3 maintains C3v there are only two variables that... 

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