Far-held

If separate blast sources are located close to one another, they may be initiated almost simultaneously. Coincidence of their blasts in the far-held cannot be ruled out, and their respective blasts should be superimposed. The safe and most conservative approach to this issue is to assume a maximum initial blast strength of 10 and to sum the combustion energy from each source in question. Further definition of this important issue, for instance, the determination of a minimum distance between potential blast sources for separate consideration of their individual blasts, is a factor in present research. 

Figure 1. Monochromatic two source interference (a) Young s points, (b) Michelson interferometer, (c) 3D representation of far-held interference fringes over all viewing angles showing both Michelson fringes at the poles and Young s fringes at the equator .

The coefficient Ce depends on Xr and is 0.17 for Xr = 0.2 for the empirical constants of Table 10.1 Zukoski [8] reports 0.21 and Ricou and Spalding [21] report 0.18. For the far-held, valid above the flame height, Heskestad [22] developed the empirical equation ... 

In general, the plume flow field is divided into the near-field, transition, and far-held regions [5]. The near-held region which is shown in Fig. 29.1 consists of a nearly inviscid jet core dominated by strong wave structures and a thin... 

Also, in the cold jet case, pressure profiles were measured to assess possible thrust penalty associated with the flow-induced resonance. Near-held pressure prohles, which are plotted in Fig. 29.11 for typical forced and natural cases, again show the faster growth associated with the excitation. In the far held, the static pressure became identical to the ambient pressure. To obtain the thrust force, far-held total pressure prohles were integrated over the jet cross-sectional area. The measurement at 18 exit diameters downstream for the excited case showed that there was a force deheit of about 8% compared to the natural case. This appears to be the maximum amount of thrust penalty caused by periodic impingement of shear how on the cavity trailing edge. 

Here the subscript oo represents a reference property at the inlet condition, which may be at the inlet manifold or the far-held value for semi-infinite situations. The simple power-law dependence follows from kinetic theory. Typically the temperature dependence for polyatomic gases is n 0.645 (Section 3.3). 

The initial hope for conducting polymers was that they would replace metals in applications as simple conductors. The interest for conducting coatings and radio-frequency shielding remains, but is so far held up by problems of instability and cost. Much work in this area is not published because it is carried out by the defence industries. 

In summary, the photon model proposed leads to an extended symmetric set of Maxwell s equations, that contains a magnetic source and a magnetic current, both of electric origin. Conventional Maxwell s equations appear as a limiting case in far-held with both JB 0, pw 0. 

Many variables used and phenomena described by fracture mechanics concepts depend on the history of loading (its rate, form and/or duration) and on the (physical and chemical) environment. Especially time-sensitive are the level of stored and dissipated energy, also in the region away from the crack tip (far held), the stress distribution in a cracked visco-elastic body, the development of a sub-critical defect into a stress-concentrating crack and the assessment of the effective size of it, especially in the presence of microyield. The role of time in the execution and analysis of impact and fatigue experiments as well as in dynamic fracture is rather evident. To take care of the specihcities of time-dependent, non-linearly deforming materials and of the evident effects of sample plasticity different criteria for crack instability and/or toughness characterization have been developed and appropriate corrections introduced into Eq. 3, which will be discussed in most contributions of this special Double Volume (Vol. 187 and 188). 

The two most important types of far-held optical microscopes shall be described here in brief the confocal and the wide-held conhguration. 

As a quantitative measure of the far-held performance, two quantities may be introduced. First of all, sensitivity enhancement factor (SEF), a ratio of resonance angle shift due to target analyte binding on a nanowire-based biosensor to that of a conventional SPR structure using a thin gold him with equal thickness, is defined as... 

Dictated by the diffraction limit of light, the lateral resolution of a far-held optical microscope is dehned as the smallest distance between two features that can still be resolved in the image and is given by Rayleigh criterion as [5]... 

Detecting single nano-objects in a far-held laser spot requires carefully optimized setups, discussed in several reviews and books [3, 19]. Hereafter, we assume ideal conditions, perfect optical elements (detectors, sources, hlters, etc.), to concentrate on the fundamental limitations to signal-to-noise ratio in optical single-molecule studies. We consider three main detection techniques applied to individual small absorbers, emitting or not photoluminescence direct absorption, huorescence and photothermal contrast. 

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