DEPICT

Figure 5.37 depicts the basic set up of a wireline logging operation. A sonde is lowered downhole after the drill string has been removed. The sonde is connected via an insulated and reinforced electrical cable to a winch unit at the surface. At a speed of about 600m per hour the cable Is spooled upward and the sonde continuously records formation properties like natural gamma ray radiation, formation resistivity or formation density. The measured data is sent through the cable and is recorded and processed in a sophisticated logging unita the surface. Offshore, this unit will be located in a cabin, while on land it is truck mounted. In either situation data can be transmitted in real time via satellite to company headquarters if required. 

However, it is possible that friction events from rubbing between fractured surfaces can be generated at low load levels also during the loading part of the cycle. This is depicted in the two correlation plots of Figure 5. In the plot at the bottom, these events are marked with a rectangle. It was decided that in addition to the previous filter, another filter based in load level should be added. Acoustic emission events were thus accepted only if they occurred at a load higher than 85% of the maximum load level of the test. 

Additional assistance is provided by secondary modification options that allow among others for a depiction of the original signal, the reconstruction of the depiction of the impedance plane of the eddy-current signals or for modifications of phase, amplification or zero point virtually in real time. That way, once C-scan images have been recorded, they can now be evaluated as needed without having to repeat the test. 

For qualitative examinations of the inner cooling structures (blades and vanes) the transmission-thermography is used. The procedure is principly depicted in illustration 3. 

Consider a microtomographic system as depicted in Figure 1. It can be shown that in this geometry [6] the phase contrast signal is... 

On the 4a graph the spectrum of the signal for transmission distance of 8 mm in the area of the weld is depicted, the corresponding scheme of location of the probe is shown in Figure 3 a. 

There are a number of relatively simple experiments with soap films that illustrate beautifully some of the implications of the Young-Laplace equation. Two of these have already been mentioned. Neglecting gravitational effects, a film stretched across a frame as in Fig. II-1 will be planar because the pressure is the same as both sides of the film. The experiment depicted in Fig. II-2 illustrates the relation between the pressure inside a spherical soap bubble and its radius of curvature by attaching a manometer, AP could be measured directly. 

Figure III-l depicts a hypothetical system consisting of some liquid that fills a box having a sliding cover the material of the cover is such that the interfacial tension between it and the liquid is zero. If the cover is slid back so as to uncover an amount of surface dJl, the work required to do so will he ydSl. This is reversible work at constant pressure and temperature and thus gives the increase in free energy of the system (see Section XVII-12 for a more detailed discussion of the thermodynamics of surfaces).

The surface forces apparatus of crossed mica cylinders (Section VI-4D) has provided a unique measurement of friction on molecular scales. The apparatus is depicted in Fig. VI-3, and the first experiments involved imposing a variation or pulsing in the sepa-... 

Fig. XV-2. Adsorption loops in a cubic lattice. The diagrams depict the surface sites as seen from below. (From Ref. 4.)...

If we represent the /bond by a line with two open circles to denote the coordinates of the particle 1 and 2, then the first two virial coefficients can be depicted graphically as... 

Figure A3.10.8 Depiction of etching on a Si(lOO) surface, (a) A surface exposed to Br2 as well as electrons, ions and photons. Following etching, the surface either becomes highly anisotropic with deep etch pits (b), or more regular (c), depending on the relative desorption energies for different surface sites [28].

The first step consists of the molecular adsorption of CO. The second step is the dissociation of O2 to yield two adsorbed oxygen atoms. The third step is the reaction of an adsorbed CO molecule with an adsorbed oxygen atom to fonn a CO2 molecule that, at room temperature and higher, desorbs upon fomiation. To simplify matters, this desorption step is not included. This sequence of steps depicts a Langmuir-Hinshelwood mechanism, whereby reaction occurs between two adsorbed species (as opposed to an Eley-Rideal mechanism, whereby reaction occurs between one adsorbed species and one gas phase species). The role of surface science studies in fomuilating the CO oxidation mechanism was prominent. 

Figure A3,12.2(a) illnstrates the lifetime distribution of RRKM theory and shows random transitions among all states at some energy high enongh for eventual reaction (toward the right). In reality, transitions between quantum states (though coupled) are not equally probable some are more likely than others. Therefore, transitions between states mnst be snfficiently rapid and disorderly for the RRKM assumption to be mimicked, as qualitatively depicted in figure A3.12.2(b). The situation depicted in these figures, where a microcanonical ensemble exists at t = 0 and rapid IVR maintains its existence during the decomposition, is called intrinsic RRKM behaviour [9].

In the above discussion it was assumed that the barriers are low for transitions between the different confonnations of the fluxional molecule, as depicted in figure A3.12.5 and therefore the transitions occur on a timescale much shorter than the RRKM lifetime. This is the rapid IVR assumption of RRKM theory discussed in section A3.12.2. Accordingly, an initial microcanonical ensemble over all the confonnations decays exponentially. However, for some fluxional molecules, transitions between the different confonnations may be slower than the RRKM rate, giving rise to bottlenecks in the unimolecular dissociation [4, ]. The ensuing lifetime distribution, equation (A3.12.7), will be non-exponential, as is the case for intrinsic non-RRKM dynamics, for an mitial microcanonical ensemble of molecular states. 

The first classical trajectory study of iinimoleciilar decomposition and intramolecular motion for realistic anhannonic molecular Hamiltonians was perfonned by Bunker [12,13], Both intrinsic RRKM and non-RRKM dynamics was observed in these studies. Since this pioneering work, there have been numerous additional studies [9,k7,30,M,M, ai d from which two distinct types of intramolecular motion, chaotic and quasiperiodic [14], have been identified. Both are depicted in figure A3,12,7. Chaotic vibrational motion is not regular as predicted by tire nonnal-mode model and, instead, there is energy transfer between the modes. If all the modes of the molecule participate in the chaotic motion and energy flow is sufficiently rapid, an initial microcanonical ensemble is maintained as the molecule dissociates and RRKM behaviour is observed [9], For non-random excitation initial apparent non-RRKM behaviour is observed, but at longer times a microcanonical ensemble of states is fonned and the probability of decomposition becomes that of RRKM theory. 

Figure B1.3.A.9. Diagram depicting the angles used in scattermg experiments employing linearly and circularly polarized light. The subscripts i and s refer to the incident and scattered beam respectively.

Figure Bl.4.3. (a) A schematic illustration of the THz emission spectrum of a dense molecular cloud core at 30 K and the atmospheric transmission from ground and airborne altitudes (adapted, with pennission, from [17]). (b) The results of 345 GHz molecular line surveys of tlu-ee cores in the W3 molecular cloud the graphics at left depict tire evolutionary state of the dense cores inferred from the molecular line data [21],...

Figure Bl.4.9. Top rotation-tunnelling hyperfine structure in one of the flipping inodes of (020)3 near 3 THz. The small splittings seen in the Q-branch transitions are induced by the bound-free hydrogen atom tiiimelling by the water monomers. Bottom the low-frequency torsional mode structure of the water duner spectrum, includmg a detailed comparison of theoretical calculations of the dynamics with those observed experimentally [ ]. The symbols next to the arrows depict the parallel (A k= 0) versus perpendicular (A = 1) nature of the selection rules in the pseudorotation manifold.

Figure Bl.11.7. chemical shifts in [10]-paracyclophane. They have values on either side of the 1.38 ppm found for large polymethylene rings and, thus, map the local shielding and deshielding near the aromatic moiety, as depicted in the upper part of the figure.

The mathematical description of the echo intensity as a fiinction of T2 and for a repeated spin-echo measurement has been calculated on the basis that the signal before one measurement cycle is exactly that at the end of the previous cycle. Under steady state conditions of repeated cycles, this must therefore equal the signal at the end of the measurement cycle itself For a spin-echo pulse sequence such as that depicted in Figure B 1.14.1 the echo magnetization is given by [17]... 

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