Since we did not know that we were in NDT we were unaware of others in the field and felt it to be a rather new field, we felt like explorers For us it was new and we carried on for some time blissfully unaware that Prof. Hughes had demonstrated the effect almost 100 years before and Foerster had solved most of the practical problems more than a decade earlier. We only gradually became aware that we were not alone. [Pg.273]

While the result should not have very exact physical meaning, as an exercise, calculating the f potential of lithium ion, knowing that its equivalent conductivity is 39 cm /(eq)(ohm) in water at 25°C. [Pg.216]

Because of (equation Al.4.107) and because of the fact that / y aiid f z conumite with each other, we know that there exists a complete set of simultaneous eigenfimctions of Py-, Py, / y and ft. An eigenfiinction oi Py, P Y and P has the fonn... [Pg.166]

But by the Einstein relation we know that the energy of a single photon on frequency oi is given by jod, and hence the total energy in tire field is... [Pg.220]

An alternative perspective is as follows. A 5-frmction pulse in time has an infinitely broad frequency range. Thus, the pulse promotes transitions to all the excited-state vibrational eigenstates having good overlap (Franck-Condon factors) with the initial vibrational state. The pulse, by virtue of its coherence, in fact prepares a coherent superposition of all these excited-state vibrational eigenstates. From the earlier sections, we know that each of these eigenstates evolves with a different time-dependent phase factor, leading to coherent spatial translation of the wavepacket. [Pg.238]

The McMillan-Mayer theory allows us to develop a fomialism similar to that of a dilute interacting fluid for solute dispersed in the solvent provided that a sensible description of W can be given. At the Ihnit of dilution, when intersolute interactions can be neglected, we know that the chemical potential of a can be written as = W (a s) + IcT In where W(a s) is the potential of mean force for the interaction of a solute... [Pg.565]

Conceptually similar studies have since been carried out for the reaction of Ft atoms with Cl/Aii(l 11). More recently, quantum-state distributions have been obtamed for both the Ft + Cl/Aii(l 11)[, and M and Ft(D) + D (Ft)/Cii(l 11) systems. The results of these studies are in good qualitative agreement widi calculations. Even for the Ft(D) + D (Ft)/Cii(l 11) system [89], where we know that the incident atom caimot be significantly accommodated prior to reaction, reaction may not be direct. Detailed calculations yield much smaller cross sections for direct reaction than the overall experimental cross section, indicating that reaction may occur only after trapping of the incident atom [90]. [Pg.914]

If we think of as trial variational wavefimction for the Flamiltonian //, we know that... [Pg.2179]

The probability distribution functions shown in figure C3.3.11 are limited to events that leave the bath molecule vibrationally unexcited. Nevertheless, we know that the vibrations of the bath molecule are excited, albeit with low probability in collisions of the type being considered here. Figure C3.3.12 shows how these P(E, E ) distribution... [Pg.3012]

Again, we aheady know that the ADT becomes possible only when the tians-fonnation matrix A satisfy Eq. (63)... [Pg.68]

Now we can calculate the ground-state energy of H2. Here, we only use one basis function, the Is atomic orbital of hydrogen. By symmetry consideration, we know that the wave function of the H2 ground state is... [Pg.437]

Group IIB and know that this means the group of elements zine. cadmium and mercury, whilst Group IIA refers to the alkaline earth metals beryllium, magnesium, calcium, barium and strontium. [Pg.13]

Given the enormous number of resources for chemical information available, many researchers do not have the time to learn the details of the variotis systems, and they end up searching in only a few resources with which they are familiar. This is a dangerous approach Knowing that both fee and non-fee resources are available on the Internet and both hold the desired information, it is prudent to search non-fee systems first and then use proprietary databases to fill data gaps [49]. [Pg.271]

We know that every QSPR model is limited by tbe data set that is used for building the model. In order to examine the diversity of this data set (the Huuskonen... [Pg.500]

The date of this Appendix is given as May 1879, and we know that Maxwell had, at chat time, seen an abstract of Reynolds memoir [82]. [Pg.180]

The book is organised so that some of the techniques discussed in later chapters refer to material discussed earlier, though I have tried to make each chapter as independent of the ofhers as possible. Some readers may therefore be pleased to know that it is not essential to completely digest the chapters on quantum mechanics and molecular mechanics in order to read about methods for searching conformational space Readers with experience in one or more areas may, of course, wish to be more selective. [Pg.13]

Several questions present themselves immediately How good does the initial guess have to be How do we know that the procedure leads to better guesses, not worse How many steps (how long) will the procedure take How do we know when to stop These questions and others like them will play an important role in this book. You will not be surprised to leam that answers to questions like these vary from one problem to another and cannot be set down once and for all. Let us start with a famous problem in quantum mechanics blackbody radiation. [Pg.2]

The program in Problem 4 gives final values for the integral under the normal curve that are obviously too large. The last entr y is 0.5002, whereas, from the nature of the problem, we know that the integral cannot exceed 0.5000. Suggest a reason for this. [Pg.29]

Having detemiined A b and knowing that the gas constant R = 8.314JK from macroscopic measurements on gases, determine Avogadro s number L from the relationship... [Pg.75]

The integral of ati oddfutictioti over a symmetrical interval is zero because every eletuent on the left half of the interval is canceled by an ei]ual atid opposite elemetit oti the right. From this we know that all the constatits b = 0 in Hq, (4- 19b) atid the half-Fourier ficrici... [Pg.120]

Compute (LVIMX. Search on bonds. Setup bonds, select all and hit OK. Enter Job Name 1-butene and Run (Jininx. Yon will see the model being kicked" repeatedly, l.eft click outside of the GMMX Hun box. You should see 3 minimized and 3 found. We already know that there are only three con formers, two of which are degenerate hetice, because E un nuirn we know all the... [Pg.128]

In more complicated cases, we shall have to verify that the extremum is a minimum.) Once we know that a = me /Ti we can substitute it back into the energy equation and find... [Pg.181]

We do not know either side of Eq. (6-33), but we do know that E is to be minimized with respect to some minimization parameters. The only arbitrary parameters we have are the a and aa, which enter into the LCAO. Thus our normal equations are... [Pg.184]

We also know that exact atomic orbitals are orthonormal, that is, Sa = 1 and = 0 for an LCAO. If we assume that orthonormality is canied from an LCAO into the molecular orbital, then S = I and, from Eq. (7-17),... [Pg.206]

In this particular case, the calculations are completely symmetrical up to Eqs. (8-30). Evei ything we have said for a we can also say for p. At self-consistency, a = p so we can substitute a for p at any point in the iterative process, knowing that as we approach self-consistency for one, we approach the same self-consistent value for the other. [Pg.239]

Knowing that sin(0) vanishes at0=n7i, for n=l,2,3,..., (although the sin(nTi) function vanishes for n=0, this function vanishes for all x or y, and is therefore unacceptable because it represents zero probability density at all points in space) one concludes that the energies Ex and Ey can assume only values that obey ... [Pg.16]

What about the two degenerate eigenveetors v(l) and v(2) Are they also orthonormal So far, we know that these two eigenveetors have the strueture... [Pg.531]

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