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In the literature, there sometimes occur inaccurate statements about the validity of Stirling s approximation in connection with the validity of single atom chemistry. [Pg.195]

The two points do not seem to be directly interrelated. Notice that there is the Stirling s series — an asymptotic expansion of the logarithm of a factorial — written as  [Pg.196]

The Stirling s approximation consists in the first two terms Inn n Inn — n. Its absolute error increases with larger n. Hence, the approximation never becomes perfectly valid, though its relative error becomes negligible for numbers like Na-In the meantime, a few more terms of Eq. 6.1 yield enough precision to meet any practical demand. Already four terms give an error less than 1 /360n3 for In 1 = 0 it is less than 0.0023, for ln3 - less than 0.0001, etc. the relative error obviously decreases with n even faster. [Pg.196]

The present author believes that many practical problems can be illuminated and even solved with the use Monte Carlo simulations like those presented above in this section. The simulations are inherently probabilistic and can incorporate both thermodynamic and kinetic factors. The simulations do not provide formulae, but their great advantage is the possibility to take into account real experimental conditions. Simulations do not take any significant time, even on standard PC workstations. On the other hand, deriving analytical formulae as a rule requires assuming idealized experimental conditions, which are often far from reality. [Pg.196]


The diagonal terms (where i = j) need a little more consideration. They are taken to depend on the nature of the atom on which basis function Xi is centred, but they also depend on the namre of the neighbouring atoms. [Pg.139]

Therefore, the more the system is inhomogeneous the more considerable the damaging process is. [Pg.205]

Furthermore, ir-arene complexes of transition metals are seldom formed by the direct reaction of benzene with metal complexes. More usually, the syntheses require the formation of (often unstable) metal aryl complexes and these are then converted to ir-arene complexes. The analogous formation of w-adsorbed benzene at a metal surface via the initial formation of ff-adsorbcd phenyl, merits more consideration than it has yet been given. It is to be hoped that the recognition and study of structure-sensitive reactions will allow more exact definition of the sites responsible for catalytic activity at metal surfaces. The reactions of benzene, using suitably labeled materials, may prove to be useful probes for such studies. [Pg.154]

Study Protocols. Historically, the ferret has been used more often in teratology (Hoar, 1984), reproductive (Hoar, 1984), and acute safety studies than in repeated dose studies (4-52 weeks in duration). More consideration, however, is now being given to the use of the ferret in pivotal repeated-dose safety assessment testing (Thornton et al., 1979 Hart, 1986 Haggerty et al., 1989). [Pg.603]

Recently, the planar structures using bipolar current collection have received more consideration for SOFCs because of new gas sealing and fabrication techniques. [Pg.178]

In other words, some uncertainty in the data should not be used as an excuse for inaction. This approach is being given more consideration in Europe than in the United States. The approach gains credibility when one considers how its application years ago would have prevented the tragic effects of lead in gasoline and paint. [Pg.245]

Other methods exist and may deserve more consideration. [Pg.165]

Generally all of the staff in here as far as possible, if we are aware that there s a problem with drugs in the home, that we are a bit more considerate. [Pg.56]

Once again, it is important to recall that a complexing agent which undergoes protonation (unlike Cl ) requires more consideration. This is because the concentration of the non-protonated complexing species varies as the pH changes. An example would be the acetate ion C2 H3 O2 which protonates... [Pg.93]

The full potential of chemistry is far from being realized, however. There is no donbt that we can, for instance, make some molecules well there are more considerations (see fig 1.1). For many classes of molecules, synthesis has so far been ineffec-... [Pg.10]

Zachary Well, he was much older and he studied all the time and would not take her out and all that. She was much younger than him and he should have been more considerate. [Pg.288]

The best presentations come from serious consideration of audience. Experienced writers and speakers have a gut feel for their audiences and constantly adjust to audience needs, but the less experienced communicator has less of a feel and has to give more consideration to the approach chosen. To aid this process, it is helpful to prepare a short audience brief to help guide presentation planning for a particular audience. [Pg.76]

On, ok Chamois Leather—TIiIb article, takes its name from the skins of the chamois but, although the term is still retained, those of sheep, deer, lambs, and the tliin portion of split hides and skins, are now converted into it. It is different from any of the varieties hitherto described, bcoause neither tannin nor mineral matters enter Into its formation the conservation being entirely effected by means of oils and fats. Further, the finest, aB well as tire coarsest quality known as wash-leather, receive precisely the same treatment, and consequently the difference they present is owing to the circumstance, that the finest skins are chosen for tho former, whilst the inferior ones are mado into the latter. In the last, sixteenth, and earlier centuries, the trade in chamois leather was much more considerable than at prosent because, in those periods, it was extensively used for clothing, particularly in the armies. It is now, however, abandoned for this purpose, in consequence of its permeability, owing to which it readily absorbed moisture, and parted with it bnt slowly qualities which kept the wearer in continual. danger of cold and rheumatic complaints. [Pg.528]

In the early years of GC, more consideration was given to partition (GLC) than to adsorption (GSC) systems. For GLC, the mechanism of retention was well understood, all of the mathematics were derived, and the chromatographic peak shapes were symmetrical. At that time, GSC had been utilized only for the separation of permanent gases. In recent years much has been accomplished in the determination of thermodynamic parameters in GSC separations. Part of the reason for the upsurge of interest was due to the desire to predict sample separations at any temperature, since most GSC data was reported at only one temperature. [Pg.575]

Lastly, we may expect to see more consideration given to the allhydrocracking refinery. This type of refinery offers the advantages of simplicity, flexibility for producing gasoline, jet, and lubricating oils, and favorable environmental factors both within the refinery and in the marketplace. [Pg.135]


See other pages where More Considerations is mentioned: [Pg.288]    [Pg.32]    [Pg.1699]    [Pg.2230]    [Pg.392]    [Pg.325]    [Pg.269]    [Pg.53]    [Pg.74]    [Pg.214]    [Pg.84]    [Pg.175]    [Pg.211]    [Pg.439]    [Pg.98]    [Pg.23]    [Pg.6]    [Pg.536]    [Pg.65]    [Pg.73]    [Pg.437]    [Pg.157]    [Pg.178]    [Pg.359]    [Pg.61]    [Pg.193]    [Pg.277]    [Pg.355]    [Pg.853]    [Pg.863]    [Pg.141]    [Pg.113]    [Pg.85]    [Pg.1122]    [Pg.1440]   


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More Subtle Considerations

Some more general process design considerations

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