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Aitken form

This oscillation may have no relation at all to the behavior of the "true" function. Therefore, we cannot recommend global interpolation except for small samples. In large samples interpolation is rarely needed. For medium size samples low order local interpolation considering 3-6 nearest neighbors of the point x of interest does the job in most cases. The most popular method is local cubic interpolation in the Aitken form programmed in the following module. [Pg.227]

Aitken nuclei Particles, generally with diameters less than 0.1 xm, that are true aerosols when they form the nucleus for condensation or ice formation. [Pg.1413]

There is one method, however, of increasing the order of convergence, that is often extremely useful. In fact, it can be applied to an arbitrary sequence, however the sequence may have been derived it will often produce a sequence that converges more rapidly than the original, and will even, in many cases, produce a converging sequence out of one that diverges. It is due to Aitken, who called it the 82-process. Beginning with x0, let x and x2 be computed in the normal manner by Eq. (2-17), but then form x3 by... [Pg.80]

Nitrous acid is also employed as a nitrating agent in organic chemistry. Thus, M. F. Aitken and T. H. Reade studied its action on p-iododimethylaniline, and obtained nitro-derivatives J. Reilly and P. J. Drumm, its action on substituted p-phenylenediamines and F. Bettzieche, and R. H. A. Plimmer, its action on amides and other amino-compounds. Nitrogen trioxide was found by H. Reihlen and A, Hake to form att unstable complex with stannic chloride—possibly 38nCl4.4N02. Nitrogen trioxide reacts with stannic chloride not in the ordinary blue but in the colourless form. A. Klemenc and R. Scholler studied the partition of nitrous acid between ether and water. The poisonous qualities of nitrous acid have been discussed by A. Purcell,3 etc. [Pg.464]

Number concentration of particles between 30 and 50 nm of dry diameter (N30-50), given in particles per cubic centimeter (cm-3). These particles represent smaller end of the Aitken mode particles and are representative of recently emitted or formed nanoparticles, which have high probability to end up in... [Pg.299]

Recently, a fourth mode has been introduced into this nomenclature It appears that particles with sizes less than 0.1 pm consist of two modes, the nucleation mode, which includes particles with dae between 0.01 and 0.03 pm representing quite recently formed particles, and the Aitken mode containing particles between 0.03 and 0.1pm (Horvath, 2000). [Pg.454]

The intramolecular photodimerization and [2 + 2]-photocycloaddition in DNA involves thymine or cytosine as the chromophore. This chemistry has been intensively investigated with regards to DNA damage and repair [131]. Despite the fact that the area is of continuous interest [132], the synthetic applications are limited and are not covered here in detail. However, some preparative aspects of 4-pyrimidinone photocycloaddition chemistry will be addressed. Aitken et al. have prepared a plethora of constrained cyclobutane P-amino acids by intra- or intermolecular [2 + 2]-photocycloaddition to uracil and its derivatives [133, 134]. In a chiral adaptation of this method, the uracil-derived enone 140 was employed to prepare the diastereomeric cyclobutanes 141 in very good yield (Scheme 6.49). The compounds are easily separated and were - despite the relatively low auxiliary-induced diastereoselectivity - well suited to prepare the as-2-aminocyclobutanecarboxylic acids 142 in enantiomerically pure form. Enantioselective access to the corresponding trans-products was feasible by epimerization in a-position to the carboxyl group [135],... [Pg.200]

Early observations on the width of the dust-free space were made by Aitken (1884a, b) and Lodge and Clark (1884). Later Watson (1936) and Miyake (1935) developed an empirical formula which fit experimental observations that the dust-free space increases with increasing temperature of the body and decreasing air pressure, and decreases with increasing molecular weight of the surrounding gas. For example, Watson found an empirical relationship between the width in centimeters of the dust-free space adf and temperature in the form... [Pg.292]

Aitken, J.F., vanHeusden, G.P., Temkin, M., and Dowhan, W., 1990, The gene encoding the phosphatidylinositol transfer protein is essential for cell growth. J. Biol. Chem. 265 4711 —4717. Ambroziak, J., and Henry, S.A., 1994, IN02 and IN04 gene products, positive regulators of phospholipid biosynthesis in Saccharomyces cerevisiae, form a complex that binds to the INOl promoter. J. Biol. Chem. 269 15344-15349. [Pg.149]

The in situ produced aerosol has a characteristic bimodal distribution dS/dlgr. The first mode is determined by Aitken particles themselves (r < 0.1 pm). The second, coagulative mode (0.1 pm < r < 1 pm) is constantly supplied with heterogeneously coagulating Aitken particles and, for these particles, it is the last form of existence before the aerosol particles in question leave the atmosphere. The parameters of the coagulative mode are dg (mean geometrical diameter) = 0.37 pm, o = 2.00... [Pg.296]

Equation (3) 15.VIIIL, shows that the vapour pressure over a drop of radius r=0 should be infinite, and it is necessary to explain how very small drops can begin to form at all in clouds. Aitken showed that they probably form over... [Pg.370]

The Hadean impact record is best calibrated to the large lunar hasins (Zahnle Sleep 1996 Anbar et al. 2001). To order of magnitude, the mass of the typical basin-forming impactor was c. 10 g although the archtypes (e.g. Orien-tale) were larger, c. 10 g and the largest that remains clearly visible (S. Pole-Aitken), perhaps... [Pg.248]

Particles formed by the dispersal of surface materials generally have radii larger than about 0.1 /im. This means that Aitken-size particles must be produced by another mechanism, namely by condensation of vapours, preceded in many cases by gaseous chemical reactions. These reactions are generally initiated by photochemical processes. [Pg.99]

The third major class of analytical techniques may be called morphological methods. This identification consists of comparing the form of particles captured with the morphology of particles of known composition. It goes without saying that morphological similarity is a necessary but not always sufficient condition for compositional identity. In spite of this problem this procedure is widely employed mainly in clean atmosphere, since even Aitken size particles can be identified morphologically (A. Meszaros and Vissy, 1974 Butor, 1976). [Pg.114]

The sources and chemical compositions of the fine and coarse urban particles are different. Coarse particles are generated by mechanical processes and consist of soil dust, seasalt, fly ash, tire wear particles, and so on. Aitken and accumulation mode particles contain primary particles from combustion sources and secondary aerosol material (sulfate, nitrate, ammonium, secondary organics) formed by chemical reactions resulting in gas-to-particle conversion (see Chapters 10 and 14). [Pg.373]

The main mechanisms of transfer of particles from the Aitken to accumulation mode is coagulation (Chapter 13) and growth by condensation of vapors formed by chemical reactions (Chapter 12) onto existing particles. Coagulation among accumulation mode particles is a slow process and does not transfer particles to the coarse mode. [Pg.373]


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See also in sourсe #XX -- [ Pg.227 ]




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