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Rough focus

Rough focus the light on the baseboard. It does not have to be sharply focused. [Pg.198]

Let us examine next the bifurcations of the system (11.5.1) in the multidimensional case. If Li < 0 (Fig. 11.5.4), then when // < 0, the equilibrium state O is stable (rough focus when p < 0, and a weak focus aX p = 0) and it attracts all trajectories in a small neighborhood of the origin. When > 0 the point O becomes a saddle-focus with a two-dimensional unstable manifold and an m-dimensional stable manifold. The edge of the unstable manifold is the stable periodic orbit which now attracts all trajectories, except those in the stable manifold of O. One multiplier of the periodic orbit was calculated in Theorem 11.1, this is po p) = 1 — 47r /a (0) -h o p). To find the others we... [Pg.235]

Fast transient studies are largely focused on elementary kinetic processes in atoms and molecules, i.e., on unimolecular and bimolecular reactions with first and second order kinetics, respectively (although confonnational heterogeneity in macromolecules may lead to the observation of more complicated unimolecular kinetics). Examples of fast thennally activated unimolecular processes include dissociation reactions in molecules as simple as diatomics, and isomerization and tautomerization reactions in polyatomic molecules. A very rough estimate of the minimum time scale required for an elementary unimolecular reaction may be obtained from the Arrhenius expression for the reaction rate constant, k = A. The quantity /cg T//i from transition state theory provides... [Pg.2947]

Generally, the models used for simulation of living polymers can be divided roughly into two classes, focused on static or dynamic properties of the LP or GM. The static models are mainly designed to study equilibrium conformational properties of the polymer chains, critical behavior at the polymerization transition, and molecular weight distribution... [Pg.511]

Before we examine the details of this rather strange looking equation, let us focus our attention on the + energy term. The numerical value is of the order of 4.5 X 109 kcal/mole of uranium. Look at that figure again and compare it to the molar heat of combustion of carbon. Roughly, what is the ratio of these two energies It is 107, or 10 million ... [Pg.120]

Most interest focuses on very fast reactions. This includes systems whose mean reaction times range from roughly 1 minute to 10 14 second. Reactions that involve bond making or breaking are not likely to occur in less than 10 13 second, since this is the scale of molecular vibrations. Some unimolecular electron transfer events may, however, occur more rapidly. [Pg.253]

In Chap. 3 the problems of single-phase flow are considered. Detailed data on flows of incompressible fluid and gas in smooth and rough micro-channels are presented. The chapter focuses on the transition from laminar to turbulent flow, and the thermal effects that cause oscillatory regimes. [Pg.3]

New questions have arisen in micro-scale flow and heat transfer. The review by Gad-el-Hak (1999) focused on the physical aspect of the breakdown of the Navier-Stokes equations. Mehendale et al. (1999) concluded that since the heat transfer coefficients were based on the inlet and/or outlet fluid temperatures, rather than on the bulk temperatures in almost all studies, comparison of conventional correlations is problematic. Palm (2001) also suggested several possible explanations for the deviations of micro-scale single-phase heat transfer from convectional theory, including surface roughness and entrance effects. [Pg.37]

The sample is measured with a confocal microscope, by using a chromatic coding of the height, and with a contact-less optical needle focused on the surface. We determine by this way the surface topography and its roughness. [Pg.120]

Ozin, Hanlan, and Power, using optical spectroscopy (49,121). In view of the marked temperature-effect observed for the cobalt system, we shall focus on this cluster system here. Evidence for cobalt-atom aggregation at the few-atom extreme first came from a comparison of the optical data for Co Ar — 1 10 mixtures recorded at 4.2 and 12 K (see Fig. 4). A differential of roughly 8 K in this cryogenic-temperature regime was sufficient to cause the dramatic appearance of an entirely new set of optical absorptions in the regions 320-340 and 270-280 nm (see Fig. 4). Matrix variation, from Ar, to Kr, to Xe, helped clarify atom-cluster, band-overlap problems (see Fig. 5). [Pg.87]

Figure 2 shows the brief principle of a laser-detected FFM. A sample is put on a piezoelectrical tube (PZT), which scans X, Y plane and controls the feedback of Z axis. The laser beam from a diode is focused on the mirror of the free end of a cantilever with lens, and the reflected beam falls on the center of a position-sensitive detector (PSD), a four-quadrant photodiode. When the sample contacts with the tip and relatively moves under the control of a computer, the reflected beam deflects and changes the position on the PSD due to the twist and deflection of the cantilever caused by the changes of surface roughness, friction force, and adhesive force between the sample and the tip. The extension and re-... [Pg.188]

Demming et al. [17], and compared it with their experimental results. The observed increase in Raman intensity by a factor of 15 within the laser focus of about 2 pm, corresponds to a maximum local enhancement at the center of the tip apex by a factor of about 12 000 under the assumption that the tip radius is 100 nm. More precisely, about 20% of the Raman intensity is considered to originate from an area with a radius of 14 nm under the tip, which is roughly equivalent to 400 molecules out of 2 X 10 in the total focused area. [Pg.9]

A major movement within the pulp and paper industry has been an increased focus on the use of recovered paper. Nearly 50% of paper is now recovered and used either as recycled paper or as products such as home insulation. Furthermore, recovered paper contributes to U.S. exports roughly ten million tons of recovered paper were exported in 2000.1... [Pg.862]


See other pages where Rough focus is mentioned: [Pg.522]    [Pg.900]    [Pg.522]    [Pg.900]    [Pg.294]    [Pg.369]    [Pg.2456]    [Pg.2488]    [Pg.813]    [Pg.199]    [Pg.139]    [Pg.552]    [Pg.365]    [Pg.421]    [Pg.529]    [Pg.656]    [Pg.18]    [Pg.297]    [Pg.704]    [Pg.198]    [Pg.329]    [Pg.991]    [Pg.94]    [Pg.444]    [Pg.122]    [Pg.48]    [Pg.694]    [Pg.598]    [Pg.21]    [Pg.82]    [Pg.162]    [Pg.4]    [Pg.119]    [Pg.178]    [Pg.40]    [Pg.31]    [Pg.106]    [Pg.27]    [Pg.29]   


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