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Subject oscillators

Scott S K 1994 Oscillations, Waves and Chaos in Chemical Kinetics (Oxford Oxford University Press) A short, final-year undergraduate level introduction to the subject. [Pg.1118]

This expression shows diat if die detuning Acuj is negative (i.e. red detuned from resonance), dieii die cooling force will oppose die motion and be proportional to die atomic velocity. The one-diniensional motion of die atom, subject to an opposing force proportional to its velocity, is described by a damped haniionic oscillator. The Doppler damping or friction coefficient is die proportionality factor. [Pg.2461]

Calculations within tire framework of a reaction coordinate degrees of freedom coupled to a batli of oscillators (solvent) suggest tliat coherent oscillations in the electronic-state populations of an electron-transfer reaction in a polar solvent can be induced by subjecting tire system to a sequence of monocliromatic laser pulses on tire picosecond time scale. The ability to tailor electron transfer by such light fields is an ongoing area of interest [511 (figure C3.2.14). [Pg.2987]

With tlie development of femtosecond laser teclmology it has become possible to observe in resonance energy transfer some apparent manifestations of tire coupling between nuclear and electronic motions. For example in photosyntlietic preparations such as light-harvesting antennae and reaction centres [32, 46, 47 and 49] such observations are believed to result eitlier from oscillations between tire coupled excitonic levels of dimers (generally multimers), or tire nuclear motions of tire cliromophores. This is a subject tliat is still very much open to debate, and for extensive discussion we refer tire reader for example to [46, 47, 50, 51 and 55]. A simplified view of tire subject can nonetlieless be obtained from tire following semiclassical picture. [Pg.3027]

Using MMd. calculate A H and. V leading to ATT and t his reaction has been the subject of computational studies (Kar, Len/ and Vaughan, 1994) and experimental studies by Akimoto et al, (Akimoto, Sprung, and Pitts. 1972) and by Kapej n et al, (Kapeijn, van der Steen, and Mol, 198.V), Quantum mechanical systems, including the quantum harmonic oscillator, will be treated in more detail in later chapters. [Pg.164]

Therefore, in the RF mode, ions transmitted through the rod guide are subjected to (1) an oscillation in step with the variations of the RF field in the x,y-plane, (2) a drift or guided motion caused by the inhomogeneity of the RF field (x,y-plane), and (3) a forward motion (z-direction) due to any initial velocity of the ions on first entering the rod assembly. The separate motions... [Pg.380]

Free- Vibration Methods. Free-vibration instmments subject a specimen to a displacement and allow it to vibrate freely. The oscillations are monitored for frequency and damping characteristics as they disappear. The displacement is repeated again and again as the specimen is heated or cooled. The results are used to calculate storage and loss modulus data. The torsional pendulum and torsional braid analy2er (TBA) are examples of free-vibration instmments. [Pg.197]

The most general problem should be that of a particle in a nonseparable potential, linearly coupled to an oscillator heat bath, when the dynamics of the particle in the classically accessible region is subject to friction forces due to the bath. However, this multidimensional quantum Kramers problem has not been explored as yet. [Pg.11]

Greases are also made from soaps of strontium, barium and aluminum. Of these, aluminum-based grease is the most widely used. It is insoluble in water and very adhesive to metal. Its widest application is in the lubrication of vehicle chassis. In industry, it is used for rolling-mill applications and for the lubrication of cams and other equipment subject to violent oscillation and vibration, where its adhesiveness is an asset. [Pg.879]

Uhlig, Tierney and McClelland S measured fretting damage by mass loss of recessed 25-4 mm diameter steel cylinders subjected to radial oscillating motion. The specimens were loaded pneumatically, frequency was varied. [Pg.1057]

It is left to reader to verify that, under Lee .s discrete mechanics, both free particles and particles subjected to a constant force, behave in essentially the sa e way as they do under continuous equations of motion. Moreover, the time intervals At = t-i i — ti are all equal. While the spatial behavior for non-constant forces (ex particles in a harmonic oscillator V potential) also remains essentially... [Pg.656]

It is clear that if the pendulum oscillates, the inductance L of the circuit is a function of the angle d, since the magnetic reluctance of the coil C varies because of the presence of the soft iron P. The first equation is the equation of an electric circuit to which is applied an e.m.f., E sin ad, subject to the condition that the inductance of this circuit is a function of d and has the frequency of the pendulum. [Pg.382]

These phenomena are being actively studied at the present time, and constitute a new chapter in the theory of oscillations that is known as piecewise linear oscillations. There exists already a considerable literature on this subject in the theory of automatic control systems11-34 but the situation is far from being definitely settled. One can expect that these studies will eventually add another body of knowledge to the theory of oscillations, that will be concerned with nonanalytic oscillatory phenomena. [Pg.390]

The properties of the hydrogen molecule and molecule-ion which are the most accurately determined and which have also been the subject of theoretical investigation are ionization potentials, heats of dissociation, frequencies of nuclear oscillation, and moments of inertia. The experimental values of all of these quantities are usually obtained from spectroscopic data substantiation is in some cases provided by other experiments, such as thermochemical measurements, specific heats, etc. A review of the experimental values and comparison with some theoretical... [Pg.24]

The solution of Eqs. (11.15-11.17), subject to the conditions (11.24-11.26), determines the displacement of the interface in time, as well as the evolution of the velocity, pressure and temperature oscillations. [Pg.442]

Discussion. It is apparent from Table II and Figure 3 that even though the reactor has been subjected to very severe oscillatory conditions where the frequency of oscillation was low with respect to the hold-up time and the amplitudes of the functions large, the MWD s of the resulting polymers differ very little from those produced in the steady-flow steady-state. [Pg.262]

It is a pleasure for us who are friends, colleagues, and collaborators, to offer this contribution to a volume published in honor of Yngve Ohm s bS " birthday. For most of his career, Yngve has been interested in response properties of various systems to various probes, and we offer this contribution in that spirit. The Generalized Oscillator Strength, the subject of this paper, is the materials property that describes the response of a medium to swift particle, and thus, perhaps, an appropriate subject for this volume. Mostly, we are happy to take this opportunity to thank Yngve for his help, inspiration, and friendship over the years. [Pg.177]

In the presence of an acoustic velocih/ field, uj t) = ul cos o J), the flame front is subjected to an oscillating acceleration sm coJ). When this acceleration is oriented toward the burnt gas, then the amplitude of the cells will tend to decrease. When it is oriented toward the unburnt gas, the amplitude of the cells will tend to... [Pg.76]


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See also in sourсe #XX -- [ Pg.26 ]




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A Pair of Oscillators Subject to Stochastic Forces

One Oscillator Subject to Periodic Force

One Oscillator Subject to Stochastic Forces

Subject harmonic oscillator

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