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141.
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Yunping Jiang Takehiko Morita Dennis Sullivan 《Communications in Mathematical Physics》1992,144(3):509-520
We prove that the period doubling operator has an expanding direction at the fixed point. We use the induced operator, a Perron-Frobenius type operator, to study the linearization of the period doubling operator at its fixed point. We then use a sequence of linear operators with finite ranks to study this induced operator. The proof is constructive. One can calculate the expanding direction and the rate of expansion of the period doubling operator at the fixed point. 相似文献
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Barrette J Bellwied R Braun-Munzinger P Cleland WE David G Duek E Fatyga M Fox D Gavron A Greene SV Hall J Hemmick TK Heifetz R Herman M Herrmann N Hogue RW Ingold G Jayananda K Kraus D Lissauer D Llope WJ Legault A Ludlam T Majka R Makowiecki D Mark SK Mitchell JT Muthuswamy M O'Brien E Olsen L Polychronakos V Rawool-Sullivan M Rotondo F Sandweiss J Shivakumar B Simon J Sonnadara U Sullivan JP Stachel J Sunier J Takai H Throwe T Van Hecke H Waters L Woody C Wolf K Wolfe D 《Physical review letters》1990,64(11):1219-1222
148.
The new type of boosted-output atomic spectral lamp described has a readily-interchangeable cathode that requires only a small quantity of pure material. The direction of argon flow-through is designed to enable the lamp to be used with cathodes of relatively volatile elements such as arsenic and selenium, without the element being deposited on the exit window. The high numerical aperture of the lamp makes it suitable for use in atomic fluorescence spectrometry. Its warm-up time is faster than that of commercially-available electrodeless discharge lamps and its performance in flame atomic fluorescence at least as good. For less-volatile metals the performance is equal to that of earlier types of demountable boosted-output lamp. 相似文献
149.
LetM be a complete Riemannian surface with constant curvature –1, infinite volume, and a finitely generated fundamental group. Denote by (M) the lowest eigenvalue of the Laplacian onM, and let
M
be the associated eigenfunction. We estimate the size of (M) and the shape of
M
by a finite procedure which has an electrical circuit analogue. Using the Margulis lemma, we decomposeM into its thick and thin parts. On the compact thick components, we show that
M
varies from a constant value by no more thanO(
). The estimate for (M) is calculable in terms of the topology ofM and the lengths of short geodesics ofM. An analogous theorem of the compact case was treated in [SWY]. 相似文献
150.
The primary relaxation time scale tau(T) derived from the glass forming supercooled liquids (SCLs) is discussed within ergodic-cluster Gaussian statistics, theoretically justified near and above the glass-transformation temperature T(g). An analysis is given for the temperature-derivative data by Stickel et al. on the steepness and the curvature of tau(T). Near the mode-coupling-theory (MCT) crossover T(c), these derivatives separate by a kink and a jump, respectively, the moderately and strongly SCL states. After accounting for the kink and the jump, the steepness remains a piecewise conitnuous function, a material-independent equation for the three fundamental characteristic temperatures, T(g), T(c), and the Vogel-Fulcher-Tamman (VFT) T(0), is found. Both states are described within the heterostructured model of solidlike clusters parametrized in a self-consistent manner by a minimum set of observable parameters: the fragility index, the MCT slowing-down exponent, and the chemical excess potential of Adam and Gibbs model (AGM). Below the Arrhenius temperature, the dynamically and thermodynamically stabilized clusters emerge with a size of around of seven to nine and two to three molecules above and close to T(g) and T(c), respectively. On cooling, the main transformation of the moderately into the strongly supercooled state is due to rebuilding of the cluster structure, and is attributed to its rigidity, introduced through the cluster compressibility. It is shown that the validity of the dynamic AGM (dynamically equivalent to the standard VFT form) is limited by the strongly supercooled state (T(g) < T < T(c)) where the superrigid cooperative rearranging regions are shown to be well-chosen parametrized solidlike clusters. Extension of the basic parameter set by the observable kinetic and diffusive exponents results in prediction of a subdiffusion relaxation regime in SCLs that is distinct from that established for amorphous polymers. 相似文献