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101.
Ferro-Luzzi M Bouwhuis M Passchier E Zhou Z Alarcon R Anghinolfi M van Bommel R Botto T van den Brand JF Buchholz M Bulten HJ Choi S Comfort J Dolfini S Ent R Gaulard C Higinbotham D de Jager CW van Klaveren EP Konstantinov E Lang J de Lange DJ Miller MA Nikolenko D Nooren GJ Papadakis N Passchier I Poolman HR Popov SG Rachek I Ripani M Six E Steijger JJ Taiuti M Unal O Vodanis N de Vries H 《Physical review letters》1996,77(13):2630-2633
102.
Márcio José Horta Dantas Rubens Sampaio Roberta Lima 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2016,67(1):2
In this work a class of time-periodic electromechanical system is investigated. This system is nonhyperbolic. By using Regular Perturbation Theory, results on existence and stability of periodic orbits are obtained. Moreover, the dynamics of this system can be approached in a mathematically rigorous way. These results generalize previous ones obtained for autonomous electromechanical systems. 相似文献
103.
Hansen AK Almagri AF Craig D Den Hartog DJ Hegna CC Prager SC Sarff JS 《Physical review letters》2000,85(16):3408-3411
A cause of observed anomalous plasma momentum transport in a reversed-field pinch is determined experimentally. Magnetohydrodynamic theory predicts that nonlinear interactions involving triplets of tearing modes produce internal torques that redistribute momentum. Evidence for the nonlinear torque is acquired by detecting the correlation of momentum redistribution with the mode triplets, with the elimination of one of the modes in the triplet, and with the external driving of one of the modes. 相似文献
104.
Lanier NE Craig D Anderson JK Biewer TM Chapman BE Den Hartog DJ Forest CB Prager SC Brower DL Jiang Y 《Physical review letters》2000,84(10):2120-2123
Contrary to what has been observed thus far collision-induced light scattering (CILS) can be completely polarized. This exceptional behavior characterizes the very far wing of the binary CILS spectrum by gaseous helium. This conclusion is drawn from an experimental study of the depolarization ratio of He (2) in a much extended, previously unexplored, spectral domain. Our analysis shows that this property, unique thus far, is mainly due to an almost perfect cancellation between polarization and exchange pair polarizability contributions to the depolarized spectrum, taking place at internuclear distances shorter than the atomic diameter. 相似文献
105.
Suppose that a consistent one-step numerical method of orderr is applied to a smooth system of ordinary differential equations.Given any integer m 1, the method may be shown to be of orderr + m as an approximation to a certain modified equation. Ifthe method and the system have a particular qualitative propertythen it is important to determine whether the modified equationsinherit this property. In this article, a technique is introducedfor proving that the modified equations inherit qualitativeproperties from the method and the underlying system. The techniqueuses a straightforward contradiction argument applicable toarbitrary one-step methods and does not rely on the detailedstructure of associated power series expansions. Hence the conclusionsapply, but are not restricted, to the case of Runge-Kutte methods.The new approach unifies and extends results of this type thathave been derived by other means: results are presented forintegral preservation, reversibility, inheritance of fixed points.Hamiltonian problems and volume preservation. The techniquealso applies when the system has an integral that the methodpreserves not exactly, but to order greater than r. Finally,a negative result is obtained by considering a gradient systemand gradient numerical method possessing a global property thatis not shared by the associated modified equations. 相似文献
106.
Ccopa Rivera E da Costa AC Lunelli BH Maciel MR Maciel Filho R 《Applied biochemistry and biotechnology》2008,148(1-3):163-173
In this work, a systematic method to support the building of bioprocess models through the use of different optimization techniques
is presented. The method was applied to a tower bioreactor for bioethanol production with immobilized cells of Saccharomyces cerevisiae. Specifically, a step-by-step procedure to the estimation problem is proposed. As the first step, the potential of global
searching of real-coded genetic algorithm (RGA) was applied for simultaneous estimation of the parameters. Subsequently, the
most significant parameters were identified using the Placket–Burman (PB) design. Finally, the quasi-Newton algorithm (QN)
was used for optimization of the most significant parameters, near the global optimum region, as the initial values were already
determined by the RGA global-searching algorithm. The results have shown that the performance of the estimation procedure
applied in a deterministic detailed model to describe the experimental data is improved using the proposed method (RGA–PB–QN)
in comparison with a model whose parameters were only optimized by RGA. 相似文献
107.
Pretreatment procedures of sugarcane bagasse with lime (calcium hydroxide) or alkaline hydrogen peroxide were evaluated and
compared. Analyses were performed using 2 × 2 × 2 factorial designs, with pretreatment time, temperature, and lime loading
and hydrogen peroxide concentration as factors. The responses evaluated were the yield of total reducing sugars (TRS) and
glucose released from pretreated bagasse after enzymatic hydrolysis. Experiments were performed using the bagasse as it comes
from an alcohol/sugar factory and bagasse in the size range of 0.248 to 1.397 mm (12–60 mesh). The results show that when
hexoses and pentoses are of interest, lime should be the pretreatment agent chosen, as high TRS yields are obtained for nonscreened
bagasse using 0.40 g lime/g dry biomass at 70 °C for 36 h. When the product of interest is glucose, the best results were
obtained with lime pretreatment of screened bagasse. However, the results for alkaline peroxide and lime pretreatments of
nonscreened bagasse are not very different. 相似文献
108.
Issa JP do Nascimento C Bentley MV Del Bel EA Iyomasa MM Sebald W de Albuquerque RF 《Micron (Oxford, England : 1993)》2008,39(4):373-379
This study evaluated the quantity and quality of newly formed bone, stimulated by rhBMP-2 in combination with monoolein or chitosan gel as carriers, in critical bone defects created in 36 Wistar rat mandibles. Two weeks after surgery, the animals were anesthetized with 37.5% urethane submitted to perfusion and the hemi-mandibles removed for histological and histomorphometrical analysis. The results showed that there was a statistical difference between groups of animals receiving or not rhBMP-2 (p<0.05). Newly formed bone was more intense in the occlusal region, followed by the basal and middle regions, respectively. Both carriers, monoolein and chitosan gels were adequate for defect filling and control of protein release. 相似文献
109.
This work discusses the entanglement and quantum polarization of superpositions of two-mode coherent states of the types |ψ1〉 = N1(|α, β〉 + |β, α〉) and |ψ2〉 = N2(|−α, −α〉 + |α, α〉). We use the concurrence to measure their entanglements and the quantum Stokes parameters and the Q function in order to analyze their polarization and degree of polarization. 相似文献
110.
Recent work has established a correspondence between the tripartite entanglement measure of three qubits and the macroscopic entropy of the four-dimensional 8-charge STU black hole of supergravity. Here we consider the configurations of intersecting D3-branes, whose wrapping around the six compact dimensions T6 provides the microscopic string-theoretic interpretation of the charges, and associate the three-qubit basis vectors |ABC>, (A, B, C=0 or 1) with the corresponding 8 wrapping cycles. In particular, we relate a well-known fact of quantum information theory, that the most general real three-qubit state can be parameterized by four real numbers and an angle, to a well-known fact of string theory, that the most general STU black hole can be described by four D3-branes intersecting at an angle. 相似文献