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991.
T. Letardi S. Bollanti P. Di Lazzaro F. Flora N. Lisi C. E. Zheng 《Il Nuovo Cimento D》1992,14(5):495-507
Summary Some limitation problems for gas discharge excimer lasers, when scaled to a high pulsed energy output with high repetition
rate are discussed. As an example, we present some experimental results obtained with an X-ray preionized (10×10×100) cm3 active volume, low-repetition-rate-operated gas discharge XeCl laser system.
ENEA student.
ENEA guest. 相似文献
992.
993.
A scenario is presented, in which the presence of a quantum critical point due to formation of incommensurate charge density waves accounts for the basic features of the high temperature superconducting cuprates, both in the normal and in the superconducting states. Specifically, the singular interaction arising close to this charge-driven quantum critical point gives rise to the non-Fermi liquid behavior universally found at optimal doping. This interaction is also responsible for d-wave Cooper pair formation with a superconducting critical temperature strongly dependent on doping in the overdoped region and with a plateau in the optimally doped region. In the underdoped region a temperature dependent pairing potential favors local pair formation without superconducting coherence, with a peculiar temperature dependence of the pseudogap and a non-trivial relation between the pairing temperature and the gap itself. This last property is in good qualitative agreement with so far unexplained features of the experiments. 相似文献
994.
Fausto Di Biase Bert Fischer Rü diger L. Urbanke 《Proceedings of the American Mathematical Society》1998,126(5):1487-1490
It is known that the set of twist points in the boundary of the von Koch snowflake domain has full harmonic measure. We provide a new, simple proof, based on the doubling property of the harmonic measure, and on the existence of an equivalent measure, invariant and ergodic with respect to the shift.
995.
996.
M. Campostrini A. Di Giacomo Ŝ. Olejník 《Zeitschrift fur Physik C Particles and Fields》1986,31(4):577-582
We compute the effect of the gluon condensate on the spectra of heavy quarkonia, taking into account the condensate correlation length. We compare the results obtained for the hydrogen-like model with a more realistic model. The effects are shown to be very small both in bottomonium and toponium. 相似文献
997.
在运用数理统计方法分析实际数据的基础上,结合国内外的已有研究结果,初步认为在自行车流量小的情况下,泊松分布比较适用于描述自行车到达量的统计分布;而当自行车流量很大时,负二项分布比较适合描述一定条件下的自行车到达量的统计分布.考虑到自行车到达分布的复杂性,文中借鉴知识推理的一些概念和方法,非精确地描述了自行车到达分布规律. 相似文献
998.
A. De Michele K. Bousbahi G. Carelli A. Moretti 《International Journal of Infrared and Millimeter Waves》2003,24(10):1649-1654
We have investigated CHD2OH methanol as source of far-infrared (FIR) laser radiation using the optical pumping technique. Our new waveguide pulsed CO2 laser, with peak powers as high as some kW, has allowed us to observe 12 new lines. Each of them is characterized in wavelength, relative polarization, intensity, optimum operating pressure and pump offset from the center of the exciting CO2 line. 相似文献
999.
We consider a quantum integrable inhomogeneous model based on the Brauer algebra B(1) and discuss the properties of its ground state eigenvector. In particular we derive various sum rules, and show how some
of its entries are related to multidegrees of algebraic varieties. 相似文献
1000.
Yingwei Di Salvatore Iannace Ernesto Di Maio Luigi Nicolais 《Journal of Polymer Science.Polymer Physics》2003,41(7):670-678
Nanocomposites based on biodegradable polycaprolactone (PCL) and organically modified layered silicates (organoclay) were prepared by melt mixing. Their structures and properties were characterized by wide‐angle X‐ray diffraction, thermal analysis, and rheological measurements. The exfoliation of the organoclay was achieved via a melt mixing process in an internal mixer and showed a dependence on the type of organic modifier, the organoclay contents, and the processing temperature. The addition of the organoclay to PCL increased the crystallization temperature of PCL, but a high content of the organoclay could show an inverse effect. The PCL/organoclay nanocomposites showed a significant enhancement in their mechanical properties and thermal stability due to the exfoliation of the organoclay. The nanocomposites showed a much higher complex viscosity than the neat PCL and significant shear‐thinning behavior in the low frequency range. The shear storage modulus and loss modulus of the nanocomposites also exhibited less frequency dependence than the pure PCL in the low frequency range, and this was caused by the strong interactions between the organoclay layers and PCL molecules and by the good dispersion of exfoliated organoclay platelets in the PCL. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 670–678, 2003 相似文献