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991.
D. Michalska B. Hess Andes Jr. L. J. Schaad 《International journal of quantum chemistry》1986,29(5):1127-1137
The IR frequencies of cyclopropene and methylenecyclopropene were computed with inclusion of correlation (MP2 /6-31G*). These along with those of ethylene obtained earlier by Pople were compared with SCF results (DZ + P). It was found that the MP 2 frequencies agreed better with experiment, but that the order of the bands remained the same as those computed without correlation. 相似文献
992.
Sam B. Nadler Jr 《Topology and its Applications》2006,153(8):1279-1290
Types of spaces are given on which every local connectivity function is a connectivity function, a connected function, or a Darboux function. A complete determination such spaces is obtained when the spaces are assumed to be arc-like continua or circle-like continua. Results provide answers to a question asked by Stallings. 相似文献
993.
J. W. Eslick Jr H. N. Pham C. Radu A. Puri 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(3):553-562
In this paper, we revisit the problem of quantum entanglement in an
oscillating macroscopic mirror previously studied by Marshall et al. consisting
of a modified Michelson interferometer where one of the mirrors is free to
oscillate about its center of mass. A photon incident upon the oscillating
mirror becomes entangled with the mirror, driving the mirror into a
superposition of quantum states. Once the photon and mirror decouple, the
mirror returns to its initial state. The purpose of our investigations was
to optimize the parameter regime, taking into consideration the current
state of technology and the demands imposed by the need to maintain a stable
environment in the presence of thermal noise. Optimization should not demand
ultra-low temperatures and this is reflected in our results. Our results also
show that if the separation between states is maintained at 10-14 m, the mirror size is reduced, making it easier to induce superposition in
the mirror. The critical nature of mirror reflectivity and its connection to
cavity decay rate was also revealed by our investigations. The results
obtained through our investigations could be useful in quantum error
correction, where decoherence negatively affects the results of computations
performed by quantum computers. Finally, we note that we are only concerned
with an isolated system, where no losses to the external environment occur
and any decoherence that occurs within the system remains internal to the
system; that is, any mention of decoherence refers specifically to
recoverable decoherence. 相似文献
994.
995.
Fluorescence spectroscopy applied to orange trees 总被引:1,自引:0,他引:1
L. G. Marcassa M. C. G. Gasparoto J. Belasque Jr E. C. Lins F. Dias Nunes V. S. Bagnato 《Laser Physics》2006,16(5):884-888
In this work, we have applied laser-induced fluorescence spectroscopy to investigate biological processes in orange trees (Citrus aurantium L.). We have chosen to investigate water stress and Citrus Canker, which is a disease caused by the Xanthomonas axonopodis pv. citri bacteria. The fluorescence spectroscopy was investigated by using as an excitation source a 442-nm 15-mW HeCd gas multimode discharge laser and a 532-nm 10-mW Nd3+:YAG laser. The stress manifestation was detected by the variation of fluorescence ratios of the leaves at different wavelengths. The fluorescence ratios present a significant variation, showing the possibility to observe water stress by fluorescence spectrum. The Citrus Canker’s contaminated leaves were discriminated from the healthy leaves using a more complex analysis of the fluorescence spectra. However, we were unable to discriminate it from another disease, and new fluorescence experiments are planned for the future. 相似文献
996.
Elliptic flow is easy to compute in hydrodynamics. However experimentally it is obtained in an indirect way. The question we address in this paper is how comparable are these two approaches. For both cases, our study is done using the hydrodynamical code
NeXSPheRIO and simulating nuclear collisions at RHIC. 相似文献
997.
998.
O. Rodrigues Jr. R. C. L. Figueira I. I. L. Cunha 《Journal of Radioanalytical and Nuclear Chemistry》1997,222(1-2):209-213
The137Cs radionuclide dispersion in the marine environment through the compartmental model is reported. The model simulates the surface water contamination caused by routine or accidental radionuclide releases. For the simulation the OCEAN program was applied in the North Sea, near to Sellafield and adjacent areas, based on published transfer coefficient data. The results are in good agreement with the literature and the model developed can be applied to the brazilian coastal regions. 相似文献
999.
F. M. L. Almeida Jr. Y. A. Coutinho J. A. Martins Sim es P. P. Queiroz Filho C. M. Porto 《Physics letters. [Part B]》1997,400(3-4):331-334
We discuss the possibility of same-sign dileptons as a signature for Majorana neutrinos. The production mechanism is given by a single heavy neutrino production and decay pp → l±NX → l±l±X′. Cross section and distributions are presented for the LHC energies. 相似文献
1000.
We study the relationship between Maxwell and Dirac equations for a class of solutions of Maxwell equations that can represent purely electromagnetic particles. 相似文献