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991.
对于微分同胚,横戴同宿点的存在蕴含Smale马蹄的存在,本证明了这一定理的逆定理成立,即Smale马蹄的存在也蕴含横同宿点的存在。 相似文献
992.
The Pancharatnam phase when an ideal cavity is filled with a Kerr-like medium and coupling is affected through a nondegenerate Raman two-photon process is studied. A careful investigation is made seeking exact results on the temporal evolution of atomic inversion and Pancharatnam phase. We invoke the mathematical notion of maximum variation of a function to construct a measure for Pancharatnam phase fluctuations. It is shown that Pancharatnam phase contains explicit information about the statistics of the field and atomic coherence, and is also shown that addition of the Kerr medium has an important effect on the properties of this phase. The results show that the effect of the Kerr medium changes the quasiperiod of the Pancharatnam phase evolution. The influence of Stark shift on the atomic inversion and the Pancharatnam phase in both presence and absence of the nonlinear medium is examined. General conclusions reached are illustrated by numerical results. 相似文献
993.
Mark Rubinstein Peter Lubitz Shu-Fan Cheng 《Journal of magnetism and magnetic materials》2000,210(1-3)
We have investigated the ferromagnetic resonance spectra of an exchange-biased Ni80Fe20/CoO bilayer between room temperature and 4 K. Primary attention has been paid to the effect of the antiferromagnetic CoO film on the temperature-dependent resonance field shift of the ferromagnetic Ni80Fe20 film with respect to that of an unbiased film. At low temperatures, the field shift with the magnetic field applied perpendicular to the plane was determined to be more than twice the magnitude of the parallel field shift, and of the same sign, while an unoxidized single ferromagnetic film has much smaller parallel and perpendicular low-temperature shifts (here defined with respect to room temperature) of opposite sign. This observation implies that the anisotropy axis can rotate with the applied field, provided that the primary cause of the anisotropy is the interaction between the adjacent ferromagnetic and antiferromagnetic films. Since the perpendicular shift is more than a factor of two larger than the parallel field shift, the rotatable anisotropy is, in fact, anisotropic in this bilayer. 相似文献
994.
A scheme of quantum network based on multiuser differential phase shift quantum key distribution system (DPS-QKD) is proposed. In this quantum network, arbitrary two users can achieve secret bits sharing by point-to-multipoint quantum key distribution and secret bits comparison. A protocol of secret bits sharing between arbitrary two users is presented. This network can implement secret bits distribution over 200 km with higher key generation rate by today's technologies. In theory, the capacity of user numbers in this network is unlimited. Hence, our proposed quantum network can serve for a metropolitan QKD network. A wide area QKD network can be constructed with this metropolitan QKD network. 相似文献
995.
Generation of self-oscillations from a singly resonant periodically poled potassium titanyl phosphate crystal frequency doubler 下载免费PDF全文
We report on the generation of self-oscillations from a continuously pumped singly resonant frequency doubler based on a periodically poled potassium titanyl phosphate crystal (PPKTP). The sustained square-wave and staircase curve of self-oscillations are obtained when the incident pump powers are below and above the threshold of subharmonic-pumped parametric oscillation (SPO), respectively. The self-oscillations can be explained by the competition between the phase shifts induced by cascading nonlinearity and thermal effect, and the influence of fundamental nonlinear phase shift by the generation of SPO. The simulation results are in good agreement with the experiment data. 相似文献
996.
997.
X.-M. Su P. Dong J.-Y. Gao K. Muraoka 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,12(1):193-196
Electromagnetically induced transparency in a non-uniform plasma is investigated. We discuss the possible frequency ranges
in which a weak beam below cutoff can propagate transparently in this plasma with the presence of a strong high frequency
field. We also analyze the effect of driving intensity on the frequency range of the probe.
Received 3 March 2000 and Received in final form 21 April 2000 相似文献
998.
999.
Hana Mlčochová Ratih Ratih Lenka Michalcová Hermann Wätzig Zdeněk Glatz Matthias Stein 《Electrophoresis》2022,43(16-17):1724-1734
In this study, two capillary electrophoresis–based ligand binding assays, namely, mobility shift affinity capillary electrophoresis (ms-ACE) and capillary electrophoresis-frontal analysis (CE-FA), were applied to determine binding parameters of human serum albumin toward small drugs under similar experimental conditions. The substances S-amlodipine (S-AML), lidocaine (LDC), l -tryptophan (l -TRP), carbamazepine (CBZ), ibuprofen (IBU), and R-verapamil (R-VPM) were used as the main binding partners. The scope of this comparative study was to estimate and compare both the assays in terms of their primary measure's precision and the reproducibility of the derived binding parameters. The effective mobility could be measured with pooled CV values between 0.55% and 7.6%. The precision of the r values was found in the range between 1.5% and 10%. Both assays were not universally applicable. The CE-FA assay could successfully be applied to measure the drugs IBU, CBZ, and LDC, and the interaction toward CBZ, S-AML, l -TRP, and R-VPM could be determined using ms-ACE. The average variabilities of the estimated binding constants were 64% and 67% for CE-FA and ms-ACE, respectively. 相似文献
1000.
Gildas Bertho Imed Eddine Oumezziane Cédric Caradeuc Louis Guibout Christine Balducci Laurence Dinan Pierre J. Dilda Serge Camelo René Lafont Nicolas Giraud 《Magnetic resonance in chemistry : MRC》2022,60(5):504-514
We report the analysis of complex samples obtained during the microwave irradiation/heating of norbixin, which has been identified as a potential therapeutic target for age-related macular degeneration (AMD). In this context, identifying the different isomers that are obtained during its degradation is of primary importance. However, this characterization is challenging because, on the one hand, some of these isomers are unstable, and on the other hand, the 1H spectra of these isomeric mixtures are poorly resolved. We could successfully apply 1D pure shift experiments to obtain ultrahigh-resolution 1H nuclear magnetic resonance (NMR) spectra of the norbixin isomer samples and exploit their information content to analyze complementary 2D NMR data and describe accurately their isomeric composition. 相似文献