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91.
The carrier-envelope phase of the pulse train emitted by a 10-fs mode-locked laser has been stabilized such that carrier-envelope phase coherence is maintained for at least 150 s (measurement limited). The phase coherence time was measured independently of the feedback loop. 相似文献
92.
Rahul Pandit Samriddhi Sankar Ray Dhrubaditya Mitra 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,64(3-4):463-469
We give an overview of the progress that has been made in recent years in understanding dynamic multiscaling in homogeneous, isotropic turbulence and related problems. We emphasise the similarity of this problem with the dynamic scaling of time-dependent correlation functions in the vicinity of a critical point in, e.g., a spin system. The universality of dynamic-multiscaling exponents in fluid turbulence is explored by detailed simulations of the GOY shell model for fluid turbulence. 相似文献
93.
Craig F Ferris Tara Stolberg Praveen Kulkarni Murali Murugavel Robert Blanchard D Caroline Blanchard Marcelo Febo Mathew Brevard Neal G Simon 《BMC neuroscience》2008,9(1):111
Background
With the advent of functional magnetic resonance imaging (fMRI) in awake animals it is possible to resolve patterns of neuronal activity across the entire brain with high spatial and temporal resolution. Synchronized changes in neuronal activity across multiple brain areas can be viewed as functional neuroanatomical circuits coordinating the thoughts, memories and emotions for particular behaviors. To this end, fMRI in conscious rats combined with 3D computational analysis was used to identifying the putative distributed neural circuit involved in aggressive motivation and how this circuit is affected by drugs that block aggressive behavior. 相似文献94.
95.
Phonon anomalies in two intermediate valence compounds (IVC), SmS and Sm0·75Y0·25S have been investigated using breathing shell model (BSM). The BSM includes breathing motion of electron shells of the rare
earth atom due tof−d hybridization. The phonon dispersion curves of IVC, calculated from the present model, agree well with the measured data.
One-phonon density of states calculated from the present model compares well with the Raman spectra. 相似文献
96.
Sankar P. Sanyal 《Journal of Physics and Chemistry of Solids》1981,42(5):429-432
A detailed investigation of the phonon dispersion and static and anharmonic properties has been carried out for ND4I using an extended three-body force shell model (ETSM) developed by Singh and Chandra. The ETSM results for phonon dispersion show better agreement with the experimental data than those obtained from the deformation dipole and rigid shell models. Calculated values have also been obtained for some other properties. 相似文献
97.
H. Huang B. P. Pathak R. Iafigliola L. Lessard J. K. P. Lee 《Zeitschrift für Physik A Hadrons and Nuclei》1977,282(3):285-292
The decay of mass separated90Rb has been studied usingβ,γ and conversion electron spectrometers in single and coincidence modes. The half-lives of the ground state and the isomeric level have been confirmed to be 162± 3 and 258±4 s, respectively. Theγ-rays from the decays of ground state and metastable state have been identified by measuring the decay of individual photopeaks using Ge(Li) detectors. The multipolarity of the 106.6 keV isomeric transition has been determined to beM3. Separate decay schemes of the ground and metastable states are presented. The levels of90Sr are discussed in terms of the available experimental and theoretical information. Radioactivity.90m,gRb [from238U(p, f)]; measuredT 1/2,E γ,I γ,γ—γ coin,I ce,cc,E β deduced logft,90Sr levels, mass separated90Rb. 相似文献
98.
The 13C chemical shifts and one-bond carbon-hydrogen coupling constants have been obtained for some hydroxycoumarins and their corresponding acetoxy and methoxy derivatives. The changes in the one-bond carbon-hydrogen coupling constants resulting from the conversion of a hydroxy group to an acetoxy group represent a simple method of assignment of the 13C NMR signals in coumarins which contain one or more hydroxy groups in the benzenoid ring. 相似文献
99.
Manas Banerjee Sankar Prasad Bhattacharyya 《International journal of quantum chemistry》1982,22(4):775-782
The considerations of Walsh rules are extended to rationalize the loss of planarity in the 1,3nπ* states of simple carbonyl and thiocarbonyl molecules. The role of Fermi correlation in shaping the differences between conformations in the singlet and the triplet state is emphasized. The role played by the π* orbital is also considered. 相似文献
100.