| 1. |
- Meng, Zhou, et al.
(författare)
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Observation of the lower hybrid waves near the three-dimensional null pair
- 2009
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Ingår i: Science in China Series G. - : Science Press. - 1672-1799 .- 1862-2844. ; 52:4, s. 626-630
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Tidskriftsartikel (refereegranskat)abstract
- Magnetic reconnection is a fundamental process in plasma, which is thought to play important roles both in laboratory and natural plasmas through affecting magnetic topology, heating and accelerating particles. During an event on Oct. 1st, 2001, the Cluster tetrahedron circled around the magnetic reconnection region several times, and Xiao et al. first identified the null pair and found that the spectrum of the null-point oscillation shows the maximum power near the lower-hybrid frequency. In this paper we report the observation of electromagnetic and electrostatic wave enhancements near lower hybrid frequency associated with the reconnection process near the null pair. The lower hybrid waves (LHWs) with quasi-perpendicular propagation were identified and also confirmed by the power law of the spectrum of electric and magnetic fields.
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| 2. |
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| 3. |
- Wang, C. K., et al.
(författare)
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First-principle studies of I-V properties of a molecular wire
- 2003
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Ingår i: Science in China Series G. - : Science China Press., Co. Ltd.. - 1672-1799 .- 1862-2844. ; 46:2, s. 113-121
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Tidskriftsartikel (refereegranskat)abstract
- The elastic scattering Green function method has been developed to describe the IN characteristics of molecular wires. The molecular electronic structure and the interaction between the molecule and the gold surface are two key factors for the charge transport properties of molecular wires in the formulas. An ab initio calculation at the hybrid density functional theory level is carried out to obtain the electronic structure of 4-4'-dimercaptodibenzene molecule. The frontier orbit theory and the perturbation theory are employed to determine the constant of the interaction energy between molecule and surface quantitatively. The numerical results show that the bonding between the sulfur atom and the gold atoms corresponds mainly to the covalent bond. Some molecular orbits are extended over molecule and gold cluster that certainly give channels for the charge transport, other molecular orbits are localized and the charge transport can take place by tunnel mechanism. At zero bias region, there exists a current gap. With the increasing bias, the conductance of the wire takes a shape of plateaus.
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| 4. |
- Zhovtobriukh, Iurii, et al.
(författare)
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Liquid Water Structure from X-ray Absorption and Emission, NMR Shielding and X-ray Diffraction
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Ingår i: Science in China Series G. - 1672-1799 .- 1862-2844.
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Tidskriftsartikel (refereegranskat)abstract
- Here we investigate to what extent X-ray absorption (XAS) and emission (XES) spectroscopy, the oxygen-oxygen radial distribution function and σ( 1H) and σ( 17O) NMR shielding can be represented by a common set of model structures of liquid water. This is done by using a Monte Carlo-based fitting technique which fits the spectra based on a library of ~1400 pre-computed spectra and assigns weights to contributions from different model structures. These are then used to re-weight the contributions from the structures in the library to reveal classes of structures that are over- or under-represented in the library. The goal is to include different experimental data sets which are sensitive to different aspects of liquid water structure and thus narrow down which types of structures must exist in the real liquid.
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