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91.
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Memristors as fundamental two-terminal electric circuit elements can be miniaturised to extreme extents. However like other electronic devices memristors can have application in the field of electrical engineering as well, e.g. in the fields of over-current protection, over-voltage protection and EMC. This paper proposes an application opportunity of memristors in ESD protection. Based on their purely dissipative character, these devices can usefully co-operate with ceramic capacitors having no ability to dissipate the energy of ESD surges. A type of structure of memristors for ESD protection purposes and a SPICE model are proposed.  相似文献   
94.
The dispersion of the Cu-O bond-stretching and bond-bending vibrations in YBa(2)Cu(3)O(6.6) has been studied by high resolution inelastic neutron scattering. While the behavior of the bond-bending vibrations can be well accounted for by a simple potential model, the bond-stretching vibrations show a highly anomalous behavior. The displacement pattern of the most anomalous phonons is in principle consistent with dynamic charge stripe formation. However, charge stripes would have to extend along the a axis and not the b axis as inferred from the magnetic fluctuations by Mook et al. [Nature (London) 404, 729 (2000)].  相似文献   
95.
Results on the multiplicity structure of diffractively excited meson and proton systems in À+/K+ p interactions at 250 GeV/c are presented for diffractive masses up to about 9 GeV. The energy dependence of the average charge multiplicity and the shape of the multiplicity distribution in terms of KNO-scaling and negative binomial distribution are investigated. The diffractive systems are compared toe + e ,lh and non-diffractivehh final states as suggested by modern approaches of the Pomeron-hadron collision. Systematic differences are found between diffractive meson and proton systems but also between diffraction and the reactions compared to.  相似文献   
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A basis of Hermite splines is used in conjunction with the collocation method to solve the orbital equations for diatomic molecules. Accurate solutions of the Hartree-Fock equations are obtained using iterative methods over most regions of space, while solving the equations by Gaussian elimination near the nuclear centres. In order to improve the speed and accuracy of our iterative scheme, a new self-adjoint form of the Hartree-Fock equation is derived. Using this new equation, our iterative subroutines solve the Hartree-Fock equations to one part in 106. The Gaussian elimination routines are accurate to better than one part in 108.  相似文献   
99.
Beker  H.  Bøggild  H.  Boissevain  J.  Cherney  M.  Dodd  J.  Esumi  S.  Fabjan  C. W.  Fields  D. E.  Franz  A.  Hansen  K. H.  Holzer  B.  Humanic  T.  Jacak  B.  Jayanti  R.  Kalechofsky  H.  Kobayashi  T.  Kvatadze  R.  Lee  Y. Y.  Leltchouk  M.  Lörstad  B.  Maeda  N.  Medvedev  A.  Miake  Y.  Miyabayashi  A.  Murray  M.  Nagamiya  S.  Nishimura  S.  Noteboom  E.  Pandey  S. U.  Piuz  F.  Polychronakos  V.  Potekhin  M.  Poulard  G.  Sakaguchi  A.  Sarabura  M.  Shigaki  K.  Simon-Gillo  J.  Sletten  H.  Sondheim  W.  Sugitate  T.  Sullivan  J. P.  Sumi  Y.  van Hecke  H.  Willis  W. J.  Wolf  K. 《Zeitschrift fur Physik C Particles and Fields》1994,64(2):209-217
K+K+ and KK correlations from S+Pb collisions at 200 GeV/c per nucleon and K+K+ correlations from p+Pb collisions at 450 GeV/c per nucleon, are presented as measured by the focusing spectrometer of the NA44 experiment at CERN. Multidimensional fits are performed in order to characterize the kaon-emission volume, which is found to be smaller than the pion-emission volume.  相似文献   
100.
Differential cross-sections for the reactions d (γ,π0)d and d (γ,π0)pn have been measured at MAMI with the TAPS detector setup in the energy range 140 MeV < E γ < 306 MeV. By use of the Glasgow tagging spectrometer an 0.8 MeV energy resolution for photons incident on the target was achieved. The π0 missing energy resolution was sufficient for a reliable separation of coherent and incoherent channels. The data for the break-up channel exhibit very strong final state interaction effects, whereas the observed angular dependence of the inclusive process d (γ,π0)X is in quantitative agreement with predictions for a quasi-free process. The observed absolute d (γ,π0)X cross-sections, on the other hand, are significantly smaller than predicted by the quasi-free process for E γ >∼ 250 MeV. Associating this failure with the π0 photoproduction on the neutron would suggest that its cross-section is up to 25% below the presently believed value. Received: 13 February 2001 / Accepted: 13 April 2001  相似文献   
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