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991.
992.
International Journal of Theoretical Physics - In 2016, Li et al. [Int. J. Theor. Phys. 55, 1820–1823 (2016)] proposed schemes for quantum teleportation of certain class of three and four...  相似文献   
993.
The European Physical Journal E - The buckling and twisting of slender, elastic fibers is a deep and well-studied field. A slender elastic rod that is twisted with respect to a fixed end will...  相似文献   
994.
H S Yadav  V P Singh 《Pramana》1982,18(4):331-338
Study of propagation of a spherically converging shock wave has been carried out by Whitham’s method. The variation of shock velocity and pressure along the radius of curvature has been calculated numerically for a number of metals. Attempt has also been made to compare the experimental results of velocity of detonation wave with those reported elsewhere by the application of Whitham’s method. A good agreement between experimental and theoretical results has been obtained in this study.  相似文献   
995.
The total (p, n) reaction cross section for48Ca has been measured as a function of proton energy in the energy range 1.885 to 5.100 MeV with an overall resolution of ∼ 2 keV and in ∼ 5 keV energy steps. The fluctutions in fine resolution data have been analysed to determine the average coherence width 〈Γ〉. The excitation function averaged over large energy intervals has been analyzed in terms of the optical model. The isobaric analogue resonances atE p ∼ 1.95 and 4 MeV have been shape-analyzed to extract the proton partial width and the spectroscopic factorS n . A comparison of the gross structures observed in ∼ 55 keV averaged excitation function with the predictions of Izumo’s partial equilibrium model has also been made.  相似文献   
996.
V K Singh  R Chandra  S Lokanathan 《Pramana》1982,18(3):243-248
A Mössbauer study of systems Co x Mn3?x?y Fe y O4 and Ni x Mn3?x?y Fe y O4 for values ofx=0·1, 0·5, 1·0 andy ranging from 0·1 to 2·0 in steps of 0·2 have been made. At room temperature samples fory values ranging in between 0·1 to 0·5 exhibit paramagnetic behaviour while all spectra for values ofy between 0·6 to 0·8 show relaxation effects. Well-defined hyperfine Zeeman spectra are observed for all the samples withy>0·8 and resolved in two sextets corresponding to octahedral and tetrahedral site symmetries and a central doublet probably due to the presence of super-paramagnetic particles in the system. The hyperfine field at57Fe nucleus reduces with decreasing iron cobalt and nickel concentration. These observations have been explained in terms of site preference of cations and exchange interactions.  相似文献   
997.
B A Mattoo  Y Singh 《Pramana》1982,19(5):483-496
Using a generalized two-fluid pictures for the charge of superconductor and ordinary Boltzmann equation for quasiparticle excitations, the effect of frequency and wave-vector dependent electromagnetic perturbation on charge imbalance near transition temperatureT C is studied. In a situatiod where both the effective charge and distribution function of quasiparticles deviate from their equilibrium values, the charge imbalance is shown to possess a propagating solution at frequencies greater than inelastic scattering rate. In situations where charge imbalance is created by injection of quasiparticles, the charge imbalance relaxation rate is shown to decrease. We also study the effect of applied perturbation on quasiparticle diffusion length and hence on superconductor—normal interface boundary resistance.  相似文献   
998.
We discuss the critical behaviour of an ideal relativistic Bose gas (in d dimensions) with a net charge including the effects of pair production. We show that the critical exponents of the system are the same as those of the usual nonrelativistic Bose gas. The universal ratios formed from the critical amplitude are also the same as those of the usual Bose gas.  相似文献   
999.
Measurements were carried out to deduce the transverse kinetic energies of highly charged argon recoil ions produced in single collisions of 120 MeV ions with argon atoms in which the post collision charge states of the projectiles were not determined. A time of flight spectrometer was designed and fabricated to detect the charge states of recoils. Experimental procedures for optimizing the spectrometer for extraction, transmission and detection of recoils are described. A simple approach for determining the transverse kinetic energy of the recoil ions from FWHM of the peaks is reported. This method is shown to be independent of the choice of collision partners and requires only the knowledge of the physical values of “optimized parameters” of time-of-flight spectrometer used in the experiment. The transverse kinetic energy of the recoil ions determined from the present approach is found to vary from 0.03 eV for to 4.02 eV for Ar10+. These values are compared with the results reported by earlier workers and are shown to follow a q2-behaviour up to a charge state q =8+ of the recoil ions. Received: 5 February 1998 / Revised: 8 June 1998 / Accepted: 11 June 1998  相似文献   
1000.
2 SO4. The solid solubility limits up to x≤3 mole% for monovalent, x≤5.27 mole% for divalent and x≤3.63 mole% for trivalent cation doped Ag2SO4 are set with XRD, SEM, IR and DSC techniques. A predominant dependence of conductivity on the ionic size of iso- and alio-valent cations is observed. In particular, the conductivity enhances in both α and β phases, despite having a lower ionic-size dopant cation (relative to that of Ag+) in the transition element cation doped Ag2SO4. Ca2+, Ba2+, Y3+ and Dy3+ doped samples show depature from the regular behaviour in the β-phase. The conductivity behaviour is discussed considering ionic size, valence and electronic structure of the guest cations. Received: 3 February 1997/Accepted: 27 May 1997  相似文献   
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