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101.
J. P. B. Silva K. C. Sekhar A. Almeida J. Agostinho Moreira M. Pereira M. J. M. Gomes 《Applied Physics A: Materials Science & Processing》2013,113(2):379-384
BaTiO3 thin films were deposited by pulsed laser deposition on Pt–Si at different laser pulse repetition frequencies. X-ray diffraction spectra show that preferred oriented films can be grown by adjusting the pulse repetition frequency. Enhanced dielectric and ferroelectric properties obtained in films deposited at 1 Hz is attributed to preferred orientation, low strain and homogeneous grain distribution. The films deposited at 1 Hz show an impressive remanent polarization of 21.4 μC/cm2 with a coercive field of 70.0 kV/cm. The shift in Curie temperature, which stems from changing the laser pulse repetition frequency, is associated with the strain state in the film. 相似文献
102.
103.
The translation of a sphere moving along the axis of a rotating viscous fluid is studied by the finite difference method at moderate Reynolds (up to R = 500) and Taylor (up to T = 100) numbers. Suppression of the separation is observed with increasing rotation parameter T. The drag coefficient is also presented. It is observed that the drag coefficient is less than that with no rotation in the range 0<N<0·7, where N = 2T/R is the inverse Rossby number. The same phenomenon was observed experimentally by Maxworthy in the range 0<N<0·75±0·03. 相似文献
104.
C.P. Bust J.R. Carter W.W. Neale J.G. Rushbrooke D.R. Ward R.E. Ansorge B.Y. Oh M. Pratap G. Sionakides G.A. Smith J. Whitmore R. Raja L. Voyvodic 《Nuclear Physics B》1978,140(3):409-422
We have investigated the reactions . The final state is dominated by diffractive production of a system which shows a strong tendency to form . The process is also observed in this reaction, indicating an energy dependence of s?1.5±0.1. The channel shows less single diffraction, and has a doubly diffractive component consistent with pomeron factorization. Strong Δ++(Δ++) production is agoain seen, but in contrast to the channel we also observe considerable ?0 production. 相似文献
105.
R.E. Ansorge J.R. Carter R.P. Mount W.W. Neale R. Raja J.G. Rushbrooke 《Nuclear Physics B》1975,97(3):439-444
We present data on the inclusive neutron spectra produced in the forward direction by the interactions of 23.85 GeV/c protons in a copper target. The results are in good agreement with the predictions of the triple-Regge model. 相似文献
106.
M. Yasin Akhtar Raja Wade N. Sisk Mohammad Yousaf David Allen 《Applied physics. B, Lasers and optics》1996,64(1):79-84
Experimental investigations of the photon’s B
(3)-field (third longitudinal polarization) are reported. The existence of an “axial magnetostatic field of photon” has been
predicted in B
π or B
(3)-theory as the fundamental property of the circularly polarized light, and reported in numerous papers and monographs. High-sensitivity
detection has been employed in photomagnetic induction, Faraday, and inverse Faraday effects (IFE) originating from such a
field. The results of all three experiments clearly disprove the claims of B
π-theory. Putting together these results and theoretical calculations in perspective, it is concluded that such fields are
non-existent.
Received: 25 January 1996 / Revised version: 24 May 1996 相似文献
107.
Of the four anthracene sulphonates (Na-salt), anthracene-1-sulphonate (1-AS), anthracene-2-sulphonate (2-AS) and anthracene-1, 5-disulphonate (1, 5-AS) show temperature dependence of φf, whereas for anthracene-1, 8-disulphonate (1, 8-AS) φf is independent of temperature. Ea for 1-AS, 2-AS and 1, 5-AS are 939 cm?1, 1144 cm?1 and 445 cm?1, respectively. A low energy Tnπ1 level supplied by ?SO?3 group could be responsible for efficient ISC in 1, 8-AS of symmetry C2v. The possibility of tunnelling due to molecular distortion i.e. “geometry factor” cannot be ruled out also. 相似文献
108.
Raja R Golovko VB Thomas JM Berenguer-Murcia A Zhou W Xie S Johnson BF 《Chemical communications (Cambridge, England)》2005,(15):2026-2028
Nanoparticles of Co and NiPd, derived from colloidal precursors and supported on commercially available non-ordered mesoporous silica, are highly effective, cheap, recyclable and industrially viable catalysts for the hydrogenation of a range of nitro-substituted aromatics under mild conditions. 相似文献
109.
A. Varada Rajulu S. Raja Ratnam R. Ramakrishna Reddy 《Journal of Quantitative Spectroscopy & Radiative Transfer》1983,29(1):85-88
The force constants for diatomic molecules and isolated bonds may be expressed by using equalized electro-negativities, bond orders, bond strengths and interatomicdistances. We have studied Mn1H, Mn2H, Co2H, Ni1H, Ni2H, Cu1H, Cu2H, Ag1H, and Ag2H and have determined the proportionality constant d, as well as the Lennard-Jones parameters a and b, for the potential energy functions used by Szöke and calculated the anharmonicity ωeξe and the rotational-vibrational coupling constant αe. The relation between electronegativity and ionization potential has been verified and the variations of molecular parameters with atomic number Z have been studied. 相似文献
110.
Frequencies of free vibration of rectangular plates of arbitrary thickness, with different support conditions, are calculated by using the Method of Initial Functions (MIF), proposed by Vlasov. Sixth and fourth order MIF theories are used for the solution. Numerical results are presented for three square plates for three thickness ratios. The support conditions considered are (i) three sides simply supported and one side clamped, (ii) two opposite sides simply supported and the other two sides clamped and (iii) all sides clamped. It is found that the results produced by the MIF method are in fair agreement with those obtained by using other methods. The classical theory gives overestimates of the frequencies and the departures from the MIF results increase for higher modes and larger thickness ratios. 相似文献