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91.
Arvind Nautiyal K. C. Sekhar N. P. Pathak Navneet Dabra Jasbir S. Hundal R. Nath 《Applied Physics A: Materials Science & Processing》2010,99(4):941-946
The ferroelectric and switching properties of spray deposited cesium nitrate: poly (vinyl alcohol) composite films at different
substrate temperatures (T
s
) have been studied. The optimum value of remanent polarization was obtained in the film deposited at T
s
=200°C, which may be due to larger structural distortion (c/a ratio) and less porosity as revealed by x-ray diffraction and field emission scanning electron microscope (FESEM) analysis.
The switching current transients have been analyzed by nucleation limited switching model (NLS) with the Lorentzian distribution
function. This model gives excellent agreement with the experimental polarization current throughout the whole time range.
The switching parameters were determined in the composite films deposited at different T
s
and found to be optimum at T
s
=200°C. The effect of pulse amplitude on the domain switching properties has also been studied and analyzed. The peak value
of polarization current exhibits an exponential dependence on the external applied field. 相似文献
92.
Charged analogue of Whittaker’s interior solution is derived which possess constant gravitational mass density (ρ+3p). The solution joins smoothly to Nordstörm solution at the pressure free interface. The solution has increasing energy density away from the center which is unphysical however such model can very well represent the situations when density undergoes abrupt changes during the tug of war between the gravitational attraction and electrostatic repulsion. 相似文献
93.
The properties of the relativistic alpha fragments produced in interactions of 84Kr at around 1 A GeV in nuclear emulsion are investigated. The experimental results are compared with the similar results
obtained from various projectiles with emulsion interactions at different energies. The total, partial nuclear cross-sections
and production rates of alpha fragmentation channels in relativistic nucleus-nucleus collisions and their dependence on the
mass number and initial energy of the incident projectile nucleus are investigated. The yields of multiple alpha fragments
emitted from the interactions of projectile nuclei with the nuclei of light, medium and heavy target groups of emulsion-detector
are discussed and they indicate that the projectile-breakup mechanism seems to be free from the target mass number. It is
found that the multiplicity distributions of alpha fragments are well described by the Koba-Nielsen-Olesen (KNO) scaling presentation.
The mean multiplicities of the freshly produced or newly created charged secondary particles, normally known as shower and
secondary particles associated with target in the events where the emission of alpha fragments were accompanied by heavy projectile
fragments having Z ≥ 3 seem to be constant as the alpha fragments multiplicity increases, and exhibit a behavior independent of the alpha fragments
multiplicity. 相似文献
94.
Shinoo Srivastava Seema Srivastava M. K. Pandey S. K. Naman Shweta Srivastava 《Journal of Macromolecular Science: Physics》2013,52(3):617-636
A study of the normal modes of vibration and their dispersion in polyadenylic acid based on the Urey–Bradley force field is reported. It gives a better interpretation of FTIR spectra as compared with the valence force field. Characteristic features of dispersion curves such as regions of high density‐of‐states, repulsion, and character mixing of dispersive modes are discussed. Predictive valuzes of heat capacity as a function of temperature are reported. 相似文献
95.
Chitra Shukla Anindita Banerjee Anirban Pathak 《International Journal of Theoretical Physics》2013,52(6):1914-1924
Recently, Hwang et al. (Eur. Phys. J. D 61:785, 2011) and Yuan et al. (Int. J. Theor. Phys. 50:2403, 2011) have proposed two efficient protocols of secure quantum communication using 3-qubit and 4-qubit symmetric W state respectively. These two dense coding based protocols are generalized and their efficiencies are considerably improved. Simple bounds on the qubit efficiency of deterministic secure quantum communication (DSQC) and quantum secure direct communication (QSDC) protocols are obtained and it is shown that dense coding is not essential for designing of maximally efficient DSQC and QSDC protocols. This fact is used to design maximally efficient protocols of DSQC and QSDC using 3-qubit and 4-qubit W states. 相似文献
96.
Chitra Shukla Anindita Banerjee Anirban Pathak 《International Journal of Theoretical Physics》2013,52(10):3790-3796
Recently bidirectional controlled perfect teleportation using 5-qubit states are reported in Int. J. Theor. Phys. (2013), doi:10.1007/s10773-013-1484-8 and ibid (2012), doi:10.1007/s10773-012-1208-5. In this paper we have shown that there exists a class of 5-qubit quantum states that can be used for bidirectional controlled teleportation. Two out of the three reported cases are the special cases of the proposed class of 5-qubit quantum states and one of them is not strictly a case of controlled bidirectional quantum teleportation. Further, we have shown that one can in principle, construct infinitely many 5-qubit quantum states for this purpose. We have also shown that the idea can be extended to bidirectional controlled probabilistic teleportation. Some potential applications of the proposed scheme and its modified versions are also discussed in relation with the implementation of quantum remote control and quantum cryptography. 相似文献
97.
Shweta Srivastava Shinoo Srivastava Seema Srivastava Vishwambhar Dayal Gupta Sanjeev John La'Verne 《Journal of Macromolecular Science: Physics》2013,52(1):157-173
A study of the normal modes of vibration and their dispersion in polypyrrole (PPY) based on the Urey-Bradley force field is reported. It gives a fuller interpretation of previously reported FTIR spectra. Characterstic features of dispersion curves, such as regions of high density-of-states, repulsion, and character mixing of dispersive modes, are discussed. Predictive values of heat capacity as a function of temperature are reported. 相似文献
98.
Using Hankel transform the symbol 'a' is defined and the pseudo-differential operator (p.d.o.) hμ,a associated with the Bessel operator d 2/dx 2 + (1 ? 4μ 2)/4x 2 in terms of this symbol is defined. It is shown that the operator hμ,a is a continuous linear map of a Hankel invariant space into itself. A special pseudo-differential operator called the Hankel potential is defined and some of its properties are investigated. 相似文献
99.
Ram Shankar Pathak 《Applicable analysis》2013,92(10):1223-1236
A class of pseudo-differential operators (p.d.o.'s) associated with the general Fourier kernel studied by Hardy and Titchmarsh is defined. A symbol class T m is introduced. It is shown that the p.d.o.'s associated with the symbol are continuous linear mappings of the Braaksma and Schuitman space T(λ,μ) into itself. An integral representation of p.d.o. is obtained. Some special forms of the symbol are considered. It is shown that these p.d.o.'s and their products are bounded in certain Sobolev type space. 相似文献
100.