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By
Rahman, A; Mahanta, P C
The size effect on electrical conduction is observed in bismuth films in the region of film thickness above 2000 Å. Applying FuchsSondheimer theory and assuming specularity parameterp = 0·8, the value of bulk resistivity and mean free path are obtained as 6·692 × 10^{4} ohmcm and 6000 Å respectively.
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By
Naik, Pratibha; Rao, N Rajeswara
3 Citations
Infrared intensity analysis of MXY_{2} type molecules has been attempted. The dipole momentμ of C=O is obtained to be different for different moleculesviz. for CH_{2}O, 1.9052; for COCl_{2}, 1.1517; for COF_{2}, 0.6340; and for COBr_{2}, 0.7687. Similarly in the case of CSF_{2} and CSCl_{2}μ_{C=S} it was found to be 0.2473 and 0.2983 respectively. This shows that the effect of the electronegative halogen atoms is very important.
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By
Rajaraman, R
3 Citations
We critically examine some recent claims that certain field theories with and without boson kinetic energy terms are equivalent. We point out that the crucial element in these claims is the finiteness or otherwise of the boson wavefunction renormalisation constant. We show that when this constant is finite, the equivalence proof offered in the literature fails in a direct way. When the constant is divergent, the claimed equivalence is only a consequence of improper use of divergent quantities.
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By
Mookerjee, Abhijit
15 Citations
Starting from a physical RKKY interaction model for magnetic alloys and a valid probabilistic description of a random substitutional alloy, the possible phases have been studied in a mean field, effective medium theory. Most of the detailed objections raised against former treatments of these systems have been removed.
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By
Potbhare, V
1 Citations
MonteCarlo calculations inds shell space have been done using twobody random interactions, to obtain ensembleaveragemparticle scalar moments up to fourth order. A shift of the spectrum shape from semicircle to Gaussian with respect to the increase in number of particles can be clearly seen in terms of the ensembleaveraged fourth moment.
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By
Chaddah, P
2 Citations
A scheme to calculate the electron momentum density in simple liquid metals, with the effect ofboth electron correlations and ionic potentials included, is given. This scheme is applied to the case of liquid aluminium. The results are substantially different from calculations considering only the ion potentials, and also from the results for a homogeneous electron gas of corresponding density.
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By
Deshmukh, S V
The effect of Gaunt factor correction on temperature estimation over a range 100 to 1500 eV had been studied. Greene’s analytical expression for the quantum mechanical Gaunt factor averaged over Maxwellian distribution is used. Transmission ratios are calculated with and without Gaunt factor for various combinations of beryllium foils, taking into account xray emission due to freefree transitions. A significant difference (≳ 15%) is observed between the temperatures estimated from classical and quantum mechanical curves, above 600 eV. Selection of foil combinations useful for estimating higher temperatures is also discussed.
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By
Ahalpara, D P; Bhatt, K H
The separation betweenT=0 andT=1 centroids of the empirical effective interaction is fairly large for the (d_{3}^{2/−1}f_{7/2})JT particlehole interaction as compared to nearby (f_{7/2})^{2}JT and (d_{5/2})^{2}JT particleparticle interactions. This interesting feature of the empirical effective interaction is shown to arise as a consequence of renormalization of the effective interaction as one truncates the configuration space from (s−d)^{−1}(f−p)^{1} to (d_{3}^{2/−1}f_{7/2}) and from (f−p)^{2} and (s−d)^{2} configurations to (f_{7/2})^{2} and (d_{5/2})^{2} respectively.
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By
Mehta, C L; Kumar, Sunil
2 Citations
We consider the states with extremum products and sums of the uncertainties in noncommuting observables. These are illustrated by two specific examples of harmonic oscillator and the angular momentum states. It shows that the coherent states of the harmonic oscillator are characterized by the minimum uncertainty sum 〈(Δq)^{2}〉 + 〈(Δp)^{2}〉. The extremum values of the sums and products of the uncertainties of the components of the angular momentum are also obtained.
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