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141.
N. Bhattacharya B. Bapat S.A. Rangwala S.V.K. Kumar E. Krishnakumar 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,2(2):125-129
Lifetime measurements have been carried out for some low lying (n
= 2) levels in the four-electron ions Cl XIV and S XIII using the beam-foil technique. Accurate oscillator strengths for the
2
s2
1
S
- 2
s
2
p
1
P
o transition have been determined by the inclusion of prominent cascades in the analysis. Lifetimes of the levels of the 2
p2
3
P
j multiplet have also been measured for both ions. The results are compared with theoretical predictions and earlier measurements.
Received: 29 October 1997 / Revised: 10 February 1998 / Accepted: 5 March 1998 相似文献
142.
R. Bhattacharya 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(1):1-3
On the basis of a unique set of one body potentials and a good interpolation formula we have calculated orbit radii of valence nucleons of different nuclei near the closed shells ranging from calcium to bismuth and have found good agreement with the experimental results, thus demanding its use as a global one. 相似文献
143.
Gautam Bhattacharya 《Letters in Mathematical Physics》1980,4(5):361-366
An explicit form of a colour-singlet Fermion field is constructed from the operator solution of SU(n) Thirring model where the quark-fields are known to be confined in LSZ sense. In simple cases of massless quarks these ferions are free with zero mass and can be expressed as the antisymmetric composites of constituent quark fields. This simple exercise suggests an alternative to conventional two-dimensional QCD which seems to confine all Fermion including baryons by Schwinger mechanism. 相似文献
144.
145.
The sensitized Schiff's reagent has been used as an indicator in the neutralization of strong acids by means of strong or weak bases. (1) Since the acid to alkali transition is much sharper than the reverse process, the titration is best done by adding alkali to the acid. (2) The results are compared with those of titrations using methyl orange as indicator. (3) The end-point is very sharp with sensitized Schiff's reagent, the transition taking place from a dull red colour to an abrupt rise in intensity. (4) Acids which are comparable in strengths or weaker than H2SO3 cannot be titrated with this reagent as indicator. 相似文献
146.
D. P. Bhattacharya 《Czechoslovak Journal of Physics》1982,32(6):700-704
Faraday rotation characteristics due to non-equilibrium electrons in a covalent semiconductor are obtained under the condition when the cascade capture of the carriers is effective. It is shown that the results obtained here are useful for estimating some capture parameters. 相似文献
147.
148.
Pratul Bandyopadhyay Brahmananda Bhattacharya Harish Sarkar 《International Journal of Theoretical Physics》1983,22(8):677-689
In quantum neutrinodynamics (photon-neutrino weak coupling) all the renormalization constants vanish and therefore the field equations cannot be expressed in terms of unrenormalized field quantities. This helps us to formulate quantum neutrinodynamics as a convergent quantum field theory. It is also pointed out that from the viewpoint of the unified model of weak and electromagnetic interaction as developed on the basis of the photon-neutrino weak coupling by Bandyopadhyay, quantum electrodynamics also manifests itself as a convergent field theory. 相似文献
149.
150.
Tapas?GhoshEmail author Aparesh?Roy Sharmila?Bhattacharya Subhabrata?Banerjee 《Transition Metal Chemistry》2005,30(4):419-425
In the title family the tridentate ONO donor ligands are the fully deprotonated forms of acetylhydrazones of 2-hydroxybenzaldehyde (H2L1) and 2-hydroxyacetophenone (H2L2) (general abbreviation H2L), while bidentate mononegative OO donor ligands are the deprotonated salicylaldehyde (Hsal), vanillin (Hvan) and monodeprotonated 1,2-ethanediol (H2ed) (general abbreviation HB). The reaction of VIVO(acac)2 with H2L and Hsal or Hvan in equimolar ratio in MeOH afforded the complexes of the type [VVO(L)(B)], (1)–(4). The reaction of VIVO(acac)2 with H2L1 (in an equimolar ratio) and an excess of H2ed in MeOH yielded the complex [VVO(L1)(Hed)], (5) but the similar reaction with H2L2 ligand failed to produce such a type of complex. Complexes have been characterized by elemental analyses and by i.r., n.m.r. and u.v.-vis. spectroscopies. All the complexes are diamagnetic and display only LMCT bands. 1H-n.m.r. spectral data indicate that complexes (1)–(4) exist in two isomeric forms [(1A), (1B); (2A), (2B); (3A), (3B) and (4A), (4B)] in different ratios in CDCI3 solution. Complexes (1)–(4) display a quasi-reversible one electron reduction peak in the −0.06 to +0.05 V versuss.c.e. region in CH2CI2 solution and (5) displays an irreversible reduction peak at −0.46 V versuss.c.e. in DMF solution. The trend in the redox potential values has been correlated with the basicity of both the primary and auxiliary ligands. 相似文献