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51.
R.P. Singh R.K. Bhowmik S.S. Ghugre S.B. Patel 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):35-40
High spins states in 99Rh were populated via the 66Zn(37Cl, 2p2n)99Rh reaction at an incident beam energy of 130 MeV. Seventeen new transitions have been observed in the present study and the
level scheme has now been extended up to a spin of J∼ 25ħ and an excitation energy of about E
x∼ 10 MeV. The observation of a positive parity E2 cascade based on the 9/2+ isomeric level is suggestive of collective behaviour in this nucleus up to high spins. Spherical shell model (within restricted
model space) and Cranked shell model calculations were performed to obtain an insight into the observed level structure. The
new collective band observed up to a spin of J∼ 25ħ is suggested to be based on (πg
9/2
3) ⊗ (νg
7/2
2) quasi-particle excitations.
Received: 12 July 1999 / Revised version: 14 September 1999 相似文献
52.
We report a correlation between structural phase stability and magnetic properties of Co2FeO4 spinel oxide. We employed mechanical alloying and subsequent annealing to obtain the desired samples. The particle size of the samples changes from 25 nm to 45 nm. The structural phase separation of samples, except sample annealed at 900 °C, into Co-rich and Fe-rich spinel phase has been examined from XRD spectrum, SEM picture, along with EDX spectrum, and magnetic measurements. The present study indicated the ferrimagnetic character of Co2FeO4, irrespective of structural phase stability. The observation of mixed ferrimagnetic phases, associated with two Curie temperatures at TC1 and TC2 (>TC1), respectively, provides the additional support of the splitting of single cubic spinel phase in Co2FeO4 spinel oxide. 相似文献
53.
The alpha-decay of states in 18O have been studied in the inelastic scattering reaction at 82 MeV. The double differential cross sections have been analysed with a strong absorption model. A systematic dependence of emission angle on spin is observed, allowing the determination of the transferred angular momentum. 相似文献
54.
Pradip K. Bhowmik Gregory Beaucage Subrata K. Bhattacharya Robert W. Lenz 《Journal of Polymer Science.Polymer Physics》1994,32(6):1023-1031
The degree of crystallinity of as-made fully aromatic, thermotropic polyesters was determined for two different series of polymers, each of which contained a symmetric monomer having either pendant phenyl groups or fused aromatic rings by the WAXD technique. All of the homopolymers had a high degree of crystallinity in spite of bulky substituents attached to the mesogenic moiety. Surprisingly, the homopolymer of 2,6-naphthalenedicarboxylic acid with each of the monomers had a higher degree of crystallinity and Tm than those of the homopolymer of terephthalic acid with each of the respective monomers. As expected, on copolymerization with 30 mol % of either 4-hydroxybenzoic acid or 6-hydroxy-2-naphthoic acid, all of the resulting copolymers had a much lower degree of crystallinity and Tm/Tf values compared to those of the respective homopolymers in each series. © 1994 John Wiley & Sons, Inc. 相似文献
55.
G. Gangopadhyay Samit Bhowal R. K. Bhowmik U. Datta Pramanik P. Ghosh A. Goswami C. Petrache A. Mukherjee S. Muralithar Rajarshi Raut M. Saha Sarkar A. K. Singh R. P. Singh S. Bhattacharya 《The European Physical Journal A - Hadrons and Nuclei》2005,24(2):173-178
The band structures of the doubly odd 138Pr nucleus have been investigated using the 128Te(14N, 4n)138Pr reaction at a beam energy of 55-65 MeV. Altogether six distinct structures have been established, of which the lower part of the yrast band and two side bands were known from earlier works. The observed level properties of the members of the yrast band have been compared with theoretical calculations performed within the Particle Rotor Model (PRM) with axially symmetric core. The experimental branching ratios and B(M1)/B(E2) values when compared with the theoretical results of the PRM, suggest an oblate core. 相似文献
56.
K. C. Anand R. R. Daniel F.A.Sc. S. A. Stephens B. Bhowmik C. S. Krishna P. K. Aditya R. K. Puri 《Proceedings Mathematical Sciences》1968,67(3):138-154
An experiment has been carried out using an oriented stack of nuclear emulsions to determine the rigidity spectrum of cosmic ray helium nuclei between 12 and 40 GV, by taking advantage of the variation of the geomagnetic cut-off rigidity in the east-west plane over Hyderabad, India. Altotal of 2433 identified helium nuclei recorded in the stack, has been divided into 8 angular intervals in the east-west plane corresponding to 8 different cut-off rigidities. From this the integral fluxes of helium nuclei at the top of the atmosphere have been obtained for all the 8 rigidity intervals. The vertical flux above an effective threshold rigidity of 16·73 GV has been determined with high statistical accuracy and has a value of 15·0±0·5 helium nuclei (m2.sr.sec.)?1. The rigidity spectrum of these nuclei between 12 and 40 GV can be well represented by a power law of the type N (>R) =1990 R?1.74±0.11 (m2.sr.sec.)?1 and is the first direct determination so far made in this rigidity region. The differential rigidity spectra of protons, helium nuclei and S-nuclei of the cosmic radiation in the vicinity of the earth at solar minimum (1965) have been constructed with the existing world data and it is found that for rigidities ? 10 GV, the three spectra have, within experimental errors, the same slope of 2·6. The ratio P/He and He/S of the differential fluxes have been studied as a function of rigidity. It is found that for R>2 GV, the ratio P/He has, within experimental errors, a constant value of 6·3; as for the ratio He/S, it seems that the experimental data above a GV is not inconsistent with a constant value of 14 over the entire rigidity interval considered here. 相似文献
57.
Detailed measurement of spectral broadening in a poly-[2, 4 hexadiyne-1, 6 diol-bis-(p -toluene sulfonate)] (PTS) single crystal owing to self-phase modulation was performed as a function of wavelength by use of a Ti:sapphire laser producing 200-fs pulses at 720-920 nm and a Nd:YAG laser producing 50-ps pulses at 1064 nm. The nonlinear refractive index (n(2)) of PTS at these wavelengths was determined from the measured phase shift. Group-velocity dispersion was estimated and found to have a negligible effect on the observed spectral broadening. The two-photon absorption coefficient (alpha(2)) over this wavelength range was determined from nonlinear transmission measurements. The largest magnitude of n(2) observed at 720 nm was 3.9x10(-5)cm (2)/MW . The results show that the magnitude of n(2) monotonically decreases as wavelength is increased away from resonance, and two-photon absorption does not make a significant contribution to n(2) at off-resonant wavelengths up to 1064 nm. 相似文献
58.
P. Thakur R. Dogra A. K. Bhati S. C. Bedi R. P. Singh S. Muralithar R. K. Bhowmik 《Hyperfine Interactions》2000,131(1-4):103-109
The electric quadrupole moments of the 9/2− and 21/2− isomeric states of 173Ta at 165.8 keV and 1713.2 keV, respectively, were measured as Q(9/2−)=2.92(15) b and Q(21/2−)=6.23(18) b for the first time using the TDPAD technique. A 66 MeV pulsed 12C ion beam from the 15UD pelletron accelerator facility of the Nuclear Science Centre at New Delhi was used in the reaction
165Ho(12C, 4nγ)173Ta. The experimental values of equilibrium deformations β2(9/2−)=0.251(7) and β2(21/2−)=0.391(7) were extracted.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
59.
60.
Alexi K. Nedeltchev Haesook Han Pradip K. Bhowmik Longzhou Ma 《Journal of polymer science. Part A, Polymer chemistry》2011,49(8):1907-1918
Several new poly(pyridinium salt)s with quinoline diamine moieties in their backbones with tosylate and triflimide counterion were prepared by either a ring‐transmutation polymerization reaction with bis(pyrylium tosylate) with a series of isomeric quinoline diamines in dimethyl sulfoxide (DMSO) for 48 h at 130–140 °C or a metathesis reaction of the tosylate polymers with lithium triflimide in DMSO at about 60 °C. Their chemical structures were confirmed by FTIR, 1H and 13C NMR spectroscopy, and elemental analysis. Their number‐average molecular weights (Mn) were in the range of 18,000–58,000, and their polydispersities were in the range of 1.12–1.53 as determined by gel permeation chromatography. They had thermal stability in the temperature range of 353–455 °C and glass‐transition temperatures >240 °C. They had good solubility in common organic solvents and were characterized with polarizing optical microscopy (POM) studies for their lyotropic liquid‐crystalline properties. Their light‐emission properties were examined by spectrofluorometry in both the solution and film states. Their quantum yields were also determined. Additionally, their morphologies in the thin‐film states and melt‐drawn fibers were examined with POM, scanning electron microscopy, and transmission electron microscopy techniques. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献