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11.
Joydeep Choudhury Srinivasa Rao Karumuri Nirmal Kumar Sarkar Ramendu Bhattacharjee 《Pramana》2009,73(5):881-887
In this paper the stretching vibrational modes of CF4 isotopes are calculated up to first overtone using the one-dimensional vibron model for the first time. The model Hamiltonian
so constructed seems to describe the C-F stretching modes accurately using a relatively small set of well-defined parameters. 相似文献
12.
Jameson MaibamB. Indrajit Sharma Ramendu BhattacharjeeR.K. Thapa R.K. Brojen Singh 《Physica B: Condensed Matter》2011,406(21):4041-4045
We have studied the electronic, structural, and elastic properties of scandium carbide and yttrium carbide by means of accurate first principles total energy calculations using the full-potential linearized plane wave method (FP-LAPW). We have used the generalized gradient approximation (GGA) for the exchange and correlation potential. Volume optimization, energy band structure, and density of states (DOS) of the systems are presented. The second order elastic constants have been calculated and other related quantities such as the Zener anisotropy factor, Poisson's ratio, Young's modulus, Kleinman parameter, Debye temperature, and sound velocities have been determined. The band gap calculation shows that YC is relatively more ionic than ScC. 相似文献
13.
In this paper, we discuss an ordinary differential equation mathematical model for the spread of malaria in human and mosquito
population. We suppose the human population to act as a reservoir. Both the species follow a logistic population model. The
transmission coefficient or the interaction coefficient of humans is considered to be dependent on the mosquito population.
It is seen that as the factors governing the transmission coefficient of humans increase, so does the number of infected humans.
Further, it is observed that as the immigration constant increases, it leads to a rise in infected humans, giving an endemic
shape to the disease. 相似文献
14.
Copper nanoparticles have been prepared through the reduction of cupric ions by ethanol with linoleic acid as a capping agent.
The morphology and structure of these nanoparticles have been investigated using transmission electron microscopy. The X-diffraction
study shows that the nanoparticles are crystalline and mainly composed of face-centered cubic (fcc) copper with a narrow size
distribution having an average size of 5 nm. Fluorescence spectra of these copper nanoparticles have been analysed which show
two emission peak at 450 nm and 625 nm corresponding to the large energy band and small energy band respectively, when illuminated
at 250 nm of an optical source. 相似文献
15.
Srinivasa Rao Karumuri Nirmal Kumar Sarkar Joydeep Choudhury Ramendu Bhattacharjee 《Molecular physics》2013,111(14):1733-1737
An algebraic model of coupled anharmonic oscillators is introduced, capable of describing the stretching vibrations of medium and large polyatomic molecules. This model is applied to the calculation of Cm–H and C β –C β vibrational modes of nickel octaethyl porphyrins and nickel porphyrins molecules. The model appears to describe the data accurately. 相似文献
16.
Nirmal Kumar Sarkar Joydeep Choudhury Ramendu Bhattacharjee 《Molecular physics》2013,111(19):3051-3055
Using Lie algebra the vibrational energy levels of HCN were calculated using the local Hamiltonian for 35 vibrational bands. A comparative study was made with earlier results. 相似文献
17.
In this paper, we have obtained the solution of the unpolarized coupled Dokshitzer–Gribove–Lipatov–Alterelli–Parisi (DGLAP) evolution equation in leading order at the small-x limit. Here, we have used a Taylor series expansion, separation of functions and then the method of characteristics to solve the evolution equations. We have also calculated t-evolution of singlet and gluon distribution functions and the results are compared with E665 and NNPDF data for singlet structure function and GRV1998 and MRST2004 gluon parametrizations. It is shown that our results are in good agreement with the parametrizations especially at small-x and high-Q 2 region. From global parametrizations and our results, we have seen that the singlet and gluon distribution functions increase when Q 2 increases for fixed values of x. 相似文献
18.
Joydeep Choudhury Srinivasa Rao Karumuri Rupali Sinha Nirmal Kumar Sarkar Ramendu Bhattacharjee 《Indian Journal of Physics》2010,84(6):659-664
In this paper, we introduce one dimensional vibron model to analyze the fundamental, overtone and combination modes of CF4 molecule and both stretching, bending vibrational mode of bent H2O molecule up to first overtone with few algebraic parameters. Using the model Hamiltonian, we reported here better results
for the vibrational spectra of H2O. Our analysis suggests some reassignments of levels and predicts location of states in case of CF4 molecule which was not yet observed. 相似文献
19.
Srinivasa Rao Karumuri Joydeep Choudhury Nirmal Kumar Sarkar Ramendu Bhattacharjee 《Pramana》2009,72(3):517-525
One of the most interesting areas of current research in molecular physics is the study of the vibrationally excitated states
of medium and large molecules. In view of the considerable amount of experimental activity in this area, one needs theoretical
models within which to interpret experimental data. Using Lie algebraic method, the vibrational energy levels of nickel metalloporphyrins
like Ni(OEP), Ni porphyrin and Ni(TPP) are calculated for 16 vibrational modes. The algebraic Hamiltonian
, where A
i
, A
ij
and λ
ij
are the algebraic parameters which vary from molecule to molecule and C
i
, C
ij
and M
ij
are algebraic operators. The vibrational energy levels are calculated using algebraic model Hamiltonian and the results are
compared with the experimental values. The results obtained by this model are very accurate.
相似文献
20.