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141.
142.
An efficient method for the synthesis of substituted isoquinolinium salts from benzaldehydes, amines, and alkynes via ruthenium-catalyzed C-H bond activation and annulation in one pot is described. 相似文献
143.
Kalpana Murugesan Govindan Kadarkarai Selvasekarapandian Subramanian Premalatha Manavalan Senthil Kumar Parthasarathy 《Ionics》2017,23(10):2621-2629
Modified Pechini-type polymerizable precursor method has been used to prepare nanosized Li1-xTbxNiPO4 (x = 0, 0.03, 0.05, and 0.07) solid solutions to obtain homogeneous with controlled stoichiometry and smaller particle size. The reaction temperature was determined by thermogravimetric (TG/DTA) analysis. X-ray diffraction analysis reveals the formation of orthorhombic structure and the calculated crystallite sizes are found to be in the range of 75–89 nm. Morphological, compositional, and vibrational properties were performed by SEM, EDAX, and FTIR, respectively. Conductivity measurements were carried out at room temperature by AC impedance analysis. The Li0.97Tb0.03Ni0.99PO4 sample shows one order of higher conductivity than pure LiNiPO4. Higher concentration of terbium samples such as Li0.95Tb0.05Ni0.99PO4 and Li0.93Tb0.07Ni0.99PO4 lead to decrease of conductivity. The frequency dependency of dielectric permittivity, dielectric loss, and electric modulus of Li1-x TbxNiPO4 solid solutions are studied. The frequency-dependent plot of modulus reveals that the conductivity relaxation is of non-Debye type. 相似文献
144.
Electron and x-ray diffraction studies on Al86Fe14, Al82Fe18 and Al75Fe25 quasicrystals 总被引:1,自引:0,他引:1
J A Sekhar T Rajasekharan P Rama Rao G Parthasarathy S Ramkumar E S R Gopal C S Lakshmi R M Mallya 《Pramana》1986,27(1-2):267-273
Electron and x-ray diffraction experiments on the metlt-spun Al100−x
Fe
x
(x=14, 18, 25) alloys are carried out. It is observed that all the melt-spun alloys possessing the quasi-crystalline phases
have icosahedral point-group symmetry.
The authors felicitate Prof. D S Kothari on his eightieth birthday and dedicate this paper to him on this occasion. 相似文献
145.
146.
K. R. Parthasarathy 《Letters in Mathematical Physics》1978,2(5):413-415
Summary The exact bound of the Coulomb potential with respect to the self adjoint Dirac operator is evaluated. 相似文献
147.
The process μ−+12C→12B+v
μ is studied using the modified Hartree Fock wavefunction obtained with the unitary-model-operator-approach starting from the
realistic hardcore nucleon-nucleon interaction, with the aim of testing the wavefunctions and obtaining a numerical value
for the induced pseudoscalar coupling constant (g
P
). These observables, namely, the partial capture rate to the12B(1+; g.s), its recoil nuclear polarisation and the total capture rate, which exhaust the available experimental data in the above
process have been calculated and compared with the other theoretical and experimental results.
As far as the partial capture rate is concerned the use of the unitary-model operator approach wave functions for12C withb=2.09 fm and Cohen-Kurath wave function for12B(1+; g.s) reduces the pure shell model capture rate by about 30%. The effect of strong configuration mixing in the ground state
of12C in taken into account by introducing a scale factor ξ similar to the ‘amplitude reduction factor’ of Donnelly and Walecka.
With this ξ the agreement with the experiment both for the partial capture rate and the beta decay ‘ft’ value is found to
be satisfactory.
The12B(1+; g.s) recoil polarisation is found to be insensitive to the use of the unitary-model-operator-approach wave functions. When
compared with the experimental data, we obtaing
P
=(14.9±1.9)g
A
.
The total capture rate is found to be sensitive to the use of the unitary-modeloperator-approach wave functions which contain
the effect of nucleon-nucleon short range correlations and we obtain a satisfactory agreement with the experiment for16O and12C, thereby revealing the importance of the effect of such correlations in the total capture rate studies. 相似文献
148.
149.
A general construction procedure for geodetic blocks, starting from an arbitrary geodetic block is given, which unifies and generalizes many of the known general procedures. The construction of geodetic blocks homeomorphic to a given one is also analysed and the problem of Bosák on the existence of such a graph for the Hoffman-Singleton graph is settled in the affirmative. A simple characterization theorem for geodetic blocks is given and the existence of geodetic blocks with given girth and diameter is investigated. 相似文献
150.
V. Parthasarathy S. K. Sarkar K. K. Pushpa K. A. Rao K. V. S. Rama Rao J. P. Mittal 《Applied physics. B, Lasers and optics》1993,56(2):101-103
IR laser chemistry of CHF3 is investigated in both neat form and in the presence of Cl2 for carbon-13 enrichment. Infrared multiple-photon dissociation of CHF3 is an order of magnitude more efficient in the scavenged system compared to the neat case. The photolysis of CHF3/Cl2 mixture results in two products, viz., CF2Cl2 and C2F4Cl2 but with different enrichment factors. The parametric studies show that C2F4Cl2 arises due to MPD of CF2Cl2 in secondary photolysis. 相似文献