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901.
Utso Bhattacharya Sayak Dasgupta Amit Dutta 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(10):216
We study the effect of a half wave rectified sinusoidal electromagnetic (EM) wave on the Kitaev honeycomb model with an additional magneto-electric coupling term arising due to induced polarization of the bonds. Within the framework of Floquet analysis, we show that merging of a pair of Dirac points in the gapless region of the Kitaev model leading to a semi-Dirac spectrum is indeed possible by externally varying the amplitude and the phase of the EM field. 相似文献
902.
903.
R. Mythili P. Singh P. K. Bhattacharya A. B. Parui M. G. Betigeri P. M. Raja Rao G. Krishnamurthy V. S. Raju 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,7(4):311-318
Oxygen ions from a 2 MV tandem accelerator have been used in beam-foil spectroscopic studies of O II, O III and O IV in the wavelength region 2000–5000 Å. Excitation functions for relative level populations in O II, O III and O IV in the incident energy range of 1.2–3.75 MeV have been measured and interpreted in terms of the independent electron model. Mean radiative lifetime measurements for a number of levels including cascades 4631 Å feeding to 2450 Å and 4344 Å feeding to 2385 Å in O IV have resulted in consistent values. Lifetime measurements for some of the O II levels of astrophysical interest have been reinvestigated and significant deviations from earlier values were observed. 相似文献
904.
905.
906.
The polymerization of acrylamide, initiated with permanganate/oxalic acid, has been studied at 35 ± 0.2 in an aqueous medium under nitrogen. Samples of polyacrylamide were fractionated by the triangular fractionation method using methanol as non-solvent. Molecular weights of the fractions have been determined by viscometry and osmometry. Integral and differential distribution curves were plotted using the fractionation data. The narrow molecular weight distribution for high conversion polymers has been discussed. For fractionated samples of polyacrylamide in water at 30°, the equation is applicable for the molecular weight range 4 × 104 to 127 × 104. This equation is very similar to the equation of Scholtan. Other parameters (osmotic second virial coefficient and unperturbed dimension) have also been evaluated. 相似文献
907.
Bhattacharya S Banerjee S Nayak SK Chattopadhyay S Mukherjee AK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(5):1099-1104
Molecular complex formation between [60]- and [70]fullerenes with a series of phosphine oxides, namely, tri-n-octyl phosphine oxide, triphenyl phosphine oxide and tri-n-butyl phosphine oxide has been studied in CCl4 medium by NMR spectrometric method. Both [60]- and [70]fullerenes have been shown to form 1:1 adducts with the above series of phosphine oxides. Formation constants (K) for all the complexes have been determined from the systematic variation of NMR chemical shifts of specific protons of the donors in presence of [60]- and [70]fullerenes. Trends in the values of K suggest that [70]fullerene binds stronger with the phosphine oxides relative to [60]fullerene. 相似文献
908.
J. Bhattacharya S. K. Chakravarti S. Talapatra S. K. Saha S. C. Guhaniyogi 《Journal of polymer science. Part A, Polymer chemistry》1989,27(12):3977-3983
Initiation of polymerization of methyl methacrylate with redox system montmorillonite (with lattice Fe3+)–thiourea has been achieved. The rates are dependent on both clay mineral and thiourea. Amidosulfenyl radicals are believed to initiate the polymerization on the clay surface. The polymerization produced nonextractable clay–polymer adduct up to an extent of 70 wt %. The pH of the medium (in the acidic range) did not affect the polymerization rate. 相似文献
909.
S. D. Singh W. G. Devi A. K. M. Singh M. Bhattacharya P. S. Mazumdar 《Journal of Thermal Analysis and Calorimetry》2000,61(3):1013-1018
A technique has been developed for the calculation of the ∫T
0
T′mexp(–E/RT′)T′.
The accuracy of the method is tested by comparing its predictions with numerical results and those of a method due to Quanyin
and Su.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
910.
In the present investigation, polycrystalline semiconductor Cd–Se–Te films have been electrodeposited at room temperature on conducting glass substrates using cyclic voltammetric technique under controlled periodic scans. The successive anodic and cathodic scans were recorded within the potential range, from 0 to −1.0 V, and over the range of periodic cycles, from 250 to 2,000, in an acidic bath containing respective reducible precursor ions like Cd2+, Se4+, Te4+, and 1 vol.% Triton X-100 as the surface-active reagent. Thin composite films were produced having variable thickness and composition and grain size of the order of 80–100 nm. The film properties were determined by focused ion beam analysis, energy dispersive analysis of x-rays, x-ray diffraction studies, atomic force microscopy, and scanning electron microscopy. Thickness of the semiconductor films was found to increase linearly with the number of voltammetric cycles. Band gap energies of the films as derived from the reflectance spectra were found to lie between 1.4 and 1.7 eV. The composite films of the Cd–Se–Te ternary system when electrochemically characterized in aqueous polysulfide solution exhibited n-type semiconducting properties and photoconversion efficiency more than 0.4%. 相似文献