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121.
Paragmay Chatterjee Asok Kumar Bandyopadhyay Pratul Bandyopadhyay 《General Relativity and Gravitation》1986,18(11):1127-1140
It is shown that as Riemannian space may be taken to give rise to a Poincaré gauge theory of gravitation, the superspace where the coordinates are given by (X, ), being a spinorial variable gives rise to anSL(2, C)-gauge theory and corresponds toN= 1 supergravity. It leads to a conserved current and the conserved quantity here corresponds to isospin, where the latter is taken to be generated from conformal reflection. Thus, supergravity plays a predominant role in the microlocal space-time. 相似文献
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Preparation and properties of several highly stable nitroso complexes of rhenium viz. ReCl3(NO), Re(OH)3(NO)3 M2ReCl5(NO) where M is Cs, K and NH4 are described. These are analogous to the corresponding ruthenium complexes. The oxidation number of the ‘ReNO’ unit as a whole, is +3 but that of the rhenium atom cannot be determined. The nitric oxide stretching band lies within the range of 1710–1920 cm?1. The cesium and potassium salts are weakly paramagnetic at room temperature. 相似文献
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Showalter BM Datta A Chowdhury PK Park J Bandyopadhyay P Choudhury PK Kesavan S Zeng Y Kraus GA Gordon MS Toscano JP Petrich JW 《Photochemistry and photobiology》2001,74(2):157-163
Using time-resolved infrared spectroscopy, ab initio quantum mechanical calculations and synthetic organic chemistry a region in the infrared spectrum of triplet hypericin has been found between 1400 and 1500 cm-1 corresponding to the translocation of the hydrogen atom between the enol and the keto oxygens, O...H...O. This result is discussed in the context of the photophysics of hypericin and of eventual measurements to observe directly the excited-state H-atom transfer. 相似文献
128.
The possible topological structures of elementary particles have been investigated to explore the possibility of the existence of magnetic monopoles. It is pointed out that when an elementary charged particle is depicted as an extended body such that the orientation of the internal space (internal helicity) defines the fermion number, the global conservation of this does not allow the existence of a magnetic monopole. Again it is argued that when anisotropy is introduced in the microlocal space-time depicting the internal space of hadrons, this gives rise to the internal symmetry algebra and no non-Abelian gauge fields and Higgs scalars are necessary to have a grand unified scheme of interactions. This avoids theSU
2 and GUT monopoles. Besides, in this formalism, baryon number corresponds to the orientation or internal helicity of the composite system and the global conservation of this quantum number is found to be a consequence of Lorentz invariance. This forbids the existence of any sort of cosmological monopole in this Lorentz invariant Universe. 相似文献
129.
Modern optical communication system requires multiple channel transmission in different spectral band for different applications. Here we are proposing a microresonator structure for closely spaced, mode independent multiple channel transmission in 3rd transmission window by controlling the localization of photons in its cavity. To design the proposed structure, the spectral filtering properties of a single cavity planar microresonator are studied initially. In conventional multilayer dielectric filter, the localization of light in the microcavity is generally controlled by controlling the number of layers. Here we have shown that application of electric field across the structure, designed with suitable materials can also affect the localization of light in the cavity as well as the Q values of the transmission spectra. The mode independent characteristic of the structure is found from the study of its transmittance characteristics at different angle of incidence of light. It is found that the results of single cavity structure hold well for multicavity resonator structure also, in the regime of optical communication wavelength range. A method to increase the number of transmission channels is also proposed here keeping the fabrication perspective in mind. 相似文献
130.
Choudhury Sayantan Pal Barun Kumar Basu Banasri Bandyopadhyay Pratul 《Journal of High Energy Physics》2015,2015(10):1-37
Journal of High Energy Physics - In this paper we study the production of a heavy charged Higgs boson in association with heavy quarks at the LHC in the two-Higgs-doublet model. We present for the... 相似文献