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101.
U. Mahanta 《The European Physical Journal C - Particles and Fields》2001,21(1):171-173
Recently BNL have measured the muon magnetic moment anomaly with increased precision. The world average experimental value
at present shows a discrepancy of from the standard model (SM) value. In this paper we investigate the implications of this difference on a class of scalar
leptoquark interactions to SM quark–lepton pair. We find that for a leptoquark mass of a few hundred GeV the BNL muon anomaly
can arise from couplings much smaller than even the electromagnetic coupling. We also find that the BNL value for the muon
anomaly leads to an unambiguous prediction for the electric dipole moment of the muon and a bound on the flavor changing leptoquark
coupling relevant for the rare decay .
Received: 15 April 2001 / Published online: 6 July 2001 相似文献
102.
On a Class of Generalized Lacunary Difference Sequence Spaces Defined by Orlicz Functions 总被引:1,自引:0,他引:1
In this article we introduce the generalized lacunary difference sequence spaces [N_θ,M,Δ~m]_0,[N_θ,M,Δ~m]_1 and [N_θ,M,Δ~m]_∞using m~(th)- difference.We study their properties like completeness,solidness,symmetricity.Also we obtain some inclusion relations involving the spaces [N_θ,M,Δ~m]_0,[N_θ,M,Δ~m]_1 and[N_θ,M,Δ~m]_∞and the Cesàro summable and strongly Cesàro summable sequences. 相似文献
103.
B. Mukhopadhyaya S. Raychudhuri K. Agashe B. Allanach D. Bailin B. Brahmachari U. Chattopadhyay D. Choudhury P. Das Amitava Datta Anindya Datta A. Djouadi A. Giri K. Huitu A. Kundu U. Mahanta S. Moretti B. Mukhopadhyaya J. C. Pati A. K. Ray A. Raychaudhuri S. Raychaudhuri P. Roy N. Singh R. Vaidya 《Pramana》2003,60(2):395-399
104.
The size effect on electrical conduction is observed in bismuth films in the region of film thickness above 2000 Å. Applying Fuchs-Sondheimer theory and assuming specularity parameterp = 0·8, the value of bulk resistivity and mean free path are obtained as 6·692 × 104 ohm-cm and 6000 Å respectively. 相似文献
105.
Paul BK Mahanta S Singh RB Guchhait N 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(1):197-205
A structurally simple Schiff base N-benzyl-(3-hydroxy-2-naphthalene) (NBHN32) has been synthesized and characterized by (1)H NMR, (13)C NMR, and DEPT spectroscopy. The photophysical behaviour of NBHN32 in response to the presence of various transition metal cations has been explored by means of steady-state absorption, emission and time-resolved emission spectroscopy techniques. Efficient through space intramolecular photoinduced electron transfer (PET) between the naphthalene fluorophore and the imine group has been argued for extremely low fluorescence yield of NBHN32 compared to the parent molecule 3-hydroxy-2-naphthaldehyde (HN32) containing the same fluorophore but lacking the receptor moiety. Transition metal ion-induced emission enhancement is thus addressed on the lexicon of perturbation of the PET by the metal ions. Apart from fluorescence enhancement, transition metal ion imparts remarkable shift of the emission maxima of NBHN32, which is another unique aspect on the proposed ability of NBHN32 to function as a fluorescence chemosensor. 相似文献
106.
Subrata Mahanta Bijan Kumar Paul Rupashree Balia Singh Nikhil Guchhait 《Journal of computational chemistry》2011,32(1):1-14
The inequivalence of substitution pair positions of naphthalene ring has been investigated by a theoretical measurement of hydrogen bond strength, aromaticity, and excited state intramolecular proton transfer (ESIPT) reaction as the tools in three substituted naphthalene compounds viz 1‐hydroxy‐2‐naphthaldehyde (HN12), 2‐hydroxy‐1‐naphthaldehyde (HN21), and 2‐hydroxy‐3‐naphthaldehyde (HN23). The difference in intramolecular hydrogen bond (IMHB) strength clearly reflects the inequivalence of substitution pairs where the calculated IMHB strength is found to be greater for HN12 and HN21 than HN23. The H‐bonding interactions have been explored by calculation of electron density ρ(r) and Laplacian ?2ρ(r) at the bond critical point using atoms in molecule method and by calculation of interaction between σ* of OH with lone pair of carbonyl oxygen atom using NBO analysis. The ground and excited state potential energy surfaces (PESs) for the proton transfer reaction at HF (6‐31G**) and DFT (B3LYP/6‐31G**) levels are similar for HN12, HN21 and different for HN23. The computed aromaticity of the two rings of naphthalene moiety at B3LYP/6‐31G** method also predicts similarity between HN12 and HN21, but different for HN23. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010 相似文献
107.
It is shown that homogeneous plane symmetric string cosmological model for Takabayasi string i.e. ρ=(1+ω)λ does not exist in Barber’s second self creation theory. Further it is found that the string cosmological model in this theory
exist only when ω=0. Therefore model for ρ=λ (geometric string) is constructed. Some physical and geometrical properties of the model are discussed. 相似文献
108.
In the present work, an attempt has been made to assess the bioconcentration and distribution of zinc on the selected organs of Labeo rohita and to study the effect of zinc exposure on the biochemical constitutions of gill tissues of L. rohita by using FT-IR Spectroscopy. The concentration pattern in the organs reveals that the liver is the prime site of metal binding and muscle accumulates least metal concentration. The accumulation profile is in the order: liver > gill > kidney > brain > bone > muscle. It has also been observed that the administration of chelating agent d-Penicillamine (DPA) reduces the zinc concentration in all tissues more effectively than the administration of the chelating agent Ethylene Diamine Tetra Acetic acid. The FT-IR spectra reveal that zinc exposure causes significant changes in the biochemical constitutions of the gill tissues. It causes an alteration in the protein secondary structures by decreasing the α-helix and increasing the β-sheet contents. Further, it has been observed that the administration of chelating agent DPA improves the protein and lipid contents in the gill tissues compared to zinc exposed tissues. This result shows that DPA is the effective chelator of zinc in reducing the body burden of L. rohita fingerlings. In conclusion, the findings of the current study suggest that zinc exposure causes significant changes in both lipids and proteins of the gill tissues, and changes the protein profile in favour of β-sheet structure. 相似文献