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991.
992.
D.P. Chakraborty R. Spal C.K. Chiang A.M. Denenstein A.J. Heeger A.G. MacDiarmid 《Solid State Communications》1978,27(9):849-853
The â-b? plane resistivity of the Hg-chain compound, Hg3?δAsF6, has been measured as a function of temperature and magnetic field using a contactless ac technique. The data imply a magnetic field dependent residual resistivity which goes to zero as the field is reduced to zero. The results are discussed in terms of the quasi-one-dimensional electronic and structural features of this novel linear chain compound. 相似文献
993.
H. S. Chakraborty 《Czechoslovak Journal of Physics》1969,19(8):936-940
The methods of transform calculus are made use of in finding the electrical response in a piezoelectric transducer due to shock-loaded stress. The response is found to be transient in character to a first order of approximation.The author is deeply indebted to Dr. D. K. Sinha for his constant guidance in preparing this paper. He also thanks the referee for his comments and suggestions for improving the paper. 相似文献
994.
The charged particle orbits in electromagnetic fields on Kerr background as viewed from a locally non-rotating frame do not
exhibit non-gyrating bound orbits, which was an essential feature in the earlier study of Prasanna and Vishveshwara, thus
showing the non gyration to be due to the effect of dragging of inertial frames produced by the rotating black hole. 相似文献
995.
996.
997.
Munmun Khatua Debdutta Chakraborty Pratim Kumar Chattaraj 《International journal of quantum chemistry》2013,113(13):1747-1771
The quantum domain behavior of classical nonintegrable systems is well‐understood by the implementation of quantum fluid dynamics and quantum theory of motion. These approaches properly explain the quantum analogs of the classical Kolmogorov–Arnold–Moser type transitions from regular to chaotic domain in different anharmonic oscillators. Field‐induced tunneling and chaotic ionization in Rydberg atoms are also analyzed with the help of these theories. Quantum fluid density functional theory may be used to understand different time‐dependent processes like ion‐atom/molecule collisions, atom‐field interactions, and so forth. Regioselectivity as well as confined atomic/molecular systems and their reactivity dynamics have also been explained. © 2013 Wiley Periodicals, Inc. 相似文献
998.
A. Chakraborty B. Das S. Findeisen-Tandel M.-G. Tamba U. Baumeister 《Liquid crystals》2013,40(9):1085-1097
New hockey stick-shaped mesogens with a lateral methyl group inserted between the m-alkyloxy-chain and the azomethine connecting group, 4-(3-n-alkyloxy-2-methyl-phenyliminomethyl) phenyl-4-n-alkyloxycinnamates have been synthesised. The interesting feature of these hockey stick-shaped mesogens is the appearance of the nematic phase in addition to two polymorphic tilted smectic phases – the synclinic smectic C (SmCs) and the anticlinic SmCa phase. Physical characterisation of these mesogens has been carried out using polarising optical microscopy, differential scanning calorimetry, optical birefringence, X-ray diffraction (XRD), electro–optical and dielectric spectroscopy measurements. The SmCs–SmCa phase transition is accompanied by only a small calorimetric signal but causes a pronounced change in the optical textures. Orientational order parameters determined from the birefringence measurements have been compared with those estimated from XRD patterns. Dielectric measurements point to the formation of small ‘soft’ ferroelectric clusters responsible for a low frequency absorption range. 相似文献
999.
The work utilized photoinduced electron transfer (PET) reactions to identify the preferred photoreaction route in molecules having juxtaposed α,β and β,γ-enones. Such process directly converted 2-hydroxyimino derivatives of 5-benzoylbicyclo[2.2.2]octenones to the corresponding bicyclo[3.2.1]octane derivatives. First evidence of Type B rearrangement in α,β-enones having acyl substitution at Cγ-position has been depicted in this work. In rigid mixed enones, this has been found to be generally the preferred photoreaction route. 相似文献
1000.
Sudeshna Mukerji Nairwita Mazumder Ritabrata Biswas Subenoy Chakraborty 《International Journal of Theoretical Physics》2011,50(9):2708-2719
In this work, Emergent Universe scenario has been developed in general homogeneous anisotropic model and for the inhomogeneous
LTB model. In the first case, it is assumed that the matter in the universe has two components—one is perfect fluid with barotropic
equation of state p=ωρ (ω, a constant) and the other component is a real or phantom (or tachyonic) scalar field. In the second case, the universe is
only filled with a perfect fluid and possibilities for the existence of emergent scenario has been examined. 相似文献