Symmetric Multiplets in Quantum Algebras

We consider a modified version of the coproduct for \U(\su_q(2)) and show that in the limit when $q \rightarrow 1$, there exists an essentially non-cocommutative coproduct. We study the implications of this non-cocommutativity for a system of two spin-$1/2$ particles. Here it is shown that, unlike the usual case, this non-trivial coproduct allows for symmetric and anti-symmetric states to be present in the multiplet. We surmise that our analysis could be related to the ferromagnetic and antiferromagnetic cases of the Heisenberg magnets.Comment: Needs subeqnarray.sty. To be published in Mod Phys Lett.

High bat (Chiroptera) diversity in the Early Eocene of India

The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe, the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene

Resonance energy transfer from a fluorescent dye molecule to plasmon and electron-hole excitations of a metal nanoparticle

We study the distance dependence of the rate of electronic excitation energy transfer from a dye molecule to a metal nanoparticle. Using the spherical jellium model, we evaluate the rates corresponding to the excitation of l = 1, 2, and 3 modes of the nanoparticle. Our calculation takes into account both the electron-hole pair and the plasmon excitations of the nanoparticle. The rate follows conventional R^-6 dependence at large distances while small deviations from this behavior are observed at shorter distances. Within the framework of the jellium model, it is not possible to attribute the experimentally observed d^-4 dependence of the rate to energy transfer to plasmons or e-h pair excitations.Comment: 4 figure

Re-design of drivers’ car seat using three dimensional reverse engineering

Automobile seat design in current practice requires satisfying the ergonomics guidelines as well as considers the comfort expectation of the population. The main aim is to re-examine the existing car seat designs and to propose a novel seat design for better comfort. The number of cars reviewed for drivers’ seat features and user comfort are based on the analysis using a statistical tool. The statistical tool analysis is defined using data from the survey conducted. The proposed design is obtained using the 3-D Reverse Engineering procedure on the selected car seat models. The result is assessed to show that the modified car seat design is superior in terms of form, shape, seat features, usability and comfort. Through this work, the basic seat needs while driving, for example pain preclusion aspects and comfort weightage are defined. The survey done can expunge the expenditure for test experimentations in the future and the proposed methodology can be useful in establishing new design standards for the seat

Kinetics of Ag(I) Catalysed Oxidation of Isoamyl Alcohol by Peroxydisulphate

40-4

Kinetics & Mechanism of Ag+-catalysed Oxidation of Glyoxal & Glyoxaiic Acid by Peroxydisulphate in Aqueous Medium

1117-111