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71.
Different all-optical logic operations, memory blocks etc. are developed using the inherent parallelism of optics. In any digital communication and computation system, the role of serial to parallel and parallel to serial data conversion are very much essential for making a data convenient for transition.Here in this paper, the authors propose a new scheme for developing an all-optical parallel to serial data conversion system by using optical J-K Flip-Flops and some logic gates based on optical non-linear switches. The uses of such switches are widely established in the area of optical parallel computation.This process can be extend for developing some all-optical digital devices like shift register, optical pulse counters etc. The proposed scheme deals with the best use of high parallelism of the optics, so the super-fast processing speed can be achieved. 相似文献
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73.
Goutam Mukhopadhyay Jasmina Khanam Arunabha Nanda Arindam Basu Sarkar 《Chromatographia》2010,71(7-8):699-702
A simple, sensitive and precise reverse phase liquid chromatographic method has been developed and validated for quantification of bovine serum albumin (BSA), α-lactalbumin (α-La) and β–lactoglobulin (β-Lg) that are removed from whey waste by foam fractionation method. The data is reproducible over a wide concentration range. This optimized method allowed analysis of BSA, α-La, β-Lg in a mixture within 5 min and could be applied to the analysis of a variety of commercial and laboratory whey products within a short time. 相似文献
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76.
Prashant Dubey Devarajan Muthukumaran Subhashis Dash Rupa Mukhopadhyay Sabyasachi Sarkar 《Pramana》2005,65(4):681-697
Carbon nanotubes (CNT) has been synthesized by pyrolysing mustard oil using an oil lamp. It was made water-soluble (wsCNT)
through oxidative treatment by dilute nitric acid and was characterized by SEM, AFM, XRD, Raman and FTIR spectroscopy. The
synthesized wsCNT showed the presence of several junctions and defects in it. The presence of curved graphene structure (sp2) with frequent sp3 hybridized carbon is found to be responsible for the observed defects. These defects along with the presence of di- and tri-podal
junctions showed interesting magnetic properties of carbon radicals formed by spin frustration. This trapped carbon radical
showed ESR signal in aqueous solution and was very stable even under drastic treatment by strong oxidizing or reducing agents.
Oxidative acid treatment of CNT introduced several carboxylic acid group functionalities in wsCNT along with the nicking of
the CNT at different lengths with varied molecular weight. To evaluate molecular weights of these wsCNTs, an innovative method
like gel electrophoresis using high molecular weight DNA as marker was introduced. 相似文献
77.
This paper concerns with the investigation of laminar flow separation and its consequences in a tube over a smooth expansion under the axi-symmetric approximations. A co-ordinate stretching has been made to map the expanded tube into a straight tube. The two-dimensional unsteady Navier-Stokes equations are solved approximately by using primitive variables in staggered grid. A thorough quantitative analysis is performed through numerical simulations of the desired quantities such as wall shear stress, axial velocity, pressure distribution etc. These quantities are presented graphically and their consequences in the flow field are analysed in details. The dependence of the flow field on the physical parameter like expansion height d and on the Reynolds number has been investigated in details. It is interesting to note that the peak value of wall shear stress decreases with increasing height of expansion and also with the increasing Reynolds number. 相似文献
78.
Indranath Mukhopadhyay Romola D''Cunha K. Narahari Rao 《International Journal of Infrared and Millimeter Waves》2003,24(9):1441-1467
This paper presents a part of the culmination of the collective efforts in developing a cohesive and consolidated enunciation of the spectroscopic parameters and their relationship to effective molecular Hamiltonians for diatomic formalism, linear four-atomic formalism and quasi-linearity, Watson Hamiltonian and the complexities in symmetric and asymmetric top spectral structures. All these considered together present a beautiful and consistent picture of molecular spectroscopy. In this paper we deal with the diatomic formalism. This paper forms our tribute to Professor K. Narahari Rao and in the second part of the paper we convoy our gratitude to him with a summary of his more than half century of work and an obituary. We will deal with other forms of molecular species which will be connected to optical pumping and/or interstellar space. 相似文献
79.
Operational characteristics of a dual gain single cavity Nd:YVO4 laser have been investigated. With semiconductor diode laser pump power of 2 W, 800 mW output was obtained with a slope efficiency
of 49%. Further, by changing the relative orientation of the two crystals the polarization characteristics of the output could
be varied. In particular by keeping the two Nd:YVO4 crystals with their c-axes orthogonal to each other and adjusting the gain of the crystals so that both operate at approximately the same power
level, completely unpolarized beams could be obtained. 相似文献
80.
Sabari Ghosh Chhanda Mukhopadhyay 《Journal of inclusion phenomena and macrocyclic chemistry》2017,88(3-4):105-128
In this review, pseudorotaxanes and rotaxanes structured out of simple crown ethers and linear organic molecules with positively charged nitrogen centres (i.e., quaternary pyridinium groups, viologens like paraquat and also extended viologens, imidazolium groups, benzimidazolium groups, bis-benzimidazolium groups and their derivatives) are described. Some selected examples of such systems are assembled here with respect to their properties and applications. 相似文献