The multi-configuration Dirac-Fock calculation of the low-lying levels of Sm

The excitation energies and hyper-fine structure constants of the low-lying levels of Sm atom are calculated using the multi-configuration Dirac-Fock (MCDF) method. The results show that the excitation energies of the ground state multiplets can be calculated accurately using a small orbital set but the higher levels need larger orbital sets. Similar inference can also be drawn from the discrepancy between the calculated values of the hyper-fine constants and the experimental data. A sequence of MCDF calculation demonstrates the effect of the MCDF potential on the orbitals. Among the rare earth atoms Sm is a promising candidate for discrete symmetry violation experiments in atoms. This makes accurate theoretical calculations necessary since parameters in particle physics can be derived by combining the experimental results with the theoretical results. And these could be a probe for the physics beyond the standard model. Received 10 October 2000 and Received in final form 23 January 2001     

On Bivariate Lack of Memory Property and a New Definition

The earlier concept of bivariate lack of memory property has been examined and an alternative concept of bivariate lack of memory property has been presented along with a set of equivalent conditions. In this process, the link relations known in the literature on univariate lack of memory property have been extended to the bivariate set-up. A multivariate extension of the lack of memory property has also been proposed.     

Working group report: High energy and collider physics

This is a summary of the projects undertaken by the working group I on high energy and collider physics.     

Diastereoselective alkylations of β-tetrazolyl propionic acids

A new procedure for the diastereoselective alkylations of β-tetrazolyl propionic acids is described. A seven-membered chelation model is proposed to rationalize the observed high level of syn selectivity.     

Copper nanoparticles catalyzed N-H functionalization: An efficient solvent-free N-tert-butyloxycarbonylation strategy

A chemoselective transformation of amines to their tert-butyloxycarbonyl (Boc) protected derivatives (NBoc) is described using Cu-NPs under solvent-free conditions. Simple method, rapid reaction rate, mild conditions, tolerance of a wide range of functional groups, excellent yield, ease recovery and high catalytic turnover are the salient features of this approach. tert-Butyloxycarbonylation of chiral amino acid esters and amino alcohols were performed without racemization.     

Synthesis and antibacterial activity of isochromene and isoquinoline derivative

Synthesis of 4‐thioureidobenzoic acid ( 2 ), which on cyclization with ethyl chloroacetate gave 4‐(2‐imino‐5‐oxothiazolidin‐3‐yl)‐benzoic acid ( 3 ), which on further reacting with benzoin ( 4 ) in the presence of polyphosphoric acid afforded the synthesis of 2‐imino‐3‐(‐1‐oxo‐3,4‐diphenyl‐1H‐isochromen‐6‐yl) thiazolidin‐5‐one ( 5 ). Compound 5 was then reacted with substituted anilines to give 6‐(2‐imino‐5‐oxothiazolidin‐3‐yl)‐3,4‐diphenyl‐2‐(substituted)‐isoquinolin‐1(2H)‐one (6). The structures of the compounds have been elucidated on the basis of IR 1HNMR, 13C NMR, and elemental analysis. Representative samples were screened for their antimicrobial activity against gram‐negative bacteria, E. coli and P. aeruginosa and gram‐positive bacteria, S. aureus, and C. diphtheriae using disc diffusion method. J. Heterocyclic Chem., (2011).     

All-optical parallel data and address recovery scheme

In this paper, we have presented a parallel system model to recover data and address based on terahertz optical asymmetric demultiplexer (TOAD)/semiconductor optical amplifier (SOA)-assisted Sagnac gate. The architecture is based on a system which has its input information containing data and address. Here, we first convert the original data into a coded form with the help of input address. Then the coded information is transmitted through the optical routing channel. At the receiver end, the model simultaneously extracts data and address at any point of the routing channel. The operations of the circuits are studied theoretically and analyzed through numerical simulations. The variation of contrast ratio, amplitude modulation, extinction ratio and bit error rate with control pulse energy and switching crosstalk with gain ratio has been thoroughly investigated.     

Reactions of a Cyclenphosphoranide Platinum (II) Complex and the Role of Highly Nucleophilic Substituents at the Axial Positions of a Trigonal Bipyramid

Abstract

(η²-cyclenP)Pt(Cl)PPh₃ 1 exhibits a large variety of selective reactions due to the platinum metal and cyclenphosphoranide ligand, cyclenP. Moreover, the cyclenP ligand is capable of altering many of the usual reactions and/or mechanisms at square planar platinum (II) complexes.