Synthesis of a new class of keto-linked bis heterocycles

A new class of keto-linked bis heterocycles have been prepared by 1,3-dipolar cycloaddition of tosyl methyl isocyanide, nitrile imines and nitrile oxides to unsymmetrical bischalcones.     

A note on the construction of certain BIB designs

In this note a method of construction of certain combinatorial designs is defined. This gives the solution of (121, 132, 60, 55, 27) which is marked as unknown by Kageyama [1].     

Spectrophotometric Determination of Ruthenium with 2-Amino-3-Hydroxypyridine

Ruthenium(III) complexation with 2-amino-3-hydroxpyridine is studied spectrophotometrically. The violet-red complex (λ_max 520 nm; ? 4460) contains metal and the ligand in 1 : 1 molar ratio, adheres to Beer's law from 0 to 16.5 µg/ml of ruthenium concentration and shows maximum and constancy in absorbance between pH 5.3 and 6.5. The complexation is used in the spectro-photometric determination of ruthenium in coexistence with several ions including some from platinum metals.     

Electron impact studies on 2-hydroxyimino-N-aryl acetamides

The mass spectra of 13 2-hydroxyimino-N-aryl acetamides contain abundant arylamine, isocyanate and protonated benzimidazole ions, the mechanisms of formation of which were established by deuterium labelling and formulae by exact mass measurements. Loss of OH˙ and NO˙ were postulated to proceed through cyclic and acyclic intermediates respectively. Considerable hydrogen scrambling and rearrangement could be noticed in all the processes.     

Rigidity spectrum of cosmic ray helium nuclei

An experiment has been carried out using an oriented stack of nuclear emulsions to determine the rigidity spectrum of cosmic ray helium nuclei between 12 and 40 GV, by taking advantage of the variation of the geomagnetic cut-off rigidity in the east-west plane over Hyderabad, India. Altotal of 2433 identified helium nuclei recorded in the stack, has been divided into 8 angular intervals in the east-west plane corresponding to 8 different cut-off rigidities. From this the integral fluxes of helium nuclei at the top of the atmosphere have been obtained for all the 8 rigidity intervals. The vertical flux above an effective threshold rigidity of 16·73 GV has been determined with high statistical accuracy and has a value of 15·0±0·5 helium nuclei (m².sr.sec.)^?1. The rigidity spectrum of these nuclei between 12 and 40 GV can be well represented by a power law of the type N (>R) =1990 R^?1.74±0.11 (m².sr.sec.)^?1 and is the first direct determination so far made in this rigidity region. The differential rigidity spectra of protons, helium nuclei and S-nuclei of the cosmic radiation in the vicinity of the earth at solar minimum (1965) have been constructed with the existing world data and it is found that for rigidities ? 10 GV, the three spectra have, within experimental errors, the same slope of 2·6. The ratio P/He and He/S of the differential fluxes have been studied as a function of rigidity. It is found that for R>2 GV, the ratio P/He has, within experimental errors, a constant value of 6·3; as for the ratio He/S, it seems that the experimental data above a GV is not inconsistent with a constant value of 14 over the entire rigidity interval considered here.     

Strong and decoupling structure in transitional odd-odd mass nuclei

The well known decoupling and strong coupling features of the high spin states in the transitional odd mass nuclei are found to persist also in the odd-odd mass nuclei. The simple structure of the levels borne out by the present calculations provides a straightforward understanding of the nature of the electromagnetic transitions.     

Differentiation of phase objects by spatial filtering

A filter function has been theoretically arrived at, which in a coherent optical system produces an irradiance image distribution that is quasi-linear to the first derivative of the phase of a purely phase varying object. The filter function is generated with the aid of a computer-controlled plotter and experimental results of phase differentiation are presented.     

Quadratic semigroups on affine spaces

As a generalization of some aspects of the theories of algebraic groups and finite dimensional algebras one can study polynomially defined, associative operations on affine spaces. In this paper we study the quadratic case—i.e., the case when the polynomials are of degree at most two. We call the resulting semigroup a quadratic semigroup. We obtain the complete structure for one class of quadratic semigroups and a representation theorem for another class.