Cosmic ray nuclei of chargeZ⩾3 during the period of low solar activity

A detailed study of the composition and energy spectra of heavy nuclei of charge Z?3 in the primary cosmic rays has been made during the period of low solar activity, using two stacks of nuclear emulsions exposed in balloon flights from Fort Churchill, Canada, in June 1963. Each of the stacks was composed of 120 nuclear emulsions of three different sensitivities and was exposed at about 3·5 g. cm.^?2 of residual air for about 11.1 hr. Reliable resolution of charges of nuclei from lithium to oxygen was obtained; for heavier nuclei, charge groups were determined. From the analysis of 793 tracks of nuclei with Z?3, results on the following aspects were obtained:

1. The differential energy spectra of L (Z=3–5), M (Z=6–9) and H (Z=10–28) nuclei were measured in the energy intervel 150–600 MeV/nucleon; integral fluxes were obtained for energy >600 MeV/nucleon;
2. The energy dependence of the L/M ratio at the top of the atmosphere was determined; the ratios were obtained as 0·45 ± 0·06 and 0·29 ± 0·03 in the energy intervals of 200–575, and >575 MeV/nucleon respectively;
3. Relative abundances of individual nuclei of Li, Be, B, C, N and O at the top of the atmosphere were determined as 36, 29, 55, 100, 60 and 106 respectively in the energy interval 150–600 MeV/nucleon; corresponding values were also obtained for energy >600 MeV/nucleon.
4. The differential fluxes of multiply charged nuclei measured by us and by other investigators were used to determine the solar modulation between solar maximum to solar minimum. It was found that solar modulation of the fluxes of M and He nuclei were consistent with Rβ dependence and that the modulation parameter Δη between 1965 and 1957 was about 1·1.

The implications of these results are discussed.     

Synthesis of some new mesoionic heterocycles

The synthesis of various substituted 1-hydroxy-2-chloroacetyl-6-thia-10b-aza-2a-azoniaaceanthrylene hydroxide inner salt, 1-hydroxy-6-thia-10b-aza-2a-azoniaaceanthrylene hydroxide inner salt, 1-hydroxy-2-piperidinoacetyl-6-thia-10b-aza-2a-azoniaaceanthrylene hydroxide inner salt is described. The ir is also included.     

Xanthate anions in salts of biscyclopentadienylzirconium(IV) chelates

A series of [Cp ₂ZrL]⁺[ROCS₂]^? complexes whereL is the conjugate base of acetylacetone, benzoylacetone or 8-hydroxyquinoline andR=Me,Et ori-Pr have been synthesised in aqueous medium by the reaction of [Cp ₂ZrL]⁺Cl^? withROCS ₂ ^? K⁺. Various physico-chemical studies carried out for these complexes indicate that all the complexes are 1:1 electrolytes in which the ligandL is bidentate, consequently there is a tetrahedral coordination about the zirconium atom.     

Uranium oligomerization in chloride-based high temperature melts: in situ XAS studies

In situ EXAFS spectroscopic studies of uranium compounds in high temperature alkali chloride melts indicate the presence of oligomeric species. An investigation into UCl(3) and UCl(4) dissolved in LiCl reveals long range ordering of uranium atoms in the molten state which is not maintained on quenching. Studies of uranium dioxide dissolved in LiCl-KCl eutectic with HCl exhibit long range ordering in both molten and quenched states, and the EXAFS data can be modeled using multiple coordination shells.     

Cuprophilic and pi-stacking interactions in the formation of supramolecular stacks from dicoordinate organocopper complexes

The unsupported organocopper pyridine complexes C6F5Cu(py) (2) and [C6F5Cu]2(4,4'-bipy) (3) form supramolecular structures that are unprecedented in organocopper chemistry; one-dimensional chains of copper atoms with Cu...Cu distances of 2.8924(3) angstroms in the blue-luminescent complex are likely associated with cuprophilic interactions, whereas multiple perfluoroarene-arene interactions dominate in the supramolecular assembly of 3.     

Stable theories, pseudoplanes and the number of countable models

We prove that if T is a stable theory with only a finite number (>1) of countable models, then T contains a type-definable pseudoplane. We also show that for any stable theory T either T contains a type-definable pseudoplane or T is weakly normal (in the sense of [9]).     

IS the ‘8° K’ background radiation universal?

The high energy gamma-ray flux (energy greater than 10¹² eV) resulting from high energy protons interacting with photons of the recently observed sub-millimeter microwave radiation in metagalactic space is calculated. Comparison of the flux of these gamma-rays with experimental observations indicate that the observed sub-millimeter radiation may not be universal.     

Inverse spectral theory for Jacobi matrices and their almost periodicity

In this paper we consider the inverse problem for bounded Jacobi matrices with nonempty absolutely continuous spectrum and as an application show the almost periodicity of some random Jacobi matrices. We do the inversion in two different ways. In the general case we use a direct method of reconstructing the Green functions. In the special case where we show the almost periodicity, we use an alternative method using the trace formula for points in the orbit of the matrices under translations. This method of reconstruction involves analyzing the Abel-Jacobi map and solving of the Jacobi inversion problem associated with an infinite genus Riemann surface constructed from the spectrum.