Equatorial ozone profiles from the solar maximum mission—a comparison with theory

The u.v. spectrometer polarimeter on the Solar Maximum Mission has been utilized to measure mesospheric ozone vs altitude profiles by the technique of solar occultation. Sunset data are presented for 1980, during the fall equinoctal period within ± 20° of the geographic equator. Mean O₃, concentrations are 4.0 × 10¹⁰ cm^?3at 50 km, 1.6 × 10¹⁰ cm^?3 at 55 km. 5.5 × 10⁹ cm^?3 at 60 km and 1.5 × 10⁹ cm^?3 at 65 km. Som profiles exhibit altitude structure which is wavelike. The mean ozone profile is fit best with the results of a time-dependent model if the assumed water vapor mixing ratio employed varies from 6 ppm at 50 km to 2–4 ppm at 65 km.     

Strained co-ordinate methods in rotating stars

It was shown in a previous paper, Smith (1975), that the determination of the structure of rotating polytropes by expansion in the small rotational parameter constitutes asingular perturbation problem as arises also, for example, in large Reynolds' number approximations in fluid dynamics. The technique used by him — the method of matched asymptotic expansions — is, in fact, just an extension of the Prandtl boundary layer theory familiar in this latter context. In this paper — the first of two — we introduce an alternative procedure: the method of strained co-ordinates; and for comparison purposes again consider rotating polytropes. In Paper II we extend this approach to differentially rotating stars and present an illustrative example.     

Evaluation of Nørsett methods for integrating differential equations in time

Some recently developed implicit time discretizations are discussed whose main application is to solving ordinary differential equations arising from finite element approximations to partial differential equations. Their theoretical properties, computer implementation and numerical behaviour, as observed in tests on simple examples, are compared with well-known discretizations such as the Crank-Nicholson method.     

The orbital periods of revolution of a satellite

The relationship between the anomalistic and nodal periods of revolution of a satellite is investigated and it is shown that the anomalistic period of revolution can change even in a conservative system of forces and it is suggested that the mean nodal period represents the energy of the satellite.     

THE CRACKING HISTORY OF SERRANIA DE VARAS: AN ALTERNATIVE VIEW

Buchwald's (1975) theory of thermally induced cracking in Serrania de Varas is critically examined from the standpoint of elementary stress analysis. New metallographic observations are presented. It is suggested that thermal cracking is unlikely to have been operating in this material.     

Geochemical prospecting for baryte and celestite using a portable radioisotope fluorescence analyser

A method is described for determining the Ba and Sr content of soils in the field laboratory using a portable, isotope source, X-ray fluorescence analyser. The application of these techniques to the exploration for vein-type barytes and stratiform celestite deposits in the west of England is described. Satisfactory accuracy is achieved in comparison with other methods, along with considerable economies in time and effort. Detection limits (2 × standard deviation) are 200–300 ppm for Ba and about 500 ppm for Sr.