The influence of instrumental analysis, i.e., physicochemical methods, has become increasingly important in organic chemistry, but organic elemental microanalysis is by no means an obsolete field. On the contrary, with the development of new methods, the organic chemist obtains the results that he needs for a first orientation on a compound, more quickly and more reliably than ever before. Toda...

Introduction: Niobium and tantalum are generally regarded to be lithophile incompatible elements occurring in chondritic relative proportions in planetary materials [1]. Precise Nb/Ta data have indicated that Nb may be depleted in the Earth's mantle [2, 3] which may be evidence for sequestering in an eclogite reservoir [2], or for its removal into the core [3, 4]. Metal-silicate partitioning ex...

EPMA has been applied to electron beam evaporated and r.f. sputtered layers of about 200 tig/cm. This includes analysis of trapped argon and oxygen ranging from 0.2 to 10 wt%. For primary electron energies of 5 to 15 keV depth range of X-ray emission may be predicted with an accuracy of ± 10 nm. Errors of quantitative analysis are discussed for various correction models and should not exceed 3....

Few other analytical methods have expanded so rapidly as electron probe microanalysis during the past 10 years. The number of elements that can be determined or detected extends from beryllium to uranium and concentrations in the range 0.1—100 per cent can be dealt with. This has been made possible by the introduction of new analysing crystals and counting systems. The application of computer p...

This paper presents a description of the state of the art methodology and software for the application of x-ray microanalysis to thin surface layers and more generally to the characterization of stratified specimens. The sensitivity of the technique to near-surface segregation is demonstrated. Some emphasis is given on the eS(pz) function (the distribution in depth of the primary generated x-ra...