Applied Spectroscopy Reviews

Bailey, R. T.; Cruickshank, F. R.

doi: 10.1080/05704927508085061pmid: N/A

Abstract There have been a number of recent reviews dealing with various aspects of laser excited IR fluorescence [1–4]. The rapidly developing interest in this field has arisen in part from the realization of the importance of experimental information regarding the intermolecular forces and collision mechanisms which govern the interactions between molecules. Without these data, the various theoretical treatments of molecular relaxation and energy transfer cannot be tested in a meaningful fashion. The need of the laser physicist for fundamental energy transfer data in molecular systems has added impetus to the rapid expansion of this field. The parallel development of IR laser systems, both discrete frequency and tunable, together with advances in instrumentation in the IR region has also contributed to the development of IR fluorescence. Interest in the theoretical aspects of energy transfer is also increasing. Calculations of energy transfer cross-sections are, however, still hampered by the complexity of the problem, which makes it difficult to include physically realistic intermolecular potentials in the calculations. The problem rapidly becomes intractable for any but the simplest systems, and approximations are necessary if any progress is to be made. More work is needed to verify the validity of many of the approximations in current usage.

Falkner, Fred C.; Sweetman, Brian J.; Watson, J. Throck

doi: 10.1080/05704927508085062pmid: N/A

Abstract In 1961 Henneberg [1] employed selected ion monitoring (SIM) to study hydrocarbons eluting from a gas chromatographic column, and in 1966 the first biological application was reported by Sweeley, Elliott, Fries, and Ryhage [2]. Since these efforts and the early impetus given by Hammar, Holmstedt, and co-workers [3–6], SIM has found widespread application in biological, medicinal, and environmental research. Recent review articles have described ion monitoring work with magnetic sector instruments [7,8,8a,8b], quadrupole instruments [9], and time-of-flight instruments [19]. These articles provide comprehensive coverage of applications through 1972. This review emphasizes medicinal and biological applications through 1973 and attempts to evaluate current methods and recent developments.

Harris, Robin K.; Kimber, Barry J.

doi: 10.1080/05704927508085063pmid: N/A

Abstract Compounds containing the Si—O—Si linkage are important both in geochemistry and for commercially produced materials. They occur in a wide range of physical states; it is particularly common to find them as “pseudo-solids,” i.e., as glasses, gels, rubbers, and resins. Unfortunately, it has not been easy to obtain detailed information about molecular structure and motion for silicones. This is partly due to the complexity of many of the systems—for instance, a typical commercially produced silicone fluid contains a range of species with various molecular weights. Effects of copolymerization, tacticity, cross-linking, and segmental motion may complicate matters.