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The allylic hydroperoxides obtained from the methyl ester of qinghao acid, catalyzed by copper(II) trifluoromethanesulfonate or trifluoromethanesulfonic acid, produce a thermally susceptible intermediate. The reaction proceeds through the formation of an enol intermediate. The intermediates are isolated by chromatography and are analyzed by low temperature 1H and 13C NMR spectroscopy.

The Numerical Electromagnetics Code (NEC) is used to simulate the radiators of a skeletal biconical antenna and the model is optimized to return a drive point impedance as close as possible to measured values. The horizontally polarized model is then illuminated in free space and above a ground plane to deduce its plane-wave antenna factors and their variations as functions of height. It is shown that changes in effective length have to be considered in addition to changes in impedance mismatch when calculating antenna factor variations with the biconical antenna, although only the latter are necessary with a resonant dipole. The measured scattering parameters of the balun of the biconical antenna are then incorporated with the NEC simulation to give a complete model of the real antenna.

Abstract Background The development of new wireless communication technologies that emit radio frequency electromagnetic fields (RF-EMF) is ongoing, but little is known about the RF-EMF exposure distribution in the general population. Previous attempts to measure personal exposure to RF-EMF have used different measurement protocols and analysis methods making comparisons between exposure situations across different study populations very difficult. As a result, observed differences in exposure levels between study populations may not reflect real exposure differences but may be in part, or wholly due to methodological differences. Methods The aim of this paper is to develop a study protocol for future personal RF-EMF exposure studies based on experience drawn from previous research. Using the current knowledge base, we propose procedures for the measurement of personal exposure to RF-EMF, data collection, data management and analysis, and methods for the selection and instruction of study participants. Results We have identified two basic types of personal RF-EMF measurement studies: population surveys and microenvironmental measurements. In the case of a population survey, the unit of observation is the individual and a randomly selected representative sample of the population is needed to obtain reliable results. For microenvironmental measurements, study participants are selected in order to represent typical behaviours in different microenvironments. These two study types require different methods and procedures. Conclusion Applying our proposed common core procedures in future personal measurement studies will allow direct comparisons of personal RF-EMF exposures in different populations and study areas.

A correction is presented to the article "A Source-Based Measurement Database for Occupational Exposure Assessment of Electromagnetic Fields in the INTEROCC Study" which appeared in the previous issue.

Charlotte Walker-Osborn, Simon and Vicky Mann from Eversheds, outline some of legal issues to consider as well as the some of the pitfalls to be avoided and obstacles to be navigated when considering the implementation of a Bring Your Own Device programme in a work organisation. [ABSTRACT FROM AUTHOR]