Model of a Monopulse Radar Tracking System for Student Laboratory

Development, construction and testing of a student laboratory model of the radar system that can be used for monopulse tracking is described. The laboratory model is simple and can be assembled from the existing equipment while the missing parts can be manufactured in a basically equipped RF electronics workshop. The laboratory model is used for student laboratory exercises as a part of a basic course on radar systems. The system is based on a Σ-Δ hybrid for processing signals obtained from two antennas. The composition of the model is described. Student exercises and measurements on the model are proposed. Alternative instruments which can be used in the model are considered. Possible improvements of the model are discussed

Existing and emerging cyanocidal compounds: new perspectives for cyanobacterial bloom mitigation

To help ban the use of general toxic algicides, research efforts are now directed towards the discovery of compounds that are specifically acting as cyanocides. Here, we review the past and look forward into the future, where the less desirable general algicides like copper sulphate, diuron or endothall may become replaced by compounds that show better specificity for cyanobacteria and are biodegradable or transform into non-toxic products after application. For a range of products, we review the activity, the mode of action, effectiveness, durability, toxicity towards non-target species, plus costs involved, and discuss the experience with and prospects for small water volume interventions up to the mitigation of entire lakes; we arrive at recommendations for a series of natural products and extracted organic compounds or derived synthetic homologues with promising cyanocidal properties, and briefly mention emerging nanoparticle applications. Finally, we detail on the recently introduced application of hydrogen peroxide for the selective killing of cyanobacteria in freshwater lakes