& In an HPLC system the detector is the component responsible for turning a physical or chemical attribute into a measureable signal corresponding to concentration or identity. In the early days of HPLC, detection was often carried out by collecting fractions and analyzing them off-line. It wasn’t until the 1940’s and 1950’s that the first online detectors for HPLC were introduced. Certainly an...

background: radon and its daughters are amongst the most important sources of natural exposure in the world. soil is one of the significant sources of radon/thoron due to both radium and thorium so that the emanated thoron from it may cause increased uncertainties in radon measurements. recently, a diffusion chamber has been designed and optimized for passive discriminative measurements of rado...

background: separate radon and thoron measurements in soil are very important in assessment of internal exposure due to inhalation of such radioactive gases. materials and methods: in this study, a low cost, small size, passive diffusion chamber has been developed for simple measurement of radon-222 and radon-220(thoron) gases separately in soil. the diffusion chamber consists of two films and ...