background: this study consists of two parts. the first part deals with both qualitative and quantitative analysis of 226ra using alpha spectrometry measurement method. in the second part, the percentage of radioactive equilibrium between 226 ra and its daughter products were determined by alpha spectrometry and total alpha measurement system after elapsed time of 15 days from precipitation. ma...

Abstract The JRC applied six measurement techniques to standardise the activity of an 241 Am solution in frame 2003 key comparison CCRI(II)-K2.Am-241. methods used were alpha-particle counting at a defined small solid angle, high-efficiency particle and photon with windowless 4π CsI(Tl) sandwich spectrometer, alpha pressurised proportional counter, alpha-gamma coincidence sum counter NaI(Tl) we...

Introduction: After the lead poisoning outbreak came to light in Zamfara State, Nigeria, people living near gold mines were worried about environmental safety, especially drinking water quality. This study examined the gross alpha and gross beta activity concentrations in groundwater in different locations of Anka, Zamfara State, Nigeria, to measure the possible radiation dose and potential hea...

This paper describes main aspects related to determination of total alpha and beta in drinking water samples. A short description of the procedure is presented, emphasizing possible sources of uncertainty. A Gas Proportional Counter from Canberra Tennelec Series 5 Extra Low Background (S5XLB) equipped with a sample changer was employed for sample counting. Proper alpha self absorption correctio...

Purification of alpha-amylase from the cultivation supernatant of recombinant Bacillus subtilis by high-speed counter-current chromatography (HSCCC) in polyethylene glycol (PEG) 4000-inorganic salt aqueous polymer two-phase systems was studied. The effects of sodium chloride concentration on the partition coefficients of alpha-amylase and total protein were respectively tested in PEG4000-phosph...

We consider accretion disks consisting of counter-rotating gaseous components with an intervening shear layer. Configurations of this type may arise from the accretion of newly supplied counter-rotating gas onto an existing co-rotating gas disk. For simplicity we consider the case where the gas well above the disk midplane is rotating with angular rate +Ω and that well below has the same proper...