Theoretical and experimental results have shown that109Cd X-rays are suitable for radioanalytical determinations of ash content in moistened coal. Errors due to variation of moisture are practically equal to zero, while those connected with the variations in iron and carbon content are acceptable.
The influence of iron on ash content determination on radiometric ways has been investigated. Principles of different methods of diminishing errors caused by variation in iron content have been demonstrated and discussed. The effectiveness of intrinsic iron compensation has been checked by coal samples of different chemical and mineralogical composition. It has been shown that the compensation of variations in iron content, is lim ed.
A closed analytical formula of the backscattering coefficient is described, in which the scattering function is calculated
with regard to the electron configuration and chemical bond of the target. The theoretical evaluations of the backscattering
coefficient have been compared with available experimental data and good agreement has been found.
A new method for the determination of ash content of coal with variable iron or lead concentration was developed. The method is based on the measurements of the backscattered or transmitted 22.0 keV energy X-rays and the90Sr+90Y backscattered -particles. The potentials and limitations of the method are illustrated in applications to coals from different mines and various chemical compositions of the mineral matter fraction.
A new method of sulphur content determinations in hard coal is presented. The method is based on the measurements of backscatterd X-rays and -particles. The method is suitable for analysis of Polish coal of various chemical composition, finely pulverized and of grain size 0–30 mm.
A closed analytical formula to calculate MAbCs regarding the effects of the atomic electron configuration in free and bound atoms has been derived. Theoretical results were compared with empirical data for 2.3 and 3 MeV -particles. The relative root mean square deviation of the theoretical predictions from the measured data does not exceed 7%.
An equation has been derived to describe the dependence of backscattered intensity on particle size in loose samples containing r-type of grains. The equation includes the density grain size effect and the grain size effect in compressed samples. The theoretical predictions are compared with experimental results.
An equation has been derived to describe the dependence of transmitted X-ray intensity on particle size in heterogeneous specimens
containing r-types of grains. The equation includes the effect of random distribution of grains in any volume element of the
sample, a problem not covered in earlier theoretical work.
New equations have been derived to describe the dependence of X-ray transmitted intensity on particle size in heterogeneous
specimens. The formulae include the effect of size distribution, a problem not covered in earlier theoretical work.