ct.scan examinations cause high patient absorbed dose from x-ray ionizing radiation. therefore it is necessary to obtain superficial dose profile in z-line. in this research 11 thermoluminecent dosimeter (tld), after calibration were located on z line perpendicular to slice thickness. ct.scan machines did x-ray exposures. the resultant dose profiles showed gussian shape apperience, which has se...

background: a study has been conducted to assess two useful radiation protection indices, the annual per-capita effective dose equivalent (aed) and the genetically significant dose (gsd), from conventional diagnostic radiography in 10 counties with more than 1,886,000 inhabitants in khorasan province in iran. materials and methods: the health centre authorities of khorasan province were asked t...

background: radiation dose knowledge through xray examinations and their distribution in iran provides useful guidance on patient dose reduction. the results of the entrance skin dose (esds) of five common radiographies in all radiology centers in yazd province were reported in our previous study (2003). in the present study we have evaluated the collective effective dose of conventional x-ray ...

background: with the introduction of computed tomography in diagnostic radiology a new and fundamentally different imaging modality has become available. meanwhile, it is clear that the absorbed doses by the patients during ct were relatively high in comparison with those of other diagnostic radiology techniques. the aim of this survey was to determine the average absorbed dose in yazd province...

background: for an effective treatment planning in brachytherapy, it is necessary to know the accurate source dosimetric information such as air kerma strength, exposure rate constant, dose rate constant and redial dose distribution. the usual method to determine these factors is thermo luminescent dosimeter (tld) dosimetry. nowadays, another more accurate method is known to be the monte carlo ...

The presence of humic acid (HA) in water treatment processes is very harmful and the cause of undesirable color, taste, and smell. Drinking water containing high concentrations of humic substances can be the cause of many health problems. Therefore, the removal of these compounds from water resources is a very important topic. In this research, response surface methodology (RSM) has been used t...

Abstract A data-based multivariate method such as response surface methods and desirability function is considered advantageous for analysing coagulation treatment optimization. Thus, this study investigated the optimization of coagulation–flocculation using methodology. The parameters were pH, alum dose alkalinity. optimum conditions individual responses: turbidity, colour, residual aluminium ...

Summary In this article we further develop field theory [6], [7], [12] in Mizar [1], [2], [3]: deal with quadratic polynomials and extensions [5], [4]. First introduce polynomials, their discriminants prove the midnight formula. Then show that - case discriminant of p being non square adjoining a root ’s results splitting . Finally these are only degree 2, e.g. an extension E F is if there Elem...

Let D = 1 be a positive non-square integer and let δ = √ D or 1+ √ D 2 be a real quadratic irrational with trace t = δ + δ and norm n = δδ. Let γ = P+δ Q be a quadratic irrational for positive integers P and Q. Given a quadratic irrational γ, there exist a quadratic ideal Iγ = [Q, δ + P ] and an indefinite quadratic form Fγ(x, y) = Q(x−γy)(x−γy) of discriminant Δ = t − 4n. In the first section,...