ABSTRACTBackground: An electron beam generated X-ray spectrum consists of characteristic X-ray and continuous bermsstrahlung. The aim of this research is calculating and comparing X-ray spectra for different target filter of mammograms. Materials and Methods: Monte Carlo is a very powerful tool to simulate a series of different target-filter assembly in order to calculate the X-ray spectra. MC...

second order advantage of excitation-emission fluorescence matrix was applied for the simultaneous determination of ibuprofen and caffeine. the proposed method is based on the measurement of the native fluorescence and recording emission spectra of ibuprofen and caffeine in different excitation wavelengths. the mixture of these compounds was resolved by multivariate curve resolution coupled wit...

in this work facile sol-gel (pechni) method has been successfully established to synthesize zn4b6o13 nanocrystals which have cubic crystals with lattice parameter: a =7.48 a. the structure and morphology of the obtained material were studied by x-ray diffraction (xrd), infrared spectra (ir), scanning electron microscopy (sem) and photoluminescence analysis. the experimental results show a band ...

a spectrophotometric study concerning the interactoin between iodine and bromine with tetrabutylammonium iodide (tbai), tetrabutyl- ammonium bromide (tbabr) and cryptand 222 (c222) has been performed in dichloromethane solution at 25°c. the results are indicative of the formation of tba+x3- and  c222x+x3-  through equilibrium and formation of c222x+x-  through nonequilibrium reactions. the stab...

the aim of this research was to identify the life form spectra in the irano-tourani region. identifying these spectra can reveal the relevant life form species. by comparison these spectra with other regions, life form spectra, the situation of this region among the other regions can be determined. it was carried out using raunkiaer’s method to determine the life form spectra from irano-tourani...

A spectrophotometric study concerning the interactoin between iodine and bromine with tetrabutylammonium iodide (TBAI), tetrabutyl- ammonium bromide (TBABr) and cryptand 222 (C222) has been performed in dichloromethane solution at 25°C. The results are indicative of the formation of TBA+X3- and  C222X+X3-  t...

ftr-raman spectra of human dental enamel, both laser-irradiated and untreated, are reported. spectra are compared with hydroxyapatite. it is evident that unlike the co2 laser, the nd/yag laser does not induce any chemical change in dental enamel.

We review and extend the theory of Thom spectra and the associated obstruction theory for orientations. Specifically, we show that for an E∞ ring spectrum A, the classical construction of gl1A, the spectrum of units, is the right adjoint of the functor Σ∞+ Ω ∞ : ho(connective spectra) → ho(E∞ ring spectra). To a map of spectra f : b → bgl1A, we associate an E∞ A-algebra Thom spectrum Mf , which...