Results 281 to 290 of about 791,939 (337)

The effective atomic number of dosimetric gels

Australasian Physics & Engineering Sciences in Medicine, 2008
Radiological properties of gel dosimeters and phantom materials are often compared against each other and against water or tissue by consideration parameters including their effective atomic number, Zeff. Effective atomic numbers have been calculated for a range of ferrous-sulphate and polymeric gel dosimeters using mass attenuation coefficient data ...
Taylor, M, Franich, Rick, Trapp, Jamie, Johnston, Peter   +3 more
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X-ray energies for effective atomic number determination

Neuroradiology, 1976
The measurement of the effective atomic number of a piece of material in vivo can be achieved using computed tomography. The precision of measurement of this parameter depends on the precision of measurement of the X-ray absorption coefficient at two energies and the separation of these energies.
R A, Rutherford, B R, Pullan, I, Isherwood   +2 more
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Determination of atomic cross-sections and effective atomic numbers for some alloys

Annals of Nuclear Energy, 2000
Abstract The transmission of gamma-rays at the energies, 81, 356, 511, 662, 835, 1274 and 1332 keV has been studied on the alloys brass, bronze, steel, aluminum–silicon and lead–antimony. The mass absorption coefficients have been measured. The total interaction cross-sections and effective atomic numbers have been determined on the basis of mixture ...
A.H. El-Kateb, R.A.M. Rizk, A.M. Abdul-Kader   +2 more
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An Experimental Evaluation of the Atomic Number Effect

Advances in X-ray Analysis, 1973
AbstractA method for measuring the atomic number effect is developed using a sandwich sample technique. The depth distributions of x-ray production, ϕ(ρz) curves, have been measured for a zinc tracer in aluminum, copper, silver and gold matrices at 30, 25, 20 and 15 keV. The ϕ(ρz) curves were measured using a Cambridge Microscan 5 in which the electron
L. Parobek, J. D. Brown
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Effective principal quantum numbers of valence atomic orbitals

Chemical Physics Letters, 1971
Abstract Analysis of radial moments of Hartree-Fock atomic orbitals shows that their shape near the radial maximum implies an effective principal quantum number that remains small even for heavier elements.
L.C. Cusachs, H.S. Aldrich
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Effective atomic numbers for materials of dosimetric interest

Radiation Physics and Chemistry, 1997
Abstract Effective atomic numbers ( Z eff ) for different materials of dosimetric interest have been calculated for total photon interaction in the energy region 1 keV–20 MeV. The calculations are made using the mass attenuation coefficients data from Tables of X-ray Mass Attenuation Coefficients and Mass Energy-absorption Coefficients 1 keV to ...
T.Kiran Kumar, K.Venkata Reddy
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Effective Atomic Weight, Effective Atomic Numbers and Effective Electron Densities of Hydride and Borohydride Metals for Fusion Reactor Shielding

Journal of Fusion Energy, 2014
The effective atomic weight, A eff , mass attenuation coefficients, μ/ρ, half-value layer, HVL, effective atomic numbers, Z eff and effective electron densities, N eff of hydride and borohydirde metals,
Vishwanath P. Singh, N. M. Badiger
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Effective Atomic Numbers of Heterogeneous Materials

Nature, 1965
FOR a single element, the three γ-ray processes—photoelectric, Compton and pair production, can be expressed as a function of photon energy hν and the atomic number Z of the element. At a given photon energy, the interaction is proportional to Zn where n is between 4 and 5 for the photoelectric effect, 1 for the Compton effect, and 2 for pair ...
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Effective atomic numbers of alloys from bremsstrahlung measurements

Il Nuovo Cimento B, 1977
The effective atomic numbers of three alloys Cu-Ag, Cu-Sn and Sn-Pb were determined by measuring the external-bremsstrahlung (EB) total yields produced in those alloys and also in the constituent elements due to the stoppage in them of the continuous beta-radiation from32P,45Ca,169Er and185W.
V. V. V. Subrahmanyam, K. Narasimha Murthy, D. G. S. Narayana   +2 more
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Mass attenuation coefficients, effective atomic numbers and effective electron densities for some polymers

Radiation Protection Dosimetry, 2012
In this study, the total mass attenuation coefficients (μ(m)) for some homo- and hetero-chain polymers, namely polyamide-6 (PA-6), poly-methyl methacrylate (PMMA), low-density polyethylene (LDPE), polypropylene (PP) and polystyrene (PS) were measured at 59.5, 511, 661.6, 1173.2, 1274.5 and 1332.5 keV photon energies.
Küçük, Nil, Isitman, Nihat Ali, Cakir, Merve   +2 more
openaire   +3 more sources