Earlier investigations of the inuence of geomagnetic activity on radio wave absorption were based on storm selection criterion: SKp ³ 30. This criterion lumped together weak, moderate, and strong storms, and favouring weak and moderate storms made it impossible for the investigations to detect any change in equatorial radio wave absorption following geomagnetic storms. Presently, the effect of geomagnetic storms on equatorial radio wave absorption has been investigated using severe storms (Ap ? 54) and HF absorption data obtained at 4.87 MHz at 1000 hours LT at Lagos (3. 40oE, 6. 55oN). The absorption data were measured using radio waves reected from the F region, and the transmitter (Radio Cotonou) is located at Cotonou (2.43oE, 6.35oN). The present results obtained using the superposed epoch method show that HF absorption in the equatorial ionosphere increases after severe geomagnetic activity.
A preliminary pulse radiolytic study is reported on transient optical absorption spectra in solid amino acids. Spectra have been obtained by improved Cherenkov Light Self-absorption Method applied during 5.5 s pulses of 10 or 13 MeV linac electrons. Amino acids exhibit a very different type of behaviour: from lack of absorption signal (at the present sensitivity of the system) to strong absorptions in the visible part of the spectrum and the near UV. The absorption may be due to the electron trapped in lattice imperfections or to the formed free radical. Comparison of spectra in a variety of preparations (hydrochlorides, salts of amino acids and sets of related compounds) suggests a free radical origin of spectra. All transient absorption disappear within a fraction of a second. Free radicals turn by deamination and/or decarboxylation into more stable species detected by ESR.
As part of an extended study of the absorption of uranium in life structures,some experiments on the uranium absorption in cultures of Saccharomices cerevisiaewere carried out. Using the wet ashing Arsenazo III method the absorbed weightof uranium in dregs dry cells was determined.
Authors:Mariann Harangi, István Balogh, János Harangi, and György Paragh
Santosa, S., Varady, K. A., AbuMweis, S. és mtsa:
Physiological and therapeutic factors affecting cholesterol metabolism: does a reciprocal relationship between cholesterol absorption and synthesis really exist? Life Sci., 2007,
Authors:Rózsa Sándor, Hargitai Rita, Láng András, Hartung István, Martin László, Tamás István, Tiringer István, and Kállai János
Exploration of Bodily Self-Awareness . Oxford : Oxford University Press . Duplin , B ., & Heller , G . ( 2010 ). Going to other worlds: The relationships between, video gaming, psychological absorption, and daydreaming style . Cyberpsychology
A statistical interpretation of the transmission vs. thickness curves indicates that the traditional mass absorption coefficient consists of two terms: one is the mass attenuation coefficient (MAC), the second depends on the central moments of the MAC. A theory of the mass attenuation coefficient is proposed. The theoretical results are in agreement with experiments. Comments on the shell effect have been presented.
We have investigated the effects of scattering and absorption in neutron beam activation analysis experiments, both by direct measurement and by Monte Carlo simulation. Significant sensitivity enhancements occur for thin disks placed at 45° to the beam but very much smaller effects occur for spheres. The agreement between measurement and calculation is generally good.