Auger Spectra and Different Ionic Charges Following 3s, 3p and 3d Sub-Shells Photoionization of Kr Atoms

The decay of inner-shell vacancy in an atom through radiative and non-radiative transitions leads to final charged ions. The de-excitation decay of 3s, 3p and 3d vacancies in Kr atoms are calculated using Monte-Carlo simulation method. The vacancy cascade pathway resulted from the de-excitation decay of deep core hole in 3s subshell in Kr atoms is discussed. The generation of spectator vacancies during the vacancy cascade development gives rise to Auger satellite spectra. The last transitions of the de-excitation decay of 3s, 3p and 3d holes lead to specific charged ions. Dirac-Fock-Slater wave functions are adapted to calculate radiative and non-radiative transition probabilities. The intensity of Kr^{4+} ions are high for 3s hole state, whereas Kr^{3+} and Kr^{2+} ions have highest intensities for 3p and 3d hole states, respectively. The present results of ion charge state distributions agree well with the experimental data.Comment: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA

Past I: a petrological study op the prinsen af wales bjaerge lavas, East Greenland II: the two granphyres of meall dears, skye, with a special study of the clinopyroxene contained in one of them

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Antifungal activity of rice straw extract on some phytopathogenic fungi

The antifungal activity of allelochemicals extracted from rice straw on the radial growth rate and the activity of some hydrolyzing enzymes of Aspergillus flavus, Alternaria alternata and Botrytis cinerea were studied in vitro. Five different concentrations (2, 4, 6, 8 and 10%, w/v) of water, methanol and acetone extracts of rice straw were tested. All extracts significantly (P<0.05) inhibited the radial growth rate and protease, carboxymethyl cellulase (CMCase) and amylase activities of the tested fungal species. The most potent solvent was methanol. The present study suggests that rice straw extract had antifungal properties, thus it can be used as a natural alternative approach to synthetic fungicide.Key words: Rice straw, allelochemicals, antifungal, Aspergillus flavus, Alternaria alternata, Botrytis cinerea, amylase, protease, carboxymethyl cellulase

Bioaccumulation of heavy metals in water, sediment and fish (Oreochromis niloticus and Clarias anguillaris), in Rosetta branch of the River Nile, Egypt

Rosetta Branch of the River Nile is exposed to high input of agricultural drainage water, sewage and industrial water that affect living organisms like fish. In the present study, some heavy metals such as iron, copper, lead, cadmium and zinc (Fe, Cu, Pb, Cd and Zn) were seasonally determined in some tissues of tilapia (Oreochromis niloticus) and catfish (Clarias anguillaris), water sediment and in Rosetta branch of River Nile at the following areas: El-Kanater El-Khairya (I), El-Rahawy drain (II), Tamaly (III) and Kafer El-Zyate (IV), which are an important water source for irrigation and drinking in Egypt. The highest levels of heavy metal accumulated in the liver of C. anguillaris were Fe, Cu, Pb, Cd and Zn than accumulated in O. niloticus. In gills of C. anguillaris, the highest accumulation of metal levels were Zn, Fe, Pb, Cd and Cu than accumulation in gills of O. niloticus. In muscles of C. anguillaris, the highest accumulation of metal levels were recorded for Fe, Zn, Cd and Cu except Pb was highest in O. niloticus muscles. Bioaccumulation factor (BAF) of all heavy metals in organs of C. anguillaris was higher than O. niloticus. Heavy metal levels in water, sediment and fish samples were analyzed by using atomic absorption. The order of heavy metal accumulation in water was Fe > Pb > Cu > Zn > Cd. Maximum metal index (MI) recorded at station IV for Fe, Cu, Pb and Zn were 2.7, 0.3, 62 and 0.17 mg/L, respectively and Cd was 15.333 mg/L at station III. The order of heavy metal accumulation in sediment was Fe > Zn > Cu > Pb > Cd. It was discovered in the present study that fish can bioaccumulate heavy metals from a polluted environment and could be a risk factor for accumulation of heavy metal in humans after a long time that would lead to dangerous diseases.Keywords: Heavy metals, metal index (MI), bioaccumulation factor (BAF), Oreochromis niloticus, Clarias anguillaris, gills, liver, muscle

Numerical simulation of the flow about an F-18 aircraft in the high-alpha regime

The current research is aimed at developing and extending numerical methods to accurately predict the high Reynolds number flow about the NASA F-18 HARV at large angles of attack. The resulting codes are validated by comparison of the numerical results with in-flight aerodynamic measurements and flow visualization obtained on the HARV. Further, computations have been used to provide an analysis and numerical optimization of a pneumatic slot blowing concept, and a mechanical strake concept, for use as potential forebody flow control devices in improving high-alpha maneuverability