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- Author or Editor: M. Ramadan x
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Abstract
Let G be a finite group. A PT-group is a group G whose subnormal subgroups are all permutable in G. A PST-group is a group G whose subnormal subgroups are all S-permutable in G. We say that G is a PTo-group (respectively, a PSTo-group) if its Frattini quotient group G/Φ(G) is a PT-group (respectively, a PST-group). In this paper, we determine the structure of minimal non-PTo-groups and minimal non-PSTo-groups.
Abstract
Chemical factors such as pH, concentration and temperature affecting the removal of UO2 2+, Th4+, Fe3+, Cu2+, Pb2+,Cd2+, Ni2+, MnO4 - and phenol by Eichornia crassipes aquatic plant from their solutions were examined. Maximum uptake of ions by Eichornia crassipes occurred at pH 4 to 6±0.5 at 25±3 °C. An initial rapid uptake phase for the first 6 hours followed by a slower near linear one was observed. One gram of Eichornia crassipes can accumulate about 25 mg UO2 2+, 5 mg Th4+, 30 mg Fe3+, 10 mg MnO4 -, 15 mg Cu2+, 1.0 mg Pb2+, 1.5 mg Ni2+, 0.7 mg Cd2+ and or 25 mg of phenol.
Abstract
We study the structure of a finite group G under the assumption that certain subgroups lie in the generalized hypercenter of G.
Abstract
Let G be a finite group. For a finite p-group P the subgroup generated by all elements of order p is denoted by Ω1(p). Zhang [5] proved that if P is a Sylow p-subgroup of G, Ω1(P) ≦ Z(P) and N G (Z(P)) has a normal p-complement, then G has a normal p-complement. The object of this paper is to generalize this result.
Abstract
A stone of brick-like shape, measuring roughly 25×12.5×10.5 cm3 and weighing 14 kg was found in 1983, in the western desert of Egypt. The meteorite was named El-Bahrain meteorite and classified as L-chondrite. In the present paper, the principal constituents of El-Bahrain meteorite have been studied by means of Mössbauer spectroscopy. The chemical composition as obtained by the conventional wet analyses of L-chondritic meteorites showed that the meteorite contains 23.38% Fe and 1.23% Ni. While the analysis of the atomic absorption showed the presence of 27.03% as a total iron. The Mössbauer analysis of El-Bahrain meteorite showed that the iron constituent minerals were determined to be olivine, metallic iron-nickel alloys (kamacite, taenite and tetrataenite), ferrous sulfide (troilite) and weathering products such as maghemite and nanocrystalline hematite. The structure of meteoritic iron obtained by the Mössbauer analysis has been discussed on the basis of these constituents.
Abstract
The extraction of Eu(III) by dinonylnaphthalenesulfonic acid (HDNNS) in benzene from nitrate and perchlorate solutions has been investigated. For nitrate solutions the ionic strength of the aqueous phase was kept constant at 0.1M using NaNO3–HNO3 mixtures. The Eu distribution was measured at different temperatures. The following stoichiometric formulae for the Eu species in benzene were derived: Eu(NO3) (Hn–1 (DNNS)n)2 and Eu(Hn–1 (DNNS)n)3, from the nitrate and perchlorate medium respectively (n being a small number, e.g. 1, 2 or 3). The equilibrium constants were calculated and the thermodynamic parameters of the system were determined. When adding dibenzo-24-crown-8, dicyclohexyl-18-crown-6 or trioctylphosphine oxide, no synergism, but rather antagonism was observed.
Abstract
The mechanism of the decomposition of the entitled compounds and their complexes is studied. Adenine, its Schiff base of salicylaldehyde, and its azo resorcinol derivatives are ended with carbon. However, oxalonitrile compound is appeared as a final product for adenine acetylacetone and an intermediate for adenine. The thermodynamic parameters of the decomposition reaction were evaluated and discussed. The change of entropy values, ΔS #, showed that the transition states are more ordered than the reacting complexes. The thermal processes proceed in complicated mechanisms where the bond between the central metal ion and the ligands dissociates after losing small molecules such as H2O, NH3, or HCl. In most cases, the free radical species of the ligands are assigned to exist through decomposition mechanisms. The copper adenine and nickel salicylaldehyde complexes are ended with the metal as a final product. However, the cobalt adenine, its acetylacetone, its salicylaldehyde, cadmium and mercury guanine complexes are ended with metal oxides.
The main objective of this work was to evaluate the composition, nutritional, physical and rheological properties of wheat flour and dough from genetically modified wheat (Triticum aestivum L.) Hi-Line 111 (GMW) compared to conventional wheat (non-GMW). Analyses were conducted to measure the proximate chemical composition with references to 18 components including total solid, protein, lipids, crude fiber, ash, carbohydrate, minerals, amino acids, and fatty acids. In addition, physical and rheological properties such as water absorption, arrival time, dough development time, stability value, dough weakening value, extensibility of dough, resistance to extension, and ratio of resistance/extensibility were evaluated. The results showed that there were no significant differences between GMW and non-GMW in terms of chemical composition. Results revealed the presence of saturated and unsaturated fatty acids wherein there were no significant differences between GMW and its counterpart in the levels of fatty acids. In addition, there were no significant differences on the levels of amino acids. In addition, there were no significant differences between the GMW and non-GMW in the physical and rheological properties. From these results, it can be concluded that GMW Hi-Line 111 is confirmed to have nearly the composition and rheological properties as non-GMW.
The laelapid mites Cosmolaelaps keni and Laelaspis astronomicus beside the rhodacarid mite Protogamasellopsis denticus are biological control agents and being native predators in Egypt. In order to raise active population of above species, the biology and demographic parameters, of the three tested species were observed under laboratory conditions with eggs of Ephestia kuhniella. All predatory species were developed and reproduced with E. kuhniella eggs. The mean developmental and oviposistion periods of L. astronomicus females were the longest from the other tested species. The mean longevity of C. keni was longer than that of P. denticus. Cosmolaelaps keni consumed more E. kuhniella eggs during the oviposition and adult longevity periods than other species did. Protogamasellopsis denticus fed on E. kuhniella food gave the most rate of oviposition as shown by the maximum fertility, net reproductive rate and gross reproductive rate. Laelaspis astronomicus preying on E. kuhniella eggs gave the longest generation time, lowest rate of fecundity and all life table parameters compared to other tested species; therefore E. kuhniella eggs was appropriate for the oviposition of P. denticus and C. keni rather than L. astronomicus.
This study is the first to report that E. kuhniella eggs were an acceptable factitious food for P. denticus, L. astronomicus and C. keni.
