Vol. 5 Issue 1
Ali A. Fora and Mahmoud H. Al-Refa'ei
The relation between any bitopological space and its least upper bound topology is studied. A new type of pairwise continuous functions between bitopological spaces is presented as well. Then, we use the concept of pairwise continuous functions to introduce the concept of pairwise fixed-point property, pairwise retraction functions and pairwise contraction functions between bitopological spaces. We also obtain some generalizations of some well-known results concerning fixed point theory for a single topological space.
C.M. Ashraf
The mass spectra of substituted 1,3-dimethylindan-I-ols (R=H, NH2, Cl) have been recorded under similar conditions, and mechanistic schemes proposed to explain their fragmentation. It has been observed that the substituents have little effect on the mode of fragmentation, other than expected. Some of the proposed cleavages have been substantiated by appropriate metastable peaks, while the mass spectra of some related compounds support the generation of some other observed ions.
O. Zahraa, S.H. Al Khowaiter, and E. Ammar
The kinetics of cyclohexene hydrogenation over Pt-AI2O3 catalysts was investigated in a static reactor, between 303 and 373k. and hydrogen partial pressure from 40 to 220 torr, and cyclohexene partial pressure from 20 10 80 torr. Cyclohexane was the only product observed. The rate of hydrogenation (torr min -1 g Pt -1) exhibited a maximum at 160 torr of hydrogen. The reaction order with respect 10 hydrocarbon has been found slightly negative at low temperature, and about (0.5) at high temperature. The order with respect to hydrogen varied from (0.8) to (-1) as the pressure of hydrogen increased. The experimental results of this work implied that the hydrogenation on alumina-supported platinum proceeds via the associative mechanism.
Ezzeldine H. Ibrahim and Ibrahim S. Alnaimi
The methods of preparation and possible reaction mechanisms for the formation of cyclodiphosph (V) azanes, [MeP(S)NR]2, are discussed. There compounds and their monomeric precursors, MeP(S)(NHR)2, have been investigated using 1H, 13C, 31P spectrometry.
H. El-Didamony, M.G. Abd El Wahed, Kh. M. Elewa and A.A. Amer
Disposal or utilization of rice husk creates a problem for rice-growing countries. Its ash is whitish and fluffy that consists mainly of amorphous silica. This form is inert and not useful for agricultural and industrial purposes.
The result of this study presents the nature of fried rice husk ash. IR-spectroscopy and X-ray diffractometry technique were utilized. The reactivity of rice husk ash toward formation of beta-C2S was also investigated. The results showed that rice husk ash fired up 10 700"C is amorphous. whereas cristobalite is formed in increasing quantities at higher temperatures. The rate of formation of beta-C2S from rice husk ash is faster than from silica quartz, It may be concluded that rice husk ash is more reactive than natural quartz.
Mohamed E. Habib
Landsat-1 images. computer -enhanced displays and field criteria have shown that the post kinematic granites and related hydrothermal mineralization in the Pan-African basement of the Central Eastern Desert of Egypt were controlled by well-defined lineaments trending NNE-to-NE, NW, WNW, N and ENE-to-E. These lineaments proved to be surface expressions of major fractures. The NNE -to -NE and NW lineaments are particularly significant: they have guided the emplacement of large volumes of granitic magma and are metallotects for hydrothermal mineralization containing as Au. U. Cu. and W. Field evidence prove that the tectonism responsible for these lineaments was recurrent and alternated with the magmatic activity and hydrothermal mineralization. Preliminary investigations along the lineaments detected show indications of mineralization particularly in the vicinities of intersections.
H. Khalifa
Eighteen species of calcareous algae belonging to the families Corallinaceae, Dasycladaceae and Codiaceae are recorded, for the first time, from the Middle Eocene rock succession at Gabal El Mereir and Gabal Teir. Nile Valley. Egypt.
The corallines comprise two species of Archaeolithithamnium two species of Mesophyllum. one species of Lithophyllum. one species of Lithoporella and one species of Jania. Ten species of Dasycladacean algae are represented by the following nine genera: Diplopora, Actinoporella, Cymopolia, Neomeris, Larvaria, Trinocladus, Thyrsoporella, Belzungia. Furcoporella, and one species of Ovulites belongs to the Family Codiaceae. One new Dasycladacean species, Dipolopora aegyptiaea, is described.
On the basis of these algal assemblages, the sections studies are referred to the Middle Eocene.
Ahmed Riad Ibrahim
The methods of mathematical modelling for the filtration properties of the rocks are discussed. The relation between the porosity of a rock and its clearance in under formed state, and under external loads is derived. The coefficient of volumetric filtration are expressed mathematically in two different cases; assuming the shape of the pores either cylindrical or slot shaped channels. The paper contains (37) mathematical formulae and three figures which illustrate various relationships between the studied parameters.
Salim S. Al-Showiman
Carbon-13 chemical shift assignments are reported for some N-tertbutylimines bearing ortho-substituted C-phenyl rings. The influence of electronic and stereochemical effects on the l3C signal positions were inspected. The variation of the 13C chemical shifts allows calculation of the substituent chemical shift (SCS) effects. The results indicate that electron withdrawing substituents cause up field shifts in the position of the C=N resonance.
Ibrahim N. Al-Nasser and Mostafa S. Afifi
A multibeam satellite reflector antenna to provide contiguous multibeam coverage of Saudi Arabia is analized. The satellite utilizes 12 beams each of 10 cell size. Three overlapping beams were formed, which comply with the ITU requirements. Composite coverage patterns are computed, projected on a map.