Vol. 7 Issue 3
Amar H. Al-Dujaili, Aubrey D. Jenkins and David R. M. Walton
The development of the polymer structure, during the polymerization process, was found to play an important role in the formation of the liquid-crystalline structure. The polymer prepared from chiral (+)-3- methyl adipoyl chloride displays a typical cholesteric mesophase texture. Liquid-crystalline properties and phase-transition temperatures were found to be affected less or more by the chemical constitution of the mesogens.
El Sayed A.A. Youssef
The fabrics and presence of celestite in the carbonate cements in the reefal limestone of Gebel El Rusas Formation and the sabkha sequences of the Abu Dabbab Formation (Middle Miocene) suggest deposition in a hypersaline vadose regime. The recorded carbonate cements are represented by paleo flowstone crusts; spheroidal and hemispheroidal structures and giant paleo aragonite ray- crystals deposited in fenestrae and as crusts within the Miocene sediments.
The carbonate cements occur in the form of polycrystalline calcite pseudo spar and fibrous calcite resulting formed as paramorphic replacements of aragonite in a Mg poor fresh water vadose regime. Traces of native sulfur occur together with secondary gypsum and calcite in the suricial layer of the Abu Dabbab evaporites. The sulfur is formed in a localised microenvironment in the fresh water vadose regime and is a response to bacterial activity on sulfate deposits.
Fahmy M. Hussein, K. El-Malahy, H. Sofrata and M.A. Obeid
The fuzzy decision analysis technique is used for priority determination of the best location for a dual purpose nuclear power plant on the west coast of the Arabian Peninsula. From among several suggested locations, only four were chosen for further evaluation since they met specific minimal criteria and international standards. Two of the four sites are located on the northern part of the Red Sea Coast and the other two on the southern part. Twenty criteria were used in the analysis.
The analysis ranked the fourth site in first place followed by the third one.
Ezzat T.M. Selim, M.A. Rabbih, M.A. Fahmey Ahmad and Ahmed S. Shalbi
The different processes for formation of [C5H3]+ fragment ion, for a range of 3 eV above threshold, from benzyl alcohol, benzylamine and benzyl cyanide have been suggested and discussed. Appearance energies for the ion have been measured using electron impact technique. The results indicate, that at threshold as well as at higher energies, the [C5H3]+ ion generated from the three precursors is a linear ion. A MNDO SCF method is used to calculate the heats of formation for the linear and cyclic structures of the ion. The substituent effect of -OH, -NH2 and -CN groups on the activation energy as well as excess energy term is also discussed
A.Q. Siddiqui, M. Shahjahan Howlader and A. El Badawy Adam
Date palm leaf silage was used as an alternative fish feed, and was fed to Oreochromis niloticus of two weight groups. The growth rates and food conversion ratios were compared with fishes of similar weight groups but fed on commercial fish feed; other treatments being the same. The growth performance and feed utilization was less efficient for the silage and this difference was more apparent for smaller weight fishes (mean weight 9.1 g) than for larger fishes (mean weight 125.0 g). Although the water quality with respect to dissolved oxygen content, pH and ammonia levels were not affected, yet considerable amount of fiber accumulated in tanks receiving silage and it required considerable efforts to flush it off. The date palm lead silages appears to be suitable for larger fishes but suitable for small size fishes in tank culture system. However, it could be used as a supplemental feed in pond culture systems where dependence is on natural food.
A.A. Alsobayel, F.M. Attia and M.S. Bayoumi
Growth, feed intake, feed to gain ratio, and abdominal fat was evaluated in Hubbard and Shaver broilers subjected to early feed restriction using a complete practical diet. The design consisted of 3 feeding regimens: the ad libitum feeding (C), medium restriction (MR), and severe restriction (SR). Feed restriction was imposed during the second and third weeks of age and was followed by ad libitum feeding to the age of 7 to 8 weeks.
In all restricted fed birds, weight gain during the refeeding period was sufficiently high to compensate fully for growth retardation during the restriction period. Final body weights of restricted-fed birds were not statistically different from their ad libitum-fed controls. These data demonstrate that the broiler chicken has the ability for compensatory growth when ad libitum feeding follows early feed restriction. Total feed intake was significantly reduced with the increase in feed restriction. No significant differences were found between the two broiler strains for all parameters studied.
Females had significantly higher abdominal fat percentages over the males for both strains of birds. However, these sex differences within each age period were statistically indistinguishable. An overview of these results suggests that early feed restriction has no deleterious effect upon final body weights at 7 or 8 weeks of age.
M.A. Clor, T.A. Al-Ani, and F.M.R Al-Charchafchi
Seeds of Haloxylon salicornicum consist of an embryo axis which forms a compressed spirillum, and the young seedlings show a variety of irregular shapes. Germination is viviparous in nature and can take place any time after maturation if enough moisture is available. After heavy rains in November and December, germinating seeds are often observed on intact fruits still attached to the bush. Highly viable seeds, hydrated for several hours and redried for a week, maintained full germination capacity and produced normal seedlings upon rehydration. Very young seedlings survived drying for a week and became reactivated upon hydration.
Abdel-Aziz Fayed and Kamal Zayed
This is a survey of the plant growth of Makkah-Taif road (Saudi Arabia) that covers a distance of about 100 km, with a sharp rise from 300 to 1500 m above sea level. 109 species of vascular plants, belonging to 36 families, are recorded. Twenty two plant communities are recognized, two of which dominated by ephemerals. Relations between communities and their habitat types are briefly discussed.
A.S. Khaliel, A.N. Abou-Heilah and M.Y. Kassim
Fruiting bodies of the edible mushroom Podaxis pistillaris, growing in the wild in various regions of Saudi Arabia, were collected to determine their nutritive value for human consumption. The main chemical constituents determined were moisture content (76%), total nitrogen (5.0%), total crude protein (N X 6.25) averaged (22-37%), total protein (34.9%), total carbohydrates (18.5%), total lipids (2.3%), and ash content (12.4%). The quantities of desirable (K, Na, Fe, Mg, Mn, Ca, and Zn) and undesirable minerals (Pb and Cd) were determined. Seventeen amino acids were also determined. These constituents are discussed in terms of the importance of P. pistillaris as a source of nutrients for human consumption.
Ziad Shraideh and Fawwaz Al Khalili
The effect of different concentrations of dichloroglyoxime (DCG) and dimethylglyoxime (DMG) on the cytoplasmic shuttle streaming (in vivo) and on the contraction-relaxation activity of excised plasmodial strands (in situ) were investigated. In the concentration range between 0.5- 2 µg/ml, DCG caused disturbances and subsequent stop of cytoplasmic streaming. Higher concentrations induced a direct and rapid stop of cytoplasmic streaming followed by contraction of the whole plasmodium, blebbing and disintegration of plasma membrane. These effects were completely irreversible. Concentrations of DCG ≤ 0.5 µg/ml induced concentration of excised plasmodial strands measured tensiometrically under isometric conditions. A concentration dependent decrease in frequency of the contraction-relaxation cycle, but an increase in force amplitude were observed. A concentrations of DCG ≥ 2.0 µg/ml caused a single, very strong contraction followed by an irreversible relaxation. DMG did not induce obvious effects on migrating plasmodium or cytoplasmic streaming. When applied to isometrically oscillating excised strands of Physarum, DMG showed a concentration-dependent decrease in oscillation frequency. These results showed that some glyoxime derivatives (even in micromolar concentrations) have cytotoxic effects. Further investigations should be done before recommending such derivatives as commercial disinfectants.