Vol. 5 Issue 3
Mohamed A. Gaffar and Abd El Aziz A.F. Abd El Aziz
The dielectric constant and both D.C. and A.C. electrical conductivity for pure and doped single crystals of TGS are investigated in the temperature range 300-450 °K. The influence of the divalent ions; Ni2+, Cu2+, and Co2+ and the trivalent ions; Cr3+, and Fe3+ on electrical conduction, transition behavior, transition temperature and dielectric properties in ferro- and paraelectric phases is studied. The difference between the effect of the two groups is more pronounced in the D.C. conduction. The A.C. technique is here proposed to give a clearer picture in the ferroelectric phase. A preliminary trial to study the effect of the pressure on the A.C. conductance is also mentioned.
M.A. Gaffar, M.M. Mebed, and A. Abu El-Fadl
The thermal diffusivity of pure and doped TGS crystals is measured from 30 to 80°C. The effect of heat treatment upon the thermal diffusivity of pure crystals exemplified the necessity of sample annealing before carrying out any measurements. The main features of the temperature dependence of thermal diffusivity in both ferroelectric and paraelectric phases are discussed. It is found that the valency and ionic radii of the dopant have a considerable effect on the obtained results.
H. Shadfan and A.A.A. Hussen
Nine soil profiles from Qassem and Hail regions of Central Saudi Arabia were investigated for their physical, chemical, and mineralogical properties. It was found that the soils of Qassem which were formed on Permain sediments were gypsiorthids, highly saline, and contained high amounts of kaolinite in the clay fraction. Soils formed on Quaternary deposits were Calciorthids with high carbonate in the topsoil. Palygorskite was found in high amounts in the clay fraction of these soils. Soils of Hail region which were formed from granite were Torriorthents with small amount of salts and carbonate. Smectite dominated the clay fraction of these soils. Soil properties of both regions were mainly determined by the parent materials of the soils. Most soils contained low amounts of nitrogen, available phosphorous, and zinc
Abd El Moneim M.R. Afify
Egyptian onion seeds (Giza 1 and Shandawel) were extracted with tris-borate buffer solution of pH 8.9. The protein buffer extract was examined by two dimensional electrophoresis (Mapping technique); with PAGIF in the first dimension, and Poro PAGE and SDS-PAGE in the second dimension. Differences between the cultivars, stored and fresh onion seeds could be detected.
Abdelmoneim I. Mustafa, Y.M. Makki, H.O. Burhan and O.A. Al-Tahir
Wheat (Triticum vulgare L.) cultivar Arz was grown under three levels of nitrogen fertilizer and four sowing dates between early November and late December of two growing seasons (82/83 and 83/84). The harvested grains were subjected to quality tests. Kernel weight increased with early sowing, but decreased with the increasing level of nitrogen fertilizer. The Pelshenke test results did not show any consistent effect of treatments but gluten and protein contents increased significantly with increase in fertilizer nitrogen level. The seed hardness test showed softness in the early November sowing, apparently due to rainfall in the first season during the late stages of maturity. This rain also caused black eye wheat and low maximum viscosity, which was detected by the amylograph, indicating minor sprouting and high diastatic activity. A decrease in the pasting temperature of the flour was noticed with an increase in nitrogen fertilizer level. High water absorption of the flour was noticed with the early sowing and higher nitrogen level. The dough developing time showed an increasing trend with increased nitrogen fertilizer, but no effect of sowing date was noticed on the dough development. The dough stability was generally low and inconsistent. Considering all quality parameters it seemed that this variety showed a reasonable response to the increase in nitrogen fertilizer indicating that its quality potential was almost reached under the hot arid conditions of the area. This wheat falls in the range of medium hard wheat. Early sowing improved the quality of wheat, provided that no late rains coincide with the harvest time.
E.H. Ewaidah
A study was designed to contrast the proximate, physical and elemental composition of 'Taifi' pomegranate fragments and to prepare jam from the edible portion (pulp and seeds) of the fruit. This cultivar is grown on a commercial level in the South-Western regions of Saudi Arabia. Proximate analysis indicated that moisture, protein, fiber and ash contents of the edible portion and juice of 'Taifi' pomegranates found in this study were in agreement with the literature values (FAO 1982, Paul and Southgate 1978). The edible portion of the fruit was rich in potassium and phosphorus, but poor in sodium, calcium, iron and magnesium. Optimum characteristics of 'Taifi' pomegranate jam resulted from formulations containing 3 parts edible portion and 2 parts sugar combined with citric acid and pectin at 0.20 and 1.24% (w/w) of the primary components, respectively. Sensory evaluation confirmed that jam manufactured from the edible portion (pulp and seeds) was highly acceptable with and without adding flavors. However, flavored products containing cinnamon, ginger, vanilla, cardamom and clove at concentration of 0.11%, 0.09%, 0.05%, 0.12% and 0.06% respectively were also very acceptable.
Mustafa D. K. Abo-Rady
Three soil profiles from different date palm orchards in Al-Hassa were described and sampled by horizons. Some chemical and physical properties of the samples were determined.
The three profiles were classified in the Entisol order of the Americal Taxonomy and are considered to be Orthents.
All of the profiles had light texture in the topsoil and heavier texture in the substratum. The soils were calcareous and had low contents of organic matter, available P and DTPA soluble Fe. The contents of Cu, Mn And Zn were higher than the critical levels below which deficiencies are to be expected.
Mohamed A. Mehaia
Isolated camel casein micelles were treated with pepsin, in both soluble and immobilized forms, to study the location and distribution of glycosylated portion (glyco-к-casein-like component) of camel casein micelle. The release of nonprotein nitrogen and sialic acid soluble in 2% and 12% trichloroacetic acid (TCA) was studied. Soluble pepsin released a maximum amount of 5.62 and 4.97 mg NPN/g casein soluble in 2% and in 12% TCA, and 7.1 mg sialic acid/g casein soluble in 2% or 12% TCA, respectively. The corresponding figures for immobilized pepsin were 4.97, 4.30 and 6.7. It was concluded that almost (90%) of glycosylated portion of camel casein micelle is on the micelle surface.
Samir K. Abdullah and Suad A. Kadhum
Seeds of 9 cultivars of Sorghum sp. (Sorghum bicolor (L) Moench) were screened for their mycoflora. The seeds were associated with 38 species of fungi belonging to 22 genera. Alternaria alternata, Aspergillus fumigatus, A. niger, A. flavus, Curvularia lunata, Drechslera spicifera, D. australiensis and Fusarium moniliforme were the most frequent species. The clotter method detected more species than the agar plate method. From 29 to 92.6% of the seeds were infected with fungi, and their percentage germination ranged from 21 to 85.6%. The species composition and percentage germination of Sorghum seeds differed among cultivars. Fusarium moniliforme and Aspergillus fumigatus were recovered from seed embryos. Discoloured seeds had a higher incidence of fungi and lower percentage germination compared to clean seeds.
Youssry E. Saleh, Mohamed I. Naguib and Afaf A. Amin
The effect of 24 different amino acids on 40 selected members of Enterobacteriaceae and other pathogenic bacteria was studied. The results showed that iso-leucine and α- amino butyric acid were the least inductive amino acids for amylase production by the tested organisms (21-23 species) whereas histidine; lysine or arginine; threonine and valine were most efficient (35, 34, and 33 members respectively). These were followed by aspartic acid (32 organisms), glutamic acid, hydroxyproline, tyrosine (31 species); methionine, phenylalanine tryptophan (29 members); n-leucine, proline (28 members); cysteine, cystine, ornithine (27 organisms).
Within these amylase producing organism, Klebsiella and Pseudomonas responded very highly, showing a very remarkable activity with 15 amino acids. These were followed by Vibrio ogawa (11 amino acids); V. inaba (10 amino acids). Furthermore, although all tested amino acids released amylase in Yersinia media, yet none of them was able to stimulate high potentialities comparable with those of the other organisms. In the meantime, several amino acids (from 9-18) did not allow for the release of the enzyme whereas the rest favoured a very low activity within the two species of Erwinia and the three strains of E. coli.
A scheme to differentiate the test organisms, based on induction of high amylase activity through amino acid feeding is proposed.