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Abstract  

The Bio-Rex 5 resin was used for the recovery of 123I, producedin a cyclotron by irradiation of a 124 Xe target. Initially fouranion exchange resins AG1-X8, AG2-X8, Amberlite IRA-93 and Bio-Rex 5 wereused, but none of them gave good separations. Bio-Rex 5, consisting of a largeportion of tertiary and a smaller portion of quaternary amino groups, wasthen modified so that the resin contained only tertiary amine functional groupsand this modified resin was used for the separation. The concentrations ofiodide solutions were ca 5 ppb and the volumes about 120 ml. For measurementof iodide, 131I was added as tracer. In this study 6 columns ofvarious sizes were used and the best of them, in terms of maximum recoveryand minimum volume of NaOH for elution, was selected for routine production.

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Abstract  

The stability constants of UO 2 2+ -squarate complexes are measured at ionic strengths of 0.05M, 0.06M, 0.075M, 0.09M, 0.1M (squaric acid-perchloric acid) using a solvent extraction method at a pH of 1.1 and a temperature of 25 °C. The extractant used is dinonylnaphthalenesulfonic acid in n-heptane. The aqueous phase was made of a mixture of squaric and perchloric acid and233U radio tracer. The stability constants of squarate complexes of UO 2 2+ is seen to decrease linearly with the square root of the ionic strength.

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Journal of Thermal Analysis and Calorimetry
Authors:
H. El-Boraey
,
F. El-Saied
, and
S. Aly

Abstract  

UO2(VI), Sn(IV), Th(IV) and Li(I) complexes of 4-azomalononitrile antipyrine (L) have been isolated and characterized based on IR spectra, 1H NMR, elemental analyses, molar conductance and thermal analysis (DTA/TG). The study revealed that the ligand behaves as a neutral bidentate one and coordination takes place via the carbonyl atom of pyrazolone ring >C=O and the azomethine nitrogen >C=N. The thermal stability of the metal complexes were investigated by thermogravimetry (TG), differential thermal analysis (DTA) techniques and infrared spectra, and correlated to their structure. The thermal study revealed that Th(IV) complexes show lower thermal stability than both UO2(VI) and Sn(IV) complexes.

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In this study, two green microalgae, Dunaliella bardawil and Chlorella ellipsoidea , are exposed to different pH values. The two tested microalgae could grow in a wide range of pH (4–9 for D. bardawil and 4–10 for C. ellipsoidea ). The dry weight gain and the biochemical components of D. bardawil were greatly enhanced at pH 7.5. On the contrary, dry weight and carbohydrate content of C. ellipsoidea attained their maximum values at the alkaline pH. On the other hand, the protein content of C. ellipsoidea recorded its highest value at pH 4, while the pigment content of the same alga highly accumulated at pH 4, 6 and 7.5 and decreased as pH directed to the alkaline side. Both pH 6 and pH 9 stimulated the accumulation of vitamin E and vitamin C in D. bardawil , with the highest values of the three compounds recorded at pH 9. In case of C. ellipsoidea , β-carotene content increased at pH 6 and 10 as compared with control, but the amount of β-carotene was much higher at pH 6 than at pH 10. Contrarily, vitamin E was highly accumulated in C. ellipsoidea cells at pH 10 than at pH6. BothpH6 andpH10 caused a significant decline in vitaminCcontent in C. ellipsoidea .

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The objective of this study was to investigate the effect of soil drench with three different concentrations of CdCl2 on pigments content, photosynthetic activity, carbohydrate contents and productivity of Sorghum bicolor L. cv. 'Dorado' plants throughout various stages of plant growth and development. Also particular interest was focussed on the effect of grain presoaking with kinetin to ameliorate the toxicity effects exerted by the different levels of CdCl2. In the majority of cases, grain pretreatment with kinetin increased photosynthetic pigments, photosynthetic activity, Hill reaction as well as carbohydrate contents in leaves of cadmium treated sorghum plants. In general, the observed decrease in yield and yield attributes of sorghum plants in response to Cd2+ treatments was accelerated particularly when grains were presoaked in kinetin. The ameliorating effect of kinetin was more pronounced at 1 mM CdCl2. Grain priming with kinetin increased grain biomass (i.e. fresh and dry weights), carbohydrates, protein and ion contents in yielded grains of cadmium treated sorghum plants. Cadmium treatments altered the balance of growth bioregulators in developed grains of sorghum plants. Thus, CdCl2 at all the used concentrations exerted a significant decrease in growth promotor levels with an increase in growth inhibitory substances equivalent to abscisic acid. On the other hand, grain priming with kinetin increased the growth promotory substances and reduced abscisic acid levels.

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The thermal behaviour of the entitled nickel(II) and copper(II) complexes of ¯4-acetylamino-2-hydroxy-5-methyl azobenzene has been studied by means of differential thermal analysis (DTA), thermogravimetry (TG), X-ray powder diffraction, IR and electrical conductivity. A light has been thrown on the nature of interaction of the solvents of crystallization with the host complex. Some of the kinetic parameters are calculated and discussed.

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Abstract

The study of the bacteriological profile, the association of complement C3, interleukin-1beta, and zinc therapy of diabetic foot ulcers (type two) was investigated. Twenty diabetics without foot ulcers (group I), 50 diabetics with foot ulcers (group II), and 10 matched normal controls (group III) were enrolled in this study. Diabetic foot ulcers were mostly of grade 2. The most frequent organisms were Clostridium spp., Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, respectively. Vancomycin, Imipenem, and Meropenem were the most effective against Gram-positive and Gram-negative aerobes, while Imipenem, Meropenem and Chloramphenicol for Gram-positive anaerobes. Group II had abnormal levels of C3 (72%). A significant higher concentration of C3 was found in group II. Group II had abnormal levels of IL-1β (60%). A significant higher concentration of IL-1β was found in group II. Zinc therapy (25 mg/day/oral) induced a highly significant decrease in the frequency of Gram-positive anaerobes and levels of IL-1β. Significantly increases all mineral concentrations in serum level except Mn+2. The study highlights the prevalence of antibiotic multidrug resistant bacteria causing foot infections in diabetics which require combined antimicrobial therapy. Altered levels of serum complement C3 and IL-1β might be responsible for depressed immune response which might be causes for delayed wound healing and repeated infections. Zinc supplementation may help in healing the wounds by enhancing the immune response.

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Estimation of seismic wave attenuation in the shallow crust in terms of coda wave Q structure previously investigated (Sayed et al. 2002) in the vicinity of Cairo Metropolitan area was improved using seismograms of local earthquakes  recorded by the Egyptian National Seismic Network (ENSN). The seismic wave attenuation was measured in the study area from the time decay of coda wave amplitudes on narrow bandpass filtered seismograms on the basis of the single scattering theory. The frequency bands of interest are from 1.5 Hz to 18 Hz. In general, the values obtained for paths and events foci and El-Fayoum (FYM) and Wadi Hagul Sations (HAG) are very similar for all frequency bands. A regional attenuation law Q c = 85.66 f 0.79 was obtained.

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Summary  

Indomethacin was successfully labeled with 125I. This labeling reaction was carried out via electrophilic substitution of hydrogen atom with the iodonium atom I+. The reaction was found to be strongly dependent on pH of the reaction medium. At neutral pH value, 7 the labeling yield was maximum. This may be due to the good solubility of indomethacin, good protonation and good working of the oxidizing agent at this pH value. Towards the acidic pH value, the yield decreased and towards the alkaline pH value the yield decreased due to the decomposition of the indomethacin. The labeling reaction is very fast but needs five minutes for completion. The produced 125I-indomethacin was found stable in-vivo as the thyroid gland uptake did not exceed 2%. Labeled indomethacin shows a good localization in inflamed muscle, either septic or sterile. It excretes mainly via liver and to some extent via kidney. The imaging must be carried out at 24-hour post injection, after that time, the background activity has cleared and the activity is concentrated in the target site.

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