aaelkhatib

Ahmed Ali Ahmed El-Khatib اد/ احمد الخطيب

Professor -

Faculty of science

Address: سوهاج ، مصر

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التعليم العالى العربى القيمة المضافة و تحديات التنمية
يمثل هذا الكتاب واحدة من مكونات السلسة الثقافية التي يقوم الكاتب باعداها و نشرها من واقع خبرته الميدانية في عمليات التطوير و التحديث و ارساء منظومة ادارة الجودة الشاملة بمؤسسات التعليم العالي، وكذلك المساهمات العلمية و الفكرية و التربوية لمن قادوا لواء التطوير و التحديث في هذا المجال و الموضح آرائهم عبر صفحات هذا الكتاب. لقد اهتم هذا الكتاب بصورة ... Read more

BIO-MONITORING OF RADIONUCLIDES AIR POLLUTION USING physiological responses of urban trees
Contamination of environment by radionuclides in territories under urboecosystem conditions is an actual problem. The search for new express methods for radioactivity determination of environment is an important task of research. The present work evaluated the ability to use Eucalyptus globulus leaves to act as bio-monitor for environmental radionuclides air pollution. The accumulation features of radionuclides (226Ra, 232Th, 40K) in ... Read more

2017 | Keywords Spherules, Ferromagnetic, IRM,
Characterizing of Air Dust Particulate Pollutants Using Urban Trees Leaves
Dust accumulated on the tree leaves of six common tree species in the urban area of sohag, Egypt was investigated. Morphological and chemical composition of the dust particles were analyzed using a high resolution scanning electron microscope equipped with an energy-dispersive X-ray analyzer (HRSEM/EDX)and atomic absorption spectrophotometer. Also, their magnetic properties were studied Results showed that the shape of dust ... Read more

Response of duckweed to lead exposure: phytomining, bioindicators and bioremediation
The ability of aquatic macrophytes to bioaccumulate toxic metals relative to the concentrations of these metals in wastewater has led to their use as phytoremediators. Lead (Pb) is among the most serious environmental contaminants. This study assesses the gibbous duckweed (Lemna gibba L.) as a bioaccumulator and bioindicator of Pb pollution. The plant recovery from a 12-d exposure period in ... Read more

Milkweed allelopathy in the agroecosystem
Laboratory experiments were conducted to evaluate the allelopathic effects of different concentration (5, 10, 20, 30, 40, 50%) of Calotropis procera(Aiton) W.T. leaf aqueous extractusing different indices for germination, seedling and physical growth of wheat (Triticum aestivum) and black mustard (Brassica nigra). Except for germination speed, results indicated that the extracts have such allelopathic potential which can significantly reduce the ... Read more

Differential tolerance to high salt with regard to cell growth and superoxide dismutase (SOD) activity in calluses of the halophyte Suaeda maritima from Japan and Egypt
To determine the mechanism of regulation of superoxide dismutase (SOD; EC 1.15.1.1) isozymes in halophytes at the cellular level,we isolated calluses from Suaeda maritima plants native to Japan and Egypt. Calluses from Egyptian S. maritima could grow in a high salt medium (~400 mM NaCl), whereas Japanese S. maritima calluses could not. The expression characteristics of SOD isozyme genes encoding ... Read more

Urban Tree Leaf as Bio-indicator for Air Pollution around Superphosphate Fertilizers Plant, Upper Egypt
For the purpose of this study, two common tree species namely: Ficus nitida and Eucalyptus golobulus were selected in the areas surrounding Asyut Superphosphate Fertilizer Plant, Upper Egypt. Physiological and anatomical responses of tree leaf due to airborne particles deposition were studied. Leaves exhibited reduction in their surface area, dry weight, chlorophyll contents, and an increase of carotenoids content. Anatomical ... Read more

Growth And Physiological Response Of Some Cultivated Species Under Allelopathic Stress Of Calotropis Procera (Aiton) W.T
The present work through light on the role of allelopathic potential of Calotropis procera on some growth and physiological parameters of three cultivated crops. The selected species, namely; cucumber, tomato, and wheat were grown in a pot experiment under six different concentrations of aqueous leaf extract ranged from 0 % to 50 % (w/v) with 10 % intervals for one ... Read more

Characterization of the superoxide dismutase genes of the halophyte Suaeda maritima in Japan and Egypt
The expression characteristics of superoxide dismutase (SOD; EC 1.15.1.1) isozyme genes from halophytic _Suaeda marit__ima_ plants native to Japan and Egypt were analyzed using young plants grown under aseptic conditions. A phylogenetic tree based on internal transcribed spacer sequences suggested that Egyptian _S_. _maritima_ is related to European and India _S_. _maritima_, while Japanese _S_. _maritima_ belongs to a separate ... Read more

Bioaccumulation Potential and Physiological Responses of Aquatic Macrophytes to Pb Pollution
In view of their potential bioaccumulation of heavy metals, Ceratophyllum demersum and Myriophyllum spicatum was studied under hydroponic cultures enriched by different Pb concentrations (25, 50, 75 mg/l) for 1–7 days. Both species exerted remarkable capabilities to concentrate Pb in their tissues as compared to control. The highest accumulation value of Pb (164.26 mg/g.dw) was recorded in C. demersum and ... Read more