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Search Results: 1 - 10 of 31180 matches for " Ali El-Shaar "
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Adsorption Studies of Lead by Enteromorpha Algae and Its Silicates Bonded Material
Hassan H. Hammud,Ali El-Shaar,Essam Khamis,El-Sayed Mansour
Advances in Chemistry , 2014, DOI: 10.1155/2014/205459
Abstract: Lead adsorption by green Enteromorpha algae was studied. Adsorption capacity was 83.8?mg/g at pH 3.0 with algae (E) and 1433.5?mg/g for silicates modified algae (EM). FTIR and thermal analysis of algae materials were studied. Thomas and Yoon-Nelson column model were best for adsorbent (E) and algae after reflux (ER) and Yan model for (EM) with capacity 76.2, 71.1, and 982.5?mg/g, respectively. (ER) and (EM) show less swelling and better flow rate control than (E). Nonlinear methods are more appropriate technique. Error function calculations proved valuable for predicting the best adsorption isotherms, kinetics, and column models. 1. Introduction The contamination of wastewater and soil with heavy metal ions is a complex problem, since these metals are toxic in both their elemental and chemically combined forms. Natural water is contaminated with several heavy metals due to their widespread use in industry and agriculture arising mostly from mining wastes and industrial discharges. From an environmental protection point of view, heavy metal ions should be removed at the source in order to avoid pollution of natural waters and subsequent metal accumulation in the food chain. In fact, removal of this contamination has received much attention in recent years [1, 2]. Lead being one of the “big three” toxic heavy metals, it is of profound concern as a toxic waste and contaminant of surface waters as it becomes concentrated throughout the food chain to humans [3]. Lead damages different body organs (central and peripheral nervous systems and kidney); also, lead has a teratogenic effect, causing stillbirth in women and affecting the fetus [4]. Conventional methods for removal are chemical precipitation, chemical oxidation, chemical reduction, ion exchange, filtration, electrochemical treatment, and evaporation [5, 6]. These methods often are very expensive. Alternative method for heavy metal removal was developed in the last past decade and known as biosorption. Marine algae, an abundant renewable natural biomass, have been used as dead nonliving materials for removal of heavy metals [7, 8]. In addition, algae were found accumulating heavy metal in their habitat and are thus used as heavy metal pollution monitors in fresh and salty water such as river, sea, and ocean. They have been also used in on-site bioremediation of polluted natural water [9, 10]. Furthermore, the search for a low-cost and easily available adsorbent has led to the investigation of materials of agricultural and biological origin (bacteria, fungi, yeast, and algae can remove heavy metals
Retraction: An Improved Approach of Surface Meshes  [PDF]
Bashar Zogheib, Ali El Saheli
Applied Mathematics (AM) , 2015, DOI: 10.4236/am.2015.63048
Abstract: The article has been retracted due to the authors’ strong personal reason about the indexing databases of Applied Mathematics.
Waterlogging in the New Reclaimed Areas Northeast El Fayoum, Western Desert, Egypt, Reasons and Solutions  [PDF]
El Sayed Ali El Abd, Maged Mostafa El Osta
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.618147
Abstract: The waterlogging in the new reclaimed areas has become a major concern in the area Northeast El Fayoum, Western Desert, Egypt. It is not only endangering the structures and properties but also causing major environmental problem affecting the health of the area, habitats, and the biotic of the land community, as well as the deteriorating of Egypt’s Pharaonic monuments (El Lahun and Hawarah pyramids). Both the daily seepage from excess irrigation water and the presence of impervious clay or limestone beds at shallow depths may represent the main contributor of ground-water rising in the shallow aquifer. This paper investigates the interplay of the hydrogeological characteristics, soil properties and recent land reclamation projects on the distribution of waterlogging and salinization within the study area. The field observations show that new reclaimed areas have been recently cultivated in distant areas from the old agricultural land. These new cultivations have developed widespread waterlogging, soil salinization and deterioration of Egypt’s Pharaonic monuments as a result of rising groundwater related problems. In this paper, the data used come from database of drillings for eleven observation wells distributed inside the whole area to measure periodic water levels. The soil litho-units are mainly composed of coarse sand, sandy clay, silt and fractured limestone underlined by impervious clay or limestone, thus limiting the downward percolation of excess irrigation water and therefore develops waterlogging. The drainage networks and suitable irrigation methods have to be considered when planning for a new cultivation in dry land to better control waterlogging and salinization hazard. It is highly recommended in this research that newly small and deep cut drainage canals network should be constructed and connected to the master drainage canal to dewater the excess irrigation water and to prevent the waterlogging in the concerned area.
Severe war trauma and post-traumatic stress disorder in adolescents with sensory impairments: a cross-sectional study
Khuzama Hijal Shaar
Health Psychology Research , 2013, DOI: 10.4081/hpr.2013.e16
Abstract: A paucity of studies of the psychological status of adolescents with sensory impairments in political conflict areas is noted. This study was set up to examine the exposure of adolescents with sensory impairments (ASIs) to severe war trauma and development of post-traumatic stress disorder (PTSD) as compared to their able-bodied peers (ABPs). It also answers the question whether their impairments have made them more resilient in facing traumatic events. A cross-sectional study of all ASIs attending special schools in three administrative districts in Lebanon (n=166) as well as a group of 166 age and sex-matched ABPs from neighboring schools was conducted. The Post Traumatic Stress Reaction Checklist for children (PTSRC) was used to assess exposure to severe trauma, PTSD and their determinants. ASIs reported a lower exposure to severe traumatic events (24.1%) as compared to their ABPs (69.9%), and risk factors for their exposure were an older age group, a fatherless family, and severe visual impairment. Prevalence rates for PTSD were similar in the two study groups (17.5% and 16.4%). Younger ASIs were at a significantly higher risk of developing PTSD. Lower exposure to trauma among ASIs points to the more sheltered life that they lead. Given the same exposure as ABPs, similar rates of PTSD are noted among the two study groups. This may indicate that having a sensory impairment may protect from PTSD due to decreased exposure to severe trauma and not due to increased resilience of subjects.
Bioadsorption of Pb(II) onto Anethum graveolens from Contaminated Wastewater: Equilibrium and Kinetic Studies  [PDF]
Ali Hashem, Khalid El-Khiraigy
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.41012
Abstract:

In the present study we reported the feasibility of the Anethum graveolens as biosorbent to remove Pb(II) from aqueous solutions. Anethum graveolens was characterized by scanning electron microscopy and elemental analysis. The ability of Anethum graveolens to adsorb Pb(II) was investigated by using batch adsorption procedure. The effects such as pH, contact time, adsorbate concentration and biosorbent dosage on the adsorption capacity were studied. The experimental data were analysed using various adsorption kinetic models viz., the pseudo-first and second-order equations, Bangham’s equation, intraparticle diffusion and Elovich models. Results show that the pseudo-second-order equation provides the best correlation for the biosorption process. The equilibrium nature of Pb(II) adsorption at 30 has been described by the Langmuir, Freundlich, Temkin and Redlich-Peterson isotherm models. The equilibrium data fit well on Langmuir isotherm. The monolayer adsorption capacity of Pb(II) onto Anethum graveolens as obtained from Langmuir isotherm at 30 was found to be 303 mg/g. This high adsorption capacity of Anethum graveolens places this biosorbent as one of the best adsorbents for removal of Pb(II) from aqueous effluents.


Constrained Feedback Stabilization for Bilinear Parabolic Systems  [PDF]
Azzeddine Tsouli, Ali Boutoulout, Abdessamad El Alami
Intelligent Control and Automation (ICA) , 2015, DOI: 10.4236/ica.2015.62011
Abstract: In this paper, we shall study the stabilization and the robustness of a constrained feedback control for bilinear parabolic systems defined on a Hilbert state space. Then, we shall show that stabilizing such a system reduces stabilization only in its projection on a suitable subspace. For this purpose, a new constrained stabilizing feedback control that allows a polynomial decay estimate of the stabilized state is given. Also, the robustness of the considered control is discussed. An illustrating example and simulations are presented.
PALSAR-FBS L-HH Mode and Landsat-TM Data Fusion for Geological Mapping  [PDF]
Abderrazak Bannari, Ali El-Battay, Ali Saquaque, Abdelhafid Miri
Advances in Remote Sensing (ARS) , 2016, DOI: 10.4236/ars.2016.54020
Abstract: Characterized by lithological diversity and rich mineral resources, Benshangul-Gumuz National Regional State located in Asosa Zones, Western Ethiopia has been investigated for geological mapping and morpho-structural lineaments extraction using PALSAR (Phased Array type L-band Synthetic Aperture Radar ) Fine Beam Single (FBS) L-HH polarization and Landsat-5 TM (Thematic Mapper ) datasets. These data were preprocessed to retrieve ground surface reflectance and backscatter coefficients. To overcome the geometry acquisition between the two sensors, they were geometrically and topographically rectified using ASTER-V2 DEM. Intensity-Hue-Saturation, directional filters and automatic lineaments extraction were applied on the datasets for lithological units’ discrimination and structural delimitation for potential mineral exploration. The obtained results showed good relationship among the topographic morphology, rock-substrate, structural variations properties, and drainage network. The spectral variations were easily associated with lithological units. Likewise, the morpho-structural information highlighted in the PALSAR image was visible without altering the radiometric integrity of the details in TM bands through the fusion process. Moreover, predominant lineaments directions trending NE-SW, NS, and NW-SE were identified. Results of this study highlighted the importance of the PALSAR FBS L-HH mode and TM data fusion to enhance geological features and lithological units for mineral exploration particularly in tropical zones.
On the Electrical and Thermal Conductivities of Cast A356/Al2O3 Metal Matrix Nanocomposites  [PDF]
El-Sayed Youssef El-Kady, Tamer Samir Mahmoud, Ali Abdel-Aziz Ali
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.29159
Abstract: To assess the effect of the dispersion of Al2O3 nanoparticles into A356 Al alloy on both the electrical and thermal conductivities, A356/Al2O3 metal matrix nanocomposites (MMNCs) were fabricated using a combination of rheocasting and squeeze casting techniques. Two different sizes of Al2O3 nanoparticles were dispersed into the A356 Al alloy, typically, 60 and 200 nm with volume fractions up to 5 vol%. The effect of the nanoparticles size and volume fraction on the electrical and thermal conductivities was evaluated. The results revealed that the A356 monolithic alloy exhibited better electrical and thermal conductivities than the MMNCs. Increasing the nanoparticles size and/or the volume fraction reduces both the thermal and electrical conductivities of the MMNCs. The maximum reduction percent in the thermal and electrical conductivities, according to the A356 monolithic alloy, were about 47% and 38%, respectively. Such percentages were exhibited by A356/Al2O3MMNCs containing 5 vol% of nanoparticles having 60 and 200 nm, respectively.
Positron-Excited Lithium Atom Collisions  [PDF]
Salah Y. El-Bakry, El-Sayed A. El-Dahshan, Khadija Ali
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.46105
Abstract:

The inelastic scattering of positrons by excited lithium alkali atoms Li*(2p) have been investigated within the frame work of the coupled-static and frozen-core approximations with the assumption that the elastic and rearrangement channels are open. In the present work, a rather complicated computer code is developed based on the coupled-static, frozen-core and Greens function partial wave expansion technique. The partial and total elastic and positronium (Ps) formation cross sections of e+-Li*(2p) are calculated through a wide range of incident energy of positrons ranging from 0.3 eV to 1000 eV. Also, we have calculated the partial and total elastic and rearrangement (reversal of the Ps formation) cross sections of Ps-Li+ collisions through the low, intermediate and high energy regions. The effect of polarization potential of the Ps atom is taken into our consideration. The total cross sections which corresponding to twelve partial cross sections (calculated at twelve values of the total angular momentum l = 0 to

Treatment of Resistant Clubfoot with Soft Tissue Release and Alkhooly External Fixator  [PDF]
Ali Zein A. A. Al-Khooly, Mohamed Ali Ahmed Mohamed, Ebrahim El-Hawary Ali
Open Journal of Orthopedics (OJO) , 2013, DOI: 10.4236/ojo.2013.37058
Abstract:

After the first research with this technique done by the first author, ten operations on the foot and ankle were performed on five patients (two boys and three girls) suffering from severe club foot deformity all with bilateral foot affection. Their ages ranged from five to fourteen years. All of them were treated by soft tissue release, skin flap (rotational flap), supplemented with Alkhooly external fixator. The follow up period ranged from two to seven years. The results according to Mittal (1987) [1] were excellent in eight feet (80%) and good in two feet (20%).

 

 

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