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Using System Dynamics for Simulating Subsurface Drainage Systems in Clay Soils

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Journal of Water Resource and Protection 2019年第5期11卷 529-539页

作者： alaa el-sadek Mona Radwan Arabian Gulf University Manama Kingdom of Bahrain National Water Research Center Nile Research Institute Cairo Egypt

The system dynamics technique is used as a decision tool for engineering problems. It is one of the object oriented approaches that study and manage complex feedback systems. In this paper, the system dynamics technique was used to simulate the performance of a drainage system under wheat crop in a clay soil. The model was calibrated and validated using observed experimental field data (drainage discharge and water table level) collected from Mashtul Pilot Area (MPA), Egypt. The results indicated that, the model is capable to predict hydrological parameters such as water table fluctuation, drainage discharge, upward flux, evapotranspiration, deep percolation, infiltration, runoff, soil moister content and unsaturated hydraulic conductivity on the basis of variation of soil moister content. The trends of the parameters found to be legible. Six statistical indexes were calculated to determine the agreement between the observed and simulated values of water table and drainage discharge. Results indicated that the system dynamics technique can be considered as a good decision tool to predict the subsurface drainage water precisely.

关键词： Subsurface Drainage System Dynamics MPA Statistical Analysis

Modeling of Water Flow and Nitrate Transport to Subsurface Drains

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Journal of Agricultural Chemistry and Environment 2018年第1期7卷 45-59页

作者： alaa el-sadek Mona Radwan Arabian Gulf University Manama Kingdom of Bahrain Regional Water Energy and Food Center Zewail City Egypt Nile Research Institute National Water Research Center ElQanater ElKhairia Egypt

In this study,?the water flow and nitrate transport to a subsurface drain, using a simplified and detailed model, are simulated for the specific hydro-geological conditions of elverdinge and Assenede, Belgium. Previously, the DRAIN?MOD-N model proved to be able to simulate nitrate concentrations and drainage well for an?in-situleaching experiment, the?“Hooibeekhoeve”?in the community of Geel (north-eastern part of Belgium), conducted in 1992-1995. In this study, the calibrated model is used to simulate the nitrate leaching for the winter period 2000-2001 in elverdinge and Assenede and is compared to a model with a simplified nitrate transport description. The comparative analysis between both model approaches reveals that the simplified model is able to predict sufficiently accurate the observed nitrate leaching. The detailed approach however has the advantage of giving?a more accurate estimate of the nitrogen mineralization, N deposition and denitrification, resulting in a more precise modeling of the nitrate leaching to surface waters and groundwater.

关键词： Non-Point Source Subsurface Drainage Nitrogen Cycle Nitrate Leaching Water Quality

A Comparative Analysis for a Novel Irrigation Method: Partial Rootzone Drying

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Journal of Agricultural Chemistry and Environment 2018年第1期7卷 34-44页

作者： alaa Abdallah el-sadek Mona Ezo Radwan Ahmed Ali Salih Arabian Gulf University Manama Kingdom of Bahrain Nile Research Institute National Water Research Center El Qanater El Khairia Egypt

Partial Rootzone Drying (PRD) is an irrigation technique which offers a means of modifying the growth and development of crops through relatively simple changes to the method of water delivery. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. Partial drying of one half of the roots of plants grown with two root systems is rapidly translated into a reduction in transpiration and assimilation of all the crop leaves. The aim of this research is to examine and simulate the novel irrigation method (PRD), which would stimulate the endogenous stress response mechanisms of Conocarpus erectus trees in the pilot area of the Arabian Gulf University in Bahrain and wheat and maize crops in the Mashtul Pilot Area (MPA), Egypt using Saltmed model so that vigor is reduced and the efficiency of water use is enhanced. This is to be achieved by the manipulation of the hydration status of parts of a crop’s roots that could be used to control vegetative vigor without detrimental effects on canopy water relations. The PRD technique is researched for wheat as a winter crop and maize as a summer crop in Egypt. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. The results confirmed an increase in irrigation water use efficiency using PRD comparing with conventional flood irrigation. The research highly recommends applying the PRD method in the Gulf Cooperation Council (GCC) countries and in new reclaimed areas in Egypt to save water and improve crop quality.

关键词： Partial Rootzone Drying Conocarpus Erectus Trees MPA GCC

Assessment of the Water-Energy Nexus in the Municipal Water Sector in Eastern Province, Saudi Arabia

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Computational Water, Energy, and Environmental Engineering 2018年第1期7卷 1-26页

作者： Homoud Al-Mutrafi Waleed Al-Zubari alaa el-sadek Ibrahim Abdel Gelil Research and Development Center Saudi Aramco Dhahran KSA College of Postgraduate Studies Arabian Gulf University Manama Bahrain

When it comes to water and energy, it is hard to obtain one without the other. Water is required to produce energy and energy is necessary in water production and management. As demands for water are escalating due to rapid population growth and urbanization, understanding and quantification of the interdependency between water and energy, along with analyzing nexus interactions, trade-offs and risks are a pre-requisite for effective and integrated planning and management of these two key sectors. This paper performs an assessment of the water-energy nexus in the municipal sector of the Eastern Province of Saudi Arabia, where the electric energy footprint in the water value chain (groundwater, desalination and wastewater treatment) and the water footprint in electric energy generation (thermal power plants) are quantified using data for the year 2013. The results confirmed the high and strong dependency on energy for the municipal water cycle in the Eastern Province and revealed that energy generation dependency on freshwater resources is also major and evident, especially at farther distances from the coastal areas. Thermal desalination is by far the most energy intensive stage among the entire Eastern Province water cycle. In 2013, it was estimated 13% of the Eastern Province energy generation capacity goes for desalination, that’s a 5% of the Kingdom capacity. Substantial energy input for desalination in the Eastern Province is attributed to the production and conveyance of water to the Capital Riyadh (48.9 kWh/m3 and 4.2 kWh/m3 respectively). As for groundwater pumping, it was estimated that 206.2 GWH was used for pumping 268 MCM in 2013 (0.764 kWh/m3). Energy requirement for primary, secondary and tertiary wastewater treatment was found to be the least (2 - 108 GWH) and was equivalent to an average of 0.4 kWh/m3. The water footprint in electricity generation was estimated to be about 739,308 m3 in 2013 (0.125 m3/kWh), a relatively higher value compared to the n

关键词： Thermal Power Plant Environmental Impact Carbon Footprint Energy Recovery Management and Mitigation

Characterization of the Outfall Area of a Multi-Stage-Flash Desalination Plant in Bahrain

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Journal of Water Resource and Protection 2018年第3期10卷 287-303页

作者： Waleed K. Al-Zubari alaa A. el-sadek Mohamed J. Khadim Water Resources Management Program College of Graduate Studies Arabian Gulf University Manama Kingdom of Bahrain

In Bahrain, like the other Gulf Cooperation Council (GCC) countries, desalination is inevitable to meet the escalating municipal water demands. However, desalination is associated with many environmental effects, which need to be minimized to their lowest possible limits. One of the major environmental concerns of desalination in the Arabian Gulf region is the local and regional effects of the outfall areas on the marine environment. In this study, the outfall area of a government-owned MSF desalination plant is characterized in terms of temperature and salinity. The spatial extent of the plume of the desalination plant’s effluent is mapped by a field survey conducted during the winter season around the plant’s outfall area at 25 cm and 1 m below the water surface and at low and high tide. The results of the characterization indicated that the temperature of the brine discharged to the outfall was 37°C, higher than the ambient seawater temperature by 16.5°C at high tide and 17.5°C at low tide, and that the extent of the mixing zone area was found at about 260 m and 1 km from the outfall point at high tide and low tide, respectively. The results also showed that brine thermal discharge is not in compliance with the standard limits (eline) both at high and low tides with differences reaching more than 10°C. In terms of salinity, the brine discharged salinity was 56.2 parts per trillion (ppt) compared to an ambient seawater salinity of 43.2 ppt. The maximum salinity measured near the outfall point was 56 ppt at low tide and 51 ppt at high tide, both at 1 m below the surface water column. It is found that the current design structure consisting of two jetties to isolate the desalination plant outfall area from its surroundings is not environmentally sound, as the current surface/inter-tidal outfall location is susceptible to significant increases in salinity and temperature around the outfall area due to the limited flushing it expe

关键词： Desalination Brine Salinity Temperature GCC Countries Bahrain

Hematobiochemical and histopathological alterations in Nile Tilapia(Oreochromis niloticus)exposed to ethidium bromide:The protective role of Spirulina platensis

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Aquaculture and Fisheries 2024年第1期9卷 93-103页

作者： Sabreen Abdullah Mervat Naguib alaa el-Din Salah el-Din alaa el-Din H.Sayed Zoology Department Faculty of ScienceAswan UniversityAswan81528Egypt Zoology Department Faculty of ScienceAssuit UniversityAssiut71516Egypt

Ethidium bromide(EtBr)is one of the contaminants recorded in aquatic environments whose effects have been investigated;however,there is still limited knowledge about its *** study examined the potential protective effects of Spirulina platensis(SP)against the effects of EtBr toxicity in the Nile tilapia(Oreochromis niloticus)*** were divided to five groups,viz.,a control and four treatment groups of low-dose EtBr(10μg/L),low-dose EtBr with SP(10μg/L EtBr+200 mg/L SP),high-dose EtBr(100μg/L),and high-dose EtBr with SP(100μg/L EtBr+200 mg/L SP);the exposure period was 2 *** and high doses of EtBr induced alterations in some hematological,biochemical,and histopathological *** hepatocytes,degenerated area,vacuolated hepatocytes,pyknotic nuclei,constricted and dilated blood sinusoids,and infiltration of inflammatory cells were *** peroxidation concentration was not significantly different in groups exposed to low doses of EtBr and EtBr with SP,but it was increased in groups exposed to high doses of EtBr and EtBr with SP,compared with the control *** feeding with SP,most histological and histochemical parameters restored to normal ***,SP may possess the ability to preserve the structural integrity of the hepatic and renal membranes.

关键词： Ethidium bromide Spirulina platensis Oreochromis niloticus Liver Lipid peroxidation

Percutaneous Mesh Expansion and Fixation at the Retro-Rectus Plane without Stabs by Using Redirecting Suture Hook in Midline Hernias Repair

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Surgical Science 2011年第4期2卷 177-182页

作者： Ahmed E Lasheen alaa N. el sadek Adel M Tolba Emad Salah Ayman F Mehanna 不详

Background: Mesh expansion and fixation at retro-rectus plane through multiples stabs produces good results. But these stabs cause cosmetic disorders for the patients and doctors. So, we find some modification to do this procedure without these stabbing wounds in midline hernial repair. Patients and methods: This technique was used to fix the mesh at retro-rectus plane in 50 patients suffering from midline hernias, from January 2008 through January 2010 at Zagazig university Hospital, Egypt. Laparotomy incision was done over the hernial sac or at old incision;the contents were then released and reduced into peritoneal cavity without much subcutaneous dissection. The suitable sheet of polypropylene mesh to cover the hernial defect and any weak area was prepared and fixed at retro-rectus plane percutaneously without stabbing wounds by using redirecting suture hook. The mean period of follow up was 26 months. Results: There was no recurrence during the period of follow up. Five patients developed subcutaneous bluish discoloration at the site of some stitches, which disappear within two weeks with conservative treatment. Conclusion: Percutaneous mesh expansion and fixation at retro-rectus plane by using redirecting suture hook procedure has good results in recurrence rate and cosmetic appearance.

关键词： Percutaneous Fixation Retro-Rectus Mesh Redirecting Suture Hook

Magneto-Photo-Thermoelastic Excitation Rotating Semiconductor Medium Based on Moisture Diffusivity

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 107-126页

作者： Khaled Lotfy A.M.S.Mahdy alaa A.el-Bary E.S.elidy Department of Mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of Mathematics Faculty of ScienceTaibah UniversityMadinah42353Saudi Arabia Department of Mathematics and Statistics College of ScienceTaif UniversityTaif11099Saudi Arabia Arab Academy for Science Technology and Maritime TransportAlexandria1029Egypt

In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture *** problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic *** study examines the photothermoelasticity transport process while considering the impact of moisture *** employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic *** equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive *** stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace *** employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under ***,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.

关键词： Moisture diffusivity semiconductor photothermoelastic rotation thermomechanical waves laplace transform

Evaluation of the nutritional value of Artemia nauplii for European seabass(Dicentrarchus labrax L.)larvae

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Aquaculture and Fisheries 2024年第1期9卷 78-84页

作者： alaa A.el-Dahhar Rashwan S.Rashwan Samy Y.el-Zaeem Shaimaa A.Shahin Mona M.Mourad Mohammed F.el Basuini Animal and Fish Production Department Faculty of Agriculture-Saba BashaAlexandria UniversityAlexandria21526Egypt National Institute of Oceanography and Fisheries(NIOF) Cairo11562Egypt Department of Animal Production Faculty of AgricultureTanta UniversityTanta31527Egypt Faculty of Desert Agriculture King Salman International UniversitySouth Sinai46618Egypt

Adapted European seabass(Dicentrarchus labrax L.)larvae at 25 days post-hatching(dph)with a primary weight and length of 23 mg and 9.92 mm,start the weaning up to 46 dph using the weaning micro-diet(54%crude protein from fish meal,powder milk,and poultry egg)concurrently with Artemia enriched with fortification emulsions(0.6 g/L)of DHA selco®as a control group(DHAS)or Fish oil+20%Vitamin C(FOVC),or Fish oil+20%Vitamin E(FOVE),or Fish oil+10%Vit.C+10%Vit.E(FOCE),or Fish oil only(FO).At 46 dph,groups of larvae fed enriched Artemia with DHAS and FOVE exhibited the highest final body weight,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the lowest feed conversion ***,larvae in FOVC displayed the lowest final body weight,total length,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the highest feed conversion *** histological assessment exhibited no pathological alteration as well as an improvement in the structure with DHAS,FOVE,FOVC,and FOCE co-additives compared to *** peroxidase enzyme(GPx)recorded the highest rates(P<0.05)in groups fed Artemia supplemented with DHAS and FOVE followed by FOCE and *** the lowest record for GPx activity was noted in the FO *** conclusion,Using augmented Artemia nauplii with fish oil+vitamin E in single or in companion with vitamin C as cheap antioxidants support *** larval growth,survival,and antioxidant efficacy during the critical weaning period.

关键词： European seabass Gastrointestinal histology Antioxidants Vitamin C Vitamin E DHA