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Acta Geochimica 2020年第2期39卷 226-235页

作者： maha ahmed mohamed abdallah ahmed mohamed Badr-ElDin Marine Pollution Lab National Institute of Oceanography and FisheriesAlexandriaEgypt Oceanography Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt

A protected semi-enclosed embayment,the Eastern Harbor(EH),is situated in the central sector of the Mediterranean coast of Alexandria,*** is a famous fishing dock and water-sport center and its importance arose after the discovery of the Ptolemaic royal quarter of ancient *** protect this national treasure and improve its environmental health,the untreated anthropogenic effluents,which continued for decades into the EH since 1992,must be totally ***,it is an important issue to continually monitor and asses the environmental status of the *** sediment texture,total organic carbon,and the accumulation,distribution,and ecological risks of Cd,Cr,Pb,As,Hg and A1 were determined with a total of 14 surficial sediments samples collected in the EH during *** contents were compared to the literature data to assess the pollution status of *** factors,Degree of contamination(mCd)and potential ecological risk were calculated as a criterion of possible *** mCd calculation produces an overall average value for a range of pollutants,in the present study the contamination factor that provides a measure of the degree of overall contamination in the surface layers in a particular sampling site may provide a better indication of the state of pollution in the EH sediments than other indicators.

关键词： Heavy metals Eastern harbor Enrichment factors Degree of contamination Potential ecological risk

Mercury speciation in aquatic environment south eastern coast of the Mediterranean Sea,Egypt

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Emerging Contaminants 2020年第1期6卷 194-203页

作者： maha ahmed mohamed abdallah Marine Pollution Lab National Institute of Oceanography&FisheriesAlexandriaEgypt

This study aims to describe distribution and speciation of Hg in coastal water,fish and sediments from the Western harbour(main harbour)in Egypt and has been studied in two *** slightly high annual mean of total dissolved mercury TDHg value(1.81 mg/L)in the surface layer might reflect the highest average surface value(6.09 mg/L),selected at the outer part,due to the entering the water loaded by industrial pollutants from El Mex Bay to the harbour *** addition to the internal activities as petroleum Quay(petroleum basin)and in front of Noubaria Canal outfall(5.13 and 5.32 mg/L respectively).On the other hand,the increased levels of mercury in suspension(particulate form)during the study period may be due to the effects of heavy winter rain over the highly industrialized area,also the surface input of mercury and its regeneration at the sediment/water interface in the *** the present study,the total and methyl mercury in the studied fish was exceeded the regulatory limit of the European Union for mercury concentration in *** contamination of *** species was higher than that of the other studied species due to its habitat,represented by small schools in very shallow water close to the bottom sediments,and its different approach in *** present study of surface sediments reveals that,there were probably an uncomplexed strong Hg-binding site available in the sediments,the major portion of mercury found in these sediments is in organo-chelated form followed by acid reducible ***,mercury in residual fraction(mercury of natural origin)is the relatively low portion *** though the percentage of the first three fractions of mercury is relatively high,absolute values of these mobile Hg fractions are quite high due to the high total mercury values.

关键词： Mercury Water Sediments Fish Mediterranean sea Egypt

DECAY ESTIMATES FOR ISENTROPIC COMPRESSIBLE MAGNETOHYDRODYNAMIC EQUATIONS IN BOUNDED DOMAIN

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Acta Mathematica Scientia 2012年第6期32卷 2211-2220页

作者： mohamed ahmed abdallah 江飞谭忠 School of Mathematical Sciences Xiamen University College of Mathematics and Computer Science Fuzhou University Institute of Applied Physics and Computational Mathematics

In this paper, under the hypothesis that y is upper bounded, we construct a Lyapunov functional for the multidimensional isentropic compressible magnetohydrodynamic equations and show that the weak solutions decay exponentially to the equilibrium state in L2 norm. Our result verifies that the method of Daoyuan Fang, Ruizhao Zi and Ting Zhang I1] can be adapted to magnetohydrodynamic equations.

关键词： Navier-Stokes equations weak solution decay estimates magnetohydrody-namic

Solar thermochemical reactions Ⅱ:Synthesis of 2-aminothiophenes via Gewald reaction induced by solar thermal energy

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Chinese Chemical Letters 2008年第7期19卷 788-790页

作者： Ramadan ahmed Mekheimer mohamed abdallah Ameen Kamal Usef Sadek Chemistry Department Faculty of ScienceEl-Minia UniversityEl-Minia 61519Egypt

Green conditions have been developed for the synthesis of substituted 2-aminothiophenes employing multicomponent reactions of a ketone with active methylene nitrile and elemental sulphur induced by free solar thermal ... 详细信息

关键词： 2-Aminothiophenes Gewald reaction Solar thermal energy

Evaluation of implanted perforated lacrimal punctal plugs using anterior segment optical coherence tomography

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Eye and Vision 2021年第1期8卷 366-373页

作者： Raafat Mohyeldeen Abdelrahman abdallah ahmed mohamed Kamal Elshafei Heba Radi AttaAllah Ophthalmology Department Minia UniversityEl‑MiniaEgypt Ophthalmology Department Minia University HospitalEl‑MiniaEgypt

Purpose:Evaluation of the patency and position of perforated lacrimal punctal plugs implanted for treating punctal stenosis together with quantitative assessment of the precorneal tear film using anterior segment optical coherence tomography(AS-OCT).Methods:In a prospective study,the lower punctum of 54 eyes of 29 patients implanted with perforated punctal plugs were examined using AS-OCT during the early postoperative *** tear meniscus height(TMH)and tear meniscus area(TMA)were ***,the patency of the plug,its position,TMH and TMA were evaluated,and the results were correlated with postoperative *** scale was used for epiphora ***:Using AS-OCT,48(88.9%)plugs were found in proper position while 6(11.1%)were *** lumen of the plugs was completely patent in 47(87%)plugs,partially obstructed in 2(3.7%)plugs and completely occluded in 5(9.2%)*** was a statistically significant postoperative decrease of TMH and TMA(P<0.001)and postoperative epiphora Munk score(P<0.001).Conclusion:AS-OCT is a valuable,reliable,and noninvasive investigative tool that can detect the proper positioning,patency,and contents of the implanted perforated lacrimal punctal plugs in addition to measurement of TMH and TMA.

关键词： AS-OCT Perforated plugs Plugs

Remarks on Classical Solutions to Steady Quantum Navier-Stokes Equations

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 957-962页

作者： mohamed ahmed abdallah Xu-yang SUN Wei-wei WANG Jun-ping YIN School of Mathematical Sciences Xiamen University Xiamen 361005 China Mathematics School & Institute Jilin University Changchun 130012 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

The paper of Dong [Dong, J. Classical solutions to one-dimensional stationary quantum Navier- Stokes equations, J. Math Pure Appl. 2011] which proved the existence of classical solutions to one-dimensional steady quantum Navier-Stokes equations, when the nonzero boundary value u0 satisfies some conditions. In this paper, we obtain a different version of existence theorem without restriction to u0. As a byproduct, we get the existence result of classical solutions to the stationary quantum Navier-Stokes equations.

关键词： quantum Navier-Stokes equations steady solutions stationary solutions Leray-Schauder fixed-point theorem

Magnetically separable and visible light-active Ag/NiCo2O4 nanorods prepared by a simple route for superior photodegradation of atrazine in water

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Progress in Natural Science:Materials International 2020年第2期30卷 160-167页

作者： ahmed Shawky maha Alhaddad R.M.mohamed Nasser S.Awwad Hala A.Ibrahium Nanomaterials and Nanotechnology Department Advanced Materials DivisionCentral Metallurgical R&D Institute(CMRDI) P.O.Box 87 Helwan Department of Mechanical Engineering School of EngineeringThe University of Tokyo Chemistry Department Faculty of ScienceKing Abdulaziz University Research Centre for Advanced Materials Science (RCAMS) King Khalid University Department of Biology Nuclear Materials Authority

Atrazine（ATZ） is a known herbicide used in agriculture and caused many concerns according to its ***,we have prepared NiCo2O4nanorods that can work as a photocatalyst under visible light exposure by Ag loading through a simple *** characterizations revealed the role of Ag for improving the structural,optical and optoelectronic properties of the produced *** Ag loading with 5 wt% confirms the minimization of the bandgap from 3.6 down to 2.57 eV with enhanced visible light absorption and sustaining the magnetic *** Ag/NiCo2O4nanorods showed a superior photodegradation of ATZ within 20 min at2.0 g L-1with excellent *** enhancement of the photocatalytic activity is referred to the local surface plasmon resonance of Ag-loaded *** reduces the electron-hole recombination and outperforms the unloaded *** work is highlighting the application of magnetically separable spinel photocatalysts for the removal of herbicides and water remediation.

关键词： Spinel photocatalyst Visible light Photodegradation Atrazine Magnetic separation

Controlled drainage in the Nile River delta of Egypt:a promising approach for decreasing drainage off-site effects and enhancing yield and water use efficiency of wheat

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Journal of Arid Land 2023年第4期15卷 460-476页

作者： mohamed K EL-GHANNAM Fatma WASSAR Sabah MORSY mohamed HAFEZ Chiter M PARIHAR Kent O BURKEY ahmed M abdallah Soil Water and Environment Research InstituteAgricultural Research CenterGiza 12112Egypt Higher Institute of Water Sciences and Techniques of Gabès University of GabèsGabès 6072Tunisia Institute of Arid Regions Medenine 4119Tunisia Crop Science Department Faculty of AgricultureDamanhour UniversityDamanhour 22516Egypt Land and Water Technologies Department Arid Lands Cultivation Research InstituteCity of Scientific Research and Technological ApplicationsNew Borg El-Arab 21934Egypt Indian Council of Agricultural Research(ICAR)-Indian Agricultural Research Institute(IARI) New Delhi 110012India United States Department of Agriculture(USDA)-Agricultural Research Services(ARS) Plant Science Research UnitNorth Carolina 27607USA Natural Resources and Agricultural Engineering Department Faculty of AgricultureDamanhour UniversityDamanhour 22516Egypt

North Africa is one of the most regions impacted by water *** implementation of controlled drainage(CD)in the northern Nile River delta of Egypt is one strategy to decrease irrigation,thus alleviating the negative impact of water *** study investigated the impacts of CD at different levels on drainage outflow,water table level,nitrate loss,grain yield,and water use efficiency(WUE)of various wheat *** levels of CD,i.e.,0.4 m below the soil surface(CD-0.4)and 0.8 m below the soil surface(CD-0.8),were compared with subsurface free drainage(SFD)at 1.2 m below the soil surface(SFD-1.2).Under each drainage treatment,four wheat cultivars were grown for two growing seasons(November 2018–April 2019 and November 2019–April 2020).Compared with SFD-1.2,CD-0.4 and CD-0.8 decreased irrigation water by 42.0%and 19.9%,drainage outflow by 40.3%and 27.3%,and nitrate loss by 35.3%and 20.8%,*** CD treatments,plants absorbed a significant portion of their evapotranspiration from shallow groundwater(22.0%and 8.0%for CD-0.4 and CD-0.8,respectively).All wheat cultivars positively responded to CD treatments,and the highest grain yield and straw yield were obtained under CD-0.4 *** the initial soil salinity as a reference,the soil salinity under CD-0.4 treatment increased two-fold by the end of the second growing season without negative impacts on wheat *** the drainage system by raising the outlet elevation and considering shallow groundwater contribution to crop evapotranspiration promoted water-saving and *** responses could be obtained based on the different plant tolerance to salinity and water stress,crop characteristics,and growth ***-specific soil salinity management practices will be required to avoid soil salinization due to the adoption of long-term shallow groundwater in Egypt and other similar agroecosystems.

关键词： drainage ratio nitrate loss water use efficiency yield soil salinity Nile River delta

Evaluation of antidiabetic activity of plants used in Western Sudan

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Asian Pacific Journal of Tropical Biomedicine 2015年第5期5卷 395-402页

作者： maha Abdulrahman Alamin ahmed Ibrahim Yagi Sakina mohamed Yagi Botany Department Faculty of Science University of Khartoum Department of Pharmacology and Toxicology College of Pharmacy King Saud University Department of Biological Science and Chemistry University of Nizwa

Objective: To investigate the traditional antidiabetic uses of some indigenous Sudanese plants on streptozotocin-induced diabetes rats. Methods: Diabetic rats were treated with a 400 mg/kg dose of aqueous extracts of five plant species orally for 2 h(acute) or 14 days(chronic). In acute model blood glucose levels were monitored at specific intervals. In the chronic model blood samples were collected from overnight fasted diabetic rats on day 15 to estimate blood glucose level. And the body weight, serum lipid profile and activities of liver and kidney enzymes were measured. Histopathological observations of liver sections were also ***: In the case of acute treatment, aqueous extracts of Tinospora bakis(T. bakis), Nauclea latifolia(N. latifolia) and Randia nilotica(R. nilotica) at 400 mg/kg significantly lowered(P < 0.05) blood glucose levels in diabetic rats whereas, chronic treatment of diabetic rats with 400 mg/kg of T. bakis, N. latifolia, R. nilotica and Mitragyna inremis proved to have significant(P < 0.05) antihyperglycemic effect and have the capacity to correct the metabolic disturbances associated with diabetes. Histopathological studies showed that the aqueous extracts of these four plants reinforced the healing of liver. However, Striga hermonthica aqueous extract did not exert any antihyperglycemic effect to diabetic rats. Conclusions: This study demonstrated that T. bakis, N. latifolia, R. nilotica and Mitragyna inremis have therapeutic value in diabetes and related complications and thus supporting the traditional uses of these plants in Sudanese traditional medicine.

关键词： Tinospora bakis Mitragyna inremis Nauclea latifolia Randia nilotica Striga hermonthica Antihyperglycemic effect

The Role of Humic Acid and Proline on Growth, Chemical Constituents and Yield Quantity and Quality of Three Flax Cultivars Grown under Saline Soil Conditions

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Agricultural Sciences 2014年第14期5卷 1566-1575页

作者： Bakry ahmed Bakry Moamen Hamed Taha Zainab ahmed Abdelgawad maha mohamed Shater abdallah Field Crops Department National Research Centre Dokki Egypt Agronomy Department Faculty of Agriculture Cairo University Giza Egypt Botany Departments Women’s College Ain Shams University Cairo Egypt Botany Departments National Research Centre Dokki Egypt

In order to mitigate the salinity effects on flax grown on moderate saline sandy soil (3275 - 3430 ppm) and irrigated with moderate saline water (2300 - 2460 ppm) field experiments were carried out at the experimental Station of the Faculty of Agriculture, Wadi El-Natrun district El-Behera Governorate—Egypt, during two successive winter seasons of 2012/2013 and 2013/2014. Three flax varieties (Opal, Giza-8 and Mayic) were grown and treated with some chemical additives humic acid (50 kg/fed) and/or foliar applied proline (Control, 50 and 100 mg/L). The results showed the positive responses of Giza-8 variety to the combined application of humic acid and proline and mitigated the salinity effects of soil and irrigation water and reflected on most of the studied characters. Such results indicate the potentiality of mitigation the hazardous effect of salinity with these chemical additives. The data indicated that the highest seed yield, straw yield and oil yield were obtained at humic acid (50 kg/fed) with foliar treatment of proline at rate of (100 mg/L). The interaction of proline at (100 mg/L) with humic acid at rate of (50 kg/fed) improved plant fresh and dry weight in all flax cultivars under salinity conditions. Fresh weight increased by 66.6%, 48.7% and 65.5% over controls for Opal, Giza-8 and Mayic varieties, respectively. The interaction of proline at (100 mg/L) with humic acid at rate of (50 kg/fed) with Giza-8 variety gave the highest values of seed yield, straw yield and oil yield.

关键词： Flax Humic Acid Proline Seed and Oil Yield