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Effect of phosphoric acid concentration on conductivity of anodic passive film formed on surface of lead-indium alloy

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Transactions of Nonferrous Metals society of China 2016年第3期26卷 882-894页

作者： Abdel-Rahman el-sayed Hossnia.s.MOHRAN hoda Abdel shafy sHILKAMY Department of Chemistry Faculty of Science Sohag UniversitySohag 82524Egypt

The addition of phosphoric acid into sulfuric acid solution is mentioned to be helpful in the reduction of sulfation after deep discharge of lead-acid battery. The anodic behavior of Pb and Pb?In alloys was studied in pure phosphoric acid and sulfuric acid containing various concentrations of phosphoric. The electrochemical measurements were performed using potentiodynamic, potentiostatic and cyclic voltammetric techniques. The composition and morphology of passive layer formed on the surfaces of Pb and Pb?In alloys were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy analysis (EDX) and scanning electron microscopy (sEM). The potentiodynamic study shows that the passive current density increases with increasing the indium content in the alloy in the examined solutions. The addition of 0.1 mol/L H3PO4 into theelectrolyte is more effective to decrease the thickness of passive film on the surface of alloys containing higher indium content (10% and 15%). The XRD, EDX and sEM data reveal that the formation of PbsO4 and PbO on the surface decreases with increasing the indium level in the alloy and is completely prevented at higher indium content (15%) in mixed acid.

关键词： lead-indium alloy phosphoric acid anodic behavior passive film lead-acid batteries

The Impact of Inoculum Preparation Media on Pollutant Removal through Phycoremediation of Agricultural Drainage Water by Desmodesmus sp.

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Phyton-International Journal of Experimental Botany 2023年第10期92卷 2875-2890页

作者： Asmaa salah hoda sany Abo el-Khair B.el-sayed Reham M.el-Bahbohy Heba I.Mohamed Ayman Amin Plant Physiology Division Department of Agricultural BotanyFaculty of AgricultureCairo UniversityGizaP.O.Box 12613Egypt Algal Biotechnology Unit National Research CentreDokkiGiza12622Egypt Biological and Geological science Department Faculty of EducationAin Shams UniversityCairo11341Egypt

Water is the most essential natural resource for the future *** production is extensively water-dependent and a significant polluter of water ***,this work investigated the effect of two different preparation media[Bold’s Basal Medium(BBM)and Domiati cheese whey(DCW)]for agricultural drainage water(ADW)*** treatments were incubated for 6 *** to the results of biomass productivity,specific growth rate,photosynthetic pigments,and biochemical composition,Desmodesmus *** grow in drainage water without *** two treatments significantly reduced the concentration of nitrate,phosphate,chemical oxygen demand,and sodium in ***,using cheese whey with BBM as inoculum preparation media enhanced the lipid accumulation in the algal biomass(25.4%w/w)and gave the best biodiesel properties among ***,combining remediation of drainage water with microalgae mass production can achieve the sustainability of agriculture.

关键词： Desmodesmus sp. drainage water nutrients recycle photosynthetic pigments phycoremediation water scarcity

Egyptian heavy vacuum gas oil hydrotreating over Co-Mo/CNT and Co-Mo/γ-Al2O3 catalysts

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燃料化学学报 2016年第7期44卷 853-861页

作者： W.Ahmed hoda,s.Ahmed H.s.el-sheshtawy Nadia,A.Mohamed Asmaa,I.Zahran Egyptian Petroleum Research Institute 1Aahmed El-Zomor st.Naser city 11727CairoEgypt Ain-shams University for Girls Roqqsy SquireCairoEgypt

The catalytic activity of CoMos /CNT towards the Egyptian heavy vacuum gas oil hydrotreating was studied. The delivered CNT was functionalized with 6 mol /L HNO_3. The CNT were loaded with 12% MoO_3( by weight) and 0.7 Co /Mo atomic ratio with impregnation methods. The γ-Al_2O_3 catalyst was also prepared by impregnation method to compare both catalysts *** analysis tools such XRD,Raman spectroscopy,TEM,and BET were used to characterize the catalysts. The autoclave reactor was used to operate the hydrotreating experiments. The hydrotreating reactions were tested at various operating conditions of temperature 325-375 ℃,pressure 2-6 MPa,time 2-6 h,and catalyst /oil ratio( by weight) of 1 ∶75,1 ∶33 and 1 ∶10. The results revealed that the CoMos /CNT was highly efficient for the hydrotreating more than the CoMos /γ-Al_2O_3. Also, the hydrodesulfurization( HDs) increased with increasing catalyst /oil ratio. Additionally,results showed that the optimum condition was temperature 350℃,pressure 4 MPa,catalyst /oil ratio of 1 ∶75 for 2 h. Furthermore,even at low CoMos /CNT catalyst /oil ratio of 1 ∶75,an acceptable HDs of 77.1% was achieved.

关键词： hydrotreatment hydrodesulfurization carbon nanotube heavy vacuum gas oil(HVGO)

Parameters Affecting Energy Consumption for Producing High Carbon Ferromanganese in a Closed submerged Arc Furnace

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Journal of Iron and steel Research International 2014年第7期21卷 666-672页

作者： Azza Ahmed Hossam Halfa Mohamed K.el-Fawakhry hoda el-Faramawy Mamdouh Eissa steel Technology Metallurgical Research and Development Institute

The power consumption is considered to be the most important factor affecting the production cost of fer romanganese alloy. Different parameters affecting the energy consumption for industrial production of high carbon ferromanganese HCFeMn were investigated in a closed submerged arc furnace. The analysis of industrial data revealed that the most energy consumed factors were the direct reduction by solid carbon, Boudouard reaction, metal and slag formation, and decomposition of fluxing materials （limestone and dolomite）. To reduce the energy con- sumption and minimize the energy losses in the production process of HCFeMn, it was recommended to use Mn blend with minimum Mn to Fe ratio of 6 and lower siO2 content or higher basicity. The added coke must be adjusted according to the material balance to prevent the over-coke and to minimize the highly endothermic ＂Boudouard reac tion＂. In addition, it was recommended to work at basic slags with the ratio of （CaO＋MgO） to si（）2 equal to 1.0- 1.2 instead of much higher slag basicity. Furthermore, the mass losses had to be minimized through adjusting the handling and charging process and to take care of all metal produced.

关键词： high carbon ferromanganese production energy consumption carbonate decomposition Boudouard reaction slag basicity energy loss

suitability of sDN and MEC to facilitate digital twin communication over LTE-A

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Digital Communications and Networks 2024年第2期10卷 347-354页

作者： Hikmat Adhami Mohammad Alja’afreh Mohamed hoda Jiaqi Zhao Yong Zhou Abdulmotaleb el saddik Mohamed bin Zayed University of Artificial Intelligence Masdar CityAbu DhabiUnited Arab Emirates school of Computer science and Technology China University of Mining and TechnologyXuzhou221116China school of electrical Engineering and Computer science University of OttawaOttawaONK1N 6N5Canada

Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control *** will require ultra-low latency and ultra-high reliability to evolve the mobile experience into the era of Digital Twin and Tactile *** the 5th generation of mobile networks is not yet widely deployed,Long-Term Evolution(LTE-A)latency remains much higher than the 1 ms requirement for the Tactile Internet and therefore the Digital *** work investigates an interesting solution based on the incorporation of software-defined networking(sDN)and Multi-access Mobile Edge Computing(MEC)technologies in an LTE-A network,to deliver future multimedia applications over the Tactile Internet while overcoming the Qos *** network scenarios were designed and simulated using Riverbed modeler and the performance was evaluated using several time-related Key Performance Indicators(KPIs)such as throughput,End-2-End(E2E)delay,and *** best scenario possible is clearly the one integrating MEC and sDN approaches,where the overall delay,jitter,and throughput for haptics-attained 2 ms,0.01 ms,and 1000 packets per *** results obtained give clear evidence that the integration of,both sDN and MEC,in LTE-A indicates performance improvement,and fulfills the standard requirements in terms of the above KPIs,for realizing a Digital Twin/Tactile Internet-based system.

关键词： LTE-A 5G Digital twin Tactile Internet KPIs sDN MEC NFV Haptic

Effect of cooling rate and composition on microstructure and mechanical properties of ultrahigh-strength steels

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Journal of Iron and steel Research International 2019年第12期26卷 1350-1365页

作者： Mohammed Ali David Porter Jukka Komi Mamdouh Eissa hoda el Faramawy Taha Mattar Materials and Mechanical Engineering Centre for Advanced Steels ResearchUniversity of OuluOulu 90014Finland steel Technology Department Central Metallurgical Research and Development InstituteHelwanCairo 11421Egypt

The influence of cooling rate on the microstructure and mechanical properties of two new ultrahigh-strength steels(UHsss)with different levels of C,Cr and Ni has been evaluated for the as-cooled and untempered *** UHss had higher contents of C and Cr,while the other one had a higher Ni *** the basis of dilatation curves,microstructures,macrohardness and microhardness,continuous cooling transformation diagrams were constructed as a guide to heat treatment *** rates(CRs)of 60,1 and 0.01°C/s were selected for more detailed *** characterization was made by laser scanning confocal microscopy,field emission scanning electron microscopy combined with electron backscatter diffraction,electron probe microanalysis and X-ray *** properties were characterized using macrohardness,tensile and Charpy V-notch impact *** with the higher C and Cr contents showed lower transformation temperatures and slower bainite formation kinetics than that with the higher Ni *** cooling rates led to lower volume fractions and carbon contents of retained austenite together with finer prior austenite grain size,as well as effective final grain size and lath *** changes were accompanied by higher yield and tensile *** best combinations of strength and toughness were obtained with martensitic microstructures and by avoiding the formation of granular bainite accompanied by proeutectoid carbides at low *** the cooling rates studied,UHss with the higher C and Cr contents showed the higher hardness and strength but at the cost of toughness.

关键词： Ultrahigh-strength steel electroslag remelting Continuous cooling transformation diagram Microstructure feature Mechanical property

Health problems among street children seeking care in the Center for social and Preventive Medicine in Egypt

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World Journal of Pediatrics 2017年第5期13卷 503-507页

作者： hoda Ibrahim Rizk Nihal Mohamed el Rifai Hana Mohamed Aboulghar Public Health and Community Medicine Department Faculty of MedicineCairo UniversityCairoEgypt Pediatrics Department Faculty of MedicineCairo UniversityCairoEgypt

Background:In Egypt,around 1 million children are on the *** children's health is an issue that is not well *** objective of the current study was to determine the health problems of a targeted group of street children seeking medical care and to generate a hypothesis about the positive/negative role of street children care ***:A cross-sectional study was done on 2169 street children who sought medical care at el-Basma clinic at the Center for social and Preventive Medicine in Cairo University Children Hospital from January 2011 to July ***:Respiratory illnesses and skin problems were the most prevalent conditions,affecting 485 (22.4%) and 359 (16.6%) of the patients,*** issues and trauma were significantly higher among the adolescent *** and gastrointestinal problems were significantly higher among children aged less than 2 *** and cardiac problems were significantly higher among those referred from organizations whereas trauma was significantly higher among those coming directly from the streets.A significant proportion of children at the extremes of the studied age spectrum were coming directly from the *** transmitted infections were rare ***:Respiratory and skin diseases were the major morbidity problems among street children,especially adolescent *** afforded opportunities for access to different health care services.

关键词： Egypt health problems street children

Associations between CD133,CK19 and G2/M in cirrhotic HCV(genotype-4)patients with or without accompanying tumor

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BIOCelL 2018年第2期42卷 55-60页

作者： hoda M.el-EMsHATY Entsar A.sAAD Mona s.GOUIDA Zahraa R.elsHAHAWY Gastroenterology surgical Center Faculty of MedicineMansoura UniversityEgypt Chemistry Department Faculty of ScienceDamietta UniversityDamiettaEgypt Mansoura Children Hospital Faculty of MedicineMansoura UniversityEgypt

Hepatitis C virus(HCV)-cirrhotic patients have the highest threat of developing hepatocellular carcinoma(HCC)and may be at risk of extra hepatic *** present study was designed to investigate CD133 and CK19 in HCV(genotype-4)-cirrhotic patients with/without HCC or extra hepatic cancer,to assess the degree of their correlation with cell cycle abnormalities and finally to assess the role of their combination as diagnostic tool for discrimination of cirrhotic patients with HCC from those with extra hepatic *** study included 77 HCV-cirrhotic patients and 20 healthy non-disease control *** were categorized histo-pathologically into:24 have only liver cirrhosis,26 with HCC,and 27 patients with extra hepatic *** cycle abnormalities,CD133 and CK19 were determined by flow cytometry ***133 and CK19 showed marked elevation in HCC and extra hepatic cancer compared with liver cirrhosis and control subjects(psitive associations were noted between CK19,CD133 and G2/*** were gradually increased with progression from liver cirrhosis to *** of the three showed the best AUC(0.978)and accuracy(92.5%)for discrimination of HCC from extra hepatic *** CD133 with G2/M and CK19 comprises an excellent diagnostic panel for discrimination of HCV-cirrhotic patients with HCC from those with extra hepatic cancer.

关键词： Cell cycle Diagnostic performance Liver Panel

Adaptive Interval Type-2 Fuzzy Controller for Variable-speed Wind Turbine

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Journal of Modern Power systems and Clean Energy 2022年第2期10卷 524-530页

作者： Danyal Bustan hoda Moodi Quchan University of Technology QuchanIran

In this paper,an adaptive interval type-2 fuzzy controller is proposed for variable-speed and variable-pitch wind *** of attractive features of the well-known wind turbine baseline controller,the proposed controller acts as an augmented controller and works in parallel to the baseline *** typical variable-speed wind turbines have different controllers for different operation regions,for each operation region,a dedicated interval tvpe-2 fuzzy controller is *** of the uncertainty in wind speed measurement,modern control techniques try to estimate this ***,in contrast to these modern control techniques,the proposed controller is independent of the wind speed ***,there is a better saving in cost and computational *** evaluate the effectiveness of the proposed controller,simulations are conducted with wind profiles which span all operation *** show that,compared with the baseline controller,the proposed controller enhances power generations and reduces mechanical loads concurrently.

关键词： Interval type-2 fuzzy control baseline controller wind speed measurement wind turbine