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Amination of biochar surface from watermelon peel for toxic chromium removal enhancement

Chinese Journal of Chemical Engineering 2021年第8期34卷 199-222页

作者： mohamed A.el-Nemr Ibrahim M.A.Ismail Nabil M.Abdelmonem Ahmed el Nemr Safaa Ragab Department of Chemical Engineering Faculty of EngineeringCairo UniversityGizaEgypt Renewable Energy Program Zewail City of Science and TechnologyEgypt Environmental Division National Institute of Oceanography and FisheriesKayet BeyEl-AnfoushyAlexandriaEgypt

Watermelon peel residues were used to produce a new biochar by dehydration *** new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI)ions from aqueous solution has been *** biochars,Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA,were made from watermelon peel via dehydration with 50%sulfuric acid to give Melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give Melon-BO-NH_(2) or Triethylenetetramine(TETA)to give *** prepared biochars were characterized by BET,BJH,SEM,FT-IR,TGA,DSC and EDAX *** highest removal percentage of Cr(VI)ions was 69%for Melon-B,98%for Melon-BO-NH_(2) and 99%for Melon-BO-TETA biochars of 100 mg·L^(−1) Cr(VI)ions initial concentration and 1.0 g·L^(−1) adsorbents *** unmodified biochar(Melon-B)and modified biochars(Melon-BO-NH_(2) and Melon-BO-TETA)had maximum adsorption capacities(Q_(m))of 72.46,123.46,and 333.33 mg·g^(−1),*** amination of biochar reduced the pore size of modified biochar,whereas the surface area was *** obtained data of isotherm models were tested using different error function *** Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA,*** adsorption rate was primarily controlled by pseudo-second–order rate ***,the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption *** adsorption for the Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction.

关键词： Waste treatment Powder technology Citrullus lanatus Hexavalent chromium Biochar amination Adsorption

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Enhancing mechanical behaviors of collapsible soil using two biopolymers

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 329-339页

作者： mohamed Ayeldeen Abdelazim Negm Mostafa el-Sawwaf Masaki Kitazume Structural Engineering Department Tanta UniversityTantaEgypt Faculty of Engineering Zagazig UniversityZagazigEgypt Civil and Environmental Engineering Department Tokyo Institute of TechnologyTokyoJapan

This study aims to investigate the possibility of using biopolymer(environmental friendly material) to enhance the mechanical behaviors of collapsible *** types of biopolymers were(xanthan gum and guar gum) used in this study due to their stable behaviors under severe conditions and their availability with reasonable *** experimental program focused on three major soil properties,*** characterizations,collapsible potential and shear *** three properties are essential in process of soil *** biopolymer concentrations were used in this study and the experimental program was performed at two curing periods(soon after mixing the soil with the biopolymer and after one week curing time).Shear parameters were measured for the treated specimens under both soaked and unsoaked conditions,while a collapsible potential test was performed under different mixing conditions(wet mix and dry mix).A numerical model was built to predict the behavior of the treated collapsible soil after and before water *** results indicated that the ability of both xanthan gum and guar gum can be used as improvement materials for collapsible soil *** collapsible potential has been reduced from 9%to 1%after mixing the soil with 2%biopolymer concentration in the wet *** one week curing,the cohesion has been increased from 8.5 kPa to105 kPa by increasing the xanthan gum concentration from zero to 2%,leading to an overall improvement in soil shear *** also proves that the guar gum is superior to the xanthan *** shear strength of soil can be increased by about 30%when using the guar gum in comparison with the xanthan gum at the same conditions;however,the collapsible potential of soil material will be reduced by about 20%.

关键词： Collapsing soil Xanthan gum Guar gum Collapsible potential Shear strength Compaction characterizations Numerical model

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Epidemiological and clinical characteristics of inflammatory bowel diseases in Cairo,Egypt

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World Journal of Gastroenterology 2014年第3期20卷 814-821页

作者： Serag Esmat mohamed el Nady mohamed elfekki Yehia elsherif Mazen Naga Division of Gastroenterology Department of Internal MedicineFaculty of MedicineCairo University Department of Internal Medicine Faculty of MedicineBeni Suef University Department of Tropical Medicine Faculty of MedicineCairo University

AIM: To study the natural history, patterns and clinical characteristics of inflammatory bowel diseases (IBD) in Egypt.

关键词： Natural history of Inflammatory bowel diseases, Epidemiology of Ulcerative colitis, Epidemiology of Crohn’ s disease, Epidemiology of inflammatory bowel diseases in Egypt, inflammatory bowel diseases Prevalence, Incidence of ulcerative colitis, Incidence of Crohn’ s disease

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Filtered High Gain Observer for an electric Vehicle’s electro-hydraulic Brake: Design and Optimization Using Multivariable Newton-based Extremum Seeking

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Chinese Journal of electrical Engineering 2023年第4期9卷 73-87页

作者： Jamal el-bakkouri Hamid Ouadi Fouad Giri mohamed Khafallah ENSEM Hassan II University of CasablancaCasablanca BP 8118Morocco ENSAM Rabat Mohammed V UniversityRabat BP 6207Morocco Department of electrical Engineering University of Caen NormandyCaen 14032France

Designing high-gain observers(HGOs)for the state estimation of an electric vehicle’s electrohydraulic brake(EHB)system is *** type of observer is applicable to model nonlinearities and constant feature ***,they are very sensitive to measurement noise,which is unavoidable in *** first novelty of this study is that it compensates for the measurement noise using a filtered high-gain observer(FHGO)to ensure EHB state *** proposed FHGO provides an estimate of the master cylinder pressure,motor current,and rotor speed from measurements of the rotor *** second novelty is the design of an extremum-seeking(ES)optimization loop to adjust the FHGO gains *** performance of the developed FHGO with ES-based online gain optimization was highlighted in the presence of model uncertainties and output measurement noise using a Matlab/Simulink *** superiority of the FHGO(even with a fixed gain)over a standard high gain observer(SHGO)was also demonstrated.

关键词： electrohydraulic brake filtered HGO measurement noise optimization extremum-seeking Lyapunov theory

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A case of portal vein thrombosis associated with acute cholecystitis/pancreatitis or coincidence

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Hepatobiliary & Pancreatic Diseases International 2006年第2期5卷 308-310页

作者： mohamed el-Wahsh London Bridge Hospital 27 Tooley Street London SE1 2PRUnited Kingdom

BACKGROUND: Portal vein thrombosis (PVT) is complex and risk factors include local precipitating factors and acquired and inherited factors. It occurs secondary to abdominal malignancy, infection or surgical intervention. PVT is commonly forgotten as a possible cause of abdominal pain. The clinical picture may vary but abdominal pain and low grade fever are the most characteristic picture. METHODS: A 58-year-old male patient was admitted to our hospital complaining of abdominal pain for three days. CT scan revealed an edematous area around the portal vein. Doppler ultrasonography showed evidence of a portal vein thrombosis. RESULTS: PVT can be diagnosed with CT and Doppler ultrasonography. Fresh thrombus can be undetected by sonography because of the low echogenity but can be recognised by color Doppler ultrasonography. Treatment ranges from observation and bowel rest to surgical resection of bowel. CONCLUSIONS: When we suspect a case of PVT, it should be treated at an early stage to prevent being lost in a diagnostic dilemma. The immediate use of anticoagulant could be important in preventing serious consequences of PVT.

关键词： portal vein thrombosis hypercoagulation enoxaparin cavernomatous transformation

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Generation of sodium hypochlorite (NaOCl) from sodium chloride solution using C/PbO_2 and Pb/PbO_2 electrodes

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 561-566页

作者： Nasser Abu Ghalwa Hassan Tamos mohamed elAskalni Abed Rhman el Agha Chemistry Department Al-Azhar University of GazaP.O.Box 1277Palestine

Two modified electrodes （Pb/PbO2 and C/PbO2） were prepared by electrodepositing a lead oxide layer on lead and carbon sub- strates. These modified electrodes were used as anodes for the generation of sodium hypochlorite （NaOC1） from sodium chloride solution. Different operating conditions and factors affecting the treatment process of NaOC1 generation, including current density, pH values, con- ductive electrolytes, and electrolysis time, were studied and optimized. By comparison the C/PbO2 electrode shows a higher efficiency than the Pb/PbO2 electrode for the generation of NaOC1.

关键词： sodium hypochlorite sodium chloride lead oxide electrodeposition electrodes

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Strength and Wear Behavior of Mg Alloy AE42 Reinforced with Carbon Short Fibers

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 31-40页

作者： Sabbah Ataya Naser A.Alsaleh mohamed M.el-Sayed Seleman Metallurgical and Materials Engineering Department Faculty of Petroleum and Mining Engineering Suez University Department of Mechanical Engineering College of Engineering Al Imam Mohammad Ibn Saud University

In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it necessary to assess their wear performance. Little research data have been discussed on wear behavior of Mg alloy AE42 matrix and its composites. Thus, this paper reports wear behavior of magnesium alloy AE42(Mg–Al–Mn—RE; rare earth) and its composite AE42-C, which contains 23 vol% of randomly oriented carbon short fibers. Materials characterization, including density measurements, hardness testing, microstructures investigation, and compression testing at temperatures of 25, 150,and 300 °C, were conducted. Wear tests were performed under various loads and sliding distances. Wear mechanisms were also proposed based on the examination of worn surfaces using optical microscopy and scanning electron microscopy equipped with EDX(energy-dispersive X-ray spectrometry) analysis system. The hardness of AE42-23 vol% C composite is twice the hardness of the Mg matrix alloy AE42. Significant improvements to yield stress and compressive strength at temperatures of 25, 150, and 300 °C of the composite versus the AE42 alloy are achieved. Wear resistance of the composite is improved considerably versus that of the Mg alloy AE42 at the various sliding distances. Smearing of graphite on the worn surface produces a lubricating film that delays change from mild to severe wear of the composite, especially at high loads. EDX analysis of the worn surface shows oxidation of the matrix alloy at higher wear loads, and this mechanism decreases in the presence of carbon fibers under the same loads. Abrasive wear, oxidation, and plastic deformation are the dominant wear mechanisms for the alloy matrix AE42, whereas mainly abrasive wear is the wear mechanism of AE42-23 vol% C composite under the proposed testing conditions.

关键词： Magnesium composites Carbon short fibers Compressive strength Wear resistance Wear mechanisms

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A Multi-Level Threshold Method for Edge Detection and Segmentation Based on Entropy

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Computers, Materials & Continua 2020年第4期63卷 1-16页

作者： mohamed A.el-Sayed Abdelmgeid A.Ali mohamed E.Hussien Hameda A.Sennary Department of Mathematics Faculty of ScienceFayoum UniversityFayoumEgypt.CurrentlyComputer Science DepartmentTaif UniversityTaifSaudi Arabia Computer Science Department Faculty of Computers and Information Minia UniversityMiniaEgypt Department of Mathematics Faculty of ScienceAswan UniversityAswanEgypt

The essential tool in image processing,computer vision and machine vision is edge detection,especially in the fields of feature extraction and feature *** is a basic area in information *** entropy,in image processing field has a role associated with image *** an initial step in image processing,the entropy is always used the image’s segmentation to determine the regions of image which is used to separate the background and objects in *** segmentation known as the process which divides the image into multiple regions or sets of *** applications have been development to enhance the image *** paper utilizes the Shannon entropy to achieve edge detection process and segmentation of the *** introduces a new method of edge detection for 2-D histogram and Shannon entropy based on multilevel *** method utilizes the gray value and the average gray value of the pixels to achieve the two dimensional *** current method has apriority in comparison to some upper classical *** experimental results exhibited that the proposed method could capture a moderate quality and execution time better than other comparative methods,particularly in the largest images *** proposed method offers good results when applied with images of different sizes from the civilization of ancient Egyptians.

关键词： Multi-level threshold edge detection 2D histogram entropy

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Genetic Variability and Phenotypic Correlations Study among Grain Quality Traits and Mineral elements Concentrations in Colored and Non-Colored Rice (Oryza sativa L.)

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1733-1748页

作者： Adel A.Rezk mohamed M.el-Malky Heba I.mohamed Hossam S.el-Beltagi Agricultural Biotechnology Department College of Agricultural and Food ScienceKing Faisal UniversityAl-Ahsa31982Saudi Arabia Plant Pathology Research Institute Agriculture Research CenterGiza12619Egypt Rice Research and Training Center Field Crop Research InstituteAgriculture Research Center33717Egypt Biological and Geological Sciences Department Faculty of EducationAin Shams UniversityCairo11511Egypt Biochemistry Department Faculty of AgricultureCairo UniversityGiza12613Egypt

Twenty-four rice genotypes were examined to assess genetic variability,heritability,and correlations for seven-grain quality traits,eight nutritional elements,and *** revealed signiﬁcant differences for the quality traits *** every trait under study,the phenotypic coefﬁcient of variation was higher than the correspon-dence genotypic coefﬁcient of *** in a broad sense varied from 29.75%for grain length to 98.31%for the elongation *** percentage recovery had a highly signiﬁcant positive correlation with milling and head rice ***,milling percentage had a highly positive correlation with head rice *** amylose percentage,all the genotypes belonged to low amylose except the Hassawi-1 variety,which had intermediate amylose *** nutrition contents of magnesium(Mg),sodium(Na),potas-sium(K),calcium(Ca),copper(Cu),manganese(Mn),zinc(Zn),iron(Fe),or protein percentage gave different variations for 24 rice genotypes under all the nutritional *** the 24 genotypes,ten rice genotypes–HighNutrient-1,HighNutrient-2,HighNutrient-9,HighNutrient-8,HighNutrient-3,Hassawi-2,HighNutrient-7,HighNutrient-6,Hassawi-1,and HighNutrient-4–had the highest heist value for all nutritional and protein con-tents,and could be used as a donor to improving new *** was a positive and signiﬁcant correlation between magnesium Mg,K,Zn and ***,K had a positive correlation with zinc Zn,Fe,and protein *** analysis was divided into two groups:theﬁrst group included all genotypes rich in nutri-ents,while the remaining genotypes with low nutritional content were included in the second group.

关键词： Amylose cluster analysis genotypes grain quality mineral nutrition rice

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Prediction of COVID-19 Transmission in the United States Using Google Search Trends

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Computers, Materials & Continua 2022年第4期71卷 1751-1768页

作者： Meshrif Alruily mohamed Ezz Ayman mohamed Mostafa Nacim Yanes Mostafa Abbas Yasser el-Manzalawy College of Computer and Information Sciences Jouf UniversitySakaka72314Saudi Arabia Faculty of Engineering Al-Azhar UniversityCairo11651Egypt Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt RIADI Laboratory La Manouba UniversityManouba2010Tunisia Department of Translational Data Science and Informatics GeisingerDanvillePA17822USA

Accurate forecasting of emerging infectious diseases can guide public health officials in making appropriate decisions related to the allocation of public health *** to the exponential spread of the COVID-19 infection worldwide,several computational models for forecasting the transmission and mortality rates of COVID-19 have been proposed in the *** accelerate scientific and public health insights into the spread and impact of COVID-19,Google released the Google COVID-19 search trends symptoms open-access *** objective is to develop 7 and 14-day-ahead forecasting models of COVID-19 transmission and mortality in the US using the Google search trends for COVID-19 related ***,we propose a stacked long short-term memory(SLSTM)architecture for predicting COVID-19 confirmed and death cases using historical time series data combined with auxiliary time series data from the Google COVID-19 search trends symptoms *** the SLSTM networks trained using historical data only as the base models,our base models for 7 and 14-day-ahead forecasting of COVID cases had the mean absolute percentage error(MAPE)values of 6.6%and 8.8%,*** the other side,our proposed models had improved MAPE values of 3.2%and 5.6%,*** 7 and 14-day-ahead forecasting of COVID-19 deaths,the MAPE values of the base models were 4.8%and 11.4%,while the improved MAPE values of our proposed models were 4.7%and 7.8%,*** found that the Google search trends for“pneumonia,”“shortness of breath,”and“fever”are the most informative search trends for predicting COVID-19 *** also found that the search trends for“hypoxia”and“fever”were the most informative trends for forecasting COVID-19 mortality.

关键词： Forecasting COVID-19 transmission and mortality in the US stacked LSTM SARS-COV-2 and google COVID-19 search trends

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