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Isotherm and kinetic studies on the adsorption of humic acid molecular size fractions onto clay minerals

Acta Geochimica 2019年第6期38卷 863-871页

作者： mohamed E.A.El-Sayed moustafa m.r.khalaf James A.rice Department of Chemistry and Biochemistry South Dakota State UniversityBrookingsSD 57007USA Soils Waterand Environmental Research InstituteAgriculture Research CenterEl-GizaEgypt Chemistry Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt

Humic acid(HA)can adsorb onto mineral surfaces,modifying the physicochemical properties of the ***,understanding the sorption behavior of HA onto mineral surfaces is of particular interest,since the fate and transport of many organic and inorganic contaminants are highly correlated to HA adsorbed onto clay *** to the extreme heterogeneity of HA,the extracted IHSS Leonardite humic acid(LHA)used in this work was fractionated using an ultrafiltration technique(UF)into different molecular size fractions(Fr1,>0.2μm;Fr2,0.2 pm-300,000 daltons;Fr3,300,000-50,000 daltons;Fr4,50,000-10,000 daltons;Fr5,10,000-1000 daltons).Equilibrium and the kinetics of LHA and fraction adsorption onto kaolinite and montmorillonite were *** results demonstrated that the maximum adsorption capacity of LHA,Frl,Fr2,Fr3,Fr4,and Fr5 was 5.99,13.69,10.29,7.02,5.9&and 5.09 on kaolinite while it was 8.29,22.62,13.17,8.91,8.62,and 5.69 on montmorillonite,*** adsorption equilibrium data showed that the adsorption behavior of LHA and its fractions could be described more practically by the Langmuir model than the Freundlich *** rate of humic acid fraction adsorption onto clays increased with decreasing molecular size fraction and increasing carboxylic group ***-first-and second-order models were used to assess the kinetic data and the rate *** results explained that LHA and its fractions adsorption on clay minerals conformed more to pseudosecondo rder.

关键词： Kaolinite montmorillonite Leonardite humic acid Humic acid fractions Kinetics Equilibrium

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自组装和化学成分对腐植酸矿化影响的比较

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腐植酸 2015年第5期 29-40页

作者： moustafa m.r.khalaf Gabriela Chilom James A.rice 张水勤袁亮美国南达科塔州立大学化学与生物化学系布鲁金斯sd57007 埃及米尼亚大学理学院化学系米尼亚61519 中国农业科学院农业资源与农业区划研究所北京100081

为了定量评估有机质自组装对其抗微生物矿化作用的影响,从风化褐煤、2种泥炭和1种矿质土壤中分离出的腐植酸用作有机质样品,因为其在来源和有机成分性质方面具有广泛的可变性。以苯-甲醇为提取剂,将原始的腐植酸样品分解成为腐植酸组分... 详细信息

为了定量评估有机质自组装对其抗微生物矿化作用的影响,从风化褐煤、2种泥炭和1种矿质土壤中分离出的腐植酸用作有机质样品,因为其在来源和有机成分性质方面具有广泛的可变性。以苯-甲醇为提取剂,将原始的腐植酸样品分解成为腐植酸组分和腐植酸-脂质复合物,用碱溶液从腐植酸-脂质复合物中进一步提取出两性腐植酸组分和脂质组分。根据以上各组分在腐植酸中的准确比例,混合各自固体组分,制成与自组装样品化学成分一致的物理混合物。添加原始的腐植酸及其相应的混合物作为唯一的碳源,使用矿质土壤中分离出的微生物菌群开展独立的有氧培养试验。矿化培养125天后,自组装样品矿化量比相应的物理混合物高70%。13C固态核磁共振光谱所得的碳类型分布和疏水性指数结果表明,自组装样品的矿化程度与其化学成分不相关。物理混合物和组分的矿化程度因化学成分而不同,且存在着烷基碳优先矿化的现象。以上研究结果表明,腐植酸的微生物矿化与其自组装程度有关。

关键词：土壤有机质腐植酸自组装矿化热容量核磁共振量热法

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Simulation of a molten salt fast reactor using the COmSOL multiphysics software

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Nuclear Science and Techniques 2020年第12期31卷 1-19页

作者： D.H.Daher m.Kotb A.m.khalaf moustafa S.El-Koliel Abdelfattah Y.Soliman Department of Physics Faculty of ScienceAl-Azhar UniversityCairoEgypt Department of reactors Nuclear Research CenterAtomic Energy AuthorityCairoEgypt Nuclear Engineering Department King Abdulaziz UniversityJeddahSaudi Arabia

In this study,COmSOL v5.2 multiphysics software was utilized to perform coupled neutronics and thermal–hydraulics simulations of a molten salt fast reactor,and the SCALE v6.1 code package was utilized to generate the homogenized cross-section data *** library’s 238 cross-section groups were categorized into nine groups for the simulations in this *** results of the COmSOL model under no fuel flow conditions were verified using the SCALE v6.1 code results,and the results of the neutronics and thermal–hydraulics simulations were compared to the results of previously published *** results indicated that the COmSOL model that includes the cross-section library generated by the SCALE v6.1 code package is suitable for the steady-state analysis and design assessment of molten salt fast ***,this model was utilized to investigate the neutronics and thermal–hydraulics behaviors of the *** designs were simulated and analyzed in this model,and the results indicated that even if the wall of the core is curved,hot spots occur in the upper and lower portions of the core’s center near the reflectors.A new design was proposed that utilizes a flow rate distribution system,and the simulation results of this design showed that the maximum temperature in the core was approximately 1032 K and no hot spots occurred.

关键词： molten salt COmSOL SCALE Neutronics Thermal-hydraulic

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Wrap choice during fundoplication

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World Journal of Gastroenterology 2019年第48期25卷 6876-6879页

作者： Simon r Bramhall moustafa m mourad Department of Surgery The County HospitalHereford HR12ERUnited Kingdom Department of Surgery Worcester Royal InfirmaryWorcester WR51DDUnited Kingdom

Gastro-oesphageal reflux disease is an increasing health *** mainstay of treatment has conventionally been medical therapy but since the introduction of laparoscopic surgery laparoscopic anti-reflux surgery has been increasingly used for intractable symptoms or in patients unwilling to take long term *** Nissen 360 degree wrap has traditionally been considered the gold standard operation but can be associated with significant *** complications include“gas bloat”and dysphagia and can occur relatively *** modifications have been described to the original operation and some of these have been *** addition alternative wraps have been described which seem to have a reduced incidence of complications associated with their *** editorial discusses the various types of wrap that can be performed and the minimum requirements of the surgical *** evidence from a recent meta-analysis of the randomised data has suggested that an anterior wrap is associated with a lower rate of complications and gives just as good control of reflux *** advantages and disadvantages of an anterior wrap are *** lack of long term follow up data concerns some practitioners and at the moment the choice of wrap carried out still rests with the individual surgeon.

关键词： Fundoplication Wrap Laparoscopic reflux disease Choice

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Treating wastewater under zero waste principle using wetland mesocosms

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 155-168页

作者： Safaa m.Ezzat mohammed T.moustafa microbiology Deptartment Central Laboratory for Environmental Quality Monitoring(CLEQM)National Water Research Center(NWRC)CairoEgypt

The present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating *** system was designed to support a horizontal surface flow pattern and showed satisfactory removal efficiencies for both physicochemical and bacteriological contaminants within 3 days of residence *** removal efficiencies ranged between 76.3%and 98.8%for total suspended solids,turbidity,iron,biological oxygen demand,and *** bacterial indicators(total and fecal coliforms,as well as fecal streptococci)and the potential pathogens(Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa)showed removal efficiencies ranged between 96.9%and 99.8%.We expect the system to offer a smart management for every component according to zero waste *** treated effluent was reused to irrigate the landscape of pilot area,and the excess sludge was recycled as fertilizer and soil *** zeolite mineral did not require regeneration for almost 36 weeks of operation,and enhanced the density of shoots(14.11%)and the height of shoots(15.88%).The harvested plant biomass could be a profitable resource for potent antibacterial and antioxidant bioactive *** could certainly offset part of the operation and maintenance costs and optimize the system implementation *** the experiment was designed under local conditions,its results could provide insights to upgrade and optimize the performance of other analogous large-scale constructed wetlands.

关键词： Wastewater Dynamic roughing filter Cyperus papyrus(L.) Zeolite Zero waste

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Geotectonic significance of the Neoproterozoic ophiolitic metagabbros of muiswirab area,South Eastern Desert,Egypt:constraints from their mineralogical and geochemical characteristics

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Acta Geochimica 2020年第6期39卷 887-910页

作者： moustafa m.mogahed Wlaa mahmoud Saad Geology Department Faculty of ScienceBenha University-EgyptP.O.Box 13518BenhaEgypt

Petrological and geochemical studies of Neo-proterozoic metagabbros were carried out in the muiswirab area,South Eastern Desert of *** muiswirab area comprises of ophiolitic metagabbroic rocks(mOm),which are tectonically thrusted over a thick pile of metavolcanic rocks and intruded by syn-and post-tectonic granitoid *** whole-rock geochemical variations coupled with chemical compositions of mineral constituents are used to attain the genesis and tectonic evolution of the studied *** geothermobarometric investiga-tion of the analyzed amphiboles from(mOm)revealed that these metagabbros underwent regional metamorphism under lower to upper greenschist facies(biotite zone)conditions(at a temperature of 450 to 500℃and pressure of 1-3 kbar).Geochemically,the metagabbros(mOm)show tholeiitic affinity and cxhibiting both arc-and mOrB-like characters as evidenced by their clinopyrox-ene compositions and the Ti/V ratios(11.84-31.65),which considered as prominent features of forearc tectonic *** geochemical features suggest a probable fractionation of olivine±clinopyroxene±plagioclase as well as insignificant crustal *** parental magma of the investigated mOm rocks seems to be developed in a sub-arc mantle wedge setting due to the enrichments of LILE(e.g..rb,Ba,Sr,Pb)over HFSE(e.g,Ti,Nb,Y,Zr,Hf,Ta).The studied mOm rocks have lower values of Nb/U relative to mOrB and OIB indicating that their geochemical variation produced due to the enrichment of a lithosphere mantle by OIB like *** ratios of Zn/Fet,La/Sm,Sm/Yb,Th/Yb and Nb/Yb indicate that the mOm rocks represent a fragment of oceanic crust originated at a supra-subduction zone environment and their parental magma developed by 5-30%partial melting of a spinel lherzolite mantle rather than pyroxenite in an island arc setting and conformable with most of the Egyptian ophiolitic metagabbros.

关键词： Egypt Eastern Desert muiswirab area Ophiolitic metagabbros N-mOrB Arc tholeiites Foreare tectonic regime Volcanic-arc setting

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Constraints of mantle and Crustal Sources Interaction during Orogenesis of Pre-and Post-collision Granitoids from the Northern Arabian-Nubian Shield:A Case Study from Wadi El-Akhder Granitoids,Southern Sinai,Egypt

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1527-1550页

作者： moustafa m.mOGAHED Khaled m.ABDELFADIL Geology Department Faculty of ScienceBenha UniversityBenha 13518Egypt Geology Department Faculty of ScienceSohag UniversitySohag 82524Egypt

The Egyptian older and younger granitic rocks emplaced during pre-and post-collision stages of Neoproterozoic Pan-African orogeny,respectively,are widely distributed in the southern Sinai Peninsula,constituting 70% of the basement *** Wadi El-Akhder,southwestern Sinai,is a mountainous terrain exposing two granitoid suites,namely the Wadi El-Akhder Older Granites(AOG)and the Homra Younger Granites(HYG).The AOG(granodiorites with subordinate tonalite compositions)have geochemical characteristics of medium-K calc-alkaline,metaluminous to mildly peraluminous granitoids formed in an island-arc environment,which are conformable with well-known Egyptian older granitoids rocks,whereas the HYG display calc-alkaline to slightly alkaline nature,peraluminous syeno-,monzogranites and alkali feldspar granites matching well those of the Egyptian younger *** respect to the AOG granitoids,the HYG granites contain lower Al_(2)O_(3),FeO^(*),mgO,mnO,CaO,TiO_(2),Sr,Ba,and V,but higher Na_(2)O,K_(2)O,Nb,Zr,Th,and *** AOG are generally characterized by enrichment in LILE and LrEE and depletion in HFSE relative to N-mOrB values(e.g.,negative Nb and Ta anomalies).The geochemical features of the AOG follow assimilation-fractional crystallization(AFC)trends indicative of extensive crustal contamination of magma derived from a mantle *** chemical characteristics of the AOG are remarkably similar to those of subduction-related granitoids from the ArabianNubian Shield(ANS).The compositional variations from monzogranites through syenogranites to alkali feldspar granite within HYG could not be explained by fractional crystallization *** the whole-rock composition of the HYG to melts generated by experimental dehydration melting of meta-sedimentary and magmatic rocks reveals that they appear to be derived by extended melting of psammitic and pelitic metasediments,which is similar to the most of younger granitic suites in the ANS.

关键词： older and younger granitoids mantle-crust interaction assimilation-fractional crystallization(AFC) southern Sinai Arabian-Nubian Shield

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Framework for COVID-19 Segmentation and Classification Based on Deep Learning of Computed Tomography Lung Images

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Journal of Electronic Science and Technology 2022年第3期20卷 246-256页

作者： Wessam m.Salama moustafa H.Aly the Department of Basic Science Faculty of EngineeringPharos UniversityAlexandria12455Egypt the Department of Electronics and Communications Engineering College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportAlexandria1029Egypt

Corona Virus Disease 2019(COVID-19) has affected millions of people worldwide and caused more than6.3 million deaths(World Health Organization, June 2022). Increased attempts have been made to develop deep learning methods to diagnose COVID-19 based on computed tomography(CT) lung images. It is a challenge to reproduce and obtain the CT lung data, because it is not publicly available. This paper introduces a new generalized framework to segment and classify CT images and determine whether a patient is tested positive or negative for COVID-19 based on lung CT images. In this work, many different strategies are explored for the classification ***50 and VGG16 models are applied to classify CT lung images into COVID-19 positive or negative. Also,VGG16 and reNet50 combined with U-Net, which is one of the most used architectures in deep learning for image segmentation, are employed to segment CT lung images before the classifying process to increase system performance. moreover, the image size dependent normalization technique(ISDNT) and Wiener filter are utilized as the preprocessing techniques to enhance images and noise suppression. Additionally, transfer learning and data augmentation techniques are performed to solve the problem of COVID-19 CT lung images deficiency, therefore the over-fitting of deep models can be avoided. The proposed frameworks, which comprised of end-to-end, VGG16,resNet50, and U-Net with VGG16 or resNet50, are applied on the dataset that is sourced from COVID-19 lung CT images in Kaggle. The classification results show that using the preprocessed CT lung images as the input for U-Net hybrid with resNet50 achieves the best performance. The proposed classification model achieves the 98.98%accuracy(ACC), 98.87% area under the rOC curve(AUC), 98.89% sensitivity(Se), 97.99 % precision(Pr), 97.88%F-score, and 1.8974-seconds computational time.

关键词： Augmentation classification computed tomography(CT) Corona Virus Disease 2019(COVID-19) deep learning resNet50 segmentation U-Net VGG16

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Deterministic and Stochastic Fractional Order model for Lesser Date moth

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Computer Systems Science & Engineering 2022年第2期40卷 749-764页

作者： moustafa El-shahed Asmaa m.Al-Dububan Department of mathematics Unaizah College of Sciences and ArtsQassim UniversityP.O.Box 3771Unaizah51911Saudi Arabia Department of mathematics Buraydah College of Sciences and ArtsQassim UniversityP.O.Box 1162Buraydah51431Saudi Arabia

In this paper,a deterministic and stochastic fractional order model for lesser date moth(LDm)using mating disruption and natural enemies is proposed and *** interaction between LDm larvae,fertilized LDm female,unfertilized LDm female,LDm male and the natural enemy is *** order to clarify the characteristics of the proposed deterministic fractional order model,the analysis of existence,uniqueness,non-negativity and boundedness of the solutions of the proposed fractional-order model are *** addition,some sufficient conditions are obtained to ensure the local and global stability of equilibrium *** occurrence of local bifurcation near the equilibrium points is investigated with the help of Sotomayor’s *** simulations are conducted to illustrate the properties of the proposed fractional order model with respect to the intrinsic growth rate of the LDm larvae,natural enemy’s mortality rate,predation rate,sex pheromone trap parameter,fractional order and environmental *** impact of mating disruption on lesser date moth is ***,a numerical approximation method is developed for the proposed stochastic fractional-order model.

关键词： Lesser date moth stochastic stability natural enemies Sotomayor’s theorem mating disruption

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Energy Staggering in Ground Bands of ^(232)Th and ^(236,238)U Nuclei Using the Interacting Vector Boson model

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Communications in Theoretical Physics 2015年第7期64卷 90-94页

作者： A.m.khalaf m.m.Sirag m.Kotb Physics Department Faculty of Science Al-Azhar University Physics Department Faculty of Girls Ain Shams University

The△I = 2 and △I = 4 staggering parameters of transition energies Eγfor normally deformed positive parity ground bands in232 Th and236,238 U nuclei are studied in framework of the symplectic extension of the interacting vector boson model. The model parameters are obtained from the fitting procedure between the calculated excitation energies and the corresponding experimental ones. The staggering parameters represent the finite difference approximations to higher order derivatives dnEγ/d Inof the γ-ray transition energies in a△I = 2 and △I = 4 bands, which yielding multipoint formulae. The first order derivative(two-point formula) provides us with information about the dynamical moment of inertia. The staggering oscillation for the fourth order derivative(five-point formula) is about 0.5 Ke V and is even larger than that in superdeformed bands. The quite similarity in dynamical moments of inertia of the isotopes236,238 U up to high spin states indicate that the phenomenon of identical bands is not restricted to superdeformed bands.

关键词： staggering interacting vector Boson model moment o

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