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Assessment of coal gasification in a pressurized fixed bed gasifier using an ASPEN plus and Euler–Euler model

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International Journal of Coal Science & Technology 2020年第3期7卷 516-535页

作者： Tamer M.Ismail Mingliang Shi Jianliang Xu Xueli Chen Fuchen Wang M.abd El-salam Mechanical Engineering Department Suez Canal UniversityIsmailiaEgypt Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education East China University of Science and TechnologyShanghaiChina Shanghai Engineering Research Center of Coal Gasification East China University of Science and TechnologyShanghaiChina Department of Basic Science Cairo UniversityGizaEgypt

With the help of Aspen Plus,a two-dimensional unsteady CFD model is developed to simulate the coal gasification process in a fixed bed gasifier.A developed and validated two dimensional CFD model for coal gasification has been used to predict and assess the viability of the syngas generation from coal gasification employing the updraft fixed bed *** process rate model and the sub-model of gas generation are *** particle size variation and char burning during gasification are also taken into *** order to verify the model and increase the understanding of gasification characteristics,a set of experiments and numerical comparisons have been carried *** simulated results in the bed are used to predict the composition of syngas and the conversion of *** model proposed in this paper is a promising tool for simulating the coal gasification process in a fixed bed gasifier.

关键词： Fixed bed gasifier Aspen plus Euler-Euler model Coal

Effect of Al_(2)O_(3) Nanoparticles on the Compression Ignition Performances and Emitted Pollutants of a Diesel Engine

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Fluid Dynamics & Materials Processing 2023年第11期19卷 2847-2861页

作者： Noora S.Ekab Ahmed Q.salam Ali O.abd Miqdam T.Chaichan Electromechanical Engineering Department University of Technology-IraqBaghdad65035Iraq Environment Research Center University of Technology-IraqBaghdad65035Iraq Applied Science Department University of Technology-IraqBaghdad65035Iraq Energy and Renewable Energies Technology Center University of Technology-IraqBaghdad65035Iraq

To improve the performances of diesel engines and to reduce the pollutants they emit,aluminum oxide nanopar-ticles in varying quantities(50,100,150 ppm)have been added to conventional diesel *** results of such experimental tests have revealed that the addition of nano-Al_(2)O_(3) particles to the diesel fuel reduces its consump-tion by 0.488%,1.02%,and 1.377%,respectively and increases the brake thermal efficiency by 1.4%,2.6%,and 3.8%,*** concentrations of undesired gases decrease accordingly by 1.5%,1.7%,and 2.8%for HC and by 5.88%,11.7%,and 17.6%,respectively,for *** the same percentages of nanoparticles,NO_(x) increases by 2.65,4.36,and 5.37,while the TSP(Total Suspended Particulate)decreases by 22%,34.66%,and 49.7%,*** the same conditions,sulfur dioxide pollutants increase by 4.57%,8.8%and 12.89%,and H_(2)S levels by 4.7%,7.81%and 8.9%,respectively.

关键词： Nao-Al_(2)O_(3) suspension CO NO_(x)-PM trade-off SO_(2) H_(2)

Biochemical changes in phenols,flavonoids,tannins,vitamin E,β-carotene and antioxidant activity during soaking of three white sorghum varieties

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Asian Pacific Journal of Tropical Biomedicine 2012年第3期2卷 203-209页

作者： abd El-Moneim MR Afify Hossam S El-Beltagi Samiha M abd El-salam Azza A Omran Department of Biochemistry Faculty of AgricultureCairo University Department of Crops Technology Food Technology Research InstituteAgricultural Research CenterEgypt

Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum ***: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were ***:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado *** ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in *** the other hand,protocatechuic acid represents the major phenolic acids in *** flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and ***,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking.

关键词： Sorghum Soaking Total phenols Flavonoids Tannins Vitamin E β-carotene Antioxidant activity Phenolic acids Flavonoid components Biochemical change

Different Methods of Analysis for the Identification of Materials Dated to Different Periods in Egypt

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Journal of Physical Science and Application 2011年第2期1卷 85-99页

作者： Safaa abd El salam Department of Painting Faculty of Fine Arts Conservation of Mural Painting University of Alexandria 108 Abd El Salam Aref Alex. Egypt

Different questions may be raised during the course of analysis concerning in particular the characterization of materials used, their preparation and application techniques. The different methods used to identify the materials of mud brick, limestone, plaster, mortar and pigments, collected from different sites and periods from Egypt, in order to identify and characterize the materials, their structure, composition and their mineralogical compounds were：（Op） optical microscopy, which was used to examine and to identify the materials structures. Methods used in initial examination were：（1）（MCA）： Micro-chemical analysis, to identify the nature of the materials and for water-soluble salts, to identify sulphates, chlorides, carbonates, nitrites and nitrates; （2）（SM）： Standard methods of wet chemical analysis were used to identify the quantitative and qualitative nature of the, mud building, mortars and their mixtures; （3）（SEM ＆ EDS）： Analytical scanning electron microscope with energy dispersive X-ray analysis system was used to examine the micro-morphology and determine the chemical composition of the different materials; （4）（XRD ＆ XRPD）： X-ray diffraction to identify the mineralogical compound of the plaster, limestone, mortars and pigments used. From all the results obtained, it was possible to establish the nature of the mortars and their binders as well as some other inclusion. In addition to the identification of the stratigraphy of the layers applied in some samples, the examination and analysis gave details of the materials and the approximate ratio of the amount of additives used. Furthermore, the mineralogical analysis provided information on the main mineralogical phases present in the materials analyzed from the different periods.

关键词： Characterization different materials chemical and physical methods.

Numerical and experimental analysis for simulating fuel reactor in chemical looping combustor system

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International Journal of Coal Science & Technology 2020年第3期7卷 551-559页

作者： Tamer M.Ismail Lu Ding Khaled Ramzy Mabd El-salam Department of Mechanical Engineering Suez Canal UniversityIsmailiaEgypt Institute of Clean Coal Technology East China University of Science and TechnologyShanghai200237China Department of Basic Science Cairo UniversityGizaEgypt

The greenhouse problem has a significant effect on our communities such as,health and *** dioxide is one of the main gases that cause global ***,CO2 capture techniques have been the focus of attention these *** chemical looping combustion technique adopted the air reactor and fuel reactor to recycle heat *** study presents a numerical and experimental investigation on a fuel reactor in chemical looping combustor(CLC)*** present numerical model is introduced by the kinetic theory of granular flow and coupled with gas–solid flow with chemical reactions to simulate the combustion of solids in the *** k–εturbulent model was used to model the gas phase and the particle *** developed model simplify the prediction of flow patterns,particle velocities,gas velocities,and composition profiles of gas products and the distribution of heterogeneous reaction rates under the same operating *** predicted and experimental results were compared according to the basis of determination coefficient(R2).In addition the results showed that there is a good agreement between the predicted and experimental *** value of(R2)for CO,CO2 and CH4 was 0.959,0.925 and 0.969 *** shows that the present model is a promising simulation for solid particle combustion and gives the power direction for the design and optimization of the CLC systems.

关键词： Chemical looping combustion Mathematical modeling Fluidized bed Coal Kinetic model

Binding Media： Methods of Identification： Part 1, Theoretical Work

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Journal of Physical Science and Application 2011年第3期1卷 204-215页

作者： Safaa Ahmed abd El salam Faculty of Fine Arts University of Alexandria 108 Abd El Salam Aref Egypt

The identification of binding media presents a major difficulty in the investigation of painting techniques. The materials used in ancient times as a media for the pigments were varied, such as glues, gums and egg white. These adhesives were mixed with the pigments to adhere to the surface or to prepare the ground. This medium serves to protect the pigments more or less perfectly, from chemical and mechanical injury. Binding media determines the technique of painting. Artists＇ techniques used through the centuries differ more in the binding media than in the pigments used. They are all organic substances containing the same common elements, and in the small samples which can be removed from paintings, occur only in micro quantities, moreover, binding media undergo considerable degradation over long periods of time. In the examination of works of art, only very small specimens can be taken and, the proportion of binding medium to pigment being small, sensitive methods of analysis have to be adopted in an attempt to detect and identify the medium that may have been used. On the other hand, the use of such methods possesses the disadvantage that impurities present in the painting materials may also be detected and may lead to erroneous conclusions. There is no general microanalysis technique existed in the identification of binding media, and the materials commonly used as media are highly complex compared with the simple inorganic compounds employed as pigments. However, several methods can be used in the identification of binding media such as micro-chemical, chemical and physical methods.

关键词： Painting media chemical & physical methods

Vegetation productivity responses to drought on tribal lands in the four corners region of the Southwest USA

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Frontiers of Earth Science 2018年第1期12卷 37-51页

作者： Mohamed abd salam EL-VILALY Kamel DIDAN Stuart E. MARSH Willem J.D. VAN LEEUWEN Michael A. CRIMMINS Armando Barreto MUNOZ The Intemational Food Policy Research Institute Washington DC 20006-1002 USA Vegetation Index and Phenology Lab Department of Agricultural and Biosystems Engineering The University of Arizona Tucson AZ 85721-0036 USA Arizona Remote Sensing Center School of Natural Resources and the Environment The University of Arizona Tucson AZ 85721-0043 USA Department of Soils Water and Environmental Science The University of Arizona Tucson AZ 85721-0038 USA

For more than a decade, the Four Comers Region has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources while exacerbating soil erosion. These persistent droughts threaten ecosystem services, agriculture, and livestock activities, and expose the hypersensitivity of this region to inter-annual climate variability and change. Much of the intermountain Western United States has sparse climate and vegetation monitoring stations, making fine-scale drought assessments difficult. Remote sensing data offers the opportunity to assess the impacts of the recent droughts on vegetation productivity across these areas. Here, we propose a drought assessment approach that integrates climate and topographical data with remote sensing vegetation index time series. Multisensor Normalized Difference Vegetation Index （NDVI） time series data from 1989 to 2010 at 5.6 km were analyzed to characterize the vegetation productivity changes and responses to the ongoing drought. A multi-linear regression was applied to metrics of vegetation productivity derived from the NDVI time series to detect vegetation productivity, an ecosystem service proxy, and changes. The results show that around 60.13% of the study area is observing a general decline of greenness （p 〈 0.05）, while 3.87% show an unexpected green up, with the remaining areas showing no consistent change. Vegetation in the area show a significant positive correlation with elevation and precipitation gradients. These results, while, confirming the region＇s vegetation decline due to drought, shed further light on the future directions and challenges to the region＇s already stressed ecosystems. Whereas the results provide additional insights into this isolated and vulnerable region, the drought assessment approach used in this study may be adapted for application in other regions where surfacebased climate and vegetation monitoring record is spatially and temporally limited.

关键词： drought remote sensing Hopi Navajo Nation

Anisotropy of Magnetic Susceptibility (AMS) of Bostonite Rocks, Um-Gir and El-Atshan-II Uranium Prospect Areas, Central Eastern Desert, Egypt

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Geomaterials 2022年第1期12卷 1-14页

作者： Hussein F. abd El-salam Nuclear Materials Authority El Maadi Cairo Egypt

Um-Gir and El-Atshan-II areas represent important structurally-controlled radioactive anomalies and have become promising areas for U exploration. The bostonite rocks represent the most promising rock unit in the two studied areas. They form the most promising rocks due to their high radioactivity and, hence uranium mineralization. Anisotropy of magnetic susceptibility (AMS) measurements was carried out for Um-Gir and El-Atshan-II bostonite rocks. The AMS results show that the mean magnitude of magnetic susceptibilities is low, of the order of 10-5 S.I. units. Consequently, the bostonite rocks of the two areas are considered as non-magnetic, reflecting the presence of hematite as the main ferromagnetic mineral. These results are in agreement with the measurements of initial remnant magnetization (NRM) and the results of isothermal remnant magnetization (IRM) for the two areas. Besides, the results of magnetic anisotropy degree (PJ), refer to and concluded that the magnetic fabric of bostonite of two the areas has secondary fabric. AMS results clearly show the differences between the bostonite dyke of Um-Gir and Bostonite sill of El Atshan-II. The lineation (P1) > foliation (P3), and the negative values of the ellipsoid shape (T) of Um-Gir bostonite reflect clearly magnetic lineation (prolate ellipsoid). However, in El Atshan-II, (P3 > P1), the values of T are positive, which indicate the predominance of magnetic foliation (oblate ellipsoid) over lineation. Furthermore, the foliation planes of the bostonite dyke of Um-Gir possess a shallow to moderate inclination and a nearly N-S direction, while, the foliation planes of the bostonite sill of El-Atshan-II show a shallow to moderate inclination and a NNE direction. Finally, the AMS method is a powerful tool for detecting the structures that affect

关键词： Central Eastern Desert Egypt Bostonite Rocks AMS NRM IRM

Formulation of the Post-Newtonian Equations of Motion of the Restricted Three Body Problem

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Applied Mathematics 2011年第2期2卷 155-164页

作者： Fawzy A. abd El-salam Sobhy abd El-Bar 不详

In the present work the geodesic equation represents the equations of motion of the particles along the geodesics is derived. The deviation of the curved space-time metric tensor from that of the Minkowski tensor is considered as a perturbation. The quantities is expanded in powers of c-2. The equations of motion of the relativistic three body problem in the PN formalism are obtained.

关键词： Post Newtonian Approximation Geodesic Equation Restricted Three Body Problem