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effect of Some Heterocyclic derivatives on the Removal of Copper Ions from Wastewater by Cementation

Journal of Materials Science & Technology 2004年第5期20卷 539-546页

作者： A.A.Taha M.G.Marei d.e.abd el-khalek department of Chemistry Faculty of ScienceUniversity of AlexandriaAlexandriaEgyptDepartment of ChemistryFaculty of ScienceUniversity of AlexandriaAlexandriaEgyptDepartment of ChemistryFaculty of ScienceUniversity of AlexandriaAlexandriaEgypt

Removal of copper ions from copper sulphate solutions on a rotating zinc rod in absence and in presence of 3(2H)-furanones and 4H-pyran-4-one derivatives was investigated experimentally. Variables studied were initial copper ions concentration, rotational speed of the zinc rod, temperature and concentration of organic additives. It was found that cementation reaction is first order in presence and in absence of additives. Increasing concentration of initial copper ions, rotational speed of the zinc rod and temperature were found to increase the rate of cementation. In presence of organic additives an enhancement of the rate was observed, except in presence of methoxyfuranone the rate was found to decrease by an amount ranging from 11.74% to 33.79%. Rate acceleration or inhibition is associated mainly with changes in the structure of the additives as well as its concentration. The apparent activation energy for the cementation process in presence of different additives was estimated and was found to be ranged between 11.8 kJ/mol and 25.95 kJ/mol. These values suggest that the copper removal process in presence of these additives is controlled by diffusion. A scanning electron microscopy study of copper deposits obtained in presence of tolylfuranone, phenylpyrone and methoxyfuranone correlate with their behaviour during the kinetic study. different reaction conditions and the physical properties of solutions were studied to obtain dimensionless correlation among all these parameters. It was found that on applying cementation reaction on a sample from industrial wastewater in presence of phenylpyrone about 91.9% of Cu2+ are removed.

关键词： Cementation of copper Furanone and pyrone derivatives

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effect of different metal sulfate precursors on structural and catalytic performance of zirconia in dehydration of methanol to dimethyl ether

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燃料化学学报 2018年第1期46卷 67-74页

作者： abd el-Aziz A.Said Mohamed abd el-Aal Chemistry department Faculty of ScienceAssiut University71516 AssiutEgypt

ZrO_2 was treated with 10% SO_4^(2-) from different metal sulfate precursors for methanol dehydration to dimethyl *** the samples exhibited tetragonal phase and no diffraction peaks corresponding to metal sulfates or metal oxides were *** FT-IR results revealed that there were different interactions between sulfate and ZrO_2,and this had a great effect on the surface area of the *** catalytic activity was measured over the catalysts in the temperature range of 100-300 ℃.The results revealed that sulfated zirconia with CuSO_4·5 H_2O and Al_2(SO_4)_3·16 H_2O showed the best catalytic *** maximum yield of dMe ≈87% was obtained over CuSZ at a reaction temperature of 275 ℃.Moreover,the catalytic activity of the catalysts was correlated well with their surface acidity that measured by dehydration of isopropanol.

关键词： MSO 4/ZrO2 甲醇脱水 dMe

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effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： M.H.abd-el Salam S.el-Gamal M.Mohsen d.M.abd el-Maqsoud Physics department Faculty of Education Ain Shams University Physics department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PdMS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （dSC）. Tm and the degree of crystallinity （χc） of PdMS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PdMS loaded with different contents of filler has been studied. Mullins ratio （RM） was found to be dependent on the filler type and content. It was found that, RM increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. Moreover, the hysteresis in PdMS-CB composites was more pronounced than in PdMS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PdMS composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

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Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

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Journal of Central South University 2017年第9期24卷 2049-2057页

作者： Ramadan Noha Ahmed Hossameldin H el-khamy Said.e.abd el-Samie Fathi e Faculty of electronic engineering Menofia University Faculty of engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

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A Robust Tuned Random Forest Classifier Using Randomized Grid Search to Predict Coronary Artery diseases

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Computers, Materials & Continua 2023年第5期75卷 4633-4648页

作者： Sameh abd el-Ghany A.A.abd el-Aziz department of Information Systems College of Computer and Information SciencesJouf UniversityKSA department of Information Systems Faculty of Computers and InformationMansoura UniversityEgypt department of Information Systems and Technology Faculty of Graduate Studies for Statistical ResearchCairo UniversityEgypt

Coronary artery disease(CAd)is one of themost authentic cardiovascular afflictions because it is an uncommonly overwhelming heart *** breakdown of coronary cardiovascular disease is one of the principal sources of death all over *** deterioration is a challenge,especially in youthful and rural countries where there is an absence of humantrained *** heart diseases happen without apparent signs,high-level detection is *** paper proposed a robust and tuned random forest model using the randomized grid search technique to *** proposed framework increases the ability of CAdpredictions by tracking down risk pointers and learning the confusing joint efforts between ***,the healthcare industry has a lot of data but needs to gain more *** proposed framework is used for extracting knowledge from data stores and using that knowledge to help doctors accurately and effectively diagnose heart disease(Hd).We evaluated the proposed framework over two public databases,Cleveland and Framingham *** datasets were preprocessed by using a cleaning technique,a normalization technique,and an outlier detection ***,the principal component analysis(PCA)algorithm was utilized to lessen the feature dimensionality of the two ***,we used a hyperparameter tuning technique,randomized grid search,to tune a random forest(RF)machine learning(ML)*** randomized grid search selected the best parameters and got the ideal CAd *** proposed framework was evaluated and compared with traditional *** proposed framework’s accuracy,sensitivity,precision,specificity,and f1-score were 100%.The evaluation of the proposed framework showed that it is an unrivaled perceptive outcome with tuning as opposed to other ongoing existing frameworks.

关键词： Coronary artery disease tuned random forest randomized grid search classifier

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Wear properties of copper and copper composites powders consolidated by high-pressure torsion

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Friction 2020年第2期8卷 433-450页

作者： Mohamed Ibrahim abd el AAL Mechanical engineering department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addawaser 11991Saudi Arabia Mechanical design&Production department Faculty of EngineeringZagazig UniversityZagazig 44519Egypt

The wear characteristics of Cu and Cu-SiC composite microsize powders consolidated by cold compaction combined with sintering or high-pressure torsion(HPT)were *** HPT processed(HPTed)samples with bimodal and trimodal microstructures and fine Cu grains and SiC particle sizes have superior hardness,reasonable ductility level,and high wear *** wear mass loss and coefficient of friction of HPTed samples were remarkably lower than that of cold-compacted and sintered samples as well as that of micro and nano Cu and Cu-SiC composites from previous *** sample fabrication method has an apparent influence on the wear *** wear mechanism was converted from adhesive,delamination,three-body mechanism,grooves(take off the SiC particles),and cracks into abrasive wear after *** can be considered a dominant wear mechanism in all *** worn surface morphology and analysis support the relationship between wear mechanism and characteristics.

关键词： Cu-SiC composite powders high-pressure torsion(HPT) fine and coarse grains wear characteristics worn surface morphology

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How elevation and soil properties affect plant distribution patterns and species diversity in the Mediterranean mountain ecosystem of Al-Jabal Al- Akhdar, Libya

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Journal of Mountain Science 2024年第11期21卷 3683-3701页

作者： abd el-GHANI Monier AL BORKI abd el-Nasser department of Botany and Microbiology Faculty of ScienceCairo UniversityGiza 12613Egypt department of Biology Faculty of EducationUniversity of BenghaziBenghaziLibya

The objectives of this study were to assess distribution patterns of plant species richness,plant diversity and vegetation structure in relation to environmental factors along elevation gradient in Al-Jabal Al-Akhdar,*** each species,its growth form,chorological affinities,degree of occurrence,endemism status and originality were provided.A total of 534 taxa were generated from 70 families of the flowering plants,and 3 of the non-flowering plants were *** native flora of the study area was counted for 80.2%of the total indigenous taxa(465).The hump-shaped pattern of plant species richness was obtained,with the highest species richness at the mid-elevations,and both ends of the gradient have the *** annuals(300 species,56.2%)and non-succulent perennial herbs(165 species,30.9%)were the most dominant growth forms of the total species *** the elevation gradient,Asteraceae,Fabaceae,Poaceae,Lamiaceae and Apiaceae were the dominant families with the highest numbers of *** investigation recorded 31 endemic taxa,comprising 25 dicots and 6 monocots,primarily of Mediterranean origin,with most belonging to the Asteraceae and Lamiaceae *** chorotype was the dominant,whether pure(mono-),or combined with one(bi-and pluri-regional)or more(pluri-regional).Application of cluster analysis on the vegetation data yielded four cluster groups;each was linked to an elevation *** emphasized the importance of establishing conservation strategies to minimize human disturbance and safeguard relic habitats of Juniperus phoenicea *** its southern distribution limits in Africa,underlining the proactive management required for species *** application of Redundancy Analysis revealed that Shannon diversity index(H'),pH and Fe were the determinant soil factor in the mid-elevation levels(L2 and L3)whereas altitude,fine sand,HCO3,OM,and soil contents of Na,SO4 and Cl for the extreme levels(L1 and L4).

关键词： Altitudinal gradient distribution patterns Floristic diversity Growth forms Libya Soil structure Vegetation analysis

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Ore Controls and Metallogenesis of Au-Ag deposits at Atalla Mine,Central eastern desert of egypt

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Acta Geologica Sinica(english edition) 2020年第5期94卷 1451-1470页

作者： Mohamed abd el MONSeF Geology department Faculty of ScienceTanta UniversityTanta 31527Egypt Institute of Geological Sciences Faculty of ScienceMasaryk UniversityBrnoCzech Republic

Gold-silver deposits in the Atalla area occur as hydrothermal quartz veins in Ne–SW pre-existing fractures within the Atalla granitic *** orientation of such quartz veins has been attributed to extensional behavior related to the Atalla Shear Zone(ASZ).The Atalla area is covered by a variety of lithologies that are(from oldest to youngest):metasedimentary rocks,metavolcanic rocks,ophiolite assemblage(serpentinites/talc-carbonates),Atalla granite and dokhan volcanic ***,Atalla granite ranges in composition from granodiorite to *** geochemistry constrains the calc-alkaine affinity of the Atalla granite that was intruded within an orogenic(syncollision)tectonic *** ore minerals are represented by gold/silver(electrum),pyrite(Py1&Py2),arsenopyrite,pyrrhotite,sphalerite,chalcopyrite,galena,covellite and *** temperature of ore formation ranges from 240 to 285℃and the estimated fluid pressure is in the range of 20–100 *** on the geological setting,ore textures and fluid characteristics;the Atalla Au-Ag deposits are considered to be orogenic in nature,formed from a continental collision(~653-590 Ma),synchronous with the emplacement of calc-alkaline magmatism during the evolutionary history of the Arabian Nubian Shield(ANS).The initial ore-forming fluid was primarily derived from a metamorphic source related to ophiolitic-serpentinite rocks under deep regional conditions of greenschist-amphibolite facies,where the Atalla granitic eruption provided the required temperature conditions for the metamorphic process to take *** such conditions,the transportation of ore metals as bisulfide complexes is *** deposition of ore minerals was triggered by fluidwallrock interaction through fracture pathways in conjunction with a temperature-pressure drop that is likely to have been related to uplift into the crustal levels.

关键词： Gold-silver arsenopyrite geothermometry fluid inclusions orogenic deposits Atalla Shear Zone(ASZ)

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Characterization and beneficiation of the egyptian black shale for possible extraction of organic matter

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International Journal of Mining Science and Technology 2014年第2期24卷 177-182页

作者： abd el-Rahiem F.H. Hassan M.S. Selim K.A. abdel-khalek N.A. Central Metallurgical Research and development Institute

The present paper focuses on obtaining concentrate enriched with organic matter that could be suitable for a retorting process from black shale; this is black shale from the Safaga area on the Red Sea Coast. X-ray diffraction and optical polarising microscope are used in evaluating black shale minerals. Attrition scrubbing and flotation were conducted for enrichment of organic matter in the black shale sample. Mineralogical studies revealed that black shale samples contain bituminous calcareous clay stone, quartz, apatite and pyrite. Rabah mine black shale contains 28% organic matter. The results of the different separation techniques indicate that attrition and flotation techniques successively enriched the organic matter in the black shale. The organic matter could be enriched in the black shale and obtained a concen- trate with 59% assavinz and 85% recovery.

关键词： Black shale Kerogen Organic matter Attrition scrubbing Flotation

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efficient deep-Learning-Based Autoencoder denoising Approach for Medical Image diagnosis

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Computers, Materials & Continua 2022年第3期70卷 6107-6125页

作者： Walid el-Shafai Samy abd el-Nabi el-Sayed Mel-Rabaie Anas M.Ali Naglaa F.Soliman Abeer d.Algarni Fathi e.abd el-Samie department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Alexandria Higher Institute of engineering&Technology(AIeT) AlexandriaEgypt department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia

effective medical diagnosis is dramatically expensive,especially in third-world *** of the common diseases is pneumonia,and because of the remarkable similarity between its types and the limited number of medical images for recent diseases related to pneumonia,themedical diagnosis of these diseases is a significant ***,transfer learning represents a promising solution in transferring knowledge from generic tasks to specific ***,experimentation and utilization of different models of transfer learning do not achieve satisfactory *** this study,we suggest the implementation of an automatic detectionmodel,namelyCAdTra,to efficiently diagnose pneumonia-related *** model is based on classification,denoising autoencoder,and transfer ***,pre-processing is employed to prepare the medical *** depends on an autoencoder denoising(Ad)algorithm with a modified loss function depending on a Gaussian distribution for decoder output to maximize the chances for recovering inputs and clearly demonstrate their features,in order to improve the diagnosis ***,classification is performed using a transfer learning model and a four-layer convolution neural network(FCNN)to detect *** proposed model supports binary classification of chest computed tomography(CT)images and multi-class classification of chest X-ray ***,a comparative study is introduced for the classification performance with and without the denoising *** proposed model achieves precisions of 98%and 99%for binary classification and multi-class classification,respectively,with the different ratios for training and *** demonstrate the efficiency and superiority of the proposed CAdTra model,it is compared with some recent state-of-the-art CNN *** achieved outcomes prove that the suggested model can help radiologists to detect pneumonia-related diseases and improve the diagnostic efficiency compared to the exis

关键词： Medical images CAdTra Ad CT and X-ray images autoencoder

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