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Effect of cold deformation and heat treatment on microstructure and mechanical properties of TC21 Ti alloy

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Transactions of Nonferrous metals Society of China 2020年第5期30卷 1290-1299页

作者： Ramadan N.ELSHAER khaled m.ibrahim mechanical Engineering Department Tabbin Institute for Metallurgical Studies(TIMS)11918CairoEgypt Casting Technology Department Central Metallurgical R&D Institute(CMRDI)11918CairoEgypt

In the present research work on TC21 titanium alloy(6.5 Al-3 mo-1.9 Nb-2.2 Sn-2.2 Zr-1.5 Cr), the effects of cold deformation, solution treatment with different cooling rates and then aging on microstructure, hardness and wear property were investigated. A cold deformation at room temperature with 15% reduction in height was applied on annealed samples. The samples were solution-treated at 920 ℃ for 15 min followed by different cooling rates of water quenching(WQ), air cooling(AC) and furnace cooling(FC) to room temperature. Finally, the samples were aged at 590 ℃ for 4 h. Secondary α-platelets precipitated in residual β-phase in the case of solution-treated samples with AC condition and aged ones. The maximum hardness of HV 470 was obtained for WQ + aging condition due to the presence of high amount of residual β-matrix(69%), while the minimum hardness of HV 328 was reported for FC condition. Aging process after solution treatment can considerably enhance the wear property and this enhancement can reach up to about 122% by applying aging after WQ compared with the annealed samples.

关键词： TC21 titanium alloy deformation heat treatment cooling rate microstructure mechanical properties wear

Effect of Si-addition as a grain refiner on microstructure and properties of Ti-6Al-4V Alloy

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Transactions of Nonferrous metals Society of China 2013年第7期23卷 1863-1874页

作者： khaled m.ibrahim Abdel Hamied HUSSEIN mohamed ABDELKAWY Central metallurgical R&D Institute CMRDICairoEgypt Cairo University GizaEgypt

Two different Ti alloys were cast in a graphite mould using vacuum induction skull melting furnace. The first alloy was Ti-6Al-4V and the second was Ti-6Al-4V 0.5Si. Silicon as a grain refiner was added into Ti-6Al-4V alloy, and the effects of Si-addition on the microstructure and properties of the as-cast and swaged alloys were investigated. Hot swaging at 900 °C was performed on the cast samples and then two different thermal treatments were applied. The first treatment was done by heating the swaged samples at 1050 °C to produce fine lamella structure, while the second treatment was carried out at 1050 °C and then decreased the temperature to 800 °C for getting coarse lamella structure. An addition of 0.5% Si to Ti-6Al-4V alloy decreased the grain size of the as-cast sample from 627 to 337 μm. There was an increase in ultimate tensile strength of about 25 mPa for the as-cast Ti-6Al-4V 0.5Si alloy compared to Ti-6Al-4V due to the refinement effect caused by Si addition. A maximum ultimate tensile strength of 1380 mPa and a minimum corrosion rate （1.35×10 6 mm/a in Hank’s solution and 5.78×10 4 mm/a in NaCl solution） were reported for the heat treated fine lamella structure of Ti-6Al-4V 0.5Si alloy. The wear rate was decreased to about 50% by adding 0.5% Si at low sliding speeds and to about 73% at high sliding speeds.

关键词： Ti-6Al-4V alloy silicon casting grain refinement heat treatment wear

microstructure and mechanical properties of cast and heat treated Ti-6.55Al-3.41mo-1.77Zr alloy

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Transactions of Nonferrous metals Society of China 2013年第12期23卷 3517-3524页

作者： khaled m.ibrahim Abdel moty m.EL-HAKEEm Ramadan N.ELSHAER Certral metallurgical R&D Institute Benha University

α＋βtitanium alloy with a composition of Ti-6.55Al-3.41mo-1.77Zr （mass fraction,%） was cast into bars in a graphite mould using vacuum induction skull melting furnace （ISm）. The cast bars were hot swaged at 700 °C and then heat treated by two different regimes which resulted in fine and coarse lamella structures, respectively. The grain size of the as-cast structure was estimated to be 660 μm and the swaged samples obtained a very fine grain size in the range of 50 μm. The overall best combination of hardness, tensile properties, and wear resistance of theα＋βtitanium alloy was achieved by heat treating the samples at 1050 °C for getting fine lamellar structure. The maximum compression strength was reported for the heat treated samples at 800 °C with coarse lamella structure. The minimum wear rate was reported for the heat treated samples with fine lamellar structure and the maximum wear rate was obtained for as-cast samples due to its coarse and heterogeneity microstructure.

关键词： α+βTi-alloy casting solution treatment microstructure mechanical properties

microstructure evolution and mechanical properties of heat treated LCB titanium alloy

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Transactions of Nonferrous metals Society of China 2012年第11期22卷 2609-2615页

作者： khaled m. ibrahim mansour mHAEDE Lothar WAGNER Central metallurgical R&D Institute-CmRDI P.O. Box 87 Helwan Cairo Egypt TU-Clausthal IWW Agricolastr. 6 Clausthal-Zellerfeld Germany

The influence of ageing time on microstructure and mechanical properties of low-cost beta （LCB） titanium alloy with a chemical composition of Ti-6.6mo-4.5Fe-1.5Al was investigated. The correlation between microstructure and fatigue crack initiation and growth was also studied. Increasing ageing time tended to increase the volume fraction of the secondary α-precipitates, β-grain size and partial spheroidization of primary α-phase. The maximum tensile strength （1565 mPa） and fatigue limit （750 mPa） were obtained for the samples aged at 500 °C for 0.5 h, while the minimum ones of 1515 mPa and 625 mPa, respectively, were reported for the samples aged at 500 °C for 4 h. The samples aged at 500 °C for 4 h showed a transgranular fracture mode. However, the samples aged at 500 °C for 0.5 h revealed a mixture fracture mode of transgranular and intergranular. The formed cracks on the outer surface of the fatigue samples were found to propagate through the β-grains connecting the primary α-particles existing at the β-grain boundaries.

关键词： beta Ti alloy Ti-6.6mo-4.5Fe-1.5Al alloy fatigue crack ageing secondary α primary α β-grain tensile strength fatigue limit

An efficient nano-adsorbent via surfactants/dual surfactants assisted ultrasonic co-precipitation method for sono-removal of monoazo and diazo anionic dyes

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Chinese Journal of Chemical Engineering 2021年第12期34卷 225-236页

作者： marwa m.ibrahim Department of Chemistry Faculty of EducationAin Shams UniversityRoxy 11711CairoEgypt

To preserve the environment for civilization,we should remove the pollutants like toxic dyes by friendly and cost efficacious *** this study,the effect of surfactants or mixed surfactants on physicochemical,optical and adsorption properties of ternary mixed oxide CeO_(2)-ZrO_(2)-Al_(2) O_3(CZA) are *** ternary mixed oxide CZA was prepared by surfactants or mixed surfactants assisted ultrasonic coprecipitation *** physicochemical and optical properties are estimated by different techniques like XRD,TEm,EDX,FTIR,S_(BET) and UV-Vis/*** CZA_T and CZA_C have hybrid shapes and high surface *** adsorption properties of ternary mixed oxides adsorbents were characterized by sono-removing anionic dyes such as Congo red(CR) and Remazol red RB-133(RR).The different factors like contact time,different dye concentrations and temperatures also *** kinetics and isotherms applications showed that,the adsorption process was followed pseudo second order kinetics and the Freundlich isotherm ***,the adsorption is spontaneous and endothermic process through the thermodynamic ***,the results showed that the ternary mixed oxide nano-adsorbent(CeO_(2)-ZrO_(2)-Al_(2) O_3) is promising and functional materials for anionic dye sweep from wastewater.

关键词： CeO_(2)-ZrO_(2)-Al_(2)O_3 Surfactants Ultrasonic co-precipitation method Optical properties Wastewater Adsorption

Improving Date Fruit Classification Using Cycle GAN-Generated Dataset

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Computer modeling in Engineering & Sciences 2022年第4期131卷 331-348页

作者： Dina m.ibrahim Nada m.Elshennawy Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia Computers and Control Engineering Department Faculty of EngineeringTanta UniversityTanta37133Egypt

Dates are an important part of human *** are high in essential nutrients and provide a number of health *** fruits are also known to protect against a number of diseases,including cancer and heart *** fruits have several sizes,colors,tastes,and *** are a lot of challenges facing the date *** of the most significant challenges is the classification and sorting of *** there is no public dataset for date fruits,which is a major limitation in order to improve the performance of convolutional neural networks(CNN)models and avoid the overfitting *** this paper,an augmented date fruits dataset was developed using Deep Convolutional Generative Adversarial Networks(DCGAN)and CycleGAN approach to augment our collected date fruit *** augmentation is required to address the issue of a restricted number of images in our datasets,as well as to establish a balanced *** are three types of dates in our proposed dataset:Sukkari,Ajwa,and *** dataset augmentation,we train our created dataset using ResNet152V2 and CNN models to assess the classification process for our three categories in the *** train these two models,we start with the original ***,the models were trained using the DCGAN-generated dataset,followed by the CycleGAN-generated *** resulting results demonstrated that when using the ResNet152V2model,the CycleGAN-generated dataset had the highest classification performance with 96.8%accuracy,followed by the CNN model with 94.3%accuracy.

关键词： Dates fruits data augmentation DCGAN CycleGAN,deep learning convolution neural networks

multitarget therapeutic strategies for Alzheimer's disease

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Neural Regeneration Research 2019年第3期14卷 437-440页

作者： mostafa m.ibrahim moustafa T.Gabr Department of Pharmacognosy Faculty of Pharmacy Mansoura University Department of Basic Pharmaceutical and Toxicological Sciences College of Pharmacy University of Louisiana at Monroe Department of medicinal Chemistry Faculty of Pharmacy Mansoura University Department of Chemistry University of Iowa

Neurodegenerative diseases such as Alzheimer's, Huntington's and Parkinson's diseases have multifaceted nature because of the different factors contributing to their progression. The complex nature of neurodegenerative diseases has developed a pressing need to design multitarget-directed ligands to address the complementary pathways involved in these diseases. The major enzyme targets for development of therapeutics for Alzheimer's disease are cholinesterase and β-secretase enzymes. In this review, we discuss recent advances in profiling single target inhibitors based on these enzymes to multitarget-directed ligands as potential therapeutics for this devastating disease. In addition, therapeutics based on iron chelation strategy are discussed as well.

关键词： multitarget-directed ligands acetylcholinesterase β-secretase Alzheimer's disease hybridization neurodegenerative diseases tacrine brain permeability

An Adaptive Hate Speech Detection Approach Using Neutrosophic Neural Networks for Social media Forensics

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Computers, materials & Continua 2024年第4期79卷 243-262页

作者： Yasmine m.ibrahim Reem Essameldin Saad m.Darwish Department of Information Technology Institute of Graduate Studies and ResearchAlexandria UniversityAlexandria21526Egypt Faculty of Computers and Information Technology Egyptian E-Learning University(EELU)Giza12611Egypt Faculty of Computers and Data Science Alexandria UniversityAlexandria21554Egypt

Detecting hate speech automatically in social media forensics has emerged as a highly challenging task due tothe complex nature of language used in such platforms. Currently, several methods exist for classifying hatespeech, but they still suffer from ambiguity when differentiating between hateful and offensive content and theyalso lack accuracy. The work suggested in this paper uses a combination of the Whale Optimization Algorithm(WOA) and Particle Swarm Optimization (PSO) to adjust the weights of two multi-Layer Perceptron (mLPs)for neutrosophic sets classification. During the training process of the mLP, the WOA is employed to exploreand determine the optimal set of weights. The PSO algorithm adjusts the weights to optimize the performanceof the mLP as fine-tuning. Additionally, in this approach, two separate mLP models are employed. One mLPis dedicated to predicting degrees of truth membership, while the other mLP focuses on predicting degrees offalse membership. The difference between these memberships quantifies uncertainty, indicating the degree ofindeterminacy in predictions. The experimental results indicate the superior performance of our model comparedto previous work when evaluated on the Davidson dataset.

关键词： Hate speech detection whale optimization neutrosophic sets social media forensics

HLR-Net: A Hybrid Lip-Reading model Based on Deep Convolutional Neural Networks

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Computers, materials & Continua 2021年第8期68卷 1531-1549页

作者： Amany m.Sarhan Nada m.Elshennawy Dina m.ibrahim Department of Computers and Control Engineering Faculty of EngineeringTanta UniversityTanta37133Egypt Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia

Lip reading is typically regarded as visually interpreting the speaker’s lip movements during the *** is a task of decoding the text from the speaker’s mouth *** paper proposes a lip-reading model that helps deaf people and persons with hearing problems to understand a speaker by capturing a video of the speaker and inputting it into the proposed model to obtain the corresponding *** deep learning technologies makes it easier for users to extract a large number of different features,which can then be converted to probabilities of letters to obtain accurate *** proposed methods for lip reading are based on sequence-to-sequence architectures that are designed for natural machine translation and audio speech ***,in this paper,a deep convolutional neural network model called the hybrid lip-reading(HLR-Net)model is developed for lip reading from a *** proposed model includes three stages,namely,preprocessing,encoder,and decoder stages,which produce the output *** inception,gradient,and bidirectional GRU layers are used to build the encoder,and the attention,fully-connected,activation function layers are used to build the decoder,which performs the connectionist temporal classification(CTC).In comparison with the three recent models,namely,the LipNet model,the lip-reading model with cascaded attention(LCANet),and attention-CTC(A-ACA)model,on the GRID corpus dataset,the proposed HLR-Net model can achieve significant improvements,achieving the CER of 4.9%,WER of 9.7%,and Bleu score of 92%in the case of unseen speakers,and the CER of 1.4%,WER of 3.3%,and Bleu score of 99%in the case of overlapped speakers.

关键词： lip-reading visual speech recognition deep neural network connectionist temporal classification