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Mineralogical and Physical Characteristics of White Sandstone of Abu Rodeiyim Quarry(Sinai),and its Possible Industrial Utilization

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Acta geologica Sinica(English Edition) 2012年第2期86卷 440-446页

作者： mostafa gouda TEMRAZ Department of Exploration Egyptian Petroleum Research InstituteCairoEgypt

Mineralogical, geochemical, and textural analyses of the white sandstones （Abu Thora Fm.） of Carboniferous in the Abu Rodeiyim region show that they are fluviomarine, well-sorted, highpurity, and high-grade silica SiO2 （average 99.56%）. The results indicate that by simple treatment, the white sandstones can reach a high degree of purity, suitable for different industrial purposes （e.g. manufacture of silicon photovoltaic, crystal, and TV screens, art, and domestic and optical glass）.

关键词： white sand industrial utilization Abu Thora Sinai

Electrodeposition of nanostructured Ti/(Ru+Ti+Ce)O_2 coatings

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Rare Metals 2018年第1期37卷 13-20页

作者： Seyed mostafa Peyghambari Mardali Yousefpour Faculty of Materials and Metallurgical Engineering Semnan University

A nanostructured ternary coating of Ti/（Ru ＋ Ti ＋ Ce）O2 was prepared by the conventional electrodeposition on the titanium substrate as the cathode with different numbers of coating layers. The main objective of this work was to study nanostructured coatings of ceramic materials. For this purpose, the amount of precursor materials in the electrolyte was a variable parameter. Furthermore, the salt of TiCl4/RuCl3·xH2 O/Ce（NO3）3·6 H2 O with different amounts, hydrogen peroxide, methanol, and distilled water were used as an aqueousunaqueous bath. In addition, the coated samples were put to heat at 300, 450, 650, and 850℃ in an electric furnace for1 h. The crystalline phase of the coating was characterized by X-ray diffraction（XRD）. The chemical composition and microstructure of the coating were studied using energydispersive spectroscopy（EDS） and scanning electron microscopy analysis（SEM）. Moreover, the electrochemical measurement of Ti/（Ru ＋ Ti ＋ Ce）O2 coatings was carried out. Results show that with the increase in the number of coating layers, the quality of morphology is ***, the best quality of coatings is obtained at six layers on the titanium substrate with electrolyte including TiO2/RuO2/CeO2 with the molar ratio of 70：5：25 after heat treatment at 450 ℃ for 1 h. Besides,with the increase in Ce02 content from 5 wt% to 25 wt% and the number of coating layers, higher thickness of about（20.0±0.1） μm and minimum over potential for chlorine evolution were obtained.

关键词： Oxides Coating Heat treatment Interface Thin films

Hydrocephalus Secondary to Intraventricular Myxopapillary Ependymoma: Case Report

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World Journal of Neuroscience 2024年第3期14卷 85-91页

作者： Juan Carlos Ayala-Alvarez Onyekachi Emmanuel Anyagwa Fátima gabriela Macías-Ortiz Oluwatoyin Adalia Dairo Courtney Storm Truebody Reza Badrnejad Aishwarya Bhuta Shashwat Sandeep Phade Srushti Kishor Jamdar mostafa Yassin Vismaja Vijayan Neurology Department Hospital Civil Fray Antonio Alcalde Guadalajara Jalisco Mxico School of Medicine New Vision University Tbilisi Georgia

Ependymomas are a somewhat diverse category of glial tumors that often develop from the lining of the brain’s ventricles, or the spinal cord’s central canal. They make up 5% of all neuroepithelial tumors, 10% of paediatric brain tumors, and up to 33% of brain tumors in children under the age of three. Hydrocephalus is one of the complications, and it can be identified as progressive macrocephaly or increasing head circumference crossing percentiles, nausea, vomiting, poor appetite, irritability, and regression of developmental milestones.

关键词： Hydrocephalus Myxopapillary Ependymoma (MPE) Paediatrics Neurosurgery glioma Intracranial Hypertension

Fabrication of robust aluminum–carbon nanotube composites using ultrasonic assembly and rolling process

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 160-167页

作者： Shahab Shahsavar mostafa Ketabchi Saeed Bagherzadeh Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehranIran Department of Mechanical Engineering Technology School of Engineering TechnologyPurdue UniversityWest Lafayette47906USA

This study introduced a novel fabrication of aluminum–carbon nanotube(CNT) composites by employing bulk acoustic waves and accumulative roll bonding(ARB).In this method, CNT particles were aligned using ultrasonic standing wave in an aqueous media, and the arrayed particles were precipitated on the aluminum plate ***, the plates rolled on each other through the ARB process with four *** and scanning electron micrographs demonstrated the effective aligning of CNTs on the aluminum substrate with a negligible deviation of arrayed CNTs through the ARB *** X-ray diffraction pattern of the developed composites showed no peaks for carbon and aluminum *** addition, tensile tests showed that the longitudinal strength of the specimens processed with aligned CNTs was significantly greater than that of the specimens with common randomly dispersed *** proposed technique is beneficial for the fabrication of Al–CNT composites with directional mechanical strength.

关键词： aluminum–carbon nanotube composite ultrasonic manipulation strength microstructure

Experimental and numerical analysis of beam to column joints in steel structures

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Frontiers of Structural and Civil Engineering 2018年第4期12卷 642-661页

作者： gholamreza ABDOLLAHZADEH Seyed mostafa SHABANIAN Faculty of Civil Engineering Babol Noshirvani University of TechnologyBabolIran

The behaviors such as extreme non-elastic response, constant changes in roughness and resistance, as well as formability under extreme loads such as earthquakes are the primary challenges in the modeling of beam-to-column connections. In this research, two modeling methods including mechanical and neural network methods have been presented in order to model the complex hysteresis behavior of beam-to-column connections with flange plate. First, the component-based mechanical model will be introduced in which every source of transformation has been shown only with geometrical and material properties. This is followed by the investigation of a neural network method for direct extraction of information out of experimental data. For the validation of behavioral curves as well as training of the neural network, the experiments were carried out on samples with real dimensions of beam-to-column connections with flange plate in the laboratory. At the end, the combinational modeling framework is presented. The comparisons reveal that the combinational modeling is able to display the complex narrowed hysteresis behavior of the beam-to-column connections with flange plate. This model has also been successfully employed for the prediction of the behavior of a newly designed connection.

关键词： beam to column connections experiments component method neural network model combinational modeling

Parametric study of droplet size in an axisymmetric flow-focusing capillary device

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1016-1022页

作者： mostafa Rahimi Sajad Yazdanparast Pouya Rezai Department of Mechanical Engineering University of Mohaghegh ArdabiliArdabilIran Department of Mechanical Engineering York UniversityTorontoONCanada

A conventional technique for microfluidic droplet generation is Co-axial Flow Focusing(CFF)in which a contraction zone is placed downstream of the dispersed phase *** this contraction zone,the dispersed-phase(dphase)fluid is pinched off by continuous-phase(c-phase)fluid to generate *** the influence of multiple parameters such as the fluids velocities and viscosities,the interfacial tension,and nozzle and orifice diameters on the droplet size is of great importance for the design and application of CFF ***,development of more complete numerical models is *** this paper,we show our model is compatible with experimental data and then numerically investigate the effects of aforementioned parameters on the droplet generation in a CFF microfluidic *** results showed that the c-phase flow rate,viscosity and the interfacial tension had great impacts on the droplet *** effect of the nozzle diameter on the generated droplet size was small compared to that of the orifice in a CFF *** the simulation results,a correlation was also developed and suggested which predicts the droplet size with less than 15%error in a wide range of the introduced dimensionless parameters.

关键词： Co-axial Flow Focusing Microfluidics Droplet generation Numerical investigation

Effects of Avian Wings Color Patterns on Their Flight Performance:Experimental and Computational Studies

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Journal of Bionic Engineering 2023年第2期20卷 683-710页

作者： Ahmed Aboelezz Brenden Herkenhoff mostafa Hassanalian Department of Mechanical Engineering New Mexico Institute of Mining and TechnologySocorroNM87801USA

There are many theories behind the colors of a bird’s *** of these theories point to the color’s purpose to attract mates and hide from *** recent investigations concluded that the dark colors of birds help in reducing the drag force during flight.A new theory is presented in the current research,which states that a bird's dark color not only reduces the drag,but the color pattern also improves the overall flight performance,and each color pattern has a different type of flight performance *** difference in improvement is a result of variation in hot and cold surfaces on the bird skin as a result of the variation between light and dark feather *** prove this new theory,thermal images were captured of real bird wings under the effect of infrared ***,a novel wind tunnel wing with the ability to adjust the temperature in desired locations and patterns on the wing’s surface was manufactured and tested to evaluate the effect of aerodynamics forces as a function in the surface temperature and the hot–cold *** collected data from this wing showed potential flight efficiency improvements of 20%,comparing the lift-to-drag ratio for specific heating cases,which could increase the flight *** considering lift and drag,there were specific heating cases with corresponding angles of attack in which these parameters improved by up to 20%and 7%,*** heating cases could increase the lift at a low angle of attack,which is helpful in cruise flight performance,while some cases could increase the maximum lift coefficient by 6%.This is very helpful in lowering stall and the minimum flight ***,some cases could increase the lift-to-drag ratio,which led to an increase in the flight *** better understand the effect of the various patterns,computational fluid dynamics(CFD)simulations were conducted on the *** new theory was proved based on the CFD results and verified through the success

关键词： Aerodynamic loads CFD Drag Heated boundary layer Surface temperature

Design of on-board calibration methods for a digital sun sensor based on Levenberg–Marquardt algorithm and Kalman filters

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Chinese Journal of Aeronautics 2020年第1期33卷 339-351页

作者： Ali RAHDAN Hossein BOLANDI mostafa ABEDI Department of Electrical Engineering Iran University of Science&TechnologyTehran ***Iran Department of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran

Digital sun sensor is one of the most important sensors used in the Attitude Determination System(ADS)of the *** to the harsh environmental conditions that exist in the space,various distortions may occur in the sun sensor optical system that lead to the reduced accuracy of this ***,it is necessary to recalibrate the optical parameters of the aforementioned *** this purpose,first a novel attitude independent error model is proposed for the SS-411 sun sensor that includes the central point of the CCD array,installation error,filter thickness and sensor ***,the mutual interfaces between the sensor parameters are considered in the developed *** order to extract the sensor parameters,a nonlinear optimization technique called the Levenberg–Marquardt is applied to the developed model as a batch *** addition,the Extended Kalman Filter(EKF)and the Unscented Kalman Filter(UKF)have been utilized as sequential *** will be shown that by considering a worst case of variation amount for sensor parameters,an accuracy improvement of about 17°is achieved by the developed calibration *** between the developed algorithms represents that UKF has higher accuracy,shorter time convergence but higher computational load.

关键词： Digital sun sensor Extended Kalman filter Levenberg–Marquardt On-board calibration Unscented Kalman filter

In vitro propagation of conifers using mature shoots

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Journal of Forestry Research 2018年第3期29卷 565-574页

作者： mostafa K.Sarmast Department of Horticultural Science Faculty of Plant Production Gorgan University of Agricultural Sciences and Natural Resources (GUASNR)

Micropropagation mostly leads to the production of innumerable true-to-type plants. However, establishing pathogen-free explants through in vitro culture requires a precise management of time for the exposure of explants to antimicrobial chemicals. The application of antimicrobial chemicals must also be managed to impose the least injury on explants. This review discusses the contributions of micropropagation procedures, explant types, subculture duration, media ingredients and plant growth regulators to the in vitro response of conifer explants. Even though regeneration from mature conifer explants such as mature shoots are laborious, the chances of variation, induced in vitro, are unlikely.

关键词： Conifers Decontamination Micropropagation Tissue culture