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Chinese Journal of Chemical Engineering 2017年第12期25卷 1820-1830页

作者： mostafa Lashkarbolooki Shahab Ayatollahi School of Chemical Engineering Babol Noshirvani University of Technology Babol Iran School of Chemical and Petroleum Engineering Sharif University of Technology Tehran Iran

In this way, after experimental measurement of interfacial tension, different models including mono-exponential decay, dynamic adsorption models and empirical equation are used to correlate this time-dependent behavior of interfacial tension(IFT). During the modeling approach, the induction, adsorption, equilibrium, and mesoequilibrium times as well as diffusivity of surface active components known as natural surfactant including asphaltene and resin from crude oil to the interface are obtained. In addition, the surface excess concentration of surface active components at the interface and Gibbs adsorption isotherm are utilized to analyze the measured dynamic IFTs. Finally, the mechanisms of crude oil/aqueous solution IFT including(a) the activity of surfaceactive components and(b) surface excess concentration of them at fluid/fluid interface are proposed and discussed in details.

关键词： Dynamic IFT Adsorption Ion Crude oil EOR

Reinforcement selection for deep and high-stress tunnels at preliminary design stages using ground demand and support capacity approach

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International Journal of Mining Science and Technology 2018年第4期28卷 571-580页

作者： Reza Masoudi mostafa Sharifzadeh Department of Mining&Metallurgical Engineering Curtin University Western Australian School of Mines(WASM)Perth 6102Australia

Underground mining is going to be deeper gradually because near surface resources are going to be depleted. Therefore, risk of seismic events in underground mines is escalating. Additionally, existence of the large ratio of horizontal to vertical stress, could be a potential reason for high-stress condition and occurrence of dynamic activities. Depending on various parameters such as the level of induced stress, rock properties, etc., ground demand changes and it is difficult to estimate. On the other hand,under seismic condition, energy dissipation and deformation capacity of supports is the most important factors, however, rock support performance factors in dynamic conditions are still under *** the knowledge of reinforcement behaviour and capacity, specifically that of the rockbolt as a primary element in seismic conditions, would help to develop a suitable, safe and economic support design. This paper contains various methods to estimate ground demand including the intact rock properties approach, failure thickness and ejection velocity estimation, and rockburst damage potential method. It also covers measurement methods of rockbolts energy dissipation capacities such as drop test,blasting simulating, back calculation and momentum transfer measurement methods. A large-scale dynamic test rig is also explained. Based on the findings, a table and a graph to show the applicable range of each type of rockbolts were presented. Suitable rockbolt types for various ground energy demand and deformation capacity range were categorised in the table and the graph. The presented support selection method facilitates the selection of a suitable reinforcement system at the preliminary stages of design and guides the designer to adjust the support reinforcement system based on observed ground and support reaction.

关键词： High-stress tunnels Support system Ground demand Reinforcement capacity Rockbolt

Inelastic displacement ratio of low-to mid-rise BRBFs designed under variable levels of seismicity

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 763-775页

作者： Hamdy Abou-Elfath mostafa Ramadan Faculty of Engineering Alexandria UniversityAlexandria 21544Egypt

Buckling-restrained braces(BRBs)have shown their capability to provide building structures with stiffness,strength,and *** the seismic drifts of buckling-restrained braced frames(BRBFs)is an important design step to control structural and non-structural *** current practice of seismic design,the estimation of seismic drifts of BRBFs is performed by using empirical calculations that are independent upon either the type of the structural system or the design level of *** these empirical calculations,the seismic drifts are estimated by amplifying the reduced elastic drifts obtained under design lateral loading with a displacement amplification factor(DAF).The value of DAF is considered equal to the product of the response modification factor R and the inelastic displacement ratioρ.The goal of the current research is to assess the value ofρfor low-to mid-rise BRBFs designed under low and high levels of *** goal has been achieved by conducting a series of elastic and inelastic time-history analyses pertaining to an ensemble of earthquake records on 3-,6-and 9-story *** results indicate that theρ-ratio increases with an increase in design seismic intensity and an increase in experienced *** range ofρfor low seismicity designs ranges from 0.63 to 0.9,while for high seismicity designs this range stretches from 0.83 to *** has been found that the consideration of a generalρ-ratio of 1.0 is a reasonable estimation for the design of the BRBFs considered in this study.

关键词： displacement amplification factor inelastic displacement ratio seismicity buckling-restrained brace seismic drift seismic design

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