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Exact Solution of Non-Newtonian Blood Flow with Nanoparticles through Porous Arteries:A Comparative Study

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Computers, Materials & Continua 2020年第6期63卷 1143-1157页

作者： Wafaa Alharbi Abdulrahman Aljohani essam El-zahar Abdelhalim Ebaid Department of Mathematics Faculty of ScienceUniversity of TabukTabuk71491Saudi Arabia Department of Mathematics College of Sciences and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of Basic Engineering Science Faculty of EngineeringMenofia UniversityShebin El-Kom32511Egypt

In this paper,the mathematical model describing the third-grade non-Newtonian blood flow suspended with nanoparticles through porous arteries is exactly *** present physical model was solved in the research literature via the optimal homotopy analysis method and the collocation method,where the obtained solution was compared with the numerical fourth-order Runge-Kutta ***,the present paper only introduces a new approach to obtain the exact solution of the concerned system and implements such exact solution as a reference to validate the published approximate *** remarks on the previously published results are observed and discussed in detail through tables and *** view of the present calculations,the obtained results in the literature by Ghasemi et al.[Ghasemi,Hatami,Sarokolaie et al.(2015)]may need ***,it is found that the obtained approximate results in the relevant literature agree with the current exact ones up to only two or three decimal places,at ***,the present approach along with the obtained results reflexes the effectiveness and efficiency of our analysis when compared with the corresponding study in the ***,the present results can be directly invested for similar future problems of the same constructions.

关键词： Nanofluid blood flow porous artery nanoparticle exact solution

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： Gürel Cam Ali Günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Effect of Wood-drying Condensate on Emission of Volatile Organic Compounds and Bonding Properties of Fibreboard

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Journal of Bionic Engineering 2020年第1期17卷 206-214页

作者： Nadir Ayrilmis Tolga Kapti Ali Gürel Martin Ohlmeyer Department of Wood Mechanics and Technology Forest FacultyIstanbul University-CerrahpasaIstanbul 34473Turkey Polisan Kimya San.A.(S). Dilovas(i)Organize Sanayi B(o)lgesi 1.K(i)s(i)m Liman Cad.No:7Dilovas(i)41455Turkey Forest Research Institute Marmara RegionGeneral Directorate of Forestry of TurkeyIstanbul 34398Turkey Thünen-Institut für Holzforschung Thünen Institute of Wood ResearchLeuschnerstr.91 cHamburg 21031Germany

Potential use of condensate generated by cooling the steam obtained during high-frequency/vacuum drying step of hardwood lumber was *** liquid condensates were obtained from oak,beech and walnut *** liquid condensate was then used as a replacement for deionized water in the synthesis of Urea-Formaldehyde(UF)resin(5 wt%of total resin)using a laboratory scale *** Density Fibreboards(MDFs)were produced using control and modified *** of Volatile Organic Compounds(VOCs)from the MDFs were determined by Micro Chamber *** bonding properties of the MDFs were determined according to European *** main VOC emissions from MDFs produced using UF resin containing the condensate were a-Pinene,b-Pinene,careen,and acetic acid,which were lower than those of the control MDF,except for the acetic acid emission of MDF with oak *** the tree species,the beech wood condensate gave the lowest VOC emissions(732μg·m^-3)from the MDFs,followed by the MDFs containing walnut wood condensate(852μg·m^-3),oak wood condensate(998μg·m^-3),and control MDF(3529μg·m^-3),***,the internal bond strength of MDFs containing the condensate was negatively impacted by the condensate(0.70 N·mm^-2 to 0.54 N·mm^-2 depending on the tree species).The results showed that the liquid wood-drying condensate which generally released to the ground could be efficiently used as an alternative to expensive VOCs scavenger used in the production of UF resin bonded *** may be one of the most efficient uses of the condensate in high value-added materials.

关键词： bionics condensate fibreboard urea-formaldehyde VOCs

A New Fractional Model for the Falling Body Problem

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Chinese Physics Letters 2017年第2期34卷 1-3页

作者： A.Ebaid B.Masaedeh E.E1-zahar Department of Mathematics Faculty of ScienceTabuk UniversityP.O.Box 741Tabuk 71491Kingdom of Saudi Arabia Department of Mathematics Faculty of Sciences and HumanitiesPrince Sattam Bin Abdulaziz UniversityA1kharj11942Kingdom of Saudi Arabia Department of Basic Engineering Science Faculty of EngineeringShebin El-Kom32511Menofia UniversityEgypt

Recently, a conformable fractional derivative has been proposed to calculate the derivative of non-integer order of time functions. It has been shown that this new fractional derivative definition obeys many advantages over the preceding definitions. For mathematical models in applied sciences and to preserve the dimensionality of the physical quantities, an auxiliary parameter （~r） which has the dimension of seconds should be implemented in the fractional derivative definition. We obtain analytic solutions for the resulting conformable fractional differential equations describing the vertical velocity and the height of the falling body. It is shown that the dimensions of velocity and height are always correct without any restrictions on the auxiliary parameter cr which contradicts with the results in the literature when applying the Caputo definition to the same problem. This may open the door for many future works either to describe the role of such an auxiliary parameter or to derive a more suitable definition for the fractional derivative.

关键词： A New Fractional Model for the Falling Body Problem

Study of parameters affecting infection risk from contaminated injectable products using multiple spot contamination model: a case study of insulin vials

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Journal of Chinese Pharmaceutical Sciences 2016年第11期25卷 832-837页

作者： Mostafa essam Eissa Hikma Pharma for Pharmaceutical Industry 2nd Industrial Zone

Infections of patients from consumption of contaminated pharmaceutical products constituted major health risk problems. Medicinal products are liable to microbial intrusion during in-use application. The current study focused on repeated contamination with constant level of microbiological burden by two bacteria viz. Staphylococcus aureus and Pseudomonas aeruginosa were used as dose-response models for infection through two different routes of administration. Nine different forms of insulin vials were subjected to this type of simulation study at constant assumed level of contaminations, preservative efficacy test(PET) and dose potency. Multi-spot contamination imitation study showed that initial fast rise in contamination, followed shortly by longer but steeper slope which finally turned into higher rate of contamination during the few last doses of the unit dosage forms, where the volume of the product became increasingly and progressively very small. When the probability of infection curves was constructed, both S. aureus and P. aeruginosa showed same pattern, with notably higher risk from septicemia route of the latter rather than subcutaneous route of the former. The present simulation study showed that continuous use of the same contaminated syringe progressively increased the risk of infection, especially at final few doses(between 3th and 10 th last doses depending on the dosage form sizes in the vials and the administration volumes) of the product. Small volume parenterals(SVP) are especially products at higher risk than the larger volume ones.

关键词： Insulin vials Staphylococcus aureus Pseudomonas aeruginosa Multi-spot contamination PET Simulation study

Evaluation of the microstructure,thermal and mechanical properties of Cu/SiC nanocomposites fabricated by mechanical alloying

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 475-486页

作者： essam B.Moustafa Mohammed A.Taha Mechanical Engineering Departments Faculty of EngineeringKing Abdulaziz UniversityJeddah 21589Saudi Arabia Solid State Physics Department National Research CentreEl Buhouth St.Dokki12622 GizaEgypt

Nano-sized silicon carbide(SiC:0wt%,1wt%,2wt%,4wt%,and 8wt%)reinforced copper(Cu)matrix nanocomposites were manufactured,pressed,and sintered at 775 and 875℃in an argon atmosphere.X-ray diffraction(XRD)and scanning electron microscopy were performed to characterize the microstructural *** density,thermal expansion,mechanical,and electrical properties were *** analyses showed that with increasing SiC content,the microstrain and dislocation density increased,while the crystal size *** coefficient of thermal expansion(CTE)of the nanocomposites was less than that of the Cu *** improvement in the CTE with increasing sintering temperature may be because of densification of the ***,the mechanical properties of these nanocomposites showed noticeable enhancements with the addition of SiC and sintering temperatures,where the microhardness and apparent strengthening efficiency of nanocomposites containing 8wt%SiC and sintered at 875℃were 958.7 MPa and 1.07 vol%^(−1),*** electrical conductivity of the sample slightly decreased with additional SiC and increased with sintering *** prepared Cu/SiC nanocomposites possessed good electrical conductivity,high thermal stability,and excellent mechanical properties.

关键词： copper matrix nanocomposites silicon carbide coefficient of thermal expansion elastic moduli electrical conductivity mechanical alloying

A VHDL application for kinematic equation solutions of multi-degree-of-freedom systems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第12期15卷 1164-1173页

作者： Hüseyin Oktay ERKOL Hüseyin DEMírel Department of Mechatronics Engineering Faculty of Technology Karabük University Department of Electrical and Electronics Engineering Faculty of Engineering Karabük University

As kinematic calculations are complicated, it takes a long time and is difficult to get the desired accurate result with a single processor in real-time motion control of multi-degree-of-freedom(MDOF) systems. Another calculation unit is needed, especially with the increase in the degree of freedom. The main central processing unit(CPU) has additional loads because of numerous motion elements which move independently from each other and their closed-loop controls. The system designed is also complicated because there are many parts and cabling. This paper presents the design and implementation of a hardware that will provide solutions to these problems. It is realized using the Very High Speed Integrated Circuit Hardware Description Language(VHDL) and field-programmable gate array(FPGA). This hardware is designed for a six-legged robot and has been working with servo motors controlled via the serial port. The hardware on FPGA calculates the required joint angles for the feet positions received from the serial port and sends the calculated angels to the servo motors via the serial port. This hardware has a co-processor for the calculation of kinematic equations and can be used together with the equipment that would reduce the electromechanical mess. It is intended to be used as a tool which will accelerate the transition from design to application for robots.

关键词： Multi-degree-of-freedom systems Kinematics Co-processor Serial communication Six-legged robot

Using random-parameter and fixed-parameter ordered models to explore temporal stability in factors affecting drivers' injury severity in single-vehicle collisions

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第2期6卷 132-146页

作者： essam Dabbour Murtaza Haider Eman Diaa College of Engineering Abu Dhabi University Ted Rogers School of Management Ryerson University

Understanding the temporal stability in the factors influencing drivers' injury severity in single-vehicle collisions would help evaluating the effectiveness of implementing different safety treatments so that researchers could understand whether any safety improvements,observed after applying a certain safety treatment, are attributed to the specific treatment or simply attributed to the temporal instability of the factors being addressed. This study investigates the temporal stability of the factors affecting drivers' injury severity in singlevehicle collisions involving light-duty vehicles. The study is based on utilizing ordinal regression modeling to analyze the severity of drivers' injuries in all police-reported lightduty single-vehicle collisions that occurred in North Carolina from January 1, 2007, to December 31, 2013. A separate regression model was estimated for each year so that statistical significance of each risk factor may be compared over the years. The study also estimated random-parameter(mixed) ordered logit models to explore the heterogeneity in data. The most significant factor that was found to increase the severity of drivers' injuries in light-duty single-vehicle collisions is driving under the influence of alcohol or illicit drugs. Other significant factors, in decreasing order in terms of their significance, include driving on a highway curve, exceeding speed limit, lighting conditions, the age of the driver, and the age of the vehicle. In contrast, there were six factors that were found to be significant in only some years and not in all years. These six temporally unstable factors include the use of seatbelt, driver's gender, rural highways, undivided highways, the type of the light-duty vehicle, and weather and road surface conditions. These same factors were found by other previous research studies to be significant and stable predictors of drivers' injury severity in single-vehicle collisions.

关键词： Drivers' injury severity Single-vehicle collisions Ordinal regression models Mixed logit models Temporal stability

Immobilization of Co(Ⅱ) Ions in Cement Pastes and Their Effects on the Hydration Characteristics

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Journal of Materials Science & Technology 2011年第1期27卷 74-80页

作者： Eisa Hekal essam Kishar Wafaa Hegazi Maha Mohamed Chemistry Department Faculty of ScienceAin Shams University Chemistry Department Women s College for ArtsScience and EducationAin Shams University

The immobilization of Co（Ⅱ） in various cement matrices was investigated by using the solidification/stabilization（S/S） *** different cement pastes used in this study were ordinary Portland cement in absence and presence of water reducing-and water repelling-admixtures as well as blended cement with *** ratios of Co（Ⅱ） were used（0.5% and 1.0% by weight of the solid binder）.The hydration characteristics of the used cement pastes were tested via the determination of the combined water content,phase composition and compressive strength at different time intervals up to 180 *** degree of immobilization of the added heavy metal ions was evaluated by determining the leached ion concentration after time intervals extended up to 180 *** leachability experiments were carried out by using two modes：the static and the semi-dynamic leaching *** was noticed that the concentration of the leached Co2＋ ions in the static mode of leachability was lower than the solubility of its hydroxide in all the investigated cement pastes.

关键词： Hydration characteristic of cement Admixtures Immobilization Heavy metals