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Oxidation Mechanisms in MgO-C Refractories

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China's Refractories 2004年第2期13卷 13-20页

作者： B.Hashemi z.ali Nemati S.K.Sadrnezhaad Department of Materials Science and Engineering Department of Materials Science and Engineering Department of Materials Science and Engineering Sharif University of Technology TehranIran11365-9466Sharif University of Technology TehranIran11365-9466Sharif University of Technology TehranIran11365-9466

An investigation on the oxidation mechanism of the graphite in the MgO-C refractory materials is helpful to improving both the quality of these materials and to preventing and/or lowering of the adverse effects of the high-temperature oxidation. In this research, the oxidation behavior of the MgO-C refractories containing 5～20 wt% graphite was studied via weight-loss method. Atmospheric air was used for oxidation at temperatures ranging from 900℃ to 1300°C and the experimental data were compared with those obtained from the dimensionless kinetic equations of the shrinking core model, in order to determine the oxidation mechanisms of the refractories. The best fit was achieved with the porous layer diffusion control regime. Oxidation mechanism tends, however, to slightly deviate from pure pore diffusion control to pore diffusion-external gas transfer regime in the samples having more graphite contents (e.g. 20%).

关键词： MgO Carbon Diffusion Refractories Oxidation

Physical and Kinematical Characteristics of Wolf–Rayet Central Stars and their Host Planetary Nebulae

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Research in Astronomy and Astrophysics 2023年第9期23卷 219-240页

作者： z.Awad A.ali Department of Astronomy Space Science and MeteorologyFaculty of ScienceCairo University12613 Giza

We address the physical and kinematical properties of Wolf–Rayet[WR]central stars(CSs)and their host planetary nebulae(PNe).The studied sample comprises all[WR]CSs that are currently *** analysis is based on recent observations of the parallax,proper motion,and color index of[WR]CSs from the Gaia space mission’s early third release(eDR3)catalog,as well as common nebular *** results revealed an evolutionary sequence,in terms of decreasing Teff,from the early hot[WO 1]to the late cold[WC 12]*** evolutionary sequence extends beyond[WR]CS temperature and luminosity to additional CS and nebular *** statistical analysis shows that the mean final stellar mass and evolutionary age of the[WR]CS sample are 0.595±0.13M⊙and 9449±2437 yr,respectively,with a mean nebular dynamical age of 7270±1380 *** addition,we recognize that the color of the majority(∼85%)of[WR]CSs tends to be red rather than their genuine blue *** analysis indicates that two-thirds of the apparent red color of most[WR]s is attributed to the interstellar extinction whereas the other one-third is due to the PN self-extinction effect.

关键词： Wolf-Rayet-(ISM )planetary nebulae general-ISM kinematics and dynamics

Driving pressure in acute respiratory distress syndrome for developing a protective lung strategy:A systematic review

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World Journal of Critical Care Medicine 2025年第2期14卷 158-169页

作者： Hassan A Alzahrani Nadia Corcione Saeed M Alghamdi Abdulghani O Alhindi Ola A Albishi Murad M Mawlawi Wheb O Nofal Samah M ali Saad A Albadrani Meshari A AlJuaid Abdullah M Alshehri Mutlaq z Alzluaq Department of Respiratory Care Medical Cities at the Minister of InteriorRiyadh 13321Saudi Arabia Interventional Pulmonology Antonio Cardarelli HospitalNaplesItaly Department of Clinical Technology Respiratory Care ProgramUmm-Al Qura UniversityMakkah al Mukarramah 21599Saudi Arabia Respiratory Therapy Unit Security Forced Hospital ProgramMakkah al Mukarramah 26955Saudi Arabia Department of Medical Affairs Security Forced Hospital ProgramMakkah al Mukarramah 25911Saudi Arabia Department of Intensive Care Unit and Medical Affairs Security Forced Hospital ProgramMakkah al Mukarramah 23455Saudi Arabia Department of Pharmacy Security Forced Hospital ProgramMakkah al Mukarramah 23455Saudi Arabia Department of Internal Medicine Security Forced Hospital ProgramMakkah al Mukarramah 21955Saudi Arabia Department of Respiratory Therapy King Faisal Medical ComplexTaif 29167Saudi Arabia Department of Respiratory Therapy King FahadGeneral HospitalTaif 29167Saudi Arabia Department of Respiratory Therapy East Jeddah HospitalFirst Jeddah ClusterJeddah 23235Saudi Arabia

BACKGROUND Acute respiratory distress syndrome(ARDS)is a critical condition characterized by acute hypoxemia,non-cardiogenic pulmonary edema,and decreased lung *** Berlin definition,updated in 2012,classifies ARDS severity based on the partial pressure of arterial oxygen/fractional inspired oxygen fraction *** various treatment strategies,ARDS remains a significant public health concern with high mortality *** To evaluate the implications of driving pressure(DP)in ARDS management and its potential as a protective lung *** We conducted a systematic review using databases including EbscoHost,MEDLINE,CINAHL,PubMed,and Google *** search was limited to articles published between January 2015 and September ***-three peer-reviewed articles were selected based on inclusion criteria focusing on adult ARDS patients undergoing mechanical ventilation and DP *** literature review was conducted and reported according to PRISMA 2020 *** DP,the difference between plateau pressure and positive end-expiratory pressure,is crucial in ARDS *** indicate that lower DP levels are significantly associated with improved survival rates in ARDS *** is a better predictor of mortality than tidal volume or positive end-expiratory pressure *** DP by optimizing lung compliance and minimizing overdistension and collapse can reduce ventilator-induced lung *** DP is a valuable parameter in ARDS management,offering a more precise measure of lung stress and strain than traditional *** DP as a threshold for safety can enhance protective ventilation strategies,po-tentially reducing mortality in ARDS *** research is needed to refine DP measurement techniques and validate its clinical application in diverse patient populations.

关键词： Acute respiratory distress syndrome Mechanical ventilation Driving pressure Respiratory care Intensive care unit Pulmonary disease

Slip effects on streamline topologies and their bifurcations for peristaltic flows of a viscous fluid

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Chinese Physics B 2014年第6期23卷 341-352页

作者： z.Asghar N.ali Department of Mathematics and Statistics International Islamic University

We discuss the effects of the surface slip on streamline patterns and their bifurcations for the peristaltic transport of a Newtonian fluid. The flow is in a two-dimensional symmetric channel or an axisymmetric tube. An exact expression for the stream function is obtained in the wave frame under the assumptions of long wavelength and low Reynolds number for both cases. For the discussion of the particle path in the wave frame, a system of nonlinear autonomous differential equations is established and the methods of dynamical systems are used to discuss the local bifurcations and their topological changes. Moreover, all types of bifurcations and their topological changes are discussed graphically. Finally, the global bifurcation diagram is used to summarize the bifurcations.

关键词： viscous fluid slip condition streamline topologies bifurcation

Notes on Curves at a Constant Distance from the Edge of Regression on a Curve in Galilean 3-Space G_(3)

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2731-2742页

作者： ali Cakmak Sezai Kızıltug Gokhan Mumcu Department of Mathematics Faculty of Arts and SciencesBitlis Eren UniversityBitlis13000Turkey Graduate School of Natural and Applied Sciences Erzincan Binali Yıldırım UniversityErzincan24002Turkey Department of Mathematics Faculty of Arts and ScienceErzincan Binali Yıldırım UniversityErzincan24002Turkey

In this paper,we define the curve rλ=r+λd at a constant distance from the edge of regression on a curve r(s)with arc length parameter s in Galilean ***,d is a non-isotropic or isotropic vector defined as a vector tightly fastened to Frenet trihedron of the curve r(s)in 3-dimensional Galilean *** build the Frenet frame{Tλ,Nλ,Bλ}of the constructed curve rλwith respect to two types of the vector d and we indicate the properties related to the curvatures of the curve rλ.Also,for the curve rλ,we give the conditions to be a circular ***,we discuss ruled surfaces of type A generated via the curve rλand the vector D which is defined as tangent of the curve rλin 3-dimensional Galilean *** constructed ruled surfaces also appear in two *** first is constructed with the curve rλ(s)=r(s)+λT(s)and the non-isotropic vector *** second is formed by the curve rλ=r(s)+λ2N+λ3B and the non-isotropic vector *** calculate the distribution parameters of the constructed ruled surfaces and we show that the ruled surfaces are ***,we provide examples and visuals to back up our research.

关键词： Edge of regression Galilean space curvature helix ruled surface

A Secure Communication Protocol for Unmanned Aerial Vehicles

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Computers, Materials & Continua 2022年第1期70卷 601-618页

作者： Navid ali Khan N.z.Jhanjhi Sarfraz Nawaz Brohi Abdulwahab ali Almazroi Abdulaleem ali Almazroi School of Computer Science and Engineering(SCE) Taylor’s University Lake-side CampusSubang Jaya47500Malaysia School of Information and Technology Monash UniversityMalaysia University of Jeddah College of Computing and Information Technology at KhulaisDepartment of Information TechnologyJeddahSaudi Arabia Department of Computer Science Rafha Community CollegeNorthern Border UniversityArar91431Saudi Arabia

Mavlink is a lightweight and most widely used open-source communication protocol used for Unmanned Aerial *** UAVs and autopilot systems support it,and it provides bi-directional communication between the UAV and Ground Control *** communications contain critical information about the UAV status and basic control commands sent from GCS to UAV and UAV to *** order to increase the transfer speed and efficiency,the Mavlink does not encrypt the *** a result,the protocol is vulnerable to various security attacks such as Eavesdropping,GPS Spoofing,and *** this study,we tackle the problem and secure the Mavlink communication *** leveraging the Mavlink packet’s vulnerabilities,this research work introduces an experiment in which,first,the Mavlink packets are compromised in terms of security requirements based on our threat *** results show that the protocol is insecure and the attacks carried out are *** overcomeMavlink security,an additional security layer is added to encrypt and secure the *** encryption technique is proposed that makes the communication between the UAV and GCS *** results show that the Mavlink packets are encrypted using our technique without affecting the performance and *** results are validated in terms of transfer speed,performance,and efficiency compared to the literature solutions such as MAVSec and benchmarked with the original Mavlink *** achieved results have significant improvement over the literature and Mavlink in terms of security.

关键词： Unmanned aerial vehicles mavlink protocol drones security UAVs communication

Quick screening and easy detection method of NDM-gene in clinical isolates:A need of the time

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Asian Pacific Journal of Tropical Medicine 2012年第10期5卷 839-840页

作者： Asad U Khan Saeedut z.ali Interdisciplinary Biotechnology Unit Aligarh Muslim University

The emerging trend of multidrug resistance is becoming a major threat to community acquired and nosocomial infections,worldwide[1].The carbapenems are used as last-source drugs because of increasing resistance against... 详细信息

关键词： screening lactam nosocomial antibiotics isolates threat becoming emerging resist DNA

Pressure and Discharge-Voltage Dependence of Self-Sustaining Pulses in Air-Glow Discharge

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Chinese Physics Letters 2012年第5期29卷 181-184页

作者： A.A.Azooz Y.A.Al-Jawaady z.T.ali Department of Physics College of ScienceMosul UniversityMosulIraq

The details of formation of micro discharges in air-glow discharge plasma are experimentally *** number of micro discharges formed per second is strongly related to both pressure and discharge *** number tends to show reflections of the Patchen curve as far as its pressure dependence is *** dischargevoltage dependence indicates that the transition from normal to abnormal glow discharge is not a sudden one,but has its roots during the normal glow stage and is initiated by the micro discharges which can be regarded as the early stage of abnormal glow.

关键词： details initiated roots

Topology-Optimized 4D Printing of a Soft Actuator

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Acta Mechanica Solida Sinica 2020年第3期33卷 418-430页

作者： ali zolfagharian Martin Denk Mahdi Bodaghi Abbas z.Kouzani Akif Kaynak School of Engineering Deakin UniversityGeelong 3216Australia Munich University of Applied Sciences 80335 MunichGermany Department of Engineering School of Science and TechnologyNottingham Trent UniversityNottingham NG 118NSUK

Soft robots and actuators are emerging devices providing more capabilities in the field of *** flexibility and compliance attributing to soft functional materials used in the fabrication of these devices make them ideal for delivering delicate tasks in fragile environments,such as food and biomedical ***,the intuitive nonlinearity of soft functional materials and their anisotropic actuation in compliant mechanisms constitute an existent challenge in improving their *** optimization(TO)along with four-dimensional(4D)printing is a powerful digital tool that can be used to obtain optimal internal architectures for the efficient performance of porous soft *** paper employs TO analysis for achieving high bending deflection of a 3D printed polyelectrolyte actuator,which shows bending deformations in response to electrical stimuli in an electrolyte *** performance of the actuator is studied in terms of maximum bending and actuation rate compared with a solid,uniformly 3D printed and topology-optimized *** experimental results proved the effectiveness of TO on achieving higher bending deformation and actuation rate against a uniformly 3D printed actuator.

关键词： Topology optimization 4D printing 3D printing Soft actuator