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Rare Metals 2021年第9期40卷 2494-2500页

作者： Saira Bibi Jing-Min Wang Tariq Mehmood waheed qamar khan Cheng-Bao Jiang Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China Institute of Advanced Materials Bahauddin Zakariya UniversityMultan 60800Pakistan School of Space and Environment Beihang UniversityBeijing 100191China

Hot corrosion behavior of Sm_(2)(Co, Fe, Cu,Zr)17-type high-temperature magnetic alloy without and with a protective coating of Ni and Ni/Cr bilayer at 500 ℃ in a corrosive mixture of 75 wt% Na_(2)SO_(4)–NaCl for 100 h was reported in this paper. The obtained results of timedependent weight change established the parabolic growth of oxidized surface of bare magnets(8.87 mg·cm^(-2)),which caused a rapid loss of magnetic properties measured both at room and high temperatures(500 ℃). X-ray diffraction(XRD) analysis revealed the growth of oxides for bare magnet and Cr–oxides(Cr_(2) O_(3)), top layer of Ni/Cr bilayer coating, but in the case of single coating, Ni–sulfides formation indicated penetration of sulfur, which is further verified by electron probe microanalysis with energy dispersive spectroscopy(EPMA/EDS) *** showed that bilayer-coated samples(Ni/Cr) performed better than Ni-coated and bare samples.

关键词： Hot corrosion SmCo-based alloys Oxidation Coatings

Green corrosion inhibitors intercalated Mg:Al layered double hydroxide coatings to protect Mg alloy

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Rare Metals 2021年第8期40卷 2254-2265页

作者： Muhammad Junaid Anjum Jing-Mao Zhao Vahdat Zahedi Asl Muhammad Uzair Malik Ghulam Yasin waheed qamar khan College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing100029China Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing100029China Institute of Advanced Materials Bahauddin Zakariya UniversityMultan60800Pakistan

Mg alloy was protected with Mg:Al layered double hydroxide(LDH)coating intercalated with three green corrosion inhibitors(sodium benzoate,3-aminopropyltriethoxysilane and 8-hydroxyquinoline).The in-situ hydrothermal approach was adopted to intercalate corrosion inhibitors into Mg:Al LDH *** intercalated Mg:Al LDH coating was successfully acquired,and the crystalline structure of Mg:Al LDH coating was verified with X-ray diffraction(XRD).The organic functional groups of corrosion inhibitors were identified with the help of Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).The compact and uniform morphology was confirmed by scanning electron microscopy(SEM).The electrochemical measurement revealed better corrosion resistance of corrosion inhibitorintercalated Mg:Al LDH coatings as compared to that of pristine Mg *** corrosion protection mechanism of corrosion inhibitors was described and unearthed the corrosion inhibitor with the best performance.

关键词： Magnesium Layered double hydroxide coating Organic inhibitors Intercalation Corrosion resistance

Synthesis of yttrium and cerium doped ZnO nanoparticles as highly inexpensive and stable photocatalysts for hydrogen evolution

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Journal of Rare Earths 2021年第4期39卷 440-445页

作者： Irshad Ahmad Muhammad Shoaib Akhtar Mian Faisal Manzoor Muhammad Wajid Muhammad Noman Ejaz Ahmed Mukhtar Ahmad waheed qamar khan Anwar M.Rana Department of Physics.Bahauddin Zakariya University Multan60800Pakistan School of Computer and Communication Lanzhou University of Technology.Lanzhou730050China Department of Physics University of Agriculture Faisalabad38040Pakistan Institute of Advanced Materials Bahauddin Zakariya UniversityMultan6800Pakistan

Yttrium and cerium co-doped ZnO nanoparticles were synthesized by combustion route and characterized using X-ray diffraction(XRD),scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET),energy dispersive spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS),UV-visible diffuse reflectance spectroscopy(UV-vis DRS),photoluminescence(PL)and electrochemical impedance spectroscopy(EIS)*** introduction of yttrium ions has efficiently increased the relative percentage of Ce^(3+)ions in *** and cerium co-doped ZnO shows efficient photo activity for hydrogen evolution(10.61 mmol/((g·h))higher than previously reported optimal value for rare earth codoped ZnO *** remarkably increased hydrogen evolution can be ascribed to the synergy between electronic anchoring effect of Y^(3+)/Y^(2+)and Ce^(4+)/Ce^(3+)redox *** report presents new idea for the synthesis of efficient photocatalyst using economical route and ion anchoring *** hydrogen evolution was also tested using Na_(2)S and Na_(2)SO_(3)as electron donors under visible light *** synthesized photocatalysts also exhibit high stability.

关键词： ZnO H_(2)evolution Na_(2)SO_(3) PL Stability Rare earths

Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 123-153页

作者： Muhammad Qasim khan Fazal Malik Fahad Alturise Noor Rahman Department of Computer Science Iqra National UniversityPeshawar25000Pakistan Department of Cybersecurity College of ComputerQassim UniversityBuraydah52555Saudi Arabia Department of Computer Science and Engineering Al-Fayha CollegeAl Jubayl31961Saudi Arabia

Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband ***,they consume important and scarce network resources such as bandwidth and processing *** have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial *** paper draws its motivation from such real network disaster incidents attributed to signaling *** this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and *** provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding *** important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a *** paper presents an update and an extension of our earlier conference *** our knowledge,no similar survey study exists on the subject.

关键词： Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication

Testing Procedure for Laboratory Scale Semi Cryogenic Combustion Chamber of LPRE with Problems Faced and Lessons Learned

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Journal of Thermal Science 2022年第6期31卷 2171-2177页

作者： khan Taj Wali qamar Ihtzaz Department of Aeronautics and Astronautics Institute of Space TechnologyIslamabad 44000Pakistan

Design, development, and testing of LPRE(Liquid Propellant Rocket Engine) are difficult and expensive tasks. Prior to full-scale design, it is indispensable to optimize important parameters at sub-scale. Propellants flow rates are low for a sub-scale or laboratory scale combustion chambers. It is hard to satisfy chamber cooling and chill feed lines quickly with low flow rates of propellants. This paper proposes a detailed procedure for testing of a laboratory scale semi-cryogenic combustion chamber. Many tests were conducted with a small scale adjustable length combustion chamber. The injection head of the chamber was interchangeable. Liquid-liquid pressure swirl injector and like impinging injectors were used with two different injection heads. Liquid oxygen and kerosene were used as oxidizer and fuel, respectively. Oxidizer to fuel mixing ratio was 0.29-0.45 and the total propellant mass flow rate was 0.06-0.1 kg/s. Problems were faced during testing, including, explosion in the combustion chamber, fuel injector blockage, unstable combustion, incomplete chilling and blockage of cooling water channel, etc. A detailed procedure is designed on the basis of the lessons learned which was experimentally proved.

关键词： LPRE cryogenic testing procedure combustion chamber

A Synergistic Multi-Attribute Decision-Making Method for Educational Institutions Evaluation Using Similarity Measures of Possibility Pythagorean Fuzzy Hypersoft Sets

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 501-530页

作者： Khuram Ali khan Saba Mubeen Ishfaq Atiqe Ur Rahman Salwa El-Morsy Department of Mathematics University of SargodhaSargodha40100Pakistan Department of Mathematics University of Management and TechnologyLahore54000Pakistan Department of Mathematics College of ScienceQassim UniversityBuraydah51452Saudi Arabia

Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be *** concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such *** study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and *** results related to these operations are also modified for ***,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and ***,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested *** algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical ***,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison.

关键词： Hypersoft set Pythagorean fuzzy hypersoft set computational complexity multi-attribute decision-making optimization similarity measures uncertainty

Review of Techniques for Integrating Security in Software Development Lifecycle

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Computers, Materials & Continua 2025年第1期82卷 139-172页

作者： Hassan Saeed Imran Shafi Jamil Ahmad Adnan Ahmed khan Tahir Khurshaid Imran Ashraf College of Electrical and Mechanical Engineering National University of Sciences and Technology(NUST)Rawalpindi46604Pakistan Department of Computer Science Abasyn University Islamabad CampusIslamabad45510Pakistan Military College of Signals National University of Sciences and Technology(NUST)Rawalpindi46600Pakistan Department of Electrical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

Software-related security aspects are a growing and legitimate concern,especially with 5G data available just at our *** conduct research in this field,periodic comparative analysis is needed with the new techniques coming up *** purpose of this study is to review the recent developments in the field of security integration in the software development lifecycle(SDLC)by analyzing the articles published in the last two decades and to propose a way *** review follows Kitchenham’s review *** review has been divided into three main stages including planning,execution,and *** the selected 100 articles,it becomes evident that need of a collaborative approach is necessary for addressing critical software security risks(CSSRs)through effective risk management/estimation *** risks using a numeric scale enables a comprehensive understanding of their severity,facilitating focused resource allocation and mitigation *** a comprehensive understanding of potential vulnerabilities and proactive mitigation efforts facilitated by protection poker,organizations can prioritize resources effectively to ensure the successful outcome of projects and initiatives in today’s dynamic threat *** review reveals that threat analysis and security testing are needed to develop automated tools for the *** estimation of effort required to prioritize potential security risks is a big challenge in software *** accuracy of effort estimation can be further improved by exploring new techniques,particularly those involving deep *** is also imperative to validate these effort estimation methods to ensure all potential security threats are *** challenge is selecting the right model for each specific security *** achieve a comprehensive evaluation,researchers should use well-known benchmark checklists.

关键词： Software development lifecycle systematic literature review critical software security risks national institute of standards and technology DevSecOps open web application security project McGraw’s touch points

Exploring Nanoscale Perovskite Materials for Next‑Generation Photodetectors:A Comprehensive Review and Future Directions

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Nano-Micro Letters 2025年第2期17卷 46-108页

作者： Xin Li Sikandar Aftab Maria Mukhtar Fahmid Kabir Muhammad Farooq khan Hosameldin Helmy Hegazy Erdi Akman State Key Laboratory of Pulsed Power Laser Technology National University of Defense TechnologyHefei 230037AnhuiPeople’s Republic of China Anhui Laboratory of Advanced Laser Technology Hefei 230037AnhuiPeople’s Republic of China Nanhu Laser Laboratory Changsha 410015HunanPeople’s Republic of China Department of Semiconductor Systems Engineering and Clean Energy Sejong UniversitySeoul 05006Republic of Korea Department of Artificial Intelligence and Robotics Sejong UniversitySeoul 05006Republic of Korea School of Engineering Science Simon Fraser UniversityBurnabyBC V5A 1S6Canada Department of Electrical Engineering Sejong UniversitySeoul 05006South Korea Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Central Labs King Khalid UniversityAlQura’aP.O.Box 96061413 AbhaSaudi Arabia Scientific and Technological Research and Application Center Karamanoglu Mehmetbey University70100 KaramanTurkey

The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection *** materials are promising candidates for next-generation photodetectors(PDs)due to their unique optoelectronic properties and flexible synthesis *** review explores the approaches used in the development and use of optoelectronic devices made of different nanoscale perovskite architectures,including quantum dots,nanosheets,nanorods,nanowires,and *** a thorough analysis of recent literature,the review also addresses common issues like the mechanisms underlying the degradation of perovskite PDs and offers perspectives on potential solutions to improve stability and scalability that impede widespread *** addition,it highlights that photodetection encompasses the detection of light fields in dimensions other than light intensity and suggests potential avenues for future research to overcome these obstacles and fully realize the potential of nanoscale perovskite materials in state-of-the-art photodetection *** review provides a comprehensive overview of nanoscale perovskite PDs and guides future research efforts towards improved performance and wider applicability,making it a valuable resource for researchers.

关键词： Nanoscale perovskites Photodetectors Nanosheets Nanorods Nanowires Quantum dots Nanocrystals

Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： Khalil Ullah Song Jian Muhammad Naeem Ul Hassan Suliman khan Mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

Propagation of Ion Solitary Pulses in Dense Astrophysical Electron-Positron-Ion Magnetoplasmas

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Plasma Science and Technology 2015年第12期17卷 1000-1005页

作者： ATA-UR-RAHMAN S.A.khan A.qamar Department of Physics Theoretical Plasma Physics GroupIslamia College Peshawar(A Public Sector University) National Centre for Physics QAU Campus Department of Physics University of Peshawar

In this paper,we theoretically investigate the existence and propagation of low amplitude nonlinear ion waves in a dense plasma under the influence of a strong magnetic *** plasma consists of ultra-relativistic and degenerate electrons and positrons and non-degenerate cold ***,the appearance of two distinct linear modes and their evolution is studied by deriving a dispersion equation with the aid of Fourier ***,the dynamics of low amplitude ion solitary structures is investigated via a Korteweg-de Vries equation derived by employing a reductive perturbation *** effects of various plasma parameters like positron concentration,strength of magnetic field,obliqueness of field,etc.,are discussed in *** the end,analytical results are supplemented through numerical analysis by using typical representative parameters consistent with degenerate and ultra-relativistic magnetoplasmas of astrophysical regimes.

关键词： degenerate relativistic perturbation solitary representative Electron appearance dense collective normalized