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Journal of Magnesium and Alloys 2023年第7期11卷 2541-2557页

作者： Fan Shi Jingmao Zhao mohammad tabish Jingbao Wang Pu Liu Jiayu Chang College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China

The addition of 2,5-pyridinedicarboxylic acid(2,5-PDCA)to the Mg-Al LDH coating,which was prepared by one-step hydrothermal synthesis,had extremely enhanced the corrosion protection of AZ31 Mg alloy,although the 2,5-PDCA could not be intercalated into the interlayer *** corrosion current density of 0.05 mol L^(−1)2,5-PDCA LDH containing LDH coating is 3.18 nA cm^(−2),reduced by two orders of magnitude compared to the LDH coating without inhibitor,and the corrosion inhibition efficiency of the coating is 98.05%.The coating formed on the surface of AZ31 was peeled off from the substrate by using a mechanical method and SEM observation of the cross-section showed that the coating consisted of three different *** innermost layer is a thick layer that consists of Mg(OH)_(2)and the intermediate layer is LDH,which is vertical to the substrate and the outmost layer is a thin but very dense deposit layer of LDH agglomerates with complexes of 2,5-PDCA and *** kind of sediment/LDH/Mg(OH)_(2)three-layer composite structure was accountable for the increase in the corrosion resistance of AZ31 Mg alloy.

关键词： Three-layer composite coating Hydrothermal synthesis 2,5-PDCA MgAl-LDHs Peeling

不同缓蚀剂插层的Ca基LDH对Q235钢表面环氧涂层防腐性能提升作用的研究

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不同缓蚀剂插层的Ca基LDH对Q235钢表面环氧涂层防腐性能提升作用...

作者： mohammad tabish 北京化工大学

学位级别：硕士

腐蚀作为影响人们日常生活和生产的全球性问题,每年产生的损失达数百万美元。腐蚀会对国家经济产生巨大影响,造成的经济损失在国家GDP中占比达3-4%。因此,有效解决腐蚀问题迫在眉睫。碳钢广泛应用于汽车、船舶、航空航天和电子应用等各... 详细信息

腐蚀作为影响人们日常生活和生产的全球性问题,每年产生的损失达数百万美元。腐蚀会对国家经济产生巨大影响,造成的经济损失在国家GDP中占比达3-4%。因此,有效解决腐蚀问题迫在眉睫。碳钢广泛应用于汽车、船舶、航空航天和电子应用等各个领域,但因碳钢具有较高活性,当其接触腐蚀性介质时,极易被腐蚀,导致材料损失。截至目前已提出了许多防腐技术,涂层技术发展成为了重要的防腐技术之一。以有机涂层为代表的涂层技术因操作简单、性能高效等典型优势,已被广泛应用于金属防护。涂层在应用过程中,会产生不可避免的微孔缺陷等问题,腐蚀性物质能够通过这些微孔缺陷到达金属基体并造成腐蚀。为解决上述问题,填料被应用到涂层中,不仅能够提升涂层的防腐性能,还因其自愈特性能提升涂层的使用寿命。自愈涂层能够在几乎没有外部干预的情况下修复涂层缺陷并恢复其防腐性能,因此自愈涂层成为当前研究热点之一。层状双氢氧化物(LDHs)是为数不多的具有自愈合、离子交换、优异粘附性和疏水性的纳米容器之一。负载缓蚀剂的LDH用作涂层填料,能够有效提升涂层的防腐性能。因此,本文将不同缓蚀剂插层的Ca基LDH用作Q235钢表面环氧涂层的填料,旨在评估Q235钢基体上环氧基复合涂层的耐腐蚀性能和自愈合性能。首先,采用原位插层水热法制备了负载不同浓度2-巯基苯并噻唑(MBT)的Ca Al LDH涂层/粉末,并采用电化学方法确定了最佳MBT浓度。将基于最佳MBT浓度合成的CaAl MBT LDH粉末添加到环氧树脂中,研究不同用量的LDH对环氧涂层防腐性能的影响。电化学结果证明,当CaAl MBT LDH的添加量为2%时,环氧涂层的防腐性能显著增强。LDH能够吸收Cl等腐蚀性阴离子并释放MBT离子,释放的MBT离子可以与Fe发生反应,形成螯合物吸附在碳钢表面,实现对Q235钢基体的有效防护。局部电化学阻抗谱(LEIS)研究表明,复合涂层与Q235钢基体之间有很高的附着力(5.83 MPa),且表现出良好的自愈能力。其次,采用简便方法成功制备了CaFe-TTA LDH和CaFe-TTA LDH@g-CN的纳米材料。将制备的纳米材料加入环氧树脂中,以开发纳米复合涂层,并利用电化学研究了涂层的防腐性能。原始EP涂层在3.5%NaCl溶液中浸泡60天后|Z|值降低了两个数量级(从2.61×10Ωcm降低到7.69×10Ωcm),而EP/CaFe-TTA LDH和EP/CaFe-TTA LDH@g-CN涂层的|Z|值只降低了一个数量级(分别从5.49×10Ωcm降低到4.42×10Ωcm,1.18×10Ωcm降低到2.25×10Ωcm)。LEIS和盐雾试验证明涂层具备自愈性能,且被划伤的EP/TTALDH@g-CN涂层保持了原来优异的耐腐蚀性。拉脱附着力测试表明,与原始EP涂层相比,EP/TTALDH@g-CN涂层附着力强度有所提高。此外,利用DFT模拟研究了纳米填料在腐蚀过程中的反应机理。结果表明,由于EP/TTALDH@g-CN纳米填料的迷宫效应和自愈合效应,使涂层具备优异的阻隔/腐蚀抑制性能,这为开发功能化的纳米复合涂层提供了一条有效路径。

关键词：环氧树脂涂层 Ca基LDHs 填料自愈合腐蚀防护

原位法制备PDCA改性MgAl-LDHs致密双层膜研究

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原位法制备PDCA改性MgAl-LDHs致密双层膜研究

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

第十一届全国腐蚀与防护大会

作者：师凡赵景茂 mohammad tabish 北京化工大学材料科学与工程学院

层状双金属氢氧化物（LDH）由于其具有可以负载阴离子缓蚀剂的特殊层状结构而被广泛研究。部分有机、无机缓蚀剂阴离子如8-羟基喹啉[1]、海藻酸钠、2-巯基苯并噻唑[2]等可以插入层间,在腐蚀环境中释放出来从而提高材料耐蚀性。在AZ31基... 详细信息

层状双金属氢氧化物（LDH）由于其具有可以负载阴离子缓蚀剂的特殊层状结构而被广泛研究。部分有机、无机缓蚀剂阴离子如8-羟基喹啉[1]、海藻酸钠、2-巯基苯并噻唑[2]等可以插入层间,在腐蚀环境中释放出来从而提高材料耐蚀性。在AZ31基体上使用原位法制备了2,5-吡啶二羧酸（2,5-PDCA）修饰的MgAl-LDH涂层。XRD结果表明,（003）峰位没有左移,层间距未发生改变,表明2,5-PDCA并未进入LDH层间。动电位极化测试结果（图1）显示,添加2,5-PDCA后的LDH涂层相比空白组腐蚀电流密度降低了2个数量级,耐蚀性显著提高。电化学阻抗谱结果呈现为双层膜特征。SEM观察（图2）显示,在LDH层表面形成了约2μm厚的致密膜层。通过SEM、EDS、XPS等测试手段对LDH复合膜层进行研究,同时对反应时间为1、3、6和12h的中间反应过程进行了表征,探究了致密膜层的形成机理。2,5-PDCA中的羧基能够与LDH层上的羟基脱水缩合,化学吸附于LDH表面上。其独特的对称双羧基结构又能够有效的结合游离在溶液中的LDH晶体颗粒,促进表面致密膜的形成,使耐蚀性显著提高。图1不同LDH涂层在3.5%NaCl中极化曲线

关键词：镁合金层状双氢氧化物双层膜 2,5-吡啶二羧酸(2,5-PDCA)

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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

Engendered nanoparticles for treatment of brain tumors

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Oncology Research 2025年第1期33卷 15-26页

作者： SOROUSH SOLEYMANI mohammad DOROUDIAN MAHDIEH SOEZI ALI BELADI KIARASH ASGARI ASO MOBARAKSHAHI ARYANA AGHAEIPOUR RONAN MACLOUGHLIN Department of Cell and Molecular Biology School of Biological SciencesUniversity of LeicesterLeicesterLE17RHUK Department of Cell and Molecular Biology Faculty of Biological SciencesKharazmi UniversityTehran15719-14911Iran Cancer Epidemiology Research Center Aja University of Medical SciencesTehran14117-18541Iran Medical Biotechnology Research Center Aja University of Medical SciencesTehran14117-18541Iran Department of Life Sciences Faculty of Natural SciencesImperial College LondonLondonSW72AZUK School of Pharmacy and Biomolecular Sciences Royal College of Surgeons in Ireland(RCSI)DublinD02 YN77Ireland Research and Development Science and Emerging TechnologiesAerogen Ltd.Galway Business ParkGalwayH91 HE94Ireland School of Pharmacy and Pharmaceutical Sciences Trinity CollegeDublinD02 PN40Ireland

Brain metastasis and primary glioblastoma multiforme represent the most common and lethal malignant brain *** median survival time is typically less than a year after *** of the major challenges in treating these cancers is the efficiency of the transport of drugs to the central nervous *** blood-brain barrier is cooperating with advanced stages of *** blood-brain barrier poses a significant challenge to delivering systemic medications to brain *** delivery systems have emerged as promising tools for effectively crossing this ***,the development of smart nanoparticles brings new hope for cancer diagnosis and *** nanoparticles improve drug delivery efficiency,allowing for the creation of targeted and stimuli-responsive delivery *** review highlights recent advancements in nanoparticle and smart nanoparticle technologies for brain cancer treatment,exploring the range of nanoparticles under development,their applications,targeting strategies,and the latest progress in enhancing transport across the blood-brain *** also addresses the ongoing challenges and potential benefits of these innovative approaches.

关键词： Nanoparticles Smart nanoparticles Stimuli responsive nanoparticles Targeted nanoparticles Blood-brain barrier(BBB) Brain cancer

Decoding molecular mechanisms:brain aging and Alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay Ali Syed Hammad Qaiser mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir Atta-ur-Rahman School of Applied Biosciences(ASAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological Sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

关键词： Alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

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国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri mohammad Sadegh Mirdehghan mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children

Resilience-oriented intentional islanding of reconfigurable distribution power systems

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 741-752页

作者： mohammad Hossein OBOUDI mohammad mohammadI mohammad RASTEGAR Department of Power and Control Engineering School of Electrical and Computer EngineeringShiraz UniversityShirazIran

The participation of distributed energy resources in the load restoration procedure,known as intentional islanding,can significantly improve the distribution system *** system reconfiguration can effectively alter islanding procedure and thus provide an opportunity to supply more demanded energy and reduce distribution system *** addition,high-impact events such as hurricanes and earthquakes may complicate the procedure of load restoration,due to the disconnection of the distribution system from the upstream grid or concurrent component *** paper presents a two-level method for intentional islanding of a reconfigurable distribution system,considering high-impact *** thefirst level,optimal islands are selected according to the graph model of the distribution *** the second level,an optimal power flow(OPF)problem is solved to meet the operation constraints of the islands by reactive power control and demand side *** proposed problem in the first level is solved by a combination of depth first search and particle swarm optimization *** OPF problem in the second level is solved in DIgSILENT *** proposed method is implemented in the IEEE 69-bus test system,and the results show the validity and effectiveness of the proposed algorithm.

关键词： Intentional islanding Active distribution system Distributed energy resource Distribution system reconfiguration Distribution system resilience

Global Practical Stabilization of Discrete-Time Switched Affine Systems via a General Quadratic Lyapunov Function and a Decentralized Ellipsoid

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1837-1851页

作者： mohammad Hejri Department of Electrical Engineering Sahand University of TechnologySahand New TownTabriz 51335-1996Iran

This paper addresses the problem of global practical stabilization of discrete-time switched affine systems via statedependent switching *** attempts have been made to solve this problem via different types of a common quadratic Lyapunov function and an *** classical results require either the quadratic Lyapunov function or the employed ellipsoid to be of the centralized *** some cases,the ellipsoids are defined dependently as the level sets of a decentralized Lyapunov *** this paper,we extend the existing results by the simultaneous use of a general decentralized Lyapunov function and a decentralized ellipsoid parameterized *** proposed conditions provide less conservative results than existing works in the sense of the ultimate invariant set of attraction *** different approaches are proposed to extract the ultimate invariant set of attraction with a minimum size,i.e.,a purely numerical method and a numerical-analytical *** the former,both invariant and attractiveness conditions are imposed to extract the final set of matrix *** latter is established on a principle that the attractiveness of a set implies its ***,the stability conditions are derived based on only the attractiveness property as a set of matrix inequalities with a smaller *** examples are presented to prove the satisfactory operation of the proposed stabilization methods.

关键词： Decentralized quadratic Lyapunov function decentralized ellipsoid discrete-time switched affine systems practical stabilization switching power converters

Stabilizing silica nanoparticles in high saline water by using polyvinylpyrrolidone for reduction of asphaltene precipitation damage under dynamic condition

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1021-1029页

作者： mohammad Reza Aghajanzadeh mohammad Sharifi Department of Petroleum Engineering Amirkabir University of Technology

In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nanoparticles in different range of water salinity(0–100000 mg·L-1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared with the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved.

关键词： Formation damage Enhanced oil recovery Salinity Asphaltene Core flooding Nano particles