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Aluminium and cerium co-doped ZnO nanoparticles:Facile and inexpensive synthesis and visible light photocatalytic performances

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Journal of Rare Earths 2021年第2期39卷 151-159页

作者： Irshad Ahmad Muhammad shoaib Akhtar Ejaz ahmed Mukhtar Ahmad Department of Physics Bahauddin Zakariya UniversityMultan60800Pakistan School of Computer and Communication Lanzhou University of TechnologyLanzhou 730000China

Facile combustion route synthesized Al and Ce co-doped ZnO nanoparticles photocatalysts were characterized using XRD,SEM,BET,EDS,UV-visible DRS,PL,photocurrent and EIS *** and SEM analyses identify that crystallite and particle size is reduced from 13.26 to 11.88 nm with introduction of Al and Ce into ZnO which assists inhibiting the recombination of photo generated charge *** DRS spectra indicate that optical assimilation of ZnO is significantly increased to visible region(-406 nm)and band gap reduces from 3.18 to 3.06 eV with introduction of Al and Ce *** impedance spectroscopy analysis under visible light illumination confirms the enhancement in visible light activity of Al and Ce co-doped ZnO nanoparticles as *** enhanced activity of Al and Ce co-doped ZnO photocatalyst can be ascribed to enhanced light assimilation,high surface area and efficient charge transfer *** results reveal that by incorporating precise amount of Al(~2%)and Ce(~2%)into ZnO,a highly efficient catalyst can be synthesized that have degraded almost 95%methyl orange(MO)dye in just 45 ***,the influence of various operational parameters such as solution pH,catalyst dose,dye concentration,airflow rate and light intensity on photodecomposition of MO was *** rmore,a possible mechanism for Al and Ce modified ZnO was proposed and designed photocatalysts demonstrates good stability in aqueous medium.

关键词： Nanoparticles ZnO Combustion MO decomposition PL Rare earths

Risk Assessment of Failure Modes Related to Marine Boiler Using Fuzzy Expert System

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Risk Assessment of Failure Modes Related to Marine Boiler Us...

作者： shoaib ahmed 上海交通大学

学位级别：硕士

船用锅炉作为一个复杂的高温易燃易爆机械系统蕴涵着巨大的事故风险,轻者会丧失锅炉的部分功能,重者会引发船舶的海难事故,造成难以估量的生命和财产损失。商船的锅炉故障往往会造成灾难性的后果,特别是对于船舶机械制造商、海事工程师... 详细信息

船用锅炉作为一个复杂的高温易燃易爆机械系统蕴涵着巨大的事故风险,轻者会丧失锅炉的部分功能,重者会引发船舶的海难事故,造成难以估量的生命和财产损失。商船的锅炉故障往往会造成灾难性的后果,特别是对于船舶机械制造商、海事工程师和其他相关人员来说,锅炉故障是个相当棘手的问题。收集整理船用锅炉的失效模式,逐一评估它们的风险等级,是航运企业及其归管机构面临的一个重要现实问题,为制订船用锅炉机械维护、环境控制和安全评估的操作规程和法规提供科学依据,从根本上提高船用锅炉的安全可靠性。本文在系统回顾海运安全机构事故报告的基础上,归纳出船用锅炉的30种主要失效模式。随后,向有关航运公司的一线船员发出了问卷调查,征询这些失效模式的发生频度、损失程度和失效可检测度。对于每项询问内容,受访船员只能从问卷提示的10个等级中勾选一个。由于问卷提示的等级本身具有模糊性,收集的统计数据也具有一定的不确定度。本文开发了一套基于规则的模糊逻辑系统的模糊集方法,利用模糊的问卷统计数据对以上30种失效模式的风险逐一定量评估。结果表明,“燃油燃气管道泄漏”失效模式的风险等级最高,其次是“水汽局部侵蚀”,以及“余烬起火”失效模式。在风险评估过程中,前后共采用了三种基函数,研究发现高斯基函数比三角基函数和梯形基函数更好,适合于定量风险评估。另外,对于最高风险等级的“燃油燃气管道泄漏”失效模式,还开展了敏感度分析,计算考察了该失效模式的风险值对原始输入的发生频度、损失程度和失效可检测度等参数中包含的不确定度的敏感程度。本文的风险评估方法具有很强的普遍适用性,预期能广泛地应用于各类海运系统的定量风险评估。因此,本文的理论可以用来帮助业内人员提升安全意识,巩固安全防线。建议船员、锅炉操作员、船舶公司、制造商、船东、海事局等业内人士都能了解这类安全隐患,防微杜渐。本文的研究结果有助于提高船用锅炉的可靠性和安全性,减轻因锅炉失效而造成的生命和财产损失。

关键词：风险评估船用锅炉失效模式模糊专家系统机械操作海运事故海事安全性

Patents and intellectual property in orthopaedics and arthroplasty

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World Journal of Orthopedics 2020年第1期11卷 1-9页

作者： Chika Edward Uzoigwe ahmed shoaib Department of Medicine Harcourt HouseSheffield S101DGUnited Kingdom Department of Trauma and Orthopaedics Huddersfield Royal InfirmaryHuddersfield HD33EAUnited Kingdom

The provision of musculoskeletal services comes at a *** is,in part,due to the expense of patent-protected orthopaedic ***,patents have a finite *** of the most successful implants are now beginning to *** will be exposed to competition from generic but equivalent *** net effect is potentially a dramatic diminution in *** company,Orthimo,has taken advantage of this and begun manufacturing generic implants with identical design specifications to the most bio-durable hip *** will ultimately have a radical impact upon musculoskeletal healthcare provision with regard to cost and *** expiration of drug patents,with the subsequent use of generic drugs saves£7.1 billion annually in the United Kingdom and$254 billion in the *** suggest the introduction of equivalent implants could result in an annual cost saving to the United Kingdom National Health Service of£120 *** property remains an enigmatic area of *** encompasses anodyne principles that seek to protect innovation but are open to manipulation and *** last decade has seen the emergence of undesirable practices in the medical industry such as"patent trolling".Here we explore patents and their repercussions for musculoskeletal care.

关键词： Patent Arthroplasty Patent trolling Implant approval Intellectual property Health care costs

Augmenting IoT Intrusion Detection System Performance Using Deep Neural Network

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Computers, Materials & Continua 2023年第1期74卷 1351-1374页

作者： Nasir Sayed Muhammad shoaib Waqas ahmed Sultan Noman Qasem Abdullah M.Albarrak Faisal Saeed Department of Computer Science Islamia College PeshawarPeshawar25120Pakistan Department of Computer Science CECOS University of IT and Emerging SciencesPeshawar25000Pakistan Department of Electrical Engineering HITEC University TaxilaTaxila47080Pakistan Computer Science Department College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia DAAI Research Group Department of Computing and Data ScienceSchool of Computing and Digital TechnologyBirmingham City UniversityBirminghamB47XGUK

Due to their low power consumption and limited computing power,Internet of Things(IoT)devices are difficult to ***,the rapid growth of IoT devices in homes increases the risk of *** detection systems(IDS)are commonly employed to prevent *** systems detect incoming attacks and instantly notify users to allow for the implementation of appropriate *** have been made in the past to detect new attacks using machine learning and deep learning techniques,however,these efforts have been *** this paper,we propose two deep learning models to automatically detect various types of intrusion attacks in IoT ***,we experimentally evaluate the use of two Convolutional Neural Networks(CNN)to detect nine distinct types of attacks listed in the NF-UNSW-NB15-v2 *** accomplish this goal,the network stream data were initially converted to twodimensional images,which were then used to train the neural network *** also propose two baseline models to demonstrate the performance of the proposed ***,both models achieve high accuracy in detecting the majority of these nine attacks.

关键词： Internet of things intrusion detection system deep learning convolutional neural network supervised learning

Multi-Elemental Chemostratigraphy,Sequence Development,Depositional History,and Environmental Importance of Early Eocene Red Beds(Kuldana Formation)in NW Himalayas,Pakistan

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Journal of Earth Science 2024年第2期35卷 349-375页

作者： Amir Shahzad George Kontakiotis Thierry Adatte Khawaja shoaib ahmed Muhammad Tayyib Riaz Hammad Tariq Janjuhah Evangelia Besiou Institute of Geology University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Historical Geology-Paleontology Faculty of Geology and GeoenvironmentSchool of Earth SciencesNational and Kapodistrian University of AthensPanepistimiopolisZografou15784Greece Institute of Earth Sciences(ISTE) University of LausanneLausanneCH-1015Switzerland Department of Geology Shaheed Benazir Bhutto UniversitySheringalPeshawar18050Pakistan

The Eocene Kuldana Formation(KF)in the Yadgar area of Pakistan,comprises a diverse range of sedimentary facies,including variegated red beds of shales,mudstones,and sandstones,as well as interbedded limestone and *** this study,we conducted an integrated micropaleontological,sedimentological,mineralogical,and geochemical investigation to determine the depositional setting,biochronology,provenance,and paleoclimate of the *** study identified six lithofacies and six microfacies,which indicate a variety of environments ranging from floodplains and channels to the margins and shallow marine *** nannofossil biostratigraphy places the KF in the Early Eocene,more precisely the NP10 zone(Ypresian),and the fossil zone of benthic foraminifera classifies the study section as the Shallow Benthic Zone SBZ-8(Middle Ilerdian 2).In terms of petrography,the KF sandstone was classified as litharenite and feldspathic litharenite,while the QtFL diagram suggests a recycled *** proxies indicate an oxidizing environment,a high-to-low regular sedimentation rate,moderate-to-intense chemical weathering in the source region,and a warm-humid to dry climate during the deposition of ***,the findings suggest that the deposition of KF marks the end of Neo-Tethys due to the Early Eocene Indian–Kohistan collision and that the uplifting of the Himalayas provided the source for the deposition of KF in the foreland *** study provides new insights into the depositional environment,biochronology,provenance,and paleoclimate of KF,and highlights the potential for red beds as reliable indicators of oxygenation levels in proximity to mineral deposits.

关键词： sedimentary microfacies Paleocene–Eocene thermal maximum stratigraphic correlations paleoenvironmental reconstruction nannofossils paleontology

Molecular mechanisms of growth depression in broiler chickens(Gallus Gallus domesticus)mediated by immune stress:a hepatic proteome study

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1498-1516页

作者： Aijuan Zheng Anrong Zhang Zhimin Chen shoaib ahmed Pirzado Wenhuan Chang Huiyi Cai Wayne L.Bryden Guohua Liu Key Laboratory of Feed Biotechnology of Ministry of Agriculture and Rural Affairs Institute of Feed ResearchChinese Academy of Agricultural SciencesNo.12 Zhongguancun south streetHaidian districtBeijing 100081China School of Agriculture and Food Sciences University of QueenslandGattonQLD 4343Australia

Background:Immunological stress decreases feed intake,suppresses growth and induces economic ***,the underlying molecular mechanism remains ***-free liquid chromatography and mass spectrometry(LC-MS)proteomics techniques were employed to investigate effects of immune stress on the hepatic proteome changes of Arbor Acres broilers(Gallus Gallus domesticus)challenged with Escherichia coli lipopolysaccharide(LPS).Results:Proteomic analysis indicated that 111 proteins were differentially expressed in the liver of broiler chickens from the immune stress *** these,28 proteins were down-regulated,and 83 proteins were up-regulated in the immune stress *** analysis showed that immune stress upregulated the expression of hepatic proteins involved in defense function,amino acid catabolism,ion transport,wound healing,and hormone ***,immune stress increased valine,leucine and isoleucine degradation ***:The data suggests that growth depression of broiler chickens induced by immune stress is triggered by hepatic proteome alterations,and provides a new insight into the mechanism by which immune challenge impairs poultry production.

关键词： Broiler chickens Hepatic proteome Immune stress Lipopolysaccharide

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

Reversible and irreversible adsorption of bare and hybrid silica nanoparticles onto carbonate surface at reservoir condition

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Petroleum 2020年第3期6卷 277-285页

作者： Zain-UL-Abedin Arain Sarmad Al-Anssari Muhammad Ali shoaib Memon Masood ahmed Bhatti Christopher Lagat Mohammad Sarmadivaleh Department of Petroleum Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin University26 Dick Perry Avenue6151KensingtonAustralia Department of Chemical Engineering College of EngineeringUniversity of BaghdadBaghdadIraq School of Engineering Edith Cowan University270 Joondalup DriveJoondalupWA6027Australia Premier Oilfield Solutions Australia

Realistic implementation of nanofluids in subsurface projects including carbon geosequestration and enhanced oil recovery requires full understanding of nanoparticles(NPs)adsorption behaviour in the porous *** physicochemical interactions between NPs and between the NP and the porous media grain surface control the adsorption behavior of *** study investigates the reversible and irreversible adsorption of silica NPs onto oil-wet and water-wet carbonate surfaces at reservoir *** carbonate sample was treated with different concentrations of silica nanofluid to investigate NP adsorption in terms of nanoparticles initial size and hydrophobicity at different temperatures,and *** behaviour and the reversibility of NP adsorption onto carbonate surfaces was measured using dynamic light scattering(DLS),scanning electron microscope(SEM)images,energy dispersive X-ray spectroscope(EDS),and atomic force microscope(AFM)*** show that the initial hydrophilicity of the NP and the carbonate rock surface can influence the NPs adsorption onto the rock ***,oppositely charged NP and rock surface are attracted to each other,forming a mono or multilayers of NPs on the *** conditions including pressure and temperature have shown minor influence on nano-treatment ***,DLS measurement proved the impact of hydrophilicity on the stability and adsorption trend of *** was also confirmed by SEM ***,AFM results indicated that a wide-ranging adsorption scenario of NPs on the carbonate surface *** results were obtained from the EDS *** study thus gives the first insight into NPs adsorption onto carbonate surfaces at reservoirs conditions.

关键词： Nanofluid Silica nanoparticles Wettability Contact angle Surface treatment Adsorption Salinity Carbonate reservoir Carbonate

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天然软黏土的屈服行为与本构模型研究

天然软黏土的屈服行为与本构模型研究

作者： shoaib ahmed 江苏大学

学位级别：硕士

中国许多大型的城市和邻近的“一带一路”国家基础设施都是建造在软土地基上的。软黏土往往是在复杂的沉积和后沉积过程中形成土结构性,研究应力状态、应力历史及其加卸载路径之间的关系具有挑战性。在工程设计中,采用先进的仪器设备来... 详细信息

中国许多大型的城市和邻近的“一带一路”国家基础设施都是建造在软土地基上的。软黏土往往是在复杂的沉积和后沉积过程中形成土结构性,研究应力状态、应力历史及其加卸载路径之间的关系具有挑战性。在工程设计中,采用先进的仪器设备来研究土体的本构模型,是确定土体受力变形特性的必要步骤,但是目前开展试验研究软黏土土的屈服行并建立精确描述的本构模型还比较少。基于此,本文对典型的软黏土试样开展了系统的室内试验研究,分析了软黏土屈服行为并建立了相应的弹塑性本构模型来准确描述其受力变形特性。高质量的原状土样取自中国连云港地区,采用全自动TKA型应力路径三轴仪对原状土样进行了测试。通过开展一系列应力路径试验,研究了软黏土的屈服行为并详细揭示了应力路径对其屈服特性的影响。试验获得原状土的初始屈服面与重塑土的屈服面显著不同。原状土的应力-应变曲线具有屈服特性,初始屈服轨迹为沿着K线对称的倾斜椭圆,可以描述土体沉积过程中产生的原生组构各向异性。将所得的屈服面与现有的Nakano模型进行了比较,表明Nakano模型可以很好地描述试验确定的初始屈服特性。由于Nakano模型并不能反映土体后继屈服过程屈服面的旋转。因此,本文基于应力路径试验提出了修正的屈服面方程,以描述结构性软土的初始屈服特性以及结构性逐渐屈服引起的屈服面旋转。基于修正的屈服面方程建立的弹塑性本构模型主要包含七个独立参数(M,k,n,η ,p￠,l,e或e),其中M,k,n为原修正剑桥模型的参数;p￠表征初始结构屈服面的大小,反映结构性的影响;η 表示受到初始各向异性影响的天然土初始屈服面的对称轴所对应的应力比;参数l,p￠,e描述初始屈服后天然土的压缩特性。通过对比模型计算值与已发表的Bothkennar黏土试验实测值,验证了模型的有效性。

关键词：应力路径软黏土土结构性各向异性屈服行为本构模型