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Influence of Brownian Motion, Thermophoresis and Magnetic Effects on a Fluid Containing Nanoparticles Flowing over a Stretchable Cylinder

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Fluid Dynamics & Materials Processing 2024年第3期20卷 525-536页

作者： Aaqib Majeed Ahmad zeeshan Department of Mathematics The University of FaisalabadFaisalabad38000Pakistan Department of Mathematics and Statistics FBASInternational Islamic University IslamabadIslamabad44000Pakistan

The influence of Brownian motion and thermophoresis on a fluid containing nanoparticles flowing over a stretchable cylinder is *** classical Navier-Stokes equations are considered in a porous *** addition,the Lorentz force is taken into *** controlling coupled nonlinear partial differential equations are transformed into a system of first order ordinary differential equations by means of a similarity *** resulting system of equations is solved by employing a shooting approach properly implemented in *** evolution of the boundary layer and the growing velocity is shown graphically together with the related profiles of concentration and *** magnetic field has a different influence(in terms of trends)on velocity and concentration.

关键词： Mixed convection Brownian motion heat transfer porous surface velocity slip

Mg-Gd-Y-Zn-Zr合金的阻燃性能研究

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Mg-Gd-Y-Zn-Zr合金的阻燃性能研究

作者：郑山（muhammad zeeshan Farooq）哈尔滨工业大学

学位级别：硕士

镁及镁合金在航空航天、汽车交通等领域具有广泛的应用前景。然而,镁合金的阻燃性较差,从而限制了其在很多领域的应用,比如民用飞机和其他的航空部件。近来,很多相关的研究旨在通过改善镁合金表层氧化膜的致密性,以达到提高镁合金的抗... 详细信息

镁及镁合金在航空航天、汽车交通等领域具有广泛的应用前景。然而,镁合金的阻燃性较差,从而限制了其在很多领域的应用,比如民用飞机和其他的航空部件。近来,很多相关的研究旨在通过改善镁合金表层氧化膜的致密性,以达到提高镁合金的抗氧化性和阻燃性的目的。在诸多技术手段中,合金化是常用的改变表面氧化物结构的方法之一。本课题主要研究Mg-Gd-Y-Zn-Zr合金的阻燃性能。通过改变合金化元素Gd、Y和Zn的含量,并对不同成分合金进行阻燃性能测试,揭示了合金元素对镁合金阻燃性能的影响。此外,本论文还研究了热处理及挤压变形对Mg-Gd-Y-Zn-Zr合金的阻燃性和氧化性能的影响。本论文采用电弧炉试验方法测量了具有不同成分的Mg-Gd-Y-Zn-Zr合金的着火点温度。研究发现,含有6wt%Y的合金具有优异的阻燃性能。该合金在901℃的温度加热30min后仍然不发生燃烧,而含有0wt%Y和1wt%Y的合金的着火温度分别为696℃和768℃。这些结果表明Y元素可以有效地提高镁合金的阻燃性。随着Y元素含量的增大,合金的着火点温度得到了明显的提升。然而,需要说明的是,着火点测试的结果会受具体的测试细节的影响。火焰测试能够直接研究材料在火焰中的行为,因此可以有效地研究镁合金在飞机火灾事故中的燃烧行为。为了研究Mg-Gd-Y-Zn-Zr合金的氧化行为,本论文采用X射线衍射(XRD),扫描电子显微镜(SEM)对氧化膜的相组成进行了研究。研究结果表明,合金表面的致密氧化膜是由Mg O、YO、Gd O、Zn O和Zr O组成的。通过对具有不同成分的Mg-Gd-Y-Zn-Zr合金进行热处理,并对热处理后的合金进行阻燃性测试,发现热处理能有效提高镁合金的阻燃性。其中,含有6wt%Y合金的着火点从901℃提高到了936℃。通过XRD和SEM分析,发现热处理合金的致密氧化膜也是由Mg O、YO、Gd O、Zn O和Zr O组成的。此外,本论文还研究了Mg-7Gd-2Y-0.6Zn-0.6Zr(wt.%)合金不同状态的阻燃性。通过阻燃性测试发现,该合金在铸态下的着火温度为748℃。经过固溶处理后,其着火温度略有下降,742℃。随后的时效处理使合金的着火温度提高至760℃。该合金经过挤压变形后,其着火温度为622℃,而时效处理可以使挤压态合金的着火温度提高至633℃。

关键词：稀土镁合金阻燃性热处理挤压氧化行为

Synthesis and Charcterization of Silane Crosslinked Hydrogel to pH Sensitive Study

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American Journal of Analytical Chemistry 2024年第5期15卷 165-176页

作者： muhammad Awais Shahid Abdul Haseeb Tahir zeeshan Ahmad muhammad Arslan Department of Physics The University of Lahore Lahore Punjab Pakistan Department of Chemistry Minhaj University Lahore Lahore Pakistan Department of Physics University of Punjab Lahore Pakistan

Eco-friendly and biodegradable novel hydrogel were prepared by blending and solution casting method. The designed hydrogel is based on chitosan/ PEG600/Gurgam with carbon nanofiller along silane crosslinked (TEOS) with pH sensitive response to controlled release of drug in biomedical materials and agriculture industry. The various concentration of carbon nanofiller is used to analyze its effect on the fabricated hydrogel characteristics by using FTIR, SEM, TGA, swelling studies (water, buffer and ionic solution). Spectra of FTIR reflected both established and newly developed groups (like hydrogel). COOH group presence is clearly observed in this range in the carbon filler reinforced hydrogel. The SEM micrographs show that CPG0.003 had a collection of polysaccharide chains as thin helices, which is attributed to the increase in the size of porosity. TGA shows to increase concentration of nanofiller enhanced the thermal stability of the designed hydrogels at temperature 25˚C to 550˚C mass loss percentage decrease upto 20% and increase thermal stability. This pH response made these resultant hydrogels as fruitful competitor against the many reported controlled release application.

关键词： Chitosan Guargum Hydrogel Carbon Nano Filler Silane Cross Linker pH Sensitive

Risk of infection with arboviruses in a healthy population in Pakistan based on seroprevalence

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Virologica Sinica 2024年第3期39卷 369-377页

作者： Shengyao Chen muhammad Saqib Hafiz Sajid Khan Yuan Bai Usman Ali Ashfaq muhammad Khalid Mansoor Abulimti Moming Jing Liu Min Zhou Saifullah Khan Niazi Qiaoli Wu Awais-Ur-Rahman Sial Shuang Tang muhammad Hassan Sarfraz Aneela Javed Sumreen Hayat Mohsin Khurshid Iahtasham Khan muhammad Ammar Athar zeeshan Taj Bo Zhang Fei Deng Ali Zohaib Shu Shen Key Laboratory of Virology and National Virus Resource Center Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Faculty of Veterinary Science University of Agriculture FaisalabadFaisalabad 38040Pakistan The Children's Hospital Faisalabad 38000Pakistan Department of Bioinformatics and Biotechnology Government College University FaisalabadFaisalabad 38000Pakistan f Department of Microbiology Faculty of Veterinary and Animal SciencesThe Islamia University of BahawalpurBahawalpur 63100Pakistan Hubei Jiangxia Laboratory Wuhan 430200China Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China Armed Forces Institute of Pathology(AFIP) Rawalpindi 46000Pakistan Department of Clinical Studies Faculty of Veterinary&Animal SciencesPir Mehr Ali Shah Arid Agriculture UniversityRawalpindi 46300Pakistan Institute of Microbiology Government College University FaisalabadFaisalabad 38000Pakistan l Atta-ur-Rahman School of Applied Biosciences National University of Science and TechnologyIslamabad 44000Pakistan Department of Clinical Sciences University of Veterinary and Animal SciencesLahore Sub-campusJhang 35200Pakistan Department of Molecular Pathology National Medical Center DHA Phase 1Karachi 75500Pakistan

Infectious diseases caused by arboviruses are a public health concern in ***,studies on data prevalence and threats posed by arboviruses are *** study investigated the seroprevalence of arboviruses in a healthy population in Pakistan,including severe fever with thrombocytopenia syndrome virus(SFTSV),Crimean-Congo hemorrhagic fever virus(CCHFV),Tamdy virus(TAMV),and Karshi virus(KSIV)based on a newly established luciferase immunoprecipitation system(LIPS)assays,and Zika virus(ZIKV)by enzyme-linked immunosorbent assays(ELISA).Neutralizing activities against these arboviruses were further examined from the antibody positive *** results showed that the seroprevalence of SFTSV,CCHFV,TAMV,KSIV,and ZIKV was 17.37%,7.58%,4.41%,1.10%,and 6.48%,respectively,and neutralizing to SFTSV(1.79%),CCHFV(2.62%),and ZIKV(0.69%)were identified,as well as to the SFTSV-related Guertu virus(GTV,0.83%).Risk factors associated with the incidence of exposure and levels of antibody response were ***,co-exposure to different arboviruses was demonstrated,as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing ***,individuals aged40 years,and outdoor workers had a high risk of exposure to *** these results reveal the substantial risks of infection with arboviruses in Pakistan,and indicate the threat from co-exposure to multiple *** findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.

关键词： Arbovirus Pakistan Seroprevalence Tick-borne virus Mosquito-borne virus

Design and Synthesis of NiO@Co_(3)O_(4)@ZSM-5 Heterogeneous Multitask Hollow Structures for Tandem Catalysis

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Chemical Research in Chinese Universities 2024年第3期40卷 529-535页

作者： muhammad Waqas Interdisciplinary Research Center for Refining and Advanced Chemicals King Fahd University of Petroleum&MineralsDhahran 31261Saudi Arabia

Precipitation and impregnation procedures unevenly distribute metals on zeolite,limiting chemical transformation in Lewis-acid,Brönsted-acid and metal-catalyzed tandem ***,heterogeneous multitask transition metals oxides@zeolites are promising catalysts for sustainable processes;nevertheless,synthesis is fascinating and ***,the construction of purposely designed multitask materials segregated in selective shells reveals the remarkable spatial organization of metals-zeolite,resulting in them being suitable for a wide range of tandem *** synthesis of multi-site catalysts begins with a universal wet chemistry approach that yields nickel oxide(NiO)***,the NiO crystals are stabilized using cationic dodecyltrimethylammonium bromide,followed by achieving cross-linking carbon growth by emulsion polymerization of glucose in hydrothermal treatment to yield uniformed NiO@carbon spheres(NiO@CSs).Next,sequential adsorption of cobalt cations and colloidal ZSM-5(1%in H_(2)O,mass fraction),followed by calcination in air,yielded NiO@cobalt oxide@zeolite denoted as NiO@Co_(3)O_(4)@ZEO hollow *** hollowing mechanism and materials segregation within shells are revealed by scanning and transmission electron microscopy,thermogravimetric analysis,and X-ray *** finding advances the rational synthesis of heterogenous core-shell hollow structures for various gas phase catalytic tandem reactions to yield valuable chemicals.

关键词： Multifunctional Core-shell hollow spheres Gas-phase reaction Valuable chemical

An integrated land change modeler and distributed hydrological model approach for quantifying future urban runoff dynamics

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Science China Earth Sciences 2024年第10期67卷 3288-3301页

作者： Asad Hussain muhammad Waseem muhammad Ajmal muhammad Atiq Ur Rehman Tariq muhammad Jiaqing XIAO Tao YANG Pengfei SHI Institute for Disaster Risk Management School of Geographical ScienceNanjing University of Information Science and TechnologyNanjing 210044China The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China Yangtze Institute for Conservation and Development Hohai UniversityNanjing 210098China College of Hydrology and Water Resources Hohai UniversityNanjing 210098China Centre of Excellence in Water Resources Engineering University of Engineering and TechnologyLahore 54890Pakistan Department of Agricultural Engineering Faculty of CivilAgricultural and Mining EngineeringUniversity of Engineering and TechnologyPeshawar 25120Pakistan

Climate and land use changes have a significant impact on the runoff generation process in urban environments, and these effects could get worse in the future. The combined contributions of these changes have increased the risk of ***, there is a need for integrated modeling to better understand the runoff variability, especially in small urban catchments. To quantify and separate the effects of land-use changes and climate change on the hydrological response of urban catchments with a distributed hydrological model(Storm Water Management Model, SWMM), this study introduces a new integrated approach based on the Machine Learning based land use change modeler and climate change scenarios under *** on supervised classification and land use change model analysis, accumulated impervious area increase from 22%(in2023) to 33%(in 2060) was observed in the study area. Furthermore, integrating this projected increase in imperviousness with future climate change into SWMM by considering three different scenarios i.e., S1(Climate Change), S2(Combined Land Use and Climate Change), and S3(Land use Change) resulted that climate change could cause an increase in runoff from 13.2% to18.3% in peak runoff and the contribution of land use could range from 9.1% to 18.6%. Similarly, in response to the coupled effects of climate and land-use change, the runoff would likely change from 24.53% to 39.66%. Conclusively, the study showed that despite climate change, intensive urban development by the substitution of impervious surfaces could also have a severe impact on the microclimate and hydrology of small catchments. Lastly, this study could provide a way forward for the future planning and management of water resources in small catchments which could be extended to larger catchments.

关键词： Climate change Land-use modeling Runoff simulation Percent Imperviousness TerrSet

Dengue: An Escalating Problem of Our Society

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Open Journal of Epidemiology 2015年第1期5卷 9-13页

作者： Faiza Naseer Attiya Nazish Rida Khan Samra Sadiq Nadia Perveen Zainab Kaleem Shaneel Kausar muhammad zeeshan Ashraf College of Pharmacy GC University Faisalabad Pakistan Department of Physiology and Pharmacology Agriculture University Faisalabad Pakistan

Dengue virus infection is more and more acknowledged as one of the world’s major escalating problems. Dengue is prevalent in most tropical and subtropical countries. To solve this problem, pharmacists need to understand the epidemiology, risk factors, clinical spectrum, diagnosis, management, prevention, and novel avenues of dengue.

关键词： Dengue Escalating Pharmacist Prevention Novel Avenues

Enhancing PDF Malware Detection through Logistic Model Trees

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Computers, Materials & Continua 2024年第3期78卷 3645-3663页

作者： muhammad Binsawad Department of Information Systems King Abdulaziz UniversityP.O.Box 80217Jeddah21589Saudi Arabia

Malware is an ever-present and dynamic threat to networks and computer systems in cybersecurity,and because of its complexity and evasiveness,it is challenging to identify using traditional signature-based detection *** study article discusses the growing danger to cybersecurity that malware hidden in PDF files poses,highlighting the shortcomings of conventional detection techniques and the difficulties presented by adversarial *** article presents a new method that improves PDF virus detection by using document analysis and a Logistic Model *** a dataset from the Canadian Institute for Cybersecurity,a comparative analysis is carried out with well-known machine learning models,such as Credal Decision Tree,Naïve Bayes,Average One Dependency Estimator,Locally Weighted Learning,and Stochastic Gradient *** traditional structural and JavaScript-centric PDF analysis,the research makes a substantial contribution to the area by boosting precision and resilience in malware *** use of Logistic Model Tree,a thorough feature selection approach,and increased focus on PDF file attributes all contribute to the efficiency of PDF virus *** paper emphasizes Logistic Model Tree’s critical role in tackling increasing cybersecurity threats and proposes a viable answer to practical issues in the *** results reveal that the Logistic Model Tree is superior,with improved accuracy of 97.46%when compared to benchmark models,demonstrating its usefulness in addressing the ever-changing threat landscape.

关键词： Malware detection PDF files logistic model tree feature selection cybersecurity

Progress in electrocatalytic nitrate reduction for green energy:Catalyst engineering,mechanisms,and techno-economic feasibility

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Journal of Energy Chemistry 2024年第8期95卷 380-406,I0009页

作者： Hafiz muhammad Adeel Sharif Hafiz muhammad Farooq Khan Sadeeq Ullah Yuwei Wang muhammad Ahmad Bo Yang Changping Li muhammad Bilal Asif Research Center for Eco-Environmental Engineering Dongguan University of TechnologyDongguan 523808GuangdongChina College of Chemistry and Engineering Shenzhen UniversityShenzhen 518060GuangdongChina FMH College of Medicine and Dentistry LahorePakistan School of Environment and Civil Engineering Research Center for Eco-Environment EngineeringDongguan University of TechnologyDongguan 523106GuangdongChina Advanced Membranes and Porous Materials Center(AMPMC) Physical Sciences and Engineering(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955Saudi Arabia

Ammonia(NH_(3))is an irreplaceable chemical that has been widely demanded to keep the sustainable development of modern ***,its industrial production consumes a huge amount of energy and releases extraordinary greenhouse gases(GHGs),leading to various environmental *** the green production of ammonia is a great challenge,which has been extensively pursued in the last *** this review,the most promising strategy,electrochemical nitrate reduction reaction(e-NO_(3)RR),is comprehensively investigated to give a complete understanding of its development and mechanism and provide guidance for future ***,owing to the complex reactions and limited selectivity,a comprehensive understanding of the mechanisms is crucial to further development and ***,NO_(3)^(-)RR is a promising strategy for simultaneous water treatment and NH_(3)production.A detailed overview of the recent progress in NO_(3)^(-)RR for NH_(3)production with nontransition and transition metal based electrocatalysts is *** addition,critical advanced techniques,future challenges,and prospects are discussed to guide future research on transition metal-based catalysts for commercial NH_(3)synthesis by NO_(3)^(-)reduction.

关键词： Nitrate reduction Electrolysis Pollution to solution Transition metal catalysts Ammonia synthesis Green energy