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Theory and Semi-Analytical Study of Micropolar Fluid Dynamics through a Porous Channel

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1473-1486页

作者： Aziz Khan sana ullah Kamal Shah Manar A.Alqudah Thabet Abdeljawad Fazal Ghani Department of Mathematics and Sciences Prince Sultan UniversityP.O.Box 66833Riyadh11586Saudi Arabia Department of Mathematics Abdul Wali Khan UniversityMardanP.O.Box 23200Khyber Pakhtunkhwa23200Pakistan Department of Mathematics University of MalakandChakdara Dir(L)Khyber Pakhtunkhwa18000Pakistan Department of Mathematical Sciences Faculty of SciencesPrincess Nourah bint Abdurahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Medical Research China Medical UniversityTaichung40402Taiwan

In this work,We are looking at the characteristics of micropolar flow in a porous channel that’s being driven by suction or injection.The working of the fluid is described in the flowmodel.We can reduce the governing nonlinear partial differential equations(PDEs)to a model of coupled systems of nonlinear ordinary differential equations using similarity variables(ODEs).In order to obtain the results of a coupled system of nonlinear ODEs,we discuss a method which is known as the differential transform method(DTM).The concern transform is an excellent mathematical tool to obtain the analytical series solution to the nonlinear ODEs.To observe beast agreement between analytical method and numerical method,we compare our result with the Rung-Kutta method of order four(RK4).We also provide simulation plots to the obtained result by using Mathematica.Onthese plots,we discuss the effect of different parameters which arise during the calculation of the flow model equations.

关键词： Mass transfer micropolar flow porous channel similarity variables differential transform method

Recent Advances in Design Strategies and Multifunctionality of Flexible Electromagnetic Interference Shielding Materials

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Nano-Micro Letters 2022年第5期14卷 122-152页

作者： Junye Cheng Chuanbing Li Yingfei Xiong Huibin Zhang Hassan Raza sana ullah Jinyi Wu Guangping Zheng Qi Cao Deqing Zhang Qingbin Zheng Renchao Che School of Science and Engineering The Chinese University of Hong KongShenzhen 518172People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsDepartment of Materials ScienceFudan UniversityShanghai 200438People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096People’s Republic of China

With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential role.Meanwhile,the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding applications.Hitherto,a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been developed.In this review,we not only introduce the recent development of flexible EMI shielding materials,but also elaborate the EMI shielding mechanisms and the index for"green EMI shielding"performance.In addition,the construction strategies for sophisticated multifunctionalities of flexible shielding materials are summarized.Finally,we propose several possible research directions for flexible EMI shielding materials in near future,which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials.

关键词： Flexible shielding materials Green shielding index Multifunctionalities EMI shielding mechanism

The coupling of sand with ZVI/oxidants achieved proportional and highly efficient removal of arsenic

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 29-39页

作者： sana ullah Xuejun Guo Xiaoyan Luo Xiangyuan Zhang Yameng Li Ziyu Liang State Key Laboratory of Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Department of Environmental and Conservation Sciences University of Swat19200Pakistan

The coupling of zero-valent iron(ZVI)with common oxidants has recently achieved very rapid and highly efficient removal of Heavy metals from wastewater.However,the uniform activation of ZVI throughout the column and the proportional removal of target contaminants are urgently required for the prevention of premature filter clogging and the extension of the effective column operational time.In this study,we successfully achieved this objective by simply doping granular sand with ZVI at appropriate weight ratios.When pure ZVI packed column was spiked with oxidants,the majority of As trapping occurred between the column inlet and the first sampling point.In a packed column with a 1:20 mixture of ZVI and sand,the average As removal efficiency was 36(1st),13.1(2nd),18.5(3rd),19.2(4th)and 5.9%(5th outlet).The overall arsenic removal performance of the composite filling system of ZVI/sand was equally as efficient as that of the previous pure ZVI-packed system.Moreover,the leaching of Fe was significantly reduced with an increased sand ratio,resulting in clearer water with less turbidity.The results of X-ray photoelectron spectroscopy(XPS)demonstrated that more than 54%of the arsenic was reduced to As(III).X-ray diffraction(XRD)and scanning electron microscopy(SEM)confirmed the extensive corrosion of the ZVI surface,which resulted in various species of iron oxyhydroxides responsible for the highly efficient sequester of arsenic through reduction,adsorption,and coprecipitation.

关键词： Arsenic ZVI Sand Oxidants Fixed-bed Column Removal

Rapid and long-effective removal of broad-spectrum pollutants from aqueous system by ZVI/oxidants

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Frontiers of Environmental Science & Engineering 2020年第5期14卷 147-156页

作者： sana ullah Xuejun Guo Xiaoyan Luo Xiangyuan Zhang Siwen Leng Na Ma Palwasha Faiz State Key Laboratory of Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Department of Environmental and Conservation Sciences University of SwatMingora 19200Pakistan

Zero-valent iron(ZVI)technology has recently gained significant interest in the efficient sequestration of a wide variety of contaminants.However,surface passivation of ZVI because of its intrinsic passive layer would lead to the inferior reactivity of ZVI and its lower efficacy in contaminant removal.Therefore,to activate the ZVI surface cheaply,continuously,and efficiently is an important challenge that ZVI technology must overcome before its wide-scale application.To date,several physical and chemical approaches have been extensively applied to increase the reactivity of the ZVI surface toward the elimination of broad-spectrum pollutants.Nevertheless,these techniques have several limitations such as low efficacy,narrow working pH,eco-toxicity,and high installation cost.The objective of this mini-review paper is to identify the critical role of oxygen in determining the reactivity of ZVI toward contaminant removal.Subsequently,the effect of three typical oxidants(H2O2,KMnO4,and NaClO)on broad-spectrum contaminants removal by ZV1 has been documented and discussed.The reaction mechanism and sequestration efficacies of the ZVI/oxidant system were evaluated and reviewed.The technical basis of the ZVI/oxidant approach is based on the half-reaction of the cathodic reduction of the oxidants.The oxidants commonly used in the water treatment industry,i.e.,NaClO,O3,and H2O2,can be served as an ideal coupling electron receptor.With the combination of these oxidants,the surface corrosion of ZVI can be continuously driven.The ZVI/oxidants technology has been compared with other conventional technologies and conclusions have been drawn.

关键词： Zero-Valent Iron(ZVI) Oxidants Heavy Metals(HMs) Metalloids Nitrate,Phosphate

A Review of Wireless Body Area Networks for Medical Applications

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International Journal of Communications, Network and System Sciences 2009年第8期2卷 797-803页

作者： sana ullah Pervez KHAN Niamat ullah Shahnaz SALEEM Henry HIGGINS Kyung Sup KWAK 不详

Recent advances in Micro-Electro-Mechanical Systems (MEMS) technology, integrated circuits, and wireless communication have allowed the realization of Wireless Body Area Networks (WBANs). WBANs promise unobtrusive ambulatory health monitoring for a long period of time, and provide real-time updates of the patient’s status to the physician. They are widely used for ubiquitous healthcare, entertainment, and military applications. This paper reviews the key aspects of WBANs for numerous applications. We present a WBAN infrastructure that provides solutions to on-demand, emergency, and normal traffic. We further discuss in-body antenna design and low-power MAC protocol for a WBAN. In addition, we briefly outline some of the WBAN applications with examples. Our discussion realizes a need for new power-efficient solu-tions towards in-body and on-body sensor networks.

关键词： Wireless Body Area Networks Low Power MAC Body Sensor Networks BSN WBAN

PAIgG and PAIgM levels in secondary dengue virus infections lead to thrombocytopenia in patients from KP, Pakistan

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Asian Pacific Journal of Tropical Biomedicine 2015年第10期5卷 801-805页

作者： Ibrar Alam Said Hassan Iftikhar Alam Rahmat Gul Farhad AliIjaz Ali sana ullah Imtiaz Ali Khan Aasif Awan Department of Biotechnology Bacha Khan University Charsadda Institute of Biotechnology and Genetic Engineering(IBGE) The University of Agriculture Center of Biotechnology and Microbiology University of Peshawar Department of Human Nutrition and Dietetics Bacha Khan University Charsadda Department of Zoology University of Peshawar Department of Entomology The University of Agriculture

Objective: To understand the impact of platelet associated immunoglobulin G(PAIg G)/platelet associated immunoglobulin M(PAIg M) on severity of dengue virus infection leading to thrombocytopenia.Methods: In this study we examined a total of 52 patients who were having secondary infection of dengue in acute phase by using competitive ELISA.Results: A decrease in the platelet count was observed at the acute phase of infection while all along the recovery stage the count of platelet was significantly increased. A significant decrease was observed in PAIg G and PAIg M in these subjects. Inverse correlation was found between platelets count and PAIg G/PAIg M among the subjects studied. In the platelets elution from ten subjects, anti-dengue virus immunoglobulin G and immunoglobulin M were observed. PAIg G and PAIg M with inclined levels were higher in dengue hemorrhagic fever than the classical dengue fever. In the development of dengue hemorrhagic fever PAIg M inclined level was independently associated with high specificity, showing a possible indication of dengue hemorrhagic fever.Conclusions: This study suggests that in secondary dengue virus infection, the PAIg G and PAIg M levels, and the activity of anti-dengue virus play key roles, both in the development and severity of the disease.

关键词： dengue Pakistan immunoglobulin hemorrhagic severit

无人机组网遥感实时任务观测的冗余容错控制方案

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地球信息科学学报 2019年第4期21卷 552-559页

作者： sana ullah 晏磊冯朝晖赵海盟孙逸渊赵红颖北京大学地球与空间科学学院遥感与地理信息系统研究所北京100871

中小型无人机(UAV)越来越多地应用于各种实时静态和动态任务中,已成为对人类非常有用的辅助工具。适合无人机在各种条件下进行监视和测量的因素有很多,但无人机在执行不同的实时任务时仍会受到各种挑战,且一旦在任务执行过程中任何一个... 详细信息

中小型无人机(UAV)越来越多地应用于各种实时静态和动态任务中,已成为对人类非常有用的辅助工具。适合无人机在各种条件下进行监视和测量的因素有很多,但无人机在执行不同的实时任务时仍会受到各种挑战,且一旦在任务执行过程中任何一个约束的及时响应缺失,将会影响任务的总体结果,导致整个任务部分或完全失败,在实际中很难建立完美系统。因此,在系统中引入冗余容错来最小化故障概率并增强其鲁棒性非常重要。其中,根本问题是随着系统复杂性的增加,除非对其采取补偿措施,否则其可靠性会急剧下降。冗余容错是通过添加一个或多个模块(通常采用并行配置)作为备份来引入冗余。为了提高极端条件下航空遥感任务无人机网络系统的鲁棒性和成功率,本文将基于冗余的容错控制技术引入无人机网络设计中,确定了不同限制条件下的最佳网络解决方案。组网设计是在不同观测条件下的遥感任务如"大尺度生态监测"、"中尺度洪灾监测"、"小尺度安全监测"中,通过同步监控进行主动合作的包括多个无人机的网络。多无人机网络作为冗余容错体系结构时可以通过添加多个无人机作为备份使得系统可以容错,而无人机在不同极端条件下的位置和视角则可以作为冗余容错的场景设置。当组网方案中的无人机位置和视角超过设定的阈值时可以被认为是故障的,其将被分离并不考虑进一步分析。通过以上方式,无人机网络可以在极端条件下得到组网控制方案的有效输出,进而保证遥感观测任务的顺利进行。

关键词：无人机组网生态监测灾害监测安全监控冗余容错

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基于动态极坐标参数化的遥感影像匹配方法

地球信息科学学报 2019年第10期21卷 1586-1593页

作者：孙嘉玉左正康孙逸渊 sana ullah 张瑞华赵海盟空间信息集成与3S工程应用北京市重点实验室(北京大学) 北京100871 桂林航天工业学院广西高校无人机遥测重点实验室桂林541004

图像匹配作为三维重建至关重要的环节,其精度直接影响了平差优化、正射校正等模块的精度。对于城镇、农场等特征密集型区域,特征距离小,相似性强,易于匹配图像;而针对草地、沙漠等特征不明显区域,特征距离大,如果使用特征点匹配的方法,... 详细信息

图像匹配作为三维重建至关重要的环节,其精度直接影响了平差优化、正射校正等模块的精度。对于城镇、农场等特征密集型区域,特征距离小,相似性强,易于匹配图像;而针对草地、沙漠等特征不明显区域,特征距离大,如果使用特征点匹配的方法,严格阈值下难以获得足够数量的匹配对,放宽阈值又将引入较多误匹配对,这也是导致稀疏点云不够均匀的原因之一。在此场景下,本文提出了基于动态极坐标参数化的无人机正视影像匹配算法,首先对图像做极坐标参数变化,采用动态策略解决极轴方向采样不均匀的问题,使用最小二乘法对得到的极坐标影像对做位移方向上的匹配,匹配后得到的旋转量和平移量,将该结果和SIFT算法的结果做比较。本文设计了2组实验,即参数已知的解算实验和参数未知的解算实验,且每组实验进行3次。在同等配置的计算机上,对两张7360像素×5400像素,32位的影像,本文方法的位姿解算时间相比SIFT的时间减少约57%,二者求得的位姿差通常小于1%。结论表明二者的结果在精度上表现相当,在时间上明显优于SIFT算法,具有实际的应用价值。

关键词：无人机极坐标遥感影像匹配三维重建光束法平差参数化影像拼接

协同性的介电损耗和磁损耗使少层WS2纳米片与NiO纳米粒子的杂化物具有优异的微波吸收性能

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Science Bulletin 2020年第2期65卷 138-146,88页

作者：张德庆熊英飞程俊业柴吉星刘婷婷巴学巍 sana ullah 郑广平严明曹茂盛 School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong KongChina Department of Materials Science and Engineering and Shenzhen Key Laboratory for Additive Manufacturing of High-performance MaterialsSouthern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

由于高的比表面、层状结构以及特殊的电子结构,二硫化钨在电磁波吸收领域受到了科研人员的广泛关注.然而,二硫化钨有限的电磁吸收能力和带宽还有待进一步的改进,以满足其作为电磁吸收材料的实际应用.本研究采用水热法制备了具有异质结构... 详细信息

由于高的比表面、层状结构以及特殊的电子结构,二硫化钨在电磁波吸收领域受到了科研人员的广泛关注.然而,二硫化钨有限的电磁吸收能力和带宽还有待进一步的改进,以满足其作为电磁吸收材料的实际应用.本研究采用水热法制备了具有异质结构的WS2/NiO杂化材料,并将其发展成为电磁波吸收基体.在4.27 mm厚度下,掺20%NiO杂化物材料的最大反射损失可达-53.31 dB;RL值小于-10 dB的带宽范围为4.54~18 GHz,此时吸波材料的厚度在3.5~5.5 mm.研究结果表明,WS2/NiO杂化材料优异的吸波性能是由于磁性Ni O的加入,形成了WS2和Ni O的异质界面,从而引起杂化材料协同的磁损耗和介电损耗,这为设计优异的吸波材料以及实际的应用开辟了新的途径.

关键词： 2D nanosheets WS2/NiO hybrids Hetero-structures Microwave absorption