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Journal of Pharmaceutical Analysis 2020年第2期10卷 109-122页

作者： wajid ali khan Muhammad Balal Arain Yadollah Yamini Nasrullah Shah Tasneem Gul Kazi Stig Pedersen-Bjergaard Mohammad Tajik Department of Chemistry Abdul Wali Khan University Mardan23200KPKPakistan Department of Chemistry University of Karachi75270KarachiPakistan Department of Chemistry Tarbiat Modares UniversityP.O.Box 14115-175TehranIran National Center of Excellence in Analytical Chemistry University of SindhJamshoro76080SindhPakistan School of Pharmacy University of OsloOsloNorway

Hollow-fiber liquid-phase microextraction(HF-LPME)and electromembrane extraction(EME)are miniaturized extraction techniques,and have been coupled with various analytical instruments for trace analysis of heavy metals,drugs and other organic compounds,in recent years.HF-LPME and EME provide high selectivity,efficient sample cleanup and enrichment,and reduce the consumption of organic sol-vents to a few micro-liters per sample.HF-LPME and EME are compatible with different analytical in-struments for chromatography,electrophoresis,atomic spectroscopy,mass spectrometry,and electrochemical detection.HF-LPME and EME have gained significant popularity during the recent years.This review focuses on hollow fiber based techniques(especially HF-LPME and EME)of heavy metals and pharmaceuticals(published 2017 to May 2019),and their combinations with atomic spectroscopy,UV-VIS spectrophotometry,high performance liquid chromatography,gas chromatography,capillary elec-trophoresis,and voltammetry.

关键词： Hollow fiber liquid phase microextraction Electromembrane extraction Heavy metals Pharmaceuticals Instrumental techniques

Wellbore Stability Study in High Pressure and High Temperature Wells

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Wellbore Stability Study in High Pressure and High Temperatu...

作者： wajid ali khan 中国石油大学(北京)

学位级别：硕士

In Oil and gas industry High-Pressure and High Temperature（HPHT）is very famous term.Moving down into a deeper well having higher temperature and higher pressure,are more problematic as compared to conventional wells.In this work,some of the relevant issues are found when dealing with a setting well having HPHT.To maintain a safe and secure operation of well drilling,enough well control knowledge will be required.The selection of blowout preventer（BOP）is very considerable during the HPHT wells control.While performing the drilling operations of conventional wells,it is necessary to keep the formation pressure of a well below the fracture pressure and higher than pore pressure.This is to stop the formation fluids infiltrating the wellbore or the drilling mud into the formation.Therefore,pore pressure diagnostics play an important role to design the drilling mud and casing.By utilizing technologies of MPD ＆ UBD,we came over to reduce the numerous issues during the wellbore drilling operations.This thesis consists of seven chapters and focused on,high temperature and pressure drilling operation and well control as well.This research is being performed to discuss the most important aspects of HPHT wells.The first chapter summaries HPHT wells.This chapter also delivers information about the classification of the wells having higher pressure and higher temperature,their practices,and the industry having technological gaps related to HPHT wells.The second chapter provides knowledge about the uses of drilling fluid and criteria for the selection of drilling mud in HPHT wells.The selection and usage of the different types of drilling fluids during drilling operations in HPHT wells and the drilling fluidrelated problems are also discussed in this chapter the drilling fluid behavior and their influence on the high temperature and pressure and their rheological parameters explanation are also part of this chapter.The third chapter is about the issues related to the wellbore instability and also focused on the instability of t

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基于60°相位差电压合成型直接潮流控制器

基于60°相位差电压合成型直接潮流控制器

作者： wajid ali khan 苏州大学

学位级别：硕士

For the power flow control and effective utilization of the installed transmission and generation systems,a power flow controller "Direct power flow controller based on synthesis of two 600 phase different voltages"（DPFC-S60）is proposed.In comparison with SSSC,UPFC and STATCOM,DPFC-S60 is not utilizing any dc energy storage element therefore it avoids all the disadvantages brought by dc energy storage elements i.***.it will possibly reduce the maintenance cost,and will have low failure rate and extended life compared to the devices containing dc energy storage elements.The proposed controller has the ability to regulate the phase angle and amplitude of its output compensating voltage.The compensating voltage upon addition with the original grid voltage regulate the active and reactive power flow.DPFC-S60 is a kind of direct power flow controller（DPFC）whose compensating voltages are obtained from the synthesis of two voltages which have a phase difference of 600 between them.DPFC-S60 has no 3rd harmonic currents and voltages.DPFC-S60 has a single stage conversion circuit and is composed of an output transformer,two input transformers,six buck type ac units,two selection switches and three single phase output filters.In comparison with its input voltage the basic DPFC-S60 can regulate the phase angle of its output voltage up to 600.The 600 regulation range is extended to 3600 by employing two selection switches.The operation principle,and th circuit design is studied in detail.The regulation of grid voltage with the introduction of the compensating voltage to the grid and the variation of the compensating voltage’s phase angle and amplitude with varying duty ratios in different regulatory zones is researched in detail.An approach for the regulation of grid voltages in unbalance case has been presented.Simulations were performed using Saber simulation software to verify the theory of DPFC-S60.Simulation results for both balanced and unbalanced cases are discussed.A prototype was designed for DPFC-S60 with DSP TMS320F2

关键词： Direct power flow controller grid voltage voltage compensation amplitude adjustment phase angle regulation transmission system

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电压合成型直接潮流控制器

自动化技术与应用 2020年第6期39卷 1-5页

作者： wajid ali khan 张友军路国庆苏州大学机电工程学院江苏苏州215000

为有效地控制电网中的潮流,在相位和幅值可控交交变换器(AC-AC converter with controllable phase and amplitude,ACCPA)的基础上结合统一潮流控制器(Unified power flow controller,UPFC)和电压矢量合成技术,提出了一种电压合成型直... 详细信息

为有效地控制电网中的潮流,在相位和幅值可控交交变换器(AC-AC converter with controllable phase and amplitude,ACCPA)的基础上结合统一潮流控制器(Unified power flow controller,UPFC)和电压矢量合成技术,提出了一种电压合成型直接潮流控制器(Synthetic voltage direct power flow controller,SVDPFC)。该控制器由6个Buck交流变换单元、两个输入变压器、一个输出变压器以及两个选择开关组成,可以用来同时调节电网节点电压的幅值和相位,从而来调节电网中的有功潮流和无功潮流。SVDPFC的输出电压相对于输入电压,相位可在90°范围内调节,在两个选择开关的共同作用下其调节范围可以拓展到360°,本文详细阐述了SVDPFC的基本拓扑结构和工作方法并用仿真对其理论分析进行了验证。

关键词：电力潮流 UPFC 相位调节输电线路

A decline in snow cover area of Passu and Ghulkin valleys between 1995 and 2022

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Journal of Mountain Science 2023年第12期20卷 3542-3551页

作者： Imran HUSSAIN Mumtaz ali Sher MUHAMMAD wajid HASSAN Salar ali Zakir HUSSAIN Syed Hammad ali Shaukat ali Muhammad Younis khan Department of Environmental Sciences University of BaltistanSkardu 16100Pakistan Micromaps IT and GIS Consultancy LLC 26135UAE International Centers for Integrated Mountain Development(ICIMOD) G.P.O.Box 3226KathmanduNepal Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Glacier Monitoring Research Centre(GMRC) Water and Power Development Authority(WAPDA)Lahore 54000Pakistan SickKids Centre for Global Child Health The Hospital for Sick ChildrenTorontoOntario M5G 2L3Canada Global Change Impact Studies Center(GCISC) Islamabad 44000Pakistan Departments of Earth Sciences College of ScienceSultan Qaboos UniversityMuscat 123Oman National Centers of Excellence in Geology(NCEG) University of PeshawarPeshawar 25130Pakistan

The global cryosphere is experiencing accelerated melting due to climate change.Currently,the Karakoram anomaly is under discussion with a debate about the possibility that the anomaly may have recently ended.This study aims to evaluate the up-to-date changes in snow cover in the western Karakoram region.We observed the snow cover changes in Passu and Ghulkin valleys in the Hunza River basin(HRB)of the Karakoram through multitemporal Landsat satellite data between 1995 and 2022.We found a significant reduction in snow cover in these valleys,with an average reduction rate of 0.42 km~2/yr,resulting in a total reduction of~11.46 km~2 between 1995 and 2022.This reduction in snow cover is consistent with the mass loss of glaciers in the Karakoram region in recent years.The decline in snow cover in these valleys is also consistent with the meteorological data.The temperature in summer(June)has significantly increased whereas the precipitation in the accumulation season(March)has decreased.These rapid changes suggest that it is crucially important to monitor the snow cover on a regular basis to support downstream management of snowmelt runoff.In addition,there is a need of planning for mitigation and adaptation strategies for snow-related hazards.

关键词： Cryosphere Snow covers area Climate change Karakoram

Polarization-selective nanogold absorber by twisted stacking

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Nano Research 2023年第7期16卷 10392-10400页

作者： Fei Wang Zexiang Han Juehan Sun wajid ali Xiaoli Wang Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Metamaterial absorbers show great promise for applications in optical manipulation,photodetection,solar energy harvesting,and photocatalysis.In this work,we present a twisted stacked metamaterial design that serves as a plasmonic perfect absorber with polarization selectivity.Leveraging effective energy localization,the metamaterial realizes a near-unity absorbance of up to 99.6%for right circularly polarized incidence and 97.2%for left circularly polarized incidence.At a longer wavelength in the visible range,the chiral metamaterial becomes more sensitive to the polarization state of the incident wave,retaining an ultrahigh absorption of light(~94%)for only a given polarization state,that is,light in this polarization state is effectively shielded.A giant circular dichroism signal of up to 7°can be simultaneously observed.Electromagnetic field and charge distribution simulations further reveal that the ultrahigh performance of the design is attributed to the interplay between cavity coupling,magnetic resonances,and plasmonic coupling.Besides switchable and tunable chirality,the plasmonic metamaterial presents a nearperfect absorption band with tunable operational wavelengths.We envision that the high-performance chiral gold metamaterial proposed here can serve as a good candidate for light trapping,chirality sensing,polarized light detection,and polarizationenhanced photocatalysis.

关键词： perfect absorber chirality plasmonic metal-dielectric-metal magnetic field enhancement

Optoelectronic and elastic properties of metal halides double perovskites Cs_(2)InBiX_(6)(X = F, Cl, Br, I)

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Chinese Optics Letters 2021年第3期19卷 17-26页

作者： Muhammad Saeed Izaz Ul Haq Shafiq Ur Rehman Akbar ali wajid ali Shah Zahid ali Qasim khan Imad khan State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China College of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China Center for Computational Materials Science Department of PhysicsUniversity of MalakandChakdaraPakistan College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China College of Electronic Science and Technology Shenzhen UniversityShenzhen 518000China

Structural geometry, electronic band gaps, density of states, optical and mechanical properties of double perovskite halides Cs2InBiX6(X = F, Cl, Br, I) are investigated using the density functional theory. These compounds possess genuine perovskite stoichiometry, evaluated using various geometry-based indices like tolerance factor, octahedral factor, and formation energy. The fundamental electronic band gaps are direct and valued in the range 0.80–2.79 e V. These compounds have narrow band gaps(except Cs2InBiX6) due to strong orbital coupling of the cations. The valence band maximum and conduction band minimum are confirmed to be essentially of In 5 s and Bi 6 p characters, respectively. The splitting of Bi 6 p bands due to strong spin-orbit coupling causes reduction in the band gaps. These compounds have large dispersion in their bands and very low carrier effective masses. The substitution of halogen atoms has great influence on the optical properties. The mechanical properties reveal that Cs2InBiX6(X = F, Cl, Br, I) satisfy the stability criteria in cubic structures.

关键词： optical materials metal halides density functional theory perovskite stoichiometry spin-orbit coupling

COVIDX: Computer-aided diagnosis of COVID-19 and its severity prediction with raw digital chest X-ray scans

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Quantitative Biology 2022年第2期10卷 208-220页

作者： wajid Arshad Abbasi Syed ali Abbas Saiqa Andleeb Maryum Bibi Fiaz Majeed Abdul Jaleel Muhammad Naveed Akhtar Computational Biology and Data Analysis Lab Department of Computer Sciences&Information TechnologyKing Abdullah CampusUniversity of Azad Jammu&KashmirMuzaffarabadAJ&K 13100Pakistan Biotechnology Lab Department of ZoologyKing Abdullah CampusUniversity of Azad Jammu&KashmirMuzaffarabadAJ&K 13100Pakistan Department of Software Engineering University of GujratGujrat 50700Pakistan Department of Computer Science (RCET)UETLahore 54000Pakistan Computational and Internet Services Division Pakistan Institute of Engineering and Applied Sciences(PIEAS)Islamabad 44000Pakistan

Background: Coronavirus disease (COVID-19) is a contagious infection caused by severe acute respiratory syndrome coronavirus-2 (SARS-COV-2) and it has infected and killed millions of people across the globe.Objective: In the absence or inadequate provision of therapeutic treatments of COVID-19 and the limited convenience of diagnostic techniques, there is a necessity for some alternate spontaneous screening systems that can easily be used by the physicians to rapidly recognize and isolate the infected patients to circumvent onward surge. A chest X-ray (CXR) image can effortlessly be used as a substitute modality to diagnose the COVID-19.Method: In this study, we present an automatic COVID-19 diagnostic and severity prediction system (COVIDX) that uses deep feature maps of CXR images along with classical machine learning algorithms to identify COVID-19 and forecast its severity. The proposed system uses a three-phase classification approach (healthy vs unhealthy, COVID-19 vs pneumonia, and COVID-19 severity) using different conventional supervised classification algorithms.Results: We evaluated COVIDX through 10-fold cross-validation, by using an external validation dataset, and also in a real setting by involving an experienced radiologist. In all the adopted evaluation settings, COVIDX showed strong generalization power and outperforms all the prevailing state-of-the-art methods designed for this purpose.Conclusions: Our proposed method (COVIDX), with vivid performance in COVID-19 diagnosis and its severity prediction, can be used as an aiding tool for clinical physicians and radiologists in the diagnosis and follow-up studies of COVID-19 infected patients.Availability: We made COVIDX easily accessible through a cloud-based webserver and python code available at https://***/view/wajidarshad/software and https://***/wajidarshad/covidx, respectively.

关键词： coronavirus COVID-19 radiology machine learning chest X-ray contagious infection

Characterization of lipid parameters in diabetic and non-diabetic atherosclerotic patients

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Journal of Geriatric Cardiology 2015年第1期12卷 37-43页

作者： Fatima ali Hassan Jamil Sanam Saiqa Anwar Nadia wajid Institute of Molecular Biology and Biotechnology (IMBB) & Centre for Research in Molecular Medicine (CRIMM) University of Lahore 1-Kin Defence Road Lahore Pakistan

背景 &；在类脂化合物侧面不安和糖尿病之间的 ObjectiveThe 关系联系了复杂并发症长是兴趣的一个区域。Dyslipidemia 在糖尿病的病人是心血管的病态和死亡的一个有势力预言者。现在的学习的目的是在百和 76 个个人(45-75 年年... 详细信息

背景 &；在类脂化合物侧面不安和糖尿病之间的 ObjectiveThe 关系联系了复杂并发症长是兴趣的一个区域。Dyslipidemia 在糖尿病的病人是心血管的病态和死亡的一个有势力预言者。现在的学习的目的是在百和 76 个个人(45-75 年年龄) 参予了的糖尿病、非糖尿病的动脉粥样硬化患者 patients.MethodsFive 调查在老化和类脂化合物侧面之间的关系这研究。在这些之中， 192 正在有糖尿病 mellitus 和动脉粥样硬化的历史。个人们在健康的底上被分类(正常、非糖尿病的动脉粥样硬化，糖尿病的动脉粥样硬化) 并且年龄(45-55 年， 56-65 年，和 66-75 年) 。所有参加者受到象详细历史一样的过程，为 fasting 血糖的生物化学的分析，血红素 A1c，全部的胆固醇(TC ) ， triglycerides (TG ) ，低密度的脂蛋白 --(LDL ) ，很低密度的脂蛋白(VLDL ) 和高密度的脂蛋白(HDL ) 。所有这些参数在所有三个年龄组的糖尿病、非糖尿病的动脉粥样硬化患者病人之间被比较。TC/HDL 和 LDL/HDL 也是有的 calculated.ResultsDiabetic 动脉粥样硬化患者个人(男性和女性) 与非糖尿病的动脉粥样硬化患者和正常控制个人相比的 HDL 的 TC， TG， LDL， VLDL 和底层高级。在所有三个年龄组之中，脂蛋白反常被观察比男性在女性更经常。在与年龄相比的糖尿病的动脉粥样硬化患者题目 TC/HDL 和 LDL/HDL 比率有重要增加，性别随两性的年龄的增加匹配非糖尿病的动脉粥样硬化患者和 dyslipidemia 增加的正常 control.ConclusionsDegree。女性是对糖尿病的 dyslipidemia 敏感的更多并且因此有与增加年龄开发动脉粥样硬化的更多的风险。

关键词：动脉粥样硬化糖尿病患者极低密度脂蛋白 VLDL 血脂异常表征脂质

Power Aggregation Operators and Similarity Measures Based on Improved Intuitionistic Hesitant Fuzzy Sets and their Applications to Multiple Attribute Decision Making

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Computer Modeling in Engineering & Sciences 2021年第3期126卷 1165-1187页

作者： Tahir Mahmood wajid ali Zeeshan ali Ronnason Chinram Department of Mathematics and Statistics International Islamic UniversityIslamabadPakistan Algebra and Applications Research Unit Division of Computational ScienceFaculty of SciencePrince of Songkla UniversityHat YaiSongkhlaThailand

Intuitionistic hesitant fuzzy set(IHFS)is amixture of two separated notions called intuitionistic fuzzy set(IFS)and hesitant fuzzy set(HFS),as an important technique to cope with uncertain and awkward information in realistic decision issues.IHFS contains the grades of truth and falsity in the formof the subset of the unit interval.The notion of IHFS was defined by many scholars with different conditions,which contain several weaknesses.Here,keeping in view the problems of already defined IHFSs,we will define IHFS in another way so that it becomes compatible with other existing notions.To examine the interrelationship between any numbers of IHFSs,we combined the notions of power averaging(PA)operators and power geometric(PG)operators with IHFSs to present the idea of intuitionistic hesitant fuzzy PA(IHFPA)operators,intuitionistic hesitant fuzzy PG(IHFPG)operators,intuitionistic hesitant fuzzy power weighted average(IHFPWA)operators,intuitionistic hesitant fuzzy power ordered weighted average(IHFPOWA)operators,intuitionistic hesitant fuzzy power ordered weighted geometric(IHFPOWG)operators,intuitionistic hesitant fuzzy power hybrid average(IHFPHA)operators,intuitionistic hesitant fuzzy power hybrid geometric(IHFPHG)operators and examined as well their fundamental properties.Some special cases of the explored work are also discovered.Additionally,the similarity measures based on IHFSs are presented and their advantages are discussed along examples.Furthermore,we initiated a new approach to multiple attribute decision making(MADM)problem applying suggested operators and a mathematical model is solved to develop an approach and to establish its common sense and adequacy.Advantages,comparative analysis,and graphical representation of the presented work are elaborated to show the reliability and effectiveness of the presented works.

关键词： Intuitionistic fuzzy sets intuitionistic hesitant fuzzy sets power aggregation operators similarity measures multiple attribute decision making