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An Improved Perturb and Observe Maximum Power Point Tracking Algorithm for Photovoltaic Power Systems

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1165-1175页

作者： Rasool Kahani Mohsin jamil M.Tariq Iqbal Department of Electrical and Computer Engineering Memorial University of NewfoundlandSt.John’sA1B 3X5Canada

This paper aims to improve the performance of the conventional perturb and observe(P&O)maximum power point tracking(MPPT)*** the oscillation around the maximum power point(MPP)is the main disadvantage of this technique,we introduce a modified P&O algorithm to conquer this *** new algorithm recognizes approaching the peak of the photovoltaic(PV)array power curve and prevents the oscillation around the *** key to achieve this goal is testing the change of output power in each cycle and comparing it with the change in array terminal power of the previous *** a decrease in array terminal power is observed after an increase in the previous cycle or in the opposite direction,an increase in array terminal power is observed after a decrease in the previous cycle;it means we are at the peak of the power curve,so the duty cycle of the boost converter should remain the same as the previous ***,an optimized duty cycle is introduced,which is adjusted based on the operating point of PV ***,a DC-DC boost converter powered by a PV array simulator is used to test the proposed *** the irradiance changes,the proposed algorithm produces an averageηMPPT of nearly 3.1%greater than that of the conventional P&O algorithm and the incremental conductance(In C)*** addition,under strong partial shading conditions and drift avoidance tests,the proposed algorithm produces an averageηMPPT of nearly 9%and 8%greater than that of the conventional algorithms,respectively.

关键词： Photovoltaic system maximum power point tracking(MPPT) perturb and observe(P&O) boost converter steady-state performance

Blend of Polyhydroxyalkanoates Synthesized By Lipase Positive Bacteria From Plant Oils

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Journal of Renewable Materials 2019年第5期7卷 463-476页

作者： Nasir Javaid Rida Batool Nazia jamil Department of Microbiology and Molecular Genetics University of the PunjabQuaid-e-Azam CampusLahore-54590Pakistan

A total of 5 biochemically characterized lipase positive bacterial strains were screened for Polyhydroxyalkanoates(PHA)production by Nile blue staining and confirmation was done by Sudan Black *** production ability for all strains was optimized followed by time profiling calculation and comparison via using glucose and two plant oils i.e.,canola and mustard *** analysis showed that glucose can serve as a carbon source for maximum biomass(2.5 g/L CDW for strain 5)and PHA production(70.3%for strain 2).PHA produced by strain 2 was further analyzed for its chemical composition and type via Fourier Transform Infrared(FT-IR)*** revealed homopolymer(PHB)and copolymer(PHB-co-PHV)production of PHA(peaks at 1743 cm-1 and 2861 cm-1,respectively)with both canola and mustard oil unlike glucose which produced only homopolymer one i.e.,PHB(peaks at 1110 cm-1,1411 cm-1 and 1650 cm-1).Crystallinity of FT-IR analyzed PHA was calculated using mathematical formulas which showed decrease from glucose to canola to mustard *** study revealed that plant oils can serve as better carbon source to produce better quality(ductile and copolymer)***,16S rRNA gene sequencing analysis showed that strain 1,strain 2,strain 3,strain 4 and strain 5 are Stenotrophomonas sp.N3,Exiguobacterium sp.N4,Exiguobacterium ***3,Cellulosimicrobium sp.A8 and Klebsiella ***2,respectively.

关键词： Bioplastics polyhydroxyalkanoates lipase positive bacteria plant oils,FT-IR

Gyroscope precession frequency analysis of a five-dimensional charged rotating Kaluza-Klein black hole

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Chinese Physics C 2020年第6期44卷 143-153页

作者： Mustapha Azreg-Aïnou Mubasher jamil Kai Lin Engineering Faculty Başkent UniversityBağlıca CampusAnkaraTurkey Institute for Theoretical Physics and Cosmology Zhejiang University of TechnologyHangzhou 310023China School of Natural Sciences National University of Sciences and TechnologyH-12Islamabad 44000Pakistan Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

We study the spin precession frequency of a test gyroscope attached to a stationary observer in the five-dimensional rotating Kaluza-Klein black hole(RKKBH). We derive the conditions under which the test gyroscope moves along a timelike trajectory in this geometry, and the regions where the spin precession frequency diverges. The magnitude of the gyroscope precession frequency around the KK black hole diverges at two spatial locations outside the event horizon. However, in the static case, the behavior of the Lense-Thirring frequency of a gyroscope around the KK black hole is similar to the ordinary Schwarzschild black hole. Since a rotating Kaluza-Klein black hole is a generalization of the Kerr-Newman black hole, we present two mass-independent schemes to distinguish these two spacetimes.

关键词： rotating black hole Kaluza-Klein spin precession gyroscope

Kinetics of the exchange reaction catalyzed by 2-amino-3- ketobutyrate CoA ligase

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Frontiers in Biology 2015年第6期10卷 503-507页

作者： Farrukh jamil School of Biological Sciences University of the Punjab New Campus Lahore 54590 Punjab Pakistan Department of Biosciences COMSATS Institute of Information Technology(CIIT) Sahiwal 57000 Punjab Pakistan

2-Amino-3-ketobutyrate CoA ligase （KBL） of Escherichia coli is a member of the a-oxoamine synthase family; it catalyzes the condensation reaction between glycine and acetyl CoA to yield 2-amino-3-ketobutyrate. We have previously shown that KBL catalyzes the exchange ofpro-R hydrogen of glycine with protons in the medium; however, the kinetics of this reaction has never been determined. In this study, we calculated the kinetic parameters of this exchange reaction by using different concentrations of [2RS- 3H2： 2-14C] glycine. The rate of the exchange reaction was determined by measuring the 3H/14C ratio in recovered ｜2S- 3H： 2J4C]glycine. The Lineweaver-Burk plot showed that Km and kcat of this reaction were 3.8 ×10^-3 M and 0.22 S^-11, respectively. On the other hand, Km and kcat values of the overall KBL-mediated catalysis were correspondingly 1.23 × 10^-2 M and 1.19 S^-1. Thus, the rate of the exchange reaction was almost five times lower than that of overall KBL catalysis.

关键词： enzyme 2-amino-3-ketobutyrate CoA ligase kinetics exchange reaction

Violation of the First Law of Thermodynamics in f(R,T)Gravity

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Chinese Physics Letters 2012年第10期29卷 265-267页

作者： Mubasher jamil D.Momeni Ratbay Myrzakulov Center for Advanced Mathematics and Physics(CAMP) National University of Sciences and Technology(NUST)H-12IslamabadPakistan Eurasian International Center for Theoretical Physics Eurasian National UniversityAstana 010008Kazakhstan

We derive the first law of thermodynamics using the method proposed by *** the entropy as Noether charge and comparing with the usual first law of thermodynamics,we obtain explicitly the expression of entropy which contains infinitely many non-local terms(*** integral terms).We have proved,in general,that the first law of black hole thermodynamics is violated for f(R,T)***,there might exist some special cases in which the first law for f(R,T)gravity is recovered.

关键词： thermodynamics entropy infinitely

Predictors of complicated dengue infections in endemic region of Pakistan

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Asian Pacific Journal of Tropical Medicine 2022年第11期15卷 496-502页

作者： Ikram Waheed Samreen Khalid Zubia jamil Department of Medicine Fauji Foundation HospitalRawalpindi 46000Pakistan Department of Medicine Foundation University Medical CollegeFoundation UniversityDHA Phase 1 Islamabad 44000Pakistan

Objective:To predict the factors associated with progression to severe dengue infection to prevent potentially fatal complications and to identify the determinants of severe complicated ***:The study was conducted in a tertiary care hospitaldengue ward from September to November 2021 including confirmed dengue infected patients(positive NS1 antigen or antidengue-antibodies IgM).Secondary dengue infection was labelled by positive anti-dengue-antibodies IgG in active dengue infected *** history,physical examination,laboratory and radiological parameters,hospital stay(days)and mortality percentages were *** were classified into three groups according to disease severity:dengue fever(DF),dengue hemorrhagic fever(DHF)and dengue shock syndrome(DSS).The predictors of complicated dengue infection were determined by regression ***:The most common symptom was fever(96.9%).Among 129 patients,62.8%had DF,31.0%had DHF and only 6.2%developed *** of previous symptomatic dengue and positive anti-dengue-antibodies IgG were present in 100%DSS patients and nearly 75.0%DHF patients(P<0.05).The moratlity rate in patients with DSS,DHF and DF was 50.0%,2.5%and none respectively(P<0.05).Clinical parameters(body aches,bleeding,conjunctival hemorrhage,maculopapular rash,right hypochondrial tenderness,ascites,pleural effusion)and laboratory parameters(thrombocytopenia,raised alanine aminotransferase and secondary dengue infection)were determinants that complicate the dengue ***:Thrombocytopenia,raised alanine aminotransferase and secondary dengue infection are important laboratory parameters to complicate the disease process of dengue infection.

关键词： Dengue fever Severe dengue Endemic diseases Thrombocytopenia Hemorrhage Shock

Effect of deposition parameters on structural and mechanical properties of niobium nitride synthesized by plasma focus device

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Chinese Physics B 2015年第6期24卷 416-424页

作者： jamil Siddiqui Tousif Hussain Riaz Ahmad Nida Khalid Center for Advanced Studies in Physics(CASP) 1-Church RoadGC University Department of Physics Government College University

Effects of deposition angle and axial distance on the structural and mechanical properties of niobium nitride syn- thesized by a dense plasma focus （DPF） system are studied. The x-ray diffraction （XRD） confirms that the deposition parameters affect the growth of multi-phase niobium nitride. Scanning electron microscopy （SEM） shows the granular surface morphology with strong thermally assisted coagulation effects observed at the 5-cm axial distance. The non-porous granular morphology observed at the 9-cm distance along the anode axis is different from those observed at deposition angles of 10° and 20°. Energy dispersive x-ray （EDX） spectroscopy reveals the maximum nitrogen content at the shortest （5 cm） axial position. Atomic force microscopy （AFM） exhibits that the roughness of coated films varies for coatings synthesized at different axial and angular positions, and the Vickers micro-hardness test shows that a maximum hardness value is （08.44 ±0.01） GPa for niobium nitride synthesized at 5-cm axial distance, which is about 500% more than that of a virgin sample.

关键词： DPF device niobium nitride XRD SEM AFM micro-hardness

EMMS mixture model with size distribution for two-fluid simulation of riser flows

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Particuology 2018年第3期16卷 165-173页

作者： Atta Ullah Iqra jamil Adnan Hamid Kun Hong Department of Chemical Engineering Pakistan Institute of Engineering and Applied Sciences Istamabad 45650 Pakistan Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration Jiangsu Provincial Engineering Laboratory for Advanced Materials of Salt Chemical Industry Huaiyin Institute of Technology Huaian 223003 China

Further development of an energy-minimization multiscale modeling approach to simulating two-phase flow under turbulent conditions that considers the size distribution of mesoscale structures, i.e. bubbles and clusters, is presented. User-defined values of minimum and maximum cluster or bubble diame- ters were specified. A uniform size distribution was first considered as a test case, in which the drag force comprised contributions from each size group. The mathematical form of the objective function describing the energy for suspension and transport was not altered. The heterogeneity index of this new drag modification was then used to simulate pilot-scale circulating fluidized-bed risers involving Geldart group A particles. The results were validated against available experimental data. The model is capable of capturing both axial and radial profiles of flow-field variables.

关键词： Mesoscale Bubble Cluster EMMS CFD Riser

Effects of Catalysis and Separator Functionalization on High-Energy Lithium–Sulfur Batteries:A Complete Review

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Energy & Environmental Materials 2023年第3期6卷 333-355页

作者： Muhammad Kashif Aslam Sidra jamil Shahid Hussain Maowen Xu Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University) Ministry of EducationSchool of Materials and EnergySouthwest UniversityChongqing 400715China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China

Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising next-generation rechargeable energy storage ***,the“shuttle effect”of polysulfide results in the passivation of metal lithium anode,the decrease of battery capacity and coulombic efficiency,and the deterioration of cycle *** realize the commercialization of Li-S batteries,its serious“shuttle effect”needs to be *** commercial separators are ineffective to suppress this effect because of its large pore ***,it is an effective strategy to modify the separator surface and introduce functional modified *** addition to the blocking strategy,the catalysis of polysulfide conversion reaction is also an important factor hindering the migration of *** this review,the principles of separator modification,functionalization,and catalysis in Li-S batteries are ***,the research trend of separator functionalization and polysulfide catalysis in the future is prospected.

关键词： catalysis Li-S batteries polysulfides separator functionalization shuttle effect