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Progress in Natural Science:Materials International 2015年第6期25卷 622-630页

作者： qamar abbas Fran?ois Béguin Institute of Chemistry and Technical Electrochemistry Poznan University of Technology

Self-discharge(SD) of AC/AC(AC ? activated carbon) electrochemical capacitors in aqueous solutions of lithium sulfate(Li2SO4) and lithium sulfate t iodide salts(Li2SO4tKI or Li2SO4tLi I) was investigated at 24 1C and 40 1C after cell potential hold at values from 1 V to 1.6 V.At24 1C,the cells exhibit lower SD in Li2SO4tKI than in Li2SO4,owing to the redox activity of the 2I /I2 system which drives the positive AC electrode to operate in narrow potential range and display lower potential drop than in Li2SO4.At 401 C,the capacitors exhibit comparable and reduced SD both in Li2SO4tLi I and Li2SO4,whatever the holding cell potential.Three-electrode cell experiments demonstrate that,at 40 1C,hydrogen chemisorption is thermodynamically unfavored under negative polarization,while the activity of the 2I /I2 redox system under positive polarization is only slightly reduced.As a consequence,the AC/AC cells in Li2SO4 exhibit a typical electrical double-layer performance at 401 C,whereas they still behave as hybrid ones in Li2SO4tLi I,with twice higher capacitance than in Li2SO4.The(Ui-Ut) vs t1/2plots demonstrate that SD is essentially controlled by diffusion at 401 C,suggesting that it originates from bulkier hydrated ions.Overall,in the investigated temperature range,the AC/AC capacitors in Li2SO4tLi I demonstrate low self-discharge and high capacitance,while being able to operate up to 1.6 V.

关键词： Supercapacitors Activated carbon Self-discharge Salt aqueous electrolyte Iodide/iodine redox system Activation and diffusion controlled mechanisms

Convergence Track Based Adaptive Differential Evolution Algorithm(CTbADE)

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Computers, Materials & Continua 2022年第7期72卷 1229-1250页

作者： qamar abbas Khalid Mahmood Malik Abdul Khader Jilani Saudagar Muhammad Badruddin Khan Mozaherul Hoque Abul Hasanat Abdullah AlTameem Mohammed AlKhathami Department of Computer Science and Software Engineering International Islamic UniversityIslamabad44000Pakistan Department of Computer Science and Engineering Oakland UniversityRochesterMIUSA Information Systems Department College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)RiyadhSaudi Arabia

One of the challenging problems with evolutionary computing algorithms is to maintain the balance between exploration and exploitation capability in order to search global optima.A novel convergence track based adaptive differential evolution(CTbADE)algorithm is presented in this research paper.The crossover rate and mutation probability parameters in a differential evolution algorithm have a significant role in searching global optima.A more diverse population improves the global searching capability and helps to escape from the local optima problem.Tracking the convergence path over time helps enhance the searching speed of a differential evolution algorithm for varying problems.An adaptive powerful parameter-controlled sequences utilized learning period-based memory and following convergence track over time are introduced in this paper.The proposed algorithm will be helpful in maintaining the equilibrium between an algorithm’s exploration and exploitation capability.A comprehensive test suite of standard benchmark problems with different natures,i.e.,unimodal/multimodal and separable/non-separable,was used to test the convergence power of the proposed CTbADE algorithm.Experimental results show the significant performance of the CTbADE algorithm in terms of average fitness,solution quality,and convergence speed when compared with standard differential evolution algorithms and a few other commonly used state-of-the-art algorithms,such as jDE,CoDE,and EPSDE algorithms.This algorithm will prove to be a significant addition to the literature in order to solve real time problems and to optimize computationalmodels with a high number of parameters to adjust during the problem-solving process.

关键词： Differential evolution function optimization convergence track parameter sequence adaptive control parameters

Implications of electrode modifications in aqueous organic redox flow batteries

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Journal of Energy Chemistry 2024年第8期95卷 499-510页

作者： Zahid Manzoor Bhat Mohammad Furquan Muhammad Aurang Zeb Gul Sial Umair Alam Atif Saeed Alzahrani Mohammad qamar Interdisciplinary Research Center for Hydrogen Technologies and Carbon Management(IRC-HTCM) King Fahd University of Petroleum & Minerals(KFUPM) Department of Materials Science and Engineering King Fahd University of Petroleum and Minerals Interdisciplinary Research Center for Sustainable Energy Systems(IRC-SES) King Fahd University of Petroleum and Minerals

Aqueous organic redox flow batteries(RFBs) exhibit favorable characteristics, such as tunability, multielectron transfer capability, and stability of the redox active molecules utilized as anolytes and catholytes, making them very viable contenders for large-scale grid storage applications. Considerable attention has been paid on the development of efficient redox-active molecules and their performance optimization through chemical substitutions at various places on the backbone as part of the pursuit for high-performance RFBs. Despite the fact that electrodes are vital to optimal performance, they have not garnered significant attention. Limited research has been conducted on the effects of electrode modifications to improve the performance of RFBs. The primary emphasis has been given on the impact of electrode engineering to augment the efficiency of aqueous organic RFBs. An overview of electron transfer at the electrode–electrolyte interface is provided. The implications of electrode modification on the performance of redox flow batteries, with a particular focus on the anodic and cathodic half-cells separately, are then discussed. In each section, significant discrepancies surrounding the effects of electrode engineering are thoroughly examined and discussed. Finally, we have presented a comprehensive assessment along with our perspectives on the future trajectory.

关键词： Electrode modification Organic redox molecules Outer sphere and inner sphere Redox flow batteries

A Novel Approach to Energy Optimization:Efficient Path Selection in Wireless Sensor Networks with Hybrid ANN

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Computers, Materials & Continua 2024年第5期79卷 2945-2970页

作者： Muhammad Salman qamar Ihsan ulHaq Amil Daraz Atif MAlamri Salman A.AlQahtani Muhammad Fahad Munir Department of Electrical and Computer Engineering International Islamic UniversityIslamabad44000Pakistan School of Information Science and Engineering NingboTech UniversityNingbo315100China Software Engineering Department College of Computer and Information SciencesKing Saud UniversityRiyadh11495Saudi Arabia Computer Engineering Department College of Computer and Information SciencesKing Saud UniversityRiyadh11495Saudi Arabia

In pursuit of enhancing the Wireless Sensor Networks(WSNs)energy efficiency and operational lifespan,this paper delves into the domain of energy-efficient routing protocols.InWSNs,the limited energy resources of Sensor Nodes(SNs)are a big challenge for ensuring their efficient and reliable operation.WSN data gathering involves the utilization of a mobile sink(MS)to mitigate the energy consumption problem through periodic network traversal.The mobile sink(MS)strategy minimizes energy consumption and latency by visiting the fewest nodes or predetermined locations called rendezvous points(RPs)instead of all cluster heads(CHs).CHs subsequently transmit packets to neighboring RPs.The unique determination of this study is the shortest path to reach RPs.As the mobile sink(MS)concept has emerged as a promising solution to the energy consumption problem in WSNs,caused by multi-hop data collection with static sinks.In this study,we proposed two novel hybrid algorithms,namely“ Reduced k-means based on Artificial Neural Network”(RkM-ANN)and“Delay Bound Reduced kmeans with ANN”(DBRkM-ANN)for designing a fast,efficient,and most proficient MS path depending upon rendezvous points(RPs).The first algorithm optimizes the MS’s latency,while the second considers the designing of delay-bound paths,also defined as the number of paths with delay over bound for the MS.Both methods use a weight function and k-means clustering to choose RPs in a way that maximizes efficiency and guarantees network-wide coverage.In addition,a method of using MS scheduling for efficient data collection is provided.Extensive simulations and comparisons to several existing algorithms have shown the effectiveness of the suggested methodologies over a wide range of performance indicators.

关键词： Wireless Sensor Networks(WSNs) mobile sink(MS) rendezvous point(RP) machine learning Artificial Neural Networks(ANNs)

Carbon/carbon supercapacitors

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Journal of Energy Chemistry 2013年第2期22卷 226-240页

作者： Elzbieta Frackowiak qamar abbas Franois Bguin Institute of Chemistry and Technical Electrochemistry Poznan University of Technology Piotrowo 3 60-965 Poznan Poland

Supercapacitors, or electrochemical capacitors, are a power storage system applied for harvesting energy and delivering pulses during short periods of time. The commercially available technology is based on charging an electrical double-layer （EDL）, and using high surface area carbon electrodes in an organic electrolyte. This review first presents the state-of-the-art on EDL capacitors, with the objective to better understand their operating principles and to improve their performance. In particular, it is shown that capacitance might be enhanced for carbons having subnanometric pores where ions of the electrolyte are distorted and partly desolvated. Then, strategies tbr using environment l^endly aqueous electrolytes are presented. In this case, the capacitance can be enhanced through pseudo-faradaic contributions involving i） surface functional groups on carbons, ii） hydrogen electrosorption, and iii） redox reactions at the electrode/electrolyte interface. The most promising system is based on the use of aqueous alkali sulfate as electrolyte allowing voltages as high as 2 V to be reached, due to the high overpotential for di-hydrogen evolution at the negative electrode.

关键词： supercapacitors electrochemical capacitors porous carbons electrolytes pore size pseudocapacitance

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Dinitrophenyl-oxadiazole compounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang Cong Li Mou Sun qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu Jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group CO. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military composite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast explosives.In this work,a series of dinitrophenyl-oxadiazole compounds were designed and prepared.These compounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these compounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectroscopy,elemental analysis.Compounds 2,3 were unambiguously confirmed by X-ray single crystal diffraction analysis.As a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

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Petrology and Petrographic Delineation of Kamlial Formation Sandstone Mong and Thorar Village, Northern Pakistan

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Journal of Geoscience and Environment Protection 2024年第5期12卷 302-324页

作者： Ehtisham Mehmood Haishen Lv Pei Gao Soban qamar The National Key Laboratory of Water Disaster Prevention College of Hydrology and Water Resources Hohai University Nanjing China College of Mechanical and Petroleum Engineering University of Engineering and Technology Taxila Pakistan

The origin of sandstone in the Rawalpindi group is disputed because of the lesser Himalayas complicated geological structure and ongoing tectonic activity. The goal of the study is to learn more about the petrographic and geological aspects of the Siwalik molasses deposits, which are formations that belong to the same age group. The Early Miocene Kamlial Formation, the Middle to Late Miocene Chinji Formation, and the Late Miocene Nagri Formation are the stratigraphic units revealed in the project area. The texture of the sandstone found in the Rawalpindi Group and Siwalik is fine to medium-grained. The hue ranges from grey to greenish grey. The sandstone displays thin to medium-bedded layers and exhibits thin lamination throughout. The sandstone of the Kamlial Formation contains load casts, potholes, worm burrows, hematite layers, and filled and unfilled mud cracks in basic structures. Model petrographic research reveals that the Murree Formation primarily consists of light minerals like feldspar, quartzite, and felice, whereas the Kamlial Formation is composed of heavy minerals like garnet and tourmaline. Sandstone from the Rawalpindi group undergoes analysis to ascertain its provenance using the quartz feldspar lithic fragments ternary diagram technique. Each plot in the QFL diagram’s recycled orogeny provenance field is plotted.

关键词： Hazara Kashmir Syntaxis Rawalpindi Group Siwalik Group Himalayas Neogene

In vitro,in vivo and in silico anti-hyperglycemic inhibition by sinigrin

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Asian Pacific Journal of Tropical Medicine 2017年第4期10卷 352-358页

作者： qamar abbas Mubashir Hassan Hussain Raza Song Ja Kim Ki-Wha Chung Gwang-Hoon Kim Sung-Yum Seo Department of Biological Sciences College of Natural SciencesKongju National University56 Gongjudehak-Ro 56GongjuChungnam 32588Republic of Korea

Objective:To evaluate the anti-hyperglycemic potential of sinigrin using in ritro.in silico and in riro streptozotocin(STZ) induced hyperglycemic zebrafish model.Methods:The in vitro enzyme inhibition assay was carried out to determine the IC_(50) value against α-glucosidase and α-amylase.in silico molecular docking was performed against both enzymes with PyRx tool and simulations were performed using GROMACS tool.Hyperglycemia was induced in zebrafishes using three intraperitoneal injections on alternating days for one week at 350mg/kg of STZ.Hyperglycemic fishes were treated intraperitoncally with 50.100 and 150 mg of sinigrin/kg of body weight for 24 h and glucose levels were measured.Results:The sinigrin showed very strong inhibition against α-glucosidase and α-amylase with 0.248 and0.00124 μM while reference drug acarbose showed IC_(50) value of 73.0700 and 0.0017 μM against α-glucosidase and α-amylase,respectively.Kinetic analysis revealed that sinigrin has the mixed type mode of inhibition against α-glucosidase.Molecular docking results revealed its strong binding affinity with α-glucosidase(-10.00 Kcal/mol) and α-amylase(-8.10 Kcal/mol).Simulations graphs confirmed its stability against both enzymes.Furthermore.in hyperglycemic zebrafishes most significant(P<0.001) reduction of glucose was occurred at150 mg/kg.moderate significant reduction of glucose was observed at 100 mg/kg and no any significant reduction of glucose was measured at 50 mg/kg.Conclusions:It can be evident from the present results that sinigrin has potent anti-hyperglycemic activity and it may prove to be effective treatment for the hyperglycemia.

关键词： Anti-hyperglycemia MD simulations Sinigrin Zebrafish α-amylase α-glucosidase

ABMRF:An Ensemble Model for Author Profiling Based on Stylistic Features Using Roman Urdu

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Intelligent Automation & Soft Computing 2024年第2期39卷 301-317页

作者： Aiman Muhammad Arshad Bilal Khan Khalil Khan Ali Mustafa qamar Rehan Ullah Khan Department of Computer Science City University of Science and Information TechnologyPeshawarPakistan Department of Computer Science School of Engineering and Digital SciencesNazarbayev UniversityAstanaKazakhstan Department of Computer Science College of ComputerQassim UniversityBuraydahSaudi Arabia Department of Information Technology College of ComputerQassim UniversityBuraydahSaudi Arabia

This study explores the area of Author Profiling(AP)and its importance in several industries,including forensics,security,marketing,and education.A key component of AP is the extraction of useful information from text,with an emphasis on the writers’ages and genders.To improve the accuracy of AP tasks,the study develops an ensemble model dubbed ABMRF that combines AdaBoostM1(ABM1)and Random Forest(RF).The work uses an extensive technique that involves textmessage dataset pretreatment,model training,and assessment.To evaluate the effectiveness of several machine learning(ML)algorithms in classifying age and gender,including Composite Hypercube on Random Projection(CHIRP),Decision Trees(J48),Na飗e Bayes(NB),K Nearest Neighbor,AdaboostM1,NB-Updatable,RF,andABMRF,they are compared.The findings demonstrate thatABMRFregularly beats the competition,with a gender classification accuracy of 71.14%and an age classification accuracy of 54.29%,respectively.Additional metrics like precision,recall,F-measure,Matthews Correlation Coefficient(MCC),and accuracy support ABMRF’s outstanding performance in age and gender profiling tasks.This study demonstrates the usefulness of ABMRF as an ensemble model for author profiling and highlights its possible uses in marketing,law enforcement,and education.The results emphasize the effectiveness of ensemble approaches in enhancing author profiling task accuracy,particularly when it comes to age and gender identification.

关键词： Machine learning author profiling AdaBoostM1 random forest ensemble learning text classification

Testing Procedure for Laboratory Scale Semi Cryogenic Combustion Chamber of LPRE with Problems Faced and Lessons Learned

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Journal of Thermal Science 2022年第6期31卷 2171-2177页

作者： KHAN Taj Wali qamar Ihtzaz Department of Aeronautics and Astronautics Institute of Space TechnologyIslamabad 44000Pakistan

Design, development, and testing of LPRE(Liquid Propellant Rocket Engine) are difficult and expensive tasks. Prior to full-scale design, it is indispensable to optimize important parameters at sub-scale. Propellants flow rates are low for a sub-scale or laboratory scale combustion chambers. It is hard to satisfy chamber cooling and chill feed lines quickly with low flow rates of propellants. This paper proposes a detailed procedure for testing of a laboratory scale semi-cryogenic combustion chamber. Many tests were conducted with a small scale adjustable length combustion chamber. The injection head of the chamber was interchangeable. Liquid-liquid pressure swirl injector and like impinging injectors were used with two different injection heads. Liquid oxygen and kerosene were used as oxidizer and fuel, respectively. Oxidizer to fuel mixing ratio was 0.29-0.45 and the total propellant mass flow rate was 0.06-0.1 kg/s. Problems were faced during testing, including, explosion in the combustion chamber, fuel injector blockage, unstable combustion, incomplete chilling and blockage of cooling water channel, etc. A detailed procedure is designed on the basis of the lessons learned which was experimentally proved.

关键词： LPRE cryogenic testing procedure combustion chamber

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