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Electrostatic Dust Acoustic Solitons in Pair-Ion-Electron Plasmas

Chinese Physics Letters 2012年第6期29卷 207-210页

作者： Hafeez Ur Rehman Theoretical Plasma Physics Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)P.O.NiloreIslamabadPakistan Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences(PIEAS)P.O.NiloreIslamabadPakistan

Using the reductive perturbation method,a Korteweg-de Vries (KdV) equation is derived to study the nonlinear properties of electrostatic collisionless dust acoustic solitons in pair-ion-electron (p-i-e) *** Buid model is chosen for positive ions,negative ions,and the fraction of electrons and charged (both positive and negative)dynamic dust *** is realized that electrostatic hump structures can be found when the dust particles are positively charged,and electrostatic dip structures can be detected for negatively charged dust *** solutions for these dust acoustic solitous are plotted and their characteristics are *** is found that the amplitude and width of the electrostatic dust acoustic solitons increase when the density of the dust particles and/or the temperature of the negative ions increases,and that the amplitude and width of these solitons decrease when the temperature of the positive ions *** pair-ion plasmas mimic electron-positron plasmas,our results might be helpful in understanding the nonlinear dust acoustic solitary waves in super dense astronomical bodies like neutron stars.

关键词： particles electrostatic solitons

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Chemical synthesis of zinc oxide nanorods for enhanced hydrogen gas sensing

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Chinese Physics B 2014年第1期23卷 509-512页

作者： Musarrat Jabeen Muhammad Azhar Iqbal R Vasant Kumar Mansoor Ahmed Muhammad Tayyeb Javed Department of Physics University of the Punjab Lahore Pakistan Department of Material Science and Metallurgy University of Cambridge England Department of Chemical Engineering Pakistan Institute of Engineering and Applied Sciences Nilore Islamabad Pakistan

Zinc oxide （ZnO） nanorods are prepared using equimolar solution of zinc nitrate （（Zn（NO3）2） and hexamethylenete- tramine （C6HleN4） by the hydrothermal technique at 80 ~C for 12 h. Epitaxial growth is explored by X-ray diffraction （XRD） patterns, revealing that the ZnO nanorods have a hexagonal （wurtzite） structure. Absorption spectra of ZnO are measured by UV-visible spectrometer. The surface morphology is investigated by field emission scanning electron mi- croscopy （FESEM）. The synthesized ZnO nanorods are used for detecting the 150 ~C hydrogen gas with a concentration over 1000 ppm. The obtained results show a reversible response. The influence of operating temperature on hydrogen gas detecting characteristic of ZnO nanorods is also investigated.

关键词： zinc oxide hydrothermal synthesis nanorods hydrogen gas sensor

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Laser-driven shock wave dynamics in aluminum target

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Vacuum 2025年 239卷

作者： Ahmad Raza Zia Ur Rehman Sultan Mahmood Saad abdullah Makhdoom Sajjad Tahir Hamza Qayyum Shakir Ullah Physics Division Pakistan Institute of Nuclear Science and Technology Nilore Islamabad 45650 Pakistan Pakistan Institute of Engineering and Applied Sciences Nilore Islamabad 45650 Pakistan Laser-Matter Interaction Laboratory Department of Physics COMSATS University Park Road Islamabad 45550 Pakistan

This study investigates the dynamics of plasma and shock wave generated during nanosecond laser ablation of the aluminum target over a broad range of laser fluence (15-700 J/cm 2 ). The optical probe beam deflection apparatus coupled with laser-induced breakdown spectroscopy is applied to track and elucidate the evolution of laser-induced plasma and shock waves. Our findings reveal a rapid increase in shock wave velocity and pressure with increasing fluence, reaching a maximum of 4 km/s and 100 MPa at 350 J/cm 2 , followed by saturation at higher fluences. These findings align well with the CJ detonation velocity model and Fabbero’s model for laser ablation dynamics. The study also highlights the rapid decay of shock wave’s velocity and pressure in the near-field region, adhering to the Sadowski and blast wave model and approaching typical acoustic waves within a few mm of the target surface. Plasma temperature and electron density peaked at 350 J/cm 2 , confirming the effect of the reflection of the trailing laser pulse by the induced plasma. Our study revealed a direct relationship between SW pressure and ablated mass, resulting in a constant mass-specific shock wave pressure that increases linearly with laser fluence and remains constant beyond 350 J/cm 2 . The laser-induced breakdown spectroscopy analysis also uncovered a significant decrease in the electron number density and plasma temperature with time, following a power-law relationship. These insights enhance understanding of the underlying physics of laser-induced shock wave, paving the way for material processing and micromachining applications.

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Influence of particulate morphology on microstructure and tribological properties of cold sprayed A380/Al2O3 composite coatings

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Journal of Materials science & Technology 2020年第9期44卷 9-18页

作者： Xiang Qiu Naeem ul Haq Tariq Lu Qi Jun-Rong Tang Xin-Yu Cui Hao Du Ji-Qiang Wang Tian-Ying Xiong Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Metallurgy and Materials Engineering Pakistan Institute of Engineering and Applied SciencesNiloreIslamabadPakistan

In this study,three kinds of A380/Al2O3 composite coatings were prepared by cold spray(CS)using spherical,irregular and spherical+irregular shaped Al2O3 particulates separately mixed in the original A380 alloy *** influence of Al2O3 particulates’morphology on the microstructural characteristics(*** of Al2O3 content in coatings,coating/matrix interfacial bonding,pore size distribution and morphology etc.)and wear performance of the coatings was investigated by scanning electron microscopy(SEM),X-ray computed tomography(XCT)and 3-D optical *** indicated that the spherical Al2O3 showsobvious tamping effect during deposition *** a result,the interfaceshowedawavy shape while the matrix and particulates were mechanical interlocked with much improved *** addition,the porosity of the coating was minimized and the pores exhibited curved spherical structure with reduced *** irregular Al2O3 particles predominantly displayed the embedding effect together with fragmentation of Al2O3 ***,poor coating/matrix interfacial bonding,high porosity and the formation of angular-shaped pores were resulted in the *** sliding wear tests results revealed that the wear resistance of the coating is directly related with the retained content of Al2O3 in the *** coating containing irregular Al2O3 particulates displayed superior wear performance with its wear rate one seventh of that of the pure A380 alloy *** coating containing both kinds of Al2O3 particulates showed mixed characteristics of above two kinds of Al2O3 composite coatings.

关键词： Cold spray Al2O3 particulates X-ray computed tomography Wear test

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Recent advancements in high-performance and durable electrodes materials for magnesium-ion batteries

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Coordination Chemistry Reviews 2025年 538卷

作者： Gohar, Osama Ishfaq, Hafiz Ahmad Iqbal, Muhammad Ahmad Khan, Muhammad Zubair Basharat, Sadia Kanwal, Nafeesa Riaz, Asad Saleem, Mohsin Koh, Jung-Hyuk Hussain, Iftikhar Akram, Muhammad Aftab Department of Mechanical and Electrical Systems Engineering Kyoto University of Advanced Science Gotanda-cho Yamanouchi Ukyo-ku Kyoto 615-8577 Japan Department of Materials Chemistry National Institute of Chemistry Hajdrihova 19 Ljubljana 1000 Slovenia Institute of Physics The Islamia University of Bahawalpur Baghdad ul Jadeed Campus Bahawalpur Pakistan Department of Materials Science & Engineering Pak-Austria Fachhochschule: Institute of Applied Sciences and Technology Mang Khyber Pakhtunkhwa Haripur 22621 Pakistan Center for Inorganic School of Chemistry University of the Punjab Quaid-e-Azam Campus Lahore 54590 Pakistan Department of Chemistry Quaid-i-Azam University Islamabad 45320 Pakistan Department of Mechanical Energy Management and Transportation Engineering School of Polytechnic University of Genova 16145 Italy School of Chemical and Materials Engineering (SCME) National University of Sciences and Technology (NUST) H-12 Islamabad 44000 Pakistan School of Electrical and Electronic Engineering Chung-Ang University Seoul South Korea Department of Mechanical Engineering City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong

Magnesium ion batteries (MIBs) are gaining traction as a viable alternative to lithium-ion batteries for large-scale energy storage due to their environmental sustainability, low cost, and high volumetric capacity. Despite these advantages, challenges such as sluggish Mg²⁺ ion de-intercalation, high polarization effects, and electrode incompatibility limit their commercial potential. To enhance MIB viability, developing stable, high-performance electrode materials is essential. This review presents recent advances in MIB electrode materials, focusing on both cathodes and anodes. The cathode materials reviewed include various intercalation compounds, such as Chevrel phase materials, chalcogenides, and layered structures, as well as spinel, olivine, NASICON-type, and emerging framework materials. Conversion-type cathodes, including sulfides, oxides, and redox-active organic materials, are discussed with emphasis on strategies for performance enhancement. Anodes explored include magnesium metal, alloy-based materials, and alternative compounds. This review highlights the recent advancements in MIB electrode materials over the past few years, outlining key opportunities and challenges. This work serves as a comprehensive resource for advancing MIB research and development. © 2025 Elsevier B.V.

关键词： Cathodes and anodes Electrodes materials Energy storage Magnesium-ion batteries Performance enhancement strategies

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Error rate performance of Hybrid QAM-FSK in OFDM systems exhibiting low PAPR

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science in China(Series F) 2009年第10期52卷 1875-1880页

作者： LATIF Asma GOHAR Nasir D. Pakistan Institute of Engineering and Applied Sciences P.O. Nilore Islamabad Pakistan NUST School of Electrical Engineering and Computer Science Islamabad Pakistan

Multicarrier transmission systems like orthogonal frequency division multiplexing （OFDM） support high data rate and generally require no equalization at the receiver, making them simple and efficient. This paper studies the design and performance analysis of a hybrid modulation system derived from multifrequency and MQAM signals, employed in OFDM. This modulation scheme has better bit error rate （BER） performance and exhibits low PAPR. The proposed hybrid modulator reduces PAPR while keeping the OFDM transceiver design simple, as it does not require any side information or a little side information （only one bit） to be sent and is efficient for arbitrary number of subcarriers. The results of the implementations are compared with those of conventional OFDM system.

关键词： orthogonal frequency division multiplexing (OFDM) hybrid MQAM/LFSK modulator (HQFM) bit error rate (BER) peak to average power ratio (PAPR)

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A study of different machine learning approaches for relation discovery task

A study of different machine learning approaches for relatio...

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International Conference on Energy, Power, Environment, Control and Computing (ICEPECC 2025)

作者： Fatima N. Al-Aswadi Wafa’ Za’al Alma’aitah Huah Yong Chan Keng Hoon Gan Zahid Iqbal Ahlam Al-Dhamari Institute of Computer Science and Digital Innovation UCSI University Kuala Lumpur 56000 Malaysia Department of Intelligence Systems Faculty of Artificial Intelligence Al-Balqa Applied University Salt 19117 Jordan School of Computer Sciences Universiti Sains Malaysia 11800 Gelugor Pulau Pinang Malaysia Department of Computer Science Air University Kharian Pakistan Department of Electrical and Computer Engineering Curtin University Malaysia Miri 98009 Sarawak Malaysia

ISBN: (数字)9781837243150

Relation extraction and classification, collectively referred to as relation discovery, are fundamental tasks in the ontology construction process. In recent years, numerous studies have dedicated their efforts to devising hybrid approaches, supporting inclusive innovation in computational linguistics and ontology engineering. These approaches merge traditional methods with Machine Learning (ML) or Deep Learning (DL) techniques to tackle relation discovery tasks. This research examines the applicability and efficacy of four distinct models—Support Vector Machine (SVM), Naive Bayes (NB), k-Nearest Neighbors (KNN), and Convolutional Neural Network (CNN)—in relation extraction and classification. Two different datasets, ACL RD-TEC 2.0 and ACLRelAcS, are utilized, alongside two distinct text representation methodologies, BOW and TF-IDF-BOW. An in-depth analysis of the results, including the advantages and limitations of each model, is presented in the results and discussion sections.

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A unified approach of energy and data cooperation in energy harvesting WSNs

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science China(Information sciences) 2018年第8期61卷 170-182页

作者： Roomana YOUSAF Rizwan AHMAD Waqas AHMED Fu-chun ZHENG School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Electrical Engineering Pakistan Institute of Engineering and Applied Sciences School of Electronic and Information Engineering Harbin Institute of Technology

Energy harvesting(EH) provisioned wireless sensor nodes are key enablers to increase network life time in modern wireless sensor networks(WSNs). However, the intermittent nature of the EH process necessitates management of nodes' limited data and energy buffer capacity. In this paper, a unified mathematical model for a cooperative EHWSN with an opportunistic relay is presented. The energy and data causality constraints are expressed in terms of throughput, available energy, delay and transmission *** finite energy buffers, data buffers and discrete transmission rates(as defined in the standard IEEE 802.15.4) at the nodes, different intuitive online power allocation policies at the relay are *** results show that a policy achieving high throughput is less fair and vice versa. Therefore, a joint rate and power allocation policy(JRPAP) is proposed in this study which provides a better trade off between fairness, throughput and energy over intuitive policies. Based on the JRPAP results, we propose to use data aggregation(DA) to achieve throughput gain at lower buffer sizes. In addition, the notion of energy aggregation(EA) is introduced to achieve throughput gain at higher buffer sizes. Combining both EA and DA further improves the overall throughput at all buffer sizes.

关键词： energy harvesting energy causality data causality energy aggregation data aggregation opportunistic relay

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Enhanced photosynthesis in Zea maize with the biofortification of ZIF-8 electron bridge to mediate growth improvement under drought

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Chemical engineering Journal 2025年 513卷

作者： Feng, Yingchen Zhang, Zhiyang Ding, Zixuan Chen, Ke Zhou, Zhenhao Ren, Xiaoqian Liang, Jinhua Huang, Yanan Shah, Anis Ali Li, Yuan Wu, Hongsheng Xiao, Qingbo Xu, Wenlong School of Ecology and Applied Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China Institute of Agricultural Resources and Environment Jiangsu Academy of Agricultural Sciences Nanjing210014 China Ministry of Agriculture and Rural Affairs Nanjing210014 China College of Environment and Safety Engineering Jiangsu University Zhenjiang212013 China College of Chemical Engineering Nanjing Tech University Nanjing211816 China College of Biological and Pharmaceutical Engineering Nanjing Tech University Nanjing211816 China Shang Hai Yeka Bio Technology CO. LTD Shanghai200949 China Department of Botany Division of Science and Technology University of Education Lahore Pakistan

Global climate change, threatening both rainfall patterns and temperature fluctuations, has made the frequency of drought major challenges for crop production worldwide. Under drought stress, the photosynthetic system can be degraded, leading to insufficient utilization of light-produced electrons, a retardation of their transfer rate through electron chains, and the accumulation of reactive oxygen species (ROS). In this work, ZIF-8, featuring coordinated unsaturated zinc sites and π bond ligand, is applied to modulate the leaked electrons transfer track and acts as a bridge to facilitate the utilization efficiency of excess electrons under drought stress in maize growth. With seed dressing using ZIF-8, root and shoot lengths increased by 57.9% and 11.9%, respectively, while root tips increased by 44.8% compared to both the control (CK) and ZnO treatment in pot trials with the soil moisture at 35% of field capacity. We believe this research establishes ZIF-8 as a promising nanomaterial for addressing agricultural challenges in a changing climate, providing a foundational framework for the development of engineered nanomaterials to enhance plant resilience. © 2025

关键词： Soil moisture

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Antibacterial Characterization of Silver Nanoparticles against *** ATCC-15224

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Journal of Materials science & Technology 2008年第2期24卷 192-196页

作者： M.Raffi F.Hussain T.M.Bhatti J.I.Akhter A.Hameed M.M.Hasan Department of Chemical and Materials Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)Islamabad-45650Pakistan Department of Microbiology Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabadPakistan Central Analytical Facility Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)Islamabad-45650Pakistan Physics Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)Islamabad-45650Pakistan

Silver nanoparticles of mean size 16 nm were synthesized by inert gas condensation （IGC） method. Crystalline structure, morphology and nanoparticles size estimation were conducted by X-ray diffraction （XRD） and transmission electron microscopy （TEM）. Antibacterial activity of these silver nanoparticles as a function of particles concentration against gram-negative bacterium Escherichia coli （E. coli） was carried out in liquid as well as solid growth media. Scanning electron microscopy （SEM） and TEM studies showed that silver nanoparticles after interaction with *** have adhered to and penetrated into the bacterial cells. Antibacterial properties of silver nanoparticles are attributed to their total surface area, as a larger surface to volume ratio of nanoparticles provides more efficient means for enhanced antibacterial activity.

关键词： Silver Nanoparticles Antibacterial Electron microscopy

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