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Plasma Science and Technology 2013年第9期15卷 900-903页

作者： h.i.a.qazi M.ShARiF S.hUSSAiN M.A.BADAR h.AFZAL Department of Physics University of SargodhaSargodha 40100Pakistan Department of Physics GC UniversityFaisalabad 38000Pakistan

This paper presents the fabrication and a spectroscopic study of a stable radio- frequency dielectric barrier discharge （RF DBD） in Ar with a novel dielectric, anodic alumina, at atmospheric pressure. Dielectric electrodes are fabricated from commercially available low cost impure aluminum strips by a two-step anodization process in 0.3 M solution of oxalic acid. The discharge is found to be stable with excellent spatial uniformity for the RF input power range of 30～80 W. Excitation and rotational temperatures measured in the experiment range of 1472～3255 K and 434～484 K, respectively, as the input power changes from 30 W to 80 W. These temperature ranges are suitable for surface modification applications.

关键词： radio frequency atmospheric pressure glow discharge dielectric barrier dis-charge anodic alumina dielectric

Electrical features of radio-frequency atmospheric pressure helium discharge with and without dielectric electrodes

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Plasma Science and Technology 2019年第2期21卷 60-67页

作者： h AShRAF S Z A ShAh h.i.a.qazi M A KhAN S hUSSAiN M A BADAR S NiAZ M ShAFiQ Department of Physics University of Sargodha Department of Physics Quaid-i-Azam University

A comparative study of radio-frequency atmospheric pressure glow discharge(rf APGD)generated in helium with and without dielectric electrodes to investigate the effect of electrodes insulation on electrical features of APGD is presented. in the α mode, both the rf APGDs remain volumetric, stable and uniform. in the γ mode, the APGD without dielectric electrodes shrinks into a constricted plasma column whereas APGD with dielectric electrodes remains stable and retains the same volume without plasma constriction even at higher densities of discharge current. A comparison of electrical features of both rf APGDs in normal and abnormal glow discharge regimes is presented. in both APGDs with and without dielectric electrodes,impedance measurements have been performed and compared with equivalent circuit *** measured impedance data is found to be in good agreement with simulated data.

关键词： radiofrequency atmospheric pressure glow discharge dielectric electrodes plasma stability control

Numerical Analysis of MhD Accelerator with Non-Equilibrium Air Plasma

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Plasma Science and Technology 2012年第12期14卷 1110-1115页

作者： M.ANWARi h.h.qazi SUKARSAN N.hARADA Electrical Engineering Department Umm Al-Qura University Faculty of Electrical Engineering Universiti Teknologi Malaysia Faculty of Electrical Engineering Universitas Islam "45" Bekasi Department of Electrical Engineering Nagaoka University of Technology

Magnetohydrodynamic （MhD） accelerator is proposed as a next generation propulsion system. it can be used to increase the performance of a propulsion system. The objective of this study is to investigate the performance of MhD accelerator using non-equilibrium air plasma as working gas. in this study, the fundamental performance of MhD accelerator such as flow performance and electrical performance is evaluated at different levels of applied magnetic field using i-D numerical simulation. The numerical simulation is developed based on a set of differential equations with MhD approximation. To solve this set of differential equations the MacCormack scheme is used. A specified channel designed and developed at NASA Marshall Space Flight Centre is used in the numerical simulation. The composition of the simulated air plasma consists of seven species, namely, N2, N, O2, O, NO, NO＋, and e-. The performance of the non-equilibrium MhD accelerator is also compared with the equilibrium MhD accelerator.

关键词： MhD accelerator Faraday type connection non-equilibrium air plasma

Spatio-temporal evolution characteristics and pattern formation of a gas–liquid interfacial AC current argon discharge plasma with a deionized water electrode

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Plasma Science and Technology 2021年第2期23卷 17-29页

作者： hafiz imran Ahmad qazi Muhammad Ajmal KhAN Jianjun hUANG SZU-CASiPP Joint Laboratory for Applied Plasma College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People's Republic of China Department of Engineering Physics Tsinghua UniversityBeijing 100084People's Republic of China

A discharge ignited by an AC power source in contact with deionized water as one of the electrodes is *** after initiation,the discharge exhibits a unique phenomenon:the gas-phase discharge is extended into the ***,a cone-like structure is observed at the liquid *** monitoring of current–voltage characteristics and liquid properties versus time suggests that the discharge shapes are functions of the liquid *** spatio-temporal profiles indicate the potential effects of water,ambient air impurities,and metastable argon on the discharge *** becomes more obvious near the liquid surface due to increasing production of various transient reactive species such as centerdot Oh and NO ***,it is revealed that thermalization of the rotational population distributions of the rotational states(N′⩽6,J′⩽13/2)in the Q1 branch of the Oh(A2Σ+,υ′=0→X2Π3/2,υ′′=0)band ro-vibrational system is influenced by the humid environment near the liquid *** addition,the transient behaviors of instantaneous concentrations of long-lived reactive species(LRS)such as h2O2,NO−2,and NO−3 are observed with lengthening the discharge *** production of multiple transient and LRS proposes AC excited gas–liquid argon discharge as a potential applicant in industrial wastewater cleaning,clinical medicine,and agriculture.

关键词： gas–liquid interface discharge emission patterns rotational temperature plasma chemistry

Effect of Salicylic Acid on Salinity-induced Changes in Brassica juncea

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Journal of integrative Plant Biology 2008年第9期50卷 1096-1102页

作者： Mohammad Yusuf Syed Aiman hasan Barket Ali Shamsul hayat qazi Fariduddin Aqil Ahmad Plant Physiology Section Department of Botany Aligarh Muslim University Department of Applied Sciences Higher College of Technology

Seeds of indian mustard （Brassicajuncea （L.） Czern. et Coss.） were exposed to 0, 50, 100 and 150 mmol/L NaCi for 8 h and seeds were sown in an earthen pot. These stressed seedlings were subsequently sprayed with 10μmol/L salicylic acid （SA） at 30 d and were sampled at 60 d to assess the changes in growth, photosynthesis and antioxidant enzymes. The seedlings raised from the seeds treated with NaCi had significantly reduced growth and the activities of carbonic anhydrase, nitrate reductase and photosynthesis, and the decrease was proportional to the increase in NaCi concentration. however, the antioxidant enzymes （catalase, peroxidase and superoxide dismutase） and proline content was enhanced in response to NaCi and/or SA treatment, where their interaction had an additive effect. Moreover, the toxic effects generated by the lower concentration of NaCi （50 mmol/L） were completely overcome by the application of SA. it was, therefore, concluded that SA ameliorated the stress generated by NaCl through the alleviated antioxidant system.

关键词： carbonic anhydrase catalase mustard net photosynthetic rate nitrate reductase peroxidase salicylic acid salinity superoxidedismutase.

Physicochemical properties of the AC- excited helium discharges using a water electrode

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Plasma Science and Technology 2018年第7期20卷 112-120页

作者： hafiz imran Ahmad qazi Yiying XiN Muhammad Ajmal KhAN heping Li Lu ZhOU Chengyu BAO Department of Engineering Physics Tsinghua University Beijing 100084 People's Republic of China School of Environment Tsinghua University Beijing 100084 People's Republic of China

in this paper, the AC-excited helium discharges generated between the powered needle electrode enclosed in a conical quartz tube and the grounded de-ionized water electrode are investigated. The current and voltage waveforms exhibit a transition from the glow-like to streamer-like mode discharges, which forms a stable cone-shaped structure at the gas-liquid interface. in this region, the air and water vapor diffusion initiate various physical-chemical processes leading to substantial changes of the primary species emission intensities （e.g., Oh, N2, NO, and O） and the rotational temperatures. The experimentally measured rotational temperature at the gas-liquid interface is 870 K from the Nz（C-B） band with a power input of 26 W. With the prolongation of the discharge time, significant changes in the discharge voltage and current, discharge emission patterns, instantaneous concentrations of the secondary species （e.g., h202, NO2, and NO3） in the liquid phase, ph values and electrical conductivities of the liquids are observed experimentally. The present study is helpful for deepening the understandings to the basic physical-chemical processes in the discharges in contact with liquids, especially to those occurring in the vicinity of the gas-liquid interface, and also for promoting existing and potential applications of such type of discharges in the fields of environmental protection, biomedicine, agriculture, and so on.

关键词： solution plasma gas-liquid interface wastewater treatment biomedical science and agriculture applications

Threefold Optimized Forecasting of Electricity Consumption in higher Education institutions

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Computers, Materials & Continua 2022年第11期73卷 2351-2370页

作者： Majida Kazmi hashim Raza Khan Lubaba Mohammad hashir Bin Khalid Saad Ahmed qazi Faculty of Electrical and Computer Engineering NED University of Engineering and TechnologyKarachi75270Pakistan Neurocomputation Lab National Center of Artificial IntelligenceKarachi75270Pakistan

Energy management benefits both consumers and utility companiesalike. Utility companies remain interested in identifying and reducing energywaste and theft, whereas consumers’ interest remain in lowering their energyexpenses. A large supply-demand gap of over 6 GW exists in Pakistan asreported in 2018. Reducing this gap from the supply side is an expensiveand complex task. however, efficient energy management and distributionon demand side has potential to reduce this gap economically. Electricityload forecasting models are increasingly used by energy managers in takingreal-time tactical decisions to ensure efficient use of resources. Advancementin Machine-learning (ML) technology has enabled accurate forecasting ofelectricity consumption. however, the impact of computation cost affordedby these ML models is often ignored in favour of accuracy. This studyconsiders both accuracy and computation cost as concurrently significantfactors because together they shape the technology environment as well ascreate economic impact. Thus, a three-fold optimized load forecasting modelis proposed which includes (1) application specific parameters selection, (2)impact of different dataset granularities and (3) implementation of specificdata preparation. it deploys and compares the widely used back-propagationArtificial Neural Network (ANN) and Random Forest (RF) models for theprediction of electricity consumption of buildings within a university. in addition to the temporal and historical power consumption date as input parameters, the study also embeds weather data as well as university operationalcalendars resulting in improved performance. The outcomes are indicativethat the granularity i.e. the scale of details in data, and set of reduced and fullinput parameters impact performance accuracies differently for ANN and RFmodels. Experimental results show that overall RF model performed betterboth in terms of accuracy as well as computational time for a 1-min, 15-minand 1-h dataset

关键词： Electricity forecasting short term higher educational institution artificial neural network random forest accuracy computational time

Classification of epilepsy using computational intelligence techniques

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CAAi Transactions on intelligence Technology 2016年第2期1卷 137-149页

作者： Khurram i. qazi h.K. Lam Bo Xiao Gaoxiang Ouyang Xunhe Yin Department of informatics King's College London Strand London WC2R 2LS United Kingdom State Key Laboratory of Cognitive Neuroscience and Learning School of Brain and Cognitive Sciences Beijing Normal University No.19 XinJieKoWai St Hai Dian District Beijing 100875 PR China School of Electronic and information Engineering Beijing Jiaotong University Beijing PR China

This paper deals with a real-life application of epilepsy classification, where three phases of absence seizure, namely pre-seizure, seizure and seizure-free, are classified using real clinical data. Artificial neural network （ANN） and support vector machines （SVMs） combined with su- pervised learning algorithms, and k-means clustering （k-MC） combined with unsupervised techniques are employed to classify the three seizure phases. Different techniques to combine binary SVMs, namely One Vs One （OvO）, One Vs All （OVA） and Binary Decision Tree （BDT）, are employed for multiclass classification. Comparisons are performed with two traditional classification methods, namely, k-Nearest Neighbour （k- NN） and Naive Bayes classifier. it is concluded that SVM-based classifiers outperform the traditional ones in terms of recognition accuracy and robustness property when the original clinical data is distorted with noise. Furthermore, SVM-based classifier with OvO provides the highest recognition accuracy, whereas ANN-based classifier overtakes by demonstrating maximum accuracy in the presence of noise.

关键词： Absence seizure Discrete wavelet transform Epilepsy classification Feature extraction k-means clustering k-nearest neighbours Naive Bayes Neuralnetworks Support vector machines

Combination of mesenchymal stem cells and three-dimensional collagen scaffold preserves ventricular remodeling in rat myocardial infarction model

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World Journal of Stem Cells 2022年第8期14卷 633-657页

作者： Rida-e-Maria qazi irfan Khan Kanwal haneef Tuba Shakil Malick Nadia Naeem Waqas Ahmad Asmat Salim Sadia Mohsin Stem Cell Laboratory Dr.Panjwani Center for Molecular Medicine and Drug ResearchICCBSUniversity of KarachiKarachi 75270SindhPakistan Dr.Zafar h.Zaidi Center for Proteomics University of KarachiKarachi 75270SindhPakistan Dow Research institute of Biotechnology and Biomedical Sciences(DRiBBS) Dow University of Health and SciencesOjha CampusKarachi 74200SindhPakistan Cardiovascular Research Center Lewis Katz School of MedicineTemple UniversityPhiladelphiaPA 19140United States

BACKGROUND Cardiovascular diseases are the major cause of mortality *** of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart *** tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac *** of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation *** stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of *** of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene *** To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo *** MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation *** were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different *** analysis was done and cardiac differentiation was analyzed at the gene and protein *** and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(Mi)model and cardiac function was assessed by *** tracking was performed by Dii dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,*** MSCs were successfully isolated and seeded in collagen *** analysis revealed that zebularine was not cytotoxic in any of the treatment *** differentiation analysis

关键词： Mesenchymal stem cells Myocardial infarction Cardiac tissue engineering Demethylating agent Collagen scaffold Zebularine

Using Model of a Universe as Similar to a Black hole, Ask if We have to have Singularities, if We Are Looking at initial Time Step and Entropy, from the Beginning

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Journal of high Energy Physics, Gravitation and Cosmology 2023年第3期9卷 708-719页

作者： Andrew Walcott Beckwith qazi Abdul Ghafoor Physics Department Chongqing University Chongqing China Mathematics Department Hazara University Mansehra Pakistan

Based on the idea of cyclic conformal cosmology, we formulate entropy and quantum number n, and then utilize the minimum uncertainty principle, where Delta E times Delta t equals h-bar, to actualize a prototype delta t time stop in the breakup of supermassive black holes into countless Planck mass-sized black holes. This helps to link entropy, time step, and primordial conditions and define when the cosmological constant may form and the initial inflationary expansion “speed”. All this is used to obtain a model of if a singularity, initially is needed.

关键词： inflation Fifth force Gravitational f Gravitons hubble Parameter