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Nonplanar Ion-Acoustic Solitons in Electron-Positron-Ion Quantum Plasmas

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Chinese Physics Letters 2009年第4期26卷 150-153页

作者： S. A. Khan S. mahmood arshad m. mirza Department of Physics COMSATS Institute of Information Technology Islamabad Pakistan National Centre for Physics Quaid-i-Azam University Campus Islamabad Pakistan Department of Physics Government College Bagh AJK Pakistan Theoretical Plasma Physics Division PINSTECH PO Nilore Islamabad Pakistan Theoretical Plasma Physics Group Department of Physics Quaid-i-Azam University Islamabad 45320 Pakistan

The propagation of nonplanar quantum ion-acoustic solitary waves in a dense, unmagnetized electron-positronion （e-p-i） plasma are studied by using the Korteweg-de Vries （KdV） model. The quantum hydrodynamic （QHD） equations are used taking into account the quantum diffraction and quantum statistics corrections. The analytical and numerical solutions of KdV equation reveal that the nonplanar ion-acoustic solitons arc modified significantly with quantum corrections and positron concentration, and behave differently in different geometries.

关键词： SOLITONS ION acoustic waves QUANTUm theory PLASmA (Ionized gases) ELECTRONS POSITRONS KORTEWEG-de Vries equation EQUATIONS -- Numerical solutions

Nonplanar Ion Acoustic Solitary Waves in a Two-Electron Temperature Plasma

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Chinese Physics Letters 2009年第12期26卷 73-76页

作者： W. masood S. Hussain S. mahmood arshad m. mirza Theoretical Plasma Physics Division Pinstech P. O. Nilore Islamabad Pakistan Pakistan Institute of Engineering and Applied Sciences (PLEAS) P. O. Nilore Islamabad Pakistan Theoretical Plasma Physics Group Department of Physics Quaid-i-Azam University Islamabad 45320 Pakistan

Linear and non-linear properties of ion acoustic wave （IAW） propagating in a two-electron temperature plasma are investigated from both analytical and numerical perspectives by employing the fluid theory. A one-dimensional modified Korteweg de Vries equation is derived for the IAW using the reductive perturbative technique in a nonplanar geometry. It is observed that the ion acoustic soliton in a two-temperature plasma admits rarefactive （dip like） solitons. In the limit that the cold electron population goes to zero, it is observed that the ion acoustic soliton yields compressive （hump like） solitons. The variation of the ion acoustic soliton with different plasma parameters is also shown. The present investigation may be beneficial to explain some aspects of ion acoustic rarefactive solitary structures observed in space environments where two-electron temperature plasmas have been observed.

关键词： Chinese climate network complex systems small world community

Effect of Acoustic Resonance Phenomenon on Fluid Flow with Light Dust

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Journal of Thermal Science 2011年第5期20卷 430-434页

作者： Hiromitsu Hamakawa Azim B.m.arshad mitsuo Ohta Department of mechanical Engineering Oita University Graduate Student Oita University

In the present paper,the attention is focused on the characteristics of lightweight materials collection in the duct using acoustic resonance *** acoustic resonance was excited by using a controlled speaker at the middle of a test *** measured the sound pressure level,frequency response characteristics,acoustic damping ratio,mode shape,and lightweight materials response to acoustic resonance excited by a *** a result,the acoustic damping ratio decreased as the mode number of acoustic resonance *** tissue strips and the lightweight materials were collected at the node of acoustic pressure when the acoustic resonance was *** was made clear that it is possible to control lightweight materials using acoustic resonance excited by a speaker.

关键词： Acoustic Excitation Acoustic Dust Filter Visualization Acoustic Damping Duct Flow

Inoculation with Pseudomonas spp. Containing ACC-Deaminase Partially Eliminates the Effects of Drought Stress on Growth,Yield,and Ripening of Pea (Pisum sativum L.)

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Pedosphere 2008年第5期18卷 611-620页

作者： m. arshad B. SHAHAROONA T. mAHmOOD Institute of Soil & Environmental Sciences University of AgricultureFaisalabad-38040(Pakistan) Department of Agronomy University of Arid AgricultureRawalpindi(Pakistan)

Two preselected plant growth promoting rhizobacteria(PGPR) containing 1-aminocyclopropane-1-carboxylate(ACC) -deaminase(EC 4.***.99.4) were used to investigate their potential to ameliorate the effects of drought stress on growth,yield,and ripening of pea(Pisum sativum L.) . Inoculated and uninoculated(control) seeds of pea cultivar 2000 were sown in pots(four seeds pot-1) and placed in a wire house. The plants were exposed to drought stress at different stages of growth(vegetative,flowering,and pod formation) by skipping the respective irrigation. Results revealed that inoculation of peas with PGPR containing ACC-deaminase significantly decreased the "drought stress imposed effects" on the growth and yield of peas. Exposure of plants to drought stress at vegetative growth stage significantly decreased shoot growth by 41% in the case of uninoculated plants,whereas,by only 18% in the case of inoculated plants compared to nonstressed uninoculated control. Grain yield was decreased when plants were exposed to drought stress at the flowering and pod formation stage,but inoculation resulted in better grain yield(up to 62% and 40% higher,respectively) than the respective uninoculated nonstressed control. Ripening of pods was also delayed in plants inoculated with PGPR,which may imply decreased endogenous ethylene production in inoculated plants. This premise is further supported by the observation that inoculation with PGPR reduced the intensity of classical "triple" response in etiolated pea seedlings,caused by externally applied ACC. It is very probable that the drought stress induced inhibitory effects of ethylene could be partially or completely eliminated by inoculation with PGPR containing ACC-deaminase.

关键词： ACC-deaminase drought stress plant growth rhizobacteria ripening

Diffusion of Six-Atom Cu Islands on Cu(111)and Ag(111)

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Chinese Physics Letters 2011年第5期28卷 99-102页

作者： Sardar Sikandar Hayat I.Ahmad m.arshad Choudhry Department of Physics and Astronomy Hazara UniversityMansehra 23100Pakistan Department of Physics The Islamia University of BahawalpurBahawalpur 63120Pakistan

Diffusion of Cu hexamer islands on Cu(111)and Ag(111)is studied using a molecular dynamics simulation technique with many-body potentials obtained from the embedded atom *** are carried out at temperatures 300,500 and 700 K,showing that shape-changing multiple-atom processes are more helpful for the diffusion rather than concerted motion of *** plots of the diffusion coefficients provide effective energy barrier values of 161.29±5 meV for Cu(111)and 179.34±5 meV for Ag(111)*** 700K,one pop-up atom among island atoms is observed with correlative changes in the position and shape of the lower-layer adatoms.

关键词： Cu(111) method Diffusion

Structural and spectroscopic analysis of wurtzite（ZnO）1-x（Sb2O3）x composite semiconductor

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Progress in Natural Science:materials International 2015年第2期25卷 131-136页

作者： Hafeez ullah Amjid Iqbal m. Zakria arshad mahmood University of Trento Department of Physics Via Sommarive 14 Povo 38123 Trento Italy Center for materials and microsystems Fondazione Bruno Kessler Via Sommarive 18 Povo 38123 Trento Italy National Institute of Lasers and Optronics (NILOP) Nilore Islamabad Pakistan

The structural, vibrational and impedance analysis for(Zn O)1 x(Sb2O3)xcomposite synthesized by solid state reaction technique were carried out in the present investigation. X-ray diffraction(XRD) study showed that(Zn O)1 x(Sb2O3)xcomposite has hexagonal(wurtzite) crystal structure. Variation in lattice constants with Sb-doping indicated the proper incorporation of Sb dopant in Zn O host matrix. The results of Raman spectroscopy test suggested the signature of E2(high) and E1(TO) Raman modes, and verified the wurtzite structure of(Zn O)1 x(Sb2O3)x composite. Two additional phonon bands(671, 712) cm 1appeared in Raman spectra of composite samples due to the existence of the lattice defects caused by Sb doping or may be other intrinsic lattice defects formed during the synthesis of(Zn O)1 x(Sb2O3)xcomposite. The frequency dependent on the electrical characteristics, such as, impedance(Z), dielectric constant(ε) and AC conductivity(σ) have been studied in a range of frequencies for different Sb concentration at room temperature. The electrical measurement results showed that the impedance increased with Sb dopant concentration, while dielectric constant and AC conductivity decreased with Sb dopant concentration.

关键词： (Zn O)1 x(Sb2O3)x Semiconductors XRD Raman spectroscopy Impedance spectroscopy

Non-Intrusive monitoring of Everyday Behavioral Activities in an Indoor Environment

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Journal of Electronic Science and Technology 2016年第3期14卷 205-210页

作者： Atika arshad Sheroz Khan A.H.m.Zahirul Alam Rumana Tasnim Department of Electrical and Computer Engineering International Islamic University MalaysiaKuala Lumpur 53100Malaysia Department of mechatronics Engineering World University of BangladeshDhaka 1205Bangladesh

A non-intrusive design for monitoring everyday activities of an elderly person is presented. The proposed system is intended to be used in the bedroom, allowing the elders to stay at home in a safe environment. The required hardware design is simple in structure and cost effective. The sensor design is implemented by using capacitive sensors and an Arduino microcontroller unit. And a real time graphical user interface is implemented to monitor the elderly person. The performance analysis shows that the sensor design is able to differentiate between a human body and a house pet.

关键词： Index Terms-Arduino elderly home sensors senior citizens.

Oviposition preference of swallowtail butterfly, Papilio polytes （Lepidoptera Papilionidae） on four Rutaceae （Sapindales） host plant species

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Insect Science 2010年第4期17卷 369-378页

作者： Suwarno m.R. Che Salmah arshad Ali A. Abu Hassan School of Biological Sciences Universiti Sains Malaysia 11800 Penang Malaysia Department of Biology Faculty of Science University Syiah Kuala 23111 Banda Aceh Indonesia University of Florida IFAS. Mid-Florida Research and Education Center 2725 Binion Road Apopka FL 32703-8504 USA

Oviposition preference and egg deposition site selection by the butterfly, Papilio polytes L. （Lepidoptera： Papilionidae） on four rutaceous host plants, Citrus aurantofolia （Christm.） Swing., Citrus hystrix DC., Citrus reticulata Blanco, and murraya koenigii （L.） Sprengel, were assessed in field cages measuring 2 × 2 ×2 m. Simultaneous two-choice and four-choice oviposition tests of whole host plants were conducted. The mean total number of eggs laid per plant on C. reticulata in the two-choice test was significantly higher （P 〈 0.01） than those on C. aurantifolia, C. hystrix, andm. koenigii. Among the three other host plants, C. aurantifolia was preferred over C. hystrix, and m. koenigii （P 〈 0.01） and C. hystrix was preferred over m. koenigii （P 〈 0.01）. In the four-choice test, C. reticulata was highly preferred and significantly different from C. hystrix and m. koenigii. However, no oviposition preference was detected with C. aurantifolia. Among the various plant parts in the two- and four-choice tests, eggs on leaves of each plant were the highest, followed by numbers on stems, and negligible numbers on pots. These numbers on leaves of C. reticulata and C. aurantifolia were not significantly different （P 〉 0.05）, but differed significantly （P 〈 0.01） from those on leaves of C. hystrix and m. koenigii. The quantitative trend of egg-laying on stems was very similar to that observed for the leaves. Papilio polytes showed strong preference to lay eggs on the underside of leaves of all host plants than on the upper side or on the petiole. more eggs were laid on the upper side of each host plant than on its petiole. The four host plants in descending order of preference were C. reticulata 〉 C. aurantifolia 〉 C. hystrix 〉 m. koenigii. Although m. koenigii was the least preferred, it has the potential to serve as an alternative host plant for P. polytes which can be manipulated when necessary, to alleviate the infestation of this pest to the citrus industry.

关键词： Citrus aurantifolia Citrus hystrix Citrus reticulata murraya koenigii ovipo-sition preference Papilio polytes

Tuning structural,electrical,dielectric and magnetic properties of mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： maria Akhtar m.S.Hasan Nasir Amin N.A.morley muhammad Imran arshad Department of Physics Government College UniversityFaisalabad38000Pakistan Department of Physics The University of Lahore53700Pakistan Department of materials Science and Engineering The University of SheffieldS13JDUK Department of Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(SEm),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSm)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped mCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths