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Structural,Morphological and Electrical Properties of In-Doped Zinc Oxide Nanostructure Thin Films Grown on p-Type Gallium Nitride by Simultaneous radio-Frequency Direct-Current Magnetron Co-Sputtering

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Chinese Physics Letters 2016年第6期33卷 77-80页

作者： r.Perumal Z.Hassan r.Saravanan Institute of Nano-Optoelectronics research and Technology School of PhysicsUniversiti Sains Malaysia Department of Physics University College of Engineering PattukkottaiAnna University Chennai

Zinc oxide （ZnO） is one of the most promising and frequently used semiconductor materials. In-doped nanos- tructure ZnO thin films are grown on p-type gallium nitride substrates by employing the simultaneous rf and dc magnetron co-sputtering technique. The effect of In-doping on structural, morphological and electrical properties is studied. The different dopant concentrations are accomplished by varying the direct current power of the In target while keeping the fixed radio frequency power of the ZnO target through the co-sputtering deposition technique by using argon as the sputtering gas at ambient temperature. The structural analysis confirms that all the grown thin films preferentially orientate along the c-axis with the wurtzite hexagonal crystal structure without having any kind of In oxide phases. The presenting Zn, 0 and In elements＇ chemical compositions are identified with EDX mapping analysis of the deposited thin films and the calculated M ratio has been found to decrease with the increasing In power. The surface topographies of the grown thin films are examined with the atomic force microscope technique. The obtained results reveal that the grown film roughness increases with the In power. The Hall measurements ascertain that all the grown films have n-type conductivity and also the other electrical parameters such as resistivity,mobility and carrier concentration are analyzed.

关键词： ZnO of Structural,Morphological and Electrical Properties of In-Doped Zinc Oxide Nanostructure Thin Films Grown on p-Type Gallium Nitride by Simultaneous radio-Frequency Direct-Current Magnetron Co-Sputtering that by were been In EDX on

Numerical Simulation of Stall Flow Control Using a DBD Plasma Actuator in Pulse Mode

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Plasma Science and Technology 2016年第9期18卷 933-942页

作者： r.KHOSHKHOO A.JAHANGIrIAN Engineering Department Amirkabir University of Technology Tehran Ira

A numerical simulation method is employed to investigate the effects of the unsteady plasma body force over the stalled NACA 0015 airfoil at low reynolds number flow conditions. The plasma body force created by a dielectric barrier discharge actuator is modeled with a phenomenological method for plasma simulation coupled with the compressible Navier-Stokes equations. The governing equations are solved using an efficient implicit finitevolume method. The responses of the separated flow field to the effects of an unsteady body force in various inter- pulses and duty cycles as well as different locations and magnitudes are studied. It is shown that the duty cycle and inter-pulse are key parameters for flow separation control. Additionally, it is concluded that the body force is able to attach the flow and can affect boundary layer grow that Mach number 0.1 and reynolds number of 45000.

关键词： flow control, pulse plasma actuation unsteady flow, low reynolds number numerical simulation

Improving the charge kinetics through in-situ growth of NiSe nanoparticles on g-C_(3)N_(4)nanosheets for efficient hybrid supercapacitors

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Journal of Energy Chemistry 2023年第12期87卷 304-313,I0008页

作者： Somnath r.Khaladkar Oshnik Maurya Girish Gund Bhavesh Sinha Deepak Dubal r.r.Deshmukh Archana Kalekar Department of Physics Institute of Chemical Technology(ICT)MatungaMumbai 400019MaharashtraIndia Department of Physics Mahatma Phule ArtsScience and Commerce CollegePanvel 410206MaharashtraIndia National Center for Nanoscience and Nanotechnology University of MumbaiMumbai 400032MaharashtraIndia Centre for Materials Science School of Chemistry and PhysicsQueensland University of TechnologyBrisbane QLD 4000Australia

Nickel selenide(NiSe)has been a promising positive electrode for hybrid supercapacitors due to its multiple oxidation states,tunability,and high specific ***,sluggish ion transfers and particle agglomeration hamper its electrochemical *** the present study,we have grown NiSe nanoparticles on two-dimensional(2D)graphitic carbon nitride(g-C_(3)N_(4))nanosheets to realize three-dimensional(3D)*** 2D support,high nitrogen content,and features of g-C_(3)N_(4)enhanced the specific capacity of the NiSe/g-C_(3)N_(4)nanocomposite *** resulting nanocomposite shows a specific capacity of 320 mA h g^(-1)at a current density of 1 A g^(-1),which is considerably higher than pristine ***,the hybrid supercapacitor(HSC)device was fabricated using NiSe/g-C_(3)N_(4)composite as positive and activated carbon(AC)as negative *** cell delivered an energy density of 52.5 Wh kg^(-1)at a power density of 1488 W kg^(-1)with excellent cyclic stability of 84.9%over 8000 *** electrochemical performance enhancement corresponds to a 3D structure,high electrochemical active sites,and improved charge transportation at the electrode/electrolyte ***,the present work offers an easy approach and architectural design for high-performance HSC.

关键词： Nickel selenide Graphitic carbon nitride Nanocomposite Specific capacity Hybrid supercapacitor

Modified Black Widow Optimization-Based Enhanced Threshold Energy Detection Technique for Spectrum Sensing in Cognitive radio Networks

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2339-2356页

作者： r.Saravanan r.Muthaiah A.rajesh School of Computing SASTRA Deemed UniversityThanjavur613401India School of Electrical&Electronics Engineering SASTRA Deemed UniversityThanjavur613401India

This study develops an Enhanced Threshold Based Energy Detection approach(ETBED)for spectrum sensing in a cognitive radio *** threshold identification method is implemented in the received signal at the secondary user based on the square *** proposed method is implemented with the signal transmission of multiple outputs-orthogonal frequency division ***,the proposed method is considered the dynamic detection threshold adjustments and energy identification spectrum sensing technique in cognitive radio *** the dynamic threshold,the signal ratio-based threshold is *** threshold is computed by considering the Modified Black Widow Optimization Algorithm(MBWO).So,the proposed methodology is a combination of dynamic threshold detection and *** general threshold-based detection technique has different limitations such as the inability optimal signal threshold for determining the presence of the primary user *** limitations undermine the sensing accuracy of the energy identification ***,the ETBED technique is developed to enhance the energy efficiency of cognitive radio *** projected approach is executed and analyzed with performance and comparison *** proposed method is contrasted with the conventional techniques of theWhale Optimization Algorithm(WOA)and GreyWolf Optimization(GWO).It indicated superior results,achieving a high average throughput of 2.2 Mbps and an energy efficiency of 3.8,outperforming conventional techniques.

关键词： Cognitive radio network spectrum sensing noise uncertainty modified black widow optimization algorithm energy detection technique

Shock wave mitigation using zig-zag structures and cylindrical obstructions

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Defence Technology（防务技术） 2021年第6期17卷 1840-1851页

作者： Arun Kumar r Vaibhav Pathak Department of Mechanical Engineering Indian Institute of Technology Jodhpur(IITJ)JodhpurRajasthan342037India

The present study focuses on the mitigation of shock wave using novel geometric passages in the flow *** strategy is to produce multiple shock reflections and diffractions in the passage with minimum flow obstruction,which in turn is expected to reduce the shock wave strength at the target *** the present study the interaction of a plane shock front(generated from a shock tube)with various geometric designs such as,1)zig-zag geometric passage,2)staggered cylindrical obstructions and 3)zigzag passage with cylindrical obstructions have been investigated using computational *** is seen from the numerical simulation that,among the various designs,the maximum shock attenuation is produced by the zig-zag passage with cylindrical obstructions which is then followed by zig-zag passage and staggered cylindrical obstructions.A comprehensive investigation on the shock wave reflection and diffraction phenomena happening in the proposed complex passages have also been carried *** the new zig-zag design,the initial shock wave undergoes shock wave reflection and diffraction process which swaps alternatively as the shock front moves from one turn to the other *** cyclic shock reflection and diffraction process helps in diffusing the shock wave energy with practically no obstruction to the flow *** is found that by combining the shock attenuation ability of zig-zag passage(using shock reflection and diffraction)with the shock attenuation ability of cylindrical blocks(by flow obstruction),a drastic attenuation in shock strength can be achieved with moderate level of flow blocking.

关键词： Blast wave mitigation Blockage ratio Geometric obstructions Shock wave reflection and diffraction Zig-zag structure

Homogenization Theory for a replenishing Passive Scalar Field

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 631-644页

作者： Peter r. KrAMEr Shane r. KEATING Department of Mathematical Sciences Rensselaer Polytechnic Institute Center for Atmosphere-Ocean Science Courant Institute of Mathematical SciencesNew York University

Homogenization theory provides a rigorous framework for calculating the effective diffusivity of a decaying passive scalar field in a turbulent or complex *** authors extend this framework to the case where the passive scalar fluctuations are continuously replenished by a source (and/or sink).The basic structure of the homogenized equations carries over,but in some cases the homogenized source can involve a non-trivial coupling of the velocity field and the *** authors derive expressions for the homogenized source term for various multiscale source structures and interpret them physically.

关键词： Homogenization Turbulent transport Source Pumping

Novel acid initiators for the rapid cationic polymerization of styrene in room temperature ionic liquids

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Science China Chemistry 2012年第8期55卷 1671-1676页

作者： VIJAYArAGHAVAN r. MACFArLANE D. r. Department of Chemistry Monash University Clayton Campus Victoria 3800 Australia

Cationic polymerization of styrene has been achieved using several novel acidic initiators in room temperature ionic liquids (ILs) under mild reaction conditions to obtain polymers of low molecular weight with narrow polydispersity. Both strong protic acids such as bis(trifluoromethanesulfonyl) amide acid (HTFSA) and a moderately weak acid such as bisoxalato phosphorous acid (HBOP) have been studied as initiators. It has been observed that HTFSA initiates the polymerization rapidly even at room temperature and below, as compared to HBOP which produces a slower polymerization requiring elevated temperatures to complete. The relative difference in reactivity of the initiators as compared to the previously described HBOB initiator is discussed in terms of the difference in their proton acidity and the consequential basicity of the anions. The efficiency of different ILs as the reaction solvent is also presented.

关键词： cationic polymerization HTFSA HBOP ILs polydispersity

Detection of Osteoarthritis Based on EHO Thresholding

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Computers, Materials & Continua 2022年第6期71卷 5783-5798页

作者： r.Kanthavel r.Dhaya Kanagaraj Venusamy Department of Computer Engineering King Khalid UniversityAbhaSaudi Arabia Department of Computer Science King Khalid UniversitySarat Abidha CampusAbhaSaudi Arabia Department of Engineering University of Technology and Applied SciencesAl MussanahSultanate of Oman

Knee Osteoarthritis(OA)is a joint disease that is commonly observed in people around the *** commonly affects patients who are obese and those above the age of 60.A valid knee image was generated by Computed Tomography(CT).In this work,efficient segmentation of CT images using Elephant Herding Optimization(EHO)optimization is *** initial stage employs,the CT image normalization and the normalized image is incited to image enhancement through histogram ***,the enhanced image is segmented by utilizing Niblack and Bernsen ***(EHO)optimized outcome is evaluated in two *** initial step includes image enhancement with the measure of Mean square error(MSE),Peak signal to noise ratio(PSNr)and Structural similarity index(SSIM).The following step includes the segmentation which includes the measure ofAccuracy,Sensitivity and *** comparative analysis of EHO provides 95%of accuracy,94%of specificity and 93%of sensitivity than that of Active contour and Otsu threshold.

关键词： Osteoarthritis CT images correlation histogram thresholding Niblack&Bernsen algorithm EH optimization

role of simple biomarkers in predicting fibrosis progression in HCV infection

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World Journal of Gastroenterology 2010年第45期16卷 5710-5715页

作者： rajasekhara r Mummadi John r Petersen Ned Snyder Division of Gastroenterology and Hepatology Department of Internal MedicineUniversity of Texas Medical BranchHoustonTX 77025United States Department of Pathology University of Texas Medical BranchHoustonTX 77025United States Department of Gastroenterology and Hepatology Kelsey Seybold Clinic2727 W. HolcombeHoustonTX 77025United States

AIM: To examine the accuracy of the aspartate aminotransferase (AST)/Platelet ratio Index (APrI) and FIB-4, in predicting longitudinal changes in liver histology in hepatitis C virus (HCV) ***: Patients that underwent repeat liver biopsies at least 1 year apart from 1999 to 2007 were identified. Liver fibrosis was staged on needle core biopsies evaluated by a single expert liver pathologist. Only laboratory values within 3 mo of the liver biopsies were ***: Thirty-six patients met the inclusion criteria with 50% stage 1 on initial biopsy, 25% stage 2, and 22% stage 3. Nineteen of 36 (53%) had progression of fibrosis on repeat biopsies, while 16 (44%) showed no change in stage, and one (3%) showed improvement. Patients that showed progression of fibrosis had significantly higher alanine aminotransferase and aspartate aminotransferase levels than the group that did not show progression. A significant correlation was seen between change in stage of fibrosis and change in APrI (r2 = 0.39, P = 0.00001) and a change in FIB-4 (r2 = 0.31, P = 0.00004). A change in APrI (ΔAPrI) of 0.18 had 80% positive predictive value (PPV) and 67% nega- tive predictive value (NPV) for progression of fibrosis. A change in FIB-4 (ΔFIB-4) of 0.39 had 75% PPV and 75% NPV for predicting progression of fibrosis. CONCLUSION: ΔAPrI and ΔFIB-4 parallel changes in fibrosis progression, and could be useful tools for clinicians in following patients with active chronic HCV infection.

关键词： Hepatitis C Liver fibrosis Liver biopsy Biomarkers