Engineering Commons^™

On The Chronological Understanding Of The Homogeneous Dielectric Barrier Discharge, Xinpei Lu, Zhi Fang, Dong Dai, Tao Shao, Feng Liu, Cheng Zhang, Dawei Liu, Chunqi Jiang

Electrical & Computer Engineering Faculty Publications

Dielectric barrier discharges (DBD) are widely utilised non-equilibrium atmospheric pressure plasmas with a diverse range of applications, such as material processing, surface treatment, light sources, pollution control, and medicine. Over the course of several decades, extensive research has been dedicated to the generation of homogeneous DBD (H-DBD), focussing on understanding the transition from H-DBD to filamentary DBD and exploring strategies to create and sustain H-DBD. This paper first discusses the influence of various parameters on DBD, including gas flow, dielectric material, surface conductivity, and mesh electrode. Secondly, a chronological literature review is presented, highlighting the development of H-DBD and the …

On The Chronological Understanding Of The Homogeneous Dielectric Barrier Discharge, Xinpei Lu, Zhi Fang, Dong Dai, Tao Shao, Feng Liu, Cheng Zhang, Dawei Liu, Lanlan Nie, Chunqi Jiang

Bioelectrics Publications

Dielectric barrier discharges (DBD) are widely utilised non-equilibrium atmospheric pressure plasmas with a diverse range of applications, such as material processing, surface treatment, light sources, pollution control, and medicine. Over the course of several decades, extensive research has been dedicated to the generation of homogeneous DBD (H-DBD), focussing on understanding the transition from H-DBD to filamentary DBD and exploring strategies to create and sustain H-DBD. This paper first discusses the influence of various parameters on DBD, including gas flow, dielectric material, surface conductivity, and mesh electrode. Secondly, a chronological literature review is presented, highlighting the development of H-DBD and the …

Nb₃Sn Coating Of A 2.6 Ghz Srf Cavity By Sputter Deposition Technique, M. S. Shakel, Wei Cao, H. Elsayed-Ali, G. V. Eremeev, U. Pudasaini, A. M. Valente-Feliciano

Electrical & Computer Engineering Faculty Publications

Nb₃Sn is of interest as a coating for SRF cavities due to its higher transition temperature Tc ~18.3 K and superheating field Hsh ~400 mT, both are twice that of Nb. Nb₃Sn coated cavities can achieve high-quality factors at 4 K and can replace the bulk Nb cavities operated at 2 K. A cylindrical magnetron sputtering system was built, commissioned, and used to deposit Nb₃Sn on the inner surface of a 2.6 GHz single-cell Nb cavity. With two identical cylindrical magnetrons, this system can coat a cavity with high symmetry and uniform thickness. Using Nb-Sn multilayer sequential sputtering followed by …

In Vivo Metabolic Analysis Of The Anticancer Effects Of Plasma-Activated Saline In Three Tumor Animal Models, Miao Qi, Dehui Xu, Shuai Wang, Bing Li, Sansan Peng, Qiaosong Li, Hao Zhang, Runze Fan, Hai-Lan Chen, Michael G. Kong

Bioelectrics Publications

In recent years, the emerging technology of cold atmospheric pressure plasma (CAP) has grown rapidly along with the many medical applications of cold plasma (e.g., cancer, skin disease, tissue repair, etc.). Plasma-activated liquids (e.g., culture media, water, or normal saline, previously exposed to plasma) are being studied as cancer treatments, and due to their advantages, many researchers prefer plasma-activated liquids as an alternative to CAP in the treatment of cancer. In this study, we showed that plasma-activated-saline (PAS) treatment significantly inhibited tumor growth, as compared with saline, in melanoma, and a low-pH environment had little effect on tumor growth in …

A Simple Gas-Kinetic Model For Dilute And Weakly Charged Plasma Micro-Jet Flows, Shiying Cai, Chunpei Cai

Michigan Tech Publications

This paper presents a simple model for slightly charged gas expanding into a vacuum from a planar exit. The number density, bulk velocity, temperature, and potential at the exit are given. The electric field force is assumed weaker than the convection term and is neglected in the analysis. As such, the quasi-neutral condition is naturally adopted and the potential field is computed with the Boltzmann relation. At far field, the exit degenerates as a point source, and simplified analytical formulas for flow and electric fields are obtained. The results are generic and offer insights on many existing models in the …

Steam Oxidation Of Ytterbium Disilicate Environmental Barrier Coatings With And Without A Silicon Bond Coat, Ken A. Kane, Eugenio Garcia, Sharon Uwanyuze, Michael Lance, Kinga A. Unocic, Sanjay Sampath, Bruce A. Pint

Materials Science and Engineering Faculty Research & Creative Works

The current generation of multilayer Si/Yb₂Si₂O₇ environmental barrier coatings (EBCs) are temperature limited by the melting point of Si, 1414°C. To investigate higher temperature EBCs, the cyclic steam oxidation of EBCs comprised of a single layer of ytterbium disilicate (YbDS) was compared to multilayered Si/YbDS EBCs, both deposited on SiC substrates using atmospheric plasma spray. After 500 1-h cycles at 1300°C in 90 vol%H₂O-10 vol%air with a gas velocity of 1.5 cm/s, both multilayer Si/YbDS and single layer YbDS grew thinner silica scales than bare SiC, with the single layer YbDS forming the …

Modulation Of Ros In Nanosecond-Pulsed Plasma-Activated Media For Dosage-Dependent Cancer Cell Inactivation In Vitro, Chunqi Jiang, Esin Bengisu Sozer, Shutong Song, Nicola Lai, P. Thomas Vernier, Sigi Guo

Bioelectrics Publications

Dosage control of reactive oxygen and nitrogen species (RONS) is critical to low-temperature plasma applications in cancer therapy. Production of RONS by atmospheric pressure, nonequilibrium plasmas in contact with liquid may be modulated via plasma conditions including plasma treatment time and pulse voltage and repetition frequency. In this study, a terephthalic acid-based probe was used to measure hydroxyl radicals [OH_aq] in water exposed to plasma and to demonstrate that the OH_ag concentration increases linearly with treatment time. Fluorometric measurements of hydrogen peroxide concentration in plasma-activated water show a linear relationship between the H₂O₂ production …

Plasma And Serum Proteins Bound To Nanoceria: Insights Into Pathways By Which Nanoceria May Exert Its Beneficial And Deleterious Effects In Vivo, D. Allan Butterfield, Binghui Wang, Peng Wu, Sarita S. Hardas, Jason M. Unrine, Eric A. Grulke, Jian Cai, Jon B. Klein, William M. Pierce, Robert A. Yokel, Rukhsana Sultana

Chemistry Faculty Publications

Nanoceria (CeO2, cerium oxide nanoparticles) is proposed as a therapeutic for multiple disorders. In blood, nanoceria becomes protein-coated, changing its surface properties to yield a different presentation to cells. There is little information on the interaction of nanoceria with blood proteins. The current study is the first to report the proteomics identification of plasma and serum proteins adsorbed to nanoceria. The results identify a number of plasma and serum proteins interacting with nanoceria, proteins whose normal activities regulate numerous cell functions: antioxidant/detoxification, energy regulation, lipoproteins, signaling, complement, immune function, coagulation, iron homeostasis, proteolysis, inflammation, protein folding, protease inhibition, adhesion, protein/RNA …

High Heat Flux Testing Facilities And An Electrothermal-Arc Plasma Source For Plasma-Material Interaction Studies And Diagnostic Development, Elizabeth G. Lindquist

Faculty Publications and Other Works -- Nuclear Engineering

Tokamak plasma-facing components experience significant stresses from plasma-material interactions (PMI) due to cyclic high thermal loads, plasma exposure, and neutron irradiation. As the field progresses to reactor-level power fluxes, the harsh fusion environment demands much of plasma-facing materials.

Chapter 1 introduces plasma-material interactions and the condition plasma-facing components are expected to endure. While plasma exposure and neutron radiation damage are introduced, the synergistic effects of cyclic high thermal loads under plasma exposure are focused on. This motivates the need for plasma-facing materials studies.

Chapter 2 gives a brief overview of many high heat flux test facilities worldwide. Three prominent high …

Understanding The Effects Of Plasma Assisted Nanoparticle Deposition For The Enhancement Of Optical And Electrochemical Response, Apurva Sonawane

FIU Electronic Theses and Dissertations

In this work, the effects of atmospheric plasma treatment on morphology, optical, and electrochemical properties of 10 ± 3nm spherical silver and gold nanoparticles (AgNPs and AuNPs) functionalized substrates were studied. The nanoparticles (NPs) were deposited on substrates by drop-casting, aerosol spray, and a low-temperature atmospheric plasma-assisted aerosol jet. The reduction in nanoparticle size was observed, which was explained by the redox reaction that occurs on the nanoparticle surface. This phenomenon was evident by the presence of AgO, Ag₂O, and AuO_x Raman peaks in the treated sample. The surface charge changed as a result of plasma treatment, …

Femtosecond Photon-Mediated Plasma Enhances Photosynthesis Of Plasmonic Nanostructures And Their Sers Applications, Peng Ran, Lan Jiang, Xin Li, Bo Li, Pei Zuo, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Laser ablation in liquid has proven to be a universal and green method to synthesize nanocrystals and fabricate functional nanostructures. This study demonstrates the superiority of femtosecond laser-mediated plasma in enhancing photoredox of metal cations for controllable fabrication of plasmonic nanostructures in liquid. Through employing upstream high energetic plasma during laser-induced microexplosions, single/three-electron photoreduction of metallic cations can readily occur without chemical reductants or capping agents. Experimental evidences demonstrate that this process exhibits higher photon utilization efficiency in yield of colloidal metal nanoparticles than direct irradiation of metallic precursors. Photogenerated hydrated electrons derived from strong ionization of silicon and water …

Atmospheric Pressure Plasma‐Induced Decolorisation Of Cotton Knitted Fabric Dyed With Reactive Dye, Yaohui Liu, Chester Kin-Man To, Mei‐Ki Ngai, Chi-Wai Kan, Chua Hong

Faculty of Science & Technology (THEi)

The aim of this study was to investigate the decolorisation effect of atmospheric pressure plasma treatment on knitted fabrics dyed with reactive dyes under different processing parameters, ie, air concentration, treatment duration and water content. The fabrics were dyed with reactive dye of a blue colour, and the colour depths were 0.5%, 1.5% and 3.0% on weight of fabric. The colour properties of untreated and plasma‐treated fabric samples were evaluated by means of reflectance, K/S and relative unlevelness index. The colour properties were evaluated instrumentally and quantitatively in order to study the decolorisation effect induced by atmospheric pressure plasma treatment. …

Correcting For Targeted And Control Agent Signal Differences In Paired-Agent Molecular Imaging Of Cancer Cell-Surface Receptors, Negar Sadeghipour, Scott C. Davis, Kenneth M. Tichauer

Dartmouth Scholarship

Paired-agent kinetic modeling protocols provide one means of estimating cancer cell-surface receptors with in vivo molecular imaging. The protocols employ the coadministration of a control imaging agent with one or more targeted imaging agent to account for the nonspecific uptake and retention of the targeted agent. These methods require the targeted and control agent data be converted to equivalent units of concentration, typically requiring specialized equipment and calibration, and/or complex algorithms that raise the barrier to adoption. This work evaluates a kinetic model capable of correcting for targeted and control agent signal differences. This approach was compared with an existing …

Laser Shock Wave Assisted Patterning On Niti Shape Memory Alloy Surfaces, Dovletgeldi Seyitliyev, Peizhen Li, Khomidkhodza Kholikov, Byron Grant, Haluk E. Karaca, Ali O. Er

Mechanical Engineering Faculty Publications

An advanced direct imprinting method with low cost, quick, and less environmental impact to create thermally controllable surface pattern using the laser pulses is reported. Patterned micro indents were generated on Ni₅₀Ti₅₀ shape memory alloys (SMA) using an Nd:YAG laser operating at 1064 nm combined with suitable transparent overlay, a sacrificial layer of graphite, and copper grid. Laser pulses at different energy densities which generates pressure pulses up to 10 GPa on the surface was focused through the confinement medium, ablating the copper grid to create plasma and transferring the grid pattern onto the NiTi surface. Scanning …

Preface To Special Topic: A Tribute To John Lumley, Kiran Bhaganagar, Thomas B. Gatski, William K. George

CCPO Publications

This Special Topic Section is dedicated to the life and memory of John Leask Lumley(1930-2015), professor and scientist extraordinaire.

Short Oxygen Plasma Treatment Leading To Long-Term Hydrophilicity Of Conductive Pcl-Ppy Nanofiber Scaffolds, Sajjad Shafei, Javad Foroughi, Zhiqiang Chen, Cynthia S. Wong, Minoo Naebe

Australian Institute for Innovative Materials - Papers

No abstract provided.

Microstructure Refinement In W-Y2o3 Alloy Fabricated By Wet Chemical Method With Surfactant Addition And Subsequent Spark Plasma Sintering, Zhi Dong, Nan Liu, Zongqing Ma, Chenxi Liu, Qianying Guo, Zeid Abdullah Alothman, Yusuke Yamauchi, Md. Shahriar Al Hossain, Yongchang Liu

Australian Institute for Innovative Materials - Papers

With the aim of preparing high performance oxide-dispersion-strengthened tungsten based alloys by powder metallurgy, the W-Y 2 O 3 composite nanopowder precursor was fabricated by an improved wet chemical method with anion surfactant sodium dodecyl sulfate (SDS) addition. It is found that the employment of SDS can dramatically decrease W grain size (about 40 nm) and improve the size uniformity. What's more, SDS addition can also remarkably improve the uniform dispersion of Y 2 O 3 particles during the synthesis process. For the alloy whose powder precursor was fabricated by traditional wet chemical method without SDS addition, only a few …

Influence Of Oxygen Plasma Treatment Parameters On Poly(Vinylidene Fluoride) Electrospun Fiber Mats Wettability, Daniela M. Correia, Clarisse Ribeiro, Vitor Sencadas, Gabriela Botelho, S A. Carabineiro, J L. Gomez Ribelles, Senentxu Lanceros-Méndez

Faculty of Engineering and Information Sciences - Papers: Part A

Electrospun poly(vinylidene fluoride) (PVDF) fiber mats found applications in an increasing number of areas, such as battery separators, filtration and detection membranes, due to their excellent properties. However, there are limitations due to the hydrophobic nature and low surface energy of PVDF. In this work, oxygen plasma treatment has been applied in order to modify the surface wettability of PVDF fiber mats and superhydrophilic PVDF electrospun membranes have been obtained. Further, plasma treatment does not significantly influences fiber average size (~400 ± 200 nm), morphology, electroactive B-phase content (~80-85%) or the degree of crystallinity (Xc of 42 ± 2%), allowing …

Effects Of Plasma Processing On Secondary Electron Yield Of Niobium Samples, M. Basovic, S. Popovic, M. Tomovic, L. Vuskovic, A. Samolov, F. Cuckov

Physics Faculty Publications

Impurities deposited on the surface of Nb during both the forming and welding of accelerator cavities add to the imperfections of the sheet metal, which then affects the overall performance of the cavities. This leads to a drop in the Q factor and limits the maximum acceleration gradient achievable per unit length of the cavities. The performance can be improved either by adjusting the fabrication and preparation parameters, or by mitigating the effects of fabrication and preparation techniques used. We have developed the experimental setup to determine Secondary Electron Yield (SEY) from the surface of Nb samples. Our aim is …

High Throughput Extraction Of Plasma Using A Secondary Flow-Aided Inertial Microfluidic Device, Jun Zhang, Sheng Yan, Weihua Li, Gursel Alici, Nam-Trung Nguyen

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we report the development of a simple inertial microfluidic device with a serpentine channel for efficiently separating blood cells from plasma. The working mechanism of this device relies on the two-sided secondary flow aided inertial focusing of particles in a serpentine channel. Specifically, blood cells were focused along two sides of the channel, while the blood plasma was collected at the cell-free region within the channel centre. The device was tested with diluted (1/20) whole blood. A relatively high flow rate of 350 μl min−1 with a purity of [similar]99.75% was achieved in a single process. A …

A Comparative Study For Wear Resistant Of Stellite 6 Coatings On Nickel Alloy Substrate Produced By Laser Cladding, Hvof And Plasma Spraying Techniques, Alain Kusmoko, Druce P. Dunne, Huijun Li

Faculty of Engineering and Information Sciences - Papers: Part A

Stellite 6 coatings were deposited using laser cladding, high velocity oxygen fuel (HVOF) thermal spraying and plasma spraying techniques on a nickel alloy substrate. The surface roughness, chemical composition and microstructure of these coatings were characterised by a surface profilometer, optical microscopy (OM) and scanning electron microscopy (SEM). The microhardness of the coatings was measured and the wear behaviour of the coatings was examined under controlled test conditions in a pin-on-plate (reciprocating) tribometer. The results showed that fully dense and crack-free laser clad Stellite 6 coatings can be formed on a high nickel steel substrate. Average microhardness values of the …

Isolating Plasma From Blood Using A Dielectrophoresis-Active Hydrophoretic Device, Sheng Yan, Jun Zhang, Gursel Alici, Haiping Du, Yonggang Zhu, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

Plasma is a complex substance that contains proteins and circulating nucleic acids and viruses that can be utilised for clinical diagnostics, albeit a precise analysis depends on the plasma being totally free of cells. We proposed the use of a dielectrophoresis (DEP)-active hydrophoretic method to isolate plasma from blood in a high-throughput manner. This microfluidic device consists of anisotropic microstructures embedded on the top of the channel which generate lateral pressure gradients while interdigitised electrodes lay on the bottom of the channel which can push particles or cells into a higher level using a negative DEP force. Large and small …

Defects Induced Ferromagnetism In Plasma-Enabled Graphene Nanopetals, Zengji Yue, Donghan Seo, Kostya Ostrikov, Xiaolin Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Ferromagnetism in graphene is fascinating, but it is still a big challenge for practical applications due to the weak magnetization. In order to enhance the magnetization, here, we design plasma-enabled graphene nanopetals with ultra-long defective edges of up to 105 m/g, ultra-dense lattice vacancies, and hydrogen chemisorptions. The designed graphene nanopetals display robust ferromagnetism with large saturation magnetization of up to 2 emu/g at 5 K and 1.2 emu/g at room temperatures. This work identifies the plasma-enabled graphene nanopetals as a promising candidate for graphene-based magnetic devices. 2014 AIP Publishing LLC.

Zein Film: Effects Of Dielectric Barrier Discharge Atmospheric Cold Plasma, Shashi Pankaj, Carmen Bueno-Ferrer, N. Misra, Paula Bourke, Patrick Cullen

Articles

Dielectric barrier discharge atmospheric plasma is a novel non-thermal technology for the food and packaging industry. The effects of dielectric barrier discharge plasma on the surface, structural, thermal and moisture sorption properties of edible zein films have been examined. Plasma treatment increased the surface roughness and equillibrium moisture content of the zein film in a direct relationship with the applied voltage level. No significant difference in the thermal stability of the zein film is also observed after plasma treatment. Dielectric barrier discharge plasma treatments of zein film lead to a change in the protein conformation which is confirmed by X-ray …

Plasma Processes And Polymers Special Issue On: Plasma And Cancer, Mounir Laroussi, Michael Keidar

Electrical & Computer Engineering Faculty Publications

During the last two decades, research efforts on the application of low temperature plasmas in biology and medicine have positioned nonequilibrium lowtemperature plasmas as a technology that has the potential of revolutionizing healthcare.[1,2] Low temperature plasmas can be applied in direct contact with living tissues to inactivate bacteria,[3] to disinfect wounds and accelerate wound healing,[4] and to induce damage in some cancer cells.[5–11]

The Effect Of Microscopic Texture On The Direct Plasma Surface Passivation Of Si Solar Cells, S Mehrabian, S Xu, A A. Qaemi, B Shokri, C Chan, K Ostrikov

Australian Institute for Innovative Materials - Papers

Textured silicon surfaces are widely used in manufacturing of solar cells due to increasing the light absorption probability and also the antireflection properties. However, these Si surfaces have a high density of surface defects that need to be passivated. In this study, the effect of the microscopic surface texture on the plasma surface passivation of solar cells is investigated. The movement of 105Hþ ions in the texture-modified plasma sheath is studied by Monte Carlo numerical simulation. The hydrogen ions are driven by the combined electric field of the plasma sheath and the textured surface. The ion dynamics is simulated, and …

Plasmon-Mediated Magneto-Optical Transparency, Vladimir Belotelov, L. E. Kreilkamp, Ilya Akimov, A Kalish, D Bykov, S Kasture, V Yallapragada, A Gopal, A M Grishin, S I Khartsev, Mohammad Nur E Alam, Mikhail Vasiliev, L Doskolovich, D Yakovlev, Kamal Alameh, A K Zvezdin, M Bayer

Research outputs 2013

Magnetic field control of light is among the most intriguing methods for modulation of light intensity and polarization on sub-nanosecond timescales. The implementation in nanostructured hybrid materials provides a remarkable increase of magneto-optical effects. However, so far only the enhancement of already known effects has been demonstrated in such materials. Here we postulate a novel magneto-optical phenomenon that originates solely from suitably designed nanostructured metal-dielectric material, the so-called magneto-plasmonic crystal. In this material, an incident light excites coupled plasmonic oscillations and a waveguide mode. An in-plane magnetic field allows excitation of an orthogonally polarized waveguide mode that modifies optical spectrum …

Ignition Of A Large Volume Plasma With A Plasma Jet, M. Laroussi, M. A. Akman

Electrical & Computer Engineering Faculty Publications

Here we report on a method to generate a long plasma plume and to ignite a large volume plasma by means of the jet. The plasma plume is generated by our tube reactor and then introduced into a chamber where the pressure is controlled. We discovered there are three operating phases:Aphasewhere the plume length remains approximately constant, followed by a second phase where the jet increases in length as the pressure decreases. Then at pressures below 70 Torr a mode transition occurs where the plume length decreases and the plasma expands until the entire chamber is filled.

Plasma-Enhanced Chemical Vapour Deposition On Particles In An Atmospheric Circulating Fluidized Bed, J. Ruud Van Ommen, Elena Abadjieva, Yves L.M. Creyghton

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

Plasma-enhanced chemical vapour deposition is an attractive technqiue to provide particles with a thin film. Applying a cold plasma enables us to work with temperature-sensitive materials. Using a CFB with an incorporated volume dielectric barrier discharge reactor we coated 20-30 m CuO particles with a thin SiOx layer.

Plasma Actuator, Jamey D. Jacob

Mechanical Engineering Faculty Patents

An actuator including a first and second conductor on a dielectric, wherein application of a voltage to the first conductor creates a plasma, thereby modifying a fluid flow in communication with the actuator. Related systems and methods are also provided.