WorldWideScience

Sample records for open plasma devices

  1. Optical plasma microelectronic devices

    CERN Document Server

    Forati, Ebrahim; Dill, Thyler; Sievenpiper, Dan

    2015-01-01

    The semiconductor channel in conventional microelectronic devices was successfully replaced with an optically triggered gas plasma channel. The combination of DC and laser-induced gas ionizations controls the conductivity of the channel, enabling us to realize different electronic devices such as transistors, switches, modulators, etc. A special micro-scale metasurface was used to enhance the laser-gas interaction, as well as combining it with DC ionization properly. Optical plasma devices benefit form the advantages of plasma/vacuum electronic devices while preserving most of the integrablity of semiconductor based devices.

  2. Modelling of new generation plasma optical devices

    Directory of Open Access Journals (Sweden)

    Litovko Irina V.

    2016-06-01

    Full Text Available The paper presents new generation plasma optical devices based on the electrostatic plasma lens configuration that opens a novel attractive possibility for effective high-tech practical applications. Original approaches to use of plasma accelerators with closed electron drift and open walls for the creation of a cost-effective low-maintenance plasma lens with positive space charge and possible application for low-cost, low-energy rocket engine are described. The preliminary experimental, theoretical and simulation results are presented. It is noted that the presented plasma devices are attractive for many different applications in the state-of-the-art vacuum-plasma processing.

  3. Plasma detachment in linear devices

    Science.gov (United States)

    Ohno, N.

    2017-03-01

    Plasma detachment research in linear devices, sometimes called divertor plasma simulators, is reviewed. Pioneering works exploring the concept of plasma detachment were conducted in linear devices. Linear devices have contributed greatly to the basic understanding of plasma detachment such as volume plasma recombination processes, detached plasma structure associated with particle and energy transport, and other related issues including enhancement of convective plasma transport, dynamic response of plasma detachment, plasma flow reversal, and magnetic field effect. The importance of plasma detachment research using linear devices will be highlighted aimed at the design of future DEMO.

  4. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min Suk

    2017-02-16

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

  5. Open-source hardware for medical devices.

    Science.gov (United States)

    Niezen, Gerrit; Eslambolchilar, Parisa; Thimbleby, Harold

    2016-04-01

    Open-source hardware is hardware whose design is made publicly available so anyone can study, modify, distribute, make and sell the design or the hardware based on that design. Some open-source hardware projects can potentially be used as active medical devices. The open-source approach offers a unique combination of advantages, including reducing costs and faster innovation. This article compares 10 of open-source healthcare projects in terms of how easy it is to obtain the required components and build the device.

  6. Alpha Channeling in Open-System Magnetic Devices

    Energy Technology Data Exchange (ETDEWEB)

    Fisch, Nathaniel [Princeton Univ., NJ (United States)

    2016-06-19

    The Grant DE-SC0000736, Alpha Channeling in Open-System Magnetic Devices, is a continuation of the Grant DE-FG02-06ER54851, Alpha Channeling in Mirror Machines. In publications funded by DE-SC0000736, the grant DE-FG02-06ER54851 was actually credited. The key results obtained under Grant DE-SC0000736, Alpha Channeling in Open-System Magnetic Devices, appear in a series of publications. The earlier effort under DE-FG02- 06ER54851 was the subject of a previous Final Report. The theme of this later effort has been unusual confinement effects, or de-confinement effects, in open-field magnetic confinement devices. First, the possibilities in losing axisymmetry were explored. Then a number of issues in rotating plasma were addressed. Most importantly, a spinoff application to plasma separations was recognized, which also resulted in a provisional patent application. (That provisional patent application, however, was not pursued further.) Alpha channeling entails injecting waves into magnetically confined plasma to release energy from one particular ion while ejecting that ion. The ejection of the ion is actually a concomitant effect in releasing energy from the ion to the wave. In rotating plasma, there is the opportunity to store the energy in a radial electric field rather than in waves. In other words, the ejected alpha particle loses its energy to the radial potential, which in turn produces plasma rotation. This is a very useful effect, since producing radial electric fields by other means are technologically more difficult. In fact, one can heat ions, and then eject them, to produce the desired radial field. In each case, there is a separation effect of different ions, which generalizes the original alpha-channeling concept of separating alpha ash from hydrogen. In a further generalization of the separation concept, a double-well filter represents a new way to produce high-throughput separations of ions, potentially useful for nuclear waste remediation.

  7. Investigation of opening switch mechanisms based on chemically reactive plasmas

    Science.gov (United States)

    Lapatovich, W. P.; Piejak, R. B.; Proud, J. M.

    1985-11-01

    An investigation of discharge-induced chemical reactions resulting in high-density product vapors containing strongly attaching gases has been conducted to evaluate the feasibility and potential of such reactions in rapid opening plasma switches. This new concept of employing such reactions to limit and/or interrupt large currents on a microsecond time scale was studied in two element (electrodeless and electroded) devices and in three element (electroded) devices. Bimolecular and unimolecular reactions were considered. The plasma reaction between AlCl sub 3 and SiO sub 2 was studied. The electrical properties of one of the reaction products (SiCl sub 4) is reported.

  8. Open source OCR framework using mobile devices

    Science.gov (United States)

    Zhou, Steven Zhiying; Gilani, Syed Omer; Winkler, Stefan

    2008-02-01

    Mobile phones have evolved from passive one-to-one communication device to powerful handheld computing device. Today most new mobile phones are capable of capturing images, recording video, and browsing internet and do much more. Exciting new social applications are emerging on mobile landscape, like, business card readers, sing detectors and translators. These applications help people quickly gather the information in digital format and interpret them without the need of carrying laptops or tablet PCs. However with all these advancements we find very few open source software available for mobile phones. For instance currently there are many open source OCR engines for desktop platform but, to our knowledge, none are available on mobile platform. Keeping this in perspective we propose a complete text detection and recognition system with speech synthesis ability, using existing desktop technology. In this work we developed a complete OCR framework with subsystems from open source desktop community. This includes a popular open source OCR engine named Tesseract for text detection & recognition and Flite speech synthesis module, for adding text-to-speech ability.

  9. Operational status of the Magnum-PSI linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Scholten, John, E-mail: j.scholten@differ.nl; Zeijlmans van Emmichoven, P.A.; Eck, H.J.N. van; Smeets, P.H.M.; De Temmerman, G.C.; Brons, S.; Berg, M.A. van den; Meiden, H.J. van der; Pol, M.J. van de; Graswinckel, M.F.; Groen, P.W.C.; Poelman, A.J.; Genuit, J.W.

    2013-10-15

    Highlights: • High heat flux, high density plasmas in a highly accessible linear plasma device. • Plasma exposure of targets of different sizes under selectable plasma beam angles. • Dedicated plasma and surface diagnostics. • Differential vacuum pumping system. -- Abstract: The construction phase of the linear plasma generator Magnum-PSI at the FOM institute DIFFER has been completed and the facility has been officially opened in March 2012. The scientific program to gain more insight in the plasma–wall interactions relevant for ITER and future fusion reactors has started. In Magnum-PSI, targets of a wide range of materials and shapes can be exposed to high particle, high heat flux plasmas (>10{sup 24} ions m{sup −2} s{sup −1}; >10 MW/m{sup 2}). For magnetization of the plasma, oil-cooled electromagnets are temporarily installed to enable pulsed operation until the device is upgraded with a superconducting magnet. The magnets generate a field of up to 1.9 T close to the plasma source for a duration of 6 s. Longer exposure times are available for lower field settings. Plasma characterizations were done with a variety of gases (H, D, He, Ne and Ar) to determine the machine performance and prepare for subsequent scientific experiments. Thomson scattering and optical emission spectroscopy were used to determine the plasma parameters while infrared thermography and target calorimetry were used to determine the power loads to the surface. This paper reports on the status of Magnum-PSI and its diagnostic systems. In addition, an overview of the plasma parameters that can be achieved in the present state will be given.

  10. Modeling of plasma devices for pulsed power

    Science.gov (United States)

    Kunc, Joseph A.; Gundersen, Martin A.

    1984-07-01

    This letter considers quantitative models of microscopic processes in plasmas formed in gas phase devices for pulsed power. Although models have been developed for devices such as lasers, there are others, such as switches, where these processes have been treated only phenomenologically. Further, transport data must be adjusted to include the effects of high electron density. It is shown that it is necessary to use a microscopic model to correctly describe the device behavior. Examples presented include the effect of Coulomb collisions on conductivity in various gases, and the ionization processes in a hydrogen thyratron.

  11. Plasma surface interactions in controlled fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Ghendrih, Ph.; Becoulet, M.; Costanzo, L. [and others

    2000-07-01

    This report brings together all the contributions of EURATOM/CEA association to the 14. international conference on plasma surface interactions in controlled fusion devices. 24 papers are presented and they deal mainly with the ergodic divertor and the first wall of Tore-supra tokamak.

  12. Maestro: Data Orchestation and Tuning for OpenCL Devices

    Energy Technology Data Exchange (ETDEWEB)

    Spafford, Kyle L [ORNL; Meredith, Jeremy S [ORNL; Vetter, Jeffrey S [ORNL

    2010-01-01

    Abstract. As heterogeneous computing platforms become more prevalent, the programmer must account for complex memory hierarchies in addition to the diculties of parallel programming. OpenCL is an open standard for parallel computing that helps alleviate this diculty by providing a portable set of abstractions for device memory hierarchies. However, OpenCL requires that the programmer explicitly controls data transfer and device synchronization, two tedious and error-prone tasks. This paper introduces Maestro, an open source library for data orchestration on OpenCL devices. Maestro provides automatic data transfer, task decomposition across multiple devices, and autotuning of dynamic execution parameters for some types of problems.

  13. Plasma opening switch with extrinsic magnetic field

    CERN Document Server

    Dolgachev, G; Maslennikov, D

    2001-01-01

    Summary form only given, as follows. We have demonstrated in series of experiments that plasma opening switch (POS) switching voltage (UPOS) is defined by energy density (w) deposited in the POS plasma. If we then consider a plasma erosion mainly responsible for the effect of POS switching (the erosion effect could be described by Hall or Child-Langmuir models) the energy density (w) could be measured as a function of a system "macro-parameter" such as the initial charging voltage of the capacity storage system (the Marx pulsed voltage generator) UMarx. The POS voltage in this case could be given by UPOS"aw=aUMarx4/7, where a is a constant. This report demonstrates that for the high-impedance POS which has limited charge density transferred through the POS plasma a"2.5 (MV3/7) with no external magnetic field applied. The use of the extrinsic magnetic field allows to increase a up to 3.6 (MV3/7) and to achieve higher voltages at the opening phase - UPOS=3.6UMarx4/7. To verify this approach set of experimental ...

  14. Understanding of Edge Plasmas in Magnetic Fusion Energy Devices

    Energy Technology Data Exchange (ETDEWEB)

    Rognlien, T

    2004-11-01

    A limited overview is given of the theoretical understanding of edge plasmas in fusion devices. This plasma occupies the thin region between the hot core plasma and material walls in magnetically confinement configurations. The region is often formed by a change in magnetic topology from close magnetic field lines (i.e., the core region) and open field lines that contact material surfaces (i.e., the scrape-off layer [SOL]), with the most common example being magnetically diverted tokamaks. The physics of this region is determined by the interaction of plasma with neutral gas in the presence of plasma turbulence, with impurity radiation being an important component. Recent advances in modeling strong, intermittent micro-turbulent edge-plasma transport is given, and the closely coupled self-consistent evolution of the edge-plasma profiles in tokamaks. In addition, selected new results are given for the characterization of edge-plasmas behavior in the areas of edge-pedestal relaxation and SOL transport via Edge-Localize Modes (ELMs), impurity formation including dust, and magnetic field-line stochasticity in tokamaks.

  15. Pulsed Plasma Lubrication Device and Method

    Science.gov (United States)

    Hofer, Richard R. (Inventor); Bickler, Donald B. (Inventor); D'Agostino, Saverio A. (Inventor)

    2016-01-01

    Disclosed herein is a lubrication device comprising a solid lubricant disposed between and in contact with a first electrode and a second electrode dimensioned and arranged such that application of an electric potential between the first electrode and the second electrode sufficient to produce an electric arc between the first electrode and the second electrode to produce a plasma in an ambient atmosphere at an ambient pressure which vaporizes at least a portion of the solid lubricant to produce a vapor stream comprising the solid lubricant. Methods to lubricate a surface utilizing the lubrication device in-situ are also disclosed.

  16. Open Mobile API: Accessing the UICC on Android Devices

    OpenAIRE

    Roland, Michael; Hölzl, Michael

    2016-01-01

    This report gives an overview of secure element integration into Android devices. It focuses on the Open Mobile API as an open interface to access secure elements from Android applications. The overall architecture of the Open Mobile API is described and current Android devices are analyzed with regard to the availability of this API. Moreover, this report summarizes our efforts of reverse engineering the stock ROM of a Samsung Galaxy S3 in order to analyze the integration of the Open Mobile ...

  17. Launched electrons in plasma opening switches

    Science.gov (United States)

    Mendel, C. W., Jr.; Rochau, G. E.; Sweeney, M. A.; McDaniel, D. H.; Quintenz, J. P.; Savage, M. E.; Lindman, E. L.; Kindel, J. M.

    Plasma opening switches have provided a means to improve the characteristics of super-power pulse generators. Recent advances involving plasma control with fast and slow magnetic fields have made these switches more versatile, allowing for improved switch uniformity, triggering, and opening current levels that are set by the level of auxiliary fields. Such switches necessarily involve breaks in the translational symmetry of the transmission line geometry and therefore affect the electron flow characteristics of the line. These symmetry breaks are the result of high electric field regions caused by plasma conductors remaining in the transmission line, ion beams crossing the line, or auxilliary magnetic field regions. Symmetry breaks cause the canonical momentum of the electrons to change, thereby moving them away from the cathode. Additional electrons are pulled from the cathode into the magnetically insulated flow, resulting in an excess of electron flow over that expected for the voltage and line current downstream of the switch. These electrons are called launched electrons. Unless they are recaptured at the cathode or else are fed into the load and used beneficially, they cause a large power loss downstream. Examples are shown of SuperMite and PBFA II data showing these losses, the tools used to study them are explained, and the mechanisms employed to mitigate the problem are discussed. The losses will be reduced primarily by reducing the amount of launched electron flow.

  18. Space as an open plasma laboratory

    Science.gov (United States)

    Papadopoulos, Konstantinos

    2011-10-01

    Ionospheric heaters supplemented by ground and space based diagnostic instruments have for a long time being used to conduct plasma physics, geophysical and radio science investigations. The recently completed HF transmitter associated with the High Frequency Active Ionospheric Research Program (HAARP), far exceeds the capabilities of previous ionospheric heaters and allows for new frontier research in plasma physics, geophysics and radio science. The transmitter radiates 3.6 MW of HF power in the 2.8-10.0 MHz frequency range. The beam-width varies from 15-5 degrees, corresponding to 20-30 dB gain and resulting in Effective Radiating Power (ERP) between.36-4.0 GW. The antenna can point to any direction in a cone of 30 degrees from the vertical, with a reposition time of 15 degrees in 15 microseconds resulting in super-luminous scanning speeds. The transmitter can synthesize essentially any desired waveform in linear and circular polarization. We present a number of HAARP experiments that used space as an open plasma laboratory. The experiments cover the areas of (i) Artificial ULF/ELF/VLF generation and injection in the magnetosphere (ii) Studies of wave-particle interactions in the magnetosphere (iii) Langmuir turbulence, parametric instabilities, electron acceleration and optical emissions (iv) Artificial ionization. Ionospheric heaters supplemented by ground and space based diagnostic instruments have for a long time being used to conduct plasma physics, geophysical and radio science investigations. The recently completed HF transmitter associated with the High Frequency Active Ionospheric Research Program (HAARP), far exceeds the capabilities of previous ionospheric heaters and allows for new frontier research in plasma physics, geophysics and radio science. The transmitter radiates 3.6 MW of HF power in the 2.8-10.0 MHz frequency range. The beam-width varies from 15-5 degrees, corresponding to 20-30 dB gain and resulting in Effective Radiating Power (ERP

  19. Variation of plasma parameters in a modified mode of plasma production in a double plasma device

    Indian Academy of Sciences (India)

    A Phukan; M K Mishra; B K Saikia; M Chakraborty

    2010-03-01

    A modified mode of plasma production in a double plasma device is presented and plasma parameters are controlled in this configuration. Here plasma is produced by applying a discharge voltage between the hot filaments in the source (cathode) and the target magnetic cage (anode) of the device. In this configuration, the hot electron emitting filaments are present only in the source and the magnetic cage of this is kept at a negative bias such that due to the repulsion of the cage bias, the primary electrons can go to the grounded target and produce plasma there. The plasma parameters can be controlled by varying the voltages applied to the source magnetic cage and the separation grid of the device.

  20. Plasma flow in peripheral region of detached plasma in linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y., E-mail: hayashi-yuki13@ees.nagoya-u.ac.jp; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Kajita, S. [EcoTopia Science Institute, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Tanaka, H. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

    2016-01-15

    A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.

  1. Thermovoltaic semiconductor device including a plasma filter

    Science.gov (United States)

    Baldasaro, Paul F.

    1999-01-01

    A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.

  2. plasmaFoam: An OpenFOAM framework for computational plasma physics and chemistry

    Science.gov (United States)

    Venkattraman, Ayyaswamy; Verma, Abhishek Kumar

    2016-09-01

    As emphasized in the 2012 Roadmap for low temperature plasmas (LTP), scientific computing has emerged as an essential tool for the investigation and prediction of the fundamental physical and chemical processes associated with these systems. While several in-house and commercial codes exist, with each having its own advantages and disadvantages, a common framework that can be developed by researchers from all over the world will likely accelerate the impact of computational studies on advances in low-temperature plasma physics and chemistry. In this regard, we present a finite volume computational toolbox to perform high-fidelity simulations of LTP systems. This framework, primarily based on the OpenFOAM solver suite, allows us to enhance our understanding of multiscale plasma phenomenon by performing massively parallel, three-dimensional simulations on unstructured meshes using well-established high performance computing tools that are widely used in the computational fluid dynamics community. In this talk, we will present preliminary results obtained using the OpenFOAM-based solver suite with benchmark three-dimensional simulations of microplasma devices including both dielectric and plasma regions. We will also discuss the future outlook for the solver suite.

  3. Autonomous Method and System for Minimizing the Magnitude of Plasma Discharge Current Oscillations in a Hall Effect Plasma Device

    Science.gov (United States)

    Hruby, Vladimir (Inventor); Demmons, Nathaniel (Inventor); Ehrbar, Eric (Inventor); Pote, Bruce (Inventor); Rosenblad, Nathan (Inventor)

    2014-01-01

    An autonomous method for minimizing the magnitude of plasma discharge current oscillations in a Hall effect plasma device includes iteratively measuring plasma discharge current oscillations of the plasma device and iteratively adjusting the magnet current delivered to the plasma device in response to measured plasma discharge current oscillations to reduce the magnitude of the plasma discharge current oscillations.

  4. Open active cloaking and illusion devices for the Laplace equation

    Science.gov (United States)

    Ma, Qian; Yang, Fan; Jin, Tian Yu; Lei Mei, Zhong; Cui, Tie Jun

    2016-04-01

    We propose open active cloaking and illusion devices for the Laplace equation. Compared with the closed configurations of active cloaking and illusion devices, we focus on improving the distribution schemes for the controlled sources, which do not have to surround the protected object strictly. Instead, the controlled sources can be placed in several small discrete clusters, and produce the desired voltages along the controlled boundary, to actively hide or disguise the protected object. Numerical simulations are performed with satisfactory results, which are further validated by experimental measurements. The open cloaking and illusion devices have many advantages over the closed configurations in various potential applications.

  5. An OpenMP Programming Environment on Mobile Devices

    Directory of Open Access Journals (Sweden)

    Tyng-Yeu Liang

    2016-01-01

    Full Text Available Recently, the computational speed and battery capability of mobile devices were greatly promoted. With an enormous number of APPs, users can do many things in mobile devices as well as in computers. Consequently, more and more scientific researchers are encouraged to move their working environment from computers to mobile devices for increasing their work efficiency because they can analyze data and make decisions on their mobile devices anytime and anywhere. Accordingly, we propose a mobile OpenMP programming environment called MOMP in this paper. Using this APP, users can directly write, compile, and execute OpenMP programs on their Android-based mobile devices to exploit embedded CPU and GPU for resolving their problems without network connection. Because of source compatibility, MOMP makes users easily port their OpenMP programs from computers to mobile devices without any modification. Moreover, MOMP provides users with an easy interface to choose CPU or GPU for executing different parallel regions in the same program based on the properties of parallel regions. Therefore, MOMP can effectively reduce the programming complexity of heterogeneous computing in mobile devices and exploit the computational power of mobile devices for the performance of user applications.

  6. Slot-Antenna/Permanent-Magnet Device for Generating Plasma

    Science.gov (United States)

    Foster, John E.

    2007-01-01

    A device that includes a rectangular-waveguide/slot-antenna structure and permanent magnets has been devised as a means of generating a substantially uniform plasma over a relatively large area, using relatively low input power and a low gas flow rate. The device utilizes electron cyclotron resonance (ECR) excited by microwave power to efficiently generate plasma in a manner that is completely electrodeless in the sense that, in principle, there is no electrical contact between the plasma and the antenna. Plasmas generated by devices like this one are suitable for use as sources of ions and/or electrons for diverse material-processing applications (e.g., etching or deposition) and for ion thrusters. The absence of plasma/electrode contact essentially prevents plasma-induced erosion of the antenna, thereby also helping to minimize contamination of the plasma and of objects exposed to the plasma. Consequently, the operational lifetime of the rectangular-waveguide/ slot-antenna structure is long and the lifetime of the plasma source is limited by the lifetime of the associated charged-particle-extraction grid (if used) or the lifetime of the microwave power source. The device includes a series of matched radiating slot pairs that are distributed along the length of a plasma-source discharge chamber (see figure). This arrangement enables the production of plasma in a distributed fashion, thereby giving rise to a uniform plasma profile. A uniform plasma profile is necessary for uniformity in any electron- or ion-extraction electrostatic optics. The slotted configuration of the waveguide/ antenna structure makes the device scalable to larger areas and higher powers. All that is needed for scaling up is the attachment of additional matched radiating slots along the length of the discharge chamber. If it is desired to make the power per slot remain constant in scaling up, then the input microwave power must be increased accordingly. Unlike in prior ECR microwave plasma

  7. Arc plasma devices: Evolving mechanical design from numerical simulation

    Indian Academy of Sciences (India)

    S Ghorui; A K Das

    2013-04-01

    Wide ranges of technological applications involve arc plasma devices as the primary plasma source for processing work. Recent findings exhibit the existence of appreciable thermal non-equilibrium in these so-called thermal plasma devices. Commercially available magnetohydrodynamic codes are not capable of handling such systems due to unavailability of non-equilibrium thermodynamic and transport property data and self-consistent models. A recipe for obtaining mechanical design of arc plasma devices from numerical simulation incorporating two-temperature thermal non-equilibrium model is presented in this article with reference to the plasma of the mixture of molecular gases like nitrogen and oxygen. Such systems are technologically important as they correspond to the plasma devices operating with air, oxygen plasma torches in cutting industries and plasma devices using nitrogen as shielding gas. Temperature field, associated fluid dynamics and electrical characteristics of a plasma torch are computed in a systematic manner to evaluate the performance of a conceived design using a two-fluid CFD model coupled with a two-temperature thermodynamic and transport property code. Important effects of different nozzle designs and plasma gases obtained from the formalism are discussed. Non-equilibrium thermo-dynamic properties are computed using modified two-temperature Saha equations and transport properties are computed using standard Chapman–Enskog approach.

  8. Plasma cell treatment device Plasma-on-Chip: Monitoring plasma-generated reactive species in microwells

    Science.gov (United States)

    Oh, Jun-Seok; Kojima, Shinya; Sasaki, Minoru; Hatta, Akimitsu; Kumagai, Shinya

    2017-01-01

    We have developed a plasma cell treatment device called Plasma-on-Chip that enables the real-time monitoring of a single cell culture during plasma treatment. The device consists of three parts: 1) microwells for cell culture, 2) a microplasma device for generating reactive oxygen and nitrogen species (RONS) for use in cell treatment, and 3) through-holes (microchannels) that connect each microwell with the microplasma region for RONS delivery. Here, we analysed the delivery of the RONS to the liquid culture medium stored in the microwells. We developed a simple experimental set-up using a microdevice and applied in situ ultraviolet absorption spectroscopy with high sensitivity for detecting RONS in liquid. The plasma-generated RONS were delivered into the liquid culture medium via the through-holes fabricated into the microdevice. The RONS concentrations were on the order of 10–100 μM depending on the size of the through-holes. In contrast, we found that the amount of dissolved oxygen was almost constant. To investigate the process of RONS generation, we numerically analysed the gas flow in the through-holes. We suggest that the circulating gas flow in the through-holes promotes the interaction between the plasma (ionised gas) and the liquid, resulting in enhanced RONS concentrations. PMID:28176800

  9. An open source device for operant licking in rats.

    Science.gov (United States)

    Longley, Matthew; Willis, Ethan L; Tay, Cindy X; Chen, Hao

    2017-01-01

    We created an easy-to-use device for operant licking experiments and another device that records environmental variables. Both devices use the Raspberry Pi computer to obtain data from multiple input devices (e.g., radio frequency identification tag readers, touch and motion sensors, environmental sensors) and activate output devices (e.g., LED lights, syringe pumps) as needed. Data gathered from these devices are stored locally on the computer but can be automatically transferred to a remote server via a wireless network. We tested the operant device by training rats to obtain either sucrose or water under the control of a fixed ratio, a variable ratio, or a progressive ratio reinforcement schedule. The lick data demonstrated that the device has sufficient precision and time resolution to record the fast licking behavior of rats. Data from the environment monitoring device also showed reliable measurements. By providing the source code and 3D design under an open source license, we believe these examples will stimulate innovation in behavioral studies. The source code can be found at http://github.com/chen42/openbehavior.

  10. An open source device for operant licking in rats

    Directory of Open Access Journals (Sweden)

    Matthew Longley

    2017-02-01

    Full Text Available We created an easy-to-use device for operant licking experiments and another device that records environmental variables. Both devices use the Raspberry Pi computer to obtain data from multiple input devices (e.g., radio frequency identification tag readers, touch and motion sensors, environmental sensors and activate output devices (e.g., LED lights, syringe pumps as needed. Data gathered from these devices are stored locally on the computer but can be automatically transferred to a remote server via a wireless network. We tested the operant device by training rats to obtain either sucrose or water under the control of a fixed ratio, a variable ratio, or a progressive ratio reinforcement schedule. The lick data demonstrated that the device has sufficient precision and time resolution to record the fast licking behavior of rats. Data from the environment monitoring device also showed reliable measurements. By providing the source code and 3D design under an open source license, we believe these examples will stimulate innovation in behavioral studies. The source code can be found at http://github.com/chen42/openbehavior.

  11. An open source device for operant licking in rats

    Science.gov (United States)

    Longley, Matthew; Willis, Ethan L.; Tay, Cindy X.

    2017-01-01

    We created an easy-to-use device for operant licking experiments and another device that records environmental variables. Both devices use the Raspberry Pi computer to obtain data from multiple input devices (e.g., radio frequency identification tag readers, touch and motion sensors, environmental sensors) and activate output devices (e.g., LED lights, syringe pumps) as needed. Data gathered from these devices are stored locally on the computer but can be automatically transferred to a remote server via a wireless network. We tested the operant device by training rats to obtain either sucrose or water under the control of a fixed ratio, a variable ratio, or a progressive ratio reinforcement schedule. The lick data demonstrated that the device has sufficient precision and time resolution to record the fast licking behavior of rats. Data from the environment monitoring device also showed reliable measurements. By providing the source code and 3D design under an open source license, we believe these examples will stimulate innovation in behavioral studies. The source code can be found at http://github.com/chen42/openbehavior. PMID:28229020

  12. In-liquid plasma devices and methods of use thereof

    KAUST Repository

    Cha, Min Suk

    2017-08-10

    Devices and methods for generating a plasma in a liquid are provided. A low- dielectric material can be placed in contact with the liquid to form an interface a distance from an anode. A voltage can be applied across the anode and a cathode submerged in the liquid to produce the plasma. A variety of devices are provided, including for continuous operation. The devices and methods can be used to generate a plasma in a variety of liquids, for example for water treatment, hydrocarbon reformation, or synthesis of nanomaterial.

  13. Plasma opening switch studies of an applied Bz ion diode

    Science.gov (United States)

    Struckman, C. K.; Kusse, B. R.; Meyerhofer, D. D.; Rondeau, G.

    1989-05-01

    The light ion accelerator (1.5 MV, 4 ohms) at Cornell University is being used to study the characteristics of an applied Bz, or 'barrel', diode. The results of a series of experiments utilizing a plasma opening switch are reported. With a magnetically insulated ion diode load, the peak diode voltage increase from 1.5 to 1.8 MV and the ion power increased from 50 to 80 GW when a plasma opening switch was used.

  14. Launching of Microwaves into a Dense Plasma in Open Confinement Systems

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, A. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

    2001-02-15

    A study is made of the propagation of microwave beams in a plasma and their passage through the critical surface. It is shown that, in order for microwaves to penetrate deeply into a dense plasma, it is necessary to launch them through a magnetic mirror at a slight angle to the device axis. The characteristic features of ray trajectories are analyzed both ahead of and behind the critical surface. In a dense plasma behind the critical surface, microwaves tend to run out of the axial region toward the plasma periphery. This tendency may be unfavorable for heating plasmas whose radial density profiles are strongly peaked about the system axis. The problems under analysis are particularly important for assessing the prospects for ECR heating of dense plasmas in open confinement systems.

  15. Analysis of Power Model for Linear Plasma Device

    Science.gov (United States)

    Zhang, Weiwei; Deng, Baiquan; Zuo, Haoyi; Zheng, Xianjun; Cao, Xiaogang; Xue, Xiaoyan; Ou, Wei; Cao, Zhi; Gou, Fujun

    2016-08-01

    A single cathode linear plasma device has been designed and constructed to investigate the interactions between plasma and materials at the Sichuan University. In order to further investigate the Ohmic power of the device, the output heat load on the specimen and electric potential difference (between cathode and anode) have been tested under different discharge currents. This special power distribution in the radial direction of the plasma discharge channel has also been discussed and described by some improved integral equations in this paper; it can be further simplified as P ∝ α-2 in one-parameter. Besides, we have measured the power loss of the channel under different discharge currents by the calorimetric method, calculated the effective power of the device and evaluated the performances of the plasma device through the power efficiency analysis. supported by International Thermonuclear Experimental Reactor (ITER) Program (No. 2013GB114003) and National Natural Science Foundation of China (Nos. 11275135 and 11475122)

  16. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2013-10-01

    sensitive surfaces. In this paper, the consumed power for plasma generation (plasma power) has been estimated from voltage-current waveform analysis in... consumed power for plasma generation is calculated by integrating the product of the discharge voltage and current over one cycle; according to the...Faculty Symposium: Course Design for the Millennial Student, Texas A&M University – Corpus Christi, 2011. (Showcased by the Center for Faculty

  17. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2015-12-01

    research associates. The PI and the research team have published over 10 journal articles and over 50 conference proceedings and over 50 symposiums...reflections. Optical interference filters with center wavelength at 5322 or 632.82 nm are used in front of the ICCD to suppress the plasma self- luminescence ...wavelength at 532 ± 2 nm was used in front of the ICCD to suppress the plasma jet self- luminescence . The shadow of the laser induced plasma falls onto

  18. Observation of plasma motion in a coaxial plasma opening switch with a chordal laser interferometer

    Energy Technology Data Exchange (ETDEWEB)

    Teramoto, Y.; Urakami, H.; Akiyama, H. [Kumamoto Univ., Graduate School of Science and Technology, Kumamoto (Japan); Kohno, S. [Ariake National College of Technology, Dept. of Electrical Engineering, Fukuoka (Japan); Katsuki, S. [Kumamoto Univ., Dept. of Electrical and Computer Engineering, Kumamoto (Japan)

    2002-06-01

    Electron densities in a coaxial plasma opening switch were measured at many lines-of-slight. In the present experiment, electron density was measured by a He-Ne laser interferometer with chordal lines-of sight. In order to observe the motion of the POS plasma, the electron density contours during the conduction, opening and post-opening phases were drawn by combining the results of interferometer experiments. The radial and axial motion of POS plasma was investigated from the density contours. As conduction time progressed, the POS plasma moved toward downstream. At 800 ns, which corresponds to the time of opening in the current waveform, low-density region less than 10{sup 15} cm{sup -2} is seen at 10 mm from the cathode. After the opening was completed, the low-density gap disappeared and the shape of the corn-shape-like plasma was distorted. (author)

  19. Spectroscopic investigation of species separation in opening switch plasmas

    Science.gov (United States)

    Jackson, S. L.; Phipps, D. G.; Richardson, A. S.; Commisso, R. J.; Hinshelwood, D. D.; Murphy, D. P.; Schumer, J. W.; Weber, B. V.; Boyer, C. N.; Doron, R.; Biswas, S.; Maron, Y.

    2015-11-01

    Interactions between magnetic fields and current-carrying plasmas that lead to the separation of plasma species in multi-species plasmas are being studied in a plasma opening switch geometry. Several Marshall guns are used to inject single or multi-species plasmas between coaxial conductors connected to the output of the Naval Research Laboratory's Hawk pulsed-power generator. Following injection of the plasma, the generator is used at roughly half power to apply an electrical pulse with a peak current of 450 kA, a peak voltage of 400 kV, and a rise time of 1.2 μs. The resulting magnetic field interacts with the plasma through a combination of field penetration and magnetohydrodynamic (MHD) pushing that is not well understood but can lead to the separation of plasma species in multi-species plasmas. An ICCD-coupled spectrometer has been used in combination with magnetic probes, a ribbon-beam interferometer, and particle-in-cell (PIC) modeling to diagnose and understand conditions in the plasma from the time it is injected until the end of the conduction phase of the opening switch. This work supported by the Naval Research Laboratory Base Program and the Office of Naval Research.

  20. The HelCat dual-source plasma device.

    Science.gov (United States)

    Lynn, Alan G; Gilmore, Mark; Watts, Christopher; Herrea, Janis; Kelly, Ralph; Will, Steve; Xie, Shuangwei; Yan, Lincan; Zhang, Yue

    2009-10-01

    The HelCat (Helicon-Cathode) device has been constructed to support a broad range of basic plasma science experiments relevant to the areas of solar physics, laboratory astrophysics, plasma nonlinear dynamics, and turbulence. These research topics require a relatively large plasma source capable of operating over a broad region of parameter space with a plasma duration up to at least several milliseconds. To achieve these parameters a novel dual-source system was developed utilizing both helicon and thermionic cathode sources. Plasma parameters of n(e) approximately 0.5-50 x 10(18) m(-3) and T(e) approximately 3-12 eV allow access to a wide range of collisionalities important to the research. The HelCat device and initial characterization of plasma behavior during dual-source operation are described.

  1. Plasma enhanced vortex fluidic device manipulation of graphene oxide.

    Science.gov (United States)

    Jones, Darryl B; Chen, Xianjue; Sibley, Alexander; Quinton, Jamie S; Shearer, Cameron J; Gibson, Christopher T; Raston, Colin L

    2016-08-25

    A vortex fluid device (VFD) with non-thermal plasma liquid processing within dynamic thin films has been developed. This plasma-liquid microfluidic platform facilitates chemical processing which is demonstrated through the manipulation of the morphology and chemical character of colloidal graphene oxide in water.

  2. The HelCat basic plasma science device

    Science.gov (United States)

    Gilmore, M.; Lynn, A. G.; Desjardins, T. R.; Zhang, Y.; Watts, C.; Hsu, S. C.; Betts, S.; Kelly, R.; Schamiloglu, E.

    2015-01-01

    The Helicon-Cathode(HelCat) device is a medium-size linear experiment suitable for a wide range of basic plasma science experiments in areas such as electrostatic turbulence and transport, magnetic relaxation, and high power microwave (HPM)-plasma interactions. The HelCat device is based on dual plasma sources located at opposite ends of the 4 m long vacuum chamber - an RF helicon source at one end and a thermionic cathode at the other. Thirteen coils provide an axial magnetic field B >= 0.220 T that can be configured individually to give various magnetic configurations (e.g. solenoid, mirror, cusp). Additional plasma sources, such as a compact coaxial plasma gun, are also utilized in some experiments, and can be located either along the chamber for perpendicular (to the background magnetic field) plasma injection, or at one of the ends for parallel injection. Using the multiple plasma sources, a wide range of plasma parameters can be obtained. Here, the HelCat device is described in detail and some examples of results from previous and ongoing experiments are given. Additionally, examples of planned experiments and device modifications are also discussed.

  3. Design and Construction of a Dense Plasma Focus Device

    Science.gov (United States)

    1976-10-01

    breakdown phase ............ 6 3. Typical device waveforms ........ .................... . 11 4. Fluid models of pinch mechanisms...16 5. Ion trajectory models ........... ...................... 19 6. Fillipov-type plasma focus device ...... ................ ... 22 7...52 14a. Pulse amplifier .......... ......................... ... 56 14b. Triggering circuit for the thyratron tube and spark gap ........ 57 15

  4. New Large Diameter RF Complex Plasma Device

    Science.gov (United States)

    Meyer, John; Nosenko, Volodymyr; Thomas, Hubertus

    2016-10-01

    The Complex Plasma Research Group at the German Aerospace Center (DLR) in Oberpfaffenhofen has built a new large diameter rf plasma setup for dusty plasma experiments. The vacuum chamber is a stainless steel cylinder 0.90 m in diameter and 0.34 m in height with ports for viewing and measurement. A 0.85 m diameter plate in about the center serves as a powered electrode (13.56 MHz) with the chamber walls as the ground. It is pumped on by one of two Oerlikon turbo pumps with a pumping rate of 1100 l/s or 270 l/s. Argon gas is admitted into the chamber by an MKS mass flow meter and pumping is regulated by a butterfly valve to set pressure for experiments. A manual dropper is used to insert dust into the plasma. The dust is illuminated horizontally by a 660 nm 100 mW laser sheet and viewed from above by a Photron FASTCAM 1024 PCI camera. A vertical laser sheet of 635 nm will be used for side imaging. So far, single-layer plasma crystals of up to 15000 particles have been suspended. The particle velocity fluctuation spectra were measured and from these, the particle charge and screening length were calculated. Future experiments will explore the system-size dependence of the plasma crystal properties.

  5. Plasma parameters controlled by remote electron shower in a double plasma device

    Science.gov (United States)

    Mishra, M. K.; Phukan, A.

    2012-07-01

    The principal feature of this experiment is the electron showers consisting of three tungsten wires embedded by the plasma, which are heated up consequently emitting electrons inside the diffused plasma to control the plasma parameters in the discharge section of a double plasma device. These cold electrons emitted by the heated filament are free from maintenance of discharge which is sustained in the source section. The target plasma, where electrons are injected is produced as a result of diffusion from the source section. It is found that, plasma density and plasma potential can be effectively controlled in this way.

  6. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2014-10-01

    Gadri, J. R. Roth , T. C. Montie, K. Kelly-Wintenberg, P. P. Y. Tsai, D. J. Helfritch, P. Feldman, D. M. Sherman, F. Karakaya, Z. Y. Chen, and U. P. S...Edinburgh, Scotland : 39th IEEE International Conference on Plasma Science (ICOPS), 2012). 20. Magesh Thiyagarajan, Xavier Gonzales$, Heather...Anderson# and Megan Norfolk. Non-thermal Plasma Induction of Pre-Programmed Cell Death in Monocytic Leukemia Cells. (Edinburgh, Scotland : 39th IEEE

  7. Characterization of a microsecond-conduction-time plasma opening switch

    Science.gov (United States)

    Commisso, R. J.; Goodrich, P. J.; Grossmann, J. M.; Hinshelwood, D. D.; Ottinger, P. F.; Weber, B. V.

    1992-07-01

    This paper presents data and analyses from which emerges a physical picture of microsecond-conduction-time plasma opening switch operation. During conduction, a broad current channel penetrates axially through the plasma, moving it toward the load. Opening occurs when the current channel reaches the load end of the plasma, far from the load. During conduction, the axial line density in the interelectrode region is reduced from its value with no current conduction as a result of radial hydrodynamic forces associated with the current channel. A factor of 20 reduction is observed at opening in a small, localized region between the electrodes. When open, the switch plasma behaves like a section of magnetically insulated transmission line with an effective gap of 2 to 3 mm. Increasing the magnetic field in this gap by 50% results in an improvement of 50% in the peak load voltage and load current rise time, to 1.2 MV and 20 nsec, respectively. An erosion opening mechanism explains the inferred gap growth rate using the reduced line density at opening. Improved switch performance results when the maximum gap size is increased by using a rising load impedance.

  8. Fast Tunable Microwave Devices Using Self-driven Plasma Instabilities

    Science.gov (United States)

    Biggs, David; Cappelli, Mark

    2016-10-01

    Tunable electromagnetic devices using plasmas are of interest for various applications such as high frequency communications and analog signal processing. At microwave frequencies of tens of gigahertz, low-pressure plasmas must be employed in order to avoid high wave damping from collisions. The drawback of low-pressure plasmas is that their diffusion timescales are long, on the order of hundreds of microseconds. Other mechanisms than diffusion must be employed to achieve fast tuning capabilities of these devices. One candidate mechanism is to use a self-driven plasma instability, which may allow for fast tuning of microwave resonant cavities. In this work, a microwave resonant cavity is studied consisting of a rectangular waveguide with two conducting posts spaced along the propagation direction to form a rectangular cavity. The cavity acts as a band pass filter and transmits microwave signals around its resonant frequency. Plasma may be introduced into the cavity between the conducting posts in order to change the refractive index and thus the resonant and transmission frequency of the device. The location of the plasma and its plasma density are important parameters in determining the resonant frequency, and both parameters are capable of being tuned with plasma instabilities. This work is supported by the Air Force Office of Scientific Research.

  9. Parameters of atmospheric plasmas produced by electrosurgical devices

    Science.gov (United States)

    Keidar, Michael; Shashurin, Alexey; Canady, Jerome

    2013-10-01

    Electrosurgical systems are extensively utilized in general surgery, surgical oncology, plastic and reconstructive surgery etc. In this work we study plasma parameters created by electrosurgical system SS-200E/Argon 2 of US Medical Innovations. The maximal length of the discharge plasma column at which the discharge can be sustained was determined as function of discharge power and argon flow rate. Electrical parameters including discharge current and voltage were measured. Recently proposed Rayleigh microwave scattering method for temporally resolved density measurements of small-size atmospheric plasmas was utilized. Simultaneously, evolution of plasma column was observed using intensified charge-coupled device (ICCD) camera.

  10. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2012-10-01

    34Nonthermal Plasma Technology as a Versatile Strategy for Polymeric Biomaterials Surface Modification: A Review," Biomacromolecules, vol. 10, pp. 2351...high aspect ratio for biomedical applications with complex 3D surface geometries, capillaries and microstructure dental cavities.15-18 Atmospheric

  11. Corrosion and wear in plasma electrosurgical devices

    Science.gov (United States)

    Gaspredes, J.; Ryan, T. P.; Stalder, K. R.; Woloszko, J.

    2017-02-01

    Data were previously reported on studies of the effects of electrical discharges on the corrosion and wear of simple, single-wire test devices immersed in isotonic saline 1 . This work showed that there are a wide variety of mechanisms that can explain various aspects of electrode mass loss, even with very simple electrode geometries and operating conditions. It was found that the electrode material composition played an important role. Subsequently, our studies were expanded to include more realistic device geometries and operating conditions. This paper shows the results of studies on wear characteristics of electrodes made from a variety of highly corrosion resistant metals and alloys, including Waspaloy, Hastelloy, Inconel, Havar, Monel, and other pure metals such as Hafnium. All of these metals underwent wear testing under clinically relevant conditions. Depending on the operating conditions, multiple discrete physical and chemical effects were observed at different locations on the surface of an individual millimeter-scale device electrode. Scanning electron microscope (SEM) micrographs, Energy-dispersive X-ray spectroscopy (EDS) and area loss data will be presented for a variety of test conditions and electrode materials.

  12. Bipolar Charge Plasma Transistor: A Novel Three Terminal Device

    OpenAIRE

    Kumar, M. Jagadesh; Nadda, Kanika

    2012-01-01

    A distinctive approach for forming a lateral Bipolar Charge Plasma Transistor (BCPT) is explored using 2-D simulations. Different metal work-function electrodes are used to induce n- and p-type charge plasma layers on undoped SOI to form the emitter, base and collector regions of a lateral NPN transistor. Electrical characteristics of the proposed device are simulated and compared with that of a conventionally doped lateral bipolar junction transistor with identical dimensions. Our simulation...

  13. Plasma-filled applied B ion diode experiments using a plasma opening switch

    Science.gov (United States)

    Renk, T. J.

    1994-12-01

    In order for a plasma opening switch (POS) to open quickly and transfer power efficiently from an inductively charged vacuum transmission line to an applied B ion diode, the load impedance of the ion diode may be required to have an initial low impedance phase. A plasma-filled diode has such an impedance history. To test the effect of a plasma-filled diode on POS-diode coupling, a drifting plasma was introduced from the cathode side of an applied B ion diode operated on the LION accelerator (1.5 MV, 4 Ohm, 40 ns) at Cornell University. This plasma readily crossed the 2.1 T magnetic insulation field of the diode, and resulted in both increased diode electrical power, and an increased ability of the ion beam to remove material from a target. The plasma did not appear to have a noticeable effect on local beam steering angle.

  14. Experimental investigation of plasma flows in open trap with toroidal diverter under ECR discharge

    Energy Technology Data Exchange (ETDEWEB)

    Berezkin, A. V., E-mail: Berezkin-AV@nrcki.ru; Bragin, E. Yu., E-mail: Bragin-EY@nrcki.ru; Zhil’tsov, V. A., E-mail: Zhiltsov-VA@nrcki.ru; Kulygin, V. M., E-mail: Kulygin-VM@nrcki.ru; Yanchenkov, S. V., E-mail: Yanchenkov-SV@nrcki.ru [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    The results of experimental investigations of plasma flows from an open trap with a toroidal diverter are presented. Cold plasma is generated when introducing microwave power under conditions of electron cyclotron resonance (ECR). The radiation is introduced by a waveguide through a vacuum-tight ceramic window across the axis of the device. By means of the Langmuir probes, the spatial distributions of plasma parameters are measured. The highest density is limited to a critical value n{sub c} (∼10{sup 12} cm{sup –3}) for the generator frequency under use. It is found that the temperature and density of the plasma in the trap and in escaping flows are almost independent of the radius when the ECR zone is located near the open-trap confinement region and the density is close to n{sub c}. At the density n < n{sub c}, ring plasma structures, which collapse under the action of a low-frequency instability, are observed near the separatrix. The possible mechanisms of the occurrence of plasma structures and the nature of the plasma streams are discussed.

  15. Nonlinear magnetic field transport in opening switch plasmas

    Science.gov (United States)

    Mason, R. J.; Auer, P. L.; Sudan, R. N.; Oliver, B. V.; Seyler, C. E.; Greenly, J. B.

    1993-04-01

    The nonlinear transport of magnetic field in collisionless plasmas, as present in the plasma opening switch (POS), using the implicit multifluid simulation code anthem [J. Comput. Phys. 71, 429 (1987)] is studied. The focus is on early time behavior in the electron-magnetohydrodynamic (EMHD) limit, with the ions fixed, and the electrons streaming as a fluid under the influence of ve×B Hall forces. Through simulation, magnetic penetration and magnetic exclusion waves are characterized, due to the Hall effect in the presence of transverse density gradients, and the interaction of these Hall waves with nonlinear diffusive disturbances from electron velocity advection, (veṡ∇)ve, is studied. It is shown how these mechanisms give rise to the anode magnetic insulation layer, central diffusion, and cathode potential hill structures seen in earlier opening switch plasmas studies.

  16. Upgrading of the Magnetic Confinement Plasma Device KT-5E

    Institute of Scientific and Technical Information of China (English)

    何迎花; 余羿; 闻一之; 刘万东; 李定; 俞昌旋; 谢锦林; 李弘; 兰涛; 王昊宇

    2012-01-01

    In this article we present ideas of providing appropriate poloidal magnetic field for helimaks to help to generate toroidal magnetic plasma torus. Placing a conductive ring in the center of the cross-section to induce a suitable current, we change the helical magnetic field lines in the helimak discharge into magnetic surface. In this kind of discharge, the plasma density is greatly increased, and the corresponding density fluctuation is significantly decreased, showing a better confinement by magnetic shear. It allows more flexible and efficient experimental investigations on the toroidal magnetic confinement plasmas to be carried on in this kind of device.

  17. Study on plasma parameters and dust charging in an electrostatically plugged multicusp plasma device

    Science.gov (United States)

    Kakati, B.; Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.

    2011-06-01

    The effect of the electrostatic confinement potential on the charging of dust grains and its relationship with the plasma parameters has been studied in an electrostatically plugged multicusp dusty plasma device. Electrostatic plugging is implemented by biasing the electrically isolated magnetic multicusp channel walls. The experimental results show that voltage applied to the channel walls can be a controlling parameter for dust charging.

  18. Chaos control and taming of turbulence in plasma devices

    DEFF Research Database (Denmark)

    Klinger, T.; Schröder, C.; Block, D.;

    2001-01-01

    Chaos and turbulence are often considered as troublesome features of plasma devices. In the general framework of nonlinear dynamical systems, a number of strategies have been developed to achieve active control over complex temporal or spatio-temporal behavior. Many of these techniques apply to p...

  19. The upgraded Large Plasma Device, a machine for studying frontier basic plasma physics.

    Science.gov (United States)

    Gekelman, W; Pribyl, P; Lucky, Z; Drandell, M; Leneman, D; Maggs, J; Vincena, S; Van Compernolle, B; Tripathi, S K P; Morales, G; Carter, T A; Wang, Y; DeHaas, T

    2016-02-01

    In 1991 a manuscript describing an instrument for studying magnetized plasmas was published in this journal. The Large Plasma Device (LAPD) was upgraded in 2001 and has become a national user facility for the study of basic plasma physics. The upgrade as well as diagnostics introduced since then has significantly changed the capabilities of the device. All references to the machine still quote the original RSI paper, which at this time is not appropriate. In this work, the properties of the updated LAPD are presented. The strategy of the machine construction, the available diagnostics, the parameters available for experiments, as well as illustrations of several experiments are presented here.

  20. Numerical Experiments Providing New Insights into Plasma Focus Fusion Devices

    Directory of Open Access Journals (Sweden)

    Sing Lee

    2010-04-01

    Full Text Available Recent extensive and systematic numerical experiments have uncovered new insights into plasma focus fusion devices including the following: (1 a plasma current limitation effect, as device static inductance is reduced towards very small values; (2 scaling laws of neutron yield and soft x-ray yield as functions of storage energies and currents; (3 a global scaling law for neutron yield as a function of storage energy combining experimental and numerical data showing that scaling deterioration has probably been interpreted as neutron ‘saturation’; and (4 a fundamental cause of neutron ‘saturation’. The ground-breaking insights thus gained may completely change the directions of plasma focus fusion research.

  1. Intense ion beam generation, plasma radiation source and plasma opening switch research

    Science.gov (United States)

    Hammer, D. A.; Coleman, M. D.; Qi, N.; Similon, P. L.; Sudan, R. N.

    1989-04-01

    This report describes research on intense ion beam diodes, plasma opening switches and dense z-pinch plasma radiators. Laser induced fluorescence spectroscopy has been used to map the electrostatic potential profile in a plasma-prefilled magnetically insulated ion diode. In a simple planar diode, the measured profile is inconsistent with the electrons being confined in a sheath near the cathode by the magnetic field. Rather, the profile implies the presence of electrons throughout the accelerating gap. A theoretical model of the penetration of current and magnetic field into a plasma, and of the current-driven effective collision frequency has been developed. The snowplow action of the rising magnetic field causes a steep rise in the plasma density at the leading edge. The subsequent multistreaming of the ions caused by ion reflection at the current layer could lead to ion heating through collective effects. The two-dimensional electron flow in the plasma cathode vacuum gap is also treated. Dense z-pinch plasma radiation source experiments have been initiated on the LION accelerator using gas puff and fine wire loads. The x-pinch was found to be a more effective way to generate soft x-rays than a single wire pinch or a gas puff implosion. Plasma opening switch experiments being initiated, and plasma anode ion diode development work being terminated are also briefly described.

  2. 3. Pulsed Power Generator with Inductive-Energy Storage Using Semiconductor Opening Switch(Present and Future of Semiconductor Pulsed Power Generator : Role of Power Semiconductor Devices in Plasma Research)

    OpenAIRE

    浪平, 隆男; 佐久川, 貴志; 勝木, 淳; 秋山, 秀典; ナミヒラ, タカオ; サクガワ, タカシ; カツキ, スナオ; アキヤマ, ヒデノリ; Namihara, Takao; Sakugawa, Takashi; Katsuki, Sunao; Akiyama, Hidenori

    2005-01-01

    Pulsed power technology enables the generation of large electrical power of micro to nano second duration by compressing and releasing electrical energy. The pulsed power is utilized in a variety of applications such as large-volume non-thermal plasmas and excimer laser excitation, neither of which could be realized by conventional high-voltage and current technology. Pulsed power has been generated by capacitive energy storage (CES) systems based on the direct discharge of the capacitor. On ...

  3. Scaled Laboratory Collisionless Shock Experiments in the Large Plasma Device

    Science.gov (United States)

    Clark, S. E.; Schaeffer, D.; Everson, E.; Bondarenko, A.; Winske, D.; Constantin, C.; Niemann, C.

    2013-12-01

    Collisionless shocks in space plasmas have been investigated since the fifties and are typically studied via in-situ satellite observations, which are limited due to the large structure of collisionless shocks in space environments relative to the satellite observation platform. Scaled, repeatable experiments in the Large Plasma Device (LAPD) at UCLA provide a test bed for studying collisionless shocks in the laboratory, where questions of ion and electron heating and acceleration can be addressed and examined in detail. The experiments are performed by ablating a graphite or plastic target using the Raptor kilojoule-class laser facility at UCLA. The laser provides an on-target energy in the range of 100-500 J that drives a super-Alfvénic (MA > 1) debris plasma across a background magnetic field (200-800 G) into the ambient, magnetized LAPD plasma. Typical plasma parameters in the LAPD consist of a H+ or He+ ambient plasma with a core column (diameter > 20 cm ) density ni ~ 1013 cm-3 and electron temperature Te ~ 10 eV embedded in a larger plasma discharge (diameter ~ 80 cm) of density ni ~ 1012 cm-3 and Te ~ 5 eV. The ambient ion temperature is Ti ~ 1 eV. Experimental results from the latest collisionless shock campaign will be presented and compared with two dimensional hybrid simulations of the experiment. Fielded diagnostics include Thomson scattering, ion spectroscopy, magnetic flux probes, Langmuir probes, and microwave reflectometry.

  4. Two-fluid biasing simulations of the large plasma device

    Science.gov (United States)

    Fisher, Dustin M.; Rogers, Barrett N.

    2017-02-01

    External biasing of the Large Plasma Device (LAPD) and its impact on plasma flows and turbulence are explored for the first time in 3D simulations using the Global Braginskii Solver code. Without external biasing, the LAPD plasma spontaneously rotates in the ion diamagnetic direction. The application of a positive bias increases the plasma rotation in the simulations, which show the emergence of a coherent Kelvin Helmholtz (KH) mode outside of the cathode edge with poloidal mode number m ≃6 . Negative biasing reduces the rotation in the simulations, which exhibit KH turbulence modestly weaker than but otherwise similar to unbiased simulations. Biasing either way, but especially positively, forces the plasma potential inside the cathode edge to a spatially constant, KH-stable profile, leading to a more quiescent core plasma than the unbiased case. A moderate increase in plasma confinement and an associated steepening of the profiles are seen in the biasing runs. The simulations thus show that the application of external biasing can improve confinement while also driving a Kelvin-Helmholtz instability. Ion-neutral collisions have only a weak effect in the biased or unbiased simulations.

  5. Current and Perspective Applications of Dense Plasma Focus Devices

    Science.gov (United States)

    Gribkov, V. A.

    2008-04-01

    Dense Plasma Focus (DPF) devices' applications, which are intended to support the main-stream large-scale nuclear fusion programs (NFP) from one side (both in fundamental problems of Dense Magnetized Plasma physics and in its engineering issues) as well as elaborated for an immediate use in a number of fields from the other one, are described. In the first direction such problems as self-generated magnetic fields, implosion stability of plasma shells having a high aspect ratio, etc. are important for the Inertial Confinement Fusion (ICF) programs (e.g. as NIF), whereas different problems of current disruption phenomenon, plasma turbulence, mechanisms of generation of fast particles and neutrons in magnetized plasmas are of great interest for the large devices of the Magnetic Plasma Confinement—MPC (e.g. as ITER). In a sphere of the engineering problems of NFP it is shown that in particular the radiation material sciences have DPF as a very efficient tool for radiation tests of prospect materials and for improvement of their characteristics. In the field of broad-band current applications some results obtained in the fields of radiation material sciences, radiobiology, nuclear medicine, express Neutron Activation Analysis (including a single-shot interrogation of hidden illegal objects), dynamic non-destructive quality control, X-Ray microlithography and micromachining, and micro-radiography are presented. As the examples of the potential future applications it is proposed to use DPF as a powerful high-flux neutron source to generate very powerful pulses of neutrons in the nanosecond (ns) range of its duration for innovative experiments in nuclear physics, for the goals of radiation treatment of malignant tumors, for neutron tests of materials of the first wall, blankets and NFP device's constructions (with fluences up to 1 dpa per a year term), and ns pulses of fast electrons, neutrons and hard X-Rays for brachytherapy.

  6. Study on Performance Parameters of the Plasma Source for a Short-Conduction-Time Plasma Opening Switch

    Institute of Scientific and Technical Information of China (English)

    LUO Weixi; ZENG Zhengzhong; WANG Liangping; LEI Tianshi; HU Yixiang; HUANG Tao; SUN Tieping

    2012-01-01

    Plasma source performance parameters, including plasma ejection density and velocity, greatly affect the operation of a short-conduction-time plasma opening switch (POS). In this paper, the plasma source used in the POS of Qiangguang I generator is chosen as the study object. At first the POS working process is analyzed. The result shows that the opening performance of the POS can be improved by increasing the plasma ejection velocity and decreasing the plasma density. The influence of the cable plasma gun structure and number on the plasma ejection parameters is experimentally investigated with two charge collectors. Finally a semi-empirical model is proposed to describe the experimental phenomenon.

  7. Negative ion studies on the RF plasma device MAGPIE

    Science.gov (United States)

    Willett, Hannah; Santoso, Jesse; Corr, Cormac; Gibson, Kieran

    2016-10-01

    Neutral beam injection (NBI) systems provide both heating and current drive in tokamak fusion reactors. High energy (> 1 MeV) neutral beams are produced by neutralising accelerated ions, for which negative ions are used; the neutralisation cross section for positive ions becomes negligible at these energies. This requires very high throughput negative ion sources. Currently this is achieved using inductively coupled plasma sources, which incorporate caesium to improve the production rate. It has been proposed that helicon plasma sources could provide a more efficient, higher throughput method of producing negative ions for NBI, possibly even removing the need for caesium. We report on studies of the negative hydrogen ion population in the MAGPIE helicon device (Australian National University) under a variety of operating conditions. The probe-based laser photodetachment method and Langmuir probes are employed to estimate the negative hydrogen ion density throughout the device. Initial results support the viability of helicon-based negative ion sources.

  8. Platelet-rich plasma: updating of extraction devices

    Directory of Open Access Journals (Sweden)

    Raquel Moreno

    2016-12-01

    Full Text Available Propose: To describe PRP extraction devices, through a review of kits available in Spain, taking into account AEMPS and SEFH working groups (GPS, Farmacotecnia, Hemoderivados groups contributions. Methods: Three independent searches about PRP extraction devices were carried out. Device suppliers were contacted and an individually meeting was called with each one. Characteristics of each device was reviewed by virtual demonstration. A kits comparison chart was made with all the information acquired. Kits were classified as Closed-Technique and Opened- Technique in accordance with the AEMPS technical committee report. Results: Ten devices were found: ACP®; Angel®, Cascade®, Endoret ®, GPS®, Magellan®, Minos®, Ortho-pras®, Smart-prepr® and Tricell®. However, we could found out the mechanism in detail of seven of them. Information about Cascade®, Magellan ® and Smart-prepr® kits was not enough. Conclusion: The review provided the main PRP extraction devices available with CE marking and its distinguishing characteristics, however, it is crucial to pay attention to PRP extraction procedure and administration, to guarantee the final product quality. Pharmacy Department must get involved in the device selections due to the close link with the manufactured drug quality. Working together with the AEMPS will contribute to defining extraction procedure specifically.

  9. Negative hydrogen ions in a linear helicon plasma device

    Science.gov (United States)

    Corr, Cormac; Santoso, Jesse; Samuell, Cameron; Willett, Hannah; Manoharan, Rounak; O'Byrne, Sean

    2015-09-01

    Low-pressure negative ion sources are of crucial importance to the development of high-energy (>1 MeV) neutral beam injection systems for the ITER experimental tokamak device. Due to their high power coupling efficiency and high plasma densities, helicon devices may be able to reduce power requirements and potentially remove the need for caesium. In helicon sources, the RF power can be coupled efficiently into the plasma and it has been previously observed that the application of a small magnetic field can lead to a significant increase in the plasma density. In this work, we investigate negative ion dynamics in a high-power (20 kW) helicon plasma source. The negative ion fraction is measured by probe-based laser photodetachment, electron density and temperature are determined by a Langmuir probe and tuneable diode laser absorption spectroscopy is used to determine the density of the H(n = 2) excited atomic state and the gas temperature. The negative ion density and excited atomic hydrogen density display a maximum at a low applied magnetic field of 3 mT, while the electron temperature displays a minimum. The negative ion density can be increased by a factor of 8 with the application of the magnetic field. Spatial and temporal measurements will also be presented. The Australian Research Grants Council is acknowledged for funding.

  10. Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device

    Science.gov (United States)

    Sakuma, I.; Kikuchi, Y.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.

    2015-08-01

    We have developed a unique experimental device of so-called double plasma gun, which consists of two magnetized coaxial plasma gun (MCPG) devices, in order to clarify effects of vapor shielding on material erosion due to transient events in magnetically confined fusion devices. Two ELM-like pulsed plasmas produced by the two MCPG devices were injected into a target chamber with a variable time difference. For generating ablated plasmas in front of a target material, an aluminum foil sample in the target chamber was exposed to a pulsed plasma produced by the 1st MCPG device. The 2nd pulsed plasma was produced with a time delay of 70 μs. It was found that a surface absorbed energy measured by a calorimeter was reduced to ∼66% of that without the Al foil sample. Thus, the reduction of the incoming plasma energy by the vapor shielding effect was successfully demonstrated in the present experiment.

  11. Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device

    Energy Technology Data Exchange (ETDEWEB)

    Sakuma, I., E-mail: eu13z002@steng.u-hyogo.ac.jp; Kikuchi, Y.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.

    2015-08-15

    We have developed a unique experimental device of so-called double plasma gun, which consists of two magnetized coaxial plasma gun (MCPG) devices, in order to clarify effects of vapor shielding on material erosion due to transient events in magnetically confined fusion devices. Two ELM-like pulsed plasmas produced by the two MCPG devices were injected into a target chamber with a variable time difference. For generating ablated plasmas in front of a target material, an aluminum foil sample in the target chamber was exposed to a pulsed plasma produced by the 1st MCPG device. The 2nd pulsed plasma was produced with a time delay of 70 μs. It was found that a surface absorbed energy measured by a calorimeter was reduced to ∼66% of that without the Al foil sample. Thus, the reduction of the incoming plasma energy by the vapor shielding effect was successfully demonstrated in the present experiment.

  12. The ITER full size plasma source device design

    Energy Technology Data Exchange (ETDEWEB)

    Sonato, P. [Consorzio RFX, EURATOM-ENEA Association, Corso Stati Uniti 4, I-35127 Padova (Italy)], E-mail: piergiorgio.sonato@igi.cnr.it; Agostinetti, P.; Anaclerio, G.; Antoni, V.; Barana, O.; Bigi, M.; Boldrin, M. [Consorzio RFX, EURATOM-ENEA Association, Corso Stati Uniti 4, I-35127 Padova (Italy); Cavenago, M. [INFN, Legnaro, Padova (Italy); Dal Bello, S.; Palma, M. Dalla [Consorzio RFX, EURATOM-ENEA Association, Corso Stati Uniti 4, I-35127 Padova (Italy); Daniele, A. [ENEA, Frascati, Roma (Italy); D' Arienzo, M.; De Lorenzi, A.; Ferro, A.; Fiorentin, A.; Gaio, E.; Gazza, E.; Grando, L.; Fantini, F.; Fellin, F. [Consorzio RFX, EURATOM-ENEA Association, Corso Stati Uniti 4, I-35127 Padova (Italy)] (and others)

    2009-06-15

    In the framework of the strategy for the development and the procurement of the NB systems for ITER, it has been decided to build in Padova a test facility, including two experimental devices: a full size plasma source with low voltage extraction and a full size NB injector at full beam power (1 MV). These two different devices will separately address the main scientific and technological issues of the 17 MW NB injector for ITER. In particular the full size plasma source of negative ions will address the ITER performance requirements in terms of current density and uniformity, limitation of the electron/ion ratio and stationary operation at full current with high reliability and constant performances for the whole operating time up to 1 h. The required negative ion current density to be extracted from the plasma source ranges from 290 A/m{sup 2} in D{sub 2} (D{sup -}) and 350 A/m{sup 2} in H{sub 2} (H{sup -}) and these values should be obtained at the lowest admissible neutral pressure in the plasma source volume, nominally at 0.3 Pa. The electron to ion ratio should be limited to less than 1 and the admissible ion inhomogeneity extracted from the grids should be better than 10% on the whole plasma cross-section having a surface exposed to the extraction grid of the order of 1 m{sup 2}. The main design choices will be presented in the paper as well as an overview of the design of the main components and systems.

  13. Dusty Plasma Experimental (DPEx) device for complex plasma experiments with flow

    CERN Document Server

    Jaiswal, S; Sen, A

    2015-01-01

    A versatile table-top dusty plasma experimental device (DPEx) to study flow induced excitations of linear and nonlinear waves/structures in a complex plasma is presented. In this $\\Pi$-shaped apparatus a DC glow discharge plasma is produced between a disc shaped anode and a grounded long cathode tray by applying a high voltage DC in the background of a neutral gas and subsequently a dusty plasma is created by introducing micron sized dust particles that get charged and levitated in the sheath region. A flow of the dust particles is induced in a controlled manner by adjusting the pumping speed and the gas flow rate into the device. A full characterisation of the plasma, using Langmuir and emissive probe data, and that of the dusty plasma using particle tracking data with the help of an idl based (super) Particle Identification and Tracking (sPIT) code is reported. Experimental results on the variation of the dust flow velocity as a function of the neutral pressure and the gas flow rate are given. The potential...

  14. The Origins of Plasmas in the Earth's Neighborhood (OPEN) program

    Science.gov (United States)

    Alexander, J. K.

    1984-01-01

    The nature and objectives of the OPEN program are overviewed. The Origins of Plasmas in the Earth's Neighborhood program was conceived in 1979 and proposed as a major new initiative to study the energetics of the earth's space environment by the end of the 1980s. The objectives of OPEN have been integrated into the Global Geospace Study (GGS) segment to the International Solar-Terrestrial Physics (ISTP) program now being planned jointly by NASA, ESA, and Japan. The goals will be to develop a global understanding of the flow of energy from the sun through the earth's space environment above the neutral atmosphere and to define the cause and effect relationships between the plasma physics processes that link different regions of this dynamic environment. A network of four spacecraft will be used, each one carrying an instrument complement to characterize the composition and behavior of the upstream solar wind, the high-altitude polar magnetosphere, the equatorial magnetosphere, and the comet-like geomagnetic tail. Multispectral cameras will also be carried to image polar auroras at ultraviolet, visible and X-ray wavelengths. Experimentalists and theorists on the international team will participate.

  15. A compact plasma focus device and its neutron emission

    Institute of Scientific and Technical Information of China (English)

    王新新; 韩旻; 王志文; 刘坤

    1999-01-01

    A 2.2-kJ compact plasma focus device was developed and its characteristics of neutron emission were investigated. A maximum neutron yield of (3.1 ± 1.5) × 10~7 was obtained at 15 hPa deuterium filling pressure. It was found that the neutron yield Y_n is strongly correlated with the amplitude of the pinch dip in di/dt waveform. The time resolved measurement of the neutron pulse indicated that both the hard X-rays and the neutrons are emitted from plasma focus at the same instant and the width of neutron pulse (FWHM) changes slightly from 50 to 53 ns. The pinch time t_p varies from 1.5 to 16.5 ns and it is usually the case that the shorter t_p, the higher the neutron yield. It was also found that the squirrel cage cathode is better than the tubular cathode.

  16. Experimental results of breakdown in "Dena" plasma focus device

    Science.gov (United States)

    Goudarzi, Shervin; Hoseinian, S. M.; Raeisdana, A.

    2014-06-01

    In spite of the intense research activities on Plasma Focus devices, the physics of the initial breakdown and surface discharge phase has not been realized completely. In this paper we have analyzed the surface discharge and initial breakdown phase in Filippov-type Plasma Focus Facility "Dena" (90 kJ, 25 kV) on the base of the current and current derivative measured signals by using Argon, Neon and Krypton as working gases at different discharge voltages and gas pressures, and the effects of working conditions (atomic weight, discharge voltage and gas pressure) on the breakdown and surface discharge phase have expressed. Also, on the base of these results, we have investigated about the relation of this phase with final pinch phase.

  17. Plasma effect in Silicon Charge Couple Devices (CCDs)

    CERN Document Server

    Estrada, Juan; Blostein, J

    2011-01-01

    Plasma effect is observed in CCDs exposed to heavy ionizing alpha-particles with energies in the range 0.5 - 5.5 MeV. The results obtained for the size of the charge clusters reconstructed on the CCD pixels agrees with previous measurements in the high energy region (>3.5 MeV). The measurements were extended to lower energies using alpha-particles produced by (n,alpha) reactions of neutrons in a Boron-10 target. The effective linear charge density for the plasma column is measured as a function of energy. The results demonstrate the potential for high position resolution in the reconstruction of alpha particles, which opens an interesting possibility for using these detectors in neutron imaging applications.

  18. Plasma effect in silicon charge coupled devices (CCDs)

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, J., E-mail: estrada@fnal.gov [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Molina, J., E-mail: jmolina@ing.una.py [Facultad de Ingenieria, Universidad Nacional de Asuncion, Laboratorio de Mecanica y Energia, Campus de la UNA, San Lorenzo 2160 (Paraguay); Blostein, J.J., E-mail: jeronimo@cab.cnea.gov.ar [CONICET (Argentina); Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Bariloche (Argentina); Fernandez, G., E-mail: fmoroni.guillermo@gmail.com [Universidad Nacional del Sur, Bahia Blanca (Argentina)

    2011-02-11

    Plasma effect is observed in CCDs exposed to heavy ionizing {alpha}-particles with energies in the range 0.5-5.5 MeV. The results obtained for the size of the charge clusters reconstructed on the CCD pixels agree with previous measurements in the high energy region ({>=}3.5 MeV). The measurements were extended to lower energies using {alpha}-particles produced by (n,{alpha}) reactions of neutrons in a {sup 10}B target. The effective linear charge density for the plasma column is measured as a function of energy. The results demonstrate the potential for high position resolution in the reconstruction of {alpha} particles, which opens an interesting possibility for using these detectors in neutron imaging applications.

  19. Versatile and Rapid Plasma Heating Device for Steel and Aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, G.S.

    2006-03-14

    The main objective of the research was to enhance steel and aluminum manufacturing with the development of a new plasma RPD device. During the project (1) plasma devices were manufactured (2) testing for the two metals were carried out and (3) market development strategies were explored. Bayzi Corporation has invented a Rapid Plasma Device (RPD) which produces plasma, comprising of a mixture of ionized gas and free electrons. The ions, when they hit a conducting surface, deposit heat in addition to the convective heat. Two generic models called the RPD-Al and RPD-S have been developed for the aluminum market and the steel market. Aluminum melting rates increased to as high as 12.7 g/s compared to 3 g/s of the current industrial practice. The RPD melting furnace operated at higher energy efficiency of 65% unlike most industrial processes operating in the range of 13 to 50%. The RPD aluminum melting furnace produced environment friendly cleaner melts with less than 1% dross. Dross is the residue in the furnace after the melt is poured out. Cast ingots were extremely clean and shining. Current practices produce dross in the range of 3 to 12%. The RPD furnace uses very low power ~0.2 kWh/Lb to melt aluminum. RPDs operate in one atmosphere using ambient air to produce plasma while the conventional systems use expensive gases like argon, or helium in air-tight chambers. RPDs are easy to operate and do not need intensive capital investment. Narrow beam, as well as wide area plasma have been developed for different applications. An RPD was developed for thermal treatments of steels. Two different applications have been pursued. Industrial air hardening steel knife edges were subjected to plasma beam hardening. Hardness, as measured, indicated uniform distribution without any distortion. The biggest advantage with this method is that the whole part need not be heated in a furnace which will lead to oxidation and distortion. No conventional process will offer localized

  20. Ion Current Collection Diagnostic for the Triggered Plasma Opening Switch Experiment

    Science.gov (United States)

    Jackson, D. P.; Gilmore, M. A.

    2005-10-01

    The novel Triggered Plasma Opening Switch (TPOS) is a unique device that exploits the high conductivity and low mass properties of plasma. The TPOS's objective is to take the initial ˜.8 MA (˜250 ns rise time) storage inductor current and deliver ˜.5 MA at ˜2.5 MV (˜10ns rise time) to a load of ˜5-10 φ. Study of the TPOS characteristics is in progress via an Ion Current Collection Diagnostic (ICCD). The ICCD has been designed, fabricated, tested, and is in use on the TPOS in order to explore the main switch opening profile. The ICCD utilizes 12 charge collectors (biased faraday cups) that are positioned perpendicularly to the main switch stage in order to collect radially traveling ions emitted from the plasma surface via the Child-Langmuir law. Magnetostatic simulations with self consistent space charge emitting surfaces of the main switch using the Trak static 2D finite element code have been conducted as well. Finally, ICCD experimental data have been recorded, and hopefully these data will provide evidence that support both theory and simulation.

  1. Device and method for treatment of openings in vascular and septal walls

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, Pooja; Wilson, Thomas S.; Cosgriff-Hernandez, Elizabeth; Maitland, Duncan J.

    2017-06-06

    A device, system and method for treatment of an opening in vascular and/or septal walls including patent foramen ovale. The device has wings/stops on either end, an axis core covered in a shape memory foam and is deliverable via a catheter to the affected opening, finally expanding into a vascular or septal opening where it is held in place by the expandable shape memory stops or wings.

  2. Experimental determination of gap scaling in a plasma opening switch

    Science.gov (United States)

    Black, D. C.; Commisso, R. J.; Ottinger, P. F.; Swanekamp, S. B.; Weber, B. V.

    2000-09-01

    Experiments were performed to investigate the coupling between a ˜0.5 μs conduction-time, ˜0.5 MA conduction-current plasma opening switch (POS), and an electron-beam (e-beam) diode. Electrical diagnostics provided measurements of the voltage at the oil-vacuum insulator and at the diode as well as anode and cathode currents on the generator and load sides of the POS. These measurements were combined with a flow impedance model to determine the POS gap over a range of conduction times and e-beam diode impedances, and for two POS-to-load distances. A comparison of the inferred POS gap at peak power with the critical gap for magnetic insulation indicates that the POS gap is always saturated in both switch-limited and load-limited regimes. This POS gap-size scaling with load impedance is consistent with an opening mechanism dominated by erosion and not J×B forces.

  3. Characterization of bismuth nanospheres deposited by plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, M., E-mail: cscientific2@aec.org.sy [IBA Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic); Al-Hawat, Sh.; Akel, M. [Physics Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic); Mrad, O. [Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2015-02-14

    A new method for producing thin layer of bismuth nanospheres based on the use of low energy plasma focus device is demonstrated. Various techniques such as scanning electron microscopy, Rutherford backscattering spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy have been used to characterize the morphology and the composition of the nanospheres. Experimental parameters may be adjusted to favour the formation of bismuth nanospheres instead of microspheres. Therefore, the formation of large surface of homogeneous layer of bismuth nanospheres with sizes of below 100 nm can be obtained. The natural snowball phenomenon is observed to be reproduced in nanoscale where spheres roll over the small nanospheres and grow up to bigger sizes that can reach micro dimensions. The comet-like structure, a reverse phenomenon to snowball is also observed.

  4. Nonlinear instability in simulations of Large Plasma Device turbulence

    CERN Document Server

    Friedman, B; Umansky, M V; Schaffner, D; Joseph, I

    2013-01-01

    Several simulations of turbulence in the Large Plasma Device (LAPD) [W. Gekelman et al., Rev. Sci. Inst. 62, 2875 (1991)] are energetically analyzed and compared with each other and with the experiment. The simulations use the same model, but different axial boundary conditions. They employ either periodic, zero-value, zero-derivative, or sheath axial boundaries. The linear stability physics is different between the scenarios because the various boundary conditions allow the drift wave instability to access different axial structures, and the sheath boundary simulation contains a conducting wall mode instability which is just as unstable as the drift waves. Nevertheless, the turbulence in all the simulations is relatively similar because it is primarily driven by a robust nonlinear instability that is the same for all cases. The nonlinear instability preferentially drives $k_\\parallel = 0$ potential energy fluctuations, which then three-wave couple to $k_\\parallel \

  5. Preliminary Results Of A 600 Joules Small Plasma Focus Device

    Science.gov (United States)

    Lee, S. H.; Yap, S. L.; Wong, C. S.

    2009-07-01

    Preliminary results of a 600 J (3.7 μF, 18 kV) Mather type plasma focus device operated at low pressure will be presented. The discharge is formed between a solid anode with length of 6 cm and six symmetrically and coaxially arranged cathode rods of same lengths. The cathode base is profiled in a knife-edge design and a set of coaxial plasma gun are attached to it in order to initiate the breakdown and enhance the current sheath formation. The experiments have been performed in argon gas under a low pressure condition of several microbars. The discharge current and the voltage across the electrodes during the discharge are measured with high voltage probe and current coil. The current and voltage characteristics are used to determine the possible range of operating pressure that gives good focusing action. At a narrow pressure regime of 9.0±0.5 μbar, focusing action is observed with good reproducibility. Preliminary result of ion beam energy is presented. More work will be carried out to investigate the radiation output.

  6. Hard X-ray sources from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Silva, P.; Moreno, J.; Zambra, M.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  7. Enabling a Uniform OpenCL Device View for Heterogeneous Platforms

    National Research Council Canada - National Science Library

    HUANG, Dafei; XUN, Changqing; WU, Nan; WEN, Mei; ZHANG, Chunyuan; CAI, Xing; YANG, Qianming

    2015-01-01

    Aiming to ease the parallel programming for heterogeneous architectures, we propose and implement a high-level OpenCL runtime that conceptually merges multiple heterogeneous hardware devices into one...

  8. Palm top plasma focus device as a portable pulsed neutron source.

    Science.gov (United States)

    Rout, R K; Niranjan, Ram; Mishra, P; Srivastava, R; Rawool, A M; Kaushik, T C; Gupta, Satish C

    2013-06-01

    Development of a palm top plasma focus device generating (5.2 ± 0.8) × 10(4) neutrons∕pulse into 4π steradians with a pulse width of 15 ± 3 ns is reported for the first time. The weight of the system is less than 1.5 kg. The system comprises a compact capacitor bank, a triggered open air spark gap switch, and a sealed type miniature plasma focus tube. The setup is around 14 cm in diameter and 12.5 cm in length. The energy driver for the unit is a capacitor bank of four cylindrical commercially available electrolytic capacitors. Each capacitor is of 2 μF capacity, 4.5 cm in diameter, and 9.8 cm in length. The cost of each capacitor is less than US$ 10. The internal diameter and the effective length of the plasma focus unit are 2.9 cm and 5 cm, respectively. A DC to DC converter power supply powered by two rechargeable batteries charges the capacitor bank to the desired voltage and also provides a trigger pulse of -15 kV to the spark gap. The maximum energy of operation of the device is 100 J (8 μF, 5 kV, 59 kA) with deuterium gas filling pressure of 3 mbar. The neutrons have also been produced at energy as low as 36 J (3 kV) of operation. The neutron diagnostics are carried out with a bank of (3)He detectors and with a plastic scintillator detector. The device is portable, reusable, and can be operated for multiple shots with a single gas filling.

  9. On the history of plasma treatment and comparison of microbiostatic efficacy of a historical high-frequency plasma device with two modern devices

    Directory of Open Access Journals (Sweden)

    Napp, Judith

    2015-06-01

    Full Text Available Background: Cold atmospheric pressure plasma (CAP with its many bioactive properties has defined a new medical field: the plasma medicine. However, in the related form of high-frequency therapy, CAP was even used briefly a century ago. The aim of this study was to review historic CAP treatments and to obtain data regarding the antimicrobial efficacy of a historical high-frequency plasma device.Methods: First, historic literature regarding the history of CAP treatment was evaluated, because in the modern literature no data were available. Second, the susceptibility of 5 different bacterial wound isolates, cultured on agar, to a historic plasma source (violet wand [VW] and two modern devices (atmospheric pressure plasma jet [APPJ] and Dielectric Barrier Discharge [DBD] was analyzed . The obtained inhibition areas (IA were compared.Results: First, the most convenient popular historical electromedical treatments produced a so-called effluvia by using glass electrodes, related to today’s CAP. Second, all three tested plasma sources showed complete eradication of all tested microbial strains in the treated area. The “historical” cold VW plasma showed antimicrobial effects similar to those of modern APPJ and DBD regarding the diameter of the IA.Conclusion: Some retrograde evidence may be deducted from this, especially for treatment of infectious diseases with historical plasma devices. The underlying technology may serve as model for construction of modern sucessive devices.

  10. Simulations with Conventional and Gas Puff Plasma Focus Devices

    Science.gov (United States)

    Shan, Bing; Liu, Mahe; Lee, Paul; Lee, Sing

    2000-10-01

    An energy consistent plasma focus model is improved by considering the plasma ionization states based on the corona equilibrium. This provides the model with the capability of calculating the plasma dynamics and states for different gases in plasma focus. The model is employed to simulate the behavior of the NX2 plasma focus, with both neon and argon gases. The results show that much lower pressure is required to work with argon for x-ray. The model has also been modified to describe a gas-puff plasma focus based on a measured pressure distribution profile. The simulation result reveals that the gas-puff scheme is more efficient in plasma heating and can improve the stability of the plasma column. By comparing with the published results, agreements have been obtained between the computations and experiments of both machines in the major points regarding plasma dynamics, plasma column stability and appearances, plasma temperatures, and x-ray radiation properties.

  11. Iliac branched device implantation in tortuous iliac anatomy after previous open ruptured aortic aneurysm repair

    NARCIS (Netherlands)

    Vourliotakis, G.; Bracale, U. M.; Sondakh, A.; Tielliu, I. F. J.; Prins, T. R.; Verhoeven, E. L. G.

    2012-01-01

    The aim of this paper was to present iliac branched device (IBD) implantation in a fit 67-year-old man with tortuous iliac anatomy after previous emergent open abdominal aortic aneurysm (AAA) repair. The patient underwent open treatment for a ruptured abdominal aortic aneurysm in another hospital. T

  12. A Novel Continuously Initiated Polymerization by One-Atmosphere Low Temperature Plasma Device

    Institute of Scientific and Technical Information of China (English)

    You qingliang; Meng yuedong; Wang jianhua; Ou qiongrong; Xu xu; Zhong shaofeng

    2005-01-01

    A novel atmospheric plasma device developed in this paper, which is more effective and convenient to study the plasma-initiated polymerization (PIP) than conventional setup. The structure and mechanism of the device is introduced. Some plasma-initiated polymerization experiments are carried out on the device, and the conversion of AA (Acrylic acid) and AM (Acryl amide) atmospheric (N2) plasma polymerization are respectively 89% and 94% after 120 h post polymerization, whereby IR spectra of the product (AA, AM). Our PIP result are confirmed.

  13. Interaction of powerful hot plasma and fast ion streams with materials in dense plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Chernyshova, M., E-mail: maryna.chernyshova@ipplm.pl [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Gribkov, V.A. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Institution of Russian Academy of Sciences A.A. Baikov Institute of Metallurgy and Material Science RAS, Moscow (Russian Federation); Kowalska-Strzeciwilk, E.; Kubkowska, M.; Miklaszewski, R.; Paduch, M.; Pisarczyk, T.; Zielinska, E. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Demina, E.V.; Pimenov, V.N.; Maslyaev, S.A. [Institution of Russian Academy of Sciences A.A. Baikov Institute of Metallurgy and Material Science RAS, Moscow (Russian Federation); Bondarenko, G.G. [National Research University Higher School of Economics (HSE), Moscow (Russian Federation); Vilemova, M.; Matejicek, J. [Institute of Plasma Physics of the CAS, Prague (Czech Republic)

    2016-12-15

    Highlights: • Materials perspective for use in mainstream nuclear fusion facilities were studied. • Powerful streams of hot plasma and fast ions were used to induce irradiation. • High temporal, spatial, angular and spectral resolution available in experiments. • Results of irradiation were investigated by number of analysis techniques. - Abstract: A process of irradiating and ablating solid-state targets with hot plasma and fast ion streams in two Dense Plasma Focus (DPF) devices – PF-6 and PF-1000 was examined by applying a number of diagnostics of nanosecond time resolution. Materials perspective for use in chambers of the mainstream nuclear fusion facilities (mainly with inertial plasma confinement like NIF and Z-machine), intended both for the first wall and for constructions, have been irradiated in these simulators. Optical microscopy, SEM, Atomic Emission Spectroscopy, images in secondary electrons and in characteristic X-ray luminescence of different elements, and X-ray elemental analysis, gave results on damageability for a number of materials including low-activated ferritic and austenitic stainless steels, β-alloy of Ti, as well as two types of W and a composite on its base. With an increase of the number of shots irradiating the surface, its morphology changes from weakly pronounced wave-like structures or ridges to strongly developed ones. At later stages, due to the action of the secondary plasma produced near the target materials they melted, yielding both blisters and a fracturing pattern: first along the grain and then “in-between” the grains creating an intergranular net of microcracks. At the highest values of power flux densities multiple bubbles appeared. Furthermore, in this last case the cracks were developed because of microstresses at the solidification of melt. Presence of deuterium within the irradiated ferritic steel surface nanolayers is explained by capture of deuterons in lattice defects of the types of impurity atoms

  14. A Self-Provisioning Mechanism in OpenStack for IoT Devices

    Science.gov (United States)

    Solano, Antonio; Dormido, Raquel; Duro, Natividad; Sánchez, Juan Miguel

    2016-01-01

    The aim of this paper is to introduce a plug-and-play mechanism for an Internet of Things (IoT) device to instantiate a Software as a Service (SaaS) application in a private cloud, built up with OpenStack. The SaaS application is the digital avatar of a physical object connected to Internet. As a proof of concept, a Vending Machine is retrofitted and connected to Internet with and Arduino Open Hardware device. Once the self-configuration mechanism is completed, it is possible to order a product from a mobile communication device. PMID:27548166

  15. A Self-Provisioning Mechanism in OpenStack for IoT Devices.

    Science.gov (United States)

    Solano, Antonio; Dormido, Raquel; Duro, Natividad; Sánchez, Juan Miguel

    2016-08-17

    The aim of this paper is to introduce a plug-and-play mechanism for an Internet of Things (IoT) device to instantiate a Software as a Service (SaaS) application in a private cloud, built up with OpenStack. The SaaS application is the digital avatar of a physical object connected to Internet. As a proof of concept, a Vending Machine is retrofitted and connected to Internet with and Arduino Open Hardware device. Once the self-configuration mechanism is completed, it is possible to order a product from a mobile communication device.

  16. A Self-Provisioning Mechanism in OpenStack for IoT Devices

    Directory of Open Access Journals (Sweden)

    Antonio Solano

    2016-08-01

    Full Text Available The aim of this paper is to introduce a plug-and-play mechanism for an Internet of Things (IoT device to instantiate a Software as a Service (SaaS application in a private cloud, built up with OpenStack. The SaaS application is the digital avatar of a physical object connected to Internet. As a proof of concept, a Vending Machine is retrofitted and connected to Internet with and Arduino Open Hardware device. Once the self-configuration mechanism is completed, it is possible to order a product from a mobile communication device.

  17. Complex plasma experimental device – A test bed for studying dust vortices and other collective phenomena

    Indian Academy of Sciences (India)

    MANJIT KAUR; SAYAK BOSE; P K CHATTOPADHYAY; J GHOSH; Y C SAXENA

    2016-12-01

    A typical device for carrying out sophisticated and complex dusty plasma experiments is designed, fabricated and made operational at the Institute for Plasma Research, India. The device is named as complex plasma experimental device (CPED). The main aim of this multipurpose machine is to study the formation and behaviour of dust vortices in the absence of external magnetic field under the effect of various plasma parameters. Further, the device is equipped with advanced imaging diagnostics for studying many other interesting phenomena such as dust oscillations, three-dimensional crystalline structures, dust rotation, etc. The device is quite flexible to accommodate many innovative experiments. Detailed design of the device, its diagnostics capabilities and theadvanced image analysis techniques are presented in this paper.

  18. The Dynamics of an Isolated Plasma Filament at the Edge of a Toroidal Device, Rev. 1

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D D

    2006-09-28

    The dynamics of an isolated plasma filament (an isolated blob) in the far scrape-off layer (SOL) of a toroidal device is described, with a proper averaging of the geometrical parameters as well as plasma parameters along the filament. The analysis is limited to the magnetohydrodynamic description. The effects of the anchored ends and finite plasma resistivity are also discussed.

  19. High density and high temperature plasmas in Large Helical Device

    Science.gov (United States)

    Komori, Akio

    2010-11-01

    Recently a new confinement regime called Super Dense Core (SDC) mode was discovered in Large Helical Device (LHD). An extremely high density core region with more than ~ 1 × 1021 m-3 is obtained with the formation of an Internal Diffusion Barrier (IDB). The density gradient at the IDB is very high and the particle confinement in the core region is ~ 0.2 s. It is expected, for the future reactor, that the IDB-SDC mode has a possibility to achieve the self-ignition condition with lower temperature than expected before. Conventional approaches to increase the temperature have also been tried in LHD. For the ion heating, the perpendicular neutral beam injection effectively increased the ion temperature up to 5.6 keV with the formation of the internal transport barrier (ITB). In the electron heating experiments with 77 GHz gyrotrons, the highest electron temperature more than 15 keV was achieved, where plasmas are in the neoclassical regime.

  20. High density and high temperature plasmas in Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Komori, Akio, E-mail: komori@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan)

    2010-11-01

    Recently a new confinement regime called Super Dense Core (SDC) mode was discovered in Large Helical Device (LHD). An extremely high density core region with more than {approx} 1 x 10{sup 21} m{sup -3} is obtained with the formation of an Internal Diffusion Barrier (IDB). The density gradient at the IDB is very high and the particle confinement in the core region is {approx} 0.2 s. It is expected, for the future reactor, that the IDB-SDC mode has a possibility to achieve the self-ignition condition with lower temperature than expected before. Conventional approaches to increase the temperature have also been tried in LHD. For the ion heating, the perpendicular neutral beam injection effectively increased the ion temperature up to 5.6 keV with the formation of the internal transport barrier (ITB). In the electron heating experiments with 77 GHz gyrotrons, the highest electron temperature more than 15 keV was achieved, where plasmas are in the neoclassical regime.

  1. Impurity screening and edge-plasma modifications for plasma devices with liquid walls.

    Science.gov (United States)

    Rognlien, Thomas D.

    2001-10-01

    The edge-plasma region of magnetic fusion confinement devices plays various important roles, two of which are (1), shielding the core plasma from gas and impurities, and (2), influencing the core-boundary plasma temperature and density. The first role is crucial to the successful use of liquid walls, and the second role, if controllable, could enhance core energy confinement by reducing drives for core turbulence. In fusion reactors, liquid walls would allow higher wall power-loading, and sufficiently thick walls would greatly reduce neutron activation of support structures.(R.W. Moir, Nucl. Fusion 37), 557 (1997); M. Abdou, et al., Fusion Eng. Design 54, 181 (2001). In addition, liquid divertors could largely eliminate the surface erosion problem.(J.N. Brooks, et al.), J. Nucl. Mater. 290-293, 185 (2001.); R.F. Mattas, et al., Fusion Eng. Design 49-50, 127 (2000). In this talk, results of self-consistent, 2-D edge transport simulations are presented to quantify the allowable influx of liquid-wall vapor for various candidate liquids (Li, Flibe, SnLi, Sn) which, in turn, set the allowable surface operating temperatures that controls the vapor evaporation rates. The results are explained and summarized by a reduced model that includes the radiation characteristics of different impurity species, and the competition between anomalous radial transport and parallel flow along the B-field. The modification of the edge plasma properties by liquid walls is also presented, with an emphasis on the low-recycling regime thought possible by the use of lithium, which naturally leads to a high edge-temperature regime. The effect of long mean-free-path parallel transport in the high-temperature regime is described by the bounce-averaged, particle- and energy-loss model.

  2. New linear plasma devices in the trilateral euregio cluster for an integrated approach to plasma surface interactions in fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Unterberg, B., E-mail: b.unterberg@fz-juelich.de [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM- Forschungszentrum Juelich, D-52425 Juelich (Germany); Jaspers, R. [Science and Technology of Nuclear Fusion, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Koch, R. [Laboratoire de Physique des Plasmas/Laboratorium voor Plasmafysica, ERM/KMS, EURATOM-Association, B-1000 Brussels (Belgium); Massaut, V. [SCK-CEN, Belgian Nuclear Research Centre, EURATOM-Association, Boeretang 200, 2400 Mol (Belgium); Rapp, J. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Reiter, D.; Kraus, S.; Kreter, A.; Philipps, V.; Reimer, H.; Samm, U.; Scheibl, L.; Schweer, B. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM- Forschungszentrum Juelich, D-52425 Juelich (Germany); Schuurmans, J.; Uytdenhouwen, I. [SCK-CEN, Belgian Nuclear Research Centre, EURATOM-Association, Boeretang 200, 2400 Mol (Belgium); Al, R.; Berg, M.A. van den; Brons, S.; Eck, H.J.N. van; Goedheer, W.J. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, PO Box 1207, 3430 BE Nieuwegein (Netherlands)

    2011-10-15

    New linear plasma devices are currently being constructed or planned in the Trilateral Euregio Cluster (TEC) to meet the challenges with respect to plasma surface interactions in DEMO and ITER: i) MAGNUM-PSI (FOM), a high particle and power flux device with super-conducting magnetic field coils which will reach ITER-like divertor conditions at high magnetic field, ii) the newly proposed linear plasma device JULE-PSI (FZJ), which will allow to expose toxic and neutron activated target samples to ITER-like fluences and ion energies including in vacuo analysis of neutron activated samples, and iii) the plasmatron VISION I, a compact plasma device which will be operated inside the tritium lab at SCK-CEN Mol, capable to investigate tritium plasmas and moderately activated wall materials. This contribution shows the capabilities of the new devices and their forerunner experiments (Pilot-PSI at FOM and PSI-2 Juelich at FZJ) in view of the main objectives of the new TEC program on plasma surface interactions.

  3. Platelet-rich plasma: updating of extraction devices

    OpenAIRE

    Raquel Moreno; Marisa Gaspar Carreño; Jose María Alonso Herreros; Jose Antonio Romero Garrido; Piedad López-Sánchez

    2016-01-01

    Propose: To describe PRP extraction devices, through a review of kits available in Spain, taking into account AEMPS and SEFH working groups (GPS, Farmacotecnia, Hemoderivados groups) contributions. Methods: Three independent searches about PRP extraction devices were carried out. Device suppliers were contacted and an individually meeting was called with each one. Characteristics of each device was reviewed by virtual demonstration. A kits comparison chart was made with all the informatio...

  4. On the plasma chemistry of a cold atmospheric argon plasma jet with shielding gas device

    Science.gov (United States)

    Schmidt-Bleker, Ansgar; Winter, Jörn; Bösel, André; Reuter, Stephan; Weltmann, Klaus-Dieter

    2016-02-01

    A novel approach combining experimental and numerical methods for the study of reaction mechanisms in a cold atmospheric \\text{Ar} plasma jet is introduced. The jet is operated with a shielding gas device that produces a gas curtain of defined composition around the plasma plume. The shielding gas composition is varied from pure {{\\text{N}}2} to pure {{\\text{O}}2} . The density of metastable argon \\text{Ar}≤ft(4\\text{s}{{,}3}{{\\text{P}}2}\\right) in the plasma plume was quantified using laser atom absorption spectroscopy. The density of long-living reactive oxygen and nitrogen species (RONS), namely {{\\text{O}}3} , \\text{N}{{\\text{O}}2} , \\text{NO} , {{\\text{N}}2}\\text{O} , {{\\text{N}}2}{{\\text{O}}5} and {{\\text{H}}2}{{\\text{O}}2} , was quantified in the downstream region of the jet in a multipass cell using Fourier-transform infrared spectroscopy (FTIR). The jet produces a turbulent flow field and features guided streamers propagating at several \\text{km}~{{\\text{s}}-1} that follow the chaotic argon flow pattern, yielding a plasma plume with steep spatial gradients and a time dependence on the \\text{ns} scale while the downstream chemistry unfolds within several seconds. The fast and highly localized electron impact reactions in the guided streamer head and the slower gas phase reactions of neutrals occurring in the plasma plume and experimental apparatus are therefore represented in two separate kinetic models. The first electron impact reaction kinetics model is correlated to the LAAS measurements and shows that in the guided streamer head primary reactive oxygen and nitrogen species are dominantly generated from \\text{Ar}≤ft(4\\text{s}{{,}3}{{\\text{P}}2}\\right) . The second neutral species plug-flow model hence uses an \\text{Ar}≤ft(4\\text{s}{{,}3}{{\\text{P}}2}\\right) source term as sole energy input and yields good agreement with the RONS measured by FTIR spectroscopy.

  5. An Inexpensive, Open-Source USB Arduino Data Acquisition Device for Chemical Instrumentation.

    Science.gov (United States)

    Grinias, James P; Whitfield, Jason T; Guetschow, Erik D; Kennedy, Robert T

    2016-07-12

    Many research and teaching labs rely on USB data acquisition devices to collect voltage signals from instrumentation. However, these devices can be cost-prohibitive (especially when large numbers are needed for teaching labs) and require software to be developed for operation. In this article, we describe the development and use of an open-source USB data acquisition device (with 16-bit acquisition resolution) built using simple electronic components and an Arduino Uno that costs under $50. Additionally, open-source software written in Python is included so that data can be acquired using nearly any PC or Mac computer with a simple USB connection. Use of the device was demonstrated for a sophomore-level analytical experiment using GC and a CE-UV separation on an instrument used for research purposes.

  6. Opening Switch Research on a Plasma Focus VI.

    Science.gov (United States)

    1988-02-26

    densi y ( -’cm-3 suggest that th. I asma is at max imu: compress ion. Xna xxmmn1m AVI JulmrW0 51 (a) PLASMA DENSITY (SCALE: 1.0=1.6- 1018CM-3 ) 1.0 .4 7...IEEE inter. Pulsed Power Conf., New Mexico , 350 (1983). 3. F. Venneri, and G. Gerdin, IEEE Int. Conf. on Plasma Sci., St. Louis, MO, 1984, Conf. Record

  7. Open-loop versus closed-loop control of MEMS devices: choices and issues

    Science.gov (United States)

    Borovic, B.; Liu, A. Q.; Popa, D.; Cai, H.; Lewis, F. L.

    2005-10-01

    From a controls point of view, micro electromechanical systems (MEMS) can be driven in an open-loop and closed-loop fashion. Commonly, these devices are driven open-loop by applying simple input signals. If these input signals become more complex by being derived from the system dynamics, we call such control techniques pre-shaped open-loop driving. The ultimate step for improving precision and speed of response is the introduction of feedback, e.g. closed-loop control. Unlike macro mechanical systems, where the implementation of the feedback is relatively simple, in the MEMS case the feedback design is quite problematic, due to the limited availability of sensor data, the presence of sensor dynamics and noise, and the typically fast actuator dynamics. Furthermore, a performance comparison between open-loop and closed-loop control strategies has not been properly explored for MEMS devices. The purpose of this paper is to present experimental results obtained using both open- and closed-loop strategies and to address the comparative issues of driving and control for MEMS devices. An optical MEMS switching device is used for this study. Based on these experimental results, as well as computer simulations, we point out advantages and disadvantages of the different control strategies, address the problems that distinguish MEMS driving systems from their macro counterparts, and discuss criteria to choose a suitable control driving strategy.

  8. Carbon nanotube-polybithiophene photovoltaic devices with high open-circuit voltage

    Energy Technology Data Exchange (ETDEWEB)

    Patyk, Rodolfo L.; Huemmelgen, Ivo A. [Departamento de Fisica, Universidade Federal do Parana, Caixa Postal 19044, 81531-990 Curitiba PR (Brazil); Lomba, Bruno S.; Nogueira, Ana Flavia [Laboratorio de Nanotechnologia e Energia Solar, Instituto de Quimica, Unicamp, C.P. 6154, 13084-971 Campinas, Sao Paulo (Brazil); Furtado, Clascidia A.; Santos, Adelina Pinheiro [Laboratorio de Quimica de Nanoestruturas, CDTN/CNEN, Belo Horizonte, MG (Brazil); Mello, Regina M.Q.; Micaroni, Liliana [Departamento de Quimica, Universidade Federal do Parana, Caixa Postal 19081, 81531-990 Curitiba PR (Brazil)

    2007-01-15

    We report the preparation of photovoltaic devices using modified single wall carbon nanotubes, SWNTs. Devices are produced stacking on top of fluorine-doped tin-oxide, an electrochemically deposited polybithiophene layer, a layer of SWNT blended with poly(3-octylthiophene) and an evaporated top metal contact, Ca/Al or Al. Ca/Al-top-electrode devices achieve open-circuit voltages of 1.81 V and average power conversion efficiency of 1.48% at irradiance of 15.5 W m{sup -2}, spectrally distributed following AM1.5. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Magnetic Piston Propagation in a 100-ns Plasma Opening Switch

    Science.gov (United States)

    Weingarten, A.; Grabowski, C.; Chakrabarti, N.; Maron, Y.; Fruchtman, A.

    1998-11-01

    The propagation of a magnetic piston through the plasma of a 90-ns, 170-kA POS is observed by studying the electron density, magnetic field, and ion velocity evolution. For the prefilled plasma n_e=(2.2± 0.5)× 10^14 cm-3, and T_e=5.5± 1 eV. The plasma composition is studied from absolute line intensities and collisional-radiative calculations. Most of the plasma ions are protons (90% near the cathode) with the rest being mainly CIV. The Hall-MHD conditions are not fulfilled for our experiment and ion motion is significant. The 3D-resolved ne evolution during the current pulse is studied from the line intensities of ions doped in the plasma using laser evaporation, and the magnetic field from Zeeman splitting. A diagonal magnetic piston propagates from the generator towards the load at about half the proton Alfven velocity. The protons are specularly reflected by the piston, while the heavy ions cross the potential hill in the piston, acquiring a lower velocity. The proton reflection causes an increase of ne ahead of the piston, followed by a sharp (10-20 ns) and substantial drop in ne (to 10-50% from the initial value). The magnetic field distribution studied using chordal observation, and theoretical analysis of ne and the magnetic field evolution are presented.

  10. DEVICE FOR INVESTIGATION OF MAGNETRON AND PULSED-LASER PLASMA

    Directory of Open Access Journals (Sweden)

    A. P. Burmakov

    2012-01-01

    Full Text Available Various modifications of complex pulsed laser and magnetron deposition thin-film structures unit are presented. They include joint and separate variants of layer deposition. Unit realizes the plasma parameters control and enhances the possibility of laser-plasma and magnetron methods of coatings deposition.

  11. Efficiency of voluntary opening hand and hook prosthetic devices : 24 years of development?

    NARCIS (Netherlands)

    Smit, Gerwin; Bongers, Raoul M.; Van der Sluis, Corry K.; Plettenburg, Dick H.

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adultsize voluntary opening (VU) prosthetic terminal devices and select the

  12. Efficiency of voluntary opening hand and hook prosthetic devices, 24 years of development?

    NARCIS (Netherlands)

    Smit, G.; Bongers, R.M.; Van der Sluis, C.K.; Plettenburg, D.H.

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO) prosthetic terminal devices and select the

  13. Efficiency of voluntary opening hand and hook prosthetic devices : 24 years of development?

    NARCIS (Netherlands)

    Smit, Gerwin; Bongers, Raoul M.; Van der Sluis, Corry K.; Plettenburg, Dick H.

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adultsize voluntary opening (VU) prosthetic terminal devices and select the be

  14. Efficiency of voluntary opening hand and hook prosthetic devices, 24 years of development?

    NARCIS (Netherlands)

    Smit, G.; Bongers, R.M.; Van der Sluis, C.K.; Plettenburg, D.H.

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO) prosthetic terminal devices and select the b

  15. An open-source framework for testing tracking devices using Lego Mindstorms

    Science.gov (United States)

    Jomier, Julien; Ibanez, Luis; Enquobahrie, Andinet; Pace, Danielle; Cleary, Kevin

    2009-02-01

    In this paper, we present an open-source framework for testing tracking devices in surgical navigation applications. At the core of image-guided intervention systems is the tracking interface that handles communication with the tracking device and gathers tracking information. Given that the correctness of tracking information is critical for protecting patient safety and for ensuring the successful execution of an intervention, the tracking software component needs to be thoroughly tested on a regular basis. Furthermore, with widespread use of extreme programming methodology that emphasizes continuous and incremental testing of application components, testing design becomes critical. While it is easy to automate most of the testing process, it is often more difficult to test components that require manual intervention such as tracking device. Our framework consists of a robotic arm built from a set of Lego Mindstorms and an open-source toolkit written in C++ to control the robot movements and assess the accuracy of the tracking devices. The application program interface (API) is cross-platform and runs on Windows, Linux and MacOS. We applied this framework for the continuous testing of the Image-Guided Surgery Toolkit (IGSTK), an open-source toolkit for image-guided surgery and shown that regression testing on tracking devices can be performed at low cost and improve significantly the quality of the software.

  16. Production of high transient heat and particle fluxes in a linear plasma device

    NARCIS (Netherlands)

    De Temmerman, G.; Zielinski, J. J.; van der Meiden, H.; Melissen, W.; Rapp, J.

    2010-01-01

    We report on the generation of high transient heat and particle fluxes in a linear plasma device by pulsed operation of the plasma source. A capacitor bank is discharged into the source to transiently increase the discharge current up to 1.7 kA, allowing peak densities and temperature of 70x10(20) m

  17. On the evolution of jet energy and opening angle in strongly coupled plasma

    Energy Technology Data Exchange (ETDEWEB)

    Chesler, Paul M. [Department of Physics, Harvard University,Cambridge MA 02138 (United States); Rajagopal, Krishna [Center for Theoretical Physics, MIT,Cambridge MA 02139 (United States)

    2016-05-17

    We calculate how the energy and the opening angle of jets in N=4 SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE{sub jet}/dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE{sub jet}/dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say the opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that N=4 SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the N=4 SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. We close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.

  18. Efficiency of voluntary opening hand and hook prosthetic devices: 24 years of development?

    Science.gov (United States)

    Smit, Gerwin; Bongers, Raoul M; Van der Sluis, Corry K; Plettenburg, Dick H

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO) prosthetic terminal devices and select the best tested device. A second goal was to see whether VO devices have improved in the last two decades. Nine devices (four hooks and five hands) were quantitatively tested (Hosmer model 5XA hook, Hosmer Sierra 2 Load VO hook, RSL Steeper Carbon Gripper, Otto Bock model 10A60 hook, Becker Imperial hand, Hosmer Sierra VO hand, Hosmer Soft VO hand, RSL Steeper VO hand, Otto Bock VO hand). We measured the pinch forces, activation forces, cable displacements, mass, and opening span and calculated the work and hysteresis. We compared the results with data from 1987. Hooks required lower activation forces and delivered higher pinch forces than hands. The activation forces of several devices were very high. The pinch forces of all tested hands were too low. The Hosmer model 5XA hook with three bands was the best tested hook. The Hosmer Sierra VO hand was the best tested hand. We found no improvements in VO devices compared with the data from 1987.

  19. Understanding plasma facing surfaces in magnetic fusion devices

    Science.gov (United States)

    Skinner, C. H.; Capece, A. M.; Koel, B. E.; Roszell, J. P.

    2013-09-01

    The plasma-material interface is recognized to be the most critical challenge in the realization of fusion energy. Liquid metals offer a self-healing, renewable interface that bypasses present issues with solid, neutron-damaged materials such as tungsten. Lithium in particular has dramatically improved plasma performance in many tokamaks through a reduction of hydrogen recycling. However the detailed chemical composition and properties of the top few nm that interact with the plasma are often obscure. Surface analysis has proven to be a key tool in semiconductor processing and a new laboratory has been established at PPPL to apply surface science techniques to plasma facing materials. We have shown that lithiated PFC surfaces in tokamaks will likely be oxidized during the intershot interval. Present work is focused on deuterium uptake of solid and liquid metals for plasma density control and sub-micron scale wetting of liquid metals on their substrates. The long-term goal is to provide a material database for designing liquid metal plasma facing components for tokamaks such as National Spherical Torus Experiment-Upgrade (NSTX-U) and Fusion Nuclear Science Facility-ST (FNSF-ST). Support was provided through DOE-PPPL Contract Number is DE-AC02-09CH11466.

  20. Evidence of nuclear fusion neutrons in an extremely small plasma focus device operating at 0.1 Joules

    Science.gov (United States)

    Soto, Leopoldo; Pavéz, Cristián; Moreno, José; Altamirano, Luis; Huerta, Luis; Barbaglia, Mario; Clausse, Alejandro; Mayer, Roberto E.

    2017-08-01

    We report on D-D fusion neutron emission in a plasma device with an energy input of only 0.1 J, within a range where fusion events have been considered very improbable. The results presented here are the consequence of scaling rules we have derived, thus being the key point to assure the same energy density plasma in smaller devices than in large machines. The Nanofocus (NF)—our device—was designed and constructed at the P4 Lab of the Chilean Nuclear Energy Commission. Two sets of independent measurements, with different instrumentation, were made at two laboratories, in Chile and Argentina. The neutron events observed are 20σ greater than the background. The NF plasma is produced from a pulsed electrical discharge using a submillimetric anode, in a deuterium atmosphere, showing empirically that it is, in fact, possible to heat and compress the plasma. The strong evidence presented here stretches the limits beyond what was expected. A thorough understanding of this could possibly tell us where the theoretical limits actually lie, beyond conjectures. Notwithstanding, a window is thus open for low cost endeavours for basic fusion research. In addition, the development of small, portable, safe nonradioactive neutron sources becomes a feasible issue.

  1. Characterisation of a micro-plasma device sensor using electrical measurements and emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mariotti, D

    2002-04-01

    This thesis reports on research undertaken on the characterisation of a micro-plasma device to be used for gas analysis by mean of plasma emission spectroscopy. The work covers aspects related to the micro-plasma electrical and optical emission parameters, and their importance for the utilisation of the micro-plasma device in gas analysis. Experimental results have been used to analyse the fundamental micro-plasma processes and to develop a model, which could provide additional information. This dissertation contains a general literature review of topics related to plasma physics, plasma emission spectroscopy, gas analysis (chemical analysis and artificial olfaction) and other micro-plasma applications. Experimental work focuses on two main areas: electrical measurements and emission measurements. Firstly, electrical measurements are taken and interpretations are given. Where necessary, new theoretical treatments are suggested in order to describe better the physical phenomena. Plasma emission has been considered under different working conditions. This allowed the characterisation of the micro-plasma emission and also a better understanding of the micro-plasma processes. On the basis of the experimental data obtained and other assumptions a model has been developed. A computer simulation based on this model provided additional useful information on the micro- plasma behaviour. The first fundamental implication of this new research is the peculiar behaviour of the micro-plasma. This micro-plasma exhibited deviations from Paschen law and strong dependency on cathode material, which contributed to the formation of a low current stable regime. These results have been followed by physical interpretations and theoretical descriptions. The second implication is the establishment of the boundaries and of the influencing parameters for plasma emission spectroscopy as an analytical tool in this particular micro-plasma. From the applied perspective this study has shown that

  2. A plasma source driven predator-prey like mechanism as a potential cause of spiraling intermittencies in linear plasma devices

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, D. [Research Center Jülich GmbH, Institute for Energy and Climate Research—Plasma Physics, D-52425 Jülich (Germany); Ohno, N. [Department of Energy Engineering and Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Tanaka, H. [National Institute for Fusion Science, Toki 509-5292 (Japan); Vela, L. [Physics Department, Universidad Carlos III de Madrid, Avda de la Universidad 30, 28911-Leganés, Madrid (Spain)

    2014-03-15

    Three-dimensional global drift fluid simulations are carried out to analyze coherent plasma structures appearing in the NAGDIS-II linear device (nagoya divertor plasma Simulator-II). The numerical simulations reproduce several features of the intermittent spiraling structures observed, for instance, statistical properties, rotation frequency, and the frequency of plasma expulsion. The detailed inspection of the three-dimensional plasma dynamics allows to identify the key mechanism behind the formation of these intermittent events. The resistive coupling between electron pressure and parallel electric field in the plasma source region gives rise to a quasilinear predator-prey like dynamics where the axisymmetric mode represents the prey and the spiraling structure with low azimuthal mode number represents the predator. This interpretation is confirmed by a reduced one-dimensional quasilinear model derived on the basis of the findings in the full three-dimensional simulations. The dominant dynamics reveals certain similarities to the classical Lotka-Volterra cycle.

  3. A plasma source driven predator-prey like mechanism as a potential cause of spiraling intermittencies in linear plasma devices

    Science.gov (United States)

    Reiser, D.; Ohno, N.; Tanaka, H.; Vela, L.

    2014-03-01

    Three-dimensional global drift fluid simulations are carried out to analyze coherent plasma structures appearing in the NAGDIS-II linear device (nagoya divertor plasma Simulator-II). The numerical simulations reproduce several features of the intermittent spiraling structures observed, for instance, statistical properties, rotation frequency, and the frequency of plasma expulsion. The detailed inspection of the three-dimensional plasma dynamics allows to identify the key mechanism behind the formation of these intermittent events. The resistive coupling between electron pressure and parallel electric field in the plasma source region gives rise to a quasilinear predator-prey like dynamics where the axisymmetric mode represents the prey and the spiraling structure with low azimuthal mode number represents the predator. This interpretation is confirmed by a reduced one-dimensional quasilinear model derived on the basis of the findings in the full three-dimensional simulations. The dominant dynamics reveals certain similarities to the classical Lotka-Volterra cycle.

  4. Modeling of high-explosive driven plasma compression opening switches

    Science.gov (United States)

    Greene, A. E.; Lindemuth, I. R.; Goforth, J. H.

    The initial path of the current through a plasma compression switch is through a thin (500-nm thick) metal foil. The current explodes the foil to form the seed for the conducting plasma. The behavior of the foil at this point is the same as an exploding metal fuse for which we have a simple model. We have, therefore, chosen this model as our starting point. The fuse model assumes that the foil material is homogeneous and is characterized by a single temperature and density. The thickness of the foil is assumed to be much less than the magnetic diffusion skin depth so that the magnetic field varies linearly across the foil. For the present application we assume that the side of the foil away from the channel is fixed in space while the side by the channel is untamped. The foil/plasma will, therefore, cross the channel at the expansion velocity as the foil explodes. Equations for the electrical resistance of the foil, the magnetic fields, the motion of the foil, and the kinetic and internal energies are all solved selfconsistantly. The electrical resistivity, the pressure, and the specific energy of aluminum are taken from the Los Alamos SESAME EOS library. In the case of aluminum we have created a SESAME-style table based on the theory of More and Lee which we have modified to agree with experiment where possible.

  5. Collaborative Research: Fundamental studies of plasma control using surface embedded electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Raja, Laxminarayan L. [Univ. of Texas, Austin, TX (United States); PanneerChelvam, PremKumar [Univ. of Texas, Austin, TX (United States); Levko, Dimtry [Univ. of Texas, Austin, TX (United States)

    2016-02-26

    The proposed study will investigate the effect of active electron injection of from electrode surfaces To the best of our knowledge, no such a study has ever been attempted even though it could lead to the formation of whole new classes of plasma based devices and systems. We are motivated by recent articles and simple theory which gives strong reason to believe that embedded electronic devices can be used to exert control over the SEE coefficient of semiconductor surfaces (and maybe other surface types as well). Furthermore, the research will explore how such sub-surface electronic devices can best be used to exert control over an associated plasma.

  6. Shape reconstruction of merging spherical tokamak plasma in UTST device

    Science.gov (United States)

    Ushiki, Tomohiko; Itagaki, Masafumi; Inomoto, Michiaki

    2016-10-01

    Spherical tokamak (ST) merging method is one of the ST start-up methods which heats the plasma through magnetic reconnection. In the present study reconstruction of eddy current profile and plasma shape was performed during spherical tokamak merging only using external sensor signals by the Cauchy condition surface (CCS) method. CCS method have been implemented for JT-60 (QST), QUEST (Kyushu University), KSTAR (NFRI), RELAX (KIT), and LHD (Nifs). In this method, CCS was assumed inside each plasmas, where both flux function and its normal derivative are unknown. Effect of plasma current was replaced by the boundary condition of CCS, assuming vacuum field everywhere. Also, the nodal points for the boundary integrals of eddy current density were set using quadratic elements in order to express the complicated vacuum vessel shape. Reconstructed profiles of the eddy current and the magnetic flux were well coincided with the reference in each phase of merging process. Magnetic sensor installation plan for UTST was determined from these calculation results. This work was supported by the JSPS A3 Foresight Program ``Innovative Tokamak Plasma Startup and Current Drive in Spherical Torus''.

  7. Experimental Assessment of Plasma Transport in a 16-cm Multicusp Device

    Science.gov (United States)

    Hubble, Aimee; Foster, John

    2012-10-01

    The physics of plasma transport from the bulk plasma through the magnetic cusp to the anode remains poorly understood. A proper accounting of plasma losses to the anode is critical to accurate modeling of multicusp device performance. In this work, plasma transport in a 16-cm multicusp discharge chamber was studied. Each ring was covered with an electrically isolated electrode, which enables the direct measurement of current to each individual ring as well as the discharge chamber wall. A translatable Langmuir probe was used to obtain maps of spatially resolved plasma parameters in bulk plasma region. These maps of spatially resolved plasma density, electron temperature, and plasma potential were compared to current collection at the cusps as well as the magnetic circuit and device performance. Ring electrode measurements coupled with spatially resolved plasma parameter measurements throughout the discharge chamber allow for an assessment of plasma losses to each ring in terms of an ``effective loss area'' which, multiplied by electron current density incident on the bulk/cusp boundary, gives the correct collected current to each ring. A relationship between effective loss area and the physical loss area was determined that can be applied to a 0-D particle and energy balance model.

  8. High heat flux capabilities of the Magnum-PSI linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    De Temmerman, G., E-mail: g.c.detemmerman@differ.nl; Berg, M.A. van den; Scholten, J.; Lof, A.; Meiden, H.J. van der; Eck, H.J.N. van; Morgan, T.W.; Kruijf, T.M. de; Zeijlmans van Emmichoven, P.A.; Zielinski, J.J.

    2013-10-15

    Magnum-PSI is an advanced linear plasma device uniquely capable of producing plasma conditions similar to those expected in the divertor of ITER both steady-state and transients. The machine is designed both for fundamental studies of plasma–surface interactions under high heat and particle fluxes, and as a high-heat flux facility for the tests of plasma-facing components under realistic plasma conditions. To study the effects of transient heat loads on a plasma-facing surface, a novel pulsed plasma source system as well as a high power laser is available. In this article, we will describe the capabilities of Magnum-PSI for high-heat flux tests of plasma-facing materials.

  9. Dust particles in controlled fusion devices: morphology, observations in the plasma and influence on the plasma performance

    Science.gov (United States)

    Rubel, M.; Cecconello, M.; Malmberg, J. A.; Sergienko, G.; Biel, W.; Drake, J. R.; Hedqvist, A.; Huber, A.; Philipps, V.

    2001-08-01

    The formation and release of particle agglomerates, i.e. debris and dusty objects, from plasma facing components and the impact of such materials on plasma operation in controlled fusion devices has been studied in the Extrap T2 reversed field pinch and the TEXTOR tokamak. Several plasma diagnostic techniques, camera observations and surface analysis methods were applied for in situ and ex situ investigation. The results are discussed in terms of processes that are decisive for dust transfer: localized power deposition connected with wall locked modes causing emission of carbon granules, brittle destruction of graphite and detachment of thick flaking co-deposited layers. The consequences for large next step devices are also addressed.

  10. Opening switch research on a dense plasma focus

    Science.gov (United States)

    Gerdin, G.

    1987-02-01

    Experiments were performed to enhance power coupling to the load by placing the load electrode opposite the muzzle end of the Dense Plasma Focus plasma gun. The impaler concept, whereby the current sheath is run into a knife edge insulator, was tested in two configurations. However, the power coupled to the load was always less than one tenth that of the experiments where the load was coupled to the breach of the gun. Other load coupling schemes where the load electrode was brought near the outside of the central electrode prevented pinches (voltage surges) when placed too close and the power coupled to the load was reduced when the load electrodes were moved away. The results were not as good as those of the impaler concept. Measurements of the dynamics of the current sheath in various stages were performed and compared with theory. Generally the velocity of the current sheath falls below theoretical expectations suggesting the presence of electrode drag, a phenomenon not present in the model. During the radial collapse phase the model and the experimental estimates of dL/dt are in substantiaL agreement before pinch time but disagree afterward due to two dimensional effects not present in the theory.

  11. Waveguiding and bending modes in a plasma photonic crystal bandgap device

    Directory of Open Access Journals (Sweden)

    B. Wang

    2016-06-01

    Full Text Available Waveguiding and bending modes are investigated in a fully tunable plasma photonic crystal. The plasma device actively controls the propagation of free space electromagnetic waves in the S to X band of the microwave spectrum. An array of discharge plasma tubes form a square crystal lattice exhibiting a well-defined bandgap, with individual active switching of the plasma elements to allow for waveguiding and bending modes to be generated dynamically. We show, through simulations and experiments, the existence of transverse electric (TE mode waveguiding and bending modes.

  12. Platelet-rich plasma: updating of extraction devices

    National Research Council Canada - National Science Library

    Raquel Moreno; Marisa Gaspar Carreño; Jose María Alonso Herreros; Jose Antonio Romero Garrido; Piedad López-Sánchez

    2016-01-01

    ...: Ten devices were found: ACP®; Angel®, Cascade®, Endoret ®, GPS®, Magellan®, Minos®, Ortho-pras®, Smart-prepr® and Tricell®. However, we could found out the mechanism in detail of seven of them...

  13. Observations and implications of gap closure in plasma opening switch operation

    Science.gov (United States)

    Goyer, John R.; Kortbawi, David

    1994-09-01

    Plasma opening switches are believed to develop voltage through opening and magnetically insulating a gap formed in plasma injected between two conducting electrodes. Data will be presented to show that a relatively simple assumption about the behavior of this gap suffices to describe the overall operation of the switch. Specifically, the observed increase, then decrease, of operational voltage as a function of conduction time can be accounted for by the switch gap linearly decreasing with conduction time, while the conducted current increases. In addition to presentation of data to demonstrate this collapse, analysis is performed to couple the gap history to the voltage predicted for the switch, and to optimize this latter quantity.

  14. Functionalization of Hydrogen-free Diamond-like Carbon Films using Open-air Dielectric Barrier Discharge Atmospheric Plasma Treatments

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Instituto de Materiales de Madrid, C.S.I.C., Cantoblanco, 28049 Madrid, Spain; Instituto de Quimica-Fisica" Rocasolano" C.S.I.C., 28006 Madrid, Spain; Mahasarakham University, Mahasarakham 44150, Thailand; CASTI, CNR-INFM Regional Laboratory, L' Aquila 67100, Italy; SUNY Upstate Medical University, Syracuse, NY 13210, USA; Endrino, Jose; Endrino, J. L.; Marco, J. F.; Poolcharuansin, P.; Phani, A.R.; Allen, M.; Albella, J. M.; Anders, A.

    2007-12-28

    A dielectric barrier discharge (DBD) technique has been employed to produce uniform atmospheric plasmas of He and N2 gas mixtures in open air in order to functionalize the surface of filtered-arc deposited hydrogen-free diamond-like carbon (DLC) films. XPS measurements were carried out on both untreated and He/N2 DBD plasma treated DLC surfaces. Chemical states of the C 1s and N 1s peaks were collected and used to characterize the surface bonds. Contact angle measurements were also used to record the short- and long-term variations in wettability of treated and untreated DLC. In addition, cell viability tests were performed to determine the influence of various He/N2 atmospheric plasma treatments on the attachment of osteoblast MC3T3 cells. Current evidence shows the feasibility of atmospheric plasmas in producing long-lasting variations in the surface bonding and surface energy of hydrogen-free DLC and consequently the potential for this technique in the functionalization of DLC coated devices.

  15. Temporal evolution of electron beam generated Argon plasma in pasotron device

    Science.gov (United States)

    Khandelwal, Neha; Pal, U. N.; Prakash, Ram; Choyal, Y.

    2016-10-01

    The plasma- assisted slow wave oscillator (PASOTRON) is a high power microwave source in which the electron beam in the interaction region is confined by the background plasma. The plasma is generated by impact ionization of background gas with the electron beam. A model has been developed for temporal evolution of Argon plasma in pasotron device. In this model, we consider electron beam of energy E interacting with Argon gas. The resulting ionization creates quasi neutral argon plasma composed of argon Ar atoms, singly ionized ions Ar+1and electrons having energy from 0 to E. Electron impact excitation, ionization, radiative decay, radiative recombination and three body recombination processes are considered in this model. Population of ground and excited states of argon atom, ground state of argon ion as well as the population of electron energy groups is calculated by solving time dependent rate equations. Temporal evolution of electron beam generated plasma is given.

  16. An open-source platform to study uniaxial stress effects on nanoscale devices

    Science.gov (United States)

    Signorello, G.; Schraff, M.; Zellekens, P.; Drechsler, U.; Bürge, M.; Steinauer, H. R.; Heller, R.; Tschudy, M.; Riel, H.

    2017-05-01

    We present an automatic measurement platform that enables the characterization of nanodevices by electrical transport and optical spectroscopy as a function of the uniaxial stress. We provide insights into and detailed descriptions of the mechanical device, the substrate design and fabrication, and the instrument control software, which is provided under open-source license. The capability of the platform is demonstrated by characterizing the piezo-resistance of an InAs nanowire device using a combination of electrical transport and Raman spectroscopy. The advantages of this measurement platform are highlighted by comparison with state-of-the-art piezo-resistance measurements in InAs nanowires. We envision that the systematic application of this methodology will provide new insights into the physics of nanoscale devices and novel materials for electronics, and thus contribute to the assessment of the potential of strain as a technology booster for nanoscale electronics.

  17. Automated System of Study Nonlinear Processes in Electro-vacuum Devices with Open Resonant Periodic Structures

    Directory of Open Access Journals (Sweden)

    G.S. Vorobyov

    2014-04-01

    Full Text Available The article describes the experimental equipment and the results of investigations of nonlinear processes occurring during the excitation of electromagnetic oscillations in the resonant electron beam devices such as an orotron-generator of diffraction radiation. These devices are finding wide application in physics and microwave technology, now. A technique for experimental research, which bases on the using of the universal electro vacuum equipment diffraction radiation analyzer and the microprocessor system for collecting and processing data. The experimental investigations results of the energy and frequency characteristics for the most common modes of the excitation oscillations in the open resonant systems such as an orotron. The implementations on the optimum modes for the oscillations excitation in such devices were recommended.

  18. The MaPLE device of Saha Institute of Nuclear Physics: construction and its plasma aspects.

    Science.gov (United States)

    Pal, Rabindranath; Biswas, Subir; Basu, Subhasis; Chattopadhyay, Monobir; Basu, Debjyoti; Chaudhuri, Manis; Chowdhuri, Manis

    2010-07-01

    The Magnetized Plasma Linear Experimental (MaPLE) device is a low cost laboratory plasma device at Saha Institute of Nuclear Physics fabricated in-house with the primary aim of studying basic plasma physics phenomena such as plasma instabilities, wave propagation, and their nonlinear behavior in magnetized plasma regime in a controlled manner. The machine is specially designed to be a versatile laboratory device that can provide a number of magnetic and electric scenario to facilitate such studies. A total of 36 number of 20-turn magnet coils, designed such as to allow easy handling, is capable of producing a uniform, dc magnetic field of about 0.35 T inside the plasma chamber of diameter 0.30 m. Support structure of the coils is planned in an innovative way facilitating straightforward fabrication and easy positioning of the coils. Further special feature lies in the arrangement of the spacers between the coils that can be maneuvered rather easily to create different magnetic configurations. Various methods of plasma production can be suitably utilized according to the experimental needs at either end of the vacuum vessel. In the present paper, characteristics of a steady state plasma generated by electron cyclotron resonance method using 2.45 GHz microwave power are presented. Scans using simple probe drives revealed that a uniform and long plasma column having electron density approximately 3-5x10(10) cm(-3) and temperature approximately 7-10 eV, is formed in the center of the plasma chamber which is suitable for wave launching experiments.

  19. Modeling a short cold cathode DC discharge device with controllable plasma parameters

    Science.gov (United States)

    Kudryavtsev, Anatoly; Adams, Steven; Demidov, Vladimir; Bogdanov, Yevgeny

    2009-11-01

    A short (without positive column) DC gas-discharge device with a cold cathode has been modeled. The device consists of the plane disk-shaped cathode and anode while the inter-electrode gap is bounded by a cylindrical wall. The cathode and anode are each 2.5 cm in diameter, and the inter-electrode gap is 12 mm. The wall is made of conducting parts divided by an insulator. The modeling has been performed for argon plasma at 1 Torr pressure. It is demonstrated in the model that spatial distributions of electron density and temperature and argon metastable atom density depend on the DC voltage applied to different conducting parts of the wall. Applied voltage can trap within the device volume energetic electrons arising from atomic and molecular processes in the plasma. This leads to a modification in the heating of slow electrons by energetic electrons and as a result modifies the controlling plasma parameters.

  20. OC ToGo: bed site image integration into OpenClinica with mobile devices

    Science.gov (United States)

    Haak, Daniel; Gehlen, Johan; Jonas, Stephan; Deserno, Thomas M.

    2014-03-01

    Imaging and image-based measurements nowadays play an essential role in controlled clinical trials, but electronic data capture (EDC) systems insufficiently support integration of captured images by mobile devices (e.g. smartphones and tablets). The web application OpenClinica has established as one of the world's leading EDC systems and is used to collect, manage and store data of clinical trials in electronic case report forms (eCRFs). In this paper, we present a mobile application for instantaneous integration of images into OpenClinica directly during examination on patient's bed site. The communication between the Android application and OpenClinica is based on the simple object access protocol (SOAP) and representational state transfer (REST) web services for metadata, and secure file transfer protocol (SFTP) for image transfer, respectively. OpenClinica's web services are used to query context information (e.g. existing studies, events and subjects) and to import data into the eCRF, as well as export of eCRF metadata and structural information. A stable image transfer is ensured and progress information (e.g. remaining time) visualized to the user. The workflow is demonstrated for a European multi-center registry, where patients with calciphylaxis disease are included. Our approach improves the EDC workflow, saves time, and reduces costs. Furthermore, data privacy is enhanced, since storage of private health data on the imaging devices becomes obsolete.

  1. Surface modifications of fusion reactor relevant materials on exposure to fusion grade plasma in plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Niranjan, Ram, E-mail: niranjan@barc.gov.in [Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Rout, R.K.; Srivastava, R. [Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Chakravarthy, Y. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Mishra, P. [Materials Processing Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kaushik, T.C.; Gupta, Satish C. [Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2015-11-15

    Graphical abstract: - Highlights: • Exposure of materials (W, Ni, SS, Mo and Cu) to fusion plasma in a plasma focus device. • The erosion and the formations of blisters, pores, craters, micro-cracks after irradiation. • The structural phase transformation in the SS sample after irradiation. • The surface layer alloying of the samples with the plasma focus anode material. - Abstract: An 11.5 kJ plasma focus (PF) device was used here to irradiate materials with fusion grade plasma. The surface modifications of different materials (W, Ni, stainless steel, Mo and Cu) were investigated using various available techniques. The prominent features observed through the scanning electron microscope on the sample surfaces were erosions, cracks, blisters and craters after irradiations. The surface roughness of the samples increased multifold after exposure as measured by the surface profilometer. The X-ray diffraction analysis indicated the changes in the microstructures and the structural phase transformation in surface layers of the samples. We observed change in volumes of austenite and ferrite phases in the stainless steel sample. The energy dispersive X-ray spectroscopic analysis suggested alloying of the surface layer of the samples with elements of the PF anode. We report here the comparative analysis of the surface damages of materials with different physical, thermal and mechanical properties. The investigations will be useful to understand the behavior of the perspective materials for future fusion reactors (either in pure form or in alloy) over the long operations.

  2. Laser induced fluorescence measurements of axial velocity, velocity shear, and parallel ion temperature profiles during the route to plasma turbulence in a linear magnetized plasma device

    Science.gov (United States)

    Chakraborty Thakur, S.; Adriany, K.; Gosselin, J. J.; McKee, J.; Scime, E. E.; Sears, S. H.; Tynan, G. R.

    2016-11-01

    We report experimental measurements of the axial plasma flow and the parallel ion temperature in a magnetized linear plasma device. We used laser induced fluorescence to measure Doppler resolved ion velocity distribution functions in argon plasma to obtain spatially resolved axial velocities and parallel ion temperatures. We also show changes in the parallel velocity profiles during the transition from resistive drift wave dominated plasma to a state of weak turbulence driven by multiple plasma instabilities.

  3. MHD Instabilities and Their Effects on Plasma Confinement in Large Helical Device Plasmas with Intense Neutral Beam Injection

    Institute of Scientific and Technical Information of China (English)

    K. Toi; K. Narihara; K. Tanaka; T. Tokuzawa; H. Yamada; Q. Yang; LHD experimental group; S. Ohdachi; S. Yamamoto; S. Sakakibara; K. Y. Watanabe; N. Nakajima; X. Ding; J. Li; S. Morita

    2004-01-01

    MHD stability of the Large Helical Device (LHD) plasmas produced with intense neutral beam injection is experimentally studied. When the steep pressure gradient near the edge is produced through L-H transition or linear density ramp experiment, interchange-like MHD modes whose rational surface is located very close to the last closed flux surface are strongly excited in a certain discharge condition and affect the plasma transport appreciably. In NBI-heated energetic ion loss, but also trigger the formation of internal and edge transport barriers.

  4. Development of a microfluidic device for cell concentration and blood cell-plasma separation.

    Science.gov (United States)

    Maria, M Sneha; Kumar, B S; Chandra, T S; Sen, A K

    2015-12-01

    This work presents design, fabrication and test of a microfluidic device which employs Fahraeus-Lindqvist and Zweifach-Fung effects for cell concentration and blood cell-plasma separation. The device design comprises a straight main channel with a series of branched channels placed symmetrically on both sides of the main channel. The design implements constrictions before each junction (branching point) in order to direct cells that would have migrated closer to the wall (naturally or after liquid extraction at a junction) towards the centre of the main channel. Theoretical and numerical analysis are performed for design of the microchannel network to ensure that a minimum flow rate ratio (of 2.5:1, main channel-to-side channels) is maintained at each junction and predict flow rate at the plasma outlet. The dimensions and location of the constrictions were determined using numerical simulations. The effect of presence of constrictions before the junctions was demonstrated by comparing the performances of the device with and without constrictions. To demonstrate the performance of the device, initial experiments were performed with polystyrene microbeads (10 and 15 μm size) and droplets. Finally, the device was used for concentration of HL60 cells and separation of plasma and cells in diluted blood samples. The cell concentration and blood-plasma purification efficiency was quantified using Haemocytometer and Fluorescence-Activated Cell Sorter (FACS). A seven-fold cell concentration was obtained with HL60 cells and a purification efficiency of 70 % and plasma recovery of 80 % was observed for diluted (1:20) blood sample. FACS was used to identify cell lysis and the cell viability was checked using Trypan Blue test which showed that more than 99 % cells are alive indicating the suitability of the device for practical use. The proposed device has potential to be used as a sample preparation module in lab on chip based diagnostic platforms.

  5. Statistical characterization of the reproducibility of neutron emission of small plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Tarifeno-Saldivia, Ariel; Soto, Leopoldo [Comision Chilena de Energia Nuclear (CCHEN), Casilla 188-D, Santiago (Chile); Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile) and Departamento de Ciencias Fisicas, Universidad Andres Bello, Republica 220, Santiago (Chile)

    2012-09-15

    The purpose of this work is to discuss the techniques related to the detection of fast pulsed neutrons produced in plasma focus (PF) devices, the statistical analysis of the corresponding data, and the methodologies for evaluation of the device performance in low emission neutron sources. A general mathematical framework is presented for the assessment of the reproducibility of the neutron emission of small PF devices given the shot-to-shot distribution and detector efficiency. The effect on the reproducibility in case of using two independent detectors is also discussed. The analysis is applied to the neutron emission of the plasma focus device PF-50J operating in repetitive mode (0.1-0.5 Hz and 65 J bank energy).

  6. Neutron and Ion Beams Emitted from Plasma Focus (112.5 J) Device

    Science.gov (United States)

    El-Aragi M., G.

    2010-02-01

    Preliminary results of recent experiments performed within the Mather-type 112.5 J plasma focus device are presented. The ion beams from the focus device operated with deuterium filling at 1 mbar were registered using CR-39 solid state nuclear track detectors (SSNTD) and a Faraday cup detector for time-resolved measurements. The time-resolved neutron emission from the focus region measurements was detected with a photomultiplier tube (IP-28) optically coupled with a plastic scintillator NE 102.

  7. Integrated separation of blood plasma from whole blood for microfluidic paper-based analytical devices.

    Science.gov (United States)

    Yang, Xiaoxi; Forouzan, Omid; Brown, Theodore P; Shevkoplyas, Sergey S

    2012-01-21

    Many diagnostic tests in a conventional clinical laboratory are performed on blood plasma because changes in its composition often reflect the current status of pathological processes throughout the body. Recently, a significant research effort has been invested into the development of microfluidic paper-based analytical devices (μPADs) implementing these conventional laboratory tests for point-of-care diagnostics in resource-limited settings. This paper describes the use of red blood cell (RBC) agglutination for separating plasma from finger-prick volumes of whole blood directly in paper, and demonstrates the utility of this approach by integrating plasma separation and a colorimetric assay in a single μPAD. The μPAD was fabricated by printing its pattern onto chromatography paper with a solid ink (wax) printer and melting the ink to create hydrophobic barriers spanning through the entire thickness of the paper substrate. The μPAD was functionalized by spotting agglutinating antibodies onto the plasma separation zone in the center and the reagents of the colorimetric assay onto the test readout zones on the periphery of the device. To operate the μPAD, a drop of whole blood was placed directly onto the plasma separation zone of the device. RBCs in the whole blood sample agglutinated and remained in the central zone, while separated plasma wicked through the paper substrate into the test readout zones where analyte in plasma reacted with the reagents of the colorimetric assay to produce a visible color change. The color change was digitized with a portable scanner and converted to concentration values using a calibration curve. The purity and yield of separated plasma was sufficient for successful operation of the μPAD. This approach to plasma separation based on RBC agglutination will be particularly useful for designing fully integrated μPADs operating directly on small samples of whole blood.

  8. Innovation in the development of plasma propulsion devices in Israel

    Science.gov (United States)

    Lev, Dan R.

    2017-04-01

    In this paper we review plasma propulsion development approach which focuses on innovation. We then bring the example of the state of Israel in general, and Rafael in particular, and show how it has adopted an innovative approach to develop a low power Hall thruster and a low current cathode. To present one special test-case of innovation we elaborate upon the development process of a heaterless hollow cathode that was developed at Rafael. In particular, by presenting the cathode characterization and wear test results we demonstrate that the heaterless cathode developed has a sufficiently wide operational range and may operate continuously for 1,500 hours without any measurable degradation in performance.

  9. Theoretical and computational studies of magnetic insulation and other plasma-opening-switch phenomena

    Science.gov (United States)

    Lindeman, Erick L., Jr.

    1989-11-01

    The following topics are discussed: electron trajectories and magnetic insulation; blade-load simulation studies; azimuthal asymmetries; MAGIC simulation studies of a segmented plasma opening switch; PBFA II calculations with different spatial resolution; and analytic solution of the electron current layer in the magnetic front.

  10. Experimental Investigation of Turbulent-driven Sheared Parallel Flows in the CSDX Plasma Device

    Science.gov (United States)

    Tynan, George; Hong, Rongjie; Li, Jiacong; Thakur, Saikat; Diamond, Patrick

    2016-10-01

    Parallel velocity and its radial shear is a key element for both accessing improved confinement regimes and controlling the impurity transport in tokamak devices. In this study, the development of radially sheared parallel plasma flows in plasmas without magnetic shear is investigated using laser induced fluorescence, multi-tip Langmuir and Mach probes in the CSDX helicon linear plasma device. Results show that a mean parallel velocity shear grows as the radial gradient of plasma density increased. The sheared flow onset corresponds to the onset of a finite parallel Reynolds stress that acts to reinforce the flow. As a result, the mean parallel flow gains energy from the turbulence that, in turn, is driven by the density gradient. This results in a flow away from the plasma source in the central region of the plasma and a reverse flow in far-peripheral region of the plasma column. The results motivate a model of negative viscosity induced by the turbulent stress which may help explain the origin of intrinsic parallel flow in systems without magnetic shear.

  11. An Electrothermal Plasma Source Developed for Simulation of Transient Heat Loads in Future Large Fusion Devices

    Science.gov (United States)

    Gebhart, Trey; Baylor, Larry; Winfrey, Leigh

    2016-10-01

    The realization of fusion energy requires materials that can withstand high heat and particle fluxes at the plasma material interface. In this work, an electrothermal (ET) plasma source has been designed as a possible transient heat flux source for a linear plasma material interaction device. An ET plasma source operates in the ablative arc regime, which is driven by a DC capacitive discharge. The current travels through the 4mm bore of a boron nitride liner and subsequently ablates and ionizes the liner material. This results in a high density plasma with a large unidirectional bulk flow out of the source exit. The pulse length for the ET source has been optimized using a pulse forming network to have a duration of 1ms at full-width half maximum. The peak currents and maximum source energies seen in this system are 2kA and 5kJ. The goal of this work is to show that the ET source produces electron densities and heat fluxes that are comparable to transient events in future large magnetic confinement fusion devices. Heat flux, plasma temperature, and plasma density were determined for each test shot using infrared imaging and optical spectroscopy techniques. This work will compare the ET source output (heat flux, temperature, and density) with and without an applied magnetic field. Research sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy.

  12. Turbulent jet flow generated downstream of a low temperature dielectric barrier atmospheric pressure plasma device

    Science.gov (United States)

    Whalley, Richard D.; Walsh, James L.

    2016-08-01

    Flowing low temperature atmospheric pressure plasma devices have been used in many technological applications ranging from energy efficient combustion through to wound healing and cancer therapy. The generation of the plasma causes a sudden onset of turbulence in the inhomogeneous axisymmetric jet flow downstream of the plasma plume. The mean turbulent velocity fields are shown to be self-similar and independent of the applied voltage used to generate the plasma. It is proposed that the production of turbulence is related to a combination of the small-amplitude plasma induced body forces and gas heating causing perturbations in the unstable shear layers at the jet exit which grow as they move downstream, creating turbulence.

  13. Turbulent jet flow generated downstream of a low temperature dielectric barrier atmospheric pressure plasma device.

    Science.gov (United States)

    Whalley, Richard D; Walsh, James L

    2016-08-26

    Flowing low temperature atmospheric pressure plasma devices have been used in many technological applications ranging from energy efficient combustion through to wound healing and cancer therapy. The generation of the plasma causes a sudden onset of turbulence in the inhomogeneous axisymmetric jet flow downstream of the plasma plume. The mean turbulent velocity fields are shown to be self-similar and independent of the applied voltage used to generate the plasma. It is proposed that the production of turbulence is related to a combination of the small-amplitude plasma induced body forces and gas heating causing perturbations in the unstable shear layers at the jet exit which grow as they move downstream, creating turbulence.

  14. Plasma density evolution in plasma opening switch obtained by a time-resolved sensitive He-Ne interferometer

    Science.gov (United States)

    Chen, Lin; Ren, Jing; Guo, Fan; Zhou, LiangJi; Li, Ye; He, An; Jiang, Wei

    2014-03-01

    To understand the formation process of vacuum gap in coaxial microsecond conduction time plasma opening switch (POS), we have made measurements of the line-integrated plasma density during switch operation using a time-resolved sensitive He-Ne interferometer. The conduction current and conduction time in experiments are about 120 kA and 1 μs, respectively. As a result, more than 85% of conduction current has been transferred to an inductive load with rise time of 130 ns. The radial dependence of the density is measured by changing the radial location of the line-of-sight for shots with the same nominal POS parameters. During the conduction phase, the line-integrated plasma density in POS increases at all radial locations over the gun-only case by further ionization of material injected from the guns. The current conduction is observed to cause a radial redistribution of the switch plasma. A vacuum gap forms rapidly in the plasma at 5.5 mm from the center conductor, which is consistent with the location where magnetic pressure is the largest, allowing current to be transferred from the POS to the load.

  15. Modeling Plasmas with Strong Anisotropy, Neutral Fluid Effects, and Open Boundaries

    Science.gov (United States)

    Meier, Eric T.

    Three computational plasma science topics are addressed in this research: the challenge of modeling strongly anisotropic thermal conduction, capturing neutral fluid effects in collisional plasmas, and modeling open boundaries in dissipative plasmas. The research efforts on these three topics contribute to a common objective: the improvement and extension of existing magnetohydrodynamic modeling capability. Modeling magnetically confined fusion-related plasmas is the focus of the research, but broader relevance is recognized and discussed. Code development is central to this work, and has been carried out within the flexible physics framework of the highly parallel HiFi implicit spectral element code. In magnetic plasma confinement, heat conduction perpendicular to the magnetic field is extremely slow compared to conduction parallel to the field. The anisotropy in heat conduction can be many orders of magnitude, and the inaccuracy of low-order representations can allow parallel heat transport to "leak" into the perpendicular direction, resulting in numerical perpendicular transport. If the computational grid is aligned to the magnetic field, this numerical error can be eliminated, even for low-order representations. However, grid alignment is possible only in idealized problems. In realistic applications, magnetic topology is chaotic. A general approach for accurately modeling the extreme anisotropy of fusion plasmas is to use high-order representations which do not require grid alignment for sufficient resolution. This research provides a comprehensive assessment of spectral element representation of anisotropy, in terms of dependence of accuracy on grid alignment, polynomial degree, and grid cell size, and gives results for two- and three-dimensional cases. Truncating large physical domains to concentrate computational resources is often necessary or desirable in simulating natural and man-made plasmas. A novel open boundary condition (BC) treatment for such

  16. [Platelet-rich plasma: updating of extraction devices].

    Science.gov (United States)

    Moreno, Raquel; Gaspar Carreño, Marisa; Alonso Herreros, Jose María; Romero Garrido, Jose Antonio; López-Sánchez, Piedad

    2016-09-01

    Objetivo: Describir los dispositivos para la obtención de Plasma Rico en Plaquetas (PRP) mediante la revisión de los productos existentes en España, teniendo en consideración las aportaciones de la Agencia Española de Medicamentos y Productos Sanitarios (AEMPS) y los grupos de trabajo de Productos Sanitarios (GPS), Farmacotecnia y Hemoderivados de la Sociedad Española de Farmacia Hospitalaria (SEFH). Método: Se realizaron tres búsquedas independientes sobre dispositivos de fraccionamiento de plasma. Se contactó con los proveedores y se estableció una reunión con cada uno de ellos. Se revisaron las características de cada dispositivo mediante una demostración del proceso de fraccionamiento virtual y se elaboró una tabla de comparación de kits. Los dispositivos se clasificaron como Técnica cerrada y Técnica abierta de acuerdo al informe del comité técnico de inspección de la AEMPS. Resultados: Se localizaron diez dispositivos: ACP®; Angel®, Cascade®, Endoret®, GPS®, Magellan®, Minos®, Ortho-pras®, Smart-prepr® y Tricell®, pudiendo conocer de forma detallada el funcionamiento en siete de ellos. Sin embargo, de Cascade ®, Magellan® y Smart-prepr® no se consiguió información suficiente. Conclusión: La revisión permitió conocer los principales dispositivos de extracción de PRP disponibles con marcado CE y sus características diferenciales; sin embargo, para garantizar la calidad del producto final es crucial poner atención en el propio proceso de extracción y administración del PRP. El Servicio de Farmacia debe implicarse en su selección por la estrecha relación que mantiene con la calidad del medicamento elaborado. El trabajo conjunto con la AEMPS permitirá definir de forma más específica el proceso correcto de elaboración.

  17. A comprehensive study of electrostatic turbulence and transport in the laboratory basic plasma device TORPEX

    Science.gov (United States)

    Furno, I.; Fasoli, A.; Avino, F.; Bovet, A.; Gustafson, K.; Iraji, D.; Labit, B.; Loizu, J.; Ricci, P.; Theiler, C.

    2012-04-01

    TORPEX is a toroidal device located at the CRPP-EPFL in Lausanne. In TORPEX, a vertical magnetic field superposed on a toroidal field creates helicoidal field lines with both ends terminating on the torus vessel. The turbulence driven by magnetic curvature and plasma gradients causes plasma transport in the radial direction while at the same time plasma is progressively lost along the field lines. The relatively simple magnetic geometry and diagnostic access of the TORPEX configuration facilitate the experimental study of low frequency instabilities and related turbulent transport, and make an accurate comparison between simulations and experiments possible. We first present a detailed investigation of electrostatic interchange turbulence, associated structures and their effect on plasma using high-resolution diagnostics of plasma parameters and wave fields throughout the whole device cross-section, fluid models and numerical simulations. Interchange modes nonlinearly develop blobs, radially propagating filaments of enhanced plasma pressure. Blob velocities and sizes are obtained from probe measurements using pattern recognition and are described by an analytical expression that includes ion polarization currents, parallel sheath currents and ion-neutral collisions. Then, we describe recent advances of a non-perturbative Li 6+ miniaturized ion source and a detector for the investigation of the interaction between supra thermal ions and interchange-driven turbulence. We present first measurements of the spatial and energy space distribution of the fast ion beam in different plasma scenarios, in which the plasma turbulence is fully characterized. The experiments are interpreted using two-dimensional fluid simulations describing the low-frequency interchange turbulence, taking into account the plasma source and plasma losses at the torus vessel. By treating fast ions as test particles, we integrate their equations of motion in the simulated electromagnetic fields, and

  18. A portable image overlay projection device for computer-aided open liver surgery.

    Science.gov (United States)

    Gavaghan, Kate A; Peterhans, Matthias; Oliveira-Santos, Thiago; Weber, Stefan

    2011-06-01

    Image overlay projection is a form of augmented reality that allows surgeons to view underlying anatomical structures directly on the patient surface. It improves intuitiveness of computer-aided surgery by removing the need for sight diversion between the patient and a display screen and has been reported to assist in 3-D understanding of anatomical structures and the identification of target and critical structures. Challenges in the development of image overlay technologies for surgery remain in the projection setup. Calibration, patient registration, view direction, and projection obstruction remain unsolved limitations to image overlay techniques. In this paper, we propose a novel, portable, and handheld-navigated image overlay device based on miniature laser projection technology that allows images of 3-D patient-specific models to be projected directly onto the organ surface intraoperatively without the need for intrusive hardware around the surgical site. The device can be integrated into a navigation system, thereby exploiting existing patient registration and model generation solutions. The position of the device is tracked by the navigation system's position sensor and used to project geometrically correct images from any position within the workspace of the navigation system. The projector was calibrated using modified camera calibration techniques and images for projection are rendered using a virtual camera defined by the projectors extrinsic parameters. Verification of the device's projection accuracy concluded a mean projection error of 1.3 mm. Visibility testing of the projection performed on pig liver tissue found the device suitable for the display of anatomical structures on the organ surface. The feasibility of use within the surgical workflow was assessed during open liver surgery. We show that the device could be quickly and unobtrusively deployed within the sterile environment.

  19. Study of plasma equilibrium in toroidal fusion devices using mesh-free numerical calculation method

    Science.gov (United States)

    Rasouli, C.; Abbasi Davani, F.; Rokrok, B.

    2016-08-01

    Plasma confinement using external magnetic field is one of the successful ways leading to the controlled nuclear fusion. Development and validation of the solution process for plasma equilibrium in the experimental toroidal fusion devices is the main subject of this work. Solution of the nonlinear 2D stationary problem as posed by the Grad-Shafranov equation gives quantitative information about plasma equilibrium inside the vacuum chamber of hot fusion devices. This study suggests solving plasma equilibrium equation which is essential in toroidal nuclear fusion devices, using a mesh-free method in a condition that the plasma boundary is unknown. The Grad-Shafranov equation has been solved numerically by the point interpolation collocation mesh-free method. Important features of this approach include truly mesh free, simple mathematical relationships between points and acceptable precision in comparison with the parametric results. The calculation process has been done by using the regular and irregular nodal distribution and support domains with different points. The relative error between numerical and analytical solution is discussed for several test examples such as small size Damavand tokamak, ITER-like equilibrium, NSTX-like equilibrium, and typical Spheromak.

  20. IMF Screw: An Ideal Intermaxillary Fixation Device During Open Reduction of Mandibular Fracture.

    Science.gov (United States)

    Sahoo, N K; Mohan, Ritu

    2010-06-01

    Intermaxillary fixation (IMF) is conventionally used for treatment of fractures involving maxillomandibular complex both for closed reduction and as an adjuvant to open reduction. To overcome the cumbersome procedure of tooth borne appliances cortical bone screws were introduced in the year of 1989 to achieve IMF which is essentially a bone borne appliance. In our institution we treated 45 cases of mandibular fracture both single and multiple fractures by open reduction over a period of 24 months. IMF screws were used to achieve dental occlusion in all the cases. Various advantages, disadvantages and complications are discussed. In our institutional experience we found that the IMF screws are an ideal device for temporary intermaxillary fixation for the cases having only mandibular fracture.

  1. Modeling of defect generation during plasma etching and its impact on electronic device performance—plasma-induced damage

    Science.gov (United States)

    Eriguchi, Koji

    2017-08-01

    The increasing demand for the higher performance of ultra-large-scale integration (ULSI) circuits requires the aggressive shrinkage of device feature sizes in accordance with the scaling law. Plasma processing plays an important role in achieving fine patterns with anisotropic features in metal-oxide-semiconductor field-effect transistors (MOSFETs). This article comprehensively addresses the negative aspects of plasma processing, i.e. plasma process-induced damage, in particular, the defect creation induced by ion bombardment in Si substrates during plasma etching. The ion bombardment damage forms a surface modified region and creates localized defect structures. Modeling and characterization techniques of the ion bombardment damage in Si substrates are overviewed. The thickness of the modified region, i.e. the damaged layer, is modeled by a modified range theory and the density of defects is characterized by photoreflectance spectroscopy (PRS) and the capacitance-voltage technique. The effects of plasma-induced damage (PID) on MOSFET performance are presented. In addition, some of the emerging topics—the enhanced parameter variability in ULSI circuits and recovery of the damage—are discussed as future perspectives.

  2. Capillary flow-driven microfluidic device with wettability gradient and sedimentation effects for blood plasma separation

    Science.gov (United States)

    Maria, M. Sneha; Rakesh, P. E.; Chandra, T. S.; Sen, A. K.

    2017-01-01

    We report a capillary flow-driven microfluidic device for blood-plasma separation that comprises a cylindrical well between a pair of bottom and top channels. Exposure of the well to oxygen-plasma creates wettability gradient on its inner surface with its ends hydrophilic and middle portion hydrophobic. Due to capillary action, sample blood self-infuses into bottom channel and rises up the well. Separation of plasma occurs at the hydrophobic patch due to formation of a ‘self-built-in filter’ and sedimentation. Capillary velocity is predicted using a model and validated using experimental data. Sedimentation of RBCs is explained using modified Steinour’s model and correlation between settling velocity and liquid concentration is found. Variation of contact angle on inner surface of the well is characterized and effects of well diameter and height and dilution ratio on plasma separation rate are investigated. With a well of 1.0 mm diameter and 4.0 mm height, 2.0 μl of plasma was obtained (from <10 μl whole blood) in 15 min with a purification efficiency of 99.9%. Detection of glucose was demonstrated with the plasma obtained. Wetting property of channels was maintained by storing in DI water under vacuum and performance of the device was found to be unaffected over three weeks. PMID:28256564

  3. Capillary flow-driven microfluidic device with wettability gradient and sedimentation effects for blood plasma separation

    Science.gov (United States)

    Maria, M. Sneha; Rakesh, P. E.; Chandra, T. S.; Sen, A. K.

    2017-03-01

    We report a capillary flow-driven microfluidic device for blood-plasma separation that comprises a cylindrical well between a pair of bottom and top channels. Exposure of the well to oxygen-plasma creates wettability gradient on its inner surface with its ends hydrophilic and middle portion hydrophobic. Due to capillary action, sample blood self-infuses into bottom channel and rises up the well. Separation of plasma occurs at the hydrophobic patch due to formation of a ‘self-built-in filter’ and sedimentation. Capillary velocity is predicted using a model and validated using experimental data. Sedimentation of RBCs is explained using modified Steinour’s model and correlation between settling velocity and liquid concentration is found. Variation of contact angle on inner surface of the well is characterized and effects of well diameter and height and dilution ratio on plasma separation rate are investigated. With a well of 1.0 mm diameter and 4.0 mm height, 2.0 μl of plasma was obtained (from purification efficiency of 99.9%. Detection of glucose was demonstrated with the plasma obtained. Wetting property of channels was maintained by storing in DI water under vacuum and performance of the device was found to be unaffected over three weeks.

  4. Analysis of the interaction of deuterium plasmas with tungsten in the Fuego-Nuevo II device

    Science.gov (United States)

    Ramos, Gonzalo; Castillo, Fermín; Nieto, Martín; Martínez, Marco; Rangel, José; Herrera-Velázquez, Julio

    2012-10-01

    Tungsten is one of the main candidate materials for plasma-facing components in future fusion power plants. The Fuego-Nuevo II, a plasma focus device, which can produce dense magnetized helium and deuterium plasmas, has been adapted to address plasma-facing materials questions. In this paper we present results of tungsten targets exposed to deuterium plasmas in the Fuego Nuevo II device, using different experimental conditions. The plasma generated and accelerated in the coaxial gun is expected to have, before the pinch, energies of the order of hundreds eV and velocities of the order of 40,000 m s-1. At the pinch, the ions are reported to have energies of the order of 1.5 keV at most. The samples, analysed with a scanning electron microscope (SEM) in cross section show a damage profile to depths of the order of 580 nm, which are larger than those expected for ions with 1.5 keV, and may be evidence of ion acceleration. An analysis with the SRIM (Stopping Range of Ions in Matter) package calculations is shown.

  5. Some physics and chemistry of Coblation® electrosurgical plasma devices

    Science.gov (United States)

    Stalder, Kenneth R.; Ryan, Thomas P.; Woloszko, Jean

    2013-02-01

    Electrosurgical devices employing plasmas to ablate, cut and otherwise treat tissues have been in widespread use for decades. Following d'Arsonval's 19th century work on the neuromuscular response from high-frequency excitation of tissue, Doyen treated skin blemishes with a spark-gap generator in 1909. In the late 1920's, physician Harvey Cushing and Harvard physicist William Bovie developed an electrosurgical device and power source that eventually became a standard of care for cutting, coagulating, desiccating, or fulgurating tissue. Beginning in the 1990's a new class of low-voltage electrosurgical devices employing electricallyconducting saline fluids were developed by ArthroCare Corp. These modern Coblation® devices are now widely used in many different surgical procedures, including those in arthroscopic surgery, otorhinolaryngology, spine surgery, urology, gynecological surgery, and others. This paper summarizes some of the research we have been doing over the last decade to elucidate the physics and chemistry underlying Coblation® electrosurgical devices. Electrical-, thermal-, fluid-, chemicaland plasma-physics all play important roles in these devices and give rise to a rich variety of observations. Experimental techniques employed include optical and mass spectroscopy, fast optical imaging, and electrical voltage and current measurements. Many of the features occur on fast time scales and small spatial scales, making laboratory measurements difficult, so coupled-physics, finite-element-modeling can also be employed to glean more information than has been acquired thus far through physical observation.

  6. A titanium hydride gun for plasma injection into the T2-reversed field pinch device

    Science.gov (United States)

    Voronin, A. V.; Hellblom, K. G.

    1999-02-01

    A study of a plasma gun (modified Bostic type) with titanium hydride electrodes has been carried out. The total number of released hydrogen atoms was in the range 1016-1018 and the maximum plasma flow velocity was 2.5×105 m s-1. The ion density near the gun edge reached 1.8×1020 m-3 and the electron temperature was around 40 eV as estimated from probe measurements. No species other than hydrogen or titanium were seen in the plasma line radiation. The plasma injector was successfully used for gas pre-ionization in the Extrap T2 reversed-field pinch device (ohmic heating toroidal experiment (OHTE)).

  7. Automation of plasma protein binding assay using rapid equilibrium dialysis device and Tecan workstation.

    Science.gov (United States)

    Ye, Zhengqi; Zetterberg, Craig; Gao, Hong

    2017-03-14

    Binding of drug molecules to plasma proteins is an important parameter in assessing drug ADME properties. Plasma protein binding (PPB) assays are routinely performed during drug discovery and development. A fully automated PPB assay was developed using rapid equilibrium dialysis (RED) device and Tecan workstation coupled to an automated incubator. The PPB assay was carried out in unsealed RED plates which allowed the assay to be fully automated. The plasma pH was maintained at 7.4 during the 6-h dialysis under 2% CO2 condition. The samples were extracted with acetonitrile and analyzed by liquid chromatography tandem mass spectrometry. The percent bound results of 10 commercial drugs in plasma protein binding were very similar between the automated and manual assays, and were comparable to literature values. The automated assay increases laboratory productivity and is applicable to high-throughput screening of drug protein binding in drug discovery.

  8. A Real-Time Web of Things Framework with Customizable Openness Considering Legacy Devices

    Science.gov (United States)

    Zhao, Shuai; Yu, Le; Cheng, Bo

    2016-01-01

    With the development of the Internet of Things (IoT), resources and applications based on it have emerged on a large scale. However, most efforts are “silo” solutions where devices and applications are tightly coupled. Infrastructures are needed to connect sensors to the Internet, open up and break the current application silos and move to a horizontal application mode. Based on the concept of Web of Things (WoT), many infrastructures have been proposed to integrate the physical world with the Web. However, issues such as no real-time guarantee, lack of fine-grained control of data, and the absence of explicit solutions for integrating heterogeneous legacy devices, hinder their widespread and practical use. To address these issues, this paper proposes a WoT resource framework that provides the infrastructures for the customizable openness and sharing of users’ data and resources under the premise of ensuring the real-time behavior of their own applications. The proposed framework is validated by actual systems and experimental evaluations. PMID:27690038

  9. A Real-Time Web of Things Framework with Customizable Openness Considering Legacy Devices

    Directory of Open Access Journals (Sweden)

    Shuai Zhao

    2016-09-01

    Full Text Available With the development of the Internet of Things (IoT, resources and applications based on it have emerged on a large scale. However, most efforts are “silo” solutions where devices and applications are tightly coupled. Infrastructures are needed to connect sensors to the Internet, open up and break the current application silos and move to a horizontal application mode. Based on the concept of Web of Things (WoT, many infrastructures have been proposed to integrate the physical world with the Web. However, issues such as no real-time guarantee, lack of fine-grained control of data, and the absence of explicit solutions for integrating heterogeneous legacy devices, hinder their widespread and practical use. To address these issues, this paper proposes a WoT resource framework that provides the infrastructures for the customizable openness and sharing of users’ data and resources under the premise of ensuring the real-time behavior of their own applications. The proposed framework is validated by actual systems and experimental evaluations.

  10. A Real-Time Web of Things Framework with Customizable Openness Considering Legacy Devices.

    Science.gov (United States)

    Zhao, Shuai; Yu, Le; Cheng, Bo

    2016-09-28

    With the development of the Internet of Things (IoT), resources and applications based on it have emerged on a large scale. However, most efforts are "silo" solutions where devices and applications are tightly coupled. Infrastructures are needed to connect sensors to the Internet, open up and break the current application silos and move to a horizontal application mode. Based on the concept of Web of Things (WoT), many infrastructures have been proposed to integrate the physical world with the Web. However, issues such as no real-time guarantee, lack of fine-grained control of data, and the absence of explicit solutions for integrating heterogeneous legacy devices, hinder their widespread and practical use. To address these issues, this paper proposes a WoT resource framework that provides the infrastructures for the customizable openness and sharing of users' data and resources under the premise of ensuring the real-time behavior of their own applications. The proposed framework is validated by actual systems and experimental evaluations.

  11. Removal of Elemental Mercury from a Gas Stream Facilitated by a Non-Thermal Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Charles Mones

    2006-12-01

    Mercury generated from anthropogenic sources presents a difficult environmental problem. In comparison to other toxic metals, mercury has a low vaporization temperature. Mercury and mercury compounds are highly toxic, and organic forms such as methyl mercury can be bio-accumulated. Exposure pathways include inhalation and transport to surface waters. Mercury poisoning can result in both acute and chronic effects. Most commonly, chronic exposure to mercury vapor affects the central nervous system and brain, resulting in neurological damage. The CRE technology employs a series of non-thermal, plasma-jet devices to provide a method for elemental mercury removal from a gas phase by targeting relevant chemical reactions. The technology couples the known chemistry of converting elemental mercury to ionic compounds by mercury-chlorine-oxygen reactions with the generation of highly reactive species in a non-thermal, atmospheric, plasma device. The generation of highly reactive metastable species in a non-thermal plasma device is well known. The introduction of plasma using a jet-injection device provides a means to contact highly reactive species with elemental mercury in a manner to overcome the kinetic and mass-transfer limitations encountered by previous researchers. To demonstrate this technology, WRI has constructed a plasma test facility that includes plasma reactors capable of using up to four plasma jets, flow control instrumentation, an integrated control panel to operate the facility, a mercury generation system that employs a temperature controlled oven and permeation tube, combustible and mercury gas analyzers, and a ductless fume hood designed to capture fugitive mercury emissions. Continental Research and Engineering (CR&E) and Western Research Institute (WRI) successfully demonstrated that non-thermal plasma containing oxygen and chlorine-oxygen reagents could completely convert elemental mercury to an ionic form. These results demonstrate potential the

  12. High-throughput blood cell focusing and plasma isolation using spiral inertial microfluidic devices.

    Science.gov (United States)

    Xiang, Nan; Ni, Zhonghua

    2015-12-01

    Herein, we explored the blood cell focusing and plasma isolation using a spiral inertial microfluidic device. First, the flow-rate and concentration effects on the migration dynamics of blood cells were systematically investigated to uncover the focusing mechanisms and steric crowding effects of cells in Dean-coupled inertial flows. A novel phenomenon that the focusing status of discoid red blood cells (RBCs) changes according to the channel height was discovered. These experimental data may provide valuable insights for the high-throughput processing of blood samples using inertial microfluidics. On the basis of the improved understandings on blood cell focusing, efficient isolation of plasma from whole blood with a 20-fold dilution was achieved at a throughput up to 700 μl/min. The purity of the isolated blood plasma was close to 100 %, and the plasma yield was calculated to be 38.5 %. As compared with previously-reported devices, our spiral inertial microfluidic device provides a balanced overall performance, and has overriding advantages in terms of processing throughput and operating efficiency.

  13. Development of a new experimental device for long-duration magnetic reconnection in weakly ionized plasma

    Science.gov (United States)

    Yanai, Ryoma; Kaminou, Yasuhiro; Nishida, Kento; Inomoto, Michiaki

    2016-10-01

    Magnetic reconnection is a universal phenomenon which determines global structure and energy conversion in magnetized plasmas. Many experimental studies have been carried out to explore the physics of magnetic reconnection in fully ionized condition. However, it is predicted that the behavior of magnetic reconnection in weakly ionized plasmas such as solar chromosphere plasma will show different behavior such as ambipolar diffusion caused by interaction with neutral particles. In this research, we are developing a new experimental device to uncover the importance of ambipolar diffusion during magnetic reconnection in weakly ionized plasmas. We employ an inverter-driven rotating magnetic fields technique, which is used for generating steady azimuthal plasma current, to establish long-duration ( 1 ms) anti-parallel reconnection with magnetic field of 5 mT in weakly ionized plasma. We will present development status and initial results from the new experimental setup. This work was supported by JSPS A3 Foresight Program ``Innovative Tokamak Plasma Startup and Current Drive in Spherical Torus'', Giant-in Aid for Scientific Research (KAKENHI) 15H05750, 15K14279, 26287143 and the NIFS Collaboration Research program (NIFS14KNWP004).

  14. Influence of Downstream Flow on Conduction Phase of Coaxial Plasma Opening Switch

    Institute of Scientific and Technical Information of China (English)

    XU Xiang; WANG Younian

    2008-01-01

    Plasma behaviour and the scaling relations in a coaxial plasma opening switch (POS) using hydrogen plasma are studied self-consistently based on the two-dimensional magnetohydro-dynamic (MHD) equations in conjunction with the generalized Ohm's law. The vacuum region on the right of POS is included in the model and the influence of downstream flow on the conduction characteristics is discussed. It is found that with the penetration of magnetic field, the pure hydro-gen plasma is pushed downstream significantly; and POS still conducts current after the magnetic field arrives at the load edge of POS, which is different from the previous experimental results in a multispecies POS. It is because that the noticeable downstream plasma in the pure hydrogen POS may continue to conduct the current, while in the multispecies POS, the downstream plasma is unimportant so that the conduction phase ends soon after the magnetic field reaches the load edge. The scaling relation obtained from the simulations including the downstream region is consistent with the experimental results.

  15. Protection of active implant electronics with organosilicon open air plasma coating for plastic overmolding

    Directory of Open Access Journals (Sweden)

    Zeppenfeld Matthias

    2016-09-01

    Full Text Available To overcome challenges for manufacturing of modern smart medical plastic parts by injection molding, e.g. for active implants, the optimization of the interface between electronics and the polymer component concerning adhesion and diffusion behavior is crucial. Our results indicate that a nano-sized SiOxCyHz layer formed by plasma-enhanced chemical vapour deposition (PE-CVD via open air atmospheric pressure plasma jet (APPJ and by use of a hexamthyldisiloxane (HMDSO precursor can form a non-corrosive, anti-permeable and biocompatible coating. Due to the open air character of the APPJ process an inline coating before overmolding could be an easy applicable method and a promising advancement.

  16. The in-situ diagnosis of plasma-wall interactions on magnetic fusion devices with accelerators

    Science.gov (United States)

    Hartwig, Zachary

    2013-10-01

    We present the first in-situ, time-resolved measurements of low-Z isotope composition and deuterium retention over a large plasma-facing component (PFC) surface area in a magnetic fusion device. These critical measurements were made using a novel diagnostic technique based on the analysis of induced nuclear reactions from PFC surfaces on the Alcator C-Mod tokamak. Achieving an integrated understanding of plasma physics and materials science in magnetic fusion devices is severely hindered by a dearth of in-situ PFC surface diagnosis. Plasma-wall interactions, such as the erosion/redeposition of PFC material, the evolution of PFC surface isotope composition, and fusion fuel retention present significant plasma physics and materials science challenges for long pulse or steady-state devices. Our diagnostic uses a compact (~1 meter), high-current (~1 milliamp) radio-frequency quadrupole accelerator to inject ~1 MeV deuterons into the vacuum vessel. We control the tokamak's magnetic fields - in between plasma shots - to steer the deuterons to PFC surfaces, where they induce high-Q nuclear reactions with low-Z isotopes in the first ~10 microns of material. Analysis of the induced gamma and neutron energy spectra provides quantitative reconstruction of PFC surface conditions. This nondestructive, in-situ technique achieves PFC surface composition measurements with plasma shot-to-shot time resolution and 1 centimeter spatial resolution over large PFC areas. Work supported by U.S. DOE Grant DE-FG02-94ER54235 and Cooperative Agreement DE-FC02-99ER54512.

  17. Development of a simple device for processing whole-blood samples into measured aliquots of plasma.

    Science.gov (United States)

    Burtis, C A; Johnson, W F; Walker, W A

    1986-09-01

    A capillary processor and aliquoter has been designed and fabricated that is capable of accepting aliquots of whole blood and automatically processing them into discrete aliquots of plasma. The device consists of two disks, each of which contains 16 individual capillaries and a processing rotor. One disk accepts larger capillaries that hold approximately 100 microL of whole blood each. The second disk accepts 2.54-cm-long precision capillaries of various internal diameters, which provide exact sample volumes from 1 to 10 microL. The processing rotor contains 16 individual compartments and chambers to accept both disks. Applying centrifugal force transfers the aliquots of whole blood into their respective compartments, where they are separated into cellular and plasma fractions. As the rotor speed is slowly decreased, an aliquot of plasma is withdrawn by capillary action into each measuring capillary. The disk containing the 16 measured aliquots of plasma is then removed and placed into a modified rotor for conventional centrifugal analysis. This device can entrain and deliver microliter volumes of liquids with precision and accuracy (1-2%) near that of mechanical pipettes. Assays of the separated plasma aliquots also have acceptable precision (e.g., CVs approximately 3% for measurements of serum enzymes).

  18. Modelling of the internal dynamics and density in a tens of joules plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Marquez, Ariel [CNEA and Instituto Balseiro, 8402 Bariloche (Argentina); Gonzalez, Jose [INVAP-CONICET and Instituto Balseiro, 8402 Bariloche, Argentina. (Argentina); Tarifeno-Saldivia, Ariel; Pavez, Cristian; Soto, Leopoldo [CCHEN, Comision Chilena de Energia Nuclear, Casilla 188-D, Santiago (Chile); Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile); Clausse, Alejandro [CNEA-CONICET and Universidad Nacional del Centro, 7000 Tandil (Argentina)

    2012-01-15

    Using MHD theory, coupled differential equations were generated using a lumped parameter model to describe the internal behaviour of the pinch compression phase in plasma focus discharges. In order to provide these equations with appropriate initial conditions, the modelling of previous phases was included by describing the plasma sheath as planar shockwaves. The equations were solved numerically, and the results were contrasted against experimental measurements performed on the device PF-50J. The model is able to predict satisfactorily the timing and the radial electron density profile at the maximum compression.

  19. Management of open olecranon fractures using clamp-cum-compressor device

    Directory of Open Access Journals (Sweden)

    Kundu Zile

    2009-01-01

    Full Text Available Background: Open fractures of olecranon are not a rare occurrence in patients with road traffic accidents particularly motor bike riders who don′t use elbow guards. Definitive treatment has to be delayed in many till the wound heals. The present study was conducted to evaluate the results of open fractures of olecranon using clamp-cum-compressor device. Materials and Methods: Seventeen patients between the ages of 20 and 45 years of open olecranon fractures reported 5-20 days after injury were treated using an indigenous clamp-cum-compressor. All fractures were Mayo type II-A, i.e., displaced, stable and noncomminuted. Four patients had Gustilo-Anderson grade I and 13 had Gustilo-Anderson grade II open fractures. The patients with transverse or short oblique fractures were included in the study. The apparatus was applied under regional anesthesia after thorough washing and debridement of wounds with few loose sutures applied wherever needed. The wounds healed within 2-4 weeks and fractures united within 8-10 weeks. The elbow was mobilized with apparatus still in place. The results were evaluated by MayoElbow performance score. Results: We achieved excellent results in twelve patients, good in four and poor in one patient, who reported late, hooks of the apparatus were cut through the proximal fragment, leading to union of fracture in elongation and restricted elbow movements. Conclusion: The apparatus was found to be quite useful in transverse and short oblique fractures with contamination or infection, where internal fixation has to be delayed or avoided.

  20. Plasma-on-chip device for stable irradiation of cells cultured in media with a low-temperature atmospheric pressure plasma.

    Science.gov (United States)

    Okada, Tomohiro; Chang, Chun-Yao; Kobayashi, Mime; Shimizu, Tetsuji; Sasaki, Minoru; Kumagai, Shinya

    2016-09-01

    We have developed a micro electromechanical systems (MEMS) device which enables plasma treatment for cells cultured in media. The device, referred to as the plasma-on-chip, comprises microwells and microplasma sources fabricated together in a single chip. The microwells have through-holes between the microwells and microplasma sources. Each microplasma source is located on the backside of each microwells. The reactive components generated by the microplasma sources pass through the through-holes and reach cells cultured in the microwells. In this study, a plasma-on-chip device was modified for a stable plasma treatment. The use of a dielectric barrier discharge (DBD) technique allowed a stable plasma treatment up to 3 min. The plasma-on-chip with the original electrode configuration typically had the maximum stable operation time of around 1 min. Spectral analysis of the plasma identified reactive species such as O and OH radicals that can affect the activity of cells. Plasma treatment was successfully performed on yeast (Saccharomyces cerevisiae) and green algae (Chlorella) cells. While no apparent change was observed with yeast, the treatment degraded the activity of the Chlorella cells and decreased their fluorescence. The device has the potential to help understand interactions between plasma and cells.

  1. Energy-dependent finite-orbit treatment for plasma buildup in mirror fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, M.M.

    1980-01-01

    A computer simulation of hot plasma buildup in mirror fusion devices and results from this model are presented. In a small, hot magnetically confined plasma, the ion orbit radius (rho/sub i/) can be comparable to the plasma radius (R/sub p/). It a mirror-confined plasma were rho/sub i//R/sub p/ > 1/25 (such as 2XII-B), a point kinetic treatment of ion interactions becomes inaccurate and a finite gyro-radius (FGR) treatment must be used to adequately describe plasma buildup processes. This is particularly true for describing losses due to cold-gas charge exchange (c-x) near the plasma surface, since a particle lost near the vacuum interface may have contributed to the density as far as 2 rho/sub i/ radially inward from the c-x point. A similar FGR effect applies to beam-deposited ions whose large orbits influence the density up to 2 rho/sub i/ from the trapping point.

  2. Spontaneous excitation of waves by an intense ion beam on the Large Plasma Device

    Science.gov (United States)

    Tripathi, Shreekrishna; van Compernolle, Bart; Gekelman, Walter; Pribyl, Patrick; Heidbrink, William

    2016-10-01

    A hydrogen ion beam (15 keV, 10 A) has been injected into a large magnetized plasma (n 1010 -1013 cm-3, Te = 5.0 - 15.0 eV, B = 0.6 - 1.8 kG, He+ and H+ ions, 19 m long, 0.6 m diameter) for performing fast-ion studies on the Large Plasma Device (LAPD). The beam forms a helical orbit (pitch-angle 7° -55°), propagates with an Alfvénic speed (beam-speed/Alfvén-speed = 0.2 - 3.0), and significantly enhances the electron temperature and density when injected during the plasma afterglow. We report results on spontaneous generation of Alfvén waves and electrostatic waves in the lower-hybrid range of frequencies by the beam. Roles of normal and anomalous Doppler-shifted ion-cyclotron resonances in destabilizing the Alfvén waves were examined by measuring the phase-speed of waves and relevant parameters of the plasma using a variety of diagnostic tools (retarding-field energy analyzer, three-axis magnetic-loop, Dipole, and Langmuir probes). Conditions for the maximum growth of these waves were determined by varying the parameters of the beam and ambient plasma and examining the mode-structures in the fluctuation-spectra. Work jointly supported by US DOE and NSF and performed at the Basic Plasma Science Facility, UCLA.

  3. Capillarity-driven blood plasma separation on paper-based devices.

    Science.gov (United States)

    Kar, Shantimoy; Maiti, Tapas Kumar; Chakraborty, Suman

    2015-10-01

    We demonstrate capillarity-driven plasma separation from whole blood on simple paper-based H-channels. This methodology, unlike other reported techniques, does not necessitate elaborate and complex instrumentation, and the usage of expensive consumables. We believe that this technique will be ideally suited to be implemented in rapid and portable blood diagnostic devices designed to be operative at locations with limited resources.

  4. Numerical Analysis of Amirkabir Plasma Focus (APF) Device for Neon and Argon Gases

    Science.gov (United States)

    Niknam Sharak, M.; Goudarzi, S.; Raeisdana, A.; Jafarabadi, M.

    2013-04-01

    In this paper the experimental results in different working conditions in Amirkabir Plasma Focus (APF) Device have been compared with the numerical results of a two-dimensional simulation code based on Lee's model. The experiments were done with pure Neon and Argon as operating gases over a wide range of working conditions (gas pressures and discharge voltages). It is observed that by a proper choice for values of the efficiency factors, comparison between numerical and experimental results shows a good agreement.

  5. Effect of the RF wall conditioning on the high performance plasmas in the Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, H., E-mail: takahashi.hiromi@LHD.nifs.ac.jp [National Institute for Fusion Science, Toki 509-5292 (Japan); Osakabe, M.; Nagaoka, K.; Nakano, H.; Tokitani, M. [National Institute for Fusion Science, Toki 509-5292 (Japan); Fujii, K. [Department of Mechanical Engineering and Science, Kyoto University, Kyoto 615-8540 (Japan); Murakami, S. [Department of Nuclear Engineering, Kyoto University, Kyoto 606-8501 (Japan); Takeiri, Y.; Seki, T.; Saito, K.; Kasahara, H.; Seki, R.; Kamio, S.; Masuzaki, S.; Mutoh, T. [National Institute for Fusion Science, Toki 509-5292 (Japan)

    2015-08-15

    The wall conditioning using radio frequency (RF) plasma was carried out using Ion Cyclotron Range of Frequency (ICRF) heating and/or Electron Cyclotron Resonance Heating (ECRH) with the working gas of helium under the established confinement magnetic field. After sufficient numbers of repetitive wall discharge conditioning (DC, ICDC for ICRF and ECDC for ECRH), the formation of the parabolic electron density profile and the increase of the central ion temperature T{sub i} were observed. There was no difference in the attained central T{sub i} of the NBI discharge just after the conditioning using a similar value of input energy regardless of the applied RF source. Thus, it is concluded that both ICDC and the ECDC are effective for the higher T{sub i} plasma production under the established magnetic field in the Large Helical Device. The effective RF wall conditioning scenarios are also investigated for high T{sub i} plasma production.

  6. The power-supply control system in the device of acetylene production by H-plasma pyrolysis coal

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.Y.; Zhang, M.; Fu, P.; Weng, P.D. [Chinese Academy of Sciences, Hefei (China)

    2006-09-15

    The device of acetylene production by hydrogen (H{sub 2}) plasma pyrolysis coal is examined and developed not only for studying the application of low temperature plasma but also for studying the clean use of coal. The power-supply control system is used to ensure supplying a steady energy to generate and maintain the plasma electric arc of the device. The hardware configuration and the software design of the system are described in this paper. Verified by experiments, this system can meet the requirements of real-time performance, reliability and extensibility for the device.

  7. The Power-Supply Control System in the Device of Acetylene Production by H-Plasma Pyrolysis Coal

    Science.gov (United States)

    Chen, Feiyun; Zhang, Ming; Fu, Peng; Weng, Peide

    2006-09-01

    The device of acetylene production by hydrogen (H-) plasma pyrolysis coal is examined and developed not only for studying the application of low temperature plasma but also for studying the clean use of coal. The power-supply control system is used to ensure supplying a steady energy to generate and maintain the plasma electric arc of the device. The hardware configuration and the software design of the system are described in this paper. Verified by experiments, this system can meet the requirements of real-time performance, reliability and extensibility for the device.

  8. Inkjet patterned superhydrophobic paper for open-air surface microfluidic devices.

    Science.gov (United States)

    Elsharkawy, Mohamed; Schutzius, Thomas M; Megaridis, Constantine M

    2014-03-21

    We present a facile approach for the fabrication of low-cost surface biomicrofluidic devices on superhydrophobic paper created by drop-casting a fluoroacrylic copolymer onto microtextured paper. Wettability patterning is performed with a common household printer, which produces regions of varying wettability by simply controlling the intensity of ink deposited over prespecified domains. The procedure produces surfaces that are capable of selective droplet sliding and adhesion, when inclined. Using this methodology, we demonstrate the ability to tune the sliding angles of 10 μL water droplets in the range from 13° to 40° by printing lines of constant ink intensity and varied width from 0.1 mm to 2 mm. We also formulate a simple model to predict the onset of droplet sliding on printed lines of known width and wettability. Experiments demonstrate open-air surface microfluidic devices that are capable of pumpless transport, mixing and rapid droplet sampling (~0.6 μL at 50 Hz). Lastly, post treatment of printed areas with pH indicator solutions exemplifies the utility of these substrates in point-of-care diagnostics, which are needed at geographical locations where access to sophisticated testing equipment is limited or non-existent.

  9. Portable Low-Frequency Noise Reduction Device for Both Small Open and Closed Spaces

    Directory of Open Access Journals (Sweden)

    Chao Wang

    2016-01-01

    Full Text Available Noise pollution has been given more attention due to its negative impacts on human health and disease. The portable low-frequency noise reduction device we developed in this research can provide an effective way for solving low-frequency noise pollution problem in the small space. This work describes the design principle and the prototype structures for two versions of V1.5 and V2.0 and builds the noise test systems for small spaces, respectively. These devices, installed on the outer surface of the small spaces, can automatically identify the noise spectrum and implement noise reduction by means of the active noise control (ANC technology. The testing results indicate that the noise can be reduced 12 dB in the range of 250 Hz~400 Hz for the small closed space while, for the small open space, the best effect of 5.88 dB occurs in the optimal frequency of 450 Hz. These effects will be weakened with the increasing distance away from the source and show the obvious axisymmetric distribution in the inverted cone space.

  10. Gap formation processes in a high-density plasma opening switch

    Science.gov (United States)

    Grossmann, J. M.; Swanekamp, S. B.; Ottinger, P. F.; Commisso, R. J.; Hinshelwood, D. D.; Weber, B. V.

    1995-01-01

    A gap opening process in plasma opening switches (POS) is examined with the aid of numerical simulations. In these simulations, a high density (ne=1014-5×1015 cm-3) uniform plasma initially bridges a small section of the coaxial transmission line of an inductive energy storage generator. A short section of vacuum transmission line connects the POS to a short circuit load. The results presented here extend previous simulations in the ne=1012-1013 cm-3 density regime. The simulations show that a two-dimensional (2-D) sheath forms in the plasma near a cathode. This sheath is positively charged, and electrostatic sheath potentials that are large compared to the anode-cathode voltage develop. Initially, the 2-D sheath is located at the generator edge of the plasma. As ions are accelerated out of the sheath, it retains its original 2-D structure, but migrates axially toward the load creating a magnetically insulated gap in its wake. When the sheath reaches the load edge of the POS, the POS stops conducting current and the load current increases rapidly. At the end of the conduction phase a gap exists in the POS whose size is determined by the radial dimensions of the 2-D sheath. Simulations at various plasma densities and current levels show that the radial size of the gap scales roughly as B/ne, where B is the magnetic field. The results of this work are discussed in the context of long-conduction-time POS physics, but exhibit the same physical gap formation mechanisms as earlier lower density simulations more relevant to short-conduction-time POS.

  11. Carbon Nanofibers Functionalized with Active Screen Plasma-Deposited Metal Nanoparticles for Electrical Energy Storage Devices.

    Science.gov (United States)

    Corujeira Gallo, Santiago; Li, Xiaoying; Fütterer, Klaus; Charitidis, Constantinos A; Dong, Hanshan

    2017-07-12

    Supercapacitors are energy storage devices with higher energy densities than conventional capacitors but lower than batteries or fuel cells. There is a strong interest in increasing the volumetric and gravimetric capacitance of these devices to meet the growing demands of the electrical and electronic sectors. The capacitance depends largely on the electrode material, and carbon nanofibers (CNFs) have attracted much attention because of their relatively low cost, large surface area, and good electrical conductivity as well as chemical and thermal stability. The deposition of metal nanoparticles on CNFs is a promising way to increase their surface properties and, ultimately, the capacitance of the devices. In this study, nickel and silver nanoparticles were deposited on CNFs using the active screen plasma technology. The CNFs were characterized, and their electrochemical performance was assessed in a three-electrode cell. The results show significant improvements over the untreated CNFs, particularly after functionalization with silver nanoparticles.

  12. Moderation of neoclassical impurity accumulation in high temperature plasmas of helical devices

    CERN Document Server

    Velasco, J L; Satake, S; Alonso, A; Nunami, M; Yokoyama, M; Sato, M; Dinklage, A; Estrada, T; Fontdecaba, J M; Liniers, M; McCarthy, K J; Medina, F; Van Milligen, B Ph; Ochando, M; Parra, F; Sugama, H; Zhezhera, A

    2016-01-01

    Achieving impurity and helium ash control is a crucial issue in the path towards fusion-grade magnetic confinement devices, and this is particularly the case of helical reactors, whose low-collisionality ion-root operation scenarios usually display a negative radial electric field which is expected to cause inwards impurity pinch. In these work we discuss, based on experimental measurements and standard predictions of neoclassical theory, how plasmas of very low ion collisionality, similar to those observed in the impurity hole of the Large Helical Device, can be an exception to this general rule, and how a negative radial electric field can coexist with an outward impurity flux. This interpretation is supported by comparison with documented discharges available in the International Stellarator-Heliotron Profile Database, and it can be extrapolated to show that achievement of high ion temperature in the core of helical devices is not fundamentally incompatible with low core impurity content.

  13. Outlook for the use of microsecond plasma opening switches to generate high-power nanosecond current pulses

    Science.gov (United States)

    Dolgachev, G. I.; Maslennikov, D. D.; Ushakov, A. G.

    2006-12-01

    An analysis is made of the current break process in microsecond plasma opening switches and their possible application in high-current generators. Necessary conditions are determined for generating megavolt pulses in the erosion mode of a plasma opening switch with the gap insulated by an external magnetic field. Under these conditions, efficient sharpening of high-power submegampere current pulses can be achieved. The possibility of using plasma opening switches operating at voltages of 5 6 MV to generate X-ray and gamma emission is discussed. The main operating and design parameters of a six-module plasma opening switch with a current pulse amplitude of 3.7 MA and voltage of 4 6 MV for use in the MOL generator, which is the prototype of one of the 24 modules of the projected Baikal multimegajoule generator, are estimated by using the available scalings.

  14. Imperative function of electron beams in low-energy plasma focus device

    Indian Academy of Sciences (India)

    M Z Khan; L K Lim; S L Yap; C S Wong

    2015-12-01

    A 2.2 kJ plasma focus device was analysed as an electron beam and an X-ray source that operates with argon gas refilled at a specific pressure. Time-resolved X-ray signals were observed using an array of PIN diode detectors, and the electron beam energy was detected using a scintillator-assisted photomultiplier tube. The resultant X-rays were investigated by plasma focus discharge for pressures ranging from 1.5 mbar to 2.0 mbar. This range corresponded to the significant values of X-ray yields and electron beam energies from the argon plasma. The electron temperature of argon plasma at an optimum pressure range was achieved by an indirect method using five-channel BPX65 PIN diodes of aluminum foils with different thicknesses. X-ray yield, electron beam energy, and electron temperature of argon plasma were achieved at 1.5–2.0 mbar because of the strong bombardment of the energetic electron beam.

  15. Open air plasma deposited antimicrobial SiOx/TiOx composite films for biomedical applications

    Directory of Open Access Journals (Sweden)

    Rapp Christin

    2016-09-01

    Full Text Available Open air atmospheric pressure plasma jet (APPJ enhanced chemical vapour deposition process was used to deposit biocompatible SiOx/TiOx composite coatings. The as deposited films are hydrophilic and show visible light induced photocatalytic effect, which is a consequence of the formation of defects in the TiOx structure due to the plasma process. This photocatalytic effect was verified by the demonstration of an antimicrobial effect under visible light on E. coli as well as by degradation of Rhodamine B. The films are non-cytotoxic as shown by the cytocompatibility tests. The films are conductive to cell growth and are stable in DMEM and isopropanol. The structural evaluation using SEM, EDS and XPS shows a dispersion of TiOx phase in a SiOxCyHz matrix. These analyses were used to correlate the structure-property relationship of the composite coating.

  16. Experimental study of the performance of a very small repetitive plasma focus device in different working conditions

    Science.gov (United States)

    Goudarzi, S.; Babaee, H.; Esmaeli, A.; Nasiri, A.

    2017-01-01

    SORENA-1 is a very small repetitive Mather-type plasma focus device (20 J) that can operate at frequencies up to 1 Hz. This device has been designed and constructed in the Plasma and Nuclear Fusion Research School of the Nuclear Science and Technology Research Institute of Iran. In this article, the structure of SORENA-1 is described and results of experiments with Ar, Ne, and D2 working gases at several discharge voltages and initial pressures are presented and analyzed.

  17. Hole injection enhancement in organic light emitting devices using plasma treated graphene oxide

    Science.gov (United States)

    Jesuraj, P. Justin; Parameshwari, R.; Kanthasamy, K.; Koch, J.; Pfnür, H.; Jeganathan, K.

    2017-03-01

    The hole injection layer (HIL) with high work function (WF) is desirable to reduce the injection barrier between anode and hole transport layer in organic light emitting devices (OLED). Here, we report a novel approach to tune the WF of graphene oxide (GO) using oxygen and hydrogen plasma treatment and its hole injection properties in OLEDs. The mild exposure of oxygen plasma on GO (O2-GO) significantly reduces the injection barrier by increasing the WF of anode (4.98 eV) through expansion of Csbnd O bonds. In contrast, the hole injection barrier was drastically increased for hydrogen plasma treated GO (H2-GO) layers as the WF is lowered by the contraction of Csbnd O bond. By employing active O2-GO as HIL in OLEDs found to exhibit superior current efficiency of 4.2 cd/A as compared to 3.3 cd/A for pristine GO. Further, the high injection efficiency of O2-GO infused hole only device can be attributed to the improved energy level matching. Ultraviolet and X-ray photoelectron spectroscopy were used to correlate the WF of HIL infused anode towards the enhanced performance of OLEDs with their capricious content of Csbnd O in GO matrix.

  18. The differing behavior of electrosurgical devices made of various electrode materials operating under plasma conditions

    Science.gov (United States)

    Stalder, K. R.; Ryan, T. P.; Gaspredes, J.; Woloszko, J.

    2015-03-01

    Coblation® is an electrosurgical technology which employs electrically-excited electrodes in the presence of saline solution to produce a localized and ionized plasma that can cut, ablate, and otherwise treat tissues for many different surgical needs. To improve our understanding of how Coblation plasmas develop from devices made from different electrode materials we describe several experiments designed to elucidate material effects. Initial experiments studied simple, noncommercial cylindrical electrode test devices operating in buffered isotonic saline without applied suction. The applied RF voltage, approximately 300 V RMS, was sufficient to form glow discharges around the active electrodes. The devices exhibited significantly different operating characteristics, which we ascribe to the differing oxidation tendencies and other physical properties of the electrode materials. Parameters measured include RMS voltage and current, instantaneous voltage and current, temporally-resolved light emission and optical emission spectra, and electrode mass-loss measurements. We correlate these measured properties with some of the bulk characteristics of the electrode materials such as work functions, standard reduction potentials and sputter yields.

  19. Moderation of neoclassical impurity accumulation in high temperature plasmas of helical devices

    Science.gov (United States)

    Velasco, J. L.; Calvo, I.; Satake, S.; Alonso, A.; Nunami, M.; Yokoyama, M.; Sato, M.; Estrada, T.; Fontdecaba, J. M.; Liniers, M.; McCarthy, K. J.; Medina, F.; Van Milligen, B. Ph; Ochando, M.; Parra, F.; Sugama, H.; Zhezhera, A.; The LHD Experimental Team; The TJ-II Team

    2017-01-01

    Achieving impurity and helium ash control is a crucial issue in the path towards fusion-grade magnetic confinement devices, and this is particularly the case of helical reactors, whose low-collisionality ion-root operation scenarios usually display a negative radial electric field which is expected to cause inwards impurity pinch. In this work we discuss, based on experimental measurements and standard predictions of neoclassical theory, how plasmas of very low ion collisionality, similar to those observed in the impurity hole of the large helical device (Yoshinuma et al and The LHD Experimental Group 2009 Nucl. Fusion 49 062002, Ida et al and The LHD Experimental Group 2009 Phys. Plasmas 16 056111 and Yokoyama et al and LHD Experimental Group 2002 Nucl. Fusion 42 143), can be an exception to this general rule, and how a negative radial electric field can coexist with an outward impurity flux. This interpretation is supported by comparison with documented discharges available in the International Stellarator-Heliotron Profile Database, and it can be extrapolated to show that achievement of high ion temperature in the core of helical devices is not fundamentally incompatible with low core impurity content.

  20. A 5 kA pulsed power supply for inductive and plasma loads in large volume plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, P. K., E-mail: pkumar@ipr.res.in; Singh, S. K.; Sanyasi, A. K.; Awasthi, L. M., E-mail: kushagra.lalit@gmail.com; Mattoo, S. K. [Institute for Plasma Research, Gandhinagar (India)

    2016-07-15

    This paper describes 5 kA, 12 ms pulsed power supply for inductive load of Electron Energy Filter (EEF) in large volume plasma device. The power supply is based upon the principle of rapid sourcing of energy from the capacitor bank (2.8 F/200 V) by using a static switch, comprising of ten Insulated Gate Bipolar Transistors (IGBTs). A suitable mechanism is developed to ensure equal sharing of current and uniform power distribution during the operation of these IGBTs. Safe commutation of power to the EEF is ensured by the proper optimization of its components and by the introduction of over voltage protection (>6 kV) using an indigenously designed snubber circuit. Various time sequences relevant to different actions of power supply, viz., pulse width control and repetition rate, are realized through optically isolated computer controlled interface.

  1. A 5 kA pulsed power supply for inductive and plasma loads in large volume plasma device

    Science.gov (United States)

    Srivastava, P. K.; Singh, S. K.; Sanyasi, A. K.; Awasthi, L. M.; Mattoo, S. K.

    2016-07-01

    This paper describes 5 kA, 12 ms pulsed power supply for inductive load of Electron Energy Filter (EEF) in large volume plasma device. The power supply is based upon the principle of rapid sourcing of energy from the capacitor bank (2.8 F/200 V) by using a static switch, comprising of ten Insulated Gate Bipolar Transistors (IGBTs). A suitable mechanism is developed to ensure equal sharing of current and uniform power distribution during the operation of these IGBTs. Safe commutation of power to the EEF is ensured by the proper optimization of its components and by the introduction of over voltage protection (>6 kV) using an indigenously designed snubber circuit. Various time sequences relevant to different actions of power supply, viz., pulse width control and repetition rate, are realized through optically isolated computer controlled interface.

  2. Numerical simulation study on density dependence of plasma detachment in simulated gas divertor experiments of the TPD-I device

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, N. [Nagoya Univ. (Japan). Dept. of Energy Eng. and Sci.; Mori, S. [Nagoya Univ. (Japan). Dept. of Energy Eng. and Sci.; Ezumi, N. [Nagoya Univ. (Japan). Dept. of Energy Eng. and Sci.; Takagi, M. [Nagoya Univ. (Japan). Dept. of Energy Eng. and Sci.; Takamura, S. [Nagoya Univ. (Japan). Dept. of Energy Eng. and Sci.; Suzuki, H. [National Inst. for Fusion Science, Nagoya (Japan)

    1996-08-01

    It is one of the most critical requirements to reduce the heat load to the divertor plate in the next generation fusion devices such as ITER, intended to have a long pulse or a steady state operation. Dynamic gas target divertor as well as high recycling divertor is one of the most important candidates for ITER. Recently a detached plasma has been observed in experimental fusion devices. Knowledge of the basic physics of the plasma detachment is required for any application of the gas target and high recycling divertor to the next generation experimental reactors. Linear plasma divertor simulators with high heat flux plasmas are used to investigate the plasma detachment because its good accessibility for comprehensive measurements and simple geometry leads a deeper understanding of the plasma detachment by comparing between simulation predictions and the experimental results. (orig.)

  3. Simulation of electrical discharge in a 3.6 Joule miniature plasma focus device using SIMULINK

    Science.gov (United States)

    Jafari, Hossein; Habibi, Morteza

    2014-08-01

    A novel technique has been developed and studied in this paper to simulate the electrical discharge circuit of a 3.6 J miniature plasma focus device (PFD) and investigate the effect of inductance variation on voltage spike and current dip. The technique is based on a correlation between the electrical discharge circuit and plasma dynamics in a very small PFD that operates at the energy of 3.6 J. The simulation inputs include the charging voltage, capacitor bank capacitance, current limiter resistance, by-pass resistance as well as the time-dependent inductance and resistance of the plasma sheath which are calculated by assuming the plasma dynamics as transit times in going from one phase to the next. The variations of the most important elements in the circuit (i.e. the constant and breakdown inductances) and their effects on the current dip are studied in PFDs with low and high constant inductance. The model demonstrated for achieving a good pinch in the PFD, although the total inductance of the system should be low; however there is always an optimum inductance which causes an appropriate pinch. Furthermore, the electrical power produced by the pulsed power supply, the mechanical energy as well as the magnetic energy which are transferred into the plasma tube were obtained from simulation. The graph of electrical power demonstrated a high instantaneous increment in the power transferred into the plasma as one of the greatest advantages of the pulsed power supply. The simulation was performed using software tools within the MATLAB/SIMULINK simulation environment.

  4. Are temporary anchorage devices truly effective in the treatment of skeletal open bites?

    Science.gov (United States)

    Turkkahraman, Hakan; Sarioglu, Mehmet

    2016-01-01

    Objective: The aims of this study were to evaluate the effects of temporary anchorage devices (TADs) in the treatment of skeletal open bites and to compare the results with untreated controls. Materials and Methods: A total of forty patients with skeletal anterior open bites were assigned to two groups of twenty each. The mean chronological age for the treatment group (14 female, 6 male) was 16.68 ± 2.80 years old, compared with 16.63 ± 2.83 years old for the control group (11 female, 9 male). Titanium miniplates fixed bilaterally to the infrazygomatic crest area were used as TADs and intrusive forces were applied to the posterior teeth with Ni-Ti coil springs. The treatment and normal growth changes were evaluated using 24 measurements (2 angular, 22 linear). Results: Statistically significant differences were found between the groups in Bx, By, Sn/GoGn, Ax-Bx, U6x, U6y, overjet, overbite, SN/OccP, N-Me, Ans-Me, S-Go/N-Me, interpremolar width, and intermolar width (P < 0.05). In the treatment group, statistically significant upper molar intrusion (mean ± standard deviation [SD], 3.59 ± 1.34; 95% confidence interval [CI], 2.96–4.22), posterior rotation of the occlusal plane (mean ± SD, 3.42 ± 2.17; 95% CI, 2.39–4.43), anterior rotation of the mandible (mean ± SD, 2.25 ± 1.91; 95% CI, 1.36–3.14), and resultant overbite improvement (mean ± SD, 4.82 ± 1.53; 95% CI, 4.10–5.53) were found (P < 0.05). Conclusions: Mild to moderate skeletal anterior open bites could easily be treated with TADs without orthognathic surgery. With the rigid anchorage of miniplates, true molar intrusion of up to 4 mm was achieved. With molar intrusion, anterior rotation of the mandible and a significant reduction in anterior face height were determined. PMID:28042256

  5. Collisional damping of helicon waves in a high density hydrogen linear plasma device

    Science.gov (United States)

    Caneses, Juan F.; Blackwell, Boyd D.

    2016-10-01

    In this paper, we investigate the propagation and damping of helicon waves along the length (50 cm) of a helicon-produced 20 kW hydrogen plasma ({{n}\\text{e}}∼ 1–2 × 1019 m‑3, {{T}\\text{e}}∼ 1–6 eV, H2 8 mTorr) operated in a magnetic mirror configuration (antenna region: 50–200 G and mirror region: 800 G). Experimental results show the presence of traveling helicon waves (4–8 G and {λz}∼ 10–15 cm) propagating away from the antenna region which become collisionally absorbed within 40–50 cm. We describe the use of the WKB method to calculate wave damping and provide an expression to assess its validity based on experimental measurements. Theoretical calculations are consistent with experiment and indicate that for conditions where Coulomb collisions are dominant classical collisionality is sufficient to explain the observed wave damping along the length of the plasma column. Based on these results, we provide an expression for the scaling of helicon wave damping relevant to high density discharges and discuss the location of surfaces for plasma-material interaction studies in helicon based linear plasma devices.

  6. Hybrid simulation of a parallel collisionless shock in the Large Plasma Device

    CERN Document Server

    Weidl, M S; Jenko, F; Niemann, C

    2016-01-01

    We present two-dimensional hybrid kinetic/magnetohydrodynamic simulations of planned laser-ablation experiments in the Large Plasma Device (LAPD). Our results, based on parameters which have been validated in previous experiments, show that a parallel collisionless shock can begin forming within the available space. Carbon-debris ions that stream along the magnetic-field direction with a blow-off speed of four times the Alfven velocity excite strong magnetic fluctuations, eventually transfering part of their kinetic energy to the surrounding hydrogen ions. This acceleration and compression of the background plasma creates a shock front, which satisfies the Rankine-Hugoniot conditions and can therefore propagate on its own. Furthermore, we analyze the upstream turbulence and show that it is dominated by the right-hand resonant instability.

  7. Parabolic lithium mirror for a laser-driven hot plasma producing device

    Science.gov (United States)

    Baird, James K.

    1979-06-19

    A hot plasma producing device is provided, wherein pellets, singly injected, of frozen fuel are each ignited with a plurality of pulsed laser beams. Ignition takes place within a void area in liquid lithium contained within a pressure vessel. The void in the liquid lithium is created by rotating the pressure vessel such that the free liquid surface of molten lithium therein forms a paraboloid of revolution. The paraboloid functions as a laser mirror with a reflectivity greater than 90%. A hot plasma is produced when each of the frozen deuterium-tritium pellets sequentially arrive at the paraboloid focus, at which time each pellet is illuminated by the plurality of pulsed lasers whose rays pass through circular annuli across the top of the paraboloid. The beams from the lasers are respectively directed by associated mirrors, or by means of a single conical mirror in another embodiment, and by the mirror-like paraboloid formed by the rotating liquid lithium onto the fuel pellet such that the optical flux reaching the pellet can be made to be uniform over 96% of the pellet surface area. The very hot plasma produced by the action of the lasers on the respective singly injected fuel pellets in turn produces a copious quantity of neutrons and X-rays such that the device has utility as a neutron source or as an x-ray source. In addition, the neutrons produced in the device may be utilized to produce tritium in a lithium blanket and is thus a mechanism for producing tritium.

  8. Reconstruction of improvised explosive device blast loading to personnel in the open

    Science.gov (United States)

    Wiri, Suthee; Needham, Charles

    2016-05-01

    Significant advances in reconstructing attacks by improvised explosive devices (IEDs) and other blast events are reported. A high-fidelity three-dimensional computational fluid dynamics tool, called Second-order Hydrodynamic Automatic Mesh Refinement Code, was used for the analysis. Computer-aided design models for subjects or vehicles in the scene accurately represent geometries of objects in the blast field. A wide range of scenario types and blast exposure levels were reconstructed including free field blast, enclosed space of vehicle cabin, IED attack on a vehicle, buried charges, recoilless rifle operation, rocket-propelled grenade attack and missile attack with single subject or multiple subject exposure to pressure levels from ˜ 27.6 kPa (˜ 4 psi) to greater than 690 kPa (>100 psi). To create a full 3D pressure time-resolved reconstruction of a blast event for injury and blast exposure analysis, a combination of intelligence data and Blast Gauge data can be used to reconstruct an actual in-theatre blast event. The methodology to reconstruct an event and the "lessons learned" from multiple reconstructions in open space are presented. The analysis uses records of blast pressure at discrete points, and the output is a spatial and temporal blast load distribution for all personnel involved.

  9. In-channel printing-device opening assay for micropatterning multiple cells and gene analysis.

    Science.gov (United States)

    Zhou, Hao; Zhao, Liang; Zhang, Xueji

    2015-02-17

    Herein we report an easy but versatile method for patterning different cells on a single substrate by using a microfluidic approach that allows not only spatial and temporal control of multiple microenvironments but also retrieval of specific treated cells to profile their expressed genetic information at around 10-cell resolution. By taking advantages of increased surface area of gold nanoparticles on a poly(dimethylsiloxane) (PDMS) coated substrate, cell adhesive-promotive protein, human fibronectin (hFN) can be significantly accumulated on designed regions where cells can recognize the protein and spread out. Moreover, the whole device can be easily opened by hand without any loss of patterned cells which could be retrieved by mouth-pipet. Consequently, we demonstrate the possibility of analyzing the difference of gene expression patterns between wild type MCF-7 cell and MCF/Adr (drug-resistant cell line) from less than 400 cells in total for a single comprehensive assay, including parallel experiments, controls, and multiple dose treatments. Certain genes, especially the P-glycoprotein coding gene (ABCB1), show high expression level in resistant cells compared with the wild type, suggesting a possible pathway that may contribute to the antidrug mechanism.

  10. A Tesla-pulse forming line-plasma opening switch pulsed power generator

    Science.gov (United States)

    Novac, B. M.; Kumar, R.; Smith, I. R.

    2010-10-01

    A pulsed power generator based on a high-voltage Tesla transformer which charges a 3.85 Ω/55 ns water-filled pulse forming line to 300 kV has been developed at Loughborough University as a training tool for pulsed power students. The generator uses all forms of insulation specific to pulsed power technology, liquid (oil and water), gas (SF6), and magnetic insulation in vacuum, and a number of fast voltage and current sensors are implemented for diagnostic purposes. A miniature (centimeter-size) plasma opening switch has recently been coupled to the output of the pulse forming line, with the overall system comprising the first phase of a program aimed at the development of a novel repetitive, table-top generator capable of producing 15 GW pulses for high power microwave loads. Technical details of all the generator components and the main experimental results obtained during the program and demonstrations of their performance are presented in the paper, together with a description of the various diagnostic tools involved. In particular, it is shown that the miniature plasma opening switch is capable of reducing the rise time of the input current while significantly increasing the load power. Future plans are outlined in the conclusions.

  11. Calibration constant of a silver activation counter used with plasma focus devices

    Directory of Open Access Journals (Sweden)

    GR Etaati

    2010-03-01

    Full Text Available The silver activation counters are commonly used for pulsed-neutron yield measurements especially in plasma focus devices. The counter normally consists of a Geiger-Muller tube along with silver foils and polyethylene (as a moderator, which is calibrated against an Am-Be radioisotope neutron source. The neutrons, after being slowed-down in the polyethylene, activate the silver foils. By measuring the foil activity with a Geiger-Muller counter, the neutron yield is determined. In the present paper, the activation counter’s calibration constant calculation using the MCNP4C code is explained. The calculated calibration constant is in good agreement with the experimental results.

  12. Rapid Atmospheric-Pressure-Plasma-Jet Processed Porous Materials for Energy Harvesting and Storage Devices

    Directory of Open Access Journals (Sweden)

    Jian-Zhang Chen

    2015-01-01

    Full Text Available Atmospheric pressure plasma jet (APPJ technology is a versatile technology that has been applied in many energy harvesting and storage devices. This feature article provides an overview of the advances in APPJ technology and its application to solar cells and batteries. The ultrafast APPJ sintering of nanoporous oxides and 3D reduced graphene oxide nanosheets with accompanying optical emission spectroscopy analyses are described in detail. The applications of these nanoporous materials to photoanodes and counter electrodes of dye-sensitized solar cells are described. An ultrashort treatment (1 min on graphite felt electrodes of flow batteries also significantly improves the energy efficiency.

  13. Design of a 500-kJ Mather-type plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Heidarnia, A., E-mail: a-heidarnia@yahoo.com; Sadighzadeh, A.; Zaeem, A. A.; Damideh, V. [Nuclear Science and Technology Research Institute, Plasma Physics and Nuclear Fusion Research School (Iran, Islamic Republic of)

    2016-12-15

    In this article, design of a 500-kJ Mather-type plasma focus device to achieve 10{sup 11} neutrons/shot is reported. One of its important characteristics is the triple-part anode design. The anode is surrounded by an alumina insulator. The second part of the anode is changeable in order to locate cylindrical, conical, or other shapes of pieces mounted on it. This geometry leads to the easier investigation of the neutron and X-ray emissions of the device. The third part of the anode is for changing the materials exposed to different kinds of radiations. The design parameters are considered by semiempirical and empirical formulas and are sketched by Solidworks software. Also, the peak current and neutron yield are estimated.

  14. Design of a 500-kJ Mather-type plasma focus device

    Science.gov (United States)

    Heidarnia, A.; Sadighzadeh, A.; Zaeem, A. A.; Damideh, V.

    2016-12-01

    In this article, design of a 500-kJ Mather-type plasma focus device to achieve 1011 neutrons/shot is reported. One of its important characteristics is the triple-part anode design. The anode is surrounded by an alumina insulator. The second part of the anode is changeable in order to locate cylindrical, conical, or other shapes of pieces mounted on it. This geometry leads to the easier investigation of the neutron and X-ray emissions of the device. The third part of the anode is for changing the materials exposed to different kinds of radiations. The design parameters are considered by semiempirical and empirical formulas and are sketched by Solidworks software. Also, the peak current and neutron yield are estimated.

  15. Controlled cytotoxicity of plasma treated water formulated by open-air hybrid mode discharge

    Science.gov (United States)

    Lu, P.; Boehm, D.; Cullen, P.; Bourke, P.

    2017-06-01

    Plasma treated liquids (PTLs) provide a means to convey a broad range of effects of relevance for food, environmental, or clinical decontamination, plant growth promotion, and therapeutic applications. Devising the reactive species ingredients and controlling the biological response of PTLs are of great interest. We demonstrate an approach by using an open-air hybrid mode discharge (HMD) to control the principal reactive species composition within plasma treated water (PTW), which is then demonstrated to regulate the cytotoxicity of PTW. The cytotoxicity of HMD produced PTW demonstrates a non-monotonic change over the discharge time. Although hydrogen peroxide and nitrite are not the sole effectors for cell death caused by PTW, using them as principal reactive species indicators, cytotoxicity can be removed and/or enhanced by formulating their concentrations and composition through adjusting the discharge mode and time on-line during PTW generation without the addition of additional working gas or chemical scavengers. This work demonstrates that a hybrid mode discharge can be employed to generate a PTW formulation to control a biological response such as cytotoxicity. This provides insights into how plasma treated liquids may be harnessed for biological applications in a specific and controllable manner.

  16. Measurements of line-averaged electron density of pulsed plasmas using a He-Ne laser interferometer in a magnetized coaxial plasma gun device

    Science.gov (United States)

    Iwamoto, D.; Sakuma, I.; Kitagawa, Y.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    In next step of fusion devices such as ITER, lifetime of plasma-facing materials (PFMs) is strongly affected by transient heat and particle loads during type I edge localized modes (ELMs) and disruption. To clarify damage characteristics of the PFMs, transient heat and particle loads have been simulated by using a plasma gun device. We have performed simulation experiments by using a magnetized coaxial plasma gun (MCPG) device at University of Hyogo. The line-averaged electron density measured by a He-Ne interferometer is 2x10^21 m-3 in a drift tube. The plasma velocity measured by a time of flight technique and ion Doppler spectrometer was 70 km/s, corresponding to the ion energy of 100 eV for helium. Thus, the ion flux density is 1.4x10^26 m-2s-1. On the other hand, the MCPG is connected to a target chamber for material irradiation experiments. It is important to measure plasma parameters in front of target materials in the target chamber. In particular, a vapor cloud layer in front of the target material produced by the pulsed plasma irradiation has to be characterized in order to understand surface damage of PFMs under ELM-like plasma bombardment. In the conference, preliminary results of application of the He-Ne laser interferometer for the above experiment will be shown.

  17. Resonant excitation of waves by a spiraling ion beam on the large plasma device

    Science.gov (United States)

    Tripathi, Shreekrishna

    2015-11-01

    The resonant interaction between energetic-ions and plasma waves is a fundamental topic of importance in the space, controlled magnetic-fusion, and laboratory plasma physics. We report new results on the spontaneous generation of traveling shear Alfvén waves and high-harmonic beam-modes in the lower-hybrid range of frequencies by an intense ion beam. In particular, the role of Landau and Doppler-shifted ion-cyclotron resonances (DICR) in extracting the free-energy from the ion-beam and destabilizing Alfvén waves was explored on the Large Plasma Device (LAPD). In these experiments, single and dual-species magnetized plasmas (n ~1010 -1012 cm-3, Te ~ 5.0-10.0 eV, B = 0.6-1.8 kG, He+ and H+ ions, 19.0 m long, 0.6 m diameter) were produced and a spiraling hydrogen ion beam (5-15 keV, 2-10 A, beam-speed/Alfvén-speed = 0.2-1.5, J ~ 50-150 mA/cm2, pitch-angle ~53°) was injected into the plasma. The interaction of the beam with the plasma was diagnosed using a retarding-field energy analyzer, three-axis magnetic-loop, and Langmuir probes. The resonance conditions for the growth of shear Alfvén waves were examined by varying the parameters of the ion-beam and ambient plasma. The experimental results demonstrate that the DICR process is particularly effective in exciting left-handed polarized shear Alfvén waves that propagate in the direction opposite to the ion beam. The high-harmonic beam modes were detected in the vicinity of the spiraling ion beam and contained more than 80 harmonics of Doppler-shifted gyro-frequency of the beam. Work jointly supported by US DOE and NSF and performed at the Basic Plasma Science Facility, UCLA.

  18. Hundred joules plasma focus device as a potential pulsed source for in vitro cancer cell irradiation

    Science.gov (United States)

    Jain, J.; Moreno, J.; Andaur, R.; Armisen, R.; Morales, D.; Marcelain, K.; Avaria, G.; Bora, B.; Davis, S.; Pavez, C.; Soto, L.

    2017-08-01

    Plasma focus devices may arise as useful source to perform experiments aimed to study the effects of pulsed radiation on human cells in vitro. In the present work, a table top hundred joules plasma focus device, namely "PF-400J", was adapted to irradiate colorectal cancer cell line, DLD-1. For pulsed x-rays, the doses (energy absorbed per unit mass, measured in Gy) were measured using thermoluminescence detectors (TLD-100 dosimeters). The neutron fluence and the average energy were used to estimate the pulsed neutron doses. Fifty pulses of x-rays (0.12 Gy) and fifty pulses of neutrons (3.5 μGy) were used to irradiate the cancer cells. Irradiation-induced DNA damage and cell death were assessed at different time points after irradiation. Cell death was observed using pulsed neutron irradiation, at ultralow doses. Our results indicate that the PF-400J can be used for in vitro assessment of the effect of pulsed radiation in cancer cell research.

  19. Assessment of image quality in x-ray radiography imaging using a small plasma focus device

    Science.gov (United States)

    Kanani, A.; Shirani, B.; Jabbari, I.; Mokhtari, J.

    2014-08-01

    This paper offers a comprehensive investigation of image quality parameters for a small plasma focus as a pulsed hard x-ray source for radiography applications. A set of images were captured from some metal objects and electronic circuits using a low energy plasma focus at different voltages of capacitor bank and different pressures of argon gas. The x-ray source focal spot of this device was obtained to be about 0.6 mm using the penumbra imaging method. The image quality was studied by several parameters such as image contrast, line spread function (LSF) and modulation transfer function (MTF). Results showed that the contrast changes by variations in gas pressure. The best contrast was obtained at a pressure of 0.5 mbar and 3.75 kJ stored energy. The results of x-ray dose from the device showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. The measurements of LSF and MTF parameters were carried out by means of a thin stainless steel wire 0.8 mm in diameter and the cut-off frequency was obtained to be about 1.5 cycles/mm.

  20. 3D Modeling of Tracking Photovoltaic Devices Based on OpenGL%基于OpenGL的跟踪式光伏设备的三维建模

    Institute of Scientific and Technical Information of China (English)

    代冰辉; 高黄玮

    2014-01-01

    给出了一种利用OpenGL技术对跟踪式光伏设备进行三维建模的方法。首先分析跟踪式光伏设备的特征及运行方式,然后给出利用OpenGL进行跟踪式光伏设备三维建模的步骤,重点介绍利用三维变换矩阵函数对电池面板转动过程中边界角点坐标的计算方法,最后通过实验对某斜单轴跟踪式光伏设备进行了三维建模,并实现了电池面板上边界角点坐标的计算,为下一步跟踪式光伏设备的应用研究奠定基础。%A method is proposed to model and simulate tracking photovoltaic devices using the technology of OpenGL. First, this paper analyzes the features and operation mode of tracking photovoltaic devices, and then provides the steps of modeling tracking photovoltaic devices, meanwhile introduce the calculation method of solar cell panels ’coordinate by using 3D graphics transformation matrix function. In the end, the method realizes the simulation of the photovoltaic cell panels ’movement and the calculation of photovoltaic cell panel angular points’coordinate. The work of this paper lays foundation of the more application research of tracking photovoltaic devices.

  1. Understanding device-structure-induced variations in open-circuit voltage for organic photovoltaics.

    Science.gov (United States)

    Wang, Zhiping; Uemura, Yu; Zhou, Ying; Miyadera, Tetsuhiko; Azumi, Reiko; Yoshida, Yuji; Chikamatsu, Masayuki

    2015-05-27

    We investigate the structural influences on the device performance, especially on open-circuit voltage (V(OC)) in squaraine (SQ)/fullerene (C60) bilayer cells. Simply changing the SQ thickness could lead to 40% variation in V(OC) from 0.62 to 0.86 V. The ionization potential (IP) of SQ films and recombination at the anode surface as well as donor/acceptor (D/A) interface sensitively vary with film thicknesses, which account for the shifts in V(OC). The anode recombination can be effectively suppressed by preventing direct contact between C60 and the anode with a buffer layer, delivering an elevated V(OC). Through polarized infrared-multiple-angle incidence resolution spectroscopy measurement, the molecular structure of SQ films is found to gradually evolve from lying-down on indium-tin oxide substrates with noncentrosymmetric orientation at low thicknesses to random structure at high thicknesses. The different molecular orientation may yield different strengths of electronic coupling, which affects the charge-carrier recombination and thus V(OC). Moreover, the oriented SQ films would spontaneously compose aligned dipole moments at the D/A interface because of the strong dipolar effects in SQ molecules identified by density functional theory calculations, whereas no aligned interfacial dipole moment exists in the random structure. The resulting interfacial dipole moments would form an electric field at the D/A interface, leading to variations in the IP and thus impacting V(OC). Our findings demonstrate that V(OC) in organic photovoltaic cells is critically associated with the molecular orientation that affects the charge-carrier recombination and interfacial dipole alignment, which should be seriously taken into consideration for the design of organic molecules and optimization of the cell efficiency.

  2. Clinical results with the Trabectome, a novel surgical device for treatment of open-angle glaucoma.

    Science.gov (United States)

    Minckler, Don; Baerveldt, George; Ramirez, Marina Alfaro; Mosaed, Sameh; Wilson, Richard; Shaarawy, Tarek; Zack, Barend; Dustin, Laurie; Francis, Brian

    2006-01-01

    To describe treatment outcomes after Trabectome surgery in an initial series of 101 patients with open-angle glaucoma. A 19-gauge microelectrosurgical device enabled ab interno removal of a strip of trabecular meshwork and inner wall of Schlemm's canal under gonioscopic control with continual infusion and foot-pedal control of aspiration and electrosurgery. A smooth, pointed ceramic-coated insulating footplate was inserted into Schlemm's canal to act as a guide within the canal and to protect adjacent structures from mechanical or heat injury during ablation of a 30- to 90-degree arc of angle tissue. Mean preoperative intraocular pressure (IOP) in the initial 101 patients was 27.6 +/- 7.2 mm Hg. Thirty months postoperatively, mean IOP was 16.3 +/- 3.3 mm Hg (n = 11). The mean percentage drop over the whole course of follow-up was 40%. At all times postoperatively, the absolute and percent decrease in IOP from preoperative levels were statistically significant (paired t test, P < .0001). Overall success (IOP

  3. Investigation of the Effect of Plasma Polymerized Siloxane Coating for Enzyme Immobilization and Microfluidic Device Conception

    Directory of Open Access Journals (Sweden)

    Kalim Belhacene

    2016-12-01

    Full Text Available This paper describes the impact of a physical immobilization methodology, using plasma polymerized 1,1,3,3, tetramethyldisiloxane, on the catalytic performance of β-galactosidase from Aspergillus oryzae in a microfluidic device. The β-galactosidase was immobilized by a polymer coating grown by Plasma Enhanced Chemical Vapor Deposition (PEVCD. Combined with a microchannel patterned in the silicone, a microreactor was obtained with which the diffusion through the plasma polymerized layer and the hydrolysis of a synthetic substrate, the resorufin-β-d-galactopyranoside, were studied. A study of the efficiency of the immobilization procedure was investigated after several uses and kinetic parameters of immobilized β-galactosidase were calculated and compared with those of soluble enzyme. Simulation and a modelling approach were also initiated to understand phenomena that influenced enzyme behavior in the physical immobilization method. Thus, the catalytic performances of immobilized enzymes were directly influenced by immobilization conditions and particularly by the diffusion behavior and availability of substrate molecules in the enzyme microenvironment.

  4. Fast Three Dimensional Reconstruction of Magnetohydrodynamic Equilibria in Plasma Confinement Devices

    Science.gov (United States)

    Seal, S. K.; Cianciosa, M. R.; Hirshman, S. P.; Wingen, A.; Wilcox, R. S.; Unterberg, E. A.

    2016-10-01

    High-fidelity reconstruction of plasma equilibria in confinement devices like stellarators and tokamaks with external three dimensional (3D) fields is computationally very expensive and routinely requires days, even weeks, to complete using serial approaches. Here, we present the performance results of coupling the 3D plasma reconstruction code, V3FIT, with PARVMEC, the recently developed parallel version of VMEC. We present the parallel design of this coupled software along with a scalability analysis to identify its performance bottlenecks. Dependence of its scalability limits on model parameters is derived. These analyses are supported by scaling studies on over 6,000 processor cores of a Cray XC30 supercomputer. PARVMEC, which dominates the total runtime of the reconstruction procedure, is shown to deliver speedup improvements of over one to two orders of magnitude, depending on whether the equilibrium computations are carried out in a free or fixed boundary mode. The overall speedup of the coupled reconstruction code is shown to deliver over 40X improvement enabling fusion scientists to carry out high-fidelity 3D plasma reconstruction analyses in only a few hours instead of in days/weeks for the first time. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

  5. On the generation of magnetized collisionless shocks in the large plasma device

    Science.gov (United States)

    Schaeffer, D. B.; Winske, D.; Larson, D. J.; Cowee, M. M.; Constantin, C. G.; Bondarenko, A. S.; Clark, S. E.; Niemann, C.

    2017-04-01

    Collisionless shocks are common phenomena in space and astrophysical systems, and in many cases, the shocks can be modeled as the result of the expansion of a magnetic piston though a magnetized ambient plasma. Only recently, however, have laser facilities and diagnostic capabilities evolved sufficiently to allow the detailed study in the laboratory of the microphysics of piston-driven shocks. We review experiments on collisionless shocks driven by a laser-produced magnetic piston undertaken with the Phoenix laser laboratory and the Large Plasma Device at the University of California, Los Angeles. The experiments span a large parameter space in laser energy, background magnetic field, and ambient plasma properties that allow us to probe the physics of piston-ambient energy coupling, the launching of magnetosonic solitons, and the formation of subcritical shocks. The results indicate that piston-driven magnetized collisionless shocks in the laboratory can be characterized with a small set of dimensionless formation parameters that place the formation process in an organized and predictive framework.

  6. Formation of annular plasma downstream by magnetic aperture in the helicon experimental device

    Science.gov (United States)

    Ghosh, Soumen; Yadav, S.; Barada, K. K.; Chattopadhyay, P. K.; Ghosh, J.; Pal, R.; Bora, D.

    2017-02-01

    In the Helicon eXperimental (HeX) device, the geometric aperture is fixed, but the position of the magnetic aperture can be varied. Working with Argon gas in the pressure range of 1 - 10 × 10 - 4 mbar, an annular plasma (density ˜ 10 16 m - 3 ) is formed downstream, always in front of the magnetic aperture. This occurs irrespective of the relative position of the geometric aperture or the presence of a radial electric field. This is in contrary to the earlier proposition made by others that a radial electric field is necessary to produce a hollow plasma profile. Instead, the ionization of neutrals in the radially outer region by the tail electrons, rotating fast due to gradient-B drift in the azimuthal direction, seems to account for the observed off-axis density peaking in the present experiment. This also explains the variation of the plasma annulus diameter seen here by changing the input radio frequency power ( 100 - 800 W ) .

  7. Low Damage, High Anisotropy Inductively Coupled Plasma for Gallium Nitride based Devices

    KAUST Repository

    Ibrahim, Youssef H.

    2013-05-27

    Group III-nitride semiconductors possess unique properties, which make them versatile materials for suiting many applications. Structuring vertical and exceptionally smooth GaN profiles is crucial for efficient optical device operation. The processing requirements for laser devices and ridge waveguides are stringent as compared to LEDs and other electronic devices. Due to the strong bonding and chemically inert nature of GaN, dry etching becomes a critical fabrication step. The surface morphology and facet etch angle are analyzed using SEM and AFM measurements. The influence of different mask materials is also studied including Ni as well as a SiO2 and resist bilayer. The high selectivity Ni Mask is found to produce high sidewall angles ~79°. Processing parameters are optimized for both the mask material and GaN in order to achieve a highly anisotropic, smooth profile, without resorting to additional surface treatment steps. An optimizing a SF6/O2 plasma etch process resulted in smooth SiO2 mask sidewalls. The etch rate and GaN surface roughness dependence on the RF power was also examined. Under a low 2mTorr pressure, the RF and ICP power were optimized to 150W and 300W respectively, such that a smooth GaN morphology and sidewalls was achieved with reduced ion damage. The The AFM measurements of the etched GaN surface indicate a low RMS roughness ranging from 4.75 nm to 7.66 nm.

  8. Plasma process for development of a bulk heterojunction optoelectronic device: A highly sensitive UV detector

    Science.gov (United States)

    Sharma, Shyamalima; Pal, Arup R.; Chutia, Joyanti; Bailung, Heremba; Sarma, Neelotpal S.; Dass, Narendra N.; Patil, Dinkar

    2012-08-01

    Deposition of composite thin film of polyaniline/TiO2 (PAni/TiO2) has been carried out by a combined process of magnetron sputtering and plasma polymerization at a pressure of 5 × 10-2 Torr using titanium as a target material for sputtering, aniline as monomer, oxygen as reactive gas and argon as carrier gas/ion source for sputtering. The deposition has been achieved using direct current (dc) discharge power of 35 W for sputtering and radio frequency (rf) power of 8-12 W at substrate bias values in the ranges of -80 to -100 V for polymerization. The composition of the film has been studied using infrared spectroscopy, Raman spectroscopy as well as X-ray photoelectron spectroscopy. The morphology of the film has been characterized with the help of a transmission electron microscopy and atomic force microscopy. The ultraviolet (UV) photo-stability of the composite film has been studied by exposing the film deposited on silicon substrate for different reaction times up to 1 h under UV radiation at wave length range of 280-400 nm with an intensity of 0.4 mW/cm2. An organic/inorganic nanocomposite film based photovoltaic device has been developed. The device has an aluminum/composite/indium tin oxide sandwiched structure that shows strong photoresponse in ultraviolet region and hence the device has potential for application as an UV detector.

  9. Quasi-optical theory of microwave plasma heating in open magnetic trap

    Science.gov (United States)

    Shalashov, A. G.; Balakin, A. A.; Gospodchikov, E. D.; Khusainov, T. A.

    2016-11-01

    Microwave heating of a high-temperature plasma confined in a large-scale open magnetic trap, including all important wave effects like diffraction, absorption, dispersion, and wave beam aberrations, is described for the first time within the first-principle technique based on consistent Maxwell's equations. With this purpose, the quasi-optical approach is generalized over weakly inhomogeneous gyrotrotropic media with resonant absorption and spatial dispersion, and a new form of the integral quasi-optical equation is proposed. An effective numerical technique for this equation's solution is developed and realized in a new code QOOT, which is verified with the simulations of realistic electron cyclotron heating scenarios at the Gas Dynamic Trap at the Budker Institute of Nuclear Physics (Novosibirsk, Russia).

  10. Quasi-optical theory of microwave plasma heating in open magnetic trap

    CERN Document Server

    Shalashov, A G; Gospodchikov, E D; Khusainov, T A

    2016-01-01

    Microwave heating of a high-temperature plasma confined in a large-scale open magnetic trap, including all important wave effects like diffraction, absorption, dispersion and wave beam aberrations, is described for the first time within the first-principle technique based on consistent Maxwell's equations. With this purpose, the quasi-optical approach is generalized over weakly inhomogeneous gyrotrotropic media with resonant absorption and spatial dispersion, and a new form of the integral quasi-optical equation is proposed. An effective numerical technique for this equation's solution is developed and realized in a new code QOOT, which is verified with the simulations of realistic electron cyclotron heating scenarios at the Gas Dynamic Trap at the Budker Institute of Nuclear Physics (Novosibirsk, Russia).

  11. Reproducible Operating Margins on a 72800-Device Digital Superconducting Chip (Open Access)

    Science.gov (United States)

    2015-10-28

    Reproducible operating margins on a 72800- device digital superconducting chip Quentin P Herr, Joshua Osborne, Micah J A Stoutimore, Harold Hearne...super- conducting-quantum-interference- device circuits [6–8] and even more directly using magnetic imaging [9]. For larger, digital circuits, flux...design and test of reciprocal quantum logic shift-register yield vehicles consisting of up to 72 800 Josephson junction devices per die, the largest

  12. ELM-induced melting: assessment of shallow melt layer damage and the power handling capability of tungsten in a linear plasma device

    NARCIS (Netherlands)

    Morgan, T. W.; van Eden, G. G.; de Kruif, T. M.; van den Berg, M. A.; J Matejicek,; T Chraska,; De Temmerman, G.

    2014-01-01

    Tungsten samples were exposed to combined steady state and edge localised mode transient replication experiments in a linear plasma device; either in combined hydrogen plasma and high powered laser exposures at Magnum-PSI or steady state hydrogen plasma and superimposed plasma pulses created using a

  13. Plasma pro-atrial natriuretic peptide to estimate fluid balance during open and robot-assisted esophagectomy

    DEFF Research Database (Denmark)

    Strandby, Rune Broni; Ambrus, Rikard; Secher, Niels H

    2017-01-01

    BACKGROUND: It remains debated how much fluid should be administered during surgery. The atrial natriuretic peptide precursor proANP is released by atrial distension and deviations in plasma proANP are reported associated with perioperative fluid balance. We hypothesized that plasma proANP would...... decrease when the central blood volume is compromised during the abdominal part of robot-assisted hybrid (RE) esophagectomy and that a positive fluid balance would be required to maintain plasma proANP. METHODS: Patients undergoing RE (n = 25) or open (OE; n = 25) esophagectomy for gastroesophageal cancer...

  14. Low-Energy Plasma Focus Device as an Electron Beam Source

    Science.gov (United States)

    Seong Ling, Yap; Naresh Kumar, Nitturi; Lian Kuang, Lim; Chiow San, Wong

    2014-01-01

    A low-energy plasma focus device was used as an electron beam source. A technique was developed to simultaneously measure the electron beam intensity and energy. The system was operated in Argon filling at an optimum pressure of 1.7 mbar. A Faraday cup was used together with an array of filtered PIN diodes. The beam-target X-rays were registered through X-ray spectrometry. Copper and lead line radiations were registered upon usage as targets. The maximum electron beam charge and density were estimated to be 0.31 μC and 13.5 × 1016/m3, respectively. The average energy of the electron beam was 500 keV. The high flux of the electron beam can be potentially applicable in material sciences. PMID:25544952

  15. Low-Energy Plasma Focus Device as an Electron Beam Source

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair Khan

    2014-01-01

    Full Text Available A low-energy plasma focus device was used as an electron beam source. A technique was developed to simultaneously measure the electron beam intensity and energy. The system was operated in Argon filling at an optimum pressure of 1.7 mbar. A Faraday cup was used together with an array of filtered PIN diodes. The beam-target X-rays were registered through X-ray spectrometry. Copper and lead line radiations were registered upon usage as targets. The maximum electron beam charge and density were estimated to be 0.31 μC and 13.5×1016/m3, respectively. The average energy of the electron beam was 500 keV. The high flux of the electron beam can be potentially applicable in material sciences.

  16. Argon ion beam interaction on polyethylene terephthalate surface by a 4 kJ plasma focus device

    Indian Academy of Sciences (India)

    Habibi Morteza; Alavi M H S

    2016-03-01

    Polyethylene terephthalate (PET) has a wide variety of applications ranging from making regular bottles to biosensors. However, for many of these applications, surface treatment is needed to improve its surface characteristics such as adhesion to other materials. In this study, we focussed on treating PET foils by dense Ar pulsed plasma produced by a 4.5 kJ Mather-type plasmafocus device (20 kV, 40 $\\mu$f, 115 nH) to examine its ability to make the PET surface hydrophilic. The most common method to examine this characteristic is measuring the water contact angle on a polymer surface. The results show that while the energy and density of plasma in our device are higher compared to other devices, as the exposure time is very low, the device can enhance thewettability of PET film surfaces.

  17. Electrochromic Devices Deposited on Low-Temperature Plastics by Plasma-Enhanced Chemical Vapor Deposition

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, Joshua; Seman, Michael

    2005-09-20

    Electrochromic windows have been identified by the Basic energy Sciences Advisory committee as an important technology for the reduction of energy spent on heating and cooling in residential and commercial buildings. Electrochromic devices have the ability to reversibly alter their optical properties in response to a small electric field. By blocking ultraviolet and infrared radiation, while modulating the incoming visible radiation, electrochromics could reduce energy consumption by several Quads per year. This amounts to several percent of the total annual national energy expenditures. The purpose of this project was to demonstrate proof of concept for using plasma-enhanced chemical vapor deposition (PECVD) for depositing all five layers necessary for full electrochromic devices, as an alternative to sputtering techniques. The overall goal is to produce electrochromic devices on flexible polymer substrates using PECVD to significantly reduce the cost of the final product. We have successfully deposited all of the films necessary for a complete electrochromic devices using PECVD. The electrochromic layer, WO3, displayed excellent change in visible transmission with good switching times. The storage layer, V2O5, exhibited a high storage capacity and good clear state transmission. The electrolyte, Ta2O5, was shown to functional with good electrical resistivity to go along with the ability to transfer Li ions. There were issues with leakage over larger areas, which can be address with further process development. We developed a process to deposit ZnO:Ga with a sheet resistance of < 50 W/sq. with > 90% transmission. Although we were not able to deposit on polymers due to the temperatures required in combination with the inverted position of our substrates. Two types of full devices were produced. Devices with Ta2O5 were shown to be functional using small aluminum dots as the top contact. The polymer electrolyte devices were shown to have a clear state transmission of

  18. Nanofocus: an ultra-miniature dense pinch plasma focus device with submillimetric anode operating at 0.1 J

    Energy Technology Data Exchange (ETDEWEB)

    Soto, Leopoldo; Pavez, Cristian; Moreno, Jose [Comision Chilena de Energia Nuclear, Casilla 188-D, Santiago (Chile); Barbaglia, Mario; Clausse, Alejandro [CNEA-CONICET and Universidad Nacional del Centro, 7000 Tandil (Argentina)], E-mail: lsoto@cchen.cl

    2009-02-01

    As a method for investigating the minimum energy to produce a pinch plasma focus (PF) discharge, an ultra-miniature device for pinch discharges has been designed, constructed and characterized (nanofocus (NF): 5 nF, 5-10 kV, 5-10 kA, 60-250 mJ, 16 ns time to peak current). Submillimetric anode radii (0.8 and 0.21 mm) covered by coaxial insulators were used for experiments in hydrogen. Evidence of pinch was observed in electrical signals in discharges operating at 3 mbar and {approx}100 mJ. A single-frame image converter camera (4 ns exposure) was used to obtain plasma images in the visible range. The dynamics observed from the photographs is consistent with (a) the formation of a plasma sheath close to the insulator surface, (b) the plasma covering the anode, (c) radial compression over the anode; (d) finally the plasma is detached from the anode in the axial direction. The total time from stages (a) to (d) was observed in {approx}30 ns. This ultra-miniature device has a value for the 'plasma energy density parameter' and for the 'drive parameter' of the same order or greater than PF devices operating at energies several orders of magnitude higher.

  19. Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer

    Science.gov (United States)

    Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 μs. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

  20. Laser-driven, magnetized quasi-perpendicular collisionless shocks on the Large Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffer, D. B., E-mail: dschaeffer@physics.ucla.edu; Everson, E. T.; Bondarenko, A. S.; Clark, S. E.; Constantin, C. G.; Vincena, S.; Van Compernolle, B.; Tripathi, S. K. P.; Gekelman, W.; Niemann, C. [Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095 (United States); Winske, D. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-05-15

    The interaction of a laser-driven super-Alfvénic magnetic piston with a large, preformed magnetized ambient plasma has been studied by utilizing a unique experimental platform that couples the Raptor kJ-class laser system [Niemann et al., J. Instrum. 7, P03010 (2012)] to the Large Plasma Device [Gekelman et al., Rev. Sci. Instrum. 62, 2875 (1991)] at the University of California, Los Angeles. This platform provides experimental conditions of relevance to space and astrophysical magnetic collisionless shocks and, in particular, allows a detailed study of the microphysics of shock formation, including piston-ambient ion collisionless coupling. An overview of the platform and its capabilities is given, and recent experimental results on the coupling of energy between piston and ambient ions and the formation of collisionless shocks are presented and compared to theoretical and computational work. In particular, a magnetosonic pulse consistent with a low-Mach number collisionless shock is observed in a quasi-perpendicular geometry in both experiments and simulations.

  1. Performance study of microfluidic devices for blood plasma separation—a designer’s perspective

    Science.gov (United States)

    Tripathi, Siddhartha; Bala Varun Kumar, Y. V.; Prabhakar, Amit; Joshi, Suhas S.; Agrawal, Amit

    2015-08-01

    In this work, design and experiments on various blood plasma microdevices based on hydrodynamic flow separation techniques is carried out. We study their performance as a function of dependent governing parameters such as flow rate, feed hematocrit, and microchannel geometry. This work focuses on understanding separation phenomena in simple geometries; subsequently, individual simple geometrical parameters and biophysical effects are combined to fabricate hybridized designs, resulting in higher separation efficiencies. The distinctive features of our microfluidic devices are that they employ elevated dimensions (of the order of hundreds of microns), and thereby can be operated continuously over sufficient duration without clogging, while simplicity of fabrication makes them cost effective. The microdevices have been experimentally demonstrated over the entire range of hematocrit (i.e. from Hct 7% to Hct 45%). A high separation efficiency of about (78.34  ±  2.7)% with pure blood is achieved in our best hybrid design. We believe that the theory and experimental results presented in this study will aid designers and researchers working in the field of blood plasma separation microdevices.

  2. Design and implementation of virtual fault diagnosis system for photoelectric tracking devices based on OpenGL

    Science.gov (United States)

    Hou, MingLiang; Li, Cunhua; Zhang, Yong; Su, Liyun

    2009-10-01

    In view of the crucial deficiency of the traditional diagnosis approaches for photoelectric tracking devices and the output of more sufficient diagnosis information, in this paper, an virtual fault diagnosis system based on open graphic library(OpenGL) is proposed. Firstly, some interrelated key principles and technology of virtual reality, visualization and intelligent fault diagnosis technology are put forward. Then, the demand analysis and architecture of the system are elaborated. Next, details of interrelated essential implementation issues are also discussed, including the the 3D modeling of the related diagnosis equipments, key development process and design via OpenGL. Practical applications and experiments illuminate that the proposed approach is feasible and effective.

  3. Validation study of a drift-wave turbulence model for CSDX linear plasma device

    Science.gov (United States)

    Vaezi, P.; Holland, C.; Thakur, S. C.; Tynan, G. R.

    2017-09-01

    A validation study of self-regulating drift-wave turbulence/zonal flow dynamics in the Controlled Shear Decorrelation Experiment linear plasma device using Langmuir probe synthetic diagnostics is presented in this paper. We use a set of nonlocal 3D equations, which evolve density, vorticity, and electron temperature fluctuations, and include proper sheath boundary conditions. Nonlinear simulations of these equations are carried out using BOUndary Turbulence (BOUT++) framework. To identify the dominant parametric dependencies of the model, a linear growth rate sensitivity analysis is performed using input parameter uncertainties, which are taken from the experimental measurements. For the direct comparison of nonlinear simulation results to experiment, we use synthetic Langmuir probe diagnostics to generate a set of synthetic ion saturation current and floating potential fluctuations. In addition, comparisons of azimuthal velocities determined via time-delay estimation, and nonlinear energy transfer are shown. We observe a significant improvement of model-experiment agreement relative to the previous 2D simulations. An essential component of this improved agreement is found to be the effect of electron temperature fluctuations on floating potential measurements, which introduces clear amplitude and phase shifts relative to the plasma potential fluctuations in synthetically measured quantities, where the simulations capture the experimental measurements in the core of plasma. However, the simulations overpredict the fluctuation levels at larger radii. Moreover, systematic simulation scans show that the self-generated E × B zonal flows profile is very sensitive to the steepening of density equilibrium profile. This suggests that evolving both fluctuations and equilibrium profiles, along with the inclusion of modest axial variation of radial profiles in the model are needed for further improvement of simulation results against the experimental measurements.

  4. Dynamics of Fluctuations, Flows and Global Stability Under Electrode Biasing in a Linear Plasma Device

    Science.gov (United States)

    Desjardins, Tiffany

    2015-11-01

    Various bias electrodes have been inserted into the Helicon-Cathode (HelCat) device at the University of New Mexico, in order to affect intrinsic drift-wave turbulence and flows. The goal of the experiments was to suppress and effect the intrinsic turbulence and with detailed measurements, understand the changes that occur during biasing. The drift-mode in HelCat varies from coherent at low magnetic field (1kG). The first electrode consists of 6 concentric rings set in a ceramic substrate; these rings act as a boundary condition, sitting at the end of the plasma column 2-m away from the source. A negative bias has been found to have no effect on the fluctuations, but a positive bias (Vr>5Te) is required in order to suppress the drift-mode. Two molybdenum grids can also be inserted into the plasma and sit close to the source. Floating or grounding a grid results in suppressing the drift-mode of the system. A negative bias (>-5Te) is found to return the drift-mode, and it is possible to drive a once coherent mode into a broad-band turbulent one. From a bias voltage of -5Tenew mode, which is identified as a parallel-driven Kelvin-Helmholtz mode. At high positive bias, Vg>10Te, a new large-scale global mode is excited. This mode exhibits fluctuations in the ion saturation current, as well as in the potential, with a magnitude >50%. This mode has been identified as the potential relaxation instability (PRI). In order to better understand the modes and changes observed in the plasma, a linear stability code, LSS, was employed. As well, a 1D3V-PIC code utilizing Braginskii's equations was also utilized to understand the high-bias instability.

  5. Axial and radial preliminary results of the neutron radiation from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, J.; Silva, P.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first step of a program to design a repetitive pulsed neutron generator for applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Neutron emission has been obtained in both devices operating in deuterium. A specific technique was necessary to develop in order to detect neutron pulsed of 10{sup 4} neutrons per shot. The maximum total neutron yield measured was of the order of 10{sup 6} and 10{sup 4} neutrons per shot in the PF-400 J and PF-50 J respectively. Axial and radial measurements of the neutron emission are presented and the anisotropy is evaluated in this work. The neutrons are measured by pairs of silver activation counters, {sup 3}He detectors and scintillator-photomultiplier detectors. (authors)

  6. Acceleration of a Particle-in-Cell Code for Space Plasma Simulations with OpenACC

    Science.gov (United States)

    Peng, Ivy Bo; Markidis, Stefano; Vaivads, Andris; Vencels, Juris; Deca, Jan; Lapenta, Giovanni; Hart, Alistair; Laure, Erwin

    2015-04-01

    We simulate space plasmas with the Particle-in-cell (PIC) method that uses computational particles to mimic electrons and protons in solar wind and in Earth magnetosphere. The magnetic and electric fields are computed by solving the Maxwell's equations on a computational grid. In each PIC simulation step, there are four major phases: interpolation of fields to particles, updating the location and velocity of each particle, interpolation of particles to grids and solving the Maxwell's equations on the grid. We use the iPIC3D code, which was implemented in C++, using both MPI and OpenMP, for our case study. By November 2014, heterogeneous systems using hardware accelerators such as Graphics Processing Unit (GPUs) and the Many Integrated Core (MIC) coprocessors for high performance computing continue growth in the top 500 most powerful supercomputers world wide. Scientific applications for numerical simulations need to adapt to using accelerators to achieve portability and scalability in the coming exascale systems. In our work, we conduct a case study of using OpenACC to offload the computation intensive parts: particle mover and interpolation of particles to grids, in a massively parallel Particle-in-Cell simulation code, iPIC3D, to multi-GPU systems. We use MPI for inter-node communication for halo exchange and communicating particles. We identify the most promising parts suitable for GPUs accelerator by profiling using CrayPAT. We implemented manual deep copy to address the challenges of porting C++ classes to GPU. We document the necessary changes in the exiting algorithms to adapt for GPU computation. We present the challenges and findings as well as our methodology for porting a Particle-in-Cell code to multi-GPU systems using OpenACC. In this work, we will present the challenges, findings and our methodology of porting a Particle-in-Cell code for space applications as follows: We profile the iPIC3D code by Cray Performance Analysis Tool (CrayPAT) and identify

  7. Use of plasma "reconstitution" during cardio pulmonary bypass for a heart transplant after previous left ventricular assist device implant surgery.

    Science.gov (United States)

    Babaev, A; Saczkowski, R; Hynes, M; Boodhwani, M; Hudson, C C C

    2014-01-01

    The case report describes a novel technique of pre-emptive plasma "reconstitution" prior to disengagement from cardiopulmonary bypass (CPB) to minimize RV volume overload. The concomitant use of hemoconcentration facilitates volume and blood product management in cardiac transplant after previous left ventricular assist device implant surgery.

  8. Effect of seawater immersion on plasma osmotic pressure and electrolyte balance following open chest trauma

    Institute of Scientific and Technical Information of China (English)

    李辉; 鹿尔驯; 虞积耀; 王大鹏; 马聪

    2002-01-01

    To explore the effect of seawater immersion on serum osmotic pressure and electrolytes balance following chest trauma in dogs. Methods: Twenty-five healthy adult dogs were used in the experiment. A canine model of right open pneumothorax was established by chest puncturing on all animals. Animals were divided into three groups: a control group (n = 10) with chest trauma without any immersion;a seawater group ( n = 10) immersed in seawater after chest trauma and a normal saline group ( n = 5 ) immersed in normal saline solution following chest trauma. Blood samples were taken at different time intervals to determine plasma osmotic pressure and electrolytes. The hemodynamic changes were also recorded. Results: Mortality in the seawater group was much higher than that of the control group and the normal saline group. The mean survival time in the seawater group lasted only 45 minutes, while in the control group and the normal saline group the average survival time was more than 4 hours (P < 0.01 ). One of the most important causes of death was hypernatremia and high osmolality. Severe electrolytes imbalance was observed in seawater group.Hypernatremia and high osmolality were the most significant factors of high mortality in the seawater group. Conclusions: Seawater immersion after chest trauma appears to be associated with severe electrolyte imbalance as well as high osmotic pressure, These may be the risk factors leading to fatal outcome.

  9. Comparative study of radiation emission without and with target in a 2.2 kJ plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Muhammad Zubair, E-mail: mzubairkhan-um76@yahoo.com [Plasma Technology Research Center, Department of Physics, Faculty of Science, University Malaya, 50603 Kuala Lumpur Malaysia and Department of Physics, Federal Urdu University of Arts, Science and Technology, 45320 Islamabad (Pakistan); Ling, Yap Seong; San, Wong Chiow [Plasma Technology Research Center, Department of Physics, Faculty of Science, University Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-03-24

    The radiation emission in a 2.2 kJ Mather-type dense plasma focus device is investigated using a five channel BPX65 PIN diode spectrometer. Estimated X-ray associated with the hollow anode without and with target in Argon gas medium is compared. At optimum conditions, the radiation emission from the system is found to be strongly influenced with target in hollow anode and the filling gas pressure. The maximum X-ray yield in 4π sr was obtained in case of hollow anode in argon gas medium with target 'Lead' due to interaction of electron beam. Results indicated that an appropriate design of hollow anode with target could enhance the radiation emission by more intense interaction of expected electron beam with target. The outcomes are helpful in designing a plasma focus with enhanced X-ray radiation with improved shot to shot reproducibility in plasma focus device.

  10. Organic plasma process for simple and substrate-independent surface modification of polymeric BioMEMS devices.

    Science.gov (United States)

    Hiratsuka, Atsunori; Muguruma, Hitoshi; Lee, Kyong-Hoon; Karube, Isao

    2004-07-15

    A polymeric bio micro electromechanical systems (BioMEMS) device was fabricated using organic plasma polymerization, by which the surface of a polymeric substrate could easily be modified through vapor-phase deposition of organic thin films. This technique, capable of polymeric deposition of any kind of monomer, can serve the purpose of anti-fouling coating, wettability control, or layer-to-layer interface creation, on the surface of any given chemically-inert polymeric substrate without involving cumbersome surface organic reactions. A prototype device was fabricated to have an array of electrochemical glucose biosensors with the three electrode configuration, each of which has a microfluidic channel (500 microm x 800 microm) for capillary-action-driven sample delivery and the concerned enzymatic reaction. Stressing the advantages of the plasma polymerization process using a polymeric substrate together with some additional features accomplished in our device fabrication, new possibilities in the field of polymeric BioMEMS are discussed.

  11. Proceedings of US/Japan workshop, Q219 on high heat flux components and plasma surface interactions for next fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Ulrickson, M.A.; Stevens, P.L.; Hino, T.; Hirohata, Y. [eds.

    1996-12-01

    This report contains the viewgraphs from the proceedings of US/Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices. Some of the general topics covered by this report are: PFC/PSI in tokamak and helical devices; development of high heat flux components; PSIS and plasma facing materials;tritium; and material damage.

  12. OPEN

    DEFF Research Database (Denmark)

    Nickelsen, Anders; Paterno, Fabio; Grasselli, Agnese;

    2010-01-01

    One important aspect of ubiquitous environments is to provide users with the possibility to freely move about and continue to interact with the available applications through a variety of interactive devices such as cell phones, PDAs, desktop computers, intelligent watches or digital television...... and be controlled by the platform to enrich the user experience with the application. We describe the challenges following the centralisation of a migration platform that can support different types of applications, both games and business applications, implemented with either web-technologies or as component...

  13. Integration of augmented reality and assistive devices for post-stroke hand opening rehabilitation.

    Science.gov (United States)

    Luo, Xun; Kline, Tiffany; Fischer, Heidi; Stubblefield, Kathy; Kenyon, Robert; Kamper, Derek

    2005-01-01

    Impairment of hand function is prevalent among stroke survivors, motivating the search for effective rehabilitation therapy. Recent studies have suggested that for upper extremity functional recovery, repetitive training with virtual reality is helpful. Repetitive training can be facilitated with assistance from mechanical devices. Thus, we have developed a training environment that integrates augmented reality (AR) with assistive devices for post-stroke hand rehabilitation. The AR element of our environment utilizes head mounted display and virtual objects for reach-and-grasp task training. The assistive device consists of either a body-powered orthosis (BPO) or a pneumatic-powered device (PPD), both of which are incorporated into gloves. This environment can be easily set up and calibrated, is customizable for individual users, and requires active user participation. Additionally, it can be used with both real and virtual objects, as desired. We are currently conducting pilot case studies to assess ease of use and efficacy. At present, one stroke survivor from each of the three training conditions, AR-with-BPO, AR-with-PPD and AR-only (acting as the control), has completed the 6-week training paradigm. Preliminary findings suggest user acceptance of the technology and some potential for beneficial effects.

  14. Ultralow field emission from thinned, open-ended, and defected carbon nanotubes by using microwave hydrogen plasma processing

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jian-Hua, E-mail: jhdeng1983@163.com [College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Cheng, Lin; Wang, Fan-Jie; Yu, Bin; Li, Guo-Zheng; Li, De-Jun [College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Cheng, Guo-An [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China)

    2015-01-01

    Graphical abstract: Thinned, open-ended, and defected carbon nanotubes were prepared by using hydrogen plasma processing. The processed carbon nanotubes have far better field emission performance than that of the pristine ones. - Highlights: • CVD prepared CNT arrays were processed by microwave hydrogen plasma. • Thinned, open-ended, and defected CNTs were obtained. • Processed CNTs have far better field emission performance than the pristine ones. • Processed CNTs have applicable emission stability after being perfectly aged. - Abstract: Ultralow field emission is achieved from carbon nanotubes (CNTs) by using microwave hydrogen plasma processing. After the processing, typical capped CNT tips are removed, with thinned, open-ended, and defected CNTs left. Structural analyses indicate that the processed CNTs have more SP{sup 3}-hybridized defects as compared to the pristine ones. The morphology of CNTs can be readily controlled by adjusting microwave powers, which change the shape of CNTs by means of hydrogen plasma etching. Processed CNTs with optimal morphology are found to have an ultralow turn-on field of 0.566 V/μm and threshold field of 0.896 V/μm, much better than 0.948 and 1.559 V/μm of the as-grown CNTs, respectively. This improved FE performance is ascribed to the structural changes of CNTs after the processing. The thinned and open-ended shape of CNTs can facilitate electron tunneling through barriers and additionally, the increased defects at tube walls can serve as new active emission sites. Furthermore, our plasma processed CNTs exhibit excellent field emission stability at a large emission current density of 10.36 mA/cm{sup 2} after being perfectly aged, showing promising prospects in applications as high-performance vacuum electron sources.

  15. Paradigm shifts in plasma processing and application of fundamental kinetics to problems targeting 5 nm technology device technology

    Science.gov (United States)

    Chen, Lee

    2016-09-01

    It is often said that semiconductor technology is approaching the end of scaling. While fundamental device limits do approach, plasma etching has been doing the heavy lifting to supplement the basic limits in lithography. RF plasmas, pulsing in many forms, diffusion plasmas are but a few of the important developments over the last 20 years that have succeeded in the seemingly impossible tasks. The commonality of these plasmas is being self-consistent: their near-Boltzmann EEDf maintains ionization with its tail while providing charge-balance with its Te . To control the plasma chemistry is to control its EEDf; the entanglement of ionization with charge-balance in self-consistent plasmas places a constraint on the decoupling of plasma chemistry from ionization. Example like DC/RF parallel-plate hybridizes stochastic heating with DC-cathode injected e- -beam. While such arrangement offers some level of decoupling, it raised more questions than what it helped answered along the lines of beam-plasma instabilities, bounce-resonance ionization, etc. Pure e- -beam plasmas could be a drastic departure from the self-consistent plasmas. Examples like the NRL e- -beam system and the more recent TEL NEP (Nonambipolar e- Plasma) show strong decoupling of Te from ionization but it is almost certain, many more questions lurk: the functions connecting collisional relaxation with instabilities, the channels causing the dissociation of large fluorocarbons (controlling the ion-to- radical ratio), the production of the damaging deep UV in e- -beam plasmas, etc., and the list goes on. IADf is one factor on feature-profile and IEDf determines the surgical surface-excitation governing the selectivity, and both functions have Ti as the origin; what controls the e- -beam plasmas' Ti ? RF-bias has served well in applications requiring energetic excitation but, are there ways to improve the IEDf tightness? What are the adverse side-effects of ``improved IEDf''? Decades ago an infant RF-plasma

  16. A setup for measuring characteristics of microwave electric vacuum devices with open resonance structures

    DEFF Research Database (Denmark)

    Rybalko, Oleksandr; Ruban, A. I.; Vorob’ev, G. S.

    2015-01-01

    A new modification of the universal experimental setup for measuring electrodynamic characteristics of microwave generators with open resonance structures of the orotron–diffraction-radiation-generator type is described. To expand the functional capabilities and the electronic frequency-tuning ra...

  17. Open pit mine Drmno coal characteristics analysis for long-term thermo power plant supply regarding desulphurization device

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovic, V.; Jakovljevic, I.; Stepanovic, S.

    2010-07-01

    The Drmno deposit is located in the eastern part of the Kostolac coal basin of Serbia. This paper discussed the characteristics of the open pit Drmno coal mine for long-term thermo power plant supply regarding desulphurization device. The paper provided background information on the Drmno deposit, including geologic exploration; rock type; coal layers; and a systematization of characteristics of coal. Several charts and figures were presented, including the boundary of the Drmno open pit mine on the terrain and the roof of the coal seam; a map of combustible sulphur content in the third coal seam; and exploitative quality of coal exploitation periods. It was concluded that decreasing of the emissions of sulphur oxides from the thermal power plant will be one of the highest priority tasks of EPS. 3 refs., 2 tabs., 3 figs.

  18. QmeQ 1.0: An open-source Python package for calculations of transport through quantum dot devices

    DEFF Research Database (Denmark)

    Kiršanskas, Gediminas; Pedersen, Jonas Nyvold; Karlström, Olov

    2017-01-01

    QmeQ is an open-source Python package for numerical modeling of transport through quantum dot devices with strong electron–electron interactions using various approximate master equation approaches. The package provides a framework for calculating stationary particle or energy currents driven...... by differences in chemical potentials or temperatures between the leads which are tunnel coupled to the quantum dots. The electronic structures of the quantum dots are described by their single-particle states and the Coulomb matrix elements between the states. When transport is treated perturbatively to lowest...

  19. A continuous flow micro filtration device for plasma/blood separation using submicron vertical pillar gap structures

    Science.gov (United States)

    Kang, Tae Goo; Yoon, Yong-Jin; Ji, Hongmiao; Lim, Pei Yi; Chen, Yu

    2014-08-01

    This work demonstrates a continuous flow plasma/blood separator using a vertical submicron pillar gap structure. The working principle of the proposed separator is based on size exclusion of cells through cross-flow filtration, in which only plasma is allowed to pass through submicron vertical pillars located tangential to the main flow path of the blood sample. The maximum filtration efficiency of 99.9% was recorded with a plasma collection rate of 0.67 µl min-1 for an input blood flow rate of 12.5 µl min-1. The hemolysis phenomenon was observed for an input blood flow rate above 30 µl min-1. Based on the experimental results, we can conclude that the proposed device shows potential for the application of on-chip plasma/blood separation as a part of integrated point-of-care (POC) diagnostics systems.

  20. Integrated Prediction and Mitigation Methods of Materials Damage and Lifetime Assessment during Plasma Operation and Various Instabilities in Fusion Devices

    Energy Technology Data Exchange (ETDEWEB)

    Hassanein, Ahmed [Purdue Univ., West Lafayette, IN (United States)

    2015-03-31

    This report describes implementation of comprehensive and integrated models to evaluate plasma material interactions during normal and abnormal plasma operations. The models in full3D simulations represent state-of-the art worldwide development with numerous benchmarking of various tokamak devices and plasma simulators. In addition, significant number of experimental work has been performed in our center for materials under extreme environment (CMUXE) at Purdue to benchmark the effect of intense particle and heat fluxes on plasma-facing components. This represents one-year worth of work and resulted in more than 23 Journal Publications and numerous conferences presentations. The funding has helped several students to obtain their M.Sc. and Ph.D. degrees and many of them are now faculty members in US and around the world teaching and conducting fusion research. Our work has also been recognized through many awards.

  1. On the Role of Metastable Argon in Cold Atmospheric Pressure Plasma Jets with Shielding Gas Device

    Science.gov (United States)

    Schmidt-Bleker, Ansgar; Winter, Jorn; Sousa, Joao Santos; Puech, Vincent; Weltmann, Klaus-Dieter; Reuter, Stephan; ZIK plasmatis at the INP Greifswald e. V. Team; Laboratoire de Physique des Gaz et des Plasmas (LPGP), CNRS; Université Paris-Sud Team

    2014-10-01

    Shielding gas devices are a valuable tool for controlling the reactive species output of Cold Atmospheric Pressure Plasma (CAPP) Jets for biomedical applications. In this work we investigate the effect of different shielding gas compositions using a CAPP jet (kinpen) operated with argon. As shielding gas various mixtures of N2 and O2 are used. Metastable argon (Ar*) has been quantified using laser absorption spectroscopy and was identified as an important energy carrier in the CAPP jets effluent. The Ar* excitation dynamics was studied using phase resolve optical emission spectroscopy. Based on these findings a kinetic model for the gas phase chemistry has been developed that uses the Ar* density and dynamics as input and yields densities of O3, NO2, HNO2, HNO3, N2O5, H2O2 and N2O produced by the CAPP jet for different shielding gas compositions. The results are in good agreement with Fourier-Transform Infrared Spectroscopy measurements on these species. Authors gratefully acknowledge the funding by German Federal Ministry of Education a Research (BMBF) (Grant # 03Z2DN12).

  2. A new attempt using LabVIEW into a computational experiment of plasma focus device

    Science.gov (United States)

    Kim, Myungkyu

    2017-03-01

    The simulation program of plasma focus device based on S. Lee's model has been first developed since 30 years ago and it is widely used to date. Originally the program made by GWbasic language, and then modified by visual basic which was included in the Microsoft Excel. Using Excel well-known to researchers is a key advantage of this program. But it has disadvantages in displaying data in same graph, in slow calculation speed, and in displaying data and calculation of smaller time step. To overcome all these points, the LabVIEW that made by national instrument and based on graphical environment is used for simulation. Furthermore it is correlated with data acquisition of experiment, once experiment being the data is directly transferred to the simulation program and then analyzes and predicts for the next shot. The mass swept factor (fm) and current factor (fc) can be easily find out using this program. This paper describes the detail function and usage of the program and compares the results with the existing one.

  3. Development and experimental study of oil-free capacitor module for plasma focus device

    Science.gov (United States)

    Sharma, Ravindra Kumar; Sharma, Archana

    2017-03-01

    This development is concerned with the compact capacitor module for a plasma focus device. Oil-free, non-standard geometry capacitors are designed and developed for high current delivery in sub-microseconds time. Metalized dielectric film based pulse capacitor becomes progressively less viable at currents above 10 kA. It is due to reliability and energy scaling difficulties, based on effects such as vaporization, high resistivity, and end connection. Bipolar electrolytic capacitors are also not preferred due to their limited life and comparatively low peak current delivery. Bi-axially oriented polypropylene (BOPP) film with extended aluminum foil is a combination to deliver moderately high power. But, electrically weak points, relative permittivity, and the edge gap margins have made its adoption difficult. A concept has been developed in lab for implementing the above combination in a less complex and costly manner. This paper concerns the development and testing process techniques for quite different hollow cylindrical, oil-free capacitors (4 μ F , 10 kV, 20 nH). Shot life of 1000 has been experimentally performed on the test bed at its rated energy density level. The technological methods and engineering techniques are now available and utilized for manufacturing and testing of BOPP film based oil-free capacitors.

  4. Investigation of structural properties of chromium thin films prepared by a plasma focus device

    Science.gov (United States)

    Javadi, S.; Habibi, M.; Ghoranneviss, M.; Lee, S.; Saw, S. H.; Behbahani, R. A.

    2012-08-01

    We report the synthesis of chromium thin films on Si(400) substrates by utilizing a low-energy (1.6 kJ) plasma focus device. The films of chromium are deposited with different numbers of focus shots (15, 25 and 35) at a distance of 8 cm and at 0° angular position with respect to the anode axis. The films are investigated structurally by x-ray diffraction analysis and morphologically by atomic force microscopy and scanning electron microscopy. The elemental composition is characterized by energy dispersive x-ray analysis. Furthermore, Vicker's micro hardness is used to study the mechanical properties of the deposited films. The degree of crystallinity of chromium films, the size of the particles and the hardness values of the films increase when the number of focus shots is raised from 15 to 25 and then decrease when the substrate is treated with 35 shots. We discuss the dynamic processes involved in the formation of the chromium films.

  5. Novel atmospheric pressure plasma device releasing atomic hydrogen: reduction of microbial-contaminants and OH radicals in the air

    Science.gov (United States)

    Nojima, Hideo; Park, Rae-Eun; Kwon, Jun-Hyoun; Suh, Inseon; Jeon, Junsang; Ha, Eunju; On, Hyeon-Ki; Kim, Hye-Ryung; Choi, Kyoung Hui; Lee, Kwang-Hee; Seong, Baik-Lin; Jung, Hoon; Kang, Shin Jung; Namba, Shinichi; Takiyama, Ken

    2007-01-01

    A novel atmospheric pressure plasma device releasing atomic hydrogen has been developed. This device has specific properties such as (1) deactivation of airborne microbial-contaminants, (2) neutralization of indoor OH radicals and (3) being harmless to the human body. It consists of a ceramic plate as a positive ion generation electrode and a needle-shaped electrode as an electron emission electrode. Release of atomic hydrogen from the device has been investigated by the spectroscopic method. Optical emission of atomic hydrogen probably due to recombination of positive ions, H+(H2O)n, generated from the ceramic plate electrode and electrons emitted from the needle-shaped electrode have been clearly observed in the He gas (including water vapour) environment. The efficacy of the device to reduce airborne concentrations of influenza virus, bacteria, mould fungi and allergens has been evaluated. 99.6% of airborne influenza virus has been deactivated with the operation of the device compared with the control test in a 1 m3 chamber after 60 min. The neutralization of the OH radical has been investigated by spectroscopic and biological methods. A remarkable reduction of the OH radical in the air by operation of the device has been observed by laser-induced fluorescence spectroscopy. The cell protection effects of the device against OH radicals in the air have been observed. Furthermore, the side effects have been checked by animal experiments. The harmlessness of the device has been confirmed.

  6. Isolation of Circulating Plasma Cells in Multiple Myeloma Using CD138 Antibody-Based Capture in a Microfluidic Device

    Science.gov (United States)

    Qasaimeh, Mohammad A.; Wu, Yichao C.; Bose, Suman; Menachery, Anoop; Talluri, Srikanth; Gonzalez, Gabriel; Fulciniti, Mariateresa; Karp, Jeffrey M.; Prabhala, Rao H.; Karnik, Rohit

    2017-04-01

    The necessity for bone marrow aspiration and the lack of highly sensitive assays to detect residual disease present challenges for effective management of multiple myeloma (MM), a plasma cell cancer. We show that a microfluidic cell capture based on CD138 antigen, which is highly expressed on plasma cells, permits quantitation of rare circulating plasma cells (CPCs) in blood and subsequent fluorescence-based assays. The microfluidic device is based on a herringbone channel design, and exhibits an estimated cell capture efficiency of ~40-70%, permitting detection of <10 CPCs/mL using 1-mL sample volumes, which is difficult using existing techniques. In bone marrow samples, the microfluidic-based plasma cell counts exhibited excellent correlation with flow cytometry analysis. In peripheral blood samples, the device detected a baseline of 2-5 CD138+ cells/mL in healthy donor blood, with significantly higher numbers in blood samples of MM patients in remission (20-24 CD138+ cells/mL), and yet higher numbers in MM patients exhibiting disease (45-184 CD138+ cells/mL). Analysis of CPCs isolated using the device was consistent with serum immunoglobulin assays that are commonly used in MM diagnostics. These results indicate the potential of CD138-based microfluidic CPC capture as a useful ‘liquid biopsy’ that may complement or partially replace bone marrow aspiration.

  7. The pyrolytic-plasma method and the device for the utilization of hazardous waste containing organic compounds.

    Science.gov (United States)

    Opalińska, Teresa; Wnęk, Bartłomiej; Witowski, Artur; Juszczuk, Rafał; Majdak, Małgorzata; Bartusek, Stanilav

    2016-11-15

    This paper is focused on the new method of waste processing. The waste, including hazardous waste, contain organic compounds. The method consists in two main processes: the pyrolysis of waste and the oxidation of the pyrolytic gas with a use of non-equilibrium plasma. The practical implementation of the method requires the design, construction and testing of the new device in large laboratory scale. The experiments were carried out for the two kinds of waste: polyethylene as a model waste and the electronic waste as a real waste. The process of polyethylene decomposition showed that the operation of the device is correct because 99.74% of carbon moles contained in the PE samples was detected in the gas after the process. Thus, the PE samples practically were pyrolyzed completely to hydrocarbons, which were completely oxidized in the plasma reactor. It turned out that the device is useful for decomposition of the electronic waste. The conditions in the plasma reactor during the oxidation process of the pyrolysis products did not promote the formation of PCDD/Fs despite the presence of the oxidizing conditions. An important parameter determining the efficiency of the oxidation of the pyrolysis products is gas temperature in the plasma reactor.

  8. Spatial and Temporal characterization of plasma properties via emission spectroscopy in fusion materials testing device Proto-MPEX

    Science.gov (United States)

    Morean, Casey; Biewer, Theodore; Shaw, Guinevere; Beers, Josh; Ray, Holly

    2016-10-01

    The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) is a linear plasma source, and is intended to study plasma-material interactions (PMI) in conditions similar to those found in future fusion reactors. A high-resolution McPherson Czerny-Turner visible range spectrometer has been utilized to study the behavior of ions in the plasma. Analysis of the spectral lines, D_beta, D_gamma, and D_delta yields valuable information regarding the temperature and density of plasma ions at various locations along Proto-MPEX. Spectroscopic temperature and density measurements are compared to double Langmuir probe measurements to determine plasma behavior as a function of radius. Temporal and spatial measurements along the length of Proto-MPEX are constructed and compared to a photomultiplier tube based diagnostic manufactured at ORNL to determine the plasma's axial behavior along Proto-MPEX. Relative emission of beta, gamma, and delta lines are used to assess recycling effects in the device. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

  9. Magnetic shield for turbomolecular pump of the Magnetized Plasma Linear Experimental device at Saha Institute of Nuclear Physics.

    Science.gov (United States)

    Biswas, Subir; Chattopadhyay, Monobir; Pal, Rabindranath

    2011-01-01

    The turbo molecular pump of the Magnetized Plasma Linear Experimental device is protected from damage by a magnetic shield. As the pump runs continuously in a magnetic field environment during a plasma physics experiment, it may get damaged owing to eddy current effect. For design and testing of the shield, first we simulate in details various aspects of magnetic shield layouts using a readily available field design code. The performance of the shield made from two half cylinders of soft iron material, is experimentally observed to agree very well with the simulation results.

  10. Comparison of a new blood sampling device with the vacuum tube system for plasma and hematological analyses in healthy dogs.

    Science.gov (United States)

    Reynolds, Brice S; Boudet, Karine G; Faucher, Mathieu R; Geffre, Anne; Germain, Claude; Lefebvre, Hervé P

    2008-01-01

    Pediatric devices based on a capillary system may provide an alternative to vacuum tubes for canine blood sampling. The potential advantages are absence of vein collapse, limited blood volume sampled, and improved safety. The aim of this study was to compare routine plasma and hematological variables in seven healthy dogs using both techniques. Five biochemical analytes were measured, and a complete hematological examination and plasma exogenous creatinine clearance test were performed. No clinically relevant difference between the two techniques was observed for any variable or functional test assessed.

  11. Construction and experimental study of a 2.5 kJ, simply configured, Mather type plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Shirani, B.; Abbasi, F. [Shahid Beheshti University, Tehran (Iran, Islamic Republic of). Radiation Application Department

    2010-06-15

    In this work, a 2.5 kJ plasma focus device (named as SBUPF1) has been constructed on the basis of a simple configuration. The most important characteristics of this configuration is relative simplicity and using less components in its structure compared with common configurations. SBUPF1 has been tested between 18- 25 kV and wide range of pressure for various gases including Argon, Neon and Deuterium. The system shows consistent and reproducible plasma focusing action as well as fusion neutron production (when deuterium is used as working gas). (author)

  12. Wireless Electrical Device Using Open-Circuit Elements Having No Electrical Connections

    Science.gov (United States)

    Woodard, Stanley E. (Inventor); Taylor, Bryant Douglas (Inventor)

    2012-01-01

    A wireless electrical device includes an electrically unconnected electrical conductor and at least one electrically unconnected electrode spaced apart from the electrical conductor. The electrical conductor is shaped for storage of an electric field and a magnetic field. In the presence of a time-varying magnetic field, the electrical conductor so-shaped resonates to generate harmonic electric and magnetic field responses. Each electrode is at a location lying within the magnetic field response so-generated and is constructed such that a linear movement of electric charges is generated in each electrode due to the magnetic field response so-generated.

  13. [A device for measuring contamination of hands in work places with open radiation sources].

    Science.gov (United States)

    Husák, V; Kleinbauer, K; Erban, J

    1989-01-01

    The device manufactured is equipped with the NaI(Tl) scintillation crystal situated in a thick lead shielding. The cavity in the lead shielding allows inserting a hand which is in contact with the detector during the measurements. The apparatus exhibits low values of the minimum detectable superficial activity of radionuclides emitting low energy gamma-rays (e.g. 125I, 99mTc). The apparatus complies with the requirements for a sensitive and prompt monitoring the contamination of hands in departments of nuclear medicine with the numerous staff.

  14. EFFECTS OF ELECTROACUPUNCTURE ON PLASMA CATECHOLAMINE AND ANGIOTENSION Ⅱ IN OPEN HEART SURGICAL PATIENTS UNDERGOING CARDIOPULMONARY BYPASS

    Institute of Scientific and Technical Information of China (English)

    杨庆国; 杭燕南; 孙大金; 陈锡明; 王祥瑞; 许灿然; 姚建玲

    2001-01-01

    To study the effects of electroacupuncture on sympathetic adrenomedullary(SA) system and renin-an-giotensin-aldosterone (RAA) system in open heart surgical patients undergoing cardiopulmonary bypass (CPB), 30 patients with atrial septal defect were randomly divided into general anesthesia (GA) group, acupuncture anesthesia (AA) group and acupuncture with general anesthesia (AGA) group. Peripheral blood samples were taken before anesthesia and 30 min after CPB. The plasma concentrations of norepinephrine (NE), epinphrine (E) and angiotensin Ⅱ (AⅡ) were detected. Results: Plasma NE and E of post-CPB increased significantly in GA group and AA group, but decreased significantly in AGA group. Plasma A Ⅱ of post-CPB increased significantly in GA group, but no marked changes were found in AA group and AGA group. Conclusions: Acupuncture can improve the A Ⅱ response to cardiac surgery and CPB. AGA but not AA can inhibit the catecholamine (CA) response to cardiac surgery and CPB.

  15. Clinical trial results of a modified gore excluder endograft: comparison with open repair and original device design.

    Science.gov (United States)

    Curci, John A; Fillinger, Mark F; Naslund, Thomas C; Rubin, Brian G

    2007-05-01

    A multicenter phase II clinical trial of aneurysm treatment was performed with the modified Gore Excluder bifurcated endoprosthesis (m-EBE, n = 193) and compared with previously reported results from the same group of the original unmodified device (EBE, n = 253) or standard open aneurysm exclusion (control, n = 99). Graft modifications were primarily related to the proximal attachment site and included an increase in the length of the external expanded polytetrafluoroethylene and modifications of the anchor configuration. Preprocedural characteristics, periprocedural clinical events, and postprocedural clinical and radiographic follow-up at 1, 6, 12, and 24 months were analyzed with univariate and multivariate statistics. Device placement was successful in all cases, and there were no aneurysm ruptures in any group. Survival to 2 years was similar in all groups. Early major adverse events with the m-EBE were similar to those with the EBE (14.5% vs. 14%, P = 0.9) and markedly reduced compared to the control group (60.6%, P EBE (2% vs. 6% with the EBE, P EBE compared to the EBE during 14- to 28-month follow-up (15.6% vs. 24.9%, P = 0.037), in part due to the difference in reinterventions. The safety and efficacy of the m-EBE are statistically similar to the original device, although there was a reduction in major late adverse events between the two iterations of the endograft. This difference appears to be related to increased operator experience and changing treatment algorithms. Compared with open aneurysm repair, endoluminal repair with the m-EBE offers advantages in the reduction of early major adverse events while maintaining similar survival and rupture-free outcomes in the intermediate term.

  16. Effect of molar intrusion with temporary anchorage devices in patients with anterior open bite: a systematic review

    Directory of Open Access Journals (Sweden)

    Ahmad Saleem Alsafadi

    2016-03-01

    Full Text Available Abstract Objective The objective of the study is to assess the effect of molar intrusion with temporary anchorage devices on the vertical facial morphology and mandibular rotation during open bite treatment in the permanent dentition. Methods We performed a systematic review of the published data in seven electronic databases up to September 2015. We considered studies for inclusion if they were examining the effects of posterior teeth intrusion on the vertical facial morphology with open bite malocclusion in the permanent dentition. Study selection, risk of bias assessment, and data-extraction were performed in duplicate. Meta-analysis was not possible due to dissimilarity and heterogeneity among the included studies. Results Out of the 42 articles that met the initial eligibility criteria, 12 studies were finally selected. Low level of scientific evidence was identified after risk of bias assessment of the included studies with no relevant randomized controlled trial performed. Out of the 12 selected studies, five studies used miniplates and seven studies used miniscrews. Mandibular counterclockwise rotation was found to be between 2.3° and 3.9° in six studies (as sassed by mandibular plane angle, between MeGo or GoGn and SN or FH plane while it was less than 2° in the remaining studies. Conclusions Current weak evidence suggests that molar intrusion with temporary anchorage devices may cause mandibular counterclockwise autorotation. Future well-conducted and clearly reported multicenter randomized controlled trials that include a non-treatment control group are needed to make robust recommendations regarding the amount of mandibular rotation during open bite treatments.

  17. Development of a double plasma gun device for investigation of effects of vapor shielding on erosion of PFC materials under ELM-like pulsed plasma bombardment

    Science.gov (United States)

    Sakuma, I.; Iwamoto, D.; Kitagawa, Y.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    It is considered that thermal transient events such as type I edge localized modes (ELMs) could limit the lifetime of plasma-facing components (PFCs) in ITER. We have investigated surface damage of tungsten (W) materials under transient heat and particle loads by using a magnetized coaxial plasma gun (MCPG) device at University of Hyogo. The capacitor bank energy for the plasma discharge is 144 kJ (2.88 mF, 10 kVmax). Surface melting of a W material was clearly observed at the energy density of ˜2 MJ/m2. It is known that surface melting and evaporation during a transient heat load could generate a vapor cloud layer in front of the target material [1]. Then, the subsequent erosion could be reduced by the vapor shielding effect. In this study, we introduce a new experiment using two MCPG devices (MCPG-1, 2) to understand vapor shielding effects of a W surface under ELM-like pulsed plasma bombardment. The capacitor bank energy of MCPG-2 is almost same as that of MCPG-1. The second plasmoid is applied with a variable delay time after the plasmoid produced by MCPG-1. Then, a vapor cloud layer could shield the second plasma load. To verify the vapor shielding effects, surface damage of a W material is investigated by changing the delay time. In the conference, the preliminary experimental results will be shown.[4pt] [1] A. Hassanein et al., J. Nucl. Mater. 390-391, pp. 777-780 (2009).

  18. Plasma sputtering robotic device for in-situ thick coatings of long, small diameter vacuum tubesa)

    Science.gov (United States)

    Hershcovitch, A.; Blaskiewicz, M.; Brennan, J. M.; Custer, A.; Dingus, A.; Erickson, M.; Fischer, W.; Jamshidi, N.; Laping, R.; Liaw, C.-J.; Meng, W.; Poole, H. J.; Todd, R.

    2015-05-01

    A novel robotic plasma magnetron mole with a 50 cm long cathode was designed, fabricated, and operated. The reason for this endeavor is to alleviate the problems of unacceptable resistive heating of stainless steel vacuum tubes in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase the cathode lifetime, a movable magnet package was developed, and the thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5 cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3 cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced secondary electron yield to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that a 10 μm copper coated stainless steel RHIC tube has a conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. The device details and experimental results are described.

  19. Plasma Sputtering Robotic Device for In-Situ Thick Coatings of Long, Small Diameter Vacuum Tubes

    Science.gov (United States)

    Hershcovitch, Ady

    2014-10-01

    A novel robotic plasma magnetron mole with a 50 cm long cathode was designed fabricated & operated. Reason for this endeavor is to alleviate the problems of unacceptable ohmic heating of stainless steel vacuum tubes and of electron clouds, due to high secondary electron yield (SEY), in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase cathode lifetime, movable magnet package was developed, and thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5 cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3 cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced SEY to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that 10 μm Cu coated stainless steel RHIC tube has conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. Device detail and experimental results will be presented. Work supported by Brookhaven Science Associates, LLC under

  20. Plasma sputtering robotic device for in-situ thick coatings of long, small diameter vacuum tubes

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, A., E-mail: hershcovitch@bnl.gov; Blaskiewicz, M.; Brennan, J. M.; Fischer, W.; Liaw, C.-J.; Meng, W.; Todd, R. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Custer, A.; Dingus, A.; Erickson, M.; Jamshidi, N.; Laping, R.; Poole, H. J. [PVI, Oxnard, California 93031 (United States)

    2015-05-15

    A novel robotic plasma magnetron mole with a 50 cm long cathode was designed, fabricated, and operated. The reason for this endeavor is to alleviate the problems of unacceptable resistive heating of stainless steel vacuum tubes in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase the cathode lifetime, a movable magnet package was developed, and the thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5 cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3 cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced secondary electron yield to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that a 10 μm copper coated stainless steel RHIC tube has a conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. The device details and experimental results are described.

  1. A spectral line survey from 17.5-250 nm of plasmas created in a magnetic confinement device

    Science.gov (United States)

    McCarthy, K. J.; Zurro, B.; Hollmann, E. M.; Hernández Sánchez, J.; TJ-II Team1, the

    2016-11-01

    Spectral emission lines continue to be a powerful tool for studying astrophysical, process, laser-produced, and magnetically confined plasmas, among others. Hence, numerous spectroscopy-based plasma diagnostics, from the x-ray to the infrared, make use of the relative intensity, width, displacement in wavelength, or temporal evolution of such emission lines emitted by the atoms and ions present in such plasmas. In this work, a spectral line survey, from 17.5-250 nm, is presented for electron cyclotron resonance heated (ECRH) and neutral beam injection (NBI) heated plasmas created and maintained in the TJ-II stellarator, a medium-sized magnetically confined plasma device. In these plasmas, for which hydrogen, deuterium or helium have been used as the working gas, central electron temperatures and densities up to 1 keV and 5 × 1019 m-3, respectively, are achieved. This work is a compilation of the identified spectral emission lines emitted by the working gas as well by the intrinsic and injected impurity ions in the above wavelength range. For this, spectra were recorded, over the past fifteen years of TJ-II operation, using a 1 m focal length normal incidence spectrometer equipped with a charge-coupled detector at its output focal plane. In total, almost 400 spectral emission lines from eighteen different elements have been identified using a number of atomic line emission databases.

  2. The pyrolytic-plasma method and the device for the utilization of hazardous waste containing organic compounds

    OpenAIRE

    Opalińska, Teresa; Wnęk, Bartłomiej; Witowski, Artur; Juszczuk, Rafał; Majdak, Małgorzata; Bartusek, Stanislav

    2016-01-01

    This paper is focused on the new method of waste processing. The waste, including hazardous waste, contain organic compounds. The method consists in two main processes: the pyrolysis of waste and the oxidation of the pyrolytic gas with a use of non-equilibrium plasma. The practical implementation of the method requires the design, construction and testing of the new device in large laboratory scale. The experiments were carried out for the two kinds of waste: polyethylene as a model waste and...

  3. Enhancing the plasma illumination behaviour of microplasma devices using microcrystalline/ultra-nanocrystalline hybrid diamond materials as cathodes.

    Science.gov (United States)

    Chang, Tinghsun; Lou, Shiucheng; Chen, Huangchin; Chen, Chulung; Lee, Chiyoung; Tai, Nyanhwa; Lin, Inan

    2013-08-21

    The properties of capacity-type microplasma devices were significantly enhanced due to the utilisation of hybrid diamond films as cathodes. The performance of the microplasma devices was closely correlated with the electron field emission (EFE) properties of the diamond cathode materials. The nanoemitters, which were prepared by growing duplex-structured diamond films [microcrystalline diamond (MCD)/ultra-nanocrystalline diamond (UNCD)] on Si-pyramid templates via a two-step microwave plasma enhanced chemical vapour deposition (MPE-CVD) process, exhibited improved EFE properties (E0 = 5.99 V μm(-1), J(e) = 1.10 mA cm(-2) at 8.50 V μm(-1) applied field), resulting in superior microplasma device performance (with a lower threshold field of 200 V mm(-1) and a higher plasma current density of 7.80 mA cm(-2)) in comparison with UNCD film devices prepared using a single-step MPE-CVD process. The superior EFE properties of the duplex-structured MCD-UNCD films relative to those of the UNCD films can be attributed to the unique granular structure of the diamond films. High-resolution transmission electron microscopy reveals that the MCD-UNCD films consisted of abundant graphitic phases located at the periphery of large diamond aggregates and at the boundaries between the ultra-small diamond grains. The presence of the graphite phase is presumed to be the prime factor that renders these films more conductive and causes these films to exhibit higher EFE properties, thus resulting in the improved plasma illumination properties of the microplasma devices.

  4. Elevated Plasma Endothelin-1 Levels in Normal Tension Glaucoma and Primary Open-Angle Glaucoma: A Meta-Analysis

    Science.gov (United States)

    Li, Shengjie; Zhang, Aiping

    2016-01-01

    Purpose. The aim of this meta-analysis was to clarify the association between the plasma endothelin-1 level and the risks of normal tension glaucoma (NTG) and primary open-angle glaucoma (POAG). Methods. Relevant publications were collected from three databases including PubMed, EMBASE, and the Web of Science through December 31, 2015. In this study, the terms “(endothelin OR ET) AND glaucoma” were searched. Review Manager 5.2 was used to process the data. Results. Seven studies (212 cases, 164 controls) were included for the NTG analysis. The mean plasma endothelin-1 level in the NTG subjects was 0.60 pg/mL (p = 0.02, 95% CI: 0.17–1.04) higher than that of the healthy controls. Six studies (160 cases, 174 controls) were included for the POAG analysis, and the endothelin-1 level was 0.63 pg/mL (p = 0.007, 95% CI: 0.12–1.15) higher in the POAG subjects than in the healthy controls. Additionally, two studies influenced the meta-analysis results regarding the association of plasma endothelin-1 with POAG by sensitivity analysis, and the probability of publication bias was low. Conclusions. The observation that NTG and POAG subjects showed significantly elevated endothelin-1 plasma concentrations suggests that a higher plasma level of endothelin-1 might increase the risk of NTG and POAG development. PMID:27965889

  5. Association of NT-proANP Level in Plasma and Humor Aqueous with Primary Open-Angle Glaucoma.

    Science.gov (United States)

    Baumane, Kristine; Ranka, Renate; Laganovska, Guna

    2017-02-01

    The aim of this study is to determine differences in the levels of NT-proANP in the plasma and aqueous humor of glaucoma and cataract patients and to evaluate whether any relationships are present. The study group consisted of 58 patients with primary-open glaucoma (POAG) undergoing trabeculectomy surgery. The control group was comprised of 32 age-matched cataract patients. The concentration of the N-terminal fragment of the proatrial natriuretic peptide (NT-proANP, 1-98) in the aqueous humor and blood plasma samples was measured using an immunochemical method (ELISA). The plasma NT-proANP concentration was significantly increased in patients with POAG compared to that in the control group (7.00 vs. 4.65 nmol/L, P = 0.0054). Similarly, the NT-proANP concentration in the aqueous humor was significantly higher in the POAG patients (0.47 vs. 0.09 nmol/L, P = 0.0112). However, there was no correlation between the NT-proANP values in the aqueous humor and the plasma of the POAG patients, as well as between the NT-proANP values in the aqueous humor and the intraocular pressure. We identified an association between the levels of NT-proANP in the plasma and the aqueous humor with POAG. Our data support the idea of the involvement of NP system in the development of POAG and highlight ANP as a possible biomarker of glaucoma.

  6. Demonstration of neutron production in a table-top pinch plasma focus device operating at only tens of joules

    Energy Technology Data Exchange (ETDEWEB)

    Soto, Leopoldo; Silva, Patricio; Moreno, Jose; Zambra, Marcelo; Pavez, Cristian [Comision Chilena de EnergIa Nuclear, Casilla 188-D, Santiago (Chile); Kies, Walter; Altamirano, Luis; Huerta, Luis [Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile); Mayer, Roberto E [Centro Atomico Bariloche and Instituto Balseiro, 8400 Bariloche (Argentina); Clausse, Alejandro [CNEA-CONICET and Universidad Nacional del Centro, 7000 Tandil (Argentina)], E-mail: lsoto@cchen.cl

    2008-10-21

    Neutron emission from a deuterium plasma pinch generated in a very small plasma focus (6 mm anode diameter) operating at only tens of joules is presented. A maximum current of 50 kA is achieved 140 ns after the beginning of the discharge, when the device is charged at 50 J (160 nF capacitor bank, 38 nH, 20-30 kV, 32-72 J). Although the stored energy is very low, the estimated energy density in the plasma and the energy per particle in the plasma are of the same order as in higher energy devices. The dependence of the neutron yield on the filling pressure of deuterium was obtained for discharges with 50 and 67 J stored in the capacitor bank. Neutrons were measured by means of a system based on a {sup 3}He proportional counter in current mode. The average neutron yield for 50 J discharges at 6 mbar was (1.2 {+-} 0.5) x 10{sup 4} neutrons per shot, and (3.6 {+-} 1.6) x 10{sup 4} for 67 J discharges at 9 mbar. The maximum energy of the neutrons was (2.7 {+-} 1.8) MeV. Possible applications related to substance detection and others are discussed.

  7. Pretreatment of plasma samples by a novel hollow fiber centrifugal ultrafiltrate device for the determination of cefaclor concentrations in human plasma.

    Science.gov (United States)

    Li, Jun-Mei; Li, Cen; Jiang, Ye; Ren, Shu-Meng

    2010-10-29

    A simple sample preparation method was developed by using a centrifugal ultrafiltration (CF-UF) device with hollow fiber (HF) for the determination of cefaclor in plasma by HPLC. Samples were placed into a homemade device, which was consisted of a glass tube and a U-shaped hollow fiber. The filtrate was withdrawn from the hollow fiber into a syringe after centrifugation and 20 μL was directly injected into the HPLC for analysis. The HPLC method had a linear calibration curve in the concentration range of 6.00×10(-2)-30.7 μg mL(-1)(r=0.9996). The limit of detection (LOD) and limit of quantitation (LOQ) were 0.02 and 0.06 μg mL(-1), respectively. The intra and inter-day precisions (RSD) were 1.7%, 1.2%, 1.0% and 3.6%, 2.5%, 1.9%, respectively, for three concentrations. Assay accuracy was higher than 99.2% and the absolute recovery was 86.8-92.5%. It is feasible to use this novel and low cost device for sample pretreatment for the analysis of cefaclor in plasma.

  8. Integration of soft tissue model and open haptic device for medical training simulator

    Science.gov (United States)

    Akasum, G. F.; Ramdhania, L. N.; Suprijanto; Widyotriatmo, A.

    2016-03-01

    Minimally Invasive Surgery (MIS) has been widely used to perform any surgical procedures nowadays. Currently, MIS has been applied in some cases in Indonesia. Needle insertion is one of simple MIS procedure that can be used for some purposes. Before the needle insertion technique used in the real situation, it essential to train this type of medical student skills. The research has developed an open platform of needle insertion simulator with haptic feedback that providing the medical student a realistic feel encountered during the actual procedures. There are three main steps in build the training simulator, which are configure hardware system, develop a program to create soft tissue model and the integration of hardware and software. For evaluating its performance, haptic simulator was tested by 24 volunteers on a scenario of soft tissue model. Each volunteer must insert the needle on simulator until rearch the target point with visual feedback that visualized on the monitor. From the result it can concluded that the soft tissue model can bring the sensation of touch through the perceived force feedback on haptic actuator by looking at the different force in accordance with different stiffness in each layer.

  9. Theoretical investigation of the open circuit voltage: P3HT/9,9'-bisfluorenylidene derivative devices.

    Science.gov (United States)

    Carlotto, Silvia

    2014-07-03

    The calculation of the power conversion efficiency (PCE) value for a bulk heterojunction (BHJ) organic solar cell is complex due to the wide number of parameters involved in the processes. This study focuses the attention on the molecular parameters involved into the open circuit voltage and the PCE definitions and in particular on the electronic coupling and on the lowest unoccupied molecular orbital (LUMO) of the acceptor. A simplified model system composed by a polymer as donor and a novel class of molecules (9,9'-bisfluorenylidene derivatives) as acceptor has been proposed as prototype to simulate the BHJ organic solar cell interface. Several substituents on different positions are tested and the chemical nature/position of substituents have a relevant influence on the electronic coupling and energy level values. Geometrical and electronic properties are obtained using density functional theory (DFT) and time-dependent (TD)-DFT calculations, respectively. A new hypothesis suggests that the minimization of the electronic coupling between the LUMO of the acceptor and the highest occupied molecular orbital (HOMO) of the donor can enhance the PCE reducing the recombination interface processes and calculations showing the possibility to minimize this parameter and fine-tune acceptor energy level through the acceptor functionalization. An accurate balance between electronic coupling and on the LUMO of the acceptor allows to propose the more performing candidate as electron acceptor in a P3HT/99'BF derivative BHJ solar cell.

  10. PREFACE: 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and 21st IAEA TM on Research Using Small Fusion Devices (RUSFD)

    Science.gov (United States)

    Iván Vargas-Blanco, V.; Herrera-Velázquez, J. Julio E.

    2015-03-01

    Written contributions from participants of the Joint 15th Latin American Workshop on Plasma Physics (LAWPP 2014) - 21st IAEA Technical Meeting on Research Using Small Fusion Devices (21st IAEA TM RUSFD). The International Advisory Committees of the 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and the 21st IAEA TM on Research Using Small Fusion Devices (RUSFD), agreed to carry out together this Joint LAWPP 2014 - 21st RUSFD in San José, Costa Rica, on 27-31 January 2014. The Joint LAWPP 2014 - 21st RUSFD meeting, organized by the Instituto Tecnológico de Costa Rica, Universidad Nacional de Costa Rica, and Ad Astra Rocket Company in collaboration with the International Atomic Energy Agency (IAEA). The Latin American Workshop on Plasma Physics (LAWPP) is a series of events which has been held periodically since 1982, with the purpose of providing a forum in which the research of the Latin American plasma physics community can be displayed, as well as fostering collaborations among plasma scientists within the region and with researchers from the rest of the world. Recognized plasma scientists from developed countries are specially invited to the meeting to present the state of the art on several "hot" topics related to plasma physics. It is an open meeting, with an International Advisory Committee, in which the working language is English. It was firstly held in 1982 in Cambuquira, Brazil, followed by workshops in Medellín, Colombia (1985), Santiago de Chile, Chile (1988), Buenos Aires, Argentina (1990), Mexico City, Mexico (1992), Foz do Iguaçu, Brazil (1994, combined with the International Congress on Plasma Physics (ICPP)), Caracas, Venezuela (1997), Tandil, Argentina (1998), La Serena, Chile (2000), Sao Pedro, Brazil (2003), Mexico City, Mexico (2005), Caracas, Venezuela (2007), Santiago de Chile, Chile (2010, combined with the ICPP) and Mar de Plata, Argentina (2011). The 21st IAEA TM on Research Using Small Fusion Devices is an ideal forum for

  11. Control of Beam Energy and Flux Ratio in an Ion-Beam-Background Plasma System Produced in a Double Plasma Device

    Science.gov (United States)

    Wei, Zian; Ma, Jinxiu; Li, Yuanrui; Sun, Yan; Jiang, Zhengqi

    2016-11-01

    Plasmas containing ion beams have various applications both in plasma technology and in fundamental research. The ion beam energy and flux are the two factors characterizing the beam properties. Previous studies have not achieved the independent adjustment of these two parameters. In this paper, an ion-beam-background-plasma system was produced with hot-cathode discharge in a double plasma device separated by two adjacent grids, with which the beam energy and flux ratio (the ratio between the beam flux and total ion flux) can be controlled independently. It is shown that the discharge voltage (i.e., voltage across the hot-cathode and anode) and the voltage drop between the two separation grids can be used to effectively control the beam energy while the flux ratio is not affected by these voltages. The flux ratio depends sensitively on hot-filaments heating current whose influence on the beam energy is relatively weak, and thus enabling approximate control of the flux ratio supported by National Natural Science Foundation of China (Nos. 11575183, 11175177)

  12. Calibration of the RSS-131 high efficiency ionization chamber for radiation dose monitoring during plasma experiments conducted on plasma focus device

    Science.gov (United States)

    Szewczak, Kamil; Jednoróg, Sławomir

    2014-10-01

    Plasma research poses a radiation hazard. Due to the program of deuterium plasma research using the PF-1000 device, it is an intensive source of neutrons (up to 1011 n · pulse -1) with energy of 2,45 MeV and ionizing electromagnetic radiation with a broad energy spectrum. Both types of radiation are mostly emitted in ultra-short pulses (˜100 ns). The aim of this work was to test and calibrate the RSS-131 radiometer for its application in measurements of ultra-short electromagnetic radiation pulses with broad energy spectrum emitted during PF-1000 discharge. In addition, the results of raw measurements performed in the control room are presented.

  13. Ablation of high-Z material dust grains in edge plasmas of magnetic fusion devices

    Science.gov (United States)

    Marenkov, E. D.; Krasheninnikov, S. I.

    2014-12-01

    The model, including shielding effects of high-Z dust grain ablation in tokamak edge plasma, is presented. In a contrast to shielding models developed for pellets ablation in a hot plasma core, this model deals with the dust grain ablation in relatively cold edge plasma. Using some simplifications, a closed set of equations determining the grain ablation rate Γ is derived and analyzed both analytically and numerically. The scaling law for Γ versus grain radius and ambient plasma parameters is obtained and confirmed by the results of numerical solutions. The results obtained are compared with both dust grain models containing no shielding effects and the pellet ablation models.

  14. Ultralow field emission from thinned, open-ended, and defected carbon nanotubes by using microwave hydrogen plasma processing

    Science.gov (United States)

    Deng, Jian-Hua; Cheng, Lin; Wang, Fan-Jie; Yu, Bin; Li, Guo-Zheng; Li, De-Jun; Cheng, Guo-An

    2015-01-01

    Ultralow field emission is achieved from carbon nanotubes (CNTs) by using microwave hydrogen plasma processing. After the processing, typical capped CNT tips are removed, with thinned, open-ended, and defected CNTs left. Structural analyses indicate that the processed CNTs have more SP3-hybridized defects as compared to the pristine ones. The morphology of CNTs can be readily controlled by adjusting microwave powers, which change the shape of CNTs by means of hydrogen plasma etching. Processed CNTs with optimal morphology are found to have an ultralow turn-on field of 0.566 V/μm and threshold field of 0.896 V/μm, much better than 0.948 and 1.559 V/μm of the as-grown CNTs, respectively. This improved FE performance is ascribed to the structural changes of CNTs after the processing. The thinned and open-ended shape of CNTs can facilitate electron tunneling through barriers and additionally, the increased defects at tube walls can serve as new active emission sites. Furthermore, our plasma processed CNTs exhibit excellent field emission stability at a large emission current density of 10.36 mA/cm2 after being perfectly aged, showing promising prospects in applications as high-performance vacuum electron sources.

  15. Plasma-Material Interface Development for Future Spherical Tokamak-based Devices in NSTX.

    Energy Technology Data Exchange (ETDEWEB)

    et. al, V

    2011-09-24

    , ELMs otherwise suppressed due to lithium conditioning. Fast divertor measurements showed that impulsive particle and heat fluxes due to the ELMs were significantly dissipated in the high magnetic flux expansion region of the snowflake divertor. The snowflake divertor configuration is being combined in experiments with extrinsic deuterium or impurity gas puffing for increased dissipative divertor power losses, additional upper divertor nulls for increased power sharing between the upper and the lower divertors, and lithium coated plasma facing components for large area ion pumping. These efforts are aimed at the development of an integrated PMI for future ST-based devices for fusion development applications.

  16. Device for automatic driving of an mining combine in relation to the open interface of 2 solid media

    Energy Technology Data Exchange (ETDEWEB)

    Zombek, O.I.; Nosulya, Ye.P.; Pavlov, Yu.S.; Shcherbina, V.I.

    1982-01-01

    A device is proposed for automatic driving of a mining combine in relation to the open interface of 2 solid media which include electric hydraulic distributors of lifting and lowering the actuating mechanism, electrodes with mechanism for their compression and hydraulic engine of the caterpillar course. In order to improve accuracy by guaranteeing the possibility of pressing the electrodes to the wall in the shaft with constant force, the mechanism of compression of the electrode is made in the form of 2 hydraulic winches whose piston cavities are interconnected and are connected through the valve of sequence input of the hydraulic motor of the caterpillar course. The interconnected rod cavities of the hydraulic winches are connected to the outlet of the hydraulic motor of the caterpillar course, while the electrodes are installed on the ends of the hydraulic winch rods. The electrical outlets of the electrodes are connected through the contacts of the corresponding relay to the electric hydraulic distributors of lifting and lowering the actuating mechanism. In order to guarantee the necessary accuracy of installing the electrodes on the interface of the 2 solid media, the hydraulic winches are movable over the height in relation to each other. Use of the proposed device in the national economy makes it possible to reduce the loss of minerals which appears because of deviation of the combine into the side rock; to replace the not very effective manual labor of the personnel servicing the mining combine for making shafts in a vertical plane; to increase the content of mineral, sylvinite by reducing the working out of the mineral. In addition to the obtained additional quantity of mineral by increasing the rates of drilling, the proposed device makes it possible to reduce outlays for enrichment.

  17. Seventeen Years’ Experience of Late Open Surgical Conversion after Failed Endovascular Abdominal Aortic Aneurysm Repair with 13 Variant Devices

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ziheng, E-mail: wuziheng303@hotmail.com [Zhejiang University, Department of Vascular Surgery, The First Affiliated Hospital, School of Medicine (China); Xu, Liang, E-mail: maxalive@163.com [Zhejiang University, Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine (China); Qu, Lefeng, E-mail: qulefeng@gmail.com [The Second Military Medical University, Department of Vascular and Endovascular Surgery, Changzheng Hospital (China); Raithel, Dieter, E-mail: dieter.raithel@rzmail.uni-erlangen.de [Nuremberg Southern Hospital, Department of Vascular and Endovascular Surgery (Germany)

    2015-02-15

    PurposeTo investigate the causes and results of late open surgical conversion (LOSC) after failed abdominal aortic aneurysm repair (EVAR) and to summarize our 17 years’ experience with 13 various endografts.MethodsRetrospective data from August 1994 to January 2011 were analyzed at our center. The various devices’ implant time, the types of devices, the rates and causes of LOSC, and the procedures and results of LOSC were analyzed and evaluated.ResultsA total of 1729 endovascular aneurysm repairs were performed in our single center (Nuremberg South Hospital) with 13 various devices within 17 years. The median follow-up period was 51 months (range 9–119 months). Among them, 77 patients with infrarenal abdominal aortic aneurysms received LOSC. The LOSC rate was 4.5 % (77 of 1729). The LOSC rates were significantly different before and after January 2002 (p < 0.001). The reasons of LOSC were mainly large type I endoleaks (n = 51) that were hard to repair by endovascular techniques. For the LOSC procedure, 71 cases were elective and 6 were emergent. The perioperative mortality was 5.2 % (4 of 77): 1 was elective (due to septic shock) and 3 were urgent (due to hemorrhagic shock).ConclusionLarge type I endoleaks were the main reasons for LOSC. The improvement of devices and operators’ experience may decrease the LOSC rate. Urgent LOSC resulted in a high mortality rate, while selective LOSC was relatively safe with significantly lower mortality rate. Early intervention, full preparation, and timely LOSC are important for patients who require LOSC.

  18. Open-wedge high tibial osteotomy: incidence of lateral cortex fractures and influence of fixation device on osteotomy healing.

    Science.gov (United States)

    Dexel, Julian; Fritzsche, Hagen; Beyer, Franziska; Harman, Melinda K; Lützner, Jörg

    2017-03-01

    Open-wedge high tibial osteotomy (HTO) is an established treatment for young and middle-aged patients with medial compartment knee osteoarthritis and varus malalignment. Although not intended, a lateral cortex fracture might occur during this procedure. Different fixation devices are available to repair such fractures. This study was performed to evaluate osteotomy healing after fixation with two different locking plates. Sixty-nine medial open-wedge HTO without bone grafting were followed until osteotomy healing. In patients with an intact lateral hinge, no problems were noted with either locking plate. A fracture of the lateral cortex occurred in 21 patients (30.4 %). In ten patients, the fracture was not recognized during surgery but was visible on the radiographs at the 6-week follow-up. Lateral cortex fracture resulted in non-union with the need for surgical treatment in three out of eight (37.5 %) patients using the newly introduced locking plate (Position HTO Maxi Plate), while this did not occur with a well-established locking plate (TomoFix) (0 out of 13, p = 0.023). With regard to other adverse events, no differences between both implants were observed. In cases of lateral cortex fracture, fixation with a smaller locking plate resulted in a relevant number of non-unions. Therefore, it is recommended that bone grafting, another fixation system, or an additional lateral fixation should be used in cases with lateral cortex fracture. III.

  19. Owgis 2.0: Open Source Java Application that Builds Web GIS Interfaces for Desktop Andmobile Devices

    Science.gov (United States)

    Zavala Romero, O.; Chassignet, E.; Zavala-Hidalgo, J.; Pandav, H.; Velissariou, P.; Meyer-Baese, A.

    2016-12-01

    OWGIS is an open source Java and JavaScript application that builds easily configurable Web GIS sites for desktop and mobile devices. The current version of OWGIS generates mobile interfaces based on HTML5 technology and can be used to create mobile applications. The style of the generated websites can be modified using COMPASS, a well known CSS Authoring Framework. In addition, OWGIS uses several Open Geospatial Consortium standards to request datafrom the most common map servers, such as GeoServer. It is also able to request data from ncWMS servers, allowing the websites to display 4D data from NetCDF files. This application is configured by XML files that define which layers, geographic datasets, are displayed on the Web GIS sites. Among other features, OWGIS allows for animations; streamlines from vector data; virtual globe display; vertical profiles and vertical transects; different color palettes; the ability to download data; and display text in multiple languages. OWGIS users are mainly scientists in the oceanography, meteorology and climate fields.

  20. Development of plasma sources for ICRF heating experiment in KMAX mirror device

    Science.gov (United States)

    Sun, Xuan; Liu, Ming; Yi, Hongshen; Lin, Munan; Shi, Peiyun

    2016-10-01

    KMAX, Keda Mirror with AXisymmeticity, is a tandem mirror machine with a length of 10 meters and diameters of 1.2 meters in the central cell and 0.3 meters in the mirror throat. In the past experiments, the plasma was generated by helicon wave launched from the west end. We obtained the blue core mode in argon discharge, however, it cannot provide sufficient plasma for hydrogen discharge, which is at least 1012 cm-3 required for effective ICRF heating. Several attempts have thus been tried or under design to increase the central cell's plasma density: (1) a washer gun with aperture of 1cm has been successfully tested, and a plasma density of 1013 cm-3 was achieved in the west cell near the gun, however, the plasma is only 1011 cm-3 in the central cell possible due to the mirror trapping and/or neutral quenching effect (2) a larger washer gun with aperture of 2.5 cm and a higher power capacitor bank are being assembled in order to generate more plasmas. In addition, how to mitigate the neutrals is under consideration (3) A hot cathode is been designed and will be tested in combination with plasma gun or alone. Preliminary results from those plasma sources will be presented and discussed.

  1. EDTA-treated cotton-thread microfluidic device used for one-step whole blood plasma separation and assay.

    Science.gov (United States)

    Ulum, Mokhamad Fakhrul; Maylina, Leni; Noviana, Deni; Wicaksono, Dedy Hermawan Bagus

    2016-04-21

    This study aims to observe the wicking and separation characteristics of blood plasma in a cotton thread matrix functioning as a microfluidic thread-based analytical device (μTAD). We investigated several cotton thread treatment methods using ethylenediaminetetraacetic acid (EDTA) anticoagulant solution for wicking whole blood samples and separating its plasma. The blood of healthy Indonesian thin tailed sheep was used in this study to understand the properties of horizontal wicking and separation on the EDTA-treated μTAD. The wicking distance and blood cell separation from its plasma was observed for 120 s and documented using a digital phone camera. The results show that untreated cotton-threads stopped the blood wicking process on the μTAD. On the other hand, the deposition of EDTA anticoagulant followed by its drying on the thread at room temperature for 10 s provides the longest blood wicking with gradual blood plasma separation. Furthermore, the best results in terms of the longest wicking and the clearest on-thread separation boundary between blood cells and its plasma were obtained using the μTAD treated with EDTA deposition followed by 60 min drying at refrigerated temperature (2-8 °C). The separation length of blood plasma in the μTADs treated with dried-EDTA at both room and refrigerated temperatures was not statistically different (P > 0.05). This separation occurs through the synergy of three factors, cotton fiber, EDTA anticoagulant and blood platelets, which induce the formation of a fibrin-filter via a partial coagulation process in the EDTA-treated μTAD. An albumin assay was employed to demonstrate the efficiency of this plasma separation method during a one-step assay on the μTAD. Albumin in blood is an important biomarker for kidney and heart disease. The μTAD has a slightly better limit of detection (LOD) than conventional blood analysis, with an LOD of 114 mg L(-1) compared to 133 mg L(-1), respectively. However, the μTAD performed

  2. XPS, SIMS and FTIR-ATR characterization of boronized graphite from the thermonuclear plasma device RFX-mod

    Energy Technology Data Exchange (ETDEWEB)

    Ghezzi, F., E-mail: ghezzi@ifp.cnr.it [Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, via Cozzi 53, 20125 Milan (Italy); Laguardia, L.; Caniello, R. [Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, via Cozzi 53, 20125 Milan (Italy); Canton, A.; Dal Bello, S.; Rais, B. [Consorzio RFX, Corso Stati Uniti 4, 35127 Padova (Italy); Anderle, M. [Knowledge Department, Provincia Autonoma di Trento, 38123, Trento (Italy)

    2015-11-01

    Highlights: • XPS, ATR and SIMS characterization of samples from the first wall of RFX-mod device. • Amorphous hydrogenated boron carbide plus other carbon type bonds. • Results suggest to increase the number of electrode used for boronization. - Abstract: In this paper the characterization of a thin (tens of nanometers) boron layer on fine grain polycrystalline graphite substrate is presented. The boron film is used as conditioning technique for the full graphite wall of the Reversed Field eXperiment–modified (RFX-mod) experiment, a device for the magnetic confinement of plasmas of thermonuclear interest. Aim of the present analysis is to enlighten the chemical structure of the film, the trapping mechanism that makes it a getter for oxygen and hydrogen and the reason of its loss of effectiveness after exposure to about 100 s of hydrogen plasma. X-ray Photoelectron Spectroscopy (XPS), Secondary Ions Mass Spectrometry (SIMS) and Fourier Transform Infra Red spectroscopy in combination with the Attenuated Total Reflectance (FTIR-ATR) were used to obtain the structure and the chemical composition of graphitic samples as coated or coated and subsequently exposed to hydrogen plasma after boron deposition. The boron layers on the only coated samples were found to be amorphous hydrogenated boron carbide plus a variety of bonds like B-B, B-H, B-O, B-OH, C-C, C-H, C-O, C-OH. Both the thickness and the homogeneity of the layers were found to depend on the distance of the sample from the anode during the deposition. The samples contained oxygen along the layer thickness, at level of 5%, bound to boron. The gettering action of the boron is therefore already active during the deposition itself. The exposure to plasma caused erosion of the boron film and higher content of H and O bound to boron throughout the whole thickness. The interaction of the B layer with plasma is therefore a bulk phenomenon.

  3. An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices

    Science.gov (United States)

    Hartwig, Zachary S.; Barnard, Harold S.; Lanza, Richard C.; Sorbom, Brandon N.; Stahle, Peter W.; Whyte, Dennis G.

    2013-12-01

    This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (˜1 m), high-current (˜1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields - in between plasma shots - to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ˜5 μm into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

  4. On the history of plasma treatment and comparison of microbiostatic efficacy of a historical high-frequency plasma device with two modern devices.

    Science.gov (United States)

    Napp, Judith; Daeschlein, Georg; Napp, Matthias; von Podewils, Sebastian; Gümbel, Denis; Spitzmueller, Romy; Fornaciari, Paolo; Hinz, Peter; Jünger, Michael

    2015-01-01

    Hintergrund: Kaltes Atmosphärendruckplasma (CAP) hat durch seine mannigfaltigen bioaktiven Eigenschaften ein neues medizinisches Feld definiert: die Plasmamedizin. Allerdings wurde vor etwa 100 Jahren CAP in verwandter Form in der Hochfrequenztherapie genutzt. Zielsetzung dieser Studie war eine Übersicht über die historischen Plasmabehandlungen zu gewinnen und Daten bezüglich der antimikrobiellen Wirkung eines historischen Hochfrequenzapparats zu gewinnen.Methode: Erstens wurde historische Literatur bezüglich CAP-Behandlungen ausgewertet, da aus dem heutigen Schrifttum keine Angaben gewonnen werden konnten. Zweitens wurde die Empfindlichkeit von fünf verschiedenen bakteriellen Wundisolaten auf Agar gegenüber einer historischen Plasmaquelle (violet wand [VW]) und zwei modernen Geräten (atmospheric pressure plasma jet [APPJ] und Dielectric Barrier Discharge [DBD]) ermittelt. Die erzielten Hemmhöfe wurde verglichen. Ergebnisse: Die seinerzeit populärsten elektromedizinischen Anwendungen erzeugten durch Glaselektroden sogenannte Effluvien, die mit modernem CAP verwandt sind. Alle drei untersuchten Plasmaquellen zeigten eine vollständige Eradikation aller behandelter Isolate im plasmabehandelten Bereich. Die historische Plasmaquelle (VW) war dabei ähnlich wirksam wie die modernen Plasmaquellen. Schlussfolgerung: In begrenztem Umfang kann retrograd ein Wirksamkeitsnachweis der historischen Plasmabehandlungen abgeleitet werden, insbesondere bei der Behandlung infektiöser Erkrankungen. Die zugrunde liegende Technologie könnte für die Entwicklung moderner Nachfolgegeräte genutzt werden.

  5. Coal-fired open cycle MHD combustion plasmas - Chemical equilibrium and transport properties workshop results

    Science.gov (United States)

    Sullivan, L. D.; Klepeis, J. E.; Coderre, W. J.; Fischer, W. H.

    1980-01-01

    For electrical power generation utilizing a high temperature alkali-seeded coal combustion plasma, the certainty of high electrical conductivity in the presence of coal ash and trace impurities is vitally important, especially for use in extrapolation of existing designs to higher power levels, as envisioned for commercial applications. The paper surveys the results of the workshop which provides an industry wide overview of the computational methods and analyses that are currently in use. Attention is given to uncertainty bands for plasma electrical conductivity. Also discussed are other issues such as coal, slag, seed, and conductivity. Finally, the paper gives suggested areas for further work.

  6. Jet outflow and open field line measurements on the C-2U advanced beam-driven field-reversed configuration plasma experiment

    Science.gov (United States)

    Sheftman, D.; Gupta, D.; Roche, T.; Thompson, M. C.; Giammanco, F.; Conti, F.; Marsili, P.; Moreno, C. D.

    2016-11-01

    Knowledge and control of the axial outflow of plasma particles and energy along open-magnetic-field lines are of crucial importance to the stability and longevity of the advanced beam-driven field-reversed configuration plasma. An overview of the diagnostic methods used to perform measurements on the open field line plasma on C-2U is presented, including passive Doppler impurity spectroscopy, microwave interferometry, and triple Langmuir probe measurements. Results of these measurements provide the jet ion temperature and axial velocity, electron density, and high frequency density fluctuations.

  7. Formation and sustainment of low aspect ratio torus plasma by ECH in the LATE device

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Masaki; Higaki, Kenichi; Yoshinaga, Tomokazu; Igami, Hiroe; Tanaka, Hitoshi; Maekawa, Takashi [Kyoto Univ., Kyoto (Japan)

    2003-07-01

    A plasma current of I{sub p} {approx_equal} 3 kA is generated and maintained for 1 second by injecting a 2.45 GHz microwave power of 5 kW without Ohmic heating power. Magnetic measurements suggest that closed flux surfaces are formed. The electron density inferred from an interferometer is more than 1.0 x 10{sup 11} cm{sup -3} which is beyond the plasma cut off density, suggesting that electron cyclotron heating by mode-converted electron Bernstein waves may be responsible for plasma heating and current drive. The plasma currents are observed to increase with the increase of RF power and equilibrium vertical field, and I{sub p} {approx_equal} 5 kA have been obtained by 2 GHz klystron power of 53 kW. (author)

  8. Ion sensitive probe measurement in the linear plasma device PSI-2

    Energy Technology Data Exchange (ETDEWEB)

    Ezumi, N. [Nagano National College of Technology, 716 Tokuma, Nagano 381-8550 (Japan)]. E-mail: ezumi@ec.nagano-nct.ac.jp; Kiss' ovski, Zh. [Faculty of Physics, Sofia University, Sofia 1164 (Bulgaria); Bohmeyer, W. [Max-Planck-Institut fuer Plasmaphysik, Bereich Plasmadiagnostik, Brook-Taylor-Str. 6, 12489 Berlin (Germany); Fussmann, G. [Max-Planck-Institut fuer Plasmaphysik, Bereich Plasmadiagnostik, Brook-Taylor-Str. 6, 12489 Berlin (Germany)

    2005-03-01

    The suitability of an ion sensitive probe (ISP) with respect to ion temperature (T {sub i}) measurements has been tested in the linear plasma generator in PSI-2. Current-voltage (I-V) characteristics were recorded as a function of two key parameters: shielding height (h) and potential differences between inner and outer electrodes (V {sub B}). It could be experimentally confirmed that the current within the electron saturation region is reduced with increasing h. Furthermore, the I-V characteristics change drastically when V {sub B} is varied. Radial profiles of the plasma parameters including plasma and floating potentials could be taken. Whereas the T {sub i} values determined by ISP in the plasma core region agree fairly with those obtained by using a local optical probe, severe interpretation difficulties occurred for the outer regions.

  9. Effect of oxygen plasma treatment on the electrochemical properties of Prussian blue electrodes for transparent electrochromic devices

    Energy Technology Data Exchange (ETDEWEB)

    Kim, A-Young [Advanced Energy Materials Processing Laboratory, Center for Energy Convergence Research, Green City Research Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Department of Material Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Park, Ji Hun [Advanced Energy Materials Processing Laboratory, Center for Energy Convergence Research, Green City Research Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Byun, Dongjin [Department of Material Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Lee, Joong Kee, E-mail: leejk@kist.re.kr [Advanced Energy Materials Processing Laboratory, Center for Energy Convergence Research, Green City Research Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)

    2013-11-01

    The effect of oxygen plasma on the electrochromic characteristics of electrochromic devices that utilize Prussian blue electrodes is investigated. Prussian blue working electrodes were electrodeposited on fluorine-doped tin oxide films that were grown on glass substrates by electron cyclotron resonance-metal organic chemical vapor deposition. An indium tin oxide coated glass was employed as the counter electrode that served as an ion storage layer. The goal of the oxygen plasma treatment is to increase the oxygen functional groups on the surface of the Prussian blue electrode leading to the enhancement of the oxidation reaction and eventually the increase in coloration efficiency. Improvement of electrochromic properties, such as optical density and response time, was also observed following plasma treatment. - Highlights: • Prussian blue (PB) films on SnOx:F thin film as a working electrode are investigated. • PB color changed that in oxidation state is blue and in reduction state is transparent. • Enhancement of electrochemical performance of electrode after oxygen plasma treatment.

  10. Ammonia formation and W coatings interaction with deuterium/nitrogen plasmas in the linear device GyM

    Science.gov (United States)

    Laguardia, L.; Caniello, R.; Cremona, A.; Dellasega, D.; Dell'Era, F.; Ghezzi, F.; Gittini, G.; Granucci, G.; Mellera, V.; Minelli, D.; Pallotta, F.; Passoni, M.; Ricci, D.; Vassallo, E.

    2015-08-01

    In this work results of the first D2/N2 experiments in GyM, a linear device able to produce plasmas of interest for the ITER divertor (ne 5 ṡ 1010 cm-3, Te 5 eV, ion flux 3-5 ṡ 1020 m-2s-1) are presented. Plasmas simulating a N-seeding scenario have been performed to evaluate ammonia formation and its effect on exposed W coatings. The presence of ND emission lines in the plasma can be correlated with the formation of ammonia, further directly detected and quantified by chromatography analysis of the exhaust. Four different W specimens were exposed in GyM to a plasma fluence of 8.78 ṡ 1023 m-2. XPS analysis evidenced the formation of WxNy layers with nitrogen concentration in the range of 1-10% depending on the initial morphology and structure of the W samples. In all analyzed cases, nitrogen was bound and retained within the first 6 nm below the surface and no further diffusion of N into the bulk was observed.

  11. Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device.

    Science.gov (United States)

    Matsumoto, T; Sekiguchi, J; Asai, T; Gota, H; Garate, E; Allfrey, I; Valentine, T; Morehouse, M; Roche, T; Kinley, J; Aefsky, S; Cordero, M; Waggoner, W; Binderbauer, M; Tajima, T

    2016-05-01

    A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 10(21) m(-3), ∼40 eV, and 0.5-1.0 × 10(19), respectively.

  12. Ammonia formation and W coatings interaction with deuterium/nitrogen plasmas in the linear device GyM

    Energy Technology Data Exchange (ETDEWEB)

    Laguardia, L., E-mail: laguardia@ifp.cnr.it [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Caniello, R.; Cremona, A. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Dellasega, D. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Politecnico di Milano, Dipartimento di Energia, Milan (Italy); Dell’Era, F.; Ghezzi, F.; Gittini, G.; Granucci, G.; Mellera, V.; Minelli, D.; Pallotta, F. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Passoni, M. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Politecnico di Milano, Dipartimento di Energia, Milan (Italy); Ricci, D.; Vassallo, E. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy)

    2015-08-15

    In this work results of the first D{sub 2}/N{sub 2} experiments in GyM, a linear device able to produce plasmas of interest for the ITER divertor (n{sub e} 5 ⋅ 10{sup 10} cm{sup −3}, Te 5 eV, ion flux 3–5 ⋅ 10{sup 20} m{sup −2}s{sup −1}) are presented. Plasmas simulating a N-seeding scenario have been performed to evaluate ammonia formation and its effect on exposed W coatings. The presence of ND emission lines in the plasma can be correlated with the formation of ammonia, further directly detected and quantified by chromatography analysis of the exhaust. Four different W specimens were exposed in GyM to a plasma fluence of 8.78 ⋅ 10{sup 23} m{sup −2}. XPS analysis evidenced the formation of W{sub x}N{sub y} layers with nitrogen concentration in the range of 1–10% depending on the initial morphology and structure of the W samples. In all analyzed cases, nitrogen was bound and retained within the first 6 nm below the surface and no further diffusion of N into the bulk was observed.

  13. The Multiple Resonance Probe: A Novel Device for Industry Compatible Plasma Diagnostics

    Science.gov (United States)

    Brinkmann, Ralf Peter; Storch, Robert; Lapke, Martin; Oberrath, Jens; Schulz, Christian; Styrnoll, Tim; Zietz, Christian; Awakowicz, Peter; Musch, Thomas; Mussenbrock, Thomas; Rolfes, Ilona

    2012-10-01

    To be useful for the supervision or control of technical plasmas, a diagnostic method must be i) robust and stable, ii) insensitive to perturbation by the process, iii) itself not perturbing the process, iv) clearly and easily interpretable without the need for calibration, v) compliant with the requirements of process integration, and, last but not least, vi) economical in terms of investment, footprint, and maintenance. Plasma resonance spectroscopy, exploiting the natural ability of plasmas to resonate on or near the electron plasma frequency, provides a good basis for such an ``industry compatible'' plasma diagnostics. The contribution will describe the general idea of active plasma resonance spectroscopy and introduce a mathematical formalism for its analysis. It will then focus on the novel multipole resonance probe (MRP), where the excited resonances can be classified explicitly and the connection between the probe response and the desired electron density can be cast as a simple formula. The current state of the MRP project will be described, including the experimental characterization of a prototype in comparison with Langmuir probes, and the development of a specialized measurement circuit.

  14. 3D plasma turbulence and neutral simulations using the Hermes model in BOUT + + : a study of linear devices and the tokamak edge and divertor region

    Science.gov (United States)

    Leddy, Jarrod; Dudson, Ben

    2016-10-01

    Understanding the transport processes in the low temperature plasma at the boundary region of magnetic confinement fusion (MCF) devices is crucial to the design and operation of future fusion reactor devices. It influences the divertor heat load, and probably the core confinement as well. The dominant source of this transport is turbulence, which serves to mix the high and low temperature regions of the plasma. The nature of this plasma turbulence is affected by not only the plasma parameters, but also the neutral species that also exist in these low temperature regions. The interaction of neutrals with the plasma turbulence is studied in linear device geometry (for its simplicity, yet similarity in plasma parameters), and the result is a strong interaction that impacts the local plasma and neutral densities, momenta and energies. The neutral gas is found to affect plasma edge turbulence primarily through momentum exchange, reducing the radial electric field and enhancing cross-field transport, with consequent implications for the SOL width and divertor heat loads. Therefore, turbulent plasma and fluid simulations have been performed in multiple tokamak geometries to more closely examine the effects of this interaction. These cases were chosen for the variety in configuration with ISTOK having a toroidal limiter (ie. no divertor), DIII-D having a standard divertor configuration, and MAST-U having a super-X divertor with extended outer divertor legs. Progress towards the characterization of neutral impact on detachment and edge behavior will be presented.

  15. Experimental study of soft X-ray intensity with different anode tips in Amirkabir plasma focus device

    Indian Academy of Sciences (India)

    HABIBI MORTEZA; MAHTAB MAHSA

    2016-07-01

    To study the effect of different anode tip geometries on the intensity of soft X-rays emitted from a 4 kJ plasma focus device (PFD), we considered five different anode tips which were cylindrical-flat, cylindricalhollow, spherical-convex, cone-flat and cone-hollow tips. BPX-65 PIN diodes covered by four different filters are used to register the intensity of soft X-rays. The use of cone-flat anode tip has augmented the emitted X-ray three times compared to the conventional cylindrical-flat anode.

  16. Direct measurement of refracted trajectory of transmitting electron cyclotron beam through plasma on the Large Helical Device

    Directory of Open Access Journals (Sweden)

    Takahashi Hiromi

    2015-01-01

    Full Text Available The electron-cyclotron (EC -beam refraction due to the presence of plasma was investigated in the Large Helical Device. The transmitted-EC-beam measurement system was constructed and the beam pattern on the opposite side of the irradiated surface was measured using an IR camera. Clear dependence of the EC-beam refraction on the electron density was observed and the beam shift in the toroidal direction showed good agreement with the ray-trace calculation of TRAVIS. The influence of the peripheral density profile and the thermal effect on the beam refraction were discussed.

  17. Analysis of cytokine profile and growth factors in platelet-rich plasma obtained by open systems and commercial columns.

    Science.gov (United States)

    Pochini, Alberto de Castro; Antonioli, Eliane; Bucci, Daniella Zanetti; Sardinha, Luiz Roberto; Andreoli, Carlos Vicente; Ferretti, Mario; Ejnisman, Benno; Goldberg, Anna Carla; Cohen, Moisés

    2016-01-01

    To evaluate growth factors and cytokines in samples of platelet-rich plasma obtained by three different centrifugation methods. Peripheral blood of six individuals with no hematological diseases, aged 18 to 68 years, was drawn to obtain platelet-rich plasma, using the open method and commercial columns by Medtronic and Biomet. The products obtained with the different types of centrifugation were submitted to laboratory analysis, including pro-inflammatory cytokines and chemokines by flow cytometry assays, the concentration of fibroblast growth factors-2 (FGF-2) and transforming growth factor-beta1 (TGF-β1). The diverse separation methods generated systematically different profiles regarding number of platelets and leukocytes. The Medtronic system yielded a product with the highest concentration of platelets, and the open method, with the lowest concentration of platelets. The results of cytokine analysis showed that the different types of centrifugation yielded products with high concentrations of interleukin 8, interleukin 1β. The open system resulted in a product with high levels of interleukin 6. Other cytokines and chemokines measured were similar between systems. The product obtained with the open method showed higher levels of TGF-β1 in relation to other systems and low FGF-2 levels. The formed elements, growth factors and cytokines in samples of platelet-rich plasma varied according to the centrifugation technique used. Avaliar fatores de crescimento e citocinas em amostras de plasma rico em plaquetas obtidas por três diferentes métodos de centrifugação. Foi coletado sangue periférico de seis indivíduos, sem doença hematológica, com idades entre 18 e 68 anos, para obtenção de plasma rico em plaquetas, utilizando o método aberto e sistemas comerciais das empresas Medtronic e Biomet. Os produtos obtidos com os diferentes tipos de centrifugação foram submetidos às análises laboratoriais, incluindo citocinas próinflamatórias e quimiocinas

  18. Hybrid Simulation of Supersonic Flow of Weakly Ionized Plasma along Open Field Magnetic Line Effect of Background Pressure

    Science.gov (United States)

    Laosunthara, Ampan; Akatsuka, Hiroshi

    2016-09-01

    In previous study, we experimentally examined physical properties of supersonic flow of weakly ionized expanding arc-jet plasma through an open magnetic field line (Bmax 0.16T). We found supersonic velocity of helium plasma up to Mach 3 and the space potential drop at the end of the magnets. To understand the plasma in numerical point of view, the flows of ion and neutral are treated by particle-based Direct Simulation Monte Carlo (DSMC) method, electron is treated as a fluid. The previous numerical study, we assumed 2 conditions. Ion and electron temperatures were the same (LTE condition). Ion and electron velocities were the same (current-free condition). We found that ion velocity decreased by collision with residual gas molecules (background pressure). We also found that space potential changing with background pressure. In other words, it was indicated that electric field exists and the current-free assumption is not proper. In this study, we add electron continuity and electron momentum equations to obtain electron velocity and space potential. We find that space potential changing with background pressure slightly. It is indicated that electron is essential to space potential formation than ion.

  19. The long way to steady state fusion plasmas - the superconducting stellarator device Wendelstein 7-X

    CERN Document Server

    CERN. Geneva

    2016-01-01

    The stable generation of high temperature Hydrogen plasmas (ion and electron temperature in the range 10-20 keV) is the basis for the use of nuclear fusion to generate heat and thereby electric power. The most promising path is to use strong, toroidal, twisted magnetic fields to confine the electrically charged plasma particles in order to avoid heat losses to the cold, solid wall elements. Two magnetic confinement concepts have been proven to be most suitable: (a) the tokamak and (b) the stellarator. The stellarator creates the magnetic field by external coils only, the tokamak by combining the externally created field with the magnetic field generated by a strong current in the plasma. “Wendelstein 7-X” is the name of a large superconducting stellarator that went successfully into operation after 15 years of construction. With 30 m3 plasma volume, 3 T magnetic field on axis, and 10 MW micro wave heating power, Hydrogen plasmas are generated that allow one to establish a scientific basis for the extrapol...

  20. Aquaregia and Oxygen Plasma Treatments on Fluorinated Tin Oxide for Assembly of PLEDs Devices Using OC1C10-PPV as Emissive Polymer

    Directory of Open Access Journals (Sweden)

    Emerson Roberto SANTOS

    2009-02-01

    Full Text Available In this work were carried out treatments with oxygen plasma and aquaregia on fluorinated tin oxide (FTO films varying the treatment times. After treatments, the samples were analyzed by techniques measurements: sheet resistance, thickness, Hall effect, transmittance and superficial roughness. Devices using FTO/PEDOT:PSS/OC1C10-PPV/Al were assembled. In this experiment some variations were observed by sheet resistance and thickness and Hall effect measurements indicated most elevated carriers concentration and resistivity for aquaregia than that oxygen plasma. The roughness was elevated for the first minutes with treatment by aquaregia too. In the I-V curves the aquaregia devices presented the lowest threshold voltage for 30 minutes and devices treated by oxygen plasma presented a behavior most resistivity different of typical curves for PLEDs devices.

  1. XPS, SIMS and FTIR-ATR characterization of boronized graphite from the thermonuclear plasma device RFX-mod

    Science.gov (United States)

    Ghezzi, F.; Laguardia, L.; Caniello, R.; Canton, A.; Dal Bello, S.; Rais, B.; Anderle, M.

    2015-11-01

    In this paper the characterization of a thin (tens of nanometers) boron layer on fine grain polycrystalline graphite substrate is presented. The boron film is used as conditioning technique for the full graphite wall of the Reversed Field eXperiment-modified (RFX-mod) experiment, a device for the magnetic confinement of plasmas of thermonuclear interest. Aim of the present analysis is to enlighten the chemical structure of the film, the trapping mechanism that makes it a getter for oxygen and hydrogen and the reason of its loss of effectiveness after exposure to about 100 s of hydrogen plasma. X-ray Photoelectron Spectroscopy (XPS), Secondary Ions Mass Spectrometry (SIMS) and Fourier Transform Infra Red spectroscopy in combination with the Attenuated Total Reflectance (FTIR-ATR) were used to obtain the structure and the chemical composition of graphitic samples as coated or coated and subsequently exposed to hydrogen plasma after boron deposition. The boron layers on the only coated samples were found to be amorphous hydrogenated boron carbide plus a variety of bonds like B-B, B-H, B-O, B-OH, C-C, C-H, C-O, C-OH. Both the thickness and the homogeneity of the layers were found to depend on the distance of the sample from the anode during the deposition. The samples contained oxygen along the layer thickness, at level of 5%, bound to boron. The gettering action of the boron is therefore already active during the deposition itself. The exposure to plasma caused erosion of the boron film and higher content of H and O bound to boron throughout the whole thickness. The interaction of the B layer with plasma is therefore a bulk phenomenon.

  2. Excitation and Propagetion of Modified Fluctuation in a Toroidal Plasma in KT-5C Device

    Institute of Scientific and Technical Information of China (English)

    孙玄; 王之江; 陆荣华; 闻一之; 万树德; 俞昌旋; 刘万东; 王成; 潘阁生; 王文浩; 王俊

    2002-01-01

    Understanding the propagation of the turbulent perturbation in the tokamak edge plasma is an important issue to actively modify or control the turbulence, reduce the anomalous transport and improve plasma confmement. To realize active modification of the edge perturbation, a high dynamic output, broad-band, low-cost power amplifier is set up, and used to drive the active probes in the experiments on KT-5C Tokmak. By using small-size magnetic probes together with Langmiur probes, It is observed that the modified perturbation by the active probes with sufficiently driving power may spread with electrostatic mode, and electromagnetic mode as well.

  3. Experimental results on the irradiation of nuclear fusion relevant materials at the dense plasma focus ‘Bora’ device

    Science.gov (United States)

    Cicuttin, A.; Crespo, M. L.; Gribkov, V. A.; Niemela, J.; Tuniz, C.; Zanolli, C.; Chernyshova, M.; Demina, E. V.; Latyshev, S. V.; Pimenov, V. N.; Talab, A. A.

    2015-06-01

    Samples of materials counted as perspective ones for use in the first-wall and construction elements in nuclear fusion reactors (FRs) with magnetic and inertial plasma confinement (W, Ti, Al, low-activated ferritic steel ‘Eurofer’ and some alloys) were irradiated in the dense plasma focus (DPF) device ‘Bora’ having a bank energy of ⩽5 kJ. The device generates hot dense (T ˜ 1 keV, n ˜ 1019 cm-3) deuterium plasma, powerful plasma streams (v ˜ 3 × 107 cm s-1) and fast (E ˜ 0.1 … 1.0 MeV) deuterons of power flux densities q up to 1010 and 1012 W cm-2 correspondingly. ‘Damage factor’ F = q × τ0.5 ensures an opportunity to simulate radiation loads (predictable for both reactors types) by the plasma/ion streams, which have the same nature and namely those parameters as expected in the FR modules. Before and after irradiation we provided investigations of our samples by means of a number of analytical techniques. Among them we used optical and scanning electron microscopy to understand character and parameters of damageability of the surface layers of the samples. Atomic force microscopy was applied to measure roughness of the surface after irradiation. These characteristics are quite important for understanding mechanisms and values of dust production in FR that may relate to tritium retention and emergency situations in FR facilities. We also applied two new techniques. For the surface we elaborated the portable x-ray diffractometer that combines x-ray single photon detection with high spectroscopic and angular resolutions. For bulk damageability investigations we applied an x-ray microCT system where x-rays were produced by a Hamamatsu microfocus source (150 kV, 500 µA, 5 µm minimum focal spot size). The detector was a Hamamatsu CMOS flat panel coupled to a fibre optic plate under the GOS scintillator. The reconstruction of three-dimensional data was run with Cobra 7.4 and DIGIX CT software while VG Studio Max 2.1, and Amira 5.3 were used for

  4. MIP Plasma Decapsulation of Copper-wired Semiconductor Devices for Failure Analysis

    NARCIS (Netherlands)

    Tang, J.

    2014-01-01

    The majority of Integrated Circuit (IC) devices are encapsulated in wire-bonded plastic IC packages. Epoxy molding compound is used as the encapsulation material and gold was used as the bonding wire material. However, the increase of gold material price from 400 USD/ounce in year 2005 to 1400 USD/o

  5. MIP Plasma Decapsulation of Copper-wired Semiconductor Devices for Failure Analysis

    NARCIS (Netherlands)

    Tang, J.

    2014-01-01

    The majority of Integrated Circuit (IC) devices are encapsulated in wire-bonded plastic IC packages. Epoxy molding compound is used as the encapsulation material and gold was used as the bonding wire material. However, the increase of gold material price from 400 USD/ounce in year 2005 to 1400 USD/o

  6. MIP Plasma Decapsulation of Copper-wired Semiconductor Devices for Failure Analysis

    NARCIS (Netherlands)

    Tang, J.

    2014-01-01

    The majority of Integrated Circuit (IC) devices are encapsulated in wire-bonded plastic IC packages. Epoxy molding compound is used as the encapsulation material and gold was used as the bonding wire material. However, the increase of gold material price from 400 USD/ounce in year 2005 to 1400

  7. Portability and Usability of Open Educational Resources on Mobile Devices: A Study in the Context of Brazilian Educational Portals and Android-Based Devices

    Science.gov (United States)

    da Silva, André Constantino; Freire, Fernanda Maria Pereira; Mourão, Vitor Hugo Miranda; da Cruz, Márcio Diógenes de Oliveira; da Rocha, Heloísa Vieira

    2014-01-01

    Open Educational Resources (OER) are freely accessible, openly licensed hypertext, audio, video, simulations, games and animations that are useful for teaching and learning purposes. In order to facilitate the location of such resources, educational content portals are being created, crowding contents that were produced by different teams with…

  8. Proceedings of 1999 U.S./Japan Workshop (99FT-05) On High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    Energy Technology Data Exchange (ETDEWEB)

    NYGREN,RICHARD E.; STAVROS,DIANA T.

    2000-06-01

    The 1999 US-Japan Workshop on High Heat Flux Components and Plasma Surface Interactions in Next Step Fusion Devices was held at the St. Francis Hotel in Santa Fe, New Mexico, on November 1-4, 1999. There were 42 presentations as well as discussion on technical issues and planning for future collaborations. The participants included 22 researchers from Japan and the United States as well as seven researchers from Europe and Russia. There have been important changes in the programs in both the US and Japan in the areas of plasma surface interactions and plasma facing components. The US has moved away from a strong focus on the ITER Project and has introduced new programs on use of liquid surfaces for plasma facing components, and operation of NSTX has begun. In Japan, the Large Helical Device began operation. This is the first large world-class confinement device operating in a magnetic configuration different than a tokamak. In selecting the presentations for this workshop, the organizers sought a balance between research in laboratory facilities or confinement devices related to plasma surface interactions and experimental research in the development of plasma facing components. In discussions about the workshop itself, the participants affirmed their preference for a setting where ''work-in-progress'' could be informally presented and discussed.

  9. Three-dimensional antenna coupling to core plasma in fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Carter, M.D.; Jaeger, E.F.; Stallings, D.C.; Galambos, J.D.; Batchelor, D.B.; Wang, C.Y.

    1995-09-01

    A complete understanding of the RF physics from the launcher to the plasma core is required to fully analyze RF experiments and to evaluate the performance of RF antenna designs in ITER. This understanding requires a consistent model for the RF power launching system, propagation and absorption through the edge region, and the response of the core plasma to the RF power. As a first step toward such a model, the three-dimensional (3D) antenna modeling code, RANT3D, has been coupled with the reduced order full wave code, PICES. Preliminary results from this model are presented in this paper for parameters similar to those found in the DIII-D experiment.

  10. A model for open-close control of cation channels in the plasma membrane of retinal rod outer segments.

    Science.gov (United States)

    Ichikawa, K

    1989-06-01

    A model for open-close control of cation channels in the plasma membrane of retinal rod outer segments is presented. A channel is assumed to open when 3 cGMP molecules bind to it and close as soon as one of the 3 cGMP molecules is released from it. The calcium ion (divalent cation) is a modulator of the channel conductance. The channel conductance is low when Ca2+ binds to it, while it is high when it is free from Ca2+. From the above assumptions, the reaction scheme of channels with cGMP and Ca2+ is created and the fraction of channels in the open and closed states was calculated using equations for this scheme. The kinetic constants used in the model are estimated from the experimental results of many studies and from the theories. From this estimation, it was found that at the physiological concentrations of intracellular and extracellular Ca2+, almost all channels are bound with Ca2+ and are in the low conductance state. The present model accounts for the reported dose(cGMP)-response(membrane current or conductance) relationship, where the Hill coefficient decreases as the cGMP concentration increases. The dark-level cGMP concentration of 8.13 microM is estimated from the model. This is in good agreement with the reported values. Moreover, the model predicts the invariance of current noise at relatively low Ca2+ concentrations when the cGMP concentration is raised from the dark level to a saturation level. The dynamic properties (opening and closing actions) of the channels in the present model are also in good agreement with the reported observations. The burst mode opening and closing of a channel is predicted by the present model, and it was found that the number of openings in a burst is controlled by the forward and backward rate constants between a channel protein and cGMP molecules. The simulated waveform of a single channel is similar to the reported observations.

  11. Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device

    Energy Technology Data Exchange (ETDEWEB)

    Peng, S.Y.

    1991-07-01

    Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of the thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple eigenmode computational analysis of the fields that exist within the plasma-vacuum system. The inhomogeneous axial field is treated by dividing the geometry into a series of transverse axial slices and using a constant dielectric tensor in each individual slice. The slices are then connected by longitudinal boundary conditions.

  12. Atmospheric pressure plasma jet-synthesized electrochromic organomolybdenum oxide thin films for flexible electrochromic devices

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yung-Sen, E-mail: yslin@fcu.edu.tw; Tsai, Tsung-Hsien; Tien, Shih-Wei

    2013-02-01

    An investigation is conducted into fast synthesis of electrochromic organomolybdenum oxide (MoO{sub x}C{sub y}) thin films onto 40 Ω/□ flexible polyethylene terephthalate/indium tin oxide substrates via atmospheric pressure plasma jet. A precursor [molybdenum carbonyl, Mo(CO){sub 6}] vapor, carried by argon gas, is injected into air plasma torch to synthesize MoO{sub x}C{sub y} films for offering extraordinary electrochromic performance. Only low driving voltages from − 1 V to 1 V are needed to offer reversible Li{sup +} ion intercalation and deintercalation in a 1 M LiClO{sub 4}-propylene carbonate electrolyte. Light modulation with transmittance variation of up to 61%, optical density change of 0.54 and coloration efficiency of 37.5 cm{sup 2}/C at a wavelength of 550 nm after 200 cycles of cyclic voltammetry switching measurements is achieved. - Highlights: ► Fast deposition of MoO{sub x}C{sub y} film by an atmospheric pressure plasma jet ► Organic–inorganic hybrid MoO{sub x}C{sub y} films synthesized ► Flexible and electrochromic MoO{sub x}C{sub y} films produced.

  13. Influences on ionization fraction in an inductively coupled ionized physical vapor deposition device plasma

    Science.gov (United States)

    Juliano, Daniel R.; Ruzic, David N.; Allain, Monica M. C.; Hayden, Douglas B.

    2002-01-01

    A computer simulation was created to model the transport of sputtered atoms through an ionized physical vapor deposition (IPVD) system. The simulation combines Monte Carlo and fluid methods to track the metal atoms that are emitted from the target, interact with the IPVD plasma, and are eventually deposited somewhere in the system. Ground-state neutral, excited, and ionized metal atoms are tracked. The simulation requires plasma conditions to be specified by the user. Langmuir probe measurements were used to determine these parameters in an experimental system in order to compare simulation results with experiment. The primary product of the simulation is a prediction of the ionization fraction of the sputtered atom flux at the substrate under various conditions. This quantity was experimentally measured and the results compared to the simulation. Experiment and simulation differ significantly. It is hypothesized that heating of the background gas due to the intense sputtered atom flux at the target is primarily responsible for this difference. Heating of the background gas is not accounted for in the simulation. Difficulties in accurately measuring plasma parameters, especially electron temperature, are also significant.

  14. Comparison of measured and computed radial trajectories of plasma focus devices UMDPF1 and UMDPF0

    Energy Technology Data Exchange (ETDEWEB)

    Lim, L. H.; Yap, S. L., E-mail: yapsl@um.edu.my; Lim, L. K.; Lee, M. C.; Poh, H. S.; Ma, J. [Plasma Technology Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Yap, S. S. [UMPEDAC, University of Malaya, 50603 Kuala Lumpur (Malaysia); Faculty of Engineering, Multimedia University, Cyberjaya, 63100 Selangor (Malaysia); Lee, S. [Plasma Technology Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 (Australia)

    2015-09-15

    In published literature, there has been scant data on radial trajectory of the plasma focus and no comparison of computed with measured radial trajectory. This paper provides the first such comparative study. We compute the trajectories of the inward-moving radial shock and magnetic piston of UMDPF1 plasma focus and compare these with measured data taken from a streak photograph. The comparison shows agreement with the measured radial trajectory in terms of average speeds and general shape of trajectory. This paper also presents the measured trajectory of the radially compressing piston in another machine, the UMDPF0 plasma focus, confirming that the computed radial trajectory also shows similar general agreement. Features of divergence between the computed and measured trajectories, towards the end of the radial compression, are discussed. From the measured radial trajectories, an inference is made that the neutron yield mechanism could not be thermonuclear. A second inference is made regarding the speeds of axial post-pinch shocks, which are recently considered as a useful tool for damage testing of fusion-related wall materials.

  15. Simulation of open-loop plasma vertical movement response in the Damavand tokamak using closed-loop subspace system identification

    Science.gov (United States)

    Darestani Farahani, N.; Abbasi Davani, F.

    2016-02-01

    The formulation of a multi-input single-output closed-loop subspace method for system identification has been employed for the purpose of obtaining control-relevant model of the open loop response for plasma vertical movement in the Damavand tokamak. Such a model is particularly well suited for the robust controller design. The method described in this paper is a kind of worst-case identification technique, aiming to minimize the error between the identified model and the true plant. The accuracy of the estimation of the plant dynamics has been tested by different experiments. The fitness of the identified model around the defined operating point has been more than 90%, and compared to the physical-based model, it has better root mean squared error (RMSE) measure of the goodness of fitting.

  16. TH-C-BRB-02: Open Source Medical Devices: Lessons Learned From a Complex Collaborative Research Project.

    Science.gov (United States)

    Prajapati, S

    2016-06-01

    By definition, Open Source Hardware (OSH) is "hardware whose design is made publicly available so that anyone can study, modify, distribute, make, and sell the design or hardware based on that design". The advantages of OSH are multiple and the movement has been growing exponentially over the last couple years, leading to the spread and evolution of 3D printing technologies, the creation of affordable and easy to use micro-controller boards (Arduino, Raspberry Pi, etc.), as well as a plurality of other "hands-on"/DIY projects. As we have seen over the past few years with 3D printing, where the number of projects benefiting clinical practice as grown significantly, the highly educated and technology savvy Medical Physics community is positioned to take advantage of and benefit from paradigm-shifting movements. Sharing of knowledge, know-how, and technology can be a key factor in furthering the impact medical physicists can have. Whether it is to develop phantoms, applicators, detector holders or devices based on the use of motors and sensors, sharing design files significantly enables further development. Because these designs would be massively peer-reviewed through their online publication, improvements would be made, and the creators of the design would be rewarded with an increase number of citation of their work. A curated database of software and hardware projects can be an invaluable to the field, but a critical mass of contributors is likely needed to guarantee the most impact. This symposium will discuss the benefits and hurdles for such an endeavor.

  17. Plasma Microdischarge as Power-Induced Limiter Element in Microstrip Devices

    OpenAIRE

    Pascaud, Romain; Pizarro, Francisco; Callegari, Thierry; Liard, Laurent; Pascal, Olivier

    2015-01-01

    The use of micro-hollow cathode sustained discharges (MCSD) as power-induced limiter elements in microstrip devices is proposed to protect receivers against high-power microwave (HPM) threats. The basic principle of the MCSD and its integration into a microstrip circuit are exposed. The power-limiting capability of such a solution has been experimentally assessed for three microstrip circuits, namely a microstrip transmission line, a microstrip ring filter, and a microstrip antenna.

  18. Inorganic-solid-state electrolyte layer deposited by cathodic arc plasma for rapidly switching electrochromic device

    Science.gov (United States)

    Chen, Po-Wen; Chang, Chen-Te; Wu, Jin-Yu; Jan, Der-Jun; Li, Yu-Chen; Hsieh, Cheng-Chang; Tsai, Wen-Fa

    2017-08-01

    This work focuses on fabricating a solid electrolyte Ta2O5 thin film deposited by cathodic arc plasm (CAP) deposition through three different ratio of oxygen and argon. In our experiments, refractive index of Ta2O5 films are taken as 2.25, 1.96, 1.9 with various O2/Ar= 1.5, O2/Ar= 2, O2/Ar= 2.4, respectively. Our results show that the refractive index mostly decreased as we increase the oxygen flow rate, in which the minimum is found at 240 sccm. It provides good conduction pathways for ions through smaller thin-film's refractive index that exhibits more porosity voids. This property enhances ion's mobility for electrochromic device causing rapid coloring/bleaching phenomenon. Ta2O5 thin film is suitable as a solid electrolyte layer in center of electrochromic device (ECD) using CAP deposition. As a result, rapid response times were observed in fabricated device with an area of 5 cm×5 cm, exhibiting transmittance optical modulation ΔT = 61.5% (@550 nm) with the bleaching time τ = 8 s and transmittance optical modulation ΔT = 50% (@550 nm) with the coloring time τ = 10 s.

  19. Simulation of Low-Voltage Arc Plasma During Contact Opening Progress

    Institute of Scientific and Technical Information of China (English)

    WU Yi; RONG Ming-zhe; SUN Zhi-qiang; WANG Xiao-hua; LI Jian; WANG Jian-hua

    2007-01-01

    This paper focuses on the simulation of the low-voltage arc with an opening contact.A controllable experiment setup with a rotating contact is designed to investigate the arc behaviour.Supported by the experiment,the phenomena of arc elongation and commutation in the case of rotating contact are simulated with the dynamic grid technique introduced.Under the given condition of the external magnetic field and the contact rotating velocity,the stagnation and rapid jump of two arc roots are observed by the calculated and experimental arc root displacement.The voltage of arc column can be divided into four phases and its sharp rising progress comes from the increase of the displacement difference between two arc roots in x direction.

  20. Electron ionization of open/closed chain isocarbonic molecules relevant in plasma processing: Theoretical cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Umang R., E-mail: umangpatel193@yahoo.ca [Gandhinagar Institute of Technology, Moti Bhoyan, Gandhinagar-382721, Gujarat (India); Sardar Patel University, Vallabh Vidyanagar-388120, Gujarat (India); Joshipura, K. N.; Pandya, Siddharth H. [Sardar Patel University, Vallabh Vidyanagar-388120, Gujarat (India); Kothari, Harshit N. [Universal College of Engineering and Technology, Moti Bhoyan, Gandhinagar-382721, Gujarat (India)

    2014-01-28

    In this paper, we report theoretical electron impact ionization cross sections from threshold to 2000 eV for isocarbonic open chain molecules C{sub 4}H{sub 6}, C{sub 4}H{sub 8}, C{sub 4}F{sub 6} including their isomers, and closed chain molecules c-C{sub 4}H{sub 8} and c-C{sub 4}F{sub 8}. Theoretical formalism employed presently, viz., Complex Scattering Potential-ionization contribution method has been used successfully for a variety of polyatomic molecules. The present ionization calculations are very important since results available for the studied targets are either scarce or none. Our work affords comparison of C{sub 4} containing hydrocarbon versus fluorocarbon molecules. Comparisons of the present ionization cross sections are made wherever possible, and new ionization data are also presented.

  1. Five-year extension of a clinical trial comparing the EX-PRESS glaucoma filtration device and trabeculectomy in primary open-angle glaucoma.

    Science.gov (United States)

    de Jong, Leo; Lafuma, Antoine; Aguadé, Anne-Sophie; Berdeaux, Gilles

    2011-01-01

    This study compared the efficacy of the EX-PRESS(®) glaucoma filtration device and trabeculectomy in primary open-angle glaucoma up to five years after surgery. Patients from a previously reported randomized, open-label, parallel-arm clinical trial in which 78 patients received either the EX-PRESS glaucoma filtration device or underwent a trabeculectomy were followed for up to an additional four years (five total) beyond the original study (39 eyes per treatment group). Risk-benefit data were obtained for up to five years after glaucoma surgery. Outcome variables were intraocular pressures and intraocular pressure medications. Complete success was denoted by intraocular pressure values ≤ 18 mmHg without medication. The EX-PRESS glaucoma filtration device controlled intraocular pressure more effectively without medication for more patients from year 1 (86.8% versus 61.5%, P = 0.01) to year 3 (66.7% versus 41.0%, P = 0.02) than trabeculectomy. At year 1, only 12.8% of patients required intraocular pressure medication after EX-PRESS implantation, compared with 35.9% after trabeculectomy. The proportions became closer at year 5 (41% versus 53.9%). The responder rate was higher with EX-PRESS and time to failure was longer. In addition, surgical interventions for complications were fewer after EX-PRESS implantation. This five-year analysis confirmed and extended the results reported after one year. Compared with trabeculectomy, EX-PRESS provided better intraocular pressure control in the first three years, and patients required fewer intraocular pressure medications and fewer surgical interventions during the five-year study period. For patients with primary open-angle glaucoma, the EX-PRESS glaucoma filtration device, implanted under a superficial scleral flap, produced significantly higher success rates than trabeculectomy. EX-PRESS is an effective device for long-term treatment of primary open-angle glaucoma.

  2. Resonant magnetic perturbations of edge-plasmas in toroidal confinement devices

    Science.gov (United States)

    Evans, T. E.

    2015-12-01

    Controlling the boundary layer in fusion-grade, high-performance, plasma discharges is essential for the successful development of toroidal magnetic confinement power generating systems. A promising approach for controlling the boundary plasma is based on the use of small, externally applied, edge resonant magnetic perturbation (RMP) fields (δ b\\bot\\text{ext}≈ {{10}-4}\\to {{10}-3}~\\text{T} ). A long-term focus area in tokamak fusion research has been to find methods, involving the use of non-axisymmetric magnetic perturbations to reduce the intense particle and heat fluxes to the wall. Experimental RMP research has progressed from the early pioneering work on tokamaks with material limiters in the 1970s, to present day research in separatrix-limited tokamaks operated in high-confinement mode, which is primarily aimed at the mitigation of the intermittent fluxes due edge localized modes (ELMs). At the same time, theoretical research has evolved from analytical models to numerical simulations, including the full 3D complexities of the problem. Following the first demonstration of ELM suppression in the DIII-D tokamak during 2003, there has been a rapid worldwide growth in theoretical, numerical and experimental edge RMP research resulting in the addition of ELM control coils to the ITER baseline design (Loarte et al 2014 Nucl. Fusion 54 033007). This review provides an overview of edge RMP research including a summary of the early theoretical and numerical background along with recent experimental results on improved particle and energy confinement in tokamaks triggered by edge RMP fields. The topics covered make up the basic elements needed for developing a better understanding of 3D magnetic perturbation physics, which is required in order to utilize the full potential of edge RMP fields in fusion relevant high performance, H-mode, plasmas.

  3. Spectral survey of helium lines in a linear plasma device for use in HELIOS imaging

    Science.gov (United States)

    Ray, H. B.; Biewer, T. M.; Fehling, D. T.; Isler, R. C.; Unterberg, E. A.

    2016-11-01

    Fast visible cameras and a filterscope are used to examine the visible light emission from Oak Ridge National Laboratory's Proto-MPEX. The filterscope has been configured to perform helium line ratio measurements using emission lines at 667.9, 728.1, and 706.5 nm. The measured lines should be mathematically inverted and the ratios compared to a collisional radiative model (CRM) to determine Te and ne. Increasing the number of measurement chords through the plasma improves the inversion calculation and subsequent Te and ne localization. For the filterscope, one spatial chord measurement requires three photomultiplier tubes (PMTs) connected to pellicle beam splitters. Multiple, fast visible cameras with narrowband filters are an alternate technique for performing these measurements with superior spatial resolution. Each camera contains millions of pixels; each pixel is analogous to one filterscope PMT. The data can then be inverted and the ratios compared to the CRM to determine 2-dimensional "images" of Te and ne in the plasma. An assessment is made in this paper of the candidate He I emission lines for an imaging technique.

  4. Radiography using a dense plasma focus device as a source of pulsed X-rays

    Science.gov (United States)

    Herrera, Julio; Castillo, Fermín; Gamboa, Isabel; Rangel, José

    2007-11-01

    Soft and hard X-ray emissions have been studied in the FN-II, which is a small dense plasma focus machine (5 kJ), operating at the Instituto de Ciencias Nucleares, UNAM, using aluminum filtered pin-hole cameras. Their angular distribution has been measured using TLD-200 dosimeters [1]. Their temporal evolution has been observed by means of a PIN diode, and scinltillators coupled to photomultipliers outside the discharge chamber. The X rays source can be concentrated by placing a needle on the end of the electrode. X-rays crossing across a 300 micron aluminum window, through the axis of the machine, can be used to obtain high contrast radiographs, with an average dose of 0.4 mGy per shot. In contrast, the average dose with a hollow cathode is 0.2 mGy per shot. This work is partially supported by grant IN105705 de la DGAPA-UNAM. [1] F. Castillo, J.J.E. Herrera, J. Rangel, I. Gamboa, G. Espinosa y J.I. Golzarri ``Angular Distribution of fusion products and X-rays emitted by a small dense plasma focus machine'' Journal of Applied Physics 101 013303-1-7 (2007).

  5. Plasma processing of niobium for the production of thin-film superconducting devices

    Energy Technology Data Exchange (ETDEWEB)

    Tugwell, A.J.; Hutson, D.; Pegrum, C.M.; Donaldson, G.B.

    1987-01-01

    Josephson junctions, which are regions of weak electrical connection between two superconductors, are the active elements of very sensitive thin-film magnetometers. Junctions are fabricated by growing barriers of native oxide on thin Nb films and depositing a layer of PbIn alloy on top. High sensitivity magnetometers require junctions of small area, and to achieve this, edge junctions are fabricated in which one dimension is defined by the thickness of the Nb and the other is set by the limit of optical lithography. An edge with a suitable angle is produced by reactive ion etching using 5 vol % O/sub 2/ in CF/sub 4/ in a parallel plate rf plasma etcher. Details of etch rates and edge profiles are given. The barrier is formed by a cleaning and oxidation process in an rf plasma at a pressure of 10/sup -6/ bar. Details of the design of a purpose built rf cathode and the run-to-run reproducibility of junction characteristics are given. Different oxidation times and bias voltages are necessary to produce a given oxide thickness on a sloping edge of Nb, as compared to a planar surface, and an explanation for this is proposed. Examples are described of magnetometers made using the above processes.

  6. Independent control of ion current and ion impact energy onto electrodes in dual frequency plasma devices

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, P C; Ellingboe, A R; Turner, M M [Plasma Research Laboratory, National Centre for Plasma Science and Technology and School of Physical Sciences, Dublin City University, Dublin 9 (Ireland)

    2004-03-07

    Dual frequency capacitive discharges are designed to offer independent control of the flux and energy of ions impacting on an object immersed in a plasma. This is desirable in applications such as the processing of silicon wafers for microelectronics manufacturing. In such discharges, a low frequency component couples predominantly to the ions, while a high frequency component couples predominantly to electrons. Thus, the low frequency component controls the ion energy, while the high frequency component controls the plasma density. Clearly, this desired behaviour is not achieved for arbitrary configurations of the discharge, and in general one expects some unwanted coupling of ion flux and energy. In this paper we use computer simulations with the particle-in-cell method to show that the most important governing parameter is the ratio of the driving frequencies. If the ratio of the high and low frequencies is great enough, essentially independent control of the ion energy and flux is possible by manipulation of the high and low frequency power sources. Other operating parameters, such as pressure, discharge geometry, and absolute power, are of much less significance.

  7. 6-7 Mev Characteristic Gamma-Ray Source Using A Plasma Opening Switch And A Marx Bank

    Science.gov (United States)

    2011-06-01

    of Hawk, including the POS, is shown in Fig. 2a. The POS consists of 12 plasma guns made from coaxial cables that inject ionized plasma radially...inward between two coaxial conductors prior to firing the generator. The POS plasma conducts the generator current as a short circuit for about 700...vacuum gap in the plasma . High-energy electron- and ion-beams form in the plasma -filled coaxial region, with ions from the plasma and the polyethylene

  8. Comparisons of Computational Methods to Represent Electron Transport in Nonequilibrium Plasma Devices.

    Science.gov (United States)

    Pak, Hoyoung

    Low pressure optically triggered pseudosparks, or Back-Lit Thyratrons (BLT), are inherently multidimensional transient devices. The method employed to model electron transport in such devices is therefore problematic. A versatile model for these switches with which to compare different modeling approaches has been developed. In the two-dimensional, time dependent model, fluid equations are solved to obtain the electron and ion densities, and Poisson's equation is solved for the electric potential. These equations can be solved using the local field approximation (LFA), employing conservation equations for the bulk electron energy and momentum, or adding multiple beam components to the electron energy distribution. Combinations of these methods can also be employed. The model has been exercised to determine the parameter space, e.g., gas pressure, voltage, electrode gaps, in which each of these methods can be reliably used. Due to the induction time required to achieve quasi -equilibrium conditions, employing the energy equation and beam components typically slows the response of the switch compared to using the LFA. A separate model has also been developed to study breakdown in BLTs. In parallel plane geometries, the Paschen curve can be used to predict breakdown voltages as a function of pcdot d (gas pressure times electrode separation). When electrodes are not planar, i.e., central holes in electrodes, the breakdown deviates from that given by the Paschen curve. The details of the breakdown conditions for hollow electrode geometries have been investigated, and scaling laws derived.

  9. Collaborative Research: Fundamental Studies of Plasma Control Using Surface Embedded Electronic Devices

    Energy Technology Data Exchange (ETDEWEB)

    Overzet, Lawrence J. [Univ. of Texas, Dallas, TX (United States); Raja, L. [Univ. of Texas, Austin, TX (United States)

    2015-06-06

    The research program was collaborative between the researchers at the University of Texas at Dallas and the University of Texas at Austin. The primary subject of this program was to investigate the possibility of active control of secondary electron emission (SEE) from surfaces in contact with plasmas and thereby actively control plasmas. Very few studies of ion-induced electron emission (IIEE) from semiconductors exist, and those that do exist primarily used high-energy ion beams in the experiments. Furthermore, those few studies took extreme measures to ensure that the measurements were performed on atomically clean surfaces because of the surface sensitivity of the IIEE process. Even a small exposure to air can change the IIEE yield significantly. In addition, much of the existing data for IIEE from semiconductors was obtained in the 1950s and ‘60s, when semiconductor materials were first being refined. As a result, nearly all of that data is for p-type Ge and Si. Before this investigation, experimental data on n-type materials was virtually non-existent. While the basic theory assumed that IIEE yields ought to be substantially independent of doping type and concentration, recent measurements of near atmospheric pressure plasmas and of breakdown suggested otherwise. These indirect measurements were made on surfaces that were not atomically clean and seemed to indicate that deep sub-surface changes to the bulk conduction band electron density could lead to substantial variations in the IIEE yield. Exactly in contradiction to the generally accepted theory. Insufficient direct data existed to settle the matter. We performed both experimental measurements and theoretical calculations of IIEE yields from both Si and Ge in order to help clarify whether or not conduction band electrons substantially change the IIEE yield. We used three wafers of each material to carry out the investigation: a heavily doped p-type, an intrinsic and a heavily doped n-type wafer. There

  10. The effect of anode shape on neon soft x-ray emissions and current sheath configuration in plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, M A; Sobhanian, S [Faculty of Physics, University of Tabriz, Tabriz (Iran, Islamic Republic of); Wong, C S [Plasma Research Laboratory, Physics Department, University of Malaya, Kuala Lumpur (Malaysia); Lee, S; Lee, P; Rawat, R S, E-mail: rajdeep.rawat@nie.edu.s [Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University (Singapore)

    2009-02-21

    The effect of three different anode shapes, flat, tapered and hemispherical, on the x-ray emission characteristics of a neon filled UNU-ICTP plasma focus device is investigated. The current sheath dynamics, in the radial collapse phase, has been simultaneously interrogated using the laser shadowgraphy method to understand the variation in x-ray emission characteristics for anodes of different shapes used in the experiments. The maximum neon soft x-ray (SXR) yield for the flat anode is about 7.5 {+-} 0.4 J at 4 mbar, whereas for hemispherical and tapered anodes the neon SXR is almost halved with the optimum pressure shifting to a lower value of 3 mbar. The laser shadowgraphic images confirm that the reduction in the overall neon SXR yield is due to the reduced focused plasma column length for these anodes. The relative HXR yield was the highest for the hemispherical anode followed by the tapered and the flat anodes in that order. The shadowgraphic images and the voltage probe signals confirmed that for the hemispherical anode the multiple-pinch phenomenon was most commonly observed, which could be responsible for multiple HXR bursts for this anode with maximum HXR yields.

  11. Progress of divertor simulation research toward the realization of detached plasma using a large tandem mirror device

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, Y., E-mail: nakashma@prc.tsukuba.ac.jp [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Takeda, H.; Ichimura, K.; Hosoi, K.; Oki, K.; Sakamoto, M.; Hirata, M.; Ichimura, M.; Ikezoe, R.; Imai, T.; Iwamoto, M.; Hosoda, Y.; Katanuma, I.; Kariya, T.; Kigure, S.; Kohagura, J.; Minami, R.; Numakura, T.; Takahashi, S.; Yoshikawa, M. [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); and others

    2015-08-15

    This paper describes the results of the experiments performed on Tandem Mirror device GAMMA 10/PDX mainly using a new “divertor simulation experimental module (D-module)” installed on one of the end mirror exits which is specially designed to investigate the physics of plasma detachment. The additional ICRF heating in the anchor-cells, connected to both ends of the central-cell, significantly increases the density in the both cells, which attained the generation of the highest particle flux up to 10{sup 23} particles/s m{sup 2} at the end-mirror exit. H{sub 2} and noble gas injection to enhance the radiation cooling in D-module was performed and a remarkable reduction of the electron temperature (from few tens eV to <3 eV) on the target plate were successfully achieved associated with the strong reduction of particle and heat flux. A significant effect of simultaneous injection with hydrogen and noble gases for detached plasma formation was recognized for the first time.

  12. Studies of inductive plasmas and their application to theta-pinch devices via numerical modeling

    Science.gov (United States)

    Meeks, Warner Charles

    First, a globally-averaged RF plasma model is used to investigate exit conditions immediately following a RF pre-ionization stage. Analysis shows that reducing pulse duration from 10-6 to 10-7 seconds increases peak ion energy fraction by 17% (from 16 to 33%) and doubles final conductivity. Pulse waveforms are square in nature, and ion energy fraction is defined in this work as the percentage of total input energy entrained in ions. Increasing total energy deposition from 5 to 160 mJ increases ion energy fraction from 33% to 58% at a 200 ns pulse duration. This increase is not linear however, showing instead a diminishing return with a peak fraction plateau estimated at 65% to 70%. A constant (time-average) power analysis reveals that, across all power levels (10 to 100 kW), energies (5 mJ to 1 joule), and durations (0.05 to 10 µs), peak ion energy fraction consistently occurs approximately 1 to 2 µs before peak conductivity. Second, single particle and particle-in-cell simulations are used to elucidate breakdown physics in a ringing theta-pinch with bias magnetic field. The analyses presented here agree with previously conducted experimental results showing that gas breakdown occurs only upon approximate nullification of the bias magnetic field by the pulsed theta-pinch magnetic field. Parametric analysis of the peak electron energy as a function of the bias and pre-ionization magnetic fields reveals that; 1.) when bias magnetic field is ≈ 97% of the pre-ionization magnetic field the peak electron energy is highly erratic, and 2.) high electron energy levels require a pre-ionization to bias magnetic field ratio of 2 to 1 or higher. This second work went on to be published in the Phys. of Plasmas Journal, Vol. 19 (2012, http://link.aip.org/link/doi/10.1063/1.4717731).

  13. Compression between ion and hard x-ray emissions from nitrogen and argon in Mather type plasma focus device

    Directory of Open Access Journals (Sweden)

    S Paghe

    2016-12-01

    Full Text Available In this study, some characteristics of a Mather type Plasma Focus (PF device such as a discharge current, pinch time, ion flux and hard x-ray intensity has been investigated simultaneously in argon and nitrogen gases separately for various operating gas pressures and charging voltages of capacitor bank. It was observed that pinch phenomena was energy and pressure dependent in current sheath as well as ion and hard x-ray emission intensity. Optimum pressure with maximum ion flux and the most intense hard x-ray showed a nearly linear dependence on the charging voltage of the device. Maximum ion flux was estimated in the order of 1018 ions per steradian in both gases. Hard x-ray emission was registered a little after discharge current and Faraday cup (FC signals. Also, optimum pressure for maximum ion flux was not the same as the pressure for intense hard x-rays. Hard x-ray intensity reached its peak at higher pressures

  14. Achieving Better Buying Power Through Acquisition of Open Architecture Software Systems for Web-Based and Mobile Devices

    Science.gov (United States)

    2015-04-30

    reciprocity for shared development, (9) collaborative buying, (10) donation, (11) sponsored development, (12) free / open source software (e.g., Government OSS...review and approve choices between functionally similar open source software (OSS) components, and commercially priced closed source software (CSS...OWF) is a government open source software (GOSS) effort that is central to such agile OA system development. The OZONE family of products includes

  15. ELM-induced melting: assessment of shallow melt layer damage and the power handling capability of tungsten in a linear plasma device

    Science.gov (United States)

    Morgan, T. W.; van Eden, G. G.; de Kruif, T. M.; van den Berg, M. A.; Matejicek, J.; Chraska, T.; De Temmerman, G.

    2014-04-01

    Tungsten samples were exposed to combined steady state and edge localised mode transient replication experiments in a linear plasma device; either in combined hydrogen plasma and high powered laser exposures at Magnum-PSI or steady state hydrogen plasma and superimposed plasma pulses created using a capacitor bank in Pilot-PSI. With each transient the surface temperature of the sample was elevated above the melting point creating a shallow molten layer. An apparent heat transport reduction in the near surface layer increases as a function of pulse number. Scanning electron microscopy analysis of the samples shows large scale grain enlargement down to several hundred to thousand micrometers below the surface as well as melt layer motion due to evaporative recoil from the molten surface. In the ITER divertor this would lead to severe embrittlement and enhanced erosion of the tungsten surface leading to reduced lifetimes for the plasma facing material.

  16. US-Japan workshop Q-181 on high heat flux components and plasma-surface interactions for next devices: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, R.T. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Yamashina, T. [ed.] [Hokkadio Univ. (Japan)

    1994-04-01

    This report contain viewgraphs of papers from the following sessions: plasma facing components issues for future machines; recent PMI results from several tokamaks; high heat flux technology; plasma facing components design and applications; plasma facing component materials and irradiation damage; boundary layer plasma; plasma disruptions; conditioning and tritium; and erosion/redeposition.

  17. Experimental studies of a microsecond plasma opening switch in the positive polarity regime with inductive load/extraction ion diode

    Science.gov (United States)

    Bystritskii, V. M.; Lisitsyn, I. V.; Sinebryukhov, V. A.; Volkov, S. N.; Krasik, Ya. E.

    1992-06-01

    Systematic studies of the microsecond plasma opening switch (MPOS) operation in the positive polarity of its inner electrode with an inductive load/B-applied ion diode of the extraction type at a level of 0.3 TW of dissipated power were performed at the DOUBLE generator (300 kA, 480 kV, 1 μs). The detailed measurements of ion flow parameters in the conductive phase of the MPOS showed the considerable enhancement of the ion current amplitude over the thermal flow limit (3-10 times) which is coupled with a significant decrease of electron conductivity in the MPOS across its self-magnetic field. The positive polarity MPOS operation proved to be more critical to the stored current amplitudes and geometry of the electrodes in comparison with the negative polarity case. This fact resulted in limitations of satisfactory performance of the MPOS involving short high-voltage pulse duration, low stored current amplitudes, and a narrow region of acceptable electrode diameters. The variation of the diode anode-cathode (AC) gap provided a sensitive control of the MPOS + magnetically insulated diode (MID) system, which displayed very strong coupling, resulting in clamping of the output voltage in a wide region of diode impedances. The early long-duration (<300 ns) high-voltage (50-200 kV) prepulse improves plasma production at the anode of the MID prior to the application of the main pulse. The optimal performance of the MPOS+MID system was realized at the level of ZMPOS/ZMID = 2.5. The energy of the extracted high-power ion beam made up 3.5 kJ, its power being 120 GW with 40% efficiency of energy transfer from MPOS to the MID.

  18. Real-time simulation of missile efflux plasma based on Vega Prime & OpenGL%Vega Prime结合OpenGL的导弹尾焰实时模拟

    Institute of Scientific and Technical Information of China (English)

    李威; 杨峰; 程咏梅; 杨衍波

    2012-01-01

    It researches missile operational system simulation experiment, in view of the problem that when using Vega Prime' s particle system module for the simulation of missile efflux plasma which is moving with high speed, the particles are discrete that impact the simulation visualization effect. In order to solve the missile efflux plasma simulation problem, it proposes the solution that using Vega Prime together with OpenGL. It models the missile efflux plasma based on the particle system principle, applies OpenGL into Vega Prime according to the event issued subscription mechanism of Vega Prime. The efflux plasma that simulated by the proposed method is shape lifelike and sporty. It meets the demands of the instantaneity and authenticity in the simulation and solves the defect of simulating missile efflux plasma by Vega Prime.%研究基于Vega Prime的导弹作战系统仿真实验,针对使用Vega Prime的粒子特效模拟高速飞行导弹尾焰会出现尾焰不连续而影响仿真可视化效果的问题,提出将Vega Prime与OpenGL相结合的方法.基于粒子系统基本原理,对导弹尾焰进行建模;依据Vega Prime的事件发布订阅机制将OpenGL引入到Vega Prime中.模拟的尾焰形态逼真,动感十足,满足仿真实时性与真实性要求,解决了Vega Prime模拟导弹尾焰存在缺陷的问题.

  19. Computation of the spectrum of spatial Lyapunov exponents for the spatially extended beam-plasma systems and electron-wave devices

    CERN Document Server

    Hramov, Alexander E; Maximenko, Vladimir A; Moskalenko, Olga I; 10.1063/1.4740063

    2013-01-01

    The spectrum of Lyapunov exponents is powerful tool for the analysis of the complex system dynamics. In the general framework of nonlinear dynamical systems a number of the numerical technics have been developed to obtain the spectrum of Lyapunov exponents for the complex temporal behavior of the systems with a few degree of freedom. Unfortunately, these methods can not apply directly to analysis of complex spatio-temporal dynamics in plasma devices which are characterized by the infinite phase space, since they are the spatially extended active media. In the present paper we propose the method for the calculation of the spectrum of the spatial Lyapunov exponents (SLEs) for the spatially extended beam-plasma systems. The calculation technique is applied to the analysis of chaotic spatio-temporal oscillations in three different beam-plasma model: (1) simple plasma Pierce diode, (2) coupled Pierce diodes, and (3) electron-wave system with backward electromagnetic wave. We find an excellent agreement between the...

  20. Modelling of impurity transport and plasma-wall interaction in fusion devices with the ERO code: basics of the code and examples of application

    Energy Technology Data Exchange (ETDEWEB)

    Kirschner, A.; Borodin, D.; Brezinsek, S.; Linsmeier, C.; Romazanov, J. [Forschungszentrum Juelich GmbH, Institut fuer Energie- und Klimaforschung - Plasmaphysik, Juelich (Germany); Tskhakaya, D. [Fusion rate at OeAW, Institute of Applied Physics, TU Wien (Austria); Institute of Theoretical Physics, University of Innsbruck (Austria); Kawamura, G. [National Institute for Fusion Science, Gifu (Japan); Ding, R. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China)

    2016-08-15

    The 3D ERO code, which simulates plasma-wall interaction and impurity transport in magnetically confined fusion-relevant devices is described. As application, prompt deposition of eroded tungsten has been simulated at surfaces with shallow magnetic field of 3 T. Dedicated PIC simulations have been performed to calculate the characteristics of the sheath in front of plasma-exposed surfaces to use as input for these ERO simulations. Prompt deposition of tungsten reaches 100% at the highest electron temperature and density. In comparison to more simplified assumptions for the sheath the amount of prompt deposition is in general smaller if the PIC-calculated sheath is used. Due to friction with the background plasma the impact energy of deposited tungsten can be significantly larger than the energy gained in the sheath potential. (copyright 2016 The Authors. Contributions to Plasma Physics published by Wiley-VCH Verlag GmbH and Co. KGaA Weinheim. This)

  1. Pathway to a compact SASE FEL device

    Energy Technology Data Exchange (ETDEWEB)

    Dattoli, G., E-mail: giuseppe.dattoli@enea.it [ENEA – Centro Ricerche Frascati, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Di Palma, E. [ENEA – Centro Ricerche Frascati, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Petrillo, V. [Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy); Rau, Julietta V. [Istituto di Struttura della Materia, ISM-CNR, Via del Fosso del Cavaliere, 100-00133 Rome (Italy); Sabia, E.; Spassovsky, I. [ENEA – Centro Ricerche Frascati, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Biedron, S.G.; Einstein, J.; Milton, S.V. [CSU – Colorado State University, Fort Collins, CO (United States)

    2015-10-21

    Newly developed high peak power lasers have opened the possibilities of driving coherent light sources operating with laser plasma accelerated beams and wave undulators. We speculate on the combination of these two concepts and show that the merging of the underlying technologies could lead to new and interesting possibilities to achieve truly compact, coherent radiator devices.

  2. Pathway to a Compact SASE FEL Device

    CERN Document Server

    Dattoli, G; Petrillo, V; Rau, J V; Sabia, E; Spassovsky, I; Biedron, S G; Einstein, J; Milton, S V

    2015-01-01

    Newly developed high peak power lasers have opened the possibilities of driving coherent light sources operating with laser plasma accelerated beams and wave undulators. We speculate on the combination of these two concepts and show that the merging of the underlying technologies could lead to new and interesting possibilities to achieve truly compact, coherent radiator devices.

  3. Impact of Atmospheric Plasma Generated by a DBD Device on Quality-Related Attributes of "Abate Fetel" Pear Fruit

    Science.gov (United States)

    Berardinelli, Annachiara; Vannini, Lucia; Ragni, Luigi; Guerzoni, M. Elisabetta

    The effects of gas plasma generated by a Dielectric Barrier Discharge (DBD) device on "Abate Fetel" fresh pears were assessed following exposure times from 10 to 90 min. In particular the decontamination efficacy towards the indigenous microflora naturally occurring on the surface of the fruit was evaluated. The main results showed that total mesophilic bacteria, yeasts and moulds had different inactivation dynamics. However, maximum cell decreases of 2.5 Log CFU/fruit were achieved for all the microbial groups after 90 min of treatment at a relative humidity level of 60% (22°C). Immediately after the treatments, no significant effects were observed on the measured quality traits. After storage for 5 days at 20°C significant changes were detected only in the peel (colour and antioxidant capacity) of fruit samples treated for 90 min. The Magness-Taylor flesh firmness (MTf), the soluble solid content (SSC) and the antioxidant capacity of fruits were unaffected by the tested treatments.

  4. Deposition of magnesium nitride thin films on stainless steel-304 substrates by using a plasma focus device

    Science.gov (United States)

    Ramezani, Amir Hoshang; Habibi, Maryam; Ghoranneviss, Mahmood

    2014-08-01

    In this research, for the first time, we synthesize magnesium nitride thin films on 304-type stainless steel substrates using a Mather-type (2 kJ) plasma focus (PF) device. The films of magnesium nitride are coated with different number of focus shots (like 15, 25 and 35) at a distance of 8 cm from the anode tip and at 0° angular position with respect to the anode axis. For investigation of the structural properties and surface morphology of magnesium nitride films, we utilized the X-ray diffractometer (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis, respectively. Also, the elemental composition is characterized by energy-dispersive X-ray (EDX) analysis. Furthermore, Vicker's microhardness is used to study the mechanical properties of the deposited films. The results show that the degree of crystallinity of deposited thin films (from XRD), the average size of particles and surface roughness (from AFM), crystalline growth of structures (from SEM) and the hardness values of the films depend on the number of focus shots. The EDX analysis demonstrates the existence of the elemental composition of magnesium in the deposited samples.

  5. Deposition of Chromium Thin Films on Stainless Steel-304 Substrates Using a Low Energy Plasma Focus Device

    Science.gov (United States)

    Javadi, S.; Ghoranneviss, M.; Hojabri, A.; Habibi, M.; Hosseinnejad, M. T.

    2012-06-01

    In this paper, we study thin films of chromium deposited on stainless steel-304 substrates using a low energy (1.6 kJ) plasma focus device. The films of chromium are likewise deposited with 25 focus shots each at various axial distances from the top of the anode (3, 5, 7, 9 and 11 cm). We also consider different angular positions with respect to the anode axis (0°, 15° and 30°) at a distance of 5 cm from the anode tip to deposit the chromium films on the stainless steel substrates. To characterize the structural properties of the films, we benefit from X-ray diffraction (XRD) analysis. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) are applied as well to study the surface morphology of these deposited films. Furthermore, we make use of Vicker's micro-hardness measurements to investigate the mechanical properties of chromium thin films. The XRD results show that the degree of crystallinity of chromium thin films depends on the substrate axial and angular positions. The AFM images illustrate that the film deposited at the distance of 5 cm and the angular position of 0° has quite a uniform surface with homogeneous distribution of grains on the film surface. From the hardness results, we observe that the sample deposited at the axial distance of 5 cm from the anode tip and at the angle of 0° with respect to the anode axis, is harder than the other deposited films.

  6. Platelet-Rich Plasma in the Treatment of Subcutaneous Venous Access Device Scars: A Head-to-Head Patient Survey

    Directory of Open Access Journals (Sweden)

    C. Eichler

    2015-01-01

    Full Text Available Introduction. Platelet-rich plasma (PRP is a product widely used in sports medicine, tissue repair, and general surgery. A recent meta-analysis showed this product to be beneficial when introduced into a wound area, be it intra-articular (i.e., joint-injections or direct introduction onto the wound surface. Methods. Between the years of 2012 and 2014 a questionnaire evaluating surgical outcome after port (venous access device removal was answered by 100 patients in the control group and 20 patients in a PRP group, leading to a total of 120 patients in this single center, retrospective, subjective outcome evaluation. Results. No statistical difference was shown in postsurgical complication rates, postsurgical pain, decreased mobility, and overall quality of life. A significant difference was shown in overall patient satisfaction and the desire to further improve port area scarring. Results differed significantly in favor of the PRP group. Interestingly, approximately 40.2% of patients are dissatisfied with the surgical outcome after port removal in the control group. This result, though surprising, may be improved to 10% dissatisfaction when a PRP product is used. Conclusion. PRP products such as Arthrex ACP are safe to use and present an additional option in improving surgical outcome.

  7. The Role of Subjective Well-Being in Co-Designing Open-Design Assistive Devices; design case study

    NARCIS (Netherlands)

    De Couvreur, L.; Dejonghe, W.; Detand, J.; Goossens, R.

    2013-01-01

    In this paper we explore the role of subjective well-being within the process of making together a personalized assistive device. Through a process of social product adaptation, assistive artifacts become part of occupational therapy and co-evolve with clients. Personal digital fabrication tools ena

  8. Magnetic Fusion Energy Plasma Interactive and High Heat Flux Components: Volume 5, Technical assessment of critical issues in the steady state operation of fusion confinement devices

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    Critical issues for the steady state operation of plasma confinement devices exist in both the physics and technology fields of fusion research. Due to the wide range and number of these issues, this technical assessment has focused on the crucial issues associated with the plasma physics and the plasma interactive components. The document provides information on the problem areas that affect the design and operation of a steady state ETR or ITER type confinement device. It discusses both tokamaks and alternative concepts, and provides a survey of existing and planned confinement machines and laboratory facilities that can address the identified issues. A universal definition of steady state operation is difficult to obtain. From a physics point of view, steady state is generally achieved when the time derivatives approach zero and the operation time greatly exceeds the characteristic time constants of the device. Steady state operation for materials depends on whether thermal stress, creep, fatigue, radiation damage, or power removal are being discussed. For erosion issues, the fluence and availability of the machine for continuous operation are important, assuming that transient events such as disruptions do not limit the component lifetimes. The panel suggests, in general terms, that steady state requires plasma operation from 100 to 1000 seconds and an availability of more than a few percent, which is similar to the expectations for an ETR type device. The assessment of critical issues for steady state operation is divided into four sections: physics issues; technology issues; issues in alternative concepts; and devices and laboratory facilities that can address these problems.

  9. Development of open air silicon deposition technology by silane-free atmospheric pressure plasma enhanced chemical transport under local ambient gas control

    Science.gov (United States)

    Naito, Teruki; Konno, Nobuaki; Yoshida, Yukihisa

    2016-07-01

    Open air silicon deposition was performed by combining silane-free atmospheric pressure plasma-enhanced chemical transport and a newly developed local ambient gas control technology. The effect of air contamination on silicon deposition was investigated using a vacuum chamber, and the allowable air contamination level was confirmed to be 3 ppm. The capability of the local ambient gas control head was investigated numerically and experimentally. A safe and clean process environment with air contamination less than 1 ppm was achieved. Combining these technologies, a microcrystalline silicon film was deposited in open air, the properties of which were comparable to those of silicon films deposited in a vacuum chamber.

  10. A Fault-Tolerant Modulation Method to Counteract the Double Open-Switch Fault in Matrix Converter Drive Systems without Redundant Power Devices

    DEFF Research Database (Denmark)

    Chen, Der-Fa; Nguyen-Duy, Khiem; Liu, Tian-Hua

    2012-01-01

    redundant physical connections. It is shown that different locations of the double open switch affect the availability of the revised modulation. The steady state absolute speed error achieved with the proposed method is 4% of the nominal speed. Experimental results are performed to demonstrate the efficacy......-stage modulation is adjusted based on the knowledge of the switching logics of the inverter-stage and the operating input voltage sectors. However, the proposed fault-tolerant method does not rely on the assist of any redundant power devices or any reconfiguration of the matrix converter circuit by means of using...... of the proposed methods....

  11. Long-term exposure to electromagnetic radiation from mobile phones and Wi-Fi devices decreases plasma prolactin, progesterone, and estrogen levels but increases uterine oxidative stress in pregnant rats and their offspring.

    Science.gov (United States)

    Yüksel, Murat; Nazıroğlu, Mustafa; Özkaya, Mehmet Okan

    2016-05-01

    Wi-Fi devices. It is likely that TRPV1-mediated Ca(2+) entry in the uterus of pregnant rats involves accumulation of oxidative stress and opening of mitochondrial membrane pores that consequently leads to mitochondrial dysfunction, substantial swelling of the mitochondria with rupture of the outer membrane and release of oxidants such as superoxide (O2 (-)) and hydrogen peroxide (H2O2). The superoxide radical is converted to H2O2 by superoxide dismutase (SOD) enzyme. Glutathione peroxidase (GSH-Px) is an important antioxidant enzyme for removing lipid hydroperoxides and hydrogen peroxide and it catalyzes the reduction of H2O2 to water.

  12. Impacts of plasma-induced damage due to UV light irradiation during etching on Ge fin fabrication and device performance of Ge fin field-effect transistors

    Science.gov (United States)

    Mizubayashi, Wataru; Noda, Shuichi; Ishikawa, Yuki; Nishi, Takashi; Kikuchi, Akio; Ota, Hiroyuki; Su, Ping-Hsun; Li, Yiming; Samukawa, Seiji; Endo, Kazuhiko

    2017-02-01

    We investigated the impacts of plasma-induced damage due to UV light irradiation during etching on Ge fin fabrication and the device performance of Ge fin field-effect transistors (Ge FinFETs). UV light irradiation during etching affected the shape of the Ge fin and the surface roughness of the Ge fin sidewall. A vertical and smooth Ge fin could be fabricated by neutral beam etching without UV light irradiation. The performances of Ge FinFETs fabricated by neutral beam etching were markedly improved as compared to those of Ge FinFETs fabricated by inductively coupled plasma etching, in which the UV light has an impact.

  13. Magnetoresistive waves in plasmas

    Science.gov (United States)

    Felber, F. S.; Hunter, R. O., Jr.; Pereira, N. R.; Tajima, T.

    1982-10-01

    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed.

  14. Injection barrel with a tapered structure for a low speed and small size cryogenic hydrogen pellet in medium-sized plasma fusion devices

    Science.gov (United States)

    Motojima, G.; Sakamoto, R.; Okada, H.; Nagasaki, K.; Yamada, H.; Nakamura, Y.; Kado, S.; Kobayashi, S.; Konoshima, S.; Minami, T.; Ohshima, S.; Yamamoto, S.; Mizuuchi, T.; Mutoh, T.

    2016-10-01

    An injection barrel was designed and fabricated for a small size 0.8 mm cryogenic pellet with a low speed of 200-300 m/s in medium-sized plasma fusion devices. Pellet injection with pneumatic acceleration was examined using a conventional in situ technique. A tapered structure was applied in the downstream side of the injection barrel to satisfy the requirement of pellet speed reduction by expansion of the propellant gas. Shadowgraph and light gate measurements show that the intact pellets have speeds of 260 ± 30 m/s and a typical size of 1.1-1.2 mm. The pellet ablation code based on a neutral gas shielding model shows that the penetration depth of the measured pellet parameters does not cross the plasma center, even in medium-sized plasma devices such as the Heliotron J helical device. The injection barrel with a tapered structure developed in this study is feasible for low speed pellet injection.

  15. Injection barrel with a tapered structure for a low speed and small size cryogenic hydrogen pellet in medium-sized plasma fusion devices.

    Science.gov (United States)

    Motojima, G; Sakamoto, R; Okada, H; Nagasaki, K; Yamada, H; Nakamura, Y; Kado, S; Kobayashi, S; Konoshima, S; Minami, T; Ohshima, S; Yamamoto, S; Mizuuchi, T; Mutoh, T

    2016-10-01

    An injection barrel was designed and fabricated for a small size 0.8 mm cryogenic pellet with a low speed of 200-300 m/s in medium-sized plasma fusion devices. Pellet injection with pneumatic acceleration was examined using a conventional in situ technique. A tapered structure was applied in the downstream side of the injection barrel to satisfy the requirement of pellet speed reduction by expansion of the propellant gas. Shadowgraph and light gate measurements show that the intact pellets have speeds of 260 ± 30 m/s and a typical size of 1.1-1.2 mm. The pellet ablation code based on a neutral gas shielding model shows that the penetration depth of the measured pellet parameters does not cross the plasma center, even in medium-sized plasma devices such as the Heliotron J helical device. The injection barrel with a tapered structure developed in this study is feasible for low speed pellet injection.

  16. The collision frequency model of the solid state plasma for Si/Si1-xGex/Si SPiN device

    Science.gov (United States)

    Kang, H. Y.; Hu, H. Y.; Wang, B.; Zhang, H. M.; Su, H.; Hao, M. R.

    2017-01-01

    A two dimensional(2D) collision frequency model is developed based on the 2D solid state plasma concentration distribution model and mobility model for a heterogeneous Si/Si1-xGex/Si structure SPiN(Surface PiN) devices, which are the basic radiating elements in the reconfigurable solid state plasma antenna. The lower collision frequency can be achieved when the Ge mole fraction x and applied voltage increase at the temperature T=300 K, and that the basically uniform distribution of collision frequency can be obtained for Ge mole fraction x=0.3. Moreover, radiation efficiency and the maximum gain of the antenna for the different collision frequency have also been studied. The proposed model can be a handful for the designing of the solid state plasma antenna.

  17. Characterization of the Plasma Edge for Technique of Atomic Helium Beam in the CIEMAT Fusion Device; Caracterizacion del Borde del Plasma del Dispositivo de Fusion TJ-II del CIEMAT mediante el Diagnostico del Haz Supersonico de Helio

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo, A.

    2003-07-01

    In this report, the measurement of Electron Temperature and Density in the Boundary Plasma of TJ-II with a Supersonic Helium Beam Diagnostic and work devoted to the upgrading of this technique are described. Also, simulations of Laser Induced Fluorescence (LIF) studies of level populations of electronically excited He atoms are shown. This last technique is now being installed in the CIEMAT fusion device. (Author ) 36 refs.

  18. Open and closed-loop control of transonic buffet on 3D turbulent wings using fluidic devices

    Science.gov (United States)

    Dandois, Julien; Lepage, Arnaud; Dor, Jean-Bernard; Molton, Pascal; Ternoy, Frédéric; Geeraert, Arnaud; Brunet, Vincent; Coustols, Éric

    2014-06-01

    This paper presents an overview of the work performed recently at ONERA on the control of the buffet phenomenon. This aerodynamic instability induces strong wall pressure fluctuations and as such limits aircraft envelope; consequently, it is interesting to try to delay its onset, in order to enlarge aircraft flight envelop, but also to provide more flexibility during the design phase. Several types of flow control have been investigated, either passive (mechanical vortex generators) or active (fluidic VGs, fluidic trailing-edge device (TED)). It is shown than mechanical and fluidic VGs are able to delay buffet onset in the angle-of-attack domain by suppressing the separation downstream of the shock. The effect of the fluidic TED is different, the separation is not suppressed, but the rear wing loading is increased and consequently the buffet onset is not delayed to higher angles of attack, but only to higher lift coefficient. Then, a closed loop control methodology based on a quasi-static approach is defined and several architectures are tested for various parameters such as the input signal, the objective function or, the tuning of the feedback gain. All closed loop methods are implemented on a dSPACE device calculating in real time the fluidic actuators command from the unsteady pressure sensors data.

  19. Plasma from the second and third weeks after open colorectal resection for cancer stimulates in vitro endothelial cell growth, migration, and invasion.

    Science.gov (United States)

    Shantha Kumara, H M C; Kirchoff, Daniel; Naffouje, Samer; Grieco, Michael; Herath, Sonali A C; Dujovny, Nadav; Kalady, Matthew F; Hyman, Neil; Njoh, Linda; Whelan, Richard L

    2012-03-01

    Angiogenesis is central to wound healing and tumor growth. Postoperative (postop) plasma from weeks 2 and 3 after minimally invasive colorectal resection (MICR) stimulates endothelial cell (EC) migration (MIG), invasion (INV), and proliferation (all vital to angiogenesis) compared with preoperative (preop) plasma results and may promote postop tumor growth. The purpose of this study was to determine whether plasma from open colorectal resection (OCR) patients has similar proangiogenic EC effects in vitro. OCR cancer patient plasma from institutional review board-approved banks was used; patients with preop and one postop sample from postoperative days (POD) 7-33 were eligible. Samples were bundled into 7- to 13-day periods and considered as single time points. In vitro cultures of human umbilical venous ECs were used for the EC proliferation (BPF, Branch Point Formation), INV, and MIG assays performed with preop, POD 7-13, POD 14-20, and POD 21-33 plasma. Data were analyzed by paired t test and were reported as mean ± standard deviation (significance, P MICR results were largely similar. Tumor angiogenesis may be stimulated after OCR and MICR for 3 weeks. Further studies are warranted.

  20. FAST TRACK COMMUNICATION: Self-patterned aluminium interconnects and ring electrodes for arrays of microcavity plasma devices encapsulated in Al2O3

    Science.gov (United States)

    Kim, K. S.; Park, S.-J.; Eden, J. G.

    2008-01-01

    Automatic formation of Al interconnects and ring electrodes, fully encapsulated by alumina, in planar arrays of Al2O3/Al/Al2O3 microcavity plasma devices has been accomplished by electrochemical processing of Al foil. Following the fabrication of cylindrical microcavities (50-350 µm in diameter) in 127 µm thick Al foil, virtually complete anodization of the foil yields azimuthally symmetric Al electrodes surrounding each cavity and interconnects between adjacent microcavities that are produced and simultaneously buried within a transparent Al2O3 film without the need for conventional patterning techniques. The diameter and pitch of the microcavities prior to anodization, as well as the anodization process parameters, determine which of the microcavity plasma devices in a one- or two-dimensional array are connected electrically. Data presented for 200 µm diameter cavities with a pitch of 150-225 µm illustrate the patterning of the interconnects and electrode connectivity after 4-10 h of anodization in oxalic acid. Self-patterned, linear arrays comprising 25 dielectric barrier devices have been excited by a sinusoidal or bipolar pulse voltage waveform and operated in 400-700 Torr of rare gas. Owing to the electrochemical conversion of most of the Al foil into Al2O3, the self-formed arrays exhibit an areal capacitance ~82% lower than that characteristic of previous Al/Al2O3 device arrays (Park et al 2006 J. Appl. Phys. 99 026107).

  1. Properties of highly electronegative plasmas produced in a multipolar magnetic-confined device with a transversal magnetic filter

    DEFF Research Database (Denmark)

    Draghici, Mihai; Stamate, Eugen

    2010-01-01

    electrodes on plasma parameters, the formation of the negative ion sheath and etching rates by positive and negative ions have been investigated for different experimental conditions. When the electron temperature was reduced below 1 eV the density ratio of negative ion to electron exceeded 100 even for very......Highly electronegative plasmas were produced in Ar/SF6 gas mixtures in a dc discharge with multipolar magnetic confinement and transversal magnetic filter. Langmuir probe and mass spectrometry were used for plasma diagnostics. Plasma potential drift, the influence of small or large area biased...... low amounts of SF6 gas. The plasma potential drift could be controlled by proper wall conditioning. A large electrode biased positively had no effect on plasma potential for density ratios of negative ions to electrons larger than 50. For similar electronegativities or higher a negative ion sheath...

  2. A new numerical description of the interaction of an ion beam with a magnetized plasma in an ECR-based charge breeding device

    Science.gov (United States)

    Galatà, A.; Mascali, D.; Neri, L.; Celona, L.

    2016-08-01

    The ion beam-plasma interaction is a relevant topic in several fields of plasma physics, from fusion devices to modern ion sources. This paper discusses the numerical modelling of the whole beam-plus-plasma-target system in case of 1+  ions entering an ECR-based charge breeder (ECR-CB). The model is able to reproduce the ion capture and the creation of the first charge states in the selected physics case, i.e. the interaction of a 85Rb1+ ions with the plasma of the 14.5 GHz PHOENIX ECR-CB installed at the Laboratoire de Physique Subatomique et de Cosmologie (LPSC) of Grenoble. The results show that a very narrow window of physical parameters for both the beam (energy and energy spread especially) and plasma (ion temperature, density, density structural distribution, self-generated ambipolar fields) exists which is able to reproduce very well the experimental results, providing an exhaustive picture of the involved phenomena. Possible non-linear interactions and the role played by the eventual onset of instabilities are also discussed.

  3. Fundamental processes of plasma and reactive gas surface treatment for the recovery of hydrogen isotopes from carbon co-deposits in fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Soeren

    2014-11-01

    The use of carbon-based plasma-facing wall components offers many advantages for plasma operation in magnetic confinement nuclear fusion devices. However, through reactions with the hydrogen based fusion plasma, carbon forms amorphous hydrogenated carbon co-deposits (a-C:H) in the vacuum vessels. If tritium is used to fuel the reactor, this co-deposition can quickly lead to an inacceptable high tritium inventory. Through co-deposition with carbon about 10% of the tritium injected into the reactor can be trapped. Even with other wall materials co-deposition can be significant. A method to recover the hydrogen isotopes from the co-deposits is necessary. The method has to be compatible with the requirements of the devices and nuclear fusion plasma operation. In this work thermo-chemical removal by neutral gases (TCR) and removal by plasmas is investigated. Models are developed to describe the involved processes of both removal methods. TCR is described using a reaction-diffusion model. Within this model the reactive gas diffuses into the co-deposits and subsequently reacts in a thermally activated process. The co-deposits are pyrolysed, forming volatile gases, e.g. CO{sub 2} and H{sub 2}O. These gases are pumped from the vacuum vessel and recycled. Applying the model to literature observations enables to connect data on exposure temperature, pressure, time and co-deposit properties. Two limits of TCR (reaction- or diffusion-limited) are identified. Plasma removal sputters co-deposits by their chemical and physical interaction with the impinging ions. The description uses a 0D plasma model from the literature which derives plasma parameters from the balance of input power to plasma power losses. The model is extended with descriptions of the plasma sheath and ion-surface interactions to derive the co-deposit removal rates. Plasma removal can be limited by this ion induced surface release rate or the rate of pumping of the released species. To test the models dedicated

  4. Measurement of performance parameters of plasma source for plasma opening switch on Qiangguang-Ⅰ generator%强光一号POS等离子体源性能参数测量

    Institute of Scientific and Technical Information of China (English)

    罗维熙; 曾正中; 雷天时; 王亮平; 呼义翔; 孙铁平; 黄涛

    2012-01-01

    以强光一号等离子体源(电缆枪)为研究对象,采用电荷收集器(法拉第杯)对强光一号等离子体源性能参数进行测量.实验结果表明:等离子体发射密度与电缆等离子体枪枪芯到枪口的距离正相关,而发射速度与电缆等离子体枪枪芯到枪口的距离负相关;增大电缆枪驱动电压时,等离子体发射密度增速远小于驱动电流增速.重复性研究表明,对由数十支电缆枪组成的等离子体源而言,单支电缆枪放电分散性对其输出等离子体整体分布均匀性影响不大.不确定度分析表明,通过多次重复实验求平均值,可以有效减小实验结果的不确定度,发射密度测量结果的合成标准不确定度在10%以内.%The plasma source (cable guns) of the plasma opening switch(POS) on Qiangguang I generator was chosen as the study object. The plasma source performance was investigated by using charge collectors. Experimental results show that the plasma ejection density is positively correlated with the structural parameter, the distance between gun core tip and muzzle plane, and the plasma ejection velocity is negatively correlated with the parameter. The increasing rate of plasma ejection density is less than that of drive current. As far as a plasma source with tens of cable plasma guns is concerned, the influence of single cable gun's discharge dispersancy on plasma uniformity is little. Analysis of uncertainty shows that the uncertainty of measurement can be reduced by increasing the number of experiments and averaging the results. The combined standard uncertainty of plasma ejection density is less than 10%.

  5. Development of Open Type Microwave Plasma Source%开放式微波等离子体源的研究进展

    Institute of Scientific and Technical Information of China (English)

    王仲; 张贵新; 王强

    2011-01-01

    微波等离子体由于无电极污染、能在大气压下产生及电子密度大等一系列优点而具有较好的工业应用前景.因此大气压下开放式微波等离子体源的研究已经成为实现相关工业应用价值的关键.从最初的能够激发低气压空气微波等离子体的APMPS-Ⅰ型微波等离子体源的研究开始,逐步通过增加某些辅助设备或改进微波反应腔的尺寸和结构,历经APMPS+JET型、APMPS-Ⅱ型最终到平行直线矩形波导微波等离子体反应腔,实现了大气压开放式微波等离子体的激发.同时,对各种微波等离子体源的原理和相关特性进行了全面阐述,在此基础上对激发出的空气微波等离子体的形态进行了分析,说明了在一定的微波功率范围内较为稳定均匀的大气压开放式空气微波等离子体的实现是具有可行性的.%Microwave plasma holds some promise in practical applications due to a series of advantages such as free from contamination by electrodes, the possibility of generation at atmosphere pressure, high electron density and so on. Therefore, the study on atmosphere open microwave plasma source is key to the realization of related industrial application value. First, we research the APMPS-Itype microwave plasma source that can excite air microwave plas ma at low pressure, successively through APMPS+JET type, APMPS-II type, we finally reach the design of paral lel rectilinear rectangle waveguide microwave plasma reactor by the addition of auxiliary equipment called ionization jet or the improvement of the dimensions and structure of reactor cavity in our laboratory. And the excitation of at mosphere open type air microwave plasma can be realized by means of the reactors above. The distribution of elec tric-field strength in ail kinds of cavities is simulated by a kind of simulation software named CST. Also the principle and relevant characteristics of all kinds of microwave plasma source are elaborated

  6. An open prospective study evaluating efficacy and safety of a new medical device for rectal application of activated carbon in the treatment of chronic, uncomplicated perianal fistulas

    DEFF Research Database (Denmark)

    Zawadzki, Antoni; Johnson, Louis Banka; Bohe, Måns;

    2017-01-01

    PURPOSE: It has been proposed that biological/chemical substances in the intestine might play a role in the occurrence and deterioration of perianal fistulas. Elimination of such unidentified factors from the lower gastrointestinal tract might offer a new strategy for the management of anal...... fistulas. The aim of this study was to evaluate the clinical effects on non-Crohn's disease perianal fistula healing, and the safety and tolerability of a new medical device that applies high-purity, high-activity granular activated carbon locally into the rectum twice daily of patients with perianal...... fistulas without any concomitant medication. METHODS: An open, single-arm, prospective study with active treatment for 8 weeks and an optional follow-up until week 24 ( ClinicalTrial.gov identifier NCT01462747) among patients with chronic, uncomplicated perianal fistulas scheduled for surgery was conducted...

  7. An open prospective study evaluating efficacy and safety of a new medical device for rectal application of activated carbon in the treatment of chronic, uncomplicated perianal fistulas

    DEFF Research Database (Denmark)

    Zawadzki, Antoni; Johnson, Louis Banka; Bohe, Måns

    2017-01-01

    PURPOSE: It has been proposed that biological/chemical substances in the intestine might play a role in the occurrence and deterioration of perianal fistulas. Elimination of such unidentified factors from the lower gastrointestinal tract might offer a new strategy for the management of anal...... fistulas. The aim of this study was to evaluate the clinical effects on non-Crohn's disease perianal fistula healing, and the safety and tolerability of a new medical device that applies high-purity, high-activity granular activated carbon locally into the rectum twice daily of patients with perianal...... fistulas without any concomitant medication. METHODS: An open, single-arm, prospective study with active treatment for 8 weeks and an optional follow-up until week 24 ( ClinicalTrial.gov identifier NCT01462747) among patients with chronic, uncomplicated perianal fistulas scheduled for surgery was conducted...

  8. Management of pleural empyema with a vacuum-assisted closure device and reconstruction of open thoracic window in a patient with liver cirrhosis.

    Science.gov (United States)

    Munguía-Canales, Daniel Alejandro; Vargas-Mendoza, Gary Kosai; Alvarez-Bestoff, Gustavo; Calderón-Abbo, Moisés Cutiel

    2013-10-01

    The patient is a 21-year-old female, diagnosed with cryptogenic cirrhosis at the age of 9. She presented with left post-pneumonic empyema that did not remit with conventional medical management and evolved with fistulization to the skin in the 7th intercostal space in the left subscapular region. We performed an open thoracic window procedure, and on the 6th day the patient was sent home with a portable vacuum-assisted closure device, with changes of the material every 4 days until the cavity was completed obliterated (92 days). Imaging tests showed full expansion of the lung, and chest wall reconstruction was performed with titanium rods. The high mortality of empyema in patients with liver disease requires both implementing and searching for new adjuvant therapies, like the use of vacuum-assisted closure systems and reconstruction with titanium rods. Controlled studies with a wide range of cases are needed for proper evaluation.

  9. Discussion Design of Mechanical Opening Door Device%一种机械式开门装置设计的探讨

    Institute of Scientific and Technical Information of China (English)

    吕俊

    2012-01-01

    机械开门装置因其具备良好的耐用性和可靠性等特点而被广泛地使用在工程领域中。介绍的一种机械开门装置采用操纵软轴配备连杆机构的结构模式,可作为矿井提升机结构设计的参考。该装置结构简单、操纵灵活,可确保门扇的安全开闭。%The mechanical door operator is widely used in engineering industry with the features of good durability and reliability. The mechanical door operator which is introduced adopts the structure model of manipulation soft bearing with linkage mode, suitable for mine hoist. The device structure is simple, flexible operation, to ensure the safety door open of hoist.

  10. Outcomes and stability in patients with anterior open bite and long anterior face height treated with temporary anchorage devices and a maxillary intrusion splint

    Science.gov (United States)

    Scheffler, Nicole R.; Proffit, William R.; Phillips, Ceib

    2015-01-01

    Introduction Temporary skeletal anchorage devices now offer the possibility of closing anterior open bites and decreasing anterior face height by intruding maxillary posterior teeth, but data for treatment outcomes are lacking. This article presents outcomes and posttreatment changes for consecutive patients treated with a standardized technique. Methods The sample included 33 consecutive patients who had intrusion of maxillary posterior teeth with a maxillary occlusal splint and nickel-titanium coil springs to temporary anchorage devices in the zygomatic buttress area, buccal and apical to the maxillary molars. Of this group, 30 had adequate cephalograms available for the period of treatment, 27 had cephalograms including 1-year posttreatment, and 25 had cephalograms from 2 years or longer. Results During splint therapy, the mean molar intrusion was 2.3 mm. The mean decrease in anterior face height was 1.6 mm, less than expected because of a 0.6-mm mean eruption of the mandibular molars. During the postintrusion orthodontics, the mean change in maxillary molar position was a 0.2-mm extrusion, and there was a mean 0.5-mm increase in face height. Positive overbite was maintained in all patients, with a slight elongation (<2 mm) of the incisors contributing to this. During the 1 year of posttreatment retention, the mean changes were a further eruption of 0.5 mm of the maxillary molars, whereas the mandibular molars intruded by 0.6 mm, and there was a small decrease in anterior face height. Changes beyond 1 year posttreatment were small and attributable to growth rather than relapse in tooth positions. Conclusions Intrusion of the maxillary posterior teeth can give satisfactory correction of moderately severe anterior open bites, but 0.5 to 1.5 mm of reeruption of these teeth is likely to occur. Controlling the vertical position of the mandibular molars so that they do not erupt as the maxillary teeth are intruded is important in obtaining a decrease in face height

  11. The effects of pre-ionization using a shunt resistor on reproducibility of the x-ray emission in a dense plasma focus device

    Science.gov (United States)

    Piriaei, D.; Yousefi, H. R.; Mahabadi, T. D.; SalarElahi, A.; Ghoranneviss, M.

    2017-08-01

    In this research, the effects of pre-ionization using a shunt resistor on reproducibility of x-ray emission in a Mather type plasma focus device have been studied. This technique increased the intensities of the emitted x-rays from argon as the filling gas of the device and made the x-ray yields with similar intensities reproducible. A Mirnov coil was also used to record the variations of the plasma's magnetic field, and the wavelet spectrums of these recorded signals showed the reduced instabilities due to the application of the pre-ionization technique. Moreover, it was demonstrated that this technique was capable of reducing the number of initial runaway electrons that could increase the impurities and instabilities inside the plasma. In addition to the above-mentioned features, this technique could improve the uniform formation of the current sheath during the breakdown phase that might later lead to a high quality pinch and high intensity emitted x-rays.

  12. Usefulness of early diastolic mitral annular velocity to predict plasma levels of brain natriuretic peptide and transient heart failure development after device closure of atrial septal defect.

    Science.gov (United States)

    Masutani, Satoshi; Taketazu, Mio; Mihara, Chihiro; Mimura, Yuko; Ishido, Hirotaka; Matsunaga, Tamotsu; Kobayashi, Toshiki; Senzaki, Hideaki

    2009-12-15

    Device closure of atrial septal defect (ASD) is sometimes followed by elevation of plasma brain natriuretic peptide (BNP), a marker of heart failure, and progression to heart failure. This study tested the hypothesis that the underlying diastolic dysfunction, assessed on tissue Doppler images (TDI) before device closure, can predict BNP level after ASD closure. The study subjects were 39 consecutive patients (age 27.5 +/- 16.3 years, range 5 to 63) who underwent device closure for ASD. Echocardiographic evaluation using TDI and 2-dimensional and pulse wave Doppler were performed, together with plasma BNP measurement 1 day before and 2 days after ASD closure. Before ASD closure, an age-dependent decrease was noted in left ventricular relaxation, assessed by early diastolic mitral annular velocity. ASD closure resulted in a decrease in early diastolic mitral annular velocity (from 14.7 to 12.3 cm/s, p linear regression identified early diastolic mitral annular velocity before ASD closure and age as independent predictors of BNP levels after ASD closure (p annular velocity developed exertional dyspnea after the procedure. In conclusion, our results indicate that TDI measurements could be useful to detect underlying diastolic dysfunction that can potentially cause heart failure after ASD closure and emphasize the importance of ASD closure at a young age before impairment of left ventricular relaxation.

  13. Comparative study of nanocomposites prepared by pulsed and dc sputtering combined with plasma polymerization suitable for photovoltaic device applications

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Amreen A. [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam (India); Pal, Arup R., E-mail: arpal@iasst.gov.in [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam (India); Kar, Rajib [Laser and Plasma Technology Division, Bhabha Atomic Research Center, Trombay, Mumbai (India); Bailung, Heremba; Chutia, Joyanti [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam (India); Patil, Dinkar S. [Laser and Plasma Technology Division, Bhabha Atomic Research Center, Trombay, Mumbai (India)

    2014-12-15

    Plasma processing, a single step method for production of large area composite films, is employed to deposit plasma polymerized aniline-Titanium dioxide (PPani-TiO{sub 2}) nanocomposite thin films. The deposition of PPani-TiO{sub 2} nanocomposite films are made using reactive magnetron sputtering and plasma polymerization combined process. This study focuses on the direct comparison between continuous and pulsed dc magnetron sputtering techniques of titanium in combination with rf plasma polymerization of aniline. The deposited PPani-TiO{sub 2} nanocomposite films are characterized and discussed in terms of structural, morphological and optical properties. A self powered hybrid photodetector has been developed by plasma based process. The proposed method provides a new route where the self-assembly of molecules, that is, the spontaneous association of atomic or molecular building blocks under plasma environment, emerge as a successful strategy to form well-defined structural and morphological units of nanometer dimensions. - Highlights: • PPani-TiO{sub 2} nanocomposite by pulsed and dc sputtering with rf plasma polymerization. • In-situ and Ex-situ H{sub 2}SO{sub 4} doping in PPani-TiO{sub 2} nanocomposite. • PPani-TiO{sub 2} nanocomposite based self-powered-hybrid photodetector.

  14. Enhancement of open-circuit voltage on organic photovoltaic devices by Al-doped TiO{sub 2} modifying layer produced by sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Valaski, R.; Arantes, C.; Senna, C.A.; Carôzo, Victor; Achete, C.A. [Materials Metrology Division, Instituto Nacional de Metrologia, Qualidade e Tecnologia, Xerém, Duque de Caxias 25250-020, RJ (Brazil); Cremona, M., E-mail: cremona@fis.puc-rio.br [Materials Metrology Division, Instituto Nacional de Metrologia, Qualidade e Tecnologia, Xerém, Duque de Caxias 25250-020, RJ (Brazil); Physics Department, Pontifícia Universidade Católica do Rio de Janeiro, Rio de Janeiro 22453-970, RJ (Brazil)

    2014-12-01

    Sol–gel method has shown several advantages for oxide synthesis, such as lower cost production, coating large areas, lower processing temperatures and ease insertion of doping materials. Therefore, it is attractive for production of intermediate and electrode modifying layers in organic optoelectronic devices. Herein, spin-coated aluminum-doped titanium dioxide (AlTiO{sub 2}) thin films were produced by sol–gel method onto glass and fluorine-doped tin oxide (FTO) substrates, using different Al-dopant concentrations and post-done annealing temperatures. Electrical measurements were performed in order to investigate the improvement of the TiO{sub 2} resistivity. Additionally, structural, compositional, morphological, optical and electrical properties of the optimal AlTiO{sub 2} modifying layers onto FTO substrates were probed by different techniques, and compared with those obtained from the undoped thin films produced under similar conditions. Organic photovoltaic devices (OPVs) with the structure FTO/AlTiO{sub 2}(30 nm)/C{sub 60}(50 nm)/CuPc(50 nm)/Al with an Al concentration of 0.03 M in AlTiO{sub 2} layer were produced. The insertion of AlTiO{sub 2} thin films improved the short-circuit current density (J{sub sc}) as well as the open circuit voltage (V{sub oc}) in comparison with non-modified electrode FTO based devices. This behavior is discussed in terms of induced interface phenomena as dipole formation induced by Al. - Highlights: • Easy and cheap solution-process for AlTiO{sub 2} modification of FTO electrode for OPVs • Electrical, structural and optical characterization of TiO{sub 2} layers with Al-dopant • Improvement of Voc and Jsc of inverted OPVs with AlTiO{sub 2} modified electrode.

  15. Influence of surgical implantation angle of left ventricular assist device outflow graft and management of aortic valve opening on the risk of stroke in heart failure patients

    Science.gov (United States)

    Chivukula, V. Keshav; McGah, Patrick; Prisco, Anthony; Beckman, Jennifer; Mokadam, Nanush; Mahr, Claudius; Aliseda, Alberto

    2016-11-01

    Flow in the aortic vasculature may impact stroke risk in patients with left ventricular assist devices (LVAD) due to severely altered hemodynamics. Patient-specific 3D models of the aortic arch and great vessels were created with an LVAD outflow graft at 45, 60 and 90° from centerline of the ascending aorta, in order to understand the effect of surgical placement on hemodynamics and thrombotic risk. Intermittent aortic valve opening (once every five cardiac cycles) was simulated and the impact of this residual native output investigated for the potential to wash out stagnant flow in the aortic root region. Unsteady CFD simulations with patient-specific boundary conditions were performed. Particle tracking for 10 cardiac cycles was used to determine platelet residence times and shear stress histories. Thrombosis risk was assessed by a combination of Eulerian and Lagrangian metrics and a newly developed thrombogenic potential metric. Results show a strong influence of LVAD outflow graft angle on hemodynamics in the ascending aorta and consequently on stroke risk, with a highly positive impact of aortic valve opening, even at low frequencies. Optimization of LVAD implantation and management strategies based on patient-specific simulations to minimize stroke risk will be presented

  16. Development of a high dynamic range spectroscopic system for observation of neutral hydrogen atom density distribution in Large Helical Device core plasma

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, K., E-mail: fujii@me.kyoto-u.ac.jp; Atsumi, S.; Watanabe, S.; Shikama, T.; Hasuo, M. [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 606-8540 (Japan); Goto, M.; Morita, S. [National Institute for Fusion Science, Toki 509-5292 (Japan)

    2014-02-15

    We report development of a high dynamic range spectroscopic system comprising a spectrometer with 30% throughput and a camera with a low-noise fast-readout complementary metal-oxide semiconductor sensor. The system achieves a 10{sup 6} dynamic range (∼20 bit resolution) and an instrumental function approximated by a Voigt profile with Gauss and Lorentz widths of 31 and 0.31 pm, respectively, for 656 nm light. The application of the system for line profile observations of the Balmer-α emissions from high temperature plasmas generated in the Large Helical Device is also presented. In the observed line profiles, emissions are detected in far wings more than 1.0 nm away from the line center, equivalent to neutral hydrogen atom kinetic energies above 1 keV. We evaluate atom density distributions in the core plasma by analyzing the line profiles.

  17. Subcutaneous adipose tissue topography (SAT-Top) by means of the optical device lipometer highly correlated to plasma leptin levels in obese boys

    Science.gov (United States)

    Sudi, Karl; Moeller, Reinhard; Tafeit, Erwin; Reiterer, Elke; Borkenstein, Martin; Vrecko, Karoline; Horejsi, Renate; Reibnegger, Gilbert; Hofmann, Peter

    1998-05-01

    The product of the ob-gene named leptin is correlated with body fat mass in humans. Little evidence exists if the same holds true for body fat distribution. In this study we therefore investigated plasma leptin levels and the subcutaneous adipose tissue topography (SAT-Top) by means of the newly developed optical device Lipometer before and after a 3 week weight reduction camp. Thirty four obese boys (mean age 12a) took part in this study. Body fat distribution were assessed by means of Lipometer to measure the thickness of a subcutaneous fat layer at 15 standardized body sites (SAT- Top). Plasma leptin levels (LL) were measured by radioimmunoassay. All measurements were taken at the beginning and at the end of the camp. By dividing all boys according chronological age (group A: age less than 12a, n equals 17/group B: greater than 12a, n equals 17) we found correlations with the combination of measured body sites (MBS) before (A: MBS vs. LL, R2 equals 0.79; p less than 0.01/B: MBS vs. LL, R2 equals 0.35; n.s.) and after (A: MBS vs. LL, R2 equals 0.83; p less than 0.01/B: MBS vs. LL, R2 equals 0.70; p less than 0.01) the intervention. Our study confirms that the subcutaneous adipose tissue topography (SAT- Top) by means of the optical device Lipometer serves as a marker of plasma leptin levels in obese boys and highlights the use of this optical device in a predictive manner.

  18. Study of the effect of pyrex and quartz insulators on X-ray intensity in a 4 kJ plasma focus device

    Science.gov (United States)

    Koohestani, Saeedeh; Habibi, Morteza; Amrollahi, Reza

    2013-06-01

    In this paper we study the soft X-ray (SXR) and hard X-ray (HXR) intensity produced in different insulator sleeves by a 4 kJ plasma focus device (APF) using filtered PIN-diodes and a fast scintillation detector. The experiments were performed for a great number of neon filling gas pressures at voltages of 11, 12 and 13 kV. Lengths of 40 and 50 mm look optimal to yield the most SXR intensity for the Pyrex and Quartz insulators respectively. The device appears to optimize much better for Pyrex insulator than the Quartz. For Pyrex and Quartz insulators, the lengths of 40 mm and 50 mm seem optimal to yield maximum HXR intensity, respectively.

  19. Power flow between a plasma-opening switch and a load separated by a high-inductance magnetically insulated transmission line

    Science.gov (United States)

    Swanekamp, S. B.; Grossmann, J. M.; Ottinger, P. F.; Commisso, R. J.; Goyer, J. R.

    1994-09-01

    Results are presented from particle-in-cell simulations of the electron flow launched from a plasma opening switch (POS) into a magnetically insulated transmission line (MITL) as the POS opens. The opening process of the POS is treated by removing plasma from a fixed anode-cathode gap with an opening time of tau(sub rise). To be similar to opening switch experiments at Physics International, the simulations were performed with the same inductance L(sub MITL) between the POS and load. When L(sub MITL)/tau(sub rise) is large compared to the POS flow impedance, this inductance effectively isolates the POS from the load during the opening process and the POS voltage is insensitive to changes in the load impedance. Analysis and simulations show that the peak load power is maximized when the load impedance is equal to the POS flow impedance. In contrast to previous theories and simulations of magnetically insulated flows, a large amount of electron flow in the MITL is concentrated near the anode. This is a result of the high effective impedance imposed on the POS by the inductive load which causes a significant electron current loss in the POS. As a result, many electrons lose insulation on the load side of the POS gap and those that do flow into the MITL have been accelerated to nearly the full POS potential. Electrons then E cross B drift on equipotential lines close to the anode as they enter the MITL and flow toward the load. Current losses in the MITL are observed due to the proximity of the electron flow to the anode. Some electrons flow from the MITL directly into the load and are registered as load current while others E cross B drift back toward the POS along the cathode surface. This is possible because the electron flow launched into the MITL from the POS is large enough to cause sufficient positive image charges on the cathode so that the electric field points out of the cathode surface.

  20. Application of NiMoNb adhesion layer on plasma-treated polyimide substrate for flexible electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Bang, S.-H.; Kim, K.-K.; Jung, H.-Y.; Kim, T.-H.; Jeon, S.-H. [Metal and Material Technology Group, R and D Center, LS Mtron Ltd., Gyeonggi 431-080 (Korea, Republic of); Seol, Jae-Bok, E-mail: zptkfm20@hanmail.net [Max-Planck-Insititut für Eisenforschung, Max-Planck-Str. 1, D-40237 Düsseldorf (Germany)

    2014-05-02

    A thin film, NiMoNb, was introduced as an adhesion layer between the Cu metal and the insulator polyimide substrate in a flexible Cu-clad laminated structure. Using 90° peel test, we evaluated the peel strength of the system as a function of the thickness of the adhesion layer. An increase in the NiMoNb thickness from 7 to 40 nm enhanced the peel strength of the deposited systems. After plasma treatment by the roll-to-roll method, the multilayer structure showed an outstanding peel strength of ∼ 529 N/m, even after thermal annealing at 150 °C for 168 h. We also studied the role of plasma treatment of the polyimide substrate on the adhesion strength and microstructure of a flexible Cu-clad laminated structure by peel strength, atomic force microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. These experimental observations showed that the plasma-treated polyimide substrate with the deposition of NiMoNb showed the enhanced adhesion of ∼ 656 N/m, because of the change of functional groups, which affected the bonding force and crystallinity of the thin films deposited on polyimide, rather than an increase in the surface roughness. - Highlights: • NiMoNb film on polyimide substrate was employed for higher peel strength. • Plasma-treated substrate enhances the peel strength of multilayer. • Even when annealed at 150 °C, plasma-treated films showed enhanced peel strength.

  1. Systemic Inflammatory Response Syndrome in End-Stage Heart Failure Patients Following Continuous-Flow Left Ventricular Assist Device Implantation: Differences in Plasma Redox Status and Leukocyte Activation.

    Science.gov (United States)

    Mondal, Nandan K; Sorensen, Erik N; Pham, Si M; Koenig, Steven C; Griffith, Bartley P; Slaughter, Mark S; Wu, Zhongjun J

    2016-05-01

    The role of oxidative stress and leukocyte activation has not been elucidated in developing systemic inflammatory response syndrome (SIRS) in heart failure (HF) patients after continuous-flow left ventricular assist device (CF-LVAD) implantation. The objective of this study was to investigate the change of plasma redox status and leukocyte activation in CF-LVAD implanted HF patients with or without SIRS. We recruited 31 CF-LVAD implanted HF patients (16 SIRS and 15 non-SIRS) and 11 healthy volunteers as the control. Pre- and postimplant blood samples were collected from the HF patients. Plasma levels of oxidized low-density lipoprotein (oxLDL), malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD) in erythrocyte, myeloperoxidase (MPO), and polymorphonuclear elastase (PMN-elastase) were measured. The HF patients had a preexisting condition of oxidative stress than healthy controls as evident from the higher oxLDL and MDA levels as well as depleted SOD and TAC. Leukocyte activation in terms of higher plasma MPO and PMN-elastase was also prominent in HF patients than controls. Persistent oxidative stress and reduced antioxidant status were found to be more belligerent in HF patients with SIRS after the implantation of CF-LVAD when compared with non-SIRS patients. Similar to oxidative stress, the activation of blood leukocyte was significantly highlighted in SIRS patients after implantation compared with non-SIRS. We identified that the plasma redox status and leukocyte activation became more prominent in CF-LVAD implanted HF patients who developed SIRS. Our findings suggest that plasma biomarkers of oxidative stress and leukocyte activation may be associated with the development of SIRS after CF-LVAD implant surgery.

  2. On non-equilibrium atmospheric pressure plasma jets and plasma bullet

    Science.gov (United States)

    Lu, Xinpei

    2012-10-01

    Because of the enhanced plasma chemistry, atmospheric pressure nonequilibrium plasmas (APNPs) have been widely studied for several emerging applications such as biomedical applications. For the biomedical applications, plasma jet devices, which generate plasma in open space (surrounding air) rather than in confined discharge gaps only, have lots of advantages over the traditional dielectric barrier discharge (DBD) devices. For example, it can be used for root canal disinfection, which can't be realized by the traditional plasma device. On the other hand, currently, the working gases of most of the plasma jet devices are noble gases or the mixtures of the noble gases with small amount of O2, or air. If ambient air is used as the working gas, several serious difficulties are encountered in the plasma generation process. Amongst these are high gas temperatures and disrupting instabilities. In this presentation, firstly, a brief review of the different cold plasma jets developed to date is presented. Secondly, several different plasma jet devices developed in our lab are reported. The effects of various parameters on the plasma jets are discussed. Finally, one of the most interesting phenomena of APNP-Js, the plasma bullet is discussed and its behavior is described. References: [1] X. Lu, M. Laroussi, V. Puech, Plasma Sources Sci. Technol. 21, 034005 (2012); [2] Y. Xian, X. Lu, S. Wu, P. Chu, and Y. Pan, Appl. Phys. Lett. 100, 123702 (2012); [3] X. Pei, X. Lu, J. Liu, D. Liu, Y. Yang, K. Ostrikov, P. Chu, and Y. Pan, J. Phys. D 45, 165205 (2012).

  3. Development of Localized Plasma Etching System for Failure Analyses in Semiconductor Devices: (3)Etching-Monitoring Using Quadrupole Mass Spectrometry

    Science.gov (United States)

    Takahashi, Satoshi; Horie, Tomoyuki; Shirayama, Yuya; Yokosuka, Shuntaro; Kashimura, Kenta; Hayashi, Akihiro; Iwase, Chikatsu; Shimbori, Shun'ichiro; Tokumoto, Hiroshi; Naitoh, Yasuhisa; Shimizu, Tetsuo

    Quadrupole mass spectrometry (QMS) has been applied to monitor the etching processes in a localized plasma etching system. An inward plasma was employed for etching in which the etching gas was discharged in the narrow gap between the etched sample and the entrance of an evacuating capillary tube. As the etching products are immediately evacuated through the capillary, a QMS system equipped at the capillary exit is able to analyze the products without any loss in concentration via diffusion into the chamber. Two kinds of samples, thermally grown SiO2 on Si and spin-coated polyimide film on Si, were etched, and the chemical species in the evacuated etching gas were analyzed with QMS, which enables monitoring of the composition of the surface being etched. Samples of thermal SiO2 were etched with CF4 plasma. The peak height of the SiF3+ signal during the SiO2 etching was lower than that observed during etching of the silicon substrate, leading to endpoint detection. The endpoint detection of the polyimide film etching was conducted using two etching gases: pure O2 and pure CF4. When O2 was used, the endpoint was detected by the decrease of the mass peak attributed to CO. When CF4 was employed, the plasma was able to etch both the polyimide film and Si substrate. Then the endpoint was detected by the increase of the mass peak of SiF3+ produced by the etching of the Si substrate.

  4. Platelet-rich plasma preparation using three devices : Implications for platelet activation and platelet growth factor release

    NARCIS (Netherlands)

    Everts, Peter A. M.; Mahoney, Christine Brown; Hoffmann, Johannes J. M. L.; Schonberger, Jacques P. A. M.; Box, Henk A. M.; Van Zundert, Andre; Knape, Johannes T. A.

    2006-01-01

    Background: In this study, three commercial systems for the preparation of platelet-rich plasma (PRP) were compared and platelet growth factors release was measured. Methods: Ten healthy volunteers donated whole blood that was fractionated by a blood cell separator, and a table-top centrifuge to pre

  5. Work function tuning of plasma-enhanced atomic layer deposited WC{sub x}N{sub y} electrodes for metal/oxide/semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Zonensain, Oren; Fadida, Sivan; Eizenberg, Moshe [Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Fisher, Ilanit; Gao, Juwen; Chattopadhyay, Kaushik; Harm, Greg; Mountsier, Tom; Danek, Michal [Lam Research Corporation, 4000 N. First Street, San Jose, California 95134 (United States)

    2015-02-23

    One of the main challenges facing the integration of metals as gate electrodes in advanced MOS devices is control over the Fermi level position at the metal/dielectric interface. In this study, we demonstrate the ability to tune the effective work function (EWF) of W-based electrodes by process modifications of the atomic layer deposited (ALD) films. Tungsten carbo-nitrides (WC{sub x}N{sub y}) films were deposited via plasma-enhanced and/or thermal ALD processes using organometallic precursors. The process modifications enabled us to control the stoichiometry of the WC{sub x}N{sub y} films. Deposition in hydrogen plasma (without nitrogen based reactant) resulted in a stoichiometry of WC{sub 0.4} with primarily W-C chemical bonding, as determined by x-ray photoelectron spectroscopy. These films yielded a relatively low EWF of 4.2 ± 0.1 eV. The introduction of nitrogen based reactant to the plasma or the thermal ALD deposition resulted in a stoichiometry of WC{sub 0.1}N{sub 0.6–0.8} with predominantly W-N chemical bonding. These films produced a high EWF of 4.7 ± 0.1 eV.

  6. Dynamics of three-dimensional radiative structures during RMP assisted detached plasmas on the large helical device and its comparison with EMC3-EIRENE modeling

    Science.gov (United States)

    Pandya, Shwetang N.; Peterson, Byron J.; Kobayashi, Masahiro; Ida, Katsumi; Mukai, Kiyofumi; Sano, Ryuichi; Miyazawa, Junichi; Tanaka, Hirohiko; Masuzaki, Suguru; Akiyama, Tsuyoshi; Motojima, Gen; Ohno, Noriyasu; LHD Experiment Group

    2016-04-01

    The resonant magnetic perturbation (RMP) island introduced in the stochastic edge of the large helical device (LHD) plasma plays an important role in the stabilization of the plasma detachment (Kobayashi et al 2013 Nucl. Fusion 53 093032). The plasma enters in the sustained detachment phase in the presence of an RMP once the line averaged density exceeds a critical value with a given input power. During detachment the enhanced radiation from the stochastic edge of the LHD undergoes several spatiotemporal changes which are studied quantitatively by an infrared imaging video bolometer (IRVB) diagnostic. The experimental results are compared qualitatively and quantitatively with the radiation predicted by the 3D transport simulation with fluid model, EMC3-EIRENE. A fair amount of qualitative agreement, before and after the detachment, is reported. The issue of overestimated radiation from the model is addressed by changing the free parameters in the EMC3-EIRENE code till the total radiation and the radiation profiles match closely, within a factor of two with the experimental observations. A better quantitative match between the model and the experiment is achieved at higher cross-field impurity diffusion coefficient and lower sputtering coefficient after the detachment. In this article a comparison, the first of its kind, is established between the quantified radiation from the experiments and the synthetic image obtained from the simulation code. This exercise is aimed towards validating the model assumptions against the experimentally measured radiation.

  7. Are open-fit hearing aids a possible alternative to bone-anchored hearing devices in patients with mild to severe hearing loss? A preliminary trial

    Directory of Open Access Journals (Sweden)

    Amberley V. Ostevik

    2013-08-01

    Full Text Available Open-fit hearing aids (OFHAs may be of benefit for some individuals with chronic outer and middle ear conditions for which boneanchored hearing devices (BAHDs are normally recommended. The purpose of this study was to compare performance between OFHAs and BAHDs. A Starkey Destiny 800 OFHA was fit on eight adult BAHD users and speech perception measures in quiet and in background noise were compared under two different test conditions: i BAHD only and ii OFHA only. Equivalent outcome measure performance between these two conditions suggests that the OFHA was able to provide sufficient amplification for mild to moderate degrees of hearing loss (pure-tone averages (PTAs less than 47 dB HL. The improved speech perception performances and increased loudness ratings observed for several of the participants with moderately-severe to severe degrees of hearing loss (PTAs of 47 dB HL or greater in the BAHD only condition suggest that the OFHA did not provide sufficient amplification for these individuals. Therefore, OFHAs may be a successful alternative to the BAHD for individuals with no more than a moderate conductive hearing loss who are unable or unwilling to undergo implant surgery or unable to wear conventional hearing aids due to allergies, irritation, or chronic infection associated with the ear being blocked with a shell or earmold.

  8. Three-axis acoustic device for levitation of droplets in an open gas stream and its application to examine sulfur dioxide absorption by water droplets.

    Science.gov (United States)

    Stephens, Terrance L; Budwig, Ralph S

    2007-01-01

    Two acoustic devices to stabilize a droplet in an open gas stream (single-axis and three-axis levitators) have been designed and tested. The gas stream was provided by a jet apparatus with a 64 mm exit diameter and a uniform velocity profile. The acoustic source used was a Langevin vibrator with a concave reflector. The single-axis levitator relied primarily on the radial force from the acoustic field and was shown to be limited because of significant droplet wandering. The three-axis levitator relied on a combination of the axial and radial forces. The three-axis levitator was applied to examine droplet deformation and circulation and to investigate the uptake of SO(2) from the gas stream to the droplet. Droplets ranging in diameters from 2 to 5 mm were levitated in gas streams with velocities up to 9 ms. Droplet wandering was on the order of a half droplet diameter for a 3 mm diameter droplet. Droplet circulation ranged from the predicted Hadamard-Rybczynski pattern to a rotating droplet pattern. Droplet pH over a central volume of the droplet was measured by planar laser induced fluorescence. The results for the decay of droplet pH versus time are in general agreement with published theory and experiments.

  9. Adhesion of Pseudomonas aeruginosa strains to untreated and oxygen-plasma treated poly(vinyl chloride) (PVC) from endotracheal intubation devices.

    Science.gov (United States)

    Triandafillu, K; Balazs, D J; Aronsson, B-O; Descouts, P; Tu Quoc, P; van Delden, C; Mathieu, H J; Harms, H

    2003-04-01

    Pseudomonas aeruginosa pneumonia is a life threatening complication in mechanically ventilated patients that requires the ability of the bacteria to adhere to, and colonize the endotracheal intubation device. New strategies to prevent or reduce these nosocomial infections are greatly needed. We report here the study of a set of P. aeruginosa clinical isolates, together with specific mutants, regarding their adhesion on native and chemically modified poly(vinyl chloride) (PVC) surfaces from endotracheal intubation devices. The adhesion of the different strains to untreated PVC varied widely, correlating with several physico-chemical characteristics known to influence the attachment of bacteria to inert surfaces. The adhesion patterns were compared to the calculations obtained with the DLVO theory of colloidal stability. These results illustrate the importance of testing different clinical isolates when investigating bacterial adhesion. Oxygen plasma treatment of the PVC pieces yielded a hydrophilic surface and reduced the number of adhering bacteria by as much as 70%. This reduction is however unlikely to be sufficient to prevent P. aeruginosa colonization of endotracheal intubation devices.

  10. Comparison of open surgical discectomy versus plasma-laser nucleoplasty in patients with single lumbar disc herniation

    Directory of Open Access Journals (Sweden)

    Saeid Abrishamkar

    2015-01-01

    Full Text Available Background: Intervertebral disc herniation is a major cause of low back pain. Several treatment methods are available for lumbar disc herniation including Chemonucleolysis, open surgery, nucleoplasty, laser disc decompression, and intradiscal electrothermal therapy. The high prevalence of lumbar disc herniation necessitates a minimally invasive yet effective treatment method. In this study, we compared the outcomes of open surgery and nucleoplasty method in patients with single lumbar disc herniation. Materials and Methods: This study was a noninferiority randomized clinical trial conducted in one of the University Hospitals of Isfahan Medical University; The Alzahra Hospital. About 200 patients with the diagnosis of lumbar disc herniation were recruited and were assigned to either the treatment or control groups using block randomization. One group received open surgery and the other group received nucleoplasty as the method of treatment. Patients were revisited at 14 days, 1, 2, 3 months, and 1-year after surgery and were assessed for the following variables: Lower back pain, lower limb pain, common complications of surgery (e.g., discitis, infection and hematoma and recurrence of herniation. Results: The mean (standard deviation severity of low back pain was reduced from 6.92 (2.5 to 3.43 (2.3 in the nucleoplasty group (P = 0.04 and from 7.5 (2.2 to 3.04 (1.61 in the discectomy group (P = 0.73. Between group difference was not statistically significant (P = 0.44, however, time and treatment interaction was significant (P = 0.001. The level of radicular pain evaluated 1 year after treatment was reduced from 8.1 (1.2 to 2.9 (1.2 (P = 0.004 and from 7.89 (2.1 to 3.6 (2.5 (P =0.04 in the discectomy and the nucleoplasty groups respectively, significant interaction between time and treatment options was observed (P < 0.001 while there was no significant difference between two treatment groups (P = 0.82. Conclusion: Our results show that while

  11. Application of atmospheric solution precursor plasma spray to photocatalytic devices for small and medium industries in developing countries

    Science.gov (United States)

    Kindole, Dickson; Ando, Yasutaka

    2017-01-01

    For development of a functional film deposition process with high deposition rate, as a basic study, TiO2 films were deposited by atmospheric solution precursor plasma spray (ASPPS) process. Ethanol-diluted titanium tetraisobutoxide [TTIB: Ti(OC4H9)4] was used as a feedstock. To achieve a high plasma thermal energy at a low discharge power, N2-dominant Ar/N2 as the plasma working gas was used, for film deposition at various deposition distances. Consequently, photocatalytic TiO2 with a rutile/anatase mixture film structure was deposited evenly in this case. By conducting methylene blue decomposition and wettability tests, photocatalytic properties of the film were confirmed. When a TiO2 film was applied to photocatalytic dye-sensitized solar cells (DSSCs), the cells generated an electromotive force of 0.143V oc, which is close to those of commercial DSSCs. From these results, the ASPPS process was found to have high potential for high rate functional film deposition and was cost effective, making it suitable for developing countries.

  12. Simulation of Open-loop Plasma Vertical Movement Response in Damavand Tokamak Using Closed-loop Subspace System Identification

    CERN Document Server

    Farahania, N Darestani

    2015-01-01

    A formulation of a multi-input single-output closed-loop subspace system identification method is employed for the purpose of obtaining control-relevant model of the vacuum-plasma response in Damavand tokamak. Such a model is particularly well suited for robust controller design. The accuracy of the estimate of the plant dynamics is estimated by different experiments. The method described in this paper is a worst-case identification technique, in that it aims to minimize the error between the identified model and the true plant. The identified model fitness around defined operating point is more than 90% and with comparison by physical-based model it has better root mean square measure of the goodness of the fit.

  13. Hard X-ray dose intensity and spatial distribution in a plasma focus device using thermoluminescence dosimeters

    Indian Academy of Sciences (India)

    A Kanani; M N Nasrabadi; B Shirani; I Jabbari

    2015-07-01

    In the present study, X-ray emission dose characteristics from a small Mather-type PF device in various pressures of argon as the operating gas were studied. The PF device was powered by a 12 F capacitor at 25 kV charging voltage. Time-integrated hard X-ray (HXR) emission was investigated using thermoluminescence dosimeters (TLDs). These detectors were calibrated with 60Co and 131Cs sources. Twenty-four dosimeters were placed at four different radial distances from the axis of the electrodes at the top of the anode to measure the dose spatial distribution at the top of the anode for different pressures (0.5–1.3 mbar). At each radius, six dosimeters were placed circularly with equal angular intervals on the inner surface of the device chamber. It was found that the optimum pressure for the highest yield of X-ray is 0.9 mbar. The maximum measured dose was 17 mGy per shot at the top of the anode and about 0.5 mGy per shot at 90° with respect to the anode axis. Furthermore, these results showed that the dose at each radius is symmetrical at 360° around the top of the anode, but X-ray distribution follows an anisotropical behaviour. A fast plastic scintillator was also used for time-resolved HXR detection, and a linear relation was observed between the amplitude of the scintillator-PMT signals and TLD responses.

  14. Characterisation of Plasma Filled Rod Pinch electron beam diode operation

    Science.gov (United States)

    MacDonald, James; Bland, Simon; Chittenden, Jeremy

    2016-10-01

    The plasma filled rod pinch diode (aka PFRP) offers a small radiographic spot size and a high brightness source. It operates in a very similar to plasma opening switches and dense plasma focus devices - with a plasma prefill, supplied via a number of simple coaxial plasma guns, being snowploughed along a thin rod cathode, before detaching at the end. The aim of this study is to model the PFRP and understand the factors that affect its performance, potentially improving future output. Given the dependence on the PFRP on the prefill, we are making detailed measurements of the density (1015-1018 cm-3), velocity, ionisation and temperature of the plasma emitted from a plasma gun/set of plasma guns. This will then be used to provide initial conditions to the Gorgon 3D MHD code, and the dynamics of the entire rod pinch process studied.

  15. Cross-field motion of plasma blob-filaments and related particle flux in an open magnetic field line configuration on QUEST

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.Q., E-mail: hqliu@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 8168580 (Japan); Hanada, K. [Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 8168580 (Japan); Nishino, N. [Graduate School of Engineering, Hiroshima University, Hiroshima 7398511 (Japan); Ogata, R.; Ishiguro, M. [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 8168580 (Japan); Gao, X. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Zushi, H.; Nakamura, K.; Fujisawa, A.; Idei, H.; Hasegawa, M. [Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 8168580 (Japan)

    2013-07-15

    Blob-filaments have been observed by combined measurement with a fast camera and a movable Langmuir probe in an open magnetic field line configuration of electron cyclotron resonance (ECR) heating plasma in QUEST. Blob-filaments extended along field lines do correspond to over-dense plasma structures and propagated across the field lines to the outer wall. The radial velocity of the blob structure, V{sub b}, was obtained by three methods and was dominantly driven by the E × B force. The radial velocity, size of the blob showed good agreements with the results obtained by sheath-connected interchange theoretical model. V{sub b} corresponds to roughly 0.02–0.07 of the local sound speed (C{sub s}) in QUEST. The higher moments (skewness S and kurtosis K) representing the shape of PDF of density fluctuation are studied. Their least squares fitting with quadratic polynomial is K = (1.60 ± 0.27)S{sup 2} − (0.46 ± 0.20). The larger blob structures, occurring only 10% of the time, can carry more than 60% loss of the entire radial particle flux.

  16. Whole exome sequencing implicates eye development, the unfolded protein response and plasma membrane homeostasis in primary open-angle glaucoma

    Science.gov (United States)

    Souzeau, Emmanuelle; Sharma, Shiwani; Landers, John; Mills, Richard; Goldberg, Ivan; Healey, Paul R.; Graham, Stuart; Hewitt, Alex W.; Mackey, David A.; Galanopoulos, Anna; Casson, Robert J.; Ruddle, Jonathan B.; Ellis, Jonathan; Leo, Paul; Brown, Matthew A.; MacGregor, Stuart; Lynn, David J.; Burdon, Kathryn P.; Craig, Jamie E.

    2017-01-01

    Purpose To identify biological processes associated with POAG and its subtypes, high-tension (HTG) and normal-tension glaucoma (NTG), by analyzing rare potentially damaging genetic variants. Methods A total of 122 and 65 unrelated HTG and NTG participants, respectively, with early onset advanced POAG, 103 non-glaucoma controls and 993 unscreened ethnicity-matched controls were included in this study. Study participants without myocilin disease-causing variants and non-glaucoma controls were subjected to whole exome sequencing on an Illumina HiSeq2000. Exomes of participants were sequenced on an Illumina HiSeq2000. Qualifying variants were rare in the general population (MAF < 0.001) and potentially functionally damaging (nonsense, frameshift, splice or predicted pathogenic using SIFT or Polyphen2 software). Genes showing enrichment of qualifying variants in cases were selected for pathway and network analysis using InnateDB. Results POAG cases showed enrichment of rare variants in camera-type eye development genes (p = 1.40×10–7, corrected p = 3.28×10–4). Implicated eye development genes were related to neuronal or retinal development. HTG cases were significantly enriched for key regulators in the unfolded protein response (UPR) (p = 7.72×10–5, corrected p = 0.013). The UPR is known to be involved in myocilin-related glaucoma; our results suggest the UPR has a role in non-myocilin causes of HTG. NTG cases showed enrichment in ion channel transport processes (p = 1.05×10–4, corrected p = 0.027) including calcium, chloride and phospholipid transporters involved in plasma membrane homeostasis. Network analysis also revealed enrichment of the MHC Class I antigen presentation pathway in HTG, and the EGFR1 and cell-cycle pathways in both HTG and NTG. Conclusion This study suggests that mutations in eye development genes are enriched in POAG. HTG can result from aberrant responses to protein misfolding which may be amenable to molecular chaperone therapy. NTG

  17. Plasma Antenna

    OpenAIRE

    N M Vijay

    2014-01-01

    The fundamental base of plasma antenna is the use of an ionized medium as a conductor. The plasma antenna is a radiofrequency antenna formed by a plasma columns, Filaments or sheets, which are excited by a surface wave. The relevance of this device is how rapidly it can be turned on and off, only applying an electrical pulse. Besides its wide carrier frequency, the great directivity and controllable antenna shape. Otherwise a disadvantage is that it needs energy to be ionized....

  18. Sterilization/disinfection of medical devices using plasma: the flowing afterglow of the reduced-pressure N2-O2 discharge as the inactivating medium

    Science.gov (United States)

    Moisan, Michel; Boudam, Karim; Carignan, Denis; Kéroack, Danielle; Levif, Pierre; Barbeau, Jean; Séguin, Jacynthe; Kutasi, Kinga; Elmoualij, Benaïssa; Thellin, Olivier; Zorzi, Willy

    2013-07-01

    Potential sterilization/disinfection of medical devices (MDs) is investigated using a specific plasma process developed at the Université de Montréal over the last decade. The inactivating medium of the microorganisms is the flowing afterglow of a reduced-pressure N2-O2 discharge, which provides, as the main biocidal agent, photons over a broad ultraviolet (UV) wavelength range. The flowing afterglow is considered less damaging to MDs than the discharge itself. Working at gas pressures in the 400—700 Pa range (a few torr) ensures, through species diffusion, the uniform filling of large volume chambers with the species outflowing from the discharge, possibly allowing batch processing within them. As a rule, bacterial endospores are used as bio-indicators (BI) to validate sterilization processes. Under the present operating conditions, Bacillus atrophaeus is found to be the most resistant one and is therefore utilized as BI. The current paper reviews the main experimental results concerning the operation and characterization of this sterilizer/disinfector, updating and completing some of our previously published papers. It uses modeling results as guidelines, which are particularly useful when the corresponding experimental data are not (yet) available, hopefully leading to more insight into this plasma afterglow system. The species flowing out of the N2-O2 discharge can be divided into two groups, depending on the time elapsed after they left the discharge zone as they move toward the chamber, namely the early afterglow and the late afterglow. The early flowing afterglow from a pure N2 discharge (also called pink afterglow) is known to be comprised of N2+ and N4+ ions. In the present N2-O2 mixture discharge, NO+ ions are additionally generated, with a lifetime that extends over a longer period than that of the nitrogen molecular ions. We shall suppose that the disappearance of the NO+ ions marks the end of the early afterglow regime, thereby stressing our intent

  19. Probing the Energy Level Alignment and the Correlation with Open-Circuit Voltage in Solution-Processed Polymeric Bulk Heterojunction Photovoltaic Devices.

    Science.gov (United States)

    Yang, Qing-Dan; Li, Ho-Wa; Cheng, Yuanhang; Guan, Zhiqiang; Liu, Taili; Ng, Tsz-Wai; Lee, Chun-Sing; Tsang, Sai-Wing

    2016-03-23

    Energy level alignment at the organic donor and acceptor interface is a key to determine the photovoltaic performance in organic solar cells, but direct probing of such energy alignment is still challenging especially for solution-processed bulk heterojunction (BHJ) thin films. Here we report a systematic investigation on probing the energy level alignment with different approaches in five commonly used polymer:[6,6]-phenyl-C71-butyric acid methyl ester (PCBM) BHJ systems. We find that by tuning the weight ratio of polymer to PCBM the electronic features from both polymer and PCBM can be obtained by photoemission spectroscopy. Using this approach, we find that some of the BHJ blends simply follow vacuum level alignment, but others show strong energy level shifting as a result of Fermi level pinning. Independently, by measuring the temperature-dependent open-circuit voltage (VOC), we find that the effective energy gap (Eeff), the energy difference between the highest occupied molecular orbital of the polymer donor (EHOMO-D) and lowest unoccupied molecular orbital of the PCBM acceptor (ELUMO-A), obtained by photoemission spectroscopy in all polymer:PCBM blends has an excellent agreement with the extrapolated VOC at 0 K. Consequently, the photovoltage loss of various organic BHJ photovoltaic devices at room temperature is in a range of 0.3-0.6 V. It is believed that the demonstrated direct measurement approach of the energy level alignment in solution-processed organic BHJ will bring deeper insight into the origin of the VOC and the corresponding photovoltage loss mechanism in organic photovoltaic cells.

  20. Method for plasma formation for extreme ultraviolet lithography-theta pinch

    Science.gov (United States)

    Hassanein, Ahmed; Konkashbaev, Isak; Rice, Bryan

    2007-02-20

    A device and method for generating extremely short-wave ultraviolet electromagnetic wave, utilizing a theta pinch plasma generator to produce electromagnetic radiation in the range of 10 to 20 nm. The device comprises an axially aligned open-ended pinch chamber defining a plasma zone adapted to contain a plasma generating gas within the plasma zone; a means for generating a magnetic field radially outward of the open-ended pinch chamber to produce a discharge plasma from the plasma generating gas, thereby producing a electromagnetic wave in the extreme ultraviolet range; a collecting means in optical communication with the pinch chamber to collect the electromagnetic radiation; and focusing means in optical communication with the collecting means to concentrate the electromagnetic radiation.

  1. A Comparison of Proximal Tibia and Proximal Humerus Infusion Rates of Plasma Under High Pressure Using the EZ IO Intraosseous Device in the Adult Swine (Sus scrofa) Hypovolemic Model

    Science.gov (United States)

    2013-01-10

    plasma under high pressure using the EZ IO intraosseous device in the adult swine (Sus scrofa ) hypovolemic model. FWH20100171A FWH20100171ALairet...resuscitation, swine, sus scrofa U U U SAR Vikhyat Bebarta, MD 210-275-3794 WHASC- Animal Final Report 170ct2012 1. Protocol Number: FWH20100171A 2...the EZ 10 intraosseous device in the adult swine (Sus scrofa ) hypovolemic model. 4. Principal Investigator PI): Name Rank Date of Branch Staff

  2. A novel technique based on a plasma focus device for nano-porous gallium nitride formation on P-type silicon

    Science.gov (United States)

    Sharifi Malvajerdi, S.; Salar Elahi, A.; Habibi, M.

    2017-04-01

    A new deposition formation was observed with a Mather-type Plasma Focus Device (MPFD). MPFD was unitized to fabricate porous Gallium Nitride (GaN) on p-type Silicon (Si) substrate with a (100) crystal orientation for the first time in a deposition process. GaN was deposited on Si with 4 and 7 shots. The samples were subjected to a 3 phase annealing procedure. First, the semiconductors were annealed in the PFD with nitrogen plasma shots after their deposition. Second, a thermal chemical vapor deposition annealed the samples for 1 h at 1050 °C by nitrogen gas at a pressure of 1 Pa. Finally, an electric furnace annealed the samples for 1 h at 1150 °C with continuous flow of nitrogen. Porous GaN structures were observed by Field emission scanning electron microscopy and atomic force microscopy. Furthermore, X-Ray diffraction analysis was carried out to determine the crystallinity of GaN after the samples were annealed. Energy-Dispersive X-Ray Spectroscopy indicated the amount of gallium, nitrogen, and oxygen due to the self-oxidation of the samples. Photoluminescence spectroscopy revealed emissions at 2.94 eV and 3.39 eV, which shows that hexagonal wurtzite crystal structures were formed.

  3. Investigation of Device Performance and Negative Bias Temperature Instability of Plasma Nitrided Oxide in Nanoscale p-Channel Metal-Oxide-Semiconductor Field-Effect Transistor's

    Science.gov (United States)

    Han, In-Shik; Ji, Hee-Hwan; Goo, Tae-Gyu; Yoo, Ook-Sang; Choi, Won-Ho; Na, Min-Ki; Kim, Yong-Goo; Park, Sung-Hyung; Lee, Heui-Seung; Kang, Young-Seok; Kim, Dae-Byung; Lee, Hi-Deok

    2008-04-01

    In this paper, we investigated the device performance and negative bias temperature instability (NBTI) degradation for thermally nitrided oxide (TNO) and plasma nitrided oxide (PNO) in nanoscale p-channel metal oxide semiconductor field effect transistor (PMOSFET). PNOs show the improvement of dielectric performance compared to TNO with no change of the device performance. PNOs also show the improvement of NBTI immunity than TNO at low temperature stress, whereas NBTI immunity of PNO with high N concentration can be worse than TNO at high temperature stress. Recovery effect of NBTI degradation of PNO is lower than that of TNO and it is increased as the N concentration is increased in PNO because the dissociated Si dangling bonds and generated positive oxide charges are repassivated and neutralized, respectively. Moreover, complete recovery of ΔVth is dominated by neutralization of positive oxide charges. Therefore, N contents at polycrystalline Si/SiO2 interface as well as N contents at Si/SiO2 interface can affect significantly on NBTI degradation and recovery effect.

  4. 21 CFR 866.2160 - Coagulase plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Coagulase plasma. 866.2160 Section 866.2160 Food... DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2160 Coagulase plasma. (a) Identification. Coagulase plasma is a device that consists of freeze-dried animal or human plasma that is...

  5. Ferroelectric opening switches for large-scale pulsed power drivers.

    Energy Technology Data Exchange (ETDEWEB)

    Brennecka, Geoffrey L.; Rudys, Joseph Matthew; Reed, Kim Warren; Pena, Gary Edward; Tuttle, Bruce Andrew; Glover, Steven Frank

    2009-11-01

    Fast electrical energy storage or Voltage-Driven Technology (VDT) has dominated fast, high-voltage pulsed power systems for the past six decades. Fast magnetic energy storage or Current-Driven Technology (CDT) is characterized by 10,000 X higher energy density than VDT and has a great number of other substantial advantages, but it has all but been neglected for all of these decades. The uniform explanation for neglect of CDT technology is invariably that the industry has never been able to make an effective opening switch, which is essential for the use of CDT. Most approaches to opening switches have involved plasma of one sort or another. On a large scale, gaseous plasmas have been used as a conductor to bridge the switch electrodes that provides an opening function when the current wave front propagates through to the output end of the plasma and fully magnetizes the plasma - this is called a Plasma Opening Switch (POS). Opening can be triggered in a POS using a magnetic field to push the plasma out of the A-K gap - this is called a Magnetically Controlled Plasma Opening Switch (MCPOS). On a small scale, depletion of electron plasmas in semiconductor devices is used to affect opening switch behavior, but these devices are relatively low voltage and low current compared to the hundreds of kilo-volts and tens of kilo-amperes of interest to pulsed power. This work is an investigation into an entirely new approach to opening switch technology that utilizes new materials in new ways. The new materials are Ferroelectrics and using them as an opening switch is a stark contrast to their traditional applications in optics and transducer applications. Emphasis is on use of high performance ferroelectrics with the objective of developing an opening switch that would be suitable for large scale pulsed power applications. Over the course of exploring this new ground, we have discovered new behaviors and properties of these materials that were here to fore unknown. Some of

  6. Open Brief

    Directory of Open Access Journals (Sweden)

    Andrew Leach

    2013-11-01

    Full Text Available To commence the thirtieth annual conference of the Society of Architectural Historians, Australia and New Zealand (SAHANZ, held on Australia’s Gold Coast in July 2013, ten delegates were invited with very little warning to take five minutes and one image to offer a provocation on the open matters of architectural history in the present moment. The term “open” was taken as the conference theme—a device used by SAHANZ meetings not so much to define the scope of papers presented as to declare the conference flavour year by year. It was not, therefore, an open conference (anything goes so much as a conference on open issues (where, indeed, to go.  The ten interlocutors were invited after the conference to document their interventions and they are presented here as a record of the preoccupations of a specific moment and institutional geography with all the idiosyncrasies and commonalities it might reveal to a broader audience.

  7. Effect of deposition parameters on structural and mechanical properties of niobium nitride synthesized by plasma focus device

    Science.gov (United States)

    Siddiqui, Jamil; Hussain, Tousif; Ahmad, Riaz; Khalid, Nida

    2015-06-01

    Effects of deposition angle and axial distance on the structural and mechanical properties of niobium nitride synthesized by a dense plasma focus (DPF) system are studied. The x-ray diffraction (XRD) confirms that the deposition parameters affect the growth of multi-phase niobium nitride. Scanning electron microscopy (SEM) shows the granular surface morphology with strong thermally assisted coagulation effects observed at the 5-cm axial distance. The non-porous granular morphology observed at the 9-cm distance along the anode axis is different from those observed at deposition angles of 10° and 20°. Energy dispersive x-ray (EDX) spectroscopy reveals the maximum nitrogen content at the shortest (5 cm) axial position. Atomic force microscopy (AFM) exhibits that the roughness of coated films varies for coatings synthesized at different axial and angular positions, and the Vickers micro-hardness test shows that a maximum hardness value is (08.44 ± 0.01) GPa for niobium nitride synthesized at 5-cm axial distance, which is about 500% more than that of a virgin sample. Project supported by the HEC, Pakistan.

  8. OpenGL Insights

    CERN Document Server

    Cozzi, Patrick

    2012-01-01

    Get Real-World Insight from Experienced Professionals in the OpenGL Community With OpenGL, OpenGL ES, and WebGL, real-time rendering is becoming available everywhere, from AAA games to mobile phones to web pages. Assembling contributions from experienced developers, vendors, researchers, and educators, OpenGL Insights presents real-world techniques for intermediate and advanced OpenGL, OpenGL ES, and WebGL developers. Go Beyond the Basics The book thoroughly covers a range of topics, including OpenGL 4.2 and recent extensions. It explains how to optimize for mobile devices, explores the design

  9. Special issue on transient plasmas

    Science.gov (United States)

    Bailey, James; Hoarty, David; Mancini, Roberto; Yoneda, Hitoki

    2015-11-01

    This special issue of Journal of Physics B: Atomic, Molecular and Optical Physics is dedicated to the "spectroscopy of transient plasmas" covering plasma conditions produced by a range of pulsed laboratory sources including short and long pulse lasers, pulsed power devices, and free electron lasers (FELs). The full range of plasma spectroscopy up to high energy bremsstrahlung radiation, including line broadening analysis for application to data recorded with the ChemCam instrument on the Mars Science Laboratory rover Curiosity, is covered. This issue is timely as advances in optical lasers and x-ray FELs (XFEL) are enabling transient plasma to be probed at higher energies and shorter durations than ever before. New XFEL facilities being commissioned in Europe and Asia are adding to those operating in the US and Japan and the ELI high power laser project in Europe, due to open this year, will provide short pulse lasers of unprecedented power. This special issue represents a snapshot of the theoretical and experimental research in dense plasmas, electron kinetics, laser-induced breakdown spectroscopy of low temperature plasmas, inertial confinement fusion and non-equilibrium atomic physics using spectroscopy to diagnose plasmas produced by optical lasers, XFELs and pulsed-power machines.

  10. A clinical and histological report of a tooth with an open apex treated with regenerative endodontics using platelet-rich plasma.

    Science.gov (United States)

    Torabinejad, Mahmoud; Faras, Hadi

    2012-06-01

    In patients, the outcomes of teeth with necrotic pulps and open apexes that have been treated with regenerative endodontics have always been evaluated clinically and radiographically. The purpose of this case report is to present the clinical, radiographic, and histological findings of a regenerative procedure using platelet-rich plasma (PRP) 14 months after the procedure. A 12-year-old boy whose maxillary second premolar tooth had been treated with regenerative endodontics was seen with a chief complaint of pain and sensitivity to cold. After clinical and radiographic examinations, a pulpal diagnosis of reversible pulpitis and normal periapical tissues was made for this tooth. Because of the patient's complaint and his guardian's insistence on either a root canal treatment or an extraction, a root canal treatment was performed in this tooth. After entry into the root canal, the soft tissue present in the canal was removed with the aid of a large barbed broach and examined histologically. Examination of the tissue removed from the root canal of this tooth revealed the presence of a vital pulp-like vital connective tissue. There was no evidence of bone in the specimen. Very few inflammatory cells were noted in the periphery of the specimen. Based on these findings, it appears that pulp-like tissue can be generated in a human tooth with the use of PRP as a scaffold in regenerative endodontic procedures. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. Present and Future of Semiconductor Pulsed Power Generator ˜Role of Power Semiconductor Devices in Plasma Research˜ 6.High-Speed, Large-Current Power Semiconductors for Pulse Power Generation

    Science.gov (United States)

    Takata, Ikunori

    This paper describes the operation principles and limits of power semiconductors. In addition, operation mechanisms of the new pulse power devices, SOS (Semiconductor Opening Switch) and dynistors, are explained qualitatively. The fastest operating power device is the series connection of comparatively low-voltage devices. For large-current operation, a uniformly operating pin-diode structure device is essential. An SOS is constructed from dozens of medium voltage (about 3kV) special hard-recovery diodes. This can shut off 2kA current at 10kV with in 10ns. The dynistor has n+pnp+ four layers and two electrodes. Serial-connected dynistors have the potential to replace thyratrons. These new devices can endure over 10 kA/cm2 at much higher voltage than their static breakdown values in the repetitive use more than 1011 times.

  12. Water saving at the field scale with Irrig-OH, an open-hardware environment device for soil water potential monitoring and irrigation management

    Science.gov (United States)

    Masseroni, Daniele; Facchi, Arianna; Gandolfi, Claudio

    2015-04-01

    Sustainability of irrigation practices is an important objective which should be pursued in many countries, especially in areas where water scarcity causes strong conflicts among the different water uses. The efficient use of water is a key factor in coping with the food demand of an increasing world population and with the negative effects of the climate change on water resources availability in many areas. In this complex context, it is important that farmers adopt instruments and practices that enable a better management of water at the field scale, whatever the irrigation method they adopt. This work presents the hardware structure and the functioning of an open-hardware microstation based on the Arduino technology, called Irrig-OH, which allows the continuous and low-cost monitoring of the soil water potential (SWP) in the root zone for supporting the irrigation scheduling at the field scale. In order to test the microstation, an experiment was carried out during the agricultural season 2014 at Lodi (Italy), with the purpose of comparing the farmers' traditional management of irrigation of a peach variety and the scheduling based on the SWP measurements provided by the microstation. Additional measurements of leaf water potential (LWP), stomatal resistance, transpiration (T), crop water stress index (CWSI) and fruit size evolution were performed respectively on leafs and fruits for verifying the plant physiological responses on different SWP levels in soil. At the harvesting time, the peach production in term of quantity and quality (sucrose content was measured by a rifractometer over a sample of one hundred fruits) of the two rows were compared. Irrigation criteria was changed with respect to three macro-periods: up to the endocarp hardening phase (begin of May) soil was kept well watered fixing the SWP threshold in the first 35 cm of the soil profile at -20 kPa, during the pit hardening period (about the entire month of May) the allowed SWP threshold was

  13. Measurement of ion beam angular distribution at different helium gas pressures in a plasma focus device by large-area polycarbonate detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sohrabi, M.; Habibi, M., E-mail: mortezahabibi@gmail.com; Ramezani, V. [Amirkabir University of Technology, Energy Engineering and Physics Department (Iran, Islamic Republic of)

    2017-02-15

    The paper presents an experimental study and analysis of full helium ion density angular distributions in a 4-kJ plasma focus device (PFD) at pressures of 10, 15, 25, and 30 mbar using large-area polycarbonate track detectors (PCTDs) (15-cm etchable diameter) processed by 50-Hz-HV electrochemical etching (ECE). Helium ion track distributions at different pressures, in particular, at the main axis of the PFD are presented. Maximum ion track density of ~4.4 × 10{sup 4} tracks/cm{sup 2} was obtained in the PCTD placed 6 cm from the anode. The ion distributions for all pressures applied are ring-shaped, which is possibly due to the hollow cylindrical copper anode used. The large-area PCTD processed by ECE proves, at the present state-of-theart, a superior method for direct observation and analysis of ion distributions at a glance with minimum efforts and time. Some observations of the ion density distributions at different pressures are reported and discussed.

  14. Metal imaging on surface of micro- and nanoelectronic devices by laser ablation inductively coupled plasma mass spectrometry and possibility to measure at nanometer range.

    Science.gov (United States)

    Zoriy, Myroslav V; Mayer, Dirk; Becker, J Sabine

    2009-05-01

    An analytical mass spectrometric method for the elemental analysis of nano-bioelectronic devices involved in bioengineering research was developed and applied for measurements of selected metals (Au, Ti, Pt, Cr, etc.) on interdigitated electrode array chips (IDA-chip). An imaging laser ablation inductively coupled plasma mass spectrometric (LA-ICP-MS) procedure was used to map the elements of interest on the surface of the analyzed sample. The obtained images of metals were in a good agreement and corresponded to the micro- and nanofabricated metal electrode pattern. For the analysis at nanometer resolution scale a NF-LA-ICP-MS (NF-near-field) procedure was applied, which utilize thin Ag needle to enhance laser beam energy and improve spatial resolution of the method. The results show a approximately 100x enhancement of analyte signal, when the needle was positioned in the "near-field region" to the sample surface and the laser shot was performed. In addition, mass spectrometric studies of reproducibly for five separated NF-LA shots in different places of analyzed sample yielded an RSD of the measurement of 16%.

  15. Early effects comparison of X-rays delivered at high-dose-rate pulses by a plasma focus device and at low dose rate on human tumour cells.

    Science.gov (United States)

    Virelli, A; Zironi, I; Pasi, F; Ceccolini, E; Nano, R; Facoetti, A; Gavoçi, E; Fiore, M R; Rocchi, F; Mostacci, D; Cucchi, G; Castellani, G; Sumini, M; Orecchia, R

    2015-09-01

    A comparative study has been performed on the effects of high-dose-rate (DR) X-ray beams produced by a plasma focus device (PFMA-3), to exploit its potential medical applications (e.g. radiotherapy), and low-DR X-ray beams produced by a conventional source (XRT). Experiments have been performed at 0.5 and 2 Gy doses on a human glioblastoma cell line (T98G). Cell proliferation rate and potassium outward currents (IK) have been investigated by time lapse imaging and patch clamp recordings. The results showed that PFMA-3 irradiation has a greater capability to reduce the proliferation rate activity with respect to XRT, while it does not affect IK of T98G cells at any of the dose levels tested. XRT irradiation significantly reduces the mean IK amplitude of T98G cells only at 0.5 Gy. This work confirms that the DR, and therefore the source of radiation, is crucial for the planning and optimisation of radiotherapy applications.

  16. Dioxin-like and perfluorinated compounds in pigs in an Indian open waste dumping site: toxicokinetics and effects on hepatic cytochrome P450 and blood plasma hormones.

    Science.gov (United States)

    Watanabe, Michio X; Kunisue, Tatsuya; Tao, Lin; Kannan, Kurunthachalam; Subramanian, Annamalai; Tanabe, Shinsuke; Iwata, Hisato

    2010-07-01

    Dioxins and related compounds (DRCs) and perfluorinated compounds were measured in the livers of pigs (Sus scrofa) collected from an open waste dumping site in South India. Hepatic concentrations of DRCs and perfluorooctanesulfonate (PFOS; up to 200 ng/g wet wt) were significantly higher in male and female pigs, respectively, collected from the dumping site than in those from a reference site. Results suggest that dumping sites are a source of DRCs and PFOS. Hepatic concentrations of DRCs in piglets were higher than in mothers, especially for the congeners with molecular weights in the range of 360 to 400, implying congener-specific maternal transfer of DRCs in swine. Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans and some non-ortho dioxin-like polychlorinated biphenyls (PCBs) in the liver of pigs were higher than those in the adipose fat and muscle of the same specimens. In addition, the liver-to-adipose concentration ratios for each congener had a significant positive correlation with the levels of hepatic cytochrome P450 (CYP)1A-like protein, suggesting congener-specific and CYP1A-dependent hepatic sequestration of DRCs in the swine. Total hepatic 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs; 8.9-350 pg/g fat wt) had a significant positive correlation with CYP1A-like protein expression (r=0.56, p=0.012), suggesting the induction of CYP1A by DRCs. However, the total TEQs had a significant negative correlation with CYP4A-like protein (r=-0.49, p=0.029), suggesting repression of peroxisome proliferator-activated receptor-alpha (PPARalpha)-mediated signaling pathway by DRCs. Decreases in plasma total thyroxine (T4), free T4, and immunoglobulin (Ig) G were also found in pigs from the dumping site compared with those from the reference site. This study provides insight into the toxicological impacts of DRCs and perfluorinated compounds in wild animals from open waste dumping sites.

  17. Method validation for high resolution sector field inductively coupled plasma mass spectrometry determination of the emerging contaminants in the open ocean: Rare earth elements as a case study

    Science.gov (United States)

    Wysocka, Irena; Vassileva, Emilia

    2017-02-01

    Analytical procedure for the determination of fourteen rare earth elements (REEs) in the seawater samples has been developed and validated. The elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) at ultra-trace level were measured by high resolution sector field inductively coupled plasma mass spectrometry (HR ICP-SFMS) after off-line analytes pre-concentration and matrix separation. The sample pre-treatment was carried out by commercially available automated system seaFAST-pico™, which is a low-pressure ion chromatography technique, based on solid phase extraction principles. Efficient elimination of seawater matrix and up to 50-fold pre-concentration of REEs enabled their accurate and precise quantification at ng L- 1 level. A validation approach in line with the requirements of ISO/IEC 17025 standard and Eurachem guidelines were followed. With this in mind, selectivity, working range, linearity, recovery (from 92% to 102%), repeatability (1%-4%), intermediate precision (2%-6%), limits of detection (0.001-0.08 ng L- 1) were systematically assessed. The total uncertainty associated to each result was estimated and the main sources of uncertainty sorted out. All major contributions to the combined uncertainty of the obtained results were identified and propagated together, following the ISO/GUM guidelines. The relative expanded uncertainty was estimated at range from 10.4% to 11.6% (k = 2). Demonstration of traceability of measurement results was also presented. Due to the low limits of detection, this method enables the determination of ultra-low levels of REEs in the open seawater as well as small variations in their concentrations. The potential of the proposed analytical procedure, based on combination of seaFAST-pico™ for sample preparation and HR ICP-SFMS, was demonstrated by direct analysis of seawater form different regions of the world.

  18. Open cycle thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Robert Stowers [Georgia Inst. of Technology, Atlanta, GA (United States)

    2000-01-01

    A new type of thermodynamic device combining a thermodynamic cycle with the externally applied steady flow of an open thermodynamic process is discussed and experimentally demonstrated. The gas flowing through this device can be heated or cooled in a series of semi-open cyclic steps. The combination of open and cyclic flows makes possible the elimination of some or all of the heat exchangers (with their associated irreversibility). Heat is directly exchanged with the process fluid as it flows through the device when operating as a refrigerator, producing a staging effect that tends to increase First Law thermodynamic efficiency. An open-flow thermoacoustic refrigerator was built to demonstrate this concept. Several approaches are presented that describe the physical characteristics of this device. Tests have been conducted on this refrigerator with good agreement with a proposed theory.

  19. Open Innovation in Practice: Goal Complementarity and Closed NPD Networks to Explain Differences in Innovation Performance for SMEs in the Medical Devices Sector

    NARCIS (Netherlands)

    Pullen, A.J.J.; de Weerd-Nederhof, Petronella C.; Groen, Arend J.; Fisscher, O.A.M.

    2012-01-01

    Cooperation with other organizations increases the innovation performance of organization, especially for small and medium-sized enterprises (SMEs) as they encounter liabilities of “smallness” (e.g., limited financial resources, and manpower). In the medical devices sector, collaboration with

  20. Open Innovation in Practice: Goal Complementarity and Closed NPD Networks to Explain Differences in Innovation Performance for SMEs in the Medical Devices Sector

    NARCIS (Netherlands)

    Pullen, Annemien J.J.; Weerd-Nederhof, de Petra C.; Groen, Aard J.; Fisscher, Olaf A.M.

    2011-01-01

    Cooperation with other organizations increases the innovation performance of organization, especially for small and medium-sized enterprises (SMEs) as they encounter liabilities of “smallness” (e.g., limited financial resources, and manpower). In the medical devices sector, collaboration with extern

  1. Open Innovation in Practice: Goal Complementarity and Closed NPD Networks to Explain Differences in Innovation Performance for SMEs in the Medical Devices Sector

    NARCIS (Netherlands)

    Pullen, A.J.J.; Weerd-Nederhof, de P.C.; Groen, A.J.; Fisscher, O.A.M.

    2012-01-01

    Cooperation with other organizations increases the innovation performance of organization, especially for small and medium-sized enterprises (SMEs) as they encounter liabilities of “smallness” (e.g., limited financial resources, and manpower). In the medical devices sector, collaboration with extern

  2. Open Innovation in Practice: Goal Complementarity and Closed NPD Networks to Explain Differences in Innovation Performance for SMEs in the Medical Devices Sector

    NARCIS (Netherlands)

    Pullen, A.J.J.; de Weerd-Nederhof, Petronella C.; Groen, Arend J.; Fisscher, O.A.M.

    2012-01-01

    Cooperation with other organizations increases the innovation performance of organization, especially for small and medium-sized enterprises (SMEs) as they encounter liabilities of “smallness” (e.g., limited financial resources, and manpower). In the medical devices sector, collaboration with extern

  3. Pulp revascularization using platelet rich plasma autologous or in conjunction with a collagen matrix as a therapeutic possibility for teeth with an open apex necrotic pulp and / or periapical pathology.

    OpenAIRE

    Camargo Guevara, Paula Alejandra; Sossa Rojas, Henry

    2014-01-01

    Objective: Describe the use of the Autologous Platelet-Rich Plasma or in combination with a collagen matrix as a potential revascularization therapy in teeth with open apices, necrotic pulp and/or periapical lesion. Methods: A thematic literature searchwas conducted from 2007 to 2013 using electronic means,  databases and journals with high impact on endodontic. Results: Regenerative endodontic is a biological based procedure  designed to replace structures that have been damaged, diseased or...

  4. Usability of a novel disposable autoinjector device for ixekizumab: results from a qualitative study and an open-label clinical trial, including patient-reported experience

    Science.gov (United States)

    Callis Duffin, Kristina; Bukhalo, Michael; Bobonich, Margaret A; Shrom, David; Zhao, Fangyi; Kershner, James R; Gill, Anne; Pangallo, Beth; Shuler, Catherine L; Bagel, Jerry

    2016-01-01

    Background Most biologic therapies for psoriasis are delivered via subcutaneous injection. Ixekizumab, an anti-interleukin 17A monoclonal antibody approved for patients with moderate-to-severe plaque psoriasis, is delivered subcutaneously via prefilled syringe or autoinjector. Here we report the results of an ixekizumab autoinjector usability study as well as the patient-reported experience with the autoinjector in a clinical trial. Methods The usability study enrolled 49 subjects (patients with a range of autoimmune conditions or their caregivers). Subjects were randomized to a trained or untrained group and were evaluated for their ability to perform an injection successfully when provided the device and the instructions for use. In the clinical trial, 102 subjects (patients with psoriasis or their caregivers) used the autoinjector to deliver injections of ixekizumab (80 mg every 2 weeks after a starting dose of 160 mg). At weeks 0, 4, and 8, subjects completed the subcutaneous administration assessment questionnaire, which assesses the ease of use and confidence with using an injection device. Results In the usability study, all subjects in the untrained arm performed successful injections, while two subjects in the trained arm had an injection failure. These incidences were not consistent with any pattern of issues with the device or the instructions for use. In the clinical trial, there were two injection failures of 674 total self-injections performed over 12 weeks. At the first use of the device, 95% of subjects either agreed or strongly agreed that the device was “overall easy to use”, and they felt “confident the dose was complete” according to the subcutaneous administration assessment questionnaire. Conclusion The ixekizumab autoinjector was used successfully by patients and caregivers with or without training. Subjects using the autoinjector in a clinical trial felt it was easy to use and felt confident while using it. PMID:27785115

  5. Suppressed ion-scale turbulence in a hot high-β plasma

    Science.gov (United States)

    Schmitz, L.; Fulton, D. P.; Ruskov, E.; Lau, C.; Deng, B. H.; Tajima, T.; Binderbauer, M. W.; Holod, I.; Lin, Z.; Gota, H.; Tuszewski, M.; Dettrick, S. A.; Steinhauer, L. C.

    2016-12-01

    An economic magnetic fusion reactor favours a high ratio of plasma kinetic pressure to magnetic pressure in a well-confined, hot plasma with low thermal losses across the confining magnetic field. Field-reversed configuration (FRC) plasmas are potentially attractive as a reactor concept, achieving high plasma pressure in a simple axisymmetric geometry. Here, we show that FRC plasmas have unique, beneficial microstability properties that differ from typical regimes in toroidal confinement devices. Ion-scale fluctuations are found to be absent or strongly suppressed in the plasma core, mainly due to the large FRC ion orbits, resulting in near-classical thermal ion confinement. In the surrounding boundary layer plasma, ion- and electron-scale turbulence is observed once a critical pressure gradient is exceeded. The critical gradient increases in the presence of sheared plasma flow induced via electrostatic biasing, opening the prospect of active boundary and transport control in view of reactor requirements.

  6. Nonequilibrium plasma generator (NPG) project - experimental program

    Energy Technology Data Exchange (ETDEWEB)

    Lineberry, J.T.; Wu, Y.C.L.; Lin, B.C. [and others

    1995-12-31

    This paper summarizes research conducted under a DOE MHD SBIR entitled: {open_quotes}A Light Metal Fueled Non-equilibrium Plasma Generator (NPG){close_quotes}. It is a summary paper presenting the idea of the NPG and activities of the NPG SBIR research program along with experimental results from NPG Proof-of-Principle tests. The NPG is an innovative concept for a combustion device that can produce a nonequilibrium plasma. This device bums powdered metal fuel, and it can be used to drive an MHD disk generator pulse power unit or a similar nonequilibrium MHD device or system. The NPG research program was concluded over the past two years under sponsorship of a DOE Phase II SBIR grant. This program focused on addressing fundamental and practical aspects of the NPG concept and its system design. The research included investigation of the physics of the NPG concept through theoretical and experimental studies on the quality of the plasma that it can produce, theoretical evaluations of the nonequilibrium ionization processes in an MHD disk generator driven by an NPG, and experimental validation of the NPG concept in Proof-of-Principle tests. At the conclusion of this research it was determined that the NPG is indeed a viable concept. Results from combustion tests using powdered aluminum fuel reveal that the NPG can produce an extremely hot argon plasma clean enough to support nonequilibrium ionization in an MHD device.

  7. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    technological solution in the early to late 1990s of confining atmospheric plasmas in a small volume of plasma generation (i.e. with a small volume-to-surface ratio) and then extending it towards a downstream sample [7]-[9]. These are among the first low-temperature atmospheric plasmas aimed particularly at the exploitation of their ability to invoke the active and rich reactive chemistry close to ambient temperature. The main applications of these early devices are precision surface modification of low-temperature dielectric materials, for example thin film deposition and etching [7]-[9]. Variations of the early plasma jets include atmospheric plasma sheet jets [10] for the treatment of largely planar objects (e.g. polymeric sheets) as well as large arrays of many plasma jets for the treatment of complex-structured objects (e.g. surgical tools and open human wounds) [11]. As a material processing technology, the sub-100oC atmospheric-pressure plasma jet has benefited over the years from many innovations. Whilst a detailed account and analysis of these is clearly outside the scope of this Editorial, it is worth stating that there are different avenues with which to maintain a moderate electron density at the plasma core so as to keep the gas temperature at the sample point below a ceiling level. Most of the early studies employed excitation at radio frequencies above 10 MHz, at which electrons are largely confined in the plasma generation region, and this limits the current flow to and gas heating in the plume region of the plasma jet. Other techniques of current limitation have since been shown to be effective, including the use of dielectric barriers across a very large frequency range of 1 kHz--50 MHz, sub-microsecond pulses sustained at kHz frequencies, pulse-modulated radio frequencies and dual-frequency excitation [12]-[15]. These and other techniques have considerably advanced the atmospheric-pressure plasma jet technology. The period of some 15 years since the above

  8. Usability of a novel disposable autoinjector device for ixekizumab: results from a qualitative study and an open-label clinical trial, including patient-reported experience

    Directory of Open Access Journals (Sweden)

    Callis Duffin K

    2016-10-01

    Full Text Available Kristina Callis Duffin,1 Michael Bukhalo,2 Margaret A Bobonich,3 David Shrom,4 Fangyi Zhao,4 James R Kershner,4 Anne Gill,4 Beth Pangallo,4 Catherine L Shuler,4 Jerry Bagel5 1Department of Dermatology, University of Utah School of Medicine, Salt Lake City, UT, 2Arlington Dermatology, Arlington Heights, IL, 3CWRU Schools of Medicine and Nursing, Case Western Reserve University Cleveland, OH, 4Lilly Research Labs, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, 5Psoriasis Treatment Center of Central New Jersey, East Windsor, NJ, USA Background: Most biologic therapies for psoriasis are delivered via subcutaneous injection. Ixekizumab, an anti-interleukin 17A monoclonal antibody approved for patients with moderate-to-severe plaque psoriasis, is delivered subcutaneously via prefilled syringe or autoinjector. Here we report the results of an ixekizumab autoinjector usability study as well as the patient-reported experience with the autoinjector in a clinical trial. Methods: The usability study enrolled 49 subjects (patients with a range of autoimmune conditions or their caregivers. Subjects were randomized to a trained or untrained group and were evaluated for their ability to perform an injection successfully when provided the device and the instructions for use. In the clinical trial, 102 subjects (patients with psoriasis or their caregivers used the autoinjector to deliver injections of ixekizumab (80 mg every 2 weeks after a starting dose of 160 mg. At weeks 0, 4, and 8, subjects completed the subcutaneous administration assessment questionnaire, which assesses the ease of use and confidence with using an injection device. Results: In the usability study, all subjects in the untrained arm performed successful injections, while two subjects in the trained arm had an injection failure. These incidences were not consistent with any pattern of issues with the device or the instructions for use. In the clinical trial, there were two

  9. Physics of photonic devices

    CERN Document Server

    Chuang, Shun Lien

    2009-01-01

    The most up-to-date book available on the physics of photonic devices This new edition of Physics of Photonic Devices incorporates significant advancements in the field of photonics that have occurred since publication of the first edition (Physics of Optoelectronic Devices). New topics covered include a brief history of the invention of semiconductor lasers, the Lorentz dipole method and metal plasmas, matrix optics, surface plasma waveguides, optical ring resonators, integrated electroabsorption modulator-lasers, and solar cells. It also introduces exciting new fields of research such as:

  10. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  11. A new ICRF scenario for bulk ion heating in D-T plasmas: How to utilize intrinsic impurities in fusion devices in our favour

    CERN Document Server

    Kazakov, Y O; Van Eester, D; Bilato, R; Dumont, R; Lerche, E; Mantsinen, M; Messiaen, A

    2015-01-01

    A fusion reactor requires plasma pre-heating before the rate of deuterium-tritium fusion reactions becomes significant. In ITER, radiofrequency (RF) heating of 3He ions, additionally puffed into the plasma, is one of the main options considered for increasing bulk ion temperature during the ramp-up phase of the pulse. In this paper, we propose an alternative scenario for bulk ion heating with RF waves, which requires no extra 3He puff and profits from the presence of intrinsic Beryllium impurities in the plasma. The discussed method to heat Be impurities in D-T plasmas is shown to provide an even larger fraction of fuel ion heating.

  12. 便携式应急分合闸控制装置的研制及应用%Development and application of portable emergency open-close switch control device

    Institute of Scientific and Technical Information of China (English)

    韩世军; 毛吉贵; 杨国华; 陈一鸣

    2016-01-01

    Aiming at the problem that electromagnetic operating mechanism of 10 kV pole-mounted circuit breaker cannot reliably close switch when Feeder Terminal Unit(FTU)direct current power source disappear or lack capacity, deeply analyzes the causes, develops portable emergency open-close switch control device, applies it into distribution automatic dispatch and distribution equipment maintenance, The application result shows that:portable emergency open-close switch control device can effectively satisfy the requirement of FTU and pole- mounted distribution equipments for uninterruptible power supply(UPS), during power interrupted. The device is safety, reliable, and applied widely and has practical engineering application value.%针对10 kV柱上断路器的电磁操动机构在馈线远程终端(Feeder Terminal Unitm, FTU)直流电源消失或者容量不足时不能可靠合闸的问题,深入分析原因,研制了便携式应急分合闸控制装置,并应用到配电自动化调试及配电设备检修工作中。应用结果表明:便携式应急分合闸控制装置有效地满足了配电网停电检修时FTU及各类柱上配电设备对不间断电源的需求,应用范围广泛,安全可靠,具有一定的工程实用价值。

  13. Effects of the charge-transfer reorganization energy on the open-circuit voltage in small-molecular bilayer organic photovoltaic devices: comparison of the influence of deposition rates of the donor.

    Science.gov (United States)

    Lee, Chih-Chien; Su, Wei-Cheng; Chang, Wen-Chang

    2016-05-14

    The theoretical maximum of open-circuit voltage (VOC) of organic photovoltaic (OPV) devices has yet to be determined, and its origin remains debated. Here, we demonstrate that VOC of small-molecule OPV devices can be improved by controlling the deposition rate of a donor without changing the interfacial energy gap at the donor/acceptor interface. The measurement of external quantum efficiency and electroluminescence spectra facilitates the observation of the existence of charge transfer (CT) states. A simplified approach by reusing the reciprocity relationship for obtaining the properties of the CT states is proposed without introducing complex techniques. We compare experimental and fitting results and propose that reorganization energy is the primary factor in determining VOC instead of either the CT energy or electronic coupling term in bilayer OPV devices. Atomic force microscopy images indicate a weak molecular aggregation when a higher deposition rate is used. The results of temperature-dependent measurements suggest the importance of molecular stacking for the CT properties.

  14. Numerical modelling of electromagnetic loads on fusion device structures

    Science.gov (United States)

    Bettini, Paolo; Furno Palumbo, Maurizio; Specogna, Ruben

    2014-03-01

    In magnetic confinement fusion devices, during abnormal operations (disruptions) the plasma begins to move rapidly towards the vessel wall in a vertical displacement event (VDE), producing plasma current asymmetries, vessel eddy currents and open field line halo currents, each of which can exert potentially damaging forces upon the vessel and in-vessel components. This paper presents a methodology to estimate electromagnetic loads, on three-dimensional conductive structures surrounding the plasma, which arise from the interaction of halo-currents associated to VDEs with a magnetic field of the order of some Tesla needed for plasma confinement. Lorentz forces, calculated by complementary formulations, are used as constraining loads in a linear static structural analysis carried out on a detailed model of the mechanical structures of a representative machine.

  15. EDITORIAL: Stochasticity in fusion plasmas Stochasticity in fusion plasmas

    Science.gov (United States)

    Unterberg, Bernhard

    2010-03-01

    Structure formation and transport in stochastic plasmas is a topic of growing importance in many fields of plasma physics from astrophysics to fusion research. In particular, the possibility to control transport in the boundary of confined fusion plasmas by resonant magnetic perturbations has been investigated extensively during recent years. A major research achievement was finding that the intense transient particle and heat fluxes associated with edge localized modes (here type-I ELMs) in magnetically confined fusion plasmas can be mitigated or even suppressed by resonant magnetic perturbation fields. This observation opened up a possible scheme to avoid too large erosion and material damage by such transients in future fusion devices such as ITER. However, it is widely recognized that a more basic understanding is needed to extrapolate the results obtained in present experiments to future fusion devices. The 4th workshop on Stochasticity in Fusion Plasmas was held in Jülich, Germany, from 2 to 4 March 2009. This series of workshops aims at gathering fusion experts from various plasma configurations such as tokamaks, stellarators and reversed field pinches to exchange knowledge on structure formation and transport in stochastic fusion plasmas. The workshops have attracted colleagues from both experiment and theory and stimulated fruitful discussions about the basics of stochastic fusion plasmas. Important papers from the first three workshops in 2003, 2005 and 2007 have been published in previous special issues of Nuclear Fusion (stacks.iop.org/NF/44/i=6, stacks.iop.org/NF/46/i=4 and stacks.iop.org/NF/48/i=2). This special issue comprises contributions presented at the 4th SFP workshop, dealing with the main subjects such as formation of stochastic magnetic layers, energy and particle transport in stochastic magnetic fields, plasma response to external, non-axis-symmetric perturbations and last but not least application of resonant magnetic perturbations for

  16. Open cycle gas core nuclear rockets

    Science.gov (United States)

    Ragsdale, Robert

    1991-01-01

    The open cycle gas core engine is a nuclear propulsion device. Propulsion is provided by hot hydrogen which is heated directly by thermal radiation from the nuclear fuel. Critical mass is sustained in the uranium plasma in the center. It has typically 30 to 50 kg of fuel. It is a thermal reactor in the sense that fissions are caused by absorption of thermal neutrons. The fast neutrons go out to an external moderator/reflector material and, by collision, slow down to thermal energy levels, and then come back in and cause fission. The hydrogen propellant is stored in a tank. The advantage of the concept is very high specific impulse because you can take the plasma to any temperature desired by increasing the fission level by withdrawing or turning control rods or control drums.

  17. An open cycle gas core fusion rocket for space exploration

    Science.gov (United States)

    Kammash, T.; Godfrey, T.

    A nuclear propulsion system that utilizes fusion reactions to heat a plasma in a magnetically confined device is examined as a potential rocket. It makes use of a high density plasma in a magnetic mirror geometry with a collision mean free path much shorter than its length. Under these conditions the plasma behaves like a fluid with confinement properties dictated by gasdynamic laws. Accordingly, the plasma escape from the device is analogous to the flow of a gas into vacuum from a vessel with a hole. Such a system is capable of producing a very high specific impulse albeit at modest thrust. One approach for enhancing the thrust is to use an auxiliary hydrogen propellant that could be regeneratively heated before it is introduced into the reactor chamber. As is flows past the fusion plasma it will be further heated by the radiation (bremsstrahlung and synchrotron) emanating from the plasma, and upon emergence from the nozzle it will generate the desired thrust. The system thus functions much like an open cycle gas core rocket with very attractive propulsive capabilities. In this paper we present the underlying physics principles of such a concept and assess its capability by applying the results to a round trip mission to Mars. It is shown that the propulsion parameters exceed those of a gas core fission reactor and without many of major hydrodynamic problems confronted by the latter.

  18. Investigation of stability and x-ray spectrum in gas-puff z-pinch plasmas diriven by inductive energy storage pulsed power generator with a plasma opening switch

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, K.; Fukudome, I. [Yatsushiro National College of Technology, Dept. of Mechanical and Electrical Engineering, Yatsushiro, Kumamoto (Japan); Teramoto, Y.; Katsuki, S.; Akiyama, H. [Kumamoto Univ., Dept. of Electrical and Computer Engineering, Kumamoto (Japan)

    2002-06-01

    Gas-puff z-pinch plasmas are driven by an inductive voltage adder - inductive energy storage pulsed power generator ''ASO-X''. ASO-X has the performance of the maximum output voltage and current are 180 kV and 400 kA respectively and can provide a fast rise time current with operating POS. The stability of the plasma column, spectrum radiated from z-pinch plasmas and the spatial distribution of hot spots are investigated in the case with and without operating POS. By driving ASO-X with operating POS the kink instability is restrained and the stability of plasma column is improved about three times in regard to the average dispersion. Furthermore the duration of soft x-ray radiation is increased and the spatial distribution of hot spots is 50% improved with regard to kurtosis of the intensity profile of pinhole photographs compared to those without operating POS. (author)

  19. Increasing the open-circuit voltage in high-performance organic photovoltaic devices through conformational twisting of an indacenodithiophene-based conjugated polymer.

    Science.gov (United States)

    Chen, Chih-Ping; Hsu, Hsiang-Lin

    2013-10-01

    A fused ladder indacenodithiophene (IDT)-based donor-acceptor (D-A)-type alternating conjugated polymer, PIDTHT-BT, presenting n-hexylthiophene conjugated side chains is prepared. By extending the degree of intramolecular repulsion through the conjugated side chain moieties, an energy level for the highest occupied molecular orbital (HOMO) of -5.46 eV--a value approximately 0.27 eV lower than that of its counterpart PIDTDT-BT--is obtained, subsequently providing a fabricated solar cell with a high open-circuit voltage of approximately 0.947 V. The hole mobility (determined using the space charge-limited current model) in a blend film containing 20 wt% PIDTHT-BT) and 80 wt% [6,6]-phenyl-C71 butyric acid methyl ester (PC71 BM) is 2.2 × 10(-9) m(2) V(-1) s(-1), which is within the range of reasonable values for applications in organic photovoltaics. The power conversion efficiency is 4.5% under simulated solar illumination (AM 1.5G, 100 mW cm(-2)).

  20. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    OpenAIRE

    Titus, Monica Joy

    2010-01-01

    The semiconductor industry's continued trend of manufacturing device features on the nanometer scale requires increased plasma processing control and improved understanding of plasma characteristics and plasma-surface interactions. This dissertation presents a series of experimental results for focus studies conducted in an inductively coupled plasma (ICP) system. First novel "on-wafer" diagnostic tools are characterized and related to plasma characteristics. Second, plasma-polymer interactio...

  1. 大尺寸大气压空气等离子体射流设备研究%A Large Scale Air Plasma Jet Device at Atmospheric Pressure

    Institute of Scientific and Technical Information of China (English)

    李森; 吴立; 徐凯; 顾璠

    2015-01-01

    A specially designed device to generate large scale plasma jet at atmospheric pressure is reported. The device is a modified dielectric barrier discharge with a high polymer film as dielectric. It is capable of generating a plasma jet with the diameter up to 28 mm and the length up to several tens mm in the surrounding air. There are various excited plasma species shown through optical emission spectrum. The jet temperature is close to room temperature. Therefore, this device may be used for some applications such as the decontamination of temperature-sensitive materials, surface modification, etc.%本文提出了一种特殊的大尺寸大气压空气等离子体射流设备。该设备采用一种高分子耐高温涂料作为介质进行放电,通过气体渐扩通道,产生大尺寸空气等离子体射流,射流直径最宽处可以达到28 mm,长度可以达到数十mm。本文对射流中的活性物质进行光谱测量,同时对射流宏观温度进行测量,指出该射流温度非常接近室温,可以用于温度敏感材料的表面处理等方面。

  2. A non-equilibrium plasma generator

    Energy Technology Data Exchange (ETDEWEB)

    Lineberry, J.T.; Wu, Y.C.L.; Martin, J.F. [ERC, Incorporated, Tullahoma, TN (United States)

    1993-12-31

    This paper summarizes research ideas, results and activities on a DOE MHD SBIR entitled: {open_quote}A Light Metal Fueled Nonequilibrium Plasma Generator (NPG){close_quotes}. The NPG is a concept for a device that has the capability of producing a nonequilibrium plasma from metal combustion. The results of preliminary studies on the NPG concept are given. These studies address fundamentals of the NPG including operating concepts of the NPG concept, results of studies on the quality of the plasma that it can produce, and theoretical evaluations of the nonequilibrium ionization process in an MHD disk generator driven by an NPG. A discussion of potential applications for the NPG is given. These applications encompass pulse MHD power, commercial MHD power and disk MHD generator research.

  3. Development and Demonstration of a Device to Determine Thrust by Measuring the Force on a Target Plate in the Exhaust of a Plasma Thruster

    Science.gov (United States)

    Chavers, Greg; Chang-Diaz, Franklin

    2004-01-01

    A device has been developed to measure the force on a target plate by an impacting beam of charged and neutral particles. This device, an impact thrust stand, was developed to allow thrusters at low TRL, levels to be easily tested without the expense of developing a flight prototype of the thruster to be placed on a conventional thrust stand. The impact thrust stand was developed for the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) but has been tested and calibrated using several devices including Hall thrusters. The calibration and comparison of the impact thrust stand against conventional thrust stands will be discussed in this paper.

  4. A preliminary report on the efficacy of a dynamic jaw opening device (dynasplint trismus system) as part of the multimodal treatment of trismus in patients with head and neck cancer.

    Science.gov (United States)

    Stubblefield, Michael D; Manfield, Laura; Riedel, Elyn R

    2010-08-01

    To examine the effectiveness of a dynamic jaw opening device as part of a multimodal treatment strategy for trismus in patients with head and neck cancer. Retrospective cohort study. Tertiary care cancer center. Patients with head and neck cancer and trismus (N=20). All patients underwent assessment by a board-certified physiatrist and were referred to physical therapy for delivery of the DTS and instructed to progress use of the DTS to 30 minutes 3 times a day. Additional modalities for the treatment of trismus including pain medications and botulinum toxin injections were prescribed as clinically indicated. Change in maximal interincisal distance (MID) as documented in the medical record. The use of the DTS as part of multimodal therapy including physical therapy, pain medications, and botulinum toxin injections as deemed clinically appropriate resulted in an overall improvement of the MID from 16.5mm to 23.5mm (Ptrismus associated with head and neck cancer and its treatment. Further investigation is needed to determine the relative efficacy of the treatment modalities available for trismus including physical therapy and other jaw stretching devices.

  5. Four-factor prothrombin complex concentrate versus plasma for rapid vitamin K antagonist reversal in patients needing urgent surgical or invasive interventions: a phase 3b, open-label, non-inferiority, randomised trial.

    Science.gov (United States)

    Goldstein, Joshua N; Refaai, Majed A; Milling, Truman J; Lewis, Brandon; Goldberg-Alberts, Robert; Hug, Bruce A; Sarode, Ravi

    2015-05-23

    Rapid reversal of vitamin K antagonist (VKA)-induced anticoagulation is often necessary for patients needing urgent surgical or invasive procedures. The optimum means of VKA reversal has not been established in comparative clinical trials. We compared the efficacy and safety of four-factor prothrombin complex concentrate (4F-PCC) with that of plasma in VKA-treated patients needing urgent surgical or invasive procedures. In a multicentre, open-label, phase 3b randomised trial we enrolled patients aged 18 years or older needing rapid VKA reversal before an urgent surgical or invasive procedure. We randomly assigned patients in a 1:1 ratio to receive vitamin K concomitant with a single dose of either 4F-PCC (Beriplex/Kcentra/Confidex; CSL Behring, Marburg, Germany) or plasma, with dosing based on international normalised ratio (INR) and weight. The primary endpoint was effective haemostasis, and the co-primary endpoint was rapid INR reduction (≤1·3 at 0·5 h after infusion end). The analyses were intended to evaluate, in a hierarchical fashion, first non-inferiority (lower limit 95% CI greater than -10% for group difference) for both endpoints, then superiority (lower limit 95% CI >0%) if non-inferiority was achieved. Adverse events and serious adverse events were reported to days 10 and 45, respectively. This trial is registered at ClinicalTrials.gov, number NCT00803101. 181 patients were randomised (4F-PCC n=90; plasma n=91). The intention-to-treat efficacy population comprised 168 patients (4F-PCC, n=87; plasma, n=81). Effective haemostasis was achieved in 78 (90%) patients in the 4F-PCC group compared with 61 (75%) patients in the plasma group, demonstrating both non-inferiority and superiority of 4F-PCC over plasma (difference 14·3%, 95% CI 2·8-25·8). Rapid INR reduction was achieved in 48 (55%) patients in the 4F-PCC group compared with eight (10%) patients in the plasma group, demonstrating both non-inferiority and superiority of 4F-PCC over plasma

  6. A high-order particle-in-cell method for low density plasma flow and the simulation of gyrotron resonator devices

    Energy Technology Data Exchange (ETDEWEB)

    Stock, Andreas

    2013-04-26

    Within this thesis a parallelized, transient, three-dimensional, high-order discontinuous Galerkin Particle-in-Cell solver is developed and used to simulate the resonant cavity of a gyrotron. The high-order discontinuous Galerkin approach - a Finite-Element type method - provides a fast and efficient algorithm to numerically solve Maxwell's equations used within this thesis. Besides its outstanding dissipation and dispersion properties, the discontinuous Galerkin approach easily allows for using unstructured grids, as required to simulate complex-shaped engineering devices. The discontinuous Galerkin approach approximates a wavelength with significantly less degrees of freedom compared to other methods, e.g. Finite Difference methods. Furthermore, the parallelization capabilities of the discontinuous Galerkin framework are excellent due to the very local dependencies between the elements. These properties are essential for the efficient numerical treatment of the Vlasov-Maxwell system with the Particle-in-Cell method. This system describes the self-consistent interaction of charged particles and the electromagnetic field. As central application within this thesis gyrotron resonators are simulated with the discontinuous Galerkin Particle-in-Cell method on high-performance-computers. The gyrotron is a high-power millimeter wave source, used for the electron cyclotron resonance heating of magnetically confined fusion plasma, e.g. in the Wendelstein 7-X experimental fusion-reactor. Compared to state-of-the-art simulation tools used for the design of gyrotron resonators the Particle-in-Cell method does not use any significant physically simplifications w.r.t. the modelling of the particle-field-interaction, the geometry and the wave-spectrum. Hence, it is the method of choice for validation of current simulation tools being restricted by these simplifications. So far, the Particle-in-Cell method was restricted to be used for demonstration calculations only, because

  7. Electrooptical devices

    Science.gov (United States)

    Hurwitz, C. E.

    1980-03-01

    This report covers work carried out with support of the Department of the Air Force during the period 1 October 1979 through 31 March 1980. A part of this support was provided by the Rome Air Development Center. CW operation at temperatures up to 55 C has been achieved for GaInAsP/InP double-heterostructure (DH) lasers emitting at 1.5 micrometers, which were grown without a GaInAsP buffer layer. These devices are of interest for use as sources in fiber-optics communications systems, since the lowest transmission loss reported for fused-silica optical fibers occurs at 1.55 micrometers. Surface passivation techniques developed for InP and GaInAsP avalanche photodiodes have resulted in reductions of dark current as large as four orders of magnitude, to values as low as .0000016 A/sq cm at 0.9 V(b) where V(b) is the breakdown voltage. Devices consisting entirely of InP have been passivated with plasma-deposited Si3N4, and those with a GaInAsP layer but with the p-n junction in InP have been passivated with polyimide. Neither of these techniques successfully reduces dark currents in devices with the p-n junction in the GaInAsP, but a film of photoresist sprayed with SF6 as the propellant has given excellent results. The electrical characteristics in InP ion implanted with Sn, Ge, Si, and C have been investigated. All of these column IV elements yielded n-type conductivity and Sn, Ge, and Si showed high electrical activation; however, implanted C was found to have a net electrical activation of only about 5 percent.

  8. Direct plasma interaction with living tissue

    Science.gov (United States)

    Fridman, Gregory

    For some time, plasma has been used in medicine to cauterize or cut tissue using heat and mechanical energy. In the recent decade, some researchers around the world have started to investigate how gas jets that pass through thermal plasma can be employed in medicine. This thesis presents the first investigation of biomedical uses of non-thermal plasma discharge which comes in direct contact with living tissue. It is demonstrated that the direct application of non-thermal plasma in air can cause rapid deactivation of bacteria on surfaces of tissues without causing any visible tissue damage. Medical need for such a device is discussed. Construction and operation of various types of non-thermal plasma power supplies and many types of treatment electrodes are presented as well. Application of this plasma to living organisms is shown to be safe from both the electrical perspective and from the biological perspective. Biological safety is revealed through a series of differential skin toxicity trials on human cadaver tissue, live hairless mouse skin tissue, live pig skin tissue, and finally in an open wound model on pigs. Direct non-thermal plasma in air is shown to deactivate bacteria about 100 times faster than indirect application using jets. A series of experiments reveal that this effectiveness is due to the ability of direct discharge to bring charges to tissue surfaces. It is demonstrated that neither ultraviolet (UV) radiation nor neutral active species such as hydroxyl radicals or ozone produced in plasma are responsible for the main effect on bacteria. Although much additional work remains on establishing detailed mechanism by which charges from plasma achieve this effect, the work carried out in this thesis clearly demonstrates that direct application of non-thermal plasma in air can be a very useful tool in medicine.

  9. Plasma medicine—current state of research and medical application

    Science.gov (United States)

    Weltmann, K.-D.; von Woedtke, Th

    2017-01-01

    Plasma medicine means the direct application of cold atmospheric plasma (CAP) on or in the human body for therapeutic purposes. Further, the field interacts strongly with results gained for biological decontamination. Experimental research as well as first practical application is realized using two basic principles of CAP sources: dielectric barrier discharges (DBD) and atmospheric pressure plasma jets (APPJ). Originating from the fundamental insights that the biological effects of CAP are most probably caused by changes of the liquid environment of cells, and are dominated by reactive oxygen and nitrogen species (ROS, RNS), basic mechanisms of biological plasma activity are identified. It was demonstrated that there is no increased risk of cold plasma application and, above all, there are no indications for genotoxic effects. The most important biological effects of cold atmospheric pressure plasma were identified: (1) inactivation of a broad spectrum of microorganisms including multidrug resistant ones; (2) stimulation of cell proliferation and tissue regeneration with lower plasma treatment intensity (treatment time); (3) inactivation of cells by initialization of programmed cell death (apoptosis) with higher plasma treatment intensity (treatment time). In recent years, the main focus of clinical applications was in the field of wound healing and treatment of infective skin diseases. First CAP sources are CE-certified as medical devices now which is the main precondition to start the introduction of plasma medicine into clinical reality. Plasma application in dentistry and, above all, CAP use for cancer treatment are becoming more and more important research fields in plasma medicine. A further in-depth knowledge of control and adaptation of plasma parameters and plasma geometries is needed to obtain suitable and reliable plasma sources for the different therapeutic indications and to open up new fields of medical application.

  10. Enhancement-mode AlGaN/GaN HEMTs fabricated by fluorine plasma treatment

    Institute of Scientific and Technical Information of China (English)

    Quan Si; Hao Yue; Ma Xiaohua; Xie Yuanbin; Ma Jigang

    2009-01-01

    The fabrication of enhancement-mode A1GaN/GaN HEMTs by fluorine plasma treatment on sapphire substrates is reported. A new method is used to fabricate devices with different fluorine plasma RF power treatments on one wafer to avoid differences between different wafers. The plasma-treated gate regions of devices treated with different fluorine plasma RF powers were separately opened by a step-and-repeat system. The properties of these devices are compared and analyzed. The devices with 150 W fluorine plasma treatment power and with 0.6μm gate-length exhibited a threshold voltage of 0.57 V, a maximum drain current of 501 mA/mm, a maximumtransconductance of 210 m S/mm, a current gain cutoff frequency of 19.4 GHz and a maximum oscillation frequency of 26 GHz. An excessive fluorine plasma treatment power of 250 W results in a small maximum drain current, which can be attributed to the implantation of fluorine plasma in the channel.

  11. Reduction of leakage current by O{sub 2} plasma treatment for device isolation of AlGaN/GaN heterojunction field-effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Ying; Wang, Qingpeng [School of Electronic Science and Technology, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Institute of Technology and Science, The University of Tokushima, 2-1 Minami-josanjima, Tokushima 770-8506 (Japan); Zhang, Fuzhe; Li, Liuan [Institute of Technology and Science, The University of Tokushima, 2-1 Minami-josanjima, Tokushima 770-8506 (Japan); Zhou, Deqiu; Liu, Yang [School of Physics and Engineering, Sun Yat-Sen University, 135 Xingang Xi Road, Guangzhou 510275 (China); Wang, Dejun, E-mail: dwang121@dlut.edu.cn [School of Electronic Science and Technology, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Ao, Jin-Ping, E-mail: jpao@ee.tokushima-u.ac.jp [Institute of Technology and Science, The University of Tokushima, 2-1 Minami-josanjima, Tokushima 770-8506 (Japan)

    2015-10-01

    Highlights: • The influence of O{sub 2} plasma treatment on mesa region of AlGaN/GaN HFET was studied. • An effective condition of O{sub 2} plasma treatment was confirmed. • The treated GaN surface was characterized by PL spectrum and XPS. • The AlGaN/GaN HFET with an on/off drain current ratio of 1.73 × 10{sup 7} was achieved. • The breakdown voltage of the mesa-isolated region improved. - Abstract: The influence of O{sub 2} plasma treatment on the mesa-isolated region of AlGaN/GaN heterojunction field-effect transistors (HFETs) was studied. The etched surface of the undoped GaN layer was exposed to O{sub 2} plasma generated by a plasma-enhanced chemical vapor deposition system. The current–voltage characteristics indicated that the current of the mesa-isolated region was strongly dependent on the treatment temperature. Treatment with O{sub 2} plasma at 300 °C and 250 W for 15 min was confirmed to be the optimal condition, under which isolation current was reduced by four orders of magnitude and photovoltaic response was suppressed. The photoluminescence spectrum showed a decrease in the density of defects related to the yellow luminescence band and the occurrence of defects related to the blue luminescence band. X-ray photoelectron spectroscopy results showed the formation of Ga{sub 2}O{sub 3} and a possible defect of substitutional oxygen on the nitrogen site O{sub N}. AlGaN/GaN HFETs with an on/off drain current ratio of 1.73 × 10{sup 7} were obtained, and the breakdown voltage of the mesa-isolated region increased from 171.5 to 467.2 V.

  12. OpenSHS: Open Smart Home Simulator

    Directory of Open Access Journals (Sweden)

    Nasser Alshammari

    2017-05-01

    Full Text Available This paper develops a new hybrid, open-source, cross-platform 3D smart home simulator, OpenSHS, for dataset generation. OpenSHS offers an opportunity for researchers in the field of the Internet of Things (IoT and machine learning to test and evaluate their models. Following a hybrid approach, OpenSHS combines advantages from both interactive and model-based approaches. This approach reduces the time and efforts required to generate simulated smart home datasets. We have designed a replication algorithm for extending and expanding a dataset. A small sample dataset produced, by OpenSHS, can be extended without affecting the logical order of the events. The replication provides a solution for generating large representative smart home datasets. We have built an extensible library of smart devices that facilitates the simulation of current and future smart home environments. Our tool divides the dataset generation process into three distinct phases: first design: the researcher designs the initial virtual environment by building the home, importing smart devices and creating contexts; second, simulation: the participant simulates his/her context-specific events; and third, aggregation: the researcher applies the replication algorithm to generate the final dataset. We conducted a study to assess the ease of use of our tool on the System Usability Scale (SUS.

  13. Penetration of conductive plasma flows across a magnetic field

    Science.gov (United States)

    Plechaty, Christopher Ryan

    2008-02-01

    Plasma interacts with magnetic fields in a variety of natural and laboratory settings. While a magnetic field "traps" isolated charged particles, plasma penetration across magnetic field is observed in many situations where a plasma-magnetic interface exists. For example, in the realm of pulsed power technology, this behavior is important for magnetically insulated transmission lines and for plasma opening switches. In the realm of astrophysics, the nature of the interaction between the solar wind plasma and the Earth's magnetic field affects the reliability of telecommunication devices and satellites. Experiments were performed at the Nevada Terawatt Facility to investigate how a conductive plasma penetrates an externally applied magnetic field. In experiment, a plasma flow was produced by laser ablation. This plasma was observed to penetrate an externally applied magnetic field produced by a 0.6 MA pulsed power generator. In experiment, the duration of the laser pulse was changed by three orders of magnitude, from ns (GW pulse power) to ps (TW) . This resulted in a significant variation of the plasma parameters, which in turn led to the actuation of different magnetic field penetration mechanisms.

  14. A New LxxxA Motif in the Transmembrane Helix3 of Maize Aquaporins Belonging to the Plasma Membrane Intrinsic Protein PIP2 Group Is Required for Their Trafficking to the Plasma Membrane1[W][OPEN

    Science.gov (United States)

    Chevalier, Adrien S.; Bienert, Gerd Patrick; Chaumont, François

    2014-01-01

    Aquaporins play important roles in maintaining plant water status under challenging environments. The regulation of aquaporin density in cell membranes is essential to control transcellular water flows. This work focuses on the maize (Zea mays) plasma membrane intrinsic protein (ZmPIP) aquaporin subfamily, which is divided into two sequence-related groups (ZmPIP1s and ZmPIP2s). When expressed alone in mesophyll protoplasts, ZmPIP2s are efficiently targeted to the plasma membrane, whereas ZmPIP1s are retained in the endoplasmic reticulum (ER). A protein domain-swapping approach was utilized to demonstrate that the transmembrane domain3 (TM3), together with the previously identified N-terminal ER export diacidic motif, account for the differential localization of these proteins. In addition to protoplasts, leaf epidermal cells transiently transformed by biolistic particle delivery were used to confirm and refine these results. By generating artificial proteins consisting of a single transmembrane domain, we demonstrated that the TM3 of ZmPIP1;2 or ZmPIP2;5 discriminates between ER and plasma membrane localization, respectively. More specifically, a new LxxxA motif in the TM3 of ZmPIP2;5, which is highly conserved in plant PIP2s, was shown to regulate its anterograde routing along the secretory pathway, particularly its export from the ER. PMID:24989232

  15. plasma treatment

    Directory of Open Access Journals (Sweden)

    Puač Nevena

    2014-11-01

    Full Text Available In this paper we will present results for plasma sterilization of planktonic samples of two reference strains of bacteria, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. We have used a plasma needle as a source of non-equilibrium atmospheric plasma in all treatments. This device is already well characterized by OES, derivative probes and mass spectrometry. It was shown that power delivered to the plasma is bellow 2 W and that it produces the main radical oxygen and nitrogen species believed to be responsible for the sterilization process. Here we will only present results obtained by electron paramagnetic resonance which was used to detect the OH, H and NO species. Treatment time and power delivered to the plasma were found to have the strongest influence on sterilization. In all cases we have observed a reduction of several orders of magnitude in the concentration of bacteria and for the longest treatment time complete eradication. A more efficient sterilization was achieved in the case of gram negative bacteria.

  16. A randomised open-label cross-over study of inhaler errors, preference and time to achieve correct inhaler use in patients with COPD or asthma: comparison of ELLIPTA with other inhaler devices.

    Science.gov (United States)

    van der Palen, Job; Thomas, Mike; Chrystyn, Henry; Sharma, Raj K; van der Valk, Paul Dlpm; Goosens, Martijn; Wilkinson, Tom; Stonham, Carol; Chauhan, Anoop J; Imber, Varsha; Zhu, Chang-Qing; Svedsater, Henrik; Barnes, Neil C

    2016-11-24

    Errors in the use of different inhalers were investigated in patients naive to the devices under investigation in a multicentre, single-visit, randomised, open-label, cross-over study. Patients with chronic obstructive pulmonary disease (COPD) or asthma were assigned to ELLIPTA vs DISKUS (Accuhaler), metered-dose inhaler (MDI) or Turbuhaler. Patients with COPD were also assigned to ELLIPTA vs Handihaler or Breezhaler. Patients demonstrated inhaler use after reading the patient information leaflet (PIL). A trained investigator assessed critical errors (i.e., those likely to result in the inhalation of significantly reduced, minimal or no medication). If the patient made errors, the investigator demonstrated the correct use of the inhaler, and the patient demonstrated inhaler use again. Fewer COPD patients made critical errors with ELLIPTA after reading the PIL vs: DISKUS, 9/171 (5%) vs 75/171 (44%); MDI, 10/80 (13%) vs 48/80 (60%); Turbuhaler, 8/100 (8%) vs 44/100 (44%); Handihaler, 17/118 (14%) vs 57/118 (48%); Breezhaler, 13/98 (13%) vs 45/98 (46%; all PELLIPTA and did not require investigator instruction. Instruction was required for DISKUS (65%), MDI (85%), Turbuhaler (71%), Handihaler (62%) and Breezhaler (56%). Fewer asthma patients made critical errors with ELLIPTA after reading the PIL vs: DISKUS (3/70 (4%) vs 9/70 (13%), P=0.221); MDI (2/32 (6%) vs 8/32 (25%), P=0.074) and significantly fewer vs Turbuhaler (3/60 (5%) vs 20/60 (33%), PELLIPTA over the other devices (all P⩽0.002). Significantly, fewer COPD patients using ELLIPTA made critical errors after reading the PIL vs other inhalers. More asthma and COPD patients preferred ELLIPTA over comparator inhalers.

  17. Communications for Wearable Devices

    OpenAIRE

    Tabibu, Shivram

    2017-01-01

    Wearable devices are transforming computing and the human-computer interaction and they are a primary means for motion recognition of reflexive systems. We review basic wearable deployments and their open wireless communications. An algorithm that uses accelerometer data to provide a control and communication signal is described. Challenges in the further deployment of wearable device in the field of body area network and biometric verification are discussed.

  18. Plasma polarization spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Iwamae, Atsushi; Inoue, Takeru; Tanaka, Akihiro; Kawakami, Kazuki; Fujimoto, Takashi [Kyoto Univ., Dept. of Engineering Physics, Kyoto (Japan)

    2000-03-01

    Polarization of radiation emitted from plasma reflects the anisotropic properties of the plasma, especially the angular isotropic distribution of electron velocities. Polarization has been observed on impurity ion lines from the WT-3 tokamak and GAMMA 10 tandem mirror device. (author)

  19. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.

    1968-01-01

    The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3......The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3...

  20. Experiments on the transportation of a magnetized plasma stream in the GOL-3 facility

    Science.gov (United States)

    Postupaev, V. V.; Batkin, V. I.; Burdakov, A. V.; Ivanov, I. A.; Kuklin, K. N.; Mekler, K. I.; Rovenskikh, A. F.

    2016-04-01

    The program of the deep upgrade of the GOL-3 multiple-mirror trap is presented. The upgrade is aimed at creating a new GOL-NB open trap located at the GOL-3 site and intended to directly demonstrate the efficiency of using multiple-mirror magnetic cells to improve longitudinal plasma confinement in a gasdynamic open trap. The GOL-NB device will consist of a new central trap, adjoint cells with a multiple-mirror magnetic field, and end tanks (magnetic flux expanders). Plasma in the central trap will be heated by neutral beam injection with a power of up to 1.5 MW and duration of 1 ms. At present, physical experiments directed at developing plasma technologies that are novel for this facility are being carried out using the 6-m-long autonomous part of the GOL-3 solenoid. The aim of this work was to develop a method for filling the central trap with a low-temperature start plasma. Transportation of a plasma stream from an arc source over a distance of 3 m in a uniform magnetic field with an induction of 0.5-4.5 T is demonstrated. In these experiments, the axial plasma density was (1-4) × 1020 m-3 and the mirror ratio varied from 5 to 60. In general, the experiments confirmed the correctness of the adopted decisions for the start plasma source of the GOL-NB device.

  1. Optic chiasm compression from mass effect and thrombus formation following unsuccessful treatment of a giant supraclinoid ICA aneurysm with the Pipeline device: open surgical bailout with STA-MCA bypass and parent vessel occlusion.

    Science.gov (United States)

    Abla, Adib A; Zaidi, Hasan A; Crowley, R Webster; Britz, Gavin W; McDougall, Cameron G; Albuquerque, Felipe C; Spetzler, Robert F

    2014-07-01

    Pipeline Embolization Devices (PEDs) have been shown to be effective for intracranial internal carotid artery (ICA) aneurysms, and are now approved by the FDA specifically for this use. Potential pitfalls, however, have not yet been described in the pediatric neurosurgical literature. The authors report on a 10-year-old boy who presented to the Barrow Neurological Institute after progressive visual decline. He had undergone placement of a total of 7 telescoping PEDs at another facility for a large ICA aneurysm. Residual filling of the aneurysm and significant expansion of intraaneurysmal thrombus with chiasmal compression on admission images were causes for concern. The patient underwent a surgical bailout with a superficial temporal artery-middle cerebral artery bypass, with parent artery occlusion. Postoperative vascular imaging was notable for successful occlusion of the parent vessel, with no evidence of filling of the aneurysm. Reports on the pitfalls of PEDs in the neurosurgical literature are scarce. To the authors' knowledge this represents the first paper describing a successful open surgical bailout for residual aneurysmal filling and expansion of thrombus after placement of a PED.

  2. Advanced simulation technology for etching process design for CMOS device applications

    Science.gov (United States)

    Kuboi, Nobuyuki; Fukasawa, Masanaga; Tatsumi, Tetsuya

    2016-07-01

    Plasma etching is a critical process for the realization of high performance in the next generation of CMOS devices. To predict and control fluctuations in the etching properties accurately during mass production, it is essential that etching process simulation technology considers fluctuations in the plasma chamber wall conditions, the effects of by-products on the critical dimensions, the Si recess dependence on the wafer open area ratio and local pattern structure, and the time-dependent plasma-induced damage distribution associated with the three-dimensional feature scale profile at the 100 nm level. This consideration can overcome the issues with conventional simulations performed under the assumed ideal conditions, which are not accurate enough for practical process design. In this article, these advanced process simulation technologies are reviewed, and, from the results of suitable process simulations, a new etching system that automatically controls the etching properties is proposed to enable stable CMOS device fabrication with high yields.

  3. Final report for the NSF/DOE partnership in basic plasma science grant DE-FG02-06ER54906 'Laser-driven collisionless shocks in the Large Plasma Device'

    Energy Technology Data Exchange (ETDEWEB)

    Niemann, Christoph [UCLA, CA (United States); Gekelman, W. [UCLA, CA (United States); Winske, D. [LANL, NM (United States); Larsen, D. [LLNL, CA (United States)

    2012-12-14

    We have performed several thousand high-energy laser shots in the LAPD to investigate the dynamics of an exploding laser-produced plasma in a large ambient magneto-plasma. Debris-ions expanding at super-Alfvenic velocity (up to MA=1.5) expel the ambient magnetic field, creating a large (> 20 cm) diamagnetic cavity. We observed field compressions of up to B/B{sub 0} = 1.5 at the edge of the bubble, consistent with the MHD jump conditions, as well as localized electron heating at the edge of the bubble. Two-dimensional hybrid simulations reproduce these measurements well and show that the majority of the ambient ions are energized by the magnetic piston to super-Alfvenic speeds and swept outside the bubble volume. Nonlinear shear-Alfven waves ({delta}B/B{sub 0} > 25%) are radiated from the cavity with a coupling efficiency of 70% from magnetic energy in the bubble to the wave. While the data is consistent with a weak magneto-sonic shock, the experiments were severely limited by the low ambient plasma densities (10{sup 12} cm{sup -3}). 2D hybrid simulations indicate that future experiments with the new LAPD plasma source and densities in excess of 10{sup 13} cm{sup -3} will drive full-blown collisionless shocks with MA>10 over several c/wpi and shocked Larmor radii. In a separate experiment at the LANL Trident laser facility we have performed a proof-of-principle experiment at higher densities to demonstrate key elements of collisionless shocks in laser-produced magnetized plasmas with important implications to NIF. Simultaneously we have upgraded the UCLA glass-laser system by adding two large amplitude disk amplifiers from the NOVA laser and boost the on-target energy from 30 J to up to 1 kJ, making this one of the world’s largest university-scale laser systems. We now have the infrastructure in place to perform novel and unique high-impact experiments on collision-less shocks at the LAPD.

  4. Magnetically insulated opening switch research

    Science.gov (United States)

    McGeoch, M. W.; Kraft, R.

    1987-01-01

    We examine the feasibility of an opening switch concept based on magnetic insulation in a coaxial thermionic diode. It is found that the impedance ratio between closed and open states of the diode is marginal for efficient energy transfer via this type of switch. The open, or insulated state of the diode is characterized by current leakage across the magnetic field which is associated with the presence of plasma waves.

  5. Material testing facilities and programs for plasma-facing component testing

    Science.gov (United States)

    Linsmeier, Ch.; Unterberg, B.; Coenen, J. W.; Doerner, R. P.; Greuner, H.; Kreter, A.; Linke, J.; Maier, H.

    2017-09-01

    Component development for operation in a large-scale fusion device requires thorough testing and qualification for the intended operational conditions. In particular environments are necessary which are comparable to the real operation conditions, allowing at the same time for in situ/in vacuo diagnostics and flexible operation, even beyond design limits during the testing. Various electron and neutral particle devices provide the capabilities for high heat load tests, suited for material samples and components from lab-scale dimensions up to full-size parts, containing toxic materials like beryllium, and being activated by neutron irradiation. To simulate the conditions specific to a fusion plasma both at the first wall and in the divertor of fusion devices, linear plasma devices allow for a test of erosion and hydrogen isotope recycling behavior under well-defined and controlled conditions. Finally, the complex conditions in a fusion device (including the effects caused by magnetic fields) are exploited for component and material tests by exposing test mock-ups or material samples to a fusion plasma by manipulator systems. They allow for easy exchange of test pieces in a tokamak or stellarator device, without opening the vessel. Such a chain of test devices and qualification procedures is required for the development of plasma-facing components which then can be successfully operated in future fusion power devices. The various available as well as newly planned devices and test stands, together with their specific capabilities, are presented in this manuscript. Results from experimental programs on test facilities illustrate their significance for the qualification of plasma-facing materials and components. An extended set of references provides access to the current status of material and component testing capabilities in the international fusion programs.

  6. Fluidic nanotubes and devices

    Science.gov (United States)

    Yang, Peidong; He, Rongrui; Goldberger, Joshua; Fan, Rong; Wu, Yiying; Li, Deyu; Majumdar, Arun

    2008-04-08

    Fluidic nanotube devices are described in which a hydrophilic, non-carbon nanotube, has its ends fluidly coupled to reservoirs. Source and drain contacts are connected to opposing ends of the nanotube, or within each reservoir near the opening of the nanotube. The passage of molecular species can be sensed by measuring current flow (source-drain, ionic, or combination). The tube interior can be functionalized by joining binding molecules so that different molecular species can be sensed by detecting current changes. The nanotube may be a semiconductor, wherein a tubular transistor is formed. A gate electrode can be attached between source and drain to control current flow and ionic flow. By way of example an electrophoretic array embodiment is described, integrating MEMs switches. A variety of applications are described, such as: nanopores, nanocapillary devices, nanoelectrophoretic, DNA sequence detectors, immunosensors, thermoelectric devices, photonic devices, nanoscale fluidic bioseparators, imaging devices, and so forth.

  7. Effect of fundus image devices for early diagnosis of primary open angle glaucoma%眼底图像分析系统在原发性开角型青光眼早期诊断中的作用

    Institute of Scientific and Technical Information of China (English)

    潘英姿

    2009-01-01

    眼底图像分析技术的迅速发展使视神经损害的直接定量检测成为可能,同时因其检测手段客观、结果可靠而日益受到重视.但由于临床医师对眼底图像分析技术如海德堡视网膜断层扫描、相干光断层扫描等在青光眼早期诊断中的意义仍存在认识上的分歧,因此有必要就此问题进行论述.有多数研究结果表明,现有的检测设备不仅在分辨率和重复性方面已经达到临床要求,而且能够较好地区分正常人和青光眼的眼底改变,但现阶段利用视神经结构定量指标来实现对青光眼的早期诊断,其敏感性和特异性尚不尽如人意.其原因是多方面的,如结构指标个体差异较大,缺乏完善的正常人数据库,缺乏达成共识的敏感而特异的诊断指标等.尽管如此,现有的研究趋势表明,利用图像分析技术测量青光眼性视神经损害已显示出令人鼓舞的临床应用前景,临床医师若能充分了解各种图像分析手段的优缺点,这些新的检测技术将成为早期诊断原发性开角型青光眼的有益补充手段.%Evaluation of the optic disc and retinal nerve fiber layer measurements (RNFL) with sterephotography is the current "gold standard" for the diagnosis of early primary open angle glaucoma (POAG), but it is still subjective and is dependent too much upon an experienced observer.Substantial variability exists in the interpretation of optic disc change over time.There are consistent evidences that image analysis devices such as optical coherence tomography (OCT) and Heidelberg retina tomograph (HRT-Ⅱ) can detect early to moderate glaucoma as well as expert assessment of stereoscopic optic disc and RNFL photographs.Optic disc and RNFL defect can be quantitatively measured by these devices.But the sensitivity and specificity of the measurements obtained with these devices are not good enough for the early diagnosis of POAG at this time due to several reasons, such as

  8. Insertion devices

    CERN Document Server

    Bahrdt, J

    2006-01-01

    The interaction of an insertion device with the electron beam in a storage ring is discussed. The radiation property including brightness, ux and polarization of an ideal and real planar and helical / elliptical device is described. The magnet design of planar, helical, quasiperiodic devices and of devices with a reduced on axis power density are resumed.

  9. FACTS technology for open access

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Summary of the present state of the art on the key technological developments in the FACTS (Flexible AC Transmission Systems) area, addressing in particular the open access aspects of networks and the scope for the application of FACTS devices therein. Contains the approved terms of reference. Definition of FACTS includes conventional devices such as phase shifting transformers, series capacitors and HVDC links for completeness and the possibility of combining them with FACTS devices to improve HVAC transmission system flexibility and control. (author)

  10. Electrosurgical plasmas

    Science.gov (United States)

    Stalder, Kenneth R.; McMillen, Donald F.; Woloszko, Jean

    2005-06-01

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  11. Electrosurgical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stalder, Kenneth R; McMillen, Donald F; Woloszko, Jean [ArthroCare Corp., Sunnyvale, CA 94085-3523 (United States)

    2005-06-07

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  12. Optimization of an open-focused microwave oven digestion procedure for determination of metals in diesel oil by inductively coupled plasma optical emission spectrometry.

    Science.gov (United States)

    Sant'Ana, Flavio W; Santelli, Ricardo E; Cassella, Alessandra R; Cassella, Ricardo J

    2007-10-01

    This work reports the optimization of a focused microwave assisted procedure for the wet acid dissolution of diesel oil in order to allow the determination of metals in the samples by inductively coupled plasma optical emission spectrometry (ICP-OES). The dissolution process was monitored by measuring residual carbon content (RCC), also by ICP-OES, in the final solutions obtained after application of digestion program. All experimental work was performed using a commercial sample of diesel oil containing 85.74+/-0.13% of carbon. The initial dissolution program comprised three steps: (i) carbonization with H(2)SO(4); (ii) oxidation with HNO(3) and (iii) final oxidation with H(2)O(2). During work it was verified that the first step played an important role on the dissolution process of this kind of sample. It is therefore, necessary to give a detailed optimization of such step. Employing the optimized conditions it was possible to digest 2.5 g of diesel oil with a 40 min-heating program. At these conditions, residual carbon content was always lower than 5%. Optimized methodology was applied in the determination of metals in three diesel oil samples by ICP-OES. Recovery tests were also performed by adding 10 microg of metals, as organic standards, to the samples before digestion. Recovery percentages always higher than 90% were obtained for the metals of interest (Al, Cu, Fe and Ni), except for Zn, which presented recoveries between 70 and 78%.

  13. Open access

    NARCIS (Netherlands)

    Valkenburg, P.M.

    2015-01-01

    Open access week Van 19 tot en met 25 oktober 2015 vond wereldwijd de Open Access Week plaats. Tijdens deze week werden er over de hele wereld evenementen georganiseerd waar open access een rol speelt. Ook in Nederland zijn er diverse symposia, workshops en debatten georganiseerd zoals het debat in

  14. Photoemission-based microelectronic devices

    Science.gov (United States)

    Forati, Ebrahim; Dill, Tyler J.; Tao, Andrea R.; Sievenpiper, Dan

    2016-11-01

    The vast majority of modern microelectronic devices rely on carriers within semiconductors due to their integrability. Therefore, the performance of these devices is limited due to natural semiconductor properties such as band gap and electron velocity. Replacing the semiconductor channel in conventional microelectronic devices with a gas or vacuum channel may scale their speed, wavelength and power beyond what is available today. However, liberating electrons into gas/vacuum in a practical microelectronic device is quite challenging. It often requires heating, applying high voltages, or using lasers with short wavelengths or high powers. Here, we show that the interaction between an engineered resonant surface and a low-power infrared laser can cause enough photoemission via electron tunnelling to implement feasible microelectronic devices such as transistors, switches and modulators. The proposed photoemission-based devices benefit from the advantages of gas-plasma/vacuum electronic devices while preserving the integrability of semiconductor-based devices.

  15. Gas-flow optimization studies on brass samples using closed and open types of laser ablation cells in inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Kantor, Tibor, E-mail: kantort@mafi.hu; Kiraly, Edit; Bertalan, Eva; Bartha, Andras

    2012-02-15

    The effect of the carrier gas flow rate on laser ablation inductively coupled mass spectrometry (LA-ICP-MS) signals of brass components (Cu, Zn, and Ni) were studied primarily with the use of a conventional closed ablation cell (UP-213) and with the use of an open ablation cell of our own construction. In the closed ablation cell configuration with the carrier gas flow rate in the range of 0.40-1.3 L min{sup -1} Ar, the MS signals increased significantly (an 8.2-fold increase for a Cu signal), and the Zn/Cu signal ratio increased 3.2 times. To identify the degree of fractionation, the conventional solution sample introduction method was selected as the reference method because it is expected free from fractionation for Cu and Zn. To obtain a theoretical value, calculations were made based on Saha's relationship of ionization, which resulted in fair agreement with the experimental results of the solution method. By comparing the Zn/Cu signal ratios obtained from both the LA and the solution method, a fractionation factor of 2.26 was deduced for these two components. To explain the increased signals described above, the transport efficiency as a function of the carrier gas flow rate was calculated for different particle size fractions based on existing theories. It was demonstrated that the large increase in the signals with carrier gas flow rate is predominantly due to processes taking place in the ablation cell (i.e., neither during the transportation nor in the ICP). The results of the novel fundamental works on aerosol formation under LA conditions were considered and complemented with the application of the Kelvin (Gibbs-Thomson) equation to calculate critical sizes of aerosol particles in the nucleating vapors of Cu, Zn, Ni and Pb elements. It was concluded that the noted increase of signals was due to the intensification of mixing of the expanding vapor-cloud with cold gas when applying an increasing carrier gas flow rate. It was also concluded that the

  16. Etching characteristics and mechanism of SiN(x) films for nano-devices in CH2F2/O2/Ar inductively coupled plasma: effect of O2 mixing ratio.

    Science.gov (United States)

    Son, Jinyoung; Efremov, Alexander; Yun, Sun Jin; Yeom, Geun Young; Kwonl, Kwang-ho

    2014-12-01

    Etching characteristics and mechanisms of low-temperature SiN(x) thin films for nano-devices in CH2F2/O2/Ar inductively-coupled plasmas were studied. The etching rates of SiN(x) thin films as well as the etching selectivities over Si and photoresist were measured in the range of 25-75% O2 in a feed gas at fixed CH2F2 content (25%), gas pressure (6 mTorr), input power (900 W), bias power (200 W), and total gas flow rate (40 sccm). Plasma parameters were analyzed using the Langmuir probe diagnostics and optical emission spectroscopy. The chemical states of the etched surfaces were examined by the X-ray photoelectron spectroscopy. It was found that the non-monotonic (with a maximum at about 50-60% O2) SiN(x) etching rate does not correlate with monotonically decreasing F atom flux and ion energy flux. It was proposed that, under the given set of experimental conditions, the SiN(x) etching process is also controlled by the O and H atom fluxes through the destruction of the fluorocarbon polymer layer.

  17. Arc Plasma Torch Modeling

    CERN Document Server

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  18. Homologous platelet-rich plasma for the treatment of knee osteoarthritis in selected elderly patients: an open-label, uncontrolled, pilot study.

    Science.gov (United States)

    Bottegoni, Carlo; Dei Giudici, Luca; Salvemini, Sergio; Chiurazzi, Enrico; Bencivenga, Rosella; Gigante, Antonio

    2016-04-01

    The objective of this study was to evaluate the safety and the effect of platelet-rich plasma (PRP) intra-articular injections obtained from blood donors (homologous PRP) on elderly patients with early or moderate knee osteoarthritis (OA) who are not candidates for autologous PRP treatment. A total of 60 symptomatic patients, aged 65-86 years, affected by hematologic disorders and early or moderate knee OA, were treated with 5 ml of homologous PRP intra-articular injections every 14 days for a total of three injections. Clinical evaluations before the treatment, and after 2 and 6 months were performed by International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS) and Equal Visual Analogue Scale (EQ VAS) scores. Adverse events and patient satisfaction were recorded. No severe complications were noted during the treatment and the follow-up period. A statistically significant improvement from basal evaluation to the 2-month follow-up visit was observed, whereas a statistically significant worsening from the 2-month to the 6-month follow-up visit was showed. The overall worst results were observed in patients aged 80 years or over and in those affected by minor bone attrition. It was found that 90% of patients were satisfied at the 6-month evaluation. Homologous PRP has an excellent safety profile but offers only a short-term clinical improvement in selected elderly patients with knee OA who are not candidates for autologous PRP treatment. Increasing age and developing degeneration result in a decreased potential for homologous PRP injection therapy. Further studies are needed to confirm these findings.

  19. Magnetohydrodynamic stability at the edge region in H-mode plasmas with long edge-localized-mode-free phases in the large helical device

    Science.gov (United States)

    Toi, K.; Ohdachi, S.; Ueda, R.; Watanabe, K. Y.; Nicolas, T.; Suzuki, Y.; Ogawa, K.; Tanaka, K.; Takemura, Y.; LHD Experiment Group

    2016-09-01

    Clear suppression of magnetic fluctuations associated with resistive interchange modes (RICs) is observed during long edge-localized-mode (ELM)-free phases of the H-mode plasma in an outward-shifted configuration of the Large Helical Decice, in which a steep pressure gradient is generated at the plasma edge in the magnetic hill. The ELM-free H-phase is interrupted by large amplitude ELMs which are thought to be induced through nonlinear evolution of the RICs having m  =  1/n  =  1 dominant component (m: poloidal mode number, n: toroidal one). The m  =  1/n  =  1 RIC amplitude is enhanced about 10 times compared with the H-phase level during each ELM. In most of the H-mode shots, the final ELM-free phase returns to L-phase by a large amplitude ELM. In the L-phase, the RIC amplitude is enhanced by a factor of ~3 compared with that in the H-phase, although the edge pressure gradient is reduced considerably. Linear resistive magnetohydrodynamic stability analysis is attempted using experimentally obtained equilibrium profiles. From the numerical analysis, the distance between the location of the steepest pressure gradient and the main mode resonance surface, i.e. the rotational transform ι  =  1, is found to be important for a large growth of the m  =  1/n  =  1 RIC in the H-phase.

  20. An uncontrolled open-label, multicenter study to monitor the antiviral activity and safety of inhaled zanamivir (as Rotadisk via Diskhaler device) among Chinese adolescents and adults with influenza-like illness

    Institute of Scientific and Technical Information of China (English)

    CAO Bin; XU Qian; HU Ke; CHEN Bai-yi; YU Yun-song; SONG Shu-fan; SHU Yue-long; WANG Chen; WANG Da-yan; YU Xiao-min; WEI Lu-qing; PU Zeng-hui; GAO Yan; WANG Jing; DONG Jian-ping; LI Xiao-ling

    2012-01-01

    Background It is the first multicenter clinical study in China to investigate zanamivir use among Chinese adolescents and adults with influenza-like illness (ILI) since 2009,when inhaled zanamivir (RELENZA(R)) was marketed in China.Methods An uncontrolled open-label,multicentre study to evaluate the antiviral activity,and safety of inhaled zanamivir (as Rotadisk via Diskhaler device); 10 mg administered twice daily for 5 days in subjects ≥12 years old with ILl.Patients were enrolled within 48 hours of onset and followed for eight days.Patients were defined as being influenza-positive if the real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) test had positive results.Results A total of 400 patients ≥12 years old were screened from 11 centers in seven provinces from March 2010 to January 2011.Three hundred and ninety-two patients who took at least one dose of zanamivir were entered into the safety analysis.The mean age was 33.8 years and 50% were male.Cardiovascular diseases and diabetes were the most common comorbidities.All the reported adverse events,such as rash,nasal ache,muscle ache,nausea,diarrhea,headache,occurred in less than 1% of subjects.Mild sinus bradycadia or arrhythmia occurred in four subjects (1%).Most of the adverse events were mild and did not require any change of treatment.No severe adverse events (SAE) or fatal cases were reported.Bronchospasm was found in a 38 years old woman whose symptoms disappeared after stopping zanamivir and without additional treatment.All the 61 influenza virus isolates (43 before enrollment,18 during treatment) proved to be sensitive to zanamivir.Conclusions Zanamivir is well tolerated by Chinese adolescents and adults with ILls.There is no evidence for the emergence of drug-resistant isolates during treatment with zanamivir.(ChiCTR-TNRC-10000938)