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Sample records for bottle plasma flows

  1. Plastic bottle oscillator: Rhythmicity and mode bifurcation of fluid flow

    OpenAIRE

    Kohira, Masahiro I.; Magome, Nobuyuki; Kitahata, Hiroyuki; Yoshikawa, Kenichi

    2007-01-01

    The oscillatory flow of water draining from an upside-down plastic bottle with a thin pipe attached to its head is studied as an example of a dissipative structure generated under far-from-equilibrium conditions. Mode bifurcation was observed in the water/air flow: no flow, oscillatory flow, and counter flow were found when the inner diameter of the thin pipe was changed. The modes are stable against perturbations. A coupled two-bottle system exhibits either in-phase or anti-phase self-synchr...

  2. Plastic bottle oscillator: Rhythmicity and mode bifurcation of fluid flow

    Science.gov (United States)

    Kohira, Masahiro I.; Magome, Nobuyuki; Kitahata, Hiroyuki; Yoshikawa, Kenichi

    2007-10-01

    The oscillatory flow of water draining from an upside-down plastic bottle with a thin pipe attached to its head is studied as an example of a dissipative structure generated under far-from-equilibrium conditions. Mode bifurcation was observed in the water/air flow: no flow, oscillatory flow, and counter flow were found when the inner diameter of the thin pipe was changed. The modes are stable against perturbations. A coupled two-bottle system exhibits either in-phase or anti-phase self-synchronization. These characteristic behaviors imply that the essential features of the oscillatory flow in a single bottle system can be described as a limit-cycle oscillation.

  3. Fluid dynamics following flow shut-off in bottle filling

    Science.gov (United States)

    Thete, Sumeet; Appathurai, Santosh; Gao, Haijing; Basaran, Osman

    2012-11-01

    Bottle filling is ubiquitous in industry. Examples include filling of bottles with shampoos and cleaners, engine oil and pharmaceuticals. In these examples, fluid flows out of a nozzle to fill bottles in an assembly line. Once the required volume of fluid has flowed out of the nozzle, the flow is shut off. However, an evolving fluid thread or string may remain suspended from the nozzle following flow shut-off and persist. This stringing phenomenon can be detrimental to a bottle filling operation because it can adversely affect line speed and filling accuracy by causing uncertainty in fill volume, product loss and undesirable marring of the bottles' exterior surfaces. The dynamics of stringing are studied numerically primarily by using the 1D, slender-jet approximation of the flow equations. A novel feature entails development and use of a new boundary condition downstream of the nozzle exit to expedite the computations. While the emphasis is on stringing of Newtonian fluids and use of 1D approximations, results will also be presented for situations where (a) the fluids are non-Newtonian and (b) the full set of equations are solved without invoking the 1D approximation. Phase diagrams will be presented that identify conditions for which stringing can be problematic.

  4. Milk Flow Rates from bottle nipples used after hospital discharge.

    Science.gov (United States)

    Pados, Britt Frisk; Park, Jinhee; Thoyre, Suzanne M; Estrem, Hayley; Nix, W Brant

    To test the milk flow rates and variability in flow rates of bottle nipples used after hospital discharge. Twenty-six nipple types that represented 15 common brands as well as variety in price per nipple and store location sold (e.g., Babies R' Us, Walmart, Dollar Store) were chosen for testing. Ten of each nipple type (n = 260 total) were tested by measuring the amount of infant formula expressed in 1 minute using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation (CV) were calculated. Flow rates of nipples within brand were compared statistically. Milk flow rates varied from 1.68 mL/min for the Avent Natural Newborn Flow to 85.34 mL/min for the Dr. Brown's Standard Y-cut. Variability between nipple types also varied widely, from .03 for the Dr. Brown's Standard Level 3 to .37 for MAM Nipple 1 Slow Flow. The extreme range of milk flow rates found may be significant for medically fragile infants being discharged home who are continuing to develop oral feeding skills. The name of the nipple does not provide clear information about the flow rate to guide parents in decision making. Variability in flow rates within nipples of the same type may complicate oral feeding for the medically fragile infant who may not be able to adapt easily to change in flow rates. Both flow rate and variability should be considered when guiding parents to a nipple choice.

  5. Milk flow rates from bottle nipples used after hospital discharge

    Science.gov (United States)

    Pados, Britt Frisk; Park, Jinhee; Thoyre, Suzanne M.; Estrem, Hayley; Nix, W. Brant

    2016-01-01

    Purpose To test the milk flow rates and variability in flow rates of bottle nipples used after hospital discharge. Study Design and Methods Twenty-six nipple types that represented 15 common brands as well as variety in price per nipple and store location sold (e.g., Babies R’ Us, Walmart, Dollar Store) were chosen for testing. Ten of each nipple type (n=260 total) were tested by measuring the amount of infant formula expressed in one minute using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation (CV) were calculated. Flow rates of nipples within brand were compared statistically. Results Milk flow rates varied from 1.68 mL/min for the Avent Natural Newborn Flow to 85.34 mL/min for the Dr. Brown’s Standard Y-cut. Variability between nipple types also varied widely, from .03 for the Dr. Brown’s Standard Level 3 to .37 for MAM Nipple 1 Slow Flow. Clinical Implications The extreme range of milk flow rates found may be significant for medically fragile infants being discharged home who are continuing to develop oral feeding skills. The name of the nipple does not provide clear information about the flow rate to guide parents in decision-making. Variability in flow rates within nipples of the same type may complicate oral feeding for the medically fragile infant who may not be able to adapt easily to change in flow rates. Both flow rate and variability should be considered when guiding parents to a nipple choice. PMID:27008466

  6. Confinement of plasma in a magnetic bottle induced by circularly polarized laser light

    Energy Technology Data Exchange (ETDEWEB)

    Eliezer, S.; Kolka, E.; Paiss, Y. [Plasma Physics Soreq Nuclear Research Center, Yavne 70600 (Israel)

    1994-10-05

    A concept of plasma confinement using a combination of inertial and magnetic methods is suggested. A miniature magnetic bottle with the megagauss field can be induced by circularly polarized laser radiation inside a good conductor vessel containing a plasma. The laser pulses also heat the plasma to {similar_to}5 KeV during a few nanoseconds. The Lawson criteria for a DT plasma might be satisfied for densities of the order 5{center_dot}10{sup 21} cm{sup {minus}3} and confinement time about 20 nsec.(AIP) {copyright}{ital American} {ital Institute} {ital of} {ital Physics} 1994

  7. Computational and experimental investigation of flow and fluid mixing in the roller bottle bioreactor.

    Science.gov (United States)

    Unger, D R; Muzzio, F J; Aunins, J G; Singhvi, R

    2000-10-20

    The fully three-dimensional velocity field in a roller bottle bioreactor is simulated for two systems (creeping flow and inertial flow conditions) using a control volume-finite element method, and validated experimentally using particle imaging velocimetry. The velocity fields and flow patterns are described in detail using velocity contour plots and tracer particle pathline computations. Bulk fluid mixing in the roller bottle is then examined using a computational fluid tracer program and flow visualization experiments. It is shown that the velocity fields and flow patterns are substantially different for each of these flow cases. For creeping flow conditions the flow streamlines consist of symmetric, closed three-dimensional loops; and for inertial flow conditions, streamlines consist of asymmetric toroidal surfaces. Fluid tracers remain trapped on these streamlines and are unable to contact other regions of the flow domain. As a result, fluid mixing is greatly hindered, especially in the axial direction. The lack of efficient axial mixing is verified computationally and experimentally. Such mixing limitations, however, are readily overcome by introducing a small-amplitude vertical rocking motion that disrupts both symmetry and recirculation, leading to much faster and complete axial mixing. The frequency of such motion is shown to have a significant effect on mixing rate, which is a critical parameter in the overall performance of roller bottles. Copyright 2000 John Wiley & Sons, Inc.

  8. Couette Flow of Unmagnetized Plasma

    CERN Document Server

    Collins, C; Cooper, C M; Flanagan, K; Khalzov, I V; Nornberg, M D; Seidlitz, B; Wallace, J; Forest, C B

    2014-01-01

    Differentially rotating flows of unmagnetized, highly conducting plasmas have been created in the Plasma Couette Experiment. Previously, hot-cathodes have been used to control plasma rotation by a stirring technique [C. Collins et al., Phys. Rev. Lett. 108, 115001(2012)] on the outer cylindrical boundary---these plasmas were nearly rigid rotors, modified only by the presence of a neutral particle drag. Experiments have now been extended to include stirring from an inner boundary, allowing for generalized Couette flow and opening a path for both hydrodynamic and magnetohydrodynamic experiments, as well as fundamental studies of plasma viscosity. Plasma is confined in a cylindrical, axisymmetric, multicusp magnetic field, with $T_e< 10$ eV, $T_i<1$ eV, and $n_e<10^{11}$ cm$^{-3}$. Azimuthal flows (up to 12 km/s, $M=V/c_s\\sim 0.7$) are driven by edge ${\\bf J \\times B}$ torques in helium, neon, argon, and xenon plasmas. We present measurements of a self-consistent, rotation-induced, species-dependent rad...

  9. Milk Flow Rates From Bottle Nipples Used for Feeding Infants Who Are Hospitalized

    Science.gov (United States)

    Park, Jinhee; Thoyre, Suzanne M.; Estrem, Hayley; Nix, W. Brant

    2015-01-01

    Purpose This study tested the milk flow rates and variability in flow of currently available nipples used for bottle-feeding infants who are hospitalized. Method Clinicians in 3 countries were surveyed regarding nipples available to them for feeding infants who are hospitalized. Twenty-nine nipple types were identified, and 10 nipples of each type were tested by measuring the amount of infant formula expressed in 1 min using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation were used to compare nipples within brand and within category (i.e., Slow, Standard, Premature). Results Flow rates varied widely between nipples, ranging from 2.10 mL/min for the Enfamil Cross-Cut to 85.34 mL/min for the Dr. Brown's Y-Cut Standard Neck. Variability of flow rates among nipples of the same type ranged from a coefficient of variation of 0.05 for Dr. Brown's Level 1 Standard- and Wide-Neck to 0.42 for the Enfamil Cross-Cut. Mean coefficient of variation by brand ranged from 0.08 for Dr. Brown's to 0.36 for Bionix. Conclusions Milk flow is an easily manipulated variable that may contribute to the degree of physiologic instability experienced by infants who are medically fragile during oral feeding. This study provides clinicians with information to guide appropriate selection of bottle nipples for feeding infants who are hospitalized. PMID:26172340

  10. Milk Flow Rates From Bottle Nipples Used for Feeding Infants Who Are Hospitalized.

    Science.gov (United States)

    Pados, Britt F; Park, Jinhee; Thoyre, Suzanne M; Estrem, Hayley; Nix, W Brant

    2015-11-01

    This study tested the milk flow rates and variability in flow of currently available nipples used for bottle-feeding infants who are hospitalized. Clinicians in 3 countries were surveyed regarding nipples available to them for feeding infants who are hospitalized. Twenty-nine nipple types were identified, and 10 nipples of each type were tested by measuring the amount of infant formula expressed in 1 min using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation were used to compare nipples within brand and within category (i.e., Slow, Standard, Premature). Flow rates varied widely between nipples, ranging from 2.10 mL/min for the Enfamil Cross-Cut to 85.34 mL/min for the Dr. Brown's Y-Cut Standard Neck. Variability of flow rates among nipples of the same type ranged from a coefficient of variation of 0.05 for Dr. Brown's Level 1 Standard- and Wide-Neck to 0.42 for the Enfamil Cross-Cut. Mean coefficient of variation by brand ranged from 0.08 for Dr. Brown's to 0.36 for Bionix. Milk flow is an easily manipulated variable that may contribute to the degree of physiologic instability experienced by infants who are medically fragile during oral feeding. This study provides clinicians with information to guide appropriate selection of bottle nipples for feeding infants who are hospitalized.

  11. Sheared flows and turbulence in fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Pedrosa, M A [Laboratorio Nacional de Fusion, Asociacion EURATOM/CIEMAT, 28040-Madrid (Spain); Carreras, B A [Laboratorio Nacional de Fusion, Asociacion EURATOM/CIEMAT, 28040-Madrid (Spain); Hidalgo, C [Laboratorio Nacional de Fusion, Asociacion EURATOM/CIEMAT, 28040-Madrid (Spain); Silva, C [Centro de Fusao Nuclear, Instituto Superior Tecnico, Associaccao EURATOM/IST, 1049-001-Lisbon (Portugal); Hron, M [Institute of Plasma Physics, Association EURATOM/IPP.CR, AS CR Prague (Czech Republic); GarcIa, L [Universidad Carlos III, 28911-Leganes, Madrid (Spain); Alonso, J A [Laboratorio Nacional de Fusion, Asociacion EURATOM/CIEMAT, 28040-Madrid (Spain); Calvo, I [Laboratorio Nacional de Fusion, Asociacion EURATOM/CIEMAT, 28040-Madrid (Spain); Pablos, J L de [Laboratorio Nacional de Fusion, Asociacion EURATOM/CIEMAT, 28040-Madrid (Spain); Stoeckel, J [Institute of Plasma Physics, Association EURATOM/IPP.CR, AS CR Prague (Czech Republic)

    2007-12-15

    The universality of the observed characteristics of sheared flows points to a general ingredient to explain the damping/driving mechanisms responsible for the development of these flows in the plasma boundary region of fusion devices. Experiments in the TJ-II stellarator showing that the generation of spontaneous sheared flows at the plasma edge requires a minimum plasma density or density gradient, open a unique possibility to characterize the dynamics of sheared flow development in fusion plasmas. The effective viscosity at the plasma edge can be deduced by means of the decay rate of the perpendicular flow measurement once the driving force has been removed. Changes in the plasma rotation and turbulence have been studied when an electric field is externally applied at the plasma edge. The relaxation of flows and radial electric fields has been compared in the edge plasma region of TJ-II stellarator and CASTOR tokamak showing a striking similarity. The findings can help to test neoclassical and anomalous damping mechanisms in fusion plasmas. Finally, the emergence of the plasma edge sheared flow as a function of plasma density can be explained using a simple second-order phase transition model that reproduces many of the features of the TJ-II experimental data while capturing the qualitative features of the transition near the critical point.

  12. A topological analysis of plasma flow structures

    Science.gov (United States)

    Carreras, Benjamin A.; Llerena Rodríguez, Irene; García, Luis

    2013-09-01

    A new topological analysis of the plasma flow structures is presented for some pressure-gradient-driven turbulence results. The analysis is done by separating the structures into radial layers and studying each layer separately. This allows for the identification of flow cycles and flow filaments and the determination of the life of the cycles and length of the filaments.

  13. 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.

  14. Taylor-Couette flow of unmagnetized plasma

    Science.gov (United States)

    Collins, C.; Clark, M.; Cooper, C. M.; Flanagan, K.; Khalzov, I. V.; Nornberg, M. D.; Seidlitz, B.; Wallace, J.; Forest, C. B.

    2014-04-01

    Differentially rotating flows of unmagnetized, highly conducting plasmas have been created in the Plasma Couette Experiment. Previously, hot-cathodes have been used to control plasma rotation by a stirring technique [C. Collins et al., Phys. Rev. Lett. 108, 115001 (2012)] on the outer cylindrical boundary—these plasmas were nearly rigid rotors, modified only by the presence of a neutral particle drag. Experiments have now been extended to include stirring from an inner boundary, allowing for generalized circular Couette flow and opening a path for both hydrodynamic and magnetohydrodynamic experiments, as well as fundamental studies of plasma viscosity. Plasma is confined in a cylindrical, axisymmetric, multicusp magnetic field, with Te torques in helium, neon, argon, and xenon plasmas, and the experiment has already achieved Rm ˜ 65 and Pm ˜0.2-12. We present measurements of a self-consistent, rotation-induced, species-dependent radial electric field, which acts together with pressure gradient to provide the centripetal acceleration for the ions. The maximum flow speeds scale with the Alfvén critical ionization velocity, which occurs in partially ionized plasma. A hydrodynamic stability analysis in the context of the experimental geometry and achievable parameters is also explored.

  15. Bodies in flowing plasmas - Laboratory studies

    Science.gov (United States)

    Stone, N. H.; Samir, U.

    1981-01-01

    A brief review of early rudimentary laboratory studies of bodies in flowing, rarefied plasmas is presented (e.g., Birkeland, 1908), along with a discussion of more recent parametric studies conducted in steady plasma wind tunnels, which includes the study by Hall et al. (1964), in which a strong ion density enhancement in the center of the ion void created downstream from the body was observed. Good agreement was found between the experimental results and theoretical calculations which omit ion thermal motion. Examples in which in situ data on the interaction between satellites and the ionospheric plasma have been elucidated by the laboratory results are presented, and include evidence for a midwake axial ion peak, and ion current density in the near-wake region. The application of the ionospheric laboratory to basic space plasma physics is discussed, and its application to some types of solar system plasma phenomena is illustrated.

  16. Bodies in flowing plasmas - Spacecraft measurements

    Science.gov (United States)

    Samir, U.

    1981-01-01

    Results are reviewed from in-situ measurements relevant to the interaction of bodies in flowing plasmas. A brief discussion is given of the interaction in the general context of space plasma physics, including possible applications to solar-system plasmas. Attention is given to the mode of experimentation in the Shuttle/Spacelab era. It is noted that the majority of in-situ investigations during the past decade were limited to the very near surface of ionospheric satellites. It is expected that experiments to be carried out on board the Spacelab/Orbiter will make possible well-planned controlled experiments in the area of body-plasma interactions in its widest sense.

  17. Hot Plasma Flows in the Solar Corona

    Science.gov (United States)

    Shibasaki, K.

    2012-12-01

    The Solar Corona is a non-equilibrium open system. Energy and mass are supplied from the lower atmosphere and flow upwards through the corona into the interplanetary space. Steady state could be possible but not equilibrium state. Temperature of the corona varies depending on solar activities. However, even under very quite state, coronal temperature is still kept around million degrees. Coronal heating mechanisms have to work under such condition. Temperature of plasma is an averaged kinetic energy of random motion of particles. Motion of charged particles in magnetic field generates Lorenz force and particles gyrate around magnetic field lines. Gyration of charged particles generates magnetic moment which is directed anti-parallel to the surrounding magnetic field. This is the origin of diamagnetism of plasma. Each particle can be considered as a small magnet directed opposite to the surrounding magnetic field. When these magnets are put in inhomogeneous magnetic field, they are pushed toward weak field region. In case of open magnetic field region in the solar corona, plasma particles are pushed upwards. If this force (diamagnetic or mirror force) exceeds the gravity force, plasma flows upwards. Magnetic moment of each charged particle in thermal plasma is proportional to temperature and inversely proportional to magnetic field strength. The condition for plasma to flow upwards in an open magnetic field is that the scale length of the change of magnetic field strength is shorter than the hydrostatic scale length, which is determined by temperature and the gravity acceleration. This can be a mechanism to regulate the coronal temperature around million degree. The solar corona is filled with magnetic field, which is rooted at the photosphere in the form of flux tubes. Flux tubes connect directly the corona and the sub-photospheric layer where temperature is higher than the photosphere. Hot plasma, trapped in the flux tubes when they are generated around the bottom

  18. Ion thruster charge-exchange plasma flow

    Science.gov (United States)

    Carruth, M. R., Jr.; Gabriel, S. B.; Kitamura, S.

    1982-01-01

    The electron bombardment ion thruster has been under development for a number of years and during this time, studies of the plasmas produced by the thrusters and their interactions with spacecraft have been evaluated, based on available data. Due to diagnostic techniques used and facility effects, there is uncertainty as to the reliability of data from these early studies. This paper presents data on the flow of the charge-exchange plasma produced just downstream of the thruster's ion optics. The 'end-effect' of a cylindrical Langmuir probe is used to determine ion density and directed ion velocity. Results are compared with data obtained from a retarding potential analyzer-Faraday cup.

  19. Flowing dusty plasma experiments: Generation of flow and measurement techniques

    CERN Document Server

    Jaiswal, S; Sen, A

    2016-01-01

    A variety of experimental techniques for the generation of subsonic/supersonic dust fluid flows and means of measuring such flow velocities are presented. The experiments have been carried out in a $\\Pi-$shaped Dusty Plasma Experimental (DPEx) device with micron size kaolin/Melamine Formaldehyde (MF) particles embedded in a background of Argon plasma created by a direct current (DC) glow discharge. A stationary dust cloud is formed over the cathode region by precisely balancing the pumping speed and gas flow rate. A flow of dust particles/fluid is generated by additional gas injection from a single or dual locations or by altering the dust confining potential. The flow velocity is then estimated by three different techniques, namely, by super Particle Identification (sPIT) code, Particle Image Velocimetry (PIV) analysis and the excitation of Dust Acoustic Waves (DAWs). The results obtained from these three different techniques along with their merits and demerits are discussed. An estimation of the neutral dr...

  20. Plasma actuators for bluff body flow control

    Science.gov (United States)

    Kozlov, Alexey V.

    The aerodynamic plasma actuators have shown to be efficient flow control devices in various applications. In this study the results of flow control experiments utilizing single dielectric barrier discharge plasma actuators to control flow separation and unsteady vortex shedding from a circular cylinder in cross-flow are reported. This work is motivated by the need to reduce landing gear noise for commercial transport aircraft via an effective streamlining created by the actuators. The experiments are performed at Re D = 20,000...164,000. Circular cylinders in cross-flow are chosen for study since they represent a generic flow geometry that is similar in all essential aspects to a landing gear oleo or strut. The minimization of the unsteady flow separation from the models and associated large-scale wake vorticity by using actuators reduces the radiated aerodynamic noise. Using either steady or unsteady actuation at ReD = 25,000, Karman shedding is totally eliminated, turbulence levels in the wake decrease significantly and near-field sound pressure levels are reduced by 13.3 dB. Unsteady actuation at an excitation frequency of St D = 1 is found to be most effective. The unsteady actuation also has the advantage that total suppression of shedding is achieved for a duty cycle of only 25%. However, since unsteady actuation is associated with an unsteady body force and produces a tone at the actuation frequency, steady actuation is more suitable for noise control applications. Two actuation strategies are used at ReD = 82,000: spanwise and streamwise oriented actuators. Near field microphone measurements in an anechoic wind tunnel and detailed study of the near wake using LDA are presented in the study. Both spanwise and streamwise actuators give nearly the same noise reduction level of 11.2 dB and 14.2 dB, respectively, and similar changes in the wake velocity profiles. The contribution of the actuator induced noise is found to be small compared to the natural shedding

  1. Multi-Scale Investigation of Sheared Flows In Magnetized Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Edward, Jr., Thomas [Auburn Univ., Auburn, AL (United States)

    2014-09-19

    Flows parallel and perpendicular to magnetic fields in a plasma are important phenomena in many areas of plasma science research. The presence of these spatially inhomogeneous flows is often associated with the stability of the plasma. In fusion plasmas, these sheared flows can be stabilizing while in space plasmas, these sheared flows can be destabilizing. Because of this, there is broad interest in understanding the coupling between plasma stability and plasma flows. This research project has engaged in a study of the plasma response to spatially inhomogeneous plasma flows using three different experimental devices: the Auburn Linear Experiment for Instability Studies (ALEXIS) and the Compact Toroidal Hybrid (CTH) stellarator devices at Auburn University, and the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory. This work has shown that there is a commonality of the plasma response to sheared flows across a wide range of plasma parameters and magnetic field geometries. The goal of this multi-device, multi-scale project is to understand how sheared flows established by the same underlying physical mechanisms lead to different plasma responses in fusion, laboratory, and space plasmas.

  2. Inertial plasma confinement in a miniature magnetic bottle induced by circularly polarized laser light

    Energy Technology Data Exchange (ETDEWEB)

    Kolka, E. (Plasma Physics Group, SOREQ N.R.C., Yavne (Israel)); Eliezer, S. (Plasma Physics Group, SOREQ N.R.C., Yavne (Israel)); Paiss, Y. (Plasma Physics Group, SOREQ N.R.C., Yavne (Israel))

    1993-08-30

    A megagauss magnetic field generated by circularity polarized laser light is used to get confinement of a plasma contained in a good conductor vessel. In this scheme the inertial confinement is supported by the magnetic forces and the Lawson criterion for a DT plasma might be achieved. (orig.)

  3. FLUIDS, PLASMAS AND ELECTRIC DISCHARGES: The influence of the structures and compounds of DLC coatings on the barrier properties of PET bottles

    Science.gov (United States)

    Yang, Li; Wang, Zhen-Duo; Zhang, Shou-Ye; Yang, Li-Zhen; Chen, Qiang

    2009-12-01

    To reduce the oxygen transmission rate through a polyethylene terephthalate (PET) bottle (an organic plastic) diamond-like carbon (DLC) coatings on the inner surface of the PET bottle were deposited by radio frequency plasma-enhanced chemical vapour deposition (RF-PECVD) technology with C2H2 as the source of carbon and Ar as the diluted gas. As the barrier layer to humidity and gas permeation, this paper analyses the DLC film structure, composition, morphology and barrier properties by Fourier transform infrared, atomic force microscopy, scanning electron microscopy and oxygen transmission rate in detail. From the spectrum, it is found that the DLC film mainly consists of sp3 bonds. The barrier property of the films is significantly relevant to the sp3 bond concentration in the coating, the film thickness and morphology. Additionally, it is found that DLC film deposited in an inductively coupled plasma enhanced capacitively coupled plasma source shows a compact, homogeneous and crack-free surface, which is beneficial for a good gas barrier property in PET bottles.

  4. Fluid Dynamics of Bottle Filling

    Science.gov (United States)

    McGough, Patrick; Gao, Haijing; Appathurai, Santosh; Basaran, Osman

    2011-11-01

    Filling of bottles is a widely practiced operation in a large number of industries. Well known examples include filling of ``large'' bottles with shampoos and cleaners in the household products and beauty care industries and filling of ``small'' bottles in the pharmaceutical industry. Some bottle filling operations have recently drawn much attention from the fluid mechanics community because of the occurrence of a multitude of complex flow regimes, transitions, and instabilities such as mounding and coiling that occur as a bottle is filled with a fluid. In this talk, we present a primarily computational study of the fluid dynamical challenges that can arise during the rapid filling of bottles. Given the diversity of fluids used in filling applications, we consider four representative classes of fluids that exhibit Newtonian, shear-thinning, viscoelastic, and yield-stress rheologies. The equations governing the dynamics of bottle filling are solved either in their full 3D but axisymmetric form or using the slender-jet approximation.

  5. Plasma flow in recycling region of tokamak divertor and plasma recombination

    Energy Technology Data Exchange (ETDEWEB)

    Soboleva, T.K. [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico). Inst. de Ciencias Nucleares; Krasheninnikov, S.I.; Pigarov, A.Yu.

    1997-12-31

    We investigate the effects of hydrogen molecules and plasma recombination on self-consistent plasma-neutral gas interactions in the recycling region of a tokamak divertor. We treat the plasma flow in a fluid approximation retaining the effects of plasma recombination and employing a Knudsen neutral transport model for a `gas box` divertor geometry. For the model of plasma-neutral interactions we employ we find: a) molecular activated recombination is a dominant channel of divertor plasma recombination; and b) plasma recombination is a key element leading to a decrease in the plasma flux onto the target and substantial plasma pressure drop which are the main features of detached divertor regimes. (author)

  6. Effect of Energetic Plasma Flux on Flowing Liquid Lithium Surfaces

    Science.gov (United States)

    Kalathiparambil, Kishor; Jung, Soonwook; Christenson, Michael; Fiflis, Peter; Xu, Wenyu; Szott, Mathew; Ruzic, David

    2014-10-01

    An operational liquid lithium system with steady state flow driven by thermo-electric magneto-hydrodynamic force and capable of constantly refreshing the plasma exposed surface have been demonstrated at U of I. To evaluate the system performance in reactor relevant conditions, specifically to understand the effect of disruptive plasma events on the performance of the liquid metal PFCs, the setup was integrated to a pulsed plasma generator. A coaxial plasma generator drives the plasma towards a theta pinch which preferentially heats the ions, simulating ELM like flux, and the plasma is further guided towards the target chamber which houses the flowing lithium system. The effect of the incident flux is examined using diagnostic tools including triple Langmuir probe, calorimeter, rogowski coils, Ion energy analyzers, and fast frame spectral image acquisition with specific optical filters. The plasma have been well characterized and a density of ~1021 m-3, with electron temperature ~10 - 20 eV is measured, and final plasma velocities of 34 - 74 kms-1 have been observed. Calorimetric measurements using planar molybdenum targets indicate a maximum plasma energy (with 6 kV plasma gun and 20 kV theta pinch) of 0.08 MJm-2 with plasma divergence effects resulting in marginal reduction of 40 +/- 23 J in plasma energy. Further results from the other diagnostic tools, using the flowing lithium targets and the planar targets coated with lithium will be presented. DOE DE-SC0008587.

  7. Effect of Plasma Gas Flow Direction on Hydrophilicity of Polymer by Small Zone Cold Plasma Treatment and Hydrophobic Plasma Treatment

    OpenAIRE

    Sheng-Hsiang Hsu; Ko-Shao Chen; Hong-Ru Lin; Shu-Ju Chang; Tzu-Piao Tang

    2009-01-01

    Plasma treatment is the most popular surface modification process of polymers. A small cold plasma zone treatment is an important modification technique in modern industry. In this study, the effect of gas flow direction on plasma treatment was investigated. In order to decrease the plasma zone area, we added a separate cylinder to surround the upper electrode. The separate cylinder is effective in limiting the plasma discharge area, and we could find a light and dark area in the vacuum chamb...

  8. Partial microwave-assisted wet digestion of animal tissue using a baby-bottle sterilizer for analyte determination by inductively coupled plasma optical emission spectrometry

    Science.gov (United States)

    Matos, Wladiana O.; Menezes, Eveline A.; Gonzalez, Mário H.; Costa, Letícia M.; Trevizan, Lilian C.; Nogueira, Ana Rita A.

    2009-06-01

    A procedure for partial digestion of bovine tissue is proposed using polytetrafluoroethylene (PTFE) micro-vessels inside a baby-bottle sterilizer under microwave radiation for multi-element determination by inductively coupled plasma optical emission spectrometry (ICP OES). Samples were directly weighed in laboratory-made polytetrafluoroethylene vessels. Nitric acid and hydrogen peroxide were added to the uncovered vessels, which were positioned inside the baby-bottle sterilizer, containing 500 mL of water. The hydrogen peroxide volume was fixed at 100 µL. The system was placed in a domestic microwave oven and partial digestion was carried out for the determination of Ca, Cu, Fe, Mg, Mn and Zn by inductively coupled plasma optical emission spectrometry. The single-vessel approach was used in the entire procedure, to minimize contamination in trace analysis. Better recoveries and lower residual carbon content (RCC) levels were obtained under the conditions established through a 2 4-1 fractional factorial design: 650 W microwave power, 7 min digestion time, 50 µL nitric acid and 50 mg sample mass. The digestion efficiency was ascertained according to the residual carbon content determined by inductively coupled plasma optical emission spectrometry. The accuracy of the proposed procedure was checked against two certified reference materials.

  9. Jet flow and premixed jet flame control by plasma swirler

    Science.gov (United States)

    Li, Gang; Jiang, Xi; Zhao, Yujun; Liu, Cunxi; Chen, Qi; Xu, Gang; Liu, Fuqiang

    2017-04-01

    A swirler based on dielectric barrier discharge plasma actuators is designed and its effectiveness in both jet flow and premixed jet flame control is demonstrated. In contrast to traditional spanwise-oriented actuators, plasma actuators are placed along the axial direction of the injector to induce a circumferential velocity to the main flow and create a swirl flow without any insertion or moving part. In the DBD plasma swirl injector, the discharge does not ignite the mixture nor does it induce flashback. Flame visualization is obtained by cameras while velocity profiles are obtained by Laser Doppler Anemometry measurements. The results obtained indicate the effectiveness of the new design.

  10. Effects of Nasal Continuous Positive Airway Pressure and High-Flow Nasal Cannula on Sucking, Swallowing, and Breathing during Bottle-Feeding in Lambs

    Directory of Open Access Journals (Sweden)

    Nathalie Samson

    2018-01-01

    Full Text Available The use of prolonged respiratory support under the form of high-flow nasal cannula (HFNC or nasal continuous positive airway pressure (nCPAP is frequent in newborn infants. Introduction of oral feeding under such nasal respiratory support is, however, highly controversial among neonatologists, due to the fear that it could disrupt sucking, swallowing, and breathing coordination and in turn induce cardiorespiratory events. The recent observation of tracheal aspirations during bottle-feeding in preterm infants under nCPAP justifies the use of animal models to perform more comprehensive physiological studies on the subject, in order to gain further insights for clinical studies. The objective of this study was to assess and compare the impact of HFNC and nCPAP on bottle-feeding in newborn lambs, in terms of bottle-feeding efficiency and safety as well as sucking–swallowing–breathing coordination. Eight full-term lambs were instrumented to record sucking, swallowing, and respiration as well as electrocardiogram and oxygenation. Lambs were bottle-fed in a standardized manner during three randomly ordered conditions, namely nCPAP 6 cmH2O, HFNC 7 L/min, and no respiratory support. Results revealed that nCPAP decreased feeding duration [25 vs. 31 s (control vs. 57 s (HFNC, p = 0.03] and increased the rate of milk transfer [2.4 vs. 1.9 mL/s (control vs.1.1 mL/s (HFNC, p = 0.03]. No other indices of bottle-feeding safety or sucking–swallowing–breathing coordination were significantly altered by HFNC or nCPAP. In conclusion, our results obtained in full-term newborn lambs suggest that: (i nCPAP 6 cmH2O, but not HFNC 7 L/min, increases bottle-feeding efficiency; (ii bottle-feeding is safe under nCPAP 6 cmH2O and HFNC 7 L/min, with no significant alteration in sucking–swallowing–breathing coordination. The present informative and reassuring data in full-term healthy lambs must be complemented by similar studies in

  11. Thin current sheets caused by plasma flow gradients in space and astrophysical plasma

    Directory of Open Access Journals (Sweden)

    D. H. Nickeler

    2010-08-01

    Full Text Available Strong gradients in plasma flows play a major role in space and astrophysical plasmas. A typical situation is that a static plasma equilibrium is surrounded by a plasma flow, which can lead to strong plasma flow gradients at the separatrices between field lines with different magnetic topologies, e.g., planetary magnetospheres, helmet streamers in the solar corona, or at the boundary between the heliosphere and interstellar medium. Within this work we make a first step to understand the influence of these flows towards the occurrence of current sheets in a stationary state situation. We concentrate here on incompressible plasma flows and 2-D equilibria, which allow us to find analytic solutions of the stationary magnetohydrodynamics equations (SMHD. First we solve the magnetohydrostatic (MHS equations with the help of a Grad-Shafranov equation and then we transform these static equilibria into a stationary state with plasma flow. We are in particular interested to study SMHD-equilibria with strong plasma flow gradients perpendicular to separatrices. We find that induced thin current sheets occur naturally in such situations. The strength of the induced currents depend on the Alfvén Mach number and its gradient, and on the magnetic field.

  12. High energy density Z-pinch plasmas using flow stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Shumlak, U., E-mail: shumlak@uw.edu; Golingo, R. P., E-mail: shumlak@uw.edu; Nelson, B. A., E-mail: shumlak@uw.edu; Bowers, C. A., E-mail: shumlak@uw.edu; Doty, S. A., E-mail: shumlak@uw.edu; Forbes, E. G., E-mail: shumlak@uw.edu; Hughes, M. C., E-mail: shumlak@uw.edu; Kim, B., E-mail: shumlak@uw.edu; Knecht, S. D., E-mail: shumlak@uw.edu; Lambert, K. K., E-mail: shumlak@uw.edu; Lowrie, W., E-mail: shumlak@uw.edu; Ross, M. P., E-mail: shumlak@uw.edu; Weed, J. R., E-mail: shumlak@uw.edu [Aerospace and Energetics Research Program, University of Washington, Seattle, Washington, 98195-2250 (United States)

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and

  13. Generalized superconducting flows -- Plasma confinement, organization

    Energy Technology Data Exchange (ETDEWEB)

    Mahajan, S.M.

    1997-01-01

    Complete expulsion of magnetic vorticity is used to characterize the superconducting flow. It is shown that a simple, intuitive, but speculative generalization can serve as a paradigm for a variety of organized flows.

  14. Interaction between calf thymus DNA and cationic bottle-brush copolymers: equilibrium and stopped-flow kinetic studies.

    Science.gov (United States)

    Dey, Debabrata; Maiti, Chiranjit; Maiti, Souvik; Dhara, Dibakar

    2015-01-28

    Interaction studies between a set of poly(ethylene glycol) (PEG) based cationic bottle-brush block copolymers (BBCPs) and calf thymus DNA (ctDNA) were carried out using steady state fluorescence spectroscopy, UV melting experiments and dynamic light scattering measurements. Results suggested that these cationic block copolymers could effectively bind with negatively charged DNA. Although electrostatic interaction is believed to be the predominant contributing factor in the overall binding process, hydrophobic interactions between the PEG chains and the DNA base pairs affected the binding process to some extent. Cationic block copolymers with higher PEG content were found to bind more efficiently with DNA. DLS studies revealed the details of the compaction process of elongated DNA chains into a globular structure in the presence of cationic block copolymers. Further, the kinetics of the DNA-cationic BBCP binding process was monitored via the stopped-flow fluorescence technique. In general, a two-step mechanistic pathway was observed in the case of all the cationic BBCP-DNA binding processes and the relative rate constants (k1'and k2') were found to increase with the copolymer concentration. The first step corresponded to a fast electrostatic binding between the cationic BBCP and the anionic ctDNA, while the slow second step indicated a conformational change of the DNA polyplex that led to DNA compaction. In addition to the polymer-DNA charge ratios, the PEG content in the cationic BBCPs was found to have a significant effect on the kinetics of the ctDNA-BBCP polyplex formation.

  15. Bottled Water and Fluoride

    Science.gov (United States)

    ... What's this? Submit What's this? Submit Button Bottled Water Recommend on Facebook Tweet Share Compartir Consumers drink ... questions about bottled water and fluoride. Does bottled water contain fluoride? Bottled water products may contain fluoride, ...

  16. Optical diagnostics in supersonic plasma flows: Purging fluid effects

    Energy Technology Data Exchange (ETDEWEB)

    Bouchillon, C.W.; Norton, O.P.; Cook, R.L.

    1993-01-01

    Magnetohydrodynamic topping cycles are being planned for electrical power production in conjunction with conventional fossil fueled power plants. In order to develop proper designs and to provide for better control and safety, it is desirable to make measurements in the plasma flows which are used in the MHD process. Noninvasive optically based instruments are well suited to this purpose. In order to use these optically based instruments, optically transparent viewports are required to allow observations of the plasma flow conditions. A purge/impulse fluid flow system has been devised to provide continuous optical access to the flow by DIAL. The presence of the purge flows in the supersonic section of the MHD system may have an effect on the flow characteristics and consequently, the effectiveness of the electrical energy generation or on the long-term reliability of the power train. A numerical evaluation of the resulting flow field in a supersonic duct with purge flow viewports has been made and results are presented which illustrate the predicted effects of the purge flow under steady state conditions. The only significant effect on the plasma flow was in the temperature distribution near the wall downstream and in the plane of the viewpoints.

  17. Optical diagnostics in supersonic plasma flows: Purging fluid effects

    Energy Technology Data Exchange (ETDEWEB)

    Bouchillon, C.W.; Norton, O.P.; Cook, R.L.

    1993-03-01

    Magnetohydrodynamic topping cycles are being planned for electrical power production in conjunction with conventional fossil fueled power plants. In order to develop proper designs and to provide for better control and safety, it is desirable to make measurements in the plasma flows which are used in the MHD process. Noninvasive optically based instruments are well suited to this purpose. In order to use these optically based instruments, optically transparent viewports are required to allow observations of the plasma flow conditions. A purge/impulse fluid flow system has been devised to provide continuous optical access to the flow by DIAL. The presence of the purge flows in the supersonic section of the MHD system may have an effect on the flow characteristics and consequently, the effectiveness of the electrical energy generation or on the long-term reliability of the power train. A numerical evaluation of the resulting flow field in a supersonic duct with purge flow viewports has been made and results are presented which illustrate the predicted effects of the purge flow under steady state conditions. The only significant effect on the plasma flow was in the temperature distribution near the wall downstream and in the plane of the viewpoints.

  18. Plasma Control of Turbine Secondary Flows Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose Phase I and II efforts that will focus on turbomachinery flow control. Specifically, the present work will investigate active control in a high speed...

  19. Jet flow and premixed jet flame control by plasma swirler

    Energy Technology Data Exchange (ETDEWEB)

    Li, Gang, E-mail: ligang@iet.cn [Key laboratory of light duty gas turbine, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Jiang, Xi [School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Zhao, Yujun [School of Mechanism, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Liu, Cunxi [Key laboratory of light duty gas turbine, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Chen, Qi [School of Mechanism, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Xu, Gang; Liu, Fuqiang [Key laboratory of light duty gas turbine, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China)

    2017-04-04

    A swirler based on dielectric barrier discharge plasma actuators is designed and its effectiveness in both jet flow and premixed jet flame control is demonstrated. In contrast to traditional spanwise-oriented actuators, plasma actuators are placed along the axial direction of the injector to induce a circumferential velocity to the main flow and create a swirl flow without any insertion or moving part. In the DBD plasma swirl injector, the discharge does not ignite the mixture nor does it induce flashback. Flame visualization is obtained by cameras while velocity profiles are obtained by Laser Doppler Anemometry measurements. The results obtained indicate the effectiveness of the new design. - Highlights: • The discharge does not ignite the mixture nor does it induce flashback. • The prominent advantage of this novel plasma swirler is its swirl number adjustable without any mechanical movement. • The frequency of the plasma swirler is adjustable. • The plasma swirler can be used as an oscillator to the reactants. • The plasma swirler can be used alone or combine with other traditional swirlers.

  20. Characterization of Plasma Flow through Magnetic Nozzles

    Science.gov (United States)

    1990-02-01

    rovisional models are utilized to estimate the thermal transport. Filially , with regard to radiation losses over the range of parameters considered...i.nle itse-if, A amore ctmupelt physic. ldescript iti n requilre.S the Solutionl of thle etuimiionls of radiative t ralisier withidmi he flow filold, and...imbeddted ila no71le wihout q-w iug he st eady flow of phaslna. Filially , we shll (iscuss the gel eral proldeil of findtitg- II eqIilibr n wit II difie I

  1. Plasma action on helium flow in cold atmospheric pressure plasma jet experiments

    Science.gov (United States)

    Darny, T.; Pouvesle, J.-M.; Fontane, J.; Joly, L.; Dozias, S.; Robert, E.

    2017-10-01

    In this work, helium flow modifications, visualized by schlieren imaging, induced by the plasma generated in a plasma jet have been studied in conditions used for biomedical treatments (jet being directed downwards with a low helium flow rate). It has been shown that the plasma action can shift up to few centimeters downstream the effects of buoyancy, which allows to the helium flow to reach a target below in conditions for which it is not the case when the plasma is off. This study reveals the critical role of large and long lifetime negative ions during repetitive operations in the kHz regime, inducing strong modifications in the gas propagation. The cumulative added streamwise momentum transferred to ambient air surrounding molecules resulting from a series of applied voltage pulses induces a gradual built up of a helium channel on tens of millisecond timescale. In some conditions, a remarkable stable cylindrical helium channel can be generated to the target with plasma supplied by negative polarity voltage pulses whereas a disturbed flow results from positive polarity operation. This has a direct effect on air penetration in the helium channel and then on the reactive species production over the target which is of great importance for biomedical applications. It has also been shown that with an appropriate combination of negative and positive polarity pulses, it is possible to benefit from both polarity features in order to optimize the plasma plume propagation and plasma delivery to a target.

  2. Optimization of plasma flow parameters of the magnetoplasma compressor

    Science.gov (United States)

    Dojcinovic, I. P.; Kuraica, M. M.; Obradovc, B. M.; Cvetanovic, N.; Puric, J.

    2007-02-01

    Optimization of the working conditions of the magnetoplasma compressor (MPC) has been performed through analysing discharge and compression plasma flow parameters in hydrogen, nitrogen and argon at different pressures. Energy conversion rate, volt-ampere curve exponent and plasma flow velocities have been studied to optimize the efficiency of energy transfer from the supply source to the plasma. It has been found that the most effective energy transfer from the supply to the plasma is in hydrogen as a working gas at 1000 Pa pressure. It was found that the accelerating regime exists for hydrogen up to 3000 Pa pressures, in nitrogen up to 2000 Pa and in argon up to 1000 Pa pressure. At higher pressures MPC in all the gases works in the decelerating regime. At pressures lower than 200 Pa, high cathode erosion is observed. MPC plasma flow parameter optimization is very important because this plasma accelerating system may be of special interest for solid surface modification and other technology applications.

  3. 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...

  4. Observation of plasma microwave emission during the injection of supersonic plasma flows into magnetic arch

    Science.gov (United States)

    Viktorov, Mikhail; Mansfeld, Dmitry; Vodopyanov, Alexander; Golubev, Sergey

    2017-10-01

    Understanding of the energy transfer mechanisms from supersonic plasma flow into the thermal energy of plasma, waves and accelerated particles in the environment of planetary bow shocks and interplanetary shocks have been topical for many decades. Almost all mechanisms of energy dissipation in collisionless shock waves end with microscopic processes involving wave-particle interactions. Excitation of plasma waves in electron cyclotron frequency range plays an important role in the dissipation of bulk flow energy across the Earth bow shock. In the present work, the process of plasma deceleration during the injection of supersonic plasma flow across the magnetic field of an arched configuration is experimentally demonstrated. Pulsed plasma microwave emission in the electron cyclotron frequency range is observed. It is shown that the frequency spectrum of plasma emission is determined by the position of the deceleration region in the magnetic field of the magnetic arc and its bandwidth is defined by the magnetic field inhomogeneity in the deceleration region. The observed emission can be related to the cyclotron mechanism of wave generation by non-equilibrium energetic electrons in the dense plasma, especially excitation of electron Bernstein waves. The work was supported by RFBR (Project No. 16-32-60056).

  5. Generation of zonal flows in rotating fluids and magnetized plasmas

    DEFF Research Database (Denmark)

    Juul Rasmussen, J.; Garcia, O.E.; Naulin, V.

    2006-01-01

    near the centre with low potential vorticity from the outside, which will imply the formation of a large-scale flow. The experimental results are supported by direct numerical solutions of the quasi-geostrophic vorticity equation in the beta-plane approximation modelling the experimental situation....... The analogy to large-scale flow generation in drift-wave turbulence dynamics in magnetized plasma is briefly discussed....

  6. MHD Simulations of the Plasma Flow in the Magnetic Nozzle

    Science.gov (United States)

    Smith, T. E. R.; Keidar, M.; Sankaran, K.; olzin, K. A.

    2013-01-01

    The magnetohydrodynamic (MHD) flow of plasma through a magnetic nozzle is simulated by solving the governing equations for the plasma flow in the presence of an static magnetic field representing the applied nozzle. This work will numerically investigate the flow and behavior of the plasma as the inlet plasma conditions and magnetic nozzle field strength are varied. The MHD simulations are useful for addressing issues such as plasma detachment and to can be used to gain insight into the physical processes present in plasma flows found in thrusters that use magnetic nozzles. In the model, the MHD equations for a plasma, with separate temperatures calculated for the electrons and ions, are integrated over a finite cell volume with flux through each face computed for each of the conserved variables (mass, momentum, magnetic flux, energy) [1]. Stokes theorem is used to convert the area integrals over the faces of each cell into line integrals around the boundaries of each face. The state of the plasma is described using models of the ionization level, ratio of specific heats, thermal conductivity, and plasma resistivity. Anisotropies in current conduction due to Hall effect are included, and the system is closed using a real-gas equation of state to describe the relationship between the plasma density, temperature, and pressure.A separate magnetostatic solver is used to calculate the applied magnetic field, which is assumed constant for these calculations. The total magnetic field is obtained through superposition of the solution for the applied magnetic field and the self-consistently computed induced magnetic fields that arise as the flowing plasma reacts to the presence of the applied field. A solution for the applied magnetic field is represented in Fig. 1 (from Ref. [2]), exhibiting the classic converging-diverging field pattern. Previous research was able to demonstrate effects such as back-emf at a super-Alfvenic flow, which significantly alters the shape of the

  7. Establishing isokinetic flow for a plasma torch exhaust gas diagnostic for a plasma hearth furnace

    Energy Technology Data Exchange (ETDEWEB)

    Pollack, Brian R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    1996-05-01

    Real time monitoring of toxic metallic effluents in confined gas streams can be accomplished through use of Microwave Induced Plasmas to perform atomic emission spectroscopy, For this diagnostic to be viable it is necessary that it sample from the flowstream of interest in an isokinetic manner. A method of isokinetic sampling was established for this device for use in the exhaust system of a plasma hearth vitrification furnace. The flow and entrained particulate environment were simulated in the laboratory setting using a variable flow duct of the same dimensions (8-inch diameter, schedule 40) as that in the field and was loaded with similar particulate (less than 10 μm in diameter) of lake bed soil typically used in the vitrification process. The flow from the furnace was assumed to be straight flow. To reproduce this effect a flow straightener was installed in the device. An isokinetic sampling train was designed to include the plasma torch, with microwave power input operating at 2.45 GHz, to match local freestream velocities between 800 and 2400 ft/sec. The isokinetic sampling system worked as planned and the plasma torch had no difficulty operating at the required flowrates. Simulation of the particulate suspension was also successful. Steady particle feeds were maintained over long periods of time and the plasma diagnostic responded as expected.

  8. Sensing and control of flow separation using plasma actuators.

    Science.gov (United States)

    Corke, Thomas C; Bowles, Patrick O; He, Chuan; Matlis, Eric H

    2011-04-13

    Single dielectric barrier discharge plasma actuators have been used to control flow separation in a large number of applications. An often used configuration involves spanwise-oriented asymmetric electrodes that are arranged to induce a tangential wall jet in the mean flow direction. For the best effect, the plasma actuator is placed just upstream of where the flow separation will occur. This approach is generally more effective when the plasma actuator is periodically pulsed at a frequency that scales with the streamwise length of the separation zone and the free-stream velocity. The optimum frequency produces two coherent spanwise vortices within the separation zone. It has been recently shown that this periodic pulsing of the plasma actuator could be sensed by a surface pressure sensor only when the boundary layer was about to separate, and therefore could provide a flow separation indicator that could be used for feedback control. The paper demonstrates this approach on an aerofoil that is slowly increasing its angle of attack, and on a sinusoidally pitching aerofoil undergoing dynamic stall. Short-time spectral analysis of time series from a static pressure sensor on the aerofoil is used to determine the separation state that ranges from attached, to imminent separation, to fully separated. A feedback control approach is then proposed, and demonstrated on the aerofoil with the slow angle of attack motion.

  9. Taylor-Dean flow on the Plasma Couette Experiment (PCX)

    Science.gov (United States)

    Flanagan, K.; Clark, M.; Collins, C.; Cooper, C.; Khalzov, I.; Wallace, J.; Forest, C.

    2014-10-01

    A Taylor-Dean flow profile is implemented on the upgraded Plasma Couette Experiment (PCX) aimed at exciting the magnetorotational instability (MRI). Taylor-Dean flow profiles are set up by injecting torque via a radial current crossing an axial magnetic field. A ``virtual cathode'' is set up in the center of PCX by applying a bias from a cathode located at the top center of the vessel to an anode at the bottom. This circuit is biased with respect to anodes at the outer wall to drive a radial current. A small vertical magnetic field is then applied via external Helmholtz coils in order to induce a J × B torque. Theoretical investigations have shown that the ion-neutral drag in PCX plasmas with low ionization fractions negatively affect the MRI threshold and growth rate. In order to increase the ionization fraction in PCX, upgrades to the multicusp magnet system and microwave power are underway. New SmCo magnets, like those used on the Madison Plasma Dynamo Experiment (MPDX), will provide better confinement and tolerate higher plasma temperatures than the previous ceramic ones. A MRI stability analysis of Taylor-Dean flows under relevant PCX parameters as well as early flow data will be presented.

  10. Plasma heating, electric fields and plasma flow by electron beam ionospheric injection

    Science.gov (United States)

    Winckler, J. R.; Erickson, K. N.

    1990-01-01

    The electric fields and the floating potentials of a Plasma Diagnostics Payload (PDP) located near a powerful electron beam injected from a large sounding rocket into the auroral zone ionosphere have been studied. As the PDP drifted away from the beam laterally, it surveyed a region of hot plasma extending nearly to 60 m radius. Large polarization electric fields transverse to B were imbedded in this hot plasma, which displayed large ELF wave variations and also an average pattern which has led to a model of the plasma flow about the negative line potential of the beam resembling a hydrodynamic vortex in a uniform flow field. Most of the present results are derived from the ECHO 6 sounding rocket mission.

  11. Configuration of Spontaneous Flows in a Plasma Coherent Structure

    Science.gov (United States)

    Hasegawa, Hiroki; Ishiguro, Seiji

    2013-10-01

    Spontaneous particle flows in a plasma coherent structure (blob) have been studied with a three dimensional electrostatic plasma particle simulation code. In the particle simulation, the particle absorbing boundaries are placed on the both ends in the z direction (corresponding to the toroidal direction) and one end in the x direction (corresponding to the counter radial direction). The former boundaries and the latter one corresponds to end plates (divertor plates) and the first wall. A coherent structure is initially set as a column along the external magnetic field and propagates to the first wall because the magnetic field is set as ∂B / ∂x ≠ 0 . In this study, we have investigated the configuration of spontaneous particle flows in a plasma coherent structure. We have found that a spiral current system in a plasma blob and characteristic features in the velocity distribution of plasma particles in a blob. Supported by NIFS Collaboration Research programs (NIFS13KNSS038 and NIFS13KNXN258) and a Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science (KAKENHI 23740411).

  12. Flow visualization in a low-density plasma channel

    Science.gov (United States)

    Kimmel, R. L.; Hayes, J. R.; Estevadeordal, J.; Crafton, J. W.; Fonov, S. D.; Gogineni, S.

    2010-04-01

    A schlieren system and surface-stress-sensitive film system were developed for a plasma channel which posed unique challenges for flow visualization because of the combination of low air density and the presence of plasma discharges. Temperature-sensitive paint and direct-current discharge were also applied to flow visualization. Three pulsed schlieren light sources were evaluated. A light-emitting diode (LED), a xenon NanopulserTM and laser breakdown, were tested on identical flowfields. The LED provided excellent illumination, with pulses ranging from μs to continuous. The NanopulserTM provided excellent, short-duration images, although illumination varied from shot-to-shot. Laser-breakdown provided short-duration, incoherent illumination that was constant from pulse-to-pulse. The surface-stress-sensitive film was applied to surface flow visualization. A low-modulus elastomer doped with a luminescent dye was used to visualize the surface shear stress and pressure field in laminar shock boundary layer interactions. Intensity distributions from the dye were imaged to interrogate the surface pressure gradients. Displacement of surface markers provided shear information. Results showed the presence of Görtler vortices in the reattaching shear flow. Görtler vortices were also evident in temperature-sensitive paint images and in the plasma discharge glow. These vortices were evident in the intensity images from the elastomer, which could be related to the surface pressure gradient, but were not readily evident in surface shear measurements.

  13. Relation of plasma flow structures to passive particle tracer orbits

    Science.gov (United States)

    García, L.; Carreras, B. A.; Llerena, I.

    2017-11-01

    The properties of plasma flow topological structures are compared with those of passive tracer particles within a framework of the continuous random walk (CTRW) approach. Vortices may cause some of the trapping of particles, while large scale flows may carry them from vortex to vortex. The results indicate that most of the trappings that are completed during the calculation correspond to tracers trapped on broken filaments, including possible multiple trappings. The probability distribution function of the trapping times is then a function of the filament length, and has a lognormal character, like the distribution of filament lengths.

  14. Zonal flow excitation by drift waves in toroidal plasmas

    Energy Technology Data Exchange (ETDEWEB)

    L Chen; Z. Lin; R. White

    2000-06-13

    Recent 3D gyrokinetic and gyrofluid simulations in toroidal plasmas have demonstrated that zonal flows play a crucial role in regulating the nonlinear evolution of electrostatic drift-wave instabilities such as the ion temperature gradient (ITG) modes and, as a consequence, the level of the anomalous ion thermal transport, and that zonal flows could be spontaneously excited by ITG turbulence, suggesting parametric instability processes as the generation mechanism. Diamond et. al. have proposed the modulational instability of drift-wave turbulence ( plasmons ) in a slab-geometry treatment.

  15. Magnetic field-aligned electric potentials in nonideal plasma flows

    Science.gov (United States)

    Schindler, K.; Hesse, M.; Birn, J.

    1991-01-01

    The electric field component parallel to the magnetic field arising from plasma flows which violate the frozen-in field condition of ideal magnetohydrodynamics is discussed. The quantity of interest is the potential U = integral E parallel ds where the integral is extended along field lines. It is shown that U can be directly related to magnetic field properties, expressed by Euler potentials, even when time-dependence is included. These results are applicable to earth's magnetosphere, to solar flares, to aligned-rotator models of compact objects, and to galactic rotation. On the basis of order-of-magnitude estimates, these results support the view that parallel electric fields associated with nonideal plasma flows might play an important role in cosmic particle acceleration.

  16. Kinetic effects and reversal flows in the tokamak edge plasma

    Energy Technology Data Exchange (ETDEWEB)

    Krasheninnikov, S.I.; Soboleva, T.K. (Russian Scientific Center, Kurchatov Inst., Moscow (Russia)); Batischev, O.V.; Zmievskaya, G.I.; Levchenko, V.D.; Ovchenkov, P.A.; Sigov, Yu.S.; Silaev, I.I. (M.V. Keldysh Inst. of Applied Mathematics, Russian Academy of Science, Moscow (Russia))

    1992-12-01

    Preliminary results of the edge tokamak plasma simulation in the frame of 3D kinetic Vlasov-Fokker-Planck equations are presented. Currently two versions of the code are developed: One of them is based on a stochastic modeling method, another uses a finite difference approach via split techniques. In both versions, the self-consistent electric field may be calculated from the quasi-neutrality condition, while the sheath potential is obtained from the ambipolarity of plasma flux towards the neutralizing plate. Simplified equations, describing the dense SOL plasma parameters distributions and allowing the analytical solutions are obtained. It is shown, that for the high particle recycling in SOL, the radial scales of the temperature [Delta][sub T] and densities, [Delta][sub n] are close to each other. The reversal flow is formed within a narrow layer near the separatrix magnetic surface. (orig.).

  17. Thermonuclear dynamo inside ultracentrifuge with supersonic plasma flow stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Winterberg, F. [University of Nevada, Reno, Reno, Nevada (United States)

    2016-01-15

    Einstein's general theory of relativity implies the existence of virtual negative masses in the rotational reference frame of an ultracentrifuge with the negative mass density of the same order of magnitude as the positive mass density of a neutron star. In an ultracentrifuge, the repulsive gravitational field of this negative mass can simulate the attractive positive mass of a mini-neutron star, and for this reason can radially confine a dense thermonuclear plasma placed inside the centrifuge, very much as the positive mass of a star confines its plasma by its own attractive gravitational field. If the centrifuge is placed in an externally magnetic field to act as the seed field of a magnetohydrodynamic generator, the configuration resembles a magnetar driven by the release of energy through nuclear fusion, accelerating the plasma to supersonic velocities, with the magnetic field produced by the thermomagnetic Nernst effect insulating the hot plasma from the cold wall of the centrifuge. Because of the supersonic flow and the high plasma density the configuration is stable.

  18. Banning the Bottle

    Science.gov (United States)

    Palliser, Janna

    2010-01-01

    Bottled water is ubiquitous, taken for granted, and seemingly benign. Americans are consuming bottled water in massive amounts and spending a lot of money: In 2007, Americans spent $11.7 billion on 8.8 billions gallons of bottled water (Gashler 2008). That same year, two million plastic water bottles were used in the United States every five…

  19. Flow cytometric immunophenotypic characteristics of plasma cell leukemia

    Directory of Open Access Journals (Sweden)

    Barbara Kruk

    2011-04-01

    Full Text Available The aim of this prospective study was to define the flow cytometric characteristics of simultaneously investigated bone marrow and peripheral blood plasma cells antigens expression in 36 plasma cell leukemia (PCL patients. The immunophenotypic profile of plasma cells was determined with a panel of monoclonal antibodies. The antigen expression intensity was calculated as relative fluorescence intensity (RFI. Bone marrow plasma cells showed expression of particular antigens in the following proportion of cases: CD49d 100%, CD29 94%, CD54 93%, CD44 83%, CD56 60%, CD18 26%, CD11b 29%, CD11a 19%, CD117 27%, CD71 30%, CD126 100% and CD19 0%, while the expression of those antigens on peripheral blood plasma cells was present in the following percentage of patients: CD49d 100%, CD29 96%, CD54 93%, CD44 95%, CD56 56%, CD18 50%, CD11b 53%, CD11a 29%, CD117 26%, CD71 28%, CD126 100% and CD19 0%. The expression of CD54 was significantly higher than that of adhesion molecules belonging to the integrin b2 family: CD11a, CD18 and CD11b, on both bone marrow and peripheral blood cells (p < 0.01. Expression of CD18, CD11a and CD11b was differential between two cell compartments: lower on bone marrow and higher on peripheral blood cells. We found that plasma cells in the bone marrow of patients with plasma cell leukaemia showed significantly greater granularity and size than those in the peripheral blood (p = 0.0001 and p = 0.04, respectively. However, no differences in cell size or granularity were revealed between bone marrow plasma cells from patients with PCL and multiple myeloma. In conclusion, impaired expression of adhesion molecules such as CD11a/CD18 (LFA-1 or CD56 may explain hematogenic dissemination characterizing PCL. The following pattern of adhesion molecule expression according to the proportion of plasma cells expressing a given antigen in peripheral blood and bone marrow and arranged in diminishing order may be established: CD49d > CD44 > CD54

  20. Critical gradients and plasma flows in the edge plasma of Alcator C-Moda)

    Science.gov (United States)

    Labombard, B.; Hughes, J. W.; Smick, N.; Graf, A.; Marr, K.; McDermott, R.; Reinke, M.; Greenwald, M.; Lipschultz, B.; Terry, J. L.; Whyte, D. G.; Zweben, S. J.; Alcator C-Mod Team

    2008-05-01

    Recent experiments have led to a fundamental shift in our view of edge transport physics; transport near the last-closed flux surface may be more appropriately described in terms of a critical gradient phenomenon rather than a diffusive and/or convective paradigm. Edge pressure gradients, normalized by the square of the poloidal magnetic field strength, appear invariant in plasmas with the same normalized collisionality, despite vastly different currents and magnetic fields—a behavior that connects with first-principles electromagnetic plasma turbulence simulations. Near-sonic scrape-off layer (SOL) flows impose a cocurrent rotation boundary condition on the confined plasma when B ×∇B points toward the active x-point, suggesting a link to the concomitant reduction in input power needed to attain high-confinement modes. Indeed, low-confinement mode plasmas are found to attain higher edge pressure gradients in this configuration, independent of the direction of B, evidence that SOL flows may affect transport and "critical gradient" values in the edge plasma.

  1. Dielectric barrier discharge plasma actuator for flow control

    Science.gov (United States)

    Opaits, Dmitry Florievich

    Electrohydrodynamic (EHD) and magnetohydrodynamic phenomena are being widely studied for aerodynamic applications. The major effects of these phenomena are heating of the gas, body force generation, and enthalpy addition or extraction, [1, 2, 3]. In particular, asymmetric dielectric barrier discharge (DBD) plasma actuators are known to be effective EHD device in aerodynamic control, [4, 5]. Experiments have demonstrated their effectiveness in separation control, acoustic noise reduction, and other aeronautic applications. In contrast to conventional DBD actuators driven by sinusoidal voltages, we proposed and used a voltage profile consisting of nanosecond pulses superimposed on dc bias voltage. This produces what is essentially a non-self-sustained discharge: the plasma is generated by repetitive short pulses, and the pushing of the gas occurs primarily due to the bias voltage. The advantage of this non-self-sustained discharge is that the parameters of ionizing pulses and the driving bias voltage can be varied independently, which adds flexibility to control and optimization of the actuators performance. Experimental studies were conducted of a flow induced in a quiescent room air by a single DBD actuator. A new approach for non-intrusive diagnostics of plasma actuator induced flows in quiescent gas was proposed, consisting of three elements coupled together: the Schlieren technique, burst mode of plasma actuator operation, and 2-D numerical fluid modeling. During the experiments, it was found that DBD performance is severely limited by surface charge accumulation on the dielectric. Several ways to mitigate the surface charge were found: using a reversing DC bias potential, three-electrode configuration, slightly conductive dielectrics, and semi conductive coatings. Force balance measurements proved the effectiveness of the suggested configurations and advantages of the new voltage profile (pulses+bias) over the traditional sinusoidal one at relatively low

  2. Estimation of Flow Channel Parameters for Flowing Gas Mixed with Air in Atmospheric-pressure Plasma Jets

    Science.gov (United States)

    Yambe, Kiyoyuki; Saito, Hidetoshi

    2017-12-01

    When the working gas of an atmospheric-pressure non-equilibrium (cold) plasma flows into free space, the diameter of the resulting flow channel changes continuously. The shape of the channel is observed through the light emitted by the working gas of the atmospheric-pressure plasma. When the plasma jet forms a conical shape, the diameter of the cylindrical shape, which approximates the conical shape, defines the diameter of the flow channel. When the working gas flows into the atmosphere from the inside of a quartz tube, the gas mixes with air. The molar ratio of the working gas and air is estimated from the corresponding volume ratio through the relationship between the diameter of the cylindrical plasma channel and the inner diameter of the quartz tube. The Reynolds number is calculated from the kinematic viscosity of the mixed gas and the molar ratio. The gas flow rates for the upper limit of laminar flow and the lower limit of turbulent flow are determined by the corresponding Reynolds numbers estimated from the molar ratio. It is confirmed that the plasma jet length and the internal plasma length associated with strong light emission increase with the increasing gas flow rate until the rate for the upper limit of laminar flow and the lower limit of turbulent flow, respectively. Thus, we are able to explain the increasing trend in the plasma lengths with the diameter of the flow channel and the molar ratio by using the cylindrical approximation.

  3. Magnetized plasma flow injection into tokamak and high-beta compact torus plasmas

    Science.gov (United States)

    Matsunaga, Hiroyuki; Komoriya, Yuuki; Tazawa, Hiroyasu; Asai, Tomohiko; Takahashi, Tsutomu; Steinhauer, Loren; Itagaki, Hirotomo; Onchi, Takumi; Hirose, Akira

    2010-11-01

    As an application of a magnetized coaxial plasma gun (MCPG), magnetic helicity injection via injection of a highly elongated compact torus (magnetized plasma flow: MPF) has been conducted on both tokamak and field-reversed configuration (FRC) plasmas. The injected plasmoid has significant amounts of helicity and particle contents and has been proposed as a fueling and a current drive method for various torus systems. In the FRC, MPF is expected to generate partially spherical tokamak like FRC equilibrium by injecting a significant amount of magnetic helicity. As a circumstantial evidence of the modified equilibrium, suppressed rotational instability with toroidal mode number n = 2. MPF injection experiments have also been applied to the STOR-M tokamak as a start-up and current drive method. Differences in the responses of targets especially relation with beta value and the self-organization feature will be studied.

  4. Experiments on planar plasma flow switches at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Benage, J.F. Jr.; Wysocki, F.J.; Bowers, R.; Oona, H. [and others

    1997-12-01

    The authors have performed a series of experiments on the Colt facility at Los Alamos to study the performance of plasma flow switches and to understand the important physics issues which affect that performance. These experiments were done in planar geometry on a small machine to allow for better diagnostic access and a higher repetition rate. The Colt facility is a capacitor bank which stores 300 kJ at maximum charge and produced a peak current of 1.1 MA in 2.0 microseconds for these experiments. The diagnostics used for these experiments included an array of b-dot probes, visible framing pictures, visible spectroscopy, and laser interferometry. Characteristics of the switch are determined from spatial and temporal profiles of the magnetic field and the spatial profile and temperature of the switch plasma. Here the authors present results from experiments for a variety of switch conditions.

  5. On the generation of field-aligned plasma flow at the boundary of the plasma sheet

    Science.gov (United States)

    Schindler, K.; Birn, J.

    1987-01-01

    A possible cause of the large plasma flow velocities parallel to the magnetic field (which were observed in spacecraft experiments) near the boundary of the plasma sheet in the earth's magnetotail is considered in the framework of a magnetohydrodynamic model. It is shown for steady-state configurations that high parallel flow velocities can be expected to exist on field lines connecting to a region of weak magnetic field. The physical mechanism causing large values of the parallel velocity component can be visualized as a strong imbalance of perpendicular mass flux into and out of magnetic flux tubes passing through regions where the magnetic field is weak and inhomogeneous. The value of the parallel velocity component is evaluated, and it is found that it can substantially exceed the perpendicular velocity (by as much as a factor of 40). The results are applied to the earth's magnetotail; it is found that this mechanism is able to explain the parallel flow velocities near the boundary of the plasma sheet in the range of several hundreds of km/s.

  6. INTERACTIONS OF FLOWING PLASMA WITH COLLECTING SPHERE/OBJECTS

    Energy Technology Data Exchange (ETDEWEB)

    HUTCHINSON, IAN H.

    2013-10-31

    The proposer’s computational flowing plasma group, supported in part by NSF/DOE since 2006, has been enormously productive. It has published 22 journal articles, of which 3 are in Physical Review Letters; received a total of 330 citations, and made 5 invited and numerous contributed presentations at international conferences. In addition, other groups have published at least 3 papers [20-22] based upon results they have obtained from the SCEPTIC code, developed by the proposer. The codes developed for this subject are Particle In Cell (PIC) codes, representing the entire ion distribution function and its variation in space in the vicinity of an absorbing object.

  7. Plasma equilibria and stationary flows in axisymmetric systems. Pt. 3

    Energy Technology Data Exchange (ETDEWEB)

    Zelazny, R.; Stankiewicz, R.; Galkowski, A.; Potempski, S.; Pietak, R.

    1990-08-01

    The problem of the importance of poloidal flows for the behaviour of plasmas in axisymmetric systems has caused a lot of discussion and controversy during the last 15 years. There is no doubt that the mere existence of poloidal flow transforms the elliptic Grad-Shafranov-Schlueter equation into a system of mixed type partial differential equation and an algebraic multivalued Bernoulli equation. This fact leads to the appearance of Bernoulli branches in the solutions. Then, one can come across three branches of elliptic solutions as well as two branches of hyperbolic solutions with the possible appearance of phenomena connected with ``transsonic`` effects. Problems connected with such a mathematical situation have been extensively discussed in the report with the same title, dated May 1988, which we shall call later Part I of our studies on this subject. The present report, considered as Part III, is devoted to the presentation of results of efforts aimed at constructing programmes which allow us to solve the extended Grad-Shafranov-Schlueter equation (EGSS) (with stationary flows) in a more realistic situation relevant to the JET operating conditions. The main problem is to specify for a wider class of profiles the boundary conditions at the magnetic axis for a system of nonlinear ordinary differential equations ODE, resulting from EGSS equation after application of Fourier transformation techniques and of inverse method approach. The present report elaborates a much more general case and describes the computational framework enabling us to derive those boundary conditions. (author).

  8. Neoclassical flows in deuterium-helium plasma density pedestals

    CERN Document Server

    Buller, Stefan; Newton, Sarah; Omotani, John

    2016-01-01

    In tokamak transport barriers, the radial scale of profile variations can be comparable to a typical ion orbit width, which makes the coupling of the distribution function across flux surfaces important in the collisional dynamics. We use the radially global steady-state neoclassical {\\delta}f code Perfect to calculate poloidal and toroidal flows, and radial fluxes, in the pedestal. In particular, we have studied the changes in these quantities as the plasma composition is changed from a deuterium bulk species with a helium impurity to a helium bulk with a deuterium impurity, under specific profile similarity assumptions. The poloidally resolved radial fluxes are not divergence-free in isolation in the presence of sharp radial profile variations, which leads to the appearance of poloidal return-flows. These flows exhibit a complex radial-poloidal structure that extends several orbit widths into the core and is sensitive to abrupt radial changes in the ion temperature gradient. We find that a sizable neoclassi...

  9. Driving large magnetic Reynolds number flow in highly ionized, unmagnetized plasmas

    Science.gov (United States)

    Weisberg, D. B.; Peterson, E.; Milhone, J.; Endrizzi, D.; Cooper, C.; Désangles, V.; Khalzov, I.; Siller, R.; Forest, C. B.

    2017-05-01

    Electrically driven, unmagnetized plasma flows have been generated in the Madison plasma dynamo experiment with magnetic Reynolds numbers exceeding the predicted Rmcrit = 200 threshold for flow-driven MHD instability excitation. The plasma flow is driven using ten thermally emissive lanthanum hexaboride cathodes which generate a J ×B torque in helium and argon plasmas. Detailed Mach probe measurements of plasma velocity for two flow topologies are presented: edge-localized drive using the multi-cusp boundary field and volumetric drive using an axial Helmholtz field. Radial velocity profiles show that the edge-driven flow is established via ion viscosity but is limited by a volumetric neutral drag force, and measurements of velocity shear compare favorably to the Braginskii transport theory. Volumetric flow drive is shown to produce larger velocity shear and has the correct flow profile for studying the magnetorotational instability.

  10. Stopping the Bottle

    Science.gov (United States)

    ... is coming later. The next week, eliminate another bottle feeding and provide milk in a cup instead. Try to do this when your baby is sitting at the table in a high chair. Generally, the last bottle to stop should be the nighttime bottle. That ...

  11. Green Fiber Bottle

    DEFF Research Database (Denmark)

    Didone, Mattia; Tosello, Guido

    The ambition of the Green Fiber Bottle (GFB) project is to manufacture a fully biodegradable bottle. Carlsberg is the intended end user, and they aim to package their beer in the new bottle. The new product is intended to replace the existing plastic and glass bottles, and thus reducing their imp......The ambition of the Green Fiber Bottle (GFB) project is to manufacture a fully biodegradable bottle. Carlsberg is the intended end user, and they aim to package their beer in the new bottle. The new product is intended to replace the existing plastic and glass bottles, and thus reducing...... their impact on the environment, especially the oceans. For example, the life span of a plastic bottle in the ocean is 500 years, and during its degradation, the plastic is reduced to micro pieces, which causes the starvation of several marine animals. The new bottle is completely made from molded paper pulp......, which is a renewable resource. Nevertheless, due to food and drugs limitations, only virgin paper fibers must be employed in the production. The bottle could then be left to biodegrade in nature or enter a recycle system, along with other paper-based product. In order to contain the liquid, the bottle...

  12. Bisphenol A determination in baby bottles by chemiluminescence enzyme-linked immunosorbent assay, lateral flow immunoassay and liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Maiolini, Elisabetta; Ferri, Elida; Pitasi, Agata Laura; Montoya, Angel; Di Giovanni, Manuela; Errani, Ermanno; Girotti, Stefano

    2014-01-07

    Two immunoassays, a Lateral Flow ImmunoAssay (LFIA) based on colloidal gold nanoparticle labels and an indirect competitive chemiluminescence enzyme-linked immunosorbent assay (CL-ELISA), were developed and a high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was optimized to assess the possible release of bisphenol A (BPA, 4,4'-isopropylidenediphenol) from different plastic baby bottles treated with simulating solutions. Coating conjugate concentration, anti-BPA antibody dilution, incubation time of the primary and secondary antibodies, and tolerance to different organic solvents were optimized to obtain the best performance of the ELISA with chemiluminescent end-point detection. The influence of different buffers on LFIA performance was also evaluated. Both methods showed good repeatability (mean CV value around 13%) and sensitivity. Reproducibility tests for CL-ELISA gave a mean CV value of about 25%. The IC50 and Limit of Detection (LOD) values of CL-ELISA were 0.2 and 0.02 ng mL(-1), respectively. The LOD of LFIA was 0.1 μg mL(-1). A LC-MS/MS method was also optimized. The separation was performed in a C18 column with a triple-quadrupole mass spectrometer with electrospray ionisation interface. The method showed a good linearity in the range 2 to 500 ng mL(-1), with a regression coefficient of 0.998. In the simulating solutions the detection and quantification limits, calculated by the signal to noise level of 3 (S/N = 3), were 5.8 ng mL(-1) and 17.4 ng mL(-1), respectively. This limit of quantification was about 3 and 35 times lower than the permitted limits set by the official method CEN/TS 13130-13 (0.05 μg mL(-1)) and by the Directive 2004/19/EC (0.6 μg mL(-1)), respectively. The methods were applied to determine BPA release from baby bottles, performing repeated procedures according to EU and national regulations. The results demonstrated that no BPA migration from the tested plastic materials occurred with only one

  13. FLOCK cluster analysis of plasma cell flow cytometry data predicts bone marrow involvement by plasma cell neoplasia.

    Science.gov (United States)

    Dorfman, David M; LaPlante, Charlotte D; Li, Betty

    2016-09-01

    We analyzed plasma cell populations in bone marrow samples from 353 patients with possible bone marrow involvement by a plasma cell neoplasm, using FLOCK (FLOw Clustering without K), an unbiased, automated, computational approach to identify cell subsets in multidimensional flow cytometry data. FLOCK identified discrete plasma cell populations in the majority of bone marrow specimens found by standard histologic and immunophenotypic criteria to be involved by a plasma cell neoplasm (202/208 cases; 97%), including 34 cases that were negative by standard flow cytometric analysis that included clonality assessment. FLOCK identified discrete plasma cell populations in only a minority of cases negative for involvement by a plasma cell neoplasm by standard histologic and immunophenotypic criteria (38/145 cases; 26%). Interestingly, 55% of the cases negative by standard analysis, but containing a FLOCK-identified discrete plasma cell population, were positive for monoclonal gammopathy by serum protein electrophoresis and immunofixation. FLOCK-identified and quantitated plasma cell populations accounted for 3.05% of total cells on average in cases positive for involvement by a plasma cell neoplasm by standard histologic and immunophenotypic criteria, and 0.27% of total cells on average in cases negative for involvement by a plasma cell neoplasm by standard histologic and immunophenotypic criteria (pflow cytometric analysis, and had specificity of 74%, PPV of 84% and NPV of 95%. FLOCK analysis, which has been shown to provide useful diagnostic information for evaluating patients with suspected systemic mastocytosis, is able to identify neoplastic plasma cell populations analyzed by flow cytometry, and may be helpful in the diagnostic evaluation of bone marrow samples for involvement by plasma cell neoplasia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Calculation of the dynamics of compression plasma flows in a magnetoplasma compressor operating on air

    Science.gov (United States)

    Ananin, S. I.

    1986-03-01

    A two-dimensional model for describing the dynamics of partially ionized air compression plasma flows, generated by a magnetoplasma compressor, is proposed. The model is based on the large-particle method together with the introduction of a magnetic field. The results of calculations of the dynamics and structure of compression plasma flows are studied and compared with experimental data.

  15. Calculation of the dynamics of compression plasma flows in a magnetoplasma compressor operating on air

    Energy Technology Data Exchange (ETDEWEB)

    Ananin, S.I.

    1986-03-01

    This paper presents a two-dimensional model for describing the dynamics of partially ionized air compression plasma flows, generated by a magnetoplasma compressor. The model is based on the large-particle method together with the introduction of a magnetic field. The results of calculations of the dynamics and structure of compression plasma flows are studied and compared with experimental data.

  16. Experimental Investigation of Laser-sustained Plasma in Supersonic Argon Flow

    Science.gov (United States)

    Sperber, David; Eckel, Hans-Albert; Moessinger, Peter; Fasoulas, Stefanos

    2011-11-01

    Laser-induced energy deposition is widely discussed as a flow control technique in supersonic transportation. In case of thermal laser-plasma upstream of a blunt body, a substantial adaptation of shock wave geometry and magnitude of wave drag is predicted. Related to the research on laser supported detonation, the paper describes the implementation of laser-sustained plasma in a supersonic Argon jet. The stable plasma state is generated by the intersection of a Q-switched Nd:YAG-laser and a continuous wave CO2-laser beams, for ignition and maintenance of the plasma respectively. A miniature supersonic Ludwieg tube test facility generates a supersonic jet at velocities of Mach 2.1. Modifications of the flow and plasma conditions are investigated and characterized by Schlieren flow visualisation, laser energy transmission and plasma radiation measurements. The results include the discussions of the flow field as well as the required laser and gas parameters.

  17. Numerical simulation of the argon-hydrogen plasma flow in the channel of RF inductively coupled plasma torch

    Science.gov (United States)

    Grishin, Yu. M.; Long, Miao

    2017-11-01

    The results of numerical simulation of plasma flow in the channel of technological radio frequency (RF) plasma torch with three coils and frequency at 3 MHz are presented. The mixture of argon with hydrogen is considered as the working gas at a variation of hydrogen volume fraction α from 0 to 10%. The distributions of electromagnetic fields and gas-dynamic parameters of the plasma flow are calculated. It is shown that when the amplitude of discharge current exceeds the critical value Jcr (depends on α), the regime of plasma flow transforms from the potential to vortical regime, in which a toroidal vortex is formed before or in the inductor zone. The dependence of the values of the critical current Jcr on the volume concentration of hydrogen α is established. The influences of volume fraction α and discharge current Jcoil on the intensities and the position of the vortex center are determined.

  18. Increasing Plasma Parameters using Sheared Flow Stabilization of a Z-Pinch

    Science.gov (United States)

    Shumlak, Uri

    2016-10-01

    Recent experiments on the ZaP Flow Z-Pinch at the University of Washington have been successful in compressing the plasma column to smaller radii, producing the predicted increases in plasma density (1018 cm-3), temperature (200 eV), and magnetic fields (4 T), while maintaining plasma stability for many Alfven times (over 40 μs) using sheared plasma flows. These results indicate the suitability of the device as a discovery science platform for astrophysical and high energy density plasma research, and keeps open a possible path to achieving burning plasma conditions in a compact fusion device. Long-lived Z-pinch plasmas have been produced with dimensions of 1 cm radius and 100 cm long that are stabilized by sheared axial flows for over 1000 Alfven radial transit times. The observed plasma stability is coincident with the presence of a sheared flow as measured by time-resolved multi-chord ion Doppler spectroscopy applied to impurity ion radiation. These measurements yield insights into the evolution of the velocity profile and show that the stabilizing behavior of flow shear agrees with theoretical calculations and 2-D MHD computational simulations. The flow shear value, extent, and duration are shown to be consistent with theoretical models of the plasma viscosity, which places a design constraint on the maximum axial length of a sheared flow stabilized Z-pinch. Measurements of the magnetic field topology indicate simultaneous azimuthal symmetry and axial uniformity along the entire 100 cm length of the Z-pinch plasma. Separate control of plasma acceleration and compression have increased the accessible plasma parameters and have generated stable plasmas with radii below 0.5 cm, as measured with a high resolution digital holographic interferometer. This work was supported by Grants from U.S. DOE, NNSA, and ARPA-E.

  19. Effect of fractional blood flow on plasma skimming in the microvasculature

    Science.gov (United States)

    Yang, Jiho; Yoo, Sung Sic; Lee, Tae-Rin

    2017-04-01

    Although redistribution of red blood cells at bifurcated vessels is highly dependent on flow rate, it is still challenging to quantitatively express the dependence of flow rate in plasma skimming due to nonlinear cellular interactions. We suggest a plasma skimming model that can involve the effect of fractional blood flow at each bifurcation point. To validate the model, it is compared with in vivo data at single bifurcation points, as well as microvascular network systems. In the simulation results, the exponential decay of the plasma skimming parameter M along fractional flow rate shows the best performance in both cases.

  20. A Compact Plasma Flow-Bubbler for Decomposition of Organic compounds and Sterilization

    Science.gov (United States)

    Yoshiki, Hiroyuki; Ishikawa, Fukuto; Igarashi, Yu; Sugawara, Tetuya

    2015-09-01

    Recently, Plasma production in and in contact with liquid has attracted much attention because of their applications to degradation of organic compounds, sterilization, water purification. UV, electron, ion and radical flows originated from a plasma and also shock wave induce physical and chemical reaction in a liquid, for example oxidation-reduction, electrolysis and reactive species production in a water. In particular, various reactive oxygen/nitrogen species generated at the plasma-liquid interface play an important role in oxidation and degradation of organic pollutants and bacteria. We have proposed the mild water treatment by ejecting the atmospheric-pressure μ plasma (AP μP) flow into a water using a microbubble aerator or a porous ceramics bubbler. In this study, a compact plasma flow-bubbler made up of a μplasma source and a porous ceramics has been developed for the applications of water purification and sterilization. AP μP is generated between a thin metal pipe electrode and a GND plate by a pulsed high voltage, so that the O2 μ plasma can be obtained without adding He and Ar gases. Plasma flow is ejected into the water through a porous ceramics. Decolorization of an indigo carmine solution strongly depended on O2 flow rate. Chemical probe method using terephthalic acid revealed that OH radicals are produced by the O2 plasma gas bubbling. The inactivation for E. coli, Bacillus subtilis was attained by the O2 plasma gas bubbling.

  1. Dynamics of the interaction between plasma flows generated by a miniature magnetoplasma compressor and a target

    Science.gov (United States)

    Astashynski, V. M.; Kuzmitski, A. M.; Mishchuk, A. A.

    2011-07-01

    Spectroscopic studies of compression plasma flows generated by a miniature magnetoplasma compressor and of the shock compressed plasma layer formed near a target surface exposed to these flows are reported. The peak electron temperature and density are found to be 3 eV and 1.2ṡ1016 cm-3, respectively, in the compressor flow and 4.5 eV and 6.7ṡ1016 cm-3 in the shock compressed layer.

  2. WHATS-3: An Improved Flow-Through Multi-bottle Fluid Sampler for Deep-Sea Geofluid Research

    Directory of Open Access Journals (Sweden)

    Junichi Miyazaki

    2017-06-01

    Full Text Available Deep-sea geofluid systems, such as hydrothermal vents and cold seeps, are key to understanding subseafloor environments of Earth. Fluid chemistry, especially, provides crucial information toward elucidating the physical, chemical, and biological processes that occur in these ecosystems. To accurately assess fluid and gas properties of deep-sea geofluids, well-designed pressure-tight fluid samplers are indispensable and as such they are important assets of deep-sea geofluid research. Here, the development of a new flow-through, pressure-tight fluid sampler capable of four independent sampling events (two subsamples for liquid and gas analyses from each is reported. This new sampler, named WHATS-3, is a new addition to the WHATS-series samplers and a major upgrade from the previous WHATS-2 sampler with improvements in sample number, valve operational time, physical robustness, and ease of maintenance. Routine laboratory-based pressure tests proved that it is suitable for operation up to 35 MPa pressure. Successful field tests of the new sampler were also carried out in five hydrothermal fields, two in Indian Ocean, and three in Okinawa Trough (max. depth 3,300 m. Relations of Mg and major ion species demonstrated bimodal mixing trends between a hydrothermal fluid and seawater, confirming the high quality of fluids sampled. The newly developed WHATS-3 sampler is well-balanced in sampling capability, field usability, and maintenance feasibility, and can serve as one of the best geofluid samplers available at present to conduct efficient research of deep-sea geofluid systems.

  3. WHATS-3: An improved flow-through multi-bottle fluid sampler for deep-sea geofluid research

    Science.gov (United States)

    Miyazaki, Junichi; Makabe, Akiko; Matsui, Yohei; Ebina, Naoya; Tsutsumi, Saki; Ishibashi, Jun-ichiro; Chen, Chong; Kaneko, Sho; Takai, Ken; Kawagucci, Shinsuke

    2017-06-01

    Deep-sea geofluid systems, such as hydrothermal vents and cold seeps, are key to understanding subseafloor environments of Earth. Fluid chemistry, especially, provides crucial information towards elucidating the physical, chemical and biological processes that occur in these ecosystems. To accurately assess fluid and gas properties of deep-sea geofluids, well-designed pressure-tight fluid samplers are indispensable and as such they are important assets of deep-sea geofluid research. Here, the development of a new flow-through, pressure-tight fluid sampler capable of four independent sampling events (two subsamples for liquid and gas analyses from each) is reported. This new sampler, named WHATS-3, is a new addition to the WHATS-series samplers and a major upgrade from the previous WHATS-2 sampler with improvements in sample number, valve operational time, physical robustness, and ease of maintenance. Routine laboratory-based pressure tests proved that it is suitable for operation up to 35 MPa pressure. Successful field tests of the new sampler were also carried out in five hydrothermal fields, two in Indian Ocean and three in Okinawa Trough (max. depth 3,300 m). Relations of Mg and major ion species demonstrated bimodal mixing trends between a hydrothermal fluid and seawater, confirming the high-quality of fluids sampled. The newly developed WHATS-3 sampler is well-balanced in sampling capability, field usability, and maintenance feasibility, and can serve as one of the best geofluid samplers available at present to conduct efficient research of deep-sea geofluid systems.

  4. Studies of Plasma Flow Past Jupiter's Galilean Satellites

    Science.gov (United States)

    Linker, Jon A.

    2001-01-01

    We have investigated the interaction of Io, Jupiter's innermost Galilean satellite, with the Io plasma torus, using our semi-implicit time-dependent 3D MHD code to model the plasma interactions. We have used the same code to model the plasma interaction at Ganymede.

  5. Modulating toroidal flow stabilization of edge localized modes with plasma density

    CERN Document Server

    Cheng, Shikui; Banerjee, Debabrata

    2016-01-01

    Recent EAST experiments have demonstrated mitigation and suppression of edge localized modes (ELMs) with toroidal rotation flow in higher collisionality regime, suggesting potential roles of plasma density. In this work, the effects of plasma density on the toroidal flow stabilization of the high-$n$ edge localized modes have been extensively studied in linear calculations for a circular-shaped limiter H-mode tokamak, using the extended MHD code NIMROD. In the single MHD model, toroidal flow has a weak stabilizing effects on the high-$n$ modes. Such a stabilization, however, can be significantly enhanced with the increase in plasma density. Furthermore, our calculations show that the enhanced stabilization of high-$n$ modes from toroidal flow with higher edge plasma density persists in the 2-fluid MHD model. These findings may explain the ELM mitigation and suppression by toroidal rotation in higher collisionality regime due to the enhancement of plasma density obtained in recent EAST experiments.

  6. Laboratory Observation of a Plasma-Flow-State Transition from Diverging to Stretching a Magnetic Nozzle

    Science.gov (United States)

    Takahashi, Kazunori; Ando, Akira

    2017-06-01

    An axial magnetic field induced by a plasma flow in a divergent magnetic nozzle is measured when injecting the plasma flow from a radio frequency (rf) plasma source located upstream of the nozzle. The source is operated with a pulsed rf power of 5 kW, and the high density plasma flow is sustained only for the initial ˜100 μ sec of the discharge. The measurement shows a decrease in the axial magnetic field near the source exit, whereas an increase in the field is detected at the downstream side of the magnetic nozzle. These results demonstrate a spatial transition of the plasma-flow state from diverging to stretching the magnetic nozzle, where the importance of both the Alfvén and ion Mach numbers is shown.

  7. Numerical investigation of aerodynamic flow actuation produced by surface plasma actuator on 2D oscillating airfoil

    Directory of Open Access Journals (Sweden)

    Minh Khang Phan

    2016-08-01

    Full Text Available Numerical simulation of unsteady flow control over an oscillating NACA0012 airfoil is investigated. Flow actuation of a turbulent flow over the airfoil is provided by low current DC surface glow discharge plasma actuator which is analytically modeled as an ion pressure force produced in the cathode sheath region. The modeled plasma actuator has an induced pressure force of about 2 kPa under a typical experiment condition and is placed on the airfoil surface at 0% chord length and/or at 10% chord length. The plasma actuator at deep-stall angles (from 5° to 25° is able to slightly delay a dynamic stall and to weaken a pressure fluctuation in down-stroke motion. As a result, the wake region is reduced. The actuation effect varies with different plasma pulse frequencies, actuator locations and reduced frequencies. A lift coefficient can increase up to 70% by a selective operation of the plasma actuator with various plasma frequencies and locations as the angle of attack changes. Active flow control which is a key advantageous feature of the plasma actuator reveals that a dynamic stall phenomenon can be controlled by the surface plasma actuator with less power consumption if a careful control scheme of the plasma actuator is employed with the optimized plasma pulse frequency and actuator location corresponding to a dynamic change in reduced frequency.

  8. Kinetic approach to the formation of 3D electromagnetic structures in flows of expanding plasma coronas. II. flow anisotropy parameters

    Science.gov (United States)

    Gubchenko, V. M.

    2015-12-01

    The formation of magnetic structures in moving hot solar coronal plasma and hot collisionless laser-produced plasma, as determined by nonlinear criteria for weak and strong magnetization on the basis of the friction parameter Γ B and Alfven number M A, is considered within the Vlasov and Maxwell equations in the second part of the work. The flow velocities are lower then the thermal electron velocity. The energy and pulse anisotropy parameters of a flow, which determine its electromagnetic properties in the Cherenkov resonance line, are calculated by shape of particle distribution function (PDF). The ratio of these parameters is the Q-factor G V ; it characterizes the electromagnetic properties of a plasma flow and is expressed via the ratio of diamagnetic and resistive current densities or via the ratio of irregular and diamagnetic plasma scales. A particle flow is similar to a conductive medium at G V ≪ 1 and a diamagnetic medium at G V ≫ 1. The following cases are considered. (1) A plasma flow is specified by an isotropic PDF and interacts with distributed magnetization. Expressions for anisotropy parameters are derived, 3D field structures in the tail wake are found, and a possibility of topological reconstruction into a compact state under variation in the parameter G V is shown. (2) A plasma flow is specified by an isotropic PDF; a steady-state diamagnetic current layer, characterized by an anisotropic PDF, is immersed inside it. The system is in the diamagnetic state G ≫ 1. The generalized anisotropy parameter is calculated and a possibility of the excitation of three types of diamagnetic structures with low resistive currents is shown. (3) The nonlinear dynamics of anisotropic quasi-current-free plasma ( G =-1), in which the diamagnetic and resistive current densities locally compensate each other in the phase space of particle velocities, is studied. This dynamics is implemented in the long wavelength limit in plasma with an anisotropic PDF.

  9. Renal blood flow, early distal sodium, and plasma renin concentrations during osmotic diuresis

    DEFF Research Database (Denmark)

    Leyssac, P P; Holstein-Rathlou, N H; Skøtt, O

    2000-01-01

    .6 mmHg. Urine flow increased 10-fold, and sodium excretion increased by 177%. Plasma renin concentration (PRC) increased by 58%. Renal blood flow and glomerular filtration rate decreased, however end-proximal flow remained unchanged. After a similar volume of hypotonic glucose (152 mM), ED...

  10. A plasma flow vortex in the magnetotail and its related ionospheric signatures

    Directory of Open Access Journals (Sweden)

    C. L. Tang

    2012-03-01

    Full Text Available We presented a large-scale plasma flow vortex event that occurred on 1 March 2009 observed by Time History of Events and Macroscale Interactions during Substorms (THEMIS satellites. During the interval, THEMIS satellites were located in the premidnight region between 11 and 16 RE downtail. Dawnward-earthward plasma flows were seen initially in the magnetotail, followed by duskward-tailward flows. This suggests that a clockwise plasma flow vortex (seen from above the equatorial plane was observed on the dawn side of the plasma sheet. Furthermore, high energy (>1 keV electrons were observed. Auroral images at 427.8 nm and THEMIS white light all-sky imager (ASI at Fort Smith showed a discrete auroral patch formed at the poleward of the auroral oval, it then intensified. It extended eastward and equatorward first and followed by westward motion to form the clockwise auroral vortex. The auroral feature corresponded to the ionospheric signatures of the plasma flow vortex in the magnetotail when the Alfvén transit time between the magnetotail and the ionosphere was taken into account. We suggest that the large-scale clockwise plasma flow vortex in association with the high energy (>1 keV electrons on the dawn side of the plasma sheet generated a downward field-aligned current (FAC that caused the related ionospheric signatures. The plasma flow vortex had rotational flow speeds of up to 300 km s−1. The current density associated with the plasma flow vortex was estimated at 2.0 μA m−2, mapped to the ionosphere.

  11. Formation of the compression zone in a plasma flow generated by a magnetoplasma compressor

    Science.gov (United States)

    Solyakov, D. G.; Petrov, Yu. V.; Garkusha, I. E.; Chebotarev, V. V.; Ladygina, M. S.; Cherednichenko, T. N.; Morgal', Ya. I.; Kulik, N. V.; Stal'tsov, V. V.; Eliseev, D. V.

    2013-12-01

    Processes occurring in a plasma flow generated by a magnetoplasma compressor (MPC) during the formation of the compression zone are discussed. The paper presents results of measurements of the spatial distribution of the electric current in the plasma flow, the temporal and spatial (along the flow) distributions of the plasma density, and the profiles of the velocity of individual flow layers along the system axis. The spatial distribution of the electromagnetic force in the flow is analyzed. It is shown that the plasma flow is decelerated when approaching the compression zone and reaccelerated after passing it. In this case, the plasma flow velocity decreases from ν = (2-3) × 107 cm/s at the MPC output to ν < 106 cm/s in the region of maximum compression and then again increases to 107 cm/s at a distance of 15-17 cm from the MPC output. In some MPC operating modes, a displacement of the magnetic field from the compression zone and the formation of toroidal electric current vortices in the plasma flow after passing the compression zone were detected.

  12. Formation of the compression zone in a plasma flow generated by a magnetoplasma compressor

    Energy Technology Data Exchange (ETDEWEB)

    Solyakov, D. G., E-mail: solyakov@ipp.kharkov.ua; Petrov, Yu. V.; Garkusha, I. E.; Chebotarev, V. V.; Ladygina, M. S.; Cherednichenko, T. N.; Morgal’, Ya. I.; Kulik, N. V.; Stal’tsov, V. V.; Eliseev, D. V. [National Academy of Sciences of Ukraine, Institute of Plasma Physics, National Science Center Kharkiv Institute of Physics and Technology (Ukraine)

    2013-12-15

    Processes occurring in a plasma flow generated by a magnetoplasma compressor (MPC) during the formation of the compression zone are discussed. The paper presents results of measurements of the spatial distribution of the electric current in the plasma flow, the temporal and spatial (along the flow) distributions of the plasma density, and the profiles of the velocity of individual flow layers along the system axis. The spatial distribution of the electromagnetic force in the flow is analyzed. It is shown that the plasma flow is decelerated when approaching the compression zone and reaccelerated after passing it. In this case, the plasma flow velocity decreases from ν = (2–3) × 10{sup 7} cm/s at the MPC output to ν < 10{sup 6} cm/s in the region of maximum compression and then again increases to 10{sup 7} cm/s at a distance of 15–17 cm from the MPC output. In some MPC operating modes, a displacement of the magnetic field from the compression zone and the formation of toroidal electric current vortices in the plasma flow after passing the compression zone were detected.

  13. Advanced plasma flow simulations of cathodic-arc and ferroelectric plasma sources for neutralized drift compression experiments

    Directory of Open Access Journals (Sweden)

    Adam B. Sefkow

    2008-07-01

    Full Text Available Large-space-scale and long-time-scale plasma flow simulations are executed in order to study the spatial and temporal evolution of plasma parameters for two types of plasma sources used in the neutralized drift compression experiment (NDCX. The results help assess the charge neutralization conditions for ion beam compression experiments and can be employed in more sophisticated simulations, which previously neglected the dynamical evolution of the plasma. Three-dimensional simulations of a filtered cathodic-arc plasma source show the coupling efficiency of the plasma flow from the source to the drift region depends on geometrical factors. The nonuniform magnetic topology complicates the well-known general analytical considerations for evaluating guiding-center drifts, and particle-in-cell simulations provide a self-consistent evaluation of the physics in an otherwise challenging scenario. Plasma flow profiles of a ferroelectric plasma source demonstrate that the densities required for longitudinal compression experiments involving ion beams are provided over the drift length, and are in good agreement with measurements. Simulations involving azimuthally asymmetric plasma creation conditions show that symmetric profiles are nevertheless achieved at the time of peak on-axis plasma density. Also, the ferroelectric plasma expands upstream on the thermal expansion time scale, and therefore avoids the possibility of penetration into the acceleration gap and transport sections, where partial neutralization would increase the beam emittance. Future experiments on NDCX will investigate the transverse focusing of an axially compressing intense charge bunch to a sub-mm spot size with coincident focal planes using a strong final-focus solenoid. In order to fill a multi-tesla solenoid with the necessary high-density plasma for beam charge neutralization, the simulations predict that supersonically injected plasma from the low-field region will penetrate and

  14. Electrically driving large magnetic Reynolds number flows on the Madison plasma dynamo experiment

    Science.gov (United States)

    Weisberg, David; Wallace, John; Peterson, Ethan; Endrezzi, Douglass; Forest, Cary B.; Desangles, Victor

    2015-11-01

    Electrically-driven plasma flows, predicted to excite a large-scale dynamo instability, have been generated in the Madison plasma dynamo experiment (MPDX), at the Wisconsin Plasma Astrophysics Laboratory. Numerical simulations show that certain topologies of these simply-connected flows may be optimal for creating a plasma dynamo and predict critical thresholds as low as Rmcrit =μ0 σLV = 250 . MPDX plasmas are shown to exceed this critical Rm , generating large (L = 1 . 4 m), warm (Te > 10 eV), unmagnetized (MA > 1) plasmas where Rm torque in Helium plasmas. Detailed Mach probe measurements of plasma velocity for two flow topologies will be presented: edge-localized drive using the multi-cusp boundary field, and volumetric drive using an axial Helmholtz field. Radial velocity profiles show that edge-driven flow is established via ion viscosity but is limited by a volumetric neutral drag force (χ ~ 1 / (ντin)), and measurements of velocity shear compare favorably to Braginskii transport theory. Volumetric flow drive is shown to produce stronger velocity shear, and is characterized by the radial potential gradient as determined by global charge balance.

  15. Investigation of plasma flow in vacuum arc with hot cathode

    Science.gov (United States)

    Amirov, R.; Vorona, N.; Gavrikov, A.; Lizyakin, G.; Polistchook, V.; Samoylov, I.; Smirnov, V.; Usmanov, R.; Yartsev, I.

    2014-11-01

    One of the crucial problems which appear under development of plasma technology processing of spent nuclear fuel (SNF) is the design of plasma source. The plasma source must use solid SNF as a raw material. This article is devoted to experimental study of vacuum arc with hot cathode made of gadolinium that may consider as the simple model of SNF. This vacuum discharge was investigated in wide range of parameters. During the experiments arc current and voltage, cathode temperature, and heat flux to the cathode were measured. The data on plasma spectrum and electron temperature were obtained. It was shown that external heating of the cathode allows change significantly the main parameters of plasma. It was established by spectral and probe methods that plasma jet in studied discharge may completely consist of single charged ions.

  16. Numerical and Experimental Investigation of Turbulent Transport Control via Shaping of Radial Plasma Flow Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Gilmore, Mark Allen [Univ. of New Mexico, Albuquerque, NM (United States)

    2017-02-05

    Turbulence, and turbulence-driven transport are ubiquitous in magnetically confined plasmas, where there is an intimate relationship between turbulence, transport, instability driving mechanisms (such as gradients), plasma flows, and flow shear. Though many of the detailed physics of the interrelationship between turbulence, transport, drive mechanisms, and flow remain unclear, there have been many demonstrations that transport and/or turbulence can be suppressed or reduced via manipulations of plasma flow profiles. This is well known in magnetic fusion plasmas [e.g., high confinement mode (H-mode) and internal transport barriers (ITB’s)], and has also been demonstrated in laboratory plasmas. However, it may be that the levels of particle transport obtained in such cases [e.g. H-mode, ITB’s] are actually lower than is desirable for a practical fusion device. Ideally, one would be able to actively feedback control the turbulent transport, via manipulation of the flow profiles. The purpose of this research was to investigate the feasibility of using both advanced model-based control algorithms, as well as non-model-based algorithms, to control cross-field turbulence-driven particle transport through appropriate manipulation of radial plasma flow profiles. The University of New Mexico was responsible for the experimental portion of the project, while our collaborators at the University of Montana provided plasma transport modeling, and collaborators at Lehigh University developed and explored control methods.

  17. Cross-tail velocity component in the plasma sheet fast flows

    Directory of Open Access Journals (Sweden)

    N. P. Dmitrieva

    2008-06-01

    Full Text Available The flux transfer in the magnetotail plasma sheet is mainly provided by the tail-aligned fast plasma flows (Bursty Bulk Flows – BBFs. In this paper we study the events with a large cross-tail velocity component, including their occurrence and relationship to the standard BBFs. We found out that a significant part of large Vy events are a subgroup connected with the BBFs propagation. The maximal deviation of the velocity vector from the X direction (about 40–50 degrees, on average is observed near the BBFs' leading front in the sheath, where the fast flow interacts with surrounding plasma. The average variation of the velocity direction in the vicinity of the BBF resembles a plasma vortex. Our results support the model, in which the BBF represents a polarized, bubble-like flux tube, propagating through the plasma sheet.

  18. Cross-tail velocity component in the plasma sheet fast flows

    Directory of Open Access Journals (Sweden)

    N. P. Dmitrieva

    2008-06-01

    Full Text Available The flux transfer in the magnetotail plasma sheet is mainly provided by the tail-aligned fast plasma flows (Bursty Bulk Flows – BBFs. In this paper we study the events with a large cross-tail velocity component, including their occurrence and relationship to the standard BBFs. We found out that a significant part of large Vy events are a subgroup connected with the BBFs propagation. The maximal deviation of the velocity vector from the X direction (about 40–50 degrees, on average is observed near the BBFs' leading front in the sheath, where the fast flow interacts with surrounding plasma. The average variation of the velocity direction in the vicinity of the BBF resembles a plasma vortex. Our results support the model, in which the BBF represents a polarized, bubble-like flux tube, propagating through the plasma sheet.

  19. Magnetogasdynamic effects during the interaction between a gas and erosion plasma flows in a magnetoplasma compressor

    Science.gov (United States)

    Ardelian, N. V.; Kamrukov, A. S.; Kozlov, N. P.; Kosmachevskii, K. V.; Popov, Iu. P.

    The physics of the interaction between a gas and erosion plasma flows is examined with reference to the results of a numerical experiment. It is shown that the interaction of a radially inhomogeneous flow with a deformable gas obstacle leads to the formation of a conical shock MHD-wave, with a local increase in pressure, temperature, and magnetic field at its front. Behind the shock wave, the plasma flow turns parallel to the contact boundary, with a noticeable increase in the radial velocity component. This leads to a significant increase in flow cumulation efficiency in comparison with a vacuum magnetoplasma compressor.

  20. A study of gas flow pattern, undercutting and torch modification in variable polarity plasma arc welding

    Science.gov (United States)

    Mcclure, John C.; Hou, Haihui Ron

    1994-01-01

    A study on the plasma and shield gas flow patterns in variable polarity plasma arc (VPPA) welding was undertaken by shadowgraph techniques. Visualization of gas flow under different welding conditions was obtained. Undercutting is often present with aluminum welds. The effects of torch alignment, shield gas flow rate and gas contamination on undercutting were investigated and suggestions made to minimize the defect. A modified shield cup for the welding torch was fabricated which consumes much less shield gas while maintaining the weld quality. The current torch was modified with a trailer flow for Al-Li welding, in which hot cracking is a critical problem. The modification shows improved weldablility on these alloys.

  1. Dynamics of formation of the compression plasma flow in a miniature magnetoplasma compressor

    Science.gov (United States)

    Astashinskii, V. M.; Kuz'mitskii, A. M.; Mishchuk, A. A.

    2011-09-01

    Results are presented of studying integral parameters of the developed miniature gas-discharge magnetoplasma compressor and dynamics of formation of the compression plasma flow. Energy parameters of the discharge in this system are determined.

  2. Statistical study of high-latitude plasma flow during magnetospheric substorms

    Directory of Open Access Journals (Sweden)

    G. Provan

    2004-11-01

    Full Text Available We have utilised the near-global imaging capabilities of the Northern Hemisphere SuperDARN radars, to perform a statistical superposed epoch analysis of high-latitude plasma flows during magnetospheric substorms. The study involved 67 substorms, identified using the IMAGE FUV space-borne auroral imager. A substorm co-ordinate system was developed, centred on the magnetic local time and magnetic latitude of substorm onset determined from the auroral images. The plasma flow vectors from all 67 intervals were combined, creating global statistical plasma flow patterns and backscatter occurrence statistics during the substorm growth and expansion phases. The commencement of the substorm growth phase was clearly observed in the radar data 18-20min before substorm onset, with an increase in the anti-sunward component of the plasma velocity flowing across dawn sector of the polar cap and a peak in the dawn-to-dusk transpolar voltage. Nightside backscatter moved to lower latitudes as the growth phase progressed. At substorm onset a flow suppression region was observed on the nightside, with fast flows surrounding the suppressed flow region. The dawn-to-dusk transpolar voltage increased from ~40kV just before substorm onset to ~75kV 12min after onset. The low-latitude return flow started to increase at substorm onset and continued to increase until 8min after onset. The velocity flowing across the polar-cap peaked 12-14min after onset. This increase in the flux of the polar cap and the excitation of large-scale plasma flow occurred even though the IMF Bz component was increasing (becoming less negative during most of this time. This study is the first to statistically prove that nightside reconnection creates magnetic flux and excites high-latitude plasma flow in a similar way to dayside reconnection and that dayside and nightside reconnection, are two separate time-dependent processes.

  3. CONVECTIVE AND RADIATIVE HEAT TRANSFER DURING MELTING WIRE IN THE FLOW OF PLASMA ARC

    Directory of Open Access Journals (Sweden)

    A. V. Yershov

    2014-07-01

    Full Text Available The features of convection and radiant heat exchange of argon plasma cross flow from the surface of the melted butt of steel wire with plasma coating on metal surface are considered. We investigated the uneven distribution of convective heat flow around the perimeter of the heating wire The main part of convective heat flux of plasma centered on its wire is shown,. The density of convective heat flow in the neighborhood of its critical point during the heating of the plasma flow in a wire coating is defined. Calculation of the heat flux density is a 3-d plasma radiation. It is shown that the spherical layer of 2 mm radius of argon plasma is optically transparent in the temperature range (8–20 103 k, since the degree of this layer blackness is considerably less than one. It is determined that the density of heat flow radiation of steel electrode surface is negligible compared with the radiation from the plasma column with the temperature 12·103 К

  4. Modeling and experiments on differential pumping in linear plasma generators operating at high gas flows

    NARCIS (Netherlands)

    van Eck, H. J. N.; Koppers, W. R.; van Rooij, G. J.; W. J. Goedheer,; Engeln, R.; D.C. Schram,; Cardozo, N. J. L.; Kleyn, A. W.

    2009-01-01

    The direct simulation Monte Carlo (DSMC) method was used to investigate the efficiency of differential pumping in linear plasma generators operating at high gas flows. Skimmers are used to separate the neutrals from the plasma beam, which is guided from the source to the target by a strong axial

  5. Optical Diagnostics of Air Flows Induced in Surface Dielectric Barrier Discharge Plasma Actuator

    Science.gov (United States)

    Kobatake, Takuya; Deguchi, Masanori; Suzuki, Junya; Eriguchi, Koji; Ono, Kouichi

    2014-10-01

    A surface dielectric barrier discharge (SDBD) plasma actuator has recently been intensively studied for the flow control over airfoils and turbine blades in the fields of aerospace and aeromechanics. It consists of two electrodes placed on both sides of the dielectric, where one is a top powered electrode exposed to the air, and the other is a bottom grounded electrode encapsulated with an insulator. The unidirectional gas flow along the dielectric surfaces is induced by the electrohydrodynamic (EHD) body force. It is known that the thinner the exposed electrode, the greater the momentum transfer to the air is, indicating that the thickness of the plasma is important. To analyze plasma profiles and air flows induced in the SDBD plasma actuator, we performed time-resolved and -integrated optical emission and schlieren imaging of the side view of the SDBD plasma actuator in atmospheric air. We applied a high voltage bipolar pulse (4-8 kV, 1-10 kHz) between electrodes. Experimental results indicated that the spatial extent of the plasma is much smaller than that of the induced flows. Experimental results further indicated that in the positive-going phase, a thin and long plasma is generated, where the optical emission is weak and uniform; on the other hand, in the negative-going phase, a thick and short plasma is generated, where a strong optical emission is observed near the top electrode.

  6. Fuelling and plasma flow change by compact torus injection into the STOR-M Tokamak

    Science.gov (United States)

    Onchi, Takumi; Liu, Yelu; Dreval, Mykola; McColl, David; Xiao, Chijin; Hirose, Akira; Asai, Tomohiko; Wolfe, Sean

    2012-10-01

    The Saskatchewan TORus Modified (STOR-M) tokamak is equipped with a Compact Torus (CT) injector for tangential (toroidal) injection of a high density plasmoid at a velocity of 150 km/s. The objectives of CT injection (CTI) are to fuel the core region of tokamak and optimize the bootstrap current in future reactors by control of the plasma pressure gradient. After CTI, the line averaged density along central chord increases from ne˜x 10^12 to 1.5 x 10^13 [cm-3]. Measurement of soft X-ray bremsstrahlung emission profile indicates a steeper density gradient is generated after the asymmetric density profile is formed and the profile become symmetry again in STOR-M. Intrinsic impurity ion flows have been measured with ion Doppler spectroscopy. Significant radial velocity shear from center to edge region is observed even in Ohmic discharges. The toroidal flow direction is found to depend on the plasma current direction. CTI also modifies toroidal plasma flow. The edge plasma flow increases by 5 km/s 1millisecond after CTI. During these milliseconds of time, toroidal flow shear is also increased from 214.3 to 285.7 [10^3 x1/s]. A few milliseconds later than that time, plasma flow slows down, but plasma confinement is improved. Hα emission decreases by 50%.

  7. Surface treatment by the ion flow from electron beam generated plasma in the forevacuum pressure range

    Directory of Open Access Journals (Sweden)

    Klimov Aleksandr

    2018-01-01

    Full Text Available The paper presents research results of peculiarities of gas ion flows usage and their generation from large plasma formation (>50 sq.cm obtained by electron beam ionization of gas in the forevacuum pressure range. An upgraded source was used for electron beam generation, which allowed obtaining ribbon electron beam with no transmitting magnetic field. Absence of magnetic field in the area of ion flow formation enables to obtain directed ion flows without distorting their trajectories. In this case, independent control of current and ion energy is possible. The influence of electron beam parameters on the parameters of beam plasma and ion flow – current energy and density – was determined. The results of alumina ceramics treatment with a beam plasma ions flow are given.

  8. Generation Control of ZnO Nanoparticles Using a Coaxial Gas-Flow Pulse Plasma Ar/O2 Plasma

    Directory of Open Access Journals (Sweden)

    Hiroki Shirahata

    2015-01-01

    Full Text Available Generation of ZnO nanoparticles was investigated using a coaxial gas-flow pulse plasma. We studied how zinc atoms, sputtered from a zinc target, reacted with oxygen in a plasma and/or on a substrate to form ZnO nanoparticles when the discharge parameters, such as applied pulse voltage and gas flow rate, were controlled in an O2/Ar plasma. The formation processes were estimated by SEM, TEM, and EDX. We observed many ZnO nanoparticles deposited on Si substrate. The particle yield and size were found to be controlled by changing the experimental parameters. The diameter of the particles was typically 50–200 nm.

  9. DoE Plasma Center for Momentum Transport and Flow Self-Organization in Plasmas: Non-linear Emergent Structure Formation in magnetized Plasmas and Rotating Magnetofluids

    Energy Technology Data Exchange (ETDEWEB)

    Forest, Cary B. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics

    2016-11-10

    This report covers the UW-Madison activities that took place within a larger DoE Center Administered and directed by Professor George Tynan at the University of California, San Diego. The work at Wisconsin will also be covered in the final reporting for the entire center, which will be submitted by UCSD. There were two main activities, one experimental and one that was theoretical in nature, as part of the Center activities at the University of Wisconsin, Madison. First, the Center supported an experimentally focused postdoc (Chris Cooper) to carry out fundamental studies of momentum transport in rotating and weakly magnetized plasma. His experimental work was done on the Plasma Couette Experiment, a cylindrical plasma confinement device, with a plasma flow created through electromagnetically stirring plasma at the plasma edge facilitated by arrays of permanent magnets. Cooper's work involved developing optical techniques to measure the ion temperature and plasma flow through Doppler-shifted line radiation from the plasma argon ions. This included passive emission measurements and development of a novel ring summing Fabry-Perot spectroscopy system, and the active system involved using a diode laser to induce fluorescence. On the theoretical side, CMTFO supported a postdoc (Johannes Pueschel) to carry out a gyrokinetic extension of residual zonal flow theory to the case with magnetic fluctuations, showing that magnetic stochasticity disrupts zonal flows. The work included a successful comparison with gyrokinetic simulations. This work and its connection to the broader CMTFO will be covered more thoroughly in the final CMTFO report from Professor Tynan.

  10. Three-dimensional rotational plasma flows near solid surfaces in an axial magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Gorshunov, N. M., E-mail: gorshunov-nm@nrcki.ru; Potanin, E. P., E-mail: potanin45@yandex.ru [National Research Center Kurchatov Institute (Russian Federation)

    2016-11-15

    A rotational flow of a conducting viscous medium near an extended dielectric disk in a uniform axial magnetic field is analyzed in the magnetohydrodynamic (MHD) approach. An analytical solution to the system of nonlinear differential MHD equations of motion in the boundary layer for the general case of different rotation velocities of the disk and medium is obtained using a modified Slezkin–Targ method. A particular case of a medium rotating near a stationary disk imitating the end surface of a laboratory device is considered. The characteristics of a hydrodynamic flow near the disk surface are calculated within the model of a finite-thickness boundary layer. The influence of the magnetic field on the intensity of the secondary flow is studied. Calculations are performed for a weakly ionized dense plasma flow without allowance for the Hall effect and plasma compressibility. An MHD flow in a rotating cylinder bounded from above by a retarding cap is considered. The results obtained can be used to estimate the influence of the end surfaces on the main azimuthal flow, as well as the intensities of circulating flows in various devices with rotating plasmas, in particular, in plasma centrifuges and laboratory devices designed to study instabilities of rotating plasmas.

  11. Numerical Simulations of NS-DBD Plasma Actuators For Flow Control

    NARCIS (Netherlands)

    Popov, I.

    2016-01-01

    Nanosecond dielectric barrier discharge (NS-DBD) plasma actuators is relatively
    new means of flow control. It has several advantages compared to more conventional
    means of flow control, such as small size, low weight, fast response time
    and controllability. It has been demonstrated to be

  12. Simulations of collisionless counter-propagating plasma flows in support of two-wire implosion experiments

    Science.gov (United States)

    Caplinger, James; Sotnikov, Vladimir; Hamilton, Andrew; Plasma Physics Sensors Laboratory Team

    2017-10-01

    One of the simplest configurations leading to colliding plasma flows is created by driving strong currents through a pair of parallel wires. The azimuthal magnetic fields generated around each wire, and the Ohmic current dissipation and heating occurring upon wire evaporation, launches powerful radial outflows of magnetized plasmas. Upon colliding they form a flow pattern suggestive of magnetic field reconnection, and the development of various plasma instabilities. In the current effort, we analyzed collision of two high-temperature precursor light ion plasma flows via PIC (Particle-In-Cell) simulations using LSP. The aim is to demonstrate the appearance of an electric field parallel to the direction of a plasma flow. This field appears in colliding plasma flows due to the charge separation and is associated with the Buneman instability. It is responsible for the creation of ExB drift of electrons. Next, an interaction between drifting electrons and unmagnetized ions, moving parallel to them, lead to excitation of a modified Buneman instability in the frequency range close to the Lower-Hybrid frequency. Simulation results will allow us to identify the characteristics of nonlinear density fluctuations that appear in the process of such an interaction. This work was supported by the Air Force Office of Scientific Research.

  13. Numerical Simulation of Non-Equilibrium Plasma Discharge for High Speed Flow Control

    Science.gov (United States)

    Balasubramanian, Ramakrishnan; Anandhanarayanan, Karupannasamy; Krishnamurthy, Rajah; Chakraborty, Debasis

    2017-06-01

    Numerical simulation of hypersonic flow control using plasma discharge technique is carried out using an in-house developed code CERANS-TCNEQ. The study is aimed at demonstrating a proof of concept futuristic aerodynamic flow control device. The Kashiwa Hypersonic and High Temperature wind tunnel study of plasma discharge over a flat plate had been considered for numerical investigation. The 7-species, 18-reaction thermo-chemical non-equilibrium, two-temperature air-chemistry model due Park is used to model the weakly ionized flow. Plasma discharge is modeled as Joule heating source terms in both the translation-rotational and vibrational energy equations. Comparison of results for plasma discharge at Mach 7 over a flat plate with the reference data reveals that the present study is able to mimic the exact physics of complex flow such as formation of oblique shock wave ahead of the plasma discharge region with a resultant rise in surface pressure and vibrational temperature up to 7000 K demonstrating the use of non-equilibrium plasma discharge for flow control at hypersonic speeds.

  14. Characteristic Boundary Conditions for Numerical Magnetohydrodynamic (MHD) Simulation of Solar and Laboratory Plasma Flows

    Science.gov (United States)

    Wu, S. T.; Wang, A. H.; Cassibry, J.

    2010-09-01

    We discuss the self-consistent time-dependent numerical boundary conditions for magnetohydrodynamic (MHD) simulation to study the solar and laboratory plasma dynamics. It is well known that these plasma flows cover from the sub-sonic and sub-Alfvénic to super-sonic and super-Alfvénic region. Mathematically, the set of governing differential equations is transited from elliptical to hyperbolic type. In order to assure self-consistency, characteristic boundary conditions need to be used because the information propagating according to these characteristics will affect the solutions inside the computational domain. To illustrate the importance of the characteristic boundary conditions, two examples are given; one for solar plasma which is to study the energy and magnetic flux from the sub-photosphere to the corona, and the other one concerns laboratory plasma flow for the investigation of sub-Alfvénic inlet boundary conditions of an MHD nozzle flow.

  15. Plasma sheet fast flows and auroral dynamics during substorm: a case study

    Directory of Open Access Journals (Sweden)

    N. L. Borodkova

    2002-03-01

    Full Text Available Interball-1 observations of a substorm development in the mid-tail on 16 December 1998 are compared with the auroral dynamics obtained from the Polar UV imager. Using these data, the relationship between plasma flow directions in the tail and the location of the auroral activation is examined. Main attention is given to tailward and earth-ward plasma flows, interpreted as signatures of a Near Earth Neutral Line (NENL. It is unambiguously shown that in the mid-plasma sheet the flows were directed tailward when the auroral bulge developed equatorward of the spacecraft ionospheric footprint. On the contrary, when active auroras moved poleward of the Interball-1 projection, earthward fast flow bursts were observed. This confirms the concept that the NENL (or flow reversal region is the source of auroras forming the poleward edge of the auroral bulge. The observed earthward flow bursts have all typical signatures of Bursty Bulk Flows (BBFs, described by Angelopolous et al. (1992. These BBFs are related to substorm activations starting at the poleward edge of the expanded auroral bulge. We interpret the BBFs as a result of reconnection pulses occurring tail-ward of Interball-1. In addition, some non-typically observed phenomena were detected in the plasma sheet during this substorm: (i tailward/earthward flows were superimposed on a very strong duskward flow, and (ii wavy structures of both magnetic field and plasma density were registered. The latter observation is probably linked to the filamentary structure of the current sheet.Key words. Magnetospheric physics (auroral phenomena; plasma sheet; storms and substorms

  16. Bottled Water Basics

    Science.gov (United States)

    ... of dollars each year to buy it (Beverage Marketing Corporation, 2004) Some people drink bottled water as ... has been treated to meet the U.S. Pharmacopeia definition of purified water. Purified water is essentially free ...

  17. Studies of plasma flow past Jupiter's satellite Io

    Science.gov (United States)

    Linker, Jon

    1996-01-01

    We have investigated the interaction of Io, Jupiter's innermost Galilean satellite, with the Io plasma torus. The interaction of Io with the plasma surrounding it has been a subject of interest for almost 30 years, dating from the discovery by Bigg (1964) that radio emissions from the Jovian magnetosphere are controlled by Io's position. Since that time, both ground-based and spacecraft observations have shown that Io is a unique satellite that influences the Jovian magnetosphere in important ways. In particular, material from Io is a major source of plasma for the magnetosphere, and the energy that this plasma harnesses from Jupiter's co-rotating magnetic field is an important power source for the magnetosphere. It is apparent that the local interaction of the torus plasma with Io plays a key role in the formation, composition, and energetics of the Io torus; the interaction is also highly nonlinear. We have modeled this interaction using time-dependent three-dimensional magnetohydrodynamic (MHD) simulations. During this past year, we have used NASA support to develop a new MHD code to study the interaction. As part of the Galileo spacecraft's recent successful insertion into orbit around Jupiter, the spacecraft passed within 900 km of Io's surface. Our calculations have focused on using Galileo particles and fields data to examine a question that was not resolved by the Voyager observations: Does Io have an intrinsic magnetic field? In this progress summary, we describe our efforts on this problem to date.

  18. Magnetic moment of solar plasma and the Kelvin force: -The driving force of plasma up-flow -

    Science.gov (United States)

    Shibasaki, Kiyoto

    2017-04-01

    Thermal plasma in the solar atmosphere is magnetized (diamagnetic). The magnetic moment does not disappear by collisions because complete gyration is not a necessary condition to have magnetic moment. Magnetized fluid is subjected to Kelvin force in non-uniform magnetic field. Generally, magnetic field strength decreases upwards in the solar atmosphere, hence the Kelvin force is directed upwards along the field. This force is not included in the fluid treatment of MHD. By adding the Kelvin force to the MHD equation of motion, we can expect temperature dependent plasma flows along the field which are reported by many observations. The temperature dependence of the flow speed is explained by temperature dependence of magnetic moment. From the observed parameters, we can infer physical parameters in the solar atmosphere such as scale length of the magnetic field strength and the friction force acting on the flowing plasma. In case of closed magnetic field lines, loop-top concentration of hot plasma is expected which is frequently observed.

  19. Simulation and experimental studies on plasma temperature, flow velocity, and injector diameter effects for an inductively coupled plasma.

    Science.gov (United States)

    Lindner, Helmut; Murtazin, Ayrat; Groh, Sebastian; Niemax, Kay; Bogaerts, Annemie

    2011-12-15

    An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., ∼50 μm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule

  20. Observations of plasma vortices in the vicinity of flow-braking: a case study

    Directory of Open Access Journals (Sweden)

    K. Keika

    2009-08-01

    Full Text Available We examine fast plasma flows and magnetic field fluctuations observed by THEMIS at 03:00–03:30 UT on 12 December 2007. All THEMIS probes are situated in the near-Earth plasma sheet (XSM>−10 RE with 1–2 RE spacecraft separations in azimuthal and radial directions. We focus on the observations of plasma convective flows made simultaneously by more than one THEMIS probe. At about 03:10 UT and 03:14 UT, the THEMIS P2 probe observed earthward flows of >100 km/s. The THEMIS P1 probe, located duskward and earthward of P2, observed tailward flows under a positive Bz. The inner most probe THEMIS P4, located at almost the same MLT as THEMIS P1 and P2, did not see any clear flow. We examine the convective flow patterns for the THEMIS observations. We conclude that plasma vortices are formed near the region where the earthward flows slow down and turn in azimuthal directions.

  1. The Efficiency of Quartz Particles Evaporation in the Argon Plasma Flow of the RF Inductively Coupled Plasma Torch

    Directory of Open Access Journals (Sweden)

    Yu. M. Grishin

    2017-01-01

    Full Text Available Owing to high-power density and high-purity plasma, a RF inductively coupled plasma torch (ICPT is widely used both in research laboratory and in industry. The potential RF ICPT application areas are powders spheroidisation, waste treatment, thermal spraying, etc.In the last decade the investigation was focused on the treatment processes of quartz into polycrystalline silicon. An analysis of these results has shown that the increasing productivity and producing high-purity silicon can be achieved only when using the electrodeless radio-frequency induction plasma torches and in case the optimum conditions for evaporation of SiO2solid particles are realized.Optimization of the RF ICPT design and power parameters calls for a wide range of computational studies. In spite of the fact that to date a large number of efforts to calculate the evaporation efficiency of powder materials have been made, a number of issues, as applied to the problem of obtaining silicon, require further research.In this paper, we present the results of a two-dimensional numerical simulation of the heating and evaporation of quartz particles in the RF ICPT channel with axial flow of gases. The main aim is to determine how the axial position of the central tube (through which the particles are injected into the discharge zone, the dispersion of the quartz powder, the amplitude of the discharge current (and, respectively, flow regimes impact on the evaporation efficiency of quartz particles.The paper presented the numerical modeling results of heating and evaporation processes of quartz particles supplied by transporting gas to the RF ICPT channel with axial gas flow (argon. Defined the impact of the axial position of the central tube, the plasma flow regime, the discharge current, the flow rate of transporting gas, and other parameters on the evaporation efficiency of quartz particles.It is shown that the evaporation efficiency of particles reaches its maximum when their

  2. Interaction of a vacuum arc plasma beam with an obstacle positioned normal to the plasma flow

    Energy Technology Data Exchange (ETDEWEB)

    Zarchin, O [Electrical Discharge and Plasma Laboratory, Tel-Aviv University, POB 39040, Tel-Aviv 69978 (Israel); Zhitomirsky, V N [Electrical Discharge and Plasma Laboratory, Tel-Aviv University, POB 39040, Tel-Aviv 69978 (Israel); Goldsmith, S [Electrical Discharge and Plasma Laboratory, Tel-Aviv University, POB 39040, Tel-Aviv 69978 (Israel); Boxman, R L [Electrical Discharge and Plasma Laboratory, Tel-Aviv University, POB 39040, Tel-Aviv 69978 (Israel)

    2003-09-21

    The effect of an obstacle positioned normal to a plasma jet produced by a vacuum arc plasma source on the radial distribution of ion flux in the vicinity of the obstacle was studied. This study was motivated by interest in the mutual influence of tightly packed substrates on coatings in industrial vacuum arc deposition systems. The experimental system consisted of a vacuum arc plasma source, a straight plasma duct, and a multi-probe consisting of a removable disc obstacle and a set of ring probes for measuring the radial ion flux. A dc arc discharge was ignited in vacuum between a truncated cone-shaped Cu cathode and an annular anode. The plasma jet produced by cathode spots passed through the anode aperture into the straight plasma duct. An axial magnetic field guided the plasma jet in the duct. The multi-probe consisted of a removable disc obstacle and a set of five ring probes for measuring the radial plasma flux as a function of distance from the disc obstacle. The rings and the disc probes were coaxially arranged on the multi-probe assembly and positioned so that plasma from the source passed through the ring probes and then encountered the disc. The influence of the obstacle was determined by measuring the ring ion currents, both in the presence of the obstacle, and when the disc obstacle was removed. The difference between the measured ion currents with and without the obstacle was interpreted to be the contribution of reflected or sputtered particles from the obstacle to the radial ion flux. The ring probes were biased by -60 V with respect to the grounded anode, to collect the saturated ion current. The multi-probe was connected to a movable stem, and positioned at different distances from the plasma source. A plasma density of {approx}6 x 10{sup 17} m{sup -3} was estimated in this study based on the ion current to the obstacle. The radial ion flux collected by the ring probes increased by 20-25% due to the presence of the obstacle. As the calculated mean

  3. Fundamentals of Aerodynamic-Flow and Combustion Control by Plasmas

    Science.gov (United States)

    2010-05-14

    appear to be keys parameters. [1] G. Pilla, D. Galley, D.A. Lacoste, F. Lacas , D. Veynante, C.O. Laux “Stabilization of a Turbulent Premixed Flame...produced by the pulse. References: [1] G. Pilla, D. Galley, D.A. Lacoste, F. Lacas , D. Veynante, C.O. Laux, IEEE Transactions on Plasma

  4. Shuttle-era experiments in the area of plasma flow interactions with bodies in space

    Science.gov (United States)

    Samir, U.; Stone, N. H.

    1980-01-01

    A new experimental approach is discussed that can be adopted for studies in the area of plasma flow interactions with bodies in space. The potential use of the Space Shuttle/Orbiter as a near-earth plasma laboratory for studies in space plasma physics and particularly in solar system plasmas is discussed. This new experimental approach holds great promise for studies in the supersonic and sub-Alfvenic flow regime which has applications to the motion of natural satellites around their mother planets in the solar-system (e.g., the satellite Io around the planet Jupiter). A well conceived experimental and theoretical program can lead to a better physical understanding regarding the validity and range of applicability of using gasdynamic, kinetic, and fluid approaches in describing collisionless plasma flow interactions with bodies in a variety of flow regimes. In addition to the above scientific aspects of the program, significant technological advances can be achieved regarding the interaction of space probes in planetary atmospheres/ionospheres and the reliability of using various plasma diagnostic devices on board spacecraft and large space platforms.

  5. Numerical simulation of laminar plasma dynamos in a cylindrical von K\\'arm\\'an flow

    CERN Document Server

    Khalzov, I V; Ebrahimi, F; Schnack, D D; Forest, C B; 10.1063/1.3559472

    2011-01-01

    The results of a numerical study of the magnetic dynamo effect in cylindrical von K\\'arm\\'an plasma flow are presented with parameters relevant to the Madison Plasma Couette Experiment. This experiment is designed to investigate a broad class of phenomena in flowing plasmas. In a plasma, the magnetic Prandtl number Pm can be of order unity (i.e., the fluid Reynolds number Re is comparable to the magnetic Reynolds number Rm). This is in contrast to liquid metal experiments, where Pm is small (so, Re>>Rm) and the flows are always turbulent. We explore dynamo action through simulations using the extended magnetohydrodynamic NIMROD code for an isothermal and compressible plasma model.We also study two-fluid effects in simulations by including the Hall term in Ohm's law. We find that the counter-rotating von K\\'arm\\'an flow results in sustained dynamo action and the self-generation of magnetic field when the magnetic Reynolds number exceeds a critical value. For the plasma parameters of the experiment, this field ...

  6. Gas flow dependence for plasma-needle disinfection of S. mutans bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Goree, J [Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 (United States); Liu Bin [Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 (United States); Drake, David [Dows Institute for Dental Research, Dept. of Endodontics, College of Dentistry, University of Iowa, Iowa City, IA 52242 (United States)

    2006-08-21

    The role of gas flow and transport mechanisms are studied for a small low-power impinging jet of weakly-ionized helium at atmospheric pressure. This plasma needle produces a non-thermal glow discharge plasma that kills bacteria. A culture of Streptococcus mutans (S. mutans) was plated onto the surface of agar, and spots on this surface were then treated with plasma. Afterwards, the sample was incubated and then imaged. These images, which serve as a biological diagnostic for characterizing the plasma, show a distinctive spatial pattern for killing that depends on the gas flow rate. As the flow is increased, the killing pattern varies from a solid circle to a ring. Images of the glow reveal that the spatial distribution of energetic electrons corresponds to the observed killing pattern. This suggests that a bactericidal species is generated in the gas phase by energetic electrons less than a millimetre from the sample surface. Mixing of air into the helium plasma is required to generate the observed O and OH radicals in the flowing plasma. Hydrodynamic processes involved in this mixing are buoyancy, diffusion and turbulence.

  7. Self-separation of blood plasma from whole blood during the capillary flow in microchannel

    Science.gov (United States)

    Nunna, Bharath Babu; Zhuang, Shiqiang; Lee, Eon Soo

    2017-11-01

    Self-separation of blood plasma from whole blood in microchannels is of great importance due to the enormous range of applications in healthcare and diagnostics. Blood is a multiphase complex fluid, composed of cells suspended in blood plasma. RBCs are the suspended particles whose shape changes during the flow of blood. The primary constituents of blood are erythrocytes or red blood cells (RBCs), leukocytes or white blood cells (WBCs), thrombocytes or platelets and blood plasma. The existence of RBCs in blood makes the blood a non-Newtonian fluid. The current study of separation of blood plasma from whole blood during self-driven flows in a single microchannel without bifurcation, by enhancing the capillary effects. The change in the capillary effect results in a change in contact angle which directly influences the capillary flow. The flow velocity directly influences the net force acting on the RBCs and influence the separation process. The experiments are performed on the PDMS microchannels with different contact angles by altering the surface characteristics using plasma treatment. The change in the separation length is studied during the capillary flow of blood in microchannel. Bharath Babu Nunna is a researcher in mechanical engineering and implementing the novel and innovative technologies in the biomedical devices to enhance the sensitivity of the disease diagnosis.

  8. Characteristics of pulsed plasma synthetic jet and its control effect on supersonic flow

    Directory of Open Access Journals (Sweden)

    Di Jin

    2015-02-01

    Full Text Available The plasma synthetic jet is a novel flow control approach which is currently being studied. In this paper its characteristic and control effect on supersonic flow is investigated both experimentally and numerically. In the experiment, the formation of plasma synthetic jet and its propagation velocity in quiescent air are recorded and calculated with time resolved schlieren method. The jet velocity is up to 100 m/s and no remarkable difference has been found after changing discharge parameters. When applied in Mach 2 supersonic flow, an obvious shockwave can be observed. In the modeling of electrical heating, the arc domain is not defined as an initial condition with fixed temperature or pressure, but a source term with time-varying input power density, which is expected to better describe the influence of heating process. Velocity variation with different heating efficiencies is presented and discussed and a peak velocity of 850 m/s is achieved in still air with heating power density of 5.0 × 1012 W/m3. For more details on the interaction between plasma synthetic jet and supersonic flow, the plasma synthetic jet induced shockwave and the disturbances in the boundary layer are numerically researched. All the results have demonstrated the control authority of plasma synthetic jet onto supersonic flow.

  9. Finite toroidal flow generated by unstable tearing mode in a toroidal plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hao, G. Z., E-mail: haogz@swip.ac.cn; Wang, A. K.; Xu, Y. H.; He, H. D.; Xu, M.; Qu, H. P.; Peng, X. D.; Xu, J. Q.; Qiu, X. M. [Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041 (China); Liu, Y. Q. [Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Sun, Y. [Institute of Plasma Physics, Chinese Academic of Sciences, P.O. Box 1126, Hefei 230031 (China); Cui, S. Y. [School of Mathematics and Statistics Science, Ludong University, Yantai 264025 (China)

    2014-12-15

    The neoclassical toroidal plasma viscosity torque and electromagnetic torque, generated by tearing mode (TM) in a toroidal plasma, are numerically investigated using the MARS-Q code [Liu et al., Phys. Plasmas 20, 042503 (2013)]. It is found that an initially unstable tearing mode can intrinsically drive a toroidal plasma flow resulting in a steady state solution, in the absence of the external momentum input and external magnetic field perturbation. The saturated flow is in the order of 0.5%ω{sub A} at the q=2 rational surface in the considered case, with q and ω{sub A} being the safety factor and the Alfven frequency at the magnetic axis, respectively. The generation of the toroidal flow is robust, being insensitive to the given amplitude of the perturbation at initial state. On the other hand, the flow amplitude increases with increasing the plasma resistivity. Furthermore, the initially unstable tearing mode is fully stabilized by non-linear interaction with the self-generated toroidal flow.

  10. Cluster observation of plasma flow reversal in the magnetotail during a substorm

    Directory of Open Access Journals (Sweden)

    A. T. Y. Lui

    2006-08-01

    Full Text Available We investigate in detail a reversal of plasma flow from tailward to earthward detected by Cluster at the downstream distance of ~19 RE in the midnight sector of the magnetotail on 22 August 2001. This flow reversal was accompanied by a sign reversal of the Bz component and occurred during the late substorm expansion phase as revealed by simultaneous global view of auroral activity from IMAGE. We examine the associated Hall current system signature, current density, electric field, Lorentz force, and current dissipation/dynamo term, the last two parameters being new features that have not been studied previously for plasma flow reversals. It is found that (1 there was no clear quadrupole Hall current system signature organized by the flow reversal time, (2 the x-component of the Lorentz force did not change sign while the other two did, (3 the timing sequence of flow reversal from the Cluster configuration did not match tailward motion of a single plasma flow source, (4 the electric field was occasionally dawnward, producing a dynamo effect, and (5 the electric field was occasionally larger at the high-latitude plasma sheet than near the neutral sheet. These observations are consistent with the current disruption model for substorms in which these disturbances are due to shifting dominance of multiple current disruption sites and turbulence at the observing location.

  11. Energy Flow in Dense Off-Equilibrium Plasma

    Science.gov (United States)

    2016-07-15

    is the collision time. In this limit the motion is reversible and no energy is absorbed by the plasma. A theory which explains the conversion of...bremsstrahlung where an electron absorbs light during a “ collision ” with an ion [14]. The collisionality in SCP is greatly affected by collective screening...LOS ANGELES, CA 90095-0001 07/15/2016 Final Report DISTRIBUTION A: Distribution approved for public release. Air Force Research Laboratory AF Office

  12. Bombardment of Thin Lithium Films with Energetic Plasma Flows

    Science.gov (United States)

    Gray, Travis Kelly

    2009-01-01

    The Divertor Erosion and Vapor Shielding Experiment (DEVEX) has been constructed in the Center for Plasma-Material Interactions at the University of Illinois at Urbana-Champaign. It consists of a conical theta-pinch connected to a 60 kV, 36 [mu]F capacitor bank which is switched with a rise time of 3.5 [mu]s. This results in a peak current of 300…

  13. Dielectric Barrier Discharge Plasma Actuator for Flow Control

    Science.gov (United States)

    Opaits, Dmitry, F.

    2012-01-01

    This report is Part II of the final report of NASA Cooperative Agreement contract no. NNX07AC02A. It includes a Ph.D. dissertation. The period of performance was January 1, 2007 to December 31, 2010. Part I of the final report is the overview published as NASA/CR-2012- 217654. Asymmetric dielectric barrier discharge (DBD) plasma actuators driven by nanosecond pulses superimposed on dc bias voltage are studied experimentally. This produces non-self-sustained discharge: the plasma is generated by repetitive short pulses, and the pushing of the gas occurs primarily due to the bias voltage. The parameters of ionizing pulses and the driving bias voltage can be varied independently, which adds flexibility to control and optimization of the actuators performance. The approach consisted of three elements coupled together: the Schlieren technique, burst mode of plasma actuator operation, and 2-D numerical fluid modeling. During the experiments, it was found that DBD performance is severely limited by surface charge accumulation on the dielectric. Several ways to mitigate the surface charge were found: using a reversing DC bias potential, three-electrode configuration, slightly conductive dielectrics, and semi conductive coatings. Force balance measurements proved the effectiveness of the suggested configurations and advantages of the new voltage profile (pulses+bias) over the traditional sinusoidal one at relatively low voltages. In view of practical applications certain questions have been also addressed, such as electrodynamic effects which accompany scaling of the actuators to real size models, and environmental effects of ozone production by the plasma actuators.

  14. BOTTLE MATERIAL AND CLEANSING PROCEDURES OF INFANT FEEDING BOTTLES

    National Research Council Canada - National Science Library

    Kuan, Wen-Hui; Chen, Yi-Lang

    2016-01-01

    The cleanliness of feeding bottles is vital for child health. Although machine cleansing of bottles in the food industry has been established, mechanical and manual cleansing methods are highly variable...

  15. Studies of Plasma Flow Past Jupiters Satellite Io

    Science.gov (United States)

    Linker, Jon A.

    1997-01-01

    We have investigated the interaction of Io, Jupiter's innermost Galilean satellite, with the Io plasma torus, and the interaction of Ganymede with the corotating Jovian plasma. With the successful insertion of the Galileo spacecraft into orbit around Jupiter, many new observations have been made of the Jovian magnetosphere. Some of the most exciting results thus far have been in regards to Jupiter's satellites, Io and Ganymede. In both cases the large perturbations to the background (Jovian) magnetic field have been consistent with the satellites' possession of an intrinsic magnetic field. The gravity measurements implying a differentiated core at both Io and Ganymede makes internal generation of a magnetic field by dynamo action in these satellites plausible, and, in the case of Ganymede, the identification of an intrinsic field is apparently unambiguous. For Io the situation is less clear, and further analysis is necessary to answer this important question. During the past year, we have used time-dependent three-dimensional magnetohydrodynamic (MHD) simulations to study these plasma-moon interactions. The results from these simulations have been used directly in the analysis of the Galileo magnetometer data. Our primary emphasis has been on the Io interaction, but we recently presented results on the Ganymede interaction as well. In this progress summary we describe our efforts on these problems to date.

  16. Analysis of whole blood samples with low gas flow inductively coupled plasma-optical emission spectrometry.

    Science.gov (United States)

    Nowak, Sascha; Künnemeyer, Jens; Terborg, Lydia; Trümpler, Stefan; Günsel, Andreas; Wiesmüller, Gerhard A; Karst, Uwe; Buscher, Wolfgang

    2015-01-01

    Low gas flow ICP-OES with a total argon consumption below 0.7 L/min is introduced for the analysis of trace elements in blood samples to investigate the influence of samples containing an organic solvent in a demanding matrix on the performance of this plasma for the first time. Therefore, gadolinium was determined in human plasma samples and mercury in red blood cells, human plasma, and precipitated plasma protein fraction. Limits of detection (LOD) were determined to be in the low microgram per liter range for the analytes and the accuracy of the method was assessed by comparison with a conventional Fassel-type torch-based ICP-OES. It was proven that the low gas flow ICP-OES leads to comparable results with the instrument based on the Fassel-type torch.

  17. UTILIZATION OF WASTE PLASTIC BOTTLES IN ASPHALT MIXTURE

    Directory of Open Access Journals (Sweden)

    TAHER BAGHAEE MOGHADDAM

    2013-06-01

    Full Text Available Nowadays, large amounts of waste materials are being produced in the world. One of the waste materials is plastic bottle. Generating disposable plastic bottles is becoming a major problem in many countries. Using waste plastic as a secondary material in construction projects would be a solution to overcome the crisis of producing large amount of waste plastics in one hand and improving the structure’s characteristics such as resistance against cracking on the other hand. This study aimed to investigate the effects of adding plastic bottles in road pavement. Marshall properties as well as specific gravity of asphalt mixture containing different percentages of plastic bottles were evaluated. Besides, Optimum Asphalt Content (OAC was calculated for each percentages of plastic bottles used in the mix. The stiffness and fatigue characteristics of mixture were assessed at OAC value. Results showed that the stability and flow values of asphalt mixture increased by adding waste crushed plastic bottle into the asphalt mixture. Further, it was shown that the bulk specific gravity and stiffness of mixtures increased by adding lower amount of plastic bottles; however, adding higher amounts of plastic resulted in lower specific gravity and mix stiffness. In addition, it was concluded that the mixtures containing waste plastic bottles have lower OAC values compared to the conventional mixture, and this may reduce the amount of asphalt binder can be used in road construction projects. Besides, the mixtures containing waste plastic showed significantly greater fatigue resistance than the conventional mixture.

  18. Vorticity transport in shock driven plasma flows: A comparison of MHD and two-fluid models

    Science.gov (United States)

    Bond, Daryl; Wheatley, Vincent; Pullin, Dale; Samtaney, Ravi

    2015-11-01

    Suppression of the Richtmyer-Meshkov instability in a plasma, through the application of a seed magnetic field, has been studied in the framework of ideal magnetohydrodymanics. These studies have shown that suppression is achieved through the transport of vorticity by magnetohydrodynamic waves away from a perturbed fluid-fluid interface where it was baroclinically generated by shock impact. The implementation of a more physically accurate, fully electromagnetic, two-fluid plasma representation allows a more realistic investigation of vorticity transport in shock driven plasma flows. Results comparing ideal one-dimensional two-fluid and magnetohydrodymanic flows are presented. Substantial increases in the complexity of the flow field and vorticity transport dynamics are observed with important ramifications for the stabilization of shock driven interfaces. This work was partially supported by the KAUST Office of Sponsored Research under Award URF/1/2162-01.

  19. BOTTLE MATERIAL AND CLEANSING PROCEDURES OF INFANT FEEDING BOTTLES.

    Science.gov (United States)

    Kuan, Wen-Hui; Chen, Yi-Lang

    2016-01-01

    The cleanliness of feeding bottles is vital for child health. Although machine cleansing of bottles in the food industry has been established, mechanical and manual cleansing methods are highly variable. This study was undertaken to determine the differences in the cleanliness of bottles that were cleaned using various combinations of bottle materials [glass and polypropylene (PP)], rinsing water volumes (1/3, 1/2, and 2/3 capacity of a bottle), and sustained shaking times (5 seconds and 20 seconds). Total organic carbon (TOC) and conductivity measurements were respectively used to evaluate the rinsed quantities of organic and inorganic formula residue from feeding bottles. The results indicated that glass bottles filled with rinsing water to 2/3 of their capacity showed the most efficient cleansing performance. However, the PP bottles exhibited a relatively poor cleansing result, particularly for organic cleanliness. The organic residue tends to accumulate on the PP bottle interior because of the aggregation of compounds with similar properties. The shaking time hardly influenced the cleanliness. The glass bottle was superior to the PP bottle in both organic and inorganic cleanliness, and organic constituents were more difficult to rinse from the bottle than the inorganic constituents were.

  20. Measurement of Plasma Ion Temperature and Flow Velocity from ...

    Indian Academy of Sciences (India)

    Abstract. The distinction between Doppler broadening and Doppler shift has been analysed, the differences between Gaussian fitting and the distribution of chord-integral line shape have also been discussed. Local ion temperature and flow velocity have been derived from the chord-averaged emission line profile by a ...

  1. Calculation of sheath and wake structure about a pillbox-shaped spacecraft in a flowing plasma

    Science.gov (United States)

    Parker, L. W.

    1977-01-01

    A computer program was used for studies of the disturbed zones around bodies in flowing plasmas, particularly spacecraft and their associated sheaths and wakes. The program solved a coupled Poisson-Vlasov system of nonlinear partial differential integral equations to obtain distributions of electric potential and ion and electron density about a finite length cylinder in a plasma flow at arbitrary ion Mach numbers. The approach was applicable to a larger range of parameters than other available approaches. In sample calculations, bodies up to 100 Debye lengths in radius were treated, that is, larger than any previously treated realistically. Applications were made to in-situ satellite experiments.

  2. Progress towards experimental realization of extreme-velocity flow-dominated magnetized plasmas

    Science.gov (United States)

    Weber, T. E.; Adams, C. S.; Welch, D. R.; Kagan, G.; Bean, I. A.; Henderson, B. R.; Klim, A. J.

    2017-10-01

    Interactions of flow-dominated plasmas with other plasmas, neutral gases, magnetic fields, solids etc., take place with sufficient velocity that kinetic energy dominates the dynamics of the interaction (as opposed to magnetic or thermal energy, which dominates in most laboratory plasma experiments). Building upon progress made by the Magnetized Shock Experiment (MSX) at LANL, we are developing the experimental and modeling capability to increase our ultimate attainable plasma velocities well in excess of 1000 km/s. Ongoing work includes designing new pulsed power switches, triggering, and inductive adder topologies; development of novel high-speed optical diagnostics; and exploration of new numerical techniques to specifically model the unique physics of translating/stagnating flow-dominated plasmas. Furthering our understanding of the physical mechanisms of energy conversion from kinetic to other forms, such as thermal energy, non-thermal tails/accelerated populations, enhanced magnetic fields, and radiation (both continuum and line), has wide-ranging significance in basic plasma science, astrophysics, and plasma technology applications such as inertial confinement fusion and intense radiation sources. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration. LA-UR-17-25786.

  3. MHD equilibrium of toroidal fusion plasma with stationary flows; Rownowaga MHD toroidalnej plazmy termojadrowej z przeplywami

    Energy Technology Data Exchange (ETDEWEB)

    Galkowski, A. [Institute of Atomic Energy, Otwock-Swierk (Poland)

    1994-12-31

    Non-linear ideal MHD equilibria in axisymmetric system with flows are examined, both in 1st and 2nd ellipticity regions. Evidence of the bifurcation of solutions is provided and numerical solutions of several problems in a tokamak geometry are given, exhibiting bifurcation phenomena. Relaxation of plasma in the presence of zero-order flows is studied in a realistic toroidal geometry. The field aligned flow allows equilibria with finite pressure gradient but with homogeneous temperature distribution. Numerical calculations have been performed for the 1st and 2nd ellipticity regimes of the extended Grad-Shafranov-Schlueter equation. Numerical technique, alternative to the well-known Grad`s ADM methods has been proposed to deal with slow adiabatic evolution of toroidal plasma with flows. The equilibrium problem with prescribed adiabatic constraints may be solved by simultaneous calculations of flux surface geometry and original profile functions. (author). 178 refs, 37 figs, 5 tabs.

  4. Observation of ion-cyclotron-frequency mode-conversion flow drive in tokamak plasmas.

    Science.gov (United States)

    Lin, Y; Rice, J E; Wukitch, S J; Greenwald, M J; Hubbard, A E; Ince-Cushman, A; Lin, L; Porkolab, M; Reinke, M L; Tsujii, N

    2008-12-05

    Strong toroidal flow (Vphi) and poloidal flow (Vtheta) have been observed in D-3He plasmas with ion cyclotron range of frequencies (ICRF) mode-conversion (MC) heating on the Alcator C-Mod tokamak. The toroidal flow scales with the rf power Prf (up to 30 km/s per MW), and is significantly larger than that in ICRF minority heated plasmas at the same rf power or stored energy. The central Vphi responds to Prf faster than the outer regions, and the Vphi(r) profile is broadly peaked for r/a or =1.5 MW and increases with power (up to 0.7 km/s per MW). The experimental evidence together with numerical wave modeling suggests a local flow drive source due to the interaction between the MC ion cyclotron wave and 3He ions.

  5. Energy implications of bottled water

    Science.gov (United States)

    Gleick, P. H.; Cooley, H. S.

    2009-01-01

    As bottled water use continues to expand around the world, there is growing interest in the environmental, economical, and social implications of that use, including concerns about waste generation, proper use of groundwater, hydrologic effects on local surface and groundwater, economic costs, and more. A key concern is how much energy is required to produce and use bottled water. This paper estimates the energy footprint required for various phases of bottled water production, transportation, and use. We do not develop a single comprehensive life-cycle energy estimate because of differences among water sources, bottling processes, transportation costs, and other factors, but we quantify key energy inputs necessary for site-specific assessments. We also apply these inputs to three site-specific examples of the energy required from production to the point of use: local bottled water produced and used in Los Angeles, water bottled in the South Pacific and shipped by cargo ship to Los Angeles, and water bottled in France and shipped in various ways to Los Angeles. For water transported short distances, the energy requirements of bottled water are dominated by the energy used to produce the plastic bottles. Long-distance transport, however, can lead to energy costs comparable to, or even larger than, those of producing the bottle. All other energy costs—for processing, bottling, sealing, labeling, and refrigeration—are far smaller than those for the production of the bottle and transportation. These data can be used to generate specific estimates for different sources, treatments, and delivery options.

  6. Optimization of plasma sampling depth and aerosol gas flow rates for single particle inductively coupled plasma mass spectrometry analysis.

    Science.gov (United States)

    Kálomista, Ildikó; Kéri, Albert; Galbács, Gábor

    2017-09-01

    We performed experiments to assess the separate and also the combined effect of the sampling depth and the aerosol gas flow rates on the signal formation in single particle inductively coupled plasma mass spectrometry (spICP-MS) measurements by using dispersions containing Ag and Au NPs. It was found that the NP signal can significantly be improved by the optimization of the sampling depth. With respect to the "robust" setting, a signal improvement of nearly 100% could be achieved, which translates into a 25-30% improvement in size detection limits. It was also found that the shape of the spICP-MS signal histograms also change with the change of the plasma sampling depth. It was demonstrated that nanoparticle peak separation can also be significantly enhanced by using sampling depth optimization. The effect of the aerosol dilution gas flow, now standard in most ICP-MS instruments, on the spICP-MS signal formation was also studied for the first time in the literature, as this flow was hoped to make spICP-MS measurements more practical and faster via the on-line dilution of the aerosol generated from nano-dispersions. Our experimental results revealed that the dilution gas flow can only be used for a moderate aerosol dilution in spICP-MS measurements, if the gas flow going to the pneumatic nebulizer is proportionally lowered at the same time. This however was found to cause a significant worsening in the operation of the sample introduction system, which gives rise to a strong NP signal loss. Thus it was concluded that the use of the aerosol dilution gas flow, in its present form, can not be suggested for spICP-MS analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Parameters of the plasma of a dc pulsating discharge in a supersonic air flow

    Energy Technology Data Exchange (ETDEWEB)

    Shibkov, V. M., E-mail: shibkov@phys.msu.ru; Shibkova, L. V.; Logunov, A. A. [Moscow State University, Faculty of Physics (Russian Federation)

    2017-03-15

    A dc discharge in a cold (T = 200 K) supersonic air flow at a static pressure of 200–400 Torr was studied experimentally. The excited unsteady pulsating discharge has the form of a thin plasma channel with a diameter of ≤1 mm, stretched downstream the flow. Depending on the discharge current, the pulsation frequency varies from 800 to 1600 Hz and the electron temperature varies from 8000 to 15000 K.

  8. Plasma flow during the brightening of proton aurora in the cusp

    DEFF Research Database (Denmark)

    Taguchi, S.; Hosokawa, K.; Suzuki, S.

    2010-01-01

    On the basis of simultaneous observations from the Super Dual Auroral Radar Network (SuperDARN), the far ultraviolet instrument on the IMAGE spacecraft, and a magnetometer installed on the east coast of Greenland, we present the characteristics of plasma flow during a westward moving proton auror...... to the traveling bulge at the polar cap boundary, which is the footprint of a flux transfer event, and imply that the preexisting vortical flow may be intensified when it becomes inflow to the bulge....

  9. Heat flow in variable polarity plasma arc welds

    Science.gov (United States)

    Abdelmessih, Amanie N.

    1992-01-01

    The space shuttle external tank and the space station Freedom are fabricated by the variable polarity plasma arc (VPPA) welding. Heat sink effects (taper) are observed when there are irregularities in the work-piece configuration especially if these irregularities are close to the weld bead. These heat sinks affect the geometry of the weld bead, and in extreme cases they could cause defects such as incomplete fusion. Also, different fixtures seem to have varying heat sink effects. The objective of the previous, present, and consecutive research studies is to investigate the effect of irregularities in the work-piece configuration and fixture differences on the weld bead geometry with the ultimate objective to compensate automatically for the heat sink effects and achieve a perfect weld.

  10. Electric and thermodynamic properties of plasma flows created by a magnetoplasma compressor

    Energy Technology Data Exchange (ETDEWEB)

    Puric, J [Faculty of Physics, University of Belgrade, POB 368, 11001 Belgrade (Serbia and Montenegro); Dojcinovic, I P [Faculty of Physics, University of Belgrade, POB 368, 11001 Belgrade (Serbia and Montenegro); Astashynski, V M [Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, F. Scaryny pr. 70, 220072 Minsk (Belarus); Kuraica, M M [Faculty of Physics, University of Belgrade, POB 368, 11001 Belgrade (Serbia and Montenegro); Obradovic, B M [Faculty of Physics, University of Belgrade, POB 368, 11001 Belgrade (Serbia and Montenegro)

    2004-02-01

    A magnetoplasma compressor of compact geometry (MPC-CG) with a semi-transparent electrode system that operates in the ion current transfer regime was constructed and studied. The electric and thermodynamic parameters of the discharge and the plasma flow created in different gases and their mixtures (hydrogen, nitrogen, argon and Ar + 3% H{sub 2}) have been measured to optimize the working conditions within the 100-3000 Pa pressure range for input energy up to 6.4 kJ. A special construction of the accelerator electrode system shielded by the self-magnetic field results in protection from erosion, which is the main cause of the high current cut-off in conventional plasma accelerators. It was found that the compression plasma flow velocity, electron density and temperature predominantly depend on the energy conversion rate from the energy supply to the plasma, since the current cut-off is avoided. The maximum energy conversion rate for MPC-CG was found when operating in hydrogen. The plasma flow velocity and electron density maximum values are measured close to 100 km s{sup -1} and 10{sup 17} cm{sup -3}, respectively, for input energy of 6.4 kJ at 1000 Pa pressure in hydrogen. Our results appear in good agreement with existing theoretical and experimental data.

  11. Electric and thermodynamic properties of plasma flows created by a magnetoplasma compressor

    Science.gov (United States)

    Puric, J.; Dojcinovic, I. P.; Astashynski, V. M.; Kuraica, M. M.; Obradovic, B. M.

    2004-02-01

    A magnetoplasma compressor of compact geometry (MPC-CG) with a semi-transparent electrode system that operates in the ion current transfer regime was constructed and studied. The electric and thermodynamic parameters of the discharge and the plasma flow created in different gases and their mixtures (hydrogen, nitrogen, argon and Ar + 3% H2) have been measured to optimize the working conditions within the 100-3000 Pa pressure range for input energy up to 6.4 kJ. A special construction of the accelerator electrode system shielded by the self-magnetic field results in protection from erosion, which is the main cause of the high current cut-off in conventional plasma accelerators. It was found that the compression plasma flow velocity, electron density and temperature predominantly depend on the energy conversion rate from the energy supply to the plasma, since the current cut-off is avoided. The maximum energy conversion rate for MPC-CG was found when operating in hydrogen. The plasma flow velocity and electron density maximum values are measured close to 100 km s-1 and 1017 cm-3, respectively, for input energy of 6.4 kJ at 1000 Pa pressure in hydrogen. Our results appear in good agreement with existing theoretical and experimental data.

  12. Techno-economic packaging of palm wine preservation and bottling ...

    African Journals Online (AJOL)

    Production cost estimate varies between N37.85/bottle (60cl) in the first year and N35.37/bottle (60cl) in the fifth year. The annual net profits are N8, 460,430.00 and N12, 025,710.00 in years one and five respectively. Projected cash flow is positive in year one i.e. N5,329,960.00 while the projected balance sheet shows that ...

  13. Variational principles and Lyapunov stability analysis for compressible cylindrical plasma flows with arbitrary cross-section

    Energy Technology Data Exchange (ETDEWEB)

    Khater, A H; Moawad, S M [Department of Mathematics, Faculty of Science, Cairo University, Beni-Suef (Egypt)

    2003-03-01

    The equilibrium and stability properties of ideal compressible magnetohydrodynamic (MHD) flows are investigated. The domain is taken to be cylindrical with arbitrary cross-section. Variational principles for plasma equilibria with mass flow are formulated, where we associate the cylindrical MHD equilibrium states to critical points of a conserved Lyapunov functional. This functional consists of the sum of the total energy, the mass, the circulation along field lines (cross-helicity), the momentum and the magnetic helicity. Lyapunov stability conditions for compressible cylindrical ideal MHD flows with arbitrary cross-section are determined.

  14. Modification of SrTiO3 single-crystalline surface after plasma flow treatment

    Energy Technology Data Exchange (ETDEWEB)

    Levin, Alexandr A.; Weissbach, Torsten; Leisegang, Tilmann; Meyer, Dirk C. [Institut fuer Strukturphysik, Technische Universitaet Dresden, 01062 Dresden (Germany); Kulagin, Nikolay A. [Kharkiv National University for Radioelectronics, av. Shakespeare 6-48, 61045 Kharkiv (Ukraine); Langer, Enrico [Institut fuer Festkoerperphysik, Technische Universitaet Dresden, 01062 Dresden (Germany)

    2009-07-01

    Surface of pure and transition metal-doped SrTiO3(STO) single crystals before and after hydrogen plasma-flow treatment (energy of 5..20 J/cm2) is investigated by wide-angle X-ray diffraction (WAXRD), fluorescence X-ray absorption near edge structure (XANES) and scanning electron microscopy (SEM) techniques. Plasma treatment results in the formation of a textured polycrystalline layer at the surface of the single-crystalline samples with different orientation. The formation of the quasi-ordered structures consisting of nanoscale-sized pyramids is observed by SEM. XANES evidences the change of the valency of the part of Ti4+ to Ti3+ due to the plasma treatment. The data obtained together with results of X-ray spectroscopy measurements gives evidences of the change of stoichiometry of the STO samples resulting in a change of their physical properties after plasma treatment.

  15. Formation of thermal flow fields and chemical transport in air and water by atmospheric plasma

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Tetsuji; Morfill, Gregor E [Max-Planck Institute for Extraterrestrial Physics, 85748 Garching (Germany); Iwafuchi, Yutaka [Graduate School of Engineering, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 9808577 (Japan); Sato, Takehiko, E-mail: sato@ifs.tohoku.ac.jp [Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 9808577 (Japan)

    2011-05-15

    Cold atmospheric plasma is a potential tool for medical purposes, e.g. disinfection/sterilization. In order for it to be effective and functional, it is crucial to understand the transport mechanism of chemically reactive species in air as well as in liquid. An atmospheric plasma discharge was produced between a platinum pin electrode and the surface of water. The thermal flow field of a cold atmospheric plasma as well as its chemical components was measured. A gas flow with a velocity of around 15 m s{sup -1} to the water's surface was shown to be induced by the discharge. This air flow induced a circulating flow in the water from the discharge point at the water's surface because of friction. It was also demonstrated that the chemical components generated in air dissolved in water and the properties of the water changed. The reactive species were believed to be distributed mainly by convective transport in water, because the variation in the pH profile indicated by a methyl red solution resembled the induced flow pattern.

  16. Effects of Gas Flow Rate on the Discharge Characteristics of a DC Excited Plasma Jet

    Science.gov (United States)

    Li, Xuechen; Jia, Pengying; Di, Cong; Bao, Wenting; Zhang, Chunyan

    2015-09-01

    A direct current (DC) source excited plasma jet consisting of a hollow needle anode and a plate cathode has been developed to form a diffuse discharge plume in ambient air with flowing argon as the working gas. Using optical and electrical methods, the discharge characteristics are investigated for the diffuse plasma plume. Results indicate that the discharge has a pulse characteristic, under the excitation of a DC voltage. The discharge pulse corresponds to the propagation process of a plasma bullet travelling from the anode to the cathode. It is found that, with an increment of the gas flow rate, both the discharge plume length and the current peak value of the pulsed discharge decrease in the laminar flow mode, reach their minima at about 1.5 L/min, and then slightly increase in the turbulent mode. However, the frequency of the pulsed discharge increases in the laminar mode with increasing the argon flow rate until the argon flow rate equals to about 1.5 L/min, and then slightly decreases in the turbulent mode. supported by National Natural Science Foundation of China (Nos. 10805013, 11375051), Funds for Distinguished Young Scientists of Hebei Province, China (No. A2012201045), Department of Education for Outstanding Youth Project of China (No. Y2011120), and Youth Project of Hebei University of China (No. 2011Q14)

  17. Emergence and decay rate of the edge plasma flow shear near a critical transition

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, J M; Garcia, L [Universidad Carlos III, 28911 Leganes, Madrid (Spain); Carreras, B A [BACV Solutions, Inc, Oak Ridge, Tennessee 37830 (United States)], E-mail: jmdelgad@fis.uc3m.es

    2009-01-15

    Recently, the experimental results for the emergence of the plasma shear flow layer in TJ-II have been explained as a second-order phase transition like process by using a simple model of envelope equations for the fluctuation level, the averaged poloidal velocity shear and the pressure gradient (2006 Phys. Plasmas 13 122509). Here, we extend this model by incorporating radial coupling. The model is applied to the study of the turbulence-shear flow interaction when the energy flux is low. Transition dynamics and their concomitant thresholds are examined within the context of this model. The effect of an external torque induced by electrode biasing has also been considered. In particular, we analyze the decay rate of the shear flow after switching off the biasing.

  18. A large-scale flow vortex in the Venus plasma tail and its fluid dynamic interpretation

    Science.gov (United States)

    Lundin, R.; Barabash, S.; Futaana, Y.; HolmströM, M.; Perez-De-Tejada, H.; Sauvaud, J.-A.

    2013-04-01

    We report on the existence of a large-scale ion flow vortex, a curled tailward flow of solar wind H+ (SW H+), and ionospheric O+ in the Venus plasma tail. The vortex commences at dusk (-Y), driven by a transverse (to the solar wind) aberration flow component. Dusk magnetosheath and ionospheric ions move westward across the nightside into the dawn sector, from where the tailward and lateral flow merges into a tailward-moving vortex. A fluid analysis of the SW H+ energy and momentum (E&M) transfer to O+ at the terminator, shows that E&M balance (efficiency ≈1) is achieved in the altitude range of 1200-600 km. Below 600 km a westward O+ flow, moving along the direction of the atmospheric superrotation, dominates. Conversely, SW H+ dominates the high-altitude vortex. The Venus large-scale tail vortex is hardly unique. Other gaseous celestial objects (comets) orbiting the Sun may develop similar tail vortices.

  19. Numerical simulation of nonequilibrium inductive plasma flow coupled with electromagnetic field calculation

    Science.gov (United States)

    Yu, Minghao; Takahashi, Yusuke; Kihara, Hisashi; Abe, Ken-ichi; Yamada, Kazuhiko; Abe, Takashi

    2014-12-01

    Numerical investigation of nonequilibrium inductively coupled plasma (ICP) flow was carried out to study the physical properties of the flow inside a 10-kW ICP torch with the working gas being nitrogen. The flow field was described by two-dimensional compressible axisymmetric Navier-Stokes (N-S) equations that took into account 5 species and 8 chemical reactions. The magnetic vector-potential equations were tightly coupled with the flow-field equations to describe the heating process by inductive discharge. A four-temperature model was adopted to model thermal nonequilibrium process in the discharge torch. The characteristics of ICP flow such as thermal nonequilibrium, inductive discharge, and strong effects of Lorentz forces became clear through the present study.

  20. Time-resolved Spectroscopy of a Sheared Flow Stabilized Z-pinch Plasma

    Science.gov (United States)

    Forbes, Eleanor

    2016-10-01

    The ZaP Flow Z-pinch Project investigates the use of sheared-axial flows to stabilize an otherwise unstable plasma configuration. Diagnostics with sub-microsecond resolution are required to obtain accurate time-resolved data since the plasma pulse is approximately 100 μs. Analyzing the Doppler shift of impurity line radiation from the pinch provides a measure of the velocity profile and is a reliable method of determining the plasma sheared flow. The velocity profile is spatially resolved through the use of a 20-chord fiber bundle. The ZaP-HD experiment has used a PI-MAX intensified CCD array to record a single time-resolved spectrum per plasma pulse. Obtaining the evolution of the velocity profile using this method required spectra acquired over hundreds of pulses with identical initial parameters and varying acquisition times. The use of a Kirana 05M ultra-fast framing camera is investigated for recording time-resolved velocity profiles during a single pulse. The Kirana utilizes an ultraviolet intensifier to record 180 frames of UV light at up to 2 million frames per second. An ultraviolet optics system is designed to couple the exit port of an Acton SP-500i spectrometer to the Kirana UV intensifier and focus spectra at the camera detector plane. This work is supported by US DoE FES, NNSA, and ARPA-E ALPHA.

  1. Kinetic simulation technique for plasma flow in strong external magnetic field

    Science.gov (United States)

    Ebersohn, Frans H.; Sheehan, J. P.; Gallimore, Alec D.; Shebalin, John V.

    2017-12-01

    A technique for the kinetic simulation of plasma flow in strong external magnetic fields was developed which captures the compression and expansion of plasma bound to a magnetic flux tube as well as forces on magnetized particles within the flux tube. This quasi-one-dimensional (Q1D) method resolves a single spatial dimension while modeling two-dimensional effects. The implementation of this method in a Particle-In-Cell (PIC) code was verified with newly formulated test cases which include two-particle motion and particle dynamics in a magnetic mirror. Results from the Q1D method and fully two dimensional simulations were compared and error analyses performed verifying that the Q1D model reproduces the fully 2D results in the correct regimes. The Q1D method was found to be valid when the hybrid Larmor radius was less than 10% of the magnetic field scale length for magnetic field guided plasma expansions and less than 1% of the magnetic field scale length for a plasma in a converging-diverging magnetic field. The simple and general Q1D method can readily be incorporated in standard 1D PIC codes to capture multi-dimensional effects for plasma flow along magnetic fields in parameter spaces currently inaccessible by fully kinetic methods.

  2. A key inactivation factor of HeLa cell viability by a plasma flow

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Takehiko; Yokoyama, Mayo [Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Johkura, Kohei, E-mail: sato@ifs.tohoku.ac.jp [Department of Histology and Embryology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621 (Japan)

    2011-09-21

    Recently, a plasma flow has been applied to medical treatment using effects of various kinds of stimuli such as chemical species, charged particles, heat, light, shock wave and electric fields. Among them, the chemical species are known to cause an inactivation of cell viability. However, the mechanisms and key factors of this event are not yet clear. In this study, we focused on the effect of H{sub 2}O{sub 2} in plasma-treated culture medium because it is generated in the culture medium and it is also chemically stable compared with free radicals generated by the plasma flow. To elucidate the significance of H{sub 2}O{sub 2}, we assessed the differences in the effects of plasma-treated medium and H{sub 2}O{sub 2}-added medium against inactivation of HeLa cell viability. These two media showed comparable effects on HeLa cells in terms of the survival ratios, morphological features of damage processes, permeations of H{sub 2}O{sub 2} into the cells, response to H{sub 2}O{sub 2} decomposition by catalase and comprehensive gene expression. The results supported that among chemical species generated in a plasma-treated culture medium, H{sub 2}O{sub 2} is one of the main factors responsible for inactivation of HeLa cell viability. (fast track communication)

  3. Pulmonary and heart diseases with inhalation of atmospheric pressure plasma flow

    Science.gov (United States)

    Hirata, Takamichi; Murata, Shigeru; Kishimoto, Takumi; Tsutsui, Chihiro; Kondo, Akane; Mori, Akira

    2012-10-01

    We examined blood pressure in the abdominal aorta of mini pig under plasma inhalation of atmospheric pressure plasma flow. The coaxial atmospheric pressure plasma source has a tungsten wire inside a glass capillary, that is surrounded by a grounded tubular electrode. Plasma was generated under the following conditions; applied voltage: 8 kVpp, frequency: 3 kHz, and helium (He) gas flow rate: 1 L/min. On the other hand, sphygmomanometry of a blood vessel proceeded using a device comprising a disposable force transducer, and a bedside monitor for simultaneous electrocardiography and signal pressure measurements. We directly measured Nitric oxide (NO) using a catheter-type NO sensor placed in the coronary sinus through an angiography catheter from the abdomen. Blood pressure decreased from 110/65 to 90/40 mm Hg in the animals in vivo under plasma inhalation. The NO concentration in the abdominal aorta like the blood pressure, reached a maximum value at about 40 s and then gradually decreased.

  4. Experimental investigation of flow induced dust acoustic shock waves in a complex plasma

    CERN Document Server

    Jaiswal, S; Sen, A

    2016-01-01

    We report on experimental observations of flow induced large amplitude dust-acoustic shock waves (DASW) in a complex plasma. The experiments have been carried out in a $\\Pi$ shaped DC glow discharge experimental device using kaolin particles as the dust component in a background of Argon plasma. A strong supersonic flow of the dust fluid is induced by adjusting the pumping speed and neutral gas flow into the device. An isolated copper wire mounted on the cathode acts as a potential barrier to the flow of dust particles. A sudden change of gas flow rate is used to trigger the onset of high velocity dust acoustic shocks whose dynamics are captured by fast video pictures of the evolving structures. The physical characteristics of these shocks are delineated through a parametric scan of their dynamical properties over a range of flow speeds and potential hill heights. The observed evolution of the shock waves and their propagation characteristics are found to compare well with model numerical results based on a m...

  5. Experimental investigation of flow induced dust acoustic shock waves in a complex plasma

    Energy Technology Data Exchange (ETDEWEB)

    Jaiswal, S., E-mail: surabhijaiswal73@gmail.com; Bandyopadhyay, P.; Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2016-08-15

    We report on experimental observations of flow induced large amplitude dust-acoustic shock waves in a complex plasma. The experiments have been carried out in a Π shaped direct current glow discharge experimental device using kaolin particles as the dust component in a background of Argon plasma. A strong supersonic flow of the dust fluid is induced by adjusting the pumping speed and neutral gas flow into the device. An isolated copper wire mounted on the cathode acts as a potential barrier to the flow of dust particles. A sudden change in the gas flow rate is used to trigger the onset of high velocity dust acoustic shocks whose dynamics are captured by fast video pictures of the evolving structures. The physical characteristics of these shocks are delineated through a parametric scan of their dynamical properties over a range of flow speeds and potential hill heights. The observed evolution of the shock waves and their propagation characteristics are found to compare well with model numerical results based on a modified Korteweg-de-Vries-Burgers type equation.

  6. Plasma-based actuators for turbulent boundary layer control in transonic flow

    Science.gov (United States)

    Budovsky, A. D.; Polivanov, P. A.; Vishnyakov, O. I.; Sidorenko, A. A.

    2017-10-01

    The study is devoted to development of methods for active control of flow structure typical for the aircraft wings in transonic flow with turbulent boundary layer. The control strategy accepted in the study was based on using of the effects of plasma discharges interaction with miniature geometrical obstacles of various shapes. The conceptions were studied computationally using 3D RANS, URANS approaches. The results of the computations have shown that energy deposition can significantly change the flow pattern over the obstacles increasing their influence on the flow in boundary layer region. Namely, one of the most interesting and promising data were obtained for actuators basing on combination of vertical wedge with asymmetrical plasma discharge. The wedge considered is aligned with the local streamlines and protruding in the flow by 0.4-0.8 of local boundary layer thickness. The actuator produces negligible distortion of the flow at the absence of energy deposition. Energy deposition along the one side of the wedge results in longitudinal vortex formation in the wake of the actuator providing momentum exchange in the boundary layer. The actuator was manufactured and tested in wind tunnel experiments at Mach number 1.5 using the model of flat plate. The experimental data obtained by PIV proved the availability of the actuator.

  7. Characterization of SOL plasma flows and potentials in ICRF-heated plasmas in Alcator C-mod

    Science.gov (United States)

    Hong, R.; Wukitch, S. J.; Lin, Y.; Terry, J. L.; Cziegler, I.; Reinke, M. L.; Tynan, G. R.

    2017-10-01

    Gas-puff imaging techniques are employed to determine the far SOL region radial electric field and the plasma potential in ICRF heated discharges in the Alcator C-Mod tokamak. The two-dimensional velocity fields of the turbulent structures, which are advected by RF-induced {E}× {B} flows, are obtained via the time-delay estimation (TDE) techniques. Both the magnitude and radial extension of the radial electric field E r are observed to increase with the toroidal magnetic field strength B φ and the ICRF power. In particular, the RF-induced E r extends from the vicinity of the ICRF antenna to the separatrix when {B}\\varphi =7.9 {{T}} and {P}{ICRF}≳ 1 {MW}. In addition, low-Z impurity seeding near the antenna is found to substantially reduce the sheath potential associated with ICRF power. The TDE techniques have also been used to revisit and estimate ICRF-induced potentials in different antenna configurations: (1) conventional toroidally aligned (TA) antenna versus field-aligned (FA) antenna; (2) FA monopole versus FA dipole. It shows that FA and TA antennas produce similar magnitude of plasma potentials, and the FA monopole induced greater potential than the FA dipole phasing. The TDE estimations of RF-induced plasma potentials are consistent with previous results based on the poloidal phase velocity.

  8. Monitoring Temperature in High Enthalpy Arc-heated Plasma Flows using Tunable Diode Laser Absorption Spectroscopy

    Science.gov (United States)

    Martin, Marcel Nations; Chang, Leyen S.; Jeffries, Jay B.; Hanson, Ronald K.; Nawaz, Anuscheh; Taunk, Jaswinder S.; Driver, David M.; Raiche, George

    2013-01-01

    A tunable diode laser sensor was designed for in situ monitoring of temperature in the arc heater of the NASA Ames IHF arcjet facility (60 MW). An external cavity diode laser was used to generate light at 777.2 nm and laser absorption used to monitor the population of electronically excited oxygen atoms in an air plasma flow. Under the assumption of thermochemical equilibrium, time-resolved temperature measurements were obtained on four lines-of-sight, which enabled evaluation of the temperature uniformity in the plasma column for different arcjet operating conditions.

  9. Adsorption of proteins out of plasma onto glass from a separated flow.

    Science.gov (United States)

    Leduc, C; Depaola, N; Konath, S; Vroman, L; Leonard, E F

    1994-01-01

    Perturbations in the adsorption of plasma proteins caused by flow separation were studied quantitatively. An instrument was constructed that causes flow to separate over approximately half the width of a standard microscope slide and the pattern of protein deposition in and near the separated flow was observed by staining the slide with black iron oxide. The slide was mounted at the edge of a Couette flow field established between two concentric cylinders, the outer of which was rotating. The slide was located on the stationary, inner cylinder just downstream of a rectangular bar that causes the flow to separate. After exposure to dilute plasma injected upstream of the bar, the slide was removed and stained with oxide suspension. The resulting, visible pattern was scanned through a video camera and analyzed to yield relative values of stain density that could be quantified. The oxide patterns suggest that proteins were deposited onto the slide less rapidly in and just downstream of the separated flow region than farther downstream. At a shear rate of 6.61 s-1, corresponding to a velocity of 1.32 cm s-1 0.2 cm above the point of flow separation, overall amounts of adsorbed proteins increased with exposure time in the range 3-30 min with the exception of a period from 10 to 11 min when all data show a temporary decrease. In calibration experiments, oxide failed to adhere to slides exposed to purified albumin but adhered copiously to slides exposed to purified fibrinogen. These results suggest that the oxide patterns following plasma exposure are attributable primarily to fibrinogen and that the temporary decrease in the separated flow experiments is attributable to the displacement of fibrinogen by a less stainable protein, conjecturally high molecular weight kininogen and factor XII. This study yields quantitative information confirming earlier findings that were less controlled and non-quantitative. It confirms the hypothesis that the sequence of protein deposition

  10. 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

  11. Flow at the SPS and RHIC as a quark-gluon plasma signature.

    Science.gov (United States)

    Teaney, D; Lauret, J; Shuryak, E V

    2001-05-21

    Radial and elliptic flow in noncentral heavy-ion collisions can constrain the effective equation of state (EOS) of the excited nuclear matter. To this end, a model combining relativistic hydrodynamics and a hadronic transport code [Sorge, Phys. Rev. C 52, 3291 (1995)] is developed. For an EOS with a first-order phase transition, the model reproduces both the radial and elliptic flow data at the SPS. With the EOS fixed from SPS data, we quantify predictions at RHIC where the quark-gluon plasma (QGP) pressure is expected to drive additional radial and elliptic flows. Currently, the strong elliptic flow observed in the first RHIC measurements does not conclusively signal this nascent QGP pressure.

  12. Localization of Short-Chain Polyphosphate Enhances its Ability to Clot Flowing Blood Plasma

    Science.gov (United States)

    Yeon, Ju Hun; Mazinani, Nima; Schlappi, Travis S.; Chan, Karen Y. T.; Baylis, James R.; Smith, Stephanie A.; Donovan, Alexander J.; Kudela, Damien; Stucky, Galen D.; Liu, Ying; Morrissey, James H.; Kastrup, Christian J.

    2017-02-01

    Short-chain polyphosphate (polyP) is released from platelets upon platelet activation, but it is not clear if it contributes to thrombosis. PolyP has increased propensity to clot blood with increased polymer length and when localized onto particles, but it is unknown whether spatial localization of short-chain polyP can accelerate clotting of flowing blood. Here, numerical simulations predicted the effect of localization of polyP on clotting under flow, and this was tested in vitro using microfluidics. Synthetic polyP was more effective at triggering clotting of flowing blood plasma when localized on a surface than when solubilized in solution or when localized as nanoparticles, accelerating clotting at 10-200 fold lower concentrations, particularly at low to sub-physiological shear rates typical of where thrombosis occurs in large veins or valves. Thus, sub-micromolar concentrations of short-chain polyP can accelerate clotting of flowing blood plasma under flow at low to sub-physiological shear rates. However, a physiological mechanism for the localization of polyP to platelet or vascular surfaces remains unknown.

  13. Flow separation control on swept wing with nanosecond pulse driven DBD plasma actuators

    Directory of Open Access Journals (Sweden)

    Zhao Guangyin

    2015-04-01

    Full Text Available A 15° swept wing with dielectric barrier discharge plasma actuator is designed. Experimental study of flow separation control with nanosecond pulsed plasma actuation is performed at flow velocity up to 40 m/s. The effects of the actuation frequency and voltage on the aerodynamic performance of the swept wing are evaluated by the balanced force and pressure measurements in the wind tunnel. At last, the performances on separation flow control of the three types of actuators with plane and saw-toothed exposed electrodes are compared. The optimal actuation frequency for the flow separation control on the swept wing is detected, namely the reduced frequency is 0.775, which is different from 2-D airfoil separation control. There exists a threshold voltage for the low swept wing flow control. Before the threshold voltage, as the actuation voltage increases, the control effects become better. The maximum lift is increased by 23.1% with the drag decreased by 22.4% at 14°, compared with the base line. However, the best effects are obtained on actuator with plane exposed electrode in the low-speed experiment and the abilities of saw-toothed actuators are expected to be verified under high-speed conditions.

  14. Life time extension of quasi-stationary plasma flow from Magnetoplasma Compressor

    Science.gov (United States)

    Dojčinović, I. P.; Kuraica, M. M.; Astashynski, V. M.; Purić, J.

    2002-12-01

    Time extension of quasi-stationary plasma flows from Magnetoplasma Compressor (MPC) operating in nitrogen at 5 mbar pressure has been obtained and discussed. A condenser bank of 1200 μF charged up to 2.7, 3.2 and 4 kV has been used as energy supply and was realized as an adequate delay line using properly chosen inductivity of the coils inserted among the capacitors and the resistance of the connecting conductor line through an ignitron to MPC electrode system. It gives a possibility to enlarge several times the life times of the investigated compression plama flows from MPC under the same other experimental conditions.

  15. Symmetry breaking in MAST plasma turbulence due to toroidal flow shear

    CERN Document Server

    Fox, M F J; Field, A R; Ghim, Y -c; Parra, F I; Schekochihin, A A

    2016-01-01

    The flow shear associated with the differential toroidal rotation of tokamak plasmas breaks an underlying symmetry of the turbulent fluctuations imposed by the up-down symmetry of the magnetic equilibrium. Using experimental Beam-Emission-Spectroscopy (BES) measurements and gyrokinetic simulations, this symmetry breaking in ion-scale turbulence in MAST is shown to manifest itself as a tilt of the spatial correlation function and a finite skew in the distribution of the fluctuating density field. The tilt is a statistical expression of the "shearing" of the turbulent structures by the mean flow. The skewness of the distribution is related to the emergence of long-lived density structures in sheared, near-marginal plasma turbulence. The extent to which these effects are pronounced is argued (with the aid of the simulations) to depend on the distance from the nonlinear stability threshold. Away from the threshold, the symmetry is effectively restored.

  16. Bactericidal effect of plasma jet with helium flowing through 3% hydrogen peroxide against Enterococcus faecalis

    Science.gov (United States)

    Zhou, Xin-Cai; Li, Yu-Lan; Liu, De-Xi; Cao, Ying-Guang; Lu, Xin-Pei

    2016-01-01

    The aim of the present study was to assess the antimicrobial activity of plasma jet with helium (He) flowing through 3% hydrogen peroxide in root canals infected with Enterococcus faecalis. A total of 42 single-rooted anterior teeth were prepared, sterilized, inoculated with an E. faecalis suspension and incubated for 7 days. Next, the teeth were randomly divided into six experimental groups (including groups treated by plasma jet with or without He for different time durations) and one control group treated without plasma. The number of surviving bacteria in each canal was determined by counting the colony forming units (CFU)/ml on nutrient agar plates. The results indicated that statistically significant reduction in CFU/ml (Pfaecalis and should be considered as an alternative method for root canal disinfection in endodontic treatments. PMID:27882119

  17. Impurity transport and bulk ion flow in a mixed collisionality stellarator plasma

    Science.gov (United States)

    Newton, S. L.; Helander, P.; Mollén, A.; Smith, H. M.

    2017-10-01

    The accumulation of impurities in the core of magnetically confined plasmas, resulting from standard collisional transport mechanisms, is a known threat to their performance as fusion energy sources. Whilst the axisymmetric tokamak systems have been shown to benefit from the effect of temperature screening, that is an outward flux of impurities driven by the temperature gradient, impurity accumulation in stellarators was thought to be inevitable, driven robustly by the inward pointing electric field characteristic of hot fusion plasmas. We have shown in Helander et al. (Phys. Rev. Lett., vol. 118, 2017a, 155002) that such screening can in principle also appear in stellarators, in the experimentally relevant mixed collisionality regime, where a highly collisional impurity species is present in a low collisionality bulk plasma. Details of the analytic calculation are presented here, along with the effect of the impurity on the bulk ion flow, which will ultimately affect the bulk contribution to the bootstrap current.

  18. Preliminary investigation of power flow and electrode phenomena in a multi-megawatt coaxial plasma thruster

    Science.gov (United States)

    Schoenberg, Kurt; Gerwin, Richard; Henins, Ivars; Mayo, Robert; Scheuer, Jay; Nurden, Glen

    1993-01-01

    This paper summarizes preliminary experimental and theoretical research that was directed towards the study of quasisteady-state power flow in a large, un-optimized, multi-megawatt coaxial plasma thruster. The report addresses large coaxial thruster operation and includes evaluation and interpretation of the experimental results with a view to the development of efficient, steady-state megawatt-class magnetoplasmadynamic (MPD) thrusters.

  19. Multiparametric flow cytometry profiling of neoplastic plasma cells in multiple myeloma

    DEFF Research Database (Denmark)

    Johnsen, Hans Erik; Bøgsted, Martin; Klausen, Tobias W

    2010-01-01

    BACKGROUND AND AIM: The clinical impact of multiparametric flow cytometry (MFC) in multiple myeloma (MM) is still unclear and under evaluation. Further progress relies on multiparametric profiling of the neoplastic plasma cell (PC) compartment to provide an accurate image of the stage......, prognostic, and predictive information useful in clinical practice, which will be prospectively validated within the European Myeloma Network (EMN). © 2010 International Clinical Cytometry Society....

  20. Nicorandil improves myocardial function by regulating plasma nitric oxide and endothelin-1 in coronary slow flow

    Science.gov (United States)

    Chen, Xiuhua; Li, Shan; Huo, Xuezhen; Fu, Xiuxiu; Dong, Xiaonan

    2015-01-01

    Background Coronary slow flow (CSF) is a special coronary microvascular disorder. The pathogenesis and effective therapeutics of CSF remain unclear. This study aimed to evaluate the global and regional functions of the left ventricle (LV) and investigate the efficacy of nicorandil in patients with CSF. Patients and methods Thirty-six patients with CSF in the left anterior descending (LAD) branch and 20 patients with normal coronary arteries were included. Global and regional functions of the LV supplied by LAD were measured using conventional Doppler echocardiography and two-dimensional speckle tracking echocardiography, respectively, within 24 h after coronary angiography. Concentrations of plasma nitric oxide (NO) and endothelin-1 (ET-1) were detected using colorimetry and radioimmunoassay, respectively. The function of the LV and the levels of NO and ET-1 were also investigated before and 90 days after treatment with 15 mg/day of nicorandil. Results Compared with the control group, the early diastolic peak velocity (E), E/A ratio, and plasma NO levels were lower, whereas the late diastolic peak flow velocity (A) and plasma ET-1 levels were significantly higher in the CSF group (Pimprove chest pain symptoms and the impaired function of the LV, possibly by increasing plasma NO and reducing ET-1 in CSF. PMID:25325437

  1. Observation of magnetic field generation via the Weibel instability in interpenetrating plasma flows

    Energy Technology Data Exchange (ETDEWEB)

    Huntington, C. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fiuza, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ross, J. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zylstra, A. B. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States); Drake, R. P. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Atmospheric, Oceanic, and Space Sciences; Froula, D. H. [Univ. of Rochester, NY (United States). Physics Dept. and Lab. for Laser Energetics; Gregori, G. [Univ. of Oxford (United Kingdom). Dept. of Physics; Kugland, N. L. [Lam Research Corp., Fremont, CA (United States); Kuranz, C. C. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Atmospheric, Oceanic, and Space Sciences; Levy, M. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Li, C. K. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States); Meinecke, J. [Univ. of Oxford (United Kingdom). Dept. of Physics; Morita, T. [Osaka Univ. (Japan). Inst. of Laser Engineering; Petrasso, R. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States); Plechaty, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Remington, B. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ryutov, D. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sakawa, Y. [Osaka Univ. (Japan). Inst. of Laser Engineering; Spitkovsky, A. [Princeton Univ., NJ (United States). Dept. of Astrophysical Sciences; Takabe, H. [Osaka Univ. (Japan). Inst. of Laser Engineering; Park, H.-S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-01-19

    Collisionless shocks can be produced as a result of strong magnetic fields in a plasma flow, and therefore are common in many astrophysical systems. The Weibel instability is one candidate mechanism for the generation of su fficiently strong fields to create a collisionless shock. Despite their crucial role in astrophysical systems, observation of the magnetic fields produced by Weibel instabilities in experiments has been challenging. Using a proton probe to directly image electromagnetic fields, we present evidence of Weibel-generated magnetic fields that grow in opposing, initially unmagnetized plasma flows from laser-driven laboratory experiments. Three-dimensional particle-in-cell simulations reveal that the instability effi ciently extracts energy from the plasma flows, and that the self-generated magnetic energy reaches a few percent of the total energy in the system. Furthermore, this result demonstrates an experimental platform suitable for the investigation of a wide range of astrophysical phenomena, including collisionless shock formation in supernova remnants, large-scale magnetic field amplification, and the radiation signature from gamma-ray bursts.

  2. Plasma flow measurements in improved modes on STOR-M and CASTOR tokamaks

    Science.gov (United States)

    Germaine, G. S.; Xiao, C.; Hirose, A.

    2010-02-01

    A Gundestrup probe, a Mach probe array, is used to measure both the parallel and perpendicular flow velocities in the Saskatchewan Torus-Modified (STOR-M) tokamak during several discharge conditions. It is observed that during ohmic discharges there is no velocity shear and the direction of the parallel flow is independent of the direction of the toroidal magnetic field. During H-mode induced by a turbulent heating current pulse, a region of strong velocity shear develops in the plasma edge and an edge transport barrier develops. This results in a short period of improved particle and energy confinement with reduced fluctuation amplitudes. During electrode biasing experiments, a stainless steel biasing electrode is inserted into the plasma up to r=82 mm and biased to+500 V relative to the vacuum chamber. It is observed that the particle confinement improves during the biasing phase while the energy confinement is degraded. A region of weak shear in the poloidal flow is observed in the plasma scrape-off layer (SOL). The results from STOR-M are compared with results from data taken in the Czech Academy of Sciences Torus (CASTOR) tokamak during both ohmic discharges and discharges with electrode biasing.

  3. The investigation of heterogeneous flow generated by the direct current plasma torch

    Science.gov (United States)

    Evmenchikov, N. L.; Penyazkov, O. G.; Shatan, I. N.

    2016-11-01

    In the article, the two-phase flow of electric arc gas heater of the linear scheme is studied. The power of the plasma torch can be varied from 200 to 1500 kW. For stabilization of the electric arc a magnetic coil is used. The operation of the plasma torch took place at overpressure in the discharge chamber. Injection of the powder was made near the exit of the nozzle. A powder of SiO2 was used as a disperse phase. The size of the particles was not more than 50 microns. The dispensing device was used for the powder injection. The technique of velocity measurement in high-temperature heterogeneous flow from the registration of flow by the high-speed camera is presented. The results of measurements indicate that the speed of the particles much lower than the speed of the gas. The results of measuring the heat flux along the axis of the plasma torch are presented. The heat flux was measured by means of regular mode uncooled sensors with tablet type calorimeters.

  4. Bottles of life: where plastic bottles battle bacteria | Wamanji ...

    African Journals Online (AJOL)

    Bottles of life: where plastic bottles battle bacteria. Eric Wamanji. Abstract. No Abstract. Discovery and Innovation Vol. 18(2) 2006: 80-82. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/dai.v18i2.15708 · AJOL African Journals Online. HOW TO ...

  5. Minimally-Invasive Gene Transfection by Chemical and Physical Interaction of Atmospheric Pressure Plasma Flow

    Science.gov (United States)

    Kaneko, Toshiro

    2014-10-01

    Non-equilibrium atmospheric pressure plasma irradiated to the living-cell is investigated for medical applications such as gene transfection, which is expected to play an important role in molecular biology, gene therapy, and creation of induced pluripotent stem (iPS) cells. However, the conventional gene transfection using the plasma has some problems that the cell viability is low and the genes cannot be transferred into some specific lipid cells, which is attributed to the unknown mechanism of the gene transfection using the plasma. Therefore, the time-controlled atmospheric pressure plasma flow is generated and irradiated to the living-cell suspended solution for clarifying the transfection mechanism toward developing highly-efficient and minimally- invasive gene transfection system. In this experiment, fluorescent dye YOYO-1 is used as the simulated gene and LIVE/DEAD Stain is simultaneously used for cell viability assay. By the fluorescence image, the transfection efficiency is calculated as the ratio of the number of transferred and surviving cells to total cell count. It is clarified that the transfection efficiency is significantly increased by the short-time (90%). This result indicates that the physical effects such as the electric field caused by the charged particles arriving at the surface of the cell membrane, and chemical effects associated with plasma-activated products in solution act synergistically to enhance the cell-membrane transport with low-damage. This work was supported by JSPS KAKENHI Grant Number 24108004.

  6. Sheared magnetospheric plasma flows and discrete auroral arcs: a quasi-static coupling model

    Directory of Open Access Journals (Sweden)

    M. M. Echim

    2007-02-01

    Full Text Available We consider sheared flows in magnetospheric boundary layers of tangential discontinuity type, forming a structure that is embedded in a large-scale convergent perpendicular electric field. We construct a kinetic model that couples the magnetospheric structure with the topside ionosphere. The contribution of magnetospheric electrons and ionospheric electrons and ions is taken into account into the current-voltage relationship derived for an electric potential monotonically decreasing with the altitude. The solution of the current continuity equation gives the distribution of the ionospheric potential consistent with the given magnetospheric electric potential. The model shows that a sheared magnetospheric flow generates current sheets corresponding to upward field-aligned currents, field-aligned potential drops and narrow bands of precipitating energy, as in discrete auroral arcs. Higher velocity magnetospheric sheared flows have the tendency to produce brighter and slightly broader arcs. An increase in arc luminosity is also associated with enhancements of magnetospheric plasma density, in which case the structures are narrower. Finally, the model predicts that an increase of the electron temperature of the magnetospheric flowing plasma corresponds to slightly wider arcs but does not modify their luminosity.

  7. Screening Effect of Plasma Flow on RMP Penetration in EXTRAP T2R

    Science.gov (United States)

    Frassinetti, Lorenzo; Olofsson, Erik; Brunsell, Per; Menmuir, Sheena; Drake, James

    2011-10-01

    The penetration of resonant magnetic perturbations (RMP) can be screened by plasma flow and the understanding of this phenomenon is important for ELM mitigation techniques. This work studies the screening effect in EXTRAP T2R. EXTRAP T2R is equipped with a feedback system able to suppress all error fields and to produce one or more external perturbations in a controlled fashion. The EXTRAP T2R feedback system is used to generate a RMP that interacts with the dynamics of its corresponding tearing mode (TM). The level of RMP penetration is quantified by analyzing the RMP effect on the TM amplitude and velocity. To study the screening effect, the flow is changed by applying a second perturbation that is non resonant (non-RMP). This produces the flow reduction without perturbing significantly the other parameters. By modifying the amplitude of the non-RMP, an experimental study of the flow effect on the RMP penetration is performed. Experimental results are compared with the model described in [Fitzpatrick R et al., Phys. Plasmas 8, 4489 (2001)].

  8. High-order Two-Fluid Plasma Solver for Direct Numerical Simulations of Magnetic Flows with Realistic Transport Phenomena

    Science.gov (United States)

    Li, Zhaorui; Livescu, Daniel

    2017-11-01

    The two-fluid plasma equations with full transport terms, including temperature and magnetic field dependent ion and electron viscous stresses and heat fluxes, frictional drag force, and ohmic heating term have been solved by using the sixth-order non-dissipative compact scheme for plasma flows in several different regimes. In order to be able to fully resolve all the dynamically relevant time and length scales while maintaining computational feasibility, the assumptions of infinite speed of light and negligible electron inertia have been made. The accuracy and robustness of this two-fluid plasma solver in handling plasma flows have been tested against a series of canonical problems, such as Alfven-Whistler dispersion relation, electromagnetic plasma shock, magnetic reconnection, etc. For all test cases, grid convergence tests have been conducted to achieve fully resolved results. The roles of heat flux, viscosity, resistivity, Hall and Biermann battery effects, are investigated for the canonical flows studied.

  9. 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.

  10. Plasma flow channels with ULF waves observed by Cluster and Double Star

    Directory of Open Access Journals (Sweden)

    M. Volwerk

    2005-11-01

    Full Text Available On 14 August 2004 a large-scale magnetic structure was observed by Double Star TC-1 in the southern lobe and by Cluster in the northern lobe of the magnetotail. The structure has the signature of a (localized dipolarization, decreasing Bx accompanied by an increasing Bz and a strong earthward flow. The propagation direction of this structure, however, seems to be more in the dawnward direction than earthward. The structure is accompanied by ULF waves with a period of ~5 min, which are simultaneously observed by the ground magnetometer station DIK, at the magnetic footpoints of the spacecraft. We interprete these waves as modes driven by the plasma flow and propagating in the flow channel.

  11. Plasma flow channels with ULF waves observed by Cluster and Double Star

    Directory of Open Access Journals (Sweden)

    M. Volwerk

    2005-11-01

    Full Text Available On 14 August 2004 a large-scale magnetic structure was observed by Double Star TC-1 in the southern lobe and by Cluster in the northern lobe of the magnetotail. The structure has the signature of a (localized dipolarization, decreasing Bx accompanied by an increasing Bz and a strong earthward flow. The propagation direction of this structure, however, seems to be more in the dawnward direction than earthward. The structure is accompanied by ULF waves with a period of ~5 min, which are simultaneously observed by the ground magnetometer station DIK, at the magnetic footpoints of the spacecraft. We interprete these waves as modes driven by the plasma flow and propagating in the flow channel.

  12. Plasma Sensor for High Bandwidth Mass-Flow Measurements at High Mach Numbers with RF Link Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposal is aimed at the development of a miniature high bandwidth (1 MHz class) plasma sensor for flow measurements at high enthalpies. This device uses a...

  13. Bursty bulk flows in the inner central plasma sheet: An effective means of earthward transport in the magnetotail

    Science.gov (United States)

    Angelopoulos, Vassilis; Kennel, Charles F.; Coroniti, F. V.; Pellat, R.; Kivelson, M. G.; Walker, R. J.; Baumjohann, W.; Paschmann, G.; Luhr, H.

    1992-01-01

    High speed flows in the Earth's Inner Central Plasma Sheet (ICPS) occur during enhanced flow intervals that have been termed Bursty Bulk Flow (BBF) events. The importance of different flow magnitude samples for Earthward transport in the ICPS are statistically evaluated and several representative BBF's and their relevance to Earthward transport are discussed. The selection of BBF's is automated in a database and they are shown to be responsible for most of the Earthward transport that occurs within the ICPS. The BBF related transport is compared to the transport measured within the entire plasma sheet during the 1985 AMPTE/IRM crossings of the magnetotail. The results show that BBF's last only a small fraction of the time in the plasma sheet but can account for several tens of percent of the Earthward particle and energy transfer and possibly all of the Earthward magnetic flux transfer in the plasma sheet.

  14. Localized fast flow disturbance observed in the plasma sheet and in the ionosphere

    Directory of Open Access Journals (Sweden)

    R. Nakamura

    2005-02-01

    Full Text Available An isolated plasma sheet flow burst took place at 22:02 UT, 1 September 2002, when the Cluster footpoint was located within the area covered by the Magnetometers-Ionospheric Radars-All-sky Cameras Large Experiment (MIRACLE. The event was associated with a clear but weak ionospheric disturbance and took place during a steady southward IMF interval, about 1h preceding a major substorm onset. Multipoint observations, both in space and from the ground, allow us to discuss the temporal and spatial scale of the disturbance both in the magnetosphere and ionosphere. Based on measurements from four Cluster spacecraft it is inferred that Cluster observed the dusk side part of a localized flow channel in the plasma sheet with a flow shear at the front, suggesting a field-aligned current out from the ionosphere. In the ionosphere the equivalent current pattern and possible field-aligned current location show a pattern similar to the auroral streamers previously obtained during an active period, except for its spatial scale and amplitude. It is inferred that the footpoint of Cluster was located in the region of an upward field-aligned current, consistent with the magnetospheric observations. The entire disturbance in the ionosphere lasted about 10min, consistent with the time scale of the current sheet disturbance in the magnetosphere. The plasma sheet bulk flow, on the other hand, had a time scale of about 2min, corresponding to the time scale of an equatorward excursion of the enhanced electrojet. These observations confirm that localized enhanced convection in the magnetosphere and associated changes in the current sheet structure produce a signature with consistent temporal and spatial scale at the conjugate ionosphere.

  15. Investigating the flow dynamics and chemistry of an expanding thermal plasma through CH(A-X) emission spectra

    NARCIS (Netherlands)

    Hansen, T. A. R.; Colsters, P. G. J.; M. C. M. van de Sanden,; Engeln, R.

    2011-01-01

    The gas flow in a linear plasma reactor and the plasma chemistry during hydrogenated amorphous carbon and graphite etching are investigated via time and spatially resolved measurements of the ion density and CH emission. A convolution of the ion and hydrocarbon density shows the importance of charge

  16. New construction of the magnetohydrodynamic spectrum of stationary plasma flows. II. Rayleigh-Taylor and Kelvin-Helmholtz instability

    NARCIS (Netherlands)

    Goedbloed, J. P.

    2009-01-01

    In a preceding paper [J. P. Goedbloed, Phys. Plasmas 16, 122110 (2009)] a new method was developed to compute the magnetohydrodynamic spectrum of waves and instabilities of stationary plasma flows by means of the construction of the solution paths, P-s and P-u, of stable waves and instabilities in

  17. Plasma flows, Birkeland currents and auroral forms in relation to the Svalgaard-Mansurov effect

    Directory of Open Access Journals (Sweden)

    P. E. Sandholt

    2012-05-01

    Full Text Available The traditional explanation of the polar cap magnetic deflections, referred to as the Svalgaard-Mansurov effect, is in terms of currents associated with ionospheric flow resulting from the release of magnetic tension on newly open magnetic field lines. In this study, we aim at an updated description of the sources of the Svalgaard-Mansurov effect based on recent observations of configurations of plasma flow channels, Birkeland current systems and aurorae in the magnetosphere-ionosphere system. Central to our description is the distinction between two different flow channels (FC 1 and FC 2 corresponding to two consecutive stages in the evolution of open field lines in Dungey cell convection, with FC 1 on newly open, and FC 2 on old open, field lines. Flow channel FC 1 is the result of ionospheric Pedersen current closure of Birkeland currents flowing along newly open field lines. During intervals of nonzero interplanetary magnetic field By component FC 1 is observed on either side of noon and it is accompanied by poleward moving auroral forms (PMAFs/prenoon and PMAFs/postnoon. In such cases the next convection stage, in the form of flow channel FC 2 on the periphery of the polar cap, is particularly important for establishing an IMF By-related convection asymmetry along the dawn-dusk meridian, which is a central element causing the Svalgaard-Mansurov effect. FC 2 flows are excited by the ionospheric Pedersen current closure of the northernmost pair of Birkeland currents in the four-sheet current system, which is coupled to the tail magnetopause and flank low-latitude boundary layer. This study is based on a review of recent statistical and event studies of central parameters relating to the magnetosphere-ionosphere current systems mentioned above. Temporal-spatial structure in the current systems is obtained by ground-satellite conjunction studies. On this point we emphasize the important information derived from the continuous ground monitoring

  18. Particle-in-Cell Modeling of Magnetized Argon Plasma Flow Through Small Mechanical Apertures

    Energy Technology Data Exchange (ETDEWEB)

    Adam B. Sefkow and Samuel A. Cohen

    2009-04-09

    Motivated by observations of supersonic argon-ion flow generated by linear helicon-heated plasma devices, a three-dimensional particle-in-cell (PIC) code is used to study whether stationary electrostatic layers form near mechanical apertures intersecting the flow of magnetized plasma. By self-consistently evaluating the temporal evolution of the plasma in the vicinity of the aperture, the PIC simulations characterize the roles of the imposed aperture and applied magnetic field on ion acceleration. The PIC model includes ionization of a background neutral-argon population by thermal and superthermal electrons, the latter found upstream of the aperture. Near the aperture, a transition from a collisional to a collisionless regime occurs. Perturbations of density and potential, with mm wavelengths and consistent with ion acoustic waves, propagate axially. An ion acceleration region of length ~ 200-300 λD,e forms at the location of the aperture and is found to be an electrostatic double layer, with axially-separated regions of net positive and negative charge. Reducing the aperture diameter or increasing its length increases the double layer strength.

  19. The Challenge of Incorporating Charged Dust in the Physics of Flowing Plasma Interactions

    Science.gov (United States)

    Jia, Y.; Russell, C. T.; Ma, Y.; Lai, H.; Jian, L.; Toth, G.

    2013-12-01

    The presence of two oppositely charged species with very different mass ratios leads to interesting physical processes and difficult numerical simulations. The reconnection problem is a classic example of this principle with a proton-electron mass ratio of 1836, but it is not the only example. Increasingly we are discovering situations in which heavy, electrically charged dust particles are major players in a plasma interaction. The mass of a 1mm dust particle is about 2000 proton masses and of a 10 mm dust particle about 2 million proton masses. One example comes from planetary magnetospheres. Charged dust pervades Enceladus' southern plume. The saturnian magnetospheric plasma flows through this dusty plume interacting with the charged dust and ionized plume gas. Multiple wakes are seen downstream. The flow is diverted in one direction. The field aligned-current systems are elsewhere. How can these two wake features be understood? Next we have an example from the solar wind. When asteroids collide in a disruptive collision, the solar wind strips the nano-scale charged dust from the debris forming a dusty plasma cloud that may be over 106km in extent and containing over 100 million kg of dust accelerated to the solar wind speed. How does this occur, especially as rapidly as it appears to happen? In this paper we illustrate a start on understanding these phenomena using multifluid MHD simulations but these simulations are only part of the answer to this complex problem that needs attention from a broader range of the community.

  20. Control of stationary crossflow modes in swept Hiemenz flows with dielectric barrier discharge plasma actuators

    Science.gov (United States)

    Wang, Zhefu; Wang, Liang; Fu, Song

    2017-09-01

    Sensitivity analyses and non-linear parabolized stability equations are solved to provide a computational assessment of the potential use of a Dielectric Barrier Discharge (DBD) plasma actuator for a prolonging laminar region in swept Hiemenz flow. The derivative of the kinetic energy with respect to the body force is deduced, and its components in different directions are defined as sensitivity functions. The results of sensitivity analyses and non-linear parabolized stability equations both indicate that the introduction of a body force as the plasma actuator at the bottom of a crossflow vortex can mitigate instability to delay flow transition. In addition, the actuator is more effective when placed more upstream until the neutral point. In fact, if the actuator is sufficiently close to the neutral point, it is likely to act as a strong disturbance over-riding the natural disturbance and dominating transition. Different operating voltages of the DBD actuators are tested, resulting in an optimal practice for transition delay. The results demonstrate that plasma actuators offer great potential for transition control.

  1. Plasma flow reactor for steady state monitoring of physical and chemical processes at high temperatures

    Science.gov (United States)

    Koroglu, Batikan; Mehl, Marco; Armstrong, Michael R.; Crowhurst, Jonathan C.; Weisz, David G.; Zaug, Joseph M.; Dai, Zurong; Radousky, Harry B.; Chernov, Alex; Ramon, Erick; Stavrou, Elissaios; Knight, Kim; Fabris, Andrea L.; Cappelli, Mark A.; Rose, Timothy P.

    2017-09-01

    We present the development of a steady state plasma flow reactor to investigate gas phase physical and chemical processes that occur at high temperature (1000 < T < 5000 K) and atmospheric pressure. The reactor consists of a glass tube that is attached to an inductively coupled argon plasma generator via an adaptor (ring flow injector). We have modeled the system using computational fluid dynamics simulations that are bounded by measured temperatures. In situ line-of-sight optical emission and absorption spectroscopy have been used to determine the structures and concentrations of molecules formed during rapid cooling of reactants after they pass through the plasma. Emission spectroscopy also enables us to determine the temperatures at which these dynamic processes occur. A sample collection probe inserted from the open end of the reactor is used to collect condensed materials and analyze them ex situ using electron microscopy. The preliminary results of two separate investigations involving the condensation of metal oxides and chemical kinetics of high-temperature gas reactions are discussed.

  2. Midtail plasma flows and the relationship to near-Earth substorm activity: A case study

    Science.gov (United States)

    Lopez, R. E.; Goodrich, C. C.; Reeves, G. D.; Belian, R. D.; Taktakishvili, A.

    1994-12-01

    Recent simulations of magnetotail reconnection have pointed to a link between plasma flows, dipolarization, and the substorm current wedge. In particular, Hesse and Birn (1991) have proposed that earthward jetting of plasma from the reconnection region transports flux into the near-Earth region. At the inner edge of the plasma sheet this flux piles up, producing a dipolarization of the magnetic field. The vorticity produced by the east-west deflection of the flow at the inner edge of the plasma sheet gives rise to field-aligned currents that have region 1 polarity. Thus in this scenario the earthward flow from the reconnection region produces the dipolarization and the current wedge in a self-consistent fashion. In this study we examine observations made on April 8, 1985 by the Active Magnetospheric Particle Tracer Explorers/Ion Release Module (IRM), the geosynchronous satellites 1979-053, 1983-019, and 1984-037, and Syowa station, as well as AE. This event is unique because IRM was located near the neutral sheet in the midnight sector for an extended period of time. Ground data show that there was ongoing activity in the IRM local time sector for several hours, beginning at 1800 UT and reaching a crescendo at 2300 UT. This activity was also accompanied by energetic particle variations, including injections, at geosynchronous orbit in the nighttime sector. Significantly, there were no fast flows at the neutral sheet until the great intensification of activity at 2300 UT. At that time, IRM recorded fast earthward flow simultaneous with a dipolarization of the magnetic field. We conclude that while the aforementioned scenario for the creation of the current wedge encounters serious problems explaining the earlier activity, the observations at 2300 UT are consistent with the scenario of Hesse and Birn (1991). On that basis it is argued that the physics of substorms is not exclusively rooted in the development of a global tearing mode. Processes at the inner edge of

  3. A new concept of high flow rate non-thermal plasma reactor for air treatment

    Energy Technology Data Exchange (ETDEWEB)

    Goujard, V.; Tatibouet, J.M. [Univ. de Poitiers, Poitiers (France). Centre national de la recherche scientifique, Laboratoire de Catalyse en Chimie Organique

    2010-07-01

    Although several non-thermal plasma reactors have been tested for air treatment at the laboratory scale, up-scaling to pilot or industrial scale remains a challenge because several parameters must be considered, such as hydrodynamic behaviour, maximum voltage in an industrial environment, and maintenance of the system. This paper presented a newly developed reactor which consists to a DBD plasma generated on individual supports that could be directly inserted in gas pipes where air flow must be treated. Elimination of 40 percent of 15 ppm of propene was obtained with a energy density as low as 10 J/L. The propene conversion increased when a manganese oxide based catalyst was used because the ozone produced by the plasma was used as an as an oxidant. A simple model of the plasma-catalyst reactor behaviour showed that more than 90 percent of propene conversion can be expected for an input energy density of 10 J/L and residual ozone concentration less than 100 ppb.

  4. Velocity statistics in holographic fluids: magnetized quark-gluon plasma and superfluid flow

    Energy Technology Data Exchange (ETDEWEB)

    Areán, Daniel [Max-Planck-Institut für Physik (Werner-Heisenberg-Institut),Föhringer Ring 6, D-80805, Munich (Germany); Zayas, Leopoldo A. Pando [The Abdus Salam International Centre for Theoretical Physics,Strada Costiera 11, 34014 Trieste (Italy); Michigan Center for Theoretical Physics, Department of Physics, University of Michigan,450 Church Street, Ann Arbor, MI 48109 (United States); Patiño, Leonardo; Villasante, Mario [Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México,A.P. 70-542, México D.F. 04510 (Mexico)

    2016-10-28

    We study the velocity statistics distribution of an external heavy particle in holographic fluids. We argue that when the dual supergravity background has a finite temperature horizon the velocity statistics goes generically as 1/v, compatible with the jet-quenching intuition from the quark-gluon plasma. A careful analysis of the behavior of the classical string whose apparent world sheet horizon deviates from the background horizon reveals that other regimes are possible. We numerically discuss two cases: the magnetized quark-gluon plasma and a model of superfluid flow. We explore a range of parameters in these top-down supergravity solutions including, respectively, the magnetic field and the superfluid velocity. We determine that the velocity statistics goes largely as 1/v, however, as we leave the non-relativistic regime we observe some deviations.

  5. Continuous Transitions between Discontinuous Magnetohydrodynamic Flows of Plasma and Its Heating

    CERN Document Server

    Ledentsov, L S

    2013-01-01

    The possibility that the type of discontinuous flow changes as the conditions gradually (continuously) change is investigated in connection with the problems arising when the results of numerical simulations of magnetic reconnection in plasma are interpreted. The conservation laws at a discontinuity surface in magnetohydrodynamics admit such transitions, but the socalled transition solutions for the boundary conditions that simultaneously satisfy two types of discontinuities should exist in this case. The specific form of such solutions has been found, and a generalized scheme of permitted transitions has been constructed on their basis. An expression for the jump in internal energy at discontinuity is derived. The dependence of the plasma heating efficiency on the type of discontinuity is considered.

  6. Measurement of the aerothermodynamic state in a high enthalpy plasma wind-tunnel flow

    Science.gov (United States)

    Hermann, Tobias; Löhle, Stefan; Zander, Fabian; Fasoulas, Stefanos

    2017-11-01

    This paper presents spatially resolved measurements of absolute particle densities of N2, N2+, N, O, N+ , O+ , e- and excitation temperatures of electronic, rotational and vibrational modes of an air plasma free stream. All results are based on optical emission spectroscopy data. The measured parameters are combined to determine the local mass-specific enthalpy of the free stream. The analysis of the radiative transport, relative and absolute intensities, and spectral shape is used to determine various thermochemical parameters. The model uncertainty of each analysis method is assessed. The plasma flow is shown to be close to equilibrium. The strongest deviations from equilibrium occur for N, N+ and N2+ number densities in the free stream. Additional measurements of the local mass-specific enthalpy are conducted using a mass injection probe as well as a heat flux and total pressure probe. The agreement between all methods of enthalpy determination is good.

  7. Measurements of the asymmetric dynamic sheath around a pulse biased sphere immersed in flowing metal plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wu Hongchen [Physics Department, Dalian University of Technology, Dalian 116024 (China); Anders, Andre [Lawrence Berkeley National Laboratory, University of California, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2008-08-01

    A long-probe technique was utilized to record the expansion and retreat of the dynamic sheath around a spherical substrate immersed in pulsed cathode arc metal plasma. Positively biased, long cylindrical probes were placed on the side and downstream of a negatively pulsed biased stainless steel sphere of 1 in. (25.4 mm) diameter. The amplitude and width of the negative high voltage pulses (HVPs) were 2 kV, 5 kV, 10 kV, and 2 {mu}s, 4 {mu}s, 10 {mu}s, respectively. The variation of the probe (electron) current during the HVP is a direct measure for the sheath expansion and retreat. Maximum sheath sizes were determined for the different parameters of the HVP. The expected rarefaction zone behind the biased sphere (wake) due to the fast plasma flow was clearly established and quantified.

  8. Control of dispersed-phase temperature in plasma flows by the spectral-brightness pyrometry method

    Science.gov (United States)

    Dolmatov, A. V.; Gulyaev, I. P.; Gulyaev, P. Yu; Iordan, V. I.

    2016-02-01

    In the present work, we propose a new method for measuring the distribution of temperature in the ensembles of condensed-phase particles in plasma spray flows. Interrelation between the spectral temperature of the particles and the distribution of camera brightness signal is revealed. The established inter-relation enables an in-situ calibration of measuring instruments using the objects under study. The spectral-brightness pyrometry method was approbated on a Plazer plasma-arc wire spraying facility at the Paton Institute of Electrical Welding (Ukrainian Academy of Sciences, Kiev) and on the Thermoplasma 50-1 powder spraying facility at the Institute of Theoretical and Applied Mechanics (Russian Academy of Sciences, Siberian Branch, Novosibirsk). The work was supported by the Russian Foundation for Basic Research (Grants Nos. 14-08-90428 and 15-48-00100).

  9. Measurements of the asymmetric, dynamic sheath around a pulse biased sphere immersed in flowing metal plasma

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre; Wu, Hongchen; Anders, Andre

    2008-06-13

    A long-probe technique was utilized to record the expansion and retreat of the dynamic sheath around a spherical substrate immersed in pulsed cathode arc metal plasma. Positively biased, long cylindrical probes were placed on the side and downstream of a negatively pulsed biased stainless steel sphere of 1" (25.4 mm) diameter. The amplitude and width of the negative high voltage pulses (HVP) were 2 kV, 5 kV, 10 kV, and 2 mu s, 4 mu s, 10 mu s, respectively. The variation of the probe (electron) current during the HVP is a direct measure for the sheath expansion and retreat. Maximum sheath sizes were determined for the different parameters of the HVP. The expected rarefaction zone behind the biased sphere (wake) due to the fast plasma flow was clearly established and quantified.

  10. A novel plasma heater for auto-ignition studies of turbulent non-premixed flows

    Science.gov (United States)

    Eitel, Felix; Pareja, Jhon; Geyer, Dirk; Johchi, Ayane; Michel, Florian; Elsäßer, Wolfgang; Dreizler, Andreas

    2015-10-01

    In this paper, the development and characterization of a novel test rig for auto-ignition (AI) studies of a fuel jet propagating into a hot turbulent co-flow is reported. The test rig, based on microwave plasma heating, is capable of achieving co-flow temperatures up to 1300 K and velocities up to 40 {ms}^{-1}. Important boundary conditions at nozzle exit such as temperature, species, and velocity field were determined to prove the capabilities and limitations of the test rig. Liftoff height (LOH) measurements of {CH}_4, {C}_2{H}_4, and {CH}4/{H}2 jets, propagating into a turbulent heated air co-flow, were taken using chemiluminescence imaging. Effects of the temperature and Reynolds number ( Re) of co-flow and jet were also studied. Results showed that the flame stabilization mechanism is supported substantially by AI rather than pure flame propagation. While the co-flow temperature dominates the AI process, the Re and temperature of the jet just have a small impact on the LOH.

  11. 27 CFR 4.26 - Estate bottled.

    Science.gov (United States)

    2010-04-01

    ... process (the wine at no time having left the premises of the bottling winery). (b) Special rule for... OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Standards of Identity for Wine § 4.26 Estate bottled. (a) Conditions for use. The term Estate bottled may be used by a bottling winery on a wine label...

  12. Relationships between circulating plasma concentrations and duodenal flows of essential amino acids in lactating dairy cows.

    Science.gov (United States)

    Patton, R A; Hristov, A N; Parys, C; Lapierre, H

    2015-07-01

    The objective of this study was to better define essential AA (EAA) requirements in lactating dairy cows through examination of the relationship between plasma essential AA concentration (p[EAA]) and predicted duodenal flow of essential AA (EAAduo). Our hypothesis was that at a given level of milk protein output, p[EAA] would remain steady in response to increasing EAAduo until the EAA requirement was met, at which point p[EAA] would increase rapidly in response to greater duodenal flow of EAA until p[EAA] reached a plateau as other body processes degraded excess EAA to avoid toxicity. Thus, the requirement of each EAA would be fulfilled when p[EAA] increased rapidly. To investigate this hypothesis, we compiled a literature database that included 102 studies with 420 treatment means that reported p[EAA], dietary nutrient content, body weight, and milk production. A second database was produced to validate relationships developed in the first database and included 32 studies with 98 treatment means. All relationships were evaluated as regression equations with study as a random factor. Breed, days in milk, body weight, and milk protein production had no effect on the plasma concentration of any EAA. Other than metabolizable protein supply, nutritional content of the rations did not affect p[EAA]. Only p[Arg] was affected by parity, with primiparous cows having higher concentrations of Arg than older cows. No break points in the relationship between p[EAA] versus EAAduo were detected as either steep increases or plateaus. Plasma Arg, Ile, Lys, Thr, and Val concentrations were best associated with their respective EAAduo as quadratic equations, whereas His, Leu, Met, and Phe were associated only linearly. Adding a quadratic term improved the adjusted R(2) or decreased the root mean square error marginally (affecting others. We conclude that over a wide range of protein intakes in lactating cows, plasma levels of EAA increase linearly with duodenal flow. No evidence

  13. Width and rugosity of the topological plasma flow structures and their relation to the radial flights of particle tracers

    Science.gov (United States)

    García, L.; Llerena Rodríguez, I.; Carreras, B. A.

    2015-09-01

    An analysis of the distributions of the width and rugosity of topological plasma flow structures is presented for some resistive pressure-gradient-driven turbulence results. The distributions of the radial excursions of particle tracers during trappings are compared with those of the width and rugosity of the flow structures.

  14. Blob/hole formation and zonal-flow generation in the edge plasma of the JET tokamak

    DEFF Research Database (Denmark)

    Xu, G.S.; Naulin, Volker; Fundamenski, W.

    2009-01-01

    The first experimental evidence showing the connection between blob/hole formation and zonal-flow generation was obtained in the edge plasma of the JET tokamak. Holes as well as blobs are observed to be born in the edge shear layer, where zonal-flows shear off meso-scale coherent structures, lead...

  15. Collisional Rayleigh-Taylor instability and shear-flow in equatorial Spread-F plasma

    Directory of Open Access Journals (Sweden)

    N. Chakrabarti

    2003-05-01

    Full Text Available Collisional Rayleigh-Taylor (RT instability is considered in the bottom side of the equatorial F-region. By a novel nonmodal calculation it is shown that for an applied shear flow in equilibrium, the growth of the instability is considerably reduced. Finite but small amounts of diffusion enhances the stabilization process. The results may be relevant to the observations of long-lived irregularities at the bottom-side of the F-layer.Key words. Ionosphere (ionospheric irregularities, equatorial ionosphere, plasma waves and instabilities

  16. Collisional Rayleigh-Taylor instability and shear-flow in equatorial Spread-F plasma

    Directory of Open Access Journals (Sweden)

    N. Chakrabarti

    Full Text Available Collisional Rayleigh-Taylor (RT instability is considered in the bottom side of the equatorial F-region. By a novel nonmodal calculation it is shown that for an applied shear flow in equilibrium, the growth of the instability is considerably reduced. Finite but small amounts of diffusion enhances the stabilization process. The results may be relevant to the observations of long-lived irregularities at the bottom-side of the F-layer.

    Key words. Ionosphere (ionospheric irregularities, equatorial ionosphere, plasma waves and instabilities

  17. Steam Plasma Flows Generated in Gerdien Arc: Environment for Energy Gas Production from Organics and for Surface Coatings

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    2011-01-01

    Roč. 6, č. 5 (2011), s. 792-801 ISSN 1880-5558. [Seventh International Conference on Flow Dynamics. Sendai, 01.11.2010-03.11.2010] R&D Projects: GA ČR GAP205/11/2070 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thermal Plasma * Dc Arc Plasma Torch * Gerdien Arc * Plasma Gasification Subject RIV: BL - Plasma and Gas Discharge Physics http://www.jstage.jst.go.jp/article/jfst/6/5/792/_pdf

  18. Active control of massively separated high-speed/base flows with electric arc plasma actuators

    Science.gov (United States)

    DeBlauw, Bradley G.

    The current project was undertaken to evaluate the effects of electric arc plasma actuators on high-speed separated flows. Two underlying goals motivated these experiments. The first goal was to provide a flow control technique that will result in enhanced flight performance for supersonic vehicles by altering the near-wake characteristics. The second goal was to gain a broader and more sophisticated understanding of these complex, supersonic, massively-separated, compressible, and turbulent flow fields. The attainment of the proposed objectives was facilitated through energy deposition from multiple electric-arc plasma discharges near the base corner separation point. The control authority of electric arc plasma actuators on a supersonic axisymmetric base flow was evaluated for several actuator geometries, frequencies, forcing modes, duty cycles/on-times, and currents. Initially, an electric arc plasma actuator power supply and control system were constructed to generate the arcs. Experiments were performed to evaluate the operational characteristics, electromagnetic emission, and fluidic effect of the actuators in quiescent ambient air. The maximum velocity induced by the arc when formed in a 5 mm x 1.6 mm x 2 mm deep cavity was about 40 m/s. During breakdown, the electromagnetic emission exhibited a rise and fall in intensity over a period of about 340 ns. After breakdown, the emission stabilized to a near-constant distribution. It was also observed that the plasma formed into two different modes: "high-voltage" and "low-voltage". It is believed that the plasma may be switching between an arc discharge and a glow discharge for these different modes. The two types of plasma do not appear to cause substantial differences on the induced fluidic effects of the actuator. In general, the characterization study provided a greater fundamental understanding of the operation of the actuators, as well as data for computational model comparison. Preliminary investigations

  19. Flow Cytometry Assessment of In Vitro Generated CD138+ Human Plasma Cells

    Directory of Open Access Journals (Sweden)

    Rayelle Itoua Maïga

    2014-01-01

    Full Text Available The in vitro CD40-CD154 interaction promotes human B lymphocytes differentiation into plasma cells. Currently, CD138 is the hallmark marker enabling the detection of human plasma cells, both in vitro and in vivo; its presence can be monitored by flow cytometry using a specific antibody. We have developed a culture system allowing for the differentiation of memory B lymphocytes. In order to detect the newly formed plasma cells, we have compared their staining using five anti-CD138 monoclonal antibodies (mAbs. As a reference, we also tested human cell lines, peripheral blood mononuclear cells, and bone marrow samples. The five anti-CD138 mAbs stained RPMI-8226 cells (>98% with variable stain index (SI. The highest SI was obtained with B-A38 mAb while the lowest SI was obtained with DL-101 and 1D4 mAbs. However, the anti-CD138 mAbs were not showing equivalent CD138+ cells frequencies within the generated plasma cells. B-A38, B-B4, and MI-15 were similar (15–25% while DL-101 mAb stained a higher proportion of CD138-positive cells (38–42%. DL-101 and B-A38 mAbs stained similar populations in bone marrow samples but differed in their capacity to bind to CD138high and CD138lo cell lines. In conclusion, such cellular fluctuations suggest heterogeneity in human plasma cell populations and/or in CD138 molecules.

  20. Ocular injuries from flying bottle caps.

    Science.gov (United States)

    Fonseka, C

    1993-12-01

    Three cases of serious eye injury are described from flying metal caps of carbonated drink bottles. The injuries occurred while attempting to open the bottle in an unconventional and dangerous way. Though injuries from flying bottle caps have been described before, they have occurred when the bottle exploded. This is the first report of eye injuries caused by bottle caps while opening and are similar to the injuries caused by champagne corks.

  1. Gas flow rate dependence of the discharge characteristics of a helium atmospheric pressure plasma jet interacting with a substrate

    Science.gov (United States)

    Yan, Wen; Economou, Demetre J.

    2017-10-01

    A 2D (axisymmetric) computational study of the discharge characteristics of an atmospheric pressure plasma jet as a function of gas flow rate was performed. The helium jet emerged from a dielectric tube, with an average gas flow velocity in the range 2.5-20 m s-1 (1 atm, 300 K) in a nitrogen ambient, and impinged on a substrate a short distance dowstream. The effect of the substrate conductivity (conductror versus insulator) was also studied. Whenever possible, simulation predictions were compared with published experimental observations. Discharge ignition and propagation in the dielectric tube were hardly affected by the He gas flow velocity. Most properties of the plasma jet, however, depended sensitively on the He gas flow velocity, which determined the concentration distributions of helium and nitrogen in the mixing layer forming in the gap between the tube exit and the substrate. At low gas flow velocity, the plasma jet evolved from a hollow (donut-shaped) feature to one where the maximum of electron density was on axis. When the gas flow velocity was high, the plasma jet maintained its hollow structure until it struck the substrate. For a conductive substrate, the radial ion fluxes to the surface were relatively uniform over a radius of ~0.4-0.8 mm, and the dominant ion flux was that of He+. For a dielectric substrate, the radial ion fluxes to the surface peaked on the symmetry axis at low He gas flow velocity, but a hollow ion flux distribution was observed at high gas flow velocity. At the same time, the main ion flux switched from N2+ to He2+ as the He gas flow velocity increased from a low to a high value. The diameter of the plasma ‘footprint’ on the substrate first increased with increasing He gas flow velocity, and eventually saturated with further increases in velocity.

  2. HF DBD plasma actuators for reduction of cylinder noise in flow

    Science.gov (United States)

    Kopiev, V. F.; Kazansky, P. N.; Kopiev, V. A.; Moralev, I. A.; Zaytsev, M. Yu

    2017-11-01

    Surface high frequency dielectric barrier discharge (HF DBD) was used to reduce flow-induced noise, radiated by circular cylinder in cross flow. Effect of HF DBD actuators is studied for flow velocity up to 80 m s‑1 (Reynolds numbers up to 2.18 · 105), corresponding to the typical aircraft landing approach speed. Noise measurements were performed by microphone array in anechoic chamber; averaged flow parameters were studied by particle image velocimetry (PIV). Actuator was powered by high-frequency voltage in hundreds kHz range in steady or modulated mode with the modulation frequency of 0.3–20 kHz (Strouhal number St of 0.4 to 20). It is demonstrated that upstream directed plasma actuators are able to reduce the vortex noise of a cylinder by 10 dB. Noise reduction is accompanied by significant reorganization of the wake behind a cylinder, decreasing both wake width and turbulence level. The physical mechanism related to broadband noise control by HF DBD actuator is also discussed.

  3. Effect of purging fluids for optical diagnostics on mainstream supersonic plasma flows

    Energy Technology Data Exchange (ETDEWEB)

    Bouchillon, C.W.; Norton, O.P.; Cook, R.L. [Mississippi State Univ., Mississippi State, MS (United States)

    1993-12-31

    A pneumatic air cannon has been used to provide optical access to high speed MHD plasma flows. When the optical access port is occluded by slag deposits, this pneumatic air cannon (known as the {open_quotes}slag blaster{close_quotes}) discharges a pulse of pressurized air through the port to clear the port of the obstructing slag. This device has been employed, at a reduced pressure level, in the aerodynamic duct at the Coal-Fired Flow Facility (CFFF), a DOE owned test facility operated by the University of Tennessee Space Institute (UTSI). A commercial computational fluid dynamics (CFD) package, PHOENICS, was used to calculate the effect of this pressurized discharge on the flow in the aerodynamic duct. The calculations reported here are fully transient, compressible, and three dimensional. For these calculations, a compressed gas tank with a volume of 0.125 cubic feet (0.0035 m{sup 3}), initially pressurized to 6 atmospheres, is assumed to discharge through a pipe 1 inch (25 mm) in diameter into the aerodynamic duct. The results of these calculations show that an oblique shock wave is formed in the aerodynamic duct as the supersonic flow in the duct is turned by the flow from the optical port. This shock impinges on the opposite wall of the aerodynamic duct, across from optical port where the pressurized discharge is introduced. The temperature gradient at wall increases at this point, indicating an increase in the convective heat flux. The maximum rate of discharge from the optical port is reached approximately 7 milliseconds after the opening of the valve, and the entire transient pulse lasts only 0.11 seconds. Furthermore, the added fluid does not cause choking of the flow in the aerodynamic duct, and no shock waves are observed to propagate upstream from the injection point.

  4. Flow induced dispersion analysis rapidly quantifies proteins in human plasma samples.

    Science.gov (United States)

    Poulsen, Nicklas N; Andersen, Nina Z; Østergaard, Jesper; Zhuang, Guisheng; Petersen, Nickolaj J; Jensen, Henrik

    2015-07-07

    Rapid and sensitive quantification of protein based biomarkers and drugs is a substantial challenge in diagnostics and biopharmaceutical drug development. Current technologies, such as ELISA, are characterized by being slow (hours), requiring relatively large amounts of sample and being subject to cumbersome and expensive assay development. In this work a new approach for quantification based on changes in diffusivity is presented. The apparent diffusivity of an indicator molecule interacting with the protein of interest is determined by Taylor Dispersion Analysis (TDA) in a hydrodynamic flow system. In the presence of the analyte the apparent diffusivity of the indicator changes due to complexation. This change in diffusivity is used to quantify the analyte. This approach, termed Flow Induced Dispersion Analysis (FIDA), is characterized by being fast (minutes), selective (quantification is possible in a blood plasma matrix), fully automated, and being subject to a simple assay development. FIDA is demonstrated for quantification of the protein Human Serum Albumin (HSA) in human plasma as well as for quantification of an antibody against HSA. The sensitivity of the FIDA assay depends on the indicator-analyte dissociation constant which in favourable cases is in the sub-nanomolar to picomolar range for antibody-antigen interactions.

  5. Effects of magnetic islands on resonant field penetration and toroidal torques at slow plasma flow

    Science.gov (United States)

    Li, L.; Liu, Y. Q.; Wang, N.; Zhong, F. C.; Luan, Q.; Wang, Y.

    2017-12-01

    The presence of a chain of magnetic islands, produced by externally applied tri-dimensional fields at a rational surface, is numerically found to have significant effects on the resonant response, as well as on the associated toroidal torques, in a toroidal tokamak plasma with conventional aspect ratio, strong shaping, and in the regime of slow toroidal flow. With an ad hoc assumption of the local flattening of the equilibrium pressure profile by the islands, it is found that the primary effect is the increasing of the resonant response by islands, at slow flow, due to the reduction of the favourable average curvature effect. This also leads to the reduction of the toroidal torques, in particular that associated with the neoclassical toroidal viscosity. Partial or complete flattening of the local pressure profile, depending on the island size, results in partial or full recovering of the so called constant-ψ plasma response regime. Computational results are well fitted by analytic models for the two extreme cases: the case of complete flattening and the case of no flattening of the local pressure.

  6. Thermochemical Nonequilibrium 2D Modeling of Nitrogen Inductively Coupled Plasma Flow

    Science.gov (United States)

    Yu, Minghao; Yusuke, Takahashi; Hisashi, Kihara; Ken-ichi, Abe; Kazuhiko, Yamada; Takashi, Abe; Satoshi, Miyatani

    2015-09-01

    Two-dimensional (2D) numerical simulations of thermochemical nonequilibrium inductively coupled plasma (ICP) flows inside a 10-kW inductively coupled plasma wind tunnel (ICPWT) were carried out with nitrogen as the working gas. Compressible axisymmetric Navier-Stokes (N-S) equations coupled with magnetic vector potential equations were solved. A four-temperature model including an improved electron-vibration relaxation time was used to model the internal energy exchange between electron and heavy particles. The third-order accuracy electron transport properties (3rd AETP) were applied to the simulations. A hybrid chemical kinetic model was adopted to model the chemical nonequilibrium process. The flow characteristics such as thermal nonequilibrium, inductive discharge, effects of Lorentz force were made clear through the present study. It was clarified that the thermal nonequilibrium model played an important role in properly predicting the temperature field. The prediction accuracy can be improved by applying the 3rd AETP to the simulation for this ICPWT. supported by Grant-in-Aid for Scientific Research (No. 23560954), sponsored by the Japan Society for the Promotion of Science

  7. Current flow instability and nonlinear structures in dissipative two-fluid plasmas

    Science.gov (United States)

    Koshkarov, O.; Smolyakov, A. I.; Romadanov, I. V.; Chapurin, O.; Umansky, M. V.; Raitses, Y.; Kaganovich, I. D.

    2018-01-01

    The current flow in two-fluid plasma is inherently unstable if plasma components (e.g., electrons and ions) are in different collisionality regimes. A typical example is a partially magnetized E ×B plasma discharge supported by the energy released from the dissipation of the current in the direction of the applied electric field (perpendicular to the magnetic field). Ions are not magnetized so they respond to the fluctuations of the electric field ballistically on the inertial time scale. In contrast, the electron current in the direction of the applied electric field is dissipatively supported either by classical collisions or anomalous processes. The instability occurs due to a positive feedback between the electron and ion current coupled by the quasi-neutrality condition. The theory of this instability is further developed taking into account the electron inertia, finite Larmor radius and nonlinear effects. It is shown that this instability results in highly nonlinear quasi-coherent structures resembling breathing mode oscillations in Hall thrusters.

  8. Accuracy of Bone Marrow Flow Cytometry Analysis in Patients With Plasma Cell Neoplasm in Thailand: A Single Institutional Study.

    Science.gov (United States)

    Limvorapitak, Wasithep; Srisum-Ang, Thammasiree; Chimres, Chutima; Warnnissorn, Naree; Kanitsap, Nonglak

    2016-03-01

    Plasma cell neoplasm is a common hematologic malignancy. Treatment with novel agents results in favorable outcomes. Reliable investigations are required to monitor the residual disease, especially after such effective treatments. Flow cytometric analysis is a speedy and accurate method to detect abnormal cells. The aim of this study was to determine diagnostic performance of flow cytometry in the detection of abnormal plasma cells in bone marrow specimens. We included bone marrow samples taken from patients suspected to harbor plasma cell neoplasm at the time of diagnosis or follow-up after treatment from 2013 to 2015. Flow cytometric analyses, using cluster of differentiation (CD)19/CD20/CD27/CD38/CD45/CD56/CD117/CD138 and cytoplasmic κ/λ, were done and results compared with morphologic evaluation of marrow aspirate smear, histology, and immunohistochemistry of marrow biopsy and protein electrophoretic analyses. A total of 154 specimens were included. Plasma cell neoplasm was detected in 56 samples (36.4%). Most abnormal plasma cells in this study were CD19-negative (CD19(-))/CD20(-)/CD27(+)/CD38(+)/CD45(-) (or weakly positive)/CD56(+)/CD117(+)/CD138(+). Light chain restriction was found only in 18 samples (32.1%). Sensitivity and specificity of flow cytometric analysis were 91.1% and 96.9%, respectively. For the follow-up cohort, sensitivity and specificity were 86.7% and 66.7%, respectively. Analysis of plasma cell neoplasm using flow cytometry has high sensitivity and specificity. As an adjunct to marrow histology and immunohistochemistry, flow cytometry can be used in diagnosis of plasma cell neoplasm and more importantly in monitoring the disease after treatment. We propose a limited panel of CD19/CD38/CD45/CD56/CD117/CD138 for detecting minimal residual disease in Thai patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Geodesic acoustic modes and zonal flows in rotating large-aspect-ratio tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ilgisonis, V I; Lakhin, V P; Smolyakov, A I; Sorokina, E A [Department of Physics and Engineering Physics, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation)

    2011-06-15

    The effect of equilibrium plasma rotation (toroidal and poloidal) on low-frequency, electrostatic modes-the geodesic acoustic modes (GAMs) and the zonal flows (ZFs)-in large aspect ratio tokamaks is studied within the framework of ideal MHD. It is shown that the plasma rotation results in a frequency up-shift of the ordinary GAM. The new branch of continuum modes induced by the poloidal rotation is found. This mode originates from the opposite sign Doppler shift of frequency due to poloidal rotation for m = {+-}1 poloidal side-band harmonics of the perturbed mass density, pressure and parallel velocity. In the case of slow poloidal rotation ({Omega}{sub P} << c{sub s}/qR{sub 0}) its frequency is close to the sound frequency c{sub s}/qR{sub 0} ({Omega}{sub P} is the poloidal angular velocity, c{sub s} is the speed of sound, q is the safety factor and R{sub 0} is the major radius of tokamak). The mode can be called the rotation-induced acoustic mode. This mode disappears in the case of purely toroidal plasma rotation. The frequency of the new mode in the case of relatively slow poloidal rotation ({Omega}{sub P} {<=} c{sub s}/qR{sub 0}) is lower than the frequency of the ordinary GAM modified by plasma rotation. In the case of larger poloidal angular velocities {Omega}{sub P} ({Omega}{sub P} {>=} 2c{sub s}/qR{sub 0}) the mode becomes unstable and is identified as the unstable ZF. With a further increase in the poloidal angular velocity at constant toroidal angular velocity the instability is suppressed, and the mode turns again into a marginally stable, oscillating mode.

  10. Influence of the magnetic field configuration on the plasma flow in Hall thrusters

    Science.gov (United States)

    Andreussi, T.; Giannetti, V.; Leporini, A.; Saravia, M. M.; Andrenucci, M.

    2018-01-01

    In Hall propulsion, the thrust is provided by the acceleration of ions in a plasma generated in a cross-field configuration. Standard thruster configurations have annular channels with an almost radial magnetic field at the channel exit. A potential difference is imposed in the axial direction and the intensity of the magnetic field is calibrated in order to hinder the electron motion, while leaving the ions non-magnetised. Magnetic field lines can be assumed, as a first approximation, as lines of constant electron temperature and of thermalized potential. In typical thruster configurations, the discharge occurs inside a ceramic channel and, due to plasma–wall interactions, the electron temperature is typically low, less than few tens of eV. Hence, the magnetic field lines can be effectively used to tailor the distribution of the electrostatic potential. However, the erosion of the ceramic walls caused by the ion bombardment represents the main limiting factor of the thruster lifetime and new thruster configurations are currently under development. For these configurations, classical first order models of the plasma dynamics fail to grasp the influence of the magnetic topology on the plasma flow. In the present paper, a novel approach to investigate the correlation between magnetic field topology and thruster performance is presented. Due to the anisotropy induced by the magnetic field, the gradients of the plasma properties are assumed to be mainly in the direction orthogonal to the local magnetic field, thus enabling a quasi-one-dimensional description in magnetic coordinates. Theoretical and experimental investigations performed on a 5 kW class Hall thruster with different magnetic field configurations are then presented and discussed.

  11. A flow cytometric method for characterization of circulating cell-derived microparticles in plasma

    Directory of Open Access Journals (Sweden)

    Morten Hjuler Nielsen

    2014-02-01

    Full Text Available Background and aim: Previous studies on circulating microparticles (MPs indicate that the majority of MPs are of a size below the detection limit of most standard flow cytometers. The objective of the present study was to establish a method to analyze MP subpopulations above the threshold of detection of a new generation BD FACSAria™ III digital flow cytometer. Methods: We analyzed MP subpopulations in plasma from 24 healthy individuals (9 males and 15 females. MPs were identified according to their size (<1.0-µm, by Lactadherin-FITC labelling, and by exposure of cell-specific markers. The sensitivity of the flow cytometer was tested against that of a previous-generation instrument FC500. Reproducibility of the FACSAria and our set-up was investigated, and the percentage of phosphatidylserine (PS exposing MPs binding Lactadherin was determined. Results: By using a flow cytometric approach we identified and quantitated MPs derived from platelets, monocytes, erythrocytes and endothelial cells. In addition, levels of tissue factor-positive MPs were determined. The FACSAria demonstrated improved sensitivity and increased MP detection range compared to the FC500 instrument. The reproducibility of PS+PMP and PS+MP measurements was 11.7 and 23.2%, respectively. When expressed as a percentage of total MPs, the PS-positive MP population represented 15.1±5.5%, and PS-positive MPs were significantly increased in men. Conclusion: We have established a method to measure MPs above the detection limit of a new generation flow cytometer and derived from a number of cell-types in a healthy population of men and women.

  12. Simultaneous evaluation of plasma membrane integrity, acrosomal integrity, and mitochondrial membrane potential in bovine spermatozoa by flow cytometry.

    Science.gov (United States)

    Kanno, Chihiro; Kang, Sung-Sik; Kitade, Yasuyuki; Yanagawa, Yojiro; Takahashi, Yoshiyuki; Nagano, Masashi

    2016-08-01

    The present study aimed to develop an objective evaluation procedure to estimate the plasma membrane integrity, acrosomal integrity, and mitochondrial membrane potential of bull spermatozoa simultaneously by flow cytometry. Firstly, we used frozen-thawed semen mixed with 0, 25, 50, 75 or 100% dead spermatozoa. Semen was stained using three staining solutions: SYBR-14, propidium iodide (PI), and phycoerythrin-conjugated peanut agglutinin (PE-PNA), for the evaluation of plasma membrane integrity and acrosomal integrity. Then, characteristics evaluated by flow cytometry and by fluorescence microscopy were compared. Characteristics of spermatozoa (viability and acrosomal integrity) evaluated by flow cytometry and by fluorescence microscopy were found to be similar. Secondly, we attempted to evaluate the plasma membrane integrity, acrosomal integrity, and also mitochondrial membrane potential of spermatozoa by flow cytometry using conventional staining with three dyes (SYBR-14, PI, and PE-PNA) combined with MitoTracker Deep Red (MTDR) staining (quadruple staining). The spermatozoon characteristics evaluated by flow cytometry using quadruple staining were then compared with those of staining using SYBR-14, PI, and PE-PNA and staining using SYBR-14 and MTDR. There were no significant differences in all characteristics (viability, acrosomal integrity, and mitochondrial membrane potential) evaluated by quadruple staining and the other procedures. In conclusion, quadruple staining using SYBR-14, PI, PE-PNA, and MTDR for flow cytometry can be used to evaluate the plasma membrane integrity, acrosomal integrity, and mitochondrial membrane potential of bovine spermatozoa simultaneously.

  13. The Study of Two-Ion Flow in The Plasma Presheath

    Science.gov (United States)

    Wang, Xu; Ko, Eunsuk; Hershkowitz, Noah

    2004-11-01

    The ion flow created in the presheath of a weakly ionized He-Ar plasma is studied experimentally. Mobility limited flow was used to predict ion drift velocities of each species and found to be in agreement with previous LIF measurements [1] for Ar ions 2.0cm from the boundary. The phase velocity of ion acoustic wave was measured by launching a continuous sinusoidal wave, detecting the wave from electron saturation current with a cylindrical probe and time sampling with a boxcar averager. The relationship between Ar^+ and He^+ drift velocities was established by the wave dispersion relation. He^+ drift velocities were determined for given Ar^+ drift velocities and compared to the mobility limited flow predictions. Ion-ion electrostatic two stream instabilities were observed in the presheath for different positions, partial and total pressures to determine if this instability alters ion drift velocities near the sheath-presheath boundary. The instabilities predicted by fluid and kinetic dispersion relations are compared to the data. [1] G. D. Severn, Xu Wang, Eunsuk Ko and N. Hershkowitz, Phys. Rev. Lett. 90, 145001 (2003).

  14. Experimental Study of the Power Profile Airfoil Equipped with Plasma Flow Control

    Science.gov (United States)

    Daniel, Libin; Jacob, Jamey

    2013-11-01

    This presentation discusses results from an experimental study of the power profile airfoil at low Reynolds number. The power profile airfoil was developed by AMO Smith and consists of a blunt trailing edge shape with two wall jets near the trailing edge. The replacement of streamlining with properly designed blowing is used to prevent flow separation and additionally offers potential applications as a powered high-lift system, propulsive system, or low inertia control device. The 2D wind-tunnel model consists of the 22.5% thick power profile airfoil equipped with a movable trailing edge plug to direct flow along the trailing edge streamline. Compressed air was passed into the model via a plenum with flow conditioning devices to create pressure backdrop to allow uniform blowing at the trailing edge. The effects of varying jet momentum coefficient and trailing edge positioning on the aerodynamic characteristics are observed with both wake surveys and PIV. The impact of plasma synthetic jet actuators (PSJA) placed along the trailing edge of the power profile airfoil is also discussed. PSJA operation is compared to the baseline power profile airfoil both alone and working with the blowing to provide additional control authority.

  15. Final Technical Report: Numerical and Experimental Investigation of Turbulent Transport Control via Shaping of Radial Plasma Flow Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Eugenio

    2014-05-02

    The strong coupling between the different physical variables involved in the plasma transport phenomenon and the high complexity of its dynamics call for a model-based, multivariable approach to profile control where those predictive models could be exploited. The overall objective of this project has been to extend the existing body of work by investigating numerically and experimentally active control of unstable fluctuations, including fully developed turbulence and the associated cross-field particle transport, via manipulation of flow profiles in a magnetized laboratory plasma device. Fluctuations and particle transport can be monitored by an array of electrostatic probes, and Ex B flow profiles can be controlled via a set of biased concentric ring electrodes that terminate the plasma column. The goals of the proposed research have been threefold: i- to develop a predictive code to simulate plasma transport in the linear HELCAT (HELicon-CAThode) plasma device at the University of New Mexico (UNM), where the experimental component of the proposed research has been carried out; ii- to establish the feasibility of using advanced model-based control algorithms to control cross-field turbulence-driven particle transport through appropriate manipulation of radial plasma flow profiles, iii- to investigate the fundamental nonlinear dynamics of turbulence and transport physics. Lehigh University (LU), including Prof. Eugenio Schuster and one full-time graduate student, has been primarily responsible for control-oriented modeling and model-based control design. Undergraduate students have also participated in this project through the National Science Foundation Research Experience for Undergraduate (REU) program. The main goal of the LU Plasma Control Group has been to study the feasibility of controlling turbulence-driven transport by shaping the radial poloidal flow profile (i.e., by controlling flow shear) via biased concentric ring electrodes.

  16. The Center for Momentum Transport and Flow Organization in Plasmas - Final Scientific Report

    Energy Technology Data Exchange (ETDEWEB)

    Munsat, Tobin [Univ. of Colorado, Boulder, CO (United States)

    2015-12-14

    fields, all of the instabilities co-exist, leading to rich plasma dynamics and fully developed broadband turbulence. Edge-Turbulence and Flow Experiments in NSTX: A series of Gas Puff Imaging (GPI) observations on NSTX revealed a quasi-periodic oscillation in the plasma edge preceding the L-H transition in a limited set of neutral beam heated plasmas. These ~3 kHz flow oscillations exhibit both long wavelength and long correlation lengths, suggesting they are zonal-flow-like. The flow oscillations are strongly correlated with modulations of the level of edge turbulence, thus the system appears to undergo a predator--prey-type limit-cycle preceding the L-H transition. However, a clear trigger for the L-H transition was not observed. Reynolds stress profiles were obtained directly from image velocimetry for L-mode periods ELM-Precursor Studies in NSTX: A separate study based on NSTX-GPI data captured the two-dimensional evolution of edge-localized mode (ELM) precursors. Precursor events were observed preceding ELMs and ELM-induced H–L back-transitions in radio-frequency heated H-mode plasmas, and the growth of the precursor mode through the ELM filamentation was imaged in the plane perpendicular to the local B-field. Strong edge intensity modulations appeared to propagate in the electron diamagnetic direction while steadily drifting radially outwards. Intensity fluctuations were observed at frequencies around 20 kHz and wavenumbers of 0.05-0.2 cm-1. Upon growing to a trigger point, precursor fluctuations were seen to form filamentary structures and move into the scrape-off layer (SOL) explosively with radial velocities peaking at 8 km/s. Once in the SOL, filaments reverse their propagation direction and travel in the ion diamagnetic direction. Edge intensity fluctuations were strongly correlated with magnetic signals from Mirnov coils, and toroidally distributed coils estimated toroidal mode numbers of n=5-10. Quantitatively similar precursors have been

  17. Comparison of the orientation of small-scale electron density irregularities and F region plasma flow direction

    Directory of Open Access Journals (Sweden)

    E. D. Tereshchenko

    2000-08-01

    Full Text Available Results are shown from an experimental campaign where satellite scintillation was observed at three sites at high latitudes and, simultaneously, the F region plasma flow was measured by the nearby EISCAT incoherent scatter radar. The anisotropy parameters of field-aligned irregularities are determined from amplitude scintillation using a method based on the variance of the relative logarithmic amplitude. The orientation of the anisotropy in a plane perpendicular to the geomagnetic field is compared with the direction of F region plasma flow. The results indicate that in most cases a good agreement between the two directions is obtained.Key words: Ionosphere (auroral ionosphere; ionospheric irregularities

  18. Comparison of the orientation of small-scale electron density irregularities and F region plasma flow direction

    Directory of Open Access Journals (Sweden)

    E. D. Tereshchenko

    Full Text Available Results are shown from an experimental campaign where satellite scintillation was observed at three sites at high latitudes and, simultaneously, the F region plasma flow was measured by the nearby EISCAT incoherent scatter radar. The anisotropy parameters of field-aligned irregularities are determined from amplitude scintillation using a method based on the variance of the relative logarithmic amplitude. The orientation of the anisotropy in a plane perpendicular to the geomagnetic field is compared with the direction of F region plasma flow. The results indicate that in most cases a good agreement between the two directions is obtained.

    Key words: Ionosphere (auroral ionosphere; ionospheric irregularities

  19. Supersonic flow with shock waves. Monte-Carlo calculations for low density plasma. I; Flujo supersonico de un plasma con ondas de choque, un metodo de montecarlo para plasmas de baja densidad, I.

    Energy Technology Data Exchange (ETDEWEB)

    Almenara, E.; Hidalgo, M.; Saviron, J. M.

    1980-07-01

    This Report gives preliminary information about a Monte Carlo procedure to simulate supersonic flow past a body of a low density plasma in the transition regime. A computer program has been written for a UNIVAC 1108 machine to account for a plasma composed by neutral molecules and positive and negative ions. Different and rather general body geometries can be analyzed. Special attention is played to tho detached shock waves growth In front of the body. (Author) 30 refs.

  20. Magnetohydrodynamic Simulation of the Chordal Wire-Array Plasma Flow Switch

    Science.gov (United States)

    Domonkos, Matthew; Amdahl, David

    2015-11-01

    The coaxial plasma flow switch (PFS) using a chordal wire array armature was first studied experimentally and computationally in the 1980's. That work revealed significant current interruption (dI/dt ~ 5 MA/ μs) as well as continuum x-ray emission representative of 30-45 keV bremsstrahlung. The work concluded that the voltage spike associated with the current interruption accelerated highly magnetized ions downstream at high velocity, and that energy exchange between the ions and electrons and their subsequent acceleration at the downstream boundary of the apparatus were responsible for the x-ray production. This work revisits the PFS operation up to and just beyond the point of armature lift-off from the coaxial section, where the magnetohydrodynamic model is valid and relevant. The early-time energy deposition in the wires from the pulse discharge is modeled in high-resolution 1-D and is used to set the initial conditions for the full-scale 3-D calculation. The wire array is assumed to have expanded from the initial r =0.01 cm uniformly and only in the axial direction, while the areal mass density retains its intended variation with radius. 3-D calculations are used to examine the armature, including magnetic field diffusion, as it is propelled along the coaxial geometry. These calculations will be used to set the initial conditions for follow-on particle or particle-fluid hybrid calculations of the propagation of ions and electrons to downstream obstacles and to calculate the x-ray production from the interactions of the flowing plasma with the obstacles.

  1. Polychromatic flow cytometry is more sensitive than microscopy in detecting small monoclonal plasma cell populations.

    Science.gov (United States)

    Tran, Daniel N; Smith, Sandy A B C; Brown, David A; Parker, Andrew J C; Joseph, Joanne E; Armstrong, Nicola; Sewell, William A

    2017-03-01

    There is an emerging role for flow cytometry (FC) in the assessment of small populations of plasma cells (PC). However, FC's utility has been questioned due to consistent underestimation of the percentage of PC compared to microscopy. A retrospective study was performed on bone marrow samples analysed by 8-colour FC. Plasma cell populations were classified as polyclonal or monoclonal based on FC analysis. FC findings were compared with microscopy of aspirates, histology and immunohistochemistry of trephine biopsies, and immunofixation (IFX) of serum and/or urine. FC underestimated PC compared to aspirate and trephine microscopy. The 10% diagnostic cutoff for MM on aspirate microscopy corresponded to a 3.5% cutoff on FC. Abnormal plasma cell morphology by aspirate microscopy and clonality by FC correlated in 229 of 294 cases (78%). However, in 50 cases, FC demonstrated a monoclonal population but microscopy reported no abnormality. In 15 cases, abnormalities were reported by microscopy but not by FC. Clonality assessment by trephine microscopy and FC agreed in 251/280 cases (90%), but all 29 discordant cases were monoclonal by FC and not monoclonal by microscopy. These cases had fewer PC and proportionally more polyclonal PC, and when IFX detected a paraprotein, it had the same light chain as in the PC determined by FC. FC was more sensitive in detecting monoclonal populations that were small or accompanied by polyclonal PC. This study supports the inclusion of FC in the evaluation of PC, especially in the assessment of small populations. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

  2. Magnetic field production via the Weibel instability in interpenetrating plasma flows

    Science.gov (United States)

    Huntington, C. M.; Manuel, M. J.-E.; Ross, J. S.; Wilks, S. C.; Fiuza, F.; Rinderknecht, H. G.; Park, H.-S.; Gregori, G.; Higginson, D. P.; Park, J.; Pollock, B. B.; Remington, B. A.; Ryutov, D. D.; Ruyer, C.; Sakawa, Y.; Sio, H.; Spitkovsky, A.; Swadling, G. F.; Takabe, H.; Zylstra, A. B.

    2017-04-01

    Many astrophysical systems are effectively "collisionless," that is, the mean free path for collisions between particles is much longer than the size of the system. The absence of particle collisions does not preclude shock formation, however, as shocks can be the result of plasma instabilities that generate and amplify electromagnetic fields. The magnetic fields required for shock formation may either be initially present, for example, in supernova remnants or young galaxies, or they may be self-generated in systems such as gamma-ray bursts (GRBs). In the case of GRB outflows, the Weibel instability is a candidate mechanism for the generation of sufficiently strong magnetic fields to produce shocks. In experiments on the OMEGA Laser, we have demonstrated a quasi-collisionless system that is optimized for the study of the non-linear phase of Weibel instability growth. Using a proton probe to directly image electromagnetic fields, we measure Weibel-generated magnetic fields that grow in opposing, initially unmagnetized plasma flows. The collisionality of the system is determined from coherent Thomson scattering measurements, and the data are compared to similar measurements of a fully collisionless system. The strong, persistent Weibel growth observed here serves as a diagnostic for exploring large-scale magnetic field amplification and the microphysics present in the collisional-collisionless transition.

  3. A Plastic Bottle in Rectosigmoid

    Directory of Open Access Journals (Sweden)

    A. Derakhshanfar

    2007-07-01

    Full Text Available Introduction: Evaluation and treatment of foreign bodies in rectum involves careful history and physical examination. The cases of forced introduction of the objects most commonly are , sexual assault , self – introduced for anal eroticism and accidental insertion.Case Report: We describe a case of a patient with rectal impaction following self administration of a plastic bottle for anal sexual gratification. A 49 years old man was admitted in the emergency department with the history of self introduced a bottle into his rectum physical examination and abdominal X-Ray diagnosed the case as impacted foreign body in rectosigmoid. An attempt was made to deliver the bottle through the rectum but because of high lying big bottle in the sigmoid laporotomy was performed and the bottle was removed though a longitudinal incision on sigmoid colon.Conclusion: Retained rectosigmoid foreign bodies have been encountered more frequently and present a dilemma for management and rarely laporotomy for extraction of foreign bodies was performed.

  4. Prediction of heating rate controlled viscous flow activation energy during spark plasma sintering of amorphous alloy powders

    Science.gov (United States)

    Paul, Tanaji; Harimkar, Sandip P.

    2017-07-01

    The viscous flow behavior of Fe-based amorphous alloy powder during isochronal spark plasma sintering was analyzed under the integrated theoretical background of the Arrhenius and directional structural relaxation models. A relationship between viscous flow activation energy and heating rate was derived. An extension of the pertinent analysis to Ti-based amorphous alloys confirmed the broad applicability of such a relationship for predicting the activation energy for sintering below the glass transition temperature (T g) of the amorphous alloy powders.

  5. Water Flow Experiments

    Indian Academy of Sciences (India)

    This is a simple exercise in elementary fluid dynamics for the undergraduate and the secondary school level. Here, we explore the flow of water through an orifice at the bottom of a cylindri- cal bottle/tank, first through a tube attached to the bottom of the bottle/tank and then without the tube. The experiment is easy to perform.

  6. Radioactivity in French bottled waters

    Energy Technology Data Exchange (ETDEWEB)

    Loyen, J.; Brassac, A.; Augeray, C.; Fayolle, C.; Gleizes, M. [Institut de Radioprotection et de Surete Nucleaire - IRSN (France)

    2014-07-01

    As IRSN is considered as a reference laboratory for radioactivity measurements, French health ministry and French nuclear safety authority asked IRSN to carry out a study in order to get a fresh and complete status of radiological water quality of French bottled waters. The study was carried out during 12 months in 2012. A total of 142 bottled waters samples were analyzed (75 spring waters and 67 natural mineral waters). The laboratories of IRSN were in charge of: - systematic measurement of radioactivity following requirements of the French health ministry (Circulaire du 13/06/2007) regarding the monitoring and management of sanitary risk linked to the presence of radionuclides in drinking waters (natural mineral waters excepted). - systematic uranium mass concentration determination; - a few radon-222 gas measurements for waters in glass bottles. This study is a flash assessment of radiological characteristics of French bottled waters, at the analysis date for the sample received. It was done in informative way and was not done for regulatory control purposes.. This study has shown that: - all bottled waters analyzed have a tritium activity concentration lower than the quality reference value of 100 Bq/l of the French regulation; - More than 105 bottled waters analyzed (80% of the springs waters and 70% of natural mineral waters received) have a gross alpha activity concentration lower than the guideline value of 0,1 Bq/l of the French regulation; - All bottled waters analyzed have a residual gross beta activity concentration lower than the guideline value of 1 Bq/l of the French regulation; - All bottled waters analyzed have a uranium mass concentration lower than the provisory guideline value of 30 μg/l of the WHO for drinking waters; - radon-222 was only significantly measured once upon 6 glass bottled waters with a value far below the reference value of 100 Bq/l of the future European Directive on drinking waters. For 32 bottled waters with gross alpha

  7. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    Science.gov (United States)

    Brust, M.; Aouane, O.; Thiébaud, M.; Flormann, D.; Verdier, C.; Kaestner, L.; Laschke, M. W.; Selmi, H.; Benyoussef, A.; Podgorski, T.; Coupier, G.; Misbah, C.; Wagner, C.

    2014-03-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.

  8. Digital holographic interferometry employing Fresnel transform reconstruction for the study of flow shear stabilized Z-pinch plasmas

    Science.gov (United States)

    Ross, M. P.; Shumlak, U.

    2016-10-01

    The ZaP-HD flow Z-pinch project provides a platform to explore how shear flow stabilized Z-pinches could scale to high-energy-density plasma (plasma with pressures exceeding 1 Mbar) and fusion reactor conditions. The Z-pinch is a linear plasma confinement geometry in which the plasma carries axial electric current and is confined by its self-induced magnetic field. ZaP-HD generates shear stabilized, axisymmetric Z-pinches with stable lifetimes approaching 60 μs. The goal of the project is to increase the plasma density and temperature compared to the previous ZaP project by compressing the plasma to smaller radii (≈1 mm). Radial and axial plasma electron density structure is measured using digital holographic interferometry (DHI), which provides the necessary fine spatial resolution. ZaP-HD's DHI system uses a 2 ns Nd:YAG laser pulse with a second harmonic generator (λ = 532 nm) to produce holograms recorded by a Nikon D3200 digital camera. The holograms are numerically reconstructed with the Fresnel transform reconstruction method to obtain the phase shift caused by the interaction of the laser beam with the plasma. This provides a two-dimensional map of line-integrated electron density, which can be Abel inverted to determine the local number density. The DHI resolves line-integrated densities down to 3 × 1020 m-2 with spatial resolution near 10 μm. This paper presents the first application of Fresnel transform reconstruction as an analysis technique for a plasma diagnostic, and it analyzes the method's accuracy through study of synthetic data. It then presents an Abel inversion procedure that utilizes data on both sides of a Z-pinch local number density profile to maximize profile symmetry. Error estimation and Abel inversion are applied to the measured data.

  9. PET bottle use patterns and antimony migration into bottled water and soft drinks: the case of British and Nigerian bottles.

    Science.gov (United States)

    Tukur, Aminu; Sharp, Liz; Stern, Ben; Tizaoui, Chedly; Benkreira, Hadj

    2012-04-01

    While antimony has been reported to migrate from PET bottles into contents, reports on bottled water and soft drinks usage and PET bottle reuse patterns are currently unavailable in the literature. Bottle use conditions and patterns are important determinants of antimony migration. In this work a survey assessing the pattern of bottle use and reuse in Britain and Nigeria was undertaken. The survey findings influenced the design of laboratory experiments that assessed the migration of antimony from PET bottles into water and soft drinks. Typical storage durations for bottled contents between purchase and opening for use were 7 days or less. However storage of up to one year was reported. Bottle reuse was high and similar for the two countries with reuse durations being higher in Nigeria. The antimony concentration in 32 PET bottle materials from Britain and Nigeria were similar and ranged between 177 and 310 mg kg(-1). For 47 freshly purchased British bottled contents antimony concentration ranged between 0.03 and 6.61 μg L(-1) with only one sample exceeding the EU acceptable limit. Concentrations of Cd, Ge, Zn, Al, Be, Ti, Co and Pb were also measured. At realistic temperatures of 40 and 60 °C antimony concentration in deionised water in bottles remained below the EU acceptable limit even after 48 h exposure. The limit was exceeded for most exposures at 80 °C. Concentration of antimony in some bottled contents exceeded the EU limit after 11 months of storage at room temperature. Bottle aging and increase in bottle volume were associated with decreased migration of antimony from bottles.

  10. 27 CFR 25.142 - Bottles.

    Science.gov (United States)

    2010-04-01

    ... TREASURY LIQUORS BEER Marks, Brands, and Labels § 25.142 Bottles. (a) Label requirements. Each bottle of beer shall show by label or otherwise the name or trade name of the brewer, the net contents of the bottle, the nature of the product such as beer, ale, porter, stout, etc., and the place of production...

  11. 21 CFR 868.5220 - Blow bottle.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blow bottle. 868.5220 Section 868.5220 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5220 Blow bottle. (a) Identification. A blow bottle is a device that is intended for medical purposes to induce a forced expiration from a patient. The patient blows...

  12. 21 CFR 165.110 - Bottled water.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bottled water. 165.110 Section 165.110 Food and... CONSUMPTION BEVERAGES Requirements for Specific Standardized Beverages § 165.110 Bottled water. (a) Identity—(1) Description. Bottled water is water that is intended for human consumption and that is sealed in...

  13. Investigations into the influence of posture on renal plasma flow and glomerular filtration rate during late pregnancy.

    Science.gov (United States)

    Dunlop, W

    1976-01-01

    Renal plasma flow and glomerular filtration rate were investigated in three positions (supine, left lateral and sitting) in a group of eighteen healthy women during late pregnancy and again after the puerperium. No difference in renal function could be attributed to the position adopted. However, an unexplained decrease in both of the indices occurred during the course of prolonged infusion in any position.

  14. Influence of gas flow velocity on the transport of chemical species in an atmospheric pressure air plasma discharge

    Science.gov (United States)

    Hasan, M. I.; Walsh, J. L.

    2017-03-01

    This paper reports on a numerical study of the transport of reactive chemical species generated in an atmospheric-pressure air plasma discharge under the influence of a high velocity flowing gas. Using a 1D air plasma model, it is shown that the reactive species transported downstream of the discharge region can be categorized into three distinct groups based on their spatial distribution: (i) decaying downstream species, (ii) increasing downstream species and (iii) variable density species, where the density is a function of both spatial position and gas flow velocity. It is demonstrated that the gas flow velocity influences the dominant chemical reactions downstream of the discharge region, noticeably altering the composition of several key reactive chemical species transported to a given downstream location. As many emerging applications of atmospheric pressure plasma are driven by the flux of reactive chemical species, this study highlights the importance of gas flow velocity, not only as a means to enhance mass transport but also as a means to manipulate the very nature of the reactive plasma chemistry arriving at a given location.

  15. Enhancement of glomerular filtration rate and renal plasma flow by oral glucose load in well controlled insulin-dependent diabetics

    DEFF Research Database (Denmark)

    Sandahl Christiansen, J; Christensen, C K; Hermansen, K

    1986-01-01

    Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured in 27 patients with uncomplicated insulin-dependent diabetes (IDDM) before and after an oral glucose load of 1.1 g glucose/kg body wt. In the 18 patients showing near-normoglycaemia (blood glucose less than or equal to 8 m...

  16. Wind tunnel experiments on flow separation control of an Unmanned Air Vehicle by nanosecond discharge plasma aerodynamic actuation

    Science.gov (United States)

    Kang, Chen; Hua, Liang

    2016-02-01

    Plasma flow control (PFC) is a new kind of active flow control technology, which can improve the aerodynamic performances of aircrafts remarkably. The flow separation control of an unmanned air vehicle (UAV) by nanosecond discharge plasma aerodynamic actuation (NDPAA) is investigated experimentally in this paper. Experimental results show that the applied voltages for both the nanosecond discharge and the millisecond discharge are nearly the same, but the current for nanosecond discharge (30 A) is much bigger than that for millisecond discharge (0.1 A). The flow field induced by the NDPAA is similar to a shock wave upward, and has a maximal velocity of less than 0.5 m/s. Fast heating effect for nanosecond discharge induces shock waves in the quiescent air. The lasting time of the shock waves is about 80 μs and its spread velocity is nearly 380 m/s. By using the NDPAA, the flow separation on the suction side of the UAV can be totally suppressed and the critical stall angle of attack increases from 20° to 27° with a maximal lift coefficient increment of 11.24%. The flow separation can be suppressed when the discharge voltage is larger than the threshold value, and the optimum operation frequency for the NDPAA is the one which makes the Strouhal number equal one. The NDPAA is more effective than the millisecond discharge plasma aerodynamic actuation (MDPAA) in boundary layer flow control. The main mechanism for nanosecond discharge is shock effect. Shock effect is more effective in flow control than momentum effect in high speed flow control. Project supported by the National Natural Science Foundation of China (Grant Nos. 61503302, 51207169, and 51276197), the China Postdoctoral Science Foundation (Grant No. 2014M562446), and the Natural Science Foundation of Shaanxi Province, China (Grant No. 2015JM1001).

  17. Effect of helium plasma gas flow rate on the properties of WC-12 wt.%Co coatings sprayed by atmospheric plasma

    Directory of Open Access Journals (Sweden)

    Mihailo R. Mrdak

    2014-06-01

    Full Text Available The cermet coatings of WC-12wt.%Co are extensively used to improve the wear resistance of a wide range of technical components. This paper analyses the influence of the plasma gas flow of helium on the microstructure and mechanical properties of WC-12wt.%Co coatings deposited by plasma spraying at atmospheric pressure (APS. In order to obtain homogeneous and denser coatings, three different flows of He ( 8 l/min., 16 l/min. and 32 l/min were used in the research. With the application of He, coatings achieved higher values of hardness due to less degradation of the primary WC carbides. The main goal was to deposit dense and homogeneous layers of WC-12wt.%Co coatings with improved wear resistance for different applications. The test results of the microstructure of the layers were evaluated under a light microscope. The analysis of the microstructure and the mechanical properties of the deposited layers was made in accordance with the standard of Pratt-Whitney. The morphology of the powder particles and the microstructure of the best coating was examined on the SEM (scanning electron microscope. The evaluation of the mechanical properties of the layers was done by applying the HV0.3 method for microhardness testing and by applying tensile testing to test the bond strength. The research has shown that the flow of He plasma gas significantly affects the microstructure, the mechanical properties and the structure of WC-12 wt.%Co coatings.

  18. Miniature magnetic bottle confined by circularly polarized laser light

    Energy Technology Data Exchange (ETDEWEB)

    Kolka, E.; Eliezer, S.; Paiss, Y. [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center

    1995-09-01

    A new concept of hot plasma confinement in a miniature magnetic bottle induced by circularly polarized laser light is suggested. Magnetic fields generated by circularly polarized laser light may be of the order of megagauss. In this configuration the circularly polarized laser light is used to obtain confinement of a plasma contained in a good conductor vessel. The poloidal magnetic field induced by the circularly polarized laser and the efficiency of laser absorption by the plasma are calculated. The confinement in this scheme is supported by the magnetic forces. The Lawson criterion for a DT plasma might be achieved for number density n = 5``centre dot`` 10{sup 21} cm{sup -3} and confinement time {tau} = 20 ns. The laser and plasma parameters required to obtain an energetic gain are calculated. (Author).

  19. Changes in sucking performance from nonnutritive sucking to nutritive sucking during breast- and bottle-feeding.

    Science.gov (United States)

    Mizuno, Katsumi; Ueda, Aki

    2006-05-01

    Our aim was to obtain a better understanding of the differences between breast-feeding and bottle-feeding, particularly with regard to how sucking performance changes from nonnutritive sucking (NNS) to nutritive sucking (NS). Twenty-two normal term infants were studied while breast-feeding at 4 and 5 d postpartum. Five of the 22 infants were exclusively breast-fed, but we tested the other 17 infants while breast-feeding and while bottle-feeding. Before the milk ejection reflex (MER) occurs, little milk is available. As such, infants perform NNS before MER. For bottle-feeding, a one-way valve was affixed between the teat and the bottle so that the infants needed to perform NNS until milk flowed into the teat chamber. At the breast, the sucking pressure (-93.1 +/- 28.3 mm Hg) was higher during NNS compared with NS (-77.3 +/- 27.0 mm Hg). With a bottle, the sucking pressure was lower during NNS (-27.5 +/- 11.2 mm Hg) compared with NS (-87.5 +/- 28.5 mm Hg). Sucking frequency was higher and sucking duration was shorter during NNS compared with that during NS both at the breast and with a bottle. There were significant differences in the changes of sucking pressure and duration from NNS to NS between breast- and bottle-feeding. The change in sucking pressure and duration from NNS to NS differed between breast-feeding and bottle-feeding. Even with a modified bottle and teats, bottle-feeding differs from breast-feeding.

  20. Physics and Chemistry of MW Laser-induced Discharge in Gas Flows and Plasma Jets

    Science.gov (United States)

    2007-12-01

    can be quasi-stationary coaxial plasma accelerators (MPC). This type of accelerators generates plasma jets of different gases (H2, He, N2, Ar) with...gas is ionizing and accelerating in discharge processing. For this regime the plasma gun generates the plasma jets of different gases3 (H2, He, N2...spectrometers. Spectrometers 1 and 2 are used for measuring of time behavior of single spectral lines, emitting in the focus area of plasma gun . Usually

  1. POD analysis of flow over a backward-facing step forced by right-angle-shaped plasma actuator.

    Science.gov (United States)

    Wang, Bin; Li, Huaxing

    2016-01-01

    This study aims to present flow control over the backward-facing step with specially designed right-angle-shaped plasma actuator and analyzed the influence of various scales of flow structures on the Reynolds stress through snapshot proper orthogonal decomposition (POD). 2D particle image velocimetry measurements were conducted on region (x/h = 0-2.25) and reattachment zone in the x-y plane over the backward-facing step at a Reynolds number of Re h  = 27,766 (based on step height [Formula: see text] and free stream velocity [Formula: see text]. The separated shear layer was excited by specially designed right-angle-shaped plasma actuator under the normalized excitation frequency St h  ≈ 0.345 along the 45° direction. The spatial distribution of each Reynolds stress component was reconstructed using an increasing number of POD modes. The POD analysis indicated that the flow dynamic downstream of the step was dominated by large-scale flow structures, which contributed to streamwise Reynolds stress and Reynolds shear stress. The intense Reynolds stress localized to a narrow strip within the shear layer was mainly affected by small-scale flow structures, which were responsible for the recovery of the Reynolds stress peak. With plasma excitation, a significant increase was obtained in the vertical Reynolds stress peak. Under the dimensionless frequencies St h  ≈ 0.345 and [Formula: see text] which are based on the step height and momentum thickness, the effectiveness of the flow control forced by the plasma actuator along the 45° direction was ordinary. Only the vertical Reynolds stress was significantly affected.

  2. From Blogs to Bottle Caps

    Science.gov (United States)

    Edinger, Ted

    2012-01-01

    There is a wonderful community of art educators connecting a once-isolated profession through blogging. Art educators around the world are sharing ideas and communicating with their peers through this amazing resource. In this article, the author describes the bottle cap mural at Tulip Grove Elementary School which was inspired by this exchange of…

  3. Management of complex data flows in the ASDEX Upgrade plasma control system

    Energy Technology Data Exchange (ETDEWEB)

    Treutterer, Wolfgang, E-mail: Wolfgang.Treutterer@ipp.mpg.de [Max-Planck Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Neu, Gregor; Raupp, Gerhard; Zasche, Dieter; Zehetbauer, Thomas [Max-Planck Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Cole, Richard; Lueddecke, Klaus [Unlimited Computer Systems, Iffeldorf (Germany)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Control system architectures with data-driven workflows are efficient, flexible and maintainable. Black-Right-Pointing-Pointer Signal groups provide coherence of interrelated signals and increase the efficiency of process synchronisation. Black-Right-Pointing-Pointer Sample tags indicating sample quality form the fundament of a local event handling strategy. Black-Right-Pointing-Pointer A self-organising workflow benefits from sample tags consisting of time stamp and stream activity. - Abstract: Establishing adequate technical and physical boundary conditions for a sustained nuclear fusion reaction is a challenging task. Phased feedback control and monitoring for heating, fuelling and magnetic shaping is mandatory, especially for fusion devices aiming at high performance plasmas. Technical and physical interrelations require close collaboration of many components in sequential as well as in parallel processing flows. Moreover, handling of asynchronous, off-normal events has become a key element of modern plasma performance optimisation and machine protection recipes. The manifoldness of plasma states and events, the variety of plant system operation states and the diversity in diagnostic data sampling rates can hardly be mastered with a rigid control scheme. Rather, an adaptive system topology in combination with sophisticated synchronisation and process scheduling mechanisms is suited for such an environment. Moreover, the system is subject to real-time control constraints: response times must be deterministic and adequately short. Therefore, the experimental tokamak device ASDEX Upgrade employs a discharge control system DCS, whose core has been designed to meet these requirements. In the paper we will compare the scheduling schemes for the parallelised realisation of a control workflow and show the advantage of a data-driven workflow over a managed workflow. The data-driven workflow as used in DCS is based on signals

  4. Electromagnetic radiation and nonlinear energy flow in an electron beam-plasma system

    Science.gov (United States)

    Whelan, D. A.; Stenzel, R. L.

    1985-01-01

    It is shown that the unstable electron-plasma waves of a beam-plasma system can generate electromagnetic radiation in a uniform plasma. The generation mechanism is a scattering of the unstable electron plasma waves off ion-acoustic waves, producing electromagnetic waves whose frequency is near the local plasma frequency. The wave vector and frequency matching conditions of the three-wave mode coupling are experimentally verified. The electromagnetic radiation is observed to be polarized with the electric field parallel to the beam direction, and its source region is shown to be localized to the unstable plasma wave region. The frequency spectrum shows negligible intensity near the second harmonic of the plasma frequency. These results suggest that the observed electromagnetic radiation of type III solar bursts may be generated near the local plasma frequency and observed downstream where the wave frequency is near the harmonic of the plasma frequency.

  5. Ionospheric plasma flow about a system of electrically biased flat plates. M.S. Thesis - Cleveland State Univ. Final Report

    Science.gov (United States)

    Herr, Joel L.

    1993-01-01

    The steady state interaction of two electrically biased parallel plates immersed in a flowing plasma characteristic of low earth orbit is studied numerically. Fluid equations are developed to describe the motion of the cold positively charged plasma ions, and are solved using finite-differences in two dimensions on a Cartesian grid. The behavior of the plasma electrons is assumed to be described by the Maxwell-Boltzmann distribution. Results are compared to an analytical and a particle simulation technique for a simplified flow geometry consisting of a single semi-infinite negatively biased plate. Comparison of the extent of the electrical disturbance into the flowing plasma and the magnitude of the current collected by the plate is very good. The interaction of two equally biased parallel plates is studied as a function of applied potential. The separation distance at which the current collected by either plate decreases by five and twenty percent is determined as a function of applied potential. The percent decreases were based on a non-interacting case. The decrease in overall current is caused by a decrease in ionic density in the region between the plates. As the separation between the plates decreases, the plates collect the ions at a faster rate than they are supplied to the middle region by the oncoming plasma flow. The docking of spacecraft in orbit is simulated by moving two plates of unequal potential toward one another in a quasi-static manner. One plate is held at a large negative potential while the other floats electrically in the resulting potential field. It is found that the floating plate does not charge continuously negative as it approaches the other more negatively biased plate. Instead, it charges more and then less negative as ionic current decreases and then increases respectively upon approach. When the two plates come into contact, it is expected that the electrically floating plate will charge rapidly negative to a potential near that of

  6. Long-term variations in the intensity of polar cap plasma flows inferred from SuperDARN

    Science.gov (United States)

    Koustov, A. V.; Fiori, R. A. D.; Abooali zadeh, Z.

    2015-11-01

    Multiyear (1995-2013) velocity data collected by the Super Dual Auroral Network (SuperDARN) HF radars are considered to investigate the diurnal, seasonal, and solar cycle variation of the polar cap plasma flow speed. By considering monthly data sets, we show that the flows are systematically faster in the dawn/prenoon sector. The effect is particularly strong for interplanetary magnetic field (IMF) Bz 0 and in summer months. For Bz Bt at a rate of 20-30 m/s/nT during near noon summer hours. The dependence is weaker for other seasons and away from noon. For IMF Bz > 0, the flow speed response to the increase in Bt is weak. Despite the general sensitivity of the flow speed to Bt intensity and season, the speed for specific IMF bins and seasons or the speed averaged over a year does not change much over the solar cycle. Overall, the velocity is reduced during years of lowest solar activity, but a progression of the effect throughout the solar cycle was not observed. Inferred diurnal and seasonal trends of the polar cap flow speed are generally consistent with variations in the occurrence of VHF echoes whose onset depends on the strength of the ionospheric electric field or equivalently the magnitude of the plasma flow speed.

  7. Isotope Effects on Trapped-Electron-Mode Driven Turbulence and Zonal Flows in Helical and Tokamak Plasmas.

    Science.gov (United States)

    Nakata, Motoki; Nunami, Masanori; Sugama, Hideo; Watanabe, Tomo-Hiko

    2017-04-21

    Impacts of isotope ion mass on trapped-electron-mode (TEM)-driven turbulence and zonal flows in magnetically confined fusion plasmas are investigated. Gyrokinetic simulations of TEM-driven turbulence in three-dimensional magnetic configuration of helical plasmas with hydrogen isotope ions and real-mass kinetic electrons are realized for the first time, and the linear and the nonlinear nature of the isotope and collisional effects on the turbulent transport and zonal-flow generation are clarified. It is newly found that combined effects of the collisional TEM stabilization by the isotope ions and the associated increase in the impacts of the steady zonal flows at the near-marginal linear stability lead to the significant transport reduction with the opposite ion mass dependence in comparison to the conventional gyro-Bohm scaling. The universal nature of the isotope effects on the TEM-driven turbulence and zonal flows is verified for a wide variety of toroidal plasmas, e.g., axisymmetric tokamak and non-axisymmetric helical or stellarator systems.

  8. Interaction between sheared flows and turbulent transport in magnetized fusion-grade plasmas; Interaction entre ecoulements cisailles et transport turbulent dans les plasmas de fusion magnetique

    Energy Technology Data Exchange (ETDEWEB)

    Leconte, M.

    2008-11-15

    The H confinement regime is set when the heating power reaches a threshold value P{sub c} and is linked to the formation of a transport barrier in the edge region of the plasma. Such a barrier is characterized by a high pressure gradient and is submitted to ELM (edge localized mode) instabilities. ELM instabilities trigger violent quasi-periodical ejections of matter and heat that induce quasi-periodical relaxations of the transport barrier called relaxation oscillations. In this work we studied the interaction between sheared flows and turbulence in fusion plasmas. In particular, we studied the complex dynamics of a transport barrier and we show through a simulation that resonant magnetic perturbations could control relaxation oscillations without a significant loss of confinement

  9. Monitoring nano-flow rate of water by atomic emission detection using helium radio-frequency plasma.

    Science.gov (United States)

    Nakagama, Tatsuro; Maeda, Tsuneaki; Uchiyama, Katsumi; Hobo, Toshiyuki

    2003-06-01

    Recently, high-performance nano-scale flow pumping systems have been developed for micro and miniaturized analysis systems. A novel device capable of measuring and monitoring nanoliter scale flow rates has been required for the further development of the pumping system. In this study, an atomic emission detector using helium radio-frequency plasma (RFP-AED) was used for the measurement of the nanoliter scale flow rate of water by quantitatively detecting the emission from hydrogen in the water molecules. Monitoring nano-flow rates of water in the range up to 1.0 microl min(-1), and the change in the flow rate by the indication of the ratio of the emissions of H (656.3 nm) and He (667.8 nm) were successful. At present, the lowest flow rate that could be determined reproducibly was 4 nl min(-1) calculated as five times the standard deviation of the background noise. Additionally, similar evaluations for the deviation of each flow rate by using the RFP-AED and a flow-injection system were produced.

  10. Self-consistent plasma chemistry model for surface microdischarge in humid air including effects of ohmic heating and gas flow

    Science.gov (United States)

    Yi, Changho; Yoon, Sung-Young; Eom, Sangheum; Park, Seungil; Kim, Seong Bong; Ryu, Seungmin; Yoo, Suk Jae

    2017-10-01

    A numerical model is presented for surface microdischarges (SMDs) in flowing humid air at atmospheric pressure, to investigate the effects of the direct ohmic heating of gases in the discharge layer, and the transports of heat and particles by gas flow. Using a simplified configuration of heat transfer and gas flow, the proposed model calculated not only the densities of neutral species but also the temperatures of gases as time dependent variables. The calculated dynamics for various reactive oxygen and nitrogen species showed reasonable agreement with the experimental results obtained by Fourier transformed infrared absorption spectroscopy, while the calculated dynamics without ohmic heating of gases in the discharge layer showed significant disagreement. These results imply that local ohmic heating of the thin discharge layer by the microdischarge itself considerably affected the rate constants of the temperature dependent chemical reactions. The dynamics of the neutral species were also affected by gas flow, both directly through particle transport, and indirectly through cooling. Accordingly, to properly simulate the dynamics of reactive neutral species in SMDs, plasma chemistry models should treat plasmas as sources of both particles and heat which can be deliberately transported by gas flow.

  11. On the nozzle geometry of a transferred plasma cutting torch for the arc stabilization with swirl flow

    OpenAIRE

    Sakuragi, Shunichi; 桜木, 俊一

    1995-01-01

    In the plasma cutting process, the arcjet with high specific energy is required to get good cut quality in the dross-free cutting. For this purpose, it is necessary to stabilize the arc with gas flow rate lower than the conventional torches. The present paper discusses the nozzle shape that effectively stabilizes the arc by the swirl flow. The pressure measurement inside the large-scale model-nozzle indicates that the nozzle shape can be optimized to create a large pressure gradient for the a...

  12. Dissipated power and induced velocity fields data of a micro single dielectric barrier discharge plasma actuator for active flow control

    Directory of Open Access Journals (Sweden)

    E. Pescini

    2015-12-01

    Full Text Available In recent years, single dielectric barrier discharge (SDBD plasma actuators have gained great interest among all the active flow control devices typically employed in aerospace and turbomachinery applications [1,2]. Compared with the macro SDBDs, the micro single dielectric barrier discharge (MSDBD actuators showed a higher efficiency in conversion of input electrical power to delivered mechanical power [3,4]. This article provides data regarding the performances of a MSDBD plasma actuator [5,6]. The power dissipation values [5] and the experimental and numerical induced velocity fields [6] are provided. The present data support and enrich the research article entitled “Optimization of micro single dielectric barrier discharge plasma actuator models based on experimental velocity and body force fields” by Pescini et al. [6].

  13. Elimination of numerical Cherenkov instability in flowing-plasma particle-in-cell simulations by using Galilean coordinates.

    Science.gov (United States)

    Lehe, Remi; Kirchen, Manuel; Godfrey, Brendan B; Maier, Andreas R; Vay, Jean-Luc

    2016-11-01

    Particle-in-cell (PIC) simulations of relativistic flowing plasmas are of key interest to several fields of physics (including, e.g., laser-wakefield acceleration, when viewed in a Lorentz-boosted frame) but remain sometimes infeasible due to the well-known numerical Cherenkov instability (NCI). In this article, we show that, for a plasma drifting at a uniform relativistic velocity, the NCI can be eliminated by simply integrating the PIC equations in Galilean coordinates that follow the plasma (also sometimes known as comoving coordinates) within a spectral analytical framework. The elimination of the NCI is verified empirically and confirmed by a theoretical analysis of the instability. Moreover, it is shown that this method is applicable both to Cartesian geometry and to cylindrical geometry with azimuthal Fourier decomposition.

  14. Dissipated power and induced velocity fields data of a micro single dielectric barrier discharge plasma actuator for active flow control.

    Science.gov (United States)

    Pescini, E; Martínez, D S; De Giorgi, M G; Francioso, L; Ficarella, A

    2015-12-01

    In recent years, single dielectric barrier discharge (SDBD) plasma actuators have gained great interest among all the active flow control devices typically employed in aerospace and turbomachinery applications [1,2]. Compared with the macro SDBDs, the micro single dielectric barrier discharge (MSDBD) actuators showed a higher efficiency in conversion of input electrical power to delivered mechanical power [3,4]. This article provides data regarding the performances of a MSDBD plasma actuator [5,6]. The power dissipation values [5] and the experimental and numerical induced velocity fields [6] are provided. The present data support and enrich the research article entitled "Optimization of micro single dielectric barrier discharge plasma actuator models based on experimental velocity and body force fields" by Pescini et al. [6].

  15. Boundary conditions on the plasma emitter surface in the presence of a particle counter flow: I. Ion emitter

    Energy Technology Data Exchange (ETDEWEB)

    Astrelin, V. T., E-mail: V.T.Astrelin@inp.nsk.su; Kotelnikov, I. A. [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation)

    2017-02-15

    Emission of positively charged ions from a plasma emitter irradiated by a counterpropagating electron beam is studied theoretically. A bipolar diode with a plasma emitter in which the ion temperature is lower than the electron temperature and the counter electron flow is extracted from the ion collector is calculated in the one-dimensional model. An analog of Bohm’s criterion for ion emission in the presence of a counterpropagating electron beam is derived. The limiting density of the counterpropagating beam in a bipolar diode operating in the space-charge-limited-emission regime is calculated. The full set of boundary conditions on the plasma emitter surface that are required for operation of the high-current optics module in numerical codes used to simulate charged particle sources is formulated.

  16. Influence of gas flow and applied voltage on interaction of jets in a cross-field helium plasma jet array

    Science.gov (United States)

    Wan, Meng; Liu, Feng; Fang, Zhi; Zhang, Bo; Wan, Hui

    2017-09-01

    Atmospheric Pressure Plasma Jet arrays can greatly enhance the treatment area to fulfill the need for large-scale surface processing, while the spatial uniformity of the plasma jet array is closely related to the interactions of the adjacent jets. In this paper, a three-tube one-dimensional (1D) He plasma jet array with a cross-field needle-ring electrode structure is used to investigate the influences of the gas flow rate and applied voltage on the interactions of the adjacent jets through electrical, optical, and fluid measurements. The repulsion of the adjacent plume channels is observed using an intensified charge-coupled device (ICCD) and the influence of the gas flow rate and applied voltage on the electrostatic repulsion force, Coulomb force, is discussed. It is found that electrical coupling, mainly electrostatic repulsion force, exists among the jets in the array, which causes both the divergence of the lateral plumes and the nonlinear changes of the discharge power and the transport charge. The deflection angle of the lateral plumes with respect to the central plume in the optical images increases with the increase of applied voltage and decreases with the increase of gas flow rate. The deflection angle of the lateral plumes in the optical images is obviously larger than that of the lateral gas streams in the Schlieren images under the same experimental conditions, and the unconformity of the deflection angles is mainly attributed to the electrostatic repulsion force in adjacent plasma plume channels. The experimental results can help understand the interaction mechanisms of jets in the array and design controllable and scalable plasma jet arrays.

  17. Comparison of standard- and nano-flow liquid chromatography platforms for MRM-based quantitation of putative plasma biomarker proteins.

    Science.gov (United States)

    Percy, Andrew J; Chambers, Andrew G; Yang, Juncong; Domanski, Dominik; Borchers, Christoph H

    2012-09-01

    The analytical performance of a standard-flow ultra-high-performance liquid chromatography (UHPLC) and a nano-flow high-performance liquid chromatography (HPLC) system, interfaced to the same state-of-the-art triple-quadrupole mass spectrometer, were compared for the multiple reaction monitoring (MRM)-mass spectrometry (MS)-based quantitation of a panel of 48 high-to-moderate-abundance cardiovascular disease-related plasma proteins. After optimization of the MRM transitions for sensitivity and testing for chemical interference, the optimum sensitivity, loading capacity, gradient, and retention-time reproducibilities were determined. We previously demonstrated the increased robustness of the standard-flow platform, but we expected that the standard-flow platform would have an overall lower sensitivity. This study was designed to determine if this decreased sensitivity could be compensated for by increased sample loading. Significantly fewer interferences with the MRM transitions were found for the standard-flow platform than for the nano-flow platform (2 out of 103 transitions compared with 42 out of 103 transitions, respectively), which demonstrates the importance of interference-testing when nano-flow systems are used. Using only interference-free transitions, 36 replicate LC/MRM-MS analyses resulted in equal signal reproducibilities between the two platforms (9.3 % coefficient of variation (CV) for 88 peptide targets), with superior retention-time precision for the standard-flow platform (0.13 vs. 6.1 % CV). Surprisingly, for 41 of the 81 proteotypic peptides in the final assay, the standard-flow platform was more sensitive while for 9 of 81 the nano-flow platform was more sensitive. For these 81 peptides, there was a good correlation between the two sets of results (R(2) = 0.98, slope = 0.97). Overall, the standard-flow platform had superior performance metrics for most peptides, and is a good choice if sufficient sample is available.

  18. Enhanced nonlinear iterative techniques applied to a non-equilibrium plasma flow

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, D.A.; McHugh, P.R. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1996-12-31

    We study the application of enhanced nonlinear iterative methods to the steady-state solution of a system of two-dimensional convection-diffusion-reaction partial differential equations that describe the partially-ionized plasma flow in the boundary layer of a tokamak fusion reactor. This system of equations is characterized by multiple time and spatial scales, and contains highly anisotropic transport coefficients due to a strong imposed magnetic field. We use Newton`s method to linearize the nonlinear system of equations resulting from an implicit, finite volume discretization of the governing partial differential equations, on a staggered Cartesian mesh. The resulting linear systems are neither symmetric nor positive definite, and are poorly conditioned. Preconditioned Krylov iterative techniques are employed to solve these linear systems. We investigate both a modified and a matrix-free Newton-Krylov implementation, with the goal of reducing CPU cost associated with the numerical formation of the Jacobian. A combination of a damped iteration, one-way multigrid and a pseudo-transient continuation technique are used to enhance global nonlinear convergence and CPU efficiency. GMRES is employed as the Krylov method with Incomplete Lower-Upper(ILU) factorization preconditioning. The goal is to construct a combination of nonlinear and linear iterative techniques for this complex physical problem that optimizes trade-offs between robustness, CPU time, memory requirements, and code complexity. It is shown that a one-way multigrid implementation provides significant CPU savings for fine grid calculations. Performance comparisons of the modified Newton-Krylov and matrix-free Newton-Krylov algorithms will be presented.

  19. Evaluation function of drinking ease from aluminum beverage bottles relative to optimum bottle opening diameter and beverage type.

    Science.gov (United States)

    Chihara, Takanori; Yamazaki, Koetsu

    2012-01-01

    In recent years, aluminum beverage bottles having screw tops with opening diameters of 28 and 38 mm have been launched in the Japanese market in keeping with the modern-day drinking habits of consumers. Although Japanese consumers are familiar with such bottles, a majority of them feel that the 28 mm opening is too small and the 38 mm opening is too large. Therefore, we felt the need to develop a method for evaluating consumer feelings when they drink a beverage directly from the bottle opening. For this purpose, we propose an evaluation function of drinking ease that calculates the optimum opening diameter of the bottle. From results of our previous study, we know that there exists an ideal volume of beverage flowing into the mouth, at which consumers feel most comfortable while drinking directly from bottles. Therefore, we define the evaluation function of drinking ease in terms of the difference between the actual volume of fluid in the mouth and the expected ideal volume. If this difference is small, consumers probably feel comfortable while drinking the beverage. We consider a design variable, i.e., the opening diameter, and two state variables, i.e., the volume of beverage remaining in the bottle and the height of consumers, and construct the response surface of the evaluation function by using radial basis function networks. In addition, for investigating the influence of beverage type on the evaluation function, we select green tea and a carbonated beverage (Coke) as test beverages. Results of optimization of the proposed function show that when the opening diameters are 35.4 mm and 34.4 mm in the case of green tea and Coke, respectively, the actual volume of fluid in the mouth is closest to the ideal volume and the participants feel most comfortable. These results are in agreement with results of our previous study that an opening diameter of 33 mm is optimum for young Japanese adults. Thus, we confirm that the proposed function is accurate; it can be used

  20. Finite element study of three dimensional radiative nano-plasma flow subject to Hall and ion slip currents

    Science.gov (United States)

    Nawaz, M.; Zubair, T.

    In this article, we developed a computer code of Galerikan Finite Element method (GFEM) for three dimensional flow equations of nano-plasma fluid (blood) in the presence of uniform applied magnetic field when Hall and ion slip current are significant. Lorentz force is calculated through generalized Ohm's law with Maxwell equations. A series of numerical simulations are carried out to search ηmax and algebraic equations are solved by Gauss-Seidel method with simulation tolerance 10-8 . Simulated results for special case have an excellent agreement with the already published results. Velocity components and temperature of the nano-plasma (blood) are influenced significantly by the inclusion of nano-particles of Copper (Cu) and Silver (Ag). Heat enhancement is observed when copper and silver nonmagnetic nanoparticles are used instead of simple base fluid (conventional fluid). Radiative nature of nano-plasma in the presence of magnetic field causes a decrease in the temperature due to the transfer of heat by the electromagnetic waves. In contrast to this, due to heat dissipated by Joule heating and viscous dissipation phenomena, temperature of nano-plasmaincreases as thermal radiation parameter is increased. Thermal boundary layer thickness can be controlled by using radiative fluid instead of non-radiative fluid. Momentum boundary layer thickness can be reduced by increasing the intensity of the applied magnetic field. Temperature of plasma in the presence magnetic field is higher than the plasma in the absence of magnetic field.

  1. Associations between bottle-feeding intensity and maternal encouragement of bottle-emptying.

    Science.gov (United States)

    Ventura, Alison K; Garcia, Patsy; Schaffner, Andrew A

    2017-12-01

    To explore longitudinal associations between bottle-feeding and maternal encouragement of infant bottle-emptying during the first 6 months of infancy. Mothers completed questionnaires during the third trimester of pregnancy, then monthly during the first 6 months postpartum. Questionnaires assessed family demographics, maternal and infant weight status, infant feeding patterns and maternal encouragement of infant bottle-emptying. The Infant Feeding Practices Study 2, conducted by the US Centers for Disease Control and Prevention and the Food and Drug Administration. Mothers (n 1776). Repeated-measures regression was used to explore associations between bottle-feeding intensity (BFI; defined as the percentage of daily feedings that were from a bottle) and encouragement of bottle-emptying. Mothers who reported consistently high or consistently low BFI also exhibited consistently higher or lower frequency of encouraging their infants to empty the bottle (respectively) across the first 6 months of infancy, whereas mothers who reported increases in their BFI also exhibited concomitant increases in the frequency to which they encouraged their infants to finish the bottle. More frequent encouragement of bottle-emptying was also associated with feeding expressed breast milk (Pbottles for infant feeding was significantly associated with more frequent encouragement of bottle-emptying. Further research using causal designs is needed to better understand whether the use of bottles promotes this controlling feeding practice or whether mothers with more controlling feeding practices opt to bottle-feed.

  2. Oscillations in a half-empty bottle

    Science.gov (United States)

    Bourges, Andréane; Chardac, Amélie; Caussarieu, Aude; Plihon, Nicolas; Taberlet, Nicolas

    2018-02-01

    When a half-empty bottle of water is pushed to roll on a flat surface, the oscillations of the fluid inside the bottle induce an overall jerky motion. These velocity fluctuations of the bottle are studied through simple laboratory experiments accessible to undergraduate students and can help them to grasp fundamental concepts in mechanics and hydrodynamics. We first demonstrate through an astute experiment that the rotation of the fluid and the bottle is decoupled. The equations of motion are then derived using a mechanical approach, while the hydrodynamics of the fluid motion is explained. Finally, the theory is tested against two benchmark experiments.

  3. Acoustic Emission Test for Aircraft Halon 1301 Fire Extinguisher Bottles

    Science.gov (United States)

    1998-04-01

    An acoustic emission test for aircraft Halon 1301 bottles has been developed, a prototype acoustic emission test system constructed, and over 200 used bottles tested at the repair facilities of the two manufacturers of these bottles. The system monit...

  4. The influence of pet containers on antimony concentration in bottled drinking water

    Directory of Open Access Journals (Sweden)

    Perić-Grujić Aleksandra A.

    2010-01-01

    Full Text Available Antimony trioxide (Sb2O3 is the most frequently used catalyst in the polyethylene terephthalate (PET manufacture. As a result, antimony is incorporated into PET bottles at concentration level of 100-300 mg/kg. PET containers are used for drinking water and beverages, as well as food packaging and in the pharmaceutical industry. Thus, it is important to understand the factors that may influence the release of antimony from the catalysts into water and other products, since antimony is potentially toxic trace element. In this paper, the antimony content in nine brands of bottled mineral and spring water from Serbia, and seven brands of bottled mineral and spring water from EU countries was analyzed. The measurements were conducted using the inductively coupled plasma-mass spectrometry (ICP-MS technique. In the all examined samples the antimony concentration was bellow the maximum contaminant level of 5 μg/L prescribed by the Serbian and EU regulations. Comparison of the content of antimony in PET bottled waters with the content of antimony in water bottled commercially in glass and the natural content of antimony in pristine groundwaters, provides explicit evidence of antimony leaching from PET containers. Since waters bottled in PET have much greater concentration ratio of Sb to Pb than corresponding pristine groundwaters, it can be assumed that bottled waters cannot be used as the relavant source for the study of the natural antimony content in groundwaters. There is a clear relation between the quality of water in bottles (composition, ion strength and antimony leaching rate. Moreover, while the rate of antimony leaching is slow at temperatures below 60 oC, at the temperature range of 60-80 oC antimony release occurs and reaches maximum contaminant level rapidly. As antimony can cause both acute and chronic health problems, factors that promote the increase of antimony concentration should be avoided.

  5. Prostate extracellular vesicles in patient plasma as a liquid biopsy platform for prostate cancer using nanoscale flow cytometry

    Science.gov (United States)

    Al-Zahrani, Ali A.; Pardhan, Siddika; Brett, Sabine I.; Guo, Qiu Q.; Yang, Jun; Wolf, Philipp; Power, Nicholas E.; Durfee, Paul N.; MacMillan, Connor D.; Townson, Jason L.; Brinker, Jeffrey C.; Fleshner, Neil E.; Izawa, Jonathan I.; Chambers, Ann F.; Chin, Joseph L.; Leong, Hon S.

    2016-01-01

    Background Extracellular vesicles released by prostate cancer present in seminal fluid, urine, and blood may represent a non-invasive means to identify and prioritize patients with intermediate risk and high risk of prostate cancer. We hypothesize that enumeration of circulating prostate microparticles (PMPs), a type of extracellular vesicle (EV), can identify patients with Gleason Score≥4+4 prostate cancer (PCa) in a manner independent of PSA. Patients and Methods Plasmas from healthy volunteers, benign prostatic hyperplasia patients, and PCa patients with various Gleason score patterns were analyzed for PMPs. We used nanoscale flow cytometry to enumerate PMPs which were defined as submicron events (100-1000nm) immunoreactive to anti-PSMA mAb when compared to isotype control labeled samples. Levels of PMPs (counts/μL of plasma) were also compared to CellSearch CTC Subclasses in various PCa metastatic disease subtypes (treatment naïve, castration resistant prostate cancer) and in serially collected plasma sets from patients undergoing radical prostatectomy. Results PMP levels in plasma as enumerated by nanoscale flow cytometry are effective in distinguishing PCa patients with Gleason Score≥8 disease, a high-risk prognostic factor, from patients with Gleason Score≤7 PCa, which carries an intermediate risk of PCa recurrence. PMP levels were independent of PSA and significantly decreased after surgical resection of the prostate, demonstrating its prognostic potential for clinical follow-up. CTC subclasses did not decrease after prostatectomy and were not effective in distinguishing localized PCa patients from metastatic PCa patients. Conclusions PMP enumeration was able to identify patients with Gleason Score ≥8 PCa but not patients with Gleason Score 4+3 PCa, but offers greater confidence than CTC counts in identifying patients with metastatic prostate cancer. CTC Subclass analysis was also not effective for post-prostatectomy follow up and for

  6. Low gas flow inductively coupled plasma optical emission spectrometry for the analysis of food samples after microwave digestion.

    Science.gov (United States)

    Nowak, Sascha; Gesell, Monika; Holtkamp, Michael; Scheffer, Andy; Sperling, Michael; Karst, Uwe; Buscher, Wolfgang

    2014-11-01

    In this work, the recently introduced low flow inductively coupled plasma optical emission spectrometry (ICP-OES) with a total argon consumption below 0.7 L/min is applied for the first time to the field of food analysis. One goal is the investigation of the performance of this low flow plasma compared to a conventional ICP-OES system when non-aqueous samples with a certain matrix are introduced into the system. For this purpose, arsenic is determined in three different kinds of fish samples. In addition several nutrients (K, Na, Mg, Ca) and trace metals (Co, Cu, Mn, Cd, Pb, Zn, Fe, and Ni) are determined in honey samples (acacia) after microwave digestion. The precision of the measurements is characterized by relative standard deviations (RSD) and compared to the corresponding precision values achieved using the conventional Fassel-type torch of the ICP. To prove the accuracy of the low flow ICP-OES method, the obtained data from honey samples are validated by a conventional ICP-OES. For the measurements concerning arsenic in fish, the low flow ICP-OES values are validated by conventional Fassel-type ICP-OES. Furthermore, a certified reference material was investigated with the low gas flow setup. Limits of detection (LOD), according to the 3σ criterion, were determined to be in the low microgram per liter range for all analytes. Recovery rates in the range of 96-106% were observed for the determined trace metal elements. It was proven that the low gas flow ICP-OES leads to results that are comparable with those obtained with the Fassel-type torch for the analysis of food samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Combining asymmetrical flow field-flow fractionation with light-scattering and inductively coupled plasma mass spectrometric detection for characterization of nanoclay used in biopolymer nanocomposites

    DEFF Research Database (Denmark)

    Schmidt, Bjørn; Petersen, Jens Højslev; Koch, C. Bender

    2009-01-01

    It is expected that biopolymers obtained from renewable resources will in due course become fully competitive with fossil fuel-derived plastics as food-packaging materials. In this context, biopolymer nanocomposites are a field of emerging interest since such materials can exhibit improved...... mechanical and barrier properties and be more suitable for a wider range of food-packaging applications. Natural or synthetic clay nanofillers are being investigated for this purpose in a project called NanoPack funded by the Danish Strategic Research Council. In order to detect and characterize the size...... of clay nanoparticulates, an analytical system combining asymmetrical flow field-flow fractionation (AF4) with multi-angle light-scattering detection (MALS) and inductively coupled plasma mass spectrometry (ICP-MS) is presented. In a migration study, we tested a biopolymer nanocomposite consisting...

  8. Effect of disodium cromoglycate (DSCG) and antihistamines on postirradiation cerebral blood flow and plasma levels of histamine and neurotensin

    Energy Technology Data Exchange (ETDEWEB)

    Cockerham, L.G.; Pautler, E.L.; Carraway, R.E.; Cochrane, D.E.; Hampton, J.D.

    1988-02-01

    In an attempt to elucidate mechanisms underlying the irradiation-induced decrease in regional cerebral blood flow (rCBF) in primates, hippocampal and visual cortical blood flows of rhesus monkeys were measured by hydrogen clearance, before and after exposure to 100 Gy, whole-body, gamma irradiation. Systemic blood pressures were monitored simultaneously. Systemic arterial plasma histamine and neurotensin levels were determined preirradiation and postirradiation. Compared to control animals, the irradiated monkeys exhibited an abrupt decline in systemic blood pressure to 23% of the preirradiation level within 10 min postirradiation, falling to 12% by 60 min. A decrease in hippocampal blood flow to 32% of the preirradiation level was noted at 10 min postirradiation, followed by a slight recovery to 43% at 30 min and a decline to 23% by 60 min. The cortical blood flow for the same animals showed a steady decrease to 29% of the preirradiation levels by 60 min postirradiation. Animals given the mast cell stabilizer disodium cromoglycate and the antihistamines mepyramine and cimetidine before irradiation did not exhibit an abrupt decline in blood pressure but displayed a gradual decrease to a level 33% below preirradiation levels by 60 min postirradiation. Also, the treated, irradiated monkeys displayed rCBF values that were not significantly different from the nonirradiated controls. The plasma neurotensin levels in the irradiated animals, treated and untreated, indicated a nonsignificant postirradiation increase above control levels. However, the postirradiation plasma histamine levels in both irradiated groups showed an increase of approximately 1600% above the preirradiation levels and the postirradiation control levels.

  9. Magnetic flux pile-up and ion heating in a current sheet formed by colliding magnetized plasma flows

    Science.gov (United States)

    Suttle, L.; Hare, J.; Lebedev, S.; Ciardi, A.; Loureiro, N.; Niasse, N.; Burdiak, G.; Clayson, T.; Lane, T.; Robinson, T.; Smith, R.; Stuart, N.; Suzuki-Vidal, F.

    2017-10-01

    We present data from experiments carried out at the Magpie pulsed power facility, which show the detailed structure of the interaction of counter-streaming magnetized plasma flows. In our quasi-2D setup, continuous supersonic flows are produced with strong embedded magnetic fields of opposing directions. Their interaction leads to the formation of a dense and long-lasting current sheet, where we observe the pile-up of the magnetic flux at the sheet boundary, as well as the annihilation of field inside, accompanied by an increase in plasma temperature. Spatially resolved measurements with Faraday rotation polarimetry, B-dot probes, XUV imaging, Thomson scattering and laser interferometry diagnostics show the detailed distribution of the magnetic field and other plasma parameters throughout the system. This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) Grant No. EP/G001324/1, and by the U.S. Department of Energy (DOE) Awards No. DE-F03-02NA00057 and No. DE-SC-0001063.

  10. Improvement of the Performance of Graphite Felt Electrodes for Vanadium-Redox-Flow-Batteries by Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Eva-Maria Hammer

    2014-02-01

    Full Text Available In the frame of the present contribution oxidizing plasma pretreatment is used for the improvement of the electrocatalytic activity of graphite felt electrodes for Vanadium-Redox-Flow-Batteries (VRB. The influence of the working gas media on the catalytic activity and the surface morphology is demonstrated. The electrocatalytical properties of the graphite felt electrodes were examined by cyclic voltammetry and electrochemical impedance spectroscopy. The obtained results show that a significant improvement of the redox reaction kinetics can be achieved for all plasma modified samples using different working gasses (Ar, N2 and compressed air in an oxidizing environment. Nitrogen plasma treatment leads to the highest catalytical activities at the same operational conditions. Through a variation of the nitrogen plasma treatment duration a maximum performance at about 14 min cm-2 was observed, which is also represented by a minimum of 90 Ω in the charge transfer resistance obtained by EIS measurements. The morphology changes of the graphitized surface were followed using SEM.

  11. Gas Property Demonstrations Using Plastic Water Bottles

    Science.gov (United States)

    Campbell, Dean J.; Bannon, Stephen J.; Gunter, Molly M.

    2011-01-01

    Plastic water bottles are convenient containers for demonstrations of gas properties illustrating Boyle's law, Charles's law, and Avogadro's law. The contents of iron-based disposable hand warmer packets can be used to remove oxygen gas from the air within an unfilled plastic water bottle.

  12. Green fiber bottle: Towards a sustainable package

    DEFF Research Database (Denmark)

    Didone, Mattia; Tosello, Guido; Howard, Thomas J.

    The Green Fiber Bottle is a fully biodegradable bottle made from molded paper pulp.Its development depends on the establishment of the manufacturing technology. Impulse drying, an innovative way of drying, has the potential to improve significantly the manufacturing process of the Green Fiber...

  13. Gene expression responses of HeLa cells to chemical species generated by an atmospheric plasma flow

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, Mayo, E-mail: yokoyama@plasma.ifs.tohoku.ac.jp [Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Johkura, Kohei, E-mail: kohei@shinshu-u.ac.jp [Department of Histology and Embryology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621 (Japan); Sato, Takehiko, E-mail: sato@ifs.tohoku.ac.jp [Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2014-08-08

    Highlights: • Response of HeLa cells to a plasma-irradiated medium was revealed by DNA microarray. • Gene expression pattern was basically different from that in a H{sub 2}O{sub 2}-added medium. • Prominently up-/down-regulated genes were partly shared by the two media. • Gene ontology analysis showed both similar and different responses in the two media. • Candidate genes involved in response to ROS were detected in each medium. - Abstract: Plasma irradiation generates many factors able to affect the cellular condition, and this feature has been studied for its application in the field of medicine. We previously reported that hydrogen peroxide (H{sub 2}O{sub 2}) was the major cause of HeLa cell death among the chemical species generated by high level irradiation of a culture medium by atmospheric plasma. To assess the effect of plasma-induced factors on the response of live cells, HeLa cells were exposed to a medium irradiated by a non-lethal plasma flow level, and their gene expression was broadly analyzed by DNA microarray in comparison with that in a corresponding concentration of 51 μM H{sub 2}O{sub 2}. As a result, though the cell viability was sufficiently maintained at more than 90% in both cases, the plasma-medium had a greater impact on it than the H{sub 2}O{sub 2}-medium. Hierarchical clustering analysis revealed fundamentally different cellular responses between these two media. A larger population of genes was upregulated in the plasma-medium, whereas genes were downregulated in the H{sub 2}O{sub 2}-medium. However, a part of the genes that showed prominent differential expression was shared by them, including an immediate early gene ID2. In gene ontology analysis of upregulated genes, the plasma-medium showed more diverse ontologies than the H{sub 2}O{sub 2}-medium, whereas ontologies such as “response to stimulus” were common, and several genes corresponded to “response to reactive oxygen species.” Genes of AP-1 proteins, e.g., JUN

  14. A pilot study comparing opaque, weighted bottles with conventional, clear bottles for infant feeding.

    Science.gov (United States)

    Ventura, Alison K; Pollack Golen, Rebecca

    2015-02-01

    It is hypothesized that the visual and weight cues afforded by bottle-feeding may lead mothers to overfeed in response to the amount of liquid in the bottle. The aim of the present pilot study was to test this hypothesis by comparing mothers' sensitivity and responsiveness to infant cues and infants' intakes when mothers use opaque, weighted bottles (that remove visual and weight cues) compared to conventional, clear bottles to feed their infants. We also tested the hypothesis that mothers' pressuring feeding style would moderate the effect of bottle type. Formula-feeding dyads (N = 25) visited our laboratory on two separate days. Mothers fed their infants from a clear bottle one day and an opaque, weighted bottle on the other; bottle-order was counterbalanced across the two days. Infant intake was assessed by weighing each bottle before and after the feeding. Maternal sensitivity and responsiveness to infant cues was objectively assessed using the Nursing Child Assessment Feeding Scale. Mothers were significantly more responsive to infant cues when they used opaque compared to clear bottles (p = .04). There was also a trend for infants to consume significantly less formula when fed from opaque compared to clear bottles (p = .08). Mothers' pressuring feeding style moderated the effect of bottle type on maternal responsiveness to infant cues (p = .02) and infant intake (p = .03). Specifically, mothers who reported higher levels of pressuring feeding were significantly more responsive to their infants' cues (p = .02) and fed their infants significantly less formula when using opaque versus clear bottles (p = .01); no differences were seen for mothers who reported lower levels of pressuring feeding. This study highlights a simple, yet effective intervention for improving the bottle-feeding practices of mothers who have pressuring feeding styles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. [Plasma levels of interleukin-10 and nitric oxide in response to two different desflurane anesthesia flow rates].

    Science.gov (United States)

    Kalayci, Dilek; Dikmen, Bayazit; Kaçmaz, Murat; Taşpınar, Vildan; Ornek, Dilşen; Turan, Ozlem

    2014-01-01

    This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determine whether there is a correlation between these two variables and if different desflurane anesthesia flow rates influence nitric oxide and interleukin-10 concentrations in circulation. Forty patients between 18 and 70 years and ASA I-II physical status who were scheduled to undergo thyroidectomy were enrolled in the study. Patients were allocated into two groups to receive two different desflurane anesthesia flow rates: high flow (Group HF) and low flow (Group LF). Blood samples were drawn at the beginning (t0) and end (t1) of the operation and after 24h (t2). Plasma interleukin-10 and nitric oxide levels were measured using an enzyme-linked-immunosorbent assay and a Griess reagents kit, respectively. Hemodynamic and respiratory parameters were assessed. There was no statistically significant difference between the two groups with regard to interleukin-10 levels at the times of measurement. Interleukin-10 levels were increased equally in both groups at times t1 and t2 compared with preoperative concentrations. For both groups, nitric oxide circulating concentrations were significantly reduced at times t1 and t2 compared with preoperative concentrations. However, the nitric oxide value was lower for Group HF compared to Group LF at t2. No correlation was found between the IL-10 and nitric oxide levels. Clinical usage of two different flow anesthesia forms with desflurane may increase interleukin-10 levels both in Group HF and Group LF; nitric oxide levels circulating concentrations were significantly reduced at times t1 and t2 compared with preoperative concentrations; however, at 24h postoperatively they were higher in Group LF compared to Group HF. No correlation was detected between interleukin-10 and nitric oxide levels. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  16. Plasma levels of interleukin-10 and nitric oxide in response to two different desflurane anesthesia flow rates.

    Science.gov (United States)

    Kalaycı, Dilek; Dikmen, Bayazit; Kaçmaz, Murat; Taşpınar, Vildan; Ornek, Dilşen; Turan, Ozlem

    2014-01-01

    This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determine whether there is a correlation between these two variables and if different desflurane anesthesia flow rates influence nitric oxide and interleukin-10 concentrations in circulation. Forty patients between 18 and 70 years and ASA I-II physical status who were scheduled to undergo thyroidectomy were enrolled in the study. Patients were allocated into two groups to receive two different desflurane anesthesia flow rates: high flow (Group HF) and low flow (Group LF). Blood samples were drawn at the beginning (t0) and end (t1) of the operation and after 24h (t2). Plasma interleukin-10 and nitric oxide levels were measured using an enzyme-linked-immunosorbent assay and a Griess reagents kit, respectively. Hemodynamic and respiratory parameters were assessed. There was no statistically significant difference between the two groups with regard to interleukin-10 levels at the times of measurement. Interleukin-10 levels were increased equally in both groups at times t1 and t2 compared with preoperative concentrations. For both groups, nitric oxide circulating concentrations were significantly reduced at times t1 and t2 compared with preoperative concentrations. However, the nitric oxide value was lower for Group HF compared to Group LF at t2. No correlation was found between the IL-10 and nitric oxide levels. Clinical usage of two different flow anesthesia forms with desflurane may increase interleukin-10 levels both in Group HF and Group LF; nitric oxide levels circulating concentrations were significantly reduced at times t1 and t2 compared with preoperative concentrations; however, at 24h postoperatively they were higher in Group LF compared to Group HF. No correlation was detected between interleukin-10 and nitric oxide levels. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  17. Modeling-challenge paradigm using design of experiments for spacecraft immersed in nonstationary, between-regimes, flowing plasma

    Science.gov (United States)

    Koepke, Me; Marchand, R.

    2017-10-01

    A conducting sphere and cylinder under the conditions of nonstationary, between-regimes, flowing plasma is adopted as a test case for a modeling-challenge paradigm based on design of experiments (DOE) methodology that merges numerical simulation and testing. This model/simulation development platform facilitates a red-team/blue-team style challenge aimed at a tailored set of standard experimental conditions and measurements addressing specific questions in spacecraft-environment interactions and assessing the capability of models to describe those conditions. The goal is streamlining the Model/Simulation development process. A byproduct is an enhancement of the interrelationship between experiments in the laboratory and in space. Here, we conceptualize the advantage of the model-challenge over conventional validation in advancing whole-device modeling objectives in basic and applied plasma science.

  18. Observation of ion cyclotron range of frequencies mode conversion plasma flow drive on Alcator C-Moda)

    Science.gov (United States)

    Lin, Y.; Rice, J. E.; Wukitch, S. J.; Greenwald, M. J.; Hubbard, A. E.; Ince-Cushman, A.; Lin, L.; Marmar, E. S.; Porkolab, M.; Reinke, M. L.; Tsujii, N.; Wright, J. C.; Alcator C-Mod Team

    2009-05-01

    At modest H3e levels (n3He/ne˜8%-12%), in relatively low density D(H3e) plasmas, n¯e≤1.3×1020 m-3, heated with 50 MHz rf power at Bt0˜5.1 T, strong (up to 90 km/s) toroidal rotation (Vϕ) in the cocurrent direction has been observed by high-resolution x-ray spectroscopy on Alcator C-Mod. The change in central Vϕ scales with the applied rf power (≤30 km s-1 MW-1), and is generally at least a factor of 2 higher than the empirically determined intrinsic plasma rotation scaling. The rotation in the inner plasma (r /a≤0.3) responds to the rf power more quickly than that of the outer region (r /a≥0.7), and the rotation profile is broadly peaked for r /a≤0.5. Localized poloidal rotation (0.3≤r/a≤0.6) in the ion diamagnetic drift direction (˜2 km/s at 3 MW) is also observed, and similarly increases with rf power. Changing the toroidal phase of the antenna does not affect the rotation direction, and it only weakly affects the rotation magnitude. The mode converted ion cyclotron wave (MC ICW) has been detected by a phase contrast imaging system and the MC process is confirmed by two-dimensional full wave TORIC simulations. The simulations also show that the MC ICW is strongly damped on H3e ions in the vicinity of the MC layer, approximately on the same flux surfaces where the rf driven flow is observed. The flow shear in our experiment is marginally sufficient for plasma confinement enhancement based on the comparison of the E ×B shearing rate and gyrokinetic linear stability analysis.

  19. The effect of liquid target on a nonthermal plasma jet—imaging, electric fields, visualization of gas flow and optical emission spectroscopy

    Science.gov (United States)

    Kovačević, Vesna V.; Sretenović, Goran B.; Slikboer, Elmar; Guaitella, Olivier; Sobota, Ana; Kuraica, Milorad M.

    2018-02-01

    The article describes the complex study of the interaction of a helium plasma jet with distilled water and saline. The discharge development, spatial distribution of the excited species, electric field measurement results and the results of the Schlieren imaging are presented. The results of the experiments showed that the plasma–liquid interaction could be prolonged with the proper choice of the gas composition between the jet nozzle and the target. This depends on the gas flow and the target distance. Increased conductivity of the liquid does not affect the discharge properties significantly. An increase of the gas flow enables an extension of the plasma duration on the liquid surface up to 10 µs, but with a moderate electric field strength in the ionization wave. In contrast, there is a significant enhancement of the electric field on the liquid surface, up to 30 kV cm‑1 for low flows, but with a shorter time of the overall plasma liquid interaction. Ignition of the plasma jet induces a gas flow modification and may cause turbulences in the gas flow. A significant influence of the plasma jet causing a mixing in the liquid is also recorded and it is found that the plasma jet ignition changes the direction of the liquid circulation.

  20. Flow-Induced New Channels of Energy Exchange in Multi-Scale Plasma Dynamics – Revisiting Perturbative Hybrid Kinetic-MHD Theory

    Science.gov (United States)

    Shiraishi, Junya; Miyato, Naoaki; Matsunaga, Go

    2016-01-01

    It is found that new channels of energy exchange between macro- and microscopic dynamics exist in plasmas. They are induced by macroscopic plasma flow. This finding is based on the kinetic-magnetohydrodynamic (MHD) theory, which analyses interaction between macroscopic (MHD-scale) motion and microscopic (particle-scale) dynamics. The kinetic-MHD theory is extended to include effects of macroscopic plasma flow self-consistently. The extension is realised by generalising an energy exchange term due to wave-particle resonance, denoted by δ WK. The first extension is generalisation of the particle’s Lagrangian, and the second one stems from modification to the particle distribution function due to flow. These extensions lead to a generalised expression of δ WK, which affects the MHD stability of plasmas. PMID:27160346

  1. Flow-Induced New Channels of Energy Exchange in Multi-Scale Plasma Dynamics - Revisiting Perturbative Hybrid Kinetic-MHD Theory.

    Science.gov (United States)

    Shiraishi, Junya; Miyato, Naoaki; Matsunaga, Go

    2016-05-10

    It is found that new channels of energy exchange between macro- and microscopic dynamics exist in plasmas. They are induced by macroscopic plasma flow. This finding is based on the kinetic-magnetohydrodynamic (MHD) theory, which analyses interaction between macroscopic (MHD-scale) motion and microscopic (particle-scale) dynamics. The kinetic-MHD theory is extended to include effects of macroscopic plasma flow self-consistently. The extension is realised by generalising an energy exchange term due to wave-particle resonance, denoted by δ WK. The first extension is generalisation of the particle's Lagrangian, and the second one stems from modification to the particle distribution function due to flow. These extensions lead to a generalised expression of δ WK, which affects the MHD stability of plasmas.

  2. Finite element study of three dimensional radiative nano-plasma flow subject to Hall and ion slip currents

    Directory of Open Access Journals (Sweden)

    M. Nawaz

    Full Text Available In this article, we developed a computer code of Galerikan Finite Element method (GFEM for three dimensional flow equations of nano-plasma fluid (blood in the presence of uniform applied magnetic field when Hall and ion slip current are significant. Lorentz force is calculated through generalized Ohm’s law with Maxwell equations. A series of numerical simulations are carried out to search ηmax and algebraic equations are solved by Gauss-Seidel method with simulation tolerance 10-8. Simulated results for special case have an excellent agreement with the already published results. Velocity components and temperature of the nano-plasma (blood are influenced significantly by the inclusion of nano-particles of Copper (Cu and Silver (Ag. Heat enhancement is observed when copper and silver nonmagnetic nanoparticles are used instead of simple base fluid (conventional fluid. Radiative nature of nano-plasma in the presence of magnetic field causes a decrease in the temperature due to the transfer of heat by the electromagnetic waves. In contrast to this, due to heat dissipated by Joule heating and viscous dissipation phenomena, temperature of nano-plasmaincreases as thermal radiation parameter is increased. Thermal boundary layer thickness can be controlled by using radiative fluid instead of non-radiative fluid. Momentum boundary layer thickness can be reduced by increasing the intensity of the applied magnetic field. Temperature of plasma in the presence magnetic field is higher than the plasma in the absence of magnetic field. Keywords: Nanofluid, Grid independent study, Convergence, Error analysis, Skin friction, Joule heating, Viscous dissipation, Hall and ion currents

  3. Experimental study of nonlinear interaction of plasma flow with charged thin current sheets: 2. Hall dynamics, mass and momentum transfer

    Directory of Open Access Journals (Sweden)

    S. Savin

    2006-01-01

    Full Text Available Proceeding with the analysis of Amata et al. (2005, we suggest that the general feature for the local transport at a thin magnetopause (MP consists of the penetration of ions from the magnetosheath with gyroradius larger than the MP width, and that, in crossing it, the transverse potential difference at the thin current sheet (TCS is acquired by these ions, providing a field-particle energy exchange without parallel electric fields. It is suggested that a part of the surface charge is self-consistently produced by deflection of ions in the course of inertial drift in the non-uniform electric field at MP. Consideration of the partial moments of ions with different energies demonstrates that the protons having gyroradii of roughly the same size or larger than the MP width carry fluxes normal to MP that are about 20% of the total flow in the plasma jet under MP. This is close to the excess of the ion transverse velocity over the cross-field drift speed in the plasma flow just inside MP (Amata et al., 2005, which conforms to the contribution of the finite-gyroradius inflow across MP. A linkage through the TCS between different plasmas results from the momentum conservation of the higher-energy ions. If the finite-gyroradius penetration occurs along the MP over ~1.5 RE from the observation site, then it can completely account for the formation of the jet under the MP. To provide the downstream acceleration of the flow near the MP via the cross-field drift, the weak magnetic field is suggested to rotate from its nearly parallel direction to the unperturbed flow toward being almost perpendicular to the accelerated flow near the MP. We discuss a deceleration of the higher-energy ions in the MP normal direction due to the interaction with finite-scale electric field bursts in the magnetosheath flow frame, equivalent to collisions, providing a charge separation. These effective collisions, with a nonlinear frequency proxy of the order of the proton

  4. Production and elliptic flow of dileptons and photons in a matrix model of the quark-gluon plasma.

    Science.gov (United States)

    Gale, Charles; Hidaka, Yoshimasa; Jeon, Sangyong; Lin, Shu; Paquet, Jean-François; Pisarski, Robert D; Satow, Daisuke; Skokov, Vladimir V; Vujanovic, Gojko

    2015-02-20

    We consider a nonperturbative approach to the thermal production of dileptons and photons at temperatures near the critical temperature in QCD. The suppression of colored excitations at low temperature is modeled by including a small value of the Polyakov loop, in a "semi"-quark-gluon plasma (QGP). Comparing the semi-QGP to the perturbative QGP, we find a mild enhancement of thermal dileptons. In contrast, to leading logarithmic order in weak coupling there are far fewer hard photons from the semi-QGP than the usual QGP. To illustrate the possible effects on photon and dilepton production in heavy-ion collisions, we integrate the rate with a simulation using ideal hydrodynamics. Dileptons uniformly exhibit a small flow, but the strong suppression of photons in the semi-QGP tends to weight the elliptical flow of photons to that generated in the hadronic phase.

  5. Particle Morphology Effects on Flow Characteristics of PS304 Plasma Spray Coating Feedstock Powder Blend

    Science.gov (United States)

    Stanford, Malcolm K.; DellaCorte, Christopher; Eylon, Daniel

    2002-01-01

    The effects of BaF2-CaF 2 particle morphology on PS304 feedstock powder flow ability have been investigated. BaF2-CaF2 eutectic powders were fabricated by comminution (angular) and by gas atomization (spherical). The fluoride powders were added incrementally to the other powder constituents of the PS304 feedstock: nichrome, chromia, and silver powders. A linear relationship between flow time and concentration of BaF2-CaF2 powder was found. Flow of the powder blend with spherical BaF2-CaF2 was better than the angular BaF2-CaF2. Flow ability of the powder blend with angular fluorides decreased linearly with increasing fluoride concentration. Flow of the powder blend with spherical fluorides was independent of fluoride concentration. Results suggest that for this material blend, particle morphology plays a significant role in powder blend flow behavior, offering potential methods to improve powder flow ability and enhance the commercial potential. These findings may have applicability to other difficult-to-flow powders such as cohesive ceramics.

  6. Effects of Humidity On the Flow Characteristics of PS304 Plasma Spray Feedstock Powder Blend

    Science.gov (United States)

    Stanford, Malcolm K.; DellaCorte, Christopher

    2002-01-01

    The effects of environmental humidity on the flow characteristics of PS304 feedstock have been investigated. Angular and spherical BaF2-CaF2 powder was fabricated by comminution and by atomization, respectively. The fluorides were added incrementally to the nichrome, chromia, and silver powders to produce PS304 feedstock. The powders were dried in a vacuum oven and cooled to a Tom temperature under dry nitrogen. The flow of the powder was studied from 2 to 100 percent relative humidity (RH) The results suggest that the feedstock flow is slightly degraded with increasing humidity below 66 percent RH and is more affected above 66 percent RH. There was no flow above 88 percent RH. Narrower particle size distributions of the angular fluorides allowed flow up to 95 percent RH. These results offer guidance that enhances the commercial potential for this material system.

  7. Suitability of Broken Bottles as Fine Aggregate for Production of ...

    African Journals Online (AJOL)

    The use of broken bottles as partial replacement of river sand for production of concrete was investigated. The grading of the broken bottles and sand fell in zone II. The specific gravity of the bottles was 2.55 and that of sand was 2.65. Sand was replaced with the broken bottles in the proportions of 0%, 10%, 20%, 30%, 40%, ...

  8. 27 CFR 24.308 - Bottled or packed wine record.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bottled or packed wine... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.308 Bottled or packed wine record. A proprietor who bottles, packs, or receives bottled or packed beverage wine in bond shall...

  9. 27 CFR 24.256 - Bottle aging wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bottle aging wine. 24.256... OF THE TREASURY LIQUORS WINE Storage, Treatment and Finishing of Wine Bottling, Packing, and Labeling of Wine § 24.256 Bottle aging wine. Wine bottled or packed and stored for the purpose of aging need...

  10. Self-generated zonal flows in the plasma turbulence driven by trapped-ion and trapped-electron instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Drouot, T.; Gravier, E.; Reveille, T.; Collard, M. [Institut Jean Lamour, UMR 7198 CNRS - Université de Lorraine, 54 506 Vandoeuvre-lès-Nancy Cedex (France)

    2015-10-15

    This paper presents a study of zonal flows generated by trapped-electron mode and trapped-ion mode micro turbulence as a function of two plasma parameters—banana width and electron temperature. For this purpose, a gyrokinetic code considering only trapped particles is used. First, an analytical equation giving the predicted level of zonal flows is derived from the quasi-neutrality equation of our model, as a function of the density fluctuation levels and the banana widths. Then, the influence of the banana width on the number of zonal flows occurring in the system is studied using the gyrokinetic code. Finally, the impact of the temperature ratio T{sub e}/T{sub i} on the reduction of zonal flows is shown and a close link is highlighted between reduction and different gyro-and-bounce-average ion and electron density fluctuation levels. This reduction is found to be due to the amplitudes of gyro-and-bounce-average density perturbations n{sub e} and n{sub i} gradually becoming closer, which is in agreement with the analytical results given by the quasi-neutrality equation.

  11. Silicon oxide permeation barrier coating of PET bottles and foils

    Science.gov (United States)

    Steves, Simon; Deilmann, Michael; Awakowicz, Peter

    2009-10-01

    Modern packaging materials such as polyethylene terephthalate (PET) have displaced established materials in many areas of food and beverage packaging. Plastic packing materials offer are various advantages concerning production and handling. PET bottles for instance are non-breakable and lightweight compared to glass and metal containers. However, PET offers poor barrier properties against gas permeation. Therefore, the shelf live of packaged food is reduced. Permeation of gases can be reduced by depositing transparent plasma polymerized silicon oxide (SiOx) barrier coatings. A microwave (2.45 GHz) driven low pressure plasma reactor is developed based on a modified Plasmaline antenna to treat PET foils or bottles. To increase the barrier properties of the coatings furthermore a RF substrate bias (13.56 MHz) is applied. The composition of the coatings is analyzed by means of Fourier transform infrared (FTIR) spectroscopy regarding carbon and hydrogen content. Influence of gas phase composition and substrate bias on chemical composition of the coatings is discussed. A strong relation between barrier properties and film composition is found: good oxygen barriers are observed as carbon content is reduced and films become quartz-like. Regarding oxygen permeation a barrier improvement factor (BIF) of 70 is achieved.

  12. Free-flow electrophoresis of plasma membrane vesicles enriched by two-phase partitioning enhances the quality of the proteome from Arabidopsis seedlings

    DEFF Research Database (Denmark)

    de Michele, Roberto; McFarlane, Heather E; Parsons, Harriet Tempé

    2016-01-01

    The plant plasma membrane is the interface between the cell and its environment undertaking a range of important functions related to transport, signaling, cell wall biosynthesis, and secretion. Multiple proteomic studies have attempted to capture the diversity of proteins in the plasma membrane...... using biochemical fractionation techniques. In this study, two-phase partitioning was combined with free-flow electrophoresis to produce a population of highly purified plasma membrane vesicles that were subsequently characterized by tandem mass spectroscopy. This combined high-quality plasma membrane...... isolation technique produced a reproducible proteomic library of over 1000 proteins with an extended dynamic range including plasma membrane-associated proteins. The approach enabled the detection of a number of putative plasma membrane proteins not previously identified by other studies, including...

  13. Nature of Transport across Sheared Zonal Flows in Electrostatic Ion-Temperature-Gradient Gyrokinetic Plasma Turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Raul [ORNL; Newman, David E [University of Alaska; Leboeuf, Jean-Noel [JNL Scientific, Inc., Casa Grande, AZ; Decyk, Viktor [University of California, Los Angeles; Carreras, Benjamin A [BACV Solutions, Inc., Oak Ridge

    2008-01-01

    It is shown that the usual picture for the suppression of turbulent transport across a stable sheared flow based on a reduction of diffusive transport coefficients is, by itself, incomplete. By means of toroidal gyrokinetic simulations of electrostatic, collisionless ion-temperature-gradient turbulence, it is found that the nature of the transport is altered fundamentally, changing from diffusive to anticorrelated and subdiffusive. Additionally, whenever the flows are self-consistently driven by turbulence, the transport gains an additional non-Gaussian character. These results suggest that a description of transport across sheared flows using effective diffusivities is oversimplified.

  14. Flow shear stabilization of rotating plasmas due to the Coriolis effect

    NARCIS (Netherlands)

    J.W. Haverkort (Willem); H.J. de Blank

    2012-01-01

    htmlabstractA radially decreasing toroidal rotation frequency can have a stabilizing effect on nonaxisymmetric magnetohydrodynamic (MHD) instabilities. We show that this is a consequence of the Coriolis effect that induces a restoring pressure gradient force when plasma is perturbed radially. In a

  15. Flow shear stabilization of rotating plasmas due to the Coriolis effect

    NARCIS (Netherlands)

    Haverkort, J. W.; de Blank, H. J.

    2012-01-01

    A radially decreasing toroidal rotation frequency can have a stabilizing effect on nonaxisymmetric magnetohydrodynamic (MHD) instabilities. We show that this is a consequence of the Coriolis effect that induces a restoring pressure gradient force when plasma is perturbed radially. In a rotating

  16. Influence of external 3D magnetic fields on helical equilibrium and plasma flow in RFX-mod

    Energy Technology Data Exchange (ETDEWEB)

    Piovesan, P; Bonfiglio, D; Bonomo, F; Cappello, S; Carraro, L; Cavazzana, R; Gobbin, M; Marrelli, L; Martin, P; Martines, E; Momo, B; Piron, L; Puiatti, M E; Soppelsa, A; Valisa, M; Zanca, P; Zaniol, B [Consorzio RFX, EURATOM-ENEA Association, Corso Stati Uniti 4, 35127 Padova (Italy)

    2011-08-15

    A spontaneous transition to a helical equilibrium with an electron internal transport barrier is observed in RFX-mod as the plasma current is raised above 1 MA (Lorenzini R et al 2009 Nature Phys. 5 570). The helical magnetic equilibrium can be controlled with external three-dimensional (3D) magnetic fields applied by 192 active coils, providing proper helical boundary conditions either rotating or static. The persistence of the helical equilibrium is strongly increased in this way. A slight reduction in the energy confinement time of about 15% is observed, likely due to the increased plasma-wall interaction associated with the finite radial magnetic field imposed at the edge. A global helical flow develops in these states and is expected to play a role in the helical self-organization. In particular, its shear may contribute to the ITB formation and is observed to increase with the externally applied radial field. The possible origins of this flow, from nonlinear visco-resistive magnetohydrodynamic (MHD) and/or ambipolar electric fields, will be discussed.

  17. The structure of bow shocks formed by the interaction of pulsed-power driven magnetised plasma flows with conducting obstacles

    Science.gov (United States)

    Burdiak, G. C.; Lebedev, S. V.; Bland, S. N.; Clayson, T.; Hare, J.; Suttle, L.; Suzuki-Vidal, F.; Garcia, D. C.; Chittenden, J. P.; Bott-Suzuki, S.; Ciardi, A.; Frank, A.; Lane, T. S.

    2017-07-01

    We present an experimental study of the development and structure of bow shocks produced by the interaction of a magnetised, collisional, super-Alfvénic plasma flow with conducting cylindrical obstacles. The plasma flow with an embedded, frozen-in magnetic field (ReM ˜ 20) is produced by the current-driven ablation of fine aluminium wires in an inverse, exploding wire array z-pinch. We show that the orientation of the embedded field with respect to the obstacles has a dramatic effect on the bow shock structure. When the field is aligned with the obstacle, a sharp bow shock is formed with a global structure that is determined simply by the fast magneto-sonic Mach number. When the field is orthogonal to the obstacle, magnetic draping occurs. This leads to the growth of a magnetic precursor and the subsequent development of a magnetised bow shock that is mediated by two-fluid effects, with an opening angle and a stand-off distance, that are both many times larger than in the parallel geometry. By changing the field orientation, we change the fluid regime and physical mechanisms that are responsible for the development of the bow shocks. MHD simulations show good agreement with the structure of well-developed bow shocks. However, collisionless, two-fluid effects will need to be included within models to accurately reproduce the development of the shock with an orthogonal B-field.

  18. Ultra-low Flow Liquid Chromatography Assay with Ultraviolet (UV) Detection for Piperine Quantitation in Human Plasma

    Science.gov (United States)

    Kakarala, Madhuri; Dubey, Shiv Kumar; Tarnowski, Malloree; Cheng, Connie; Liyanage, Samadhi; Strawder, Terrence; Tazi, Karim; Sen, Ananda; Djuric, Zora; Brenner, Dean E.

    2015-01-01

    A robust and sensitive ultra-low flow liquid chromatography (UFLC) method that can reproducibly, at reasonable cost, detect low concentrations of piperine from human plasma is necessary. Piperine in plasma was separated and quantified by a gradient method using ultraviolet detection at a maximal absorbance wavelength of 340 nm. An aliquot was injected onto a reversed-phase column Waters SymmetryShield, 2.1 × 100 mm, 3.5 μm, C18 column, attached to a Waters absorbosphere, 4.6 × 30 mm, C18 guard column and eluted with a mobile phase containing a mixture of acetonitrile/water/ acetic acid (25:74.9:0.1, v/v/v) on line A and acetonitrile/acetic acid (99.9:0.1, v/v) on line B. The flow rate was 0.3 mL/min. The gradient method consisted of an opening condition of 20% pump B, with a linear increase to 37% pump B over 8 min, then a linear increase to 100% pump B at 11 min, 2 min at 100% pump B, and then a return to the opening condition (20% pump B) via a linear gradient over 2 min, followed by 5 min re-equilibration at opening conditions. The total run time was 20 min for each sample. All samples were processed protected from ambient light to avoid isomerization of piperine. The plasma assay was linear with R = 0.9995, with a lower limit of detection [signal-to-noise (S/N) > 5:1] of 100 pg of piperine loaded into the analytical system with acceptable accuracy and precision. Extraction recoveries of piperine from human plasma were 88% for quality control high (QCH), 93% for quality control medium (QCM), and 90% for quality control low (QCL), and the matrix effect was Piperine was quantifiable from a 50 mg oral dose given to human volunteers. A UFLC method for the rapid assay of human plasma with sensitivity to detect as low as 5 ng/mL piperine was developed. The method sensitivity equals that of liquid chromatography/tandem mass spectrometry (LC/MSMS) methods with much less cost. PMID:20465211

  19. Helmholtz Resonance in a Water Bottle

    Directory of Open Access Journals (Sweden)

    Annirudh Balachandran

    2011-01-01

    Full Text Available The resonance that occurs when blowing across the top of a water bottle filled with different volumes of water was studied. It was shown that, contrary to popular belief, a water bottle is not an ideal Helmholtz resonator. Resonance in a water bottle with an extendable neck was then studied to determine how the length of the neck affects the resonance. The results showed that ideal Helmholtz resonance occurs when the neck length was in a middle range, while for no neck a standing wave resonance occurs. For a very long neck the results were inconclusive.

  20. Dynamic Stall Flow Control Through the Use of a Novel Plasma Based Actuator Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Lynntech proposes a novel flow control methodology for airfoils undergoing dynamic stall. Dynamic stall refers to an aerodynamic phenomenon that is experienced by...

  1. The impact of plasma induced flow on the boundary layer in a narrow channel

    Directory of Open Access Journals (Sweden)

    Procházka P.

    2015-01-01

    Full Text Available The induced flow generated by dielectric barrier discharge (DBD actuator working in steady and unsteady regime will be used to modify properties of naturally developed boundary layer (BL in short and long rectangular perspex channel which is connected to the blow-down wind tunnel. The actuator is placed in spanwise configuration and the inlet velocities will range between 5 and 20 m•s-1. Previously, mean flow field and statistical quantities were subjugated to investigation. In this paper, there will be presented dynamical features of the BL. Oscillation pattern decomposition (OPD of influenced flow field and frequency analysis will be presented. These results should be taken into account regarding to use in the flow around a bluff body.

  2. Momentum transfer and flow induction in a dielectric barrier discharge plasma actuator

    National Research Council Canada - National Science Library

    Abe, T; Takagaki, M; Yamada, K

    2012-01-01

    .... The induced flow originated from the vicinity of an exposed electrode edge, and similar to a wall jet, it smoothly spread over the surface until a vortex was generated at the tip of the wall jet...

  3. Flowing liquid lithium plasma-facing components – Physics, technology and system analysis of the LiMIT system

    Directory of Open Access Journals (Sweden)

    D.N. Ruzic

    2017-08-01

    Full Text Available The use of low atomic number liquid metals has been shown to have the potential to solve many of the prevalent problems like erosion and radiation losses associated with the interaction of fusion plasma with the plasma facing component (PFC structures in tokamaks. Since the first evidence of lithium increasing plasma performance in TFTR [1], the benefits of using lithium in fusion environments have been seen in many devices, including CDX-U [2], NSTX [3], LTX [4], and DIII-D [5]. While both fast flow and slow flow concepts have been studied with regards to liquid lithium first wall alternatives, this report will focus on efforts placed on fast flow research and will mainly focus on advancements in the LiMIT device that help to eliminate concerns over the broad use of liquid lithium. Due to the promising TFTR results along with results obtained at the University of Illinois at Urbana-Champaign [6], suitably designed trench structures holding liquid lithium could be an appropriate fast flow candidate for PFC modules in future fusion devices. There are four potential shortcomings of this approach: (1 Droplet ejection, (2 Wetting control, (3 Tritium retention, and (4 Limited heat flux handling. Droplet ejection is discussed in a companion publication [7], while this paper addresses the topics of wetting control and heat flux handling. Limitations in wetting and prevention of lithium creep (i.e. getting and keeping the lithium only where it should be have been solved by laser-texturing the base material with extreme short laser pulses (pico – femto second of high power (several 10s of W. Micro- and nano-structuring results indicate that the textured substrates displayed significant change in their wetting properties, increasing the temperature needed to wet from 310 °C to 390 °C. Lastly, initial designs for the Lithium Metal Infused Trenches (LiMIT [6] showed dryout above 3 MW/m2, but new designs of the trench shaping show potential to be

  4. Effects of Input Voltage on Flow Separation Control for Low-Pressure Turbine at Low Reynolds Number by Plasma Actuators

    Directory of Open Access Journals (Sweden)

    Takayuki Matsunuma

    2012-01-01

    Full Text Available Active flow control using dielectric barrier discharge (DBD plasma actuators was investigated to reattach the simulated boundary layer separation on the suction surface of a turbine blade at low Reynolds number, Re = 1.7 × 104. The flow separation is induced on a curved plate installed in the test section of a low-speed wind tunnel. Particle image velocimetry (PIV was used to obtain instantaneous and time-averaged two-dimensional velocity measurements. The amplitude of input voltage for the plasma actuator was varied from ±2.0 kV to ±2.8 kV. The separated flow reattached on the curved wall when the input voltage was ±2.4 kV and above. The displacement thickness of the boundary layer near the trailing edge decreased by 20% at ±2.0 kV. The displacement thickness was suddenly reduced as much as 56% at ±2.2 kV, and it was reduced gradually from ±2.4 kV to ±2.8 kV (77% reduction. The total pressure loss coefficient, estimated from the boundary layer displacement thickness and momentum thickness, was 0.172 at the baseline (actuator off condition. The total pressure loss was reduced to 0.107 (38% reduction at ±2.2 kV and 0.078 (55% reduction at ±2.8 kV.

  5. Characterization of Carbon Particulates in the Exit Flow of a Plasma Pyrolysis Assembly (PPA) Reactor

    Science.gov (United States)

    Green, Robert D.; Meyer, Marit E.; Agui, Juan H.; Berger, Gordon M.; Vijayakumar, R.; Abney, Morgan B.; Greenwood, Zachary

    2015-01-01

    The ISS presently recovers oxygen from crew respiration via a Carbon Dioxide Reduction Assembly (CRA) that utilizes the Sabatier chemical process to reduce captured carbon dioxide to methane (CH4) and water. In order to recover more of the hydrogen from the methane and increase oxygen recovery, NASA Marshall Space Flight Center (MSFC) is investigating a technology, plasma pyrolysis, to convert the methane to acetylene. The Plasma Pyrolysis Assembly (or PPA), achieves 90% or greater conversion efficiency, but a small amount of solid carbon particulates are generated as a side product and must be filtered before the acetylene is removed and the hydrogen-rich gas stream is recycled back to the CRA. In this work, we present the experimental results of an initial characterization of the carbon particulates in the PPA exit gas stream. We also present several potential options to remove these carbon particulates via carbon traps and filters to minimize resupply mass and required downtime for regeneration.

  6. Shear flow effect on ion temperature gradient vortices in plasmas with sheared magnetic field

    DEFF Research Database (Denmark)

    Chakrabarti, N.; Juul Rasmussen, J.

    1999-01-01

    The effect of velocity shear on ion temperature gradient (ITG) driven vortices in a nonuniform plasma in a curved, sheared magnetic field is investigated. In absence of parallel ion dynamics, vortex solutions for the ITG mode are studied analytically. It is shown that under certain conditions...... and ultimately lead to a dominating monopolar form. The effects of magnetic shear indicate it may destroy these structures. (C) 1999 American Institute of Physics....

  7. 2-D Hybrid Model to Study Flow Curvature Effect on Low Frequency Plasma Turbulence

    Science.gov (United States)

    Sen, S.; Lin, D.; Scales, W.; Goldstein, M.

    2017-10-01

    In this study of flow curvature effects, a two-dimensional hybrid model is used to simulate the Kelvin-Helmholtz instability (KHI). The hybrid model treats the ions as particles, and electrons as massless fluid. Pressure and resistivity are assumed as isotropic. A classical configuration for the study of KHI is investigated, i.e. transverse shear flow to uniform background magnetic field. This is thought as the most unstable situation in magnetohydrodynamic (MHD) theory. There are 50 super particles per cell in the current simulations, which number could be increased to as much as 200 in the future. The boundary is periodic along the flow direction and reflective in the perpendicular direction. The code was originally developed by the Los Alamos National Laboratory and has been successfully applied to the study of Kelvin-Helmholtz instability on the Earth's magnetopause. In this study, the code has been running on the Advanced Research Computing (ARC) platforms of Virginia Tech. Four distinct shear profiles are simulated to investigate the effects of flow curvature on the growth of the KH instability: uniform flow, linear shear without curvature, quadratic profile with positive curvature, and quadratic profile with negative curvature. This work is supported by the DOE Grant DE-SC0016397.

  8. Particle Size Effects on Flow Properties of PS304 Plasma Spray Feedstock Powder Blend

    Science.gov (United States)

    Stanford, Malcolm K.; DellaCorte, Christopher; Eylon, Daniel

    2002-01-01

    The effects of BaF2-CaF2 particle size and size distribution on PS304 feedstock powder flowability have been investigated. Angular BaF2-CaF2 eutectic powders were produced by comminution and classified by screening to obtain 38 to 45 microns 45 to 106 microns, 63 to 106 microns, 45 to 53 microns, 63 to 75 microns, and 90 to 106 microns particle size distributions. The fluorides were added incrementally from 0 to 10 wt% to the other powder constituents of the PS304 feedstock: nichrome, chromia, and silver powders. The flow rate of the powder blends decreased linearly with increasing concentration of the fluorides. Flow was degraded with decreasing BaF2-CaF2 particle size and with increasing BaF2-CaF2 particle size distribution. A semiempirical relationship is offered to describe the PS304 powder blend flow behavior. The Hausner Ratio confirmed the funnel flow test results, but was slightly less sensitive to differences in BaF2-CaF2 particle size and size distribution. These findings may have applicability to other powders that do not flow easily, such as ceramic powders.

  9. Novel Gas Barrier SiOC Coating to PET Bottles through a Hot Wire CVD Method

    Directory of Open Access Journals (Sweden)

    Masaki Nakaya

    2016-01-01

    Full Text Available In an attempt to enhance the gas barrier enhancement of plastic containers such as poly(ethylene terephthalate bottles, a novel method was found using a hot wire CVD technique, where tantalum wire is heated and exposed to a gas flow of vinyl silane. The resultant SiOC thin film was confirmed to characteristically contain Si-Si bonds in its surface and demonstrate a remarkably and highly practical decrease of the permeation of various gas through poly(ethylene terephthalate bottles.

  10. Bottle appeal drifts across the Pacific

    Science.gov (United States)

    Ebbesmeyer, Curtis; Ingraham, W. James, Jr.; McKinnon, Richard; Okubo, Akira; Wang, Dong-Ping; Strickland, Richard; Willing, Peter

    Pacific drift currents were used by a group of oceanographers to estimate the path of a drift bottle that was found on a beach of Barkley Sound in Vancouver Island by Richard Strickland on June 10, 1990. The Chinese rice wine bottle, which remained unopened until December 18, 1991, contained six leaflets, one appealing for the release of China's well-known dissident, Wei Jingsheng. The bottle was one of thousands set adrift as part of a propaganda effort from the islands of Quemoy and Matsu off mainland China shortly after Wei was sentenced in 1979 to 15 years in prison (see Figure 1 for locations). Wei was in poor health and still in prison when the bottle made its way across the Pacific Ocean.

  11. GLOBEC NEP Rosette Bottle Data (2002)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GLOBEC (GLOBal Ocean ECosystems Dynamics) NEP (Northeast Pacific) Rosette Bottle Data from New Horizon Cruise (NH0207: 1-19 August 2002). Notes: Physical data...

  12. Numerical simulation and sensitivity analysis of a low-Reynolds-number flow around a square cylinder controlled using plasma actuators

    Science.gov (United States)

    Anzai, Yosuke; Fukagata, Koji; Meliga, Philippe; Boujo, Edouard; Gallaire, François

    2017-04-01

    Flow around a square cylinder controlled using plasma actuators (PAs) is numerically investigated by direct numerical simulation in order to clarify the most effective location of actuator installation and to elucidate the mechanism of control effect. The Reynolds number based on the cylinder diameter and the free-stream velocity is set to be 100 to study the fundamental effect of PAs on two-dimensional vortex shedding, and three different locations of PAs are considered. The mean drag and the root-mean-square of lift fluctuations are found to be reduced by 51% and 99% in the case where two opposing PAs are aligned vertically on the rear surface. In that case, a jet flow similar to a base jet is generated by the collision of the streaming flows induced by the two opposing PAs, and the vortex shedding is completely suppressed. The simulation results are ultimately revisited in the frame of linear sensitivity analysis, whose computational cost is much lower than that of performing the full simulation. A good agreement is reported for low control amplitudes, which allows further discussion of the linear optimal arrangement for any number of PAs.

  13. Steady state drift vortices in plasmas with shear flow in equilibrium

    DEFF Research Database (Denmark)

    Chakrabarti, N.

    1999-01-01

    The Hasegawa-Mima equation in the presence of sheared poloidal flow is solved for two-dimensional steady state vortex. It is shown that when the phase velocity of the vortex is the same as the diamagnetic drift velocity, an exact solution in the form of counter-rotating vortices may appear...

  14. A flow cytometric method for characterization of circulating cell-derived microparticles in plasma

    DEFF Research Database (Denmark)

    Nielsen, Morten Hjuler; Beck-Nielsen, Henning; Andersen, Morten Nørgaard

    2014-01-01

    BACKGROUND AND AIM: Previous studies on circulating microparticles (MPs) indicate that the majority of MPs are of a size below the detection limit of most standard flow cytometers. The objective of the present study was to establish a method to analyze MP subpopulations above the threshold of det...

  15. Flow induced dispersion analysis rapidly quantifies proteins in human plasma samples

    DEFF Research Database (Denmark)

    Poulsen, Nicklas N; Andersen, Nina Z; Østergaard, Jesper

    2015-01-01

    to cumbersome and expensive assay development. In this work a new approach for quantification based on changes in diffusivity is presented. The apparent diffusivity of an indicator molecule interacting with the protein of interest is determined by Taylor Dispersion Analysis (TDA) in a hydrodynamic flow system...

  16. Development of core ion temperature gradients and edge sheared flows in a helicon plasma device investigated by laser induced fluorescence measurements

    Science.gov (United States)

    Thakur, S. C.; Gosselin, J. J.; McKee, J.; Scime, E. E.; Sears, S. H.; Tynan, G. R.

    2016-08-01

    We report experimental observation of ion heating and subsequent development of a prominent ion temperature gradient in the core of a linear magnetized plasma device, and the controlled shear de-correlation experiment. Simultaneously, we also observe the development of strong sheared flows at the edge of the device. Both the ion temperature and the azimuthal velocity profiles are quite flat at low magnetic fields. As the magnetic field is increased, the core ion temperature increases, producing centrally peaked ion temperature profiles and therefore strong radial gradients in the ion temperature. Similarly, we observe the development of large azimuthal flows at the edge, with increasing magnetic field, leading to strong radially sheared plasma flows. The ion velocities and temperatures are derived from laser induced fluorescence measurements of Doppler resolved velocity distribution functions of argon ions. These features are consistent with the previous observations of simultaneously existing radially separated multiple plasma instabilities that exhibit complex plasma dynamics in a very simple plasma system. The ion temperature gradients in the core and the radially sheared azimuthal velocities at the edge point to mechanisms that can drive the multiple plasma instabilities, that were reported earlier.

  17. Observations of High-Speed Plasma Flow Near the Earth’s Magnetopause: Evidence for Reconnection.

    Science.gov (United States)

    1981-06-01

    km/s an-1 -333 km/s, resnectivoly, with f low nitch -anolf- noir 164. In this same combined hulk plasma frame, the low-enermY !I+ component has a...results in significantly decreased energetic ion responses in the dawnward-lookinq sectors. Energetic ions with 0-qnO nitch - angles are nearly absent in...inq i’,, i (ns ,Ot of in , ihrw i , nancak,-shapod nitch - n,l, di;t rihf iof n; thi!; prc.s .,I:, f 22 higher energy ions (> 45 key) more than ions

  18. Chemical mechanisms inducing a dc current measured in the flowing post-discharge of an RF He-O2 plasma torch

    CERN Document Server

    Dufour, Thierry; Vandencasteele, N; Reniers, F

    2016-01-01

    The post-discharge of an RF plasma torch supplied with helium and oxygen gases is characterized by mass spectrometry, optical emission spectroscopy and electrical measurements. We have proved the existence of a dc current in the post-discharge (1--20 A), attributed to the Penning ionization of atmospheric nitrogen and oxygenated species. The mechanisms ruling this dc current are investigated through experiments in which we discuss the influence of the O2 flow rate, the He flow rate and the distance separating the plasma torch from a material surface located downstream.

  19. A limited plasma cell flow cytometry panel with reflex CD138 immunohistochemistry is an optimal workflow process for evaluating plasma cell neoplasms in bone marrow specimens.

    Science.gov (United States)

    Chen, Zhongchuan Will; Perkins, Sherrie L; Weiss, Ronald L; Bahler, David W; Hussong, Jerry W; Salama, Mohamed E

    2015-01-01

    To determine the optimal workflow combination of flow cytometry (FC) and immunohistochemistry tests for efficient and cost-effective evaluation of plasma cell (PC) neoplasms (PCNs) in bone marrow (BM) specimens. Various workflow combinations of immunohistochemistry and FC for 4,031 BM specimens worked up for PCNs were compared. Turnaround time (TAT), immunohistochemistry usage, technical charges, and addendum/amendment rates were compared between periods to determine the optimal workflow combination. Five distinct workflow periods were identified, with varying combinations of full or limited FC panels for assessing PC clonality and CD138/κ/λ immunohistochemistry for PC quantification. Replacement of full FC with limited FC was associated with significant reductions in TAT and number of immunostains performed per case. Elimination of immunohistochemistry on cases determined to be polyclonal by FC also resulted in significant reductions in immunohistochemistry usage and significant cost savings. Assessment of PC clonality using a limited FC panel followed by reflex CD138 immunohistochemistry on cases that are monoclonal by FC provides an optimal and cost-effective workflow for evaluating PCNs in BM samples. Copyright© by the American Society for Clinical Pathology.

  20. Field-aligned currents and magnetospheric generator in experiments on a laser-produced plasma flowing around a magnetic dipole

    Science.gov (United States)

    Shaikhislamov, I. F.; Antonov, V. M.; Zakharov, Yu. P.; Boyarintsev, E. L.; Melekhov, A. V.; Posukh, V. G.; Ponomarenko, A. G.

    2014-07-01

    A laboratory experiment on modeling the magnetospheric generator of the field-aligned currents and the Earth's transpolar potential in the absence of IMF is illustrated. The measurements of the total field-aligned current in the generator shorted mode and the transpolar potential in the circuit disconnection mode made it possible to determine the generator internal resistance. A model that explains the saturation current and internal resistance by the feedback between the field-aligned current and plasma flank motions has been proposed. This feedback is described through the effective resistance, which is proportional to the flow rate and the ratio of the boundary layer to the dimension of the magnetosphere. For the experimental conditions, the calculated generator resistance was in good agreement with the measured value. The estimates for the Earth's magnetosphere indicate that the MHD generator internal resistance in the boundary layer is usually much lower than the reverse integral conductivity of the ionosphere.

  1. Extension of the flow-rate-of-strain tensor formulation of plasma rotation theory to non-axisymmetric tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Stacey, W. M. [Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Bae, C. [National Fusion Research Institute, Daejoen (Korea, Republic of)

    2015-06-15

    A systematic formalism for the calculation of rotation in non-axisymmetric tokamaks with 3D magnetic fields is described. The Braginskii Ωτ-ordered viscous stress tensor formalism, generalized to accommodate non-axisymmetric 3D magnetic fields in general toroidal flux surface geometry, and the resulting fluid moment equations provide a systematic formalism for the calculation of toroidal and poloidal rotation and radial ion flow in tokamaks in the presence of various non-axisymmetric “neoclassical toroidal viscosity” mechanisms. The relation among rotation velocities, radial ion particle flux, ion orbit loss, and radial electric field is discussed, and the possibility of controlling these quantities by producing externally controllable toroidal and/or poloidal currents in the edge plasma for this purpose is suggested for future investigation.

  2. Influence of SDBD plasma aerodynamic actuation on flow control by AC power supply and AC-DC power supply

    Science.gov (United States)

    Hu, Xu; Gao, Chao; Hao, Jiangnan

    2018-01-01

    In this paper, the excitation effect of single dielectric barrier discharge plasma actuator (SDBD) is compared by using AC power supply and AC-DC power supply. AC-DC power supply is based on the AC power supply, just adding DC component. The flow measurement is carried out by PIV technique. Results show that the excitation effect of AC power supply and AC-DC power supply increases by the increase of voltage, the range of speed field excited by AC power is greater than that of AC-DC power supply. For x direction maximum speed, excited by AC power supply is close to AC-DC, and for y direction maximum speed, AC power supply is greater than AC-DC power supply. So the excitation effect of AC power supply is better than that of AC-DC power supply for SDBD.

  3. Synthesis of silicon carbide nanopowders in free flowing plasma jet with different energy levels

    Science.gov (United States)

    Nikitin, D.; Sivkov, A.; Rahmatullin, I.; Ivashutenko, A.

    2017-05-01

    Silicon carbide (SiC) nanopowders were produced by the synthesis in an electrodischarge plasma jet generated by a high-current pulsed coaxial magnetoplasma accelerator. The present work focuses on the experiments where the obtained hypersonic plasma jet flew into space of the reactor chamber without impact on a target. The energy level of experiments was changed from ∼10.0 to ∼30.0 kJ. Four experiments were carried out at different energy levels. The powder products synthesized by the plasmadynamic method were studied by such well-known methods: X-ray diffraction (XRD), transmission electron microscopy (TEM). All the powders mainly contain cubic silicon carbide (β-SiC) particles with clear crystal structures and triangular shapes. SiC content reaches its maximum value 95% at the energy level 21.0 kJ, then SiC content is decreased to 70% the energy level 27.8 kJ. The powder crystallites in different experiments have approximately the same average crystallite size because quasistationary time, which allows growing powder crystallites, is absent.

  4. Parametric Investigation of Nanosecond Pulse Driven Dielectric Barrier Discharge Plasma Actuators for Aerodynamic Flow Control

    Science.gov (United States)

    Dawson, Robert; Little, Jesse

    2012-11-01

    Nanosecond pulse driven dielectric barrier discharge plasma actuators are studied experimentally in quiescent atmosphere. Per unit length peak energy and instantaneous peak power are calculated using simultaneous voltage and current measurements. Electrical characteristics are evaluated as a function of peak voltage, pulse frequency, discharge length and dielectric thickness. Schlieren imaging of compression waves is used to provide a relative measure of discharge energy that is coupled to the near surface gas as heat for the same parameters. Characteristics of the DBD load have a substantial effect on voltage and current traces which are reflected in the peak energy and peak power. Both peak energy and compression wave strength depend primarily on dielectric thickness and secondarily on actuator length although this is not universal in the case of energy necessitating examination of alternative calculation strategies. Peak power is mainly dependent on actuator length which is inconsistent with schlieren data as expected. Higher pulse frequency produces higher pulse energy, but is primarily attributed to heating of the actuator and power supply components. This effect is mainly observed for short actuators. Pulse energy increases as peak voltage to the power 3.5. This behavior is similar to observations of energy and thrust for ac-DBD plasma actuators suggesting that aspects of lumped-element circuit models may be applicable for optimizing ns-DBD performance.

  5. Characterization of nanosecond pulse driven dielectric barrier discharge plasma actuators for aerodynamic flow control

    Science.gov (United States)

    Dawson, Robert; Little, Jesse

    2013-03-01

    Positive polarity nanosecond pulse driven dielectric barrier discharge (ns-DBD) plasma actuators are studied experimentally in quiescent atmosphere. Pulse energy and instantaneous pulse power (hereafter referred to as energy and power) are calculated using simultaneous voltage and current measurements. Electrical characteristics are evaluated as a function of peak voltage, pulse frequency, discharge length, and dielectric thickness. Schlieren imaging is used to provide a relative estimate of discharge energy that is coupled to the near surface gas as heat for the same parameters. Characteristics of the DBD load have a substantial effect on the individual voltage and current traces which are reflected in the energy and power values. Power is mainly dependent on actuator length which is inconsistent with schlieren data as expected. Higher per unit length energy indicates a stronger compression wave for a given actuator geometry, but this is not universally true across different actuators suggesting some constructions more efficiently couple energy to the gas. Energy and compression wave strength are linearly related. Higher pulse frequency produces higher energy but is primarily attributed to heating of the actuator and power supply components and not to an optimal discharge frequency. Both energy and wave strength increase as peak voltage to the power of approximately 3.5 over a substantial range similar to ac-DBD plasma actuators.

  6. Effect of bottling and storage on the migration of plastic constituents in Spanish bottled waters.

    Science.gov (United States)

    Guart, Albert; Bono-Blay, Francisco; Borrell, Antonio; Lacorte, Silvia

    2014-08-01

    Bottled water is packaged in either glass or, to a large extent, in plastic bottles with metallic or plastic caps of different material, shape and colour. Plastic materials are made of one or more monomers and several additives that can eventually migrate into water, either during bottle manufacturing, water filling or storage. The main objective of the present study was to carry out a comprehensive assessment of the quality of the Spanish bottled water market in terms of (i) migration of plastic components or additives during bottling and during storage and (ii) evaluation of the effect of the packaging material and bottle format on the migration potential. The compounds investigated were 5 phthalates, diethylhexyl adipate, alkylphenols and bisphenol A. A set of 362 bottled water samples corresponding to 131 natural mineral waters and spring waters sources and 3 treated waters of several commercial brands were analysed immediately after bottling and after one-year storage (a total of 724 samples). Target compounds were detected in 5.6% of the data values, with diethyl hexyl phthalate and bisphenol A being the most ubiquitous compounds detected. The total daily intake was estimated and a comparison with reference values was indicated. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Effect of substrate temperature on the structure of amorphous oxygenated hydrocarbon films grown with a pulsed supersonic methane plasma flow

    Energy Technology Data Exchange (ETDEWEB)

    Fedoseeva, Yu. V., E-mail: fedoseeva@niic.nsc.ru [Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Pozdnyakov, G.A. [Khristianovich Institute of Theoretical and Applied Mechanics, SB RAS, Novosibirsk 630090 (Russian Federation); Okotrub, A.V.; Kanygin, M.A. [Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Nastaushev, Yu. V. [Rzhanov Institute of Semiconductor Physics SB RAS, Novosibirsk 630090 (Russian Federation); Vilkov, O.Y. [St. Petersburg State University, St. Petersburg 198504 (Russian Federation); Bulusheva, L.G. [Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation)

    2016-11-01

    Highlights: • A deposition of supersonic methane plasma flow on silicon substrate produces amorphous oxygenated hydrocarbon (CO{sub x}H{sub y}) film. • The thickness, composition, and wettability of the film depend on the substrate temperature. • A rise of the substrate temperature from 500 to 700 °C promotes the sp{sup 3}-hybridization carbon formation. - Abstract: Since amorphous oxygenated hydrocarbon (CO{sub x}H{sub y}) films are promising engineering materials a study of the structure and composition of the films depending on the conditions of synthesis is important for controlling of their physicochemical properties. Here, we used the methods of scanning and transmission electron microscopy, X-ray photoelectron, near-edge X-ray absorption fine structure, Fourier transform infrared and Raman spectroscopy to reveal changes in the chemical connectivity of CO{sub x}H{sub y} films grown on silicon substrates heated to 300, 500, and 700 °C using a supersonic flow of methane plasma. It was found that the CO{sub x}H{sub y} films, deposited at 300 and 500 °C, were mainly composed of the sp{sup 2}-hybridized carbon areas with various oxygen species. A rise of the substrate temperature caused an increase of the portion of tetrahedral carbon atoms as well as carboxyl and hydroxyl groups. With growth of the substrate temperature, the film thickness reduced monotonically from 400 to 180 nm, while the film adhesion improved substantially. The films, deposited at lower temperatures, showed high hydrophilicity due to porosity and presence of oxygenated groups both at the surface and in the bulk.

  8. A differentially pumped argon plasma in the linear plasma generator Magnum-PSI: gas flow and dynamics of the ionized fraction

    NARCIS (Netherlands)

    van Eck, H. J. N.; Hansen, T. A. R.; Kleyn, A. W.; van der Meiden, H. J.; D.C. Schram,; van Emmichoven, P. A. Zeijlma

    2011-01-01

    Magnum-PSI is a linear plasma generator designed to reach the plasma-surface interaction (PSI) regime of ITER and nuclear fusion reactors beyond ITER. To reach this regime, the influx of cold neutrals from the source must be significantly lower than the plasma flux reaching the target. This is

  9. Influence of ambient air on the flowing afterglow of an atmospheric pressure Ar/O2 radiofrequency plasma

    CERN Document Server

    Duluard, C Y; Hubert, J; Reniers, F

    2016-01-01

    The influence of ambient air on the flowing afterglow of an atmospheric pressure Ar/O2 radiofrequency plasma has been investigated experimentally. Spatially resolved mass spectrometry and laser induced fluorescence on OH radicals were used to estimate the intrusion of air in between the plasma torch and the substrate as a function of the torch-to-substrate separation distance. No air is detected, within the limits of measurement uncertainties, for separation distances smaller than 5 mm. For larger distances, the effect of ambient air can no longer be neglected, and radial gradients in the concentrations of species appear. The Ar 4p population, determined through absolute optical emission spectroscopy, is seen to decrease with separation distance, whereas a rise in emission from the N2(C--B) system is measured. The observed decay in Ar 4p and N2(C) populations for separation distances greater than 9mm is partly assigned to the increasing collisional quenching rate by N2 and O2 molecules from the entrained air....

  10. Dissociation of carbon dioxide using a microhollow cathode discharge plasma reactor: effects of applied voltage, flow rate and concentration

    Science.gov (United States)

    Taylan, O.; Berberoglu, H.

    2015-02-01

    This paper reports an experimental study on dissociating carbon dioxide (CO2) using a microhollow cathode discharge (MHCD) plasma reactor operated at 1 atm. The MHCD plasma reactors can be a promising technology for dissociating gases, including CO2, as they do not require catalysts, they operate at around room temperature, and can be inexpensively built and operated. In this study, CO2 balanced with the carrier gas argon (Ar) was fed through the MHCD reactor, and parametric experiments were conducted to investigate the effects of applied voltage, flow rate, and CO2 mole fraction in the influent on the composition of the products, energy conversion efficiency, and yield. Within the investigated parameter ranges, the maximum energy conversion efficiency of 14% was achieved when the specific energy input was 1.1 eV mol-1, whereas the maximum CO yield of 10.5% was achieved when the specific energy input was 4 eV mol-1. The results also showed that diluting CO2 with Ar increased the yield at an expense of a decrease in energy conversion efficiency. The results of this study provide insights for operating MHCD reactors for efficient gas dissociation at atmospheric pressure.

  11. Aerospace Thematic Workshop (4th): Fundamentals of Aerodynamic Flow and Combustion Control by Plasmas

    Science.gov (United States)

    2013-04-01

    almost complete lack of low temperature kinetic reactivity, while n- alkane hydrocarbon fuels with long chains of secondary C-H bonds have the largest...valve for subsequent analysis with gas chromatography . Experiments were performed by fixing the flow rate or residence time in the reactor, and...700 and 950 K characterized by - scission of the initial alkyl radical to form alkenes and smaller alkanes . Distribution A: Approved for public

  12. Collaborative Research: A Model of Partially Ionized Plasma Flows with Kinetic Treatment of Neutral Atoms and Nonthermal Ions

    Energy Technology Data Exchange (ETDEWEB)

    Pogorelov, Nikolai [Univ. of Alabama, Huntsville, AL (United States); Zhang, Ming [Florida Inst. of Technology, Melbourne, FL (United States)

    2016-07-31

    Interactions of flows of partially ionized, magnetized plasma are frequently accompanied by the presence of both thermal and non-thermal (pickup) ion components. Such interactions cannot be modeled using traditional MHD equations and require more advanced approaches to treat them. If a nonthermal component of ions is formed due to charge exchange and collisions between the thermal (core) ions and neutrals, it experiences the action of magnetic field, its distribution function is isotropized, and it soon acquires the velocity of the ambient plasma without being thermodynamically equilibrated. This situation, e. g., takes place in the outer heliosphere –- the part of interstellar space beyond the solar system whose properties are determined by the solar wind interaction with the local interstellar medium. This is also possible in laboratory, at million degrees and above, when plasma is conducting electricity far too well, which makes Ohmic heating ineffective. To attain the target temperatures one needs additional heating eventually playing a dominant role. Among such sources is a so-called neutral particle beam heating. This is a wide-spread technique (Joint European Torus and International Thermonuclear Experimental Reactor experiments) based on the injection of powerful beams of neutral atoms into ohmically preheated plasma. In this project we have investigated the energy and density separation between the thermal and nonthermal components in the solar wind and interstellar plasmas. A new model has been developed in which we solve the ideal MHD equations for mixture of all ions and the kinetic Boltzmann equation to describe the transport of neutral atoms. As a separate capability, we can treat the flow of neutral atoms in a multi-component fashion, where neutral atoms born in each thermodynamically distinct region are governed by the Euler gas dynamic equations. We also describe the behavior of pickup ions either kinetically, using the Fokker--Planck equation

  13. Collaborative Research: A Model of Partially Ionized Plasma Flows with Kinetic Treatment of Neutral Atoms and Nonthermal Ions

    Energy Technology Data Exchange (ETDEWEB)

    Pogorelov, Nikolai [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and; Zhang, Ming [Florida Inst. of Technology, Melbourne, FL (United States). Physics and Space Sciences Dept.; Borovikov, Sergey [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and Aeronomic Research; Heerikhuisen, Jacob [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and Aeronomic Research; Zank, Gary [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and Aeronomic Research; Gamayunov, Konstantin [Florida Inst. of Technology, Melbourne, FL (United States). Physics and Space Sciences Dept.; Colella, Phillip [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-07-31

    Interactions of flows of partially ionized, magnetized plasma are frequently accompanied by the presence of both thermal and non-thermal (pickup) ion components. Such interactions cannot be modeled using traditional MHD equations and require more advanced approaches to treat them. If a nonthermal component of ions is formed due to charge exchange and collisions between the thermal (core) ions and neutrals, it experiences the action of magnetic field, its distribution function is isotropized, and it soon acquires the velocity of the ambient plasma without being thermodynamically equilibrated. This situation, e. g., takes place in the outer heliosphere - the part of interstellar space beyond the solar system whose properties are determined by the solar wind interaction with the local interstellar medium. This is also possible in laboratory, at million degrees and above, when plasma is conducting electricity far too well, which makes Ohmic heating ineffective. To attain the target temperatures one needs additional heating eventually playing a dominant role. Among such sources is a so-called neutral particle beam heating. This is a wide-spread technique (Joint European Torus and International Thermonuclear Experimental Reactor experiments) based on the injection of powerful beams of neutral atoms into ohmically preheated plasma. In this project we have investigated the energy and density separation between the thermal and nonthermal components in the solar wind and interstellar plasmas. A new model has been developed in which we solve the ideal MHD equations for mixture of all ions and the kinetic Boltzmann equation to describe the transport of neutral atoms. As a separate capability, we can treat the flow of neutral atoms in a multi-component fashion, where neutral atoms born in each thermodynamically distinct regions are governed by the Euler gas dynamic equations. We also describe the behavior of pickup ions either kinetically, using the Fokker–Planck equation, or

  14. Ageing is a process where the growth effect of neuronal noradrenaline changes progressively in favour of the flow mediated, neurodegenerative and inflammatory effect of plasma noradrenaline.

    Science.gov (United States)

    Crotty, T P

    2016-08-01

    The noradrenaline stimulus has two components, one excitor, the other inhibitory. Neuronal noradrenaline is the excitor component and plasma noradrenaline is the inhibitory. The balance of effect between the two, the noradrenergic balance, is the controlled variable of the sympathetic system and determines the effect of noradrenaline. Neuronal noradrenaline stimulates tissues by diffusion from their sympathetic nerve endings, plasma noradrenaline does so by diffusion from their microcirculations. Changes in microcirculatory flow, by altering the flow mediated effect of plasma noradrenaline, are mainly responsible for altering the noradrenergic balance in the peripheral tissues; changes in CSF flow are speculated to be mainly responsible for doing the same in the brain, by altering the balance between synaptic noradrenaline in the brain and nonsynaptic noradrenaline in the subarachnoid CSF. When plasma noradrenaline alters the noradrenergic balance it triggers afferent sympathetic activity that alerts hypothalamic neurons to the event and they restore the balance and tissue homeostasis, within milliseconds, by adjusting the level of efferent sympathetic activity they project back to the affected tissue. Because the restoration is so rapid the effect of plasma noradrenaline is normally unobservable and dismissed as not having occurred. Because the hypothalamus is not involved with the responses of isolated canine lateral saphenous vein segments to noradrenaline, the effects of plasma noradrenaline in that preparation are not countered by reactive efferent activity and, consequently, are readily apparent in it. Quantitatively, they have been found to be a function of microcirculatory flow and noradrenaline concentration and, qualitatively, to be inhibitory, dilator, pro inflammatory and neurodegenerative. In life, due to a progressive increase in plasma noradrenaline concentration and, more so, in microcirculatory flow, the noradrenergic balance moves progressively in

  15. Chemical, microbial and physical evaluation of commercial bottled waters in greater Houston area of Texas.

    Science.gov (United States)

    Saleh, Mahmoud A; Abdel-Rahman, Fawzia H; Woodard, Brooke B; Clark, Shavon; Wallace, Cecil; Aboaba, Adetoun; Zhang, Wenluo; Nance, James H

    2008-03-01

    Due to the increased demand and consumption of bottled water in the United States, there has been a growing concern about the quality of this product. Retail outlets sell local as well as imported bottled water to consumers. Three bottles for each of 35 different brands of bottled water were randomly collected from local grocery stores in the greater Houston area. Out of the 35 different brands, 16 were designated as spring water, 11 were purified and/or fortified tap water, 5 were carbonated water and 3 were distilled water. Chemical, microbial and physical properties of all samples were evaluated including pH, conductivity, bacteria counts, anion concentration, trace metal concentration, heavy metal and volatile organics concentration were determined in all samples. Inductively coupled plasma/mass spectrometry (ICPMS) was used for elemental analysis, gas chromatography with electron capture detector (GCECD) as well as gas chromatography mass spectrometry (GCMS) were used for analysis of volatile organics, ion chromatography (IC) and selective ion electrodes were used for the analysis of anions. Bacterial identification was performed using the Biolog software (Biolog, Inc., Hayward, Ca, USA). The results obtained were compared with guidelines of drinking water recommended by the International Bottled Water Association (IBWA), United States Food and Drug Administration (FDA), United States Environmental Protection Agency (EPA) and the World Health Organization (WHO) drinking water standard. The majority of the analyzed chemicals were below their respective drinking water standards for maximum admissible concentrations (MAC). Volatile organic chemicals were found to be below detection limits. Four of the 35 brands of the bottled water samples analyzed were found to be contaminated with bacteria.

  16. STATISTICS OF THE VELOCITY GRADIENT TENSOR IN SPACE PLASMA TURBULENT FLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Consolini, Giuseppe; Marcucci, Maria Federica; Pallocchia, Giuseppe [INAF-Istituto di Astrofisica e Planetologia Spaziali, Roma (Italy); Materassi, Massimo, E-mail: giuseppe.consolini@iaps.inaf.it [Istituto dei Sistemi Complessi, CNR, Sesto Fiorentino (Italy)

    2015-10-10

    In the last decade, significant advances have been presented for the theoretical characterization and experimental techniques used to measure and model all of the components of the velocity gradient tensor in the framework of fluid turbulence. Here, we attempt the evaluation of the small-scale velocity gradient tensor for a case study of space plasma turbulence, observed in the Earth's magnetosheath region by the CLUSTER mission. In detail, we investigate the joint statistics P(R, Q) of the velocity gradient geometric invariants R and Q, and find that this P(R, Q) is similar to that of the low end of the inertial range for fluid turbulence, with a pronounced increase in the statistics along the so-called Vieillefosse tail. In the context of hydrodynamics, this result is referred to as the dissipation/dissipation-production due to vortex stretching.

  17. Prospects and difficulties in TiO₂ nanoparticles analysis in cosmetic and food products using asymmetrical flow field-flow fractionation hyphenated to inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    López-Heras, Isabel; Madrid, Yolanda; Cámara, Carmen

    2014-06-01

    In this work, we proposed an analytical approach based on asymmetrical flow field-flow fractionation combined to an inductively coupled plasma mass spectrometry (AsFlFFF-ICP-MS) for rutile titanium dioxide nanoparticles (TiO2NPs) characterization and quantification in cosmetic and food products. AsFlFFF-ICP-MS separation of TiO2NPs was performed using 0.2% (w/v) SDS, 6% (v/v) methanol at pH 8.7 as the carrier solution. Two problems were addressed during TiO2NPs analysis by AsFlFFF-ICP-MS: size distribution determination and element quantification of the NPs. Two approaches were used for size determination: size calibration using polystyrene latex standards of known sizes and transmission electron microscopy (TEM). A method based on focused sonication for preparing NPs dispersions followed by an on-line external calibration strategy based on AsFlFFF-ICP-MS, using rutile TiO2NPs as standards is presented here for the first time. The developed method suppressed non-specific interactions between NPs and membrane, and overcame possible erroneous results obtained when quantification is performed by using ionic Ti solutions. The applicability of the quantification method was tested on cosmetic products (moisturizing cream). Regarding validation, at the 95% confidence level, no significant differences were detected between titanium concentrations in the moisturizing cream prior sample mineralization (3865±139 mg Ti/kg sample), by FIA-ICP-MS analysis prior NPs extraction (3770±24 mg Ti/kg sample), and after using the optimized on-line calibration approach (3699±145 mg Ti/kg sample). Besides the high Ti content found in the studied food products (sugar glass and coffee cream), TiO2NPs were not detected. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Asymmetric flow field-flow fractionation coupled to inductively coupled plasma mass spectrometry for the quantification of quantum dots bioconjugation efficiency.

    Science.gov (United States)

    Menéndez-Miranda, Mario; Encinar, Jorge Ruiz; Costa-Fernández, José M; Sanz-Medel, Alfredo

    2015-11-27

    Hyphenation of asymmetric flow field-flow fractionation (AF4) to an on-line elemental detection (inductively coupled plasma-mass spectrometry, ICP-MS) is proposed as a powerful diagnostic tool for quantum dots bioconjugation studies. In particular, conjugation effectiveness between a "model" monoclonal IgG antibody (Ab) and CdSe/ZnS core-shell Quantum Dots (QDs), surface-coated with an amphiphilic polymer, has been monitored here by such hybrid AF4-ICP-MS technique. Experimental conditions have been optimized searching for a proper separation between the sought bioconjugates from the eventual free reagents excesses employed during the bioconjugation (QDs and antibodies). Composition and pH of the carrier have been found to be critical parameters to ensure an efficient separation while ensuring high species recovery from the AF4 channel. An ICP-MS equipped with a triple quadropole was selected as elemental detector to enable sensitive and reliable simultaneous quantification of the elemental constituents, including sulfur, of the nanoparticulated species and the antibody. The hyphenated technique used provided nanoparticle size-based separation, elemental detection, and composition analysis capabilities that turned out to be instrumental in order to investigate in depth the Ab-QDs bioconjugation process. Moreover, the analytical strategy here proposed allowed us not only to clearly identify the bioconjugation reaction products but also to quantify nanoparticle:antibodies bioconjugation efficiency. This is a key issue in future development of analytical and bioanalytical photoluminescent QDs applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Detection and characterization of silver nanoparticles in aqueous matrices using asymmetric-flow field flow fractionation with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Hoque, Md Ehsanul; Khosravi, Kambiz; Newman, Karla; Metcalfe, Chris D

    2012-04-13

    Engineered nanomaterials (EN) may be released into the environment as a result of their use in various consumer products. Silver nanoparticles (nAg) are widely used as an antimicrobial agent in personal care and household products, and in textiles. Since there is high potential for nAg to be released into municipal wastewater and then discharged into the aquatic environment, there is a need to develop methods for the analysis of these materials in aqueous matrices. Asymmetric-flow field flow fractionation (AF4) with on-line detection by ultra violet-visible (UV-Vis) spectroscopy or inductively coupled plasma mass spectrometry (ICP-MS) was used to detect and characterize nAg in aqueous matrices. Analysis of a mixture of 20, 40 and 60 nm nAg standards suspended in water resulted in a well resolved fractogram. Retention times of nAg separated by AF4 were correlated with the particle sizes of the standards. The limit of detection (LOD) for analysis of nAg using the on-line AF4/ICP-MS method was 0.80 ng mL(-1). Two calibration approaches (i.e., external calibration and standard addition) were used to quantify nAg concentrations, and both methods gave similar results. Using the on-line AF4/ICP-MS analytical method, nano-sized Ag was detected and quantified in untreated wastewater (i.e., influent) collected from a wastewater treatment plant. The concentration and the modal size of nAg in the influent were 1.90 ng mL(-1) and 9.3 nm respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Characterization and quantification of silver nanoparticles in nutraceuticals and beverages by asymmetric flow field flow fractionation coupled with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Ramos, K; Ramos, L; Cámara, C; Gómez-Gómez, M M

    2014-12-05

    This study evaluated the feasibility of asymmetric flow field flow fractionation coupled with inductively coupled plasma mass spectrometry (AF4-ICP-MS) for separation, characterization and quantification of silver nanoparticles (AgNPs) in complex nutraceutical and beverage samples. For improved determination, different analysis conditions were proposed depending on the NP size, i.e. below 20 nm and in the 20-60 nm range. After optimization of the different experimental parameters affecting the AF4 separation process and the analyte detection, the proposed methods showed a wide dynamic linear range (i.e., in the 10-1000 μg L(-1)) and limits of detection below 28 ng L(-1). A previous probe ultrasonication for 90 s (corresponding to 45 pulses of 2 s) of the tested samples resulted in complete AgNPs disaggregation. As a result, a fast accurate determination was achieved (complete analysis was done in ca. 37 min). The practicality of the proposed methodology for the intended determination was demonstrated by successful determination of the AgNPs present in a variety of nutraceuticals and a beverage at concentration levels in the 0.7-29.5×10(3) μg L(-1) range. A good agreement was observed among these concentration data and those determined by more conventional sample preparation techniques, such as ultracentrifugation and acid digestion. Also, the estimated NP sizes using AF4 compared satisfactorily with those determined by image techniques, i.e. transmission electron microscopy (TEM). All together demonstrated the utility of this novel analytical methodology for the analysis of AgNPs of different size in complex matrices. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Experimental investigation on the impacts of ignition energy and position on ignition processes in supersonic flows by laser induced plasma

    Science.gov (United States)

    An, Bin; Wang, Zhenguo; Yang, Leichao; Li, Xipeng; Zhu, Jiajian

    2017-08-01

    Cavity ignition of a model scramjet combustor fueled by ethylene was achieved through laser induced plasma, with inflow conditions of Ma = 2.92, total temperature T0 = 1650 K and stagnation pressure P0 = 2.6 MPa. The overall equivalent ratio was kept at 0.152 for all the tests. The ignition processes at different ignition energies and various ignition positions were captured by CH∗ and OH∗ chemiluminescence imaging. The results reveal that the initial flame kernel is carried to the cavity leading edge by the recirculation flow, and resides there for ∼100 μs before spreading downstream. The ignition time can be reduced, and the possibility of successful ignition for single laser pulse can be promoted by enhancing ignition energy. The scale and strength of the initial flame kernel is influenced by both the ignition energy and position. In present study, the middle part of the cavity is the best position for ignition, as it keeps a good balance between the strength of initial flame kernel and the impacts of strain rate in recirculation flow.

  2. Electromagnetic phenomena in granular flows in the laboratory and dusty plasmas in geophysics and astrophysics

    Science.gov (United States)

    Lathrop, Daniel; Eiskowitz, Skylar; Rojas, Ruben

    2017-11-01

    In clouds of suspended particles, collisions electrify particles and the clouds produce electric potential differences over large scales. This is seen in the atmosphere as lightning in thunderstorms, thundersnow, dust storms, and volcanic ash plumes, but it is a general phenomena in granular systems. The electrification process is not well understood. To investigate the relative importance of particle material properties and collective phenomena in granular and atmospheric electrification, we used several tabletop experiments that excite particle-laden flows. Various electromagnetic phenomena ensue. Measured electric fields result from capacitive and direct charge transfer to electrodes. These results suggest that while particle properties do matter (as previous investigations have shown), macroscopic electrification of granular flows is somewhat material independent and large-scale collective phenomena play a major role. As well, our results on charge separation and Hall effects suggest a very different view of the dynamics of clouds, planetary rings, and cold accretion disks in proto-planetary systems. We gratefully acknowledge past funding from the Julian Schwinger Foundation as well as the Ph.D. work of Freja Nordsiek.

  3. Chemical quality of bottled waters: a review.

    Science.gov (United States)

    Diduch, Malwina; Polkowska, Zaneta; Namieśnik, Jacek

    2011-01-01

    Bottled water has become very popular for quenching thirst and as a dietary (mineral) supplement. The plethora of natural mineral waters precludes any unequivocal system of classification, which makes it difficult for the consumer to choose a water with properties that suits him/her exactly. The ever-increasing popularity of bottled waters means that it is of the utmost importance to determine not only their mineral content, but above all, the content of possible contaminants, especially organic ones. In this respect bottled waters are a special case, because apart from organic contamination from the environment, the water may become secondarily contaminated as a result of its being improperly transported and stored. Pesticides, volatile organic compounds, and carbonyl compounds have been detected in samples of bottled water. This overview shows the available published information on levels of inorganic constituents and organic contaminants in samples of bottled water in the context of sample preparation procedures and analytical techniques. © 2011 Institute of Food Technologists®

  4. Nonequilibrium Phenomena in Plasmas

    CERN Document Server

    Sharma, A Surjalal

    2005-01-01

    The complexity of plasmas arises mainly from their inherent nonlinearity and far from equilibrium nature. The nonequilibrium behavior of plasmas is evident in the natural settings, for example, in the Earth's magnetosphere. Similarly, laboratory plasmas such as fusion bottles also have their fair share of complex behavior. Nonequilibrium phenomena are intimately connected with statistical dynamics and form one of the growing research areas in modern nonlinear physics. These studies encompass the ideas of self-organization, phase transition, critical phenomena, self-organized criticality and turbulence. This book presents studies of complexity in the context of nonequilibrium phenomena using theory, modeling, simulations, and experiments, both in the laboratory and in nature.

  5. Experiment-Model Comparisons of Turbulence, Transport, and Flows in a Magnetized Linear Plasma Using a Global Two-Fluid Braginskii Solver

    Science.gov (United States)

    Gilmore, M.; Fisher, D. M.; Kelly, R. F.; Hatch, M. W.; Rogers, B. N.

    2017-10-01

    Ongoing experiments and numerical modeling of the dynamics of electrostatic turbulence and transport in the presence of flow shear are being conducted in helicon plasmas in the linear HelCat (Helicon-Cathode) device. Modeling is being done using GBS, a 3D, global two-fluid Braginskii code that solves self-consistently for plasma equilibrium as well as fluctuations. Past experimental measurements of flows have been difficult to reconcile with simple expectations, such as azimuthal flows being dominated by Er x Bz rotation. Therefore, recent measurements have focused on understanding plasma flows, and the role of neutral dynamics. In the model, a set of two-fluid drift-reduced Braginskii equations are evolved using the Global Braginskii Solver Code (GBS). For low-field helicon-sourced Ar plasmas a non-negligible cross-field thermal collisional term must be added to shift the electric potential in the ion momentum and vorticity equations as the ions are unmagnetized. Significant radially and axially dependent neutral profiles are also included in the simulations to try and match those observed in HelCat. Ongoing simulations show a mode dependence on the axial magnetic field along with strong axial variations that suggest drift waves may be important in the low-field case. Supported by U.S. National Science Foundation Award 1500423.

  6. Differential effect of T-type voltage-gated calcium channel disruption on renal plasma flow and glomerular filtration rate in vivo

    DEFF Research Database (Denmark)

    Thuesen, Anne D; Andersen, Henrik; Cardel, Majken

    2014-01-01

    of two T-type Cav knock-out mice strains. Continuous recordings of blood pressure and heart rate, and para-aminohippurate clearance (renal plasma flow) and inulin clearance (GFR) were performed in conscious, chronically catheterized, wild type and Cav 3.1-/- and Cav 3.2-/- mice. Contractility of afferent...

  7. Methods for counting residual leukocytes in leukocyte-depleted plasma-a comparison between a routine hematology instrument, the Nageotte chamber, flow cytometry, and a fluorescent microscopy analyzer.

    Science.gov (United States)

    Petersson, Annika; Ekblom, Kim

    2017-05-01

    Counting very low levels of leukocytes is technically challenging but mandatory for quality control of leukocyte-depleted plasma. Established assays, such as flow cytometry and counting in the Nageotte chamber, are laborious and expensive. The aim of this study was to test two alternative assays, the cerebrospinal fluid program in the routine hematology analyzer ADVIA 2120 and a fluorescence microscopy analyzer, the ADAM-rWBC. Linearity, accuracy, and precision were established for the ADVIA 2120, the ADAM-rWBC analyzer and the Nageotte chamber with flow cytometry as the reference method. Two hundred consecutive leukocyte-depleted donor plasma samples were also tested. The ADAM-rWBC analyzer and the Nageotte chamber fulfilled all quality requirements. Flow cytometry fulfilled the requirements for linearity and precision. The ADVIA 2120 analyzer did not fully reach the quality criteria, and flow cytometry did not reach quality criteria on accuracy. No false-positive results on donor plasma samples were recorded. The ADAM-rWBC is suitable for the purpose of quality control of residual leukocytes in leukocyte-depleted plasma. For the ADVIA 2120, further improvements and studies are needed to reach the quality requirements stated in this study. © 2017 AABB.

  8. Relativistic Shear Flow between Electron-Ion and Electron-Positron Plasmas and Astrophysical Applications

    Science.gov (United States)

    Liang, Edison; Fu, Wen; Böttcher, Markus

    2017-10-01

    We present particle-in-cell simulation results of relativistic shear boundary layers between electron-ion and electron-positron plasmas and discuss their potential applications to astrophysics. Specifically, we find that in the case of a fast electron-positron spine surrounded by a slow-moving or stationary electron-ion sheath, lepton acceleration proceeds in a highly anisotropic manner due to electromagnetic fields created at the shear interface. While the highest-energy leptons still produce a beaming pattern (as seen in the quasi-stationary frame of the sheath) of order 1/Γ, where Γ is the bulk Lorentz factor of the spine, for lower-energy particles, the beaming is much less pronounced. This is in stark contrast to the case of pure electron-ion shear layers, in which anisotropic particle acceleration leads to significantly narrower beaming patterns than 1/Γ for the highest-energy particles. In either case, shear-layer acceleration is expected to produce strongly angle-dependent lepton (hence, emanating radiation) spectra, with a significantly harder spectrum in the forward direction than viewed from larger off-axis angles, much beyond the regular Doppler boosting effect from a co-moving isotropic lepton distribution. This may solve the problem of the need for high (and apparently arbitrarily chosen) minimum Lorentz factors of radiating electrons, often plaguing current blazar and GRB jet modeling efforts.

  9. Plasma flows and magnetic field interplay during the formation of a pore

    Science.gov (United States)

    Ermolli, I.; Cristaldi, A.; Giorgi, F.; Giannattasio, F.; Stangalini, M.; Romano, P.; Tritschler, A.; Zuccarello, F.

    2017-04-01

    Aims: Recent simulations of solar magneto-convection have offered new levels of understanding of the interplay between plasma motions and magnetic fields in evolving active regions. We aim at verifying some aspects of the formation of magnetic regions derived from recent numerical studies in observational data. Methods: We studied the formation of a pore in the active region (AR) NOAA 11462. We analysed data obtained with the Interferometric Bidimensional Spectrometer (IBIS) at the Dunn Solar Telescope on April 17, 2012, consisting of full Stokes measurements of the Fe I 617.3 nm lines. Furthermore, we analysed SDO/HMI observations in the continuum and vector magnetograms derived from the Fe I 617.3 nm line data taken from April 15 to 19, 2012. We estimated the magnetic field strength and vector components and the line-of-sight (LOS) and horizontal motions in the photospheric region hosting the pore formation. We discuss our results in light of other observational studies and recent advances of numerical simulations. Results: The pore formation occurs in less than 1 h in the leading region of the AR. We observe that the evolution of the flux patch in the leading part of the AR is faster (Movies associated to Figs. 1 and 4 are available at http://www.aanda.org

  10. Flow

    DEFF Research Database (Denmark)

    2009-01-01

    Flow er en positiv, koncentreret tilstand, hvor al opmærksomhed er samlet om en bestemt aktivitet, som er så krævende og engagerende, at man må anvende mange mentale ressourcer for at klare den. Tidsfornemmelsen forsvinder, og man glemmer sig selv. 'Flow' er den første af en række udsendelser om...

  11. Ir Thermographic Measurements of Temperatures and Heat Fluxes in Hypersonic Plasma Flow

    Science.gov (United States)

    Cardone, G.; Tortora, G.; del Vecchio, A.

    2005-02-01

    The technological development achieved in instruments and methodology concerning both flights and ground hypersonic experiment (employed in space plane planning) goes towards an updating and a standardization of the heat flux technical measurements. In fact, the possibility to simulate high enthalpy flow relative to reentry condition by hypersonic arc-jet facility needs devoted methods to measure heat fluxes. Aim of this work is to develop an experimental numerical technique for the evaluation of heat fluxes over Thermal Protection System (TPS) by means of InfraRed (IR) thermographic temperature measurements and a new heat flux sensor (IR-HFS). We tackle the numerical validation of IR-HFS, apply the same one to the Hyflex nose cap model and compare the obtained results with others ones obtained by others methodology.

  12. Ultracold neutron storage in a fluid-walled bottle

    Science.gov (United States)

    Bates, J. C.

    1982-04-01

    Theoretically possible wall-loss probabilities for ultracold neutrons stored in solid-walled bottles have not been achieved in practice, but preliminary measurements with a fluid-walled bottle seem promising.

  13. Observation of an edge coherent mode and poloidal flow in the electron cyclotron wave induced high β{sub p} plasma in QUEST

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Santanu, E-mail: sbanerje@ipr.res.in; Mishra, K. [Institute for Plasma Research, Bhat, Gandhinagar 382428, Gujarat (India); Zushi, H.; Mahira, Y.; Tashima, S.; Onchi, T.; Nagashima, Y.; Hanada, K.; Nakamura, K.; Idei, H.; Hasegawa, M.; Fujisawa, A.; Kuzmin, A.; Matsuoka, K. [RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580 (Japan); Nishino, N. [Mechanical System Engineering, Hiroshima University, Hiroshima 739-8527 (Japan); Ejiri, A.; Yamaguchi, T. [Graduate School of Frontier Sciences, Tokyo University, Kashiwa 277-8561 (Japan)

    2016-08-15

    Fluctuations are measured in the edge and scrape-off layer (SOL) of QUEST using fast visible imaging diagnostic. Electron cyclotron wave injection in the Ohmic plasma features excitation of low frequency coherent fluctuations near the separatrix and enhanced cross-field transport. Plasma shifts from initial high field side limiter bound (inboard limited, IL) towards inboard poloidal null (IPN) configuration with steepening of the density profile at the edge. This may have facilitated the increased edge and SOL fluctuation activities. Observation of the coherent mode, associated plasma flow, and particle out-flux, for the first time in the IPN plasma configuration in a spherical tokamak may provide further impetus to the edge and SOL turbulence studies in tokamaks.

  14. Diagnosing collisions of magnetized, high energy density plasma flows using a combination of collective Thomson scattering, Faraday rotation, and interferometry (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Swadling, G. F., E-mail: swadling@imperial.ac.uk; Lebedev, S. V.; Hall, G. N.; Patankar, S.; Stewart, N. H.; Smith, R. A.; Burdiak, G. C.; Grouchy, P. de; Skidmore, J.; Suttle, L.; Suzuki-Vidal, F.; Bland, S. N.; Kwek, K. H.; Pickworth, L.; Bennett, M.; Hare, J. D. [Plasma Physics Group, Imperial College, London SW6 7LZ (United Kingdom); Harvey-Thompson, A. J. [Sandia National Laboratory, Albuquerque, New Mexico 87185-1193 (United States); Rozmus, W. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Yuan, J. [Key Laboratory of Pulsed Power, Institute of Fluid Physics, CAE, Mianyang 621900 (China)

    2014-11-15

    A suite of laser based diagnostics is used to study interactions of magnetised, supersonic, radiatively cooled plasma flows produced using the Magpie pulse power generator (1.4 MA, 240 ns rise time). Collective optical Thomson scattering measures the time-resolved local flow velocity and temperature across 7–14 spatial positions. The scattering spectrum is recorded from multiple directions, allowing more accurate reconstruction of the flow velocity vectors. The areal electron density is measured using 2D interferometry; optimisation and analysis are discussed. The Faraday rotation diagnostic, operating at 1053 nm, measures the magnetic field distribution in the plasma. Measurements obtained simultaneously by these diagnostics are used to constrain analysis, increasing the accuracy of interpretation.

  15. Determinants of using pacifier and bottle feeding

    Directory of Open Access Journals (Sweden)

    Gabriela dos Santos Buccini

    2014-08-01

    Full Text Available OBJECTIVE To analyze the factors associated with the use of pacifiers and/or bottle feeding in infants aged under one year. METHODS This is a cross-sectional study with 34,366 children and using data from the database of the 2nd Nationwide Survey of Breastfeeding Prevalence performed in the Brazilian capitals and Federal District in 2008. Cluster sampling was used. The questionnaire included questions about the use of artificial nipples in the last 24 hours. The analysis considered three outcomes: exclusive use of pacifier, exclusive use of bottle feeding, and use of artificial nipples (pacifier and bottle feeding. Prevalence ratios were obtained using Poisson regression with robust variance following a hierarchical model. RESULTS The following factors were associated with exclusive use of the pacifier: mother working outside the home, primiparity, child was not breastfed within the first hour, and child had consumed tea on the first day at home. The following factors were associated with exclusive use of bottle feeding: mother working outside the home, primiparity, low birth weight, child not breastfed within the first hour, and child had consumed milk formula and tea on the first day at home. The following factors were associated with use of artificial nipples (pacifier and bottle feeding: mother working outside the home, primiparity, cesarean delivery, the male gender, low birth weight, born in a hospital not accredited as “baby friendly”, required health baby monitoring in the Primary Health Care Unit (PR = 0.91, and child had consumed milk formula, water, or tea on the first day at home. CONCLUSIONS This study identified profiles of exclusive users of pacifiers, bottle feeding, and both. The provided information can guide preventive practices for child health.

  16. Determinants of using pacifier and bottle feeding.

    Science.gov (United States)

    Buccini, Gabriela dos Santos; Benício, Maria Helena D'Aquino; Venancio, Sonia Isoyama

    2014-08-01

    To analyze the factors associated with the use of pacifiers and/or bottle feeding in infants aged under one year. This is a cross-sectional study with 34,366 children and using data from the database of the 2nd Nationwide Survey of Breastfeeding Prevalence performed in the Brazilian capitals and Federal District in 2008. Cluster sampling was used. The questionnaire included questions about the use of artificial nipples in the last 24 hours. The analysis considered three outcomes: exclusive use of pacifier, exclusive use of bottle feeding, and use of artificial nipples (pacifier and bottle feeding). Prevalence ratios were obtained using Poisson regression with robust variance following a hierarchical model. The following factors were associated with exclusive use of the pacifier: mother working outside the home, primiparity, child was not breastfed within the first hour, and child had consumed tea on the first day at home. The following factors were associated with exclusive use of bottle feeding: mother working outside the home, primiparity, low birth weight, child not breastfed within the first hour, and child had consumed milk formula and tea on the first day at home. The following factors were associated with use of artificial nipples (pacifier and bottle feeding): mother working outside the home, primiparity, cesarean delivery, the male gender, low birth weight, born in a hospital not accredited as "baby friendly", required health baby monitoring in the Primary Health Care Unit (PR = 0.91), and child had consumed milk formula, water, or tea on the first day at home. This study identified profiles of exclusive users of pacifiers, bottle feeding, and both. The provided information can guide preventive practices for child health.

  17. Bromate pollutant in ozonated bottled Zamzam water from Saudi Arabia determined by LC/ICP-MS.

    Science.gov (United States)

    Al-Ansi, Seham A; Othman, Ahmed A; Al-Tufail, Mohammed A

    2011-01-01

    Bromate (BrO(3) (-)) as a human carcinogenic pollutant in bottled drinking Zamzam water from Mecca, Saudi Arabia has been determined using liquid chromatography inductively coupled plasma mass spectrometry (LC/ICP-MS). For analysis, samples were injected directly without any further pretreatment, using only 50 μL injection volume. The method showed: 0.5 μg/L detection limit, 1.0 μg/L limit of quantification and 1.0-200.0 μg/L linearity range (r(2) = 0.9998). The relative standard deviation (%RSD) values for reproducibility (interday precision) obtained are at 11 % and 14 % for bromate and bromide at low concentration levels (5, 10 μg/L) and at 4 % for both at high concentration levels (50, 100 μg/L), respectively. The results concluded that the ozonated bottled Zamzam water samples are contaminated with bromate. The concentration is 20 times higher than U.S. Environmental Protection Agency (U.S. EPA) allowable limit (10 μg/L) for bromate in bottled drinking water. Bottled drinking water brands, disinfected with ozone showed relatively lower levels of bromate as compared with Zamzam water.

  18. Water bottle rocket in undergraduate laboratory

    Science.gov (United States)

    Schultz, William

    2012-11-01

    In the winter semester of 2012, we implemented the modeling and testing of a water bottle rocket in ME 495, the Senior Laboratory in Mechanical Engineering at the University of Michigan. The four week lab was the most well received by the students in recent memory. There were significant challenges, but the result was a thorough review of their undergraduate fluids class with some advanced concepts such as directional stability of a projectile. The student teams designed their own rockets based on one of many standard 20 ounce soft drink bottles. The culminating contest brought impressive results and a surprise ending.

  19. Interfacial properties of bottle-brush polyelectrolytes

    DEFF Research Database (Denmark)

    Claesson, P. M.; Naderi, A.; Iruthayaraj, J.

    2007-01-01

    This article is focused on interfacial properties of bottle brush polyelectrolytes, where side-chains are attached along a polymer backbone. This class of polymer has been much less studied than block copolymers, which is particularly true for bottle brush polyelectrolytes with a high graft density...... whereas on silica both electrostatic forces and interactions between silica and ethylene oxide chains drive the adsorption. On silica the adsorbed amount is very sensitive to solution ionic strength and pH. We also report on surface interactions and frictional forces obtained between surfaces coated...

  20. Bottle wars: England versus Scotland versus France.

    Science.gov (United States)

    Thurman, Robert B; Athanasopoulos, Athanassios A; Allan, Michael S; Atchia, Sarah M

    2002-05-01

    Four batches of four brands of bottled water from England, Scotland and France were tested for their microbiological and physicochemical characteristics during a 2-month study. The lowest priced brand of water had the highest nitrate content (46.9 mg/L), while the most expensive brand did not necessarily have the best values for pH, total dissolved solids, turbidity or plate count. While no sample was positive for E. coli, the range of other measured values varied widely between brands and batches during the study. The bottled water samples from France on average demonstrated better results than the other countries studied.

  1. Temporal responses of cutaneous blood flow and plasma catecholamine concentrations to histamine H1- or H2-receptor stimulation in man

    DEFF Research Database (Denmark)

    Knigge, U; Alsbjørn, B; Thuesen, B

    1988-01-01

    We have studied the effect of histamine and H1- or H2-receptor antagonists on cutaneous blood flow and catecholamine release in man. Histamine was infused alone or in combination with mepyramine, an H1-antagonist or cimetidine, an H2-antagonist for 2 h. Cutaneous blood flow was measured continuou......We have studied the effect of histamine and H1- or H2-receptor antagonists on cutaneous blood flow and catecholamine release in man. Histamine was infused alone or in combination with mepyramine, an H1-antagonist or cimetidine, an H2-antagonist for 2 h. Cutaneous blood flow was measured...... that histamine causes an immediate cutaneous vasodilatation through H1-receptors and a more sustained response through H2-receptors. The vasodilatation is accompanied by an increase in plasma catecholamine concentrations. Despite the continuous infusion of histamine, blood flow decreased during the last hour...

  2. Bottle-feeding and the Risk of Pyloric Stenosis

    DEFF Research Database (Denmark)

    Krogh, Camilla; Biggar, Robert J; Fischer, Thea Kølsen

    2012-01-01

    Bottle-feeding has been suggested to increase the risk of pyloric stenosis (PS). However, large population-based studies are needed. We examined the effect of bottle-feeding during the first 4 months after birth, by using detailed data about the timing of first exposure to bottle-feeding...

  3. factors influencing the consumption and standards of bottled ...

    African Journals Online (AJOL)

    BARTH EKWUEME

    the need to stay hydrated and the greater accessibility of bottled water in emerging economies. Bottled water remains a soft drink force to be reckoned with (Zenith. International, 2006). Bottled water companies such as. Dasani, Nestle, Coca-Cola and Pepsi are engaged in constant search for new water supplies to feed the.

  4. A fluid sample bottle for use in deep wells

    Energy Technology Data Exchange (ETDEWEB)

    Duvallet, B.

    1991-11-15

    A new sample bottle for collecting mixtures of water and gas in deep wells is presented. The bottle, where vacuum is realized beforehand, is filled with a filtration system for solid particles. Pure water and gas may be delivered separately. The bottle is applicable to geothermics, nuclear plants, oceanography and geochemistry.

  5. Prospects for Recycling of Waste PET Bottles in Mauritius

    African Journals Online (AJOL)

    Nafiisah

    This paper analyses the status and prospects of waste PET (PolyEthylene. Terephthalate) bottles recycling in Mauritius. Over the past decade the packaging industry has witnessed a momentous swing away from glass bottles and cans into fully recyclable PET plastic bottles, being viewed as a more consumer friendly.

  6. Buying and Caring for Baby Bottles and Nipples

    Science.gov (United States)

    ... will not break if dropped. If you choose plastic, it is best to buy new bottles. Reused or hand-me-down bottles may contain bisphenol-A (BPA). The Food and Drug Administration (FDA) has banned the use of BPA in baby bottles due ...

  7. 27 CFR 24.255 - Bottling or packing wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bottling or packing wine..., DEPARTMENT OF THE TREASURY LIQUORS WINE Storage, Treatment and Finishing of Wine Bottling, Packing, and Labeling of Wine § 24.255 Bottling or packing wine. (a) General. Proprietors of a bonded wine premises and...

  8. Flow

    DEFF Research Database (Denmark)

    Knoop, Hans Henrik

    2006-01-01

    FLOW. Orden i hovedet på den fede måde Oplevelsesmæssigt er flow-tilstanden kendetegnet ved at man er fuldstændig involveret, fokuseret og koncentreret; at man oplever stor indre klarhed ved at vide hvad der skal gøres, og i hvilket omfang det lykkes; at man ved at det er muligt at løse opgaven...

  9. Development and Evaluation of an Externally Air-Cooled Low-Flow torch and the Attenuation of Space Charge and Matrix Effects in Inductively Coupled Plasma Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Praphairaksit, Narong [Iowa State Univ., Ames, IA (United States)

    2000-09-12

    An externally air-cooled low-flow torch has been constructed and successfully demonstrated for applications in inductively coupled plasma mass spectrometry (ICP-MS). The torch is cooled by pressurized air flowing at ~70 L/min through a quartz air jacket onto the exterior of the outer tube. The outer gas flow rate and operating RF forward power are reduced considerably. Although plasmas can be sustained at the operating power as low as 400 W with a 2 L/min of outer gas flow, somewhat higher power and outer gas flows are advisable. A stable and analytical useful plasma can be obtained at 850 W with an outer gas flow rate of ~4 L/min. Under these conditions, the air-cooled plasma produces comparable sensitivities, doubly charged ion ratios, matrix effects and other analytical merits as those produced by a conventional torch while using significantly less argon and power requirements. Metal oxide ion ratios are slightly higher with the air-cooled plasma but can be mitigated by reducing the aerosol gas flow rate slightly with only minor sacrifice in analyte sensitivity. A methodology to alleviate the space charge and matrix effects in ICP-MS has been developed. A supplemental electron source adapted from a conventional electron impact ionizer is added to the base of the skimmer. Electrons supplied from this source downstream of the skimmer with suitable amount and energy can neutralize the positive ions in the beam extracted from the plasma and diminish the space charge repulsion between them. As a result, the overall ion transmission efficiency and consequent analyte ion sensitivities are significantly improved while other important analytical aspects, such as metal oxide ion ratio, doubly charged ion ratio and background ions remain relatively unchanged with the operation of this electron source. This technique not only improves the ion transmission efficiency but also minimizes the matrix effects drastically. The matrix-induced suppression of signal for even the most

  10. Asymmetrical flow field-flow fractionation coupled to inductively coupled plasma mass spectrometry for sizing SeNPs for packaging applications

    Science.gov (United States)

    Palomo-Siguero, María; Vera, Paula; Echegoyen, Yolanda; Nerin, Cristina; Cámara, Carmen; Madrid, Yolanda

    2017-06-01

    This paper describes the application of Asymmetrical Flow Field-Flow Fractionation (AF4) coupled to diode array detector (DAD) and inductively coupled plasma mass spectrometry (AF4-UV-ICP-MS) to characterize selenium nanoparticles (SeNPs) in an aqueous acrylic adhesive to be used in a multilayer food packaging material. SeNPs were synthesized using a solution-phase approach based on the reduction of selenite with ascorbic acid in presence of different stabilizers compatible with food industry such as polysaccharides (chitosan (poly(D-glucosamine) and hydroxyethylcellulose (HEC)) and non-ionic surfactants (Triton X-100 (t-octylphenoxypolyethoxyethanol), 2,4,7,9-tetramethyl 5decyne-4,7-diol ethoxylate, and isotridecanol ethoxylate). Several parameters such as pH, ascorbic acid and stabilizers concentration, and compatibility of the stabilizer with the adhesive were evaluated. SeNPs suspensions with spherical morphology were obtained except when isotridecanol ethoxylate was employed which provides SeNPs with a nanorod morphology. AF4-DAD-ICP-MS was further applied for sizing the different SeNPs preparations. DAD was used as detector for selecting the best AF4 separation conditions before coupling to ICP-MS to ensure unequivocal identification of NPs. AF4 calibration with polystyrene latex (PSL) beads of known sizes allowed size determination of the different SeNPs. The following estimated hydrodynamic sizes (expressed as the mean ± standard deviation, n = 6 replicates) were found: chitosan-SeNPs- (26 ± 3 nm), TritonX100-SeNPs (22 ± 10 nm) HEC- SeNPs (91 ± 8 nm) and 2,4,7,9-tetramethyl 5decyne-4,7-diol ethoxylate- SeNPs (59 ± 4 nm). The proposed methodology was successfully applied to the characterization in terms of size of aqueous acrylic adhesives containing SeNPs Results from AF4-ICP-MS and TEM shown that only those SeNPs obtained with non-ionic surfactants and HEC were compatible with the adhesive. The results reported here evidence the usefulness of AF4-ICP

  11. Plastic Bottles Waste Utilization as Modifier for Asphalt Mixture Production

    Directory of Open Access Journals (Sweden)

    Jan Hakeem

    2017-01-01

    Full Text Available Plastic Bottles was used as the polymeric waste to investigate performance of asphalt mixture Aggregates obtained from Margalla, Burhan and Karak quarries. 12 samples were prepared for conventional asphalt mixtures and 48 samples were prepared for PB modified asphalt mixture of each quarries at various proportions of PB waste. The PB used for modification according to wet process are 15%, 20%, 25% and 30% by weight of Optimum Bitumen Content (OBC. OBC of 4.2 % was concluded for conventional asphalt mixtures. The stability and flow values of the conventional and modified Asphalt Mixture were compared. The average Stability of the modified Margalla asphalt mixtures when 15% PB was used was much higher as compared to conventional asphalt mixtures. But when PB was used beyond 15%, the Marshall stability showed a decreasing trend for Margalla aggregates, increasing trend for Karak aggregates and decreasing trend for Burhan aggregates. This decline in stability is attributed to a decline in interlocking of aggregates due to lubricating effect. The corresponding flow for the Modified asphalt mixtures first showed a decreasing trend for Margalla aggregates at 15% PB modification but beyond 15%, an increasing trend in flow as compared to conventional asphalt mixtures The decrease in flow or increase in Marshall Stability is attributed to improvement in interlocking and decline in flow or stability is attributed to a decline in interlocking offered by binder and PB coated aggregate particles in modified asphalt.

  12. Green Fiber Bottle:the fully biodegradable packaging

    OpenAIRE

    Didone, Mattia; Tosello, Guido

    2016-01-01

    The ambition of the Green Fiber Bottle (GFB) project is to manufacture a fully biodegradable bottle. Carlsberg is the intended end user, and they aim to package their beer in the new bottle. The new product is intended to replace the existing plastic and glass bottles, and thus reducing their impact on the environment, especially the oceans. For example, the life span of a plastic bottle in the ocean is 500 years, and during its degradation, the plastic is reduced to micro pieces, which cause...

  13. Bottle microresonator with actively stabilized evanescent coupling

    NARCIS (Netherlands)

    Junge, C.; Nickel, S.; O'Shea, D.; Rauschenbeutel, A.

    2011-01-01

    The evanescent coupling of light between a whispering-gallery-mode bottle microresonator and a subwavelength-diameter coupling fiber is actively stabilized by means of the Pound-Drever-Hall technique. We demonstrate the stabilization of a critically coupled resonator with a control bandwidth of 0.1

  14. Bottled Water Everywhere: Keeping it Safe

    Science.gov (United States)

    ... water also comes from municipal sources—in other words, the tap. Municipal water is usually treated before it is bottled. Examples ... regulations put in place and enforced by FDA. Water must be sampled, analyzed, and found to be safe and sanitary. These regulations also ...

  15. Ralstonia pickettii Traced in Blood Culture Bottles

    OpenAIRE

    Boutros, Névine; Gonullu, Nevriye; Casetta, Anne; Guibert, Michèle; Ingrand, Didier; Lebrun, Léa

    2002-01-01

    Over a 9-month period, 14 strains of Ralstonia pickettii were isolated from various biological samples inoculated in a blood culture medium. Molecular epidemiological investigation confirmed the relatedness of the strains. The source of the contamination proved to be the blood culture bottle caps.

  16. Legionella pneumophila in commercial bottled mineral water.

    NARCIS (Netherlands)

    Klont, R.R.; Rijs, A.J.M.M.; Warris, A.; Sturm, P.D.J.; Melchers, W.J.G.; Verweij, P.E.

    2006-01-01

    Sixty-eight commercial bottled mineral waters (64 brands, 68 different 'best-before dates') were tested for the presence of bacteria and fungi. Six samples were Legionella antigen positive and six were Legionella pneumophila PCR positive. Two samples were both Legionella antigen and L. pneumophila

  17. Automation of a mass flow controller for application in time-multiplex SF{sub 6}+CH{sub 4} plasma etching of silicon

    Energy Technology Data Exchange (ETDEWEB)

    Tezani, L.L.; Moraes, R.S.; Medeiros, H.S.; Petraconi Filho, G.; Massi, M.; Silva Sobrinho, A.S. da [Laboratorio de Plasmas e Processos, Instituto Tecnologico de Aeronautica, 12228-900, Sao Jose dos Campos-SP (Brazil); Pessoa, R.S.; Maciel, H.S. [Laboratorio de Plasmas e Processos, Instituto Tecnologico de Aeronautica, 12228-900, Sao Jose dos Campos-SP (Brazil); IP and D, Universidade do Vale do Paraiba, 12244-000, Sao Jose dos Campos-SP (Brazil); Martins, C.A. [Laboratorio de Combustao, Propulsao e Energia, Instituto Tecnologico de Aeronautica, 12228-900, Sao Jos dos Campos-SP (Brazil)

    2012-10-15

    In this work is proposed the automation of a gas injection (mass flow) system in order to generate timemultiplex SF{sub 6}/CH{sub 4} radiofrequency plasma applied for silicon (Si) etching process. The control of the gas injection system is important in order to better control the process anisotropy, i.e., the high-aspect-ratio of mask pattern transfer to substrate surface. In other words, this control allows the attainment of deep Si etching process. Here, the automation of the gas injection system was realized through the interface between a computer and a data acquisition board. The automation software developed allows controlling the gas flow rate switching it on and off during whole process through the use of a square waveform routine, intermittent flow, beyond the conventional condition of a fixed value for gas flow rate, continuous flow. In order to investigate the time-multiplex SF{sub 6}/CH{sub 4} plasma etching of Si, the residual gas analysis was performed. The investigations were made keeping the following process parameters: flow of SF{sub 6}: 10 sccm, flow of CH{sub 4}: 6 sccm, 100 W rf power, wave period: 20 sec. It were monitored the partial pressure of SF{sup +} {sub 5} (parent neutral specie: SF{sub 6}), CH{sup +}{sub 4} (CH4) and SiF+{sub 3} (SiF4) species as a function of time for different gas flow switching and duty cycle. The results showed that with the generation of plasma occurs a drastic change in behavior of partial pressures of SF{sup +} {sub 5} and CH{sup +}{sub 4} species. Moreover, it is evidenced that the interactions between the SF{sub 6} and CH{sub 4} fragments promotes a high production rate of HF molecule and consequently a decrease of atomic fluorine, mainly when plasma is on. Finally, the behavior of partial pressure of SiF{sup +} {sub 3} specie for alternatively intermittent SF{sub 6} and CH{sub 4} flow operation shows us that both the etching processes and the deposition of a polymer passivation layer are occurring

  18. Development of Energy Efficient, Multi-Channel, Pulsed Plasma Generator for High-Speed Flow Control by Localized Arc Filament Plasma Actuators Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The research team at The Ohio State University has been developing technologies to suppress jet noise using localized arc filament plasma actuators and are in the...

  19. Pressure and energy balance of stagnating plasmas in z-pinch experiments: implications to current flow at stagnation.

    Science.gov (United States)

    Maron, Y; Starobinets, A; Fisher, V I; Kroupp, E; Osin, D; Fisher, A; Deeney, C; Coverdale, C A; Lepell, P D; Yu, E P; Jennings, C; Cuneo, M E; Herrmann, M C; Porter, J L; Mehlhorn, T A; Apruzese, J P

    2013-07-19

    Detailed spectroscopic diagnostics of the stagnating plasma in two disparate z pinches allow, for the first time, the examination of the plasma properties within a 1D shock wave picture, demonstrating a good agreement with this picture. The conclusion is that for a wide range of imploding-plasma masses and current amplitudes, in experiments optimizing non-Planckian hard radiation yields, contrary to previous descriptions the stagnating plasma pressure is balanced by the implosion pressure, and the radiation energy is provided by the imploding-plasma kinetic energy, rather than by the magnetic-field pressure and magnetic-field-energy dissipation, respectively.

  20. Bottle-feeding and the Risk of Pyloric Stenosis.

    Science.gov (United States)

    Krogh, Camilla; Biggar, Robert J; Fischer, Thea K; Lindholm, Morten; Wohlfahrt, Jan; Melbye, Mads

    2012-10-01

    Bottle-feeding has been suggested to increase the risk of pyloric stenosis (PS). However, large population-based studies are needed. We examined the effect of bottle-feeding during the first 4 months after birth, by using detailed data about the timing of first exposure to bottle-feeding and extensive confounder information. We performed a large population-based cohort study based on the Danish National Birth Cohort, which provided information on infants and feeding practice. Information about surgery for PS was obtained from the Danish National Patient Register. The association between bottle-feeding and the risk of PS was evaluated by hazard ratios (HRs) estimated in a Cox regression model, adjusting for possible confounders. Among 70148 singleton infants, 65 infants had surgery for PS, of which 29 were bottle-fed before PS diagnosis. The overall HR of PS for bottle-fed infants compared with not bottle-fed infants was 4.62 (95% confidence interval [CI]: 2.78-7.65). Among bottle-fed infants, risk increases were similar for infants both breast and bottle-fed (HR: 3.36 [95% CI: 1.60-7.03]), formerly breastfed (HR: 5.38 [95% CI: 2.88-10.06]), and never breastfed (HR: 6.32 [95% CI: 2.45-16.26]) (P = .76). The increased risk of PS among bottle-fed infants was observed even after 30 days since first exposure to bottle-feeding and did not vary with age at first exposure to bottle-feeding. Bottle-fed infants experienced a 4.6-fold higher risk of PS compared with infants who were not bottle-fed. The result adds to the evidence supporting the advantage of exclusive breastfeeding in the first months after birth.

  1. Clinical Comparison of Nonvented Aerobic BacT/Alert Blood Culture Bottle and Standard Aerobic Bottle for Detection of Microorganisms in Blood

    Science.gov (United States)

    Snyder, James W.; Benzing, Karen S.; Munier, Gina K.; Bostic, Grace D.; Bozigar, Pamela S.; Hanna, Rami; Zervos, Marcus J.

    2000-01-01

    The current BacT/Alert standard aerobic (VA) blood culture bottle was redesigned and designated a nonvented aerobic (NVA) culture bottle; this bottle does not require venting. A total of 3,873 sets of blood samples for culture were obtained from adult patients with suspected bacteremia or fungemia. The NVA bottle showed performance equivalent to that of the VA bottle for recovery and speed of detection of microorganisms from blood without the need for venting the bottle. PMID:11015422

  2. Voltage and Pressure Scaling of Streamer Dynamics in a Helium Plasma Jet With N2 CO-Flow (Postprint)

    Science.gov (United States)

    2014-08-14

    annular co- flow gas into the helium core flow can be neglected at positions approximately up to 33...diffusional mixing layer of the annular co- flow N2 for the conditions shown in Figure 7. Thus, it is unlikely that both the core - flow helium and annular ...directed streamer propagation in helium flow channel with N2 annular co- flow compared to the streamer propagation in air or nitrogen have been

  3. An upright eyedrop bottle: accuracy, usage of excess drops, and contamination compared to a conventional bottle

    Directory of Open Access Journals (Sweden)

    Davies IJ

    2016-07-01

    Full Text Available Isaiah J Davies,1 Ninita H Brown,2 Joanne C Wen,3 Sandra S Stinnett,1 Kelsey Kubelick,4,5 Roma P Patel,6 Kristin L Benokraitis,7 Latoya Greene,1 Curry Cheek,1 Kelly W Muir1,8 1Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA; 2Metrolina Eye Associates, Charlotte, NC, USA; 3Department of Ophthalmology, University of Washington, Seattle, WA, USA; 4Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 5Wallace H Coulter Department of Biomedical Engineering, Emory University School of Medicine, Atlanta, Georgia, USA; 6University of California Davis Health System Eye Center, Sacramento, CA, USA; 7EG-GILERO, Durham, NC, USA; 8Health Services Research & Development, Durham VA Medical Center, Durham, NC, USA Purpose: This study tested the feasibility of using an upright eyedrop bottle (UEB, a device designed to assist patients with eyedrop placement without reclining their head. Patients and methods: Experienced eyedrop users were enrolled who answered “yes” to the question, “Do you ever have trouble getting your eyedrops in?” After being shown a multimedia presentation and answering a questionnaire regarding eyedrop usage, participants were observed instilling eyedrops. Participants were instructed to instill a single eyedrop in each eye with both a standard bottle and the UEB. They repeated this process three times. With each trial, the amount of time taken to instill drops was recorded, as well as whether a drop landed in the eye (accuracy, if excess drops were used, and if the bottle tip was contaminated. Results: Forty participants were enrolled, with an average age of 72.4±8.9 years; the majority were females (24 females. Thirty-four participants had been using eyedrops for at least 1 year. The time required to instill eyedrops was significantly less with the UEB in the second and third trials. There was no difference in accuracy between the conventional bottle and the UEB

  4. High Plasma Levels of Neuropeptide Y Correlate With Good Clinical Outcome But are not Correlated to Cerebral Blood Flow or Vasospasm After Subarachnoid Hemorrhage

    DEFF Research Database (Denmark)

    Rasmussen, Rune; Stavngaard, Trine; Jessing, Iben R

    2016-01-01

    and a role of NPY in the development of DCI has been proposed. This study investigated the relationship between plasma-NPY and cerebral blood flow (CBF), cerebral vasospasm, DCI, and clinical outcome. METHODS: In 90 patients with subarachnoid hemorrhage, NPY was measured in peripheral blood days 2 to 11. Any...... reduced plasma-NPY and DCI reached borderline statistical significance (P=0.05). Increased levels of NPY measured on days 2 to 4 were correlated to good outcome (P=0.006). CONCLUSIONS: Our findings in peripheral blood were not supportive of a causal relationship between NPY secretion and DCI. Although...... high levels of plasma-NPY were correlated with good clinical outcome, NPY did not show promise as a clinically useful biomarker....

  5. A lateral flow immunoassay for rapid evaluation of vitellogenin levels in plasma and surface mucus of the copper redhorse (Moxostoma hubbsi).

    Science.gov (United States)

    Maltais, Domynick; Roy, Robert L

    2007-08-01

    We tested a lateral flow immunoassay (LFIA) for detecting vitellogenin (VTG) in plasma and surface mucus of copper redhorse, Moxostoma hubbsi, a threatened fish species. The LFIA detected VTG in samples from estradiol-induced fish, though there was no reaction in samples from noninduced individuals. The minimum detection range was 0.08 to 0.60 microg VTG/ml, comparable to other methods. The LFIA has the potential to detect exposure to estrogenic endocrine-disrupting chemicals.

  6. Minimal residual disease-based risk stratification in Chinese childhood acute lymphoblastic leukemia by flow cytometry and plasma DNA quantitative polymerase chain reaction.

    Directory of Open Access Journals (Sweden)

    Suk Hang Cheng

    Full Text Available Minimal residual disease, or MRD, is an important prognostic indicator in childhood acute lymphoblastic leukemia. In ALL-IC-BFM 2002 study, we employed a standardized method of flow cytometry MRD monitoring for multiple centers internationally using uniformed gating, and determined the relevant MRD-based risk stratification strategies in our local patient cohort. We also evaluated a novel method of PCR MRD quantitation using peripheral blood plasma. For the bone marrow flow MRD study, patients could be stratified into 3 risk groups according to MRD level using a single time-point at day-15 (Model I (I-A: 10%, or using two time-points at day-15 and day-33 (Model II (II-A: day-15<10% and day-33<0.01%, II-B: day-15 ≥ 10% or day-33 ≥ 0.01% but not both, II-C: day-15 ≥ 10% and day-33 ≥ 0.01%, which showed significantly superior prediction of relapse (p = .00047 and <0.0001 respectively. Importantly, patients with good outcome (frequency: 56.0%, event-free survival: 90.1% could be more accurately predicted by Model II. In peripheral blood plasma PCR MRD investigation, patients with day-15-MRD ≥ 10(-4 were at a significantly higher risk of relapse (p = 0.0117. By multivariate analysis, MRD results from both methods could independently predict patients' prognosis, with 20-35-fold increase in risk of relapse for flow MRD I-C and II-C respectively, and 5.8-fold for patients having plasma MRD of ≥ 10(-4. We confirmed that MRD detection by flow cytometry is useful for prognostic evaluation in our Chinese cohort of childhood ALL after treatment. Moreover, peripheral blood plasma DNA MRD can be an alternative where bone marrow specimen is unavailable and as a less invasive method, which allows close monitoring.

  7. Effects of whole blood viscosity and plasma NOx on cardiac function and cerebral blood flow in children with chronic kidney disease

    Science.gov (United States)

    Buyan, Necla; Akçaboy, Meltem; Göktaş, Tayfun; Kula, Serdar; Nazlıel, Bijen; Çakar, Nilgün; Uncu, Nermin; Çelik, Bülent; Erbaş, Deniz

    2017-11-13

    Background/aim: The aim of the study was to investigate the effects of whole blood viscosity and plasma nitric oxide on cerebral and cardiovascular risks associated with chronic kidney disease. Materials and methods: The study group consisted of 40 pediatric patients and 21 healthy control subjects. Hematologic and biochemical variables, viscosity and plasma nitric oxide levels, echocardiographic findings, and middle cerebral artery blood flow velocity were examined. Results: Viscosity values of patients were significantly lower than those of the control group. Lower values of hematocrit, total protein, and albumin and higher values of ferritin in all patient groups resulted in significantly low viscosity levels. Plasma nitric oxide levels were higher in all patient groups than those in the controls. No statistically significant difference was present in middle cerebral artery blood flow velocity between the patient and control groups. Even when systolic functions were normal, the patient group had significant deterioration in diastolic functions, suggesting morbidity and mortality risks. Conclusions: Cerebral blood flow velocities were not affected by viscosity and nitric oxide levels, suggesting that cerebral circulation has the ability to make adaptive modulation. The metabolism of nitric oxide levels needs further investigation and studies in patients with chronic renal disease.

  8. O2(1Δ) production in He/O2 mixtures in flowing low pressure plasmas

    Science.gov (United States)

    Stafford, D. Shane; Kushner, Mark J.

    2004-09-01

    Chemical oxygen-iodine lasers (COIL) are attractive for diverse industrial applications because they are capable of high efficiency, high power operation, and because the 1.315μm wavelength can be transmitted through fiber optics and couples efficiently with most metals. Conventional COILs are pumped with O2(Δ1) that is generated by reaction of Cl2 in a basic H2O2 solution. Current trends in pumping COILs involve producing the O2(Δ1) in electric discharges, thereby circumventing the hazards, complexity, and weight associated with pumping and storing caustic liquids. In this work, we have investigated the scaling of O2(Δ1) yields with specific energy deposition in He /O2 mixtures in flowing radio frequency (rf) discharges at pressures of a few to tens of Torr using a global plasma kinetics model. We found that O2(Δ1) yield increases nearly linearly with specific energy deposition in O2 molecules up to a few eV per molecule, with yields peaking around 30% by 5-8eV. Further increases in specific energy deposition serve only to increase O2 dissociation and gas heating, thereby reducing the O2(Δ1) yield. We also found that variations in peak yields at a given specific energy deposition are caused by secondary effects resulting from dilution, pressure, and power level. We show that these secondary effects alter the O2(Δ1) yield by shifting the O2(Σ1)/O2(Δ1) ratio.

  9. A new approach to determine the susceptibility of bacteria to antibiotics directly from positive blood culture bottles in two hours.

    Science.gov (United States)

    March, Gabriel A; García-Loygorri, María C; Simarro, María; Gutiérrez, María P; Orduña, Antonio; Bratos, Miguel A

    2015-02-01

    The rapid identification and antibiotic susceptibility test of bacteria causing bloodstream infections are given a very high priority by clinical laboratories. In an effort to reduce the time required for performing antibiotic susceptibility test (AST), we have developed a new method to be applied from positive blood culture bottles. The design of method was performed using blood culture bottles prepared artificially with five strains which have a known susceptibility. An aliquot of the blood culture was subcultured in the presence of specific antibiotics and bacterial counts were monitored using the Sysmex UF-1000i flow cytometer at different times up to 180min. Receiver operating curve (ROC) analysis allowed us to find out the cut-off point for differentiating between sensitive and resistant strains to the tested antibiotic. This procedure was then validated against standard commercial methods on a total of 100 positive blood culture bottles from patients. First, bacterial identification was performed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) directly from positive blood culture bottles as we have previously reported. Secondly, antibiotic susceptibility test was performed in the same way that was carried out in artificially prepared blood culture bottles. Our results indicate that antibiotic susceptibility test can be determined as early as 120min since a blood culture bottle is flagged as positive. The essential agreement between our susceptibility test and commercial methods (E-test, MicroScan and Vitek) was 99%. In summary, we conclude that reliable results on bacterial identification and antibiotic susceptibility test performed directly from positive blood culture bottles can be obtained within 3h. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Health beliefs about bottled water: a qualitative study

    Directory of Open Access Journals (Sweden)

    Wernham Aaron GH

    2009-06-01

    Full Text Available Abstract Background There has been a consistent rise in bottled water consumption over the last decade. Little is known about the health beliefs held by the general public about bottled water as this issue is not addressed by the existing quantitative literature. The purpose of this study was to improve understanding of the public's health beliefs concerning bottled mineral water, and the extent to which these beliefs and other views they hold, influence drinking habits. Methods A qualitative study using semi-structured interviews, with 23 users of the Munrow Sports Centre on the University of Birmingham campus. Results Health beliefs about bottled water could be classified as general or specific beliefs. Most participants believed that bottled water conferred general health benefits but were unsure as to the nature of these. In terms of specific health beliefs, the idea that the minerals in bottled water conferred a health benefit was the most commonly cited. There were concerns over links between the plastic bottle itself and cancer. Participants believed that bottled water has a detrimental effect on the environment. Convenience, cost and taste were influential factors when making decisions as to whether to buy bottled water; health beliefs were unimportant motivating factors. Conclusion The majority of participants believed that bottled water has some health benefits. However, these beliefs played a minor role in determining bottled water consumption and are unlikely to be helpful in explaining recent trends in bottled water consumption if generalised to the UK population. The health beliefs elicited were supported by scientific evidence to varying extents. Most participants did not feel that bottled water conferred significant, if any, health benefits over tap water.

  11. Decay of enhanced density and damping of plasma flows after the electrode biasing terminaton on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Hron, Martin; Ďuran, Ivan; Stöckel, Jan; Hidalgo, C.

    2004-01-01

    Roč. 54, suppl. C (2004), C22-C27 ISSN 0011-4626. [Symposium on Plasma Physics and Technology /21st/. Praha, 14.06.2004-17.06.2004] R&D Projects: GA ČR GA202/03/0786 Institutional research plan: CEZ:AV0Z2043910 Keywords : tokamak, edge plasma, polarization Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.292, year: 2004

  12. [Fundamental studies with respect to plasma exchange by using continuous-flow centrifuge system and the clinical trial in patients with myasthenia gravis].

    Science.gov (United States)

    Suga, M; Akahonai, Y; Tsujisaki, M; Mori, M; Yoshizaki, H; Matsumoto, H; Yachi, A

    1982-11-01

    A plasma exchange by using the continuous-flow centrifuge blood cell separator (IBM 2997) was carried out in 13 patients with various diseases including myasthenia gravis. The effects of the plasma exchange on blood components and side effects during the procedure were evaluated. In addition, 5 cases with severe myasthenia gravis who had failed to respond to medication were treated by plasma exchange, and the results were as follows: 1. Red blood cells, hemoglobin and hematocrit levels were significantly decreased while white blood cells inclined to increase after plasma exchange. In serum electrolytes and proteins there were no changes. 2. The side effects such as itching and eruption were observed in 46% of the patients. However, they disappeared within a short period. 3. In 2 cases with myasthenia gravis, a significant improvement in muscle weakness was observed by plasma exchange. In these cases, serum levels of the acetylcholine receptor antibody and the circulating immune complex were decreased, as compared with the previous levels. These parameters showed no correlation with severity of the disease.

  13. Simultaneous photometric determination of albumin and total protein in animal blood plasma employing a multicommutated flow system to carried out on line dilution and reagents solutions handling

    Science.gov (United States)

    Luca, Gilmara C.; Reis, Boaventura F.

    2004-02-01

    An automatic flow procedure for the simultaneous determination of albumin and total protein in blood plasma samples is proposed. The flow network comprised a set of three-way solenoid valves assembled to implement the multicommutation. The flow set up was controlled by means of a computer equipped with an electronic interface card which running a software wrote in QUICKBASIC 4.5 performed on line programmed dilution to allow the determination of both albumin and total protein in blood plasma. The photometric methods based on Bromocresol Green and Biuret reagents were selected for determination of albumin and total protein, respectively. Two LEDs based photometers coupled together the flow cells were employed as detector. After the adjustment of the operational parameters the proposed system presented the following features: an analytical throughput of 45 sample processing per hour for two analytes; relative standard deviations of 1.5 and 0.8% ( n=10) for a typical sample presenting 34 g l -1 albumin and 90 g l -1 total protein, respectively; linear responses ranging from 0 to 15 g l -1 albumin ( r=0.998) and total protein ( r=0.999); sample and reagents consumption, 140 μl serum solution, 0.015 mg VBC and 0.432 mg CuSO 4 per determination, respectively. Applying the paired t-test between results obtained using the proposed system and reference methods no significant difference at 95 and 90% confidence level for albumin and total protein, respectively, were observed.

  14. Effect of disodium cromoglycate (DSCG) and antihistamines on post-irradiation cerebral blood flow and plasma levels of histamine and neurotensin

    Energy Technology Data Exchange (ETDEWEB)

    Cockerham, L.G.; Pautler, E.L.; Carraway, R.E.; Cochrane, D.E.; Hampton, J.D.

    1988-01-01

    In an attempt to elucidate mechanisms underlying the irradiation-induced decrease in regional cerebral blood flow (rCBF) in primates, hippocampal and visual cortical blood flows of rhesus monkeys were measured by hydrogen clearance, before and after exposure to 100-Gy, whole-body, gamma irradiation. Systemic blood pressures were monitored simultaneously. Systemic arterial plasma histamine and neurotensin levels were determined preirradiation and postirradiation. Compared to control animals, the irradiated monkeys exhibited an abrupt decline in systemic blood pressure to 23% of the preirradiation level within 10-min postirradiation, falling to 12% by 60 min. A decrease in hippocampal blood flow to 32% of the preirradiation level was noted at 10-min postirradiation, followed by a slight recovery to 43% at 30 min and a decline to 23% by 60 min. The cortical blood flow for the same animals showed a steady decrease to 29% of the preirradiation levels by 60-min postirradiation. Animals given the mast-cell stabilizer disodium cromoglycate and the antihistamines mepyramine and cimetidine before irradiation did not exhibit an abrupt decline in blood pressure but displayed a gradual decrease to a level 33% below preirradiation levels by 60 min postirradiation. Also, the treated, irradiated monkeys displayed rCBF values that were not significantly different from the nonirradiated controls. The plasma neurotensin levels in the irradiated animals, treated and untreated, indicated a nonsignificant postirradiation increase above control levels.

  15. Kaleidoscope – Printed Textiles by Neil Bottle

    OpenAIRE

    Bottle, Neil

    2013-01-01

    One man show at Rochester Art Gallery. In the Kaleidoscope series, Neil Bottle explores the relationship between digital textile printing and craft printing techniques and how these seemingly opposing practices can coexist. A combination of the latest cutting-edge digital print techniques such as dye sublimation combined with craft traditions such as screen printing, discharge printing, pleating and shibori have been developed in the work. The Kaleidoscope series of wallhangings is pr...

  16. Dark Matter in a twisted bottle

    OpenAIRE

    Arbey, Alexandre; Cacciapaglia, Giacomo; Deandrea, Aldo; Kubik, Bogna

    2012-01-01

    The real projective plane is a compact, non-orientable orbifold of Euler characteristic 1 without boundaries, which can be described as a twisted Klein bottle. We shortly review the motivations for choosing such a geometry among all possible two-dimensional orbifolds, while the main part of the study will be devoted to dark matter study and limits in Universal Extra Dimensional (UED) models based on this peculiar geometry. In the following we consider such a UED construction based on the dire...

  17. Bottle microresonator with actively stabilized evanescent coupling

    CERN Document Server

    Junge, C; O'Shea, D; Rauschenbeutel, A

    2011-01-01

    The evanescent coupling of light between a whispering-gallery-mode bottle microresonator and a sub-wavelength-diameter coupling fiber is actively stabilized by means of a Pound-Drever-Hall technique. We demonstrate the stabilization of a critically coupled resonator with a control bandwidth of 0.1 Hz, yielding a residual transmission of (9 \\pm 3) \\times 10^-3 for more than an hour. Simultaneously, the frequency of the resonator mode is actively stabilized.

  18. Recall campaign for gas bottles and banks

    CERN Multimedia

    2015-01-01

    The previous contract with gas supplier Carbagas ended on 31 March 2015. Gas bottles and banks are not a property of CERN. According to the contract terms, they can remain on CERN sites without any extra costs until 30 September 2015.    If you are using Carbagas containers (bottles and/or banks) for gas purchased between 1 April 2010 and 31 March 2015, multiple options exist: Return them to the closest gas point. Purchase them on the following basis:     Rent them on the following basis: 12 CHF/month for bottles, 144 CHF/month for banks. The recall campaign has been going on for several months already: we would like to thank everyone who has already replied to it. If you haven’t answered yet, there is still time. If you know of unused or abandoned Carbagas containers, please don’t hesitate to contact us. Thank you i...

  19. Multicolor flow cytometry and nanoparticle tracking analysis of extracellular vesicles in the plasma of normal pregnant and pre-eclamptic women.

    Science.gov (United States)

    Dragovic, Rebecca A; Southcombe, Jennifer H; Tannetta, Dionne S; Redman, Christopher W G; Sargent, Ian L

    2013-12-01

    Excessive release of syncytiotrophoblast extracellular vesicles (STBMs) from the placenta into the maternal circulation may contribute to the systemic inflammation that is characteristic of pre-eclampsia (PE). Other intravascular cells types (platelets, leukocytes, red blood cells [RBCs], and endothelium) may also be activated and release extracellular vesicles (EVs). We developed a multicolor flow cytometry antibody panel to enumerate and phenotype STBMs in relation to other EVs in plasma from nonpregnant (NonP) and normal pregnant (NormP) women, and women with late-onset PE. Nanoparticle tracking analysis (NTA) was used to determine EV size and concentration. In vitro-derived STBMs and EVs from platelets, leukocytes, RBCs, and endothelial cells were examined to select suitable antibodies to analyze the corresponding plasma EVs. Flow cytometry analysis of plasma from NonP, NormP, and PE showed that STBMs comprised the smallest group of circulating EVs, whereas most were derived from platelets. The next most abundant group comprised unidentified orphan EVs (which did not label with any of the antibodies in the panel), followed by EVs from RBCs and leukocytes. NTA showed that the total number of EVs in plasma was significantly elevated in NormP and late-onset PE women compared to NonP controls, and that EVs were smaller in size. In general, EVs were elevated in pregnancy plasma apart from platelet EVs, which were reduced. These studies did not show any differences in EVs between NormP and PE, probably because late-onset PE was studied.

  20. Quantification of rat retinal and choroidal blood plasma kinetics, volume, and flow in vivo using dynamic contrast optical coherence tomography (Conference Presentation)

    Science.gov (United States)

    Merkle, Conrad W.; Srinivasan, Vivek J.

    2017-02-01

    Blood flow patterns and kinetics in the choriocapillaris are poorly understood owing to a lack of quantitative ophthalmic imaging techniques for studying microvascular flow in the eye. Compared with the proximal retinal vasculature, the more distal choroidal vasculature is relatively more challenging to probe. Magnetic Resonance Imaging and Doppler Ultrasound can assess the retina and choroid, but do not resolve the finer layers or microvasculature. While Optical Coherence Tomography (OCT) angiography produces high-quality choroidal images, attempts at quantification through Doppler-based methods have had mixed success. Here, we use a new technique called Dynamic Contrast OCT (DyC-OCT), which tracks the passage of an intravascular scattering contrast agent, to reveal laminar blood flow patterns in the retina and choroid in vivo. While conceptually similar to fluorescence angiography, DyC-OCT has the substantial benefit of depth resolution, which enables separation of retinal and choroidal microvasculature. The scattering contrast agent enables improved angiography of both macro- and microvasculature in the retina and choroid. Blood plasma transit times are measured in individual vessels, while flow and volume are quantified for each of the microvascular layers. As expected, the choriocapillaris had the highest volume and flow. Blood flow rates were estimated with an average retinal blood flow of 9.1 ± 4.3 μL/min and an average choroidal blood flow of 40 ± 18.3 μL/min in the rat eye. These rates are consistent with previous literature. DyC-OCT affords a new perspective on the poorly understood choriocapillaris blood flow and kinetics and may be useful for studying outer retinal diseases.

  1. Flexural Toughness of Ring-Shaped Waste Bottle Fiber Concrete

    OpenAIRE

    Faisal S. K.; Irwan J.M; Othman N.; Wan Ibrahim M. H.

    2016-01-01

    Polyethylene terephthalate (PET) bottles are plastic containers that are typically discarded, and thus, cause environmental pollution. To solve this problem, PET bottles are recycled incorporating with concrete. A ring-shaped PET (RPET) fiber are introduced in this study and designed with a special shape to mobilize fiber yielding rather than fiber pullout. Therefore, aim of this paper is to investigate the influence of RPET bottles fibre in terms of toughness strength. The width of RPET fibe...

  2. Dispatches from the DMZ: Bottle Cell Formation During Xenopus Gastrulation

    OpenAIRE

    Lee, Jen-Yi

    2011-01-01

    Bottle cell-driven blastopore lip formation externally marks the initiation of gastrulation in amphibian embryos. The blastopore groove is formed when bottle cells undergo apical constriction and transform from cuboidal to flask-shaped. Apical constriction is sufficient to cause invagination and is a highly conserved mechanism for sheet bending and folding during morphogenesis; therefore, studying apical constriction in Xenopus bottle cells could provide valuable insight into this fundamental...

  3. 21 CFR 880.6085 - Hot/cold water bottle.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hot/cold water bottle. 880.6085 Section 880.6085... Devices § 880.6085 Hot/cold water bottle. (a) Identification. A hot/cold water bottle is a device intended for medical purposes that is in the form of a container intended to be filled with hot or cold water...

  4. Nasal continuous positive airway pressure influences bottle-feeding in preterm lambs.

    Science.gov (United States)

    Samson, Nathalie; Michaud, Audrey; Othman, Rahmeh; Nadeau, Charlène; Nault, Stéphanie; Cantin, Danny; Sage, Michaël; Catelin, Céline; Praud, Jean-Paul

    2017-12-01

    BackgroundIn preterm infants, the time from initiation to full oral feeding can take weeks, which represents a very worrisome problem in neonatal medicine. Although current knowledge suggests that oral feeding should be introduced early, this is often delayed due to the need for prolonged nasal continuous positive airway pressure (nCPAP). Indeed, most caregivers fear that nCPAP could disrupt sucking-swallowing-breathing coordination and induce tracheal aspiration. The goal of the present study was to assess the impact of nCPAP delivered by the Infant Flow System on the physiology of sucking-swallowing-breathing coordination during bottle-feeding in preterm lambs over 24 h.MethodsSeventeen lambs (8 control, 9 nCPAP of 6 cmH2O) born 14 days prematurely were instrumented to record sucking, swallowing, respiration, ECG, and oxygenation. They were fed via a nasogastric tube for the first 5 days of life until introduction of bottle-feeding every 4 h for 24 h.ResultsnCPAP increased the feeding efficiency while maintaining higher oxygenation without any deleterious cardiorespiratory events. However, coughs were observed in lambs under nCPAP immediately following bottle-feeding and may be related to the high milk flow in preterm lambs.ConclusionFurther studies documenting tracheal aspirations are needed, especially in preterm lambs under nCPAP for moderate respiratory difficulties, to further inform future clinical studies.

  5. Purification of tantalum by plasma arc melting

    Science.gov (United States)

    Dunn, Paul S.; Korzekwa, Deniece R.

    1999-01-01

    Purification of tantalum by plasma arc melting. The level of oxygen and carbon impurities in tantalum was reduced by plasma arc melting the tantalum using a flowing plasma gas generated from a gas mixture of helium and hydrogen. The flowing plasma gases of the present invention were found to be superior to other known flowing plasma gases used for this purpose.

  6. Preparation of Carbon-Doped TiO2 Nanopowder Synthesized by Droplet Injection of Solution Precursor in a DC-RF Hybrid Plasma Flow System

    Science.gov (United States)

    Jang, Juyong; Takana, Hidemasa; Ando, Yasutaka; Solonenko, Oleg P.; Nishiyama, Hideya

    2013-08-01

    Carbon-doped titanium dioxide nanopowder has received much attention because of its higher photocatalytic performance, which is practically activated not only by UV, but also by visible light irradiation. In the present study, C-TiO2 nanopowder was synthesized by droplet injection of solution precursor in a DC-RF hybrid plasma flow system, resulting in higher photocatalytic performance even under visible light irradiation. In-flight C-TiO2 nanoparticles reacted with the high concentration of carbon in plasma flow and were then deposited on the surfaces of two quartz tubes in the upstream and downstream regions of this system. The collected C-TiO2 nanopowder contained anatase-rutile mixed-phase TiO2 and TiC, the contents of which depended on the location of the powder collection, the temperature, and the duration of plasma treatment. Highly functional C-TiO2 nanopowder collected in the downstream region exhibited a higher degradation rate of methylene blue than that of single-phase anatase TiO2, even under visible light irradiation, in spite of being TiC.

  7. Packaging materials for plasma sterilization with the flowing afterglow of an N2-O2 discharge: damage assessment and inactivation efficiency of enclosed bacterial spores

    Science.gov (United States)

    Levif, P.; Séguin, J.; Moisan, M.; Soum-Glaude, A.; Barbeau, J.

    2011-10-01

    In conventional sterilization methods (steam, ozone, gaseous chemicals), after their proper cleaning, medical devices are wrapped/enclosed in adequate packaging materials, then closed/sealed before initiating the sterilization process: these packaging materials thus need to be porous. Gaseous plasma sterilization being still under development, evaluation and comparison of packaging materials have not yet been reported in the literature. To this end, we have subjected various porous packagings used with conventional sterilization systems to the N2-O2 flowing afterglow and also a non-porous one to evaluate and compare their characteristics towards the inactivation of B. atrophaeus endospores deposited on a Petri dish and enclosed in such packagings. Because the sterilization process with the N2-O2 discharge afterglow is conducted under reduced-pressure conditions, non-porous pouches can be sealed only after returning to atmospheric pressure. All the tests were therefore conducted with one end of the packaging freely opened, post-sealing being required. The features of these packaging materials, namely mass loss, resistance, toxicity to human cells as well as some characteristics specific to the plasma method used such as ultraviolet transparency, were examined before and after exposure to the flowing afterglow. All of our results show that the non-porous packaging considered is much more suitable than the conventionally used porous ones as far as ensuring an efficient and low-damage sterilization process with an N2-O2 plasma-afterglow is concerned.

  8. DPPH·-luminol chemiluminescence system and its application in the determination of scutellarin in pharmaceutical injections and rat plasma with flow injection analysis.

    Science.gov (United States)

    Yao, Hong; Huang, Xiaomei; Shi, Peiying; Lin, Zhen; Zhu, Meilan; Liu, Ailin; Lin, Xinhua; Tang, Yuhai

    2017-06-01

    In this article, a DPPH·-luminol chemiluminescence (CL) system was reported and the CL mechanism was discussed according to the CL kinetic properties after sequence injecting DPPH· into the DPPH·-luminol reaction mixture. It was observed that scutellarin could inhibit the CL response of the DPPH·-luminol system. Based on this observation, a simple and rapid flow injection CL method was developed for the determination of scutellarin using the inhibition effect in alkaline medium. The optimized chemical conditions for the CL reaction were 5 × 10(-6)  mol/L DPPH· and 1.0 × 10(-4)  mol/L luminol in 0.01 mol/L NaOH. Under optimized conditions, the CL intensity was inversely proportional to the concentration of scutellarin over the ranges 5-2000 and 40-3200 ng/ml in pharmaceutical injection and rat plasma, respectively. The limits of detection (S/N = 3) were 5 and 40 ng/ml in preparations and rat plasma, respectively. Furthermore, the precision, recovery and stability of the validated method were acceptable for the determination of scutellarin in both pharmaceutical injections and rat plasma. The presented method was successfully applied in the determination of scutellarin in pharmaceutical injections and real rat plasma samples. Copyright © 2016 John Wiley & Sons, Ltd.

  9. Water Flow Experiments: Single and Double Bottle Systems

    Indian Academy of Sciences (India)

    Resonance – Journal of Science Education. Current Issue : Vol. 23, Issue 1. Current Issue Volume 23 | Issue 1. January 2018. Home · Volumes & Issues · Categories · Special Issues · Search · Editorial Board · Information for Authors · Subscription ...

  10. Modelling of fluid flow phenomenon in laser+GMAW hybrid welding of aluminum alloy considering three phase coupling and arc plasma shear stress

    Science.gov (United States)

    Xu, Guoxiang; Li, Pengfei; Cao, Qingnan; Hu, Qingxian; Gu, Xiaoyan; Du, Baoshuai

    2018-03-01

    The present study aims to develop a unified three dimensional numerical model for fiber laser+GMAW hybrid welding, which is used to study the fluid flow phenomena in hybrid welding of aluminum alloy and the influence of laser power on weld pool dynamic behavior. This model takes into account the coupling of gas, liquid and metal phases. Laser heat input is described using a cone heat source model with changing peak power density, its height being determined based on the keyhole size. Arc heat input is modeled as a double ellipsoid heat source. The arc plasma flow and droplet transfer are simulated through the two simplified models. The temperature and velocity fields for different laser powers are calculated. The computed results are in general agreement with the experimental data. Both the peak and average values of fluid flow velocity during hybrid welding are much higher than those of GMAW. At a low level of laser power, both the arc force and droplet impingement force play a relatively large role on fluid flow in the hybrid welding. Keyhole depth always oscillates within a range. With an increase in laser power, the weld pool behavior becomes more complex. An anti-clockwise vortex is generated and the stability of keyhole depth is improved. Besides, the effects of laser power on different driving forces of fluid flow in weld pool are also discussed.

  11. Towards a sensory congruent beer bottle: Consumer associations between beer brands, flavours, and bottle designs

    NARCIS (Netherlands)

    Fenko, Anna; Heiltjes, Sanne; van den Berg-Weitzel, Lianne; Lloyd, Peter; Bohemia, Erik

    2016-01-01

    Sensory packaging design congruent with product and brand characteristics may be used as an innovative tool to communicate product and brand values to consumers and to enhance taste experience. This study investigated whether consumers associate sensory properties of beer bottles with certain brand

  12. Statistical analysis of particle flux flowing into the end-target in between attached and detached states in the linear divertor plasma simulator NAGDIS-II

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H. [National Institute for Fusion Science, Toki (Japan); Department of Fusion Science, SOKENDAI, Toki (Japan); Ohno, N.; Onda, T.; Takeyama, K.; Tsuji, Y. [Graduate School of Engineering, Nagoya University, Nagoya (Japan); Kajita, S.; Kuwabara, T. [Institute of Materials and Systems for Sustainability, Nagoya University (Japan)

    2016-08-15

    We have investigated the particle flux flowing into the axisymmetric end-target in the transient state from attached to detached divertor conditions in the linear plasma device NAGDIS-II. In the transient state, a dramatic decrease of the mean particle flux and a large-amplitude fluctuation with negative and positive spikes were observed. We have analyzed the fluctuation with a newly suggested analysis technique: pre-multiplied cubic spectrum with the wavelet transform. Analysis result indicates that these spikes consist of a few kilohertz components. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Exact periodic cross-kink wave solutions for the new (2+1)-dimensional KdV equation in fluid flows and plasma physics.

    Science.gov (United States)

    Liu, Jian-Guo; Du, Jian-Qiang; Zeng, Zhi-Fang; Ai, Guo-Ping

    2016-10-01

    The Korteweg-de Vries (KdV)-type models have been shown to describe many important physical situations such as fluid flows, plasma physics, and solid state physics. In this paper, a new (2 + 1)-dimensional KdV equation is discussed. Based on the Hirota's bilinear form and a generalized three-wave approach, we obtain new exact solutions for the new (2 + 1)-dimensional KdV equation. With the help of symbolic computation, the properties for some new solutions are presented with some figures.

  14. Little bottles and the promise of probiotics.

    Science.gov (United States)

    Burges Watson, Duika; Moreira, Tiago; Murtagh, Madeleine

    2009-03-01

    In this article we explore; regimes of hope' in contemporary bioscience as articulated in spaces of health consumption. We use the case study of probiotic little bottles, highlighting their promissory branding as consumer products, to consider how hope and truth play out across different spaces of health care - the supermarket, media and laboratory. Drawing on work within both sociological and geographic literatures to think about hope, truth and probiotics, this article explores their ambiguous promise through an analysis of their biomedical and popular representation. The seemingly incommensurate promise of probiotics between popular and medical spheres provides the point of departure for an examination of the geographies of hope, truth and selfhood.

  15. Treatment of nursing bottle caries with ribbond

    Directory of Open Access Journals (Sweden)

    Ritu Jindal

    2013-01-01

    Full Text Available Ribbond is a biocompatible, esthetic material made from high-strength polyethylene fiber. Lenowoven polyethylene ribbon (Ribbond has been used successfully for tooth splinting, replacement of missing teeth, reinforcement of provisional acrylic resin fixed partial dentures, and orthodontic retention. This article presents the application of this polyethylene ribbon - RIBBOND - for the treatment of nursing bottle caries. To conclude we suggest that this combined technique of polyethylene fibers and composite material could be a very efficient alternative procedure to conventional treatment plans in pedodontic practice, with excellent esthetics and functional results.

  16. Heat Transfer in Glass, Aluminum, and Plastic Beverage Bottles

    Science.gov (United States)

    Clark, William M.; Shevlin, Ryan C.; Soffen, Tanya S.

    2010-01-01

    This paper addresses a controversy regarding the effect of bottle material on the thermal performance of beverage bottles. Experiments and calculations that verify or refute advertising claims and represent an interesting way to teach heat transfer fundamentals are described. Heat transfer coefficients and the resistance to heat transfer offered…

  17. levels of formaldehyde and acetaldehyde in selected bottled ...

    African Journals Online (AJOL)

    Accer

    ABSTRACT. The levels of formaldehyde and acetaldehyde in bottled drinking water and the effect of storage time and storage conditions on their levels were determined. A total of 144 samples of six brands of bottled drinking water were purchased from Dar es Salaam, Iringa, Mwanza and Arusha regions in Tanzania.

  18. Improvements to the Whoosh Bottle Rocket Car Demonstration

    Science.gov (United States)

    Campbell, Dean J.; Staiger, Felicia A.; Jujjavarapu, Chaitanya N.

    2015-01-01

    The whoosh bottle rocket car has been redesigned to be more reusable and more robust, making it even easier to use as a demonstration. Enhancements of this demonstration, including the use of heat sensitive ink and electronic temperature probes, enable users to find warmer and cooler regions on the surface of the whoosh bottle.

  19. Levels of formaldehyde and acetaldehyde in selected bottled ...

    African Journals Online (AJOL)

    The levels of formaldehyde and acetaldehyde in bottled drinking water and the effect of storage time and storage conditions on their levels were determined. A total of 144 samples of six brands of bottled drinking water were purchased from Dar es Salaam, Iringa, Mwanza and Arusha regions in Tanzania. Analysis was ...

  20. Bisphenol A Detection in Various Brands of Drinking Bottled Water ...

    African Journals Online (AJOL)

    Purpose: To assess whether bisphenol A contamination occurred in seven brands of bottled drinking water in Riyadh, Saudi Arabia. Methods: Liquid-liquid extraction (using dichloromethane) was used to analytically extract bisphenol A from drinking water bottles and a gas chromatograph-mass spectrometer was employed ...

  1. Quality characteristics of commercial bottled water sold in Owerri ...

    African Journals Online (AJOL)

    The quality characteristics of commercial bottled water sold in Owerri, Imo State, Nigeria were investigated to determine their physical, chemical and bacteriological content. The four brands of bottled water investigated were Mevok ®, Ozonized April ®, Lacrystal ® and Eva ®. The mean turbidity value of all the samples were ...

  2. Bacteriological Evaluation of Water Bottles Used by Nursery School ...

    African Journals Online (AJOL)

    Bacteriological evaluation of water bottles used by nursery school pupils in Owerri metropolis was carried out. Eleven bacterial genera were isolated from the water bottle samples. These included Bacillus, E. coli, Enterobacter, Klebsiella, Micrococcus, Proteus, Pseudomonas, Staphylococcus, Salmonella, Shigella and ...

  3. techno-economic packaging of palm wine preservation and bottling ...

    African Journals Online (AJOL)

    Admin

    KEYWORDS: Entrepreneur, Palm Wine Preservation, Palmwine Bottling Technology, Techno-Economic ... Nigeria Limited palm wine bottling plant installed by .... 680.02. FACTORY COST. 16,852.51. 17,880.39. 19,227.90. 20,309.98 21,405.66. Admin Overhead. Marketing Overhead. 1,135.12. 850.00. 1,191.88. 892.50.

  4. 27 CFR 25.158 - Tax computation for bottled beer.

    Science.gov (United States)

    2010-04-01

    ... bottled beer. 25.158 Section 25.158 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Tax on Beer Determination of Tax § 25.158 Tax computation for bottled beer. Barrel equivalents for various case sizes are as follows: (a) For U.S. measure...

  5. Bacteriological quality of bottled water sold on the Ghanaian market ...

    African Journals Online (AJOL)

    Consumption of bottled water is increasing rapidly in developing countries especially among the middle and high income earners as it is generally perceived to be pure, clean and of good quality. This has led to the sale of different brands of bottled water on the Ghanaian market. Although disease outbreaks due to ...

  6. Wooden beverage cases cause little damage to bottle caps

    Science.gov (United States)

    R. Bruce Anderson; William C. Miller

    1973-01-01

    Wooden beverage cases cause little damage to aluminum resealable caps during distribution. A study at bottling plants and distribution warehouses showed that an average of 1 bottle out of 4,000 has cap damage. Most of the damage was attributed to handling at the warehouse and in transit. Some recommendations are given for improvement of wooden beverage cases to prevent...

  7. Infant Bottle-Feeding Practice, Agaro Town, Southwest Ethiopia ...

    African Journals Online (AJOL)

    BACKGROUND: The prevalence and duration of breast-feeding is declining and being replaced by formula milk. The morbidity and mortality of bottle fed infants is much greater than breast fed infants. The aim of this study was to determine the prevalence of bottle-feeding and to assess factors that contribute to the practice ...

  8. 27 CFR 27.206 - Bottles not constituting approved containers.

    Science.gov (United States)

    2010-04-01

    ... approved containers. 27.206 Section 27.206 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Requirements for Liquor Bottles § 27.206 Bottles not constituting approved containers. The appropriate TTB...

  9. Bottled or tap? Testing perceptions about water in Lebanon and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-06-09

    Jun 9, 2016 ... Researchers compared water quality available in two informal settlements in Lebanon and Jordan. Tests were conducted to compare water supplied by the municipality and bottled water. The results: tests showed that their quality is similar, although the brand of the bottled water and how it is stored affected ...

  10. Computed Tomography characterization of the Green Fiber Bottle

    DEFF Research Database (Denmark)

    Saxena, Prateek; Bissacco, Giuliano

    The work carried out in this research aims at identifying suitable ways for thorough characterization of the quality of paper bottles. Industrial X-ray Computed Tomography (XCT) is particularly advantageous in determining the quality of paper bottles and thus correlating it with the production...

  11. Shear-flow driven dissipative instability and investigation of nonlinear drift-vortex modes in dusty plasmas with non-thermal ion population

    Science.gov (United States)

    Gul-e-Ali, Masood, W.; Mirza, Arshad M.

    2017-12-01

    The shear flow in dust dynamics driven waves in combination with the dust-neutral drag is studied in a plasma comprising of ions, electrons, and dust. Non-thermal population of ions is considered, which has been observed by many satellite missions. It is found that the dissipative instability produced by dust sheared flow and dust-neutral drag gets modified by the presence of nonthermal ions. It is found that the dissipative instability enhances for the Cairns distribution, whereas the kappa distribution arrests the growth of this instability. In the nonlinear regime, the formation of vortices in the system is studied. It is found that the nonthermal population of ions significantly alters these structures in comparison with their Maxwellian counterpart. The results obtained in this paper may have relevance in the planetary magnetospheres where the dust particles are present and non-Maxwellian distribution of particles have been observed by Freja and Viking satellites.

  12. Changes in plasma volume, in transcapillary escape rate of albumin and in subcutaneous blood flow during hypoglycaemia in man

    DEFF Research Database (Denmark)

    Hilsted, J; Bonde-Petersen, F; Madsbad, S

    1985-01-01

    and transcapillary escape rate increased significantly during hypoglycaemia. Skin temperature and local subcutaneous adipose tissue blood flow were measured in four different regions. Both tended to decrease during hypoglycaemia and decreased significantly 2 h after hypoglycaemia. There was no correlation between...... changes in the two measurements, suggesting that there is no simple relationship between subcutaneous blood flow and skin temperature during hypoglycaemia....

  13. In-house validation of a method for determination of silver nanoparticles in chicken meat based on asymmetric flow field-flow fractionation and inductively coupled plasma mass spectrometric detection

    DEFF Research Database (Denmark)

    Löschner, Katrin; Navratilova, Jana; Grombe, Ringo

    2015-01-01

    spectrometric detection (AF4-ICP-MS) was applied for quantitative analysis of silver nanoparticles (AgNPs) in a chicken meat matrix following enzymatic sample preparation. For the first time an analytical validation of nanoparticle detection in a food matrix by AF4-ICP-MS has been carried out and the results......Nanomaterials are increasingly used in food production and packaging, and validated methods for detection of nanoparticles (NPs) in foodstuffs need to be developed both for regulatory purposes and product development. Asymmetric flow field-flow fractionation with inductively coupled plasma mass...... showed repeatable and intermediately reproducible determination of AgNP mass fraction and size. The findings demonstrated the potential of AF4-ICP-MS for quantitative analysis of NPs in complex food matrices for use in food monitoring and control. The accurate determination of AgNP size distribution...

  14. IgA and IgM protein primarily drive plasma corona-induced adhesion reduction of PLGA nanoparticles in human blood flow.

    Science.gov (United States)

    Sobczynski, Daniel J; Eniola-Adefeso, Omolola

    2017-06-01

    The high abundance of immunoglobulins (Igs) in the plasma protein corona on poly(lactic-co-glycolic) acid (PLGA)-based vascular-targeted carriers (VTCs) has previously been shown to reduce their adhesion to activated endothelial cells (aECs) in human blood flow. However, the relative role of individual Ig classes (e.g., IgG, IgA, and IgM) in causing adhesion reduction remains largely unknown. Here, we characterized the influence of specific Ig classes in prescribing the binding efficiency of PLGA nano-sized VTCs in blood flow. Specifically, we evaluated the flow adhesion to aECs of PLGA VTCs with systematic depletion of various Igs in their corona. Adhesion reduction was largely eliminated for PLGA VTCs when all Igs were removed from the corona. Furthermore, re-addition of IgA or IgM to the Igs-depleted corona reinstated the low adhesion of PLGA VTCs, as evidenced by ∼40-70% reduction relative to particles with an Igs-deficient corona. However, re-addition of a high concentration of IgG to the Igs-depleted corona did not cause significant adhesion reduction. Overall, the presented results reveal that PLGA VTC adhesion reduction in blood flows is primarily driven by high adsorption of IgA and IgM in the particle corona. Pre-coating of albumin on PLGA VTCs mitigated the extent of adhesion reduction in plasma for some donors but was largely ineffective in general. Overall, this work may shed light into effective control of protein corona composition, thereby enhancing VTC functionality in vivo for eventual clinical use.

  15. Simulations of the Neutral-beam-induced Rotation, Radial Electric Field, and Flow Shearing Rate in Next-step Burning Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    R.V. Budny

    2002-08-13

    Toroidal rotation of plasmas in present tokamaks is beneficial for increasing the stability to wall-induced MHD and appears to reduce the anomalous transport associated with micro-turbulence. This paper calculates the toroidal rotation expected from neutral-beam injection in the proposed FIRE and ITER-FEAT tokamak reactors. Self-consistent burning plasmas for these tokamaks have been constructed using the TRANSP plasma analysis code. Neutral-beam injection has been proposed for FIRE and ITER-FEAT. The neutral-beam-induced torques are computed, and assumptions for the anomalous transport of toroidal angular momentum are used to calculate the toroidal rotation profiles. The central Mach numbers are about 3-8%. The ratio of the rotation speed to the Alfvin speed is less than 1%. Assuming neoclassical poloidal rotation and force balance, the radial electric field and flow shearing rate are calculated. Peak shearing rates near the outboard edge are in the 10-100 krad/s range.

  16. Modulation of Jupiter's plasma flow, polar currents, and auroral precipitation by solar wind-induced compressions and expansions of the magnetosphere: a simple theoretical model

    Directory of Open Access Journals (Sweden)

    S. W. H. Cowley

    2007-06-01

    Full Text Available We construct a simple model of the plasma flow, magnetosphere-ionosphere coupling currents, and auroral precipitation in Jupiter's magnetosphere, and examine how they respond to compressions and expansions of the system induced by changes in solar wind dynamic pressure. The main simplifying assumption is axi-symmetry, the system being modelled principally to reflect dayside conditions. The model thus describes three magnetospheric regions, namely the middle and outer magnetosphere on closed magnetic field lines bounded by the magnetopause, together with a region of open field lines mapping to the tail. The calculations assume that the system is initially in a state of steady diffusive outflow of iogenic plasma with a particular equatorial magnetopause radius, and that the magnetopause then moves rapidly in or out due to a change in the solar wind dynamic pressure. If the change is sufficiently rapid (~2–3 h or less the plasma angular momentum is conserved during the excursion, allowing the modified plasma angular velocity to be calculated from the radial displacement of the field lines, together with the modified magnetosphere-ionosphere coupling currents and auroral precipitation. The properties of these transient states are compared with those of the steady states to which they revert over intervals of ~1–2 days. Results are shown for rapid compressions of the system from an initially expanded state typical of a solar wind rarefaction region, illustrating the reduction in total precipitating electron power that occurs for modest compressions, followed by partial recovery in the emergent steady state. For major compressions, however, typical of the onset of a solar wind compression region, a brightened transient state occurs in which super-rotation is induced on closed field lines, resulting in a reversal in sense of the usual magnetosphere-ionosphere coupling current system. Current system reversal results in accelerated auroral electron

  17. Modulation of Jupiter's plasma flow, polar currents, and auroral precipitation by solar wind-induced compressions and expansions of the magnetosphere: a simple theoretical model

    Directory of Open Access Journals (Sweden)

    S. W. H. Cowley

    2007-06-01

    Full Text Available We construct a simple model of the plasma flow, magnetosphere-ionosphere coupling currents, and auroral precipitation in Jupiter's magnetosphere, and examine how they respond to compressions and expansions of the system induced by changes in solar wind dynamic pressure. The main simplifying assumption is axi-symmetry, the system being modelled principally to reflect dayside conditions. The model thus describes three magnetospheric regions, namely the middle and outer magnetosphere on closed magnetic field lines bounded by the magnetopause, together with a region of open field lines mapping to the tail. The calculations assume that the system is initially in a state of steady diffusive outflow of iogenic plasma with a particular equatorial magnetopause radius, and that the magnetopause then moves rapidly in or out due to a change in the solar wind dynamic pressure. If the change is sufficiently rapid (~2–3 h or less the plasma angular momentum is conserved during the excursion, allowing the modified plasma angular velocity to be calculated from the radial displacement of the field lines, together with the modified magnetosphere-ionosphere coupling currents and auroral precipitation. The properties of these transient states are compared with those of the steady states to which they revert over intervals of ~1–2 days. Results are shown for rapid compressions of the system from an initially expanded state typical of a solar wind rarefaction region, illustrating the reduction in total precipitating electron power that occurs for modest compressions, followed by partial recovery in the emergent steady state. For major compressions, however, typical of the onset of a solar wind compression region, a brightened transient state occurs in which super-rotation is induced on closed field lines, resulting in a reversal in sense of the usual magnetosphere-ionosphere coupling current system. Current system reversal results in accelerated auroral

  18. On the nature of radial transport across sheared zonal flows in electrostatic ion-temperature-gradient gyrokinetic tokamak plasma turbulencea)

    Science.gov (United States)

    Sánchez, R.; Newman, D. E.; Leboeuf, J.-N.; Carreras, B. A.; Decyk, V. K.

    2009-05-01

    It is argued that the usual understanding of the suppression of radial turbulent transport across a sheared zonal flow based on a reduction in effective transport coefficients is, by itself, incomplete. By means of toroidal gyrokinetic simulations of electrostatic, ion-temperature-gradient turbulence, it is found instead that the character of the radial transport is altered fundamentally by the presence of a sheared zonal flow, changing from diffusive to anticorrelated and subdiffusive. Furthermore, if the flows are self-consistently driven by the turbulence via the Reynolds stresses (in contrast to being induced externally), radial transport becomes non-Gaussian as well. These results warrant a reevaluation of the traditional description of radial transport across sheared flows in tokamaks via effective transport coefficients, suggesting that such description is oversimplified and poorly captures the underlying dynamics, which may in turn compromise its predictive capabilities.

  19. Application of infrared thermography for online monitoring of wall temperatures in inductively coupled plasma torches with conventional and low-flow gas consumption

    Science.gov (United States)

    Engelhard, Carsten; Scheffer, Andy; Maue, Thomas; Hieftje, Gary M.; Buscher, Wolfgang

    2007-10-01

    Inductively coupled plasma (ICP) sources typically used for trace elemental determination and speciation were investigated with infrared (IR) thermography to obtain spatially resolved torch temperature distributions. Infrared thermographic imaging is an excellent tool for the monitoring of temperatures in a fast and non-destructive way. This paper presents the first application of IR thermography to inductively coupled plasma torches and the possibility to investigate temperatures and thermal patterns while the ICP is operating and despite background emission from the plasma itself. A fast and easy method is presented for the determination of temperature distributions and stress features within ICP torches. Two different ICP operating torches were studied: a commercially available Fassel-type ICP unit with 14 L min - 1 total Ar consumption and a SHIP torch with the unusually low Ar flow of 0.6 L min - 1 . Spatially resolved infrared images of both torches were obtained and laterally resolved temperature profiles were extracted. After temperature-resolved calibration of the emissivity (between 0.5 and 0.35 at 873-1323 K) and transmission (20% between 3.75 and 4.02 μm) of the fused quartz used in the torch construction, an image correction was applied. Inhomogeneous temperature distributions with locally defined stress areas in the conventional Fassel-type torch were revealed. As a general trend, it was found that the SHIP torch exhibited higher temperatures ( Tmax = 1580 K) than the conventional torch ( Tmax = 730 K). In the former case, torch sites with efficient and inefficient cooling were discovered and the external flow of cooling air (24-48 m s - 1 ) was identified as the limiting factor.

  20. 21 CFR 1250.85 - Drinking fountains and coolers; ice; constant temperature bottles.

    Science.gov (United States)

    2010-04-01

    ... temperature bottles. 1250.85 Section 1250.85 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... Drinking fountains and coolers; ice; constant temperature bottles. (a) Drinking fountains and coolers shall... temperature bottles. (c) Constant temperature bottles and other containers used for storing or dispensing...

  1. Determining fluid level in a translucent eye-drop bottle: transillumination by penlight.

    Science.gov (United States)

    Kayikcioğlu, O; Akkin, C; Ates, H

    We describe an easy way to determine eye-drop contents in translucent bottles. Transillumination of eye-drop bottles from behind or the bottom by using a penlight clearly defines the fluid levels. The described procedure may prevent disposal of eye-drop bottles containing useful amounts of medication and prevent Ophthalmologists and Patients unexpectedly coming across an empty bottle.

  2. 27 CFR 27.207 - Bottles to be used for display purposes.

    Science.gov (United States)

    2010-04-01

    ... display purposes. 27.207 Section 27.207 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... Requirements for Liquor Bottles § 27.207 Bottles to be used for display purposes. Empty liquor bottles may be imported and furnished to liquor dealers for display purposes, provided each bottle is marked to show that...

  3. 27 CFR 19.635 - Bottles to be used for display purposes.

    Science.gov (United States)

    2010-04-01

    ... display purposes. 19.635 Section 19.635 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... Requirements Liquor Bottle Requirements § 19.635 Bottles to be used for display purposes. Liquor bottles may be furnished to liquor dealers for display purposes, provided that each bottle is marked to show that it is to...

  4. Physiologic stability of newborns during cup- and bottle-feeding.

    Science.gov (United States)

    Howard, C R; de Blieck, E A; ten Hoopen, C B; Howard, F M; Lanphear, B P; Lawrence, R A

    1999-11-01

    To prevent breastfeeding problems, cup-feeding has been recommended as a method of providing medically necessary supplemental feedings to breastfed infants. To compare amounts ingested, administration time, and infant physiologic stability during cup-, bottle-, and breastfeeding. A total of 98 term, healthy newborns were randomized to either cup-feeding (n = 51) or bottle-feeding (n = 47). The heart (HR), respiratory (RR), and oxygen (O(2)) saturation rates were monitored on these infants and 25 breastfed newborns during 1 feeding. Differences in amounts ingested and administration times were evaluated with t tests and physiologic data with repeat measures analysis of variance. There were no significant differences in administration time, amounts ingested or overall HR, RR, and (O(2)) saturation rates, between cup and bottle groups. Breastfed infants had longer administration times and lower overall HR, RR, and higher O(2) saturation as compared with cup- and bottle-fed infants. Administration times, amounts ingested, and infant physiologic stability do not differ with cup- and bottle-feeding. Breastfeeding takes longer than cup- or bottle-feeding, but infants experience less physiologic variability. These data support cup-feeding as an alternative to bottle-feeding for supplying supplements to breastfed infants.

  5. Prolonged bedtime bottle feeding and respiratory symptoms in infants.

    Science.gov (United States)

    Kim, Hye-Young; Han, Youngshin; Pyun, Younkyoung; Kim, Jihyun; Ahn, Kangmo; Lee, Sang-Il

    2011-04-01

    Infants with chronic respiratory symptoms should be evaluated thoroughly because there are various causes which are different from those of children and adolescents. This study was designed to investigate the relationship between chronic respiratory symptoms and bedtime bottle feeding in infants after the age of 6 months. We conducted a prospective study that included 44 infants who presented with respiratory symptoms for more than 8 weeks and also had been bottle-fed during bedtime even after 6 months of age. The infants were divided into 2 groups; infants who discontinued bedtime bottle feeding and those who did not. Respiratory symptom scores were graded with a four-point scale at 0, 1, 2 and 3 months, and were compared between the 2 groups. Twenty eight infants (63.6%) stopped being bottle-fed during bedtime and 16 infants (36.4%) were still bottle-fed. The respiratory symptom scores were significantly decreased in infants who stopped bedtime bottle feeding (p = 0.0003). It is suggested that prolonged bedtime bottle feeding might be one of the causes of chronic respiratory symptoms in infants.

  6. Fluoride content of bottled waters available in Northern Greece.

    Science.gov (United States)

    Ahiropoulos, V

    2006-03-01

    The aim of this study was to evaluate the fluoride content of bottled drinking waters commercially available in northern Greece and to report on the accuracy of the labelling of fluoride concentration. Twenty-two randomly selected commercial brands of bottled water were obtained from three supermarkets in Thessaloniki, Greece. Three bottles of each brand were purchased. Following calibration, six tests were conducted on each bottle using a combination fluoride-ion selective electrode (Orion, 96-09-00, MA, USA). The average reading for each brand was estimated and also compared with the fluoride content printed on the label. The mean (+/- SD) fluoride content of the bottled water samples was 0.35 (+/- 1.00) mg F/L with a range from 0.05 to 4.8 mg F/L. Only 18% (N = 4) of brands tested mention the fluoride concentration on the label, and 90% (N = 22) had a tested fluoride between 0.05 and 0.21 mg F/L. Of the remaining two brands, one was found to contain 0.3 mg F/L without having the fluoride concentration indicated on the label, and the other was labelled at 6 mg F/L, whereas the concentration was estimated as 4.8 mg F/L. The use of bottled water may be a significant source of systemic fluoride and therefore be considered as a risk factor for dental fluorosis in young children. This article shows that bottled drinking waters contain differing concentrations of fluoride. The manufacturers' labelling of fluoride concentrations may be inaccurate. When prescribing fluoride supplements, dentists should be aware of the fluoride content of bottled waters used by paediatric patients, especially brands with a concentration higher than 0.3 mg F/L. In view of the wide variation of fluoride concentration in the tested bottled waters, regulatory guidelines for controlling concentration in order to prevent dental fluorosis are recommended.

  7. A Three Dimensional Model of the Plasma Flow and Magnetic Fields in the Dayside Ionosphere of Venus.

    Science.gov (United States)

    1982-03-01

    and for his astute sug- gestions during the course of this research. Under his guidance, I have gained insights into physics which not only helped me... ambient environment. Zwan and Wolf showed that the plasma depletion mechanism is not axisymmetric and the resulting velocity asymmetry (v, > v...ionosphere. At lower altitudes, the velocity asymmetry is reduced due to frequent collisions with the ambient , thermal ionospheric ions. The magnitudes of

  8. Innovative Design of Plastic Bottle Recycling Box Based on ARM

    Directory of Open Access Journals (Sweden)

    Yuedong Xiong

    2014-04-01

    Full Text Available Aiming at the problems of on-site plastic bottles recycling and the reuse of waste, the automatic recycling system was developed on the basis of ARM. As the main controller, ARM not only controls the mechanical system of the collector to recover and break plastic bottles, but also communicates with and rewards the user by the automatic reward system through the wireless network. The experimental prototype test results show: post treated fragments of plastic bottles are small, which are convenient to transport and take advantage of; the operation of recovery is easy, and the interface of man-machine interaction is friendly which is easy to expand functions.

  9. Evolutionary medicine: bottle feeding, birth spacing, and autism.

    Science.gov (United States)

    Gallup, Gordon G; Hobbs, Dawn R

    2011-09-01

    To compensate for the high metabolic costs of lactation, the likelihood of re-impregnation shortly after childbirth is normally reduced due to hormonal changes triggered by breast feeding during the postpartum period. Nowadays, however, bottle feeding as a substitute for breast feeding precludes such changes and leads to early postpartum reinstatement of fertility. We suggest that recent data showing the risk of autism goes up dramatically as the time between pregnancies goes down [1] may be a byproduct of bottle feeding. The decision to bottle feed your last child may unwittingly put your next child at risk of being autistic. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Dynamically tunable optical bottles from an optical fiber

    DEFF Research Database (Denmark)

    Chen, Yuhao; Yan, Lu; Rishøj, Lars Søgaard

    2012-01-01

    Optical fibers have long been used to impose spatial coherence to shape free-space optical beams. Recent work has shown that one can use higher order fiber modes to create more exotic beam profiles. We experimentally generate optical bottles from Talbot imaging in the coherent superposition of two...... fiber modes excited with long period gratings, and obtain a 28 μm × 6 μm bottle with controlled contrast up to 10.13 dB. Our geometry allows for phase tuning of one mode with respect to the other, which enables us to dynamically move the bottle in free space....

  11. Occurrence of clostridia in glass bottled foods.

    Science.gov (United States)

    Fujisawa, T; Aikawa, K; Furukawa, I; Takahashi, T

    2000-03-25

    Forty-one marketed samples of imported and domestic glass bottled foods were tested for clostridia contamination. It was detected in nine (22%) samples. Clostridia were isolated from fish sauce (Nam pla, Nuoc-mam), dressing, mustard, hot and sour soup mix (Tom Yum), mysids boiled down in soy, and salmon flakes. The origin of all clostridia positive samples was Asia. Clostridium botulinum and C. perfringens were not detected. The frequency of occurrence was higher by enrichment broth culture detection methods than by agar plate or pouch methods. These findings suggest that the number of bacteria in most of these clostridia positive food samples is very low, and the use of enrichment methods for detection of clostridia is essential.

  12. Radioactivity in bottled waters sold in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Davila Rangel, J.I. E-mail: idavila@cantera.reduaz.mx; Lopez del Rio, H.; Mireles Garcia, F.; Quirino Torres, L.L.; Villalba, M.L.; Colmenero Sujo, L.; Montero Cabrera, M.E

    2002-06-01

    Measurements of gross alpha and beta activities were made on 21 domestic and international brands of bottled (purified and mineral) water sold in the Mexican market to assess its radiological quality. Alpha and beta activities were determined using a liquid-scintillation detector with pulse-shape analysis feature. All the purified water had values of beta activity lower than the limit for potable drinking water (1.0 Bq/l), while three brands surpassed the limit of alpha activity (0.1 Bq/l). The limit for alpha radioactivity content was exceed by three mineral waters; the results show a correlation between radioactivity content and mineral salts, which are related with the origin and treatment of the waters.

  13. Ampoule Bottle Detection Equipment Research and Development

    Directory of Open Access Journals (Sweden)

    Liu Xinyu

    2015-01-01

    Full Text Available With the continuous development of computer vision technology, its application is more and more extensive. In recent years, the application of computer vision technology in the area of medical packing detection also made great achievements. This paper detailed a scientific and reasonable scheme of an ampoule bottle automatic detection equipment. In this scheme we use the computer vision technology and CNC technology, and select the appropriate transport mechanism and cameras to get images of ampoules. After getting the images, we use a software named MATLAB, which can deal with the images, to obtain some useful information about the ampoules. Then we can evaluate the quality of the ampoule according to these information.

  14. Nonlinear saturation of Rayleigh-Taylor instability and generation of shear flow in equatorial spread-F plasma

    Directory of Open Access Journals (Sweden)

    N. Chakrabarti

    2001-01-01

    Full Text Available An analysis of low order mode coupling equations is used to describe the nonlinear behaviour of the Rayleigh-Taylor (RT instability in the equatorial ionosphere. The nonlinear evolution of RT instability leads to the development of shear flow. It is found that there is an interplay between the nonlinearity and the shear flow which compete with each other and saturate the RT mode, both in the collisionless and collisional regime. However, the nonlinearly saturated state, normally known as vortices or bubbles, may not be stable. Under certain condition these bubbles are shown to be unstable to short scale secondary instabilities that are driven by the large gradients which develop within these structures. Some understanding of the role of collisional nonlinearity in the  shear flow generations is also discussed.

  15. Schlieren visualization of flow-field modification over an airfoil by near-surface gas-density perturbations generated by a nanosecond-pulse-driven plasma actuator

    Science.gov (United States)

    Komuro, Atsushi; Takashima, Keisuke; Konno, Kaiki; Tanaka, Naoki; Nonomura, Taku; Kaneko, Toshiro; Ando, Akira; Asai, Keisuke

    2017-06-01

    Gas-density perturbations near an airfoil surface generated by a nanosecond dielectric-barrier-discharge plasma actuator (ns-DBDPA) are visualized using a high-speed Schlieren imaging method. Wind-tunnel experiments are conducted for a wind speed of 20 m s-1 with an NACA0015 airfoil whose chord length is 100 mm. The results show that the ns-DBDPA first generates a pressure wave and then stochastic perturbations of the gas density near the leading edge of the airfoil. Two structures with different characteristics are observed in the stochastic perturbations. One structure propagates along the boundary between the shear layer and the main flow at a speed close to that of the main flow. The other propagates more slowly on the surface of the airfoil and causes mixing between the main and shear flows. It is observed that these two heated structures interact with each other, resulting in a recovery in the negative pressure coefficient at the leading edge of the airfoil.

  16. Fractionation and Characterization of High Aspect Ratio Gold Nanorods Using Asymmetric-Flow Field Flow Fractionation and Single Particle Inductively Coupled Plasma Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Thao M. Nguyen

    2015-07-01

    Full Text Available Gold nanorods (GNRs are of particular interest for biomedical applications due to their unique size-dependent longitudinal surface plasmon resonance band in the visible to near-infrared. Purified GNRs are essential for the advancement of technologies based on these materials. Used in concert, asymmetric-flow field flow fractionation (A4F and single particle inductively coupled mass spectrometry (spICP-MS provide unique advantages for fractionating and analyzing the typically complex mixtures produced by common synthetic procedures. A4F fractions collected at specific elution times were analyzed off-line by spICP-MS. The individual particle masses were obtained by conversion of the ICP-MS pulse intensity for each detected particle event, using a defined calibration procedure. Size distributions were then derived by transforming particle mass to length assuming a fixed diameter. The resulting particle lengths correlated closely with ex situ transmission electron microscopy. In contrast to our previously reported observations on the fractionation of low-aspect ratio (AR GNRs (AR < 4, under optimal A4F separation conditions the results for high-AR GNRs of fixed diameter (≈20 nm suggest normal, rather than steric, mode elution (i.e., shorter rods with lower AR generally elute first. The relatively narrow populations in late eluting fractions suggest the method can be used to collect and analyze specific length fractions; it is feasible that A4F could be appropriately modified for industrial scale purification of GNRs.

  17. Bottled Water: United States Consumers and Their Perceptions of Water Quality

    OpenAIRE

    Hu, Zhihua; Morton, Lois Wright; Mahler, Robert L.

    2011-01-01

    Consumption of bottled water is increasing worldwide. Prior research shows many consumers believe bottled water is convenient and has better taste than tap water, despite reports of a number of water quality incidents with bottled water. The authors explore the demographic and social factors associated with bottled water users in the U.S. and the relationship between bottled water use and perceptions of the quality of local water supply. They find that U.S. consumers are more likely to report...

  18. Inappropriate bottle use: an early risk for overweight? Literature review and pilot data for a bottle-weaning trial.

    Science.gov (United States)

    Bonuck, Karen A; Huang, Vincent; Fletcher, Jason

    2010-01-01

    Identifying early risk factors for childhood obesity is critical, as weight in infancy and early childhood tracks to later periods. Continued bottle use - primarily from excess milk intake - is emerging as a potential risk factor for early childhood overweight. Over three fourths of US infants drink from bottles beyond the recommended weaning age of 12 months, and two thirds of UK infants use a bottle at 18 months. This paper is divided into three parts. Part 1 reviews the literature on beverage intake, weight and bottle use in young children. Part II describes pilot data on milk bottle use and weight in 12-60-month-olds, collected prior to a randomized controlled (RCT) trial of a bottle-weaning intervention. Median daily milk bottle consumption at 12 months was 5.0 (interquartile range = 3-6). Among 12-36-month-olds, current users were significantly more likely to be >95th% weight-for-height (19% vs. 0%, P 85% weight-for-height (27% vs. 11%, P bottle use was not associated with either overweight or obesity in 37-60-month-olds. Part III describes the RCT, begun in fall 2008. It is enrolling 464 parent/12-month-old dyads from a nutrition assistance programme for low-income families. Children's bottle use, anthropometrics, dietary intake and nutrient density (via 24 h recall) are assessed quarterly through 24 months of age. For the intervention, site nutritionists employ a project-developed, visually attractive flip chart. An observational study nested within the RCT will describe dietary changes during this period of feeding transitions.

  19. Adhesion of blood platelets under flow to wettability gradient polyethylene surfaces made in a shielded gas plasma

    NARCIS (Netherlands)

    Spijker, HT; Busscher, HJ; Graaff, R; van Oeveren, W; Bos, R.R.M.

    2002-01-01

    Adhesion and activation of platelets are important steps in the thrombosis of blood after contact with a biomaterial surface and are governed, in part, by the wettability of the surface. Since most implanted devices are in contact with blood under flow conditions, it is important to study the effect

  20. The frequency of bottle feeding as the main factor of baby bottle tooth decay syndrome

    Directory of Open Access Journals (Sweden)

    Mochamad Fahlevi Rizal

    2010-03-01

    Full Text Available Background: Dental caries remains as main problem in Indonesia and its prevalence is high (90.05%. However, there is no appropriate data that can be used to analyze dental caries in toddlers, especially baby bottle tooth decay syndrome (BBTD, though the number of BBTD cases is high in some pediatric dental clinics (90% of patients visiting the clinics. Even though some factors have already been considered to be the risk factor of BBTD, the main risk factor of BBTD is still unknown, especially BBTD in Indonesia. Purpose: This research was aimed to obtain data relating with bottle-feeding habit in 3-5 year old children in Indonesia and its caries risk. Method: The study was an observational research conducted with clinical examination through caries status (deft of each child deserved by pediatric dentists and through questionnaire distributed to parents to examine the risk factor of BBTD. Observation was conducted on 62 children in the range of age 3 to 5 years old with bottle-feeding habit. Result: The results revealed that status of caries was various. The data showed that the frequency of bottle feeding more than twice could trigger BBTD 2.27 times higher than other factors such as the use of bottle feeding as a pacifier prior sleeping, the period of bottle-feeding, and the breast-feeding experience. Conclusion: though milk as subtract can possibly become a factor triggering caries, the frequency of bottle-feeding is highly considered as main factor. Since it could modulated the bacterial colonization on dental surface, which affects its virulence.Latar belakang: Karies masih menjadi masalah utama di Indonesia. Dalam praktek sehari-hari prevalensi karies masih sangat tinggi (90.05%. Belum ada data yang memadai dalam penelaahan karies yang spesifik pada anak balita selama ini khususnya kasus sindroma karies botol (SKB sementara itu kasus SKB ditemukan sangat tinggi di beberapa klinik gigi anak (90% dari jumlah pasien yang datang ke klinik

  1. Randomized controlled trial of bottle weaning intervention: a pilot study.

    Science.gov (United States)

    Kahn, Richard; Bonuck, Karen; Trombley, Michelle

    2007-03-01

    Inappropriate baby bottle use is associated with tooth decay, anemia, and overweight, and it may adversely affect dietary patterns. Parents often do not follow guidance to wean by 18 months of life. We piloted a brief, counseling-based weaning intervention in an urban WIC agency among primarily Hispanic parent/toddler dyads. At baseline (n = 48), toddlers consumed a mean 4.7 bottles/day. At follow-up (n = 39), the intervention group consumed fewer mean bottles/day than controls (0.09 vs 2.0 bottles/day, P < .045). Half the toddlers in the experimental group and one third of the control groups weaned completely. Parents of weaned children were satisfied with the outcome.

  2. Relativistic Cyclotron Resonance Shape in Magnetic Bottle Geonium

    National Research Council Canada - National Science Library

    Hans Dehmelt; Richard Mittleman; Yuan Liu

    1988-01-01

    The thermally excited axial oscillation of the electron through the weak magnetic bottle needed for the continuous Stern-Gerlach effect modulates the cyclotron frequency and produces a characteristic...

  3. Bottler of the Year: Coca-Cola Bottling Co. Consolidated

    National Research Council Canada - National Science Library

    Elizabeth Fuhrman

    2010-01-01

    .... Coca-Cola Bottling Co Consolidated, Charlotte, NC, has built its core business this year through innovative pricing strategies, enabling its sales force with new technology, grass roots marketing...

  4. 27 CFR 31.203 - Possession of used liquor bottles.

    Science.gov (United States)

    2010-04-01

    ... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS ALCOHOL BEVERAGE DEALERS Reuse and Possession of Used Liquor... recycling or reclaiming the glass or other approved liquor bottle material. (26 U.S.C. 5301) ...

  5. Determination of sperm concentration using flow cytometry with simultaneous analysis of sperm plasma membrane integrity in zebrafish Danio rerio.

    Science.gov (United States)

    Yang, Huiping; Daly, Jonathan; Tiersch, Terrence R

    2016-04-01

    Control of sperm concentration is required to ensure consistent and reproducible results for cryopreservation and in vitro fertilization protocols. Determination of sperm concentration is traditionally performed with a counting chamber (e.g., hemocytometer), or more recently with a spectrophotometer. For small-sized biomedical model fishes, the availability of sperm sample is limited to microliters, so it is desirable to develop fast and accurate approaches for concentration determination that also minimize sample use. In this study, a new approach was developed for sperm concentration determination using a flow cytometer (Accuri C6, BD Biosciences, San Jose, CA) with simultaneous measurement of sperm membrane integrity after fluorescent staining with SYBR(®) -14 and propidium iodide (PI) in sperm from Zebrafish Danio rerio. The goal was to develop a protocol for simultaneous determination of sperm quality and quantity by flow cytometry. The objectives were to (1) determine the effects of sample volume (250 and 500 µl) and analysis volume (10 and 50 µl) on the accuracy of particle counting using standard volumetric validation beads; (2) identify the effective range of sperm concentrations that flow cytometry can measure; (3) test the precision and reproducibility of the sperm concentration measurements; and (4) verify the flow cytometry approach by comparison with measurement with a hemocytometer and a microspectrophotometer. Sample volumes of 250 and 500 µl and analysis volumes of 10 and 50 µl did not affect bead count with the factory-set flow rates of "medium" or "fast," and the precision and accuracy was retained across a concentration range of 1 × 10(3) -1 × 10(7) cells/ml. The approach developed in this study was comparable to traditional methodologies such as hemocytometer or microspectrophotometer. This study provides an efficient, accurate, and rapid method for determination of sperm concentration using flow cytometry while providing

  6. Physical, chemical and microbial analysis of bottled drinking water.

    Science.gov (United States)

    Sasikaran, S; Sritharan, K; Balakumar, S; Arasaratnam, V

    2012-09-01

    People rely on the quality of the bottled drinking water, expecting it to be free of microbial contamination and health hazards. To evaluate the quality of bottled drinking water sold in Jaffna peninsula by analysing the physical, chemical and microbial contents and comparing with the recommended Sri Lankan Standard (SLS) values. All bottled water samples sold in Jaffna peninsula were collected. Electrical conductivity, total dissolved solid, pH, calcium, nitrate, total aerobic and anaerobic count, coliform bacterial count and faecal contamination were checked. These are 22 brands of bottled drinking water sold in Jaffna peninsula. The sample had very low electrical conductivity when compared with SLS (750 μS/ cm) and varied from 19 to 253 μS/cm with the mean of 80.53 (±60.92) μS/cm. The pH values of the bottled drinking water brands varied from 4.11 to 7.58 with a mean of 6.2 (±0.75). The total dissolved solid content of the bottled drinking water brands varied from 9 to 123.67 mg/l with a mean of 39.5 (±30.23) mg/l. The calcium content of the bottled drinking water brands varied from 6.48 to 83.77 mg/l with a mean of 49.9 (±25.09) mg/l. The nitrate content of the bottled drinking water brands varied from 0.21 to 4.19 mg/l with the mean of 1.26 (±1.08) mg/l. Aerobic bacterial count varied from 0 to 800 colony forming unit per ml (cfu/ml) with a mean of 262.6 (±327.50) cfu/ml. Among the 22 drinking bottled water brands 14 and 9% of bottled drinking water brands showed fungal and coliform bacterial contaminants respectively. The water brands which contained faecal contamination had either Escherichia coli or Klebsiella spp. The bottled drinking water available for sale do not meet the standards stipulated by SLS.

  7. Exploiting flow injection and sequential injection for trace metal determinations in conjunction with detection by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    Despite their excellent analytical chemical capacities, Electrothermal Atomic Absorption Spectrometry (ETAAS) and Inductively Coupled Plasma Mass Spectrometry (ICPMS), nevertheless, often require suitable pretreatment of the sample material in order to obtain the necessary sensitivity...... and selectivity. Either in order to separate/preconcentrate the analyte material, or because of the presence of potentially interfering matrix constituents. Such pretreatments are advantageously performed in flow injection (FI) or sequential injection (SI) manifolds, where all appropriate unit operations can......, such as liquid-liquid extraction, (co)precipitation with collection in knotted reactors, adsorption, hydride generation, or the use of ion-exchange columns. Apart from hydride generation, where the analyte is converted into a gaseous species, the common denominator for these approaches is that the analyte...

  8. The Closed-Loop Endeavour : A Case Study on Barriers and Enhancements of the PET Bottle-to-Bottle Recycling Systems in Germany and Sweden

    OpenAIRE

    Bayer, Fabian; Bergmann, Jonas

    2016-01-01

    Problem: The demand of beverages in PET bottles is constantly increasing. In this context, environmental, technological and regulatory aspects set a stronger focus on recycling. Generally, the reuse of recycled material from post-consumer PET bottles in bottle-to-bottle applications is seen as least environmentally harmful. However, closed-loop systems are not widely implemented in Europe. Previous research mainly focuses on open-loop recycling systems and generally lacks discussion about the...

  9. Polyelectrolyte complexes of bottle brush copolymers : Solution and adsorption properties

    OpenAIRE

    Alexander, Shovsky

    2011-01-01

    The aim of this thesis work was to systematically investigate the physico-chemical properties of polyelectrolyte complexes (PECs) formed by bottle brush and linear polyelectrolytes in solution and at solid / liquid interfaces. Electrostatic self-assembly of oppositely charged macromolecules in aqueous solution is a versatile strategy to construction of functional nanostructures with easily controlled properties. Bottle brush architecture, introduced into the PEC, generates a number of distinc...

  10. UTILIZATION OF WASTE PLASTIC BOTTLES IN ASPHALT MIXTURE

    OpenAIRE

    TAHER BAGHAEE MOGHADDAM; MOHAMED REHAN KARIM; MEHRTASH SOLTANI

    2013-01-01

    Nowadays, large amounts of waste materials are being produced in the world. One of the waste materials is plastic bottle. Generating disposable plastic bottles is becoming a major problem in many countries. Using waste plastic as a secondary material in construction projects would be a solution to overcome the crisis of producing large amount of waste plastics in one hand and improving the structure’s characteristics such as resistance against cracking on the other hand. This study aimed to i...

  11. Analysis of fluoride concentration in commercial bottled waters

    OpenAIRE

    BIZERRIL,Davi Oliveira; ALMEIDA, Janaína Rocha de Sousa; SALDANHA, Kátia de Góis Holanda; CABRAL FILHO,Ronaldo Emilio; Almeida, Maria Eneide Leitão de

    2015-01-01

    Objective: Evaluate fluoride concentration in 500ml commercial brands of bottled water and compare it to the amount printed on the label. Methods: A descriptive, cross-sectional epidemiological study was conducted. Samples of nine different commercial brands of 500ml bottled water were collected at authorized distribution points in the city of Fortaleza, CE, Brazil, in 2013. Fluoride concentration was determined in duplicate using a fluoride ion-selective electrode. The results were obtain...

  12. Sterilization/disinfection using reduced-pressure plasmas: some differences between direct exposure of bacterial spores to a discharge and their exposure to a flowing afterglow

    Science.gov (United States)

    Moisan, M.; Levif, P.; Séguin, J.; Barbeau, J.

    2014-07-01

    The use of plasma for sterilization or disinfection offers a promising alternative to conventional steam or chemical approaches. Plasma can operate at temperatures less damaging to some heat-sensitive medical devices and, in contrast to chemicals, can be non-toxic and non-polluting for the operator and the environment, respectively. Direct exposure to the gaseous discharge (comprising an electric field and ions/electrons) or exposure to its afterglow (no E-field) can both be envisaged a priori, since these two methods can achieve sterility. However, important issues must be considered besides the sterility goal. Direct exposure to the discharge, although yielding a faster inactivation of microorganisms, is shown to be potentially more aggressive to materials and sometimes subjected to the shadowing effect that precludes the sterilization of complex-form items. These two drawbacks can be successfully minimized with an adequate flowing-afterglow exposure. Most importantly, the current paper shows that direct exposure to the discharge can lead to the dislodgment and release of viable microorganisms from their substratum. Such a phenomenon could be responsible for the recontamination of sterilized devices as well as possible contamination of the ambient surroundings, additionally yielding an erroneous over-appreciation of the inactivation efficiency. The operation of the N2-O2 flowing afterglow system being developed in our group is such that there are no ions and electrons left in the process chamber (late-afterglow regime) in full contrast with their presence in the discharge. The dislodgment and release of spores could be attributed, based on the literature, to their electrostatic charging by electrons, leading to an (outward) electrostatic stress that exceeds the adhesion of the spores on their substrate.

  13. Technical note: Measurement of mammary plasma flow in sows by downstream dilution of mammary vein infused para-aminohippuric acid

    DEFF Research Database (Denmark)

    Larsen, Uffe Krogh; Storm, Adam Christian; Theil, Peter Kappel

    2016-01-01

    catheter was surgically implanted in the femoral artery, and another 2 were inserted in the right cranial mammary vein of 8 second- and third-parity sows on d 76 ± 2 SEM of gestation. On the 3rd and 17th days in milk, arterial and venous blood samples were drawn in hourly intervals from 0.5 h before until...... 6.5 h after feeding. The MPF in the right cranial mammary vein was measured by downstream dilution of infused pAH (3.0 mmol/h). Total MPF-pAH was calculated assuming that the measured flow constituted the flow from 5 out of 14 suckled glands on the basis of the anatomical structure of the mammary...

  14. Final Report for Project DE-SC0006958: "An Investigation of the Effects of magnetic Fields and Collisionality on Shock Formation in Radiatively Cooled Plasma Flows"

    Energy Technology Data Exchange (ETDEWEB)

    Bott-Suzuki, Simon

    2014-11-05

    We have developed a new experimental platform to study bow-shock formation in plasma flows generated using an inverse wire array z-pinch. We have made significant progress on the analysis of both hydrodynamic and magnetized shocks using this system. The hydrodynamic experiments show formation of a well-defined Mach cone, and highly localized shock strong associated with radiative losses and rapidly cooling over the shock. Magnetized shocks show that the balance of magnetic and ram pressures dominate the evolution of the shock region, generating a low plasma beta void around the target. Manuscripts are in preparation for publication on both these topics. We have also published the development of a novel diagnostic method which allow recovery of interferometry and self-emission data along the same line of sight. Finally, we have carried out work to integrate a kinetic routine with the 3D MHD code Gorgon, however it remains to complete this process. Both undergraduate and graduate students have been involved in both the experimental work and publications.

  15. Coating of a substrate with surface preliminarily treated with intensive flows of high-speed electrons and plasma using a magnetron

    Science.gov (United States)

    Leyvi, A. Ya; Yalovets, A. P.

    2017-05-01

    This paper presents results of the research in influence of preliminary surface treatment on adhesion of film to substrate (St8 or brass-target, CU, Ni-film). The preliminary treatment has been conducted by two methods: first, by compressive plasma flow with charge duration ∼100μs, plasma formation rate (15-20)×103 m/s; second, by low-energy high-current electron beams with pulse duration 2-3 μs and electron energy up to 30 keV. The investigation shows the strong influence of preliminary sample treatment and processing parameters on adhesion of film to substrate and final roughness. Experimental investigations have revealed the best adhesion of film to substrate, and the smoothest film is corresponding to the mode with preliminary LEHCEB irradiation with electron energy of 25, 30 keV. It was shown that the alternation of deposition with LEHCEB irradiation has resulted in large-scale surface smoothing: the surface has become glassy whereas craters of 10-20 μm have formed. It was shown that the magnetron-covered samples can withstand the saline mist for twice as long as samples with galvanic coatings.

  16. Ist and IInd elliptic solutions to the extended Grad-Shafranov-Schluter equation for asymmetric tokamak plasma with stationary flows

    Energy Technology Data Exchange (ETDEWEB)

    Zelazny, R.; Stankiewicz, R.; Galkowski, A.; Potempski, S. [Institute of Atomic Energy, Otwock-Swierk (Poland)

    1992-12-31

    The existence of poloidal flow transforms the elliptic Grad-Shafranov-Schluter equation into a system of mixed type partial differential equation (EGSS equation) and an algebraic Bernoulli`s equation. The computer program for solving EGSS equations using inverse method and Fourier decomposition has been prepared. The specific test solutions in the first and second ellipticity regions have been found. (author) 3 refs., 16 figs.

  17. Effects of air bottle design on postural control of firefighters.

    Science.gov (United States)

    Hur, Pilwon; Park, Kiwon; Rosengren, Karl S; Horn, Gavin P; Hsiao-Wecksler, Elizabeth T

    2015-05-01

    The purpose of this study was to investigate the effect of firefighter's self-contained breathing apparatus (SCBA) air bottle design and vision on postural control of firefighters. Twenty-four firefighters were tested using four 30-minute SCBA bottle designs that varied by mass and size. Postural sway measures were collected using a forceplate under two visual conditions (eyes open and closed) and two stance conditions (quiet and perturbed stances). For perturbed stance, a mild backward impulsive pull at the waist was applied. In addition to examining center of pressure postural sway measures for both stance conditions, a robustness measure was assessed for the perturbation condition. The results suggest that wearing heavy bottles significantly increased excursion and randomness of postural sway only in medial-lateral direction but not in anterior-posterior direction. This result may be due to stiffening of plantar-flexor muscles. A significant interaction was obtained between SCBA bottle design and vision in anterior-posterior postural sway, suggesting that wearing heavy and large SCBA air bottles can significantly threaten postural stability in AP direction in the absence of vision. SCBA bottle should be redesigned with reduced weight, smaller height, and COM closer to the body of the firefighters. Firefighters should also widen their stance width when wearing heavy PPE with SCBA. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  18. Polymer based planar coupling of self-assembled bottle microresonators

    Science.gov (United States)

    Grimaldi, I. A.; Berneschi, S.; Testa, G.; Baldini, F.; Nunzi Conti, G.; Bernini, R.

    2014-12-01

    The investigation of a simple and self-assembling method for realizing polymeric micro-bottle resonators is reported. By dispensing precise amounts of SU-8 onto a cleaved optical fiber, employed as mechanical support, bottle microcavities with different shapes and diameters are fabricated. The balancing of surface energy between glass fiber and polymeric microresonator with surface tension of SU-8 confers different shape to these microstructures. Planar single-mode SU-8 based waveguide, realized on polymethylmethacrylate, is chosen for exciting the micro-bottle resonators by evanescent wave. The reliability of the fabrication process and the shape of the bottle microcavities are investigated through optical analysis. We observe whispering gallery modes in these resonant microstructures by a robust coupling with single mode planar waveguides around 1.5 μm wavelength. The resonance spectra of micro-bottle resonators and the spectral characteristics, such as Quality-factor (Q factor) and free spectral range, are evaluated for all the realized microstructures. SU-8 micro-bottle resonators show high Q-factors up to 3.8 × 104 and present a good mechanical stability. These features make these microcavities attractive for sensing and/or lasing applications in a planar platform.

  19. Energy expenditure for breastfeeding and bottle-feeding preterm infants.

    Science.gov (United States)

    Berger, Irit; Weintraub, Valentin; Dollberg, Shaul; Kopolovitz, Rozalia; Mandel, Dror

    2009-12-01

    We hypothesized that resting energy expenditure (REE) would be higher after breastfeeding than after bottle-feeding. Nineteen preterm infants (gestational age: 32 weeks) in stable condition who were nourished entirely with their mothers' breast milk were assigned randomly to feeding either by bottle or at the breast. Each infant served as his or her own control subject. REE was measured for 20 minutes after feeding. Breast milk quantity was evaluated with prefeeding and postfeeding weighing. REE values for bottle-feeding and breastfeeding were compared with paired t tests. Contrary to our null hypothesis, the group's mean REE values after bottle-feeding and breastfeeding were very similar (284.7 +/- 26.8 kJ/kg per day [68.3 +/- 6.4 kcal/kg per day] vs 282.6 +/- 28.5 kJ/kg per day [67.5 +/- 6.8 kcal/kg per day]; not significant). The duration of feeding was significantly longer for breastfeeding than for bottle-feeding (20.1 +/- 7.9 vs 7.8 +/- 2.9 minutes; P bottle-fed. Longer feeding times at the breast did not increase REE. We speculate that it is safe to recommend feeding at the breast for infants born at >32 weeks when they can tolerate oral feeding.

  20. The effectiveness of riboflavin photochemical-mediated virus inactivation and changes in protein retention in fresh-frozen plasma treated using a flow-based treatment device.

    Science.gov (United States)

    Zhu, Liguo; Pan, Jichun; Wei, Chao; Wang, Haibao; Xiang, Rong; Zhang, Jingang; Wang, Deqing

    2015-01-01

    A flow-based treatment device using riboflavin and ultraviolet (UV) light was developed to inactivate viruses in fresh-frozen plasma (FFP). The objective of this study was to evaluate the in vitro effectiveness of virus inactivation and changes in protein quality in FFP treated with this device. FFP-contaminating viruses were treated with riboflavin and UV light using a one-pass linear flow device. The infectivity of viruses was measured using established biologic assays. Real-time polymerase chain reaction (PCR) was performed to detect damage to viral nucleotides after treatment. Treated plasma was analyzed using standard coagulation assays. FFP treated at the UV dose of 3.6 J/cm(2) (J) exhibited a mean reduction of virus titer of more than 4 logs. The effectiveness increased significantly at higher doses. Real-time PCR showed that the cycle threshold values for both complete inactivation and virus recultivation were higher than that of the untreated sample. At doses of 3.6, 5.4, and 7.2 J, the protein recovery rates were 60.2 ± 8.6, 46.6 ± 9.4, and 28.0 ± 1.0% for fibrinogen; 67.0 ± 3.1, 57.3 ± 8.0, and 49.2 ± 3.8% for Factor VIII; 93.6 ± 2.8, 89.6 ± 6.1, and 86.5 ± 5.3% for antithrombin-III; and 72.1 ± 5.6, 59.8 ± 14.2, and 49.2 ± 8.4% for Protein C, respectively. The effectiveness of virus inactivation was enhanced, but total activity of plasma factors was reduced, in a UV dose-dependent manner. © 2014 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.