WorldWideScience

Sample records for approach including plasma

  1. Prediction of the laser-induced plasma characteristics in laser welding: a new modelling approach including a simplified keyhole model

    International Nuclear Information System (INIS)

    The characteristics of the laser-induced plasma encountered in laser welding are investigated using a new three-dimensional modelling approach. A simplified keyhole model is employed to couple with our previous plasma plume model, and thus both the plasma inside a blind keyhole and the plasma plume issuing from the keyhole can be treated simultaneously. Investigations include the effects on the laser-induced plasma characteristics of many factors, including the velocity of metal vapour leaving from the keyhole bottom, the velocity of the shielding gas injected coaxially with the laser beam, the velocity and location of the assisting gas injected laterally with respect to the workpiece, and the energy absorption and radiation heat loss of the laser-induced plasma. Typical computed distributions of temperature, velocity and vapour concentration within the plasma are presented with the continuous-wave CO2 laser welding of iron workpiece as the calculation example. It is shown that the high-temperature core of the laser-induced plasma is mostly located inside the blind keyhole or near the keyhole top for the cases under study. The metal-vapour/shielding-gas momentum ratio plays an important role in determining the height of the plasma plume, and the plume height decreases with increasing shielding-gas velocity. The laterally injected assisting gas may also significantly affect the laser-induced plasma characteristics and thus can be used to control the unfavourable effect of the laser-induced plasma on the laser welding process. The predicted temperatures of the laser-induced plasma are reasonably consistent with corresponding experimental data

  2. Partially ionized plasmas including the third symposium on uranium plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, M. [ed.

    1976-09-01

    Separate abstracts are included for 28 papers on electrically generated plasmas, fission generated plasmas, nuclear pumped lasers, gaseous fuel reactor research, and applications. Five papers have been previously abstracted and included in ERA.

  3. Thermovoltaic semiconductor device including a plasma filter

    Science.gov (United States)

    Baldasaro, Paul F.

    1999-01-01

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

  4. Treatment Options for Plasma Cell Neoplasms (Including Multiple Myeloma)

    Science.gov (United States)

    ... Treatment Health Professional Plasma Cell Neoplasms Treatment Research Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional Version Key ...

  5. Stages of Plasma Cell Neoplasms (Including Multiple Myeloma)

    Science.gov (United States)

    ... Treatment Health Professional Plasma Cell Neoplasms Treatment Research Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional Version Key ...

  6. PREPARATION OF IODINE-INCLUDED CARBON USING RF PLASMA CVD

    Institute of Scientific and Technical Information of China (English)

    Y. Sakamoto; M. Takaya; T. Uchiyama

    2005-01-01

    For the aim of synthesis of the carbon-iodine compound, the preparation of iodine-included carbon using RF plasma CVD was studied. Iodine-included carbon was synthesized on Si substrate using ICP type RF plasma CVD apparatus. C2H5OH and I2 dissolved C2H5OH was used as reactant gases. As a result, surface morphologies of Iodine included carbon films showed fiat surfaces for each samples. On the structure of films estimated by Raman spectroscopy, amorphous carbon was recognized. And I2 peaks were observed in XPS spectra. As a result of friction test,friction coefficient of the sample growth with C2H5OH showed about 0.45. On the other hand,that of the sample with I2-C2H5OH showed about 0.3 and decrease of friction coefficient was recognized. Iodine inclusion for carbon materials can be achieved by RF plasma CVD using an I2-C2H5OH reactant. The coefficient of iodine-included carbon showed lower than of without iodine

  7. Electrode assemblies, plasma apparatuses and systems including electrode assemblies, and methods for generating plasma

    Science.gov (United States)

    Kong, Peter C; Grandy, Jon D; Detering, Brent A; Zuck, Larry D

    2013-09-17

    Electrode assemblies for plasma reactors include a structure or device for constraining an arc endpoint to a selected area or region on an electrode. In some embodiments, the structure or device may comprise one or more insulating members covering a portion of an electrode. In additional embodiments, the structure or device may provide a magnetic field configured to control a location of an arc endpoint on the electrode. Plasma generating modules, apparatus, and systems include such electrode assemblies. Methods for generating a plasma include covering at least a portion of a surface of an electrode with an electrically insulating member to constrain a location of an arc endpoint on the electrode. Additional methods for generating a plasma include generating a magnetic field to constrain a location of an arc endpoint on an electrode.

  8. Plasma stability theory including the resistive wall effects

    Science.gov (United States)

    Pustovitov, V. D.

    2015-12-01

    > Plasma stabilization due to a nearby conducting wall can provide access to better performance in some scenarios in tokamaks. This was proved by experiments with an essential gain in and demonstrated as a long-lasting effect at sufficiently fast plasma rotation in the DIII-D tokamak (see, for example, Strait et al., Nucl. Fusion, vol. 43, 2003, pp. 430-440). The rotational stabilization is the central topic of this review, though eventually the mode rotation gains significance. The analysis is based on the first-principle equations describing the energy balance with dissipation in the resistive wall. The method emphasizes derivation of the dispersion relations for the modes which are faster than the conventional resistive wall modes, but slower than the ideal magnetohydrodynamics modes. Both the standard thin wall and ideal-wall approximations are not valid in this range. Here, these are replaced by an approach incorporating the skin effect in the wall. This new element in the stability theory makes the energy sink a nonlinear function of the complex growth rate. An important consequence is that a mode rotating above a critical level can provide a damping effect sufficient for instability suppression. Estimates are given and applications are discussed.

  9. Experimental approaches for studying non-equilibrium atmospheric plasma jets

    Energy Technology Data Exchange (ETDEWEB)

    Shashurin, A., E-mail: ashashur@purdue.edu [School of Aeronautics & Astronautics, Purdue University, West Lafayette, Indiana 47907 (United States); Keidar, M. [Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, District of Columbia 20052 (United States)

    2015-12-15

    This work reviews recent research efforts undertaken in the area non-equilibrium atmospheric plasma jets with special focus on experimental approaches. Physics of small non-equilibrium atmospheric plasma jets operating in kHz frequency range at powers around few Watts will be analyzed, including mechanism of breakdown, process of ionization front propagation, electrical coupling of the ionization front with the discharge electrodes, distributions of excited and ionized species, discharge current spreading, transient dynamics of various plasma parameters, etc. Experimental diagnostic approaches utilized in the field will be considered, including Rayleigh microwave scattering, Thomson laser scattering, electrostatic streamer scatterers, optical emission spectroscopy, fast photographing, etc.

  10. Alternative approaches to plasma confinement

    Science.gov (United States)

    Roth, J. R.

    1978-01-01

    The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.

  11. Including patients’ perspectives in patient information leaflets: A polyocular approach

    DEFF Research Database (Denmark)

    Fage-Butler, Antoinette Mary

    2013-01-01

    asymmetries. The paper contributes theoretically in its innovative use of perspectivist theory in relation to text, and in identifying that the insights of polyocularity could valuably inform a new health communication paradigm, as current health communication paradigms do not fully recognize patients......Existing research reveals that patients’ perspectives are missing from mandatory patient information leaflets (PILs). At the same time, there is overwhelming consensus that they should be included in this genre, and a corresponding need for potential approaches to tackle this problem. This paper......’ perspectives. Apart from its theoretical contributions, the paper includes guidelines to support the production of PILs where patients’ perspectives are included. The guidelines are informed by practices that have characterised previous polyocular communication events, as well as research into how to maximize...

  12. Research in space science and technology. [including X-ray astronomy and interplanetary plasma physics

    Science.gov (United States)

    Beckley, L. E.

    1977-01-01

    Progress in various space flight research programs is reported. Emphasis is placed on X-ray astronomy and interplanetary plasma physics. Topics covered include: infrared astronomy, long base line interferometry, geological spectroscopy, space life science experiments, atmospheric physics, and space based materials and structures research. Analysis of galactic and extra-galactic X-ray data from the Small Astronomy Satellite (SAS-3) and HEAO-A and interplanetary plasma data for Mariner 10, Explorers 47 and 50, and Solrad is discussed.

  13. 77 FR 6463 - Revisions to Labeling Requirements for Blood and Blood Components, Including Source Plasma...

    Science.gov (United States)

    2012-02-08

    ... 20993-0002, (301) 796-9148. SUPPLEMENTARY INFORMATION: In the FR Doc. 2011-33554, appearing on page 7 in the Federal Register of Tuesday, January 3, 2012 (77 FR 7), the following correction is made: 1. On... Requirements for Blood and Blood Components, Including Source Plasma; Correction AGENCY: Food and...

  14. Relativistic bound state approach to fundamental forces including gravitation

    Directory of Open Access Journals (Sweden)

    Morsch H.P.

    2012-06-01

    Full Text Available To describe the structure of particle bound states of nature, a relativistic bound state formalism is presented, which requires a Lagrangian including scalar coupling of two boson fields. The underlying mechanisms are quite complex and require an interplay of overlapping boson fields and fermion-antifermion production. This gives rise to two potentials, a boson-exchange potential and one identified with the long sought confinement potential in hadrons. With minimal requirements, two elementary massless fermions (quantons - with and without charge - and one gauge boson, hadrons and leptons but also atoms and gravitational systems are described by bound states with electric and magnetic coupling between the charges and spins of quantons. No need is found for colour, Higgs-coupling and supersymmetry.

  15. Including plasma and fusion topics in the science education in school

    International Nuclear Information System (INIS)

    Yutori education (more relaxed education policy) started with the revision of the Courses of Study to introduce 'five-day week system' in 1989, continued with the reduction of the content of school lessons by 30% in 1998, and ended with the introduction of the New Courses of Study in 2011. Focusing on science education, especially in the topics of plasma and nuclear fusion, the modality of the education system in Japan is discussed considering the transition of academic performance based on the Program for International Student Assessment (PISA) in comparison with the examples in other countries. Particularly, the issues with high school textbooks are pointed out from the assessment of current textbooks, and the significance and the need for including the topic of 'plasma' in them are stated. Lastly, in order to make the general public acknowledged with plasma and nuclear fusion, it is suggested to include them also in junior high school textbooks, by briefly mentioning the terms related to plasma, solar wind, aurora phenomenon, and nuclear fusion energy. (S.K.)

  16. A control approach for plasma density in tokamak machines

    Energy Technology Data Exchange (ETDEWEB)

    Boncagni, Luca, E-mail: luca.boncagni@enea.it [EURATOM – ENEA Fusion Association, Frascati Research Center, Division of Fusion Physics, Rome, Frascati (Italy); Pucci, Daniele; Piesco, F.; Zarfati, Emanuele [Dipartimento di Ingegneria Informatica, Automatica e Gestionale ' ' Antonio Ruberti' ' , Sapienza Università di Roma (Italy); Mazzitelli, G. [EURATOM – ENEA Fusion Association, Frascati Research Center, Division of Fusion Physics, Rome, Frascati (Italy); Monaco, S. [Dipartimento di Ingegneria Informatica, Automatica e Gestionale ' ' Antonio Ruberti' ' , Sapienza Università di Roma (Italy)

    2013-10-15

    Highlights: •We show a control approach for line plasma density in tokamak. •We show a control approach for pressure in a tokamak chamber. •We show experimental results using one valve. -- Abstract: In tokamak machines, chamber pre-fill is crucial to attain plasma breakdown, while plasma density control is instrumental for several tasks such as machine protection and achievement of desired plasma performances. This paper sets the principles of a new control strategy for attaining both chamber pre-fill and plasma density regulation. Assuming that the actuation mean is a piezoelectric valve driven by a varying voltage, the proposed control laws ensure convergence to reference values of chamber pressure during pre-fill, and of plasma density during plasma discharge. Experimental results at FTU are presented to discuss weaknesses and strengths of the proposed control strategy. The whole system has been implemented by using the MARTe framework [1].

  17. A variational approach to resistive relativistic plasmas

    CERN Document Server

    Andersson, N; Hawke, I

    2016-01-01

    We develop an action principle to construct the field equations for a multi-fluid system containing charge-neutral fluids, plasmas, and dissipation (via resistive interactions), by combining the standard, Maxwell action and minimal coupling of the electromagnetic field with a recently developed action for relativistic dissipative fluids. We use a pull-back formalism from spacetime to abstract matter spaces to build unconstrained variations for both the charge-neutral fluids and currents making up the plasmas. Using basic linear algebra techniques, we show that a general "relabeling" invariance exists for the abstract matter spaces. With the field equations in place, a phenomenological model for the resistivity is developed, using as constraints charge conservation and the Second Law of Thermodynamics. A minimal model for a system of electrons, protons, and heat is developed using the Onsager procedure for incorporating dissipation.

  18. Langmuir-probe data analysis including the complex nature of the ECR plasma

    International Nuclear Information System (INIS)

    Electron Cyclotron Resonance (ECR) plasmas have already been studied in many ways, mainly by x-ray and UV measurements. Langmuir-probes, however, have proven useful for other kind of plasmas, and have rarely been used to explore the ECR plasma. A diagnostics setup has been built at the 14.5 GHz ATOMKI-ECRIS. Results of the cold plasma region measurements are shown. (R.P.)

  19. Stellarator approach to toroidal plasma confinement

    International Nuclear Information System (INIS)

    An overview is presented of the development and current status of the stellarator approach to controlled thermonuclear confinement. Recent experimental, theoretical, and systems developments have made this concept a viable option for the evolution of the toroidal confinement program. Some experimental study of specific problems associated with departure from two-dimensional symmetry must be undertaken before the full advantages and opportunities of steady-state, net-current-free operation can be realized

  20. Fluorogenic MMP activity assay for plasma including MMPs complexed to α2-macroglobulin

    NARCIS (Netherlands)

    Beekman, B.; Drijfhout, J.W.; Ronday, H.K.; TeKoppele, J.M.

    1999-01-01

    Elevated MMP activities are implicated in tissue degradation in, e.g., arthritis and cancer. The present study was designed to measure MMP enzyme activity in plasma. Free active MMP is unlikely to be present in plasma: upon entering the circulation, active MMP is expected to be captured by the prote

  1. Bifurcation of space-charge wave in a plasma waveguide including the wake potential effect

    Science.gov (United States)

    Lee, Myoung-Jae; Jung, Young-Dae

    2016-09-01

    The wake potential effects on the propagation of the space-charge dust ion-acoustic wave are investigated in a cylindrically bounded dusty plasma with the ion flow. The results show that the wake potential would generate the double frequency modes in a cylindrically bounded dusty plasma. It is found that the upper mode of the wave frequency with the root of higher-order is smaller than that with the root of lower-order in intermediate wave number domains. However, the lower mode of the scaled wave frequency with the root of higher-order is found to be greater than that with the root of lower-order. It is found that the influence in the order of the root of the Bessel function on the wave frequency of the space-charge dust-ion-acoustic wave in a cylindrically confined dusty plasma decreases with an increase in the propagation wave number. It is also found that the double frequency modes increase with increasing Mach number due to the ion flow in a cylindrical dusty plasma. In addition, it is found that the upper mode of the group velocity decreases with an increase in the scaled radius of the plasma cylinder. However, it is shown that the lower mode of the scaled group velocity of the space-charge dust ion acoustic wave increases with an increase in the radius of the plasma cylinder. The variation of the space-charge dust-ion-acoustic wave due to the wake potential and geometric effects is also discussed.

  2. Plasma and oscillations with contributions in memoriam including a complete bibliography of his works

    CERN Document Server

    Suits, C Guy

    1961-01-01

    The Collected Works of Irving Langmuir, Volume 5: Plasma and Oscillations is an 11-chapter text covers the extensive research study of Langmuir in the field of gas discharges. This book specifically tackles oscillations in ionized gases. The opening chapters describe the plasma-boundary phenomena and the use of a probe to separate the primary electron beam from the scattered electrons. The succeeding chapters deal with the collisions between electrons and gas molecules, oscillations in ionized gases, and the interaction of electron and positive ion space charges in cathode sheaths. These t

  3. The postprandial plasma rye fingerprint includes benzoxazinoid-derived phenylacetamide sulfates.

    Science.gov (United States)

    Hanhineva, Kati; Keski-Rahkonen, Pekka; Lappi, Jenni; Katina, Kati; Pekkinen, Jenna; Savolainen, Otto; Timonen, Oskari; Paananen, Jussi; Mykkänen, Hannu; Poutanen, Kaisa

    2014-07-01

    The bioavailability of whole-grain rye-derived phytochemicals has not yet been comprehensively characterized, and different baking and manufacturing processes can modulate the phytochemical composition of breads and other rye products. The aim of our study was to find key differences in the phytochemical profile of plasma after the consumption of 3 breads containing rye bran when compared with a plain white wheat bread control. Plasma metabolite profiles of 12 healthy middle-aged men and women were analyzed using LC quadrupole time-of-flight mass spectrometry metabolomics analysis while fasting and at 60 min, 120 min, 240 min, and 24 h after consuming a meal that contained either 100% whole-grain sourdough rye bread or white wheat bread enriched with native unprocessed rye bran or bioprocessed rye bran. White wheat bread was used as the control. The meals were served in random order after a 12-h overnight fast, with at least 3 d between each occasion. Two sulfonated phenylacetamides, hydroxy-N-(2-hydroxyphenyl) acetamide and N-(2-hydroxyphenyl) acetamide, potentially derived from the benzoxazinoid metabolites, were among the most discriminant postprandial plasma biomarkers distinguishing intake of breads containing whole-meal rye or rye bran from the control white wheat bread. Furthermore, subsequent metabolite profiling analysis of the consumed breads indicated that different bioprocessing/baking techniques involving exposure to microbial metabolism (e.g., sourdough fermentation) have a central role in modulating the phytochemical content of the whole-grain and bran-rich breads.

  4. Control of plasma profile in microwave discharges via inverse-problem approach

    Directory of Open Access Journals (Sweden)

    Yasuyoshi Yasaka

    2013-12-01

    Full Text Available In the manufacturing process of semiconductors, plasma processing is an essential technology, and the plasma used in the process is required to be of high density, low temperature, large diameter, and high uniformity. This research focuses on the microwave-excited plasma that meets these needs, and the research target is a spatial profile control. Two novel techniques are introduced to control the uniformity; one is a segmented slot antenna that can change radial distribution of the radiated field during operation, and the other is a hyper simulator that can predict microwave power distribution necessary for a desired radial density profile. The control system including these techniques provides a method of controlling radial profiles of the microwave plasma via inverse-problem approach, and is investigated numerically and experimentally.

  5. Control of plasma profile in microwave discharges via inverse-problem approach

    Energy Technology Data Exchange (ETDEWEB)

    Yasaka, Yasuyoshi; Tobita, Naoki; Tsuji, Akihiro [Department of Electrical and Electronic Engineering, Kobe University, Kobe 657-8501 (Japan)

    2013-12-15

    In the manufacturing process of semiconductors, plasma processing is an essential technology, and the plasma used in the process is required to be of high density, low temperature, large diameter, and high uniformity. This research focuses on the microwave-excited plasma that meets these needs, and the research target is a spatial profile control. Two novel techniques are introduced to control the uniformity; one is a segmented slot antenna that can change radial distribution of the radiated field during operation, and the other is a hyper simulator that can predict microwave power distribution necessary for a desired radial density profile. The control system including these techniques provides a method of controlling radial profiles of the microwave plasma via inverse-problem approach, and is investigated numerically and experimentally.

  6. 3D MHD VDE and disruptions simulations of tokamaks plasmas including some ITER scenarios

    Science.gov (United States)

    Paccagnella, R.; Strauss, H. R.; Breslau, J.

    2009-03-01

    Tokamaks vertical displacement events (VDEs) and disruptions simulations in toroidal geometry by means of a single fluid visco-resistive magneto-hydro-dynamic (MHD) model are presented in this paper. The plasma model is completed with the presence of a 2D wall with finite resistivity which allows the study of the relatively slowly growing magnetic perturbation, the resistive wall mode (RWM), which is, in this paper, the main drive of the disruption evolution. Amplitudes and asymmetries of the halo currents pattern at the wall are also calculated and comparisons with tokamak experimental databases and predictions for ITER are given.

  7. Transverse instability of ion acoustic solitons in a magnetized plasma including -nonextensive electrons and positrons

    Science.gov (United States)

    Akhtar, N.; El-Taibany, W. F.; Mahmood, S.; Behery, E. E.; Khan, S. A.; Ali, S.; Hussain, S.

    2015-10-01

    > . The magnetic field has no effect on the amplitude of the IASW, whereas the obliqueness angle of the wave propagation, the ion-to-electron temperature ratio and positron-to-ion density concentration ratio affect both the amplitude and the width of the solitary wave structures. The transverse instability analysis illustrates that the one soliton solution has a constant growth rate, and it suffers from instability in the transverse direction. The relevance of the present study to astrophysical space plasmas is also discussed.

  8. Simulation of quiet start magnetized plasmas, including Maxwellian and velocity-space ring distributions

    International Nuclear Information System (INIS)

    Longitudinal electrostatic waves are simulated in a magnetized plasma, propagating perpendicular to B0. Groups of particles are arranged in one or more rings and spokes in velocity space. Using various loading schemes to represent different particle velocity-space distributions in the simulations, f(upsilon/sub perpendicular/), these particles are then distributed uniformly in position space along the length of the system. In particular, the evolution of magnetized cold and warm rings is followed (physically unstable), and of a magnetized Maxwellian (unstable due to the particle loading) through to saturation. Rules are deduced for useful loading methods

  9. Time-Dependent Stochastic Particle Acceleration in Astrophysical Plasmas: Exact Solutions Including Momentum-Dependent Escape

    CERN Document Server

    Becker, P A; Le, T

    2006-01-01

    Stochastic acceleration of charged particles due to interactions with magnetohydrodynamic (MHD) plasma waves is the dominant process leading to the formation of the high-energy electron and ion distributions in a variety of astrophysical systems. Collisions with the waves influence both the energization and the spatial transport of the particles, and therefore it is important to treat these two aspects of the problem in a self-consistent manner. We solve the representative Fokker-Planck equation to obtain a new, closed-form solution for the time-dependent Green's function describing the acceleration and escape of relativistic ions interacting with Alfven or fast-mode waves characterized by momentum diffusion coefficient $D(p)\\propto p^q$ and mean particle escape timescale $t_esc(p) \\propto p^{q-2}$, where $p$ is the particle momentum and $q$ is the power-law index of the MHD wave spectrum. In particular, we obtain solutions for the momentum distribution of the ions in the plasma and also for the momentum dist...

  10. Including the customer in efficiency analysis: evidence of a hybrid relational-transactional approach

    OpenAIRE

    Coughlan, Joseph; Shale, Estelle; Dyson, Robert

    2010-01-01

    Purpose: This paper illustrates the effect of including the customer as a resource in efficiency measurement. Variations in counting the customer illustrate the different impacts on efficiency between a transactional and a relational approach to bank branch marketing. Design/methodology/approach The paper uses Data Envelopment Analysis (DEA) to analyse the efficiency of the branch network under consideration. This technique, while well established in the bank branch eff...

  11. Magnetic field approaches in dc thermal plasma modelling

    Energy Technology Data Exchange (ETDEWEB)

    Freton, P; Gonzalez, J J; Masquere, M [Laplace, UMR 5213 CNRS-UPS-INP, Universite Paul Sabatier, bat 3R2, 118 rte de Narbonne, 31062 Toulouse Cedex (France); Reichert, Frank, E-mail: pierre.freton@laplace.univ-tlse.fr, E-mail: frank.reichert@siemens.com [Siemens AG, E T HP CB PLM R and D B PB, Nonnendammallee 104, 13629 Berlin (Germany)

    2011-08-31

    The self-induced magnetic field has an important role in thermal plasma configurations generated by electric arcs as it generates velocity through Lorentz forces. In the models a good representation of the magnetic field is thus necessary. Several approaches exist to calculate the self-induced magnetic field such as the Maxwell-Ampere formulation, the vector potential approach combined with different kinds of boundary conditions or the Biot and Savart (B and S) formulation. The calculation of the self-induced magnetic field is alone a difficult problem and only few papers of the thermal plasma community speak on this subject. In this study different approaches with different boundary conditions are applied on two geometries to compare the methods and their limitations. The calculation time is also one of the criteria for the choice of the method and a compromise must be found between method precision and computation time. The study shows the importance of the current carrying path representation in the electrode on the deduced magnetic field. The best compromise consists of using the B and S formulation on the walls and/or edges of the calculation domain to determine the boundary conditions and to solve the vector potential in a 2D system. This approach provides results identical to those obtained using the B and S formulation over the entire domain but with a considerable decrease in calculation time.

  12. Including 'positive handling strategies' within training in behaviour management: the 'Team-Teach' approach

    OpenAIRE

    Hayden, Carol; S. Pike

    2005-01-01

    This article reports on aspects of an evaluation of ‘Team-Teach’ - a ‘whole setting holistic’ approach to behaviour management in a range of child-care environments. A distinctive feature of Team-Teach is that it includes both training in de-escalation skills and physical interventions, known as ‘positive handling strategies’. The approach is clearly structured and calibrated against level of risk. It includes accreditation and re-accreditation of trainers. Findings from four case study educa...

  13. Stressors, including social conflict, decrease plasma prolactin in male golden hamsters.

    Science.gov (United States)

    Huhman, K L; Mougey, E H; Moore, T O; Meyerhoff, J L

    1995-12-01

    Following exposure to a stressor, plasma prolactin (PRL) rises in most species. The purpose of the present study was to examine the effect of social conflict or of footshock stress on PRL responsiveness in male Syrian hamsters. Contrary to expectations, PRL was significantly lower in subordinate hamsters than in their dominant opponents or in controls following one, five, or nine exposures to social conflict. Similarly, PRL was reduced in hamsters subjected to a mild footshock stressor. By contrast, adrenocorticotropin, another stress-responsive hormone, was elevated following exposure to each of these stressors. We also demonstrate that PRL release is inhibited by dopamine as it is in other species by showing that there is a dose-dependent increase in PRL release following treatment with the dopamine receptor blocker, domperidone. PMID:8748515

  14. A Reconstruction Approach to High-Order Schemes Including Discontinuous Galerkin for Diffusion

    Science.gov (United States)

    Huynh, H. T.

    2009-01-01

    We introduce a new approach to high-order accuracy for the numerical solution of diffusion problems by solving the equations in differential form using a reconstruction technique. The approach has the advantages of simplicity and economy. It results in several new high-order methods including a simplified version of discontinuous Galerkin (DG). It also leads to new definitions of common value and common gradient quantities at each interface shared by the two adjacent cells. In addition, the new approach clarifies the relations among the various choices of new and existing common quantities. Fourier stability and accuracy analyses are carried out for the resulting schemes. Extensions to the case of quadrilateral meshes are obtained via tensor products. For the two-point boundary value problem (steady state), it is shown that these schemes, which include most popular DG methods, yield exact common interface quantities as well as exact cell average solutions for nearly all cases.

  15. Alcohol intake and colorectal cancer: a comparison of approaches for including repeated measures of alcohol consumption

    DEFF Research Database (Denmark)

    Thygesen, Lau Caspar; Wu, Kana; Grønbaek, Morten;

    2008-01-01

    BACKGROUND: In numerous studies, alcohol intake has been found to be positively associated with colorectal cancer risk. However, the majority of studies included only one exposure measurement, which may bias the results if long-term intake is relevant.METHODS: We compared different approaches...... for including repeated measures of alcohol intake among 47,432 US men enrolled in the Health Professionals Follow-up Study. Questionnaires including questions on alcohol intake had been completed in 1986, 1990, 1994, and 1998. The outcome was incident colorectal cancer during follow-up from 1986 to 2002.RESULTS......: During follow-up, 868 members of the cohort experienced colorectal cancer. Baseline, updated, and cumulative average alcohol intakes were positively associated with colorectal cancer, with only minor differences among the approaches. These results support moderately increased risk for intake >30 g...

  16. Nonextensive statistical mechanics approach to electron trapping in degenerate plasmas

    Science.gov (United States)

    Mebrouk, Khireddine; Gougam, Leila Ait; Tribeche, Mouloud

    2016-06-01

    The electron trapping in a weakly nondegenerate plasma is reformulated and re-examined by incorporating the nonextensive entropy prescription. Using the q-deformed Fermi-Dirac distribution function including the quantum as well as the nonextensive statistical effects, we derive a new generalized electron density with a new contribution proportional to the electron temperature T, which may dominate the usual thermal correction (∼T2) at very low temperatures. To make the physics behind the effect of this new contribution more transparent, we analyze the modifications arising in the propagation of ion-acoustic solitary waves. Interestingly, we find that due to the nonextensive correction, our plasma model allows the possibility of existence of quantum ion-acoustic solitons with velocity higher than the Fermi ion-sound velocity. Moreover, as the nonextensive parameter q increases, the critical temperature Tc beyond which coexistence of compressive and rarefactive solitons sets in, is shifted towards higher values.

  17. An empirical model for the interaction of ultraintense laser pulses with fully ionized plasmas including electrostatic effects

    Science.gov (United States)

    Yang, Jeong-Hoon

    The fast ignitor approach to inertial confinement fusion offers an efficient route to produce higher energy gain for less driver energy and compressed fuel density than the conventional hydrodynamic ignition scheme. Over the last decade, serious efforts have been expended towards the goal of achieving controlled fusion using this new approach. However, until now no simple physical plasma model for this idea has been available and the feasibility of the fast ignition project by petawatt laser pulses is not yet clear. We have investigated the capability of ultrafast lasers with irradiance I > 1018 W cm-2 to produce highly energetic electron beams both in a planar wave and in a Gaussian focus in a low-density plasma and within a physical model of electrostatic effects in relativistic plasmas. The trajectory of a free electron in a plane wave with arbitrary initial conditions has been derived. From the complete solutions for the particle trajectory, we have also determined the initial velocities required to produce figure-of-eight motions for arbitrary initial particle positions. A new expression for the relativistic ponderomotive force has been developed. It compares very well with earlier work by Quesnel and Mora. The new expression promises to speed up particle-in-cell simulations. It has been found that free electrons escape from the Gaussian focal region of a 10-ps petawatt laser pulse very quickly before the field reaches its maximum amplitude. In this case very small net energy transfer occurs during the complete interaction of the electrons with the laser beam, indicating that (in the absence of collective electrostatic effects) free electrons cannot extract enough energy from the ignition laser pulse for ignition. This thesis presents a novel simulation model for predicting the large-scale dynamic behavior of the high intensity laser-plasma interaction. We have developed a simple particle simulation code to explore collective electrostatic effects in plasmas

  18. A structure zone diagram including plasma based deposition and ion etching

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2009-10-14

    An extended structure zone diagram is proposed that includes energetic deposition, characterized by a large flux of ions typical for deposition by filtered cathodic arcs and high power impulse magnetron sputtering. The axes are comprised of a generalized homologous temperature, the normalized kinetic energy flux, and the net film thickness, which can be negative due to ion etching. It is stressed that the number of primary physical parameters affecting growth by far exceeds the number of available axes in such a diagram and therefore it can only provide an approximate and simplified illustration of the growth condition?structure relationships.

  19. An approach to include soil carbon changes in life cycle assessments

    DEFF Research Database (Denmark)

    Petersen, Bjorn Molt; Knudsen, Marie Trydeman; Hermansen, John Erik;

    2013-01-01

    to estimate carbon sequestration to be included in LCA is suggested and applied to two examples where the inclusion of carbon sequestration is especially relevant: 1) Bioenergy: removal of straw from a Danish soil for energy purposes and 2) Organic versus conventional farming: comparative study of soybean......Globally, soil carbon sequestration is expected to hold a major potential to mitigate agricultural greenhouse gas emissions. However, the majority of life cycle assessments (LCA) of agricultural products have not included possible changes in soil carbon sequestration. In the present study, a method...... production in China. The suggested approach considers the time of the soil CO2 emissions for the LCA by including the Bern Carbon Cycle Model. Time perspectives of 20,100 and 200 years are used and a soil depth of 0-100 cm is considered. The application of the suggested method showed that the results were...

  20. New approach to MHD spectral theory of stationary plasma flows

    Science.gov (United States)

    Goedbloed, Hans

    2009-11-01

    The basic equations of MHD spectral theory date back to 1958 for static plasmas (Bernstein et al.) and to 1960 for stationary plasma flows (Frieman and Rotenberg). The number of papers on the two subjects appears to be inversely proportional to their complexity, with the vast majority of contributions to MHD stability of tokamaks being restricted to static equilibria and stationary equilibrium flows mostly being discussed analytically for trivial equilibria or numerically for complicated geometries. The problem with the latter is not that numerical approaches are inaccurate, but that they suffer from lack of analytical guidance concerning the structure of the spectrum. One of the reasons is the usual misnomer of ``non-self adjointness'' of the stationary flow problem. In fact, self-adjointness of the two occurring operators was proved right away. Based on the two quadratic forms corresponding to these operators, (a) we constructed an effective method to compute the eigenvalues in the complex plane, (b) we found the counterpart of the oscillation theorem for eigenvalues of static equilibria (Goedbloed and Sakanaka, 1974) for the eigenvalues of stationary flows, enabling one to map out sequences of eigenvalues in the complex plane. Examples will be given for Rayleigh-Taylor, Kelvin-Helmholtz and magneto-rotational instabilities.

  1. Temperature Control in Spark Plasma Sintering: An FEM Approach

    Directory of Open Access Journals (Sweden)

    G. Molénat

    2010-01-01

    Full Text Available Powder consolidation assisted by pulsed current and uniaxial pressure, namely, Spark Plasma Sintering (SPS, is increasingly popular. One limitation however lies in the difficulty of controlling the sample temperature during compaction. The aim of this work is to present a computational method for the assembly temperature based on the finite elements method (FEM. Computed temperatures have been compared with experimental data for three different dies filled with three materials with different electrical conductivities (TiAl, SiC, Al2O3. The results obtained are encouraging: the difference between computed and experimental values is less than 5%. This allows thinking about this FEM approach as a predictive tool for selecting the right control temperatures in the SPS machine.

  2. Nonlinear Modeling of a High Precision Servo Injection Molding Machine Including Novel Molding Approach

    Institute of Scientific and Technical Information of China (English)

    何雪松; 王旭永; 冯正进; 章志新; 杨钦廉

    2003-01-01

    A nonlinear mathematical model of the injection molding process for electrohydraulic servo injection molding machine (IMM) is developed.It was found necessary to consider the characteristics of asymmetric cylinder for electrohydraulic servo IMM.The model is based on the dynamics of the machine including servo valve,asymmetric cylinder and screw,and the non-Newtonian flow behavior of polymer melt in injection molding is also considered.The performance of the model was evaluated based on novel approach of molding - injection and compress molding,and the results of simulation and experimental data demonstrate the effectiveness of the model.

  3. Electromagnetic microinstabilities in tokamak plasmas using a global spectral approach

    Energy Technology Data Exchange (ETDEWEB)

    Falchetto, G. L

    2002-03-01

    Electromagnetic microinstabilities in tokamak plasmas are studied by means of a linear global eigenvalue numerical code. The code is the electromagnetic extension of an existing electrostatic global gyrokinetic spectral toroidal code, called GLOGYSTO. Ion dynamics is described by the gyrokinetic equation, so that ion finite Larmor radius effects are taken into account to all orders. Non adiabatic electrons are included in the model, with passing particles described by the drift-kinetic equation and trapped particles through the bounce averaged drift-kinetic equation. A low frequency electromagnetic perturbation is applied to a low -but finite- {beta}plasma (where the parameter {beta} identifies the ratio of plasma pressure to magnetic pressure); thus, the parallel perturbations of the magnetic field are neglected. The system is closed by the quasi-neutrality equation and the parallel component of Ampere's law. The formulation is applied to a large aspect ratio toroidal configuration, with circular shifted surfaces. Such a simple configuration enables one to derive analytically the gyrocenter trajectories. The system is solved in Fourier space, taking advantage of a decomposition adapted to the toroidal geometry. The major contributions of this thesis are as follows. The electromagnetic effects on toroidal Ion Temperature Gradient driven (ITG) modes are studied. The stabilization of these modes with increasing {beta}, as predicted in previous work, is confirmed. The inclusion of trapped electron dynamics enables the study of its coupling to the ITG modes and of Trapped Electron Modes (TEM) .The effects of finite {beta} are considered together with those of different magnetic shear profiles and of the Shafranov shift. The threshold for the destabilization of an electromagnetic mode is identified. Moreover, the global formulation yields for the first time the radial structure of this so-called Alfvenic Ion Temperature Gradient (AITG) mode. The stability of the

  4. Effective action approach to wave propagation in scalar QED plasmas

    CERN Document Server

    Shi, Yuan; Qin, Hong

    2016-01-01

    A relativistic quantum field theory with nontrivial background fields is developed and applied to study waves in plasmas. The effective action of the electromagnetic 4-potential is calculated ab initio from the standard action of scalar QED using path integrals. The resultant effective action is gauge invariant and contains nonlocal interactions, from which gauge bosons acquire masses without breaking the local gauge symmetry. To demonstrate how the general theory can be applied, we study a cold unmagnetized plasma and a cold uniformly magnetized plasma. Using these two examples, we show that all linear waves well-known in classical plasma physics can be recovered from relativistic quantum results when taking the classical limit. In the opposite limit, classical wave dispersion relations are modified substantially. In unmagnetized plasmas, longitudinal waves propagate with nonzero group velocities even when plasmas are cold. In magnetized plasmas, anharmonically spaced Bernstein waves persist even when plasma...

  5. An ArcGIS approach to include tectonic structures in point data regionalization.

    Science.gov (United States)

    Darsow, Andreas; Schafmeister, Maria-Theresia; Hofmann, Thilo

    2009-01-01

    Point data derived from drilling logs must often be regionalized. However, aquifers may show discontinuous surface structures, such as the offset of an aquitard caused by tectonic faults. One main challenge has been to incorporate these structures into the regionalization process of point data. We combined ordinary kriging and inverse distance weighted (IDW) interpolation to account for neotectonic structures in the regionalization process. The study area chosen to test this approach is the largest porous aquifer in Austria. It consists of three basins formed by neotectonic events and delimited by steep faults with a vertical offset of the aquitard up to 70 m within very short distances. First, ordinary kriging was used to incorporate the characteristic spatial variability of the aquitard location by means of a variogram. The tectonic faults could be included into the regionalization process by using breaklines with buffer zones. All data points inside the buffer were deleted. Last, IDW was performed, resulting in an aquitard map representing the discontinuous surface structures. This approach enables one to account for such surfaces using the standard software package ArcGIS; therefore, it could be adopted in many practical applications.

  6. Novel pigment approaches in optically variable security inks including polarizing cholesteric liquid crystal (CLC) polymers

    Science.gov (United States)

    Jiang, Yingqiu; Wilson, Robert; Hochbaum, Aharon; Carter, John

    2002-04-01

    Optical variable pigment technologies for markings and inks have increased in use as overt protection methods for document and product security. These technologies use optical reflective effects including interference technologies that create angular dependent color changes. Novel developments in different inorganic and organic pigments offer potentially new optical performance for both overt and covert security applications. These developments may lead to unique signature pigment formats that can verify origin and authenticity. Cholesteric Liquid Crystal (CLC) pigment approaches utilize both angular dependent color flop and the unique polarization properties to potentially develop markings with both overt and covert detection mechanisms. Continuous improvement in these technologies may lead to new visible and non-visible applications that when integrated with the graphic design will provide novel protection and graphic impact.

  7. Modeling weakly-ionized plasmas in magnetic field: A new computationally-efficient approach

    Science.gov (United States)

    Parent, Bernard; Macheret, Sergey O.; Shneider, Mikhail N.

    2015-11-01

    Despite its success at simulating accurately both non-neutral and quasi-neutral weakly-ionized plasmas, the drift-diffusion model has been observed to be a particularly stiff set of equations. Recently, it was demonstrated that the stiffness of the system could be relieved by rewriting the equations such that the potential is obtained from Ohm's law rather than Gauss's law while adding some source terms to the ion transport equation to ensure that Gauss's law is satisfied in non-neutral regions. Although the latter was applicable to multicomponent and multidimensional plasmas, it could not be used for plasmas in which the magnetic field was significant. This paper hence proposes a new computationally-efficient set of electron and ion transport equations that can be used not only for a plasma with multiple types of positive and negative ions, but also for a plasma in magnetic field. Because the proposed set of equations is obtained from the same physical model as the conventional drift-diffusion equations without introducing new assumptions or simplifications, it results in the same exact solution when the grid is refined sufficiently while being more computationally efficient: not only is the proposed approach considerably less stiff and hence requires fewer iterations to reach convergence but it yields a converged solution that exhibits a significantly higher resolution. The combined faster convergence and higher resolution is shown to result in a hundredfold increase in computational efficiency for some typical steady and unsteady plasma problems including non-neutral cathode and anode sheaths as well as quasi-neutral regions.

  8. Spectral line intensities of NeVII for non-equilibrium ionization plasma including dielectronic recombination processes

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Izumi; Kato, Takako [National Inst. for Fusion Science, Toki, Gifu (Japan); Safronova, U.

    1999-01-01

    We have calculated the dielectronic recombination rate coefficients from Li-like Ne (Ne{sup 7+}) ions to Be-like Ne (Ne{sup 6+}) ions for selected excited states of Ne{sup 6+} ions. A collisional-radiative model (CRM) for Ne{sup 6+} ions is constructed to calculate the population density of each excited state in non-equilibrium ionization plasmas, including recombining processes. NeVII spectral line intensities and the radiative power loss are calculated with the CRM. A density effect caused by collisional excitation from the metastable state 2s2p {sup 3}P is found at an electron density of 10{sup 5} - 10{sup 17} cm{sup -3}. The collisional excitations between excited states become important at high electron temperature T{sub e} > or approx. 100 eV. (author)

  9. Spectral line intensities of NeVII for non-equilibrium ionization plasma including dielectronic recombination processes

    International Nuclear Information System (INIS)

    We have calculated the dielectronic recombination rate coefficients from Li-like Ne (Ne7+) ions to Be-like Ne (Ne6+) ions for selected excited states of Ne6+ ions. A collisional-radiative model (CRM) for Ne6+ ions is constructed to calculate the population density of each excited state in non-equilibrium ionization plasmas, including recombining processes. NeVII spectral line intensities and the radiative power loss are calculated with the CRM. A density effect caused by collisional excitation from the metastable state 2s2p 3P is found at an electron density of 105 - 1017 cm-3. The collisional excitations between excited states become important at high electron temperature Te > or approx. 100 eV. (author)

  10. Holographic approach to quark–gluon plasma in heavy ion collisions

    International Nuclear Information System (INIS)

    We review recent applications of the dual holographic approach to describing the quark–gluon plasma observed in high-energy collisions of relativistic heavy nuclei. Holography and AdS/CFT duality provide a means to study the properties of strong-coupling quantum field theories using higher-dimensional gravity theories. The appearance of quark–gluon plasma in heavy ion collisions can be described in dual terms as the formation of a black hole. To illustrate the major achievements of holographic theory, we discuss the calculation of the following quantities: the shear viscosity and other transport coefficients (all calculated by second order hydrodynamic models), the energy dependence of multiplicities, and the anisotropic thermalization and isotropization times. We also compare theoretical predictions with available experimental data, including the recent LHC results. (reviews of topical problems)

  11. Multi-reference approach to the calculation of photoelectron spectra including spin-orbit coupling

    International Nuclear Information System (INIS)

    X-ray photoelectron spectra provide a wealth of information on the electronic structure. The extraction of molecular details requires adequate theoretical methods, which in case of transition metal complexes has to account for effects due to the multi-configurational and spin-mixed nature of the many-electron wave function. Here, the restricted active space self-consistent field method including spin-orbit coupling is used to cope with this challenge and to calculate valence- and core-level photoelectron spectra. The intensities are estimated within the frameworks of the Dyson orbital formalism and the sudden approximation. Thereby, we utilize an efficient computational algorithm that is based on a biorthonormal basis transformation. The approach is applied to the valence photoionization of the gas phase water molecule and to the core ionization spectrum of the [Fe(H2O)6]2+ complex. The results show good agreement with the experimental data obtained in this work, whereas the sudden approximation demonstrates distinct deviations from experiments

  12. Multi-reference approach to the calculation of photoelectron spectra including spin-orbit coupling

    Energy Technology Data Exchange (ETDEWEB)

    Grell, Gilbert; Bokarev, Sergey I., E-mail: sergey.bokarev@uni-rostock.de; Kühn, Oliver [Institut für Physik, Universität Rostock, D-18051 Rostock (Germany); Winter, Bernd; Seidel, Robert [Helmholtz-Zentrum Berlin für Materialien und Energie, Methods for Material Development, Albert-Einstein-Strasse 15, D-12489 Berlin (Germany); Aziz, Emad F. [Helmholtz-Zentrum Berlin für Materialien und Energie, Methods for Material Development, Albert-Einstein-Strasse 15, D-12489 Berlin (Germany); Department of Physics, Freie Universität Berlin, Arnimalle 14, D-14159 Berlin (Germany); Aziz, Saadullah G. [Chemistry Department, Faculty of Science, King Abdulaziz University, 21589 Jeddah (Saudi Arabia)

    2015-08-21

    X-ray photoelectron spectra provide a wealth of information on the electronic structure. The extraction of molecular details requires adequate theoretical methods, which in case of transition metal complexes has to account for effects due to the multi-configurational and spin-mixed nature of the many-electron wave function. Here, the restricted active space self-consistent field method including spin-orbit coupling is used to cope with this challenge and to calculate valence- and core-level photoelectron spectra. The intensities are estimated within the frameworks of the Dyson orbital formalism and the sudden approximation. Thereby, we utilize an efficient computational algorithm that is based on a biorthonormal basis transformation. The approach is applied to the valence photoionization of the gas phase water molecule and to the core ionization spectrum of the [Fe(H{sub 2}O){sub 6}]{sup 2+} complex. The results show good agreement with the experimental data obtained in this work, whereas the sudden approximation demonstrates distinct deviations from experiments.

  13. Multi-reference approach to the calculation of photoelectron spectra including spin-orbit coupling

    CERN Document Server

    Grell, Gilbert; Winter, Bernd; Seidel, Robert; Aziz, Emad F; Aziz, Saadullah G; Kühn, Oliver

    2015-01-01

    X-ray photoelectron spectra provide a wealth of information on the electronic structure. The extraction of molecular details requires adequate theoretical methods, which in case of transition metal complexes has to account for effects due to the multi-configurational and spin-mixed nature of the many-electron wave function. Here, the Restricted Active Space Self-Consistent Field method including spin-orbit coupling is used to cope with this challenge and to calculate valence and core photoelectron spectra. The intensities are estimated within the frameworks of the Dyson orbital formalism and the sudden approximation. Thereby, we utilize an efficient computational algorithm that is based on a biorthonormal basis transformation. The approach is applied to the valence photoionization of the gas phase water molecule and to the core ionization spectrum of the $\\text{[Fe(H}_2\\text{O)}_6\\text{]}^{2+}$ complex. The results show good agreement with the experimental data obtained in this work, whereas the sudden approx...

  14. New approach to magnetohydrodynamics spectral theory of stationary plasma flows

    NARCIS (Netherlands)

    Goedbloed, J. P.

    2011-01-01

    While the basic equations of MHD spectral theory date back to 1958 for static plasmas (Bernstein et al 1958 Proc. R. Soc. A 244 17) and to 1960 for stationary plasma flows (Frieman and Rotenberg 1960 Rev. Mod. Phys. 32 898), progress on the latter subject has been slow since it suffers from lack of

  15. Zooming of states and parameters using a lumping approach including back-translation

    Directory of Open Access Journals (Sweden)

    Jirstrand Mats

    2010-03-01

    Full Text Available Abstract Background Systems biology models tend to become large since biological systems often consist of complex networks of interacting components, and since the models usually are developed to reflect various mechanistic assumptions of those networks. Nevertheless, not all aspects of the model are equally interesting in a given setting, and normally there are parts that can be reduced without affecting the relevant model performance. There are many methods for model reduction, but few or none of them allow for a restoration of the details of the original model after the simplified model has been simulated. Results We present a reduction method that allows for such a back-translation from the reduced to the original model. The method is based on lumping of states, and includes a general and formal algorithm for both determining appropriate lumps, and for calculating the analytical back-translation formulas. The lumping makes use of efficient methods from graph-theory and ϵ-decomposition and is derived and exemplified on two published models for fluorescence emission in photosynthesis. The bigger of these models is reduced from 26 to 6 states, with a negligible deviation from the reduced model simulations, both when comparing simulations in the states of the reduced model and when comparing back-translated simulations in the states of the original model. The method is developed in a linear setting, but we exemplify how the same concepts and approaches can be applied to non-linear problems. Importantly, the method automatically provides a reduced model with back-translations. Also, the method is implemented as a part of the systems biology toolbox for matlab, and the matlab scripts for the examples in this paper are available in the supplementary material. Conclusions Our novel lumping methodology allows for both automatic reduction of states using lumping, and for analytical retrieval of the original states and parameters without performing a

  16. Unified model to the Tungsten inert Gas welding process including the cathode, the plasma and the anode

    International Nuclear Information System (INIS)

    During this work, a 2D axially symmetric model of a TIG arc welding process had been developed in order to predict for given welding parameters, the needed variables for a designer of welded assembly: the heat input on the work piece, the weld pool geometry,... The developed model, using the Cast3M finite elements software, deals with the physical phenomena acting in each part of the process: the cathode, the plasma, the work piece with a weld pool, and the interfaces between these parts. To solve this model, the thermohydraulics equations are coupled with the electromagnetic equations that are calculated in part using the least squares finite element method. The beginning of the model validation consisted in comparing the results obtained with the ones available in the scientific literature. Thus, this step points out the action of each force in the weld pool, the contribution of each heat flux in the energy balance. Finally, to validate the model predictiveness, experimental and numerical sensitivity analyses were conducted using a design of experiments approach. The effects of the process current, the arc gap and the electrode tip angle on the weld pool geometry and the energy transferred to the work piece and the arc efficiency were studied. The good agreement obtained by the developed model for these outputs shows the good reproduction of the process physics. (author)

  17. Plasma Onco-Immunotherapy: Novel Approach to Cancer Treatment

    Science.gov (United States)

    Fridman, Alexander

    2015-09-01

    Presentation is reviewing the newest results obtained by researchers of A.J. Drexel Plasma Institute on direct application of non-thermal plasma for direct treatment of different types of cancer by means of specific stimulation of immune system in the frameworks of the so-called onco-immunotherapy. Especial attention is paid to analysis of depth of penetration of different plasma-medical effects, from ROS, RNS, and ions to special biological signaling and immune system related processes. General aspects of the plasma-stimulation of immune system are discussed, pointing out specific medical applications. Most of experiments have been carried out using nanosecond pulsed DBD at low power and relatively low level of treatment doses, guaranteeing non-damage no-toxicity treatment regime. The nanosecond pulsed DBD physics is discussed mostly regarding its space uniformity and control of plasma parameters relevant to plasma medical treatment, and especially relevant to depth of penetration of different plasma medical effects. Detailed mechanism of the plasma-induced onco-immunotherapy has been suggested based upon preliminary in-vitro experiments with DBD treatment of different cancer cells. Sub-elements of this mechanism related to activation of macrophages and dendritic cells, specific stressing of cancer cells and the immunogenic cell death (ICD) are to be discussed based on results of corresponding in-vitro experiments. In-vivo experiments focused on the plasma-induced onco-immunotherapy were carried out in collaboration with medical doctors from Jefferson University hospital of Philadelphia. Todays achievements and nearest future prospective of clinical test focused on plasma-controlled cancer treatment are discussed in conclusion.

  18. A decision support system prototype including human factors based on the TOGA meta-theory approach

    International Nuclear Information System (INIS)

    The human contribution to the risk of operation of complex technological systems is often not negligible and sometimes tends to become significant, as shown by many reports on incidents and accidents occurred in the past inside Nuclear Power Plants (NPPs). An error of a human operator of a NPP can derive by both omission and commission. For instance, complex commission errors can also lead to significant catastrophic technological accidents, as for the case of the Three Mile Island accident. Typically, the problem is analyzed by focusing on the single event chain that has provoked the incident or accident. What is needed is a general framework able to include as many parameters as possible, i.e. both technological and human factors. Such a general model could allow to envisage an omission or commission error before it can happen or, alternatively, suggest preferred actions to do in order to take countermeasures to neutralize the effect of the error before it becomes critical. In this paper, a preliminary Decision Support System (DSS) based on the so-called (-) TOGA meta-theory approach is presented. The application of such a theory to the management of nuclear power plants has been presented in the previous ICAPP 2011. Here, a human factor simulator prototype is proposed in order to include the effect of human errors in the decision path. The DSS has been developed using a TRIGA research reactor as reference plant, and implemented using the LabVIEW programming environment and the Finite State Machine (FSM) model The proposed DSS shows how to apply the Universal Reasoning Paradigm (URP) and the Universal Management Paradigm (UMP) to a real plant context. The DSS receives inputs from instrumentation data and gives as output a suggested decision. It is obtained as the result of an internal elaborating process based on a performance function. The latter, describes the degree of satisfaction and efficiency, which are dependent on the level of responsibility related to

  19. Promoting Plasma Physics as a Career: A Generational Approach

    Science.gov (United States)

    Morgan, James

    2005-10-01

    A paradigm shift is occurring in education physics programs. Educators are shifting from the traditional teaching focus to concentrate on student learning. Students are unaware of physics as a career, plasma physics or the job opportunities afforded to them with a physics degree. The physics profession needs to promote itself to the younger generations, or specifically the millennial generation (Born in the 1980's-2000's). Learning styles preferred by ``Millennials'' include a technological environment that promotes learning through active task performance rather than passive attendance at lectures. Millennials respond well to anything experiential and will be motivated by opportunities for creativity and challenging learning environments. The open-ended access to information, the ability to tailor learning paths, and continuous and instantaneous performance assessment offer flexibility in the design of curricula as well as in the method of delivery. Educators need to understand the millennial generation, appeal to their motivations and offer a learning environment designed for their learning style. This poster suggests promoting a physics career by focusing on generational learning styles and preferences.

  20. A nonextensive statistics approach for Langmuir waves in relativistic plasmas

    Directory of Open Access Journals (Sweden)

    V. Muñoz

    2006-01-01

    Full Text Available The nonextensive statistics formalism proposed by Tsallis has found many applications in systems with memory effects, long range spatial correlations, and in general whenever the phase space has fractal or multi-fractal structure. These features may appear naturally in turbulent or non-neutral plasmas. In fact, the equilibrium distribution functions which maximize the nonextensive entropy strongly resemble the non-Maxwellian particle distribution functions observed in space and laboratory and turbulent pure electron plasmas. In this article we apply the Tsallis entropy formalism to the problem of longitudinal oscillations in a proton-electron plasma. In particular, we study the equilibrium distribution function and the dispersion relation of longitudinal oscillations in a relativistic plasma, finding interesting differences with the nonrelativistic treatment.

  1. Klotho: a humeral mediator in CSF and plasma that influences longevity and susceptibility to multiple complex disorders, including depression

    Science.gov (United States)

    Pavlatou, M G; Remaley, A T; Gold, P W

    2016-01-01

    Klotho is a hormone secreted into human cerebrospinal fluid (CSF), plasma and urine that promotes longevity and influences the onset of several premature senescent phenotypes in mice and humans, including atherosclerosis, cardiovascular disease, stroke and osteoporosis. Preliminary studies also suggest that Klotho possesses tumor suppressor properties. Klotho's roles in these phenomena were first suggested by studies demonstrating that a defect in the Klotho gene in mice results in a significant decrease in lifespan. The Klotho-deficient mouse dies prematurely at 8–9 weeks of age. At 4–5 weeks of age, a syndrome resembling human ageing emerges consisting of atherosclerosis, osteoporosis, cognitive disturbances and alterations of hippocampal architecture. Several deficits in Klotho-deficient mice are likely to contribute to these phenomena. These include an inability to defend against oxidative stress in the central nervous system and periphery, decreased capacity to generate nitric oxide to sustain normal endothelial reactivity, defective Klotho-related mediation of glycosylation and ion channel regulation, increased insulin/insulin-like growth factor signaling and a disturbed calcium and phosphate homeostasis accompanied by altered vitamin D levels and ectopic calcification. Identifying the mechanisms by which Klotho influences multiple important pathways is an emerging field in human biology that will contribute significantly to understanding basic physiologic processes and targets for the treatment of complex diseases. Because many of the phenomena seen in Klotho-deficient mice occur in depressive illness, major depression and bipolar disorder represent illnesses potentially associated with Klotho dysregulation. Klotho's presence in CSF, blood and urine should facilitate its study in clinical populations. PMID:27576165

  2. Differential partitioning of antioxidants, including hydroxytyrosol, in human plasma and LDL: implications for their antioxidant activity in vivo.

    Science.gov (United States)

    Visioli, Francesco; Colombo, Claudio; Galli, Claudio

    2012-05-01

    In vivo studies of LDL oxidation following consumption of natural phenolic compounds have yielded mixed results. It is reported that the amphiphilic hydroxytyrosol, after addition to human plasma, does not accumulate in LDL but protects plasma lipids, which are extracted together with hydroxytyrosol, from chemically-induced oxidation. Thus, a novel methodology was proposed, which does not rely on LDL separation and subsequent oxidation but is based on the oxidation of total lipids - simultaneously extracted from plasma with antioxidants - to evaluate the effects of micronutrients that do not partition into LDL, after in vivo supplementation.

  3. FENICIA: a generic plasma simulation code using a flux-independent field-aligned coordinate approach

    International Nuclear Information System (INIS)

    The primary thrust of this work is the development and implementation of a new approach to the problem of field-aligned coordinates in magnetized plasma turbulence simulations called the FCI approach (Flux-Coordinate Independent). The method exploits the elongated nature of micro-instability driven turbulence which typically has perpendicular scales on the order of a few ion gyro-radii, and parallel scales on the order of the machine size. Mathematically speaking, it relies on local transformations that align a suitable coordinate to the magnetic field to allow efficient computation of the parallel derivative. However, it does not rely on flux coordinates, which permits discretizing any given field on a regular grid in the natural coordinates such as (x, y, z) in the cylindrical limit. The new method has a number of advantages over methods constructed starting from flux coordinates, allowing for more flexible coding in a variety of situations including X-point configurations. In light of these findings, a plasma simulation code FENICIA has been developed based on the FCI approach with the ability to tackle a wide class of physical models. The code has been verified on several 3D test models. The accuracy of the approach is tested in particular with respect to the question of spurious radial transport. Tests on 3D models of the drift wave propagation and of the Ion Temperature Gradient (ITG) instability in cylindrical geometry in the linear regime demonstrate again the high quality of the numerical method. Finally, the FCI approach is shown to be able to deal with an X-point configuration such as one with a magnetic island with good convergence and conservation properties. (author)

  4. Viscous quark-gluon plasma model through fluid QCD approach

    Energy Technology Data Exchange (ETDEWEB)

    Djun, T. P., E-mail: tpdjun@teori.fisika.lipi.go.id [Graduate Study in Material Science, University of Indonesia, Kampus UI Salemba, Jakarta 10430, Indonesia and Group for Theoretical and Computational Physics, Research Center for Physics, Indonesian Institute of Sciences, Kompleks Puspiptek Serpong, T (Indonesia); Soegijono, B.; Mart, T. [Graduate Study in Material Science, University of Indonesia, Kampus UI Salemba, Jakarta 10430, Indonesia and Department of Physics, University of Indonesia, Kampus UI Depok, Depok 16424 (Indonesia); Handoko, L. T., E-mail: Handoko@teorifisika.lipi.go.id, E-mail: Laksana.tri.handoko@lipi.go.id [Group for Theoretical and Computational Physics, Research Center for Physics, Indonesian Institute of Sciences, Kompleks Puspiptek Serpong, Tangerang 15310, Indonesia and Research Center for Informatics, Indonesia Institute of Sciences, Kompleks LIPI (Indonesia)

    2014-09-25

    A Lagrangian density for viscous quark-gluon plasma has been constructed within the fluid-like QCD framework. Gauge symmetry is preserved for all terms inside the Lagrangian, except for the viscous term. The transition mechanism from point particle field to fluid field, and vice versa, are discussed. The energy momentum tensor that is relevant to the gluonic plasma having the nature of fluid bulk of gluon sea is derived within the model. By imposing conservation law in the energy momentum tensor, shear viscosity appears as extractable from the equation.

  5. A nonlinear generalized continuum approach for electro-elasticity including scale effects

    Science.gov (United States)

    Skatulla, S.; Arockiarajan, A.; Sansour, C.

    2009-01-01

    Materials characterized by an electro-mechanically coupled behaviour fall into the category of so-called smart materials. In particular, electro-active polymers (EAP) recently attracted much interest, because, upon electrical loading, EAP exhibit a large amount of deformation while sustaining large forces. This property can be utilized for actuators in electro-mechanical systems, artificial muscles and so forth. When it comes to smaller structures, it is a well-known fact that the mechanical response deviates from the prediction of classical mechanics theory. These scale effects are due to the fact that the size of the microscopic material constituents of such structures cannot be considered to be negligible small anymore compared to the structure's overall dimensions. In this context so-called generalized continuum formulations have been proven to account for the micro-structural influence to the macroscopic material response. Here, we want to adopt a strain gradient approach based on a generalized continuum framework [Sansour, C., 1998. A unified concept of elastic-viscoplastic Cosserat and micromorphic continua. J. Phys. IV Proc. 8, 341-348; Sansour, C., Skatulla, S., 2007. A higher gradient formulation and meshfree-based computation for elastic rock. Geomech. Geoeng. 2, 3-15] and extend it to also encompass the electro-mechanically coupled behaviour of EAP. The approach introduces new strain and stress measures which lead to the formulation of a corresponding generalized variational principle. The theory is completed by Dirichlet boundary conditions for the displacement field and its derivatives normal to the boundary as well as the electric potential. The basic idea behind this generalized continuum theory is the consideration of a micro- and a macro-space which together span the generalized space. As all quantities are defined in this generalized space, also the constitutive law, which is in this work conventional electro-mechanically coupled nonlinear

  6. Transitions between the different regimes of propagation of an electron plasma wave, including the effect of Landau damping, trapping and plasma inhomogeneity

    CERN Document Server

    Bénisti, Didier

    2016-01-01

    This paper addresses the linear and nonlinear propagation of an electron wave (EPW), in a three-dimensional geometry, and in a collisionless plasma that may be inhomogeneous, nonstationary, anisotropic and even weakly magnetized. The wave amplitude, together with any hydrodynamic quantity characterizing the plasma (density, temperature,...) are supposed to vary very little within one wavelength or one wave period. Hence, the geometrical optics limit is assumed, and the wave propagation is described by a first order differential equation. This equation explicitly accounts for three-dimensional effects, plasma inhomogeneity, Landau damping, and the collisionless dissipation and electron acceleration due to trapping. It is derived by mixing results obtained from a direct resolution of the Vlasov-Poisson system and from a variational formalism involving a nonlocal Lagrangian density. In a one-dimensional situation, abrupt transitions are predicted in the coefficients of the wave equation. They occur when the sate...

  7. Phase-field approach to polycrystalline solidification including heterogeneous and homogeneous nucleation

    Energy Technology Data Exchange (ETDEWEB)

    Pusztai, Tamas; Toth, Gyula I; Koernyei, Laszlo [Research Institute for Solid State Physics and Optics, PO Box 49, H-1525 Budapest (Hungary); Tegze, Gyoergy; Bansel, Gurvinder; Fan, Zhungyun; Granasy, Laszlo [Brunel Centre for Advanced Solidification Technology, Brunel University, Uxbridge UB8 3PH (United Kingdom)], E-mail: Laszlo.Granasy@brunel.ac.uk, E-mail: grana@szfki.hu

    2008-10-08

    Advanced phase-field techniques have been applied to address various aspects of polycrystalline solidification including different modes of crystal nucleation. The height of the nucleation barrier has been determined by solving the appropriate Euler-Lagrange equations. The examples shown include the comparison of various models of homogeneous crystal nucleation with atomistic simulations for the single-component hard sphere fluid. Extending previous work for pure systems (Granasy et al 2007 Phys. Rev. Lett. 98 035703), heterogeneous nucleation in unary and binary systems is described via introducing boundary conditions that realize the desired contact angle. A quaternion representation of crystallographic orientation of the individual particles (outlined in Pusztai et al 2005 Europhys. Lett. 71 131) has been applied for modeling a broad variety of polycrystalline structures including crystal sheaves, spherulites and those built of crystals with dendritic, cubic, rhombo-dodecahedral and truncated octahedral growth morphologies. Finally, we present illustrative results for dendritic polycrystalline solidification obtained using an atomistic phase-field model.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-10-15

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

  9. Some Geometric Evolution Equations Arising as Geodesic Equations on Groups of Diffeomorphisms Including the Hamiltonian Approach

    OpenAIRE

    Michor, Peter W.

    2006-01-01

    This is the extended version of a lecture course given at the University of Vienna in the spring term 2005. The main aim of this course was to understand the papers \\cite{10} and \\cite{11} and to give a complete account of existence and uniqueness of the solutions of the members of higher order of the hierarchies of Burgers' equation and the Korteweg-de Vries equation, including their derivation and all the necessary background, both on the circle and on the real line in the setting of rapidl...

  10. Including the monetary part in macro accounting: A ‘modern’ approach to the macroeconomic accounting

    Directory of Open Access Journals (Sweden)

    Onur TUTULMAZ

    2014-12-01

    Full Text Available Economic output is placed at the heart of the macroeconomics. To calculate the output one needs to achieve simplifying a high level complexity of economic relationships to form a system. On the flip side, the model should be enough elaborated to be able to reflect the important relationships. In this manner, the classical macroeconomic identity as Keynes suggested is simple enough to understand the main elements but it does not show the financial parts of transactions. Not having the monetary part of the economy it lacks the coherence. With the financial and economic crises getting more frequent, more endeavour to build a more inclusive and coherent macroeconomic system has been observed. However, there are large variety in different options of simplifying and simulating complex relationships among the real and monetary part of the modern economies.  Our paper tries to set an analysis comparing some of the recent prominent ideas in building balance sheet and transaction flow matrix in regard to macroeconomic accounting system. We can conclude the new achievement of including the monetary transactions in the frame causes a compromise from the simplicity for a coherent and more complete picture of macro economy.

  11. Coherent dynamic structure factors of strongly coupled plasmas: A generalized hydrodynamic approach

    Science.gov (United States)

    Luo, Di; Zhao, Bin; Hu, GuangYue; Gong, Tao; Xia, YuQing; Zheng, Jian

    2016-05-01

    A generalized hydrodynamic fluctuation model is proposed to simplify the calculation of the dynamic structure factor S(ω, k) of non-ideal plasmas using the fluctuation-dissipation theorem. In this model, the kinetic and correlation effects are both included in hydrodynamic coefficients, which are considered as functions of the coupling strength (Γ) and collision parameter (kλei), where λei is the electron-ion mean free path. A particle-particle particle-mesh molecular dynamics simulation code is also developed to simulate the dynamic structure factors, which are used to benchmark the calculation of our model. A good agreement between the two different approaches confirms the reliability of our model.

  12. Stability of three-dimensional obliquely propagating dust acoustic waves in dusty plasma including the polarization force effect

    Science.gov (United States)

    El-Labany, S. K.; El-Taibany, W. F.; Behery, E. E.; Zedan, N. A.

    2015-12-01

    Propagation of dust acoustic solitary waves (DASWs) in a magnetized dusty plasma consisting of extremely massive, negatively/positively charged dust fluid and Boltzmann distributed electrons and ions is studied. A nonlinear Zakharov-Kuznetsov (ZK) equation adequate for describing the solitary waves is derived by applying a reductive perturbation technique. Moreover, an extended Zakharov Kuznetsov (EZK) equation is derived at the vicinity of the critical phase velocity. The effects of the polarization force are explicitly discussed and the growth rate of the produced waves is calculated. It is found that the physical parameters have strong effects on the instability criterion as well as on the growth rate. It is noted that the phase velocity decreases as the polarization force, the effective-to-ion temperature ratio, and the ion-to-electron temperature ratio increase. Moreover, the nonlinearity coefficient and the critical phase velocity increase by increasing the polarization force. The relevance of these findings to a recent plasma experiment and astrophysical plasma observations is briefly discussed.

  13. New approach to magnetohydrodynamics spectral theory of stationary plasma flows

    Science.gov (United States)

    (Hans Goedbloed, J. P.

    2011-07-01

    While the basic equations of MHD spectral theory date back to 1958 for static plasmas (Bernstein et al 1958 Proc. R. Soc. A 244 17) and to 1960 for stationary plasma flows (Frieman and Rotenberg 1960 Rev. Mod. Phys. 32 898), progress on the latter subject has been slow since it suffers from lack of analytical insight concerning the structure of the spectrum. One of the reasons is the usual misnomer of 'non-self adjointness' of the stationary flow problem. Actually, self-adjointness of the occurring operators, namely the generalized force operator and the Doppler-Coriolis gradient operator -iρv·∇, was proved right away by Frieman and Rotenberg. Based on the reality of the two quadratic forms corresponding to these operators, we here construct (a) an effective method to compute the solution paths in the complex ω plane on which the eigenvalues are situated, (b) the counterpart of the oscillation theorem for eigenvalues of static equilibria (Goedbloed and Sakanaka 1974 Phys. Fluids 17 908) for the eigenvalues of stationary flows, based on the monotonicity of the alternating ratio, or alternator, of the boundary values of the displacement ξ and the total pressure perturbation Π. This enables one to map out the complete spectrum of eigenvalues in the complex ω-plane. The intricate topology of the solution paths is discussed for the fundamental examples of Rayleigh-Taylor, Kelvin-Helmholtz and combined instabilities.

  14. New approach to magnetohydrodynamics spectral theory of stationary plasma flows

    Energy Technology Data Exchange (ETDEWEB)

    Goedbloed, J P, E-mail: goedbloed@rijnh.nl [FOM-Institute for Plasma Physics ' Rijnhuizen' , Nieuwegein (Netherlands); Astronomical Institute, Utrecht University (Netherlands)

    2011-07-15

    While the basic equations of MHD spectral theory date back to 1958 for static plasmas (Bernstein et al 1958 Proc. R. Soc. A 244 17) and to 1960 for stationary plasma flows (Frieman and Rotenberg 1960 Rev. Mod. Phys. 32 898), progress on the latter subject has been slow since it suffers from lack of analytical insight concerning the structure of the spectrum. One of the reasons is the usual misnomer of 'non-self adjointness' of the stationary flow problem. Actually, self-adjointness of the occurring operators, namely the generalized force operator and the Doppler-Coriolis gradient operator -i{rho}v{center_dot}{nabla}, was proved right away by Frieman and Rotenberg. Based on the reality of the two quadratic forms corresponding to these operators, we here construct (a) an effective method to compute the solution paths in the complex {omega} plane on which the eigenvalues are situated, (b) the counterpart of the oscillation theorem for eigenvalues of static equilibria (Goedbloed and Sakanaka 1974 Phys. Fluids 17 908) for the eigenvalues of stationary flows, based on the monotonicity of the alternating ratio, or alternator, of the boundary values of the displacement {xi} and the total pressure perturbation {Pi}. This enables one to map out the complete spectrum of eigenvalues in the complex {omega}-plane. The intricate topology of the solution paths is discussed for the fundamental examples of Rayleigh-Taylor, Kelvin-Helmholtz and combined instabilities. (topical review)

  15. A systematic review of pedagogical approaches that can effectively include children with special educational needs in mainstream classrooms with a particular focus on peer group interactive approaches

    OpenAIRE

    Nind, M.; Wearmouth, J.; Collins, J.; Hall, K; Rix, J.; Sheehy, K.

    2004-01-01

    The broad background to this review is a long history of concepts of special pupils and special education, and a faith in special pedagogical approaches. The rise of inclusive schools and some important critiques of special pedagogy (e.g. Hart, 1996; Norwich and Lewis, 2001; Thomas and Loxley, 2001) have raised the profile of teaching approaches that ordinary teachers can and do use to include children with special educational needs in mainstream classrooms. Inclusive education itself is incr...

  16. A systematic review of pedagogical approaches that can effectively include children with special educational needs in mainstream classrooms with a particular focus on peer group interactive approaches

    OpenAIRE

    Nind, Melanie; Wearmouth, Janice

    2005-01-01

    Background The broad background to this review is a long history of concepts of special pupils and special education and a faith in special pedagogical approaches. The rise of inclusive schools and some important critiques of special pedagogy (e.g. Hart, 1996; Norwich and Lewis, 2001; Thomas and Loxley, 2001) have raised the profile of teaching approaches that ordinary teachers can and do use to include children with special educational needs in mainstream classrooms. Inclusive education i...

  17. Novel rapid liquid chromatography tandem masspectrometry method for vemurafenib and metabolites in human plasma, including metabolite concentrations at steady state.

    Science.gov (United States)

    Vikingsson, Svante; Strömqvist, Malin; Svedberg, Anna; Hansson, Johan; Höiom, Veronica; Gréen, Henrik

    2016-08-01

    A novel, rapid and sensitive liquid chromatography tandem-mass spectrometry method for quantification of vemurafenib in human plasma, that also for the first time allows for metabolite semi-quantification, was developed and validated to support clinical trials and therapeutic drug monitoring. Vemurafenib was analysed by precipitation with methanol followed by a 1.9 min isocratic liquid chromatography tandem masspectrometry analysis using an Acquity BEH C18 column with methanol and formic acid using isotope labelled internal standards. Analytes were detected in multireaction monitoring mode on a Xevo TQ. Semi-quantification of vemurafenib metabolites was performed using the same analytical system and sample preparation with gradient elution. The vemurafenib method was successfully validated in the range 0.5-100 μg/mL according to international guidelines. The metabolite method was partially validated owing to the lack of commercially available reference materials. For the first time concentration levels at steady state for melanoma patients treated with vemurafenib is presented. The low abundance of vemurafenib metabolites suggests that they lack clinical significance. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26683023

  18. A statistical approach for predicting thermal diffusivity profiles in fusion plasmas as a transport model

    International Nuclear Information System (INIS)

    A statistical approach is proposed to predict thermal diffusivity profiles as a transport “model” in fusion plasmas. It can provide regression expressions for the ion and electron heat diffusivities (χi and χe), separately, to construct their radial profiles. An approach that this letter is proposing outstrips the conventional scaling laws for the global confinement time (τE) since it also deals with profiles (temperature, density, heating depositions etc.). This approach has become possible with the analysis database accumulated by the extensive application of the integrated transport analysis suite to experiment data. In this letter, TASK3D-a analysis database for high-ion-temperature (high-Ti) plasmas in the LHD (Large Helical Device) is used as an example to describe an approach. (author)

  19. Interlayer utilization (including metal borides) for subsequent deposition of NSD films via microwave plasma CVD on 316 and 440C stainless steels

    Science.gov (United States)

    Ballinger, Jared

    Diamond thin films have promising applications in numerous fields due to the extreme properties of diamonds in conjunction with the surface enhancement of thin films. Biomedical applications are numerous including temporary implants and various dental and surgical instruments. The unique combination of properties offered by nanostructured diamond films that make it such an attractive surface coating include extreme hardness, low obtainable surface roughness, excellent thermal conductivity, and chemical inertness. Regrettably, numerous problems exist when attempting to coat stainless steel with diamond generating a readily delaminated film: outward diffusion of iron to the surface, inward diffusion of carbon limiting necessary surface carbon precursor, and the mismatch between the coefficients of thermal expansion yielding substantial residual stress. While some exotic methods have been attempted to overcome these hindrances, the most common approach is the use of an intermediate layer between the stainless steel substrate and the diamond thin film. In this research, both 316 stainless steel disks and 440C stainless steel ball bearings were tested with interlayers including discrete coatings and graded, diffusion-based surface enhancements. Titanium nitride and thermochemical diffusion boride interlayers were both examined for their effectiveness at allowing for the growth of continuous and adherent diamond films. Titanium nitride interlayers were deposited by cathodic arc vacuum deposition on 440C bearings. Lower temperature diamond processing resulted in improved surface coverage after cooling, but ultimately, both continuity and adhesion of the nanostructured diamond films were unacceptable. The ability to grow quality diamond films on TiN interlayers is in agreement with previous work on iron and low alloy steel substrates, and the similarly seen inadequate adhesion strength is partially a consequence of the lacking establishment of an interfacial carbide phase

  20. Radiative transfer in hot plasmas: a new numeric approach

    International Nuclear Information System (INIS)

    Radiative transfer is one of the main issues in inertial confinement fusion and in astrophysics. The basic equations governing the evolution of a radiative field and its coupling with a heat equation are well known, at least in the LTE approximation (Local Thermodynamic Equilibrium). However, the numerical techniques which have been developed so far are not fully satisfactory. The aim of this work has therefore been to suggest a few new ideas concerning simplicity and accuracy in the description as well as in the resolution of the equations coupling the radiative field with matter. Chapter 1 introduces the context of this work and stresses the importance of opacities in the study of the interaction between the radiation field and matter, whereas chapter 2 gives a rather complete general survey of the main physical models used until now to describe this interaction. An alternative formalism of this coupling is presented in chapter 3 where a new distribution function, based on the departure of the radiation field from thermodynamic equilibrium, is introduced. In the new resulting transport equation, the source term is now mainly determined by a time derivative and a spatial gradient of the temperature and on the other hand by a universal spectrum. This formalism includes thermal conduction in a natural way which is not the case with standard formalisms. Finally, chapter 4 presents results of the confrontation with literature data of our formalism and the numerical techniques developed, including an application to a non homogeneous medium. (author) figs., tabs., 57 refs

  1. A new approach to nanoporous graphene sheets via rapid microwave-induced plasma for energy applications

    International Nuclear Information System (INIS)

    We developed a novel approach to the fabrication of three-dimensional, nanoporous graphene sheets featuring a high specific surface area of 734.9 m2 g−1 and an ultrahigh pore volume of 4.1 cm3 g−1 through a rapid microwave-induced plasma treatment. The sheets were used as electrodes for supercapacitors and for the oxygen reduction reaction (ORR) for fuel cells. Argon-plasma grown sheets exhibited a 44% improvement of supercapacitive performance (203 F g−1) over the plasma grown sheets (141 F g−1). N-doped sheets with Co3O4 showed an outstanding ORR activity evidenced from the much smaller Tafel slope (42 mV/decade) than that of Pt/C (82 mV/decade), which is caused by the high electrical conductivity of the graphene sheets, the planar N species content and the nanoporous morphology. (paper)

  2. A consistent approach for mixed detailed and statistical calculation of opacities in hot plasmas

    CERN Document Server

    Porcherot, Quentin; Gilleron, Franck; Blenski, Thomas

    2011-01-01

    Absorption and emission spectra of plasmas with multicharged-ions contain transition arrays with a huge number of coalescent electric-dipole (E1) lines, which are well suited for treatment by the unresolved transition array and derivative methods. But, some transition arrays show detailed features whose description requires diagonalization of the Hamiltonian matrix. We developed a hybrid opacity code, called SCORCG, which combines statistical approaches with fine-structure calculations consistently. Data required for the computation of detailed transition arrays (atomic configurations and atomic radial integrals) are calculated by the super-configuration code SCO (Super-Configuration Opacity), which provides an accurate description of the plasma screening effects on the wave-functions. Level energies as well as position and strength of spectral lines are computed by an adapted RCG routine of R. D. Cowan. The resulting code provides opacities for hot plasmas and can handle mid-Z elements. The code is also a po...

  3. Imaging approaches for analysis of cholesterol distribution and dynamics in the plasma membrane.

    Science.gov (United States)

    Wüstner, Daniel; Modzel, Maciej; Lund, Frederik W; Lomholt, Michael A

    2016-09-01

    Cholesterol is an important lipid component of the plasma membrane (PM) of mammalian cells, where it is involved in control of many physiological processes, such as endocytosis, cell migration, cell signalling and surface ruffling. In an attempt to explain these functions of cholesterol, several models have been put forward about cholesterol's lateral and transbilayer organization in the PM. In this article, we review imaging techniques developed over the last two decades for assessing the distribution and dynamics of cholesterol in the PM of mammalian cells. Particular focus is on fluorescence techniques to study the lateral and inter-leaflet distribution of suitable cholesterol analogues in the PM of living cells. We describe also several methods for determining lateral cholesterol dynamics in the PM including fluorescence recovery after photobleaching (FRAP), fluorescence correlation spectroscopy (FCS), single particle tracking (SPT) and spot variation FCS coupled to stimulated emission depletion (STED) microscopy. For proper interpretation of such measurements, we provide some background in probe photophysics and diffusion phenomena occurring in cell membranes. In particular, we show the equivalence of the reaction-diffusion approach, as used in FRAP and FCS, and continuous time random walk (CTRW) models, as often invoked in SPT studies. We also discuss mass spectrometry (MS) based imaging of cholesterol in the PM of fixed cells and compare this method with fluorescence imaging of sterols. We conclude that evidence from many experimental techniques converges towards a model of a homogeneous distribution of cholesterol with largely free and unhindered diffusion in both leaflets of the PM. PMID:27016337

  4. Two approaches to plasma polarimetry: Angular variables technique and Stokes vector formalism

    Science.gov (United States)

    Bieg, Bohdan; Chrzanowski, Janusz; Kravtsov, Yury A.; Murari, Andrea; Orsitto, Francesco

    2013-08-01

    The modern plasma polarimetry is based on Stokes vector formalism (SVF) suggested and developed in depth by Segre (see Ref. [1] and cited there references). Segre's equations describe evolution of the Stokes vector along the ray in the weakly inhomogeneous and weakly anisotropic plasma. Alternative approach - angular variables technique (AVT) - suggested by Czyż et al. [2] in distinction to SVF deals with angular parameters of the polarization ellipse. Equations for angular parameters drastically differ from the SVF equations; however, AVT and SVF equations happen to be equivalent to each other. This paper proves equivalence of the SVF and AVT and in the sometime reveals some practical distinctions between two approaches. Although all the results of SVF can be obtained in frame of the AVT and vice versa, in specific problems one of the methods can be more convenient. Generally, AVT may serve as a valuable compliment to traditional SVF, providing sometimes more simple an less laborious solution of polarimetric problems.

  5. High-resolution ionospheric observations and modeling over Belgium during the solar eclipse of 20 March 2015 including first results of ionospheric tilt and plasma drift measurements

    Science.gov (United States)

    Verhulst, Tobias G. W.; Sapundjiev, Danislav; Stankov, Stanimir M.

    2016-06-01

    The ionospheric behavior over Belgium during the partial solar eclipse of 20 March 2015 is analyzed based on high-resolution solar radio flux, vertical incidence sounding, and GPS TEC measurements. First results of ionosonde-based ionospheric plasma drift and tilt observations are presented and analyzed, including some traveling ionospheric disturbances caused by the eclipse. Also, collocated ionosonde and GPS measurements are used to reconstruct the time evolution of the vertical electron density distribution using the Royal Meteorological Institute (RMI) ionospheric specification system, called Local Ionospheric Electron Density profile Reconstruction (LIEDR).

  6. Multiscale approach including microfibril scale to assess elastic constants of cortical bone based on neural network computation and homogenization method

    CERN Document Server

    Barkaoui, Abdelwahed; Tarek, Merzouki; Hambli, Ridha; Ali, Mkaddem

    2014-01-01

    The complexity and heterogeneity of bone tissue require a multiscale modelling to understand its mechanical behaviour and its remodelling mechanisms. In this paper, a novel multiscale hierarchical approach including microfibril scale based on hybrid neural network computation and homogenisation equations was developed to link nanoscopic and macroscopic scales to estimate the elastic properties of human cortical bone. The multiscale model is divided into three main phases: (i) in step 0, the elastic constants of collagen-water and mineral-water composites are calculated by averaging the upper and lower Hill bounds; (ii) in step 1, the elastic properties of the collagen microfibril are computed using a trained neural network simulation. Finite element (FE) calculation is performed at nanoscopic levels to provide a database to train an in-house neural network program; (iii) in steps 2 to 10 from fibril to continuum cortical bone tissue, homogenisation equations are used to perform the computation at the higher s...

  7. ANFIS-based approach to studying subthreshold behavior including the traps effect for nanoscale thin-film DG MOSFETs

    International Nuclear Information System (INIS)

    A fuzzy framework based on an adaptive network fuzzy inference system (ANFIS) is proposed to evaluate the relative degradation of the basic subthreshold parameters due to hot-carrier effects for nanoscale thin-film double-gate (DG) MOSFETs. The effect of the channel length and thickness on the resulting degradation is addressed, and 2-D numerical simulations are used for the elaboration of the training database. Several membership function shapes are developed, and the best one in terms of accuracy is selected. The predicted results agree well with the 2-D numerical simulations and can be efficiently used to investigate the impact of the interface fixed charges and quantum confinement on nanoscale DG MOSFET subthreshold behavior. Therefore, the proposed ANFIS-based approach offers a simple and accurate technique to study nanoscale devices, including the hot-carrier and quantum effects. (semiconductor devices)

  8. ANFIS-based approach to studying subthreshold behavior including the traps effect for nanoscale thin-film DG MOSFETs

    Institute of Scientific and Technical Information of China (English)

    T.Bentrcia; F.Djeffal; E.Chebaaki

    2013-01-01

    A fuzzy framework based on an adaptive network fuzzy inference system (ANFIS) is proposed to evaluate the relative degradation of the basic subthreshold parameters due to hot-carrier effects for nanoscale thin-film double-gate (DG) MOSFETs.The effect of the channel length and thickness on the resulting degradation is addressed,and 2-D numerical simulations are used for the elaboration of the training database.Several membership function shapes are developed,and the best one in terms of accuracy is selected.The predicted results agree well with the 2-D numerical simulations and can be efficiently used to investigate the impact of the interface fixed charges and quantum confinement on nanoscale DG MOSFET subthreshold behavior.Therefore,the proposed ANFIS-based approach offers a simple and accurate technique to study nanoscale devices,including the hot-carrier and quantum effects.

  9. New approach to the calculation of relative sensitivity factors in inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    The relative sensitivity factors (RSFs) of 68 elements including alkali, alkaline earth, rare earth, and transition elements, Cd, B, In, Te, I in the analysis by inductively coupled plasma mass spectrometry were determined. The ionization process in an inductively coupled plasma was found to be only approximately described by the Saha-Eggert equation. A relationship between the RSFs and the absolute electronegativities of atoms of the elements was found. This factor has the strongest effect on the accuracy of calculations of RSFs for chemically active elements. The average relative systematic error of calculations of RSFs with consideration for absolute electronegativity was reduced to 0.30

  10. Identification of chronic heart failure patients with a high 12-month mortality risk using biomarkers including plasma C-terminal pro-endothelin-1.

    Directory of Open Access Journals (Sweden)

    Ewa A Jankowska

    Full Text Available OBJECTIVES: We hypothesised that assessment of plasma C-terminal pro-endothelin-1 (CT-proET-1, a stable endothelin-1 precursor fragment, is of prognostic value in patients with chronic heart failure (CHF, beyond other prognosticators, including N-terminal pro-B-type natriuretic peptide (NT-proBNP. METHODS: We examined 491 patients with systolic CHF (age: 63±11 years, 91% men, New York Heart Association [NYHA] class [I/II/III/IV]: 9%/45%/38%/8%, 69% ischemic etiology. Plasma CT-proET-1 was detected using a chemiluminescence immunoassay. RESULTS: Increasing CT-proET-1 was a predictor of increased cardiovascular mortality at 12-months of follow-up (standardized hazard ratio 1.42, 95% confidence interval [CI] 1.04-1.95, p = 0.03 after adjusting for NT-proBNP, left ventricular ejection fraction (LVEF, age, creatinine, NYHA class. In receiver operating characteristic curve analysis, areas under curve for 12-month follow-up were similar for CT-proET-1 and NT-proBNP (p = 0.40. Both NT-proBNP and CT-proET-1 added prognostic value to a base model that included LVEF, age, creatinine, and NYHA class. Adding CT-proET-1 to the base model had stronger prognostic power (p<0.01 than adding NT-proBNP (p<0.01. Adding CT-proET-1 to NT-proBNP in this model yielded further prognostic information (p = 0.02. CONCLUSIONS: Plasma CT-proET-1 constitutes a novel predictor of increased 12-month cardiovascular mortality in patients with CHF. High CT-proET-1 together with high NT-proBNP enable to identify patients with CHF and particularly unfavourable outcomes.

  11. EMAPS: An Efficient Multiscale Approach to Plasma Systems with Non-MHD Scale Effects

    Energy Technology Data Exchange (ETDEWEB)

    Omelchenko, Yuri A [SciberQuest, Inc; Karimabadi, Homa [SciberQuest, Inc

    2014-10-14

    Using Discrete-Event Simulation (DES) as a novel paradigm for time integration of large-scale physics-driven systems, we have achieved significant breakthroughs in simulations of multi-dimensional magnetized plasmas where ion kinetic and finite Larmor radius (FLR) and Hall effects play a crucial role. For these purposes we apply a unique asynchronous simulation tool: a parallel, electromagnetic Particle-in-Cell (PIC) code, HYPERS (Hybrid Particle Event-Resolved Simulator), which treats plasma electrons as a charge neutralizing fluid and solves a self-consistent set of non-radiative Maxwell, electron fluid equations and ion particle equations on a structured computational grid. HYPERS enables adaptive local time steps for particles, fluid elements and electromagnetic fields. This ensures robustness (stability) and efficiency (speed) of highly dynamic and nonlinear simulations of compact plasma systems such spheromaks, FRCs, ion beams and edge plasmas. HYPERS is a unique asynchronous code that has been designed to serve as a test bed for developing multi-physics applications not only for laboratory plasma devices but generally across a number of plasma physics fields, including astrophysics, space physics and electronic devices. We have made significant improvements to the HYPERS core: (1) implemented a new asynchronous magnetic field integration scheme that preserves local divB=0 to within round-off errors; (2) Improved staggered-grid discretizations of electric and magnetic fields. These modifications have significantly enhanced the accuracy and robustness of 3D simulations. We have conducted first-ever end-to-end 3D simulations of merging spheromak plasmas. The preliminary results show: (1) tilt-driven relaxation of a freely expanding spheromak to an m=1 Taylor helix configuration and (2) possibility of formation of a tilt-stable field-reversed configuration via merging and magnetic reconnection of two double-sided spheromaks with opposite helicities.

  12. Increasing resource allocation and research into tobacco control activities: a comprehensive approach including primary prevention, treatment and brief intervention.

    Science.gov (United States)

    Richmond, R

    1993-01-01

    The range of tobacco control activities should be viewed as essential parts of a complex multi-component puzzle. Intervention strategies designed to address tobacco control should be comprehensive and include both primary and secondary prevention activities and be multi-faceted and capable of bringing about change at both the individual and broader social and cultural levels. In this paper I argue for a mutually inclusive framework in which the various components contribute in important and different ways. I examine the prevalence of smoking and identify the high risk groups, then I examine the range of available strategies and present the evidence for their success. I discuss the primary prevention approaches such as warning labels, taxes, price increases, workplace bans, education in schools, mass media and self-help materials, as well as brief interventions and treatment strategies which are conducted at the worksite, general practice and specialized cessation clinics. The areas for future research are delineated for increased resource allocation and include: the best ways to disseminate brief interventions to smokers, methods to motivate smokers; training of health professionals to deliver brief interventions; enhancing quitting and access to existing treatment resources among specific disadvantaged minority groups, e.g. migrants, unemployed youth, the effect on smoking prevalence of warning labels on cigarette packets and price rises on cigarettes. PMID:16818330

  13. Cognitive-based approach in teaching 1st year Physics for Life Sciences, including Atmospheric Physics and Climate Change components

    Science.gov (United States)

    Petelina, S. V.

    2009-12-01

    Most 1st year students who take the service course in Physics - Physics for Life Sciences - in Australia encounter numerous problems caused by such factors as no previous experience with this subject; general perception that Physics is hard and only very gifted people are able to understand it; lack of knowledge of elementary mathematics; difficulties encountered by lecturers in teaching university level Physics to a class of nearly 200 students with no prior experience, diverse and sometime disadvantageous backgrounds, different majoring areas, and different learning abilities. As a result, many students either drop, or fail the subject. In addition, many of those who pass develop a huge dislike towards Physics, consider the whole experience as time wasted, and spread this opinion among their peers and friends. The above issues were addressed by introducing numerous changes to the curriculum and modifying strategies and approaches in teaching Physics for Life Sciences. Instead of a conventional approach - teaching Physics from simple to complicated, topic after topic, the students were placed in the world of Physics in the same way as a newborn child is introduced to this world - everything is seen all the time and everywhere. That created a unique environment where a bigger picture and all details were always present and interrelated. Numerous concepts of classical and modern physics were discussed, compared, and interconnected all the time with “Light” being a key component. Our primary field of research is Atmospheric Physics, in particular studying the atmospheric composition and structure using various satellite and ground-based data. With this expertise and also inspired by an increasing importance of training a scientifically educated generation who understands the challenges of the modern society and responsibilities that come with wealth, a new section on environmental physics has been developed. It included atmospheric processes and the greenhouse

  14. An LC-MS/MS method to quantify acylcarnitine species including isomeric and odd-numbered forms in plasma and tissues.

    Science.gov (United States)

    Giesbertz, Pieter; Ecker, Josef; Haag, Alexander; Spanier, Britta; Daniel, Hannelore

    2015-10-01

    Acylcarnitines are intermediates of fatty acid and amino acid oxidation found in tissues and body fluids. They are important diagnostic markers for inherited diseases of peroxisomal and mitochondrial oxidation processes and were recently described as biomarkers of complex diseases like the metabolic syndrome. Quantification of acylcarnitine species can become challenging because various species occur as isomers and/or have very low concentrations. Here we describe a new LC-MS/MS method for quantification of 56 acylcarnitine species with acyl-chain lengths from C2 to C18. Our method includes amino acid-derived positional isomers, like methacrylyl-carnitine (2-M-C3:1-CN) and crotonyl-carnitine (C4:1-CN), and odd-numbered carbon species, like pentadecanoyl-carnitine (C15:0-CN) and heptadecanoyl-carnitine (C17:0-CN), occurring at very low concentrations in plasma and tissues. Method validation in plasma and liver samples showed high sensitivity and excellent accuracy and precision. In an application to samples from streptozotocin-treated diabetic mice, we identified significantly increased concentrations of acylcarnitines derived from branched-chain amino acid degradation and of odd-numbered straight-chain species, recently proposed as potential biomarkers for the metabolic syndrome. In conclusion, the LC-MS/MS method presented here allows robust quantification of isomeric acylcarnitine species and extends the palette of acylcarnitines with diagnostic potential derived from fatty acid and amino acid metabolism. PMID:26239049

  15. Thermodynamic coherence of the Variational Average-Atom in Quantum Plasmas (VAAQP) approach

    CERN Document Server

    Piron, R; Cichocki, B

    2009-01-01

    A new code called VAAQP (Variational Average-Atom in Quantum Plasmas) is reported. The model as well as main results of previous studies are briefly recalled. The code is based on a new fully variational model of dense plasmas at equilibrium with quantum treatment of all electrons. The code can calculate the Average Atom structure and the mean ionization from the variational equations respecting the virial theorem and without imposing the neutrality of the Wigner-Seitz sphere. The formula obtained for the electronic pressure is simple and does not require any numerical differentiation. A description of the principal features of the code is given. The thermodynamic consistency of the results obtained with VAAQP is shown by a comparison with another approach on the example of the aluminium 10 eV isotherm EOS curve. A first comparison to an INFERNO-type model is also presented.

  16. Study of a pseudo-empirical model approach to characterize plasma actuators

    Energy Technology Data Exchange (ETDEWEB)

    Marziali Bermudez, M [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, UBA, Ciudad Universitaria Pab. I, Buenos Aires 1428 (Argentina); Sosa, R; Artana, G [Laboratorio de Fluidodinamica, Facultad de Ingenieria, UBA, Av. Paseo Colon 850, Buenos Aires 1063 (Argentina); Grondona, D; Marquez, A; Kelly, H, E-mail: rsosa@fi.uba.ar [Instituto de Fisica del Plasma (CONICET) - Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, UBA, Ciudad Universitaria Pab. I, Buenos Aires 1428 (Argentina)

    2011-05-01

    The use of plasma actuators is a recent technology that imposes a localized electric force that is used to control air flows. A suitable representation of actuation enables to undertake plasma actuators optimization, to design flow-control strategies, or to analyse the flow stabilization that can be attained by plasma forcing. The problem description may be clearly separated in two regions. An outer region, where the fluid is electrically neutral, in which the flow is described by the Navier-Stokes equation without any forcing term. An inner region, that forms a thin boundary layer, where the fluid is ionized and electric forces are predominant. The outer limit of the inner solution becomes the boundary condition for the outer problem. The outer problem can then be solved with a slip velocity that is issued from the inner solution. Although the solution for the inner problem is quite complex it can be contoured proposing pseudo-empirical models where the slip velocity of the outer problem is determined indirectly from experiments. This pseudo-empirical model approach has been recently tested in different cylinder flows and revealed quite adapted to describe actuated flow behaviour. In this work we determine experimentally the influence of the duty cycle on the slip velocity distribution. The velocity was measured by means of a pitot tube and flow visualizations of the starting vortex (i.e. the induced flow when actuation is activated in a quiescent air) have been done by means of the Schlieren technique. We also performed numerical experiments to simulate the outer region problem when actuation is activated in a quiescent air using a slip velocity distribution as a boundary condition. The experimental and numerical results are in good agreement showing the potential of this pseudo-empirical model approach to characterize the plasma actuation.

  17. Radio and Plasma Wave Observations at Saturn from Cassini's Approach and First Orbit

    Science.gov (United States)

    Gurnett, D. A.; Kurth, W. S.; Haspodarsky, G. B.; Persoon, A. M.; Averkamp, T. F.; Cecconi, B.; Lecacheux, A.; Zarka, P.; Canu, P.; Cornilleau-Wehrlin, N.

    2005-01-01

    We report data from the Cassini radio and plasma wave instrument during the approach and first orbit at Saturn. During the approach, radio emissions from Saturn showed that the radio rotation period is now 10 hours 45 minutes 45 k 36 seconds, about 6 minutes longer than measured by Voyager in 1980 to 1981. In addition, many intense impulsive radio signals were detected from Saturn lightning during the approach and first orbit. Some of these have been linked to storm systems observed by the Cassini imaging instrument. Within the magnetosphere, whistler-mode auroral hiss emissions were observed near the rings, suggesting that a strong electrodynamic interaction is occurring in or near the rings.

  18. Integrated Approach to Dense Magnetized Plasmas Applications in Nuclear Fusion Technology. Report of a Coordinated Research Project 2007-2011

    International Nuclear Information System (INIS)

    Through its coordinated research activities, the IAEA promotes the development and application of nuclear technologies in Member States. The scientific and technical knowledge required for the construction and operation of large nuclear fusion research facilities, including ITER and the Laser Megajoule in France, and the Z machine and the National Ignition Facility in the United States of America, necessitates several accompanying research and development programmes in physics and technology. This is particularly true in the areas of materials science and fusion technology. Hence, the long standing IAEA effort to conduct coordinated research projects (CRPs) in these areas is aimed at: (i) the development of appropriate technical tools to investigate the issue of materials damage and degradation in a fusion plasma environment; and (ii) the emergence of a knowledge based understanding of the various processes underlying materials damage and degradation, thereby leading to the identification of suitable candidate materials fulfilling the stringent requirements of a fusion environment in any next step facility. Dense magnetized plasma (DMP) devices serve as a first test bench for testing of fusion relevant plasma facing materials, diagnostic development and calibration, technologies and scaling to conceptual principles of larger devices while sophisticated testing facilities such as the International Fusion Materials Irradiation Facility (IFMIF) are being designed. The CRP on Integrated Approach to Dense Magnetized Plasmas Applications in Nuclear Fusion Technology described herein was initiated in 2007 with the participation of 12 research institutions in 8 Member States and was concluded in 2011. It was designed with specific research objectives falling into two main categories: support to mainstream fusion research and development of DMP technology. This publication is a compilation of the individual reports submitted by the 12 CRP participants. These reports discuss

  19. Radiative opacity of plasmas studied by detailed term (level) accounting approaches

    Institute of Scientific and Technical Information of China (English)

    ZENG Jiao-long; JIN Feng-tao; YUAN Jian-min

    2006-01-01

    Detailed term and level accounting (DTA and DLA) schemes have been developed to calculate the spectrally resolved and Rosseland and Planck mean opacities of plasmas in local thermodynamic equilibrium.Various physical effects,such as configuration interaction effect (including core-valence electron correlations effect and relativistic effect),detailed line width effect (including the line saturation effect),etc.,on the opacity of plasmas have been investigated in detail.Some of these physical effects are less capable or even impossible to be taken into account by statistical models such as unresolved transition arrays,super-transitionarray or average atom models.Our detailed model can obtain accurate opacity of plasmas.Using this model,we have systematically investigated the radiative opacities of low,medium and high-Z plasmas under different conditions of temperature and density.For example,for aluminum plasma,in the X-ray region,we demonstrated the effects of autoionization resonance broadening on the opacity for the first time.Furthermore,the relativistic effects play an important role on the opacity as well.Our results are in good agreement with other theoretical ones although better agreement can be obtained after the effects of autoionization resonance broadening and relativity have been considered.Our results also show that the modelling of the opacity is very complicated,since too many physical effects influence the accuracy of opacity.``For medium and high-Z plasmas,however,there are systematic discrepancies unexplained so far between the theoretical and experimental opacities.Here,the theoretical opacities are mainly obtained by statistical models.To clarify the discrepaneies,efforts from both sides are needed.From the viewpoint of theory,however,a DLA method,in which various physical effects can be taken into account,should be useful in resolving the difference.Taking gold plasma as an example,we studied in detail the effects of core-valence electron

  20. GLOBAL APPROACH OF CHANNEL MODELING IN MOBILE AD HOC NETWORKS INCLUDING SECOND ORDER STATISTICS AND SYSTEM PERFORMANCES ANALYSIS

    Directory of Open Access Journals (Sweden)

    Basile L. AGBA

    2008-06-01

    Full Text Available Mobile ad hoc networks (MANET are very difficult to design in terms of scenarios specification and propagation modeling. All these aspects must be taken into account when designing MANET. For cost-effective designing, powerful and accurate simulation tools are needed. Our first contribution in this paper is to provide a global approach process (GAP in channel modeling combining scenarios and propagation in order to have a better analysis of the physical layer, and finally to improve performances of the whole network. The GAP is implemented in an integrated simulation tool, Ad-SMPro. Moreover, channel statistics, throughput and delay are some key points to be considered when studying a mobile wireless networks. A carefully analysis of mobility effects over second order channel statistics and system performances is made based on our optimized simulation tool, Ad-SMProl. The channel is modeled by large scale fading and small scale fading including Doppler spectrum due to the double mobility of the nodes. Level Cross Rate and Average Duration of Fade are simulated as function of double mobility degree, a defined to be the ratio of the nodes' speeds. These results are compared to the theoretical predictions. We demonstrate that, in mobile ad hoc networks, flat fading channels and frequency-selective fading channels are differently affected. In addition, Bit Error rate is analysed as function of the ratio of the average bit energy to thermal noise density. Other performances (such as throughput, delay and routing traffic are analysed and conclusions related to the proposed simulation model and the mobility effects are drawn.

  1. Multiscale approach including microfibril scale to assess elastic constants of cortical bone based on neural network computation and homogenization method.

    Science.gov (United States)

    Barkaoui, Abdelwahed; Chamekh, Abdessalem; Merzouki, Tarek; Hambli, Ridha; Mkaddem, Ali

    2014-03-01

    The complexity and heterogeneity of bone tissue require a multiscale modeling to understand its mechanical behavior and its remodeling mechanisms. In this paper, a novel multiscale hierarchical approach including microfibril scale based on hybrid neural network (NN) computation and homogenization equations was developed to link nanoscopic and macroscopic scales to estimate the elastic properties of human cortical bone. The multiscale model is divided into three main phases: (i) in step 0, the elastic constants of collagen-water and mineral-water composites are calculated by averaging the upper and lower Hill bounds; (ii) in step 1, the elastic properties of the collagen microfibril are computed using a trained NN simulation. Finite element calculation is performed at nanoscopic levels to provide a database to train an in-house NN program; and (iii) in steps 2-10 from fibril to continuum cortical bone tissue, homogenization equations are used to perform the computation at the higher scales. The NN outputs (elastic properties of the microfibril) are used as inputs for the homogenization computation to determine the properties of mineralized collagen fibril. The mechanical and geometrical properties of bone constituents (mineral, collagen, and cross-links) as well as the porosity were taken in consideration. This paper aims to predict analytically the effective elastic constants of cortical bone by modeling its elastic response at these different scales, ranging from the nanostructural to mesostructural levels. Our findings of the lowest scale's output were well integrated with the other higher levels and serve as inputs for the next higher scale modeling. Good agreement was obtained between our predicted results and literature data. PMID:24123969

  2. Thermalization of a boost-invariant non-Abelian plasma: Holographic approach with boundary sourcing

    CERN Document Server

    Bellantuono, Loredana; De Fazio, Fulvia; Giannuzzi, Floriana

    2015-01-01

    In a holographic approach, the evolution of a 4D strongly coupled non-Abelian plasma towards equilibrium can be studied investigating a 5D gravitational dual. The process driving the plasma out-of-equilibrium can be described by boundary sourcing, a deformation of the boundary metric; the analysis of the late-time dynamics allows to understand how the hydrodynamic regime settles in. We apply the method to a boost-invariant case, considering the effects of different quenches, solving the Einstein equations in the bulk and studying the time-dependence of observables such as the effective temperature, the energy density and the pressures. The main outcome is that, if the effective temperature of the system when the quench is switched off is $T_{eff}(\\tau^*)=500$ MeV, thermalization is reached within a time of ${\\cal O}$(1 fm/c), an important information if the case of the QCD plasma produced in relativistic heavy ion collisions is considered.

  3. A Novel Targeted Approach for Noninvasive Detection of Paternally Inherited Mutations in Maternal Plasma.

    Science.gov (United States)

    van den Oever, Jessica M E; van Minderhout, Ivonne J H M; Harteveld, Cornelis L; den Hollander, Nicolette S; Bakker, Egbert; van der Stoep, Nienke; Boon, Elles M J

    2015-09-01

    The challenge in noninvasive prenatal diagnosis for monogenic disorders lies in the detection of low levels of fetal variants in the excess of maternal cell-free plasma DNA. Next-generation sequencing, which is the main method used for noninvasive prenatal testing and diagnosis, can overcome this challenge. However, this method may not be accessible to all genetic laboratories. Moreover, shotgun next-generation sequencing as, for instance, currently applied for noninvasive fetal trisomy screening may not be suitable for the detection of inherited mutations. We have developed a sensitive, mutation-specific, and fast alternative for next-generation sequencing-mediated noninvasive prenatal diagnosis using a PCR-based method. For this proof-of-principle study, noninvasive fetal paternally inherited mutation detection was performed using cell-free DNA from maternal plasma. Preferential amplification of the paternally inherited allele was accomplished through a personalized approach using a blocking probe against maternal sequences in a high-resolution melting curve analysis-based assay. Enhanced detection of the fetal paternally inherited mutation was obtained for both an autosomal dominant and a recessive monogenic disorder by blocking the amplification of maternal sequences in maternal plasma. PMID:26162331

  4. Challenges and solutions in the bioanalysis of BMS-986094 and its metabolites including a highly polar, active nucleoside triphosphate in plasma and tissues using LC-MS/MS.

    Science.gov (United States)

    Liu, Ang; Lute, John; Gu, Huidong; Wang, Bonnie; Trouba, Kevin J; Arnold, Mark E; Aubry, Anne-Françoise; Wang, Jian

    2015-09-01

    BMS-986094, a nucleotide polymerase inhibitor of the hepatitis C virus, was withdrawn from clinical trials because of a serious safety issue. To investigate a potential association between drug/metabolite exposure and toxicity in evaluations conducted after the termination of the BMS-986094 development program, it was essential to determine the levels of BMS-986094 and its major metabolites INX-08032, INX-08144 and INX-09054 in circulation and the active nucleoside triphosphate INX-09114 in target and non-target tissues. However, there were many challenges in the bioanalysis of these compounds. The chromatography challenge for the extremely polar nucleoside triphosphate was solved by applying mixed-mode chromatography which combined anion exchange and reversed-phase interactions. The LC conditions provided adequate retention and good peak shape of the analyte and showed good robustness. A strategy using simultaneous extraction but separate LC analysis of the prodrug BMS-986094 and its major circulating metabolites was used to overcome a carryover issue of the hydrophobic prodrug while still achieving good chromatography of the polar metabolites. In addition, the nucleotide analytes were not stable in the presence of endogenous enzymes. Low pH and low temperature were required for blood collection and plasma sample processing. However, the use of phosphatase inhibitor and immediate homogenization and extraction were critical for the quantitative analysis of the active triphosphate, INX-09114, in tissue samples. To alleviate the bioanalytical complexity caused by multiple analytes, different matrices, and various species, a fit-for-purpose approach to assay validation was implemented based on the needs of drug safety assessment in non-clinical (GLP or non-GLP) studies. The assay for INX-08032 was fully validated in plasma of toxicology species. The lower limit of quantification was 1.00ng/mL and the linear curve range was 1.00-500.00ng/mL using a weighted (1/x(2

  5. New Statistical Multiparticle Approach to the Acceleration of Electrons by the Ion Field in Plasmas

    Directory of Open Access Journals (Sweden)

    Eugene Oks

    2010-01-01

    Full Text Available The phenomenon of the acceleration of the (perturbing electrons by the ion field (AEIF significantly reduces Stark widths and shifts in plasmas of relatively high densities and/or relatively low temperature. Our previous analytical calculations of the AEIF were based on the dynamical treatment: the starting point was the ion-microfield-caused changes of the trajectories and velocities of individual perturbing electrons. In the current paper, we employ a statistical approach: the starting point is the electron velocity distribution function modified by the ion microfield. The latter had been calculated by Romanovsky and Ebeling in the multiparticle description of the ion microfield. The result shows again the reduction of the electron Stark broadening. Thus two totally different analytical approaches (dynamical and statistical agree with each other and therefore disprove the corresponding recent fully-numerical simulations by Stambulchik et al. that claimed an increase of the electron Stark broadening.

  6. The field line map approach for simulations of magnetically confined plasmas

    Science.gov (United States)

    Stegmeir, Andreas; Coster, David; Maj, Omar; Hallatschek, Klaus; Lackner, Karl

    2016-01-01

    Predictions of plasma parameters in the edge and scrape-off layer of tokamaks is difficult since most modern tokamaks have a divertor and the associated separatrix causes the usually employed field/flux-aligned coordinates to become singular on the separatrix/X-point. The presented field line map approach avoids such problems as it is based on a cylindrical grid: standard finite-difference methods can be used for the discretisation of perpendicular (w.r.t. magnetic field) operators, and the characteristic flute mode property (k∥ ≪k⊥) of structures is exploited computationally via a field line following discretisation of parallel operators which leads to grid sparsification in the toroidal direction. This paper is devoted to the discretisation of the parallel diffusion operator (the approach taken is very similar to the flux-coordinate independent (FCI) approach which has already been adopted to a hyperbolic problem (Ottaviani, 2011; Hariri, 2013)). Based on the support operator method, schemes are derived which maintain the self-adjointness property of the parallel diffusion operator on the discrete level. These methods have very low numerical perpendicular diffusion compared to a naive discretisation which is a critical issue since magnetically confined plasmas exhibit a very strong anisotropy. Two different versions of the discrete parallel diffusion operator are derived: the first is based on interpolation where the order of interpolation and therefore the numerical diffusion is adjustable; the second is based on integration and is advantageous in cases where the field line map is strongly distorted. The schemes are implemented in the new code GRILLIX, and extensive benchmarks and numerous examples are presented which show the validity of the approach in general and GRILLIX in particular.

  7. Two approaches to plasma polarimetry: Angular variables technique and Stokes vector formalism

    Energy Technology Data Exchange (ETDEWEB)

    Bieg, Bohdan, E-mail: b.bieg@am.szczecin.pl [Maritime University of Szczecin, Szczecin (Poland); Chrzanowski, Janusz; Kravtsov, Yury A. [Maritime University of Szczecin, Szczecin (Poland); Murari, Andrea [Associazione EURATOM-ENEA, Padova (Italy); Orsitto, Francesco [Associazione EURATOM-ENEA, Frascati (Italy)

    2013-08-21

    The modern plasma polarimetry is based on Stokes vector formalism (SVF) suggested and developed in depth by Segre (see Ref. [1] and cited there references). Segre's equations describe evolution of the Stokes vector along the ray in the weakly inhomogeneous and weakly anisotropic plasma. Alternative approach – angular variables technique (AVT) – suggested by Czyż et al. [2] in distinction to SVF deals with angular parameters of the polarization ellipse. Equations for angular parameters drastically differ from the SVF equations; however, AVT and SVF equations happen to be equivalent to each other. This paper proves equivalence of the SVF and AVT and in the sometime reveals some practical distinctions between two approaches. Although all the results of SVF can be obtained in frame of the AVT and vice versa, in specific problems one of the methods can be more convenient. Generally, AVT may serve as a valuable compliment to traditional SVF, providing sometimes more simple an less laborious solution of polarimetric problems.

  8. The Kalman filter approach to inductively coupled plasma atomic emission spectrometry

    Science.gov (United States)

    Van Veen, E. H.; Bosch, S.; De Loos-Vollebregt, M. T. C.

    1994-07-01

    This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hardcopy text, comprising the main article and two appendices, is accompanied by a disk containing the compiled program, a reference manual and data files. The work deals with data handling in inductively coupled plasma atomic emission spectrometry (ICP-AES). With this technique, the analyte signal is superimposed on a background signal. When separating the signals by manual or automated three-point background correction, there are many instances in which the data reduction fails. Based on scans recorded in a fast-scanning mode and on a library of pure-component scans, the Kaiman filter approach models the emission in the spectral window (about 100 pm) of the analyte and mathematically solves the problem of background correction. By using a criterion-based algorithm to correct for optical instability, the uncertainty in the determination of the interferent line signal is eliminated. Therefore, the present filter implementation yields more accurate and precise results, especially in the case of line overlap. The Kalman filter Approach to Atomic Spectrometry (KAAS) software automatically processes Perkin-Elmer Plasma 1000/2000 text files, but can also handle ASCII data files. Practical and comprehensive examples are given to evoke the "Kalman filter feeling" in the crucial step of creating the emission model.

  9. Clear detection of ADIPOQ locus as the major gene for plasma adiponectin: Results of genome-wide association analyses including 4659 European individuals

    NARCIS (Netherlands)

    I.M. Heid (Iris); P. Henneman (Peter); A.A. Hicks (Andrew); S. Coassin (Stefan); T.W. Winkler (Thomas); Y.S. Aulchenko (Yurii); C. Fuchsberger (Christian); K. Song (Kijoung); M.F. Hivert; D. Waterworth (Dawn); N. Timpson (Nicholas); J.B. Richards (Brent); J.R.B. Perry (John); T. Tanaka (Toshiko); N. Amin (Najaf); B. Kollerits (Barbara); I. Pichler (Irene); B.A. Oostra (Ben); B. Thorand (Barbara); R.R. Frants (Rune); T. Illig (Thomas); J. Dupuis (Josée); B. Glaser (Beate); T.D. Spector (Timothy); J.M. Guralnik (Jack); J.M. Egan (Josephine); J.C. Florez (Jose); D.M. Evans (David); N. Soranzo (Nicole); S. Bandinelli (Stefania); O.D. Carlson (Olga); T.M. Frayling (Timothy); K.A. Burling (Keith); G.D. Smith; V. Mooser (Vincent); L. Ferrucci (Luigi); J.B. Meigs (James); P. Vollenweider (Peter); K.W.v. Dijk; P.P. Pramstaller (Peter Paul); F. Kronenberg (Florian); P. Tikka-Kleemola (Päivi)

    2010-01-01

    textabstractObjective: Plasma adiponectin is strongly associated with various components of metabolic syndrome, type 2 diabetes and cardiovascular outcomes. Concentrations are highly heritable and differ between men and women. We therefore aimed to investigate the genetics of plasma adiponectin in m

  10. The odyssey of Hsp60 from tumor cells to other destinations includes plasma membrane-associated stages and Golgi and exosomal protein-trafficking modalities.

    Directory of Open Access Journals (Sweden)

    Claudia Campanella

    Full Text Available BACKGROUND: In a previous work we showed for the first time that human tumor cells secrete Hsp60 via exosomes, which are considered immunologically active microvesicles involved in tumor progression. This finding raised questions concerning the route followed by Hsp60 to reach the exosomes, its location in them, and whether Hsp60 can be secreted also via other mechanisms, e.g., by the Golgi. We addressed these issues in the work presented here. PRINCIPAL FINDINGS: We found that Hsp60 localizes in the tumor cell plasma membrane, is associated with lipid rafts, and ends up in the exosomal membrane. We also found evidence that Hsp60 localizes in the Golgi apparatus and its secretion is prevented by an inhibitor of this organelle. CONCLUSIONS/SIGNIFICANCE: We propose a multistage process for the translocation of Hsp60 from the inside to the outside of the cell that includes a combination of protein traffic pathways and, ultimately, presence of the chaperonin in the circulating blood. The new information presented should help in designing future strategies for research and for developing diagnostic-monitoring means useful in clinical oncology.

  11. Calculation of Internal Energy and Pressure of Dense hydrogen Plasma by Direct Path Integral Monte Carlo Approach

    Institute of Scientific and Technical Information of China (English)

    刘松芬; 胡北来

    2003-01-01

    The internal energy and pressure of dense hydrogen plasma are calculated by the direct path integral Monte Carlo approach. The Kelbg potential is used as interaction potentials both between electrons and between protons and electrons in the calculation. The complete formulae for internal energy and pressure in dense hydrogen plasma derived for the simulation are presented. The correctness of the derived formulae are validated by the obtained simulation results. The numerical results are discussed in details.

  12. Three-Dimensional Simulation of Plasma Deformation During Contact Opening in a Circuit Breaker, Including the Analysis of Kink Instability and Sausage Instability

    Institute of Scientific and Technical Information of China (English)

    Vahid ABBASI; Ahmad GHOLAMI; Kaveh NIAYESH

    2012-01-01

    A three-dimensional (3-D) transient model has been developed to investigate plasma deformation driven by a magnetic field and its influence on arc stability in a circuit breaker. The 3-D distribution of electric current density is obtained from a current continuity equation along with the generalized Ohm's law; while the magnetic field induced by the current flowing through the arc column is calculated by the magnetic vector potential equation. When gas interacts with an arc column, fundamental factors, such as Ampere's law, Ohm's law, the turbulence model, transport equations of mass, momentum and energy of plasma flow, have to be coupled for aria- lyzing the phenomenon. The coupled interactions between arc and plasma flow are described in the fl'amework of time-dependent magnetohydrodynamic (MHD) equations in conjunction with a K-~ turbulence model. Simulations have been focused on sausage and kink instabilities in plasma (these phenomena are related tO pinch effects and electromagnetic fields). The 3-D sjm- ulation reveals the relation between plasma deformation and instability phenomena, which affect arc stability during circuit breaker operation. Plasma deformation is the consequence of coupled interactions between the electromagnetic force and plasma flow described in simulations.

  13. Approach to Chandrasekhar-Kendall-Woltjer State in a Chiral Plasma

    CERN Document Server

    Xia, Xiao-liang; Wang, Qun

    2016-01-01

    We study the time evolution of the magnetic field in a plasma with a chiral magnetic current. The Vector Spherical Harmonic functions (VSH) are used to expand all fields. We define a measure for the Chandrasekhar-Kendall-Woltjer (CKW) state, which has a simple form in VSH expansion. We propose the conditions for a general class of initial momentum spectra that will evolve into the CKW state. For this class of initial conditions, to approach the CKW state, (i) a non-vanishing chiral magnetic conductivity is necessary, and (ii) the time integration of the product of the electric resistivity and chiral magnetic conductivity must grow faster than the time integration of the resistivity. We give a few examples to test these conditions numerically which work very well.

  14. An Asset Pricing Approach to Testing General Term Structure Models including Heath-Jarrow-Morton Specifications and Affine Subclasses

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; van der Wel, Michel

    is tested, but in addition to the standard bilinear term in factor loadings and market prices of risk, the relevant mean restriction in the term structure case involves an additional nonlinear (quadratic) term in factor loadings. We estimate our general model using likelihood-based dynamic factor model...... techniques for a variety of volatility factors, and implement the relevant likelihood ratio tests. Our factor model estimates are similar across a general state space implementation and an alternative robust two-step principal components approach. The evidence favors time-varying market prices of risk. Most...... of the risk premium is associated with the slope factor, and individual risk prices depend on own past values, factor realizations, and past values of other risk prices, and are significantly related to the output gap, consumption, and the equity risk price. The absence of arbitrage opportunities is strongly...

  15. An Approach for Including Uncertainty in Integrated Water Resources Assessments within Large River Basins of Southern Africa.

    Science.gov (United States)

    Hughes, D.

    2015-12-01

    There are many large basins in southern Africa that are mostly ungauged but may have some streamflow observations either on the main river or on tributaries. Many of the streamflow records are, however, of poor quality or impacted by largely unquantified and non-stationary development impacts. All water resources assessments are therefore uncertain and model setups are difficult to validate in traditional ways. The paper presents a method for practical uncertainty assessment using a semi-distributed (sub-basin) model. The method uses a 2-stage approach where the first stage involves obtaining 'behavioural' parameter sets to represent the incremental natural streamflow for each sub-basin. The criteria for 'behavioural' are based on a series of constraints on model output that can be developed from the available gauged data or from regional assessments of natural hydrological functioning. The second stage simulates the whole basin based on sampling the 'behavioural' incremental flow parameter sets, as well as samples of additional individual parameter values representing downstream routing parts of the model and development impacts. One of the perceived advantage of the method is that all the ensembles at the total basin outlet are made up of behavioural inputs for all sub-basins. The method is also flexible in terms of the uncertainty range of the constraints, which might be expected to be narrow (low uncertainty) in well gauged sub-basins, or areas where our understanding of flow regime characteristics is good, but much wider (higher uncertainty) in other parts of the basin. The paper briefly explains the approach and discusses some of the issues associated with its application using examples from southern Africa.

  16. Exploration of Plasma Jets Approach to High Energy Density Physics. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chiping [Massachusetts Institute of Technology

    2013-08-26

    High-energy-density laboratory plasma (HEDLP) physics is an emerging, important area of research in plasma physics, nuclear physics, astrophysics, and particle acceleration. While the HEDLP regime occurs at extreme conditions which are often found naturally in space but not on the earth, it may be accessible by colliding high intensity plasmas such as high-energy-density plasma jets, plasmoids or compact toroids from plasma guns. The physics of plasma jets is investigated in the context of high energy density laboratory plasma research. This report summarizes results of theoretical and computational investigation of a plasma jet undergoing adiabatic compression and adiabatic expansion. A root-mean-squared (rms) envelope theory of plasma jets is developed. Comparison between theory and experiment is made. Good agreement between theory and experiment is found.

  17. The CELLULOSE-SYNTHASE LIKE C (CSLC) Family of Barley Includes Members that Are Integral Membrane Proteins Targeted to the Plasma Membrane

    Institute of Scientific and Technical Information of China (English)

    Fenny M. Dwivany; Dina Yuli; Rachel A. Burton; Neil J. Shirley; Sarah M. Wilson; Geoffrey B. Fincher; Antony Bacic; Ed Newbigin; Monika S. Doblin

    2009-01-01

    The CELLULOSESYNTHASE-LIKE C(CSLC) family is an ancient lineage within the CELLULOSE SYNTHASE/CEL-LULOSE SYNTHASE-LIKE (CESA/CSL) polysaccharide synthase superfamily that is thought to have arisen before the diver-gence of mosses and vascular plants. As studies in the flowering plant Arabidopsis have suggested synthesis of the (1,4)-β-glucan backbone of xyloglucan (XyG), a wall polysaccharide that tethers adjacent cellulose microfibrils to each other, as a probable function for the CSLCs, CSLC function was investigated in barley (Hordeum vulgare L.), a species with low amounts of XyG in its walls. Four barley CSLC genes were identified (designated HvCSLC1-4). Phylogenetic analysis reveals three well supported clades of CSLCs in flowering plants, with barley having representatives in two of these clades. The four barley CSLCs were expressed in various tissues, with in situ PCR detecting transcripts in all cell types of the coleoptile and root, including cells with primary and secondary cell walls. Co-expression analysis showed that HvCSLC3 was coor-dinately expressed with putative XyG xylosyltransferase genes. Both immuno-EM and membrane fractionation showed that HvCSLC2 was located in the plasma membrane of barley suspension-cultured cells and was not in internal membranes such as endoplasmic reticulum or Golgi apparatus. Based on our current knowledge of the sub-cellular locations of poly-saccharide synthesis, we conclude that the CSLC family probably contains more than one type of polysaccharide synthase.

  18. Unified model to the Tungsten inert Gas welding process including the cathode, the plasma and the anode; Modele couple cathode-plasma-piece en vue de la simulation du procede de soudage a l'arc TIG

    Energy Technology Data Exchange (ETDEWEB)

    Brochard, M.

    2009-06-15

    During this work, a 2D axially symmetric model of a TIG arc welding process had been developed in order to predict for given welding parameters, the needed variables for a designer of welded assembly: the heat input on the work piece, the weld pool geometry,... The developed model, using the Cast3M finite elements software, deals with the physical phenomena acting in each part of the process: the cathode, the plasma, the work piece with a weld pool, and the interfaces between these parts. To solve this model, the thermohydraulics equations are coupled with the electromagnetic equations that are calculated in part using the least squares finite element method. The beginning of the model validation consisted in comparing the results obtained with the ones available in the scientific literature. Thus, this step points out the action of each force in the weld pool, the contribution of each heat flux in the energy balance. Finally, to validate the model predictiveness, experimental and numerical sensitivity analyses were conducted using a design of experiments approach. The effects of the process current, the arc gap and the electrode tip angle on the weld pool geometry and the energy transferred to the work piece and the arc efficiency were studied. The good agreement obtained by the developed model for these outputs shows the good reproduction of the process physics. (author)

  19. Modelling the turbulent transport of angular momentum in tokamak plasmas - A quasi-linear gyrokinetic approach

    International Nuclear Information System (INIS)

    The magnetic confinement in tokamaks is for now the most advanced way towards energy production by nuclear fusion. Both theoretical and experimental studies showed that rotation generation can increase its performance by reducing the turbulent transport in tokamak plasmas. The rotation influence on the heat and particle fluxes is studied along with the angular momentum transport with the quasi-linear gyro-kinetic eigenvalue code QuaLiKiz. For this purpose, the QuaLiKiz code is modified in order to take the plasma rotation into account and compute the angular momentum flux. It is shown that QuaLiKiz framework is able to correctly predict the angular momentum flux including the E*B shear induced residual stress as well as the influence of rotation on the heat and particle fluxes. The major approximations of QuaLiKiz formalisms are reviewed, in particular the ballooning representation at its lowest order and the eigenfunctions calculated in the hydrodynamic limit. The construction of the quasi-linear fluxes is also reviewed in details and the quasi-linear angular momentum flux is derived. The different contributions to the turbulent momentum flux are studied and successfully compared both against non-linear gyro-kinetic simulations and experimental data. (author)

  20. Rayleigh-Taylor instability in partially ionized compressible plasmas: one fluid approach

    CERN Document Server

    Diaz, A J; Collados, M

    2014-01-01

    We study the modification of the classical criterion for the linear onset and growth rate of the Rayleigh-Taylor instability (RTI) in a partially ionized (PI) plasma in the one-fluid description, considering a generalized induction equation. The governing linear equations and appropriate boundary conditions, including gravitational terms, are derived and applied to the case of the RTI in a single interface between two partially ionized plasmas. The boundary conditions lead to an equation for the frequencies in which some of them have positive complex parts, marking the appearance of the RTI. We study the ambipolar term alone first, extending the result to the full induction equation later. We find that the configuration is always unstable because of the presence of a neutral species. In the classical stability regime the growth rate is small, since the collisions prevent the neutral fluid to fully develop the RTI. For parameters in the classical instability regime the growth rate is lowered, but for the consi...

  1. A comparison of paraxial and extended paraxial approach for laser beam propagation in plasma

    International Nuclear Information System (INIS)

    The propagation of laser beam in the plasma has been investigated for two cases, first with imposing the restriction of paraxial approximation on the beam profile, and second relaxing the restriction on the profile up to a certain extent. Besides the standard ponderomotive nonlinearity the work also includes the nonlinearity that arises from the relativistic electron velocities. The expression for the laser beam width parameter has been derived by expanding the eikonal, dielectric constant and other relevant quantities up to the fourth power of r, therefore, the contribution of both r2 and r4 terms is incorporated in the present analysis. The dynamical equation governing the beam width parameter has been numerically solved for typical laser plasma parameters. The result shows that the focusing of the laser beams has been affected and becomes fast due to the contribution of the off-axial rays in the extended-paraxial region. The intensity of the laser beam has also been examined in the light of these two cases and a notable change is found in the magnitude in the laser beam intensity with modified-paraxial case as compared to the paraxial case.

  2. Clinical Immunology Review Series: an approach to the patient with recurrent orogenital ulceration, including Behçet's syndrome.

    LENUS (Irish Health Repository)

    Keogan, M T

    2009-04-01

    Patients presenting with recurrent orogenital ulcers may have complex aphthosis, Behçet\\'s disease, secondary complex aphthosis (e.g. Reiter\\'s syndrome, Crohn\\'s disease, cyclical neutropenia) or non-aphthous disease (including bullous disorders, erythema multiforme, erosive lichen planus). Behçet\\'s syndrome is a multi-system vasculitis of unknown aetiology for which there is no diagnostic test. Diagnosis is based on agreed clinical criteria that require recurrent oral ulcers and two of the following: recurrent genital ulcers, ocular inflammation, defined skin lesions and pathergy. The condition can present with a variety of symptoms, hence a high index of suspicion is necessary. The most common presentation is with recurrent mouth ulcers, often with genital ulcers; however, it may take some years before diagnostic criteria are met. All patients with idiopathic orogenital ulcers should be kept under review, with periodic focused assessment to detect evolution into Behçet\\'s disease. There is often a delay of several years between patients fulfilling diagnostic criteria and a diagnosis being made, which may contribute to the morbidity of this condition. Despite considerable research effort, the aetiology and pathogenesis of this condition remains enigmatic.

  3. Quality assurance (QA) training at Westinghouse including innovative approaches for achieving an effective QA programme and establishing constructive interaction

    International Nuclear Information System (INIS)

    Experience of the Westinghouse Water Reactors Division with indoctrination and training of quality engineers includes training of personnel from Westinghouse divisions in the USA and overseas as well as of customers' personnel. A written plan is prepared for each trainee in order to fit the training to the individual's needs, and to cover the full range of information and activities. The trainee is also given work assignments, working closely with experienced quality engineers. He may prepare inspection plans and audit check lists, assist in the preparation of QA training modules, write procedures, and perform supplier surveillance and data analyses, or make special studies of operating systems. The trainee attends seminars and special courses on work-related technical subjects. Throughout the training period, emphasis is placed on inculcating an attitude of team work in the trainee so that the result of the training is the achievement of both quality and productivity. Certification is extended (given that education/experience/skill requirements are met) to such functions as mechanical equipment quality engineering, electrical equipment quality engineering, and start-up and testing quality engineering. A well-trained quality engineer is equipped to provide technical assistance to other disciplines and, through effective co-operation with others, contributes to the success of the organization's endeavours. (author)

  4. Organic solvent wetting properties of UV and plasma treated ZnO nanorods: printed electronics approach

    KAUST Repository

    Sliz, Rafal

    2012-09-13

    Due to low manufacturing costs, printed organic solar cells are on the short-list of renewable and environmentally- friendly energy production technologies of the future. However, electrode materials and each photoactive layer require different techniques and approaches. Printing technologies have attracted considerable attention for organic electronics due to their potentially high volume and low cost processing. A case in point is the interface between the substrate and solution (ink) drop, which is a particularly critical issue for printing quality. In addition, methods such as UV, oxygen and argon plasma treatments have proven suitable to increasing the hydrophilicity of treated surfaces. Among several methods of measuring the ink-substrate interface, the simplest and most reliable is the contact angle method. In terms of nanoscale device applications, zinc oxide (ZnO) has gained popularity, owing to its physical and chemical properties. In particular, there is a growing interest in exploiting the unique properties that the so-called nanorod structure exhibits for future 1-dimensional opto-electronic devices. Applications, such as photodiodes, thin-film transistors, sensors and photo anodes in photovoltaic cells have already been demonstrated. This paper presents the wettability properties of ZnO nanorods treated with UV illumination, oxygen and argon plasma for various periods of time. Since this work concentrates on solar cell applications, four of the most common solutions used in organic solar cell manufacture were tested: P3HT:PCBM DCB, P3HT:PCBM CHB, PEDOT:PSS and water. The achieved results prove that different treatments change the contact angle differently. Moreover, solvent behaviour varied uniquely with the applied treatment. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  5. Accurate determination of ultra-trace impurities, including europium, in ultra-pure barium carbonate materials through inductively coupled plasma-tandem mass spectrometry

    Science.gov (United States)

    Wu, Shuchao; Zeng, Xiangcheng; Dai, Xuefeng; Hu, Yongping; Li, Gang; Zheng, Cunjiang

    2016-09-01

    Impurities, especially ultra-trace europium (Eu), in ultra-pure barium carbonate materials were accurately determined through inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS). Two reaction modes, namely, mass shift (with O2 as reaction gas) and on-mass modes(with NH3/He and He as reaction gases), were extensively investigated using Eu+ as target analyte. The use of Eu+ → EuO2+, instead of Eu+ → EuO+, as ion pairs in mass shift mode eliminated polyatomic interferences based on Ba matrix ions (135Ba16O2+ on 151Eu16O+ and 137Ba16O2+ on 153Eu16O+). This procedure exhibited enhanced sensitivity and selectivity. When the ICP-MS/MS was operated in NH3 on-mass mode, Eu+ can be determined in its original mass in interference-free conditions because NH3 did not react with Eu+ but with BaO+ to form a neutral product (BaO). The two reaction modes, especially NH3 on mass mode, were validated to be accurate because their resultant isotope ratios of 153Eu/151Eu matched well with that of the natural abundance ratio. The proposed ICP-MS/MS method is a sensitive technique with a limit of detection as low as 2.0 ng L- 1 for 153Eu+. Compared with conventional single-quadrupole (SQ) ICP-MS, both NH3 on-mass mode and O2 mass shift mode in ICP-MS/MS can be used to accurately determine Eu+ in ultra-pure BaCO3 materials. The detected concentration of Eu+ was 4.0 ng L- 1 to 15 ng L- 1, with spiked recoveries ranging from 100%-110%. ICP-MS/MS was also used to eliminate polyatomic interferences, particularly Ba-based interferences, prior to measurement of Gd and Sm. Impurities, including Na, Mg, Al, K, Mn, Fe, Cr, Sr, and Cs, in ultra-pure BaCO3 materials were also determined using ICP-MS/MS in conventional SQ mode.

  6. General relativistic radiative transfer in hot astrophysical plasmas a characteristic approach

    CERN Document Server

    Zane, S; Nobili, L; Erna, M; Zane, Silvia; Turolla, Roberto; Nobili, Luciano; Erna, Myris

    1996-01-01

    In this paper we present a characteristic method for solving the transfer equation in differentially moving media in a curved spacetime. The method is completely general, but its capabilities are exploited at best in presence of symmetries, when the existence of conserved quantities allows to derive analytical expressions for the photon trajectories in phase space. In spherically--symmetric, stationary configurations the solution of the transfer problem is reduced to the integration of a single ordinary differential equation along the bi--parametric family of characteristic rays. Accurate expressions for the radiative processes relevant to continuum transfer in a hot astrophysical plasma have been used in evaluating the source term, including relativistic e--p, e--e bremsstrahlung and Compton scattering. A numerical code for the solution of the transfer problem in moving media in a Schwarzschild spacetime has been developed and tested. Some applications, concerning ``hot'' and ``cold'' accretion onto non--rot...

  7. Is the societal approach wide enough to include relatives? Incorporating relatives' costs and effects in a cost-effectiveness analysis.

    Science.gov (United States)

    Davidson, Thomas; Levin, Lars-Ake

    2010-01-01

    It is important for economic evaluations in healthcare to cover all relevant information. However, many existing evaluations fall short of this goal, as they fail to include all the costs and effects for the relatives of a disabled or sick individual. The objective of this study was to analyse how relatives' costs and effects could be measured, valued and incorporated into a cost-effectiveness analysis. In this article, we discuss the theories underlying cost-effectiveness analyses in the healthcare arena; the general conclusion is that it is hard to find theoretical arguments for excluding relatives' costs and effects if a societal perspective is used. We argue that the cost of informal care should be calculated according to the opportunity cost method. To capture relatives' effects, we construct a new term, the R-QALY weight, which is defined as the effect on relatives' QALY weight of being related to a disabled or sick individual. We examine methods for measuring, valuing and incorporating the R-QALY weights. One suggested method is to estimate R-QALYs and incorporate them together with the patient's QALY in the analysis. However, there is no well established method as yet that can create R-QALY weights. One difficulty with measuring R-QALY weights using existing instruments is that these instruments are rarely focused on relative-related aspects. Even if generic quality-of-life instruments do cover some aspects relevant to relatives and caregivers, they may miss important aspects and potential altruistic preferences. A further development and validation of the existing caregiving instruments used for eliciting utility weights would therefore be beneficial for this area, as would further studies on the use of time trade-off or Standard Gamble methods for valuing R-QALY weights. Another potential method is to use the contingent valuation method to find a monetary value for all the relatives' costs and effects. Because cost-effectiveness analyses are used for

  8. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  9. Comparison of approaches to Total Quality Management. Including an examination of the Department of Energy`s position on quality management

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, C.T.

    1994-03-01

    This paper presents a comparison of several qualitatively different approaches to Total Quality Management (TQM). The continuum ranges from management approaches that are primarily standards -- with specific guidelines, but few theoretical concepts -- to approaches that are primarily philosophical, with few specific guidelines. The approaches to TQM discussed in this paper include the International Organization for Standardization (ISO) 9000 Standard, the Malcolm Baldrige National Quality Award, Senge`s the Learning Organization, Watkins and Marsick`s approach to organizational learning, Covey`s Seven Habits of Highly Successful People, and Deming`s Fourteen Points for Management. Some of these approaches (Deming and ISO 9000) are then compared to the DOE`s official position on quality management and conduct of operations (DOE Orders 5700.6C and 5480.19). Using a tabular format, it is shown that while 5700.6C (Quality Assurance) maps well to many of the current approaches to TQM, DOE`s principle guide to management Order 5419.80 (Conduct of Operations) has many significant conflicts with some of the modern approaches to continuous quality improvement.

  10. Dark matter inelastic up-scattering with the interstellar plasma: A new source of x-ray lines, including at 3.5 keV

    Science.gov (United States)

    D'Eramo, Francesco; Hambleton, Kevin; Profumo, Stefano; Stefaniak, Tim

    2016-05-01

    We explore the phenomenology of a class of models where the dark matter particle can inelastically up-scatter to a heavier excited state via off-diagonal dipolar interactions with the interstellar plasma (gas or free electrons). The heavier particle then rapidly decays back to the dark matter particle plus a quasimonochromatic photon. For the process to occur at appreciable rates, the mass splitting between the heavier state and the dark matter must be comparable to, or smaller than, the kinetic energy of particles in the plasma. As a result, the predicted photon line falls in the soft x-ray range, or, potentially, at arbitrarily lower energies. We explore experimental constraints from cosmology and particle physics, and present accurate calculations of the dark matter thermal relic density and of the flux of monochromatic x rays from thermal plasma excitation. We find that the model provides a natural explanation for the observed 3.5 keV line from clusters of galaxies and from the Galactic center, and is consistent with null detections of the line from dwarf galaxies. The unique line shape, which will be resolved by future observations with the Hitomi (formerly Astro-H) satellite, and the predicted unique morphology and target-temperature dependence will enable easy discrimination of this class of models versus other scenarios for the generation of the 3.5 keV line or of any other unidentified line across the electromagnetic spectrum.

  11. Dark Matter Inelastic Up-Scattering with the Interstellar Plasma: An Exciting New Source of X-Ray Lines, including at 3.5 keV

    CERN Document Server

    D'Eramo, Francesco; Profumo, Stefano; Stefaniak, Tim

    2016-01-01

    We explore the phenomenology of a class of models where the dark matter particle can inelastically up-scatter to a heavier excited state via off-diagonal dipolar interactions with the interstellar plasma (gas or free electrons). The heavier particle then rapidly decays back to the dark matter particle plus a quasi-monochromatic photon. For the process to occur at appreciable rates, the mass splitting between the heavier state and the dark matter must be comparable to, or smaller than, the kinetic energy of particles in the plasma. As a result, the predicted photon line falls in the soft X-ray range, or, potentially, at arbitrarily lower energies. We explore experimental constraints from cosmology and particle physics, and present accurate calculations of the dark matter thermal relic density and of the flux of monochromatic X-rays from thermal plasma excitation. We find that the model provides a natural explanation for the observed 3.5 keV line from clusters of galaxies and from the Galactic center, and is co...

  12. Demonstrating an Approach for Including Pesticide Use in Life Cycle Assessment: Estimating Human and Ecosystem Toxicity of Pesticide Use in Midwest Corn Farming

    Science.gov (United States)

    Purpose This study demonstrates an approach to assess human health and ecotoxicity impacts of pesticide use by including multiple environmental pathways and various exposure routes using the case of corn grown for bio-based fuel or chemical production in US Midwestern states.Meth...

  13. Demonstrating an approach for including pesticide use in life-cycle assessment: Estimating human and ecosystem toxicity of pesticide use in Midwest corn farming

    Science.gov (United States)

    PurposeThis study demonstrates an approach to assess human health and ecotoxicity impacts of pesticide use by including multiple environmental pathways and various exposure routes using the case of corn grown for bio-based fuel or chemical production in US Midwestern states.Metho...

  14. Effective-action approach to wave propagation in scalar QED plasmas

    Science.gov (United States)

    Shi, Yuan; Fisch, Nathaniel J.; Qin, Hong

    2016-07-01

    A relativistic quantum field theory with nontrivial background fields is developed and applied to study waves in plasmas. The effective action of the electromagnetic 4-potential is calculated ab initio from the standard action of scalar QED using path integrals. The resultant effective action is gauge invariant and contains nonlocal interactions, from which gauge bosons acquire masses without breaking the local gauge symmetry. To demonstrate how the general theory can be applied, we give two examples: a cold unmagnetized plasma and a cold uniformly magnetized plasma. Using these two examples, we show that all linear waves well known in classical plasma physics can be recovered from relativistic quantum results when taking the classical limit. In the opposite limit, classical wave dispersion relations are modified substantially. In unmagnetized plasmas, longitudinal waves propagate with nonzero group velocities even when plasmas are cold. In magnetized plasmas, anharmonically spaced Bernstein waves persist even when plasmas are cold. These waves account for cyclotron absorption features observed in spectra of x-ray pulsars. Moreover, cutoff frequencies of the two nondegenerate electromagnetic waves are red-shifted by different amounts. These corrections need to be taken into account in order to correctly interpret diagnostic results in laser plasma experiments.

  15. Integrated approach for low-temperature synthesis of high-quality silicon nitride films in PECVD using RF-UHF hybrid plasmas

    Science.gov (United States)

    Sahu, B. B.; Shin, Kyung S.; Han, Jeon G.

    2016-02-01

    This study investigates low-temperature plasma nitriding of hydrogenated silicon (SiN x :H) film in radio frequency (RF) and RF-ultra-high frequency (UHF) hybrid plasmas. To study the optimized conditions for the deposition of SiN x :H film, this work adopts a systematic plasma diagnostic approach in the nitrogen-silane and nitrogen-silane-ammonia plasmas. This work also evaluates the capability of plasma and radical formation by utilizing different plasma sources in the PECVD process. For the plasma diagnostics, we have purposefully used the combination of optical emission spectroscopy (OES), intensified CCD (ICCD) camera, vacuum ultraviolet absorption spectroscopy (VUVAS), and RF compensated Langmuir probe (LP). Data reveal that there is significant enhancement in the atomic nitrogen radicals, plasma densities, and film properties using the hybrid plasmas. Measurements show that addition of a small amount of NH3 can significantly reduce the electron temperature, plasma, and radical density. Also, optical and chemical properties of the deposited films are investigated on the basis of plasma diagnostics. Good quality SiN x :H films, with atomic nitrogen to hydrogen ratio of 4:1, are fabricated. The plasma chemistry of the hybrid plasmas is also discussed for its utility for plasma applications.

  16. New approaches for the reduction of plasma arc drop in second-generation thermionic converters. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hatziprokopiou, M.E.; Shaw, D.T.

    1981-03-31

    Investigations of ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter are described. The changes in plasma density and temperature within the converter have been studied under the influence of several promising auxiliary ionization candidate sources. Three novel approaches of external cesium ion generation have been investigated in some detail, namely vibrationally excited N/sub 2/ as an energy source of ionization of Cs ions in a DC discharge, microwave power as a means of resonant sustenance of the cesium plasma, and ion generation in a pulse N/sub 2/-Cs mixture. The experimental data obtained and discussed show that all three techniques - i.e. the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave power - have considerable promise as schemes in auxiliary ion generation applicable to the advanced thermionic energy converter.

  17. New approach to controlling impurity contamination of a plasma-gun-produced compact torus

    International Nuclear Information System (INIS)

    The presence of impurity ions, notably carbon and oxygen, has been determined to be a major factor limiting the lifetime of field-reversed plasma entities produced by coaxial plasma guns such as the Beta II gun at LLNL. Similar problems are encountered in other toroidal plasmas, e.g. those in tokamaks. However, the solution employed there, discharge cleaning, followed by initiation of the plasma at low density (where impurity radiation losses are exceeded by ohmic heating rates) is not applicable here. This note discusses a proposed means for drastically reducing the level of impurities. (These are believed to be evolved from the gun electrode surfaces as a result of thermal shock associated with UV emission from the gun plasma). The idea: take advantage of the UV pulse preferentially to release hydrogen from the electrode surfaces. These surfaces are to be coated with a few-micron-thick layer of titanium, outgassed by preheating and subsequently loaded with hydrogen

  18. Overview of the data-acquisition system (including shielding, isolation and grounding) on the Beta II field-reversed plasma-gun experiment

    International Nuclear Information System (INIS)

    Computer-supported acquisition, analysis, and storage of mirror fusion experimental data requires the solution of several problems. The data must be gathered with a minimum amount of noise, and transients must be excluded from the computer so that it can function properly. On Beta II (which was an experiment to produce field-reversed plasma rings from a coaxial plasma gun) the diagnostic system was planned to provide the shielding and isolation necessary to solve these two problems. The Beta II system has been in operation for about two years and provides 300-channel capacity, CAMAC interfaced, to a Hewlett Packard 21MX computer. The system routinely handles signals ranging from 1 mV to 50 kV, with bandwidths from .05 Hz to 10 MHz. The data are captured by transient recorders during a shot, then transferred to the computer. The computer stores the data on disc for immediate processing and on tape for long-term storage. Processed data from any number of channels (usually 20 to 30) is plotted between shots for immediate review. The rest of the data is processed and plotted during off hours

  19. The field line map approach for simulations of magnetically confined plasmas

    CERN Document Server

    Stegmeir, Andreas; Maj, Omar; Hallatschek, Klaus; Lackner, Karl

    2015-01-01

    In the presented field line map approach the simulation domain of a tokamak is covered with a cylindrical grid, which is Cartesian within poloidal planes. Standard finite-difference methods can be used for the discretisation of perpendicular (w.r.t.~magnetic field lines) operators. The characteristic flute mode property $\\left(k_{\\parallel}\\ll k_{\\perp}\\right)$ of structures is exploited computationally by a grid sparsification in the toroidal direction. A field line following discretisation of parallel operators is then required, which is achieved via a finite difference along magnetic field lines. This includes field line tracing and interpolation or integration. The main emphasis of this paper is on the discretisation of the parallel diffusion operator. Based on the support operator method a scheme is constructed which exhibits only very low numerical perpendicular diffusion. The schemes are implemented in the new code GRILLIX, and extensive benchmarks are presented which show the validity of the approach ...

  20. Nanoporous Silver Film Fabricated by Oxygen Plasma: A Facile Approach for SERS Substrates.

    Science.gov (United States)

    Ma, Chaoxiong; Trujillo, Michael J; Camden, Jon P

    2016-09-14

    Nanoporous metal films are promising substrates for surfaced-enhanced Raman scattering (SERS) measurement, owing to their homogeneity, large surface area, and abundant hot-spots. Herein, a facile procedure was developed to fabricate nanoporous Ag film on various substrate surfaces. Thermally deposited Ag film was first treated with O2 plasma, resulting in porous Ag/AgxO film (AgxO-NF) with nanoscale feature. Sodium citrate was then used to reduce AgxO to Ag, forming nanoporous Ag film (AgNF) with similar morphology. The AgNF substrate demonstrates 30-fold higher Raman intensity than Ag film over polystyrene nanospheres (d = 600 nm) using 4-mercaptobenzoic acid (4-MBA) as the sensing molecule. Comparing with ordinary Raman measurement on 4-MBA solution, an enhancement factor of ∼6 × 10(6) was determined for AgNF. The AgNF substrate was evaluated for benzoic acid, 4-nitrophenol, and 2-mercaptoethanesulfonate, showing high SERS sensitivity for chemicals that bind weakly to Ag surface and molecules with relatively small Raman cross section at micromolar concentration. In addition to its simplicity, the procedure can be applied to various materials such as transparency film, filter paper, hard polystyrene film, and aluminum foil, revealing similar Raman sensitivity. By testing the durability of the substrate, we found that the AgxO films can be stored in ambient conditions for more than 90 days and still deliver the same SERS intensity if the films are treated with sodium citrate before use. These results demonstrate the advantage of the proposed approach for mass production of low-cost, sensitive, and durable SERS substrates. The transferable nature of these AgNF to different flexible surfaces also allows their easy integration with other sensing schemes.

  1. Removing biofilms from microstructured titanium ex vivo: a novel approach using atmospheric plasma technology.

    Science.gov (United States)

    Rupf, Stefan; Idlibi, Ahmad Nour; Marrawi, Fuad Al; Hannig, Matthias; Schubert, Andreas; von Mueller, Lutz; Spitzer, Wolfgang; Holtmann, Henrik; Lehmann, Antje; Rueppell, Andre; Schindler, Axel

    2011-01-01

    The removal of biofilms from microstructured titanium used for dental implants is a still unresolved challenge. This experimental study investigated disinfection and removal of in situ formed biofilms from microstructured titanium using cold atmospheric plasma in combination with air/water spray. Titanium discs (roughness (Ra): 1.96 µm) were exposed to human oral cavities for 24 and 72 hours (n = 149 each) to produce biofilms. Biofilm thickness was determined using confocal laser scanning microscopy (n = 5 each). Plasma treatment of biofilms was carried out ex vivo using a microwave-driven pulsed plasma source working at temperatures from 39 to 43°C. Following plasma treatment, one group was air/water spray treated before re-treatment by second plasma pulses. Vital microorganisms on the titanium surfaces were identified by contact culture (Rodac agar plates). Biofilm presence and bacterial viability were quantified by fluorescence microscopy. Morphology of titanium surfaces and attached biofilms was visualized by scanning electron microscopy (SEM). Total protein amounts of biofilms were colorimetrically quantified. Untreated and air/water treated biofilms served as controls. Cold plasma treatment of native biofilms with a mean thickness of 19 µm (24 h) to 91 µm (72 h) covering the microstructure of the titanium surface caused inactivation of biofilm bacteria and significant reduction of protein amounts. Total removal of biofilms, however, required additional application of air/water spray, and a second series of plasma treatment. Importantly, the microstructure of the titanium discs was not altered by plasma treatment. The combination of atmospheric plasma and non-abrasive air/water spray is applicable for complete elimination of oral biofilms from microstructured titanium used for dental implants and may enable new routes for the therapy of periimplant disease.

  2. Removing biofilms from microstructured titanium ex vivo: a novel approach using atmospheric plasma technology.

    Directory of Open Access Journals (Sweden)

    Stefan Rupf

    Full Text Available The removal of biofilms from microstructured titanium used for dental implants is a still unresolved challenge. This experimental study investigated disinfection and removal of in situ formed biofilms from microstructured titanium using cold atmospheric plasma in combination with air/water spray. Titanium discs (roughness (Ra: 1.96 µm were exposed to human oral cavities for 24 and 72 hours (n = 149 each to produce biofilms. Biofilm thickness was determined using confocal laser scanning microscopy (n = 5 each. Plasma treatment of biofilms was carried out ex vivo using a microwave-driven pulsed plasma source working at temperatures from 39 to 43°C. Following plasma treatment, one group was air/water spray treated before re-treatment by second plasma pulses. Vital microorganisms on the titanium surfaces were identified by contact culture (Rodac agar plates. Biofilm presence and bacterial viability were quantified by fluorescence microscopy. Morphology of titanium surfaces and attached biofilms was visualized by scanning electron microscopy (SEM. Total protein amounts of biofilms were colorimetrically quantified. Untreated and air/water treated biofilms served as controls. Cold plasma treatment of native biofilms with a mean thickness of 19 µm (24 h to 91 µm (72 h covering the microstructure of the titanium surface caused inactivation of biofilm bacteria and significant reduction of protein amounts. Total removal of biofilms, however, required additional application of air/water spray, and a second series of plasma treatment. Importantly, the microstructure of the titanium discs was not altered by plasma treatment. The combination of atmospheric plasma and non-abrasive air/water spray is applicable for complete elimination of oral biofilms from microstructured titanium used for dental implants and may enable new routes for the therapy of periimplant disease.

  3. Nosocomial infections-a new approach towards preventive medicine using plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Morfill, G E; Shimizu, T; Steffes, B; Schmidt, H-U [Max-Planck Institute for extraterrestrial physics, Giessenbachstrasse, D-85748 Garching (Germany); Hospital Munich Schwabing, Koelner Platz 1, D-80804 Muenchen (Germany)], E-mail: gem@mpe.mpg.de

    2009-11-15

    A new, very efficient, large area scalable and robust electrode design for plasma production in air at atmosphere pressures has been developed and tested. This has made the development of a 'plasma dispenser' for hospital disinfection possible, which has certain advantages over current fluid disinfection systems. The properties of this device are presented, in particular the bactericidal and fungicidal efficiency, and the advantages are described. Such plasma dispensers could play an important role in the future fight against the alarming and growing threat posed by nosocomial (=hospital and community associated) bacterial infections.

  4. Nosocomial infections—a new approach towards preventive medicine using plasmas

    Science.gov (United States)

    Morfill, G. E.; Shimizu, T.; Steffes, B.; Schmidt, H.-U.

    2009-11-01

    A new, very efficient, large area scalable and robust electrode design for plasma production in air at atmosphere pressures has been developed and tested. This has made the development of a 'plasma dispenser' for hospital disinfection possible, which has certain advantages over current fluid disinfection systems. The properties of this device are presented, in particular the bactericidal and fungicidal efficiency, and the advantages are described. Such plasma dispensers could play an important role in the future fight against the alarming and growing threat posed by nosocomial (=hospital and community associated) bacterial infections.

  5. 'Plasma Camp': A Different Approach to Professional Development for Physics Teachers

    Energy Technology Data Exchange (ETDEWEB)

    Andrew Post-Zwicker and Nicholas R. Guilbert

    1998-12-01

    The Plasma Physics and Fusion Energy Institute ('Plasma Camp') was inaugurated in 1998 as a way to address two areas of concern in the professional development of high-school physics teachers: involving teachers in the theory and methods of a current area of research in physics and connecting the research experience back into the classroom. The Institute, run jointly by a scientist and a teacher, immersed high-school teachers from across the country in laboratory investigations and in pedagogical projects for two weeks at Princeton University's Plasma Physics Laboratory. The goals, structure, and initial outcomes of the Institute are discussed.

  6. Multiscale approach including microfibril scale to assess elastic constants of cortical bone based on neural network computation and homogenization method

    OpenAIRE

    Barkaoui, Abdelwahed; Chamekh, Abdessalem; Tarek, Merzouki; Hambli, Ridha; Ali, Mkaddem

    2013-01-01

    The complexity and heterogeneity of bone tissue require a multiscale modelling to understand its mechanical behaviour and its remodelling mechanisms. In this paper, a novel multiscale hierarchical approach including microfibril scale based on hybrid neural network computation and homogenisation equations was developed to link nanoscopic and macroscopic scales to estimate the elastic properties of human cortical bone. The multiscale model is divided into three main phases: (i) in step 0, the e...

  7. Marine geodesy a multipurpose approach to solve oceanic problems. [including submersible navigation under iced seas, demarcation and determination of boundaries in deep ocean, tsunamis, and ecology

    Science.gov (United States)

    Saxena, N.

    1974-01-01

    Various current and future problem areas of marine geodesy are identified. These oceanic problem areas are highly diversified and include submersible navigation under ice seas, demarcation and determination of boundaries in deep ocean, tsunamis, ecology, etc., etc. Their achieved as well as desired positional accuracy estimates, based upon publications and discussions, are also given. A multipurpose approach to solve these problems is described. An optimum configuration of an ocean-bottom control-net unit is provided.

  8. An effective field theory approach to the stabilization of 8Be in a QED plasma

    Science.gov (United States)

    Yao, Xiaojun; Mehen, Thomas; Müller, Berndt

    2016-07-01

    We use effective field theory to study the α –α resonant scattering in a finite-temperature QED plasma. The static plasma screening effect causes the resonance state 8Be to live longer and eventually leads to the formation of a bound state when {m}{{D}}≳ 0.3 {{MeV}}. We speculate that this effect may have implications on the rates of cosmologically and astrophysically relevant nuclear reactions involving α particles.

  9. Fluorescence interference contrast based approach to study real time interaction of melittin with plasma membranes

    Science.gov (United States)

    Gupta, Sharad; Gui, Dong; Zandi, Roya; Gill, Sarjeet; Mohideen, Umar

    2014-03-01

    Melittin is an anti-bacterial and hemolytic toxic peptide found in bee venom. Cell lysis behavior of peptides has been widely investigated, but the exact interaction mechanism of lytic peptides with lipid membranes and its constituents has not been understood completely. In this paper we study the melittin interaction with lipid plasma membranes in real time using non-invasive and non-contact fluorescence interference contrast microscopy (FLIC). Particularly the interaction of melittin with plasma membranes was studied in a controlled molecular environment, where these plasma membrane were composed of saturated lipid, 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) and unsaturated lipid, 1,2-dioleoyl-sn-glycero-3-phosphocholine(DOPC) with and without cholesterol. We found out that melittin starts to form nanometer size pores in the plasma membranes shortly after interacting with membranes. But the addition of cholesterol in plasma membrane slows down the pore formation process. Our results show that inclusion of cholesterol to the plasma membranes make them more resilient towards pore formation and lysis of membrane.

  10. Modeling function-perfusion behavior in liver lobules including tissue, blood, glucose, lactate and glycogen by use of a coupled two-scale PDE-ODE approach.

    Science.gov (United States)

    Ricken, T; Werner, D; Holzhütter, H G; König, M; Dahmen, U; Dirsch, O

    2015-06-01

    This study focuses on a two-scale, continuum multicomponent model for the description of blood perfusion and cell metabolism in the liver. The model accounts for a spatial and time depending hydro-diffusion-advection-reaction description. We consider a solid-phase (tissue) containing glycogen and a fluid-phase (blood) containing glucose as well as lactate. The five-component model is enhanced by a two-scale approach including a macroscale (sinusoidal level) and a microscale (cell level). The perfusion on the macroscale within the lobules is described by a homogenized multiphasic approach based on the theory of porous media (mixture theory combined with the concept of volume fraction). On macro level, we recall the basic mixture model, the governing equations as well as the constitutive framework including the solid (tissue) stress, blood pressure and solutes chemical potential. In view of the transport phenomena, we discuss the blood flow including transverse isotropic permeability, as well as the transport of solute concentrations including diffusion and advection. The continuum multicomponent model on the macroscale finally leads to a coupled system of partial differential equations (PDE). In contrast, the hepatic metabolism on the microscale (cell level) was modeled via a coupled system of ordinary differential equations (ODE). Again, we recall the constitutive relations for cell metabolism level. A finite element implementation of this framework is used to provide an illustrative example, describing the spatial and time-depending perfusion-metabolism processes in liver lobules that integrates perfusion and metabolism of the liver.

  11. A combined multibody and finite element approach for dynamic interaction analysis of high-speed train and railway structure including post-derailment behavior during an earthquake

    International Nuclear Information System (INIS)

    A combined multibody and finite element approach is given to solve the dynamic interaction of a Shinkansen train (high-speed train in Japan) and the railway structure including post-derailment during an earthquake effectively. The motion of the train is expressed in multibody dynamics. Efficient mechanical models to express interactions between wheel and track structure including post-derailment are given. Rail and track elements expressed in multibody dynamics and FEM are given to solve contact problems between wheel and long railway components effectively. The motion of a railway structure is modeled with various finite elements and rail and track elements. The computer program has been developed for the dynamic interaction analysis of a Shinkansen train and railway structure including post derailment during an earthquake. Numerical examples are demonstrated.

  12. Controlled Distribution and Clustering of Silver in Ag-DLC Nanocomposite Coatings Using a Hybrid Plasma Approach.

    Science.gov (United States)

    Cloutier, M; Turgeon, S; Busby, Y; Tatoulian, M; Pireaux, J-J; Mantovani, D

    2016-08-17

    Incorporation of selected metallic elements into diamond-like carbon (DLC) has emerged as an innovative approach to add unique functional properties to DLC coatings, thus opening up a range of new potential applications in fields as diverse as sensors, tribology, and biomaterials. However, deposition by plasma techniques of metal-containing DLC coatings with well-defined structural properties and metal distribution is currently hindered by the limited understanding of their growth mechanisms. We report here a silver-incorporated diamond-like carbon coating (Ag-DLC) prepared in a hybrid plasma reactor which allowed independent control of the metal content and the carbon film structure and morphology. Morphological and chemical analyses of Ag-DLC films were performed by atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. The vertical distribution of silver from the surface toward the coating bulk was found to be highly inhomogeneous due to top surface segregation and clustering of silver nanoparticles. Two plasma parameters, the sputtered Ag flux and ion energy, were shown to influence the spatial distribution of silver particles. On the basis of these findings, a mechanism for Ag-DLC growth by plasma was proposed. PMID:27454833

  13. Effect of dense plasmas on exchange-energy shifts in highly charged ions: An alternative approach for arbitrary perturbation potentials

    Energy Technology Data Exchange (ETDEWEB)

    Rosmej, F. [Sorbonne Universites, Pierre et Marie Curie, UMR 7605, case 128, 4 place Jussieu, F-75252 Paris (France); Ecole Polytechnique, Laboratoire pour l' Utilisation des Lasers Intenses LULI, Physique Atomique dans les Plasmas Denses PAPD, F-91228 Palaiseau (France); Bennadji, K. [Sorbonne Universites, Pierre et Marie Curie, UMR 7605, case 128, 4 place Jussieu, F-75252 Paris (France); ExtreMe Matter Institute EMMI, GSI Helmholtz Centre of Heavy Ion Research, Planckstrasse 1, D-64291 Darmstadt (Germany); Lisitsa, V. S. [Russian Research Center Kurchatov, Laboratory of Radiation Theory, Kurchatov Square 1, 123182 Moscow (Russian Federation)

    2011-09-15

    An alternative method of calculation of dense plasma effects on exchange-energy shifts {Delta}E{sub x} of highly charged ions is proposed which results in closed expressions for any plasma or perturbation potential. The method is based on a perturbation theory expansion for the inner atomic potential produced by charged plasma particles employing the Coulomb Green function method. This approach allows us to obtain analytic expressions and scaling laws with respect to the electron temperature T, density n{sub e}, and nuclear charge Z. To demonstrate the power of the present method, two specific models were considered in detail: the ion sphere model (ISM) and the Debye screening model (DSM). We demonstrate that analytical expressions can be obtained even for the finite temperature ISM. Calculations have been carried out for the singlet 1s2p{sup 1} P{sub 1} and triplet 1s2p{sup 3} P{sub 1} configurations of He-like ions with charge Z that can be observed in dense plasmas via the He-like resonance and intercombination lines. Finally we discuss recently available purely numerical calculations and experimental data.

  14. Plasmas for medicine

    Science.gov (United States)

    von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.

    2013-09-01

    Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) “Indirect” use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous

  15. An Effective Field Theory Approach to the Stabilization of $^8$Be in a QED Plasma

    CERN Document Server

    Yao, Xiaojun; Müller, Berndt

    2016-01-01

    We use effective field theory to study the $\\mathrm{\\alpha}$-$\\mathrm{\\alpha}$ resonance scattering in a finite-temperature QED plasma. The plasma screening effect causes the resonance state $^8$Be to live longer and eventually leads to the formation of a bound state when $m_D\\gtrsim 0.3$ MeV. We speculate that this effect may contribute to a possible solution to the problem of the primordial $^7$Li abundance. It also has applications in other nuclear fusion processes.

  16. The singular approach for processing polarization-inhomogeneous laser images of blood plasma layers

    Science.gov (United States)

    Angelsky, P. O.; Ushenko, A. G.; Dubolazov, A. V.; Sidor, M. I.; Bodnar, G. B.; Koval, G.; Trifonyuk, L.

    2013-04-01

    We present in this work the results of an investigation to analyse the coordinate distributions of azimuths and ellipticity of polarization (polarization maps) in laser images of blood plasma layers for three groups of patients: healthy (group 1), mastopathy (group 2) and breast cancer (group 3). To characterize polarization maps for all groups of samples we use three groups of parameters: statistical moments of the first to fourth orders, autocorrelation functions and logarithmic dependences for power spectra related to distributions of azimuths and ellipticity of polarization inherent to laser images of blood plasma. We ascertain the criteria for diagnosis and differentiation of pathological changes of the breast.

  17. The singular approach for processing polarization-inhomogeneous laser images of blood plasma layers

    International Nuclear Information System (INIS)

    We present in this work the results of an investigation to analyse the coordinate distributions of azimuths and ellipticity of polarization (polarization maps) in laser images of blood plasma layers for three groups of patients: healthy (group 1), mastopathy (group 2) and breast cancer (group 3). To characterize polarization maps for all groups of samples we use three groups of parameters: statistical moments of the first to fourth orders, autocorrelation functions and logarithmic dependences for power spectra related to distributions of azimuths and ellipticity of polarization inherent to laser images of blood plasma. We ascertain the criteria for diagnosis and differentiation of pathological changes of the breast. (paper)

  18. Deformation integrity monitoring for GNSS positioning services including local, regional and large scale hazard monitoring - the Karlsruhe approach and software(MONIKA)

    Science.gov (United States)

    Jaeger, R.

    2007-05-01

    GNSS-positioning services like SAPOS/ascos in Germany and many others in Europe, America and worldwide, usually yield in a short time their interdisciplinary and country-wide use for precise geo-referencing, replacing traditional low order geodetic networks. So it becomes necessary that possible changes of the reference stations' coordinates are detected ad hoc. The GNSS-reference-station MONitoring by the KArlsruhe approach and software (MONIKA) are designed for that task. The developments at Karlsruhe University of Applied Sciences in cooperation with the State Survey of Baden-Württemberg are further motivated by a the official resolution of the German state survey departments' association (Arbeitsgemeinschaft der Vermessungsverwaltungen Deutschland (AdV)) 2006 on coordinate monitoring as a quality-control duty of the GNSS-positioning service provider. The presented approach can - besides the coordinate control of GNSS-positioning services - also be used to set up any GNSS-service for the tasks of an area-wide geodynamical and natural disaster-prevention service. The mathematical model of approach, which enables a multivariate and multi-epochal design approach, is based on the GNSS-observations input of the RINEX-data of the GNSS service, followed by fully automatic processing of baselines and/or session, and a near-online setting up of epoch-state vectors and their covariance-matrices in a rigorous 3D network adjustment. In case of large scale and long-term monitoring situations, geodynamical standard trends (datum-drift, plate-movements etc.) are accordingly considered and included in the mathematical model of MONIKA. The coordinate-based deformation monitoring approach, as third step of the stepwise adjustments, is based on the above epoch-state vectors, and - splitting off geodynamics trends - hereby on a multivariate and multi-epochal congruency testing. So far, that no other information exists, all points are assumed as being stable and congruent reference

  19. Molecular Classification and Pharmacogenetics of Primary Plasma Cell Leukemia: An Initial Approach toward Precision Medicine.

    Science.gov (United States)

    Simeon, Vittorio; Todoerti, Katia; La Rocca, Francesco; Caivano, Antonella; Trino, Stefania; Lionetti, Marta; Agnelli, Luca; De Luca, Luciana; Laurenzana, Ilaria; Neri, Antonino; Musto, Pellegrino

    2015-07-30

    Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM) which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, added to the pharmacogenetic profile of new and old agents in the analysis of efficacy and safety, could contribute to help clinical decisions move toward a precision medicine and a better clinical outcome for these patients. In this review, we describe the available literature concerning the genomic characterization and pharmacogenetics of plasma cell leukemia (PCL).

  20. Kinetic Trajectory Simulation (KTS) approach for one-dimensional, collisionless bounded plasmas

    International Nuclear Information System (INIS)

    A Kinetic Trajectory Simulation (KTS) model of a one-dimensional, time -independent, collisionless bounded plasma is presented, which can be used for modeling various situations of interest and yields results of high accuracy. Exact ion trajectories are followed, to calculate along them the ion distribution function, assuming an arbitrary injection ion distribution. The electrons, on the other hand, are assumed to have a half Maxwellian velocity distribution at injection so that their density can be calculated analytically. Starting from an initial guess, the potential profile is iterated towards the final time-independent self-consistent state. The method is exemplarily applied to a single-emitter diode and a one-dimensional plasma sheath. (author)

  1. Lagrangian Mapping Approach to Generate Intermittency and its Application in Plasma Turbulence

    Science.gov (United States)

    Subedi, P.; Matthaeus, W. H.; Tessein, J.; Chhiber, R.; Wan, M.

    2014-12-01

    The Minimal Lagrangian Mapping procedure developed in the context of neutral fluid turbulence(Rosales and Meneveau 2006) is a simple method to generate synthetic vector fields. Using a sequenceof low pass filtered fields, fluid particles are displaced at their rms-speed for some scale-dependenttime interval, and then interpolated back to a regular grid. Fields produced in this way are seen topossess certain properties of real turbulence. We extend the technique to plasmas by takinginto account the coupling between the velocity and magnetic fields. We examine several possibleapplications to plasma systems. One use is as initial conditions for simulations, wherein these syntheticfields may efficiently produce a strongly intermittent cascade. The intermittency properties of thesynthetic fields are also compared with those of the solar wind. Finally, studies of cosmic ray transportand modulation in the test particle approximation may benefit from improved realism in syntheticfields produced in this way.

  2. Molecular Classification and Pharmacogenetics of Primary Plasma Cell Leukemia: An Initial Approach toward Precision Medicine

    Directory of Open Access Journals (Sweden)

    Vittorio Simeon

    2015-07-01

    Full Text Available Primary plasma cell leukemia (pPCL is a rare and aggressive variant of multiple myeloma (MM which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, added to the pharmacogenetic profile of new and old agents in the analysis of efficacy and safety, could contribute to help clinical decisions move toward a precision medicine and a better clinical outcome for these patients. In this review, we describe the available literature concerning the genomic characterization and pharmacogenetics of plasma cell leukemia (PCL.

  3. Molecular Classification and Pharmacogenetics of Primary Plasma Cell Leukemia: An Initial Approach toward Precision Medicine.

    Science.gov (United States)

    Simeon, Vittorio; Todoerti, Katia; La Rocca, Francesco; Caivano, Antonella; Trino, Stefania; Lionetti, Marta; Agnelli, Luca; De Luca, Luciana; Laurenzana, Ilaria; Neri, Antonino; Musto, Pellegrino

    2015-01-01

    Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM) which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, added to the pharmacogenetic profile of new and old agents in the analysis of efficacy and safety, could contribute to help clinical decisions move toward a precision medicine and a better clinical outcome for these patients. In this review, we describe the available literature concerning the genomic characterization and pharmacogenetics of plasma cell leukemia (PCL). PMID:26263974

  4. Molecular Classification and Pharmacogenetics of Primary Plasma Cell Leukemia: An Initial Approach toward Precision Medicine

    Science.gov (United States)

    Simeon, Vittorio; Todoerti, Katia; La Rocca, Francesco; Caivano, Antonella; Trino, Stefania; Lionetti, Marta; Agnelli, Luca; De Luca, Luciana; Laurenzana, Ilaria; Neri, Antonino; Musto, Pellegrino

    2015-01-01

    Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM) which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, added to the pharmacogenetic profile of new and old agents in the analysis of efficacy and safety, could contribute to help clinical decisions move toward a precision medicine and a better clinical outcome for these patients. In this review, we describe the available literature concerning the genomic characterization and pharmacogenetics of plasma cell leukemia (PCL). PMID:26263974

  5. Master Sintering Surface: A practical approach to its construction and utilization for Spark Plasma Sintering prediction

    Directory of Open Access Journals (Sweden)

    Pouchly V.

    2012-01-01

    Full Text Available The sintering is a complex thermally activated process, thus any prediction of sintering behaviour is very welcome not only for industrial purposes. Presented paper shows the possibility of densification prediction based on concept of Master Sintering Surface (MSS for pressure assisted Spark Plasma Sintering (SPS. User friendly software for evaluation of the MSS is presented. The concept was used for densification prediction of alumina ceramics sintered by SPS.

  6. Molecular classification and pharmacogenetics of primary plasma cell leukemia: an initial approach toward precision medicine

    OpenAIRE

    Vittorio Simeon; Katia Todoerti; Francesco La Rocca; Antonella Caivano; Stefania Trino; Marta Lionetti; Luca Agnelli; Luciana De Luca; Ilaria Laurenzana; Antonino Neri; Pellegrino Musto

    2015-01-01

    Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM) which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, ...

  7. Multi-fluid approach to high-frequency waves in plasmas: I. Small-amplitude regime in fully ionized medium

    CERN Document Server

    Martínez-Gómez, David; Terradas, Jaume

    2016-01-01

    Ideal MHD provides an accurate description of low-frequency Alfv\\'en waves in fully ionized plasmas. However, higher frequency waves in many plasmas of the solar atmosphere cannot be correctly described by ideal MHD and a more accurate model is required. Here, we study the properties of small-amplitude incompressible perturbations in both the low and the high frequency ranges in plasmas composed of several ionized species. We use a multi-fluid approach and take into account the effects of collisions between ions and the inclusion of Hall's term in the induction equation. Through the analysis of the corresponding dispersion relations and numerical simulations we check that at high frequencies ions of different species are not as strongly coupled as in the low frequency limit. Hence, they cannot be treated as a single fluid. In addition, elastic collisions between the distinct ionized species are not negligible for high frequency waves since an appreciable damping is obtained. Furthermore, Coulomb collisions be...

  8. Contemporary particle-in-cell approach to laser-plasma modelling

    Science.gov (United States)

    Arber, T. D.; Bennett, K.; Brady, C. S.; Lawrence-Douglas, A.; Ramsay, M. G.; Sircombe, N. J.; Gillies, P.; Evans, R. G.; Schmitz, H.; Bell, A. R.; Ridgers, C. P.

    2015-11-01

    Particle-in-cell (PIC) methods have a long history in the study of laser-plasma interactions. Early electromagnetic codes used the Yee staggered grid for field variables combined with a leapfrog EM-field update and the Boris algorithm for particle pushing. The general properties of such schemes are well documented. Modern PIC codes tend to add to these high-order shape functions for particles, Poisson preserving field updates, collisions, ionisation, a hybrid scheme for solid density and high-field QED effects. In addition to these physics packages, the increase in computing power now allows simulations with real mass ratios, full 3D dynamics and multi-speckle interaction. This paper presents a review of the core algorithms used in current laser-plasma specific PIC codes. Also reported are estimates of self-heating rates, convergence of collisional routines and test of ionisation models which are not readily available elsewhere. Having reviewed the status of PIC algorithms we present a summary of recent applications of such codes in laser-plasma physics, concentrating on SRS, short-pulse laser-solid interactions, fast-electron transport, and QED effects.

  9. Estimating ancestral distributions of lineages with uncertain sister groups: a statistical approach to Dispersal-Vicariance Analysis and a case using Aesculus L. (Sapindaceae) including fossils

    Institute of Scientific and Technical Information of China (English)

    A.J. HARRIS; Qiu-Yun (Jenny) XIANG

    2009-01-01

    We propose a simple statistical approach for using Dispersal-Vicariance Analysis (DIVA) software to infer biogeographic histories without fully bifurcating trees. In this approach, ancestral ranges are first optimized for a sample of Bayesian trees. The probability P of an ancestral range r at a node is then calculated as P(rY)= Σnt=1 F(rY)tPt where Y is a node, and F(rY) is the frequency of range r among all the optimal solutions resulting from DIVA optimization at node Y, t is one of n topologies optimized, and Pt is the probability of topology t. Node Y is a hypothesized ancestor shared by a specific crown lineage and the sister of that lineage "x", where x may vary due to phylogenetic uncertainty (polytomies and nodes with posterior probability <100%). Using this method, the ancestral distribution at Y can be estimated to provide inference of the geographic origins of the specific crown group of interest. This approach takes into account phylogenetic uncertainty as well as uncertainty from DIVA optimization. It is an extension of the previously described method called Bayes-DIVA, which pairs Bayesian phylogenetic analysis with biogeographic analysis using DIVA. Further, we show that the probability P of an ancestral range at Y calculated using this method does not equate to pp* F(rY) on the Bayesian consensus tree when both variables are < 100%, where pp is the posterior probability and F(rY) is the frequency of range r for the node containing the specific crown group. We tested our DIVA-Bayes approach using Aesculus L., which has major lineages unresolved as a polytomy. We inferred the most probable geographic origins of the five traditional sections of Aesculus and ofAesculus californica Nutt. and examined range subdivisions at parental nodes of these lineages.Additionally, we used the DIVA-Bayes data from Aesculus to quantify the effects on biogeographic inference of including two wildcard fossil taxa in phylogenetic analysis. Our analysis resolved the

  10. A multi-diagnostic approach to understanding high-latitude plasma transport during the Halloween 2003 storm

    Directory of Open Access Journals (Sweden)

    P. Yin

    2008-09-01

    Full Text Available During the Halloween 2003 storm event, significant electron density enhancements at elevated F-layer altitudes were recorded by the EISCAT and ESR radars in northern Europe between 20:00 and 24:00 UT on 30 October. At the same time, a sequence of optical images from Qaanaaq in northern Greenland captured a series of eastward-propagating polar cap patches. In this paper, an advanced 4-D tomographic method based on the assimilation of global GPS data, coupled to a predictive Kalman filtering technique, has been used to reveal the linkage between these ionospheric structures. The combination of the various data sources has clearly established the time history of this extreme event, in which high-density plasma was uplifted in the dayside ionosphere and convected anti-sunward across the polar cap to European high latitudes at an elevated F-layer. Using this multi instrument approach, we can differentiate between those density structures observed at the ESR which occurred as a result of cross-polar transport and those more likely to have been produced by in-situ soft particle precipitation, a distinction which is supported by the ESR and EISCAT data. The multi-diagnostic approach reported here has the potential significantly to extend our current understanding of high latitude plasma transport and the origin of electron density enhancements.

  11. The Role of Plasma Kallikrein-Kinin Pathway in the Development of Diabetic Retinopathy: Pathophysiology and Therapeutic Approaches.

    Science.gov (United States)

    Abdulaal, Marwan; Haddad, Nour Maya N; Sun, Jennifer K; Silva, Paolo S

    2016-01-01

    Diabetic retinal disease is characterized by a series of retinal microvascular changes and increases in retinal vascular permeability that lead to development of diabetic retinopathy (DR) and diabetic macular edema (DME), respectively. Current treatment strategies for DR and DME are mostly limited to vascular endothelial growth factor (VEGF) inhibitors and laser photocoagulation. These treatment modalities are not universally effective in all patients, and potential side effects persist in a significant portion of patients. The plasma kallikrein-kinin system (KKS) is one of the pathways that has been identified in the vitreous in proliferative DR and DME. Preclinical studies have shown that the activation of intraocular KKS induces retinal vascular permeability, vasodilation, and retinal thickening. Proteomic analysis from vitreous of eyes with DME has shown that KKS and VEGF pathways are potentially independent biologic pathways. Furthermore, proteins associated with DME in the vitreous were significantly more correlated with the KKS pathway compared to VEGF pathway. Preclinical experiments on diabetic animals showed that inhibition of KKS components was found to be an effective approach to decrease retinal vascular permeability. An initial phase I human trial of a novel plasma kallikrein inhibitor for the treatment of DME is currently ongoing to test the safety of this approach and serves as an initial step in the translation of basic science discovery into an innovative clinical intervention. PMID:26959125

  12. Plasma-polyplumbagin-modified microfiber probes: a functional material approach to monitoring vascular access line contamination.

    Science.gov (United States)

    Davis, James; Molina, María Teresa; Leach, Christopher P; Cardosi, Marco F

    2013-10-01

    Atmospheric plasma treated carbon fiber filaments (10 micrometer) were used as the base substrate in the design of a probe intended for use within intravascular access devices. The microfiber probe was further functionalized with a polyplumbagin layer through which the line pH could be determined voltammetrically and therein provide the potential for obtaining diagnostic information relating to bacterial colonization of the line. The redox processes attributed to the immobilized polymer are characterized and a methodology developed to enable the acquisition of a redox signal that is selective and sensitive to pH. The applicability of the composite probe was demonstrated through examining the direct response in whole blood.

  13. A new approach for sequencing virion genome of Chinese HIV-1 strains subtype B and BC from plasma

    Institute of Scientific and Technical Information of China (English)

    MENG Zhe-feng; ZHANG Xiao-yan; XIN Ruo-lei; XING Hui; HE Xiang; XU Jian-qing; SHAO Yi-ming

    2011-01-01

    Background Although it was widely accepted that full-length HIV genome sequences is important in studying virus genetic evolution and variation as well as developing vaccine candidate,to directly sequencing HIV-1 genome of virion RNA remains as a challenge worldwide.Up to date,no published genomic sequences from virion RNA are available for Chinese prevalent HIV-1 strains due to the absence of specialized protocol and appropriate lab equipments.In this study we developed a straightforward approach for amplifying and sequencing HIV virion RNA from plasma by modifying published protocols and further confirmed it is suitable to process Chinese samples.Methods The methods for viral RNA extraction and gene amplification was modified and optimized as could be widely used in most Chinese labs.Gene alignment of Chinese HIV-1 strains was employed for designing specialized primer sets for Thai-B and BC recombinant strains.Based on comprehensively consideration of high variable gene region and recombinant breakpoints in BC recombinant strains,a three-amplicon strategy (including 4.3-kb gag-pol,2.9-kb pol-env and 2.7-kb env-ne) was developed.In addition,one amplicon (9 kb near full-length genome) was also used in 32 samples with varied viral loads.All amplicons were directly sequenced by DNA automated sequencer.Results Twenty-five percent(8/32) amplification efficiency was achieved by the one-amplicon strategy and 65.6%(21/32) by three-amplicon strategy.For one amplicon strategy,none of complete near full-length genome sequences was obtained by DNA sequencing.For three-amplicon strategy,75% sequences were achieved in DNA sequencing.Amplification efficiency but not sequencing efficiency was closely associated with viral loads.Conclusion Three-amplicon strategy covering all encoding regions of HIV-1 is suitable for Thai-B and BC recombinant strains and could be potentially employed in less-well equipped Chinese labs.

  14. RAPID DETERMINATION OF ACTINIDES IN URINE BY INDUCTIVELY-COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY: A HYBRID APPROACH

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, S.; Jones, V.

    2009-05-27

    A new rapid separation method that allows separation and preconcentration of actinides in urine samples was developed for the measurement of longer lived actinides by inductively coupled plasma mass spectrometry (ICP-MS) and short-lived actinides by alpha spectrometry; a hybrid approach. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration, if required, is performed using a streamlined calcium phosphate precipitation. Similar technology has been applied to separate actinides prior to measurement by alpha spectrometry, but this new method has been developed with elution reagents now compatible with ICP-MS as well. Purified solutions are split between ICP-MS and alpha spectrometry so that long- and short-lived actinide isotopes can be measured successfully. The method allows for simultaneous extraction of 24 samples (including QC samples) in less than 3 h. Simultaneous sample preparation can offer significant time savings over sequential sample preparation. For example, sequential sample preparation of 24 samples taking just 15 min each requires 6 h to complete. The simplicity and speed of this new method makes it attractive for radiological emergency response. If preconcentration is applied, the method is applicable to larger sample aliquots for occupational exposures as well. The chemical recoveries are typically greater than 90%, in contrast to other reported methods using flow injection separation techniques for urine samples where plutonium yields were 70-80%. This method allows measurement of both long-lived and short-lived actinide isotopes. 239Pu, 242Pu, 237Np, 243Am, 234U, 235U and 238U were measured by ICP-MS, while 236Pu, 238Pu, 239Pu, 241Am, 243Am and 244Cm were measured by alpha spectrometry. The method can also be adapted so that the separation of uranium isotopes for assay is not required, if uranium assay by direct dilution of the urine sample is preferred instead

  15. Which percentile-based approach should be preferred for calculating normalized citation impact values? An empirical comparison of five approaches including a newly developed citation-rank approach (P100)

    NARCIS (Netherlands)

    L. Bornmann; L. Leydesdorff; J. Wang

    2013-01-01

    For comparisons of citation impacts across fields and over time, bibliometricians normalize the observed citation counts with reference to an expected citation value. Percentile-based approaches have been proposed as a non-parametric alternative to parametric central-tendency statistics. Percentiles

  16. Better Quality Control: Stochastic Approaches to Optimize Properties and Performance of Plasma-Sprayed Coatings

    Science.gov (United States)

    Heimann, Robert B.

    2010-06-01

    Statistical design of experiment (SDE) methodology applied to design and performance testing of plasma-sprayed coatings follows an evolutionary path, usually starting with classic multiparameter screening designs (Plackett-Burman), and progressing through factorial (Taguchi) to limited response surface designs (Box-Behnken). Modern designs of higher dimensionality, such as central composite and D-optimal designs, will provide results with higher predictive power. Complex theoretical models relying on evolutionary algorithms, and application of artificial neuronal networks (ANNs) and fuzzy logic control (FLC) allow estimating the behavior of the complex plasma spray environment through validation either by key experiments or first-principle calculations. In this review, paper general principles of SDE will be discussed and examples be given that underscore the different powers of prediction of individual statistical designs. Basic rules of ANN and FLC will be briefly touched on, and their potential for increased reliability of coating performance through stringent quality control measures assessed. Salient features will be reviewed of studies performed to optimize thermal coating properties and processes reported in the pertinent literature between 2000 and the present.

  17. Thickness measurement approach for plasma sprayed coatings using ultrasonic testing technique

    Institute of Scientific and Technical Information of China (English)

    LIN Li; LI Xi-meng; XU Zhi-hui; LEI Ming-kai

    2004-01-01

    The special ultrasonic testing system has been developed for thickness measurement of plasma sprayed coatings. The ultrasonic immersion method was used to obtain stable coupling condition and avoid other disadvantages of contact method. Spherical acoustic lens were designed to focus ultrasonic beam so as to improve beam directivity and concentrate ultrasonic energy. To increase testing precision and avoid mussy wave signals, moderate pulse width and frequency of the transducer has been selected. The displacement of transducer in X-Y-Z directions was precisely manipulated by step-controlled system to insure the accuracy of focus length and repetition of measurement. Optimized testing conditions (with the transducer of center frequency of 10 MHz and crystal diameter of 8 mm, focus length of 9.5 mm, diameter of focal column of 0. 1 mm and length of focal column of 0.27 mm) were selected to determine the thickness between 285 -414 μm of ZrO2 coatings plasma sprayed on the nickel based superalloy. The frequency interval of the periodic extremums in ultrasonic power spectra decreases with increasing coating thickness. The ultrasonic results accord with those of metallographical method.

  18. Numerical Approach of Interactions of Proton Beams and Dense Plasmas with Quantum-Hydrodynamic/Particle-in-Cell Model

    Science.gov (United States)

    Zhang, Ya; Li, Lian; Jiang, Wei; Yi, Lin

    2016-07-01

    A one dimensional quantum-hydrodynamic/particle-in-cell (QHD/PIC) model is used to study the interaction process of an intense proton beam (injection density of 1017 cm‑3) with a dense plasma (initial density of ~ 1021 cm‑3), with the PIC method for simulating the beam particle dynamics and the QHD model for considering the quantum effects including the quantum statistical and quantum diffraction effects. By means of the QHD theory, the wake electron density and wakefields are calculated, while the proton beam density is calculated by the PIC method and compared to hydrodynamic results to justify that the PIC method is a more suitable way to simulate the beam particle dynamics. The calculation results show that the incident continuous proton beam when propagating in the plasma generates electron perturbations as well as wakefields oscillations with negative valleys and positive peaks where the proton beams are repelled by the positive wakefields and accelerated by the negative wakefields. Moreover, the quantum correction obviously hinders the electron perturbations as well as the wakefields. Therefore, it is necessary to consider the quantum effects in the interaction of a proton beam with cold dense plasmas, such as in the metal films. supported by National Natural Science Foundation of China (Nos. 11405067, 11105057, 11275007)

  19. A plasma formulary for physics, technology, and astrophysics

    CERN Document Server

    Diver, Declan

    2011-01-01

    Plasma physics has matured rapidly as a discipline, and now touches on many different research areas, including manufacturing processes. This collection of fundamental formulae and definitions in plasma physics is vital to anyone with an interest in plasmas or ionized gases, whether in physics, astronomy or engineering.Both theorists and experimentalists will find this book useful, as it incorporates the latest results and findings.The text treats astrophysical plasmas, fusion plasmas, industrial plasmas and low temperature plasmas as aspects of the same discipline - a unique approach made pos

  20. Comparing bottom-up and top-down approaches at the landscape scale, including agricultural activities and water systems, at the Roskilde Fjord, Denmark

    Science.gov (United States)

    Lequy, Emeline; Ibrom, Andreas; Ambus, Per; Massad, Raia-Silvia; Markager, Stiig; Asmala, Eero; Garnier, Josette; Gabrielle, Benoit; Loubet, Benjamin

    2015-04-01

    The greenhouse gas nitrous oxide (N2O) mainly originates in direct emissions from agricultural soils due to microbial reactions stimulated by the use of nitrogen fertilisers. Indirect N2O emissions from water systems due to nitrogen leaching and deposition from crop fields range between 26 and 37% of direct agricultural emissions, indicating their potential importance and uncertainty (Reay et al. 2012). The study presented here couples a top-down approach with eddy covariance (EC) and a bottom-up approach using different models and measurements. A QCL sensor at 96-m height on a tall tower measures the emissions of N2O from 1100 ha of crop fields and from the south part of the Roskilde fjord, in a 5-km radius area around the tall tower at Roskilde, Denmark. The bottom-up approach includes ecosystem modelling with CERES-EGC for the crops and PaSIM for the grasslands, and the N2O fluxes from the Roskilde fjord are derived from N2O sea water concentration measurements. EC measurements are now available from July to December 2014, and indicate a magnitude of the emissions from the crop fields around 0.2 mg N2O-N m-2 day-1 (range -9 to 5) which is consistent with the CERES-EGC simulations and calculations using IPCC emission factors. N2O fluxes from the Roskilde fjord in May and July indicated quite constant N2O concentrations around 0.1 µg N L-1 despite variations of nitrate and ammonium in the fjord. The calculated fluxes from these concentrations and the tall tower measurements consistently ranged between -7 and 6 mg N2O-N m-2 day-1. The study site also contains a waste water treatment plant, whose direct emissions will be measured in early 2015 using a dynamic plume tracer dispersion method (Mønster et al. 2014). A refined source attribution methodology together with more measurements and simulations of the N2O fluxes from the different land uses in this study site will provide a clearer view of the dynamics and budgets of N2O at the regional scale. The

  1. Opacity of Hot and Dense Plasmas of a Mixture using an Average-Atom Approach

    Institute of Scientific and Technical Information of China (English)

    袁建民

    2002-01-01

    An average-atom model is proposed to calculate the opacities of hot and dense plasmas of a mixture. A self-consistent scheme is used to reach the requirements of the same temperature and chemical potential for all kinds ofatoms in the mixtures, the same electron density at the boundaries between the atoms, and the electrical neutralitywithin each atomic sphere. The orbital energies and wavefunctions for the bound electrons are calculated withthe Dirac-Slater equations. The occupation numbers at each orbital of each kind of atom are determined by theFermi-Dirac distribution with the same chemical potential for all kinds of atoms. As an example, the opacity ofthe mixture of Au and Cd is calculated at a few temperatures and densities.

  2. Thermodynamics of the Quark-Gluon Plasma within a T-matrix approach

    CERN Document Server

    Lacroix, Gwendolyn; Buisseret, Fabien

    2015-01-01

    The strongly-coupled phase of the quark-gluon plasma (QGP) is studied here by resorting to a $T$-matrix formulation in which the medium is seen as a non-ideal gas of quasiparticles (quarks, antiquarks and gluons) interacting nonpertubatively. In the temperature range under study, (1-5) $T_c$, where $T_c$ is the temperature of deconfinement, the interactions are expected to be strong enough to generate bound states. The dissociation temperature of such binary bound states is thus computed here. The more the quasiparticles involved in the binary system are heavy, the more the bound state is likely to survive significantly above $T_c$. Then, the QGP equations of state at zero and small baryonic potential are computed for $N_f = 2$ and $N_f = 2 + 1$ by resorting to the Dashen, Ma and Bernstein formulation of statistical mechanics. Comparisons with current lattice QCD data are presented.

  3. Reliability and Construct Validity of the Psychopathic Personality Inventory-Revised in a Swedish Non-Criminal Sample - A Multimethod Approach including Psychophysiological Correlates of Empathy for Pain.

    Directory of Open Access Journals (Sweden)

    Karolina Sörman

    Full Text Available Cross-cultural investigation of psychopathy measures is important for clarifying the nomological network surrounding the psychopathy construct. The Psychopathic Personality Inventory-Revised (PPI-R is one of the most extensively researched self-report measures of psychopathic traits in adults. To date however, it has been examined primarily in North American criminal or student samples. To address this gap in the literature, we examined PPI-R's reliability, construct validity and factor structure in non-criminal individuals (N = 227 in Sweden, using a multimethod approach including psychophysiological correlates of empathy for pain. PPI-R construct validity was investigated in subgroups of participants by exploring its degree of overlap with (i the Psychopathy Checklist: Screening Version (PCL:SV, (ii self-rated empathy and behavioral and physiological responses in an experiment on empathy for pain, and (iii additional self-report measures of alexithymia and trait anxiety. The PPI-R total score was significantly associated with PCL:SV total and factor scores. The PPI-R Coldheartedness scale demonstrated significant negative associations with all empathy subscales and with rated unpleasantness and skin conductance responses in the empathy experiment. The PPI-R higher order Self-Centered Impulsivity and Fearless Dominance dimensions were associated with trait anxiety in opposite directions (positively and negatively, respectively. Overall, the results demonstrated solid reliability (test-retest and internal consistency and promising but somewhat mixed construct validity for the Swedish translation of the PPI-R.

  4. Polyphasic Approach Including MALDI-TOF MS/MS Analysis for Identification and Characterisation of Fusarium verticillioides in Brazilian Corn Kernels

    Directory of Open Access Journals (Sweden)

    Susane Chang

    2016-02-01

    Full Text Available Fusarium verticillioides is considered one of the most important global sources of fumonisins contamination in food and feed. Corn is one of the main commodities produced in the Northeastern Region of Brazil. The present study investigated potential mycotoxigenic fungal strains belonging to the F. verticillioides species isolated from corn kernels in 3 different Regions of the Brazilian State of Pernambuco. A polyphasic approach including classical taxonomy, molecular biology, MALDI-TOF MS and MALDI-TOF MS/MS for the identification and characterisation of the F. verticillioides strains was used. Sixty F. verticillioides strains were isolated and successfully identified by classical morphology, proteomic profiles of MALDI-TOF MS, and by molecular biology using the species-specific primers VERT-1 and VERT-2. FUM1 gene was further detected for all the 60 F. verticillioides by using the primers VERTF-1 and VERTF-2 and through the amplification profiles of the ISSR regions using the primers (GTG5 and (GACA4. Results obtained from molecular analysis shown a low genetic variability among these isolates from the different geographical regions. All of the 60 F. verticillioides isolates assessed by MALDI-TOF MS/MS presented ion peaks with the molecular mass of the fumonisin B1 (721.83 g/mol and B2 (705.83 g/mol.

  5. Description of excited states in [Re(Imidazole)(CO)3 (Phen)](+) including solvent and spin-orbit coupling effects: Density functional theory versus multiconfigurational wavefunction approach.

    Science.gov (United States)

    Fumanal, Maria; Daniel, Chantal

    2016-10-15

    The low-lying electronic excited states of [Re(imidazole)(CO)3 (phen)](+) (phen = 1,10-phenanthroline) ranging between 420 nm and 330 nm have been calculated by means of relativistic spin-orbit time-dependent density functional theory (TD-DFT) and wavefunction approaches (state-average-CASSCF/CASPT2). A direct comparison between the theoretical absorption spectra obtained with different methods including SOC and solvent corrections for water points to the difficulties at describing on the same footing the bands generated by metal-to-ligand charge transfer (MLCT), intraligand (IL) transition, and ligand-to-Ligand- charge transfer (LLCT). While TD-DFT and three-roots-state-average CASSCF (10,10) reproduce rather well the lowest broad MLCT band observed in the experimental spectrum between 420 nm and 330 nm, more flexible wavefunctions enlarged either by the number of roots or by the number of active orbitals and electrons destabilize the MLCT states by introducing IL and LLCT character in the lowest part of the absorption spectrum. © 2016 Wiley Periodicals, Inc.

  6. Comparative efficacy and safety of the left versus right radial approach for percutaneous coronary procedures: a meta-analysis including 6870 patients.

    Science.gov (United States)

    Xia, S L; Zhang, X B; Zhou, J S; Gao, X

    2015-08-01

    The radial approach is widely used in the treatment of patients with coronary artery disease. We conducted a meta-analysis of published results on the efficacy and safety of the left and right radial approaches in patients undergoing percutaneous coronary procedures. A systematic search of reference databases was conducted, and data from 14 randomized controlled trials involving 6870 participants were analyzed. The left radial approach was associated with significant reductions in fluoroscopy time [standardized mean difference (SMD)=-0.14, 95% confidence interval (CI)=-0.19 to -0.09; Pright radial approaches [risk ratios (RR)=0.98; 95%CI=0.77-1.25; P=0.88] or procedural time (SMD=-0.05, 95%CI=0.17-0.06; P=0.38). Tortuosity of the subclavian artery (RR=0.27, 95%CI=0.14-0.50; Pright radial approach. A greater number of catheters were used with the left than with the right radial approach (SMD=0.25, 95%CI=0.04-0.46; P=0.02). We conclude that the left radial approach is as safe as the right radial approach, and that the left radial approach should be recommended for use in percutaneous coronary procedures, especially in percutaneous coronary angiograms.

  7. Analysis of the low-pressure plasma pretreated polymer surface in terms of acid-base approach

    Science.gov (United States)

    Kraus, Eduard; Orf, Lukas; Baudrit, Benjamin; Heidemeyer, Peter; Bastian, Martin; Bonenberger, Ramona; Starostina, Irina; Stoyanov, Oleg

    2016-05-01

    We demonstrate the use of a modern wetting method for determining the acid-base properties of treated polymer surfaces for different plastics and adhesives. The effect of the surface treatment with low pressure plasma was evaluated from the viewpoint of acid-base approach with plastics polyoxymethylene (POM) and polyetheretherketone (PEEK). The correlations between the acid-base properties and the identified mechanical tensile strengths of adhesive bonded joints were evaluated and discussed. In the investigated range the determination coefficients for POM and PEEK were calculated to R2 = 0.93 and R2 = 0.97, respectively. These relatively high determination coefficients showed a good correlation between the mechanical strength and the acidity parameter ΔDshort for use in bonding technology for surface pretreatment of polymers with LPP.

  8. A modeling approach for heat conduction and radiation diffusion in plasma-photon mixture in temperature nonequilibrium

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-09

    We present a simple approach for determining ion, electron, and radiation temperatures of heterogeneous plasma-photon mixtures, in which temperatures depend on both material type and morphology of the mixture. The solution technique is composed of solving ion, electron, and radiation energy equations for both mixed and pure phases of each material in zones containing random mixture and solving pure material energy equations in subdivided zones using interface reconstruction. Application of interface reconstruction is determined by the material configuration in the surrounding zones. In subdivided zones, subzonal inter-material energy exchanges are calculated by heat fluxes across the material interfaces. Inter-material energy exchange in zones with random mixtures is modeled using the length scale and contact surface area models. In those zones, inter-zonal heat flux in each material is determined using the volume fractions.

  9. A modeling approach for heat conduction and radiation di usion in plasma-photon mixture in temperature nonequilibrium

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-09

    We present a simple approach for determining ion, electron, and radiation temperatures of heterogeneous plasma-photon mixtures, in which temperatures depend on both material type and morphology of the mixture. The solution technique is composed of solving ion, electron, and radiation energy equations for both mixed and pure phases of each material in zones containing random mixture and solving pure material energy equations in subdivided zones using interface reconstruction. Application of interface reconstruction is determined by the material configuration in the surrounding zones. In subdivided zones, subzonal inter-material energy exchanges are calculated by heat fluxes across the material interfaces. Inter-material energy exchange in zones with random mixtures is modeled using the length scale and contact surface area models. In those zones, inter-zonal heat flux in each material is determined using the volume fractions.

  10. A NEW COSMIC RAY TRANSPORT THEORY IN PARTIALLY TURBULENT SPACE PLASMAS: EXTENDING THE QUASILINEAR APPROACH

    International Nuclear Information System (INIS)

    A new transport theory of cosmic rays in magnetized space plasmas with axisymmetric incompressible magnetic turbulence is developed extending the quasilinear approximation to the particle orbit. Arbitrary gyrophase deviations from the unperturbed spiral orbits in the uniform magnetic field are allowed. For quasi-stationary and spatially homogeneous magnetic turbulence, we derive the small Larmor radius approximation gyrophase-averaged cosmic ray Fokker-Planck coefficients. The generalized Fokker-Planck coefficients correctly reduce to their known quasilinear values in the corresponding limit. New forms of the quasilinear Fokker-Planck coefficients in axisymmetric turbulence are derived which no longer involve infinite sums of products of Bessel functions, which facilitate their numerical computation for specified turbulence field correlation tensors. The Fokker-Planck coefficients for arbitrary phase orbits of the cosmic ray particles provide strict upper limits for the perpendicular and pitch-angle Fokker-Planck coefficients, which in turn yield strict upper and lower limits for the perpendicular and parallel spatial diffusion coefficients, respectively, describing the spatial diffusion of the isotropic part of the cosmic ray phase space density. For the associated mean free paths, we find for this general case that the product of the minimum parallel mean free path with the sum of the maximum perpendicular mean free paths equals R2L, where RL denotes the cosmic ray gyroradius.

  11. Comparative efficacy and safety of the left versus right radial approach for percutaneous coronary procedures: a meta-analysis including 6870 patients

    Directory of Open Access Journals (Sweden)

    S.L. Xia

    2015-08-01

    Full Text Available The radial approach is widely used in the treatment of patients with coronary artery disease. We conducted a meta-analysis of published results on the efficacy and safety of the left and right radial approaches in patients undergoing percutaneous coronary procedures. A systematic search of reference databases was conducted, and data from 14 randomized controlled trials involving 6870 participants were analyzed. The left radial approach was associated with significant reductions in fluoroscopy time [standardized mean difference (SMD=-0.14, 95% confidence interval (CI=-0.19 to -0.09; P<0.00001] and contrast volume (SMD=-0.07, 95%CI=-0.12 to -0.02; P=0.009. There were no significant differences in rate of procedural failure of the left and the right radial approaches [risk ratios (RR=0.98; 95%CI=0.77-1.25; P=0.88] or procedural time (SMD=-0.05, 95%CI=0.17-0.06; P=0.38. Tortuosity of the subclavian artery (RR=0.27, 95%CI=0.14-0.50; P<0.0001 was reported more frequently with the right radial approach. A greater number of catheters were used with the left than with the right radial approach (SMD=0.25, 95%CI=0.04-0.46; P=0.02. We conclude that the left radial approach is as safe as the right radial approach, and that the left radial approach should be recommended for use in percutaneous coronary procedures, especially in percutaneous coronary angiograms.

  12. Practical diagnostic approaches to composite plasma cell neoplasm and low grade B-cell lymphoma/clonal infiltrates in the bone marrow.

    Science.gov (United States)

    Hussein, Shafinaz; Gill, Kamraan; Baer, Lea N; Hoehn, Daniela; Mansukhani, Mahesh; Jobanputra, Vaidehi; Bhagat, Govind; Alobeid, Bachir

    2015-03-01

    Composite plasma cell neoplasm (PCN) and low grade B-cell lymphoma (B-NHL) in the bone marrow are uncommon and raise the differential diagnosis of B-NHL with plasmacytic differentiation and PCN with lymphoplasmacytic morphology. This can be a challenging differential diagnosis, and the distinctions are important because of differences in management. We report five cases of composite PCN with B-NHL or clonal B-cell infiltrates involving the bone marrow. By using multiple different diagnostic modalities, including immunophenotyping by flow cytometry and immunohistochemistry, cytogenetic analysis and IGH gene rearrangement studies by polymerase chain reaction, we were able to distinguish two distinct clonally unrelated neoplasms in all cases. We describe the utility and pitfalls of these different diagnostic modalities. Flow cytometric analysis with a panel of antibodies that includes CD19, CD56, CD138, CD45 and other aberrant markers commonly expressed by PCN will allow identification of clonally unrelated PCN and B-NHL in a composite neoplasm, and distinguish them from B-NHL with plasmacytic differentiation and PCN with lymphoplasmacytic morphology. Cytogenetic and molecular analyses can give false-negative or false-positive results. In summary, a multimodal approach utilizing these different tools, including clinical data, should be used to arrive at the correct diagnosis.

  13. Complex plasmas scientific challenges and technological opportunities

    CERN Document Server

    Lopez, Jose; Becker, Kurt; Thomsen, Hauke

    2014-01-01

    This book provides the reader with an introduction to the physics of complex plasmas, a discussion of the specific scientific and technical challenges they present, and an overview of their potential technological applications. Complex plasmas differ from conventional high-temperature plasmas in several ways: they may contain additional species, including nanometer- to micrometer-sized particles, negative ions, molecules and radicals, and they may exhibit strong correlations or quantum effects. This book introduces the classical and quantum mechanical approaches used to describe and simulate complex plasmas. It also covers some key experimental techniques used in the analysis of these plasmas, including calorimetric probe methods, IR absorption techniques and X-ray absorption spectroscopy. The final part of the book reviews the emerging applications of microcavity and microchannel plasmas, the synthesis and assembly of nanomaterials through plasma electrochemistry, the large-scale generation of ozone using mi...

  14. Approaching Defect-free Amorphous Silicon Nitride by Plasma-assisted Atomic Beam Deposition for High Performance Gate Dielectric.

    Science.gov (United States)

    Tsai, Shu-Ju; Wang, Chiang-Lun; Lee, Hung-Chun; Lin, Chun-Yeh; Chen, Jhih-Wei; Shiu, Hong-Wei; Chang, Lo-Yueh; Hsueh, Han-Ting; Chen, Hung-Ying; Tsai, Jyun-Yu; Lu, Ying-Hsin; Chang, Ting-Chang; Tu, Li-Wei; Teng, Hsisheng; Chen, Yi-Chun; Chen, Chia-Hao; Wu, Chung-Lin

    2016-01-01

    In the past few decades, gate insulators with a high dielectric constant (high-k dielectric) enabling a physically thick but dielectrically thin insulating layer, have been used to replace traditional SiOx insulator and to ensure continuous downscaling of Si-based transistor technology. However, due to the non-silicon derivative natures of the high-k metal oxides, transport properties in these dielectrics are still limited by various structural defects on the hetero-interfaces and inside the dielectrics. Here, we show that another insulating silicon compound, amorphous silicon nitride (a-Si3N4), is a promising candidate of effective electrical insulator for use as a high-k dielectric. We have examined a-Si3N4 deposited using the plasma-assisted atomic beam deposition (PA-ABD) technique in an ultra-high vacuum (UHV) environment and demonstrated the absence of defect-related luminescence; it was also found that the electronic structure across the a-Si3N4/Si heterojunction approaches the intrinsic limit, which exhibits large band gap energy and valence band offset. We demonstrate that charge transport properties in the metal/a-Si3N4/Si (MNS) structures approach defect-free limits with a large breakdown field and a low leakage current. Using PA-ABD, our results suggest a general strategy to markedly improve the performance of gate dielectric using a nearly defect-free insulator. PMID:27325155

  15. Dip Coating of Nano Hydroxyapatite on Titanium Alloy with Plasma Assisted γ-Alumina Buffer Layer: A Novel Coating Approach

    Institute of Scientific and Technical Information of China (English)

    M.Khalid; M.Mujahid; A.Nusair Khan; R.S.Rawat

    2013-01-01

    This paper reported a novel coating approach to deposit a thin,crack free and nano-structured hydroxyapatite (HA) film on Ti6Al4V alloy with Al2O3 buffer layer for biomedical implants.The Al2O3 buffer layer was deposited by plasma spraying while the HA top layer was applied by dip coating technique.The X-ray diffraction (XRD) and Raman reflections of alumina buffer layer showed α-to γ-Al2O3 phase transformation;and the fractographic analysis of the sample revealed the formation of columnar grains in well melted splats.The bonding strength between Al2O3 coating and Ti6Al4V substrate was estimated to be about 40 MPa.The presence of dip coated HA layer was confirmed using XRD,scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analysis.The SEM images exhibited that HA top layer enveloped homogenously the troughs and crests of the underneath rough (Ra =2.91 μm) Al2O3 surface.It is believed that the novel coating approach adopted might render the implant suitable for rapid cement-less fixation as well as biocompatible for longer periods.

  16. Approaching Defect-free Amorphous Silicon Nitride by Plasma-assisted Atomic Beam Deposition for High Performance Gate Dielectric

    Science.gov (United States)

    Tsai, Shu-Ju; Wang, Chiang-Lun; Lee, Hung-Chun; Lin, Chun-Yeh; Chen, Jhih-Wei; Shiu, Hong-Wei; Chang, Lo-Yueh; Hsueh, Han-Ting; Chen, Hung-Ying; Tsai, Jyun-Yu; Lu, Ying-Hsin; Chang, Ting-Chang; Tu, Li-Wei; Teng, Hsisheng; Chen, Yi-Chun; Chen, Chia-Hao; Wu, Chung-Lin

    2016-06-01

    In the past few decades, gate insulators with a high dielectric constant (high-k dielectric) enabling a physically thick but dielectrically thin insulating layer, have been used to replace traditional SiOx insulator and to ensure continuous downscaling of Si-based transistor technology. However, due to the non-silicon derivative natures of the high-k metal oxides, transport properties in these dielectrics are still limited by various structural defects on the hetero-interfaces and inside the dielectrics. Here, we show that another insulating silicon compound, amorphous silicon nitride (a-Si3N4), is a promising candidate of effective electrical insulator for use as a high-k dielectric. We have examined a-Si3N4 deposited using the plasma-assisted atomic beam deposition (PA-ABD) technique in an ultra-high vacuum (UHV) environment and demonstrated the absence of defect-related luminescence; it was also found that the electronic structure across the a-Si3N4/Si heterojunction approaches the intrinsic limit, which exhibits large band gap energy and valence band offset. We demonstrate that charge transport properties in the metal/a-Si3N4/Si (MNS) structures approach defect-free limits with a large breakdown field and a low leakage current. Using PA-ABD, our results suggest a general strategy to markedly improve the performance of gate dielectric using a nearly defect-free insulator.

  17. Kubo-Greenwood approach to conductivity in dense plasmas with average atom models

    CERN Document Server

    Starrett, C E

    2016-01-01

    A new formulation of the Kubo-Greenwood conductivity for average atom models is given. The new formulation improves upon previous by explicitly including the ionic-structure factor. Calculations based on this new expression lead to much improved agreement with ab initio results for DC conductivity of warm dense hydrogen and beryllium, and for thermal conductivity of hydrogen. We also give and test a slightly modified Ziman-Evans formula for the resistivity that includes a non-free electron density of states, thus removing an ambiguity in the original Ziman-Evans formula. Again results based on this expression are in good agreement with ab initio simulations for warm dense beryllium and hydrogen. However, for both these expressions, calculations of the electrical conductivity of warm dense aluminum lead to poor agreement at low temperatures compared to ab initio simulations.

  18. International school of plasma physics course on instabilities and confinement in toroidal plasmas. Varenna (Italy), September 27-October 9, 1971

    International Nuclear Information System (INIS)

    The lectures of a Varenna Summer School about the theme Instabilities and Confinement in toroidal Plasmas are given. The topics included are: high-beta toroidal pinches, non-MHD instabilities and anomalous transport, analogy between turbulent transfer in velocity space and plasma collisioned transport in real space, the magnetohydrodynamic approach of plasma confinement in closed magnetic configurations, properties of isodynamical equilibrium configurations and their generalization, transport theory for toroidal plasmas, plasma physics, low-β toroidal machines, the neoclassical theory of transit time magnetic pumping, radio frequency heating of toroidal plasmas, plasma heating at lower hybrid frequency, RF-plasma heating with L-structures, numerical simulation, dynamical stabilization of low frequency waves in inhomogeneous plasmas, dynamic and feedback stabilization of plasmas and problems with nuclear fusion reactors

  19. Numerical study of chiral plasma instability within the classical statistical field theory approach

    Science.gov (United States)

    Buividovich, P. V.; Ulybyshev, M. V.

    2016-07-01

    We report on a numerical study of real-time dynamics of electromagnetically interacting chirally imbalanced lattice Dirac fermions within the classical statistical field theory approach. Namely, we perform exact simulations of the real-time quantum evolution of fermionic fields coupled to classical electromagnetic fields, which are in turn coupled to the vacuum expectation value of the fermionic electric current. We use Wilson-Dirac Hamiltonian for fermions, and noncompact action for the gauge field. In general, we observe that the backreaction of fermions on the electromagnetic field prevents the system from acquiring chirality imbalance. In the case of chirality pumping in parallel electric and magnetic fields, the electric field is screened by the produced on-shell fermions and the accumulation of chirality is hence stopped. In the case of evolution with initially present chirality imbalance, axial charge tends to transform to helicity of the electromagnetic field. By performing simulations on large lattices we show that in most cases this decay process is accompanied by the inverse cascade phenomenon, which transfers energy from short-wavelength to long-wavelength electromagnetic fields. In some simulations, however, we observe a very clear signature of inverse cascade for the helical magnetic fields that is not accompanied by the axial charge decay. This suggests that the relation between the inverse cascade and axial charge decay is not as straightforward as predicted by the simplest form of anomalous Maxwell equations.

  20. A dynamical quasiparticle approach for the Quark-Gluon-Plasma bulk and transport properties

    CERN Document Server

    Berrehrah, Hamza; Steinert, Thorsten; Cassing, Wolfgang

    2016-01-01

    The properties of quantum-chromo dynamics (QCD) nowadays are accessable by lattice QCD calculations at vanishing quark chemical potential $\\mu_q$=0 but often lack a transparent physical interpretation. In this review we report about results from an extended dynamical quasiparticle model (DQPM$^*$) in which the effective parton propagators have a complex selfenergy that depends on the temperature $T$ of the medium as well as on the chemical potential $\\mu_q$ and the parton three-momentum ${\\boldsymbol p}$ with respect to the medium at rest. It is demonstrated that this approach allows for a good description of QCD thermodynamics with respect to the entropy density, pressure etc. above the critical temperature $T_c \\approx$ 158 MeV. Furthermore, the quark susceptibility $\\chi_q$ and the quark number density $n_q$ are found to be reproduced simultaneously at zero and finite quark chemical potential. The shear and bulk viscosities $\\eta, \\zeta$, and the electric conductivity $\\sigma_e$ from the DQPM$^*$ also turn...

  1. Signal transduction profile of chemical sensitisers in dendritic cells: an endpoint to be included in a cell-based in vitro alternative approach to hazard identification?

    OpenAIRE

    Neves, BM; Gonçalo, Margarida; Figueiredo, A.; Duarte, CB; Lopes, MC; Cruz, MT

    2011-01-01

    The development of non-animal testing methods for the assessment of skin sensitisation potential is an urgent challenge within the framework of existing and forthcoming legislation. Efforts have been made to replace current animal tests, but so far no alternative methods have been developed. It is widely recognised that alternatives to animal testing cannot be accomplished with a single approach, but rather will require the integration of results obtained from different in vitro and in silico...

  2. Brine migration resulting from CO2 injection into saline aquifers – An approach to risk estimation including various levels of uncertainty

    DEFF Research Database (Denmark)

    Walter, Lena; Binning, Philip John; Oladyshkin, Sergey;

    2012-01-01

    resulting from displaced brine. Quantifying risk on the basis of numerical simulations requires consideration of different kinds of uncertainties and this study considers both, scenario uncertainty and statistical uncertainty. Addressing scenario uncertainty involves expert opinion on relevant geological...... features such as caprock properties, faults, and distinct geological layers. This is considered in this work by 6 different scenarios having different characteristic geological features. On the other hand, Monte Carlo methods are a classical approach to address statistical uncertainty. This is not feasible...

  3. A Focused Transport Approach to SEP acceleration at a Fast Parallel Shock in the Corona Including Self-excitation of Alfvén Waves

    Science.gov (United States)

    le Roux, J. A.

    2012-12-01

    It has been argued that the acceleration of SEPS at a quasi-parallel CME-driven shock to GeV energies in the corona only occurs if strong wave-excitation by SEPs ahead of the shock reduces the parallel mean free path upstream, thus boosting the rate of diffusive shock acceleration. To investigate this issue, we modeled SEP acceleration at a fast parallel traveling shock in the corona with an existing time-dependent focused transport model. The model has been expanded recently to also feature time-dependent self-excitation and damping of Alfvén waves by SEP anisotropies ahead of the shock based on standard quasi-linear theory. Alfvén wave propagation near the traveling shock is modeled based on standard theory for wave transport in a slowly varying non-uniform plasma medium. Preliminary results will be shown to illustrate the increase in wave power driven by SEP anisotropies upstream, the effect of the shock wave in shortening the wave length and increasing the wave amplitude of Alfvén waves, and the associated acceleration of SEPs by 1st order Fermi acceleration to high energies. The role of the acceleration of the cross-shock solar wind flow, which was found to create a downstream population of shock pre-heated particles which forms an additional source for injection into 1st order Fermi acceleration, will be discussed in terms of how it affects self-excitation of Alfvén waves and the formation of high-energy SEPs by 1st order Fermi acceleration.

  4. An Analytical APproach to the Turbulence—Relaxed State in Tokamak Plasmas

    Institute of Scientific and Technical Information of China (English)

    PENGXiao-Dong; QIUXiao-Ming

    2002-01-01

    Starting from the continuity,temperature,and motion equations of the trapped electron fluid in general tokamak magnetic field with positive or reversed shear and the definition of Lagrangian invariant,dL/dt=(δt=u.Δ↓)L=0,where u is convective velocity,the trapped electron dynamics is considered in the following two assumptions;(i)the turbulence is low frequency electrostatic,and (ii)L is a functional only of the density n,temperature T,and magnetic turbulence is low frequency electrostatic,and (ii) L is a functional only of the density n,temperature T,and magnetic field B,and the effect of perturbation potential φ is included in the convertive velocity u,i.e.,u,is a functional of n,T,B,and φ.The Lagrangian invariant hidden in the trapped elkectron dynamics is strictly found:L=in[(n/B)c1(T.B2/3)c2],where c1 and c2 are dimensionalee changeable parameters and c1 C2,From this Lagrangian invariant the turbulent particle and electron thermal transport scaling laws are derived:(n)ψq(ψ)=const.and ψq(ψ)=const.,which,in the liomit of large aspect ratio.reduce to n (r)q(r)=const,and T3/2(r)q(r)=const.,respectively.The latter two Scaling laws are compared with existent experimental results,being in good agreement.

  5. An Analytical Approach to the Turbulence-Relaxed State in Tokamak Plasmas

    Institute of Scientific and Technical Information of China (English)

    PENG Xiao-Dong; QIU Xiao-Ming

    2002-01-01

    Starting from the continuity, temperature, and motion equations of the trapped electron fluid in generaltokamak magnetic field with positive or reversed shear and the definition of Lagrangian invariant, dL / dt = ( t +u. )L =0, where u is convective velocity, the trapped electron dynamics is considered in the following two assumptions: (i) theturbulence is low frequency electrostatic, and (ii) L is a functional only of the density n, temperature T, and magneticfield B, and the effect of perturbation potential φ is included in the convective velocity u, i.e., u is a functional of n,T, B, and φ. The Lagrangian invariant hidden in the trapped electron dynamics is strictly found: L= ln[(n/B)c1(T/B2/3)c2], where c1 and c2 are dimensionless changeable parameters and c1 ∝ c2. From this Lagrangian invariant thewhich, in the limit of large aspect ratio, reduce to n(r)q(r) = const. and T3/2(r)q(r) = const., respectively. The lattertwo scaling laws are compared with existent experimental results, being in good agreement.

  6. Approaches towards Steady-State Advanced Divertor Operations on EAST by Active Control of Plasma-Wall Interactions

    International Nuclear Information System (INIS)

    Full text: EAST will be one of the world's first magnetic confinement devices that must address Plasma- Wall Interaction (PWI) issues facing high power steady-state operations. EAST has recently significantly augmented its RF heating capabilities up to 10 MW, including LHCD and ICRH. It has also undertaken an extensive upgrade during the recent shutdown to replace the carbon tiles on the main chamber wall and divertor surface by the Mo tiles, except those near the strike points, allowing baking up to 250 deg C, with active water cooling. The divertor titles will further be upgraded to monoblock Tungsten, as to be used in ITER, to address PWI issues for ITER and DEMO. EAST demonstrated long pulse operation over 100 s, entirely driven by LHCD during the last experimental campaign. In order to achieve this, the following major means were applied to EAST to actively control PWI interactions: 1. Active divertor pumping using an in-vessel large capacity cryopump for facilitating density control. 2. Advanced wall conditioning with Lithium (Li) evaporation and real-time, in-situ Li powder injection for controlling neutral recycling. 3. Localized divertor gas puffing for reducing peak heat fluxes near the strike points. 4. Strike point sweeping to spread the heat loads on the divertor target plates. In addition, highly radiative impurity Ar was injected into the divertor to further reduce the peak divertor heat fluxes and mitigate the in-out divertor plasma asymmetries in EAST. Despite the injection of Ar, Zeff in the core plasma was little affected, suggesting strong divertor screening. Ar seeding has also been explored in the newly achieved H-modes in EAST, significantly increasing the frequency and decreasing the amplitude of ELMs, thus reducing the particle and heat loads on the divertor target plates. These first results are very promising, and will further be investigated in EAST for high power, long pulse operations. EAST has now just started a new experimental

  7. A contoured gap coaxial plasma gun with injected plasma armature

    International Nuclear Information System (INIS)

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 μg of plasma with density above 1017 cm-3 to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 μg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  8. A contoured gap coaxial plasma gun with injected plasma armature.

    Science.gov (United States)

    Witherspoon, F Douglas; Case, Andrew; Messer, Sarah J; Bomgardner, Richard; Phillips, Michael W; Brockington, Samuel; Elton, Raymond

    2009-08-01

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 microg of plasma with density above 10(17) cm(-3) to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 microg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  9. A contoured gap coaxial plasma gun with injected plasma armature

    Science.gov (United States)

    Witherspoon, F. Douglas; Case, Andrew; Messer, Sarah J.; Bomgardner, Richard; Phillips, Michael W.; Brockington, Samuel; Elton, Raymond

    2009-08-01

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 μg of plasma with density above 1017 cm-3 to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 μg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  10. Treatment outcome and prognostic factor analysis in transplant-eligible Chinese myeloma patients receiving bortezomib-based induction regimens including the staged approach, PAD or VTD

    Directory of Open Access Journals (Sweden)

    Chim Chor

    2012-06-01

    Full Text Available Abstract Background We have reported promising outcomes using a staged approach, in which bortezomib/thalidomide/dexamethasone was used only in 14 patients with suboptimal response to VAD (vincristine/adriamycin/dexamethasone before autologous stem cell transplantation (ASCT. Here we compared the outcomes of the staged approach with frontline PAD (bortezomib/doxorubicin/dexamethasone or VTD (bortezomib/thalidomide/dexamethasone induction, and analysed prognostic factors for outcome. Patients and methods Ninety-one transplant-eligible Chinese patients received three induction regimens prior to ASCT [staged approach (N = 25, PAD (N = 31, VTD (N = 35]. and received thalidomide maintenance for 2 years post-ASCT. Results 43 (47.3% patients had International Staging System (ISS III disease. By an intention-to-treat analysis, the overall CR/nCR rate were 37.4% post-induction, and 62.6% post-ASCT. Five-year overall (OS and event-free (EFS survivals were 66% and 45.1%. There was no difference of the post-induction CR/nCR rate, EFS or OS between patients induced by these three regimens. Moreover, ISS III disease did not affect CR/nCR rates. Multivariate analysis showed that ISS and post-ASCT CR/nCR impacted OS while ISS and post-induction CR/nCR impacted EFS. Conclusions These three induction regimens produced comparable and favorable outcomes in myeloma. The unfavorable outcome of ISS stage III persisted despite upfront/early use of bortezomib. CR/nCR predicted favorable survivals.

  11. A quantile regression approach can reveal the effect of fruit and vegetable consumption on plasma homocysteine levels.

    Directory of Open Access Journals (Sweden)

    Eliseu Verly-Jr

    Full Text Available A reduction in homocysteine concentration due to the use of supplemental folic acid is well recognized, although evidence of the same effect for natural folate sources, such as fruits and vegetables (FV, is lacking. The traditional statistical analysis approaches do not provide further information. As an alternative, quantile regression allows for the exploration of the effects of covariates through percentiles of the conditional distribution of the dependent variable.To investigate how the associations of FV intake with plasma total homocysteine (tHcy differ through percentiles in the distribution using quantile regression.A cross-sectional population-based survey was conducted among 499 residents of Sao Paulo City, Brazil. The participants provided food intake and fasting blood samples. Fruit and vegetable intake was predicted by adjusting for day-to-day variation using a proper measurement error model. We performed a quantile regression to verify the association between tHcy and the predicted FV intake. The predicted values of tHcy for each percentile model were calculated considering an increase of 200 g in the FV intake for each percentile.The results showed that tHcy was inversely associated with FV intake when assessed by linear regression whereas, the association was different when using quantile regression. The relationship with FV consumption was inverse and significant for almost all percentiles of tHcy. The coefficients increased as the percentile of tHcy increased. A simulated increase of 200 g in the FV intake could decrease the tHcy levels in the overall percentiles, but the higher percentiles of tHcy benefited more.This study confirms that the effect of FV intake on lowering the tHcy levels is dependent on the level of tHcy using an innovative statistical approach. From a public health point of view, encouraging people to increase FV intake would benefit people with high levels of tHcy.

  12. Damping of Alfven waves in solar partially ionized plasmas: effect of neutral helium in multi-fluid approach

    OpenAIRE

    Zaqarashvili, T. V.; Khodachenko, M. L.; Rucker, H.O.

    2011-01-01

    Chromospheric and prominence plasmas contain neutral atoms, which may change the plasma dynamics through collision with ions. Most of the atoms are neutral hydrogen, but a significant amount of neutral helium may also be present in the plasma with a particular temperature. Damping of MHD waves due to ion collision with neutral hydrogen is well studied, but the effects of neutral helium are largely unknown. We aim to study the effect of neutral helium in the damping of Alfven waves in solar pa...

  13. Signal transduction profile of chemical sensitisers in dendritic cells: An endpoint to be included in a cell-based in vitro alternative approach to hazard identification?

    International Nuclear Information System (INIS)

    The development of non-animal testing methods for the assessment of skin sensitisation potential is an urgent challenge within the framework of existing and forthcoming legislation. Efforts have been made to replace current animal tests, but so far no alternative methods have been developed. It is widely recognised that alternatives to animal testing cannot be accomplished with a single approach, but rather will require the integration of results obtained from different in vitro and in silico assays. The argument subjacent to the development of in vitro dendritic cell (DC)-based assays is that sensitiser-induced changes in the DC phenotype can be differentiated from those induced by irritants. This assumption is derived from the unique capacity of DC to convert environmental signals encountered at the skin into a receptor expression pattern (MHC class II molecules, co-stimulatory molecules, chemokine receptors) and a soluble mediator release profile that will stimulate T lymphocytes. Since signal transduction cascades precede changes in surface marker expression and cytokine/chemokine secretion, these phenotypic modifications are a consequence of a signal transduction profile that is specifically triggered by sensitisers and not by irritants. A limited number of studies have addressed this subject and the present review attempts to summarise and highlight all of the signalling pathways modulated by skin sensitisers and irritants. Furthermore, we conclude this review by focusing on the most promising strategies suitable for inclusion into a cell-based in vitro alternative approach to hazard identification.

  14. Plasma Sources for Medical Applications - A Comparison of Spot Like Plasmas and Large Area Plasmas

    Science.gov (United States)

    Weltmann, Klaus-Dieter

    2015-09-01

    Plasma applications in life science are currently emerging worldwide. Whereas today's commercially available plasma surgical technologies such as argon plasma coagulation (APC) or ablation are mainly based on lethal plasma effects on living systems, the newly emerging therapeutic applications will be based on selective, at least partially non-lethal, possibly stimulating plasma effects on living cells and tissue. Promising results could be obtained by different research groups worldwide revealing a huge potential for the application of low temperature atmospheric pressure plasma in fields such as tissue engineering, healing of chronic wounds, treatment of skin diseases, tumor treatment based on specific induction of apoptotic processes, inhibition of biofilm formation and direct action on biofilms or treatment of dental diseases. The development of suitable and reliable plasma sources for the different therapies requires an in-depth knowledge of their physics, chemistry and parameters. Therefore much basic research still needs to be conducted to minimize risk and to provide a scientific fundament for new plasma-based medical therapies. It is essential to perform a comprehensive assessment of physical and biological experiments to clarify minimum standards for plasma sources for applications in life science and for comparison of different sources. One result is the DIN-SPEC 91315, which is now open for further improvements. This contribution intends to give an overview on the status of commercial cold plasma sources as well as cold plasma sources still under development for medical use. It will discuss needs, prospects and approaches for the characterization of plasmas from different points of view. Regarding the manageability in everyday medical life, atmospheric pressure plasma jets (APPJ) and dielectric barrier discharges (DBD) are of special interest. A comprehensive risk-benefit assessment including the state of the art of commercial sources for medical use

  15. Estimation of Genetic Variance Components Including Mutation and Epistasis using Bayesian Approach in a Selection Experiment on Body Weight in Mice

    DEFF Research Database (Denmark)

    Widyas, Nuzul; Jensen, Just; Nielsen, Vivi Hunnicke

    selected downwards and three lines were kept as controls. Bayesian statistical methods are used to estimate the genetic variance components. Mixed model analysis is modified including mutation effect following the methods by Wray (1990). DIC was used to compare the model. Models including mutation effect...... have better fit compared to the model with only additive effect. Mutation as direct effect contributes 3.18% of the total phenotypic variance. While in the model with interactions between additive and mutation, it contributes 1.43% as direct effect and 1.36% as interaction effect of the total variance...

  16. Metal plasmas for the fabrication of nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2006-09-21

    A review is provided covering metal plasma production, theenergetic condensation of metal plasmas, and the formation ofnanostructures using such plasmas. Plasma production techniques includepulsed laser ablation, filtered cathodic arcs, and various forms ofionized physical vapor deposition, namely magnetron sputtering withionization of sputtered atoms in radio frequency discharges,self-sputtering, and high power impulse magnetron sputtering. Thediscussion of energetic condensation focuses on the control of kineticenergy by biasing and also includes considerations of the potentialenergy and the processes occurring at subplantation and implantation. Inthe final section on nanostructures, two different approaches arediscussed. In the top-down approach, the primary nanostructures arelithographically produced and metal plasma is used to coat or filltrenches and vias. Additionally, multilayers with nanosize periods(nanolaminates) can be produced. In the bottom-up approach, thermodynamicforces are used to fabricate nanocomposites and nanoporous materials bydecomposition and dealloying.

  17. Use of a multi-isotope and multi-tracer approach including organic matter isotopes for quantifying nutrient contributions from agricultural vs wastewater sources

    Science.gov (United States)

    Kendall, C.; Silva, S. R.; Young, M. B.

    2013-12-01

    While nutrient isotopes are a well-established tool for quantifying nutrients inputs from agricultural vs wastewater treatment plant (WWTP) sources, we have found that combining nutrient isotopes with the C, N, and S isotopic compositions of dissolved and particulate organic matter, as part of a comprehensive multi-isotope and multi-tracer approach, is a much more diagnostic approach. The main reasons why organic matter C-N-S isotopes are a useful adjunct to studies of nutrient sources and biogeochemical processes are that the dissolved and particulate organic matter associated with (1) different kinds of animals (e.g., humans vs cows) often have distinctive isotopic compositions reflecting the different diets of the animals, and (2) the different processes associated with the different land uses (e.g., in the WWTP or associated with different crop types) often result in significant differences in the isotopic compositions of the organics. The analysis of the δ34S of particulate organic matter (POM) and dissolved organic matter (DOM) has been found to be especially useful for distinguishing and quantifying water, nutrient, and organic contributions from different land uses in aquatic systems where much of the organic matter is aquatic in origin. In such environments, the bacteria and algae incorporate S from sulfate and sulfide that is isotopically labeled by the different processes associated with different land uses. We have found that there is ~35 permil range in δ34S of POM along the river-estuary continuum in the San Joaquin/Sacramento River basin, with low values associated with sulfate reduction in the upstream wetlands and high values associated with tidal inputs of marine water into the estuary. Furthermore, rice agriculture results in relatively low δ34S values whereas WWTP effluent in the Sacramento River produces distinctly higher values than upstream of the WWTP, presumably because SO2 is used to treat chlorinated effluent. The fish living

  18. The experimental charge-density approach in the evaluation of intermolecular interactions. Application of a new module of the XD programming package to several solids including a pentapeptide.

    Science.gov (United States)

    Abramov, Y A; Volkov, A; Wu, G; Coppens, P

    2000-11-01

    A new module interfaced to the XD programming package has been used in the evaluation of intermolecular interactions and lattice energies of the crystals of p-nitroaniline, L-asparagine monohydrate and the pentapeptide Boc-Gln-D-Iva-Hyp-Ala-Phol (Boc = butoxycarbonyl, Iva = isovaline = ethylalanine, Phol = phenylalaninol). The electrostatic interactions are evaluated with the atom-centered distributed multipoles from KRMM (kappa'-restricted multipole model) refinements, using the Buckingham expression for non-overlapping charge densities. Results for p-nitroaniline are compared with Hartree-Fock (HF), density functional (DFT) and Moller-Plesset (MP2) supermolecular calculations and with HF and DFT periodic calculations. The HF and DFT methods fail to predict the stability of the p-nitroaniline crystal but the results of the experimental charge-density approach (ECDA) are in good agreement with both MP2 interaction energies and the experimental lattice energy. ECDA results for L-asparagine monohydrate compare well with those from DFT supermolecular and periodic HF calculations. The disorder of the terminal group in the pentapeptide, which persists at the experimental temperature of 20 K, corresponds to an energy difference of only 0.35 kJ mol(-1), which is too small to be reproduced with current methods. PMID:11058845

  19. Habitability of Super-Earth Planets around Main-Sequence Stars including Red Giant Branch Evolution: Models based on the Integrated System Approach

    CERN Document Server

    Cuntz, M; Schroeder, K -P; Bounama, C; Franck, S

    2011-01-01

    In a previous study published in Astrobiology, we focused on the evolution of habitability of a 10 M_E super-Earth planet orbiting a star akin to the Sun. This study was based on a concept of planetary habitability in accordance to the integrated system approach that describes the photosynthetic biomass production taking into account a variety of climatological, biogeochemical, and geodynamical processes. In the present study, we pursue a significant augmentation of our previous work by considering stars with zero-age main sequence masses between 0.5 and 2.0 M_sun with special emphasis on models of 0.8, 0.9, 1.2 and 1.5 M_sun. Our models of habitability consider again geodynamical processes during the main-sequence stage of these stars as well as during their red giant branch evolution. Pertaining to the different types of stars, we identify so-called photosynthesis-sustaining habitable zones (pHZ) determined by the limits of biological productivity on the planetary surface. We obtain various sets of solution...

  20. Positive approach: Implications for the relation between number theory and geometry, including connection to Santilli mathematics, from Fibonacci reconstitution of natural numbers and of prime numbers

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, Stein E., E-mail: stein.johansen@svt.ntnu.no [Institute for Basic Research, Division of Physics, Palm Harbor, Florida, USA and Norwegian University of Science and Technology, Department of Social Anthropology, Trondheim (Norway)

    2014-12-10

    The paper recapitulates some key elements in previously published results concerning exact and complete reconstitution of the field of natural numbers, both as ordinal and as cardinal numbers, from systematic unfoldment of the Fibonacci algorithm. By this natural numbers emerge as Fibonacci 'atoms' and 'molecules' consistent with the notion of Zeckendorf sums. Here, the sub-set of prime numbers appears not as the primary numbers, but as an epistructure from a deeper Fibonacci constitution, and is thus targeted from a 'positive approach'. In the Fibonacci reconstitution of number theory natural numbers show a double geometrical aspect: partly as extension in space and partly as position in a successive structuring of space. More specifically, the natural numbers are shown to be distributed by a concise 5:3 code structured from the Fibonacci algorithm via Pascal's triangle. The paper discusses possible implications for the more general relation between number theory and geometry, as well as more specifically in relation to hadronic mathematics, initiated by R.M. Santilli, and also briefly to some other recent science linking number theory more directly to geometry and natural systems.

  1. Positive approach: Implications for the relation between number theory and geometry, including connection to Santilli mathematics, from Fibonacci reconstitution of natural numbers and of prime numbers

    International Nuclear Information System (INIS)

    The paper recapitulates some key elements in previously published results concerning exact and complete reconstitution of the field of natural numbers, both as ordinal and as cardinal numbers, from systematic unfoldment of the Fibonacci algorithm. By this natural numbers emerge as Fibonacci 'atoms' and 'molecules' consistent with the notion of Zeckendorf sums. Here, the sub-set of prime numbers appears not as the primary numbers, but as an epistructure from a deeper Fibonacci constitution, and is thus targeted from a 'positive approach'. In the Fibonacci reconstitution of number theory natural numbers show a double geometrical aspect: partly as extension in space and partly as position in a successive structuring of space. More specifically, the natural numbers are shown to be distributed by a concise 5:3 code structured from the Fibonacci algorithm via Pascal's triangle. The paper discusses possible implications for the more general relation between number theory and geometry, as well as more specifically in relation to hadronic mathematics, initiated by R.M. Santilli, and also briefly to some other recent science linking number theory more directly to geometry and natural systems

  2. Analysis of the impact of climate change on groundwater related hydrological fluxes: a multi-model approach including different downscaling methods

    Directory of Open Access Journals (Sweden)

    S. Stoll

    2011-01-01

    Full Text Available Climate change related modifications in the spatio-temporal distribution of precipitation and evapotranspiration will have an impact on groundwater resources. This study presents a modelling approach exploiting the advantages of integrated hydrological modelling and a broad climate model basis. We applied the integrated MIKE SHE model on a perialpine, small catchment in northern Switzerland near Zurich. To examine the impact of climate change we forced the hydrological model with data from eight GCM-RCM combinations showing systematic biases which are corrected by three different statistical downscaling methods, not only for precipitation but also for the variables that govern potential evapotranspiration. The downscaling methods are evaluated in a split sample test and the sensitivity of the downscaling procedure on the hydrological fluxes is analyzed. The RCMs resulted in very different projections of potential evapotranspiration and, especially, precipitation. All three downscaling methods reduced the differences between the predictions of the RCMs and all corrected predictions showed no future groundwater stress which can be related to an expected increase in precipitation during winter. It turned out that especially the timing of the precipitation and thus recharge is very important for the future development of the groundwater levels. However, the simulation experiments revealed the weaknesses of the downscaling methods which directly influence the predicted hydrological fluxes, and thus also the predicted groundwater levels. The downscaling process is identified as an important source of uncertainty in hydrological impact studies, which has to be accounted for. Therefore it is strongly recommended to test different downscaling methods by using verification data before applying them to climate model data.

  3. Novel CIC point mutations and an exon-spanning, homozygous deletion identified in oligodendroglial tumors by a comprehensive genomic approach including transcriptome sequencing.

    Directory of Open Access Journals (Sweden)

    Sophie Eisenreich

    Full Text Available Oligodendroglial tumors form a distinct subgroup of gliomas, characterized by a better response to treatment and prolonged overall survival. Most oligodendrogliomas and also some oligoastrocytomas are characterized by a unique and typical unbalanced translocation, der(1,19, resulting in a 1p/19q co-deletion. Candidate tumor suppressor genes targeted by these losses, CIC on 19q13.2 and FUBP1 on 1p31.1, were only recently discovered. We analyzed 17 oligodendrogliomas and oligoastrocytomas by applying a comprehensive approach consisting of RNA expression analysis, DNA sequencing of CIC, FUBP1, IDH1/2, and array CGH. We confirmed three different genetic subtypes in our samples: i the "oligodendroglial" subtype with 1p/19q co-deletion in twelve out of 17 tumors; ii the "astrocytic" subtype in three tumors; iii the "other" subtype in two tumors. All twelve tumors with the 1p/19q co-deletion carried the most common IDH1 R132H mutation. In seven of these tumors, we found protein-disrupting point mutations in the remaining allele of CIC, four of which are novel. One of these tumors also had a deleterious mutation in FUBP1. Only by integrating RNA expression and array CGH data, were we able to discover an exon-spanning homozygous microdeletion within the remaining allele of CIC in an additional tumor with 1p/19q co-deletion. Therefore we propose that the mutation rate might be underestimated when looking at sequence variants alone. In conclusion, the high frequency and the spectrum of CIC mutations in our 1p/19q-codeleted tumor cohort support the hypothesis that CIC acts as a tumor suppressor in these tumors, whereas FUBP1 might play only a minor role.

  4. A numerical approach for the direct computation of flows including fluid-solid interaction: modeling contact angle, film rupture, and dewetting

    CERN Document Server

    Mahady, K; Kondic, L

    2015-01-01

    In this paper, we present a computationally efficient method for including fluid-solid interactions into direct numerical simulations of the Navier--Stokes equations. This method is found to be as powerful as our earlier formulation [J. Comp. Phys., vol. 249: 243 (2015)], while outperforming the earlier method in terms of computational efficiency. The performance and efficacy of the presented method are demonstrated by computing contact angles of droplets at equilibrium. Furthermore, we study the instability of films due to destabilizing fluid-solid interactions, and discuss the influence of contact angle and inertial effects on film breakup. In particular, direct simulation results show an increase in the final characteristic length scales when compared to the predictions of a linear stability analysis, suggesting significant influence of nonlinear effects. Our results also show that emerging length scales differ, depending on a number of physical dimensions considered.

  5. Plasma diagnostic approach for the low-temperature deposition of silicon quantum dots using dual frequency PECVD

    Science.gov (United States)

    Sahu, B. B.; Yin, Y.; Lee, J. S.; Han, Jeon G.; Shiratani, M.

    2016-10-01

    Although studies of silicon (Si) quantum dots (QDs) were started just a few years ago, progress is noteworthy concerning unique film properties and their potential application for devices. In particular, relating to the Si QD process optimization, it is essential to control the deposition environment by studying the role of plasma parameters and atomic and molecular species in the process plasmas. In this work, we report on advanced material processes for the low-temperature deposition of Si QDs by utilizing radio frequency and ultrahigh frequency dual frequency (DF) plasma enhanced chemical vapor deposition (PECVD) method. DF PECVD can generate a very high plasma density in the range ~9  ×  1010 cm-3 to 3.2  ×  1011 cm-3 at a very low electron temperature (T e) ~ 1.5 to 2.4 eV. The PECVD processes, using a reactive mixture of H2/SiH4/NH3 gases, are carefully studied to investigate the operating regime and to optimize the deposition parameters by utilizing different plasma diagnostic tools. The analysis reveals that a higher ion flux at a higher plasma density on the substrate is conducive to enhancing the overall crystallinity of the deposited film. Along with high-density plasmas, a high concentration of atomic H and N is simultaneously essential for the high growth rate deposition of Si QDs. Numerous plasma diagnostics methods and film analysis tools are used to correlate the effect of plasma- and atomic-radical parameters on the structural and chemical properties of the deposited Si QD films prepared in the reactive mixtures of H2/SiH4/NH3 at various pressures.

  6. A systems-level approach to parental genomic imprinting: the imprinted gene network includes extracellular matrix genes and regulates cell cycle exit and differentiation.

    Science.gov (United States)

    Al Adhami, Hala; Evano, Brendan; Le Digarcher, Anne; Gueydan, Charlotte; Dubois, Emeric; Parrinello, Hugues; Dantec, Christelle; Bouschet, Tristan; Varrault, Annie; Journot, Laurent

    2015-03-01

    Genomic imprinting is an epigenetic mechanism that restrains the expression of ∼ 100 eutherian genes in a parent-of-origin-specific manner. The reason for this selective targeting of genes with seemingly disparate molecular functions is unclear. In the present work, we show that imprinted genes are coexpressed in a network that is regulated at the transition from proliferation to quiescence and differentiation during fibroblast cell cycle withdrawal, adipogenesis in vitro, and muscle regeneration in vivo. Imprinted gene regulation is not linked to alteration of DNA methylation or to perturbation of monoallelic, parent-of-origin-dependent expression. Overexpression and knockdown of imprinted gene expression alters the sensitivity of preadipocytes to contact inhibition and adipogenic differentiation. In silico and in cellulo experiments showed that the imprinted gene network includes biallelically expressed, nonimprinted genes. These control the extracellular matrix composition, cell adhesion, cell junction, and extracellular matrix-activated and growth factor-activated signaling. These observations show that imprinted genes share a common biological process that may account for their seemingly diverse roles in embryonic development, obesity, diabetes, muscle physiology, and neoplasm.

  7. Identification of novel mutations including a double mutation in patients with inherited cardiomyopathy by a targeted sequencing approach using the Ion Torrent PGM system.

    Science.gov (United States)

    Zhao, Yue; Cao, Hong; Song, Yindi; Feng, Yue; Ding, Xiaoxue; Pang, Mingjie; Zhang, Yunmei; Zhang, Hong; Ding, Jiahuan; Xia, Xueshan

    2016-06-01

    knowledge. This patient provided us with more information regarding the genotype-phenotype correlation between mutations of MYH7 and PRKAG2. Taken together, these findings provide insight into the molecular mechanisms underlying inherited cardiomyopathy. The mutations identified in this study may be further investigated in the future in order to improve the diagnosis and treatment of patients with inherited cardiomyopathy. Furthermore, our findings indicated that sequencing using the Ion Torrent PGM system is a useful approach for the identification of pathogenic mutations associated with inherited cardiomyopathy, and it may be used for the risk evaluation of individuals with a possible susceptibility to inherited cardiomyopathy. PMID:27082122

  8. Doping control analysis of 46 polar drugs in horse plasma and urine using a 'dilute-and-shoot' ultra high performance liquid chromatography-high resolution mass spectrometry approach.

    Science.gov (United States)

    Kwok, Wai Him; Choi, Timmy L S; Kwok, Karen Y; Chan, George H M; Wong, Jenny K Y; Wan, Terence S M

    2016-06-17

    The high sensitivity of ultra high performance liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS) allows the identification of many prohibited substances without pre-concentration, leading to the development of simple and fast 'dilute-and-shoot' methods for doping control for human and equine sports. While the detection of polar drugs in plasma and urine is difficult using liquid-liquid or solid-phase extraction as these substances are poorly extracted, the 'dilute-and-shoot' approach is plausible. This paper describes a 'dilute-and-shoot' UHPLC-HRMS screening method to detect 46 polar drugs in equine urine and plasma, including some angiotensin-converting enzyme (ACE) inhibitors, sympathomimetics, anti-epileptics, hemostatics, the new doping agent 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR), as well as two threshold substances, namely dimethyl sulfoxide and theobromine. For plasma, the sample (200μL) was protein precipitated using trichloroacetic acid, and the resulting supernatant was diluted using Buffer A with an overall dilution factor of 3. For urine, the sample (20μL) was simply diluted 50-fold with Buffer A. The diluted plasma or urine sample was then analysed using a UHPLC-HRMS system in full-scan ESI mode. The assay was validated for qualitative identification purpose. This straightforward and reliable approach carried out in combination with other screening procedures has increased the efficiency of doping control analysis in the laboratory. Moreover, since the UHPLC-HRMS data were acquired in full-scan mode, the method could theoretically accommodate an unlimited number of existing and new doping agents, and would allow a retrospectively search for drugs that have not been targeted at the time of analysis. PMID:27180888

  9. Treatment approach, delivery, and follow-up evaluation for cardiac rhythm disease management patients receiving radiation therapy: retrospective physician surveys including chart reviews at numerous centers.

    Science.gov (United States)

    Gossman, Michael S; Wilkinson, Jeffrey D; Mallick, Avishek

    2014-01-01

    In a 2-part study, we first examined the results of 71 surveyed physicians who provided responses on how they address the management of patients who maintained either a pacemaker or a defibrillator during radiation treatment. Second, a case review study is presented involving 112 medical records reviewed at 18 institutions to determine whether there was a change in the radiation prescription for the treatment of the target cancer, the method of radiation delivery, or the method of radiation image acquisition. Statistics are provided to illustrate the level of administrative policy; the level of communication between radiation oncologists and heart specialists; American Joint Committee on Cancer (AJCC) staging and classification; National Comprehensive Cancer Network (NCCN) guidelines; tumor site; patient׳s sex; patient׳s age; device type; manufacturer; live monitoring; and the reported decisions for planning, delivery, and imaging. This survey revealed that 37% of patient treatments were considered for some sort of change in this regard, whereas 59% of patients were treated without regard to these alternatives when available. Only 3% of all patients were identified with an observable change in the functionality of the device or patient status in comparison with 96% of patients with normal behavior and operating devices. Documented changes in the patient׳s medical record included 1 device exhibiting failure at 0.3-Gy dose, 1 device exhibiting increased sensor rate during dose delivery, 1 patient having an irregular heartbeat leading to device reprogramming, and 1 patient complained of twinging in the chest wall that resulted in a respiratory arrest. Although policies and procedures should directly involve the qualified medical physicist for technical supervision, their sufficient involvement was typically not requested by most respondents. No treatment options were denied to any patient based on AJCC staging, classification, or NCCN practice standards.

  10. Treatment approach, delivery, and follow-up evaluation for cardiac rhythm disease management patients receiving radiation therapy: Retrospective physician surveys including chart reviews at numerous centers

    Energy Technology Data Exchange (ETDEWEB)

    Gossman, Michael S., E-mail: MGossman@TSRCC.com [Regulation Directive Medical Physics, Russell, KY (United States); Wilkinson, Jeffrey D. [Medtronic, Inc., Mounds View, MN (United States); Mallick, Avishek [Department of Mathematics, Marshall University, Huntington, WV (United States)

    2014-01-01

    In a 2-part study, we first examined the results of 71 surveyed physicians who provided responses on how they address the management of patients who maintained either a pacemaker or a defibrillator during radiation treatment. Second, a case review study is presented involving 112 medical records reviewed at 18 institutions to determine whether there was a change in the radiation prescription for the treatment of the target cancer, the method of radiation delivery, or the method of radiation image acquisition. Statistics are provided to illustrate the level of administrative policy; the level of communication between radiation oncologists and heart specialists; American Joint Committee on Cancer (AJCC) staging and classification; National Comprehensive Cancer Network (NCCN) guidelines; tumor site; patient's sex; patient's age; device type; manufacturer; live monitoring; and the reported decisions for planning, delivery, and imaging. This survey revealed that 37% of patient treatments were considered for some sort of change in this regard, whereas 59% of patients were treated without regard to these alternatives when available. Only 3% of all patients were identified with an observable change in the functionality of the device or patient status in comparison with 96% of patients with normal behavior and operating devices. Documented changes in the patient's medical record included 1 device exhibiting failure at 0.3-Gy dose, 1 device exhibiting increased sensor rate during dose delivery, 1 patient having an irregular heartbeat leading to device reprogramming, and 1 patient complained of twinging in the chest wall that resulted in a respiratory arrest. Although policies and procedures should directly involve the qualified medical physicist for technical supervision, their sufficient involvement was typically not requested by most respondents. No treatment options were denied to any patient based on AJCC staging, classification, or NCCN practice standards.

  11. Modeling the first instant of the interaction between a liquid and a plasma jet with a compressible approach

    International Nuclear Information System (INIS)

    In this work, the numerical simulation of the interaction between a liquid jet and a plasma flow is investigated for understanding and predicting the physical parameters involved in the liquid plasma spraying process. This process is used for the production of high performance coatings to obtain thinner deposits (≤100 μm) than in conventional plasma spraying. The up-to-date goal is to describe the dispersion of liquid in order to understand the effect of injection conditions on the surface coating quality. This work proposes an original model for dealing with three-dimensional interactions between a plasma flow and a liquid phase with Volume Of Fluid (VOF) methods. A compressible model, capable of managing incompressible two-phase flows as well as compressible motions, is used. First comparisons with experimental photography show rather good agreement during the first moments of the injection. (authors)

  12. Reconstruction of the incident flux shape on the plasma-facing components of JET tokamak: 2D linear approach

    International Nuclear Information System (INIS)

    In this work, a deconvolution of the temperatures measured with thermocouples fitted inside the plasma-facing components of a controlled fusion machine is performed. A 2D pulse response is used which is obtained by the thermal quadrupole method. The shape and intensity of the plasma flux deposited at the surface of the component is calculated and some experimental results are presented. (J.S.)

  13. Elemental speciation by capillary electrophoresis with inductively coupled plasma spectrometry: A new approach by flow focusing® nebulization

    OpenAIRE

    Kovachev, Nikolay; Aguirre Pastor, Miguel Ángel; Hidalgo Núñez, Montserrat; Simitchiev, Kiril; Stefanova, Violeta M.; Kmetov, Veselin Y.; Canals Hernández, Antonio

    2014-01-01

    A novel system for Capillary Electrophoresis (CE) and Inductively Coupled Plasma (ICP) sample introduction that incorporates a dedicated Flow-Focusing® based nebulizer as aerosol generation unit is presented, aiming to provide high signal sensitivity and low detection limits for element speciation at short analysis times. To prove its viability, the system prototype constructed has been coupled to an inductively coupled plasma - optical emission spectrometer (ICP-OES) and an inductively coupl...

  14. Plasma properties

    International Nuclear Information System (INIS)

    The Magneto-Fluid Dynamics Division continues to study a broad range of problems originating in plasma physics. Its principal focus is fusion plasma physics, and most particularly topics of particular significance for the world magnetic fusion program. During the calendar year 1990 we explored a wide range of topics including RF-induced transport as a plasma control mechanism, edge plasma modelling, further statistical analysis of L and H mode tokamak plasmas, antenna design, simulation of the edge of a tokamak plasma and the L-H transition, interpretation of the CCT experimental results at UCLA, turbulent transport, studies in chaos, the validity of moment approximations to kinetic equations and improved neoclassical modelling. In more basic studies we examined the statistical mechanisms of Coulomb systems and applied plasma ballooning mode theory to conventional fluids in order to obtain novel fluid dynamics stability results. In space plasma physics we examined the problem of reconnection, the effect of Alfven waves in space environments, and correct formulation of boundary conditions of the Earth for waves in the ionosphere

  15. Successful Approaches to Helping Students--Including English Learners--Succeed in Elementary School. Parent Guide = Enfoques exitosos para ayudar a los estudiantes--incluyendo a los que aprenden ingles--a triunfar en la escuela primaria. Guia de padres

    Science.gov (United States)

    EdSource, 2007

    2007-01-01

    This guide informs parents about some instructional practices that work well for all elementary school students, in particular English learners. It includes questions parents can ask teachers and principals to help them understand how their children's school approaches teaching and learning. Both English and Spanish versions of the document are…

  16. Plasma physics and fusion plasma electrodynamics

    CERN Document Server

    Bers, Abraham

    2016-01-01

    Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as "linear, hydrodynamic descriptions" to be covered first because they are "easier", and postponing the "nonlinear and kinetic descriptions" for later because they are "difficult" is abandoned in this book. For teaching purpose...

  17. A LC-MS metabolomics approach to investigate the effect of raw apple intake in the rat plasma metabolome

    DEFF Research Database (Denmark)

    Rago, Daniela; Kristensen, Mette; Gürdeniz, Gözde;

    2013-01-01

    Fruit and vegetable consumption has been associated with several health benefits; however the mechanisms are largely unknown at the biochemical level. Our research aims to investigate whether plasma metabolome profiling can reflect biological effects after feeding rats with raw apple by using...

  18. An engineering approach to the design and construction of a small modular stellarator for magnetic confinement of plasma. SCR-1

    International Nuclear Information System (INIS)

    This paper briefly describes the design and construction of Stellarator of Costa Rica 1 (SCR-1) from an engineering perspective. SCR-1 is a small modular Stellarator for magnetic confinement of plasma developed by the Plasma Physics Group of the Instituto Tecnológico de Costa Rica (ITCR). The SCR-1 is based on the small Spanish Stellarator UST 1 (Ultra Small Torus 1), created by engineer Vicente Queral. Some of the characteristics of the SCR-1 are the following: it will be a 2-field period modular stellarator with an aspect ratio ≈ 6; low shear configuration with core and edge rotational transform equal to 0.32 and 0.28; it will employ stainless steel torus-shaped vacuum vessel which will hold a plasma with an average radius a ≈ 42.2 mm, a volume of 8 liters (0.008 m3), and major radius R = 238 mm. This plasma will be confined by a magnetic field (B ≈ 90 mT) given by 12 modular coils with 12 turns each, carrying a current of 725 A per turn providing a total toroidal field (TF) current of 8.7 kA-turn per coil. The coils will be supplied by a bank of cell batteries of 120 V. Typical length of the plasma pulse will be between 4 s to 10 s. The plasma heating will be achieved by electron cyclotron radio-frequency (ECH) from two magnetrons providing a total power of 5 kW, at a frequency of 2.45 GHz corresponding to the first harmonic (B0 = 87.8 mT). The expected electron temperature and density are 15 eV and 7x1016 m-3 respectively. The initial diagnostics on the SCR-1 will consist of a Langmuir probe with a displacement system, a heterodyne microwave interferometer (frequency of 28 GHz, corresponding to a wavelength of λ = 10.71 mm). The first plasma of the SCR-1 is expected at the beginning of 2012. (author)

  19. Plasma Treatments and Biomass Gasification

    International Nuclear Information System (INIS)

    Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. Syngas produced from biomass can be used to power internal combustion engines or, after purification, to supply fuel cells. Recent studies have shown the potential to improve conventional biomass processing by coupling a plasma reactor to a pyrolysis cyclone reactor. The role of the plasma is twofold: it acts as a purification stage by reducing production of tars and aerosols, and simultaneously produces a rich hydrogen syngas. In a first part of the paper we present results obtained from plasma treatment of pyrolysis oils. The outlet gas composition is given for various types of oils obtained at different experimental conditions with a pyrolysis reactor. Given the complexity of the mixtures from processing of biomass, we present a study with methanol considered as a model molecule. This experimental method allows a first modeling approach based on a combustion kinetic model suitable to validate the coupling of plasma with conventional biomass process. The second part of the paper is summarizing results obtained through a plasma-pyrolysis reactor arrangement. The goal is to show the feasibility of this plasma-pyrolysis coupling and emphasize more fundamental studies to understand the role of the plasma in the biomass treatment processes.

  20. Electromagnetic transients simulation using a shell approach for ITER cCXRS upper port plug due to plasma vertical displacement events

    Energy Technology Data Exchange (ETDEWEB)

    Belov, Alexander [Alphysica GmbH, Unterreut, 6, D76135 Karlsruhe (Germany); Gapionok, Elena, E-mail: elena.gapionok@alphysica.com [Alphysica GmbH, Unterreut, 6, D76135 Karlsruhe (Germany); Gornikel, Ilya; Kukhtin, Vladimir; Lamzin, Eugene [Alphysica GmbH, Unterreut, 6, D76135 Karlsruhe (Germany); Neubauer, Olaf [IEF-4 (Plasma Physics), Forschungszentrum Juelich, Association EURATOM-FZJ, D52425 Juelich (Germany); Sytchevsky, Sergey [Alphysica GmbH, Unterreut, 6, D76135 Karlsruhe (Germany)

    2011-10-15

    Transient electromagnetic (EM) analysis is presented focusing on main components of the ITER core charge exchange recombination spectroscopy (cCXRS) port plug developed by Forschungszentrum Juelich (FZJ), ITER-NL and UKAEA(CCFE) in 2009. The cCXRS primary function is to transfer the light in the visible part of spectra emitted by interaction of the plasma ions with a diagnostic neutral beam. The TYPHOON software package has been used for the EM analysis. The code is dedicated for simulation of transient electromagnetic processes using a shell approach in the integral-differential formulation to represent conducting structures with a set of multi-connected shells arbitrary located in a space. The advantage of the shell approach is a higher flexibility in modelling detailed structures as compared with widely used 3D models. On the other hand, the shell approach requires ultimate care in modelling relatively thick structures. These issues are discussed in the paper. Two vertical displacement events (VDE) which seem to result in the largest EM loads on the main cCXRS components have been agreed with FZJ and simulated. Transient electromagnetic processes caused by different sources have been considered separately, and then superimposed to obtain the total solution. Three types of transient processes for each type of VDE have been analyzed: (1) due to variations of a toroidal plasma current, shape and position and due to variations of poloidal field coils (PFC) and central solenoid (CS) currents, (2) due to variations of the Halo current and (3) due to variations of a toroidal magnetic flux of plasma. The analysis covers two options for electrical contact between the main shell (MS) of the port plug and the blanket shield module (BSM). The results are supposed to be used for benchmarking with independent 3D EM models developed for the upper port plug.

  1. Plasma chromograninx

    DEFF Research Database (Denmark)

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F;

    2014-01-01

    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk...... of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality....

  2. Ultracold neutral plasma expansion in two dimensions

    CERN Document Server

    Cummings, E A; Durfee, D S; Bergeson, S D

    2005-01-01

    We extend an isothermal thermal model of ultracold neutral plasma expansion to systems without spherical symmetry, and use this model to interpret new fluorescence measurements on these plasmas. By assuming a self-similar expansion, it is possible to solve the fluid equations analytically and to include velocity effects to predict the fluorescence signals. In spite of the simplicity of this approach, the model reproduces the major features of the experimental data.

  3. Impacts of recessed gate and fluoride-based plasma treatment approaches toward normally-off AlGaN/GaN HEMT.

    Science.gov (United States)

    Heo, Jun-Woo; Kim, Young-Jin; Kim, Hyun-Seok

    2014-12-01

    We report two approaches to fabricating high performance normally-off AIGaN/GaN high-electron mobility transistors (HEMTs). The fabrication techniques employed were based on recessed-metal-insulator-semiconductor (MIS) gate and recessed fluoride-based plasma treatment. They were selectively applied to the area under the gate electrode to deplete the two-dimensional electron gas (2-DEG) density. We found that the recessed gate structure was effective in shifting the threshold voltage by controlling the etching depth of gate region to reduce the AIGaN layer thickness to less than 8 nm. Likewise, the CF4 plasma treatment effectively incorporated negatively charged fluorine ions into the thin AIGaN barrier so that the threshold voltage shifted to higher positive values. In addition to the increased threshold voltage, experimental results showed a maximum drain current and a maximum transconductance of 315 mA/mm and 100 mS/mm, respectively, for the recessed-MIS gate HEMT, and 340 mA/mm and 330 mS/mm, respectively, for the fluoride-based plasma treated HEMT.

  4. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  5. Lecture notes on plasma physics

    International Nuclear Information System (INIS)

    The lectures cover the following topics in plasma physics: electrostatic plasma oscillations as described by the linearized Vlasov equation; properties of dielectric functions; the fluctuation dissipation theorem; 'dressed-particle' approach to plasma fluctuations; electron waves in a strongly magnetized plasma; propagation of ion acoustic density perturbations as described by the linearized ion Vlasov equation assuming Boltzmann distributed electrons; nonlinear waves. (Auth.)

  6. On Stability of Targets for Plasma Jet Induced Magnetoinertial Fusion

    CERN Document Server

    Samulyak, Roman; Kim, Hyoungekun

    2015-01-01

    The compression and stability of plasma targets for the plasma jet-induced magneto-inertial fusion (PJMIF) have been investigated via large scale simulations using the FronTier code capable of explicit tracking of material interfaces. In the PJMIF concept, a plasma liner, formed by the merger of a large number of radial, highly supersonic plasma jets, implodes on a magnetized plasma target and compresses it to conditions of the fusion ignition. A multi-stage computational approach for simulations of the liner-target interaction and the compression of plasma targets has been developed to minimize computing time. Simulations revealed important features of the target compression process, including instability and disintegration of targets. The non-uniformity of the leading edge of the liner, caused by plasma jets as well as oblique shock waves between them, leads to instabilities during the target compression. By using front tracking, the evolution of targets has been studied in 3-dimensional simulations. Optimi...

  7. Wettability and XPS analyses of nickel-phosphorus surfaces after plasma treatment: An efficient approach for surface qualification in mechatronic processes

    Science.gov (United States)

    Vivet, L.; Joudrier, A.-L.; Bouttemy, M.; Vigneron, J.; Tan, K. L.; Morelle, J. M.; Etcheberry, A.; Chalumeau, L.

    2013-06-01

    Electroless nickel-high-phosphorus Ni-P plating is known for its physical properties. In case of electronic and mechatronic assembly processes achieved under ambient conditions the wettability of the Ni-P layer under ambient temperature and ambient air stays a point of surface quality investigation. This contribution will be devoted to the study of the surface properties of Ni-P films for which we performed air plasma treatment. We focus our attention on the evolution of the surface wettability, using the classical sessile drop technique. Interpreting the results with the OWRK model we extract the polar and disperse surface tension components from which we deduced typical evolution of the surface properties with the different treatment settings. By controlling the variations of the parameters of the plasma exposure we are able to change the responses of our Ni-P sample from total hydrophobic to total hydrophilic behaviours. All the intermediate states can be reached by adapting the treatment parameters. So it is demonstrated that the apparent Ni-P surface properties can be fully adapted and the surface setting can be well characterized by wettability measurements. To deep our knowledge of the surface modifications induced by plasma we performed parallel SEM and XPS analyses which provide informations on the structure and the chemical composition of the surface for each set of treatment parameters. Using this double approach we were able to propose a correlation between the evolution of surface chemical composition and surface wettability which are completely governed by the plasma treatment conditions. Chemical parameters as the elimination of the carbon contamination, the progressive surface oxidation, and the slight incorporation of nitrogen due to the air plasma interaction are well associated with the evolution of the wettability properties. So a complete engineering for the Ni-P surface preparation has been established. The sessile drop method can be

  8. Wettability and XPS analyses of nickel–phosphorus surfaces after plasma treatment: An efficient approach for surface qualification in mechatronic processes

    International Nuclear Information System (INIS)

    Electroless nickel-high-phosphorus Ni–P plating is known for its physical properties. In case of electronic and mechatronic assembly processes achieved under ambient conditions the wettability of the Ni–P layer under ambient temperature and ambient air stays a point of surface quality investigation. This contribution will be devoted to the study of the surface properties of Ni–P films for which we performed air plasma treatment. We focus our attention on the evolution of the surface wettability, using the classical sessile drop technique. Interpreting the results with the OWRK model we extract the polar and disperse surface tension components from which we deduced typical evolution of the surface properties with the different treatment settings. By controlling the variations of the parameters of the plasma exposure we are able to change the responses of our Ni–P sample from total hydrophobic to total hydrophilic behaviours. All the intermediate states can be reached by adapting the treatment parameters. So it is demonstrated that the apparent Ni–P surface properties can be fully adapted and the surface setting can be well characterized by wettability measurements. To deep our knowledge of the surface modifications induced by plasma we performed parallel SEM and XPS analyses which provide informations on the structure and the chemical composition of the surface for each set of treatment parameters. Using this double approach we were able to propose a correlation between the evolution of surface chemical composition and surface wettability which are completely governed by the plasma treatment conditions. Chemical parameters as the elimination of the carbon contamination, the progressive surface oxidation, and the slight incorporation of nitrogen due to the air plasma interaction are well associated with the evolution of the wettability properties. So a complete engineering for the Ni–P surface preparation has been established. The sessile drop method can

  9. Wettability and XPS analyses of nickel–phosphorus surfaces after plasma treatment: An efficient approach for surface qualification in mechatronic processes

    Energy Technology Data Exchange (ETDEWEB)

    Vivet, L., E-mail: laurent.vivet@valeo.com [Valeo, Group Electronic Expertise and Development Services, 2 rue André Boulle 94 046 Créteil (France); Joudrier, A.-L.; Bouttemy, M.; Vigneron, J. [Institut Lavoisier de Versailles, UMR CNRS 8180, 45 Avenue des Etats-Unis, 78035 Versailles (France); Tan, K.L.; Morelle, J.M. [Valeo, Group Electronic Expertise and Development Services, 2 rue André Boulle 94 046 Créteil (France); Etcheberry, A. [Institut Lavoisier de Versailles, UMR CNRS 8180, 45 Avenue des Etats-Unis, 78035 Versailles (France); Chalumeau, L. [Egide, Site industriel du Sactar, 85500 Bollène (France)

    2013-06-01

    Electroless nickel-high-phosphorus Ni–P plating is known for its physical properties. In case of electronic and mechatronic assembly processes achieved under ambient conditions the wettability of the Ni–P layer under ambient temperature and ambient air stays a point of surface quality investigation. This contribution will be devoted to the study of the surface properties of Ni–P films for which we performed air plasma treatment. We focus our attention on the evolution of the surface wettability, using the classical sessile drop technique. Interpreting the results with the OWRK model we extract the polar and disperse surface tension components from which we deduced typical evolution of the surface properties with the different treatment settings. By controlling the variations of the parameters of the plasma exposure we are able to change the responses of our Ni–P sample from total hydrophobic to total hydrophilic behaviours. All the intermediate states can be reached by adapting the treatment parameters. So it is demonstrated that the apparent Ni–P surface properties can be fully adapted and the surface setting can be well characterized by wettability measurements. To deep our knowledge of the surface modifications induced by plasma we performed parallel SEM and XPS analyses which provide informations on the structure and the chemical composition of the surface for each set of treatment parameters. Using this double approach we were able to propose a correlation between the evolution of surface chemical composition and surface wettability which are completely governed by the plasma treatment conditions. Chemical parameters as the elimination of the carbon contamination, the progressive surface oxidation, and the slight incorporation of nitrogen due to the air plasma interaction are well associated with the evolution of the wettability properties. So a complete engineering for the Ni–P surface preparation has been established. The sessile drop method can

  10. Atomic physics in tokamak plasmas

    International Nuclear Information System (INIS)

    Tokamak discharges produce hydrogen-isotope plasmas in a quasi-steady state, with radial electron temperature, Tsub(e)(r), and density nsub(e)(r), distribution usually centrally peaked, with typical values Tsub(e)(0) approx.= 1 - 3 keV, nsub(e)(r) approx.= 1014 cm-3. Besides hydrogen, the plasma contains small quantities of carbon, oxygen, various construction or wall-conditioning materials such as Fe, Cr, Ni, Ti, Zr, Mo, and perhaps elements added for special diagnostic purposes, e.g., Si, Sc, Al, or noble gases. These elements are spatially fairly homogeneously distributed, with the different ionization states occurring near radial locations where Tsub(e)(r) approx.= Esub(i), the ionization potential. Thus, spectroscopic measurements of various plasma properties, such as ion temperatures, plasma motions or oscillations, radial transport rates, etc. are automatically endowed with spatial resolution. Furthermore the emitted spectra, even of heavier elements such as Fe or Ni, are fairly simple because only the ground levels are appreciably populated under the prevailing plasma conditions. Identification of near-ground transitions, including particularly magnetic dipole and intercombination transitions of ions with ionization potentials in the several keV range, and determination of their collisional and radiative transition probabilities will be required for development of appropriate diagnostics of tokamak-type plasma approaching the prospective fusion reactor conditions. (orig.)

  11. Plasma Ion Sources

    International Nuclear Information System (INIS)

    A wide variety of ion source types has been developed. Ion sources can provide beams of hundreds of amperes for fusion applications, nano-amperes for microprobe trace analysis and broad beams for ion implantation, space thrusters, industrial polymerisation and food sterilisation. Also it can be used in medical, military and accelerators applications. In this paper, three different types of plasma ion sources with different means for producing the discharge current and the ions extracting current from the plasma are studied. The various plasma described include, d.c glow discharge plasma, arc discharge plasma and radio frequency discharge plasma

  12. New approach for sustaining energetic, efficient and scalable non-equilibrium plasma in water vapours at atmospheric pressure

    International Nuclear Information System (INIS)

    Energetic and scalable non-equilibrium plasma was formed in pure water vapour at atmospheric pressure between wire-to-strip electrodes on a dielectric surface with one of the electrodes extended forming a conductive plane on the back side of the dielectric surface. The energy deposition increased by an order of magnitude compared with the conventional pulsed corona discharges under the same conditions. The scalability was demonstrated by operating two electrode assemblies with a common conductive plane between two dielectric layers. The energy yields for hydrogen and hydrogen peroxide generation were measured as ∼1.2 g H2/kWh and ∼4 g H2O2/kWh. (fast track communication)

  13. Solitons in relativistic laser-plasma interactions

    Institute of Scientific and Technical Information of China (English)

    XIE Bai-song; DU Shu-cheng

    2007-01-01

    Single or/and multipeak solitons in plasma under relativistic electromagnetic field are reviewed.The incident electromagnetic field iS allowed to have a zero or/and nonzero initial constant amplitude.Some interesting numerical results are obtained that include a high-number multipeak laser pulse and single or/and low-number multipeak plasma wake structures.It is also shown that there exists a combination of soliton and oscillation waves for plasma wake field.Also,the electron density exhibits multi-caviton structure or the combination of caviton and oscillation.A complete eigenvalue spectrum of parameters is given wherein some higher peak numbers of multipeak electromagnetic solitons in the plasma are included.Moreover, some interesting scaling laws are presented for field energy via numerical approaches.Some implications of results are discussed.

  14. Space plasma physics research

    Science.gov (United States)

    Comfort, Richard H.; Horwitz, James L.

    1993-01-01

    During the course of this grant, work was performed on a variety of topics and there were a number of significant accomplishments. A summary of these accomplishments is included. The topics studied include empirical model data base, data reduction for archiving, semikinetic modeling of low energy plasma in the inner terrestrial magnetosphere and ionosphere, O(+) outflows, equatorial plasma trough, and plasma wave ray-tracing studies. A list of publications and presentations which have resulted from this research is also included.

  15. Authentication of Kalix (N.E. Sweden) vendace caviar using inductively coupled plasma-based analytical techniques: Evaluation of different approaches

    International Nuclear Information System (INIS)

    Different analytical approaches for origin differentiation between vendace and whitefish caviars from brackish- and freshwaters were tested using inductively coupled plasma double focusing sector field mass spectrometry (ICP-SFMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). These approaches involve identifying differences in elemental concentrations or sample-specific isotopic composition (Sr and Os) variations. Concentrations of 72 elements were determined by ICP-SFMS following microwave-assisted digestion in vendace and whitefish caviar samples from Sweden (from both brackish and freshwater), Finland and USA, as well as in unprocessed vendace roe and salt used in caviar production. This data set allows identification of elements whose contents in caviar can be affected by salt addition as well as by contamination during production and packaging. Long-term method reproducibility was assessed for all analytes based on replicate caviar preparations/analyses and variations in element concentrations in caviar from different harvests were evaluated. The greatest utility for differentiation was demonstrated for elements with varying concentrations between brackish and freshwaters (e.g. As, Br, Sr). Elemental ratios, specifically Sr/Ca, Sr/Mg and Sr/Ba, are especially useful for authentication of vendace caviar processed from brackish water roe, due to the significant differences between caviar from different sources, limited between-harvest variations and relatively high concentrations in samples, allowing precise determination by modern analytical instrumentation. Variations in the 87Sr/86Sr ratio for vendace caviar from different harvests (on the order of 0.05-0.1%) is at least 10-fold less than differences between caviar processed from brackish and freshwater roe. Hence, Sr isotope ratio measurements (either by ICP-SFMS or by MC-ICP-MS) have great potential for origin differentiation. On the contrary, it was impossible to

  16. Plasma theory

    International Nuclear Information System (INIS)

    A series of lectures on plasma theory with the main headings: introduction; charged particles moving in em fields; the liquid model; transport phenomena in the plasma; wave propagation in plasmas; plasma instabilities. 57 figs. (qui)

  17. Fundamental aspects of plasma chemical physics kinetics

    CERN Document Server

    Capitelli, Mario; Colonna, Gianpiero; Esposito, Fabrizio; Gorse, Claudine; Hassouni, Khaled; Laricchiuta, Annarita; Longo, Savino

    2016-01-01

    Describing non-equilibrium "cold" plasmas through a chemical physics approach, this book uses the state-to-state plasma kinetics, which considers each internal state as a new species with its own cross sections. Extended atomic and molecular master equations are coupled with Boltzmann and Monte Carlo methods to solve the electron energy distribution function. Selected examples in different applied fields, such as microelectronics, fusion, and aerospace, are presented and discussed including the self-consistent kinetics in RF parallel plate reactors, the optimization of negative ion sources and the expansion of high enthalpy flows through nozzles of different geometries. The book will cover the main aspects of the state-to-state kinetic approach for the description of nonequilibrium cold plasmas, illustrating the more recent achievements in the development of kinetic models including the self-consistent coupling of master equations and Boltzmann equation for electron dynamics. To give a complete portrayal, the...

  18. Numerical simulations of plasma dynamics in a microsecond plasma opening switch

    International Nuclear Information System (INIS)

    The modified hydrodynamic approach is being used to study the characteristics of plasma motion due to magnetic pressure in plasma opening switch. The simulation code differs from the NRL counterpart with dividing of the plasma filled region into N sections and with using the experimentally measured current penetration parameters. The simulation of the switch opening phase is performed in terms of erosion mechanism of magnetically insulated vacuum gap forming. The code includes the circuit data which are regular for the DOUBLE generator operation regimes in the negative polarity of inner (potential) electrode. In the case of typical duration of the conduction phase (900 ns) the minimum needed plasma density was found to be about 1015 cm-3. The best fit of conduction current amplitude vs plasma density is I ∼ n0.23. The calculated characteristics of the switch opening phase were obtained to be very close to the experimental data

  19. Magnetized strongly coupled plasmas and how to realize them in a dusty plasma setup

    CERN Document Server

    Bonitz, M; Ott, T; Löwen, H

    2013-01-01

    Strongly coupled plasmas in which the interaction energy exceeds the kinetic energy play an important role in many astrophysical and laboratory systems including compact stars, laser plasmas and dusty plasmas. They exhibit many unusual collective properties, such as liquid or crystalline behaviour, peculiar oscillation spectra and transport properties. Recently, strongly coupled plasmas were studied in the presence of a strong magnetic field by computer simulations, and strong modifications of their transport properties and oscillation spectra were observed. While strong magnetization is common in stellar systems it is practically impossible to achieve in complex plasmas due to the large mass of the dust particles. Here we discuss a recently demonstrated approach to achieve very strong "magnetization" by a rotation of the neutral gas, and we present new results for macroscopic two-dimensional systems.

  20. Principle equivalence and practical difference between two approaches to plasma polarimetry: The Stokes vector formalism and the angular variables technique

    Energy Technology Data Exchange (ETDEWEB)

    Kravtsov, Yury A. [Maritime University, Szczecin (Poland); Bieg, Bohdan, E-mail: b.bieg@am.szczecin.pl [Maritime University, Szczecin (Poland); Chrzanowski, Janusz [Maritime University, Szczecin (Poland)

    2013-10-15

    In spite of well known different forms of the description of electromagnetic wave polarization state, up to now the evolution of the polarization state in weakly anisotropic media was described only by Stokes vector formalism (SVF) or quasi-istropic approximation (QIA). In this paper different approach is presented, based on angular variables technique (AVT): amplitude ratio and phase shift. It is shown that basic differential equations of angular variables technique can be derived directly from Stokes vector formalism. In turn Segre's equations of SVF are derived from the AVT equations, demonstrating the equivalence of the AVT and SVF formalisms. Also some practical distinctions between two approaches are pointed out. It is also shown that AVT explicitibly described interaction between Cotton–Mouton and Faraday effect.

  1. International movement of plasma and plasma contracting.

    Science.gov (United States)

    Farrugia, A

    2005-01-01

    Plasma fractionation is a global business characterised by technological stability, increasing consolidation and a high level of regulatory oversight. All these factors affect the ease with which plasma derivatives can be accessed in the world market. As domestic regulatory measures in the first world blood economies become increasingly resonant to the precautionary approach, the availability of plasma as a raw material, as well as its cost, become an increasingly significant component in the cost of the final product. This decreases the amount of plasma which fractionators are able to allocate for export activities. Also, regulatory standards in the country of manufacture will reflect priorities in that country which may not be similar to those in export markets, but which will affect entry to those markets. While many countries possess a fractionation capacity, the limiting factor in supply worldwide is the amount of plasma available, and nationalistic drivers for each country to have its own plant are inimical to product safety and supply. Rather, the provision of sufficient supplies of domestic plasma should be the focus of resource allocation, with a choice of an appropriate contract fractionator. However, contract fractionation too may be affected by domestic considerations unrelated to the needs of the country of plasma origin. This chapter will review the global plasma market and the influences on plasma and plasma product movement across national borders. Problems in ensuring adequate safety and supply will be identified, and some tentative approaches to the amelioration of current barriers to the provision of plasma derivatives will be outlined. PMID:16050160

  2. Arc Plasma Torch Modeling

    CERN Document Server

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  3. Identification of phosphorylated MYL12B as a potential plasma biomarker for septic acute kidney injury using a quantitative proteomic approach.

    Science.gov (United States)

    Wu, Fan; Dong, Xiu-Juan; Li, Yan-Yan; Zhao, Yan; Xu, Qiu-Lin; Su, Lei

    2015-01-01

    Acute kidney injury (AKI) is a common and increasingly encountered complication in hospitalized patients with critical illness in intensive care units (ICU). According to the etiology, Sepsis-induced AKI (SAKI) is a leading contributor to AKI and significantly has very poor prognosis, which might be related to the late detection when the elevation of BUN and serum creatinine (SCr) is used. Many genes are up-regulated in the damaged kidney with the corresponding protein products appearing in plasma and urine. Some of these are candidate biomarkers for more timely diagnosis of SAKI. Therefore, extensive research efforts over this past decade have been directed at the discovery and validation of novel SAKI biomarkers to detect injury prior to changes in kidney function, a number of serum and urinary proteins, including NGAL, KIM-1, cystatin-C, IL-18, and L-FABP, have been identified for predicting SAKI before a rise in BUN and serum creatinine in several experimental and clinical trainings. Unfortunately, an ideal biomarker of SAKI with highly sensitivity and specificity has not been identified yet. Recent progresses in quantitative proteomics have offered opportunities to discover biomarkers for SAKI. In the present study, kidney tissue samples from SAKI mice were analyzed by two-dimensional differential gel electrophoresis (2D-DIGE), and 4 up-regulated proteins, which were actin (ACTB), myosin regulatory light chain 12B (MYL12B), myosin regulatory light polypeptide 9 (MYL9), and myosin regulatory light chain 12A (MYL12A) were identified by matrix assisted laser desorption ionization-time of flight/time of flight mass spectrometry (MALDI-TOF/TOF MS). Among all the varied proteins, MYL12B was validated by western blot. Interestingly, there was no change between the SAKI and control kidney tissues, however, phosphorylated MYL12B was detected to be consistent with the proteomics data. Furthermore, phosphorylated MYL12B was found similarly to be increased in SAKI plasma

  4. Identification of phosphorylated MYL12B as a potential plasma biomarker for septic acute kidney injury using a quantitative proteomic approach

    Science.gov (United States)

    Wu, Fan; Dong, Xiu-Juan; Li, Yan-Yan; Zhao, Yan; Xu, Qiu-Lin; Su, Lei

    2015-01-01

    Acute kidney injury (AKI) is a common and increasingly encountered complication in hospitalized patients with critical illness in intensive care units (ICU). According to the etiology, Sepsis-induced AKI (SAKI) is a leading contributor to AKI and significantly has very poor prognosis, which might be related to the late detection when the elevation of BUN and serum creatinine (SCr) is used. Many genes are up-regulated in the damaged kidney with the corresponding protein products appearing in plasma and urine. Some of these are candidate biomarkers for more timely diagnosis of SAKI. Therefore, extensive research efforts over this past decade have been directed at the discovery and validation of novel SAKI biomarkers to detect injury prior to changes in kidney function, a number of serum and urinary proteins, including NGAL, KIM-1, cystatin-C, IL-18, and L-FABP, have been identified for predicting SAKI before a rise in BUN and serum creatinine in several experimental and clinical trainings. Unfortunately, an ideal biomarker of SAKI with highly sensitivity and specificity has not been identified yet. Recent progresses in quantitative proteomics have offered opportunities to discover biomarkers for SAKI. In the present study, kidney tissue samples from SAKI mice were analyzed by two-dimensional differential gel electrophoresis (2D-DIGE), and 4 up-regulated proteins, which were actin (ACTB), myosin regulatory light chain 12B (MYL12B), myosin regulatory light polypeptide 9 (MYL9), and myosin regulatory light chain 12A (MYL12A) were identified by matrix assisted laser desorption ionization-time of flight/time of flight mass spectrometry (MALDI-TOF/TOF MS). Among all the varied proteins, MYL12B was validated by western blot. Interestingly, there was no change between the SAKI and control kidney tissues, however, phosphorylated MYL12B was detected to be consistent with the proteomics data. Furthermore, phosphorylated MYL12B was found similarly to be increased in SAKI plasma

  5. Validation, using a chemometric approach, of gas chromatography-inductively coupled plasma-atomic emission spectrometry (GC-ICP-AES) for organotin determination

    Energy Technology Data Exchange (ETDEWEB)

    Aguerre, Sandrine; Pecheyran, Christophe; Lespes, Gaetane [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (L.C.A.B.I.E.), UMR 5034 CNRS Universite de Pau et des Pays de l' Adour, Avenue de l' Universite, 64012, Pau Cedex (France)

    2003-05-01

    The coupling between gas chromatography (GC) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) has been optimised using experimental designs. Four factors were considered in order to assist the crucial part of the coupling which is the analytes passing through the transfer line. The methodological approach based on the planning of fractional designs is described and justified according to an optimal experimentation. Then, the GC-ICP-AES-based method has been validated by means of statistical tests performed on calibration curves and evaluation of accuracy, precision and limits of detection (LOD), according to ISO standards and IUPAC recommendations. The absolute LOD are found to be quite similar to those obtained using flame photometer. Relative LOD ranged between 20 and 80 ng (Sn) L{sup -1} after liquid-liquid extraction of the analytes. When solid phase micro-extraction (SPME) is used, LOD are sub 10 ng (Sn) L{sup -1}. The repeatability is 3-10%, according to the extraction used. Analyses of reference sediment, fresh and waste waters confirm the suitability and capabilities of GC-ICP-AES for organotin determination in the environment. The statistical approach has been demonstrated to be a powerful methodological tool, enhancing the experimental part by providing reliable analytical results. (orig.)

  6. Effects of DC bias voltages on the RF-excited plasma-tissue interaction

    Science.gov (United States)

    Yang, Aijun; Liu, Dingxin; Wang, Xiaohua; Li, Jiafeng; Chen, Chen; Rong, Mingzhe; Kong, Michael G.

    2016-10-01

    We present in this study how DC bias voltage impacts on the fluxes of reactive species on the skin tissue by means of a plasma-tissue interaction model. The DC bias voltage inputs less than 2% of the total discharge power, and hence it has little influence on the whole plasma characteritics including the volume-averaged densities of reactive species and the heating effect. However, it pushes the plasma bulk towards the skin surface, which significantly changes the local plasma characteristics in the vicinity of the skin surface, and in consequence remarkably enhances the flux densities of reactive species on the skin tissue. With the consideration of plasma dosage and heat damage on the skin tissue, DC bias voltage is a better approach compared with the common approach of increasing the plasma power. Since the DC voltage is easy to apply on the human body, it is a promising approach for use in clincial applications.

  7. The ACCE method: an approach for obtaining quantitative or qualitative estimates of residual confounding that includes unmeasured confounding [v2; ref status: indexed, http://f1000r.es/54j

    Directory of Open Access Journals (Sweden)

    Eric G. Smith

    2015-04-01

    Full Text Available Background:  Nonrandomized studies typically cannot account for confounding from unmeasured factors.    Method:  A method is presented that exploits the recently-identified phenomenon of  “confounding amplification” to produce, in principle, a quantitative estimate of total residual confounding resulting from both measured and unmeasured factors.  Two nested propensity score models are constructed that differ only in the deliberate introduction of an additional variable(s that substantially predicts treatment exposure.  Residual confounding is then estimated by dividing the change in treatment effect estimate between models by the degree of confounding amplification estimated to occur, adjusting for any association between the additional variable(s and outcome.   Results:  Several hypothetical examples are provided to illustrate how the method produces a quantitative estimate of residual confounding if the method’s requirements and assumptions are met.  Previously published data is used to illustrate that, whether or not the method routinely provides precise quantitative estimates of residual confounding, the method appears to produce a valuable qualitative estimate of the likely direction and general size of residual confounding.   Limitations:  Uncertainties exist, including identifying the best approaches for: 1 predicting the amount of confounding amplification, 2 minimizing changes between the nested models unrelated to confounding amplification, 3 adjusting for the association of the introduced variable(s with outcome, and 4 deriving confidence intervals for the method’s estimates (although bootstrapping is one plausible approach.   Conclusions:  To this author’s knowledge, it has not been previously suggested that the phenomenon of confounding amplification, if such amplification is as predictable as suggested by a recent simulation, provides a logical basis for estimating total residual confounding. The method

  8. Optical modulator including grapene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  9. Plasma physics

    CERN Document Server

    Cairns, R A

    1985-01-01

    This book is intended as an introduction to plasma physics at a level suitable for advanced undergraduates or beginning postgraduate students in physics, applied mathematics or astrophysics. The main prerequisite is a knowledge of electromagnetism and of the associated mathematics of vector calculus. SI units are used throughout. There is still a tendency amongst some plasma physics researchers to· cling to C.g.S. units, but it is the author's view that universal adoption of SI units, which have been the internationally agreed standard since 1960, is to be encouraged. After a short introductory chapter, the basic properties of a plasma con­ cerning particle orbits, fluid theory, Coulomb collisions and waves are set out in Chapters 2-5, with illustrations drawn from problems in nuclear fusion research and space physics. The emphasis is on the essential physics involved and (he theoretical and mathematical approach has been kept as simple and intuitive as possible. An attempt has been made to draw attention t...

  10. Plasma turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  11. Reliability and Construct Validity of the Psychopathic Personality Inventory-Revised in a Swedish Non-Criminal Sample – A Multimethod Approach including Psychophysiological Correlates of Empathy for Pain

    Science.gov (United States)

    Sörman, Karolina; Nilsonne, Gustav; Howner, Katarina; Tamm, Sandra; Caman, Shilan; Wang, Hui-Xin; Ingvar, Martin; Edens, John F.; Gustavsson, Petter; Lilienfeld, Scott O; Petrovic, Predrag; Fischer, Håkan; Kristiansson, Marianne

    2016-01-01

    Cross-cultural investigation of psychopathy measures is important for clarifying the nomological network surrounding the psychopathy construct. The Psychopathic Personality Inventory-Revised (PPI-R) is one of the most extensively researched self-report measures of psychopathic traits in adults. To date however, it has been examined primarily in North American criminal or student samples. To address this gap in the literature, we examined PPI-R’s reliability, construct validity and factor structure in non-criminal individuals (N = 227) in Sweden, using a multimethod approach including psychophysiological correlates of empathy for pain. PPI-R construct validity was investigated in subgroups of participants by exploring its degree of overlap with (i) the Psychopathy Checklist: Screening Version (PCL:SV), (ii) self-rated empathy and behavioral and physiological responses in an experiment on empathy for pain, and (iii) additional self-report measures of alexithymia and trait anxiety. The PPI-R total score was significantly associated with PCL:SV total and factor scores. The PPI-R Coldheartedness scale demonstrated significant negative associations with all empathy subscales and with rated unpleasantness and skin conductance responses in the empathy experiment. The PPI-R higher order Self-Centered Impulsivity and Fearless Dominance dimensions were associated with trait anxiety in opposite directions (positively and negatively, respectively). Overall, the results demonstrated solid reliability (test-retest and internal consistency) and promising but somewhat mixed construct validity for the Swedish translation of the PPI-R. PMID:27300292

  12. Applied plasma physics

    International Nuclear Information System (INIS)

    Applied Plasma Physics is a major sub-organizational unit of the MFE Program. It includes Fusion Plasma Theory and Experimental Plasma Research. The Fusion Plasma Theory group has the responsibility for developing theoretical-computational models in the general areas of plasma properties, equilibrium, stability, transport, and atomic physics. This group has responsibility for giving guidance to the mirror experimental program. There is a formal division of the group into theory and computational; however, in this report the efforts of the two areas are not separated since many projects have contributions from members of both. Under the Experimental Plasma Research Program, we are developing the intense, pulsed neutral-beam source (IPINS) for the generation of a reversed-field configuration on 2XIIB. We are also studying the feasibility of utilizing certain neutron-detection techniques as plasma diagnostics in the next generation of thermonuclear experiments

  13. Applied plasma physics

    International Nuclear Information System (INIS)

    Applied Plasma Physics is a major sub-organizational unit of the MFE Porgram. It includes Fusion Plasma Theory and Experimental Plasma Research. Fusion Plasma Theory has the responsibility for developing theoretical-computational models in the general areas of plasma properties, equilibrium, stability, transport, and atomic physics. This group has responsibility for giving guidance to the mirror experimental program. There is a formal division of the group into theory and computational; however, in this report the efforts of the two areas are not separated since many projects have contributions from members of both. Under Experimental Plasma Research, we are developing the intense, pulsed ion-neutral source (IPINS) for the generation of a reversed-field configuration on 2XIIB. We are also studying the feasibility of utilizing certain neutron-detection techniques as plasma diagnostics in the next generation of thermonuclear experiments

  14. Applied plasma physics

    International Nuclear Information System (INIS)

    Applied Plasma Physics is a major sub-organizational unit of the Magnetic Fusion Energy (MFE) Program. It includes Fusion Plasma Theory and Experimental Plasma Research. The Fusion Plasma Theory group has the responsibility for developing theoretical-computational models in the general areas of plasma properties, equilibrium, stability, transport, and atomic physics. This group has responsibility for giving guidance to the mirror experimental program. There is a formal division of the group into theory and computational; however, in this report the efforts of the two areas are not separated since many projects have contributions from members of both. Under the Experimental Plasma Research Program we are developing a neutral-beam source, the intense, pulsed ion-neutral source (IPINS), for the generation of a reversed-field configuration on 2XIIB. We are also studying the feasibility of using certain neutron-detection techniques as plasma diagnostics in the next generation of thermonuclear experiments

  15. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  16. Plasma properties

    International Nuclear Information System (INIS)

    This paper discusses the following topics: MHD plasma activity: equilibrium, stability and transport; statistical analysis; transport studies; edge physics studies; wave propagation analysis; basic plasma physics and fluid dynamics; space plasma; and numerical methods

  17. A Shotgun Proteomic Approach Reveals That Fe Deficiency Causes Marked Changes in the Protein Profiles of Plasma Membrane and Detergent-Resistant Microdomain Preparations from Beta vulgaris Roots.

    Science.gov (United States)

    Gutierrez-Carbonell, Elain; Takahashi, Daisuke; Lüthje, Sabine; González-Reyes, José Antonio; Mongrand, Sébastien; Contreras-Moreira, Bruno; Abadía, Anunciación; Uemura, Matsuo; Abadía, Javier; López-Millán, Ana Flor

    2016-08-01

    In the present study we have used label-free shotgun proteomic analysis to examine the effects of Fe deficiency on the protein profiles of highly pure sugar beet root plasma membrane (PM) preparations and detergent-resistant membranes (DRMs), the latter as an approach to study microdomains. Altogether, 545 proteins were detected, with 52 and 68 of them changing significantly with Fe deficiency in PM and DRM, respectively. Functional categorization of these proteins showed that signaling and general and vesicle-related transport accounted for approximately 50% of the differences in both PM and DRM, indicating that from a qualitative point of view changes induced by Fe deficiency are similar in both preparations. Results indicate that Fe deficiency has an impact in phosphorylation processes at the PM level and highlight the involvement of signaling proteins, especially those from the 14-3-3 family. Lipid profiling revealed Fe-deficiency-induced decreases in phosphatidic acid derivatives, which may impair vesicle formation, in agreement with the decreases measured in proteins related to intracellular trafficking and secretion. The modifications induced by Fe deficiency in the relative enrichment of proteins in DRMs revealed the existence of a group of cytoplasmic proteins that appears to be more attached to the PM in conditions of Fe deficiency. PMID:27321140

  18. Analytic device including nanostructures

    KAUST Repository

    Di, Fabrizio, E.

    2015-07-02

    A device for detecting an analyte in a sample comprising: an array including a plurality of pixels, each pixel including a nanochain comprising: a first nanostructure, a second nanostructure, and a third nanostructure, wherein size of the first nanostructure is larger than that of the second nanostructure, and size of the second nanostructure is larger than that of the third nanostructure, and wherein the first nanostructure, the second nanostructure, and the third nanostructure are positioned on a substrate such that when the nanochain is excited by an energy, an optical field between the second nanostructure and the third nanostructure is stronger than an optical field between the first nanostructure and the second nanostructure, wherein the array is configured to receive a sample; and a detector arranged to collect spectral data from a plurality of pixels of the array.

  19. Plasma Catalysis: Synergistic Effects at the Nanoscale.

    Science.gov (United States)

    Neyts, Erik C; Ostrikov, Kostya Ken; Sunkara, Mahendra K; Bogaerts, Annemie

    2015-12-23

    Thermal-catalytic gas processing is integral to many current industrial processes. Ever-increasing demands on conversion and energy efficiencies are a strong driving force for the development of alternative approaches. Similarly, synthesis of several functional materials (such as nanowires and nanotubes) demands special processing conditions. Plasma catalysis provides such an alternative, where the catalytic process is complemented by the use of plasmas that activate the source gas. This combination is often observed to result in a synergy between plasma and catalyst. This Review introduces the current state-of-the-art in plasma catalysis, including numerous examples where plasma catalysis has demonstrated its benefits or shows future potential, including CO2 conversion, hydrocarbon reforming, synthesis of nanomaterials, ammonia production, and abatement of toxic waste gases. The underlying mechanisms governing these applications, as resulting from the interaction between the plasma and the catalyst, render the process highly complex, and little is known about the factors leading to the often-observed synergy. This Review critically examines the catalytic mechanisms relevant to each specific application. PMID:26619209

  20. The center for multiscale plasma dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kevrekidis, Yannis G [Princeton Univ., Princeton, NJ (United States)

    2015-01-20

    This final report describes research performed in Princeton University, led by Professor Yannis G. Kevrekidis, over a period of six years (August 1, 2014 to July 31, 2010, including a one-year, no-cost extension) as part of the Center for Multiscale Plasma Dynamics led by the University of Maryland. The work resulted in the development and implementation of several multiscale algorithms based on the equation-free approach pioneered by the PI, including its applications in plasma dynamics problems. These algoriithms include coarse projective integration and coarse stability/bifurcation computations. In the later stages of the work, new links were made between this multiscale, coarse-graining approach and advances in data mining/machine learning algorithms.

  1. General Information about Plasma Cell Neoplasms (Including Multiple Myeloma)

    Science.gov (United States)

    ... or certain chemicals . Tests that examine the blood, bone marrow, and urine are used to detect (find) and ... amyloidosis. Radiation therapy : Radiation therapy is given for bone lesions of the spine . Chemotherapy: Chemotherapy is given to ...

  2. Treatment Option Overview (Plasma Cell Neoplasms Including Multiple Myeloma)

    Science.gov (United States)

    ... or certain chemicals . Tests that examine the blood, bone marrow, and urine are used to detect (find) and ... amyloidosis. Radiation therapy : Radiation therapy is given for bone lesions of the spine . Chemotherapy: Chemotherapy is given to ...

  3. Treatment of electronic waste to recover metal values using thermal plasma coupled with acid leaching – A response surface modeling approach

    International Nuclear Information System (INIS)

    Highlights: ► Sentences/phrases were modified. ► Necessary discussions for different figures were included. ► More discussion have been included on the flue gas analysis. ► Queries to both the reviewers have been given. - Abstract: The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values as a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency.

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

    Science.gov (United States)

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

    2014-01-01

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

  5. Plasma Medicine

    Science.gov (United States)

    Laroussi, M.; Kong, M. G.; Morfill, G.; Stolz, W.

    2012-05-01

    Foreword R. Satava and R. J. Barker; Part I. Introduction to Non-equilibrium Plasma, Cell Biology, and Contamination: 1. Introduction M. Laroussi; 2. Fundamentals of non-equilibrium plasmas M. Kushner and M. Kong; 3. Non-equilibrium plasma sources M. Laroussi and M. Kong; 4. Basic cell biology L. Greene and G. Shama; 5. Contamination G. Shama and B. Ahlfeld; Part II. Plasma Biology and Plasma Medicine: 6. Common healthcare challenges G. Isbary and W. Stolz; 7. Plasma decontamination of surfaces M. Kong and M. Laroussi; 8. Plasma decontamination of gases and liquids A. Fridman; 9. Plasma-cell interaction: prokaryotes M. Laroussi and M. Kong; 10. Plasma-cell interaction: eukaryotes G. Isbary, G. Morfill and W. Stolz; 11. Plasma based wound healing G. Isbary, G. Morfill and W. Stolz; 12. Plasma ablation, surgery, and dental applications K. Stalder, J. Woloszko, S. Kalghatgi, G. McCombs, M. Darby and M. Laroussi; Index.

  6. Reconstruction of the incident flux shape on the plasma-facing components of JET tokamak: 2D linear approach; Reconstruction de la forme du flux incident sur les composants face au plasma du tokamak JET: approche 2D lineaire

    Energy Technology Data Exchange (ETDEWEB)

    Gardarein, J.L.; Corre, Y.; Reichle, R. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Rigollet, F.; Le Niliot, Ch. [Universite de Provence (IUSTI UMR CNRS 6595), 13 - Marseille (France)

    2006-07-01

    In this work, a deconvolution of the temperatures measured with thermocouples fitted inside the plasma-facing components of a controlled fusion machine is performed. A 2D pulse response is used which is obtained by the thermal quadrupole method. The shape and intensity of the plasma flux deposited at the surface of the component is calculated and some experimental results are presented. (J.S.)

  7. Development and validation of a fast and uniform approach to quantify β-lactam antibiotics in human plasma by solid phase extraction-liquid chromatography-electrospray-tandem mass spectrometry.

    Science.gov (United States)

    Colin, Pieter; De Bock, Lies; T'jollyn, Huybrecht; Boussery, Koen; Van Bocxlaer, Jan

    2013-01-15

    Monitoring of plasma antibiotic concentrations is necessary for individualization of antimicrobial chemotherapy dosing in special patient populations. One of these special populations of interest are the post-bariatric surgery patients. Until today, little is known on the effect of this procedure on drug disposition and efficacy. Therefore, close monitoring of antimicrobial plasma concentrations in these patients is warranted. A fast and uniform ultra-high-performance liquid chromatography (UPLC) method with tandem mass spectrometric detection (MS/MS) has been developed and qualified for the simultaneous quantification of β-lactam antibiotics in human plasma. Compounds included in this multi-component analysis are: amoxicillin, ampicillin, phenoxymethylpenicillin, piperacillin, cefuroxime, cefadroxil, flucloxacillin, meropenem, cefepime, ceftazidime, tazobactam, linezolid and cefazolin. After spiking of five different stable isotope labelled internal standards, plasma samples were prepared for UPLC-MS/MS analysis by mixed-mode solid phase extraction. The developed method was proven to be free of (relative) matrix effects and proved to be reliable for the quantification of 12 out of 13 β-lactam antibiotics. As a proof of concept the method has been applied to plasma samples obtained from a healthy volunteer treated with amoxicillin. The analytical method is suitable for use in a therapeutic drug monitoring setting, providing the clinician with reliable measurements on β-lactam antibiotic plasma concentrations in a timely manner.

  8. EDITORIAL: Focus on Plasma Medicine

    Science.gov (United States)

    Morfill, G. E.; Kong, M. G.; Zimmermann, J. L.

    2009-11-01

    'Plasma Healthcare' is an emerging interdisciplinary research topic of rapidly growing importance, exploring considerable opportunities at the interface of plasma physics, chemistry and engineering with life sciences. Some of the scientific discoveries reported so far have already demonstrated clear benefits for healthcare in areas of medicine, food safety, environmental hygiene, and cosmetics. Examples include ongoing studies of prion inactivation, chronic wound treatment and plasma-mediated cancer therapy. Current research ranges from basic physical processes, plasma chemical design, to the interaction of plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells, viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and (iv) living human, animal and plant tissues in the presence of biofluids. Of diverse interests in this new field is the need for hospital disinfection, in particular with respect to the alarming increase in bacterial resistance to antibiotics, the concomitant needs in private practices, nursing homes etc, the applications in personal hygiene—and the enticing possibility to 'design' plasmas as possible pharmaceutical products, employing ionic as well as molecular agents for medical treatment. The 'delivery' of the reactive plasma agents occurs at the gaseous level, which means that there is no need for a carrier medium and access to the treatment surface is optimal. This focus issue provides a close look at the current state of the art in Plasma Medicine with a number of forefront research articles as well as an introductory review. Focus on Plasma Medicine Contents Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination Helen C Baxter, Patricia R Richardson, Gaynor A Campbell, Valeri I Kovalev, Robert Maier, James S Barton, Anita C Jones, Greg DeLarge, Mark Casey and Robert L Baxter Inactivation factors of spore-forming bacteria using low

  9. Dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)

    2004-05-31

    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  10. Plasma lens experiments at the Final Focus Test Beam

    Energy Technology Data Exchange (ETDEWEB)

    Barletta, B. [California Univ., Los Angeles, CA (United States)]|[Lawrence Berkeley Lab., CA (United States); Chattopadhyay, S. [Lawrence Berkeley Lab., CA (United States); Chen, P. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)] [and others

    1993-04-01

    We intend to carry out a series of plasma lens experiments at the Final Focus Test Beam facility at SLAC. These experiments will be the first to study the focusing of particle beams by plasma focusing devices in the parameter regime of interest for high energy colliders, and is expected to lead to plasma lens designs capable of unprecedented spot sizes. Plasma focusing of positron beams will be attempted for the first time. We will study the effects of lens aberrations due to various lens imperfections. Several approaches will be applied to create the plasma required including laser ionization and beam ionization of a working gas. At an increased bunch population of 2.5 {times} 10{sup 10}, tunneling ionization of a gas target by an electron beam -- an effect which has never been observed before -- should be significant. The compactness of our device should prove to be of interest for applications at the SLC and the next generation linear colliders.

  11. Stopping Power for Strong Beam-Plasma Coupling

    Science.gov (United States)

    Gericke, Dirk O.

    2001-10-01

    The slowing down process of charged particles in plasma targets is investigated for the case of strong beam-plasma coupling. Strong beam-plasma correlations can be considered using the collision operator of the quantum Boltzmann equation. As a first step, dynamic screening is included in the first Born approximation. This approach gives good results for moderate beam-plasma coupling (Zb Γ^3/2 Bethe-formula, the standard model of the stopping power (Bethe plus Bloch corrections and Barkas terms), the Li & Petrasso formula and simulation data (MD and PIC), is given. This comparison clearly shows the advantage of the proposed model: it smoothly interpolates between the classical low velocity regime, where strong coupling effects occur, and the high velocity quantum regime, where collective modes are important. In the latter case, the experimentally proven Bethe-formula is obtained. Furthermore, it matches the simulation data for moderate as well as strong beam-plasma coupling.

  12. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura;

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma...... membrane include ABC transporters, vacuolar (V-type) H+ pumps, and P-type pumps. These pumps all utilize ATP as a fuel for energizing pumping. This review focuses on the physiological roles of plasma membrane P-type pumps, as they represent the major ATP hydrolytic activity in this membrane....

  13. Plasma processing for VLSI

    CERN Document Server

    Einspruch, Norman G

    1984-01-01

    VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

  14. Magnetospheric plasma waves

    International Nuclear Information System (INIS)

    A brief history of plasma wave observations in the Earth's magnetosphere is recounted and a classification of the identified plasma wave phenomena is presented. The existence of plasma waves is discussed in terms of the characteristic frequencies of the plasma, the energetic particle populations and the proposed generation mechanisms. Examples are given for which plasmas waves have provided information about the plasma parameters and particle characteristics once a reasonable theory has been developed. Observational evidence and arguments by analogy to the observed Earth plasma wave processes are used to identify plasma waves that may be significant in other planetary magnetospheres. The similarities between the observed characteristics of the terrestrial kilometric radiation and radio bursts from Jupiter, Saturn and possibly Uranus are stressed. Important scientific problems concerning plasma wave processes in the solar system and beyond are identified and discussed. Models for solar flares, flare star radio outbursts and pulsars include elements which are also common to the models for magnetospheric radio bursts. Finally, a listing of the research and development in terms of instruments, missions, laboratory experiments, theory and computer simulations needed to make meaningful progress on the outstanding scientific problems of plasma wave research is given. (Auth.)

  15. A Systematic Analysis of the Sensitivity of Plasma Pharmacokinetics to Detect Differences in the Pulmonary Performance of Inhaled Fluticasone Propionate Products Using a Model-Based Simulation Approach.

    Science.gov (United States)

    Weber, Benjamin; Hochhaus, Guenther

    2015-07-01

    The role of plasma pharmacokinetics (PK) for assessing bioequivalence at the target site, the lung, for orally inhaled drugs remains unclear. A validated semi-mechanistic model, considering the presence of mucociliary clearance in central lung regions, was expanded for quantifying the sensitivity of PK studies in detecting differences in the pulmonary performance (total lung deposition, central-to-peripheral lung deposition ratio, and pulmonary dissolution characteristics) between test (T) and reference (R) inhaled fluticasone propionate (FP) products. PK bioequivalence trials for inhaled FP were simulated based on this PK model for a varying number of subjects and T products. The statistical power to conclude bioequivalence when T and R products are identical was demonstrated to be 90% for approximately 50 subjects. Furthermore, the simulations demonstrated that PK metrics (area under the concentration time curve (AUC) and C max) are capable of detecting differences between T and R formulations of inhaled FP products when the products differ by more than 20%, 30%, and 25% for total lung deposition, central-to-peripheral lung deposition ratio, and pulmonary dissolution characteristics, respectively. These results were derived using a rather conservative risk assessment approach with an error rate of <10%. The simulations thus indicated that PK studies might be a viable alternative to clinical studies comparing pulmonary efficacy biomarkers for slowly dissolving inhaled drugs. PK trials for pulmonary efficacy equivalence testing should be complemented by in vitro studies to avoid false positive bioequivalence assessments that are theoretically possible for some specific scenarios. Moreover, a user-friendly web application for simulating such PK equivalence trials with inhaled FP is provided.

  16. Metallic targets ablation by laser plasma production in a vacuum

    International Nuclear Information System (INIS)

    A model of metallic target ablation and metallic plasma production by laser irradiation is reported. The model considers laser energy absorption by the plasma, electron emission from hot targets and ion flux to the target from the plasma as well as an electric sheath produced at the target-plasma interface. The proposed approach takes into account that the plasma, partially shields the laser radiation from the target, and also converts absorbed laser energy to kinetic and potential energies of the charged plasma particles, which they transport not only through the ambient vacuum but also through the electrostatic sheath to the solid surface. Therefore additional plasma heating by the accelerated emitted electrons and target heating caused by bombardment of it by the accelerated ions are considered. A system of equations, including equations for solid heat conduction, plasma generation, and plasma expansion, is solved self-consistently. The results of calculations explain the measured dependencies of ablation yield (μ g/pulse) for Al, Ni, and Ti targets on laser fluence in range of (5–21)J/cm2 published previously by Torrisi et al

  17. Laser-aided diagnostics of plasmas and gases

    CERN Document Server

    Muraoka, K

    2000-01-01

    Updated and expanded from the original Japanese edition, Laser-Aided Diagnostics of Gases and Plasmas takes a unique approach in treating laser-aided diagnostics. The book unifies the subject by joining applications instead of describing each application as a totally separate system. In taking this approach, it highlights the relative strengths of each method and shows how they can complement each other in the study of gases and plasmas.The first part of the book presents a general introduction to the laser-aided study of gases and plasmas, including the various principles and hardware needed for each method, while the second part describes the applications of each general system in detail.Beneficial to a wide spectrum of academic and industrial researchers, this book provides a solid examination of the various options and methods available when involved in the analysis and diagnostics of gases and plasmas.

  18. What is a plasma?

    Energy Technology Data Exchange (ETDEWEB)

    Intrator, Thomas P. [Los Alamos National Laboratory

    2012-08-30

    This introduction will define the plasma fourth state of matter, where we find plasmas on earth and beyond, and why they are useful. There are applications to many consumer items, fusion energy, scientific devices, satellite communications, semiconductor processing, spacecraft propulsion, and more. Since 99% of our observable universe is ionized gas, plasma physics determines many important features of astrophysics, space physics, and magnetosphere physics in our solar system. We describe some plasma characteristics, examples in nature, some useful applications, how to create plasmas. A brief introduction to the theoretical framework includes the connection between kinetic and fluid descriptions, quasi neutrality, Debye shielding, ambipolar electric fields, some plasma waves. Hands-on demonstrations follow. More complete explanations will follow next week.

  19. Plasma kinetic theory

    CERN Document Server

    Swanson, Donald Gary

    2008-01-01

    Developed from the lectures of a leading expert in plasma wave research, Plasma Kinetic Theory provides the essential material for an introductory course on plasma physics as well as the basis for a more advanced course on kinetic theory. Exploring various wave phenomena in plasmas, it offers wide-ranging coverage of the field. After introducing basic kinetic equations and the Lenard–Balescu equation, the book covers the important Vlasov–Maxwell equations. The solutions of these equations in linear and quasilinear approximations comprise the majority of kinetic theory. Another main topic in kinetic theory is to assess the effects of collisions or correlations in waves. The author discusses the effects of collisions in magnetized plasma and calculates the different transport coefficients, such as pressure tensor, viscosity, and thermal diffusion, that depend on collisions. With worked examples and problem sets that enable sound comprehension, this text presents a detailed, mathematical approach to app...

  20. Basic plasma physics

    CERN Document Server

    Ghosh, Basudev

    2014-01-01

    Basic Plasma Physics is designed to serve as an introductory compact textbook for advanced undergraduate, postgraduate and research students taking plasma physics as one of their subject of study for the first time. It covers the current syllabus of plasma physics offered by the most universities and technical institutions. The book requires no background in plasma physics but only elementary knowledge of basic physics and mathematics. Emphasis has been given on the analytical approach. Topics are developed from first principle so that the students can learn through self-study. One chapter has been devoted to describe some practical aspects of plasma physics. Each chapter contains a good number of solved and unsolved problems and a variety of review questions, mostly taken from recent examination papers. Some classroom experiments described in the book will surely help students as well as instructors.

  1. Contoured-gap coaxial guns for imploding plasma liner experiments

    Science.gov (United States)

    Witherspoon, F. D.; Case, A.; Brockington, S.; Cassibry, J. T.; Hsu, S. C.

    2014-10-01

    Arrays of supersonic, high momentum flux plasma jets can be used as standoff compression drivers for generating spherically imploding plasma liners for driving magneto-inertial fusion, hence the name plasma-jet-driven MIF (PJMIF). HyperV developed linear plasma jets for the Plasma Liner Experiment (PLX) at LANL where two guns were successfully tested. Further development at HyperV resulted in achieving the PLX goal of 8000 μg at 50 km/s. Prior work on contoured-gap coaxial guns demonstrated an approach to control the blowby instability and achieved substantial performance improvements. For future plasma liner experiments we propose to use contoured-gap coaxial guns with small Minirailgun injectors. We will describe such a gun for a 60-gun plasma liner experiment. Discussion topics will include impurity control, plasma jet symmetry and topology (esp. related to uniformity and compactness), velocity capability, and techniques planned for achieving gun efficiency of >50% using tailored impedance matched pulse forming networks. Mach2 and UAH SPH code simulations will be included. Work supported by US DOE DE-FG02-05ER54810.

  2. Validation of the quantitative determination of tetrahydrocannabinol and its two major metabolites in plasma by UHPLC/MS-MS according to the total error approach

    OpenAIRE

    Dubois, Nathalie; Paccau, A.; De Backer, Benjamin; Charlier, Corinne

    2012-01-01

    In Belgium, driving under the influence (DUI) of cannabis is prohibited and has severe legal consequences for the driver if the blood plasma concentration of Δ9-tetrahydrocannabinol (THC) exceeds 1 µg/L. A method to quantify low concentrations of THC and its hydroxylated (THC-OH) and carboxylated (THC-COOH) metabolites in plasma was developed for DUI but also for other applications. Ultra-high-performance liquid chromatography coupled to mass spectrometry seems to be a very convenient method ...

  3. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  4. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  5. Theory of gas discharge plasma

    CERN Document Server

    Smirnov, Boris M

    2015-01-01

    This book presents the theory of gas discharge plasmas in a didactical way. It explains the processes in gas discharge plasmas. A gas discharge plasma is an ionized gas which is supported by an external electric field. Therefore its parameters are determined by processes in it. The properties of a gas discharge plasma depend on its gas component, types of external fields, their geometry and regimes of gas discharge. Fundamentals of a gas discharge plasma include elementary, radiative and transport processes which are included in its kinetics influence. They are represented in this book together with the analysis of simple gas discharges. These general principles are applied to stationary gas discharge plasmas of helium and argon. The analysis of such plasmas under certain conditions is theoretically determined by numerical plasma parameters for given regimes and conditions.

  6. Relativistic spherical plasma waves

    Science.gov (United States)

    Bulanov, S. S.; Maksimchuk, A.; Schroeder, C. B.; Zhidkov, A. G.; Esarey, E.; Leemans, W. P.

    2012-02-01

    Tightly focused laser pulses that diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we study theoretically and numerically relativistic spherical wake waves and their properties, including wave breaking.

  7. Vol. 6: Plasma Physics

    International Nuclear Information System (INIS)

    Problems of modern physics and the situation with physical research in Ukraine are considered. Programme of the conference includes scientific and general problems. Its proceeding are published in 6 volumes. The papers presented in this volume refer to plasma physics

  8. Comparison between two alternative approaches for the analysis of polarization evolution of EM waves in a nonuniform, fully anisotropic medium. A magnetized plasma; Paragone tra due metodi alternativi per l'analisi della polarizzazione di onde elettromagnetiche in un plasma magnetizzato

    Energy Technology Data Exchange (ETDEWEB)

    Segre, S. E. [ENEA, Div. Fusione, Centro Ricerche Frascati, Frascati, Rome (Italy)

    2001-07-01

    A comparison is made between two alternative approaches for the analysis of polarization evolution of em waves in a magnetized plasma. The two approaches are the Coupled Wave-Equation Formalism (CWF) and the Stokes Vector Formalism (SVF). After brief descriptions of the two formalisms the correspondence between them is spelled out. The two formalisms are then compared and their relative advantages and limitations are discussed. [Italian] Si fa un confronto tra due metodi alternativi per l'analisi della polarizzazione di onde elettromagnetiche in un plasma magnetizzato. I due metodi sono il formalismo delle equazioni accoppiate per le onde (Coupled Wave-equation Formalism) e il formalismo del vettore di Stokes (Stokes Vector Formalism). Dopo brevi descrizioni dei due formalismi, viene esplicitata la corrispondenza tra essi quindi i due formalismi vengono confrontati e si discutono i loro meriti e limiti relativi.

  9. Electron cyclotron waves transmission: new approach for the characterization of electron distribution functions in Tokamak hot plasmas; La transmission d`ondes cyclotroniques electroniques: une approche nouvelle pour caracteriser les fonctions de distribution electronique des plasmas chauds de Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Michelot, Y.

    1995-10-01

    Fast electrons are one of the basic ingredients of plasma operations in many existing thermonuclear fusion research devices. However, the understanding of fast electrons dynamics during creation and sustainment of the superthermal electrons tail is far for being satisfactory. For this reason, the Electron Cyclotron Transmission (ECT) diagnostic was implemented on Tore Supra tokamak. It consists on a microwave transmission system installed on a vertical chord crossing the plasma center and working in the frequency range 77-109 GHz. Variations of the wave amplitude during the propagation across the plasma may be due to refraction and resonant absorption. For the ECT, the most common manifestation of refraction is a reduction of the received power density with respect to the signal detected in vacuum, due to the spreading and deflection of the wave beam. Wave absorption is observed in the vicinity of the electron cyclotron harmonics and may be due both to thermal plasma and to superthermal electron tails. It has a characteristic frequency dependence due to the relativistic mass variation in the wave-electron resonance condition. This thesis presents the first measurements of: the extraordinary mode optical depth at the third harmonics, the electron temperature from the width of a cyclotron absorption line and the relaxation times of the electron distribution during lower hybrid current drive from the ordinary mode spectral superthermal absorption line at the first harmonic. (J.S.). 175 refs., 110 figs., 9 tabs., 3 annexes.

  10. Interaction of High Intensity Electromagnetic Waves with Plasmas: Final Report

    International Nuclear Information System (INIS)

    The focus of our work during the duration of this grant was on the following areas: (a) the fundamental plasma physics of intense laser-plasma interactions, including the nonlinear excitation of plasma waves for accelerator applications, as well as the recently discovered by us phenomenon of the relativistic bi-stability of relativistic plasma waves driven by a laser beatwave; (b) interaction of high power microwave beams with magnetized plasma, including some of the recently discovered by us phenomena such as the Undulator Induced Transparency (UIT) as well as the new approaches to dynamic manipulation of microwave pulses; (c) investigations of the multi-color laser pulse interactions in the plasma, including the recently discovered by us phenomenon of Electromagnetic Cascading (EC) and the effect of the EC of three-dimensional dynamics of laser pulses (enhanced/suppressed selffocusing etc.); (d) interaction of high-current electron beams with the ambient plasma in the context of Fast Ignitor (FI) physics, with the emphasis on the nonlinear dynamics of the Weibel instability and beam filamentation.

  11. Interaction of High Intensity Electromagnetic Waves with Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    G. Shvets

    2008-10-03

    The focus of our work during the duration of this grant was on the following areas: (a) the fundamental plasma physics of intense laser-plasma interactions, including the nonlinear excitation of plasma waves for accelerator applications, as well as the recently discovered by us phenomenon of the relativistic bi-stability of relativistic plasma waves driven by a laser beatwave; (b) interaction of high power microwave beams with magnetized plasma, including some of the recently discovered by us phenomena such as the Undulator Induced Transparency (UIT) as well as the new approaches to dynamic manipulation of microwave pulses; (c) investigations of the multi-color laser pulse interactions in the plasma, including the recently discovered by us phenomenon of Electromagnetic Cascading (EC) and the effect of the EC of three-dimensional dynamics of laser pulses (enhanced/suppressed selffocusing etc.); (d) interaction of high-current electron beams with the ambient plasma in the context of Fast Ignitor (FI) physics, with the emphasis on the nonlinear dynamics of the Weibel instability and beam filamentation.

  12. Radiofrequency power in plasmas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document includes the various communications that were presented at the 11th topical conference on radio frequency power in plasmas which took place in Palm Springs in May 1995. It includes current diffusion studies to assess the non-inductive current deposition profiles, experiments for plasma to reach quickly an equilibrium state, and modelling of electrons in plasma. Some comparison studies also reveal the efficiency of the Quasi-Optical Grill antenna for reactor applications. Finally, a scenario for efficient mode conversion heating in the ion cyclotron range of frequency is presented. Separate abstracts were prepared for the 6 papers in this volume. (TEC).

  13. Tensile adhesion test measurements on plasma-sprayed coatings

    Science.gov (United States)

    Berndt, C. C.

    1986-01-01

    Adhesion measurements on plasma-sprayed coatings are briefly studied, including a critical analysis of the experimental scatter for duplicate tests. The application of a simple method which presents adhesion strength data in a fracture mechanics perspective is demonstrated. Available data are analyzed in a way which suggests an approach to finding the overall defect contribution to reducing the apparent strength of coatings.

  14. A ‘frozen electric-field’ approach to simulate repetitively pulsed nanosecond plasma discharges and ignition of hydrogen-air mixtures

    Science.gov (United States)

    Nagaraja, Sharath; Yang, Vigor

    2014-09-01

    High-fidelity modelling of nanosecond repetitively pulsed discharges (NRPDs) is burdened by the multiple time and length scales and large chemistry mechanisms involved, which prohibit detailed analyses and parametric studies. In the present work, we propose a ‘frozen electric-field’ modelling approach to expedite the NRPD simulations without adverse effects on the solution accuracy. First, a burst of nanosecond voltage pulses is simulated self-consistently until the discharge reaches a stationary state. The calculated spatial distributions and temporal evolution of the electric field, electron density and electron energy during the last pulse are then stored in a library and the electrical characteristics of subsequent pulses are frozen at these values. This strategy allows the timestep for numerical integration to be increased by four orders of magnitude (from 10-13 to 10-9 s), thereby significantly improving the computational efficiency of the process. Reduced calculations of a burst of 50 discharge pulses show good agreement with the predictions from a complete plasma model (electrical characteristics calculated during each pulse). The error in species densities is less than 20% at the centre of the discharge volume and about 30% near the boundaries. The deviations in temperature, however, are much lower, at 5% in the entire domain. The model predictions are in excellent agreement with measured ignition delay times and temperatures in H2-air mixtures subject to dielectric barrier NRPD over a pressure range of 54-144 Torr with equivalence ratios of 0.7-1.2. The OH density increases with pressure and triggers low-temperature fuel oxidation, which leads to rapid temperature rise and ignition. The ignition delay decreases by a factor of 2, with an increase in pressure from 54 to 144 Torr. In contrast, an increase in the H2-air equivalence ratio from 0.7 to 1.2 marginally decreases the ignition delay by about 20%. This behaviour is attributed to the insensitivity

  15. Including Magnetostriction in Micromagnetic Models

    Science.gov (United States)

    Conbhuí, Pádraig Ó.; Williams, Wyn; Fabian, Karl; Nagy, Lesleis

    2016-04-01

    The magnetic anomalies that identify crustal spreading are predominantly recorded by basalts formed at the mid-ocean ridges, whose magnetic signals are dominated by iron-titanium-oxides (Fe3-xTixO4), so called "titanomagnetites", of which the Fe2.4Ti0.6O4 (TM60) phase is the most common. With sufficient quantities of titanium present, these minerals exhibit strong magnetostriction. To date, models of these grains in the pseudo-single domain (PSD) range have failed to accurately account for this effect. In particular, a popular analytic treatment provided by Kittel (1949) for describing the magnetostrictive energy as an effective increase of the anisotropy constant can produce unphysical strains for non-uniform magnetizations. I will present a rigorous approach based on work by Brown (1966) and by Kroner (1958) for including magnetostriction in micromagnetic codes which is suitable for modelling hysteresis loops and finding remanent states in the PSD regime. Preliminary results suggest the more rigorously defined micromagnetic models exhibit higher coercivities and extended single domain ranges when compared to more simplistic approaches.

  16. 1990's annual report of INPE's Plasma Associated Laboratory

    International Nuclear Information System (INIS)

    This is the 1990's annual report of INPE's Plasma Associated Laboratory it contains information on current research developed at the laboratory including quiescent plasma, magnetized plasma, plasma centrifuge, plasma and radiation (gyrotron), ionic propulsion, and toroidal plasma. (A.C.A.S.)

  17. Novel aspects of plasma control in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Humphreys, D.; Jackson, G.; Walker, M.; Welander, A. [General Atomics P.O. Box 85608, San Diego, California 92186-5608 (United States); Ambrosino, G.; Pironti, A. [CREATE/University of Naples Federico II, Napoli (Italy); Vries, P. de; Kim, S. H.; Snipes, J.; Winter, A.; Zabeo, L. [ITER Organization, St. Paul Lez durance Cedex (France); Felici, F. [Eindhoven University of Technology, Eindhoven (Netherlands); Kallenbach, A.; Raupp, G.; Treutterer, W. [Max-Planck Institut für Plasmaphysik, Garching (Germany); Kolemen, E. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543-0451 (United States); Lister, J.; Sauter, O. [Centre de Recherches en Physique des Plasmas, Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland); Moreau, D. [CEA, IRFM, 13108 St. Paul-lez Durance (France); Schuster, E. [Lehigh University, Bethlehem, Pennsylvania (United States)

    2015-02-15

    ITER plasma control design solutions and performance requirements are strongly driven by its nuclear mission, aggressive commissioning constraints, and limited number of operational discharges. In addition, high plasma energy content, heat fluxes, neutron fluxes, and very long pulse operation place novel demands on control performance in many areas ranging from plasma boundary and divertor regulation to plasma kinetics and stability control. Both commissioning and experimental operations schedules provide limited time for tuning of control algorithms relative to operating devices. Although many aspects of the control solutions required by ITER have been well-demonstrated in present devices and even designed satisfactorily for ITER application, many elements unique to ITER including various crucial integration issues are presently under development. We describe selected novel aspects of plasma control in ITER, identifying unique parts of the control problem and highlighting some key areas of research remaining. Novel control areas described include control physics understanding (e.g., current profile regulation, tearing mode (TM) suppression), control mathematics (e.g., algorithmic and simulation approaches to high confidence robust performance), and integration solutions (e.g., methods for management of highly subscribed control resources). We identify unique aspects of the ITER TM suppression scheme, which will pulse gyrotrons to drive current within a magnetic island, and turn the drive off following suppression in order to minimize use of auxiliary power and maximize fusion gain. The potential role of active current profile control and approaches to design in ITER are discussed. Issues and approaches to fault handling algorithms are described, along with novel aspects of actuator sharing in ITER.

  18. Novel aspects of plasma control in ITER

    Science.gov (United States)

    Humphreys, D.; Ambrosino, G.; de Vries, P.; Felici, F.; Kim, S. H.; Jackson, G.; Kallenbach, A.; Kolemen, E.; Lister, J.; Moreau, D.; Pironti, A.; Raupp, G.; Sauter, O.; Schuster, E.; Snipes, J.; Treutterer, W.; Walker, M.; Welander, A.; Winter, A.; Zabeo, L.

    2015-02-01

    ITER plasma control design solutions and performance requirements are strongly driven by its nuclear mission, aggressive commissioning constraints, and limited number of operational discharges. In addition, high plasma energy content, heat fluxes, neutron fluxes, and very long pulse operation place novel demands on control performance in many areas ranging from plasma boundary and divertor regulation to plasma kinetics and stability control. Both commissioning and experimental operations schedules provide limited time for tuning of control algorithms relative to operating devices. Although many aspects of the control solutions required by ITER have been well-demonstrated in present devices and even designed satisfactorily for ITER application, many elements unique to ITER including various crucial integration issues are presently under development. We describe selected novel aspects of plasma control in ITER, identifying unique parts of the control problem and highlighting some key areas of research remaining. Novel control areas described include control physics understanding (e.g., current profile regulation, tearing mode (TM) suppression), control mathematics (e.g., algorithmic and simulation approaches to high confidence robust performance), and integration solutions (e.g., methods for management of highly subscribed control resources). We identify unique aspects of the ITER TM suppression scheme, which will pulse gyrotrons to drive current within a magnetic island, and turn the drive off following suppression in order to minimize use of auxiliary power and maximize fusion gain. The potential role of active current profile control and approaches to design in ITER are discussed. Issues and approaches to fault handling algorithms are described, along with novel aspects of actuator sharing in ITER.

  19. Recent progress in plasma modelling at INFN-LNS

    Science.gov (United States)

    Neri, L.; Castro, G.; Torrisi, G.; Galatà, A.; Mascali, D.; Celona, L.; Gammino, S.

    2016-02-01

    At Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), the development of intense ion and proton sources has been supported by a great deal of work on the modelling of microwave generated plasmas for many years. First, a stationary version of the particle-in-cell code was developed for plasma modelling starting from an iterative strategy adopted for the space charge dominated beam transport simulations. Electromagnetic properties of the plasma and full-waves simulations are now affordable for non-homogenous and non-isotropic magnetized plasma via "cold" approximation. The effects of Coulomb collisions on plasma particles dynamics was implemented with the Langevin formalism, instead of simply applying the Spitzer 90° collisions through a Monte Carlo technique. A wide database of different cross sections related to reactions occurring in a hydrogen plasma was implemented. The next step consists of merging such a variety of approaches for retrieving an "as-a-whole" picture of plasma dynamics in ion sources. The preliminary results will be summarized in the paper for a microwave discharge ion source designed for intense and high quality proton beams production, proton source for European Spallation Source project. Even if the realization of a predictive software including the complete processes involved in plasma formation is still rather far, a better comprehension of the source behavior is possible and so the simulations may support the optimization phase.

  20. Recent progress in plasma modelling at INFN-LNS.

    Science.gov (United States)

    Neri, L; Castro, G; Torrisi, G; Galatà, A; Mascali, D; Celona, L; Gammino, S

    2016-02-01

    At Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), the development of intense ion and proton sources has been supported by a great deal of work on the modelling of microwave generated plasmas for many years. First, a stationary version of the particle-in-cell code was developed for plasma modelling starting from an iterative strategy adopted for the space charge dominated beam transport simulations. Electromagnetic properties of the plasma and full-waves simulations are now affordable for non-homogenous and non-isotropic magnetized plasma via "cold" approximation. The effects of Coulomb collisions on plasma particles dynamics was implemented with the Langevin formalism, instead of simply applying the Spitzer 90° collisions through a Monte Carlo technique. A wide database of different cross sections related to reactions occurring in a hydrogen plasma was implemented. The next step consists of merging such a variety of approaches for retrieving an "as-a-whole" picture of plasma dynamics in ion sources. The preliminary results will be summarized in the paper for a microwave discharge ion source designed for intense and high quality proton beams production, proton source for European Spallation Source project. Even if the realization of a predictive software including the complete processes involved in plasma formation is still rather far, a better comprehension of the source behavior is possible and so the simulations may support the optimization phase. PMID:26931913

  1. Recent progress in plasma modelling at INFN-LNS

    Energy Technology Data Exchange (ETDEWEB)

    Neri, L., E-mail: neri@lns.infn.it; Castro, G.; Mascali, D.; Celona, L.; Gammino, S. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Torrisi, G. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università Mediterranea di Reggio Calabria, Via Graziella, 89100 Reggio Calabria (Italy); Galatà, A. [INFN-Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Legnaro, Padova (Italy)

    2016-02-15

    At Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), the development of intense ion and proton sources has been supported by a great deal of work on the modelling of microwave generated plasmas for many years. First, a stationary version of the particle-in-cell code was developed for plasma modelling starting from an iterative strategy adopted for the space charge dominated beam transport simulations. Electromagnetic properties of the plasma and full-waves simulations are now affordable for non-homogenous and non-isotropic magnetized plasma via “cold” approximation. The effects of Coulomb collisions on plasma particles dynamics was implemented with the Langevin formalism, instead of simply applying the Spitzer 90° collisions through a Monte Carlo technique. A wide database of different cross sections related to reactions occurring in a hydrogen plasma was implemented. The next step consists of merging such a variety of approaches for retrieving an “as-a-whole” picture of plasma dynamics in ion sources. The preliminary results will be summarized in the paper for a microwave discharge ion source designed for intense and high quality proton beams production, proton source for European Spallation Source project. Even if the realization of a predictive software including the complete processes involved in plasma formation is still rather far, a better comprehension of the source behavior is possible and so the simulations may support the optimization phase.

  2. EDITORIAL: Focus on Plasma Medicine

    Science.gov (United States)

    Morfill, G. E.; Kong, M. G.; Zimmermann, J. L.

    2009-11-01

    'Plasma Healthcare' is an emerging interdisciplinary research topic of rapidly growing importance, exploring considerable opportunities at the interface of plasma physics, chemistry and engineering with life sciences. Some of the scientific discoveries reported so far have already demonstrated clear benefits for healthcare in areas of medicine, food safety, environmental hygiene, and cosmetics. Examples include ongoing studies of prion inactivation, chronic wound treatment and plasma-mediated cancer therapy. Current research ranges from basic physical processes, plasma chemical design, to the interaction of plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells, viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and (iv) living human, animal and plant tissues in the presence of biofluids. Of diverse interests in this new field is the need for hospital disinfection, in particular with respect to the alarming increase in bacterial resistance to antibiotics, the concomitant needs in private practices, nursing homes etc, the applications in personal hygiene—and the enticing possibility to 'design' plasmas as possible pharmaceutical products, employing ionic as well as molecular agents for medical treatment. The 'delivery' of the reactive plasma agents occurs at the gaseous level, which means that there is no need for a carrier medium and access to the treatment surface is optimal. This focus issue provides a close look at the current state of the art in Plasma Medicine with a number of forefront research articles as well as an introductory review. Focus on Plasma Medicine Contents Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination Helen C Baxter, Patricia R Richardson, Gaynor A Campbell, Valeri I Kovalev, Robert Maier, James S Barton, Anita C Jones, Greg DeLarge, Mark Casey and Robert L Baxter Inactivation factors of spore-forming bacteria using low

  3. Dietary omega-3 polyunsaturated fatty acids alter the fatty acid composition of hepatic and plasma bioactive lipids in C57BL/6 mice: a lipidomic approach.

    Directory of Open Access Journals (Sweden)

    Kayode A Balogun

    Full Text Available BACKGROUND: Omega (n-3 polyunsaturated fatty acids (PUFA are converted to bioactive lipid components that are important mediators in metabolic and physiological pathways; however, which bioactive compounds are metabolically active, and their mechanisms of action are still not clear. We investigated using lipidomic techniques, the effects of diets high in n-3 PUFA on the fatty acid composition of various bioactive lipids in plasma and liver. METHODOLOGY AND PRINCIPAL FINDINGS: Female C57BL/6 mice were fed semi-purified diets (20% w/w fat containing varying amounts of n-3 PUFA before mating, during gestation and lactation, and until weaning. Male offspring were continued on their mothers' diets for 16 weeks. Hepatic and plasma lipids were extracted in the presence of non-naturally occurring internal standards, and tandem electrospray ionization mass spectrometry methods were used to measure the fatty acyl compositions. There was no significant difference in total concentrations of phospholipids in both groups. However, there was a significantly higher concentration of eicosapentaenoic acid containing phosphatidylcholine (PC, lysophosphatidylcholine (LPC, and cholesteryl esters (CE (p < 0.01 in the high n-3 PUFA group compared to the low n-3 PUFA group in both liver and plasma. Plasma and liver from the high n-3 PUFA group also had a higher concentration of free n-3 PUFA (p < 0.05. There were no significant differences in plasma concentrations of different fatty acyl species of phosphatidylethanolamine, triglycerides, sphingomyelin and ceramides. CONCLUSIONS/SIGNIFICANCE: Our findings reveal for the first time that a diet high in n-3 PUFA caused enrichment of n-3 PUFA in PC, LPC, CE and free fatty acids in the plasma and liver of C57BL/6 mice. PC, LPC, and unesterified free n-3 PUFA are important bioactive lipids, thus altering their fatty acyl composition will have important metabolic and physiological roles.

  4. Microphysics of cosmic plasmas

    CERN Document Server

    Bykov, Andrei; Cargill, Peter; Dendy, Richard; Wit, Thierry; Raymond, John

    2014-01-01

    This title presents a review of the detailed aspects of the physical processes that underlie the observed properties, structures and dynamics of cosmic plasmas. An assessment of the status of understanding of microscale processes in all astrophysical collisionless plasmas is provided. The topics discussed include  turbulence in astrophysical and solar system plasmas as a phenomenological description of their dynamic properties on all scales; observational, theoretical and modelling aspects of collisionless magnetic reconnection; the formation and dynamics of shock waves; and a review and assessment of microprocesses, such as the hierarchy of plasma instabilities, non-local and non-diffusive transport processes and ionisation and radiation processes.  In addition, some of the lessons that have been learned from the extensive existing knowledge of laboratory plasmas as applied to astrophysical problems are also covered.   This volume is aimed at graduate students and researchers active in the areas of cosmi...

  5. Plasma antennas

    CERN Document Server

    Anderson, Theodore

    2011-01-01

    The plasma antenna is an emerging technology that partially or fully utilizes ionized gas as the conducting medium instead of metal to create an antenna. The key advantages of plasma antennas are that they are highly reconfigurable and can be turned on and off. The disadvantage is that the plasma antennas require energy to be ionized. This unique resource provides you with a solid understanding of the efficient design and prototype development of plasma antennas, helping you to meet the challenge of reducing the power required to ionize the gas at various plasma densities. You also find thorou

  6. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up

  7. Physics issues associated with low-beta plasma generators

    Science.gov (United States)

    Borovsky, Joseph E.

    1992-01-01

    Kinetic aspects of MHD generators are explored by examining the propagation of dense, low-beta streams of plasma. Three situations are considered: the basic principles of plasma-stream propagation, the propagation of plasma streams into vacuum, and the propagation of plasma streams into ambient plasmas. These three situations are analogous to plasma generators, plasma generators with vacuum loads, and plasma generators with plasma loads. Kinetic (microphysics) aspects include oscillations of the generator plasma, the effects of diocotron instabilities, the acceleration of particles, the starvation of current systems, and plasma-wave production.

  8. [Industrial pasteurization of plasma and criteria of quality].

    Science.gov (United States)

    Burnouf-Radosevich, M; Burnouf, T; Huart, J J

    1993-01-01

    The approach followed in the design of a large-scale pasteurization treatment (60 degrees C for 10 hours in the liquid state) of fresh frozen plasma is presented. Various aspects thought to influence the viral safety of such a product are discussed. They are based largely upon the fact that, although it is subjected to a specific viral inactivation treatment, this plasma does not benefit from any fractionation steps known to participate in the potential elimination of infectious agents during the manufacture of plasma derivatives. Consequently, the plasma is obtained from regular plasmapheresis donors, and the plasma donations used to make the pool must be negative for anti-HIV-1 and -2, anti-HCV, anti-HBc, anti-HTLV-1 and -2, HBs antigen and parvovirus B19 antigen, and have a normal level of ALT. The batch size is limited to 100 plasma units to limit the potential infectious risk associated with very large batches, especially if an infectious agent, resistant to pasteurization, is present. Pasteurization has been chosen for this procedure, as applied to plasma derivatives, has been shown to inactivate a broad spectrum of viruses, both enveloped and non-enveloped. The process is relatively simple. The frozen plasma units are opened, and the plasmas are mixed and thawed at 30 degrees C to avoid the formation of cryoprecipitate. The liquid plasma is transferred to a sterilized container and stabilizers are added. The mixture is then transferred to the pasteurization unit to be heat-treated at 60 degrees C for at least 10 hours under gentle mixing. Following cooling, the mixture is ultrafiltered to eliminate the stabilizers and to concentrate the plasma pool to its initial volume. The plasma is sterile-filtered, then dispensed into bottles and frozen. Virus validation of this pasteurization process, carried out by independent virology laboratories, have confirmed the ability of the process to inactivate more than 4 to 6 logs of non-enveloped or enveloped, DNA or RNA

  9. A metabolomics approach used to profile plasma from portal-arterial pigs revealed differences between breads incurred by dietary fibra and protein contents

    DEFF Research Database (Denmark)

    Nielsen, Kirstine Lykke; Hedemann, Mette Skou; Lærke, Helle Nygaard;

    2014-01-01

    A liquid chromatography–MS (LC-MS) metabolomics analysis of plasma from portal–arterial catheterised pigs fed breads prepared with whole-grain rye or wheat flour with added concentrated arabinoxylan (AX) or β-glucan (BG) was conducted. Comparison of the effects of concentrated fibres with whole g...

  10. The Coalition for Plasma Science: Bringing Plasmas to the Public

    Science.gov (United States)

    Berry, Lee

    2003-10-01

    The Coalition for Plasma Science is a group of institutions, organizations, and companies that have joined forces to increase awareness and understanding of plasma science and its many applications and benefits for society. The CPS undertakes a range of activities to support this goal. Members include national laboratories, universities, industries, and individuals. The CPS maintains a web page (http://www.plasmacoalition.org), and has developed several types of plasma-related publications. The web page includes a compilation of evaluated plasma web sites. The evaluations were conducted by teachers and based on national teaching standards. The web site also contains copies of CPS publications including the brochure ''Plasmas are Everywhere.'' Thousands of these brochures are distributed each year, and a poster version is now available. Another publication is the ''About Plasmas'' series. Each of these two-page papers (which is written for a general audience) is about a specific plasma-related topic, such as lighting, fusion, space plasmas and plasma decontamination of biological hazards. Papers on other topics are under development. The CPS also organizes educational luncheon/seminars for Members of Congress and their staff. The most recent seminar was given by David Newman on January 28th of this year and was his ''state of the universe'' address. A second seminar is planned this year on the topic of semiconductor manufacturing. Activities under discussion include a topical science fair award for a project on plasmas and the development of a broad, history-based educational web site.

  11. Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 357: Mud Pits and Waste Dump, Nevada Test Site, Nevada: Revision 0, Including Record of Technical Change No. 1

    Energy Technology Data Exchange (ETDEWEB)

    None

    2003-06-25

    This Streamlined Approach for Environmental Restoration (SAFER) plan was prepared as a characterization and closure report for Corrective Action Unit (CAU) 357, Mud Pits and Waste Dump, in accordance with the Federal Facility Agreement and Consent Order. The CAU consists of 14 Corrective Action Sites (CASs) located in Areas 1, 4, 7, 8, 10, and 25 of the Nevada Test Site (NTS). All of the CASs are found within Yucca Flat except CAS 25-15-01 (Waste Dump). Corrective Action Site 25-15-01 is found in Area 25 in Jackass Flat. Of the 14 CASs in CAU 357, 11 are mud pits, suspected mud pits, or mud processing-related sites, which are by-products of drilling activities in support of the underground nuclear weapons testing done on the NTS. Of the remaining CASs, one CAS is a waste dump, one CAS contains scattered lead bricks, and one CAS has a building associated with Project 31.2. All 14 of the CASs are inactive and abandoned. Clean closure with no further action of CAU 357 will be completed if no contaminants are detected above preliminary action levels. A closure report will be prepared and submitted to the Nevada Division of Environmental Protection for review and approval upon completion of the field activities. Record of Technical Change No. 1 is dated 3/2004.

  12. A Novel Genetic Approach to Investigate the Role of Plasma Secretory Phospholipase A2 (sPLA2)-V Isoenzyme in Coronary Heart Disease: A Modified Mendelian Randomization Analysis Using PLA2G5 Expression Levels

    Science.gov (United States)

    Holmes, Michael V.; Exeter, Holly J.; Folkersen, Lasse; Nelson, Christopher P.; Guardiola, Montse; Cooper, Jackie A.; Sofat, Reecha; Boekholdt, S. Matthijs; Kay-Tee-Khaw; Li, Ka-Wah; Smith, Andrew J. P.; Hooft, Ferdinand van’t; Eriksson, Per; Franco-Cereceda, Anders; Asselbergs, Folkert W.; Boer, Jolanda M. A.; Onland-Moret, N. Charlotte; Hofker, Marten; Erdmann, Jeanette; Kivimaki, Mika; Kumari, Meena; Reiner, Alex P.; Keating, Brendan J.; Humphries, Steve E.; Hingorani, Aroon D.; Mallat, Ziad; Samani, Nilesh J.; Talmud, Philippa J.

    2014-01-01

    Background Secretory phospholipase A2 (sPLA2) enzymes are considered to play a role in atherosclerosis. sPLA2 activity encompasses several sPLA2 isoenzymes, including sPLA2-V. While observational studies show strong association between elevated sPLA2 activity and CHD, no assay to measure sPLA2-V levels exists and the only evidence linking the sPLA2-V isoform to atherosclerosis progression comes from animal studies. In the absence of an assay that directly quantifies sPLA2-V levels, we used PLA2G5 mRNA levels in a novel, modified Mendelian randomization approach to investigate the hypothesized causal role of sPLA2-V in coronary heart disease (CHD) pathogenesis. Methods and Results Using data from the Advanced Study of Aortic Pathology, we identified the single nucleotide polymorphism (SNP) in PLA2G5 showing strongest association with PLA2G5 mRNA expression levels, as a proxy for sPLA2-V levels. We tested the association of this SNP with sPLA2 activity and CHD events in four prospective and 14 case-control studies with 27,230 events and 70,500 controls. rs525380C>A showed the strongest association with PLA2G5 mRNA expression (P=5.1×10−6). There was no association of rs525380C>A with plasma sPLA2 activity (difference in geometric mean of sPLA2 activity per rs525380 A-allele 0.4% (95%CI: −0.9%, 1.6%), P=0.56). In meta-analyses, the odds ratio for CHD per A allele was 1.02 (95% CI: 0.99, 1.04; P=0.20). Conclusions This novel approach for SNP selection for this modified Mendelian randomization analysis showed no association between rs525380 (the lead SNP for PLA2G5 expression, a surrogate for sPLA2-V levels) and CHD events. The evidence does not support a causal role for sPLA2-V in CHD. PMID:24563418

  13. Waves and instabilities in plasmas

    CERN Document Server

    Chen Liu

    1987-01-01

    The topics covered in these notes are selective and tend to emphasize more on kinetic-theory approaches to waves and instabilities in both uniform and non-uniform plasmas, students are assumed to have some basic knowledge of plasma dynamics in terms of single-particle and fluid descriptions.

  14. Ambipolar diffusion in plasma

    International Nuclear Information System (INIS)

    Is this thesis, a numerical method for the solution of the linear diffusion equation for a plasma containing two types of ions, with the possibility of charge exchange, has been developed. It has been shown that the decay time of the electron and ion densities is much smaller than that in a plasma containing only a single type of ion. A non-linear diffusion equation, which includes the effects of an external electric field varying linearly in time, to describe a slightly ionized plasma has also been developed. It has been verified that the decay of the electron density in the presence of such an electric field is very slow. (author)

  15. INTEGRATED PLASMA CONTROL FOR ADVANCED TOKAMAKS

    Energy Technology Data Exchange (ETDEWEB)

    HUMPHREYS,D.A; FERRON,J.R; JOHNSON,R.D; LEUER,J.A; PENAFLOR,B.G; WALKER,M.L; WELANDER,A.S; KHAYRUTDINOV,R.R; DOKOUKA,V; EDGELL,D.H; FRANSSON,C.M

    2003-10-01

    OAK-B135 Advanced tokamaks (AT) are distinguished from conventional tokamaks by their high degree of shaping, achievement of profiles optimized for high confinement and stability characteristics, and active stabilization of MHD instabilities to attain high values of normalized beta and confinement. These high performance fusion devices thus require accurate regulation of the plasma boundary, internal profiles, pumping, fueling, and heating, as well as simultaneous and well-coordinated MHD control action to stabilize such instabilities as tearing modes and resistive wall modes. Satisfying the simultaneous demands on control accuracy, reliability, and performance for all of these subsystems requires a high degree of integration in both design and operation of the plasma control system in an advanced tokamak. The present work describes the approach, benefits, and progress made in integrated plasma control with application examples drawn from the DIII-D tokamak. The approach includes construction of plasma and system response models, validation of models against operating experiments, design of integrated controllers which operate in concert with one another as well as with supervisory modules, simulation of control action against off-line and actual machine control platforms, and iteration of the design-test loop to optimize performance.

  16. Experimental Plasma Research project summaries

    International Nuclear Information System (INIS)

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report

  17. Experimental plasma research project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1978-08-01

    This report contans descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Measurements and Instrumentation; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  18. Experimental Plasma Research project summaries

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  19. Waves and Oscillations in Plasmas

    CERN Document Server

    Pecseli, Hans L

    2012-01-01

    The result of more than 15 years of lectures in plasma sciences presented at universities in Denmark, Norway, and the United States, Waves and Oscillations in Plasmas addresses central issues in modern plasma sciences. The book covers fluid models as well as kinetic plasma models, including a detailed discussion of, for instance, collisionless Landau damping. Offering a clear separation of linear and nonlinear models, the book can be tailored for readers of varying levels of expertise.Designed to provide basic training in linear as well as nonlinear plasma dynamics, and practical in areas as d

  20. Magnetized Plasma Experiments Using Thermionic- Thermoelectronic Plasma Emitter

    Science.gov (United States)

    Kawamori, Eiichirou; Cheng, C. Z.; Fujikawa, Nobuko; Lee, Jyun-Yi; Peng, Albert

    2008-11-01

    We are developing a magnetic mirror device, which is the first magnetized plasma device in Taiwan, to explore basic plasma sciences relevant to fusion, space and astrophysical plasmas. Our research subjects include electromagnetically induced transparency (EIT), Alfven wave physics, and plasma turbulence. A large diameter (> 200 mm) plasma emitter1, which utilizes thermionic- thermoelectronic emission from a mixture of LaB6 (Lanthanum-hexaboride) and beta-eucryptite (lithium type aluminosylicate) powders, is employed as a plasma source because of its production ability of fully ionized plasma and controllability of plasma emission rate. The plasma emitter has been installed recently and investigation of its characteristics will be started. The employment of beta-eucryptite in plasma emitter is the first experimental test because such investigation of beta-eucryptite has previously been used only for Li+-ion source2. Our plan for magnetized plasma experiments and results of the plasma emitter investigation will be presented. 1. K. Saeki, S. Iizuka, N. Sato, and Y. Hatta, Appl. Phys. Lett., 37, 1980, pp. 37-38. 2. M. Ueda, R. R. Silva, R. M. Oliveira, H. Iguchi, J. Fujita and K. Kadota, J. Phys. D: Appl. Phys. 30 1997, pp. 2711--2716.

  1. Plasma cell leukemia

    OpenAIRE

    Gertz, Moria A.; Buadi, Francis K.

    2010-01-01

    Plasma cell leukemia (PCL) is a rare, yet aggressive plasma cell (PC) neoplasm, variant of multiple myeloma (MM), characterized by high levels of PCs circulating in the peripheral blood. PCL can either originate de novo (primary PCL) or as a secondary leukemic transformation of MM (secondary PCL). Presenting signs and symptoms are similar to those seen in MM such as renal insufficiency, hypercalcemia, lytic bone lesions, anemia, and thrombocytopenia, but can also include hepatomegaly and sple...

  2. Color Instabilities in the Quark-Gluon Plasma

    CERN Document Server

    Mrowczynski, Stanislaw; Strickland, Michael

    2016-01-01

    When the quark-gluon plasma (QGP) - a system of deconfined quarks and gluons - is in a nonequilibrium state, it is usually unstable with respect to color collective modes. The instabilities, which are expected to strongly influence dynamics of the QGP produced in relativistic heavy-ion collisions, are extensively discussed under the assumption that the plasma is weakly coupled. We begin by presenting the theoretical approaches to study the QGP, which include: field theory methods based on the Keldysh-Schwinger formalism, classical and kinetic theories, and fluid techniques. The dispersion equations, which give the spectrum of plasma collective excitations, are analyzed in detail. Particular attention is paid to a momentum distribution of plasma constituents which is obtained by deforming an isotropic momentum distribution. Mechanisms of chromoelectric and chromomagnetic instabilities are explained in terms of elementary physics. The Nyquist analysis, which allows one to determine the number of solutions of a ...

  3. A New Neural Network Approach Including First-Guess for Retrieval of Atmospheric Water Vapor, Cloud Liquid Water Path, Surface Temperature and Emissivities Over Land From Satellite Microwave Observations

    Science.gov (United States)

    Aires, F.; Prigent, C.; Rossow, W. B.; Rothstein, M.; Hansen, James E. (Technical Monitor)

    2000-01-01

    The analysis of microwave observations over land to determine atmospheric and surface parameters is still limited due to the complexity of the inverse problem. Neural network techniques have already proved successful as the basis of efficient retrieval methods for non-linear cases, however, first-guess estimates, which are used in variational methods to avoid problems of solution non-uniqueness or other forms of solution irregularity, have up to now not been used with neural network methods. In this study, a neural network approach is developed that uses a first-guess. Conceptual bridges are established between the neural network and variational methods. The new neural method retrieves the surface skin temperature, the integrated water vapor content, the cloud liquid water path and the microwave surface emissivities between 19 and 85 GHz over land from SSM/I observations. The retrieval, in parallel, of all these quantities improves the results for consistency reasons. A data base to train the neural network is calculated with a radiative transfer model and a a global collection of coincident surface and atmospheric parameters extracted from the National Center for Environmental Prediction reanalysis, from the International Satellite Cloud Climatology Project data and from microwave emissivity atlases previously calculated. The results of the neural network inversion are very encouraging. The r.m.s. error of the surface temperature retrieval over the globe is 1.3 K in clear sky conditions and 1.6 K in cloudy scenes. Water vapor is retrieved with a r.m.s. error of 3.8 kg/sq m in clear conditions and 4.9 kg/sq m in cloudy situations. The r.m.s. error in cloud liquid water path is 0.08 kg/sq m . The surface emissivities are retrieved with an accuracy of better than 0.008 in clear conditions and 0.010 in cloudy conditions. Microwave land surface temperature retrieval presents a very attractive complement to the infrared estimates in cloudy areas: time record of land

  4. Plasma physics

    CERN Document Server

    Drummond, James E

    2013-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  5. Plasma undulator

    International Nuclear Information System (INIS)

    Two types of the undulator which is developed as a generator of the highly brilliant light for the synchrotron radiation sources and the free electron lasers, are newly proposed using the array of slender plasmas columns. One is the magnetic field type, in which the undulator force on the relativistic electron beam is generated with the electric current flowing through the plasma columns. The other is the electric field type, in which the undulator force is generated with the periodic variation of the density between the slender plasma columns. The production methods and stabilization ones of plasma columns are discussed. (author)

  6. A New Approach to Plasma CVD of TiO2 Photocatalyst on γ-Al2O3 Pellet Filled in Dielectric Barrier Discharges at Atmospheric Pressure

    Institute of Scientific and Technical Information of China (English)

    朱爱民; 聂龙辉; 张秀玲; 石川; 宋志民; 徐勇

    2004-01-01

    A supported TiO2/γ-Al2O3 photocatalyst has been prepared by γ-Al2O3 pellet-filled dielectric barrier discharges induced plasma CVD at atmospheric pressure and room temperature.The TiO2/γ-Al2O3 photocatalyst exhibits higher photocatalytic activity than Degussa P25, and much higher photocatalytic activity than that prepared by thermal CVD.

  7. Liquid chromatography-inductively coupled plasma-based metallomic approaches to probe health-relevant interactions between xenobiotics and mammalian organisms.

    Science.gov (United States)

    Gómez-Ariza, José Luis; Jahromi, Elham Zeini; González-Fernández, Macarena; García-Barrera, Tamara; Gailer, Jürgen

    2011-06-01

    In mammals, the transport of essential elements from the gastrointestinal tract to organs is orchestrated by biochemical mechanisms which have evolved over millions of years. The subsequent organ-based assembly of sufficient amounts of metalloproteins is a prerequisite to maintain mammalian health and well-being. The chronic exposure of various human populations to environmentally abundant toxic metals/metalloid compounds and/or the deliberate administration of medicinal drugs, however, can adversely affect these processes which may eventually result in disease. A better understanding of the perturbation of these processes has the potential to advance human health, but their visualization poses a major problem. Nonetheless, liquid chromatography-inductively coupled plasma-based 'metallomics' methods, however, can provide much needed insight. Size-exclusion chromatography-inductively coupled plasma atomic emission spectrometry, for example, can be used to visualize changes that toxic metals/medicinal drugs exert at the metalloprotein level when they are added to plasma in vitro. In addition, size-exclusion chromatography-inductively coupled plasma mass spectrometry can be employed to analyze organs from toxic metal/medicinal drug-exposed organisms for metalloproteins to gain insight into the biochemical changes that are associated with their acute or chronic toxicity. The execution of such studies-from the selection of an appropriate model organism to the generation of accurate analytical data-is littered with potential pitfalls that may result in artifacts. Drawing on recent lessons that were learned by two research groups, this tutorial review is intended to provide relevant information with regard to the experimental design and the practical application of these aforementioned metallomics tools in applied health research.

  8. Plasma Science Committee (PLSC)

    International Nuclear Information System (INIS)

    The Plasma Science Committee (PLSC) is a standing committee under the auspices of the Board on Physics and Astronomy, Commission on Physical Sciences, Mathematics, and Applications of the National Academy of Sciences--National Research Council. Plasma sciences represent a broad and diverse field. The PLSC has accepted the responsibility of monitoring the continuing development and assessing the general health of the field as whole. Although select advisory bodies have been created to address specific issues that affect plasma science, such as the Fusion Policy Advisory Committee (FPAC), the PLSC provides a focus for the plasma science community that is unique and essential. The membership of the PLSC is drawn from research laboratories in universities, industry, and government. Areas of expertise on the committee include accelerators and beams, space physics, astrophysics, computational physics and applied mathematics, fusion plasmas, fundamental experiments and theory, radiation sources, low temperature plasmas, and plasma-surface interactions. The PLSC is well prepared to respond to requests for studies on specific issues. This report discusses ion of the PLSC work

  9. Low temperature plasma technology methods and applications

    CERN Document Server

    Chu, Paul K

    2013-01-01

    Written by a team of pioneering scientists from around the world, Low Temperature Plasma Technology: Methods and Applications brings together recent technological advances and research in the rapidly growing field of low temperature plasmas. The book provides a comprehensive overview of related phenomena such as plasma bullets, plasma penetration into biofilms, discharge-mode transition of atmospheric pressure plasmas, and self-organization of microdischarges. It describes relevant technology and diagnostics, including nanosecond pulsed discharge, cavity ringdown spectroscopy, and laser-induce

  10. PLASMA DEVICE

    Science.gov (United States)

    Baker, W.R.

    1961-08-22

    A device is described for establishing and maintaining a high-energy, rotational plasma for use as a fast discharge capacitor. A disc-shaped, current- conducting plasma is formed in an axinl magnetic field and a crossed electric field, thereby creating rotational kinetic enengy in the plasma. Such energy stored in the rotation of the plasma disc is substantial and is convertible tc electrical energy by generator action in an output line electrically coupled to the plasma volume. Means are then provided for discharging the electrical energy into an external circuit coupled to the output line to produce a very large pulse having an extremely rapid rise time in the waveform thereof. (AE C)

  11. Plasmas generated in bubbles immersed in liquids: direct current streamers versus microwave plasma

    Science.gov (United States)

    Levko, Dmitry; Sharma, Ashish; Raja, Laxminarayan L.

    2016-07-01

    Two approaches to generate non-equilibrium atmospheric-pressure plasma in bubbles immersed in liquids are compared using high-fidelity 2D fluid simulations. In the first approach, corona/streamer like plasma is generated using high-voltage negative and positive pulses applied between two electrodes (pin-to-plane geometry) immersed in liquid. In the second, the plasma is generated using a remote microwave source (frequency 2.45 GHz). We find that the microwave approach requires less energy, while generating a denser, more chemically reactive and more uniform plasma within the bubble volume, as compared to the plasma generated using high-voltage pulsing.

  12. Modelling of new generation plasma optical devices

    Directory of Open Access Journals (Sweden)

    Litovko Irina V.

    2016-06-01

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

  13. Plasma physics for controlled fusion. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Kenro

    2016-08-01

    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator including quasi-symmetric system, open-end system of tandem mirror and inertial confinement are also explained. Newly added and updated topics in this second edition include zonal flows, various versions of H modes, and steady-state operations of tokamak, the design concept of ITER, the relaxation process of RFP, quasi-symmetric stellator, and tandem mirror. The book addresses graduate students and researchers in the field of controlled fusion.

  14. Plasma physics for controlled fusion. 2. ed.

    International Nuclear Information System (INIS)

    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator including quasi-symmetric system, open-end system of tandem mirror and inertial confinement are also explained. Newly added and updated topics in this second edition include zonal flows, various versions of H modes, and steady-state operations of tokamak, the design concept of ITER, the relaxation process of RFP, quasi-symmetric stellator, and tandem mirror. The book addresses graduate students and researchers in the field of controlled fusion.

  15. [Plasma properties: Annual report

    International Nuclear Information System (INIS)

    The Magneto-Fluid Dynamics Division of the Courant Institute is engaged in a broad program of basic research in the theoretical aspects of plasma physics and magneto-fluid dynamics with emphasis on those areas which are relevant to the fusion energy program. The total research program in the division includes efforts in the areas of plasma containment, stability, equilibrium, transport, wave propagation (including shock waves), heating, orbit theory, as well as numerical experiments and the development of practical numerical methods in all plasma problems. Applications are made to the following project areas: Tokamaks, Mirrors, Stellarators, and Alternate Concepts. Developments include the whole spectrum of models from macroscopic MHD and guiding center to Vlasov, drift kinetic Fokker-Planck, and Boltzmann. This document describes research completed as well as programs in progress

  16. Pseudopotential approach for dust acoustic solitary waves in dusty plasmas with kappa-distributed ions and electrons and dust grains having power law size distribution

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Gadadhar; Maitra, Sarit [Department of Mathematics, National Institute of Technology Durgapur, Durgapur (India)

    2015-04-15

    Sagdeev's pseudopotential method is used to study small as well as arbitrary amplitude dust acoustic solitons in a dusty plasma with kappa distributed electrons and ions with dust grains having power law size distribution. The existence of potential well solitons has been shown for suitable parametric region. The criterion for existence of soliton is derived in terms of upper and lower limit for Mach numbers. The numerical results show that the size distribution can affect the existence as well as the propagation characteristics of the dust acoustic solitons. The effect of kappa distribution is also highlighted.

  17. Electron-cyclotron plasma startup in the GDT experiment

    OpenAIRE

    Yakovlev, D. V.; Shalashov, A. G.; Gospodchikov, E. D.; Solomakhin, A. L.; Savkin, V. Ya.; Bagryansky, P.A.

    2016-01-01

    The paper reports on a new plasma startup scenario in the Gas Dynamic Trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target ("seed plasma"), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and bu...

  18. Validation of gyrokinetic modelling of light impurity transport including rotation in ASDEX Upgrade

    CERN Document Server

    Casson, F J; Angioni, C; Camenen, Y; Dux, R; Fable, E; Fischer, R; Geiger, B; Manas, P; Menchero, L; Tardini, G

    2013-01-01

    Upgraded spectroscopic hardware and an improved impurity concentration calculation allow accurate determination of boron density in the ASDEX Upgrade tokamak. A database of boron measurements is compared to quasilinear and nonlinear gyrokinetic simulations including Coriolis and centrifugal rotational effects over a range of H-mode plasma regimes. The peaking of the measured boron profiles shows a strong anti-correlation with the plasma rotation gradient, via a relationship explained and reproduced by the theory. It is demonstrated that the rotodiffusive impurity flux driven by the rotation gradient is required for the modelling to reproduce the hollow boron profiles at higher rotation gradients. The nonlinear simulations validate the quasilinear approach, and, with the addition of perpendicular flow shear, demonstrate that each symmetry breaking mechanism that causes momentum transport also couples to rotodiffusion. At lower rotation gradients, the parallel compressive convection is required to match the mos...

  19. Testing and assessment strategies, including alternative and new approaches.

    Science.gov (United States)

    Meyer, Otto

    2003-04-11

    The object of toxicological testing is to predict possible adverse effect in humans when exposed to chemicals whether used as industrial chemicals, pharmaceuticals or pesticides. Animal models are predominantly used in identifying potential hazards of chemicals. The use of laboratory animals raises ethical concern. However, irrespective of animal welfare it is an important aspect of the discipline of toxicology that the primary object is human health. The ideal testing and assessment strategy is simple to use all the available test methods and preferably more in laboratory animal species from which we get as many data as possible in order to obtain the most extensive database for the toxicological evaluation of a chemical. Consequently, the society has decided that certain group of chemicals should be tested accordingly. However, realising that, this idea is not obtainable in practice because there are more than 100000 chemicals which are potential for human exposure, so the development of alternative testing and assessment strategies has taken place in the recent years. The toxicological evaluation should enable the society to cope with the simultaneous requirement of many chemicals for different uses and of the absence of health problems involved with their use. Thus, the regulatory toxicology is a cocktail of science and pragmatism added a crucial concern for animal welfare. Test methods are most often used in a testing sequence as bricks in a testing strategy. The main key driving forces for introducing assessment and testing strategies e.g. using a limited number of tests and/or alternative test methods are: (a) animal welfare considerations; (b) new scientific knowledge i.e. introducing tests for new endpoints and tests for better understanding of mode of action; and (c) lack of testing capacity/reduction of required resources economically as well as time wise. PMID:12676447

  20. Tools for voltage stability analysis, including a probabilistic approach

    Energy Technology Data Exchange (ETDEWEB)

    Vieira Filho, X.; Martins, N.; Bianco, A.; Pinto, H.J.C.P. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Pereira, M.V.F. [Power System Research (PSR), Inc., Rio de Janeiro, RJ (Brazil); Gomes, P.; Santos, M.G. dos [ELETROBRAS, Rio de Janeiro, RJ (Brazil)

    1994-12-31

    This paper reviews some voltage stability analysis tools that are being used or envisioned for expansion and operational planning studies in the Brazilian system, as well as, their applications. The paper also shows that deterministic tools can be linked together in a probabilistic framework, so as to provide complementary help to the analyst in choosing the most adequate operation strategies, or the best planning solutions for a given system. (author) 43 refs., 8 figs., 8 tabs.

  1. Testing and assessment strategies, including alternative and new approaches

    DEFF Research Database (Denmark)

    Meyer, Otto A.

    2003-01-01

    The object of toxicological testing is to predict possible adverse effect in humans when exposed to chemicals whether used as industrial chemicals, pharmaceuticals or pesticides. Animal models are predominantly used in identifying potential hazards of chemicals. The use of laboratory animals raises...... ethical concern. However, irrespective of animal welfare it is an important aspect of the discipline of toxicology that the primary object is human health. The ideal testing and assessment strategy is simple to use all the available test methods and preferably more in laboratory animal species from which...... we get as many data as possible in order to obtain the most extensive database for the toxicological evaluation of a chemical. Consequently, the society has decided that certain group of chemicals should be tested accordingly. However, realising that, this idea is not obtainable in practice because...

  2. Including the public in pandemic planning: a deliberative approach

    Directory of Open Access Journals (Sweden)

    Braunack-Mayer Annette J

    2010-08-01

    Full Text Available Abstract Background Against a background of pandemic threat posed by SARS and avian H5N1 influenza, this study used deliberative forums to elucidate informed community perspectives on aspects of pandemic planning. Methods Two deliberative forums were carried out with members of the South Australian community. The forums were supported by a qualitative study with adults and youths, systematic reviews of the literature and the involvement of an extended group of academic experts and policy makers. The forum discussions were recorded with simultaneous transcription and analysed thematically. Results Participants allocated scarce resources of antiviral drugs and pandemic vaccine based on a desire to preserve society function in a time of crisis. Participants were divided on the acceptability of social distancing and quarantine measures. However, should such measures be adopted, they thought that reasonable financial, household and psychological support was essential. In addition, provided such support was present, the participants, in general, were willing to impose strict sanctions on those who violated quarantine and social distancing measures. Conclusions The recommendations from the forums suggest that the implementation of pandemic plans in a severe pandemic will be challenging, but not impossible. Implementation may be more successful if the public is engaged in pandemic planning before a pandemic, effective communication of key points is practiced before and during a pandemic and if judicious use is made of supportive measures to assist those in quarantine or affected by social isolation measures.

  3. Plasma-based radar cross section reduction

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents a comprehensive review of plasma-based stealth, covering the basics, methods, parametric analysis, and challenges towards the realization of the idea. The concealment of aircraft from radar sources, or stealth, is achieved through shaping, radar absorbing coatings, engineered materials, or plasma, etc. Plasma-based stealth is a radar cross section (RCS) reduction technique associated with the reflection and absorption of incident electromagnetic (EM) waves by the plasma layer surrounding the structure. A plasma cloud covering the aircraft may give rise to other signatures such as thermal, acoustic, infrared, or visual. Thus it is a matter of concern that the RCS reduction by plasma enhances its detectability due to other signatures. This needs a careful approach towards the plasma generation and its EM wave interaction. The book starts with the basics of EM wave interactions with plasma, briefly discuss the methods used to analyze the propagation characteristics of plasma, and its generatio...

  4. Fractal approach to surface roughness of TiO{sub 2}/WO{sub 3} coatings formed by plasma electrolytic oxidation process

    Energy Technology Data Exchange (ETDEWEB)

    Rožić, L.J., E-mail: ljrozic@nanosys.ihtmbg.ac.rs [University of Belgrade, IChTM-Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade (Serbia); Petrović, S.; Radić, N. [University of Belgrade, IChTM-Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade (Serbia); Stojadinović, S. [University of Belgrade, Faculty of Physics, Studentski trg 12-16, Belgrade (Serbia); Vasilić, R. [Faculty of Environmental Governance and Corporate Responsibility, Educons University, Vojvode Putnika 87, Sremska Kamenica (Serbia); Stefanov, P. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Sofia 1113 (Bulgaria); Grbić, B. [University of Belgrade, IChTM-Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade (Serbia)

    2013-07-31

    In this study, we have shown that atomic force microscopy is a powerful technique to study the fractal parameters of TiO{sub 2}/WO{sub 3} coatings prepared by plasma electrolytic oxidation (PEO) process. Since the surface roughness of obtained oxide coatings affects their physical properties, an accurate description of roughness parameters is highly desirable. The surface roughness, described by root mean squared and arithmetic average values, is analyzed considering the scans of a series of atomic force micrographs. The results show that the oxide coatings exhibit lower surface roughness in initial stage of PEO process. Also, the surfaces of TiO{sub 2}/WO{sub 3} coatings exhibit fractal behavior. Positive correlation between the fractal dimension and surface roughness of the surfaces of TiO{sub 2}/WO{sub 3} coatings in initial stage of PEO process was found. - Highlights: • TiO{sub 2}/WO{sub 3} coatings were obtained by plasma electrolytic oxidation. • Oxide coatings exhibit lower surface roughness in initial stage of process. • The surfaces of TiO{sub 2}/WO{sub 3} coatings exhibit fractal behavior.

  5. Keloid Management: A Retrospective Case Review on a New Approach Using Surgical Excision, Platelet-Rich Plasma, and In-office Superficial Photon X-ray Radiation Therapy

    Science.gov (United States)

    Jones, Michael E.; Hardy, Cherrell; Ridgway, Julie

    2016-01-01

    ABSTRACT OBJECTIVE: The objective of this retrospective study was to evaluate the efficacy of the authors’ combination therapy protocol for keloid treatment. DESIGN: Retrospective. SETTING: Plastic surgery office-based outpatient setting in New York City. PATIENTS: Forty patients with 44 keloid scars requiring surgical excision. INTERVENTIONS: Keloid scars were treated using surgical excision, platelet-rich plasma, and postoperative in-office superficial photon X-ray radiation therapy. Intralesional triamcinolone injections were administered once to 4 patients with poor results on scar scale assessment. Patient follow-up visits ranged from 3 to 11 months to assess for evidence of recurrence and adverse effects. MAIN OUTCOME MEASURE(S): For the purpose of this study, recurrence was defined as any sign of extraordinary erythema, induration, and hypertrophy beyond the site of excision. MAIN RESULTS: In the 16 keloids treated with 2 fractions, there was no evidence of recurrence. One of 25 keloids treated with 3 fractions demonstrated evidence of recurrence. One of 3 keloids treated with a single fraction displayed signs of recurrence. Postirradiation hyperpigmentation was noted in all patients. CONCLUSIONS: Surgical excision combined with platelet-rich plasma and postoperative in-office superficial radiation therapy achieved a 95.5% nonrecurrence rate at 1- to 3-month follow-up. This protocol appears to be a safe and viable option in the management of keloids and merits further randomized controlled study of its comparative efficacy. PMID:27300360

  6. Three-dimensional magnetic perturbation fields in fusion plasmas: plasma edge transport and plasma surface interaction

    International Nuclear Information System (INIS)

    Three-dimensional (3D) magnetic perturbation fields are applied to high temperature plasma experiments to optimize the transport in the plasma edge and the resulting plasma wall interaction. While 3D magnetic field topologies are inherent to stellarator devices, the application of small, external 3D magnetic perturbation fields is a new and promising approach in tokamaks to control cyclic edge instabilities causing impulsive heat and particle loads to the first wall. The external 3D field applied breaks the axisymmetry and the standard assumptions for plasma edge transport are not valid anymore. Thus the resulting plasma surface interaction is governed by the 3D field structure. This talk will survey experimental results on the formation of such a 3D plasma boundary and the stationary plasma edge transport is studied with a Monte-Carlo fluid plasma and kinetic neutral transport model (EMC3-Eirene) in direct comparison to the experiment. It is shown that a 3D plasma boundary is induced resulting in 3D plasma surface particle and heat fluxes. Experimental quantification of the resulting material erosion at the wall elements shows that the net-erosion characteristic in a 3D boundary is highly dependent on the actual location in the 3D topology.

  7. Plasma physics

    International Nuclear Information System (INIS)

    This report contains the papers delivered at the AEB - Natal University summer school on plasma physics held in Durban during January 1979. The following topics were discussed: Tokamak devices; MHD stability; trapped particles in tori; Tokamak results and experiments; operating regime of the AEB Tokamak; Tokamak equilibrium; high beta Tokamak equilibria; ideal Tokamak stability; resistive MHD instabilities; Tokamak diagnostics; Tokamak control and data acquisition; feedback control of Tokamaks; heating and refuelling; neutral beam injection; radio frequency heating; nonlinear drift wave induced plasma transport; toroidal plasma boundary layers; microinstabilities and injected beams and quasilinear theory of the ion acoustic instability

  8. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  9. Plasma technology

    International Nuclear Information System (INIS)

    IREQ was contracted by the Canadian Electrical Association to review plasma technology and assess the potential for application of this technology in Canada. A team of experts in the various aspects of this technology was assembled and each team member was asked to contribute to this report on the applications of plasma pertinent to his or her particular field of expertise. The following areas were examined in detail: iron, steel and strategic-metals production; surface treatment by spraying; welding and cutting; chemical processing; drying; and low-temperature treatment. A large market for the penetration of electricity has been identified. To build up confidence in the technology, support should be provided for selected R and D projects, plasma torch demonstrations at full power, and large-scale plasma process testing

  10. Linking plasma kinetics to plasma-bio interactions

    Science.gov (United States)

    Bruggeman, Peter

    2015-05-01

    Cold non-equilibrium atmospheric pressure plasmas have received a lot of attention in the last decade due to their huge potential for biomedical applications. In my group, we have characterized an RF driven APPJ in great detail. The characterization includes electrical measurements, imaging, optical emission spectroscopy, (two photon enhanced) laser induced fluorescence, Thomson scattering, Rayleigh scattering, Raman scattering and mass spectrometry. This led to a detailed knowledge of the electron density, electron temperature, gas temperature, NO, O, OH, O3 densities, ionic species and air concentrations in the plasma effluent. Living organisms for in vitro studies are typically kept in complex solutions or culture media. Plasma-bio interactions involves not only the production of reactive species in the plasma gas phase but also transport to the liquid phase and plasma induced liquid phase chemistry and its impact on the living organisms. Reactive nitrogen and oxygen species have been identified as the key reactive species. Recent results of my group show that controlling the gas phase plasma chemistry can lead to significant different biological responses of the living organisms corresponding to different chemical pathways. The effect of plasma jet interaction with liquids containing mammalian cells, bacteria and virus will be discussed. The outcomes of these studies allow unraveling chemical pathways responsible for plasma-bio interactions and linking plasma kinetics to plasma-bio interactions.

  11. Surface Modification of Nanometre Silicon Carbide Powder with Polystyrene by Inductively Coupled Plasma

    International Nuclear Information System (INIS)

    An investigation was made into polystyrene (PS) grafted onto nanometre silicon carbide (SiC) particles. In our experiment, the grafting polymerization reaction was induced by a radio frequency (RF) inductively coupled plasma (ICP) treatment of the nanometre powder. FTIR (Fourier transform infrared spectrum) and XPS (X-ray photoelectron spectroscopy) results reveal that PS is grafted onto the surface of silicon carbide powder. An analysis is presented on the effectiveness of this approach as a function of plasma operating variables including the plasma treating power, treating time, and grafting reaction temperature and time.

  12. Surface Modification of Nanometre Silicon Carbide Powder with Polystyrene by Inductively Coupled Plasma

    Science.gov (United States)

    Wei, Gang; Meng, Yuedong; Zhong, Shaofeng; Liu, Feng; Jiang, Zhongqing; Shu, Xingsheng; Ren, Zhaoxing; Wang, Xiangke

    2008-02-01

    An investigation was made into polystyrene (PS) grafted onto nanometre silicon carbide (SiC) particles. In our experiment, the grafting polymerization reaction was induced by a radio frequency (RF) inductively coupled plasma (ICP) treatment of the nanometre powder. FTIR (Fourier transform infrared spectrum) and XPS (X-ray photoelectron spectroscopy) results reveal that PS is grafted onto the surface of silicon carbide powder. An analysis is presented on the effectiveness of this approach as a function of plasma operating variables including the plasma treating power, treating time, and grafting reaction temperature and time.

  13. Surface Modification of Nanometre Silicon Carbide Powder with Polystyrene by Inductively Coupled Plasma

    Institute of Scientific and Technical Information of China (English)

    WEI Gang; MENG Yuedong; ZHONG Shaofeng; LIU Feng; JIANG Zhongqing; SHU Xingsheng; REN Zhaoxing; WANG Xiangke

    2008-01-01

    An investigation was made into polystyrene (PS) grafted onto nanometre sili-con carbide (SIC) particles. In our experiment, the grafting polymerization reaction was in-duced by a radio frequency (RF) inductively coupled plasma (ICP) treatment of the nanome-tre powder. FTIR (Fourier transform infrared spectrum) and XPS (X-ray photoelectron spec-troscopy) results reveal that PS is grafted onto the surface of silicon carbide powder. An analysis is presented on the effectiveness of this approach as a function of plasma operating variables including the plasma treating power, treating time, and grafting reaction temperature and time.

  14. Plasma Speaker

    OpenAIRE

    Kovář, J

    2015-01-01

    The article describes the design and construction of one-channel plasma speaker. Absence of mechanical membrane gives the plasma speaker no frequency limitation. The design consists of power source to supply control electronic for signal modulation, converter and output transformer. Modulation of audio signal is realized by integrated circuit TL 594 that provides the PWM modulation. Duty cycle and frequency is adjusted by potentiometers. Dual forward converter is used to voltage amplification...

  15. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  16. Nonaxisymmetric magnetorotational instability in ideal and viscous plasmas

    Science.gov (United States)

    Mikhailovskii, A. B.; Lominadze, J. G.; Galvão, R. M. O.; Churikov, A. P.; Erokhin, N. N.; Smolyakov, A. I.; Tsypin, V. S.

    2008-05-01

    The excitation of magnetorotational instability (MRI) in rotating laboratory plasmas is investigated. In contrast to astrophysical plasmas, in which gravitation plays an important role, in laboratory plasmas it can be neglected and the plasma rotation is equilibrated by the pressure gradient. The analysis is restricted to the simple model of a magnetic confinement configuration with cylindrical symmetry, in which nonaxisymmetric perturbations are investigated using the local approximation. Starting from the simplest case of an ideal plasma, the corresponding dispersion relations are derived for more complicated models including the physical effects of parallel and perpendicular viscosities. The Friemann-Rotenberg approach used for ideal plasmas is generalized for the viscous model and an analytical expression for the instability boundary is obtained. It is shown that, in addition to the standard effect of radial derivative of the rotation frequency (the Velikhov effect), which can be destabilizing or stabilizing depending on the sign of this derivative in the ideal plasma, there is a destabilizing effect proportional to the fourth power of the rotation frequency, or, what is the same, to the square of the plasma pressure gradient, and to the square of the azimuthal mode number of the perturbations. It is shown that the instability boundary also depends on the product of the plasma pressure and density gradients, which has a destabilizing effect when it is negative. In the case of parallel viscosity, the MRI looks like an ideal instability independent of viscosity, while, in the case of strong perpendicular viscosity, it is a dissipative instability with the growth rate inversely proportional to the characteristic viscous decay rate. We point out, however, that the modes of the continuous range of the magnetohydrodynamics spectrum are not taken into account in this paper, and they can be more dangerous than those that are considered.

  17. The 22nd AINSE plasma science and technology conference. Conference handbook

    International Nuclear Information System (INIS)

    These proceedings contain the extended abstracts of the papers and posters presented at the 22nd AINSE plasma science and technology conference hosted by the Australian National University in Canberra. Topics under discussion included: fusion devices and experiments; plasma production; plasma confinement; plasma heating and current drive; plasma waves; plasma diagnostics; basic collisionless plasma physics; laser produced plasmas and inertial confinement; low-temperature plasmas and interferometry. The individual papers were indexed separately

  18. Heavy quark bound states in a quark-gluon plasma: dissociation and recombination

    CERN Document Server

    Blaizot, Jean-Paul; Faccioli, Pietro; Garberoglio, Giovanni

    2015-01-01

    We present a comprehensive approach to the dynamics of heavy quarks in a quark gluon plasma, including the possibility of bound state formation and dissociation. In this exploratory paper, we restrict ourselves to the case of an Abelian plasma, but the extension of the techniques used to the non Abelian case is straightforward. A chain of well defined approximations leads eventually to a generalized Langevin equation, where the force and the noise terms are determined from a correlation function of the equilibrium plasma, and depend explicitly on the configuration of the heavy quarks. We solve the Langevin equation for various initial conditions, various numbers of heavy quark-antiquark pairs, and various temperatures of the plasma. Results of simulations illustrate various expected phenomena: dissociation of bound states as a result of combined effects of screening of the potential and collisions with the plasma constituent, formation of bound pairs (recombination) that occurs when enough heavy quarks are pr...

  19. Effective Potential Theory: A Practical Way to Extend Plasma Transport Theory to Strong Coupling

    CERN Document Server

    Baalrud, Scott D; Daligault, Jerome

    2014-01-01

    The effective potential theory is a physically motivated method for extending traditional plasma transport theories to stronger coupling. It is practical in the sense that it is easily incorporated within the framework of the Chapman-Enskog or Grad methods that are commonly applied in plasma physics and it is computationally efficient to evaluate. The extension is to treat binary scatterers as interacting through the potential of mean force, rather than the bare Coulomb or Debye-screened Coulomb potential. This allows for aspects of many-body correlations to be included in the transport coefficients. Recent work has shown that this method accurately extends plasma theory to orders of magnitude stronger coupling when applied to the classical one-component plasma model. The present work shows that similar accuracy is realized for the Yukawa one-component plasma model and it provides a comparison with other approaches.

  20. Plasma on a foundry cupola

    Science.gov (United States)

    Pineau, Didier

    An experiment of a plasma torch on a production foundry cupola is reported. The test runs were conducted on a hot blast cupola, the blast temperature in the absence of plasma being 400 C. With the torch, the temperature of the blast was increased to 1000 C. The experiment was conducted for the manufacture of car engines with a 2.5 MW transportable plasma system. The cupola was boosted with a 4 MW torch and results included an increase in production of 45 percent, a decrease in coke rate and no more new iron in the loads. The plasma torch and hot air cupola furnace are described.

  1. Formation of Imploding Plasma Liners for HEDP and MIF Application

    Energy Technology Data Exchange (ETDEWEB)

    Witherspoon, F. Douglas [HyperV Technologies Corp.; Case, Andrew [HyperV Technologies Corp.; Brockington, Samuel [HyperV Technologies Corp.y; Messer, Sarah [HyperV Technologies Corp.; Bomgardner, Richard [HyperV Technologies Corp.; Phillips, Mike [HyperV Technologies Corp.; Wu, Linchun [HyperV Technologies Corp.; Elton, Ray [University of Maryland

    2014-11-11

    Plasma jets with high density and velocity have a number of important applications in fusion energy and elsewhere, including plasma refueling, disruption mitigation in tokamaks, magnetized target fusion, injection of momentum into centrifugally confined mirrors, plasma thrusters, and high energy density plasmas (HEDP). In Magneto-Inertial Fusion (MIF), for example, an imploding material liner is used to compress a magnetized plasma to fusion conditions and to confine the resulting burning plasma inertially to obtain the necessary energy gain. The imploding shell may be solid, liquid, gaseous, or a combination of these states. The presence of the magnetic field in the target plasma suppresses thermal transport to the plasma shell, thus lowering the imploding power needed to compress the target to fusion conditions. This allows the required imploding momentum flux to be generated electromagnetically using off-the-shelf pulsed power technology. Practical schemes for standoff delivery of the imploding momentum flux are required and are open topics for research. One approach for accomplishing this, called plasma jet driven magneto-inertial fusion (PJMIF), uses a spherical array of pulsed plasma guns to create a spherically imploding shell of very high velocity, high momentum flux plasma. This approach requires development of plasma jet accelerators capable of achieving velocities of 50-200 km/s with very precise timing and density profiles, and with high total mass and density. Low-Z plasma jets would require the higher velocities, whereas very dense high-Z plasma shells could achieve the goal at velocities of only 50-100 km/s. In this report, we describe our work to develop the pulsed plasma gun technology needed for an experimental scientific exploration of the PJMIF concept, and also for the other applications mentioned earlier. The initial goal of a few hundred of hydrogen at 200 km/s was eventually replaced with accelerating 8000 μg of argon or xenon to 50 km

  2. Review: engineering particles using the aerosol-through-plasma method

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, Jonathan [Los Alamos National Laboratory; Luhrs, Claudia C [UNM; Richard, Monique [TEMA

    2009-01-01

    For decades, plasma processing of materials on the nanoscale has been an underlying enabling technology for many 'planar' technologies, particularly virtually every aspect of modern electronics from integrated-circuit fabrication with nanoscale elements to the newest generation of photovoltaics. However, it is only recent developments that suggest that plasma processing can be used to make 'particulate' structures of value in fields, including catalysis, drug delivery, imaging, higher energy density batteries, and other forms of energy storage. In this paper, the development of the science and technology of one class of plasma production of particulates, namely, aerosol-through-plasma (A-T-P), is reviewed. Various plasma systems, particularly RF and microwave, have been used to create nanoparticles of metals and ceramics, as well as supported metal catalysts. Gradually, the complexity of the nanoparticles, and concomitantly their potential value, has increased. First, unique two-layer particles were generated. These were postprocessed to create unique three-layer nanoscale particles. Also, the technique has been successfully employed to make other high-value materials, including carbon nanotubes, unsupported graphene, and spherical boron nitride. Some interesting plasma science has also emerged from efforts to characterize and map aerosol-containing plasmas. For example, it is clear that even a very low concentration of particles dramatically changes plasma characteristics. Some have also argued that the local-thermodynamic-equilibrium approach is inappropriate to these systems. Instead, it has been suggested that charged- and neutral-species models must be independently developed and allowed to 'interact' only in generation terms.

  3. Fundamentals of plasma physics

    CERN Document Server

    Bittencourt, J A

    1986-01-01

    A general introduction designed to present a comprehensive, logical and unified treatment of the fundamentals of plasma physics based on statistical kinetic theory. Its clarity and completeness make it suitable for self-learning and self-paced courses. Problems are included.

  4. Laser Plasmas : Optical guiding of laser beam in nonuniform plasma

    Indian Academy of Sciences (India)

    Tarsem Singh Gill

    2000-11-01

    A plasma channel produced by a short ionising laser pulse is axially nonuniform resulting from the self-defocusing. Through such preformed plasma channel, when a delayed pulse propagates, the phenomena of diffraction, refraction and self-phase modulation come into play. We have solved the nonlinear parabolic partial differential equation governing the propagation characteristics for an approximate analytical solution using variational approach. Results are compared with the theoretical model of Liu and Tripathi (Phys. Plasmas 1, 3100 (1994)) based on paraxial ray approximation. Particular emphasis is on both beam width and longitudinal phase delay which are crucial to many applications.

  5. Formation of Imploding Plasma Liners for HEDP and MIF Application

    Energy Technology Data Exchange (ETDEWEB)

    Witherspoon, F. Douglas [HyperV Technologies Corp.; Case, Andrew [HyperV Technologies Corp.; Brockington, Samuel [HyperV Technologies Corp.y; Messer, Sarah [HyperV Technologies Corp.; Bomgardner, Richard [HyperV Technologies Corp.; Phillips, Mike [HyperV Technologies Corp.; Wu, Linchun [HyperV Technologies Corp.; Elton, Ray [University of Maryland

    2014-11-11

    Plasma jets with high density and velocity have a number of important applications in fusion energy and elsewhere, including plasma refueling, disruption mitigation in tokamaks, magnetized target fusion, injection of momentum into centrifugally confined mirrors, plasma thrusters, and high energy density plasmas (HEDP). In Magneto-Inertial Fusion (MIF), for example, an imploding material liner is used to compress a magnetized plasma to fusion conditions and to confine the resulting burning plasma inertially to obtain the necessary energy gain. The imploding shell may be solid, liquid, gaseous, or a combination of these states. The presence of the magnetic field in the target plasma suppresses thermal transport to the plasma shell, thus lowering the imploding power needed to compress the target to fusion conditions. This allows the required imploding momentum flux to be generated electromagnetically using off-the-shelf pulsed power technology. Practical schemes for standoff delivery of the imploding momentum flux are required and are open topics for research. One approach for accomplishing this, called plasma jet driven magneto-inertial fusion (PJMIF), uses a spherical array of pulsed plasma guns to create a spherically imploding shell of very high velocity, high momentum flux plasma. This approach requires development of plasma jet accelerators capable of achieving velocities of 50-200 km/s with very precise timing and density profiles, and with high total mass and density. Low-Z plasma jets would require the higher velocities, whereas very dense high-Z plasma shells could achieve the goal at velocities of only 50-100 km/s. In this report, we describe our work to develop the pulsed plasma gun technology needed for an experimental scientific exploration of the PJMIF concept, and also for the other applications mentioned earlier. The initial goal of a few hundred of hydrogen at 200 km/s was eventually replaced with accelerating 8000 μg of argon or xenon to 50 km

  6. Plasma metallization

    CERN Document Server

    Crowther, J M

    1997-01-01

    Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of s...

  7. Is Almond Consumption More Effective Than Reduced Dietary Saturated Fat at Decreasing Plasma Total Cholesterol and LDL-c Levels? A Theoretical Approach

    Directory of Open Access Journals (Sweden)

    Rudy M. Ortiz

    2012-01-01

    Full Text Available Hypercholesterolemia can be a consequence of excessive dietary saturated fatty acid (SFA, while almond-supplemented diets can improve lipid profiles. However, the differential and independent impacts of dietary SFA and almondsupplemented diets on plasma total cholesterol (pTC and low-density lipoprotein (pLDL-c concentrations have not been directly compared and are not well described. We reviewed the available data to construct multiple regression analyses to theoretically assess the impact of relative almond intake (RAI and dietary SFA on reducing pTC and pLDL-c concentrations. Strong, negative correlations between RAI and percent change in mean pTC (R=0.776;P=0.005 and RAI and percent change in mean pLDL-c (R=0.818;P=0.002 were detected. The relationships between percent change in mean dietary SFA, and percent change in mean pTC and mean pLDL-c were weaker and only significant for pLDL-c. The multiple regression analyses demonstrated modest improvements in the strength of the correlations for both pTC (R=0.804;P=0.016 and pLDL-c (R=0.855;P=0.005. The models suggest that the increase in RAI contributes to the reduction in pTC and pLDL-c to a greater extent than a reduction in dietary SFA, but a simultaneous decrease in dietary SFA should further improve lipid profiles.

  8. Experimental plasma research project summaries

    International Nuclear Information System (INIS)

    This is the latest in a series of Project Summary books going back to 1976 and is the first after a hiatus of several years. They are published to provide a short description of each project supported by the Experimental Plasma Research Branch of the Division of Applied Plasma Physics in the Office of Fusion Energy. The Experimental Plasma Research Branch seeks to provide a broad range of experimental data, physics understanding, and new experimental techniques that contribute to operation, interpretation, and improvement of high temperature plasma as a source of fusion energy. In pursuit of these objectives, the branch supports research at universities, DOE laboratories, other federal laboratories and industry. About 70 percent of the funds expended are spent at universities and a significant function of this program is the training of students in fusion physics. The branch supports small- and medium-scale experimental studies directly related to specific critical plasma issues of the magnetic fusion program. Plasma physics experiments are conducted on transport of particles and energy within plasma and innovative approaches for operating, controlling, and heating plasma are evaluated for application to the larger confinement devices of the magnetic fusion program. New diagnostic approaches to measuring the properties of high temperature plasmas are developed to the point where they can be applied with confidence on the large-scale confinement experiments. Atomic data necessary for impurity control, interpretation of diagnostic data, development of heating devices, and analysis of cooling by impurity ion radiation are obtained. The project summaries are grouped into these three categories of plasma physics, diagnostic development and atomic physics

  9. Plasma Beat-Wave Acceleration

    Science.gov (United States)

    Clayton, Christopher E.

    2002-04-01

    Among all the advanced accelerator concepts that use lasers as the power source, most of the effort to date has been with the idea of using a laser pulse to excite a accelerating mode in a plasma. Within this area, there are a variety of approaches for creating the accelerating mode, as indicated by the other talks in this session. What is common to these approaches is the physics of how a laser pulse pushes on plasma electrons to organize electron-density perturbations, the sources of the ultra-high (> GeV/M) accelerating gradients. It is the "ponderomotive force", proportional to the local gradient of the of the laser intensity, that pushes plasma electrons forward (on the leading edge of the pulse) and backwards (on the trailing edge) which leads to harmonic motion of the electrons. As the laser pulse moves through the plasma at group velocity Vg c, the oscillating electrons show up macroscopically as a plasma mode or wave with frequency w equal to the plasma frequency and k = w/Vg. For short laser pulses, this is the Laser Wakefield Accelerator (LWFA) concept. Closely related is the Plasma Beat-Wave Acceleration (PBWA) concept. Here, the laser pulse that perturbs the plasma is composed of two closely-spaced frequencies that "beat", i.e., periodically constructively and destructively interfere, forming an electromagnetic beat wave. One can visualize this as a train of short pulses. If this beating frequency is set to the plasma frequency, then each pulse in the train will reinforce the density perturbation caused by the previous pulse. The principal advantage of multiple pulses driving up the plasma wave as opposed to a single pulse is in efficiency, allowing for the production of relatively large diameter (more 1-D like) accelerating modes. In this talk I will discuss past, current and planned PBWA experiments which are taking place at UCLA, RAL in England, and LULI in France.

  10. Haplotype-based approach for noninvasive prenatal tests of Duchenne muscular dystrophy using cell-free fetal DNA in maternal plasma

    DEFF Research Database (Denmark)

    Xu, Yan; Li, Xuchao; Ge, Hui-Juan;

    2015-01-01

    Purpose:This study demonstrates noninvasive prenatal testing (NIPT) for Duchenne muscular dystrophy (DMD) using a newly developed haplotype-based approach.Methods:Eight families at risk for DMD were recruited for this study. Parental haplotypes were constructed using target-region sequencing data....... With a mean depth of 30× achieved in the 10-Mb target region of each sample, the noninvasive results were consistent with those of the invasive procedure.Conclusion:This is the first report of NIPT for DMD and the first application of a haplotype-based approach in NIPT for X-linked diseases. With further...... improvements in accuracy, this haplotype-based strategy could be feasible for NIPT for DMD and even other X-linked single-gene disorders.Genet Med advance online publication 05 February 2015Genetics in Medicine (2015); doi:10.1038/gim.2014.207....

  11. Plasma dynamo

    CERN Document Server

    Rincon, F; Schekochihin, A A; Valentini, F

    2015-01-01

    Magnetic fields pervade the entire Universe and, through their dynamical interactions with matter, affect the formation and evolution of astrophysical systems from cosmological to planetary scales. How primordial cosmological seed fields arose and were further amplified to $\\mu$Gauss levels reported in nearby galaxy clusters, near equipartition with kinetic energy of plasma motions and on scales of at least tens of kiloparsecs, is a major theoretical puzzle still largely unconstrained by observations. Extragalactic plasmas are weakly collisional (as opposed to collisional magnetohydrodynamic fluids), and whether magnetic-field growth and its sustainment through an efficient dynamo instability driven by chaotic motions is possible in such plasmas is not known. Fully kinetic numerical simulations of the Vlasov equation in a six-dimensional phase space necessary to answer this question have until recently remained beyond computational capabilities. Here, we show by means of such simulations that magnetic-field a...

  12. Laser beam-plasma coupling in laser solenoid plasmas

    International Nuclear Information System (INIS)

    A model has been constructed to analyze the gross beam-plasma interaction in a laser solenoid plasma. The model includes a simple solution for a slab plasma response to a given laser beam, and a solution for axial beam size variations in response to arbitrary axial plasma structure. The two solutions are combined to determine the coupled behavior. Trapping of the focused laser beam where it enters the plasma is a significant problem, but can be achieved by a minimum level of imbedded field in the plasma. If the beam is trapped, it first focuses and then defocuses near the front of the bleaching wave (front of the laser heated plasma). In order to avoid divergence of the beam near the front, it is essential to have a pre-formed favorable density profile in the plasma. Such a condition is probably achieved automatically in the early stages of plasma heating. Several techniques are discussed which can be used to avert unfavorable refractive behavior (catastrophic self-focusing and defocusing)

  13. Plasma properties

    International Nuclear Information System (INIS)

    A cursory examination of the research activities of the Magneto-Fluid Dynamics Division for the calendar year 1988 shows the effects of the gradual transformation of the group. Although our principal activity, fusion plasma physics research, is unchanged, the work shows closer ties to problems relevant to present experiments than previously. Most notable is the concentrated effort on tokamak equilibrium and transport. We are exploring the implication of turbulence induced transport, resistive MHD effects, neoclassical transport, and possible interpretations of transport based on classical phenomena. In addition, one of our members has chosen to focus on problems of enhanced statistical methods for interpretation of experiments. All of this activity preceded the Tokamak Transport Initiative and reflects our active involvement and concern with the world-wide tokamak program. Since equilibrium and transport are by no means the only theoretical plasma physics problems affecting fusion devices we continue substantial efforts in wave propagation and heating, particle simulation of plasmas, stability theory, enhancement of numerical algorithms, and general plasma physics. We are attempting to develop effective numerical schemes for the Boltzmann equation, adaptive grid methods for MHD, and particle simulation of boundary and antenna effects. Many of these topics reflect our continuing concern to maintain a modest effort in the development of theoretical models and tools for problems of real significance to fusion, but not necessarily of immediate highest priority. We select problems which we expect to become extremely important in the future. Our space plasma physics activities, funded by agencies other than DOE, transfers knowledge learned in fusion plasma physics to another area and conversely stimulates work also relevant to fusion problems

  14. Plasma physics and controlled nuclear fusion

    International Nuclear Information System (INIS)

    The report contains the proceedings of a conference on plasma physics. A fraction of topics included MHD instabilities, magnetic confinement and plasma heating in the field of fusion plasmas, in 8 papers falling in the INIS scope have been abstracted and indexed for the INIS database. (K.A.)

  15. ''Dusty plasmas''

    International Nuclear Information System (INIS)

    The field of ''dusty plasmas'' promises to be a very rewarding topic of research for the next decade or so, not only from the academic point of view where the emphasis is on developing the theory of the often complex collective and non-linear processes, but also from the point of view of applications in astrophysics, space physics, environmental and energy research. In this ''comment'' we should like to sketch the current development of this fast growing and potentially very important research area. We will discuss the new features of ''dusty'' plasmas in the most general terms and then briefly mention some successful applications and effects which have already been examined. (author)

  16. Atmospheric pressure plasma for surface modification

    CERN Document Server

    Wolf, Rory A

    2012-01-01

    This Book's focus and intent is to impart an understanding of the practical application of atmospheric plasma for the advancement of a wide range of current and emerging technologies. The primary key feature of this book is the introduction of over thirteen years of practical experimental evidence of successful surface modifications by atmospheric plasma methods. It offers a handbook-based approach for leveraging and optimizing atmospheric plasma technologies which are currently in commercial use. It also offers a complete treatment of both basic plasma physics and industrial plasma process

  17. Neutrino oscillations in a turbulent plasma

    Energy Technology Data Exchange (ETDEWEB)

    Mendonça, J. T. [Instituto de Física, Universidade de São Paulo, São Paulo, SP, CEP 05508-090 Brazil and IPFN, Instituto Superior Técnico, 1049-001 Lisboa (Portugal); Haas, F. [Departamento de Física, Universidade Federal do Paraná, Curitiba PR, CEP 81531-990 (Brazil)

    2013-07-15

    A new model for the joint neutrino flavor and plasma oscillations is introduced, in terms of the dynamics of the neutrino flavor polarization vector in a plasma background. Fundamental solutions are found for both time-invariant and time-dependent media, considering slow and fast variations of the electron plasma density. The model is shown to be described by a generalized Hamiltonian formalism. In the case of a broad spectrum of electron plasma waves, a statistical approach indicates the shift of both equilibrium value and frequency oscillation of flavor coherence, due to the existence of a turbulent plasma background.

  18. Potential cellular targets and antibacterial efficacy of atmospheric pressure non-thermal plasma.

    Science.gov (United States)

    Alkawareek, Mahmoud Y; Gorman, Sean P; Graham, William G; Gilmore, Brendan F

    2014-02-01

    Atmospheric pressure non-thermal plasma (APNTP) has been gaining increasing interest as a new alternative antibacterial approach. Although this approach has demonstrated promising antibacterial activity, its exact mechanism of action remains unclear. Mechanistic elucidation of the antimicrobial activity will facilitate development and rational optimisation of this approach for potential medical applications. In this study, the antibacterial efficacy of an in-house-built APNTP jet was evaluated alongside an investigation of the interactions between APNTP and major cellular components in order to identify the potential cellular targets involved in plasma-mediated bacterial destruction mechanisms. The investigated plasma jet exhibited excellent, rapid antibacterial activity against a selected panel of clinically significant bacterial species including Bacillus cereus, meticillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and Pseudomonas aeruginosa, all of which were completely inactivated within 2 min of plasma exposure. Plasma-mediated damaging effects were observed, to varying degrees, on all of the investigated cellular components including DNA, a model protein enzyme, and lipid membrane integrity and permeability. The antibacterial efficacy of APNTP appears to involve a multiple-target mechanism, which potentially reduces the likelihood of emergence of microbial resistance towards this promising antimicrobial approach. However, cellular membrane damage and resulting permeability perturbation was found to be the most likely rate-determining step in this mechanism.

  19. Anomalous transport in toroidal plasmas

    International Nuclear Information System (INIS)

    When the magnetic moment of particle is conserved, there are three mechanisms which cause anomalous transport. These are: variation of magnetic field strength in flux surface, variation of electrostatic potential in flux surface, and destruction of flux surface. The anomalous transport of different groups of particles resulting from each of these mechanisms is different. This fact can be exploited to determine the cause of transport operative in an experimental situation. This approach can give far more information on the transport than the standard confinement time measurements. To implement this approach, we have developed Monte Carlo codes for toroidal geometries. The equations of motion are developed in a set of non-canonical, practical Boozer co-ordinates by means of Jacobian transformations of the particle drift Hamiltonian equations of motion. Effects of collisions are included by appropriate stochastic changes in the constants of motion. Effects of the loop voltage on particle motions are also included. We plan to apply our method to study two problems: the problem of the hot electron tail observed in edge region of ZT-40, and the energy confinement time in TOKAPOLE II. For the ZT-40 problem three situations will be considered: a single mode in the core, a stochastic region that covers half the minor radius, a stochastic region that covers the entire plasma. A turbulent spectrum of perturbations based on the experimental data of TOKAPOLE II will be developed. This will be used to simulate electron transport resulting from ideal instabilities and resistive instabilities in TOKAPOLE II

  20. Plasma physics and engineering

    CERN Document Server

    Fridman, Alexander

    2011-01-01

    Part I: Fundamentals of Plasma Physics and Plasma ChemistryPlasma in Nature, in the Laboratory, and in IndustryOccurrence of Plasma: Natural and Man MadeGas DischargesPlasma Applications, Plasmas in IndustryPlasma Applications for Environmental ControlPlasma Applications in Energy ConversionPlasma Application for Material ProcessingBreakthrough Plasma Applications in Modern TechnologyElementary Processes of Charged Species in PlasmaElementary Charged Particles in Plasma and Their Elastic and Inelastic CollisionsIonization ProcessesMechanisms of Electron Losses: The Electron-Ion RecombinationEl

  1. Hall Effect in a Plasma.

    Science.gov (United States)

    Kunkel, W. B.

    1981-01-01

    Describes an apparatus and procedure for conducting an undergraduate laboratory experiment to quantitatively study the Hall effect in a plasma. Includes background information on the Hall effect and rationale for conducting the experiment. (JN)

  2. Nuclear excitation in plasma

    International Nuclear Information System (INIS)

    4 main electromagnetic excitation processes of atomic nuclei in hot dense plasma are reviewed: the black body photon absorption, the electron inelastic scattering, the nuclear excitation by electron capture (NEEC effect) and the nuclear excitation by electron transition (NEET effect). Experimental results on Ta181m are commented and an experiment showing the NEEC effect on Fe57 is described. A model including all the phenomena of excitation and de-excitation of a nuclear state in plasma, has been developed. Predictions about the evolution of the life-time of a nuclear excited state as a function of the temperature and density are made. A complete calculation of the NEET effect of the first excited state of U235 in a local thermodynamic equilibrium plasma is presented. Some experimental works on the excitation of U235m in a laser-produced plasma are discussed. The NEET effect on Hg201 in a laser-produced plasma is also considered in both theoretical and experimental aspects

  3. Plasma Simulation Program

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a

  4. Evolution of the mirror approach to fusion: some conjectures

    Energy Technology Data Exchange (ETDEWEB)

    Post, R.E.

    1984-09-18

    Some possible directions for the future evolution of the mirror approach to fusion are outlined, in the context of economically-motivated criteria. Speculations are given as to the potential advantages, economic and otherwise, of the use of axially-symmetric systems, operated in semi-collisional regimes of lower Q (fusion power balance ratio) than that projected for present-day tandem mirror designs. These regims include barely tandem modes, and ion-heated modes, in association with higher efficiency direct conversion. Another possible economically advantageous approach mentioned is the use of a tandem mirror plasma to stabilize a FRM (field-reversed mirror) plasma, with potential synergistic advantages.

  5. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    Energy Technology Data Exchange (ETDEWEB)

    Witherspoon, F. Douglas [HyperV Technologies Corp.; Welch, Dale R. [Voss Scientific, LLC; Thompson, John R. [FAR-TECH, Inc.; MacFarlane, Joeseph J. [Prism Computational Sciences Inc.; Phillips, Michael W. [Advanced Energy Systems, Inc.; Bruner, Nicki [Voss Scientific, LLC; Mostrom, Chris [Voss Scientific, LLC; Thoma, Carsten [Voss Scientific, LLC; Clark, R. E. [Voss Scientific, LLC; Bogatu, Nick [FAR-TECH, Inc.; Kim, Jin-Soo [FAR-TECH, Inc.; Galkin, Sergei [FAR-TECH, Inc.; Golovkin, Igor E. [Prism Computational Sciences, Inc.; Woodruff, P. R. [Prism Computational Sciences, Inc.; Wu, Linchun [HyperV Technologies Corp.; Messer, Sarah J. [HyperV Technologies Corp.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism

  6. Gas Plasma Surface Chemistry for Biological Assays.

    Science.gov (United States)

    Sahagian, Khoren; Larner, Mikki

    2015-01-01

    Biological systems respond to and interact with surfaces. Gas plasma provides a scalable surface treatment method for designing interactive surfaces. There are many commercial examples of plasma-modified products. These include well plates, filtration membranes, dispensing tools, and medical devices. This chapter presents an overview of gas plasma technology and provides a guide to using gas plasma for modifying surfaces for research or product development. PMID:26160577

  7. Atomic physics and radiation processes in plasmas

    International Nuclear Information System (INIS)

    It is pointed out that atomic and molecular (A/M) processes play important roles in divertor plasmas but the problems related to these processes are not yet studied quantitatively. Recently new subjects related to A/M processes such as plasma- vapor interaction during plasma disruption are presented. This is a brief summary of our discussions. Our recent results of the calculations for the line emissions of carbon atoms in edge plasmas are also included. (J.P.N.)

  8. Gas Plasma Surface Chemistry for Biological Assays.

    Science.gov (United States)

    Sahagian, Khoren; Larner, Mikki

    2015-01-01

    Biological systems respond to and interact with surfaces. Gas plasma provides a scalable surface treatment method for designing interactive surfaces. There are many commercial examples of plasma-modified products. These include well plates, filtration membranes, dispensing tools, and medical devices. This chapter presents an overview of gas plasma technology and provides a guide to using gas plasma for modifying surfaces for research or product development.

  9. PLASMA SPECTROSCOPY

    NARCIS (Netherlands)

    Jaspers, R. J. E.

    2010-01-01

    A brief introduction into the spectroscopy of fusion plasmas is presented. Basic principles of the emission of ionic, atomic and molecular radiation is explained and a survey of the effects, which lead to the population of the respective excited levels, is given. Line radiation, continuum radiation,

  10. Spectroscopic studies of microwave plasmas containing hexamethyldisiloxane

    Science.gov (United States)

    Nave, A. S. C.; Mitschker, F.; Awakowicz, P.; Röpcke, J.

    2016-10-01

    Low-pressure microwave discharges containing hexamethyldisiloxane (HMDSO) with admixtures of oxygen and nitrogen, used for the deposition of silicon containing films, have been studied spectroscopically. Optical emission spectroscopy (OES) in the visible spectral range has been combined with infrared laser absorption spectroscopy (IRLAS). The experiments were carried out in order to analyze the dependence of plasma chemical phenomena on power and gas mixture at relatively low pressures, up to 50 Pa, and power values, up to 2 kW. The evolution of the concentration of the methyl radical, CH3, and of seven stable molecules, HMDSO, CH4, C2H2, C2H4, C2H6, CO and CO2, was monitored in the plasma processes by in situ IRLAS using tunable lead salt diode lasers (TDL) and external-cavity quantum cascade lasers (EC-QCL) as radiation sources. To achieve reliable values for the gas temperature inside and outside the plasma bulk as well as for the temperature in the plasma hot and colder zones, which are of great importance for calculation of species concentrations, three different methods based on emission and absorption spectroscopy data of N2, CH3 and CO have been used. In this approach line profile analysis has been combined with spectral simulation methods. The concentrations of the various species, which were found to be in the range between 1011 to 1015 cm-3, are in the focus of interest. The influence of the discharge parameters power, pressure and gas mixture on the molecular concentrations has been studied. To achieve further insight into general plasma chemical aspects the dissociation of the HMDSO precursor gas including its fragmentation and conversion to the reaction products was analyzed in detail.

  11. Rapid quick, easy, cheap, effective, rugged, and safe extraction with novel phospholipid cleanup: A streamlined ultra high performance liquid chromatography with ultraviolet detection approach for screening polycyclic aromatic hydrocarbons in avian blood cells and plasma.

    Science.gov (United States)

    Provatas, Anthony A; Yevdokimov, Alexander V; King, Cory A; Gatley, Emma L; Stuart, James D; Evers, David C; Perkins, Christopher R

    2015-08-01

    A streamlined method has been developed for the isolation and analysis of polycyclic aromatic hydrocarbons in avian blood cells and plasma utilizing quick, easy, cheap, effective, rugged, and safe extraction in combination with novel phospholipid cleanup technology. A variety of traditional extraction and cleanup techniques have been employed in the preparation and analysis of polycyclic aromatic hydrocarbonsin a variety of matrices; liquid-liquid partitioning, solid-phase extractions, gel permeation chromatography, and column chromatography are all effective techniques, however they are laborious and time consuming processes that require large amounts of solvent. Using quick, easy, cheap, effective, rugged, and safe extraction coupled with phospholipid cleanup, samples can be quickly screened while maintaining high throughput and sensitivity. With a liquid chromatography approach, analysis times may be kept short at 16 min while maintaining high analyte recovery. Recoveries in quality control samples ranged from 70 to 109%, with average surrogate recoveries of 80.6 ± 1.10%. The result of using a quick, easy, cheap, effective, rugged, and safe extraction approach in conjunction with phospholipid cleanup is a methodology that significantly reduces sample preparation time and solvent use while maintaining high sensitivity and reproducibility.

  12. Including heavy flavour production in PDF fits

    OpenAIRE

    A.M. Cooper-Sarkar

    2007-01-01

    AT HERA heavy quarks may contribute up to 30% of the structure function $F_2$. The introduction of heavy quarks requires an extension of the DGLAP formalism. The effect of using different heavy flavour number schemes, and different approaches to the running of $\\alpha_s$, are compared using the ZEUS PDF fit formalism. The potential of including charm data in the fit is explored, using $D^*$ double differential cross-sections rather than the inclusive quantity $F_2^{c\\bar{c}}$.

  13. Magnetoresistive waves in plasmas

    International Nuclear Information System (INIS)

    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed

  14. Theory including future not excluded

    DEFF Research Database (Denmark)

    Nagao, K.; Nielsen, H.B.

    2013-01-01

    , Ehrenfest's theorem, and the conserved probability current density. In addition,we showthat the expectation value at the present time t of a future-included theory for large T - t and large t - T corresponds to that of a future-not-included theory with a proper inner product for large t - T. Hence, the CAT......We study a complex action theory (CAT) whose path runs over not only past but also future. We show that, if we regard a matrix element defined in terms of the future state at time T and the past state at time TA as an expectation value in the CAT, then we are allowed to have the Heisenberg equation...

  15. Biodiversity conservation including uncharismatic species

    DEFF Research Database (Denmark)

    Muñoz, Joaquin

    2007-01-01

    Recent papers mention ideas on the topics of biodiversity conservation strategies and priorities (Redford et al. 2003; Lamoreux et al. 2006; Rodrı´guez et al. 2006), the current status of biodiversity (Loreau et al. 2006), the obligations of conservation biologists regarding management policies...... (Chapron 2006; Schwartz 2006), and the main threats to biodiversity (including invasive species) (Bawa 2006). I suggest, however, that these articles do not really deal with biodiversity. Rather, they all focus on a few obviously charismatic groups (mammals, birds, some plants, fishes, human culture...

  16. Plasmas Granulares

    OpenAIRE

    Conde López, Luis; Donoso Vargas, Jose Manuel; Sánchez Torres, Antonio; Tkachenko, Igor Mijail; Cal, Eduardo de la; Carralero Ortiz, Daniel; Pablos, José Luis

    2011-01-01

    Los plasmas granulares son gases total o parcialmente ionizados que, además de iones electrones y átomos neutros, contienen partículas sólidas con carga eléctrica. Dichas partículas cargadas, de tamaño mesoscópico, dan lugar a nuevos fenómenos colectivos con una dinámica característica. Este tipo de plasmas aparecen en sistemas físicos tan diversos como son los reactores de fusión por confinamiento magnético, los sistemas de procesado de semiconductores o en medios astrofísicos. Se presenta u...

  17. Kinetics and spectroscopy of low temperature plasmas

    CERN Document Server

    Loureiro, Jorge

    2016-01-01

    This is a comprehensive textbook designed for graduate and advanced undergraduate students. Both authors rely on more than 20 years of teaching experience in renowned Physics Engineering courses to write this book addressing the students’ needs. Kinetics and Spectroscopy of Low Temperature Plasmas derives in a full self-consistent way the electron kinetic theory used to describe low temperature plasmas created in the laboratory with an electrical discharge, and presents the main optical spectroscopic diagnostics used to characterize such plasmas. The chapters with the theoretical contents make use of a deductive approach in which the electron kinetic theory applied to plasmas with basis on the electron Boltzmann equation is derived from the basic concepts of Statistical and Plasma Physics. On the other hand, the main optical spectroscopy diagnostics used to characterize experimentally such plasmas are presented and justified from the point of view of the Atomic and Molecular Physics. Low temperature plasmas...

  18. Plasma lenses for focusing particle beams

    International Nuclear Information System (INIS)

    The focusing of particles by a thin plasma lens is analyzed with physical, linearized fluid and particle-in-cell computational models. For parameters similar to next-generation linear colliders, the plasma lens strength can exceed 100 MG/cm, and the luminosity can be enhanced by an order of magnitude by passing each beam through an appropriate plasma slab. The plasma electrons affect the focusing by shifting so as to (partially or completely) charge neutralize the beam. Both overdense and underdense plasma lenses are described (plasma density n0 greater or less than beam density nb). The former case applies equally well to e+ and e- beams, while the latter has distinct advantages for e- beams (including smaller aberrations and background). The effects of spherical and longitudinal aberrations, emittance, plasma boundaries, and non-linear-plasma dynamics on the final spot size are discussed

  19. Merging of high speed argon plasma jets

    Energy Technology Data Exchange (ETDEWEB)

    Case, A.; Messer, S.; Brockington, S.; Wu, L.; Witherspoon, F. D. [HyperV Technologies Corp., Chantilly, Virginia 22180 (United States); Elton, R. [University of Maryland, College Park, Maryland 20742 (United States)

    2013-01-15

    Formation of an imploding plasma liner for the plasma liner experiment (PLX) requires individual plasma jets to merge into a quasi-spherical shell of plasma converging on the origin. Understanding dynamics of the merging process requires knowledge of the plasma phenomena involved. We present results from the study of the merging of three plasma jets in three dimensional geometry. The experiments were performed using HyperV Technologies Corp. 1 cm Minirailguns with a preionized argon plasma armature. The vacuum chamber partially reproduces the port geometry of the PLX chamber. Diagnostics include fast imaging, spectroscopy, interferometry, fast pressure probes, B-dot probes, and high speed spatially resolved photodiodes, permitting measurements of plasma density, temperature, velocity, stagnation pressure, magnetic field, and density gradients. These experimental results are compared with simulation results from the LSP 3D hybrid PIC code.

  20. Plasma diagnostics by means of electric probes

    International Nuclear Information System (INIS)

    In this work a summary of the classical theoretical models to interpret the characteristic curve of a Langmuir electric probe placed in a plasma without magnetic field and with the one is made. The methodology for the electron temperature calculation and the density of the plasma in both cases is given, starting from the characteristic curve of the probe, as well as the approaches for the correct application of this diagnostic method of the plasma. (Author)

  1. Helium generated cold plasma finely regulates activation of human fibroblast-like primary cells.

    Directory of Open Access Journals (Sweden)

    Paola Brun

    Full Text Available Non-thermal atmospheric pressure plasmas are being developed for a wide range of health care applications, including wound healing. However in order to exploit the potential of plasma for clinical applications, the understanding of the mechanisms involved in plasma-induced activation of fibroblasts, the cells active in the healing process, is mandatory. In this study, the role of helium generated plasma in the tissue repairing process was investigated in cultured human fibroblast-like primary cells, and specifically in hepatic stellate cells and intestinal subepithelial myofibroblasts. Five minutes after treatment, plasma induced formation of reactive oxygen species (ROS in cultured cells, as assessed by flow cytometric analysis of fluorescence-activated 2',7'-dichlorofluorescein diacetate probe. Plasma-induced intracellular ROS were characterized by lower concentrations and shorter half-lives with respect to hydrogen peroxide-induced ROS. Moreover ROS generated by plasma treatment increased the expression of peroxisome proliferator activated receptor (PPAR-γ, nuclear receptor that modulates the inflammatory responses. Plasma exposure promoted wound healing in an in vitro model and induced fibroblast migration and proliferation, as demonstrated, respectively, by trans-well assay and partitioning between daughter cells of carboxyfluorescein diacetate succinimidyl ester fluorescent dye. Plasma-induced fibroblast migration and proliferation were found to be ROS-dependent as cellular incubation with antioxidant agents (e.g. N-acetyl L-cysteine cancelled the biological effects. This study provides evidence that helium generated plasma promotes proliferation and migration in liver and intestinal fibroblast-like primary cells mainly by increasing intracellular ROS levels. Since plasma-evoked ROS are time-restricted and elicit the PPAR-γ anti-inflammatory molecular pathway, this strategy ensures precise regulation of human fibroblast activation and

  2. Plasma medicine: an introductory review

    Science.gov (United States)

    Kong, M. G.; Kroesen, G.; Morfill, G.; Nosenko, T.; Shimizu, T.; van Dijk, J.; Zimmermann, J. L.

    2009-11-01

    This introductory review on plasma health care is intended to provide the interested reader with a summary of the current status of this emerging field, its scope, and its broad interdisciplinary approach, ranging from plasma physics, chemistry and technology, to microbiology, biochemistry, biophysics, medicine and hygiene. Apart from the basic plasma processes and the restrictions and requirements set by international health standards, the review focuses on plasma interaction with prokaryotic cells (bacteria), eukaryotic cells (mammalian cells), cell membranes, DNA etc. In so doing, some of the unfamiliar terminology—an unavoidable by-product of interdisciplinary research—is covered and explained. Plasma health care may provide a fast and efficient new path for effective hospital (and other public buildings) hygiene—helping to prevent and contain diseases that are continuously gaining ground as resistance of pathogens to antibiotics grows. The delivery of medically active 'substances' at the molecular or ionic level is another exciting topic of research through effects on cell walls (permeabilization), cell excitation (paracrine action) and the introduction of reactive species into cell cytoplasm. Electric fields, charging of surfaces, current flows etc can also affect tissue in a controlled way. The field is young and hopes are high. It is fitting to cover the beginnings in New Journal of Physics, since it is the physics (and non-equilibrium chemistry) of room temperature atmospheric pressure plasmas that have made this development of plasma health care possible.

  3. Plasma medicine: an introductory review

    International Nuclear Information System (INIS)

    This introductory review on plasma health care is intended to provide the interested reader with a summary of the current status of this emerging field, its scope, and its broad interdisciplinary approach, ranging from plasma physics, chemistry and technology, to microbiology, biochemistry, biophysics, medicine and hygiene. Apart from the basic plasma processes and the restrictions and requirements set by international health standards, the review focuses on plasma interaction with prokaryotic cells (bacteria), eukaryotic cells (mammalian cells), cell membranes, DNA etc. In so doing, some of the unfamiliar terminology-an unavoidable by-product of interdisciplinary research-is covered and explained. Plasma health care may provide a fast and efficient new path for effective hospital (and other public buildings) hygiene-helping to prevent and contain diseases that are continuously gaining ground as resistance of pathogens to antibiotics grows. The delivery of medically active 'substances' at the molecular or ionic level is another exciting topic of research through effects on cell walls (permeabilization), cell excitation (paracrine action) and the introduction of reactive species into cell cytoplasm. Electric fields, charging of surfaces, current flows etc can also affect tissue in a controlled way. The field is young and hopes are high. It is fitting to cover the beginnings in New Journal of Physics, since it is the physics (and non-equilibrium chemistry) of room temperature atmospheric pressure plasmas that have made this development of plasma health care possible.

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

    Institute of Scientific and Technical Information of China (English)

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

    2012-01-01

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

  5. Range of fractionated plasma products to optimize plasma resources

    Institute of Scientific and Technical Information of China (English)

    Thierry Burnouf

    2010-01-01

    @@ HUMAN PLASMA is a source material that is crucial for the production of unique therapeutic fractionated products. Indeed, plasma contains hundreds of proteins ensuring many physiological functions. The most abun-dant proteins, albumin and immunoglobulin G (IgG) ,are present at about 35 and 10 g/L,respectively,repre-senting about 80% of all plasma proteins. However,other important therapeutic proteins include the coagu-lation factors (factor Ⅷ (F Ⅷ) ; FIX ; Von Willebrand Factor (VWF), fibrinogen) various protease inhibitors (alpha 1-antitrypsin ; antithrombin; C1-esterase) and anticoagulants (protein C) which exhibit potent physi-ological activity.

  6. Plasma diagnostics of non-equilibrium atmospheric plasma jets

    Science.gov (United States)

    Shashurin, Alexey; Scott, David; Keidar, Michael; Shneider, Mikhail

    2014-10-01

    Intensive development and biomedical application of non-equilibrium atmospheric plasma jet (NEAPJ) facilitates rapid growth of the plasma medicine field. The NEAPJ facility utilized at the George Washington University (GWU) demonstrated efficacy for treatment of various cancer types (lung, bladder, breast, head, neck, brain and skin). In this work we review recent advances of the research conducted at GWU concerned with the development of NEAPJ diagnostics including Rayleigh Microwave Scattering setup, method of streamer scattering on DC potential, Rogowski coils, ICCD camera and optical emission spectroscopy. These tools allow conducting temporally-resolved measurements of plasma density, electrical potential, charge and size of the streamer head, electrical currents flowing though the jet, ionization front propagation speed etc. Transient dynamics of plasma and discharge parameters will be considered and physical processes involved in the discharge will be analyzed including streamer breakdown, electrical coupling of the streamer tip with discharge electrodes, factors determining NEAPJ length, cross-sectional shape and propagation path etc.

  7. Plasma fluoride and enamel fluorosis.

    Science.gov (United States)

    Angmar-Månsson, B; Ericsson, Y; Ekberg, O

    1976-11-24

    It is postulated that tissue fluid F concentrations are the primary determinants of flouride effects on bones and developing teeth and that these concentrations are dependent on, or mirrored by, blood plasma F. It has earlier been shown that the plasma F levels are dependent on the dietary F supply as well as on skeletal F concentration. Fasting and post-ingestion or postinjection plasma F levels have been determined in rats on F doses that cause different degrees of enamel fluorosis. The results indicate that temporary peak values rather than elevated fasting values are responsible for the occurrence of enamel fluorosis and that the peak values must approach about 10 muM in order to block enamel formation by the ameloblasts. The diagnostic and prognostic importance of plasma F determinations is discussed.

  8. Families classification including multiopposition asteroids

    Science.gov (United States)

    Milani, Andrea; Spoto, Federica; Knežević, Zoran; Novaković, Bojan; Tsirvoulis, Georgios

    2016-01-01

    In this paper we present the results of our new classification of asteroid families, upgraded by using catalog with > 500,000 asteroids. We discuss the outcome of the most recent update of the family list and of their membership. We found enough evidence to perform 9 mergers of the previously independent families. By introducing an improved method of estimation of the expected family growth in the less populous regions (e.g. at high inclination) we were able to reliably decide on rejection of one tiny group as a probable statistical fluke. Thus we reduced our current list to 115 families. We also present newly determined ages for 6 families, including complex 135 and 221, improving also our understanding of the dynamical vs. collisional families relationship. We conclude with some recommendations for the future work and for the family name problem.

  9. Plasma chemistry study of PLAD processes

    Energy Technology Data Exchange (ETDEWEB)

    Qin Shu; Brumfield, Kyle; Liu, Lequn Jennifer; Hu, Yongjun Jeff; McTeer, Allen; Hsu, Wei Hui; Wang Maoying [Nanya Technology Inc., Santa Clara, CA 95054 (United States); Micron Technology Inc., Boise, ID 83707 (United States)

    2012-11-06

    Plasma doping (PLAD) shows very different impurity profiles compared to the conventional beam-line-based ion implantations due to its non-mass separation property and plasma environment. There is no simulation for PLAD process so far due to a lack of a dopant profile model. Several factors determine impurity profiles of PLAD process. The most significant factors are: plasma chemistry and deposition/etching characteristics of multi-ion species plasmas. In this paper, we present plasma chemistry and deposition/etching characteristics of PLAD processes versus co-gas dilutions. Four dopant plasmas including B{sub 2}H{sub 6}, BF{sub 3}, AsH{sub 3}, and PH{sub 3}, and two non-dopant plasmas including CH{sub 4} and GeH{sub 4} are studied and demonstrated.

  10. Time resolved two- and three-dimensional plasma diagnostics

    International Nuclear Information System (INIS)

    This collection of papers on diagnostics in fusion plasmas contains work on the data analysis of inverse problems and on the experimental arrangements presently used to obtain spatially and temporally resolved plasma radial profiles, including electron and ion temperature, plasma density and plasma current profiles. Refs, figs and tabs

  11. Special issue on transient plasmas

    Science.gov (United States)

    Bailey, James; Hoarty, David; Mancini, Roberto; Yoneda, Hitoki

    2015-11-01

    This special issue of Journal of Physics B: Atomic, Molecular and Optical Physics is dedicated to the "spectroscopy of transient plasmas" covering plasma conditions produced by a range of pulsed laboratory sources including short and long pulse lasers, pulsed power devices, and free electron lasers (FELs). The full range of plasma spectroscopy up to high energy bremsstrahlung radiation, including line broadening analysis for application to data recorded with the ChemCam instrument on the Mars Science Laboratory rover Curiosity, is covered. This issue is timely as advances in optical lasers and x-ray FELs (XFEL) are enabling transient plasma to be probed at higher energies and shorter durations than ever before. New XFEL facilities being commissioned in Europe and Asia are adding to those operating in the US and Japan and the ELI high power laser project in Europe, due to open this year, will provide short pulse lasers of unprecedented power. This special issue represents a snapshot of the theoretical and experimental research in dense plasmas, electron kinetics, laser-induced breakdown spectroscopy of low temperature plasmas, inertial confinement fusion and non-equilibrium atomic physics using spectroscopy to diagnose plasmas produced by optical lasers, XFELs and pulsed-power machines.

  12. Relativistic spherical plasma waves

    CERN Document Server

    Bulanov, S S; Schroeder, C B; Zhidkov, A G; Esarey, E; Leemans, W P

    2011-01-01

    Tightly focused laser pulses as they diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we report on theoretical study of relativistic spherical wake waves and their properties, including wave breaking. These waves may be suitable as particle injectors or as flying mirrors that both reflect and focus radiation, enabling unique X-ray sources and nonlinear QED phenomena.

  13. Hydrodynamic theory of diffusion in two-temperature multicomponent plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ramshaw, J.D.; Chang, C.H. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-12-31

    Detailed numerical simulations of multicomponent plasmas require tractable expressions for species diffusion fluxes, which must be consistent with the given plasma current density J{sub q} to preserve local charge neutrality. The common situation in which J{sub q} = 0 is referred to as ambipolar diffusion. The use of formal kinetic theory in this context leads to results of formidable complexity. We derive simple tractable approximations for the diffusion fluxes in two-temperature multicomponent plasmas by means of a generalization of the hydrodynamical approach used by Maxwell, Stefan, Furry, and Williams. The resulting diffusion fluxes obey generalized Stefan-Maxwell equations that contain driving forces corresponding to ordinary, forced, pressure, and thermal diffusion. The ordinary diffusion fluxes are driven by gradients in pressure fractions rather than mole fractions. Simplifications due to the small electron mass are systematically exploited and lead to a general expression for the ambipolar electric field in the limit of infinite electrical conductivity. We present a self-consistent effective binary diffusion approximation for the diffusion fluxes. This approximation is well suited to numerical implementation and is currently in use in our LAVA computer code for simulating multicomponent thermal plasmas. Applications to date include a successful simulation of demixing effects in an argon-helium plasma jet, for which selected computational results are presented. Generalizations of the diffusion theory to finite electrical conductivity and nonzero magnetic field are currently in progress.

  14. The role of anomalous resistivities in Plasma Focus discharges

    International Nuclear Information System (INIS)

    The existence of plasma microturbulence in Plasma Focus (PF) devices is a widely accepted fact within the PF community. This microturbulence must be generated as a final stage of microscopic instabilities, which could develop during certain phases of the plasma evolution. Among the candidate instabilities to occur in these devices, the lower hybrid drift instability is the one with better possibilities, because its triggering condition (electron drift velocity approaching ion thermal velocity) has reasonable chances to be fulfilled. The main effect of the development of this instability is the modification of the collision frequencies in the plasma, which adds an anomalous term to the plasma resistivity. The theory for evaluating this extra term exists, and has been already used in PF 1D numerical simulations and in Z-pinch calculations. The role of this anomalous resistivity in PF behaviour has been the subject of considerable speculations. In this work, a 1D MHD (magnetohydrodynamics) calculation of the pinch stage in a PF device will be presented, including anomalous resistivity effects and their influence on electric fields and the discharge current are discussed. (author)

  15. Modelling of large-scale microwave plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, C M; Tatarova, E; Henriques, J; Dias, F M [Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal)

    2009-10-07

    Theoretical models have been developed for large-scale microwave discharges driven by surface waves which account in a self-consistent way for the main plasma balances, including bulk and surface elementary processes, as well as wave electrodynamics. The systems under consideration are long tubular and large-volume, slot-antenna excited plasma sources. As an example of application, discharges in N{sub 2}-Ar mixtures, which are characterized by a complex kinetics, are analysed in some detail. The approach used describes self-consistently the spatial structure of the plasma sources, i.e. the spatial distribution of population densities of excited species, charged particles and ground-state molecules and atoms taking into account the main energy exchange pathways as well as plasma-wall interactions. The model predictions are shown to compare well with experiment in the case of both sources. It is demonstrated that the self-consistent models developed provide deep physical insight into the discharge workings, being also instrumental as a tool for the optimization of these plasma sources in view of specific applications.

  16. Stark broadening data for stellar plasma research.

    Science.gov (United States)

    Dimitrijević, M. S.

    Results of an effort to provide to astrophysicists and physicists an as much as possible complete set of Stark broadening parameters needed for stellar opacity calculations, stellar atmosphere modelling, abundance determinations and diagnostics of different plasmas in astrophysics, physics and plasma technology, are presented. Stark broadening has been considered within the semiclassical perturbation, and the modified semiempirical approaches.

  17. Space plasma physics: I - Stationary processes

    Science.gov (United States)

    Hasegawa, Akira; Sato, Tetsuya

    1989-01-01

    The physics of stationary processes in space plasmas is examined theoretically in an introduction intended for graduate students. The approach involves the extensive use of numerical simulations. Chapters are devoted to fundamental principles, small-amplitude waves, and the stationary solar plasma system; typical measurement data and simulation results are presented graphically.

  18. Plasma-materials interactions

    International Nuclear Information System (INIS)

    Over the past year, plasma edge diagnostics for the Advanced Toroidal Facility were identified, and the design of hardware was initiated. These diagnostics are being prepared to study plasma density and temperature, particle and heat fluxes, impurity production and transport, and the configuration of the edge plasma. The conceptual design of top and bottom rail limiters, configured as calorimeter arrays, was finished, and detailed engineering design is under way. In collaboration with Japan and the Federal Republic of Germany, the PMI group is responsible for H/sub α/ measurements and the helium removal experiment on the ALT-II experiment in TEXTOR. Initial H/sub α/ measurements and calibration of the detectors were performed on TEXTOR. Several concepts have been investigated and the associated diagnostics identified to implement a helium removal experiment on ALT-II. In collaboration with France, a pump limiter system for steady-state operation is being designed for Tore Supra. In the past year, several concepts for pump limiter systems were studied, and predictive modeling of heat and particle removal was performed. Studies of plasma-surface phenomena were concentrated during the past year on graphites, wall carbonization, erosion/redeposition, and postmortem analysis of limiters. Erosion/redeposition experiments were performed with the 13C technique in collaboration with the JET and TEXTOR groups. Other initiatives include studies of surface effects on the performance of rf components

  19. Experimental investigation of plasma relaxation using a compact coaxial magnetized plasma gun in a background plasma

    Science.gov (United States)

    Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott; University of New Mexico Collaboration; Los Alamos National Laboratory Collaboration

    2013-10-01

    A compact coaxial plasma gun is employed for experimental studies of plasma relaxation in a low density background plasma. Experiments are being conducted in the linear HelCat device at UNM. These studies will advance the knowledge of basic plasma physics in the areas of magnetic relaxation and space and astrophysical plasmas, including the evolution of active galactic jets/radio lobes within the intergalactic medium. The gun is powered by a 120pF ignitron-switched capacitor bank which is operated in a range of 5-10 kV and ~100 kA. Multiple diagnostics are employed to investigate plasma relaxation process. Magnetized Argon plasma bubbles with velocities ~1.2Cs and densities ~1020 m-3 have been achieved. Different distinct regimes of operation with qualitatively different dynamics are identified by fast CCD camera images, with the parameter determining the operation regime. Additionally, a B-dot probe array is employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify detached plasma bubble configurations. Experimental data and analysis will be presented.

  20. Plasma reactor waste management systems

    Science.gov (United States)

    Ness, Robert O., Jr.; Rindt, John R.; Ness, Sumitra R.

    1992-01-01

    The University of North Dakota is developing a plasma reactor system for use in closed-loop processing that includes biological, materials, manufacturing, and waste processing. Direct-current, high-frequency, or microwave discharges will be used to produce plasmas for the treatment of materials. The plasma reactors offer several advantages over other systems, including low operating temperatures, low operating pressures, mechanical simplicity, and relatively safe operation. Human fecal material, sunflowers, oats, soybeans, and plastic were oxidized in a batch plasma reactor. Over 98 percent of the organic material was converted to gaseous products. The solids were then analyzed and a large amount of water and acid-soluble materials were detected. These materials could possibly be used as nutrients for biological systems.

  1. Plasma physics for controlled fusion

    CERN Document Server

    Miyamoto, Kenro

    2016-01-01

    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator includi...

  2. A dynamical model of plasma turbulence in the solar wind.

    Science.gov (United States)

    Howes, G G

    2015-05-13

    A dynamical approach, rather than the usual statistical approach, is taken to explore the physical mechanisms underlying the nonlinear transfer of energy, the damping of the turbulent fluctuations, and the development of coherent structures in kinetic plasma turbulence. It is argued that the linear and nonlinear dynamics of Alfvén waves are responsible, at a very fundamental level, for some of the key qualitative features of plasma turbulence that distinguish it from hydrodynamic turbulence, including the anisotropic cascade of energy and the development of current sheets at small scales. The first dynamical model of kinetic turbulence in the weakly collisional solar wind plasma that combines self-consistently the physics of Alfvén waves with the development of small-scale current sheets is presented and its physical implications are discussed. This model leads to a simplified perspective on the nature of turbulence in a weakly collisional plasma: the nonlinear interactions responsible for the turbulent cascade of energy and the formation of current sheets are essentially fluid in nature, while the collisionless damping of the turbulent fluctuations and the energy injection by kinetic instabilities are essentially kinetic in nature.

  3. Electron heating via the self-excited plasma series resonance in geometrically symmetric multi-frequency capacitive plasmas

    CERN Document Server

    Schuengel, E; Donko, Z; Korolov, I; Derzsi, A; Schulze, J

    2016-01-01

    The self-excitation of Plasma Series Resonance (PSR) oscillations plays an important role in the electron heating dynamics in Capacitively Coupled Radio Frequency (CCRF) plasmas. In a combined approach of PIC/MCC simulations and a theoretical model based on an equivalent circuit, we investigate the self-excitation of PSR oscillations and their effect on the electron heating in geometrically symmetric CCRF plasmas driven by multiple consecutive harmonics. The discharge symmetry is controlled via the Electrical Asymmetry Effect, i.e. by varying the total number of harmonics and tuning the phase shifts between them. It is demonstrated that PSR oscillations will be self-excited under both symmetric and asymmetric conditions, if (i) the charge-voltage relation of the plasma sheaths deviates from a simple quadratic behavior and if (ii) the inductance of the plasma bulk exhibits a temporal modulation. These two effects have been neglected up to now, but we show that they must be included in the model in order to pro...

  4. PLASMA GASIFICATION OF WASTE PLASTICS

    OpenAIRE

    Tadeusz Mączka; Ewa Śliwka; Mateusz Wnukowski

    2013-01-01

    The article presents the process of obtaining liquid fuels and fuel gas in the process of plasma processing of organic materials, including waste plastics. The concept of plasma pyrolysis of plastics was presented and on its basis a prototype installation was developed. The article describes a general rule of operating the installation and its elements in the process and basic operation parameters determined during its start-up. Initial results of processing plastics and the directions furthe...

  5. Intermittency, nonlinear dynamics and dissipation in the solar wind and astrophysical plasmas.

    Science.gov (United States)

    Matthaeus, W H; Wan, Minping; Servidio, S; Greco, A; Osman, K T; Oughton, S; Dmitruk, P

    2015-05-13

    An overview is given of important properties of spatial and temporal intermittency, including evidence of its appearance in fluids, magnetofluids and plasmas, and its implications for understanding of heliospheric plasmas. Spatial intermittency is generally associated with formation of sharp gradients and coherent structures. The basic physics of structure generation is ideal, but when dissipation is present it is usually concentrated in regions of strong gradients. This essential feature of spatial intermittency in fluids has been shown recently to carry over to the realm of kinetic plasma, where the dissipation function is not known from first principles. Spatial structures produced in intermittent plasma influence dissipation, heating, and transport and acceleration of charged particles. Temporal intermittency can give rise to very long time correlations or a delayed approach to steady-state conditions, and has been associated with inverse cascade or quasi-inverse cascade systems, with possible implications for heliospheric prediction.

  6. ITER Plasma Control System Development

    Science.gov (United States)

    Snipes, Joseph; ITER PCS Design Team

    2015-11-01

    The development of the ITER Plasma Control System (PCS) continues with the preliminary design phase for 1st plasma and early plasma operation in H/He up to Ip = 15 MA in L-mode. The design is being developed through a contract between the ITER Organization and a consortium of plasma control experts from EU and US fusion laboratories, which is expected to be completed in time for a design review at the end of 2016. This design phase concentrates on breakdown including early ECH power and magnetic control of the poloidal field null, plasma current, shape, and position. Basic kinetic control of the heating (ECH, ICH, NBI) and fueling systems is also included. Disruption prediction, mitigation, and maintaining stable operation are also included because of the high magnetic and kinetic stored energy present already for early plasma operation. Support functions for error field topology and equilibrium reconstruction are also required. All of the control functions also must be integrated into an architecture that will be capable of the required complexity of all ITER scenarios. A database is also being developed to collect and manage PCS functional requirements from operational scenarios that were defined in the Conceptual Design with links to proposed event handling strategies and control algorithms for initial basic control functions. A brief status of the PCS development will be presented together with a proposed schedule for design phases up to DT operation.

  7. Antimicrobial outcomes in plasma medicine

    Science.gov (United States)

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

    2015-03-01

    Plasma is referred to as the fourth state of matter and is frequently generated in the environment of a strong electric field. The result consists of highly reactive species--ions, electrons, reactive atoms and molecules, and UV radiation. Plasma Medicine unites a number of fields, including Physics, Plasma Chemistry, Cell Biology, Biochemistry, and Medicine. The treatment modality utilizes Cold Atmospheric Plasma (CAP), which is able to sterilize and treat microbes in a nonthermal manner. These gas-based plasma systems operate at close to room temperature and atmospheric pressure, making them very practical for a range of potential treatments and are highly portable for clinical use throughout the health care system. The hypothesis is that gas based plasma kills bacteria, fungus, and viruses but spares mammalian cells. This paper will review systematic work which shows examples of systems and performance in regards to antimicrobial effects and the sparing of mammalian cells. The mechanism of action will be discussed, as well as dosing for the treatment of microbial targets, including sterilization processes, another important healthcare need. In addition, commercial systems will be overviewed and compared, along with evidence-based, patient results. The range of treatments cover wound treatment and biofilms, as well as antimicrobial treatment, with little chance for resistance and tolerance, as in drug regimens. Current clinical studies include applications in dentistry, food treatment, cancer treatment, wound treatment for bacteria and biofilms, and systems to combat health care related infections.

  8. plasmatis Center for Innovation Competence: Controlling reactive component output of atmospheric pressure plasmas in plasma medicine

    Science.gov (United States)

    Reuter, Stephan

    2012-10-01

    The novel approach of using plasmas in order to alter the local chemistry of cells and cell environment presents a significant development in biomedical applications. The plasmatis center for innovation competence at the INP Greifswald e.V. performs fundamental research in plasma medicine in two interdisciplinary research groups. The aim of our plasma physics research group ``Extracellular Effects'' is (a) quantitative space and time resolved diagnostics and modelling of plasmas and liquids to determine distribution and composition of reactive species (b) to control the plasma and apply differing plasma source concepts in order to produce a tailored output of reactive components and design the chemical composition of the liquids/cellular environment and (c) to identify and understand the interaction mechanisms of plasmas with liquids and biological systems. Methods to characterize the plasma generated reactive species from plasma-, gas- and liquid phase and their biological effects will be presented. The diagnostic spectrum ranges from absorption/emission/laser spectroscopy and molecular beam mass spectrometry to electron paramagnetic resonance spectroscopy and cell biological diagnostic techniques. Concluding, a presentation will be given of the comprehensive approach to plasma medicine in Greifswald where the applied and clinical research of the Campus PlasmaMed association is combined with the fundamental research at plasmatis center.

  9. The cathode plasma simulation

    Science.gov (United States)

    Suksila, Thada

    Since its invention at the University of Stuttgart, Germany in the mid-1960, scientists have been trying to understand and explain the mechanism of the plasma interaction inside the magnetoplasmadynamics (MPD) thruster. Because this thruster creates a larger level of efficiency than combustion thrusters, this MPD thruster is the primary cadidate thruster for a long duration (planetary) spacecraft. However, the complexity of this thruster make it difficult to fully understand the plasma interaction in an MPD thruster while operating the device. That is, there is a great deal of physics involved: the fluid dynamics, the electromagnetics, the plasma dynamics, and the thermodynamics. All of these physics must be included when an MPD thruster operates. In recent years, a computer simulation helped scientists to simulate the experiments by programing the physics theories and comparing the simulation results with the experimental data. Many MPD thruster simulations have been conducted: E. Niewood et al.[5], C. K. J. Hulston et al.[6], K. D. Goodfellow[3], J Rossignol et al.[7]. All of these MPD computer simulations helped the scientists to see how quickly the system responds to the new design parameters. For this work, a 1D MPD thruster simulation was developed to find the voltage drop between the cathode and the plasma regions. Also, the properties such as thermal conductivity, electrical conductivity and heat capacity are temperature and pressure dependent. These two conductivity and heat capacity are usually definded as constant values in many other models. However, this 1D and 2D cylindrical symmetry MPD thruster simulations include both temperature and pressure effects to the electrical, thermal conductivities and heat capacity values interpolated from W. F. Ahtye [4]. Eventhough, the pressure effect is also significant; however, in this study the pressure at 66 Pa was set as a baseline. The 1D MPD thruster simulation includes the sheath region, which is the

  10. Plasmas applied atomic collision physics, v.2

    CERN Document Server

    Barnett, C F

    1984-01-01

    Applied Atomic Collision Physics, Volume 2: Plasmas covers topics on magnetically confined plasmas. The book starts by providing the history of fusion research and describing the various approaches in both magnetically and inertially confined plasmas. The text then gives a general discussion of the basic concepts and properties in confinement and heating of a plasma. The theory of atomic collisions that result in excited quantum states, particularly highly ionized impurity atoms; and diverse diagnostic topics such as emission spectra, laser scattering, electron cyclotron emission, particle bea

  11. Microwave reflectometry for fusion plasma diagnostics

    International Nuclear Information System (INIS)

    This document contains a collection of 26 papers on ''Microwave Reflectometry for Fusion Plasma Diagnostics'', presented at the IAEA Technical Committee Meeting of the same name held at the JET Joint Undertaking, Abingdon, United Kingdom, March 4-6, 1992. It contains five papers on the measurement of plasma density profiles, six papers on theory and simulations in support of the development and application of this type of plasma diagnostics, eight papers on the measurement of density transients and fluctuations, and seven on new approaches to reflectometry-based plasma diagnostics. Refs, figs and tabs

  12. Rayleigh-Taylor instability in prominences from numerical simulations including partial ionization effects

    CERN Document Server

    Khomenko, E; de Vicente, A; Collados, M; Luna, M

    2014-01-01

    We study the Rayleigh-Taylor instability (RTI) at a prominence-corona transition region in a non-linear regime. Our aim is to understand how the presence of neutral atoms in the prominence plasma influences the instability growth rate, and the evolution of velocity, magnetic field vector and thermodynamic parameters of turbulent drops. We perform 2.5D numerical simulations of the instability initiated by a multi-mode perturbation at the corona-prominence interface using a single-fluid MHD approach including a generalized Ohm's law. The initial equilibrium configuration is purely hydrostatic and contains a homogeneous horizontal magnetic field forming an angle with the direction in which the plasma is perturbed. We analyze simulations with two different orientations of the magnetic field. For each field orientation we compare two simulations, one for the pure MHD case, and one including the ambipolar diffusion in the Ohm's law (AD case). Other than that, both simulations for each field orientation are identica...

  13. Renormalization and plasma physics

    International Nuclear Information System (INIS)

    A review is given of modern theories of statistical dynamics as applied to problems in plasma physics. The derivation of consistent renormalized kinetic equations is discussed, first heuristically, later in terms of powerful functional techniques. The equations are illustrated with models of various degrees of idealization, including the exactly soluble stochastic oscillator, a prototype for several important applications. The direct-interaction approximation is described in detail. Applications discussed include test particle diffusion and the justification of quasilinear theory, convective cells, E vector x B vector turbulence, the renormalized dielectric function, phase space granulation, and stochastic magnetic fields

  14. The Absence of Plasma in"Spark Plasma Sintering"

    Energy Technology Data Exchange (ETDEWEB)

    Hulbert, Dustin M.; Anders, Andre; Dudina, Dina V.; Andersson, Joakim; Jiang, Dongtao; Unuvar, Cosan; Anselmi-Tamburini, Umberto; Lavernia, Enrique J.; Mukherjee, Amiya K.

    2008-04-10

    Spark plasma sintering (SPS) is a remarkable method for synthesizing and consolidating a large variety of both novel and traditional materials. The process typically uses moderate uni-axial pressures (<100 MPa) in conjunction with a pulsing on-off DC current during operation. There are a number of mechanisms proposed to account for the enhanced sintering abilities of the SPS process. Of these mechanisms, the one most commonly put forth and the one that draws the most controversy involves the presence of momentary plasma generated between particles. This study employees three separate experimental methods in an attempt to determine the presence or absence of plasma during SPS. The methods employed include: in-situ atomic emission spectroscopy, direct visual observation and ultra-fast in-situ voltage measurements. It was found using these experimental techniques that no plasma is present during the SPS process. This result was confirmed using several different powders across a wide spectrum of SPS conditions.

  15. Vortex stabilized electron beam compressed fusion grade plasma

    International Nuclear Information System (INIS)

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  16. Vortex stabilized electron beam compressed fusion grade plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, Ady [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-03-19

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  17. Plasma physics via particle simulation

    International Nuclear Information System (INIS)

    Plasmas are studied by following the motion of many particles in applied and self fields, analytically, experimentally and computationally. Plasmas for magnetic fusion energy devices are very hot, nearly collisionless and magnetized, with scale lengths of many ion gyroradii and Debye lengths. The analytic studies of such plasmas are very difficult as the plasma is nonuniform, anisotropic and nonlinear. The experimental studies have become very expensive in time and money, as the size, density and temperature approach fusion reactor values. Computational studies using many particles and/or fluids have complemented both theories and experiments for many years and have progressed to fully three dimensional electromagnetic models, albeit with hours of running times on the fastest largest computers. Particle simulation methods are presented in some detail, showing particle advance from acceleration to velocity to position, followed by calculation of the fields from charge and current densities and then further particle advance, and so on. Limitations due to the time stepping and use of a spatial grid are given, to avoid inaccuracies and instabilities. Examples are given for an electrostatic program in one dimension of an orbit averaging program, and for a three dimensional electromagnetic program. Applications of particle simulations of plasmas in magnetic and inertial fusion devices continue to grow, as well as to plasmas and beams in peripheral devices, such as sources, accelerators, and converters. (orig.)

  18. Magnetic Field Analysis of Plasma Guide in Galathea Trimyx

    Directory of Open Access Journals (Sweden)

    Jin Xianji

    2016-01-01

    Full Text Available You Galathea Trimyx is a kind of small size, multipole magnetic confinement devices in controlled thermonuclear fusion. Plasma guide is one of important part in Galathea Trimyx which is responsible for transporting fast and slow plasma bunches ejected from plasma gun. The distribution and uniformity of magnetic field in completed plasma guide is analyzed in detail, including in x -axis direction and in z-axis direction. On the basis, the motion of plasma in the guide is discussed.

  19. Magnetic Field Analysis of Plasma Guide in Galathea Trimyx

    OpenAIRE

    Jin Xianji; Tong Weiming; Zhou Tianyi

    2016-01-01

    You Galathea Trimyx is a kind of small size, multipole magnetic confinement devices in controlled thermonuclear fusion. Plasma guide is one of important part in Galathea Trimyx which is responsible for transporting fast and slow plasma bunches ejected from plasma gun. The distribution and uniformity of magnetic field in completed plasma guide is analyzed in detail, including in x -axis direction and in z-axis direction. On the basis, the motion of plasma in the guide is discussed.

  20. Untargeted plasma and tissue metabolomics in rats with chronic kidney disease given AST-120.

    Science.gov (United States)

    Velenosi, Thomas J; Hennop, Anzel; Feere, David A; Tieu, Alvin; Kucey, Andrew S; Kyriacou, Polydoros; McCuaig, Laura E; Nevison, Stephanie E; Kerr, Michael A; Urquhart, Bradley L

    2016-01-01

    Chronic kidney disease (CKD) results in the accumulation of metabolic waste products that are normally cleared by the kidney, known as uremia. Many of these waste products are from bacteria metabolites in the gut. Accumulation of uremic toxins in plasma and tissue, as well as the gut-plasma-tissue metabolic axis are important for understanding pathophysiological mechanisms of comorbidities in CKD. In this study, an untargeted metabolomics approach was used to determine uremic toxin accumulation in plasma, liver, heart and kidney tissue in rats with adenine-induced CKD. Rats with CKD were also given AST-120, a spherical carbon adsorbent, to assess metabolic changes in plasma and tissues with the removal of gut-derived uremic toxins. AST-120 decreased >55% of metabolites that were increased in plasma, liver and heart tissue of rats with CKD. CKD was primarily defined by 8 gut-derived uremic toxins, which were significantly increased in plasma and all tissues. These metabolites were derived from aromatic amino acids and soy protein including: indoxyl sulfate, p-cresyl sulfate, hippuric acid, phenyl sulfate, pyrocatechol sulfate, 4-ethylphenyl sulfate, p-cresol glucuronide and equol 7-glucuronide. Our results highlight the importance of diet and gut-derived metabolites in the accumulation of uremic toxins and define the gut-plasma-tissue metabolic axis in CKD. PMID:26932318

  1. Plasma effects in high frequency radiative transfer

    International Nuclear Information System (INIS)

    This paper is intended as a survey of collective plasma processes which can affect the transfer of high frequency radiation in a hot dense plasma. We are rapidly approaching an era when this subject will become important in the laboratory. For pedagogical reasons we have chosen to examine plasma processes by relating them to a particular reference plasma which will consist of fully ionized carbon at a temperature kT=1 KeV (1070K) and an electron density N = 3 x 1023cm-3, (which corresponds to a mass density rho = 1 gm/cm3 and an ion density N/sub i/ = 5 x 1022 cm-3). We will consider the transport in such a plasma of photons ranging from 1 eV to 1 KeV in energy. Such photons will probably be frequently used as diagnostic probes of hot dense laboratory plasmas

  2. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  3. Plasma Free Metanephrines

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? Also known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine ...

  4. PlasmaLab/EkoPlasma - The Future of Complex Plasma Research in Space

    Science.gov (United States)

    Knapek, Christina; Fortov, Vladimir; Huber, Peter; Mohr, Daniel; Konopka, Uwe; Lipaev, Andrey; Molotkov, Vladimir; Petrov, Oleg; Zähringer, Erich; Thomas, Hubertus

    2016-07-01

    The PlasmaLab project, a Russian-German cooperation, has the aim to develop a future laboratory for the investigation of complex plasmas under microgravity conditions on the International Space Station (ISS). Within the project, a new plasma chamber, the Zyflex chamber, has been developed and is now being prepared to be launched to the ISS in 2020 as a laboratory setup with the name EkoPlasma (Experiment komplex Plasma). The Zyflex chamber is a large, cylindrical plasma chamber with parallel, rf-driven electrodes and a flexible inner geometry. It is designed to extend the accessible experimental parameter range and to allow an independent control of the plasma parameters, therefore increasing the experimental possibilities and expected knowledge gain significantly. Further, a 3D optical diagnostic will allow for the study of particle dynamics in 3D realtime. Possible future research topics include e.g. phase transitions, the dynamics of liquids, phase separation, or turbulence. The experimental setup will be presented, as well as some preliminary results of experiments on earth and in parabolic flights to visualize the possibilities of this new laboratory. This work and some of the authors are funded by DLR/BMWi (FKZ 50WM1441).

  5. The Wisconsin Plasma Astrophysics Laboratory

    CERN Document Server

    Forest, C B; Brookhart, M; Cooper, C M; Clark, M; Desangles, V; Egedal, J; Endrizzi, D; Miesch, M; Khalzov, I V; Li, H; Milhone, J; Nornberg, M; Olson, J; Peterson, E; Roesler, F; Schekochihin, A; Schmitz, O; Siller, R; Spitkovsky, A; Stemo, A; Wallace, J; Weisberg, D; Zweibel, E

    2015-01-01

    The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries which mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a 10 m$^3$, fully ionized, magnetic-field free plasma in a spherical geometry. Plasma parameters of $ T_{e}\\approx5-20$ eV and $n_{e}\\approx10^{11}-5\\times10^{12}$ cm$^{-3}$ provide an ideal testbed for a range of astrophysical experiments including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds, and more. This article describes the capabilities of WiPAL along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.

  6. New wave effects in nonstationary plasma

    Science.gov (United States)

    Schmit, Paul

    2012-10-01

    In plasma undergoing compression, embedded waves can have very unusual and possibly useful properties. For example, part of the mechanical energy of compressing plasma can be transferred controllably to hot electrons by seeding the plasma with plasma waves. Under compression, wherein wave action is conserved, the wave energy grows as its frequency and wavenumber change adiabatically, until, suddenly, the wave damps, resulting in switch-like production not only of heat [1], but also voltage and current [2]. These bursts can be controlled precisely in time by prescribing the compression script. Several classic problems in wave physics, including the bump-on-tail instability, exhibit new effects under compression [3]. In addition, the waves undergoing compression or expansion affect fundamental properties of plasma, such as the plasma compressibility; moreover, and rather remarkably, nonlinear waves, such as BGK modes, affect the plasma compressibility differently [4]. Wave-particle interactions mediated by plasma compression also can enhance the performance of plasma-based particle accelerators. To describe numerically all these effects, novel particle-in-cell simulations were developed. These findings point towards potentially beneficial applications, including in inertial confinement fusion and high energy density plasma physics, where extreme compression is exercised on dense plasma, which could be seeded with waves. [4pt] [1] P. F. Schmit, I. Y. Dodin, and N. J. Fisch, PRL 105, 175003 (2010).[0pt] [2] P. F. Schmit and N. J. Fisch, PRL 108, 215003 (2012).[0pt] [3] P. F. Schmit et al., J. Plasma Phys. 77, 629 (2011).[0pt] [4] P. F. Schmit, I. Y. Dodin, and N. J. Fisch, Phys. Plasmas 18, 042103 (2011).[0pt] [5] P. F. Schmit and N. J. Fisch, Phys. Plasmas 18, 102102 (2011).

  7. Plasma diagnostics by means of electric probes; Diagnostico del plasma por medio de sondas electricas

    Energy Technology Data Exchange (ETDEWEB)

    Colunga S, S

    1991-04-15

    In this work a summary of the classical theoretical models to interpret the characteristic curve of a Langmuir electric probe placed in a plasma without magnetic field and with the one is made. The methodology for the electron temperature calculation and the density of the plasma in both cases is given, starting from the characteristic curve of the probe, as well as the approaches for the correct application of this diagnostic method of the plasma. (Author)

  8. Pulsed RF Plasma Source for Materials Processing

    Science.gov (United States)

    Nasiruddin, Abutaher Mohammad

    A pulsed rf plasma source was evaluated for materials processing. A pulsed rf discharge of carbon tetrafluoride (CF_4), sulfur hexafluoride (SF _6), oxygen (O_2), or acetylene (C_2H_2 ) created the plasmas. The frequency and duration of the rf discharge were about 290 kHz and 30 musec, respectively. The repetition rate was 1 discharge per minute. Plasma diagnostics included Langmuir probes, a photodiode dectector, an optical multichannel analyzer (OMA), and a microwave interferometer. Langmuir probe measurements showed that at a position 67 cm away from the rf coil, CF_4 plasma arrived in separate packets. Plasma densities and electron temperatures at this position were in the range 4 times 10^{11} cm ^{-3} to 1.8 times 10^{13} cm ^{-3} and 2 eV to 8.3 eV, respectively. The OMA measurements identified neutral atomic fluorine in the CF_4 plasma and neutral atomic oxygen in the O_2 plasma. A plasma slab model of the microwave interferometer was applied to predict the interferometer response. The measured response was found to be almost identical to the predicted response. The influence of different reactor parameters on plasma parameters was studied. Metal barriers of different geometry were used to control the ratio of charged particles to atomic neutrals in the plasma chamber. Four plasma structures were identified: precursor plasma, shock induced plasma, driver plasma, and delayed glow plasma. Pulsed CF _4 and SF_6 plasmas were used to etch silicon dioxide (SiO_2 ) grown on silicon wafers. The SF_6 plasma etched SiO_2 at a rate of about 0.71 A per discharge and the CF_4 plasma deposited a non-uniform film (possibly polymer) instead of etching. The C_2H _2 plasma deposited plasma polymerized acetylene on a KBr pellet with a deposition rate of 127 A per discharge. An FT-IR spectrum of the deposited film showed that carbon -to-carbon double bonds as well as carbon-to-hydrogen bonds were present. This device can be used in plasma assisted deposition and/or synthesis

  9. Comprehensive and quantitative proteomic analyses of zebrafish plasma reveals conserved protein profiles between genders and between zebrafish and human.

    Science.gov (United States)

    Li, Caixia; Tan, Xing Fei; Lim, Teck Kwang; Lin, Qingsong; Gong, Zhiyuan

    2016-01-01

    Omic approaches have been increasingly used in the zebrafish model for holistic understanding of molecular events and mechanisms of tissue functions. However, plasma is rarely used for omic profiling because of the technical challenges in collecting sufficient blood. In this study, we employed two mass spectrometric (MS) approaches for a comprehensive characterization of zebrafish plasma proteome, i.e. conventional shotgun liquid chromatography-tandem mass spectrometry (LC-MS/MS) for an overview study and quantitative SWATH (Sequential Window Acquisition of all THeoretical fragment-ion spectra) for comparison between genders. 959 proteins were identified in the shotgun profiling with estimated concentrations spanning almost five orders of magnitudes. Other than the presence of a few highly abundant female egg yolk precursor proteins (vitellogenins), the proteomic profiles of male and female plasmas were very similar in both number and abundance and there were basically no other highly gender-biased proteins. The types of plasma proteins based on IPA (Ingenuity Pathway Analysis) classification and tissue sources of production were also very similar. Furthermore, the zebrafish plasma proteome shares significant similarities with human plasma proteome, in particular in top abundant proteins including apolipoproteins and complements. Thus, the current study provided a valuable dataset for future evaluation of plasma proteins in zebrafish. PMID:27071722

  10. Microscopic dynamics of plasmas and chaos

    International Nuclear Information System (INIS)

    Some of the key intellectual foundations of plasma physics are in danger of becoming a lost art. Fortunately, however, this threat recedes with the publication of this valuable book. It renders accessible those aspects of theoretical plasma physics that are best approached from the perspectives of classical mechanics, in both its early nineteenth century and late twentieth century manifestations. Half a century has elapsed since the publication of seminal papers such as those by Bohm and Pines (1951), van Kampen (1955), and Bernstein, Greene and Kruskal (1957). These papers served to address a fundamental question of physics - namely the relation between degrees of freedom that exist at the individual particle level of description, and those that exist at the collective level - in the plasma context. The authors of the present book have played a major role in the investigation of this question from an N-body standpoint, which can be divided into two linked themes. First, those topics that can be illuminated by analytical methods that lie in the tradition of classical mechanics that stretches back to Lagrange, Legendre and Hamilton. Second, those topics that benefit from the insights developed following the redevelopment of classical mechanics in relation to chaos theory in the 1980s and subsequently. The working plasma physicist who wishes to dig more deeply in this field is faced at present with a number of challenges. These may include a perception that this subfield is of limited relevance to mission-oriented questions of plasma performance; a perception of the research literature as being self-contained and inaccessible; and, linked to this, unfamiliarity with the mathematical tools. The latter problem is particularly pressing, given the limited coverage of classical mechanics in many undergraduate physics courses. The book by Elskens and Escande meets many of the challenges outlined above. The rewards begin early, by the end of the second chapter, with

  11. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    Energy Technology Data Exchange (ETDEWEB)

    Witherspoon, F. Douglas [HyperV Technologies Corp.; Welch, Dale R. [Voss Scientific, LLC; Thompson, John R. [FAR-TECH, Inc.; MacFarlane, Joeseph J. [Prism Computational Sciences Inc.; Phillips, Michael W. [Advanced Energy Systems, Inc.; Bruner, Nicki [Voss Scientific, LLC; Mostrom, Chris [Voss Scientific, LLC; Thoma, Carsten [Voss Scientific, LLC; Clark, R. E. [Voss Scientific, LLC; Bogatu, Nick [FAR-TECH, Inc.; Kim, Jin-Soo [FAR-TECH, Inc.; Galkin, Sergei [FAR-TECH, Inc.; Golovkin, Igor E. [Prism Computational Sciences, Inc.; Woodruff, P. R. [Prism Computational Sciences, Inc.; Wu, Linchun [HyperV Technologies Corp.; Messer, Sarah J. [HyperV Technologies Corp.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism

  12. Boundary Plasma Turbulence Simulations for Tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Xu, X; Umansky, M; Dudson, B; Snyder, P

    2008-05-15

    The boundary plasma turbulence code BOUT models tokamak boundary-plasma turbulence in a realistic divertor geometry using modified Braginskii equations for plasma vorticity, density (ni), electron and ion temperature (T{sub e}; T{sub i}) and parallel momenta. The BOUT code solves for the plasma fluid equations in a three dimensional (3D) toroidal segment (or a toroidal wedge), including the region somewhat inside the separatrix and extending into the scrape-off layer; the private flux region is also included. In this paper, a description is given of the sophisticated physical models, innovative numerical algorithms, and modern software design used to simulate edge-plasmas in magnetic fusion energy devices. The BOUT code's unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

  13. Plasma-wall interaction; Interaction plasma paroi

    Energy Technology Data Exchange (ETDEWEB)

    Reichle, R

    2004-07-01

    This document gathers the 43 slides presented in the framework of the week long lecture 'hot plasmas 2004' and dedicated to plasma-wall interaction in a tokamak. This document is divided into 4 parts: 1) thermal load on the wall, power extraction and particle recovery, 2) basic edge plasma physics, 3) processes that drive the plasma-solid interaction, and 4) material conditioning (surface treatment...) for ITER.

  14. Lectures in plasma diagnostics

    International Nuclear Information System (INIS)

    This paper discusses the following topics on plasma diagnostics: Electric probes in flowing and magnetized plasmas; Electron cyclotron emission absorption; Magnetic diagnostics; Spectroscopy; and Thomson Scattering

  15. Low voltage operation of plasma focus

    International Nuclear Information System (INIS)

    Plasma foci of compact sizes and operating with low energies (from tens of joules to few hundred joules) have found application in recent years and have attracted plasma-physics scientists and engineers for research in this direction. We are presenting a low energy and miniature plasma focus which operates from a capacitor bank of 8.4 μF capacity, charged at 4.2-4.3 kV and delivering approximately 52 kA peak current at approximately 60 nH calculated circuit inductance. The total circuit inductance includes the plasma focus inductance. The reported plasma focus operates at the lowest voltage among all reported plasma foci so far. Moreover the cost of capacitor bank used for plasma focus is nearly 20 U.S. dollars making it very cheap. At low voltage operation of plasma focus, the initial breakdown mechanism becomes important for operation of plasma focus. The quartz glass tube is used as insulator and breakdown initiation is done on its surface. The total energy of the plasma focus is approximately 75 J. The plasma focus system is made compact and the switching of capacitor bank energy is done by manual operating switch. The focus is operated with hydrogen and deuterium filled at 1-2 mbar.

  16. Modelling of Complex Plasmas

    Science.gov (United States)

    Akdim, Mohamed Reda

    2003-09-01

    not included. Results are presented for situations in which the dust signi_cantly changes the discharge characteristics, both by a strong reduction of the electron density and by altering the electric field by its charge. Simulations for dust with a radius of 2 mu-m show that the stationary solution of the dust density and the average electric field depend on the total amount of the dust. The presence of dust enhances the deposition rate of amorphous silicon 2 at the electrodes because of the rise in the average electron energy associated with the decrease of the electron density and the constraint of a constant power input. This increase of deposition rate has also been observed in experiments by others. To study the behavior of dust in a less complicated environment, experiments in non-reactive plasmas have been carried out by a number of research groups. In these experiments the dust particles are injected through the electrodes in an argon discharge. These experiments have shown very interesting phenomena. Dust particles start to interact with each other in the discharge and form two-dimensional Coulomb clusters. These experiments often show an appearance of a void, a dustfree region in the discharge. Similar experiments have also been carried out under microgravity. These experiments have shown three-dimensional Coulomb clusters of dust particles also with the appearance of a void. Also rotating dust clouds (vortices) near the edges of the electrodes have been observed, that tend to rotate as long as the plasmas is on. To understand the behavior of the particles, we have developed a two-dimensional fluid model for a dusty argon plasma in which the plasma and dust parameters are solved self-consistently to study the behavior of dust particles. Simulations for dust with a radius of 7.5 mu-m show that a double space charge layer is created around the sharp boundary of the dust crystal. The inter-particle interaction is taken into account by means of an equation of

  17. Cluster plasma and its dispersion relation

    International Nuclear Information System (INIS)

    It is shown that unlike a gas plasma or an electron plasma in a metal, an ionized cluster material (open-quotes cluster plasmaclose quotes) permits propagation below the plasma cut-off of electromagnetic (EM) waves whose phase velocity is close to but below the speed of light. Its unique properties allow a variety of applications, including direct acceleration of particles with its EM fields and the phase matching of waves of high harmonic generation (HHG)

  18. Telomerase activity in plasma cell dyscrasias

    OpenAIRE

    Xu, D; Zheng, C.; Bergenbrant, S; Holm, G; Björkholm, M.; Yi, Q; Gruber, A

    2001-01-01

    Activation of telomerase is essential for in vitro cellular immortalization and tumorigenesis. In the present study, we investigated telomerase activation and its implications in plasma cell dyscrasias including monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM) and plasma cell leukaemia (PCL). All 5 patients with MGUS exhibited normal levels of telomerase activity in their plasma cells. Elevated telomerase activity was found in the samples from 21/27 patients wi...

  19. Optics and Plasma Research Department annual progress report for 2004

    DEFF Research Database (Denmark)

    Bindslev, Henrik; Lynov, Jens-Peter; Pedersen, C.;

    2005-01-01

    , optical materials, biophotonics, fusion plasma physics, and industrial plasma technology. The department employs key technologies in micro- and nanotechnology for optical systems, temperaturecalibration, and infrared measurement techniques. The research is supported by several EU programmes, including...

  20. Models of bovine babesiosis including juvenile cattle.

    Science.gov (United States)

    Saad-Roy, C M; Shuai, Zhisheng; van den Driessche, P

    2015-03-01

    Bovine Babesiosis in cattle is caused by the transmission of protozoa of Babesia spp. by ticks as vectors. Juvenile cattle (resistance to Bovine Babesiosis, rarely show symptoms, and acquire immunity upon recovery. Susceptibility to the disease varies between breeds of cattle. Models of the dynamics of Bovine Babesiosis transmitted by the cattle tick that include these factors are formulated as systems of ordinary differential equations. Basic reproduction numbers are calculated, and it is proved that if these numbers are below the threshold value of one, then Bovine Babesiosis dies out. However, above the threshold number of one, the disease may approach an endemic state. In this case, control measures are suggested by determining target reproduction numbers. The percentage of a particular population (for example, the adult bovine population) needed to be controlled to eradicate the disease is evaluated numerically using Columbia data from the literature. PMID:25715822

  1. The ionospheric source of magnetospheric plasma is not a black box input for global models

    Science.gov (United States)

    Welling, D. T.; Liemohn, M. W.

    2016-06-01

    Including ionospheric outflow in global magnetohydrodynamic models of near-Earth outer space has become an important step toward understanding the role of this plasma source in the magnetosphere. Of the existing approaches, however, few tie the outflowing particle fluxes to magnetospheric conditions in a self-consistent manner. Doing so opens the magnetosphere-ionosphere system to nonlinear mass-energy feedback loops, profoundly changing the behavior of the magnetosphere-ionosphere system. Based on these new results, it is time for the community eschew treating ionospheric outflow as a simple black box source of magnetospheric plasma.

  2. Fusion plasma physics

    CERN Document Server

    Stacey, Weston M

    2012-01-01

    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  3. How to model quantum plasmas

    CERN Document Server

    Manfredi, G

    2005-01-01

    Traditional plasma physics has mainly focused on regimes characterized by high temperatures and low densities, for which quantum-mechanical effects have virtually no impact. However, recent technological advances (particularly on miniaturized semiconductor devices and nanoscale objects) have made it possible to envisage practical applications of plasma physics where the quantum nature of the particles plays a crucial role. Here, I shall review different approaches to the modeling of quantum effects in electrostatic collisionless plasmas. The full kinetic model is provided by the Wigner equation, which is the quantum analog of the Vlasov equation. The Wigner formalism is particularly attractive, as it recasts quantum mechanics in the familiar classical phase space, although this comes at the cost of dealing with negative distribution functions. Equivalently, the Wigner model can be expressed in terms of $N$ one-particle Schr{\\"o}dinger equations, coupled by Poisson's equation: this is the Hartree formalism, wh...

  4. Plasma Structure and Dynamics

    Science.gov (United States)

    Karpen, Judith T.

    Despite over a century of observations, the physical processes by which prominence plasma forms and evolves remain controversial. In this chapter we review the observational constraints on all mass formation models, review the four leading models—injection, levitation, evaporation-condensation, and magneto-thermal convection, describe the strengths and weaknesses of each model, and point out opportunities for future work. As needed, short tutorials are provided on fundamental physical mechanisms and concepts not covered in other chapters, including magnetic reconnection and energy balance in coronal loops.

  5. Study of wave-particle interaction from the linear regime to dynamical chaos in a magnetized plasma

    International Nuclear Information System (INIS)

    Deterministic chaos generated by the interaction between charged particles and electrostatic plasma waves has been observed in a linear magnetized plasma. The target plasma is created by a barium Q-source, guaranteeing low fluctuation levels and a high degree of uniformity over an extended plasma volume. Characteristics of the background plasma are investigated by a variety of diagnostic techniques, including laser induced fluorescence (LIF) and optical tagging (OT). Particular tagging schemes and specific theoretical approaches to data interpretation (both for LIF and OT) have been developed during this work. As part of these background plasma studies, special attention has been devoted to an investigation of test-ion cross-field transport under different conditions. Test-ions are created and followed in their motion across the magnetic field lines via spin state tagging. In the unperturbed plasma this motion is found to be a diffusive process, supported by classical mechanisms, even in the presence of relatively high pressures of non-reactive neutral gases injected into the plasma volume. Electrostatic waves are excited using a ring antenna structure encircling the plasma column and electrically isolated from it. This system has been chosen on the basis of a comparative analysis of different ion wave launching methods, including the use of grids, inductive coils coupled electromagnetically to the plasma and modulated high frequency electron waves. Two modes propagating parallel to the magnetic field, one of which has two perpendicular components (ion Bernstein and ion acoustic-like waves), characterize the spectrum excited by the electrostatic ring antenna for a single frequency, f, chosen in the range fcici. (author) figs., tabs., 134 refs

  6. Generalized fluid theory including non-Maxwellian kinetic effects

    CERN Document Server

    Izacard, Olivier

    2016-01-01

    The results obtained by the plasma physics community for the validation and the prediction of turbulence and transport in magnetized plasma come mainly from the use of very CPU-consuming particle-in-cell or (gyro)kinetic codes which naturally include non-Maxwellian kinetic effects. To date, fluid codes are not considered to be relevant for the description of these kinetic effects. Here, after revisiting the limitations of the current fluid theory developed in the 19th century, we generalize the fluid theory including kinetic effects such as non-Maxwellian super-thermal tails with as few fluid equations as possible. The collisionless and collisional fluid closures from the nonlinear Landau Fokker-Planck collision operator are shown for an arbitrary collisionality. Indeed, the first fluid models associated with two examples of collisionless fluid closures are obtained by assuming an analytic non-Maxwellian distribution function (e.g., the INMDF [O. Izacard, Phys. Plasmas 23, 082504 (2016)]). One of the main dif...

  7. Aerosol simulation including chemical and nuclear reactions

    Energy Technology Data Exchange (ETDEWEB)

    Marwil, E.S.; Lemmon, E.C.

    1985-01-01

    The numerical simulation of aerosol transport, including the effects of chemical and nuclear reactions presents a challenging dynamic accounting problem. Particles of different sizes agglomerate and settle out due to various mechanisms, such as diffusion, diffusiophoresis, thermophoresis, gravitational settling, turbulent acceleration, and centrifugal acceleration. Particles also change size, due to the condensation and evaporation of materials on the particle. Heterogeneous chemical reactions occur at the interface between a particle and the suspending medium, or a surface and the gas in the aerosol. Homogeneous chemical reactions occur within the aersol suspending medium, within a particle, and on a surface. These reactions may include a phase change. Nuclear reactions occur in all locations. These spontaneous transmutations from one element form to another occur at greatly varying rates and may result in phase or chemical changes which complicate the accounting process. This paper presents an approach for inclusion of these effects on the transport of aerosols. The accounting system is very complex and results in a large set of stiff ordinary differential equations (ODEs). The techniques for numerical solution of these ODEs require special attention to achieve their solution in an efficient and affordable manner. 4 refs.

  8. A High Temperature Liquid Plasma Model of the Sun

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2007-01-01

    Full Text Available In this work, a liquid model of the Sun is presented wherein the entire solar mass is viewed as a high density/high energy plasma. This model challenges our current understanding of the densities associated with the internal layers of the Sun, advocating a relatively constant density, almost independent of radial position. The incompressible nature of liquids is advanced to prevent solar collapse from gravitational forces. The liquid plasma model of the Sun is a non-equilibrium approach, where nuclear reactions occur throughout the solar mass. The primary means of addressing internal heat transfer are convection and conduction. As a result of the convective processes on the solar surface, the liquid model brings into question the established temperature of the solar photosphere by highlighting a violation of Kirchhoff’s law of thermal emission. Along these lines, the model also emphasizes that radiative emission is a surface phenomenon. Evidence that the Sun is a high density/high energy plasma is based on our knowledge of Planckian thermal emission and condensed matter, including the existence of pressure ionization and liquid metallic hydrogen at high temperatures and pressures. Prior to introducing the liquid plasma model, the historic and scientific justifications for the gaseous model of the Sun are reviewed and the gaseous equations of state are also discussed.

  9. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Our theoretical research on dust-plasma interactions has concentrated on three main areas: (a)studies of grain charging and applications; (b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; (c) waves in strongly coupled dusty plasmas.

  10. Characterization of pulsed atmospheric-pressure plasma streams (PAPS) generated by a plasma gun

    International Nuclear Information System (INIS)

    An experimental study of atmospheric-pressure rare gas plasma propagation in a high-aspect-ratio capillary is reported. The plasma is generated with a plasma gun device based on a dielectric barrier discharge (DBD) reactor powered by either nanosecond or microsecond rise-time high-voltage pulses at single-shot to multi-kHz frequencies. The influence of the voltage waveform, pulse polarity, pulse repetition rate and capillary material have been studied using nanosecond intensified charge-coupled device imaging and plasma-front velocity measurements. The evolution of the plasma appearance during its propagation and the study of the role of the different experimental parameters lead us to suggest a new denomination of pulsed atmospheric-pressure plasma streams to describe all the plasma features, including the previously so-called plasma bullet. The unique properties of such non-thermal plasma launching in capillaries, far from the primary DBD plasma, are associated with a fast ionization wave travelling with velocity in the 107–108 cm s−1 range. Voltage pulse tailoring is shown to allow for a significant improvement of such plasma delivery. Thus, the plasma gun device affords unique opportunities in biomedical endoscopic applications. (paper)

  11. Preliminary scaling laws for plasma current, ion kinetic temperature, and plasma number density in the NASA Lewis bumpy torus plasma

    Science.gov (United States)

    Roth, J. R.

    1976-01-01

    Parametric variation of independent variables which may affect the characteristics of bumpy torus plasma have identified those which have a significant effect on the plasma current, ion kinetic temperature, and plasma number density, and those which do not. Empirical power law correlations of the plasma current, and the ion kinetic temperature and number density were obtained as functions of potential applied to the midplane electrode rings, the background neutral gas pressure, and the magnetic field strength. Additional parameters studied included the type of gas, the polarity of the midplane electrode rings, the mode of plasma operation, and the method of measuring the plasma number density. No significant departures from the scaling laws appear to occur at the highest ion kinetic temperatures or number densities obtained to date.

  12. Theory of nanorod antenna resonances including end-reflection phase

    Science.gov (United States)

    Su, Wei; Li, Xiangyin; Bornemann, Jens; Gordon, Reuven

    2015-04-01

    We present a fully analytic theory for nanorod resonances including the phase of reflection from the rounded ends using a transmission line approach. It combines the circuit theory response of spherical nanoparticles with standard transmission line theory using the Sommerfeld wave dispersion. The approach agrees well with comprehensive numerical calculations.

  13. Manufacturing technology development for vacuum vessel and plasma facing components

    Energy Technology Data Exchange (ETDEWEB)

    Laitinen, Arttu [Metso Powdermet, P.O. Box 237, FIN 33101 Tampere (Finland)]. E-mail: arttu.laitinen@metso.com; Liimatainen, Jari [Metso Powdermet, P.O. Box 237, FIN 33101 Tampere (Finland); Hallila, Pentti [Metso Powdermet, P.O. Box 237, FIN 33101 Tampere (Finland)

    2005-11-15

    Vacuum vessel and plasma facing components of the ITER construction including shield modules and primary first wall panels have great impact on the production costs and reliability of the installation. From the manufacturing technology point of view, accuracy of shape, properties of the various austenitic stainless steel/austenitic stainless steel interfaces or CuCrZr/austenitic stainless steel interfaces as well as those of the base materials are crucial for technical reliability of the construction. The current approach in plasma facing components has been utilisation of solid-HIP technology and solid-powder-HIP technology. Due to the large size of especially shield modules shape, control of the internal cavities and cooling channels is extremely demanding. This requires strict control of the raw materials and manufacturing parameters.

  14. A technique to reduce plasma armature formation voltage

    Science.gov (United States)

    Jamison, Keith A.; Littrell, Donald M.

    1991-01-01

    Experimental results from railgun firings using different shapes of initiation foils are presented. These foils have been designed to vaporize into a plasma armature with reduced transient voltages. A design criteria was developed to ensure that all portions of the foil vaporize at slightly different times. Using this approach, a factor of three reduction in the voltage transient during plasma armature initiation has been observed. The impact of the armature voltage transient is discussed, along with a description of design techniques, test conditions, and experimental findings. To quantify the results, a model of current commutation which includes transient armature voltage data was developed. However, the results of the reduced transient voltage spike do not show shorter commutation time.

  15. Transport and radial electric field in torus plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Masao; Nakajima, Noriyoshi; Sugama, Hideo [National Inst. for Fusion Science, Toki, Gifu (Japan); Maluckov, Aleksandra A. [University of Nis, Prirodno-Matematicki Fakultet, FR (Yugoslavia); Satake, Shinsuke [Graduate University for Advanced Studies, Hayama, Kanagawa (Japan)

    2002-12-01

    Transport phenomena in torus plasmas are discussed focusing on the generation of the neoclassical radial electric field. A sophisticated {delta}f Monte Carlo particle simulation code 'FORTEC' is developed including the effect of finite orbit width (FOW), which is the non-local property of the plasma transport. It will be shown that the neoclassical radial electric field in the axisymmetric tokamak is generated due to this FOW effect. The Lagrangian approach is applied to construct a non-local transport theory in the region of near-axis. The reduction of the heat diffusivity toward the axis will be shown. From a statistical point of view, diffusion processes are studied in the presence of irregular magnetic fields. It is shown that the diffusion processes are non-local in almost all the cases if there are some irregularities in the magnetic field. (author)

  16. Introduction to plasma dynamics

    CERN Document Server

    Morozov, A I

    2013-01-01

    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  17. Magnetic stresses in ideal MHD plasmas

    DEFF Research Database (Denmark)

    Jensen, V.O.

    1995-01-01

    The concept of magnetic stresses in ideal MHD plasma theory is reviewed and revisited with the aim of demonstrating its advantages as a basis for calculating and understanding plasma equilibria. Expressions are derived for the various stresses that transmit forces in a magnetized plasma...... and it is shown that the resulting magnetic forces on a finite volume element can be obtained by integrating the magnetic stresses over the surface of the element. The concept is used to rederive and discuss the equilibrium conditions for axisymmetric toroidal plasmas, including the virial theorem...

  18. Plasma Dispersion Function for the Kappa Distribution

    Science.gov (United States)

    Podesta, John J.

    2004-01-01

    The plasma dispersion function is computed for a homogeneous isotropic plasma in which the particle velocities are distributed according to a Kappa distribution. An ordinary differential equation is derived for the plasma dispersion function and it is shown that the solution can be written in terms of Gauss' hypergeometric function. Using the extensive theory of the hypergeometric function, various mathematical properties of the plasma dispersion function are derived including symmetry relations, series expansions, integral representations, and closed form expressions for integer and half-integer values of K.

  19. Development of a plasma panel muon detector

    Science.gov (United States)

    Levin, D. S.; Ball, R.; Beene, J. R.; Benhammou, Y.; Chapman, J. W.; Dai, T.; Etzion, E.; Friedman, P. S.; Ben Moshe, M.; Silver, Y.; Varner, R. L.; Weaverdyck, C.; White, S.; Zhou, B.

    2011-10-01

    A radiation detector technology based on plasma display panels (PDPs), the underlying engine of panel plasma television displays, is being investigated. Emerging from this well-established television technology is the Plasma Panel Sensor (PPS), a novel variant of the micro-pattern radiation detector. The PPS is fundamentally a fast, high-resolution detector comprised of an array of plasma discharge cells, operating in a hermetically sealed gas mixture. We report on the PPS development effort, including proof-of-principle results of laboratory signal observations.

  20. Experimental studies of collisional plasma shocks and plasma interpenetration via merging supersonic plasma jets

    Science.gov (United States)

    Hsu, S. C.; Moser, A. L.; Merritt, E. C.; Adams, C. S.

    2015-11-01

    Over the past 4 years on the Plasma Liner Experiment (PLX) at LANL, we have studied obliquely and head-on-merging supersonic plasma jets of an argon/impurity or hydrogen/impurity mixture. The jets are formed/launched by pulsed-power-driven railguns. In successive experimental campaigns, we characterized the (a) evolution of plasma parameters of a single plasma jet as it propagated up to ~ 1 m away from the railgun nozzle, (b) density profiles and 2D morphology of the stagnation layer and oblique shocks that formed between obliquely merging jets, and (c) collisionless interpenetration transitioning to collisional stagnation between head-on-merging jets. Key plasma diagnostics included a fast-framing CCD camera, an 8-chord visible interferometer, a survey spectrometer, and a photodiode array. This talk summarizes the primary results mentioned above, and highlights analyses of inferred post-shock temperatures based on observations of density gradients that we attribute to shock-layer thickness. We also briefly describe more recent PLX experiments on Rayleigh-Taylor-instability evolution with magnetic and viscous effects, and potential future collisionless shock experiments enabled by low-impurity, higher-velocity plasma jets formed by contoured-gap coaxial guns. Supported by DOE Fusion Energy Sciences and LANL LDRD.